clang-tidy fixes

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

.github/workflows/reusable-build-test-config.yml

@@ -298,7 +298,7 @@ jobs:
 
       - name: Upload coverage report
         if: ${{ github.repository == 'XRPLF/rippled' && !inputs.build_only && env.COVERAGE_ENABLED == 'true' }}
-        uses: codecov/codecov-action@671740ac38dd9b0130fbe1cec585b89eea48d3de # v5.5.2
+        uses: codecov/codecov-action@1af58845a975a7985b0beb0cbe6fbbb71a41dbad # v5.5.3
         with:
           disable_search: true
           disable_telem: true

CMakeLists.txt

@@ -93,6 +93,7 @@ find_package(OpenSSL REQUIRED)
 find_package(secp256k1 REQUIRED)
 find_package(SOCI REQUIRED)
 find_package(SQLite3 REQUIRED)
+find_package(wasmi REQUIRED)
 find_package(xxHash REQUIRED)
 
 target_link_libraries(

cfg/xrpld-example.cfg

@@ -1272,6 +1272,39 @@
 #       Example:
 #           owner_reserve = 2000000      # 2 XRP
 #
+#   extension_compute_limit = <gas>
+#
+#       The extension compute limit is the maximum amount of gas that can be
+#       consumed by a single transaction. The gas limit is used to prevent
+#       transactions from consuming too many resources.
+#
+#       If this parameter is unspecified, xrpld will use an internal
+#       default. Don't change this without understanding the consequences.
+#
+#       Example:
+#           extension_compute_limit = 1000000      # 1 million gas
+#
+#   extension_size_limit = <bytes>
+#
+#       The extension size limit is the maximum size of a WASM extension in
+#       bytes. The size limit is used to prevent extensions from consuming
+#       too many resources.
+#
+#       If this parameter is unspecified, xrpld will use an internal
+#       default. Don't change this without understanding the consequences.
+#
+#       Example:
+#           extension_size_limit = 100000      # 100 kb
+#
+#   gas_price = <bytes>
+#
+#       The gas price is the conversion between WASM gas and its price in drops.
+#
+#       If this parameter is unspecified, xrpld will use an internal
+#       default. Don't change this without understanding the consequences.
+#
+#       Example:
+#           gas_price = 1000000      # 1 drop per gas
 #-------------------------------------------------------------------------------
 #
 # 9. Misc Settings

cmake/XrplCore.cmake

@@ -67,6 +67,7 @@ target_link_libraries(
         Xrpl::opts
         Xrpl::syslibs
         secp256k1::secp256k1
+        wasmi::wasmi
         xrpl.libpb
         xxHash::xxhash
         $<$<BOOL:${voidstar}>:antithesis-sdk-cpp>

conan.lock

@@ -3,6 +3,7 @@
     "requires": [
         "zlib/1.3.1#b8bc2603263cf7eccbd6e17e66b0ed76%1765850150.075",
         "xxhash/0.8.3#681d36a0a6111fc56e5e45ea182c19cc%1765850149.987",
+        "wasmi/1.0.6#407c9db14601a8af1c7dd3b388f3e4cd%1768164779.349",
         "sqlite3/3.49.1#8631739a4c9b93bd3d6b753bac548a63%1765850149.926",
         "soci/4.0.3#a9f8d773cd33e356b5879a4b0564f287%1765850149.46",
         "snappy/1.1.10#968fef506ff261592ec30c574d4a7809%1765850147.878",

conanfile.py

@@ -36,6 +36,7 @@ class Xrpl(ConanFile):
         "openssl/3.5.5",
         "secp256k1/0.7.1",
         "soci/4.0.3",
+        "wasmi/1.0.6",
         "zlib/1.3.1",
     ]
 
@@ -225,6 +226,7 @@ class Xrpl(ConanFile):
             "soci::soci",
             "secp256k1::secp256k1",
             "sqlite3::sqlite",
+            "wasmi::wasmi",
             "xxhash::xxhash",
             "zlib::zlib",
         ]

cspell.config.yaml

@@ -7,6 +7,8 @@ ignorePaths:
   - cmake/**
   - LICENSE.md
   - .clang-tidy
+  - src/test/app/wasm_fixtures/**/*.wat
+  - src/test/app/wasm_fixtures/*.c
 language: en
 allowCompoundWords: true # TODO (#6334)
 ignoreRandomStrings: true
@@ -60,6 +62,7 @@ words:
   - Britto
   - Btrfs
   - canonicality
+  - cdylib
   - changespq
   - checkme
   - choco
@@ -297,6 +300,7 @@ words:
   - venv
   - vfalco
   - vinnie
+  - wasmi
   - wextra
   - wptr
   - writeme

include/xrpl/basics/Number.h

@@ -729,6 +729,10 @@ abs(Number x) noexcept
 Number
 power(Number const& f, unsigned n);
 
+// logarithm with base 10
+Number
+log10(Number const& value, int iterations = 50);
+
 // Returns f^(1/d)
 // Uses Newton–Raphson iterations until the result stops changing
 // to find the root of the polynomial g(x) = x^d - f

include/xrpl/core/ServiceRegistry.h

@@ -4,6 +4,7 @@
 #include <xrpl/basics/SHAMapHash.h>
 #include <xrpl/basics/TaggedCache.h>
 #include <xrpl/ledger/CachedSLEs.h>
+#include <xrpl/protocol/Fees.h>
 
 #include <boost/asio.hpp>
 
@@ -225,6 +226,9 @@ public:
     virtual DatabaseCon&
     getWalletDB() = 0;
 
+    virtual Fees
+    getFees() const = 0;
+
     // Temporary: Get the underlying Application for functions that haven't
     // been migrated yet. This should be removed once all code is migrated.
     virtual Application&

include/xrpl/ledger/ApplyViewImpl.h

@@ -54,6 +54,18 @@ public:
         deliver_ = amount;
     }
 
+    void
+    setGasUsed(std::optional<std::uint32_t> const gasUsed)
+    {
+        gasUsed_ = gasUsed;
+    }
+
+    void
+    setWasmReturnCode(std::int32_t const wasmReturnCode)
+    {
+        wasmReturnCode_ = wasmReturnCode;
+    }
+
     /** Get the number of modified entries
      */
     std::size_t
@@ -72,6 +84,8 @@ public:
 
 private:
     std::optional<STAmount> deliver_;
+    std::optional<std::uint32_t> gasUsed_;
+    std::optional<std::int32_t> wasmReturnCode_;
 };
 
 }  // namespace xrpl

include/xrpl/ledger/Credit.h

@@ -1,43 +0,0 @@
-#pragma once
-
-#include <xrpl/ledger/View.h>
-#include <xrpl/protocol/IOUAmount.h>
-#include <xrpl/protocol/STAmount.h>
-
-namespace xrpl {
-
-/** Calculate the maximum amount of IOUs that an account can hold
-    @param ledger the ledger to check against.
-    @param account the account of interest.
-    @param issuer the issuer of the IOU.
-    @param currency the IOU to check.
-    @return The maximum amount that can be held.
-*/
-/** @{ */
-STAmount
-creditLimit(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency);
-
-IOUAmount
-creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur);
-/** @} */
-
-/** Returns the amount of IOUs issued by issuer that are held by an account
-    @param ledger the ledger to check against.
-    @param account the account of interest.
-    @param issuer the issuer of the IOU.
-    @param currency the IOU to check.
-*/
-/** @{ */
-STAmount
-creditBalance(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency);
-/** @} */
-
-}  // namespace xrpl

include/xrpl/ledger/View.h

@@ -2,26 +2,23 @@
 
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/OpenView.h>
 #include <xrpl/ledger/ReadView.h>
-#include <xrpl/protocol/Asset.h>
-#include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/MPTIssue.h>
 #include <xrpl/protocol/Protocol.h>
-#include <xrpl/protocol/Rate.h>
 #include <xrpl/protocol/STLedgerEntry.h>
-#include <xrpl/protocol/STObject.h>
-#include <xrpl/protocol/Serializer.h>
+#include <xrpl/protocol/STTx.h>
 #include <xrpl/protocol/TER.h>
 
+#include <cstdint>
 #include <functional>
-#include <initializer_list>
 #include <map>
+#include <memory>
+#include <optional>
+#include <set>
 #include <utility>
 
 namespace xrpl {
 
-enum class WaiveTransferFee : bool { No = false, Yes };
 enum class SkipEntry : bool { No = false, Yes };
 
 //------------------------------------------------------------------------------
@@ -54,24 +51,6 @@ enum class SkipEntry : bool { No = false, Yes };
 [[nodiscard]] bool
 hasExpired(ReadView const& view, std::optional<std::uint32_t> const& exp);
 
-/** Controls the treatment of frozen account balances */
-enum FreezeHandling { fhIGNORE_FREEZE, fhZERO_IF_FROZEN };
-
-/** Controls the treatment of unauthorized MPT balances */
-enum AuthHandling { ahIGNORE_AUTH, ahZERO_IF_UNAUTHORIZED };
-
-/** Controls whether to include the account's full spendable balance */
-enum SpendableHandling { shSIMPLE_BALANCE, shFULL_BALANCE };
-
-[[nodiscard]] bool
-isGlobalFrozen(ReadView const& view, AccountID const& issuer);
-
-[[nodiscard]] bool
-isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue);
-
-[[nodiscard]] bool
-isGlobalFrozen(ReadView const& view, Asset const& asset);
-
 // Note, depth parameter is used to limit the recursion depth
 [[nodiscard]] bool
 isVaultPseudoAccountFrozen(
@@ -80,175 +59,6 @@ isVaultPseudoAccountFrozen(
     MPTIssue const& mptShare,
     int depth);
 
-[[nodiscard]] bool
-isIndividualFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer);
-
-[[nodiscard]] inline bool
-isIndividualFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
-{
-    return isIndividualFrozen(view, account, issue.currency, issue.account);
-}
-
-[[nodiscard]] bool
-isIndividualFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
-
-[[nodiscard]] inline bool
-isIndividualFrozen(ReadView const& view, AccountID const& account, Asset const& asset)
-{
-    return std::visit(
-        [&](auto const& issue) { return isIndividualFrozen(view, account, issue); }, asset.value());
-}
-
-[[nodiscard]] bool
-isFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer);
-
-[[nodiscard]] inline bool
-isFrozen(ReadView const& view, AccountID const& account, Issue const& issue, int = 0 /*ignored*/)
-{
-    return isFrozen(view, account, issue.currency, issue.account);
-}
-
-[[nodiscard]] bool
-isFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue, int depth = 0);
-
-/**
- *   isFrozen check is recursive for MPT shares in a vault, descending to
- *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
- *   purely defensive, as we currently do not allow such vaults to be created.
- */
-[[nodiscard]] inline bool
-isFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0)
-{
-    return std::visit(
-        [&](auto const& issue) { return isFrozen(view, account, issue, depth); }, asset.value());
-}
-
-[[nodiscard]] inline TER
-checkFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
-{
-    return isFrozen(view, account, issue) ? (TER)tecFROZEN : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue)
-{
-    return isFrozen(view, account, mptIssue) ? (TER)tecLOCKED : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkFrozen(ReadView const& view, AccountID const& account, Asset const& asset)
-{
-    return std::visit(
-        [&](auto const& issue) { return checkFrozen(view, account, issue); }, asset.value());
-}
-
-[[nodiscard]] bool
-isAnyFrozen(
-    ReadView const& view,
-    std::initializer_list<AccountID> const& accounts,
-    MPTIssue const& mptIssue,
-    int depth = 0);
-
-[[nodiscard]] inline bool
-isAnyFrozen(
-    ReadView const& view,
-    std::initializer_list<AccountID> const& accounts,
-    Issue const& issue)
-{
-    for (auto const& account : accounts)
-    {
-        if (isFrozen(view, account, issue.currency, issue.account))
-            return true;
-    }
-    return false;
-}
-
-[[nodiscard]] inline bool
-isAnyFrozen(
-    ReadView const& view,
-    std::initializer_list<AccountID> const& accounts,
-    Asset const& asset,
-    int depth = 0)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) {
-            if constexpr (std::is_same_v<TIss, Issue>)
-                return isAnyFrozen(view, accounts, issue);
-            else
-                return isAnyFrozen(view, accounts, issue, depth);
-        },
-        asset.value());
-}
-
-[[nodiscard]] bool
-isDeepFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer);
-
-[[nodiscard]] inline bool
-isDeepFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Issue const& issue,
-    int = 0 /*ignored*/)
-{
-    return isDeepFrozen(view, account, issue.currency, issue.account);
-}
-
-[[nodiscard]] inline bool
-isDeepFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    MPTIssue const& mptIssue,
-    int depth = 0)
-{
-    // Unlike IOUs, frozen / locked MPTs are not allowed to send or receive
-    // funds, so checking "deep frozen" is the same as checking "frozen".
-    return isFrozen(view, account, mptIssue, depth);
-}
-
-/**
- *   isFrozen check is recursive for MPT shares in a vault, descending to
- *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
- *   purely defensive, as we currently do not allow such vaults to be created.
- */
-[[nodiscard]] inline bool
-isDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0)
-{
-    return std::visit(
-        [&](auto const& issue) { return isDeepFrozen(view, account, issue, depth); },
-        asset.value());
-}
-
-[[nodiscard]] inline TER
-checkDeepFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
-{
-    return isDeepFrozen(view, account, issue) ? (TER)tecFROZEN : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkDeepFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue)
-{
-    return isDeepFrozen(view, account, mptIssue) ? (TER)tecLOCKED : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset)
-{
-    return std::visit(
-        [&](auto const& issue) { return checkDeepFrozen(view, account, issue); }, asset.value());
-}
-
 [[nodiscard]] bool
 isLPTokenFrozen(
     ReadView const& view,
@@ -256,159 +66,6 @@ isLPTokenFrozen(
     Issue const& asset,
     Issue const& asset2);
 
-// Returns the amount an account can spend.
-//
-// If shSIMPLE_BALANCE is specified, this is the amount the account can spend
-// without going into debt.
-//
-// If shFULL_BALANCE is specified, this is the amount the account can spend
-// total. Specifically:
-// * The account can go into debt if using a trust line, and the other side has
-// a non-zero limit.
-// * If the account is the asset issuer the limit is defined by the asset /
-//   issuance.
-//
-// <-- saAmount: amount of currency held by account. May be negative.
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer,
-    FreezeHandling zeroIfFrozen,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    Issue const& issue,
-    FreezeHandling zeroIfFrozen,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    MPTIssue const& mptIssue,
-    FreezeHandling zeroIfFrozen,
-    AuthHandling zeroIfUnauthorized,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    Asset const& asset,
-    FreezeHandling zeroIfFrozen,
-    AuthHandling zeroIfUnauthorized,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-// Returns the amount an account can spend of the currency type saDefault, or
-// returns saDefault if this account is the issuer of the currency in
-// question. Should be used in favor of accountHolds when questioning how much
-// an account can spend while also allowing currency issuers to spend
-// unlimited amounts of their own currency (since they can always issue more).
-[[nodiscard]] STAmount
-accountFunds(
-    ReadView const& view,
-    AccountID const& id,
-    STAmount const& saDefault,
-    FreezeHandling freezeHandling,
-    beast::Journal j);
-
-// Return the account's liquid (not reserved) XRP.  Generally prefer
-// calling accountHolds() over this interface.  However, this interface
-// allows the caller to temporarily adjust the owner count should that be
-// necessary.
-//
-// @param ownerCountAdj positive to add to count, negative to reduce count.
-[[nodiscard]] XRPAmount
-xrpLiquid(ReadView const& view, AccountID const& id, std::int32_t ownerCountAdj, beast::Journal j);
-
-/** Iterate all items in the given directory. */
-void
-forEachItem(
-    ReadView const& view,
-    Keylet const& root,
-    std::function<void(std::shared_ptr<SLE const> const&)> const& f);
-
-/** Iterate all items after an item in the given directory.
-    @param after The key of the item to start after
-    @param hint The directory page containing `after`
-    @param limit The maximum number of items to return
-    @return `false` if the iteration failed
-*/
-bool
-forEachItemAfter(
-    ReadView const& view,
-    Keylet const& root,
-    uint256 const& after,
-    std::uint64_t const hint,
-    unsigned int limit,
-    std::function<bool(std::shared_ptr<SLE const> const&)> const& f);
-
-/** Iterate all items in an account's owner directory. */
-inline void
-forEachItem(
-    ReadView const& view,
-    AccountID const& id,
-    std::function<void(std::shared_ptr<SLE const> const&)> const& f)
-{
-    return forEachItem(view, keylet::ownerDir(id), f);
-}
-
-/** Iterate all items after an item in an owner directory.
-    @param after The key of the item to start after
-    @param hint The directory page containing `after`
-    @param limit The maximum number of items to return
-    @return `false` if the iteration failed
-*/
-inline bool
-forEachItemAfter(
-    ReadView const& view,
-    AccountID const& id,
-    uint256 const& after,
-    std::uint64_t const hint,
-    unsigned int limit,
-    std::function<bool(std::shared_ptr<SLE const> const&)> const& f)
-{
-    return forEachItemAfter(view, keylet::ownerDir(id), after, hint, limit, f);
-}
-
-/** Returns IOU issuer transfer fee as Rate. Rate specifies
- * the fee as fractions of 1 billion. For example, 1% transfer rate
- * is represented as 1,010,000,000.
- * @param issuer The IOU issuer
- */
-[[nodiscard]] Rate
-transferRate(ReadView const& view, AccountID const& issuer);
-
-/** Returns MPT transfer fee as Rate. Rate specifies
- * the fee as fractions of 1 billion. For example, 1% transfer rate
- * is represented as 1,010,000,000.
- * @param issuanceID MPTokenIssuanceID of MPTTokenIssuance object
- */
-[[nodiscard]] Rate
-transferRate(ReadView const& view, MPTID const& issuanceID);
-
-/** Returns the transfer fee as Rate based on the type of token
- * @param view The ledger view
- * @param amount The amount to transfer
- */
-[[nodiscard]] Rate
-transferRate(ReadView const& view, STAmount const& amount);
-
-/** Returns `true` if the directory is empty
-    @param key The key of the directory
-*/
-[[nodiscard]] bool
-dirIsEmpty(ReadView const& view, Keylet const& k);
-
 // Return the list of enabled amendments
 [[nodiscard]] std::set<uint256>
 getEnabledAmendments(ReadView const& view);
@@ -474,81 +131,6 @@ areCompatible(
 //
 //------------------------------------------------------------------------------
 
-/** Adjust the owner count up or down. */
-void
-adjustOwnerCount(
-    ApplyView& view,
-    std::shared_ptr<SLE> const& sle,
-    std::int32_t amount,
-    beast::Journal j);
-
-/** @{ */
-/** Returns the first entry in the directory, advancing the index
-
-    @deprecated These are legacy function that are considered deprecated
-                and will soon be replaced with an iterator-based model
-                that is easier to use. You should not use them in new code.
-
-    @param view The view against which to operate
-    @param root The root (i.e. first page) of the directory to iterate
-    @param page The current page
-    @param index The index inside the current page
-    @param entry The entry at the current index
-
-    @return true if the directory isn't empty; false otherwise
- */
-bool
-cdirFirst(
-    ReadView const& view,
-    uint256 const& root,
-    std::shared_ptr<SLE const>& page,
-    unsigned int& index,
-    uint256& entry);
-
-bool
-dirFirst(
-    ApplyView& view,
-    uint256 const& root,
-    std::shared_ptr<SLE>& page,
-    unsigned int& index,
-    uint256& entry);
-/** @} */
-
-/** @{ */
-/** Returns the next entry in the directory, advancing the index
-
-    @deprecated These are legacy function that are considered deprecated
-                and will soon be replaced with an iterator-based model
-                that is easier to use. You should not use them in new code.
-
-    @param view The view against which to operate
-    @param root The root (i.e. first page) of the directory to iterate
-    @param page The current page
-    @param index The index inside the current page
-    @param entry The entry at the current index
-
-    @return true if the directory isn't empty; false otherwise
- */
-bool
-cdirNext(
-    ReadView const& view,
-    uint256 const& root,
-    std::shared_ptr<SLE const>& page,
-    unsigned int& index,
-    uint256& entry);
-
-bool
-dirNext(
-    ApplyView& view,
-    uint256 const& root,
-    std::shared_ptr<SLE>& page,
-    unsigned int& index,
-    uint256& entry);
-/** @} */
-
-[[nodiscard]] std::function<void(SLE::ref)>
-describeOwnerDir(AccountID const& account);
-
 [[nodiscard]] TER
 dirLink(
     ApplyView& view,
@@ -556,63 +138,6 @@ dirLink(
     std::shared_ptr<SLE>& object,
     SF_UINT64 const& node = sfOwnerNode);
 
-AccountID
-pseudoAccountAddress(ReadView const& view, uint256 const& pseudoOwnerKey);
-
-/**
- *
- * Create pseudo-account, storing pseudoOwnerKey into ownerField.
- *
- * The list of valid ownerField is maintained in View.cpp and the caller to
- * this function must perform necessary amendment check(s) before using a
- * field. The amendment check is **not** performed in createPseudoAccount.
- */
-[[nodiscard]] Expected<std::shared_ptr<SLE>, TER>
-createPseudoAccount(ApplyView& view, uint256 const& pseudoOwnerKey, SField const& ownerField);
-
-// Returns true if and only if sleAcct is a pseudo-account or specific
-// pseudo-accounts in pseudoFieldFilter.
-//
-// Returns false if sleAcct is
-// * NOT a pseudo-account OR
-// * NOT a ltACCOUNT_ROOT OR
-// * null pointer
-[[nodiscard]] bool
-isPseudoAccount(
-    std::shared_ptr<SLE const> sleAcct,
-    std::set<SField const*> const& pseudoFieldFilter = {});
-
-// Returns the list of fields that define an ACCOUNT_ROOT as a pseudo-account if
-// set
-// Pseudo-account designator fields MUST be maintained by including the
-// SField::sMD_PseudoAccount flag in the SField definition. (Don't forget to
-// "| SField::sMD_Default"!) The fields do NOT need to be amendment-gated,
-// since a non-active amendment will not set any field, by definition.
-// Specific properties of a pseudo-account are NOT checked here, that's what
-// InvariantCheck is for.
-[[nodiscard]] std::vector<SField const*> const&
-getPseudoAccountFields();
-
-[[nodiscard]] inline bool
-isPseudoAccount(
-    ReadView const& view,
-    AccountID const& accountId,
-    std::set<SField const*> const& pseudoFieldFilter = {})
-{
-    return isPseudoAccount(view.read(keylet::account(accountId)), pseudoFieldFilter);
-}
-
-[[nodiscard]] TER
-canAddHolding(ReadView const& view, Asset const& asset);
-
-/** Validates that the destination SLE and tag are valid
-
-   - Checks that the SLE is not null.
-   - If the SLE requires a destination tag, checks that there is a tag.
-*/
-[[nodiscard]] TER
-checkDestinationAndTag(SLE::const_ref toSle, bool hasDestinationTag);
-
 /** Checks that can withdraw funds from an object to itself or a destination.
  *
  * The receiver may be either the submitting account (sfAccount) or a different
@@ -686,351 +211,6 @@ doWithdraw(
     STAmount const& amount,
     beast::Journal j);
 
-/// Any transactors that call addEmptyHolding() in doApply must call
-/// canAddHolding() in preflight with the same View and Asset
-[[nodiscard]] TER
-addEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    XRPAmount priorBalance,
-    Issue const& issue,
-    beast::Journal journal);
-
-[[nodiscard]] TER
-addEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    XRPAmount priorBalance,
-    MPTIssue const& mptIssue,
-    beast::Journal journal);
-
-[[nodiscard]] inline TER
-addEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    XRPAmount priorBalance,
-    Asset const& asset,
-    beast::Journal journal)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
-            return addEmptyHolding(view, accountID, priorBalance, issue, journal);
-        },
-        asset.value());
-}
-
-[[nodiscard]] TER
-authorizeMPToken(
-    ApplyView& view,
-    XRPAmount const& priorBalance,
-    MPTID const& mptIssuanceID,
-    AccountID const& account,
-    beast::Journal journal,
-    std::uint32_t flags = 0,
-    std::optional<AccountID> holderID = std::nullopt);
-
-// VFALCO NOTE Both STAmount parameters should just
-//             be "Amount", a unit-less number.
-//
-/** Create a trust line
-
-    This can set an initial balance.
-*/
-[[nodiscard]] TER
-trustCreate(
-    ApplyView& view,
-    bool const bSrcHigh,
-    AccountID const& uSrcAccountID,
-    AccountID const& uDstAccountID,
-    uint256 const& uIndex,      // --> ripple state entry
-    SLE::ref sleAccount,        // --> the account being set.
-    bool const bAuth,           // --> authorize account.
-    bool const bNoRipple,       // --> others cannot ripple through
-    bool const bFreeze,         // --> funds cannot leave
-    bool bDeepFreeze,           // --> can neither receive nor send funds
-    STAmount const& saBalance,  // --> balance of account being set.
-                                // Issuer should be noAccount()
-    STAmount const& saLimit,    // --> limit for account being set.
-                                // Issuer should be the account being set.
-    std::uint32_t uSrcQualityIn,
-    std::uint32_t uSrcQualityOut,
-    beast::Journal j);
-
-[[nodiscard]] TER
-removeEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    Issue const& issue,
-    beast::Journal journal);
-
-[[nodiscard]] TER
-removeEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    MPTIssue const& mptIssue,
-    beast::Journal journal);
-
-[[nodiscard]] inline TER
-removeEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    Asset const& asset,
-    beast::Journal journal)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
-            return removeEmptyHolding(view, accountID, issue, journal);
-        },
-        asset.value());
-}
-
-[[nodiscard]] TER
-trustDelete(
-    ApplyView& view,
-    std::shared_ptr<SLE> const& sleRippleState,
-    AccountID const& uLowAccountID,
-    AccountID const& uHighAccountID,
-    beast::Journal j);
-
-/** Delete an offer.
-
-    Requirements:
-        The passed `sle` be obtained from a prior
-        call to view.peek()
-*/
-// [[nodiscard]] // nodiscard commented out so Flow, BookTip and others compile.
-TER
-offerDelete(ApplyView& view, std::shared_ptr<SLE> const& sle, beast::Journal j);
-
-//------------------------------------------------------------------------------
-
-//
-// Money Transfers
-//
-
-// Direct send w/o fees:
-// - Redeeming IOUs and/or sending sender's own IOUs.
-// - Create trust line of needed.
-// --> bCheckIssuer : normally require issuer to be involved.
-// [[nodiscard]] // nodiscard commented out so DirectStep.cpp compiles.
-
-/** Calls static rippleCreditIOU if saAmount represents Issue.
- * Calls static rippleCreditMPT if saAmount represents MPTIssue.
- */
-TER
-rippleCredit(
-    ApplyView& view,
-    AccountID const& uSenderID,
-    AccountID const& uReceiverID,
-    STAmount const& saAmount,
-    bool bCheckIssuer,
-    beast::Journal j);
-
-TER
-rippleLockEscrowMPT(
-    ApplyView& view,
-    AccountID const& uGrantorID,
-    STAmount const& saAmount,
-    beast::Journal j);
-
-TER
-rippleUnlockEscrowMPT(
-    ApplyView& view,
-    AccountID const& uGrantorID,
-    AccountID const& uGranteeID,
-    STAmount const& netAmount,
-    STAmount const& grossAmount,
-    beast::Journal j);
-
-/** Calls static accountSendIOU if saAmount represents Issue.
- * Calls static accountSendMPT if saAmount represents MPTIssue.
- */
-[[nodiscard]] TER
-accountSend(
-    ApplyView& view,
-    AccountID const& from,
-    AccountID const& to,
-    STAmount const& saAmount,
-    beast::Journal j,
-    WaiveTransferFee waiveFee = WaiveTransferFee::No);
-
-using MultiplePaymentDestinations = std::vector<std::pair<AccountID, Number>>;
-/** Like accountSend, except one account is sending multiple payments (with the
- *  same asset!) simultaneously
- *
- * Calls static accountSendMultiIOU if saAmount represents Issue.
- * Calls static accountSendMultiMPT if saAmount represents MPTIssue.
- */
-[[nodiscard]] TER
-accountSendMulti(
-    ApplyView& view,
-    AccountID const& senderID,
-    Asset const& asset,
-    MultiplePaymentDestinations const& receivers,
-    beast::Journal j,
-    WaiveTransferFee waiveFee = WaiveTransferFee::No);
-
-[[nodiscard]] TER
-issueIOU(
-    ApplyView& view,
-    AccountID const& account,
-    STAmount const& amount,
-    Issue const& issue,
-    beast::Journal j);
-
-[[nodiscard]] TER
-redeemIOU(
-    ApplyView& view,
-    AccountID const& account,
-    STAmount const& amount,
-    Issue const& issue,
-    beast::Journal j);
-
-[[nodiscard]] TER
-transferXRP(
-    ApplyView& view,
-    AccountID const& from,
-    AccountID const& to,
-    STAmount const& amount,
-    beast::Journal j);
-
-/* Check if MPToken (for MPT) or trust line (for IOU) exists:
- * - StrongAuth - before checking if authorization is required
- * - WeakAuth
- *    for MPT - after checking lsfMPTRequireAuth flag
- *    for IOU - do not check if trust line exists
- * - Legacy
- *    for MPT - before checking lsfMPTRequireAuth flag i.e. same as StrongAuth
- *    for IOU - do not check if trust line exists i.e. same as WeakAuth
- */
-enum class AuthType { StrongAuth, WeakAuth, Legacy };
-
-/** Check if the account lacks required authorization.
- *
- * Return tecNO_AUTH or tecNO_LINE if it does
- * and tesSUCCESS otherwise.
- *
- * If StrongAuth then return tecNO_LINE if the RippleState doesn't exist. Return
- * tecNO_AUTH if lsfRequireAuth is set on the issuer's AccountRoot, and the
- * RippleState does exist, and the RippleState is not authorized.
- *
- * If WeakAuth then return tecNO_AUTH if lsfRequireAuth is set, and the
- * RippleState exists, and is not authorized. Return tecNO_LINE if
- * lsfRequireAuth is set and the RippleState doesn't exist. Consequently, if
- * WeakAuth and lsfRequireAuth is *not* set, this function will return
- * tesSUCCESS even if RippleState does *not* exist.
- *
- * The default "Legacy" auth type is equivalent to WeakAuth.
- */
-[[nodiscard]] TER
-requireAuth(
-    ReadView const& view,
-    Issue const& issue,
-    AccountID const& account,
-    AuthType authType = AuthType::Legacy);
-
-/** Check if the account lacks required authorization.
- *
- * This will also check for expired credentials. If it is called directly
- * from preclaim, the user should convert result tecEXPIRED to tesSUCCESS and
- * proceed to also check permissions with enforceMPTokenAuthorization inside
- * doApply. This will ensure that any expired credentials are deleted.
- *
- * requireAuth check is recursive for MPT shares in a vault, descending to
- * assets in the vault, up to maxAssetCheckDepth recursion depth. This is
- * purely defensive, as we currently do not allow such vaults to be created.
- *
- * If StrongAuth then return tecNO_AUTH if MPToken doesn't exist or
- * lsfMPTRequireAuth is set and MPToken is not authorized. Vault and LoanBroker
- * pseudo-accounts are implicitly authorized.
- *
- * If WeakAuth then return tecNO_AUTH if lsfMPTRequireAuth is set and MPToken
- * doesn't exist or is not authorized (explicitly or via credentials, if
- * DomainID is set in MPTokenIssuance). Consequently, if WeakAuth and
- * lsfMPTRequireAuth is *not* set, this function will return true even if
- * MPToken does *not* exist.
- *
- * The default "Legacy" auth type is equivalent to StrongAuth.
- */
-[[nodiscard]] TER
-requireAuth(
-    ReadView const& view,
-    MPTIssue const& mptIssue,
-    AccountID const& account,
-    AuthType authType = AuthType::Legacy,
-    int depth = 0);
-
-[[nodiscard]] TER inline requireAuth(
-    ReadView const& view,
-    Asset const& asset,
-    AccountID const& account,
-    AuthType authType = AuthType::Legacy)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue_) {
-            return requireAuth(view, issue_, account, authType);
-        },
-        asset.value());
-}
-
-/** Enforce account has MPToken to match its authorization.
- *
- *   Called from doApply - it will check for expired (and delete if found any)
- *   credentials matching DomainID set in MPTokenIssuance. Must be called if
- *   requireAuth(...MPTIssue...) returned tesSUCCESS or tecEXPIRED in preclaim,
- *   which implies that preclaim should replace `tecEXPIRED` with `tesSUCCESS`
- *   in order for the transactor to proceed to doApply.
- *
- *   This function will create MPToken (if needed) on the basis of any
- *   non-expired credentials and will delete any expired credentials, indirectly
- *   via verifyValidDomain, as per DomainID (if set in MPTokenIssuance).
- *
- *   The caller does NOT need to ensure that DomainID is actually set - this
- *   function handles gracefully both cases when DomainID is set and when not.
- *
- *   The caller does NOT need to look for existing MPToken to match
- *   mptIssue/account - this function checks lsfMPTAuthorized of an existing
- *   MPToken iff DomainID is not set.
- *
- *   Do not use for accounts which hold implied permission e.g. object owners or
- *   if MPTokenIssuance does not require authorization. In both cases use
- *   MPTokenAuthorize::authorize if MPToken does not yet exist.
- */
-[[nodiscard]] TER
-enforceMPTokenAuthorization(
-    ApplyView& view,
-    MPTID const& mptIssuanceID,
-    AccountID const& account,
-    XRPAmount const& priorBalance,
-    beast::Journal j);
-
-/** Check if the destination account is allowed
- *  to receive MPT. Return tecNO_AUTH if it doesn't
- *  and tesSUCCESS otherwise.
- */
-[[nodiscard]] TER
-canTransfer(
-    ReadView const& view,
-    MPTIssue const& mptIssue,
-    AccountID const& from,
-    AccountID const& to);
-
-[[nodiscard]] TER
-canTransfer(ReadView const& view, Issue const& issue, AccountID const& from, AccountID const& to);
-
-[[nodiscard]] TER inline canTransfer(
-    ReadView const& view,
-    Asset const& asset,
-    AccountID const& from,
-    AccountID const& to)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
-            return canTransfer(view, issue, from, to);
-        },
-        asset.value());
-}
-
 /** Deleter function prototype. Returns the status of the entry deletion
  * (if should not be skipped) and if the entry should be skipped. The status
  * is always tesSUCCESS if the entry should be skipped.
@@ -1052,57 +232,6 @@ cleanupOnAccountDelete(
     beast::Journal j,
     std::optional<std::uint16_t> maxNodesToDelete = std::nullopt);
 
-/** Delete trustline to AMM. The passed `sle` must be obtained from a prior
- * call to view.peek(). Fail if neither side of the trustline is AMM or
- * if ammAccountID is seated and is not one of the trustline's side.
- */
-[[nodiscard]] TER
-deleteAMMTrustLine(
-    ApplyView& view,
-    std::shared_ptr<SLE> sleState,
-    std::optional<AccountID> const& ammAccountID,
-    beast::Journal j);
-
-// From the perspective of a vault, return the number of shares to give the
-// depositor when they deposit a fixed amount of assets. Since shares are MPT
-// this number is integral and always truncated in this calculation.
-[[nodiscard]] std::optional<STAmount>
-assetsToSharesDeposit(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& assets);
-
-// From the perspective of a vault, return the number of assets to take from
-// depositor when they receive a fixed amount of shares. Note, since shares are
-// MPT, they are always an integral number.
-[[nodiscard]] std::optional<STAmount>
-sharesToAssetsDeposit(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& shares);
-
-enum class TruncateShares : bool { no = false, yes = true };
-
-// From the perspective of a vault, return the number of shares to demand from
-// the depositor when they ask to withdraw a fixed amount of assets. Since
-// shares are MPT this number is integral, and it will be rounded to nearest
-// unless explicitly requested to be truncated instead.
-[[nodiscard]] std::optional<STAmount>
-assetsToSharesWithdraw(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& assets,
-    TruncateShares truncate = TruncateShares::no);
-
-// From the perspective of a vault, return the number of assets to give the
-// depositor when they redeem a fixed amount of shares. Note, since shares are
-// MPT, they are always an integral number.
-[[nodiscard]] std::optional<STAmount>
-sharesToAssetsWithdraw(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& shares);
-
 /** Has the specified time passed?
 
     @param now  the current time

include/xrpl/ledger/detail/ApplyStateTable.h

@@ -52,6 +52,8 @@ public:
         TER ter,
         std::optional<STAmount> const& deliver,
         std::optional<uint256 const> const& parentBatchId,
+        std::optional<std::uint32_t> const& gasUsed,
+        std::optional<std::int32_t> const& wasmReturnCode,
         bool isDryRun,
         beast::Journal j);
 

include/xrpl/ledger/helpers/AccountRootHelpers.h

@@ -0,0 +1,112 @@
+#pragma once
+
+#include <xrpl/basics/Expected.h>
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Rate.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+#include <memory>
+#include <set>
+#include <vector>
+
+namespace xrpl {
+
+/** Check if the issuer has the global freeze flag set.
+    @param issuer The account to check
+    @return true if the account has global freeze set
+*/
+[[nodiscard]] bool
+isGlobalFrozen(ReadView const& view, AccountID const& issuer);
+
+// Calculate liquid XRP balance for an account.
+// This function may be used to calculate the amount of XRP that
+// the holder is able to freely spend. It subtracts reserve requirements.
+//
+// ownerCountAdj adjusts the owner count in case the caller calculates
+// before ledger entries are added or removed. Positive to add, negative
+// to subtract.
+//
+// @param ownerCountAdj positive to add to count, negative to reduce count.
+[[nodiscard]] XRPAmount
+xrpLiquid(ReadView const& view, AccountID const& id, std::int32_t ownerCountAdj, beast::Journal j);
+
+/** Adjust the owner count up or down. */
+void
+adjustOwnerCount(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sle,
+    std::int32_t amount,
+    beast::Journal j);
+
+/** Returns IOU issuer transfer fee as Rate. Rate specifies
+ * the fee as fractions of 1 billion. For example, 1% transfer rate
+ * is represented as 1,010,000,000.
+ * @param issuer The IOU issuer
+ */
+[[nodiscard]] Rate
+transferRate(ReadView const& view, AccountID const& issuer);
+
+/** Generate a pseudo-account address from a pseudo owner key.
+    @param pseudoOwnerKey The key to generate the address from
+    @return The generated account ID
+*/
+AccountID
+pseudoAccountAddress(ReadView const& view, uint256 const& pseudoOwnerKey);
+
+/** Returns the list of fields that define an ACCOUNT_ROOT as a pseudo-account
+    if set.
+
+    The list is constructed during initialization and is const after that.
+    Pseudo-account designator fields MUST be maintained by including the
+    SField::sMD_PseudoAccount flag in the SField definition.
+*/
+[[nodiscard]] std::vector<SField const*> const&
+getPseudoAccountFields();
+
+/** Returns true if and only if sleAcct is a pseudo-account or specific
+    pseudo-accounts in pseudoFieldFilter.
+
+    Returns false if sleAcct is:
+    - NOT a pseudo-account OR
+    - NOT a ltACCOUNT_ROOT OR
+    - null pointer
+*/
+[[nodiscard]] bool
+isPseudoAccount(
+    std::shared_ptr<SLE const> sleAcct,
+    std::set<SField const*> const& pseudoFieldFilter = {});
+
+/** Convenience overload that reads the account from the view. */
+[[nodiscard]] inline bool
+isPseudoAccount(
+    ReadView const& view,
+    AccountID const& accountId,
+    std::set<SField const*> const& pseudoFieldFilter = {})
+{
+    return isPseudoAccount(view.read(keylet::account(accountId)), pseudoFieldFilter);
+}
+
+/**
+ * Create pseudo-account, storing pseudoOwnerKey into ownerField.
+ *
+ * The list of valid ownerField is maintained in AccountRootHelpers.cpp and
+ * the caller to this function must perform necessary amendment check(s)
+ * before using a field. The amendment check is **not** performed in
+ * createPseudoAccount.
+ */
+[[nodiscard]] Expected<std::shared_ptr<SLE>, TER>
+createPseudoAccount(ApplyView& view, uint256 const& pseudoOwnerKey, SField const& ownerField);
+
+/** Checks the destination and tag.
+
+   - Checks that the SLE is not null.
+   - If the SLE requires a destination tag, checks that there is a tag.
+*/
+[[nodiscard]] TER
+checkDestinationAndTag(SLE::const_ref toSle, bool hasDestinationTag);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/DirectoryHelpers.h

@@ -0,0 +1,223 @@
+#pragma once
+
+#include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+#include <functional>
+#include <memory>
+#include <type_traits>
+
+namespace xrpl {
+
+namespace detail {
+
+template <
+    class V,
+    class N,
+    class = std::enable_if_t<
+        std::is_same_v<std::remove_cv_t<N>, SLE> && std::is_base_of_v<ReadView, V>>>
+bool
+internalDirNext(
+    V& view,
+    uint256 const& root,
+    std::shared_ptr<N>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    auto const& svIndexes = page->getFieldV256(sfIndexes);
+    XRPL_ASSERT(index <= svIndexes.size(), "xrpl::detail::internalDirNext : index inside range");
+
+    if (index >= svIndexes.size())
+    {
+        auto const next = page->getFieldU64(sfIndexNext);
+
+        if (!next)
+        {
+            entry.zero();
+            return false;
+        }
+
+        if constexpr (std::is_const_v<N>)
+        {
+            page = view.read(keylet::page(root, next));
+        }
+        else
+        {
+            page = view.peek(keylet::page(root, next));
+        }
+
+        XRPL_ASSERT(page, "xrpl::detail::internalDirNext : non-null root");
+
+        if (!page)
+            return false;
+
+        index = 0;
+
+        return internalDirNext(view, root, page, index, entry);
+    }
+
+    entry = svIndexes[index++];
+    return true;
+}
+
+template <
+    class V,
+    class N,
+    class = std::enable_if_t<
+        std::is_same_v<std::remove_cv_t<N>, SLE> && std::is_base_of_v<ReadView, V>>>
+bool
+internalDirFirst(
+    V& view,
+    uint256 const& root,
+    std::shared_ptr<N>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    if constexpr (std::is_const_v<N>)
+    {
+        page = view.read(keylet::page(root));
+    }
+    else
+    {
+        page = view.peek(keylet::page(root));
+    }
+
+    if (!page)
+        return false;
+
+    index = 0;
+
+    return internalDirNext(view, root, page, index, entry);
+}
+
+}  // namespace detail
+
+/** @{ */
+/** Returns the first entry in the directory, advancing the index
+
+    @deprecated These are legacy function that are considered deprecated
+                and will soon be replaced with an iterator-based model
+                that is easier to use. You should not use them in new code.
+
+    @param view The view against which to operate
+    @param root The root (i.e. first page) of the directory to iterate
+    @param page The current page
+    @param index The index inside the current page
+    @param entry The entry at the current index
+
+    @return true if the directory isn't empty; false otherwise
+ */
+bool
+cdirFirst(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry);
+
+bool
+dirFirst(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry);
+/** @} */
+
+/** @{ */
+/** Returns the next entry in the directory, advancing the index
+
+    @deprecated These are legacy function that are considered deprecated
+                and will soon be replaced with an iterator-based model
+                that is easier to use. You should not use them in new code.
+
+    @param view The view against which to operate
+    @param root The root (i.e. first page) of the directory to iterate
+    @param page The current page
+    @param index The index inside the current page
+    @param entry The entry at the current index
+
+    @return true if the directory isn't empty; false otherwise
+ */
+bool
+cdirNext(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry);
+
+bool
+dirNext(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry);
+/** @} */
+
+/** Iterate all items in the given directory. */
+void
+forEachItem(
+    ReadView const& view,
+    Keylet const& root,
+    std::function<void(std::shared_ptr<SLE const> const&)> const& f);
+
+/** Iterate all items after an item in the given directory.
+    @param after The key of the item to start after
+    @param hint The directory page containing `after`
+    @param limit The maximum number of items to return
+    @return `false` if the iteration failed
+*/
+bool
+forEachItemAfter(
+    ReadView const& view,
+    Keylet const& root,
+    uint256 const& after,
+    std::uint64_t const hint,
+    unsigned int limit,
+    std::function<bool(std::shared_ptr<SLE const> const&)> const& f);
+
+/** Iterate all items in an account's owner directory. */
+inline void
+forEachItem(
+    ReadView const& view,
+    AccountID const& id,
+    std::function<void(std::shared_ptr<SLE const> const&)> const& f)
+{
+    return forEachItem(view, keylet::ownerDir(id), f);
+}
+
+/** Iterate all items after an item in an owner directory.
+    @param after The key of the item to start after
+    @param hint The directory page containing `after`
+    @param limit The maximum number of items to return
+    @return `false` if the iteration failed
+*/
+inline bool
+forEachItemAfter(
+    ReadView const& view,
+    AccountID const& id,
+    uint256 const& after,
+    std::uint64_t const hint,
+    unsigned int limit,
+    std::function<bool(std::shared_ptr<SLE const> const&)> const& f)
+{
+    return forEachItemAfter(view, keylet::ownerDir(id), after, hint, limit, f);
+}
+
+/** Returns `true` if the directory is empty
+    @param key The key of the directory
+*/
+[[nodiscard]] bool
+dirIsEmpty(ReadView const& view, Keylet const& k);
+
+/** Returns a function that sets the owner on a directory SLE */
+[[nodiscard]] std::function<void(SLE::ref)>
+describeOwnerDir(AccountID const& account);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/MPTokenHelpers.h

@@ -0,0 +1,160 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
+#include <xrpl/protocol/MPTIssue.h>
+#include <xrpl/protocol/Rate.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/TER.h>
+
+#include <initializer_list>
+#include <optional>
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] bool
+isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue);
+
+[[nodiscard]] bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
+
+[[nodiscard]] bool
+isFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue, int depth = 0);
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    MPTIssue const& mptIssue,
+    int depth = 0);
+
+//------------------------------------------------------------------------------
+//
+// Transfer rate (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+/** Returns MPT transfer fee as Rate. Rate specifies
+ * the fee as fractions of 1 billion. For example, 1% transfer rate
+ * is represented as 1,010,000,000.
+ * @param issuanceID MPTokenIssuanceID of MPTTokenIssuance object
+ */
+[[nodiscard]] Rate
+transferRate(ReadView const& view, MPTID const& issuanceID);
+
+//------------------------------------------------------------------------------
+//
+// Holding checks (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+canAddHolding(ReadView const& view, MPTIssue const& mptIssue);
+
+//------------------------------------------------------------------------------
+//
+// Authorization (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+authorizeMPToken(
+    ApplyView& view,
+    XRPAmount const& priorBalance,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    beast::Journal journal,
+    std::uint32_t flags = 0,
+    std::optional<AccountID> holderID = std::nullopt);
+
+/** Check if the account lacks required authorization for MPT.
+ *
+ * requireAuth check is recursive for MPT shares in a vault, descending to
+ * assets in the vault, up to maxAssetCheckDepth recursion depth. This is
+ * purely defensive, as we currently do not allow such vaults to be created.
+ */
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& account,
+    AuthType authType = AuthType::Legacy,
+    int depth = 0);
+
+/** Enforce account has MPToken to match its authorization.
+ *
+ *   Called from doApply - it will check for expired (and delete if found any)
+ *   credentials matching DomainID set in MPTokenIssuance. Must be called if
+ *   requireAuth(...MPTIssue...) returned tesSUCCESS or tecEXPIRED in preclaim.
+ */
+[[nodiscard]] TER
+enforceMPTokenAuthorization(
+    ApplyView& view,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    XRPAmount const& priorBalance,
+    beast::Journal j);
+
+/** Check if the destination account is allowed
+ *  to receive MPT. Return tecNO_AUTH if it doesn't
+ *  and tesSUCCESS otherwise.
+ */
+[[nodiscard]] TER
+canTransfer(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& from,
+    AccountID const& to);
+
+//------------------------------------------------------------------------------
+//
+// Empty holding operations (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    MPTIssue const& mptIssue,
+    beast::Journal journal);
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    MPTIssue const& mptIssue,
+    beast::Journal journal);
+
+//------------------------------------------------------------------------------
+//
+// Escrow operations (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+TER
+rippleLockEscrowMPT(
+    ApplyView& view,
+    AccountID const& uGrantorID,
+    STAmount const& saAmount,
+    beast::Journal j);
+
+TER
+rippleUnlockEscrowMPT(
+    ApplyView& view,
+    AccountID const& uGrantorID,
+    AccountID const& uGranteeID,
+    STAmount const& netAmount,
+    STAmount const& grossAmount,
+    beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/OfferHelpers.h

@@ -0,0 +1,28 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+#include <memory>
+
+namespace xrpl {
+
+/** Delete an offer.
+
+    Requirements:
+        The offer must exist.
+        The caller must have already checked permissions.
+
+    @param view The ApplyView to modify.
+    @param sle The offer to delete.
+    @param j Journal for logging.
+
+    @return tesSUCCESS on success, otherwise an error code.
+*/
+// [[nodiscard]] // nodiscard commented out so Flow, BookTip and others compile.
+TER
+offerDelete(ApplyView& view, std::shared_ptr<SLE> const& sle, beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/RippleStateHelpers.h

@@ -0,0 +1,255 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
+#include <xrpl/protocol/IOUAmount.h>
+#include <xrpl/protocol/Issue.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+//------------------------------------------------------------------------------
+//
+// RippleState (Trustline) helpers
+//
+//------------------------------------------------------------------------------
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Credit functions (from Credit.h)
+//
+//------------------------------------------------------------------------------
+
+/** Calculate the maximum amount of IOUs that an account can hold
+    @param view the ledger to check against.
+    @param account the account of interest.
+    @param issuer the issuer of the IOU.
+    @param currency the IOU to check.
+    @return The maximum amount that can be held.
+*/
+/** @{ */
+STAmount
+creditLimit(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency);
+
+IOUAmount
+creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur);
+/** @} */
+
+/** Returns the amount of IOUs issued by issuer that are held by an account
+    @param view the ledger to check against.
+    @param account the account of interest.
+    @param issuer the issuer of the IOU.
+    @param currency the IOU to check.
+*/
+/** @{ */
+STAmount
+creditBalance(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency);
+/** @} */
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] bool
+isIndividualFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer);
+
+[[nodiscard]] inline bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
+{
+    return isIndividualFrozen(view, account, issue.currency, issue.account);
+}
+
+[[nodiscard]] bool
+isFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer);
+
+[[nodiscard]] inline bool
+isFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
+{
+    return isFrozen(view, account, issue.currency, issue.account);
+}
+
+// Overload with depth parameter for uniformity with MPTIssue version.
+// The depth parameter is ignored for IOUs since they don't have vault recursion.
+[[nodiscard]] inline bool
+isFrozen(ReadView const& view, AccountID const& account, Issue const& issue, int /*depth*/)
+{
+    return isFrozen(view, account, issue);
+}
+
+[[nodiscard]] bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer);
+
+[[nodiscard]] inline bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Issue const& issue,
+    int = 0 /*ignored*/)
+{
+    return isDeepFrozen(view, account, issue.currency, issue.account);
+}
+
+[[nodiscard]] inline TER
+checkDeepFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
+{
+    return isDeepFrozen(view, account, issue) ? (TER)tecFROZEN : (TER)tesSUCCESS;
+}
+
+//------------------------------------------------------------------------------
+//
+// Trust line operations
+//
+//------------------------------------------------------------------------------
+
+/** Create a trust line
+
+    This can set an initial balance.
+*/
+[[nodiscard]] TER
+trustCreate(
+    ApplyView& view,
+    bool const bSrcHigh,
+    AccountID const& uSrcAccountID,
+    AccountID const& uDstAccountID,
+    uint256 const& uIndex,      // --> ripple state entry
+    SLE::ref sleAccount,        // --> the account being set.
+    bool const bAuth,           // --> authorize account.
+    bool const bNoRipple,       // --> others cannot ripple through
+    bool const bFreeze,         // --> funds cannot leave
+    bool bDeepFreeze,           // --> can neither receive nor send funds
+    STAmount const& saBalance,  // --> balance of account being set.
+                                // Issuer should be noAccount()
+    STAmount const& saLimit,    // --> limit for account being set.
+                                // Issuer should be the account being set.
+    std::uint32_t uQualityIn,
+    std::uint32_t uQualityOut,
+    beast::Journal j);
+
+[[nodiscard]] TER
+trustDelete(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sleRippleState,
+    AccountID const& uLowAccountID,
+    AccountID const& uHighAccountID,
+    beast::Journal j);
+
+//------------------------------------------------------------------------------
+//
+// IOU issuance/redemption
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+issueIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j);
+
+[[nodiscard]] TER
+redeemIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j);
+
+//------------------------------------------------------------------------------
+//
+// Authorization and transfer checks (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+/** Check if the account lacks required authorization.
+ *
+ * Return tecNO_AUTH or tecNO_LINE if it does
+ * and tesSUCCESS otherwise.
+ *
+ * If StrongAuth then return tecNO_LINE if the RippleState doesn't exist. Return
+ * tecNO_AUTH if lsfRequireAuth is set on the issuer's AccountRoot, and the
+ * RippleState does exist, and the RippleState is not authorized.
+ *
+ * If WeakAuth then return tecNO_AUTH if lsfRequireAuth is set, and the
+ * RippleState exists, and is not authorized. Return tecNO_LINE if
+ * lsfRequireAuth is set and the RippleState doesn't exist. Consequently, if
+ * WeakAuth and lsfRequireAuth is *not* set, this function will return
+ * tesSUCCESS even if RippleState does *not* exist.
+ *
+ * The default "Legacy" auth type is equivalent to WeakAuth.
+ */
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    Issue const& issue,
+    AccountID const& account,
+    AuthType authType = AuthType::Legacy);
+
+/** Check if the destination account is allowed
+ *  to receive IOU. Return terNO_RIPPLE if rippling is
+ *  disabled on both sides and tesSUCCESS otherwise.
+ */
+[[nodiscard]] TER
+canTransfer(ReadView const& view, Issue const& issue, AccountID const& from, AccountID const& to);
+
+//------------------------------------------------------------------------------
+//
+// Empty holding operations (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+/// Any transactors that call addEmptyHolding() in doApply must call
+/// canAddHolding() in preflight with the same View and Asset
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    Issue const& issue,
+    beast::Journal journal);
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    Issue const& issue,
+    beast::Journal journal);
+
+/** Delete trustline to AMM. The passed `sle` must be obtained from a prior
+ * call to view.peek(). Fail if neither side of the trustline is AMM or
+ * if ammAccountID is seated and is not one of the trustline's side.
+ */
+[[nodiscard]] TER
+deleteAMMTrustLine(
+    ApplyView& view,
+    std::shared_ptr<SLE> sleState,
+    std::optional<AccountID> const& ammAccountID,
+    beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/TokenHelpers.h

@@ -0,0 +1,286 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/Asset.h>
+#include <xrpl/protocol/MPTIssue.h>
+#include <xrpl/protocol/Rate.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/TER.h>
+
+#include <initializer_list>
+#include <vector>
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Enums for token handling
+//
+//------------------------------------------------------------------------------
+
+/** Controls the treatment of frozen account balances */
+enum FreezeHandling { fhIGNORE_FREEZE, fhZERO_IF_FROZEN };
+
+/** Controls the treatment of unauthorized MPT balances */
+enum AuthHandling { ahIGNORE_AUTH, ahZERO_IF_UNAUTHORIZED };
+
+/** Controls whether to include the account's full spendable balance */
+enum SpendableHandling { shSIMPLE_BALANCE, shFULL_BALANCE };
+
+enum class WaiveTransferFee : bool { No = false, Yes };
+
+/* Check if MPToken (for MPT) or trust line (for IOU) exists:
+ * - StrongAuth - before checking if authorization is required
+ * - WeakAuth
+ *    for MPT - after checking lsfMPTRequireAuth flag
+ *    for IOU - do not check if trust line exists
+ * - Legacy
+ *    for MPT - before checking lsfMPTRequireAuth flag i.e. same as StrongAuth
+ *    for IOU - do not check if trust line exists i.e. same as WeakAuth
+ */
+enum class AuthType { StrongAuth, WeakAuth, Legacy };
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] bool
+isGlobalFrozen(ReadView const& view, Asset const& asset);
+
+[[nodiscard]] bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, Asset const& asset);
+
+/**
+ *   isFrozen check is recursive for MPT shares in a vault, descending to
+ *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
+ *   purely defensive, as we currently do not allow such vaults to be created.
+ */
+[[nodiscard]] bool
+isFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0);
+
+[[nodiscard]] TER
+checkFrozen(ReadView const& view, AccountID const& account, Issue const& issue);
+
+[[nodiscard]] TER
+checkFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
+
+[[nodiscard]] TER
+checkFrozen(ReadView const& view, AccountID const& account, Asset const& asset);
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    Issue const& issue);
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    Asset const& asset,
+    int depth = 0);
+
+[[nodiscard]] bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    MPTIssue const& mptIssue,
+    int depth = 0);
+
+/**
+ *   isFrozen check is recursive for MPT shares in a vault, descending to
+ *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
+ *   purely defensive, as we currently do not allow such vaults to be created.
+ */
+[[nodiscard]] bool
+isDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0);
+
+[[nodiscard]] TER
+checkDeepFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
+
+[[nodiscard]] TER
+checkDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset);
+
+//------------------------------------------------------------------------------
+//
+// Account balance functions (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+// Returns the amount an account can spend.
+//
+// If shSIMPLE_BALANCE is specified, this is the amount the account can spend
+// without going into debt.
+//
+// If shFULL_BALANCE is specified, this is the amount the account can spend
+// total. Specifically:
+// * The account can go into debt if using a trust line, and the other side has
+// a non-zero limit.
+// * If the account is the asset issuer the limit is defined by the asset /
+//   issuance.
+//
+// <-- saAmount: amount of currency held by account. May be negative.
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer,
+    FreezeHandling zeroIfFrozen,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    Issue const& issue,
+    FreezeHandling zeroIfFrozen,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    MPTIssue const& mptIssue,
+    FreezeHandling zeroIfFrozen,
+    AuthHandling zeroIfUnauthorized,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    Asset const& asset,
+    FreezeHandling zeroIfFrozen,
+    AuthHandling zeroIfUnauthorized,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+// Returns the amount an account can spend of the currency type saDefault, or
+// returns saDefault if this account is the issuer of the currency in
+// question. Should be used in favor of accountHolds when questioning how much
+// an account can spend while also allowing currency issuers to spend
+// unlimited amounts of their own currency (since they can always issue more).
+[[nodiscard]] STAmount
+accountFunds(
+    ReadView const& view,
+    AccountID const& id,
+    STAmount const& saDefault,
+    FreezeHandling freezeHandling,
+    beast::Journal j);
+
+/** Returns the transfer fee as Rate based on the type of token
+ * @param view The ledger view
+ * @param amount The amount to transfer
+ */
+[[nodiscard]] Rate
+transferRate(ReadView const& view, STAmount const& amount);
+
+//------------------------------------------------------------------------------
+//
+// Holding operations (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+canAddHolding(ReadView const& view, Asset const& asset);
+
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    Asset const& asset,
+    beast::Journal journal);
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    Asset const& asset,
+    beast::Journal journal);
+
+//------------------------------------------------------------------------------
+//
+// Authorization and transfer checks (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    Asset const& asset,
+    AccountID const& account,
+    AuthType authType = AuthType::Legacy);
+
+[[nodiscard]] TER
+canTransfer(ReadView const& view, Asset const& asset, AccountID const& from, AccountID const& to);
+
+//------------------------------------------------------------------------------
+//
+// Money Transfers (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+// Direct send w/o fees:
+// - Redeeming IOUs and/or sending sender's own IOUs.
+// - Create trust line of needed.
+// --> bCheckIssuer : normally require issuer to be involved.
+// [[nodiscard]] // nodiscard commented out so DirectStep.cpp compiles.
+
+/** Calls static rippleCreditIOU if saAmount represents Issue.
+ * Calls static rippleCreditMPT if saAmount represents MPTIssue.
+ */
+TER
+rippleCredit(
+    ApplyView& view,
+    AccountID const& uSenderID,
+    AccountID const& uReceiverID,
+    STAmount const& saAmount,
+    bool bCheckIssuer,
+    beast::Journal j);
+
+/** Calls static accountSendIOU if saAmount represents Issue.
+ * Calls static accountSendMPT if saAmount represents MPTIssue.
+ */
+[[nodiscard]] TER
+accountSend(
+    ApplyView& view,
+    AccountID const& from,
+    AccountID const& to,
+    STAmount const& saAmount,
+    beast::Journal j,
+    WaiveTransferFee waiveFee = WaiveTransferFee::No);
+
+using MultiplePaymentDestinations = std::vector<std::pair<AccountID, Number>>;
+/** Like accountSend, except one account is sending multiple payments (with the
+ *  same asset!) simultaneously
+ *
+ * Calls static accountSendMultiIOU if saAmount represents Issue.
+ * Calls static accountSendMultiMPT if saAmount represents MPTIssue.
+ */
+[[nodiscard]] TER
+accountSendMulti(
+    ApplyView& view,
+    AccountID const& senderID,
+    Asset const& asset,
+    MultiplePaymentDestinations const& receivers,
+    beast::Journal j,
+    WaiveTransferFee waiveFee = WaiveTransferFee::No);
+
+[[nodiscard]] TER
+transferXRP(
+    ApplyView& view,
+    AccountID const& from,
+    AccountID const& to,
+    STAmount const& amount,
+    beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/VaultHelpers.h

@@ -0,0 +1,81 @@
+#pragma once
+
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+
+#include <memory>
+#include <optional>
+
+namespace xrpl {
+
+/** From the perspective of a vault, return the number of shares to give
+    depositor when they offer a fixed amount of assets. Note, since shares are
+    MPT, this number is integral and always truncated in this calculation.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param assets The amount of assets to convert.
+
+    @return The number of shares, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets);
+
+/** From the perspective of a vault, return the number of assets to take from
+    depositor when they receive a fixed amount of shares. Note, since shares are
+    MPT, they are always an integral number.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param shares The amount of shares to convert.
+
+    @return The number of assets, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares);
+
+/** Controls whether to truncate shares instead of rounding. */
+enum class TruncateShares : bool { no = false, yes = true };
+
+/** From the perspective of a vault, return the number of shares to demand from
+    the depositor when they ask to withdraw a fixed amount of assets. Since
+    shares are MPT this number is integral, and it will be rounded to nearest
+    unless explicitly requested to be truncated instead.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param assets The amount of assets to convert.
+    @param truncate Whether to truncate instead of rounding.
+
+    @return The number of shares, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets,
+    TruncateShares truncate = TruncateShares::no);
+
+/** From the perspective of a vault, return the number of assets to give the
+    depositor when they redeem a fixed amount of shares. Note, since shares are
+    MPT, they are always an integral number.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param shares The amount of shares to convert.
+
+    @return The number of assets, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares);
+
+}  // namespace xrpl

include/xrpl/protocol/Fees.h

@@ -4,6 +4,8 @@
 
 namespace xrpl {
 
+constexpr std::uint32_t MICRO_DROPS_PER_DROP{1'000'000};
+
 /** Reflects the fee settings for a particular ledger.
 
     The fees are always the same for any transactions applied
@@ -11,9 +13,12 @@ namespace xrpl {
 */
 struct Fees
 {
-    XRPAmount base{0};       // Reference tx cost (drops)
-    XRPAmount reserve{0};    // Reserve base (drops)
-    XRPAmount increment{0};  // Reserve increment (drops)
+    XRPAmount base{0};                       // Reference tx cost (drops)
+    XRPAmount reserve{0};                    // Reserve base (drops)
+    XRPAmount increment{0};                  // Reserve increment (drops)
+    std::uint32_t extensionComputeLimit{0};  // Extension compute limit (instructions)
+    std::uint32_t extensionSizeLimit{0};     // Extension size limit (bytes)
+    std::uint32_t gasPrice{0};               // price of WASM gas (micro-drops)
 
     explicit Fees() = default;
     Fees(Fees const&) = default;

include/xrpl/protocol/Indexes.h

@@ -207,6 +207,12 @@ page(Keylet const& root, std::uint64_t index = 0) noexcept
 Keylet
 escrow(AccountID const& src, std::uint32_t seq) noexcept;
 
+inline Keylet
+escrow(uint256 const& key) noexcept
+{
+    return {ltESCROW, key};
+}
+
 /** A PaymentChannel */
 Keylet
 payChan(AccountID const& src, AccountID const& dst, std::uint32_t seq) noexcept;

include/xrpl/protocol/Protocol.h

@@ -251,6 +251,12 @@ std::uint8_t constexpr vaultMaximumIOUScale = 18;
  * another vault; counted from 0 */
 std::uint8_t constexpr maxAssetCheckDepth = 5;
 
+/** Maximum length of a Data field in Escrow object that can be updated by WASM code. */
+std::size_t constexpr maxWasmDataLength = 4 * 1024;  // 4KB
+
+/** Maximum length of parameters passed from WASM code to host functions. */
+std::size_t constexpr maxWasmParamLength = 1024;  // 1KB
+
 /** A ledger index. */
 using LedgerIndex = std::uint32_t;
 

include/xrpl/protocol/TER.h

@@ -121,6 +121,9 @@ enum TEMcodes : TERUnderlyingType {
     temARRAY_TOO_LARGE,
     temBAD_TRANSFER_FEE,
     temINVALID_INNER_BATCH,
+
+    temBAD_WASM,
+    temTEMP_DISABLED,
 };
 
 //------------------------------------------------------------------------------
@@ -165,6 +168,8 @@ enum TEFcodes : TERUnderlyingType {
     tefNO_TICKET,
     tefNFTOKEN_IS_NOT_TRANSFERABLE,
     tefINVALID_LEDGER_FIX_TYPE,
+    tefNO_WASM,
+    tefWASM_FIELD_NOT_INCLUDED,
 };
 
 //------------------------------------------------------------------------------
@@ -346,6 +351,7 @@ enum TECcodes : TERUnderlyingType {
     // backward compatibility with historical data on non-prod networks, can be
     // reclaimed after those networks reset.
     tecNO_DELEGATE_PERMISSION = 198,
+    tecWASM_REJECTED = 199,
 };
 
 //------------------------------------------------------------------------------

include/xrpl/protocol/TxMeta.h

@@ -84,6 +84,12 @@ public:
 
         if (obj.isFieldPresent(sfParentBatchID))
             parentBatchID_ = obj.getFieldH256(sfParentBatchID);
+
+        if (obj.isFieldPresent(sfGasUsed))
+            gasUsed_ = obj.getFieldU32(sfGasUsed);
+
+        if (obj.isFieldPresent(sfWasmReturnCode))
+            wasmReturnCode_ = obj.getFieldI32(sfWasmReturnCode);
     }
 
     std::optional<STAmount> const&
@@ -104,6 +110,30 @@ public:
         parentBatchID_ = id;
     }
 
+    void
+    setGasUsed(std::optional<std::uint32_t> const gasUsed)
+    {
+        gasUsed_ = gasUsed;
+    }
+
+    std::optional<std::uint32_t> const&
+    getGasUsed() const
+    {
+        return gasUsed_;
+    }
+
+    void
+    setWasmReturnCode(std::optional<std::int32_t> const wasmReturnCode)
+    {
+        wasmReturnCode_ = wasmReturnCode;
+    }
+
+    std::optional<std::int32_t> const&
+    getWasmReturnCode() const
+    {
+        return wasmReturnCode_;
+    }
+
 private:
     uint256 transactionID_;
     std::uint32_t ledgerSeq_;
@@ -112,6 +142,8 @@ private:
 
     std::optional<STAmount> deliveredAmount_;
     std::optional<uint256> parentBatchID_;
+    std::optional<std::uint32_t> gasUsed_;
+    std::optional<std::int32_t> wasmReturnCode_;
 
     STArray nodes_;
 };

include/xrpl/protocol/detail/features.macro

@@ -16,7 +16,8 @@
 // Add new amendments to the top of this list.
 // Keep it sorted in reverse chronological order.
 
-XRPL_FIX   (PermissionedDomainInvariant, Supported::yes, VoteBehavior::DefaultNo)
+XRPL_FEATURE(SmartEscrow,                Supported::yes, VoteBehavior::DefaultNo)
+XRPL_FIX    (PermissionedDomainInvariant, Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (ExpiredNFTokenOfferRemoval, Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (BatchInnerSigs,             Supported::no, VoteBehavior::DefaultNo)
 XRPL_FEATURE(LendingProtocol,            Supported::yes, VoteBehavior::DefaultNo)
@@ -33,9 +34,8 @@ XRPL_FIX    (EnforceNFTokenTrustlineV2,  Supported::yes, VoteBehavior::DefaultNo
 XRPL_FIX    (AMMv1_3,                    Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FEATURE(PermissionedDEX,            Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FEATURE(Batch,                      Supported::no,  VoteBehavior::DefaultNo)
-XRPL_FEATURE(SingleAssetVault,           Supported::yes,  VoteBehavior::DefaultNo)
+XRPL_FEATURE(SingleAssetVault,           Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (PayChanCancelAfter,         Supported::yes, VoteBehavior::DefaultNo)
-// Check flags in Credential transactions
 XRPL_FIX    (InvalidTxFlags,             Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (FrozenLPTokenTransfer,      Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FEATURE(DeepFreeze,                 Supported::yes, VoteBehavior::DefaultNo)

include/xrpl/protocol/detail/ledger_entries.macro

@@ -302,6 +302,11 @@ LEDGER_ENTRY(ltFEE_SETTINGS, 0x0073, FeeSettings, fee, ({
     {sfBaseFeeDrops,           soeOPTIONAL},
     {sfReserveBaseDrops,       soeOPTIONAL},
     {sfReserveIncrementDrops,  soeOPTIONAL},
+    // Smart Escrow fields
+    {sfExtensionComputeLimit,  soeOPTIONAL},
+    {sfExtensionSizeLimit,     soeOPTIONAL},
+    {sfGasPrice,               soeOPTIONAL},
+
     {sfPreviousTxnID,          soeOPTIONAL},
     {sfPreviousTxnLgrSeq,      soeOPTIONAL},
 }))
@@ -332,6 +337,8 @@ LEDGER_ENTRY(ltESCROW, 0x0075, Escrow, escrow, ({
     {sfCondition,            soeOPTIONAL},
     {sfCancelAfter,          soeOPTIONAL},
     {sfFinishAfter,          soeOPTIONAL},
+    {sfFinishFunction,       soeOPTIONAL},
+    {sfData,                 soeOPTIONAL},
     {sfSourceTag,            soeOPTIONAL},
     {sfDestinationTag,       soeOPTIONAL},
     {sfOwnerNode,            soeREQUIRED},
@@ -578,7 +585,7 @@ LEDGER_ENTRY(ltLOAN, 0x0089, Loan, loan, ({
     //   The unrounded true total value of the loan.
     //
     // - TrueTotalPrincipalOutstanding can be computed using the algorithm
-    //   in the ripple::detail::loanPrincipalFromPeriodicPayment function.
+    //   in the xrpl::detail::loanPrincipalFromPeriodicPayment function.
     //
     // - TrueTotalInterestOutstanding = TrueTotalLoanValue -
     //      TrueTotalPrincipalOutstanding

include/xrpl/protocol/detail/sfields.macro

@@ -114,6 +114,11 @@ TYPED_SFIELD(sfInterestRate,             UINT32,    65) // 1/10 basis points (bi
 TYPED_SFIELD(sfLateInterestRate,         UINT32,    66) // 1/10 basis points (bips)
 TYPED_SFIELD(sfCloseInterestRate,        UINT32,    67) // 1/10 basis points (bips)
 TYPED_SFIELD(sfOverpaymentInterestRate,  UINT32,    68) // 1/10 basis points (bips)
+TYPED_SFIELD(sfExtensionComputeLimit,    UINT32,    69)
+TYPED_SFIELD(sfExtensionSizeLimit,       UINT32,    70)
+TYPED_SFIELD(sfGasPrice,                 UINT32,    71)
+TYPED_SFIELD(sfComputationAllowance,     UINT32,    72)
+TYPED_SFIELD(sfGasUsed,                  UINT32,    73)
 
 // 64-bit integers (common)
 TYPED_SFIELD(sfIndexNext,                UINT64,     1)
@@ -224,8 +229,9 @@ TYPED_SFIELD(sfTotalValueOutstanding,    NUMBER,     15, SField::sMD_NeedsAsset
 TYPED_SFIELD(sfPeriodicPayment,          NUMBER,     16)
 TYPED_SFIELD(sfManagementFeeOutstanding, NUMBER,     17, SField::sMD_NeedsAsset | SField::sMD_Default)
 
-// int32
+// 32-bit signed (common)
 TYPED_SFIELD(sfLoanScale,                INT32,      1)
+TYPED_SFIELD(sfWasmReturnCode,           INT32,      2)
 
 // currency amount (common)
 TYPED_SFIELD(sfAmount,                   AMOUNT,     1)
@@ -255,7 +261,7 @@ TYPED_SFIELD(sfBaseFeeDrops,             AMOUNT,    22)
 TYPED_SFIELD(sfReserveBaseDrops,         AMOUNT,    23)
 TYPED_SFIELD(sfReserveIncrementDrops,    AMOUNT,    24)
 
-// currency amount (AMM)
+// currency amount (more)
 TYPED_SFIELD(sfLPTokenOut,               AMOUNT,    25)
 TYPED_SFIELD(sfLPTokenIn,                AMOUNT,    26)
 TYPED_SFIELD(sfEPrice,                   AMOUNT,    27)
@@ -297,6 +303,7 @@ TYPED_SFIELD(sfAssetClass,               VL,        28)
 TYPED_SFIELD(sfProvider,                 VL,        29)
 TYPED_SFIELD(sfMPTokenMetadata,          VL,        30)
 TYPED_SFIELD(sfCredentialType,           VL,        31)
+TYPED_SFIELD(sfFinishFunction,           VL,        32)
 
 // account (common)
 TYPED_SFIELD(sfAccount,                  ACCOUNT,    1)

include/xrpl/protocol/detail/transactions.macro

@@ -50,11 +50,13 @@ TRANSACTION(ttESCROW_CREATE, 1, EscrowCreate,
     noPriv,
     ({
     {sfDestination, soeREQUIRED},
+    {sfDestinationTag, soeOPTIONAL},
     {sfAmount, soeREQUIRED, soeMPTSupported},
     {sfCondition, soeOPTIONAL},
     {sfCancelAfter, soeOPTIONAL},
     {sfFinishAfter, soeOPTIONAL},
-    {sfDestinationTag, soeOPTIONAL},
+    {sfFinishFunction, soeOPTIONAL},
+    {sfData,           soeOPTIONAL},
 }))
 
 /** This transaction type completes an existing escrow. */
@@ -71,6 +73,7 @@ TRANSACTION(ttESCROW_FINISH, 2, EscrowFinish,
     {sfFulfillment, soeOPTIONAL},
     {sfCondition, soeOPTIONAL},
     {sfCredentialIDs, soeOPTIONAL},
+    {sfComputationAllowance, soeOPTIONAL},
 }))
 
 
@@ -1110,6 +1113,10 @@ TRANSACTION(ttFEE, 101, SetFee,
     {sfBaseFeeDrops, soeOPTIONAL},
     {sfReserveBaseDrops, soeOPTIONAL},
     {sfReserveIncrementDrops, soeOPTIONAL},
+    // Smart Escrow fields
+    {sfExtensionComputeLimit, soeOPTIONAL},
+    {sfExtensionSizeLimit, soeOPTIONAL},
+    {sfGasPrice, soeOPTIONAL},
 }))
 
 /** This system-generated transaction type is used to update the network's negative UNL

include/xrpl/protocol/jss.h

@@ -257,6 +257,9 @@ JSS(expected_date_UTC);       // out: any (warnings)
 JSS(expected_ledger_size);    // out: TxQ
 JSS(expiration);              // out: AccountOffers, AccountChannels,
                               //      ValidatorList, amm_info
+JSS(extension_compute);       // out: NetworkOps
+JSS(extension_size);          // out: NetworkOps
+JSS(gas_price);               // out: NetworkOps
 JSS(fail_hard);               // in: Sign, Submit
 JSS(failed);                  // out: InboundLedger
 JSS(feature);                 // in: Feature
@@ -718,11 +721,11 @@ JSS(write_load);              // out: GetCounts
 #pragma push_macro("LEDGER_ENTRY_DUPLICATE")
 #undef LEDGER_ENTRY_DUPLICATE
 
-#define LEDGER_ENTRY(tag, value, name, rpcName, ...) \
-    JSS(name);                                       \
+#define LEDGER_ENTRY(tag, value, name, rpcName, fields) \
+    JSS(name);                                          \
     JSS(rpcName);
 
-#define LEDGER_ENTRY_DUPLICATE(tag, value, name, rpcName, ...) JSS(rpcName);
+#define LEDGER_ENTRY_DUPLICATE(tag, value, name, rpcName, fields) JSS(rpcName);
 
 #include <xrpl/protocol/detail/ledger_entries.macro>
 

include/xrpl/tx/ApplyContext.h

@@ -75,6 +75,20 @@ public:
         view_->deliver(amount);
     }
 
+    /** Sets the gas used in the metadata */
+    void
+    setGasUsed(std::uint32_t const gasUsed)
+    {
+        gasUsed_ = gasUsed;
+    }
+
+    /** Sets the gas used in the metadata */
+    void
+    setWasmReturnCode(std::int32_t const wasmReturnCode)
+    {
+        wasmReturnCode_ = wasmReturnCode;
+    }
+
     /** Discard changes and start fresh. */
     void
     discard();
@@ -124,6 +138,8 @@ private:
 
     // The ID of the batch transaction we are executing under, if seated.
     std::optional<uint256 const> parentBatchId_;
+    std::optional<std::uint32_t> gasUsed_;
+    std::optional<std::int32_t> wasmReturnCode_;
 };
 
 }  // namespace xrpl

include/xrpl/tx/paths/detail/StrandFlow.h

@@ -1,7 +1,9 @@
 #pragma once
 
 #include <xrpl/basics/Log.h>
-#include <xrpl/ledger/Credit.h>
+#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/IOUAmount.h>
 #include <xrpl/protocol/XRPAmount.h>

include/xrpl/tx/transactors/dex/AMMUtils.h

@@ -3,6 +3,7 @@
 #include <xrpl/basics/Expected.h>
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/STLedgerEntry.h>
 #include <xrpl/protocol/TER.h>

include/xrpl/tx/transactors/dex/AMMWithdraw.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/tx/Transactor.h>
 
 namespace xrpl {

include/xrpl/tx/transactors/escrow/EscrowCreate.h

@@ -13,12 +13,21 @@ public:
     {
     }
 
+    static bool
+    checkExtraFeatures(PreflightContext const& ctx);
+
     static TxConsequences
     makeTxConsequences(PreflightContext const& ctx);
 
+    static XRPAmount
+    calculateBaseFee(ReadView const& view, STTx const& tx);
+
     static NotTEC
     preflight(PreflightContext const& ctx);
 
+    static NotTEC
+    preflightSigValidated(PreflightContext const& ctx);
+
     static TER
     preclaim(PreclaimContext const& ctx);
 

include/xrpl/tx/wasm/HostFunc.h

@@ -0,0 +1,501 @@
+#pragma once
+
+#include <xrpl/basics/Expected.h>
+#include <xrpl/basics/Slice.h>
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/Asset.h>
+#include <xrpl/protocol/Keylet.h>
+#include <xrpl/protocol/TER.h>
+#include <xrpl/protocol/UintTypes.h>
+#include <xrpl/tx/wasm/ParamsHelper.h>
+
+namespace xrpl {
+
+enum class HostFunctionError : int32_t {
+    INTERNAL = -1,
+    FIELD_NOT_FOUND = -2,
+    BUFFER_TOO_SMALL = -3,
+    NO_ARRAY = -4,
+    NOT_LEAF_FIELD = -5,
+    LOCATOR_MALFORMED = -6,
+    SLOT_OUT_RANGE = -7,
+    SLOTS_FULL = -8,
+    EMPTY_SLOT = -9,
+    LEDGER_OBJ_NOT_FOUND = -10,
+    DECODING = -11,
+    DATA_FIELD_TOO_LARGE = -12,
+    POINTER_OUT_OF_BOUNDS = -13,
+    NO_MEM_EXPORTED = -14,
+    INVALID_PARAMS = -15,
+    INVALID_ACCOUNT = -16,
+    INVALID_FIELD = -17,
+    INDEX_OUT_OF_BOUNDS = -18,
+    FLOAT_INPUT_MALFORMED = -19,
+    FLOAT_COMPUTATION_ERROR = -20,
+    NO_RUNTIME = -21,
+    OUT_OF_GAS = -22,
+};
+
+inline int32_t
+HfErrorToInt(HostFunctionError e)
+{
+    return static_cast<int32_t>(e);
+}
+
+namespace wasm_float {
+
+std::string
+floatToString(Slice const& data);
+
+Expected<Bytes, HostFunctionError>
+floatFromIntImpl(int64_t x, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatFromUintImpl(uint64_t x, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatSetImpl(int64_t mantissa, int32_t exponent, int32_t mode);
+
+Expected<int32_t, HostFunctionError>
+floatCompareImpl(Slice const& x, Slice const& y);
+
+Expected<Bytes, HostFunctionError>
+floatAddImpl(Slice const& x, Slice const& y, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatSubtractImpl(Slice const& x, Slice const& y, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatMultiplyImpl(Slice const& x, Slice const& y, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatDivideImpl(Slice const& x, Slice const& y, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatRootImpl(Slice const& x, int32_t n, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatPowerImpl(Slice const& x, int32_t n, int32_t mode);
+
+Expected<Bytes, HostFunctionError>
+floatLogImpl(Slice const& x, int32_t mode);
+
+}  // namespace wasm_float
+
+struct HostFunctions
+{
+    beast::Journal j_;
+
+    HostFunctions(beast::Journal j = beast::Journal{beast::Journal::getNullSink()}) : j_(j)
+    {
+    }
+
+    // LCOV_EXCL_START
+    virtual void
+    setRT(void const*)
+    {
+    }
+
+    virtual void const*
+    getRT() const
+    {
+        return nullptr;
+    }
+
+    beast::Journal
+    getJournal() const
+    {
+        return j_;
+    }
+
+    virtual bool
+    checkSelf() const
+    {
+        return true;
+    }
+
+    virtual Expected<std::uint32_t, HostFunctionError>
+    getLedgerSqn() const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<std::uint32_t, HostFunctionError>
+    getParentLedgerTime() const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Hash, HostFunctionError>
+    getParentLedgerHash() const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<uint32_t, HostFunctionError>
+    getBaseFee() const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    isAmendmentEnabled(uint256 const& amendmentId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    isAmendmentEnabled(std::string_view const& amendmentName) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    cacheLedgerObj(uint256 const& objId, int32_t cacheIdx)
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getTxField(SField const& fname) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getCurrentLedgerObjField(SField const& fname) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getLedgerObjField(int32_t cacheIdx, SField const& fname) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getTxNestedField(Slice const& locator) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getCurrentLedgerObjNestedField(Slice const& locator) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getLedgerObjNestedField(int32_t cacheIdx, Slice const& locator) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getTxArrayLen(SField const& fname) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getCurrentLedgerObjArrayLen(SField const& fname) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getLedgerObjArrayLen(int32_t cacheIdx, SField const& fname) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getTxNestedArrayLen(Slice const& locator) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getCurrentLedgerObjNestedArrayLen(Slice const& locator) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getLedgerObjNestedArrayLen(int32_t cacheIdx, Slice const& locator) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    updateData(Slice const& data)
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    checkSignature(Slice const& message, Slice const& signature, Slice const& pubkey) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Hash, HostFunctionError>
+    computeSha512HalfHash(Slice const& data) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    accountKeylet(AccountID const& account) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    ammKeylet(Asset const& issue1, Asset const& issue2) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    checkKeylet(AccountID const& account, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    credentialKeylet(AccountID const& subject, AccountID const& issuer, Slice const& credentialType)
+        const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    didKeylet(AccountID const& account) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    delegateKeylet(AccountID const& account, AccountID const& authorize) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    depositPreauthKeylet(AccountID const& account, AccountID const& authorize) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    escrowKeylet(AccountID const& account, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    lineKeylet(AccountID const& account1, AccountID const& account2, Currency const& currency) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    mptIssuanceKeylet(AccountID const& issuer, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    mptokenKeylet(MPTID const& mptid, AccountID const& holder) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    nftOfferKeylet(AccountID const& account, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    offerKeylet(AccountID const& account, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    oracleKeylet(AccountID const& account, std::uint32_t docId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    paychanKeylet(AccountID const& account, AccountID const& destination, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    permissionedDomainKeylet(AccountID const& account, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    signersKeylet(AccountID const& account) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    ticketKeylet(AccountID const& account, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    vaultKeylet(AccountID const& account, std::uint32_t seq) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getNFT(AccountID const& account, uint256 const& nftId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    getNFTIssuer(uint256 const& nftId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<std::uint32_t, HostFunctionError>
+    getNFTTaxon(uint256 const& nftId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getNFTFlags(uint256 const& nftId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    getNFTTransferFee(uint256 const& nftId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<std::uint32_t, HostFunctionError>
+    getNFTSerial(uint256 const& nftId) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    trace(std::string_view const& msg, Slice const& data, bool asHex) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    traceNum(std::string_view const& msg, int64_t data) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    traceAccount(std::string_view const& msg, AccountID const& account) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    traceFloat(std::string_view const& msg, Slice const& data) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    traceAmount(std::string_view const& msg, STAmount const& amount) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatFromInt(int64_t x, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatFromUint(uint64_t x, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatSet(int64_t mantissa, int32_t exponent, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<int32_t, HostFunctionError>
+    floatCompare(Slice const& x, Slice const& y) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatAdd(Slice const& x, Slice const& y, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatSubtract(Slice const& x, Slice const& y, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatMultiply(Slice const& x, Slice const& y, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatDivide(Slice const& x, Slice const& y, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatRoot(Slice const& x, int32_t n, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatPower(Slice const& x, int32_t n, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual Expected<Bytes, HostFunctionError>
+    floatLog(Slice const& x, int32_t mode) const
+    {
+        return Unexpected(HostFunctionError::INTERNAL);
+    }
+
+    virtual ~HostFunctions() = default;
+    // LCOV_EXCL_STOP
+};
+
+}  // namespace xrpl

include/xrpl/tx/wasm/HostFuncImpl.h

@@ -0,0 +1,295 @@
+#pragma once
+
+#include <xrpl/tx/ApplyContext.h>
+#include <xrpl/tx/wasm/HostFunc.h>
+
+namespace xrpl {
+class WasmHostFunctionsImpl : public HostFunctions
+{
+    ApplyContext& ctx_;
+
+    Keylet leKey_;
+    mutable std::optional<std::shared_ptr<SLE const>> currentLedgerObj_;
+
+    static int constexpr MAX_CACHE = 256;
+    std::array<std::shared_ptr<SLE const>, MAX_CACHE> cache_;
+
+    std::optional<Bytes> data_;
+
+    void const* rt_ = nullptr;
+
+    Expected<std::shared_ptr<SLE const>, HostFunctionError>
+    getCurrentLedgerObj() const
+    {
+        if (!currentLedgerObj_)
+            currentLedgerObj_ = ctx_.view().read(leKey_);
+        if (*currentLedgerObj_)
+            return *currentLedgerObj_;
+        return Unexpected(HostFunctionError::LEDGER_OBJ_NOT_FOUND);
+    }
+
+    Expected<int32_t, HostFunctionError>
+    normalizeCacheIndex(int32_t cacheIdx) const
+    {
+        --cacheIdx;
+        if (cacheIdx < 0 || cacheIdx >= MAX_CACHE)
+            return Unexpected(HostFunctionError::SLOT_OUT_RANGE);
+        if (!cache_[cacheIdx])
+            return Unexpected(HostFunctionError::EMPTY_SLOT);
+        return cacheIdx;
+    }
+
+    template <typename F>
+    void
+    log(std::string_view const& msg, F&& dataFn) const
+    {
+#ifdef DEBUG_OUTPUT
+        auto& j = std::cerr;
+#else
+        if (!getJournal().active(beast::severities::kTrace))
+            return;
+        auto j = getJournal().trace();
+#endif
+        j << "WasmTrace[" << to_short_string(leKey_.key) << "]: " << msg << " " << dataFn();
+
+#ifdef DEBUG_OUTPUT
+        j << std::endl;
+#endif
+    }
+
+public:
+    WasmHostFunctionsImpl(ApplyContext& ct, Keylet const& leKey)
+        : HostFunctions(ct.journal), ctx_(ct), leKey_(leKey)
+    {
+    }
+
+    virtual void
+    setRT(void const* rt) override
+    {
+        rt_ = rt;
+    }
+
+    virtual void const*
+    getRT() const override
+    {
+        return rt_;
+    }
+
+    virtual bool
+    checkSelf() const override
+    {
+        return !currentLedgerObj_ && !data_ &&
+            std::ranges::find_if(cache_, [](auto& p) { return !!p; }) == cache_.end();
+    }
+
+    std::optional<Bytes> const&
+    getData() const
+    {
+        return data_;
+    }
+
+    Expected<std::uint32_t, HostFunctionError>
+    getLedgerSqn() const override;
+
+    Expected<std::uint32_t, HostFunctionError>
+    getParentLedgerTime() const override;
+
+    Expected<Hash, HostFunctionError>
+    getParentLedgerHash() const override;
+
+    Expected<std::uint32_t, HostFunctionError>
+    getBaseFee() const override;
+
+    Expected<int32_t, HostFunctionError>
+    isAmendmentEnabled(uint256 const& amendmentId) const override;
+
+    Expected<int32_t, HostFunctionError>
+    isAmendmentEnabled(std::string_view const& amendmentName) const override;
+
+    Expected<int32_t, HostFunctionError>
+    cacheLedgerObj(uint256 const& objId, int32_t cacheIdx) override;
+
+    Expected<Bytes, HostFunctionError>
+    getTxField(SField const& fname) const override;
+
+    Expected<Bytes, HostFunctionError>
+    getCurrentLedgerObjField(SField const& fname) const override;
+
+    Expected<Bytes, HostFunctionError>
+    getLedgerObjField(int32_t cacheIdx, SField const& fname) const override;
+
+    Expected<Bytes, HostFunctionError>
+    getTxNestedField(Slice const& locator) const override;
+
+    Expected<Bytes, HostFunctionError>
+    getCurrentLedgerObjNestedField(Slice const& locator) const override;
+
+    Expected<Bytes, HostFunctionError>
+    getLedgerObjNestedField(int32_t cacheIdx, Slice const& locator) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getTxArrayLen(SField const& fname) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getCurrentLedgerObjArrayLen(SField const& fname) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getLedgerObjArrayLen(int32_t cacheIdx, SField const& fname) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getTxNestedArrayLen(Slice const& locator) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getCurrentLedgerObjNestedArrayLen(Slice const& locator) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getLedgerObjNestedArrayLen(int32_t cacheIdx, Slice const& locator) const override;
+
+    Expected<int32_t, HostFunctionError>
+    updateData(Slice const& data) override;
+
+    Expected<int32_t, HostFunctionError>
+    checkSignature(Slice const& message, Slice const& signature, Slice const& pubkey)
+        const override;
+
+    Expected<Hash, HostFunctionError>
+    computeSha512HalfHash(Slice const& data) const override;
+
+    Expected<Bytes, HostFunctionError>
+    accountKeylet(AccountID const& account) const override;
+
+    Expected<Bytes, HostFunctionError>
+    ammKeylet(Asset const& issue1, Asset const& issue2) const override;
+
+    Expected<Bytes, HostFunctionError>
+    checkKeylet(AccountID const& account, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    credentialKeylet(AccountID const& subject, AccountID const& issuer, Slice const& credentialType)
+        const override;
+
+    Expected<Bytes, HostFunctionError>
+    didKeylet(AccountID const& account) const override;
+
+    Expected<Bytes, HostFunctionError>
+    delegateKeylet(AccountID const& account, AccountID const& authorize) const override;
+
+    Expected<Bytes, HostFunctionError>
+    depositPreauthKeylet(AccountID const& account, AccountID const& authorize) const override;
+
+    Expected<Bytes, HostFunctionError>
+    escrowKeylet(AccountID const& account, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    lineKeylet(AccountID const& account1, AccountID const& account2, Currency const& currency)
+        const override;
+
+    Expected<Bytes, HostFunctionError>
+    mptIssuanceKeylet(AccountID const& issuer, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    mptokenKeylet(MPTID const& mptid, AccountID const& holder) const override;
+
+    Expected<Bytes, HostFunctionError>
+    nftOfferKeylet(AccountID const& account, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    offerKeylet(AccountID const& account, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    oracleKeylet(AccountID const& account, std::uint32_t docId) const override;
+
+    Expected<Bytes, HostFunctionError>
+    paychanKeylet(AccountID const& account, AccountID const& destination, std::uint32_t seq)
+        const override;
+
+    Expected<Bytes, HostFunctionError>
+    permissionedDomainKeylet(AccountID const& account, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    signersKeylet(AccountID const& account) const override;
+
+    Expected<Bytes, HostFunctionError>
+    ticketKeylet(AccountID const& account, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    vaultKeylet(AccountID const& account, std::uint32_t seq) const override;
+
+    Expected<Bytes, HostFunctionError>
+    getNFT(AccountID const& account, uint256 const& nftId) const override;
+
+    Expected<Bytes, HostFunctionError>
+    getNFTIssuer(uint256 const& nftId) const override;
+
+    Expected<std::uint32_t, HostFunctionError>
+    getNFTTaxon(uint256 const& nftId) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getNFTFlags(uint256 const& nftId) const override;
+
+    Expected<int32_t, HostFunctionError>
+    getNFTTransferFee(uint256 const& nftId) const override;
+
+    Expected<std::uint32_t, HostFunctionError>
+    getNFTSerial(uint256 const& nftId) const override;
+
+    Expected<int32_t, HostFunctionError>
+    trace(std::string_view const& msg, Slice const& data, bool asHex) const override;
+
+    Expected<int32_t, HostFunctionError>
+    traceNum(std::string_view const& msg, int64_t data) const override;
+
+    Expected<int32_t, HostFunctionError>
+    traceAccount(std::string_view const& msg, AccountID const& account) const override;
+
+    Expected<int32_t, HostFunctionError>
+    traceFloat(std::string_view const& msg, Slice const& data) const override;
+
+    Expected<int32_t, HostFunctionError>
+    traceAmount(std::string_view const& msg, STAmount const& amount) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatFromInt(int64_t x, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatFromUint(uint64_t x, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatSet(int64_t mantissa, int32_t exponent, int32_t mode) const override;
+
+    Expected<int32_t, HostFunctionError>
+    floatCompare(Slice const& x, Slice const& y) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatAdd(Slice const& x, Slice const& y, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatSubtract(Slice const& x, Slice const& y, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatMultiply(Slice const& x, Slice const& y, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatDivide(Slice const& x, Slice const& y, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatRoot(Slice const& x, int32_t n, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatPower(Slice const& x, int32_t n, int32_t mode) const override;
+
+    Expected<Bytes, HostFunctionError>
+    floatLog(Slice const& x, int32_t mode) const override;
+};
+
+namespace wasm_float {
+
+// The range for the mantissa and exponent when normalized
+static std::int64_t constexpr wasmMinMantissa = 1'000'000'000'000'000ll;
+static std::int64_t constexpr wasmMaxMantissa = wasmMinMantissa * 10 - 1;
+static int constexpr wasmMinExponent = -96;
+static int constexpr wasmMaxExponent = 80;
+
+}  // namespace wasm_float
+
+}  // namespace xrpl

include/xrpl/tx/wasm/HostFuncWrapper.h

@@ -0,0 +1,303 @@
+#pragma once
+
+#include <xrpl/tx/wasm/WasmiVM.h>
+
+namespace xrpl {
+
+using getLedgerSqn_proto = int32_t(uint8_t*, int32_t);
+wasm_trap_t*
+getLedgerSqn_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getParentLedgerTime_proto = int32_t(uint8_t*, int32_t);
+wasm_trap_t*
+getParentLedgerTime_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getParentLedgerHash_proto = int32_t(uint8_t*, int32_t);
+wasm_trap_t*
+getParentLedgerHash_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getBaseFee_proto = int32_t(uint8_t*, int32_t);
+wasm_trap_t*
+getBaseFee_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using isAmendmentEnabled_proto = int32_t(uint8_t const*, int32_t);
+wasm_trap_t*
+isAmendmentEnabled_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using cacheLedgerObj_proto = int32_t(uint8_t const*, int32_t, int32_t);
+wasm_trap_t*
+cacheLedgerObj_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getTxField_proto = int32_t(int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getTxField_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getCurrentLedgerObjField_proto = int32_t(int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getCurrentLedgerObjField_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getLedgerObjField_proto = int32_t(int32_t, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getLedgerObjField_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getTxNestedField_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getTxNestedField_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getCurrentLedgerObjNestedField_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getCurrentLedgerObjNestedField_wrap(
+    void* env,
+    wasm_val_vec_t const* params,
+    wasm_val_vec_t* results);
+
+using getLedgerObjNestedField_proto = int32_t(int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getLedgerObjNestedField_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getTxArrayLen_proto = int32_t(int32_t);
+wasm_trap_t*
+getTxArrayLen_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getCurrentLedgerObjArrayLen_proto = int32_t(int32_t);
+wasm_trap_t*
+getCurrentLedgerObjArrayLen_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getLedgerObjArrayLen_proto = int32_t(int32_t, int32_t);
+wasm_trap_t*
+getLedgerObjArrayLen_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getTxNestedArrayLen_proto = int32_t(uint8_t const*, int32_t);
+wasm_trap_t*
+getTxNestedArrayLen_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getCurrentLedgerObjNestedArrayLen_proto = int32_t(uint8_t const*, int32_t);
+wasm_trap_t*
+getCurrentLedgerObjNestedArrayLen_wrap(
+    void* env,
+    wasm_val_vec_t const* params,
+    wasm_val_vec_t* results);
+
+using getLedgerObjNestedArrayLen_proto = int32_t(int32_t, uint8_t const*, int32_t);
+wasm_trap_t*
+getLedgerObjNestedArrayLen_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using updateData_proto = int32_t(uint8_t const*, int32_t);
+wasm_trap_t*
+updateData_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using checkSignature_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t const*, int32_t);
+wasm_trap_t*
+checkSignature_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using computeSha512HalfHash_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+computeSha512HalfHash_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using accountKeylet_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+accountKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using ammKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+ammKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using checkKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+checkKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using credentialKeylet_proto = int32_t(
+    uint8_t const*,
+    int32_t,
+    uint8_t const*,
+    int32_t,
+    uint8_t const*,
+    int32_t,
+    uint8_t*,
+    int32_t);
+wasm_trap_t*
+credentialKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using delegateKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+delegateKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using depositPreauthKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+depositPreauthKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using didKeylet_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+didKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using escrowKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+escrowKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using lineKeylet_proto = int32_t(
+    uint8_t const*,
+    int32_t,
+    uint8_t const*,
+    int32_t,
+    uint8_t const*,
+    int32_t,
+    uint8_t*,
+    int32_t);
+wasm_trap_t*
+lineKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using mptIssuanceKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+mptIssuanceKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using mptokenKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+mptokenKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using nftOfferKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+nftOfferKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using offerKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+offerKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using oracleKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+oracleKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using paychanKeylet_proto = int32_t(
+    uint8_t const*,
+    int32_t,
+    uint8_t const*,
+    int32_t,
+    uint8_t const*,
+    int32_t,
+    uint8_t*,
+    int32_t);
+wasm_trap_t*
+paychanKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using permissionedDomainKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+permissionedDomainKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using signersKeylet_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+signersKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using ticketKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+ticketKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using vaultKeylet_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+vaultKeylet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getNFT_proto = int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getNFT_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getNFTIssuer_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getNFTIssuer_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getNFTTaxon_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getNFTTaxon_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getNFTFlags_proto = int32_t(uint8_t const*, int32_t);
+wasm_trap_t*
+getNFTFlags_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getNFTTransferFee_proto = int32_t(uint8_t const*, int32_t);
+wasm_trap_t*
+getNFTTransferFee_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using getNFTSerial_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t);
+wasm_trap_t*
+getNFTSerial_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using trace_proto = int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, int32_t);
+wasm_trap_t*
+trace_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using traceNum_proto = int32_t(uint8_t const*, int32_t, int64_t);
+wasm_trap_t*
+traceNum_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using traceAccount_proto = int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t);
+wasm_trap_t*
+traceAccount_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using traceFloat_proto = int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t);
+wasm_trap_t*
+traceFloat_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using traceAmount_proto = int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t);
+wasm_trap_t*
+traceAmount_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatFromInt_proto = int32_t(int64_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatFromInt_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatFromUint_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatFromUint_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatSet_proto = int32_t(int32_t, int64_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatSet_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatCompare_proto = int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t);
+wasm_trap_t*
+floatCompare_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatAdd_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatAdd_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatSubtract_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatSubtract_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatMultiply_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatMultiply_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatDivide_proto =
+    int32_t(uint8_t const*, int32_t, uint8_t const*, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatDivide_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatRoot_proto = int32_t(uint8_t const*, int32_t, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatRoot_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatPower_proto = int32_t(uint8_t const*, int32_t, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatPower_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+using floatLog_proto = int32_t(uint8_t const*, int32_t, uint8_t*, int32_t, int32_t);
+wasm_trap_t*
+floatLog_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+
+}  // namespace xrpl

include/xrpl/tx/wasm/ParamsHelper.h

@@ -0,0 +1,231 @@
+#pragma once
+
+#include <xrpl/basics/base_uint.h>
+
+#include <boost/function_types/function_arity.hpp>
+#include <boost/function_types/parameter_types.hpp>
+#include <boost/function_types/result_type.hpp>
+#include <boost/mpl/vector.hpp>
+
+#include <optional>
+#include <string>
+#include <vector>
+
+namespace bft = boost::function_types;
+
+namespace xrpl {
+
+using Bytes = std::vector<std::uint8_t>;
+using Hash = xrpl::uint256;
+
+struct wmem
+{
+    std::uint8_t* p = nullptr;
+    std::size_t s = 0;
+};
+
+template <typename T>
+struct WasmResult
+{
+    T result;
+    int64_t cost;
+};
+typedef WasmResult<int32_t> EscrowResult;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+enum WasmTypes { WT_I32, WT_I64, WT_U8V };
+
+struct WasmImportFunc
+{
+    std::string name;
+    std::optional<WasmTypes> result;
+    std::vector<WasmTypes> params;
+    // void* udata = nullptr;
+    // wasm_func_callback_with_env_t
+    void* wrap = nullptr;
+    uint32_t gas = 0;
+};
+
+typedef std::pair<void*, WasmImportFunc> WasmUserData;
+typedef std::vector<WasmUserData> ImportVec;
+
+#define WASM_IMPORT_FUNC(v, f, ...) \
+    WasmImpFunc<f##_proto>(v, #f, reinterpret_cast<void*>(&f##_wrap), ##__VA_ARGS__)
+
+#define WASM_IMPORT_FUNC2(v, f, n, ...) \
+    WasmImpFunc<f##_proto>(v, n, reinterpret_cast<void*>(&f##_wrap), ##__VA_ARGS__)
+
+template <int N, int C, typename mpl>
+void
+WasmImpArgs(WasmImportFunc& e)
+{
+    if constexpr (N < C)
+    {
+        using at = typename boost::mpl::at_c<mpl, N>::type;
+        if constexpr (std::is_pointer_v<at>)
+            e.params.push_back(WT_I32);
+        else if constexpr (std::is_same_v<at, std::int32_t>)
+            e.params.push_back(WT_I32);
+        else if constexpr (std::is_same_v<at, std::int64_t>)
+            e.params.push_back(WT_I64);
+        else
+            static_assert(std::is_pointer_v<at>, "Unsupported argument type");
+
+        return WasmImpArgs<N + 1, C, mpl>(e);
+    }
+    return;
+}
+
+template <typename rt>
+void
+WasmImpRet(WasmImportFunc& e)
+{
+    if constexpr (std::is_pointer_v<rt>)
+        e.result = WT_I32;
+    else if constexpr (std::is_same_v<rt, std::int32_t>)
+        e.result = WT_I32;
+    else if constexpr (std::is_same_v<rt, std::int64_t>)
+        e.result = WT_I64;
+    else if constexpr (std::is_void_v<rt>)
+        e.result.reset();
+#if (defined(__GNUC__) && (__GNUC__ >= 14)) || \
+    ((defined(__clang_major__)) && (__clang_major__ >= 18))
+    else
+        static_assert(false, "Unsupported return type");
+#endif
+}
+
+template <typename F>
+void
+WasmImpFuncHelper(WasmImportFunc& e)
+{
+    using rt = typename bft::result_type<F>::type;
+    using pt = typename bft::parameter_types<F>::type;
+    // typename boost::mpl::at_c<mpl, N>::type
+
+    WasmImpRet<rt>(e);
+    WasmImpArgs<0, bft::function_arity<F>::value, pt>(e);
+    // WasmImpWrap(e, std::forward<F>(f));
+}
+
+template <typename F>
+void
+WasmImpFunc(
+    ImportVec& v,
+    std::string_view imp_name,
+    void* f_wrap,
+    void* data = nullptr,
+    uint32_t gas = 0)
+{
+    WasmImportFunc e;
+    e.name = imp_name;
+    e.wrap = f_wrap;
+    e.gas = gas;
+    WasmImpFuncHelper<F>(e);
+    v.push_back(std::make_pair(data, std::move(e)));
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+struct WasmParamVec
+{
+    std::uint8_t const* d = nullptr;
+    std::int32_t sz = 0;
+};
+
+struct WasmParam
+{
+    WasmTypes type = WT_I32;
+    union
+    {
+        std::int32_t i32;
+        std::int64_t i64 = 0;
+        float f32;
+        double f64;
+        WasmParamVec u8v;
+    } of;
+};
+
+template <class... Types>
+inline void
+wasmParamsHlp(std::vector<WasmParam>& v, std::int32_t p, Types&&... args)
+{
+    v.push_back({.type = WT_I32, .of = {.i32 = p}});
+    wasmParamsHlp(v, std::forward<Types>(args)...);
+}
+
+template <class... Types>
+inline void
+wasmParamsHlp(std::vector<WasmParam>& v, std::int64_t p, Types&&... args)
+{
+    v.push_back({.type = WT_I64, .of = {.i64 = p}});
+    wasmParamsHlp(v, std::forward<Types>(args)...);
+}
+
+// We are not supporting float/double for now
+// Leaving this code here so that it is easier to add later if needed
+// template <class... Types>
+// inline void
+// wasmParamsHlp(std::vector<WasmParam>& v, float p, Types&&... args)
+// {
+//     v.push_back({.type = WT_F32, .of = {.f32 = p}});
+//     wasmParamsHlp(v, std::forward<Types>(args)...);
+// }
+
+// template <class... Types>
+// inline void
+// wasmParamsHlp(std::vector<WasmParam>& v, double p, Types&&... args)
+// {
+//     v.push_back({.type = WT_F64, .of = {.f64 = p}});
+//     wasmParamsHlp(v, std::forward<Types>(args)...);
+// }
+
+inline void
+wasmParamsHlp(std::vector<WasmParam>& v)
+{
+    return;
+}
+
+template <class... Types>
+inline std::vector<WasmParam>
+wasmParams(Types&&... args)
+{
+    std::vector<WasmParam> v;
+    v.reserve(sizeof...(args));
+    wasmParamsHlp(v, std::forward<Types>(args)...);
+    return v;
+}
+
+template <typename T, size_t size = sizeof(T)>
+inline constexpr T
+adjustWasmEndianessHlp(T x)
+{
+    static_assert(std::is_integral<T>::value, "Only integral types");
+    if constexpr (size > 1)
+    {
+        using U = std::make_unsigned<T>::type;
+        U u = static_cast<U>(x);
+        U const low = (u & 0xFF) << ((size - 1) << 3);
+        u = adjustWasmEndianessHlp<U, size - 1>(u >> 8);
+        return static_cast<T>(low | u);
+    }
+
+    return x;
+}
+
+template <typename T, size_t size = sizeof(T)>
+inline constexpr T
+adjustWasmEndianess(T x)
+{
+    // LCOV_EXCL_START
+    static_assert(std::is_integral<T>::value, "Only integral types");
+    if constexpr (std::endian::native == std::endian::big)
+    {
+        return adjustWasmEndianessHlp(x);
+    }
+    return x;
+    // LCOV_EXCL_STOP
+}
+
+}  // namespace xrpl

include/xrpl/tx/wasm/README.md

@@ -0,0 +1,189 @@
+# WASM Module for Programmable Escrows
+
+This module provides WebAssembly (WASM) execution capabilities for programmable
+escrows on the XRP Ledger. When an escrow is finished, the WASM code runs to
+determine whether the escrow conditions are met, enabling custom programmable
+logic for escrow release conditions.
+
+For the full specification, see
+[XLS-0102: WASM VM](https://xls.xrpl.org/xls/XLS-0102-wasm-vm.html).
+
+## Architecture
+
+The module follows a layered architecture:
+
+```
+┌─────────────────────────────────────────────────────────────┐
+│                 WasmEngine (WasmVM.h)                       │
+│         runEscrowWasm(), preflightEscrowWasm()              │
+│              Host function registration                     │
+├─────────────────────────────────────────────────────────────┤
+│                 WasmiEngine (WasmiVM.h)                     │
+│            Low-level wasmi interpreter integration          │
+├─────────────────────────────────────────────────────────────┤
+│    HostFuncWrapper          │       HostFuncImpl            │
+│   C-style WASM bridges      │   C++ implementations         │
+├─────────────────────────────────────────────────────────────┤
+│                   HostFunc (Interface)                      │
+│            Abstract base class for host functions           │
+└─────────────────────────────────────────────────────────────┘
+```
+
+### Key Components
+
+- **`WasmVM.h` / `detail/WasmVM.cpp`** - High-level facade providing:
+  - `WasmEngine` singleton that wraps the underlying WASM interpreter
+  - `runEscrowWasm()` - Execute WASM code for escrow finish
+  - `preflightEscrowWasm()` - Validate WASM code during preflight
+  - `createWasmImport()` - Register all host functions
+
+- **`WasmiVM.h` / `detail/WasmiVM.cpp`** - Low-level integration with the
+  [wasmi](https://github.com/wasmi-labs/wasmi) WebAssembly interpreter:
+  - `WasmiEngine` - Manages WASM modules, instances, and execution
+  - Memory management and gas metering
+  - Function invocation and result handling
+
+- **`HostFunc.h`** - Abstract `HostFunctions` base class defining the interface
+  for all callable host functions. Each method returns
+  `Expected<T, HostFunctionError>`.
+
+- **`HostFuncImpl.h` / `detail/HostFuncImpl*.cpp`** - Concrete
+  `WasmHostFunctionsImpl` class that implements host functions with access to
+  `ApplyContext` for ledger state queries. Implementation split across files:
+  - `HostFuncImpl.cpp` - Core utilities (updateData, checkSignature, etc.)
+  - `HostFuncImplFloat.cpp` - Float/number arithmetic operations
+  - `HostFuncImplGetter.cpp` - Field access (transaction, ledger objects)
+  - `HostFuncImplKeylet.cpp` - Keylet construction functions
+  - `HostFuncImplLedgerHeader.cpp` - Ledger header info access
+  - `HostFuncImplNFT.cpp` - NFT-related queries
+  - `HostFuncImplTrace.cpp` - Debugging/tracing functions
+
+- **`HostFuncWrapper.h` / `detail/HostFuncWrapper.cpp`** - C-style wrapper
+  functions that bridge WASM calls to C++ `HostFunctions` methods. Each host
+  function has:
+  - A `_proto` type alias defining the function signature
+  - A `_wrap` function that extracts parameters and calls the implementation
+
+- **`ParamsHelper.h`** - Utilities for WASM parameter handling:
+  - `WASM_IMPORT_FUNC` / `WASM_IMPORT_FUNC2` macros for registration
+  - `wasmParams()` helper for building parameter vectors
+  - Type conversion between WASM and C++ types
+
+## Host Functions
+
+Host functions allow WASM code to interact with the XRP Ledger. They are
+organized into categories:
+
+- **Ledger Information** - Access ledger sequence, timestamps, hashes, fees
+- **Transaction & Ledger Object Access** - Read fields from the transaction
+  and ledger objects (including the current escrow object)
+- **Keylet Construction** - Build keylets to look up various ledger object types
+- **Cryptography** - Signature verification and hashing
+- **Float Arithmetic** - Mathematical operations for amount calculations
+- **NFT Operations** - Query NFT properties
+- **Tracing/Debugging** - Log messages for debugging
+
+For the complete list of available host functions, their WASM names, and gas
+costs, see the [XLS-0102 specification](https://xls.xrpl.org/xls/XLS-0102-wasm-vm.html)
+or `detail/WasmVM.cpp` where they are registered via `WASM_IMPORT_FUNC2` macros.
+For method signatures, see `HostFunc.h`.
+
+## Gas Model
+
+Each host function has an associated gas cost. The gas cost is specified when
+registering the function in `detail/WasmVM.cpp`:
+
+```cpp
+WASM_IMPORT_FUNC2(i, getLedgerSqn, "get_ledger_sqn", hfs, 60);
+//                                                        ^^ gas cost
+```
+
+WASM execution is metered, and if the gas limit is exceeded, execution fails.
+
+## Entry Point
+
+The WASM module must export a function with the name defined by
+`ESCROW_FUNCTION_NAME` (currently `"finish"`). This function:
+
+- Takes no parameters (or parameters passed via host function calls)
+- Returns an `int32_t`:
+  - `1` (or positive): Escrow conditions are met, allow finish
+  - `0` (or negative): Escrow conditions are not met, reject finish
+
+## Adding a New Host Function
+
+To add a new host function, follow these steps:
+
+### 1. Add to HostFunc.h (Base Class)
+
+Add a virtual method declaration with a default implementation that returns an
+error:
+
+```cpp
+virtual Expected<ReturnType, HostFunctionError>
+myNewFunction(ParamType1 param1, ParamType2 param2)
+{
+    return Unexpected(HostFunctionError::INTERNAL);
+}
+```
+
+### 2. Add to HostFuncImpl.h (Declaration)
+
+Add the method override declaration in `WasmHostFunctionsImpl`:
+
+```cpp
+Expected<ReturnType, HostFunctionError>
+myNewFunction(ParamType1 param1, ParamType2 param2) override;
+```
+
+### 3. Implement in detail/HostFuncImpl\*.cpp
+
+Add the implementation in the appropriate file:
+
+```cpp
+Expected<ReturnType, HostFunctionError>
+WasmHostFunctionsImpl::myNewFunction(ParamType1 param1, ParamType2 param2)
+{
+    // Implementation using ctx (ApplyContext) for ledger access
+    return result;
+}
+```
+
+### 4. Add Wrapper to HostFuncWrapper.h
+
+Add the prototype and wrapper declaration:
+
+```cpp
+using myNewFunction_proto = int32_t(uint8_t const*, int32_t, ...);
+wasm_trap_t*
+myNewFunction_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results);
+```
+
+### 5. Implement Wrapper in detail/HostFuncWrapper.cpp
+
+Implement the C-style wrapper that bridges WASM to C++:
+
+```cpp
+wasm_trap_t*
+myNewFunction_wrap(void* env, wasm_val_vec_t const* params, wasm_val_vec_t* results)
+{
+    // Extract parameters from params
+    // Call hfs->myNewFunction(...)
+    // Set results and return
+}
+```
+
+### 6. Register in WasmVM.cpp
+
+Add the function registration in `setCommonHostFunctions()` or
+`createWasmImport()`:
+
+```cpp
+WASM_IMPORT_FUNC2(i, myNewFunction, "my_new_function", hfs, 100);
+//                                   ^^ WASM name       ^^ gas cost
+```
+
+> [!IMPORTANT]
+> New host functions MUST be amendment-gated in `WasmVM.cpp`.
+> Wrap the registration in an amendment check to ensure the function is only
+> available after the corresponding amendment is enabled on the network.

include/xrpl/tx/wasm/WasmVM.h

@@ -0,0 +1,90 @@
+#pragma once
+
+#include <xrpl/tx/wasm/HostFunc.h>
+
+#include <string_view>
+
+namespace xrpl {
+
+static std::string_view const W_ENV = "env";
+static std::string_view const W_HOST_LIB = "host_lib";
+static std::string_view const W_MEM = "memory";
+static std::string_view const W_STORE = "store";
+static std::string_view const W_LOAD = "load";
+static std::string_view const W_SIZE = "size";
+static std::string_view const W_ALLOC = "allocate";
+static std::string_view const W_DEALLOC = "deallocate";
+static std::string_view const W_PROC_EXIT = "proc_exit";
+
+static std::string_view const ESCROW_FUNCTION_NAME = "finish";
+
+uint32_t const MAX_PAGES = 128;  // 8MB = 64KB*128
+
+class WasmiEngine;
+
+class WasmEngine
+{
+    std::unique_ptr<WasmiEngine> const impl_;
+
+    WasmEngine();
+
+    WasmEngine(WasmEngine const&) = delete;
+    WasmEngine(WasmEngine&&) = delete;
+    WasmEngine&
+    operator=(WasmEngine const&) = delete;
+    WasmEngine&
+    operator=(WasmEngine&&) = delete;
+
+public:
+    ~WasmEngine() = default;
+
+    static WasmEngine&
+    instance();
+
+    Expected<WasmResult<int32_t>, TER>
+    run(Bytes const& wasmCode,
+        HostFunctions& hfs,
+        int64_t gasLimit,
+        std::string_view funcName = {},
+        std::vector<WasmParam> const& params = {},
+        ImportVec const& imports = {},
+        beast::Journal j = beast::Journal{beast::Journal::getNullSink()});
+
+    NotTEC
+    check(
+        Bytes const& wasmCode,
+        HostFunctions& hfs,
+        std::string_view funcName,
+        std::vector<WasmParam> const& params = {},
+        ImportVec const& imports = {},
+        beast::Journal j = beast::Journal{beast::Journal::getNullSink()});
+
+    // Host functions helper functionality
+    void*
+    newTrap(std::string const& txt = std::string());
+
+    beast::Journal
+    getJournal() const;
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+ImportVec
+createWasmImport(HostFunctions& hfs);
+
+Expected<EscrowResult, TER>
+runEscrowWasm(
+    Bytes const& wasmCode,
+    HostFunctions& hfs,
+    int64_t gasLimit,
+    std::string_view funcName = ESCROW_FUNCTION_NAME,
+    std::vector<WasmParam> const& params = {});
+
+NotTEC
+preflightEscrowWasm(
+    Bytes const& wasmCode,
+    HostFunctions& hfs,
+    std::string_view funcName = ESCROW_FUNCTION_NAME,
+    std::vector<WasmParam> const& params = {});
+
+}  // namespace xrpl

include/xrpl/tx/wasm/WasmiVM.h

@@ -0,0 +1,321 @@
+#pragma once
+
+#include <xrpl/tx/wasm/WasmVM.h>
+
+#include <wasm.h>
+#include <wasmi.h>
+
+namespace xrpl {
+
+template <class T, void (*Create)(T*, size_t), void (*Destroy)(T*)>
+struct WasmVec
+{
+    T vec_;
+
+    WasmVec(size_t s = 0) : vec_ WASM_EMPTY_VEC
+    {
+        if (s > 0)
+            Create(&vec_, s);  // zeroes memory
+    }
+
+    ~WasmVec()
+    {
+        clear();
+    }
+
+    WasmVec(WasmVec const&) = delete;
+    WasmVec&
+    operator=(WasmVec const&) = delete;
+
+    WasmVec(WasmVec&& other) noexcept : vec_ WASM_EMPTY_VEC
+    {
+        *this = std::move(other);
+    }
+
+    WasmVec&
+    operator=(WasmVec&& other) noexcept
+    {
+        if (this != &other)
+        {
+            clear();
+            vec_ = other.vec_;
+            other.vec_ = WASM_EMPTY_VEC;
+        }
+        return *this;
+    }
+
+    void
+    clear()
+    {
+        Destroy(&vec_);  // call destructor for every elements too
+        vec_ = WASM_EMPTY_VEC;
+    }
+
+    T
+    release()
+    {
+        T result = vec_;
+        vec_ = WASM_EMPTY_VEC;
+        return result;
+    }
+};
+
+using WasmValtypeVec =
+    WasmVec<wasm_valtype_vec_t, &wasm_valtype_vec_new_uninitialized, &wasm_valtype_vec_delete>;
+using WasmValVec = WasmVec<wasm_val_vec_t, &wasm_val_vec_new_uninitialized, &wasm_val_vec_delete>;
+using WasmExternVec =
+    WasmVec<wasm_extern_vec_t, &wasm_extern_vec_new_uninitialized, &wasm_extern_vec_delete>;
+using WasmExporttypeVec = WasmVec<
+    wasm_exporttype_vec_t,
+    &wasm_exporttype_vec_new_uninitialized,
+    &wasm_exporttype_vec_delete>;
+using WasmImporttypeVec = WasmVec<
+    wasm_importtype_vec_t,
+    &wasm_importtype_vec_new_uninitialized,
+    &wasm_importtype_vec_delete>;
+
+struct WasmiResult
+{
+    WasmValVec r;
+    bool f;  // failure flag
+
+    WasmiResult(unsigned N = 0) : r(N), f(false)
+    {
+    }
+
+    ~WasmiResult() = default;
+    WasmiResult(WasmiResult&& o) = default;
+    WasmiResult&
+    operator=(WasmiResult&& o) = default;
+};
+
+using ModulePtr = std::unique_ptr<wasm_module_t, decltype(&wasm_module_delete)>;
+using InstancePtr = std::unique_ptr<wasm_instance_t, decltype(&wasm_instance_delete)>;
+using EnginePtr = std::unique_ptr<wasm_engine_t, decltype(&wasm_engine_delete)>;
+using StorePtr = std::unique_ptr<wasm_store_t, decltype(&wasm_store_delete)>;
+
+using FuncInfo = std::pair<wasm_func_t const*, wasm_functype_t const*>;
+
+struct InstanceWrapper
+{
+    wasm_store_t* store_ = nullptr;
+    WasmExternVec exports_;
+    mutable int memIdx_ = -1;
+    InstancePtr instance_;
+    beast::Journal j_ = beast::Journal(beast::Journal::getNullSink());
+
+private:
+    static InstancePtr
+    init(
+        StorePtr& s,
+        ModulePtr& m,
+        WasmExternVec& expt,
+        WasmExternVec const& imports,
+        beast::Journal j);
+
+public:
+    InstanceWrapper();
+
+    InstanceWrapper(InstanceWrapper&& o);
+
+    InstanceWrapper&
+    operator=(InstanceWrapper&& o);
+
+    InstanceWrapper(StorePtr& s, ModulePtr& m, WasmExternVec const& imports, beast::Journal j);
+
+    ~InstanceWrapper() = default;
+
+    operator bool() const;
+
+    FuncInfo
+    getFunc(std::string_view funcName, WasmExporttypeVec const& exportTypes) const;
+
+    wmem
+    getMem() const;
+
+    std::int64_t
+    getGas() const;
+
+    std::int64_t
+    setGas(std::int64_t) const;
+};
+
+struct ModuleWrapper
+{
+    ModulePtr module_;
+    InstanceWrapper instanceWrap_;
+    WasmExporttypeVec exportTypes_;
+    beast::Journal j_ = beast::Journal(beast::Journal::getNullSink());
+
+private:
+    static ModulePtr
+    init(StorePtr& s, Bytes const& wasmBin, beast::Journal j);
+
+public:
+    ModuleWrapper();
+    ModuleWrapper(ModuleWrapper&& o);
+    ModuleWrapper&
+    operator=(ModuleWrapper&& o);
+    ModuleWrapper(
+        StorePtr& s,
+        Bytes const& wasmBin,
+        bool instantiate,
+        ImportVec const& imports,
+        beast::Journal j);
+    ~ModuleWrapper() = default;
+
+    operator bool() const;
+
+    FuncInfo
+    getFunc(std::string_view funcName) const;
+
+    wasm_functype_t*
+    getFuncType(std::string_view funcName) const;
+
+    wmem
+    getMem() const;
+
+    InstanceWrapper const&
+    getInstance(int i = 0) const;
+
+    int
+    addInstance(StorePtr& s, WasmExternVec const& imports);
+
+    std::int64_t
+    getGas();
+
+private:
+    WasmExternVec
+    buildImports(StorePtr& s, ImportVec const& imports);
+};
+
+class WasmiEngine
+{
+    EnginePtr engine_;
+    StorePtr store_;
+    std::unique_ptr<ModuleWrapper> moduleWrap_;
+    beast::Journal j_ = beast::Journal(beast::Journal::getNullSink());
+
+    std::mutex m_;  // 1 instance mutex
+
+public:
+    WasmiEngine();
+    ~WasmiEngine() = default;
+
+    static EnginePtr
+    init();
+
+    Expected<WasmResult<int32_t>, TER>
+    run(Bytes const& wasmCode,
+        HostFunctions& hfs,
+        int64_t gas,
+        std::string_view funcName,
+        std::vector<WasmParam> const& params,
+        ImportVec const& imports,
+        beast::Journal j);
+
+    NotTEC
+    check(
+        Bytes const& wasmCode,
+        HostFunctions& hfs,
+        std::string_view funcName,
+        std::vector<WasmParam> const& params,
+        ImportVec const& imports,
+        beast::Journal j);
+
+    std::int64_t
+    getGas() const;
+
+    // Host functions helper functionality
+    wasm_trap_t*
+    newTrap(std::string const& msg);
+
+    beast::Journal
+    getJournal() const;
+
+private:
+    InstanceWrapper const&
+    getRT(int m = 0, int i = 0) const;
+
+    wmem
+    getMem() const;
+
+    Expected<WasmResult<int32_t>, TER>
+    runHlp(
+        Bytes const& wasmCode,
+        HostFunctions& hfs,
+        int64_t gas,
+        std::string_view funcName,
+        std::vector<WasmParam> const& params,
+        ImportVec const& imports);
+
+    NotTEC
+    checkHlp(
+        Bytes const& wasmCode,
+        HostFunctions& hfs,
+        std::string_view funcName,
+        std::vector<WasmParam> const& params,
+        ImportVec const& imports);
+
+    int
+    addModule(Bytes const& wasmCode, bool instantiate, ImportVec const& imports, int64_t gas);
+    void
+    clearModules();
+
+    // int  addInstance();
+
+    int32_t
+    runFunc(std::string_view const funcName, int32_t p);
+
+    int32_t
+    makeModule(Bytes const& wasmCode, WasmExternVec const& imports = {});
+
+    FuncInfo
+    getFunc(std::string_view funcName) const;
+
+    std::vector<wasm_val_t>
+    convertParams(std::vector<WasmParam> const& params);
+
+    static int
+    compareParamTypes(wasm_valtype_vec_t const* ftp, std::vector<wasm_val_t> const& p);
+
+    static void
+    add_param(std::vector<wasm_val_t>& in, int32_t p);
+    static void
+    add_param(std::vector<wasm_val_t>& in, int64_t p);
+
+    template <int NR, class... Types>
+    inline WasmiResult
+    call(std::string_view func, Types&&... args);
+
+    template <int NR, class... Types>
+    inline WasmiResult
+    call(FuncInfo const& f, Types&&... args);
+
+    template <int NR, class... Types>
+    inline WasmiResult
+    call(FuncInfo const& f, std::vector<wasm_val_t>& in);
+
+    template <int NR, class... Types>
+    inline WasmiResult
+    call(FuncInfo const& f, std::vector<wasm_val_t>& in, std::int32_t p, Types&&... args);
+
+    template <int NR, class... Types>
+    inline WasmiResult
+    call(FuncInfo const& f, std::vector<wasm_val_t>& in, std::int64_t p, Types&&... args);
+
+    template <int NR, class... Types>
+    inline WasmiResult
+    call(
+        FuncInfo const& f,
+        std::vector<wasm_val_t>& in,
+        uint8_t const* d,
+        int32_t sz,
+        Types&&... args);
+
+    template <int NR, class... Types>
+    inline WasmiResult
+    call(FuncInfo const& f, std::vector<wasm_val_t>& in, Bytes const& p, Types&&... args);
+};
+
+}  // namespace xrpl

src/libxrpl/basics/Number.cpp

@@ -945,6 +945,73 @@ power(Number const& f, unsigned n)
     return r;
 }
 
+// Series expansion method approximation of ln(x)
+static Number
+ln(Number const& x, int iterations = 50)
+{
+    static Number const N0(0);
+    static Number const N2(2, 0);
+    static Number const N05(5, -1);
+    static Number const LN2(693'147'180'559'945'309ll, -18);
+
+    if (x <= 0)
+        throw std::runtime_error("Not a positive value");
+    else if (x == 1)
+        return N0;
+
+    int exponent = 0;
+    Number mantissa = x;
+
+    while (mantissa >= N2)
+    {
+        mantissa /= 2;
+        exponent += 1;
+    }
+    while (mantissa < N05)
+    {
+        mantissa *= 2;
+        exponent -= 1;
+    }
+
+    Number z = (mantissa - 1) / (mantissa + 1);
+    Number const zz = z * z;
+    Number sum;
+
+    for (int i = 1; i <= iterations; ++i)
+    {
+        sum = sum + z / (2 * i - 1);
+        z = z * zz;
+    }
+
+    return 2 * sum + exponent * LN2;
+}
+
+Number
+log10(Number const& x, int iterations)
+{
+    static Number const N0(0);
+    static Number const LN10(2'302'585'092'994'046ll, -15);
+
+    if (x <= 0)
+        throw std::runtime_error("Not a positive value");
+    else if (x == 1)
+        return N0;
+
+    if (x <= Number(10))
+    {
+        auto const r = ln(x, iterations) / LN10;
+        return r;
+    }
+
+    // (1 <= normalX < 10)
+    // ln(x) = ln(normalX * 10^norm) = ln(normalX) + norm * ln(10)
+    int diffExp = 15 + x.exponent();
+    Number const normalX = x / Number(1, diffExp);
+    auto const lnX = ln(normalX, iterations) + diffExp * LN10;
+    auto const lgX = lnX / LN10;
+    return lgX;
+}
+
 // Returns f^(1/d)
 // Uses Newton–Raphson iterations until the result stops changing
 // to find the non-negative root of the polynomial g(x) = x^d - f

src/libxrpl/ledger/AcceptedLedgerTx.cpp

@@ -2,6 +2,7 @@
 #include <xrpl/basics/StringUtilities.h>
 #include <xrpl/ledger/AcceptedLedgerTx.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/UintTypes.h>
 #include <xrpl/protocol/jss.h>
 

src/libxrpl/ledger/ApplyStateTable.cpp

@@ -89,6 +89,8 @@ ApplyStateTable::apply(
     TER ter,
     std::optional<STAmount> const& deliver,
     std::optional<uint256 const> const& parentBatchId,
+    std::optional<std::uint32_t> const& gasUsed,
+    std::optional<std::int32_t> const& wasmReturnCode,
     bool isDryRun,
     beast::Journal j)
 {
@@ -103,6 +105,8 @@ ApplyStateTable::apply(
 
         meta.setDeliveredAmount(deliver);
         meta.setParentBatchID(parentBatchId);
+        meta.setGasUsed(gasUsed);
+        meta.setWasmReturnCode(wasmReturnCode);
 
         Mods newMod;
         for (auto& item : items_)

src/libxrpl/ledger/ApplyViewImpl.cpp

@@ -15,7 +15,8 @@ ApplyViewImpl::apply(
     bool isDryRun,
     beast::Journal j)
 {
-    return items_.apply(to, tx, ter, deliver_, parentBatchId, isDryRun, j);
+    return items_.apply(
+        to, tx, ter, deliver_, parentBatchId, gasUsed_, wasmReturnCode_, isDryRun, j);
 }
 
 std::size_t

src/libxrpl/ledger/BookDirs.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/ledger/BookDirs.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/Indexes.h>
 
 namespace xrpl {

src/libxrpl/ledger/Credit.cpp

@@ -1,60 +0,0 @@
-#include <xrpl/ledger/ReadView.h>
-#include <xrpl/protocol/AmountConversions.h>
-#include <xrpl/protocol/Indexes.h>
-#include <xrpl/protocol/STAmount.h>
-
-namespace xrpl {
-
-STAmount
-creditLimit(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency)
-{
-    STAmount result(Issue{currency, account});
-
-    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
-
-    if (sleRippleState)
-    {
-        result = sleRippleState->getFieldAmount(account < issuer ? sfLowLimit : sfHighLimit);
-        result.setIssuer(account);
-    }
-
-    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditLimit : result issuer match");
-    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditLimit : result currency match");
-    return result;
-}
-
-IOUAmount
-creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur)
-{
-    return toAmount<IOUAmount>(creditLimit(v, acc, iss, cur));
-}
-
-STAmount
-creditBalance(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency)
-{
-    STAmount result(Issue{currency, account});
-
-    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
-
-    if (sleRippleState)
-    {
-        result = sleRippleState->getFieldAmount(sfBalance);
-        if (account < issuer)
-            result.negate();
-        result.setIssuer(account);
-    }
-
-    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditBalance : result issuer match");
-    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditBalance : result currency match");
-    return result;
-}
-
-}  // namespace xrpl

src/libxrpl/ledger/helpers/AccountRootHelpers.cpp

@@ -0,0 +1,247 @@
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+//
+#include <xrpl/basics/Log.h>
+#include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/digest.h>
+
+#include <algorithm>
+#include <limits>
+
+namespace xrpl {
+
+bool
+isGlobalFrozen(ReadView const& view, AccountID const& issuer)
+{
+    if (isXRP(issuer))
+        return false;
+    if (auto const sle = view.read(keylet::account(issuer)))
+        return sle->isFlag(lsfGlobalFreeze);
+    return false;
+}
+
+// An owner count cannot be negative. If adjustment would cause a negative
+// owner count, clamp the owner count at 0. Similarly for overflow. This
+// adjustment allows the ownerCount to be adjusted up or down in multiple steps.
+// If id != std::nullopt, then do error reporting.
+//
+// Returns adjusted owner count.
+static std::uint32_t
+confineOwnerCount(
+    std::uint32_t current,
+    std::int32_t adjustment,
+    std::optional<AccountID> const& id = std::nullopt,
+    beast::Journal j = beast::Journal{beast::Journal::getNullSink()})
+{
+    std::uint32_t adjusted{current + adjustment};
+    if (adjustment > 0)
+    {
+        // Overflow is well defined on unsigned
+        if (adjusted < current)
+        {
+            if (id)
+            {
+                JLOG(j.fatal()) << "Account " << *id << " owner count exceeds max!";
+            }
+            adjusted = std::numeric_limits<std::uint32_t>::max();
+        }
+    }
+    else
+    {
+        // Underflow is well defined on unsigned
+        if (adjusted > current)
+        {
+            if (id)
+            {
+                JLOG(j.fatal()) << "Account " << *id << " owner count set below 0!";
+            }
+            adjusted = 0;
+            XRPL_ASSERT(!id, "xrpl::confineOwnerCount : id is not set");
+        }
+    }
+    return adjusted;
+}
+
+XRPAmount
+xrpLiquid(ReadView const& view, AccountID const& id, std::int32_t ownerCountAdj, beast::Journal j)
+{
+    auto const sle = view.read(keylet::account(id));
+    if (sle == nullptr)
+        return beast::zero;
+
+    // Return balance minus reserve
+    std::uint32_t const ownerCount =
+        confineOwnerCount(view.ownerCountHook(id, sle->getFieldU32(sfOwnerCount)), ownerCountAdj);
+
+    // Pseudo-accounts have no reserve requirement
+    auto const reserve =
+        isPseudoAccount(sle) ? XRPAmount{0} : view.fees().accountReserve(ownerCount);
+
+    auto const fullBalance = sle->getFieldAmount(sfBalance);
+
+    auto const balance = view.balanceHook(id, xrpAccount(), fullBalance);
+
+    STAmount const amount = (balance < reserve) ? STAmount{0} : balance - reserve;
+
+    JLOG(j.trace()) << "accountHolds:" << " account=" << to_string(id)
+                    << " amount=" << amount.getFullText()
+                    << " fullBalance=" << fullBalance.getFullText()
+                    << " balance=" << balance.getFullText() << " reserve=" << reserve
+                    << " ownerCount=" << ownerCount << " ownerCountAdj=" << ownerCountAdj;
+
+    return amount.xrp();
+}
+
+Rate
+transferRate(ReadView const& view, AccountID const& issuer)
+{
+    auto const sle = view.read(keylet::account(issuer));
+
+    if (sle && sle->isFieldPresent(sfTransferRate))
+        return Rate{sle->getFieldU32(sfTransferRate)};
+
+    return parityRate;
+}
+
+void
+adjustOwnerCount(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sle,
+    std::int32_t amount,
+    beast::Journal j)
+{
+    if (!sle)
+        return;
+    XRPL_ASSERT(amount, "xrpl::adjustOwnerCount : nonzero amount input");
+    std::uint32_t const current{sle->getFieldU32(sfOwnerCount)};
+    AccountID const id = (*sle)[sfAccount];
+    std::uint32_t const adjusted = confineOwnerCount(current, amount, id, j);
+    view.adjustOwnerCountHook(id, current, adjusted);
+    sle->at(sfOwnerCount) = adjusted;
+    view.update(sle);
+}
+
+AccountID
+pseudoAccountAddress(ReadView const& view, uint256 const& pseudoOwnerKey)
+{
+    // This number must not be changed without an amendment
+    constexpr std::uint16_t maxAccountAttempts = 256;
+    for (std::uint16_t i = 0; i < maxAccountAttempts; ++i)
+    {
+        ripesha_hasher rsh;
+        auto const hash = sha512Half(i, view.header().parentHash, pseudoOwnerKey);
+        rsh(hash.data(), hash.size());
+        AccountID const ret{static_cast<ripesha_hasher::result_type>(rsh)};
+        if (!view.read(keylet::account(ret)))
+            return ret;
+    }
+    return beast::zero;
+}
+
+// Pseudo-account designator fields MUST be maintained by including the
+// SField::sMD_PseudoAccount flag in the SField definition. (Don't forget to
+// "| SField::sMD_Default"!) The fields do NOT need to be amendment-gated,
+// since a non-active amendment will not set any field, by definition.
+// Specific properties of a pseudo-account are NOT checked here, that's what
+// InvariantCheck is for.
+[[nodiscard]] std::vector<SField const*> const&
+getPseudoAccountFields()
+{
+    static std::vector<SField const*> const pseudoFields = []() {
+        auto const ar = LedgerFormats::getInstance().findByType(ltACCOUNT_ROOT);
+        if (!ar)
+        {
+            // LCOV_EXCL_START
+            LogicError(
+                "xrpl::getPseudoAccountFields : unable to find account root "
+                "ledger format");
+            // LCOV_EXCL_STOP
+        }
+        auto const& soTemplate = ar->getSOTemplate();
+
+        std::vector<SField const*> pseudoFields;
+        for (auto const& field : soTemplate)
+        {
+            if (field.sField().shouldMeta(SField::sMD_PseudoAccount))
+                pseudoFields.emplace_back(&field.sField());
+        }
+        return pseudoFields;
+    }();
+    return pseudoFields;
+}
+
+[[nodiscard]] bool
+isPseudoAccount(
+    std::shared_ptr<SLE const> sleAcct,
+    std::set<SField const*> const& pseudoFieldFilter)
+{
+    auto const& fields = getPseudoAccountFields();
+
+    // Intentionally use defensive coding here because it's cheap and makes the
+    // semantics of true return value clean.
+    return sleAcct && sleAcct->getType() == ltACCOUNT_ROOT &&
+        std::count_if(
+            fields.begin(), fields.end(), [&sleAcct, &pseudoFieldFilter](SField const* sf) -> bool {
+                return sleAcct->isFieldPresent(*sf) &&
+                    (pseudoFieldFilter.empty() || pseudoFieldFilter.contains(sf));
+            }) > 0;
+}
+
+Expected<std::shared_ptr<SLE>, TER>
+createPseudoAccount(ApplyView& view, uint256 const& pseudoOwnerKey, SField const& ownerField)
+{
+    [[maybe_unused]]
+    auto const& fields = getPseudoAccountFields();
+    XRPL_ASSERT(
+        std::count_if(
+            fields.begin(),
+            fields.end(),
+            [&ownerField](SField const* sf) -> bool { return *sf == ownerField; }) == 1,
+        "xrpl::createPseudoAccount : valid owner field");
+
+    auto const accountId = pseudoAccountAddress(view, pseudoOwnerKey);
+    if (accountId == beast::zero)
+        return Unexpected(tecDUPLICATE);
+
+    // Create pseudo-account.
+    auto account = std::make_shared<SLE>(keylet::account(accountId));
+    account->setAccountID(sfAccount, accountId);
+    account->setFieldAmount(sfBalance, STAmount{});
+
+    // Pseudo-accounts can't submit transactions, so set the sequence number
+    // to 0 to make them easier to spot and verify, and add an extra level
+    // of protection.
+    std::uint32_t const seqno =                           //
+        view.rules().enabled(featureSingleAssetVault) ||  //
+            view.rules().enabled(featureLendingProtocol)  //
+        ? 0                                               //
+        : view.seq();
+    account->setFieldU32(sfSequence, seqno);
+    // Ignore reserves requirement, disable the master key, allow default
+    // rippling, and enable deposit authorization to prevent payments into
+    // pseudo-account.
+    account->setFieldU32(sfFlags, lsfDisableMaster | lsfDefaultRipple | lsfDepositAuth);
+    // Link the pseudo-account with its owner object.
+    account->setFieldH256(ownerField, pseudoOwnerKey);
+
+    view.insert(account);
+
+    return account;
+}
+
+[[nodiscard]] TER
+checkDestinationAndTag(SLE::const_ref toSle, bool hasDestinationTag)
+{
+    if (toSle == nullptr)
+        return tecNO_DST;
+
+    // The tag is basically account-specific information we don't
+    // understand, but we can require someone to fill it in.
+    if (toSle->isFlag(lsfRequireDestTag) && !hasDestinationTag)
+        return tecDST_TAG_NEEDED;  // Cannot send without a tag
+
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/CredentialHelpers.cpp

@@ -1,5 +1,7 @@
-#include <xrpl/ledger/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+//
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/digest.h>
 

src/libxrpl/ledger/helpers/DirectoryHelpers.cpp

@@ -0,0 +1,177 @@
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+//
+#include <xrpl/protocol/LedgerFormats.h>
+
+namespace xrpl {
+
+bool
+dirFirst(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirFirst(view, root, page, index, entry);
+}
+
+bool
+dirNext(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirNext(view, root, page, index, entry);
+}
+
+bool
+cdirFirst(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirFirst(view, root, page, index, entry);
+}
+
+bool
+cdirNext(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirNext(view, root, page, index, entry);
+}
+
+void
+forEachItem(
+    ReadView const& view,
+    Keylet const& root,
+    std::function<void(std::shared_ptr<SLE const> const&)> const& f)
+{
+    XRPL_ASSERT(root.type == ltDIR_NODE, "xrpl::forEachItem : valid root type");
+
+    if (root.type != ltDIR_NODE)
+        return;
+
+    auto pos = root;
+
+    while (true)
+    {
+        auto sle = view.read(pos);
+        if (!sle)
+            return;
+        for (auto const& key : sle->getFieldV256(sfIndexes))
+            f(view.read(keylet::child(key)));
+        auto const next = sle->getFieldU64(sfIndexNext);
+        if (!next)
+            return;
+        pos = keylet::page(root, next);
+    }
+}
+
+bool
+forEachItemAfter(
+    ReadView const& view,
+    Keylet const& root,
+    uint256 const& after,
+    std::uint64_t const hint,
+    unsigned int limit,
+    std::function<bool(std::shared_ptr<SLE const> const&)> const& f)
+{
+    XRPL_ASSERT(root.type == ltDIR_NODE, "xrpl::forEachItemAfter : valid root type");
+
+    if (root.type != ltDIR_NODE)
+        return false;
+
+    auto currentIndex = root;
+
+    // If startAfter is not zero try jumping to that page using the hint
+    if (after.isNonZero())
+    {
+        auto const hintIndex = keylet::page(root, hint);
+
+        if (auto hintDir = view.read(hintIndex))
+        {
+            for (auto const& key : hintDir->getFieldV256(sfIndexes))
+            {
+                if (key == after)
+                {
+                    // We found the hint, we can start here
+                    currentIndex = hintIndex;
+                    break;
+                }
+            }
+        }
+
+        bool found = false;
+        for (;;)
+        {
+            auto const ownerDir = view.read(currentIndex);
+            if (!ownerDir)
+                return found;
+            for (auto const& key : ownerDir->getFieldV256(sfIndexes))
+            {
+                if (!found)
+                {
+                    if (key == after)
+                        found = true;
+                }
+                else if (f(view.read(keylet::child(key))) && limit-- <= 1)
+                {
+                    return found;
+                }
+            }
+
+            auto const uNodeNext = ownerDir->getFieldU64(sfIndexNext);
+            if (uNodeNext == 0)
+                return found;
+            currentIndex = keylet::page(root, uNodeNext);
+        }
+    }
+    else
+    {
+        for (;;)
+        {
+            auto const ownerDir = view.read(currentIndex);
+            if (!ownerDir)
+                return true;
+            for (auto const& key : ownerDir->getFieldV256(sfIndexes))
+            {
+                if (f(view.read(keylet::child(key))) && limit-- <= 1)
+                    return true;
+            }
+            auto const uNodeNext = ownerDir->getFieldU64(sfIndexNext);
+            if (uNodeNext == 0)
+                return true;
+            currentIndex = keylet::page(root, uNodeNext);
+        }
+    }
+}
+
+bool
+dirIsEmpty(ReadView const& view, Keylet const& k)
+{
+    auto const sleNode = view.read(k);
+    if (!sleNode)
+        return true;
+    if (!sleNode->getFieldV256(sfIndexes).empty())
+        return false;
+    // The first page of a directory may legitimately be empty even if there
+    // are other pages (the first page is the anchor page) so check to see if
+    // there is another page. If there is, the directory isn't empty.
+    return sleNode->getFieldU64(sfIndexNext) == 0;
+}
+
+std::function<void(SLE::ref)>
+describeOwnerDir(AccountID const& account)
+{
+    return [account](std::shared_ptr<SLE> const& sle) { (*sle)[sfOwner] = account; };
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/MPTokenHelpers.cpp

@@ -0,0 +1,766 @@
+#include <xrpl/ledger/helpers/MPTokenHelpers.h>
+//
+#include <xrpl/basics/Log.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/SField.h>
+#include <xrpl/protocol/TxFlags.h>
+
+namespace xrpl {
+
+// Forward declarations for functions that remain in View.h/cpp
+bool
+isVaultPseudoAccountFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    MPTIssue const& mptShare,
+    int depth);
+
+[[nodiscard]] TER
+dirLink(
+    ApplyView& view,
+    AccountID const& owner,
+    std::shared_ptr<SLE>& object,
+    SF_UINT64 const& node = sfOwnerNode);
+
+bool
+isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue)
+{
+    if (auto const sle = view.read(keylet::mptIssuance(mptIssue.getMptID())))
+        return sle->isFlag(lsfMPTLocked);
+    return false;
+}
+
+bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue)
+{
+    if (auto const sle = view.read(keylet::mptoken(mptIssue.getMptID(), account)))
+        return sle->isFlag(lsfMPTLocked);
+    return false;
+}
+
+bool
+isFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue, int depth)
+{
+    return isGlobalFrozen(view, mptIssue) || isIndividualFrozen(view, account, mptIssue) ||
+        isVaultPseudoAccountFrozen(view, account, mptIssue, depth);
+}
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    MPTIssue const& mptIssue,
+    int depth)
+{
+    if (isGlobalFrozen(view, mptIssue))
+        return true;
+
+    for (auto const& account : accounts)
+    {
+        if (isIndividualFrozen(view, account, mptIssue))
+            return true;
+    }
+
+    for (auto const& account : accounts)
+    {
+        if (isVaultPseudoAccountFrozen(view, account, mptIssue, depth))
+            return true;
+    }
+
+    return false;
+}
+
+Rate
+transferRate(ReadView const& view, MPTID const& issuanceID)
+{
+    // fee is 0-50,000 (0-50%), rate is 1,000,000,000-2,000,000,000
+    // For example, if transfer fee is 50% then 10,000 * 50,000 = 500,000
+    // which represents 50% of 1,000,000,000
+    if (auto const sle = view.read(keylet::mptIssuance(issuanceID));
+        sle && sle->isFieldPresent(sfTransferFee))
+        return Rate{1'000'000'000u + 10'000 * sle->getFieldU16(sfTransferFee)};
+
+    return parityRate;
+}
+
+[[nodiscard]] TER
+canAddHolding(ReadView const& view, MPTIssue const& mptIssue)
+{
+    auto mptID = mptIssue.getMptID();
+    auto issuance = view.read(keylet::mptIssuance(mptID));
+    if (!issuance)
+    {
+        return tecOBJECT_NOT_FOUND;
+    }
+    if (!issuance->isFlag(lsfMPTCanTransfer))
+    {
+        return tecNO_AUTH;
+    }
+
+    return tesSUCCESS;
+}
+
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    MPTIssue const& mptIssue,
+    beast::Journal journal)
+{
+    auto const& mptID = mptIssue.getMptID();
+    auto const mpt = view.peek(keylet::mptIssuance(mptID));
+    if (!mpt)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+    if (mpt->isFlag(lsfMPTLocked))
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+    if (view.peek(keylet::mptoken(mptID, accountID)))
+        return tecDUPLICATE;
+    if (accountID == mptIssue.getIssuer())
+        return tesSUCCESS;
+
+    return authorizeMPToken(view, priorBalance, mptID, accountID, journal);
+}
+
+[[nodiscard]] TER
+authorizeMPToken(
+    ApplyView& view,
+    XRPAmount const& priorBalance,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    beast::Journal journal,
+    std::uint32_t flags,
+    std::optional<AccountID> holderID)
+{
+    auto const sleAcct = view.peek(keylet::account(account));
+    if (!sleAcct)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    // If the account that submitted the tx is a holder
+    // Note: `account_` is holder's account
+    //       `holderID` is NOT used
+    if (!holderID)
+    {
+        // When a holder wants to unauthorize/delete a MPT, the ledger must
+        //      - delete mptokenKey from owner directory
+        //      - delete the MPToken
+        if (flags & tfMPTUnauthorize)
+        {
+            auto const mptokenKey = keylet::mptoken(mptIssuanceID, account);
+            auto const sleMpt = view.peek(mptokenKey);
+            if (!sleMpt || (*sleMpt)[sfMPTAmount] != 0)
+                return tecINTERNAL;  // LCOV_EXCL_LINE
+
+            if (!view.dirRemove(
+                    keylet::ownerDir(account), (*sleMpt)[sfOwnerNode], sleMpt->key(), false))
+                return tecINTERNAL;  // LCOV_EXCL_LINE
+
+            adjustOwnerCount(view, sleAcct, -1, journal);
+
+            view.erase(sleMpt);
+            return tesSUCCESS;
+        }
+
+        // A potential holder wants to authorize/hold a mpt, the ledger must:
+        //      - add the new mptokenKey to the owner directory
+        //      - create the MPToken object for the holder
+
+        // The reserve that is required to create the MPToken. Note
+        // that although the reserve increases with every item
+        // an account owns, in the case of MPTokens we only
+        // *enforce* a reserve if the user owns more than two
+        // items. This is similar to the reserve requirements of trust lines.
+        std::uint32_t const uOwnerCount = sleAcct->getFieldU32(sfOwnerCount);
+        XRPAmount const reserveCreate(
+            (uOwnerCount < 2) ? XRPAmount(beast::zero)
+                              : view.fees().accountReserve(uOwnerCount + 1));
+
+        if (priorBalance < reserveCreate)
+            return tecINSUFFICIENT_RESERVE;
+
+        // Defensive check before we attempt to create MPToken for the issuer
+        auto const mpt = view.read(keylet::mptIssuance(mptIssuanceID));
+        if (!mpt || mpt->getAccountID(sfIssuer) == account)
+        {
+            // LCOV_EXCL_START
+            UNREACHABLE("xrpl::authorizeMPToken : invalid issuance or issuers token");
+            if (view.rules().enabled(featureLendingProtocol))
+                return tecINTERNAL;
+            // LCOV_EXCL_STOP
+        }
+
+        auto const mptokenKey = keylet::mptoken(mptIssuanceID, account);
+        auto mptoken = std::make_shared<SLE>(mptokenKey);
+        if (auto ter = dirLink(view, account, mptoken))
+            return ter;  // LCOV_EXCL_LINE
+
+        (*mptoken)[sfAccount] = account;
+        (*mptoken)[sfMPTokenIssuanceID] = mptIssuanceID;
+        (*mptoken)[sfFlags] = 0;
+        view.insert(mptoken);
+
+        // Update owner count.
+        adjustOwnerCount(view, sleAcct, 1, journal);
+
+        return tesSUCCESS;
+    }
+
+    auto const sleMptIssuance = view.read(keylet::mptIssuance(mptIssuanceID));
+    if (!sleMptIssuance)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    // If the account that submitted this tx is the issuer of the MPT
+    // Note: `account_` is issuer's account
+    //       `holderID` is holder's account
+    if (account != (*sleMptIssuance)[sfIssuer])
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const sleMpt = view.peek(keylet::mptoken(mptIssuanceID, *holderID));
+    if (!sleMpt)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    std::uint32_t const flagsIn = sleMpt->getFieldU32(sfFlags);
+    std::uint32_t flagsOut = flagsIn;
+
+    // Issuer wants to unauthorize the holder, unset lsfMPTAuthorized on
+    // their MPToken
+    if (flags & tfMPTUnauthorize)
+    {
+        flagsOut &= ~lsfMPTAuthorized;
+    }
+    // Issuer wants to authorize a holder, set lsfMPTAuthorized on their
+    // MPToken
+    else
+    {
+        flagsOut |= lsfMPTAuthorized;
+    }
+
+    if (flagsIn != flagsOut)
+        sleMpt->setFieldU32(sfFlags, flagsOut);
+
+    view.update(sleMpt);
+    return tesSUCCESS;
+}
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    MPTIssue const& mptIssue,
+    beast::Journal journal)
+{
+    // If the account is the issuer, then no token should exist. MPTs do not
+    // have the legacy ability to create such a situation, but check anyway. If
+    // a token does exist, it will get deleted. If not, return success.
+    bool const accountIsIssuer = accountID == mptIssue.getIssuer();
+    auto const& mptID = mptIssue.getMptID();
+    auto const mptoken = view.peek(keylet::mptoken(mptID, accountID));
+    if (!mptoken)
+        return accountIsIssuer ? (TER)tesSUCCESS : (TER)tecOBJECT_NOT_FOUND;
+    // Unlike a trust line, if the account is the issuer, and the token has a
+    // balance, it can not just be deleted, because that will throw the issuance
+    // accounting out of balance, so fail. Since this should be impossible
+    // anyway, I'm not going to put any effort into it.
+    if (mptoken->at(sfMPTAmount) != 0)
+        return tecHAS_OBLIGATIONS;
+
+    return authorizeMPToken(
+        view,
+        {},  // priorBalance
+        mptID,
+        accountID,
+        journal,
+        tfMPTUnauthorize  // flags
+    );
+}
+
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& account,
+    AuthType authType,
+    int depth)
+{
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto const sleIssuance = view.read(mptID);
+    if (!sleIssuance)
+        return tecOBJECT_NOT_FOUND;
+
+    auto const mptIssuer = sleIssuance->getAccountID(sfIssuer);
+
+    // issuer is always "authorized"
+    if (mptIssuer == account)  // Issuer won't have MPToken
+        return tesSUCCESS;
+
+    bool const featureSAVEnabled = view.rules().enabled(featureSingleAssetVault);
+
+    if (featureSAVEnabled)
+    {
+        if (depth >= maxAssetCheckDepth)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        // requireAuth is recursive if the issuer is a vault pseudo-account
+        auto const sleIssuer = view.read(keylet::account(mptIssuer));
+        if (!sleIssuer)
+            return tefINTERNAL;  // LCOV_EXCL_LINE
+
+        if (sleIssuer->isFieldPresent(sfVaultID))
+        {
+            auto const sleVault = view.read(keylet::vault(sleIssuer->getFieldH256(sfVaultID)));
+            if (!sleVault)
+                return tefINTERNAL;  // LCOV_EXCL_LINE
+
+            auto const asset = sleVault->at(sfAsset);
+            if (auto const err = std::visit(
+                    [&]<ValidIssueType TIss>(TIss const& issue) {
+                        if constexpr (std::is_same_v<TIss, Issue>)
+                        {
+                            return requireAuth(view, issue, account, authType);
+                        }
+                        else
+                        {
+                            return requireAuth(view, issue, account, authType, depth + 1);
+                        }
+                    },
+                    asset.value());
+                !isTesSuccess(err))
+                return err;
+        }
+    }
+
+    auto const mptokenID = keylet::mptoken(mptID.key, account);
+    auto const sleToken = view.read(mptokenID);
+
+    // if account has no MPToken, fail
+    if (!sleToken && (authType == AuthType::StrongAuth || authType == AuthType::Legacy))
+        return tecNO_AUTH;
+
+    // Note, this check is not amendment-gated because DomainID will be always
+    // empty **unless** writing to it has been enabled by an amendment
+    auto const maybeDomainID = sleIssuance->at(~sfDomainID);
+    if (maybeDomainID)
+    {
+        XRPL_ASSERT(
+            sleIssuance->getFieldU32(sfFlags) & lsfMPTRequireAuth,
+            "xrpl::requireAuth : issuance requires authorization");
+        // ter = tefINTERNAL | tecOBJECT_NOT_FOUND | tecNO_AUTH | tecEXPIRED
+        auto const ter = credentials::validDomain(view, *maybeDomainID, account);
+        if (isTesSuccess(ter))
+        {
+            return ter;  // Note: sleToken might be null
+        }
+        if (!sleToken)
+        {
+            return ter;
+        }
+        // We ignore error from validDomain if we found sleToken, as it could
+        // belong to someone who is explicitly authorized e.g. a vault owner.
+    }
+
+    if (featureSAVEnabled)
+    {
+        // Implicitly authorize Vault and LoanBroker pseudo-accounts
+        if (isPseudoAccount(view, account, {&sfVaultID, &sfLoanBrokerID}))
+            return tesSUCCESS;
+    }
+
+    // mptoken must be authorized if issuance enabled requireAuth
+    if (sleIssuance->isFlag(lsfMPTRequireAuth) &&
+        (!sleToken || !sleToken->isFlag(lsfMPTAuthorized)))
+        return tecNO_AUTH;
+
+    return tesSUCCESS;  // Note: sleToken might be null
+}
+
+[[nodiscard]] TER
+enforceMPTokenAuthorization(
+    ApplyView& view,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    XRPAmount const& priorBalance,  // for MPToken authorization
+    beast::Journal j)
+{
+    auto const sleIssuance = view.read(keylet::mptIssuance(mptIssuanceID));
+    if (!sleIssuance)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    XRPL_ASSERT(
+        sleIssuance->isFlag(lsfMPTRequireAuth),
+        "xrpl::enforceMPTokenAuthorization : authorization required");
+
+    if (account == sleIssuance->at(sfIssuer))
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const keylet = keylet::mptoken(mptIssuanceID, account);
+    auto const sleToken = view.read(keylet);  //  NOTE: might be null
+    auto const maybeDomainID = sleIssuance->at(~sfDomainID);
+    bool expired = false;
+    bool const authorizedByDomain = [&]() -> bool {
+        // NOTE: defensive here, should be checked in preclaim
+        if (!maybeDomainID.has_value())
+            return false;  // LCOV_EXCL_LINE
+
+        auto const ter = verifyValidDomain(view, account, *maybeDomainID, j);
+        if (isTesSuccess(ter))
+            return true;
+        if (ter == tecEXPIRED)
+            expired = true;
+        return false;
+    }();
+
+    if (!authorizedByDomain && sleToken == nullptr)
+    {
+        // Could not find MPToken and won't create one, could be either of:
+        //
+        // 1. Field sfDomainID not set in MPTokenIssuance or
+        // 2. Account has no matching and accepted credentials or
+        // 3. Account has all expired credentials (deleted in verifyValidDomain)
+        //
+        // Either way, return tecNO_AUTH and there is nothing else to do
+        return expired ? tecEXPIRED : tecNO_AUTH;
+    }
+    if (!authorizedByDomain && maybeDomainID.has_value())
+    {
+        // Found an MPToken but the account is not authorized and we expect
+        // it to have been authorized by the domain. This could be because the
+        // credentials used to create the MPToken have expired or been deleted.
+        return expired ? tecEXPIRED : tecNO_AUTH;
+    }
+    if (!authorizedByDomain)
+    {
+        // We found an MPToken, but sfDomainID is not set, so this is a classic
+        // MPToken which requires authorization by the token issuer.
+        XRPL_ASSERT(
+            sleToken != nullptr && !maybeDomainID.has_value(),
+            "xrpl::enforceMPTokenAuthorization : found MPToken");
+        if (sleToken->isFlag(lsfMPTAuthorized))
+            return tesSUCCESS;
+
+        return tecNO_AUTH;
+    }
+    if (authorizedByDomain && sleToken != nullptr)
+    {
+        // Found an MPToken, authorized by the domain. Ignore authorization flag
+        // lsfMPTAuthorized because it is meaningless. Return tesSUCCESS
+        XRPL_ASSERT(
+            maybeDomainID.has_value(),
+            "xrpl::enforceMPTokenAuthorization : found MPToken for domain");
+        return tesSUCCESS;
+    }
+    if (authorizedByDomain)
+    {
+        // Could not find MPToken but there should be one because we are
+        // authorized by domain. Proceed to create it, then return tesSUCCESS
+        XRPL_ASSERT(
+            maybeDomainID.has_value() && sleToken == nullptr,
+            "xrpl::enforceMPTokenAuthorization : new MPToken for domain");
+        if (auto const err = authorizeMPToken(
+                view,
+                priorBalance,   // priorBalance
+                mptIssuanceID,  // mptIssuanceID
+                account,        // account
+                j);
+            !isTesSuccess(err))
+            return err;
+
+        return tesSUCCESS;
+    }
+
+    // LCOV_EXCL_START
+    UNREACHABLE("xrpl::enforceMPTokenAuthorization : condition list is incomplete");
+    return tefINTERNAL;
+    // LCOV_EXCL_STOP
+}
+
+TER
+canTransfer(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& from,
+    AccountID const& to)
+{
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto const sleIssuance = view.read(mptID);
+    if (!sleIssuance)
+        return tecOBJECT_NOT_FOUND;
+
+    if (!(sleIssuance->getFieldU32(sfFlags) & lsfMPTCanTransfer))
+    {
+        if (from != (*sleIssuance)[sfIssuer] && to != (*sleIssuance)[sfIssuer])
+            return TER{tecNO_AUTH};
+    }
+    return tesSUCCESS;
+}
+
+TER
+rippleLockEscrowMPT(
+    ApplyView& view,
+    AccountID const& sender,
+    STAmount const& amount,
+    beast::Journal j)
+{
+    auto const mptIssue = amount.get<MPTIssue>();
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto sleIssuance = view.peek(mptID);
+    if (!sleIssuance)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleLockEscrowMPT: MPT issuance not found for "
+                        << mptIssue.getMptID();
+        return tecOBJECT_NOT_FOUND;
+    }  // LCOV_EXCL_STOP
+
+    if (amount.getIssuer() == sender)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleLockEscrowMPT: sender is the issuer, cannot lock MPTs.";
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+
+    // 1. Decrease the MPT Holder MPTAmount
+    // 2. Increase the MPT Holder EscrowedAmount
+    {
+        auto const mptokenID = keylet::mptoken(mptID.key, sender);
+        auto sle = view.peek(mptokenID);
+        if (!sle)
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: MPToken not found for " << sender;
+            return tecOBJECT_NOT_FOUND;
+        }  // LCOV_EXCL_STOP
+
+        auto const amt = sle->getFieldU64(sfMPTAmount);
+        auto const pay = amount.mpt().value();
+
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, amt), STAmount(mptIssue, pay)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: insufficient MPTAmount for "
+                            << to_string(sender) << ": " << amt << " < " << pay;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        (*sle)[sfMPTAmount] = amt - pay;
+
+        // Overflow check for addition
+        uint64_t const locked = (*sle)[~sfLockedAmount].value_or(0);
+
+        if (!canAdd(STAmount(mptIssue, locked), STAmount(mptIssue, pay)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: overflow on locked amount for "
+                            << to_string(sender) << ": " << locked << " + " << pay;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        if (sle->isFieldPresent(sfLockedAmount))
+        {
+            (*sle)[sfLockedAmount] += pay;
+        }
+        else
+        {
+            sle->setFieldU64(sfLockedAmount, pay);
+        }
+
+        view.update(sle);
+    }
+
+    // 1. Increase the Issuance EscrowedAmount
+    // 2. DO NOT change the Issuance OutstandingAmount
+    {
+        uint64_t const issuanceEscrowed = (*sleIssuance)[~sfLockedAmount].value_or(0);
+        auto const pay = amount.mpt().value();
+
+        // Overflow check for addition
+        if (!canAdd(STAmount(mptIssue, issuanceEscrowed), STAmount(mptIssue, pay)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: overflow on issuance "
+                               "locked amount for "
+                            << mptIssue.getMptID() << ": " << issuanceEscrowed << " + " << pay;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        if (sleIssuance->isFieldPresent(sfLockedAmount))
+        {
+            (*sleIssuance)[sfLockedAmount] += pay;
+        }
+        else
+        {
+            sleIssuance->setFieldU64(sfLockedAmount, pay);
+        }
+
+        view.update(sleIssuance);
+    }
+    return tesSUCCESS;
+}
+
+TER
+rippleUnlockEscrowMPT(
+    ApplyView& view,
+    AccountID const& sender,
+    AccountID const& receiver,
+    STAmount const& netAmount,
+    STAmount const& grossAmount,
+    beast::Journal j)
+{
+    if (!view.rules().enabled(fixTokenEscrowV1))
+    {
+        XRPL_ASSERT(
+            netAmount == grossAmount, "xrpl::rippleUnlockEscrowMPT : netAmount == grossAmount");
+    }
+
+    auto const& issuer = netAmount.getIssuer();
+    auto const& mptIssue = netAmount.get<MPTIssue>();
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto sleIssuance = view.peek(mptID);
+    if (!sleIssuance)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: MPT issuance not found for "
+                        << mptIssue.getMptID();
+        return tecOBJECT_NOT_FOUND;
+    }  // LCOV_EXCL_STOP
+
+    // Decrease the Issuance EscrowedAmount
+    {
+        if (!sleIssuance->isFieldPresent(sfLockedAmount))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: no locked amount in issuance for "
+                            << mptIssue.getMptID();
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        auto const locked = sleIssuance->getFieldU64(sfLockedAmount);
+        auto const redeem = grossAmount.mpt().value();
+
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, locked), STAmount(mptIssue, redeem)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient locked amount for "
+                            << mptIssue.getMptID() << ": " << locked << " < " << redeem;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        auto const newLocked = locked - redeem;
+        if (newLocked == 0)
+        {
+            sleIssuance->makeFieldAbsent(sfLockedAmount);
+        }
+        else
+        {
+            sleIssuance->setFieldU64(sfLockedAmount, newLocked);
+        }
+        view.update(sleIssuance);
+    }
+
+    if (issuer != receiver)
+    {
+        // Increase the MPT Holder MPTAmount
+        auto const mptokenID = keylet::mptoken(mptID.key, receiver);
+        auto sle = view.peek(mptokenID);
+        if (!sle)
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: MPToken not found for " << receiver;
+            return tecOBJECT_NOT_FOUND;
+        }  // LCOV_EXCL_STOP
+
+        auto current = sle->getFieldU64(sfMPTAmount);
+        auto delta = netAmount.mpt().value();
+
+        // Overflow check for addition
+        if (!canAdd(STAmount(mptIssue, current), STAmount(mptIssue, delta)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: overflow on MPTAmount for "
+                            << to_string(receiver) << ": " << current << " + " << delta;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        (*sle)[sfMPTAmount] += delta;
+        view.update(sle);
+    }
+    else
+    {
+        // Decrease the Issuance OutstandingAmount
+        auto const outstanding = sleIssuance->getFieldU64(sfOutstandingAmount);
+        auto const redeem = netAmount.mpt().value();
+
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, outstanding), STAmount(mptIssue, redeem)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient outstanding amount for "
+                            << mptIssue.getMptID() << ": " << outstanding << " < " << redeem;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        sleIssuance->setFieldU64(sfOutstandingAmount, outstanding - redeem);
+        view.update(sleIssuance);
+    }
+
+    if (issuer == sender)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: sender is the issuer, "
+                           "cannot unlock MPTs.";
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+    // Decrease the MPT Holder EscrowedAmount
+    auto const mptokenID = keylet::mptoken(mptID.key, sender);
+    auto sle = view.peek(mptokenID);
+    if (!sle)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: MPToken not found for " << sender;
+        return tecOBJECT_NOT_FOUND;
+    }  // LCOV_EXCL_STOP
+
+    if (!sle->isFieldPresent(sfLockedAmount))
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: no locked amount in MPToken for "
+                        << to_string(sender);
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+
+    auto const locked = sle->getFieldU64(sfLockedAmount);
+    auto const delta = grossAmount.mpt().value();
+
+    // Underflow check for subtraction
+    if (!canSubtract(STAmount(mptIssue, locked), STAmount(mptIssue, delta)))
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient locked amount for "
+                        << to_string(sender) << ": " << locked << " < " << delta;
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+
+    auto const newLocked = locked - delta;
+    if (newLocked == 0)
+    {
+        sle->makeFieldAbsent(sfLockedAmount);
+    }
+    else
+    {
+        sle->setFieldU64(sfLockedAmount, newLocked);
+    }
+    view.update(sle);
+
+    // Note: The gross amount is the amount that was locked, the net
+    // amount is the amount that is being unlocked. The difference is the fee
+    // that was charged for the transfer. If this difference is greater than
+    // zero, we need to update the outstanding amount.
+    auto const diff = grossAmount.mpt().value() - netAmount.mpt().value();
+    if (diff != 0)
+    {
+        auto const outstanding = sleIssuance->getFieldU64(sfOutstandingAmount);
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, outstanding), STAmount(mptIssue, diff)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient outstanding amount for "
+                            << mptIssue.getMptID() << ": " << outstanding << " < " << diff;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        sleIssuance->setFieldU64(sfOutstandingAmount, outstanding - diff);
+        view.update(sleIssuance);
+    }
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/OfferHelpers.cpp

@@ -0,0 +1,58 @@
+#include <xrpl/ledger/helpers/OfferHelpers.h>
+//
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/st.h>
+
+namespace xrpl {
+
+TER
+offerDelete(ApplyView& view, std::shared_ptr<SLE> const& sle, beast::Journal j)
+{
+    if (!sle)
+        return tesSUCCESS;
+    auto offerIndex = sle->key();
+    auto owner = sle->getAccountID(sfAccount);
+
+    // Detect legacy directories.
+    uint256 uDirectory = sle->getFieldH256(sfBookDirectory);
+
+    if (!view.dirRemove(keylet::ownerDir(owner), sle->getFieldU64(sfOwnerNode), offerIndex, false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    if (!view.dirRemove(keylet::page(uDirectory), sle->getFieldU64(sfBookNode), offerIndex, false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    if (sle->isFieldPresent(sfAdditionalBooks))
+    {
+        XRPL_ASSERT(
+            sle->isFlag(lsfHybrid) && sle->isFieldPresent(sfDomainID),
+            "xrpl::offerDelete : should be a hybrid domain offer");
+
+        auto const& additionalBookDirs = sle->getFieldArray(sfAdditionalBooks);
+
+        for (auto const& bookDir : additionalBookDirs)
+        {
+            auto const& dirIndex = bookDir.getFieldH256(sfBookDirectory);
+            auto const& dirNode = bookDir.getFieldU64(sfBookNode);
+
+            if (!view.dirRemove(keylet::page(dirIndex), dirNode, offerIndex, false))
+            {
+                return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+            }
+        }
+    }
+
+    adjustOwnerCount(view, view.peek(keylet::account(owner)), -1, j);
+
+    view.erase(sle);
+
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/RippleStateHelpers.cpp

@@ -0,0 +1,759 @@
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
+//
+#include <xrpl/basics/Log.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/protocol/AmountConversions.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/Rules.h>
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Credit functions (from Credit.cpp)
+//
+//------------------------------------------------------------------------------
+
+STAmount
+creditLimit(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency)
+{
+    STAmount result(Issue{currency, account});
+
+    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
+
+    if (sleRippleState)
+    {
+        result = sleRippleState->getFieldAmount(account < issuer ? sfLowLimit : sfHighLimit);
+        result.setIssuer(account);
+    }
+
+    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditLimit : result issuer match");
+    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditLimit : result currency match");
+    return result;
+}
+
+IOUAmount
+creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur)
+{
+    return toAmount<IOUAmount>(creditLimit(v, acc, iss, cur));
+}
+
+STAmount
+creditBalance(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency)
+{
+    STAmount result(Issue{currency, account});
+
+    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
+
+    if (sleRippleState)
+    {
+        result = sleRippleState->getFieldAmount(sfBalance);
+        if (account < issuer)
+            result.negate();
+        result.setIssuer(account);
+    }
+
+    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditBalance : result issuer match");
+    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditBalance : result currency match");
+    return result;
+}
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+bool
+isIndividualFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer)
+{
+    if (isXRP(currency))
+        return false;
+    if (issuer != account)
+    {
+        // Check if the issuer froze the line
+        auto const sle = view.read(keylet::line(account, issuer, currency));
+        if (sle && sle->isFlag((issuer > account) ? lsfHighFreeze : lsfLowFreeze))
+            return true;
+    }
+    return false;
+}
+
+// Can the specified account spend the specified currency issued by
+// the specified issuer or does the freeze flag prohibit it?
+bool
+isFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer)
+{
+    if (isXRP(currency))
+        return false;
+    auto sle = view.read(keylet::account(issuer));
+    if (sle && sle->isFlag(lsfGlobalFreeze))
+        return true;
+    if (issuer != account)
+    {
+        // Check if the issuer froze the line
+        sle = view.read(keylet::line(account, issuer, currency));
+        if (sle && sle->isFlag((issuer > account) ? lsfHighFreeze : lsfLowFreeze))
+            return true;
+    }
+    return false;
+}
+
+bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer)
+{
+    if (isXRP(currency))
+    {
+        return false;
+    }
+
+    if (issuer == account)
+    {
+        return false;
+    }
+
+    auto const sle = view.read(keylet::line(account, issuer, currency));
+    if (!sle)
+    {
+        return false;
+    }
+
+    return sle->isFlag(lsfHighDeepFreeze) || sle->isFlag(lsfLowDeepFreeze);
+}
+
+//------------------------------------------------------------------------------
+//
+// Trust line operations
+//
+//------------------------------------------------------------------------------
+
+TER
+trustCreate(
+    ApplyView& view,
+    bool const bSrcHigh,
+    AccountID const& uSrcAccountID,
+    AccountID const& uDstAccountID,
+    uint256 const& uIndex,      // --> ripple state entry
+    SLE::ref sleAccount,        // --> the account being set.
+    bool const bAuth,           // --> authorize account.
+    bool const bNoRipple,       // --> others cannot ripple through
+    bool const bFreeze,         // --> funds cannot leave
+    bool bDeepFreeze,           // --> can neither receive nor send funds
+    STAmount const& saBalance,  // --> balance of account being set.
+                                // Issuer should be noAccount()
+    STAmount const& saLimit,    // --> limit for account being set.
+                                // Issuer should be the account being set.
+    std::uint32_t uQualityIn,
+    std::uint32_t uQualityOut,
+    beast::Journal j)
+{
+    JLOG(j.trace()) << "trustCreate: " << to_string(uSrcAccountID) << ", "
+                    << to_string(uDstAccountID) << ", " << saBalance.getFullText();
+
+    auto const& uLowAccountID = !bSrcHigh ? uSrcAccountID : uDstAccountID;
+    auto const& uHighAccountID = bSrcHigh ? uSrcAccountID : uDstAccountID;
+    if (uLowAccountID == uHighAccountID)
+    {
+        // LCOV_EXCL_START
+        UNREACHABLE("xrpl::trustCreate : trust line to self");
+        if (view.rules().enabled(featureLendingProtocol))
+            return tecINTERNAL;
+        // LCOV_EXCL_STOP
+    }
+
+    auto const sleRippleState = std::make_shared<SLE>(ltRIPPLE_STATE, uIndex);
+    view.insert(sleRippleState);
+
+    auto lowNode = view.dirInsert(
+        keylet::ownerDir(uLowAccountID), sleRippleState->key(), describeOwnerDir(uLowAccountID));
+
+    if (!lowNode)
+        return tecDIR_FULL;  // LCOV_EXCL_LINE
+
+    auto highNode = view.dirInsert(
+        keylet::ownerDir(uHighAccountID), sleRippleState->key(), describeOwnerDir(uHighAccountID));
+
+    if (!highNode)
+        return tecDIR_FULL;  // LCOV_EXCL_LINE
+
+    bool const bSetDst = saLimit.getIssuer() == uDstAccountID;
+    bool const bSetHigh = bSrcHigh ^ bSetDst;
+
+    XRPL_ASSERT(sleAccount, "xrpl::trustCreate : non-null SLE");
+    if (!sleAccount)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    XRPL_ASSERT(
+        sleAccount->getAccountID(sfAccount) == (bSetHigh ? uHighAccountID : uLowAccountID),
+        "xrpl::trustCreate : matching account ID");
+    auto const slePeer = view.peek(keylet::account(bSetHigh ? uLowAccountID : uHighAccountID));
+    if (!slePeer)
+        return tecNO_TARGET;
+
+    // Remember deletion hints.
+    sleRippleState->setFieldU64(sfLowNode, *lowNode);
+    sleRippleState->setFieldU64(sfHighNode, *highNode);
+
+    sleRippleState->setFieldAmount(bSetHigh ? sfHighLimit : sfLowLimit, saLimit);
+    sleRippleState->setFieldAmount(
+        bSetHigh ? sfLowLimit : sfHighLimit,
+        STAmount(Issue{saBalance.getCurrency(), bSetDst ? uSrcAccountID : uDstAccountID}));
+
+    if (uQualityIn)
+        sleRippleState->setFieldU32(bSetHigh ? sfHighQualityIn : sfLowQualityIn, uQualityIn);
+
+    if (uQualityOut)
+        sleRippleState->setFieldU32(bSetHigh ? sfHighQualityOut : sfLowQualityOut, uQualityOut);
+
+    std::uint32_t uFlags = bSetHigh ? lsfHighReserve : lsfLowReserve;
+
+    if (bAuth)
+    {
+        uFlags |= (bSetHigh ? lsfHighAuth : lsfLowAuth);
+    }
+    if (bNoRipple)
+    {
+        uFlags |= (bSetHigh ? lsfHighNoRipple : lsfLowNoRipple);
+    }
+    if (bFreeze)
+    {
+        uFlags |= (bSetHigh ? lsfHighFreeze : lsfLowFreeze);
+    }
+    if (bDeepFreeze)
+    {
+        uFlags |= (bSetHigh ? lsfHighDeepFreeze : lsfLowDeepFreeze);
+    }
+
+    if ((slePeer->getFlags() & lsfDefaultRipple) == 0)
+    {
+        // The other side's default is no rippling
+        uFlags |= (bSetHigh ? lsfLowNoRipple : lsfHighNoRipple);
+    }
+
+    sleRippleState->setFieldU32(sfFlags, uFlags);
+    adjustOwnerCount(view, sleAccount, 1, j);
+
+    // ONLY: Create ripple balance.
+    sleRippleState->setFieldAmount(sfBalance, bSetHigh ? -saBalance : saBalance);
+
+    view.creditHook(uSrcAccountID, uDstAccountID, saBalance, saBalance.zeroed());
+
+    return tesSUCCESS;
+}
+
+TER
+trustDelete(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sleRippleState,
+    AccountID const& uLowAccountID,
+    AccountID const& uHighAccountID,
+    beast::Journal j)
+{
+    // Detect legacy dirs.
+    std::uint64_t uLowNode = sleRippleState->getFieldU64(sfLowNode);
+    std::uint64_t uHighNode = sleRippleState->getFieldU64(sfHighNode);
+
+    JLOG(j.trace()) << "trustDelete: Deleting ripple line: low";
+
+    if (!view.dirRemove(keylet::ownerDir(uLowAccountID), uLowNode, sleRippleState->key(), false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    JLOG(j.trace()) << "trustDelete: Deleting ripple line: high";
+
+    if (!view.dirRemove(keylet::ownerDir(uHighAccountID), uHighNode, sleRippleState->key(), false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    JLOG(j.trace()) << "trustDelete: Deleting ripple line: state";
+    view.erase(sleRippleState);
+
+    return tesSUCCESS;
+}
+
+//------------------------------------------------------------------------------
+//
+// IOU issuance/redemption
+//
+//------------------------------------------------------------------------------
+
+static bool
+updateTrustLine(
+    ApplyView& view,
+    SLE::pointer state,
+    bool bSenderHigh,
+    AccountID const& sender,
+    STAmount const& before,
+    STAmount const& after,
+    beast::Journal j)
+{
+    if (!state)
+        return false;
+    std::uint32_t const flags(state->getFieldU32(sfFlags));
+
+    auto sle = view.peek(keylet::account(sender));
+    if (!sle)
+        return false;
+
+    // YYY Could skip this if rippling in reverse.
+    if (before > beast::zero
+        // Sender balance was positive.
+        && after <= beast::zero
+        // Sender is zero or negative.
+        && (flags & (!bSenderHigh ? lsfLowReserve : lsfHighReserve))
+        // Sender reserve is set.
+        && static_cast<bool>(flags & (!bSenderHigh ? lsfLowNoRipple : lsfHighNoRipple)) !=
+            static_cast<bool>(sle->getFlags() & lsfDefaultRipple) &&
+        !(flags & (!bSenderHigh ? lsfLowFreeze : lsfHighFreeze)) &&
+        !state->getFieldAmount(!bSenderHigh ? sfLowLimit : sfHighLimit)
+        // Sender trust limit is 0.
+        && !state->getFieldU32(!bSenderHigh ? sfLowQualityIn : sfHighQualityIn)
+        // Sender quality in is 0.
+        && !state->getFieldU32(!bSenderHigh ? sfLowQualityOut : sfHighQualityOut))
+    // Sender quality out is 0.
+    {
+        // VFALCO Where is the line being deleted?
+        // Clear the reserve of the sender, possibly delete the line!
+        adjustOwnerCount(view, sle, -1, j);
+
+        // Clear reserve flag.
+        state->setFieldU32(sfFlags, flags & (!bSenderHigh ? ~lsfLowReserve : ~lsfHighReserve));
+
+        // Balance is zero, receiver reserve is clear.
+        if (!after  // Balance is zero.
+            && !(flags & (bSenderHigh ? lsfLowReserve : lsfHighReserve)))
+            return true;
+    }
+    return false;
+}
+
+TER
+issueIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j)
+{
+    XRPL_ASSERT(
+        !isXRP(account) && !isXRP(issue.account),
+        "xrpl::issueIOU : neither account nor issuer is XRP");
+
+    // Consistency check
+    XRPL_ASSERT(issue == amount.issue(), "xrpl::issueIOU : matching issue");
+
+    // Can't send to self!
+    XRPL_ASSERT(issue.account != account, "xrpl::issueIOU : not issuer account");
+
+    JLOG(j.trace()) << "issueIOU: " << to_string(account) << ": " << amount.getFullText();
+
+    bool bSenderHigh = issue.account > account;
+
+    auto const index = keylet::line(issue.account, account, issue.currency);
+
+    if (auto state = view.peek(index))
+    {
+        STAmount final_balance = state->getFieldAmount(sfBalance);
+
+        if (bSenderHigh)
+            final_balance.negate();  // Put balance in sender terms.
+
+        STAmount const start_balance = final_balance;
+
+        final_balance -= amount;
+
+        auto const must_delete = updateTrustLine(
+            view, state, bSenderHigh, issue.account, start_balance, final_balance, j);
+
+        view.creditHook(issue.account, account, amount, start_balance);
+
+        if (bSenderHigh)
+            final_balance.negate();
+
+        // Adjust the balance on the trust line if necessary. We do this even
+        // if we are going to delete the line to reflect the correct balance
+        // at the time of deletion.
+        state->setFieldAmount(sfBalance, final_balance);
+        if (must_delete)
+        {
+            return trustDelete(
+                view,
+                state,
+                bSenderHigh ? account : issue.account,
+                bSenderHigh ? issue.account : account,
+                j);
+        }
+
+        view.update(state);
+
+        return tesSUCCESS;
+    }
+
+    // NIKB TODO: The limit uses the receiver's account as the issuer and
+    // this is unnecessarily inefficient as copying which could be avoided
+    // is now required. Consider available options.
+    STAmount const limit(Issue{issue.currency, account});
+    STAmount final_balance = amount;
+
+    final_balance.setIssuer(noAccount());
+
+    auto const receiverAccount = view.peek(keylet::account(account));
+    if (!receiverAccount)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    bool noRipple = (receiverAccount->getFlags() & lsfDefaultRipple) == 0;
+
+    return trustCreate(
+        view,
+        bSenderHigh,
+        issue.account,
+        account,
+        index.key,
+        receiverAccount,
+        false,
+        noRipple,
+        false,
+        false,
+        final_balance,
+        limit,
+        0,
+        0,
+        j);
+}
+
+TER
+redeemIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j)
+{
+    XRPL_ASSERT(
+        !isXRP(account) && !isXRP(issue.account),
+        "xrpl::redeemIOU : neither account nor issuer is XRP");
+
+    // Consistency check
+    XRPL_ASSERT(issue == amount.issue(), "xrpl::redeemIOU : matching issue");
+
+    // Can't send to self!
+    XRPL_ASSERT(issue.account != account, "xrpl::redeemIOU : not issuer account");
+
+    JLOG(j.trace()) << "redeemIOU: " << to_string(account) << ": " << amount.getFullText();
+
+    bool bSenderHigh = account > issue.account;
+
+    if (auto state = view.peek(keylet::line(account, issue.account, issue.currency)))
+    {
+        STAmount final_balance = state->getFieldAmount(sfBalance);
+
+        if (bSenderHigh)
+            final_balance.negate();  // Put balance in sender terms.
+
+        STAmount const start_balance = final_balance;
+
+        final_balance -= amount;
+
+        auto const must_delete =
+            updateTrustLine(view, state, bSenderHigh, account, start_balance, final_balance, j);
+
+        view.creditHook(account, issue.account, amount, start_balance);
+
+        if (bSenderHigh)
+            final_balance.negate();
+
+        // Adjust the balance on the trust line if necessary. We do this even
+        // if we are going to delete the line to reflect the correct balance
+        // at the time of deletion.
+        state->setFieldAmount(sfBalance, final_balance);
+
+        if (must_delete)
+        {
+            return trustDelete(
+                view,
+                state,
+                bSenderHigh ? issue.account : account,
+                bSenderHigh ? account : issue.account,
+                j);
+        }
+
+        view.update(state);
+        return tesSUCCESS;
+    }
+
+    // In order to hold an IOU, a trust line *MUST* exist to track the
+    // balance. If it doesn't, then something is very wrong. Don't try
+    // to continue.
+    // LCOV_EXCL_START
+    JLOG(j.fatal()) << "redeemIOU: " << to_string(account) << " attempts to "
+                    << "redeem " << amount.getFullText() << " but no trust line exists!";
+
+    return tefINTERNAL;
+    // LCOV_EXCL_STOP
+}
+
+//------------------------------------------------------------------------------
+//
+// Authorization and transfer checks (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+TER
+requireAuth(ReadView const& view, Issue const& issue, AccountID const& account, AuthType authType)
+{
+    if (isXRP(issue) || issue.account == account)
+        return tesSUCCESS;
+
+    auto const trustLine = view.read(keylet::line(account, issue.account, issue.currency));
+    // If account has no line, and this is a strong check, fail
+    if (!trustLine && authType == AuthType::StrongAuth)
+        return tecNO_LINE;
+
+    // If this is a weak or legacy check, or if the account has a line, fail if
+    // auth is required and not set on the line
+    if (auto const issuerAccount = view.read(keylet::account(issue.account));
+        issuerAccount && (*issuerAccount)[sfFlags] & lsfRequireAuth)
+    {
+        if (trustLine)
+        {
+            return ((*trustLine)[sfFlags] & ((account > issue.account) ? lsfLowAuth : lsfHighAuth))
+                ? tesSUCCESS
+                : TER{tecNO_AUTH};
+        }
+        return TER{tecNO_LINE};
+    }
+
+    return tesSUCCESS;
+}
+
+TER
+canTransfer(ReadView const& view, Issue const& issue, AccountID const& from, AccountID const& to)
+{
+    if (issue.native())
+        return tesSUCCESS;
+
+    auto const& issuerId = issue.getIssuer();
+    if (issuerId == from || issuerId == to)
+        return tesSUCCESS;
+    auto const sleIssuer = view.read(keylet::account(issuerId));
+    if (sleIssuer == nullptr)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const isRippleDisabled = [&](AccountID account) -> bool {
+        // Line might not exist, but some transfers can create it. If this
+        // is the case, just check the default ripple on the issuer account.
+        auto const line = view.read(keylet::line(account, issue));
+        if (line)
+        {
+            bool const issuerHigh = issuerId > account;
+            return line->isFlag(issuerHigh ? lsfHighNoRipple : lsfLowNoRipple);
+        }
+        return sleIssuer->isFlag(lsfDefaultRipple) == false;
+    };
+
+    // Fail if rippling disabled on both trust lines
+    if (isRippleDisabled(from) && isRippleDisabled(to))
+        return terNO_RIPPLE;
+
+    return tesSUCCESS;
+}
+
+//------------------------------------------------------------------------------
+//
+// Empty holding operations (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    Issue const& issue,
+    beast::Journal journal)
+{
+    // Every account can hold XRP. An issuer can issue directly.
+    if (issue.native() || accountID == issue.getIssuer())
+        return tesSUCCESS;
+
+    auto const& issuerId = issue.getIssuer();
+    auto const& currency = issue.currency;
+    if (isGlobalFrozen(view, issuerId))
+        return tecFROZEN;  // LCOV_EXCL_LINE
+
+    auto const& srcId = issuerId;
+    auto const& dstId = accountID;
+    auto const high = srcId > dstId;
+    auto const index = keylet::line(srcId, dstId, currency);
+    auto const sleSrc = view.peek(keylet::account(srcId));
+    auto const sleDst = view.peek(keylet::account(dstId));
+    if (!sleDst || !sleSrc)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+    if (!sleSrc->isFlag(lsfDefaultRipple))
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+    // If the line already exists, don't create it again.
+    if (view.read(index))
+        return tecDUPLICATE;
+
+    // Can the account cover the trust line reserve ?
+    std::uint32_t const ownerCount = sleDst->at(sfOwnerCount);
+    if (priorBalance < view.fees().accountReserve(ownerCount + 1))
+        return tecNO_LINE_INSUF_RESERVE;
+
+    return trustCreate(
+        view,
+        high,
+        srcId,
+        dstId,
+        index.key,
+        sleDst,
+        /*bAuth=*/false,
+        /*bNoRipple=*/true,
+        /*bFreeze=*/false,
+        /*deepFreeze*/ false,
+        /*saBalance=*/STAmount{Issue{currency, noAccount()}},
+        /*saLimit=*/STAmount{Issue{currency, dstId}},
+        /*uQualityIn=*/0,
+        /*uQualityOut=*/0,
+        journal);
+}
+
+TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    Issue const& issue,
+    beast::Journal journal)
+{
+    if (issue.native())
+    {
+        auto const sle = view.read(keylet::account(accountID));
+        if (!sle)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        auto const balance = sle->getFieldAmount(sfBalance);
+        if (balance.xrp() != 0)
+            return tecHAS_OBLIGATIONS;
+
+        return tesSUCCESS;
+    }
+
+    // `asset` is an IOU.
+    // If the account is the issuer, then no line should exist. Check anyway.
+    // If a line does exist, it will get deleted. If not, return success.
+    bool const accountIsIssuer = accountID == issue.account;
+    auto const line = view.peek(keylet::line(accountID, issue));
+    if (!line)
+        return accountIsIssuer ? (TER)tesSUCCESS : (TER)tecOBJECT_NOT_FOUND;
+    if (!accountIsIssuer && line->at(sfBalance)->iou() != beast::zero)
+        return tecHAS_OBLIGATIONS;
+
+    // Adjust the owner count(s)
+    if (line->isFlag(lsfLowReserve))
+    {
+        // Clear reserve for low account.
+        auto sleLowAccount = view.peek(keylet::account(line->at(sfLowLimit)->getIssuer()));
+        if (!sleLowAccount)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        adjustOwnerCount(view, sleLowAccount, -1, journal);
+        // It's not really necessary to clear the reserve flag, since the line
+        // is about to be deleted, but this will make the metadata reflect an
+        // accurate state at the time of deletion.
+        line->clearFlag(lsfLowReserve);
+    }
+
+    if (line->isFlag(lsfHighReserve))
+    {
+        // Clear reserve for high account.
+        auto sleHighAccount = view.peek(keylet::account(line->at(sfHighLimit)->getIssuer()));
+        if (!sleHighAccount)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        adjustOwnerCount(view, sleHighAccount, -1, journal);
+        // It's not really necessary to clear the reserve flag, since the line
+        // is about to be deleted, but this will make the metadata reflect an
+        // accurate state at the time of deletion.
+        line->clearFlag(lsfHighReserve);
+    }
+
+    return trustDelete(
+        view, line, line->at(sfLowLimit)->getIssuer(), line->at(sfHighLimit)->getIssuer(), journal);
+}
+
+TER
+deleteAMMTrustLine(
+    ApplyView& view,
+    std::shared_ptr<SLE> sleState,
+    std::optional<AccountID> const& ammAccountID,
+    beast::Journal j)
+{
+    if (!sleState || sleState->getType() != ltRIPPLE_STATE)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const& [low, high] = std::minmax(
+        sleState->getFieldAmount(sfLowLimit).getIssuer(),
+        sleState->getFieldAmount(sfHighLimit).getIssuer());
+    auto sleLow = view.peek(keylet::account(low));
+    auto sleHigh = view.peek(keylet::account(high));
+    if (!sleLow || !sleHigh)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    bool const ammLow = sleLow->isFieldPresent(sfAMMID);
+    bool const ammHigh = sleHigh->isFieldPresent(sfAMMID);
+
+    // can't both be AMM
+    if (ammLow && ammHigh)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    // at least one must be
+    if (!ammLow && !ammHigh)
+        return terNO_AMM;
+
+    // one must be the target amm
+    if (ammAccountID && (low != *ammAccountID && high != *ammAccountID))
+        return terNO_AMM;
+
+    if (auto const ter = trustDelete(view, sleState, low, high, j); !isTesSuccess(ter))
+    {
+        JLOG(j.error()) << "deleteAMMTrustLine: failed to delete the trustline.";
+        return ter;
+    }
+
+    auto const uFlags = !ammLow ? lsfLowReserve : lsfHighReserve;
+    if (!(sleState->getFlags() & uFlags))
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    adjustOwnerCount(view, !ammLow ? sleLow : sleHigh, -1, j);
+
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/VaultHelpers.cpp

@@ -0,0 +1,112 @@
+#include <xrpl/ledger/helpers/VaultHelpers.h>
+//
+#include <xrpl/basics/Number.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/st.h>
+
+namespace xrpl {
+
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets)
+{
+    XRPL_ASSERT(!assets.negative(), "xrpl::assetsToSharesDeposit : non-negative assets");
+    XRPL_ASSERT(
+        assets.asset() == vault->at(sfAsset),
+        "xrpl::assetsToSharesDeposit : assets and vault match");
+    if (assets.negative() || assets.asset() != vault->at(sfAsset))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number const assetTotal = vault->at(sfAssetsTotal);
+    STAmount shares{vault->at(sfShareMPTID)};
+    if (assetTotal == 0)
+    {
+        return STAmount{
+            shares.asset(),
+            Number(assets.mantissa(), assets.exponent() + vault->at(sfScale)).truncate()};
+    }
+
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    shares = ((shareTotal * assets) / assetTotal).truncate();
+    return shares;
+}
+
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares)
+{
+    XRPL_ASSERT(!shares.negative(), "xrpl::sharesToAssetsDeposit : non-negative shares");
+    XRPL_ASSERT(
+        shares.asset() == vault->at(sfShareMPTID),
+        "xrpl::sharesToAssetsDeposit : shares and vault match");
+    if (shares.negative() || shares.asset() != vault->at(sfShareMPTID))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number const assetTotal = vault->at(sfAssetsTotal);
+    STAmount assets{vault->at(sfAsset)};
+    if (assetTotal == 0)
+    {
+        return STAmount{
+            assets.asset(), shares.mantissa(), shares.exponent() - vault->at(sfScale), false};
+    }
+
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    assets = (assetTotal * shares) / shareTotal;
+    return assets;
+}
+
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets,
+    TruncateShares truncate)
+{
+    XRPL_ASSERT(!assets.negative(), "xrpl::assetsToSharesWithdraw : non-negative assets");
+    XRPL_ASSERT(
+        assets.asset() == vault->at(sfAsset),
+        "xrpl::assetsToSharesWithdraw : assets and vault match");
+    if (assets.negative() || assets.asset() != vault->at(sfAsset))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number assetTotal = vault->at(sfAssetsTotal);
+    assetTotal -= vault->at(sfLossUnrealized);
+    STAmount shares{vault->at(sfShareMPTID)};
+    if (assetTotal == 0)
+        return shares;
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    Number result = (shareTotal * assets) / assetTotal;
+    if (truncate == TruncateShares::yes)
+        result = result.truncate();
+    shares = result;
+    return shares;
+}
+
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares)
+{
+    XRPL_ASSERT(!shares.negative(), "xrpl::sharesToAssetsDeposit : non-negative shares");
+    XRPL_ASSERT(
+        shares.asset() == vault->at(sfShareMPTID),
+        "xrpl::sharesToAssetsWithdraw : shares and vault match");
+    if (shares.negative() || shares.asset() != vault->at(sfShareMPTID))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number assetTotal = vault->at(sfAssetsTotal);
+    assetTotal -= vault->at(sfLossUnrealized);
+    STAmount assets{vault->at(sfAsset)};
+    if (assetTotal == 0)
+        return assets;
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    assets = (assetTotal * shares) / shareTotal;
+    return assets;
+}
+
+}  // namespace xrpl

src/libxrpl/protocol/STValidation.cpp

@@ -58,6 +58,10 @@ STValidation::validationFormat()
         {sfBaseFeeDrops,          soeOPTIONAL},
         {sfReserveBaseDrops,      soeOPTIONAL},
         {sfReserveIncrementDrops, soeOPTIONAL},
+        // featureSmartEscrow
+        {sfExtensionComputeLimit,  soeOPTIONAL},
+        {sfExtensionSizeLimit,     soeOPTIONAL},
+        {sfGasPrice,               soeOPTIONAL},
     };
     // clang-format on
 

src/libxrpl/protocol/TER.cpp

@@ -106,6 +106,7 @@ transResults()
         MAKE_ERROR(tecLIMIT_EXCEEDED,                "Limit exceeded."),
         MAKE_ERROR(tecPSEUDO_ACCOUNT,                "This operation is not allowed against a pseudo-account."),
         MAKE_ERROR(tecPRECISION_LOSS,                "The amounts used by the transaction cannot interact."),
+        MAKE_ERROR(tecWASM_REJECTED,                 "The custom WASM code that was run rejected your transaction."),
 
         MAKE_ERROR(tefALREADY,                     "The exact transaction was already in this ledger."),
         MAKE_ERROR(tefBAD_ADD_AUTH,                "Not authorized to add account."),
@@ -129,6 +130,8 @@ transResults()
         MAKE_ERROR(tefNO_TICKET,                   "Ticket is not in ledger."),
         MAKE_ERROR(tefNFTOKEN_IS_NOT_TRANSFERABLE, "The specified NFToken is not transferable."),
         MAKE_ERROR(tefINVALID_LEDGER_FIX_TYPE,     "The LedgerFixType field has an invalid value."),
+        MAKE_ERROR(tefNO_WASM,                     "There is no WASM code to run, but a WASM-specific field was included."),
+        MAKE_ERROR(tefWASM_FIELD_NOT_INCLUDED,     "WASM code requires a field to be included that was not included."),
 
         MAKE_ERROR(telLOCAL_ERROR,            "Local failure."),
         MAKE_ERROR(telBAD_DOMAIN,             "Domain too long."),
@@ -198,6 +201,8 @@ transResults()
         MAKE_ERROR(temARRAY_TOO_LARGE,           "Malformed: Array is too large."),
         MAKE_ERROR(temBAD_TRANSFER_FEE,          "Malformed: Transfer fee is outside valid range."),
         MAKE_ERROR(temINVALID_INNER_BATCH,       "Malformed: Invalid inner batch transaction."),
+        MAKE_ERROR(temBAD_WASM,                  "Malformed: Provided WASM code is invalid."),
+        MAKE_ERROR(temTEMP_DISABLED,             "The transaction requires logic that is currently temporarily disabled."),
 
         MAKE_ERROR(terRETRY,                  "Retry transaction."),
         MAKE_ERROR(terFUNDS_SPENT,            "DEPRECATED."),

src/libxrpl/protocol/TxMeta.cpp

@@ -192,6 +192,12 @@ TxMeta::getAsObject() const
     if (parentBatchID_.has_value())
         metaData.setFieldH256(sfParentBatchID, *parentBatchID_);
 
+    if (gasUsed_.has_value())
+        metaData.setFieldU32(sfGasUsed, *gasUsed_);
+
+    if (wasmReturnCode_.has_value())
+        metaData.setFieldI32(sfWasmReturnCode, *wasmReturnCode_);
+
     return metaData;
 }
 

src/libxrpl/tx/ApplyContext.cpp

@@ -40,6 +40,11 @@ ApplyContext::discard()
 std::optional<TxMeta>
 ApplyContext::apply(TER ter)
 {
+    if (wasmReturnCode_.has_value())
+    {
+        view_->setWasmReturnCode(*wasmReturnCode_);
+    }
+    view_->setGasUsed(gasUsed_);
     return view_->apply(base_, tx, ter, parentBatchId_, flags_ & tapDRY_RUN, journal);
 }
 

src/libxrpl/tx/Transactor.cpp

@@ -2,8 +2,11 @@
 #include <xrpl/basics/contract.h>
 #include <xrpl/core/NetworkIDService.h>
 #include <xrpl/json/to_string.h>
-#include <xrpl/ledger/CredentialHelpers.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Protocol.h>
@@ -975,6 +978,22 @@ removeExpiredCredentials(ApplyView& view, std::vector<uint256> const& creds, bea
     }
 }
 
+static void
+modifyWasmDataFields(
+    ApplyView& view,
+    std::vector<std::pair<uint256, Blob>> const& wasmObjects,
+    beast::Journal viewJ)
+{
+    for (auto const& [index, data] : wasmObjects)
+    {
+        if (auto const sle = view.peek(keylet::escrow(index)))
+        {
+            sle->setFieldVL(sfData, data);
+            view.update(sle);
+        }
+    }
+}
+
 static void
 removeDeletedTrustLines(
     ApplyView& view,
@@ -1125,7 +1144,8 @@ Transactor::operator()()
     }
     else if (
         (result == tecOVERSIZE) || (result == tecKILLED) || (result == tecINCOMPLETE) ||
-        (result == tecEXPIRED) || (isTecClaimHardFail(result, view().flags())))
+        (result == tecEXPIRED) || (result == tecWASM_REJECTED) ||
+        (isTecClaimHardFail(result, view().flags())))
     {
         JLOG(j_.trace()) << "reapplying because of " << transToken(result);
 
@@ -1137,12 +1157,14 @@ Transactor::operator()()
         std::vector<uint256> removedTrustLines;
         std::vector<uint256> expiredNFTokenOffers;
         std::vector<uint256> expiredCredentials;
+        std::vector<std::pair<uint256, Blob>> modifiedWasmObjects;
 
         bool const doOffers = ((result == tecOVERSIZE) || (result == tecKILLED));
         bool const doLines = (result == tecINCOMPLETE);
         bool const doNFTokenOffers = (result == tecEXPIRED);
         bool const doCredentials = (result == tecEXPIRED);
-        if (doOffers || doLines || doNFTokenOffers || doCredentials)
+        bool const doWasmData = (result == tecWASM_REJECTED);
+        if (doOffers || doLines || doNFTokenOffers || doCredentials || doWasmData)
         {
             ctx_.visit([doOffers,
                         &removedOffers,
@@ -1151,7 +1173,9 @@ Transactor::operator()()
                         doNFTokenOffers,
                         &expiredNFTokenOffers,
                         doCredentials,
-                        &expiredCredentials](
+                        &expiredCredentials,
+                        doWasmData,
+                        &modifiedWasmObjects](
                            uint256 const& index,
                            bool isDelete,
                            std::shared_ptr<SLE const> const& before,
@@ -1182,6 +1206,11 @@ Transactor::operator()()
                     if (doCredentials && before && after && (before->getType() == ltCREDENTIAL))
                         expiredCredentials.push_back(index);
                 }
+
+                if (doWasmData && before && after && (before->getType() == ltESCROW))
+                {
+                    modifiedWasmObjects.push_back(std::make_pair(index, after->getFieldVL(sfData)));
+                }
             });
         }
 
@@ -1207,6 +1236,9 @@ Transactor::operator()()
         if (result == tecEXPIRED)
             removeExpiredCredentials(view(), expiredCredentials, ctx_.registry.journal("View"));
 
+        if (result == tecWASM_REJECTED)
+            modifyWasmDataFields(view(), modifiedWasmObjects, ctx_.registry.journal("View"));
+
         applied = isTecClaim(result);
     }
 

src/libxrpl/tx/invariants/InvariantCheck.cpp

@@ -3,6 +3,8 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/LedgerFormats.h>

src/libxrpl/tx/invariants/LoanInvariant.cpp

@@ -3,6 +3,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/LedgerFormats.h>
 #include <xrpl/protocol/STNumber.h>

src/libxrpl/tx/invariants/PermissionedDomainInvariant.cpp

@@ -1,7 +1,7 @@
 #include <xrpl/tx/invariants/PermissionedDomainInvariant.h>
 //
 #include <xrpl/beast/utility/instrumentation.h>
-#include <xrpl/ledger/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/STArray.h>
 #include <xrpl/protocol/TxFormats.h>

src/libxrpl/tx/invariants/VaultInvariant.cpp

@@ -3,6 +3,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/LedgerFormats.h>

src/libxrpl/tx/paths/BookTip.cpp

@@ -1,3 +1,5 @@
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
 #include <xrpl/tx/paths/BookTip.h>
 
 namespace xrpl {

src/libxrpl/tx/paths/Flow.cpp

@@ -1,5 +1,5 @@
 #include <xrpl/basics/Log.h>
-#include <xrpl/ledger/Credit.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/IOUAmount.h>
 #include <xrpl/protocol/XRPAmount.h>
 #include <xrpl/tx/paths/Flow.h>

src/libxrpl/tx/paths/OfferStream.cpp

@@ -1,5 +1,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/LedgerFormats.h>
 #include <xrpl/tx/paths/OfferStream.h>

src/libxrpl/tx/transactors/account/AccountDelete.cpp

@@ -1,7 +1,9 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/beast/utility/instrumentation.h>
-#include <xrpl/ledger/CredentialHelpers.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Protocol.h>

src/libxrpl/tx/transactors/account/AccountSet.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/PublicKey.h>

src/libxrpl/tx/transactors/account/SignerListSet.cpp

@@ -1,6 +1,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/STArray.h>

src/libxrpl/tx/transactors/bridge/XChainBridge.cpp

@@ -5,7 +5,8 @@
 #include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/PaymentSandbox.h>
-#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>

src/libxrpl/tx/transactors/check/CheckCancel.cpp

@@ -1,6 +1,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TER.h>

src/libxrpl/tx/transactors/check/CheckCash.cpp

@@ -1,6 +1,8 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/scope.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TER.h>

src/libxrpl/tx/transactors/check/CheckCreate.cpp

@@ -1,5 +1,8 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TER.h>

src/libxrpl/tx/transactors/credentials/CredentialAccept.cpp

@@ -1,7 +1,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/CredentialHelpers.h>
-#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TxFlags.h>

src/libxrpl/tx/transactors/credentials/CredentialCreate.cpp

@@ -1,7 +1,8 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/CredentialHelpers.h>
-#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TxFlags.h>
@@ -146,14 +147,15 @@ CredentialCreate::doApply()
     }
     else
     {
+        // Added to both dirs, owned only by issuer. CredentialAccept will transfer ownership to
+        // subject. CredentialDelete will remove from both dirs and decrement 1 ownerCount.
         auto const page =
             view().dirInsert(keylet::ownerDir(subject), credentialKey, describeOwnerDir(subject));
-        JLOG(j_.trace()) << "Adding Credential to owner directory " << to_string(credentialKey.key)
-                         << ": " << (page ? "success" : "failure");
+        JLOG(j_.trace()) << "Adding Credential to subject directory "
+                         << to_string(credentialKey.key) << ": " << (page ? "success" : "failure");
         if (!page)
             return tecDIR_FULL;
         sleCred->setFieldU64(sfSubjectNode, *page);
-        view().update(view().peek(keylet::account(subject)));
     }
 
     view().insert(sleCred);

src/libxrpl/tx/transactors/credentials/CredentialDelete.cpp

@@ -1,7 +1,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/CredentialHelpers.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TxFlags.h>

src/libxrpl/tx/transactors/delegate/DelegateSet.cpp

@@ -1,5 +1,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/st.h>

src/libxrpl/tx/transactors/dex/AMMCreate.cpp

@@ -1,6 +1,7 @@
 #include <xrpl/ledger/OrderBookDB.h>
 #include <xrpl/ledger/Sandbox.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/AMMCore.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/STIssue.h>

src/libxrpl/tx/transactors/dex/AMMDeposit.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/ledger/Sandbox.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/AMMCore.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/TxFlags.h>

src/libxrpl/tx/transactors/dex/OfferCancel.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
 #include <xrpl/protocol/st.h>
 #include <xrpl/tx/transactors/dex/OfferCancel.h>
 

src/libxrpl/tx/transactors/dex/OfferCreate.cpp

@@ -2,6 +2,10 @@
 #include <xrpl/beast/utility/WrappedSink.h>
 #include <xrpl/ledger/OrderBookDB.h>
 #include <xrpl/ledger/PaymentSandbox.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/TER.h>

src/libxrpl/tx/transactors/dex/PermissionedDEXHelpers.cpp

@@ -1,4 +1,4 @@
-#include <xrpl/ledger/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
 #include <xrpl/tx/transactors/dex/PermissionedDEXHelpers.h>
 
 namespace xrpl {

src/libxrpl/tx/transactors/did/DIDDelete.cpp

@@ -1,6 +1,6 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/tx/transactors/did/DIDDelete.h>
 

src/libxrpl/tx/transactors/did/DIDSet.cpp

@@ -1,6 +1,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TxFlags.h>

src/libxrpl/tx/transactors/escrow/EscrowCancel.cpp

@@ -1,8 +1,12 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/MPTokenHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Rate.h>
 #include <xrpl/tx/transactors/escrow/EscrowCancel.h>
 
 #include <libxrpl/tx/transactors/escrow/EscrowHelpers.h>
@@ -191,7 +195,8 @@ EscrowCancel::doApply()
         }
     }
 
-    adjustOwnerCount(ctx_.view(), sle, -1, ctx_.journal);
+    auto const reserveToSubtract = calculateAdditionalReserve((*slep)[~sfFinishFunction]);
+    adjustOwnerCount(ctx_.view(), sle, -1 * reserveToSubtract, ctx_.journal);
     ctx_.view().update(sle);
 
     // Remove escrow from ledger

src/libxrpl/tx/transactors/escrow/EscrowCreate.cpp

@@ -3,9 +3,14 @@
 #include <xrpl/conditions/Condition.h>
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/ledger/helpers/MPTokenHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/MPTAmount.h>
+#include <xrpl/protocol/Rate.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/protocol/XRPAmount.h>
 #include <xrpl/tx/transactors/escrow/EscrowCreate.h>
@@ -87,6 +92,29 @@ escrowCreatePreflightHelper<MPTIssue>(PreflightContext const& ctx)
     return tesSUCCESS;
 }
 
+XRPAmount
+EscrowCreate::calculateBaseFee(ReadView const& view, STTx const& tx)
+{
+    XRPAmount txnFees{Transactor::calculateBaseFee(view, tx)};
+    if (tx.isFieldPresent(sfFinishFunction))
+    {
+        // 10 base fees for the transaction (1 is in
+        // `Transactor::calculateBaseFee`), plus 5 drops per byte
+        txnFees += 9 * view.fees().base + 5 * tx[sfFinishFunction].size();
+    }
+    return txnFees;
+}
+
+bool
+EscrowCreate::checkExtraFeatures(PreflightContext const& ctx)
+{
+    if ((ctx.tx.isFieldPresent(sfFinishFunction) || ctx.tx.isFieldPresent(sfData)) &&
+        !ctx.rules.enabled(featureSmartEscrow))
+        return false;
+
+    return true;
+}
+
 NotTEC
 EscrowCreate::preflight(PreflightContext const& ctx)
 {
@@ -118,12 +146,19 @@ EscrowCreate::preflight(PreflightContext const& ctx)
         ctx.tx[sfCancelAfter] <= ctx.tx[sfFinishAfter])
         return temBAD_EXPIRATION;
 
+    if (ctx.tx.isFieldPresent(sfFinishFunction) && !ctx.tx.isFieldPresent(sfCancelAfter))
+        return temBAD_EXPIRATION;
+
     // In the absence of a FinishAfter, the escrow can be finished
     // immediately, which can be confusing. When creating an escrow,
     // we want to ensure that either a FinishAfter time is explicitly
     // specified or a completion condition is attached.
-    if (!ctx.tx[~sfFinishAfter] && !ctx.tx[~sfCondition])
+    if (!ctx.tx[~sfFinishAfter] && !ctx.tx[~sfCondition] && !ctx.tx[~sfFinishFunction])
+    {
+        JLOG(ctx.j.debug()) << "Must have at least one of FinishAfter, "
+                               "Condition, or FinishFunction.";
         return temMALFORMED;
+    }
 
     if (auto const cb = ctx.tx[~sfCondition])
     {
@@ -139,6 +174,60 @@ EscrowCreate::preflight(PreflightContext const& ctx)
         }
     }
 
+    if (ctx.tx.isFieldPresent(sfData))
+    {
+        if (!ctx.tx.isFieldPresent(sfFinishFunction))
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate with Data requires FinishFunction";
+            return temMALFORMED;
+        }
+        auto const data = ctx.tx.getFieldVL(sfData);
+        if (data.size() > maxWasmDataLength)
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate.Data bad size " << data.size();
+            return temMALFORMED;
+        }
+    }
+
+    if (ctx.tx.isFieldPresent(sfFinishFunction))
+    {
+        auto const fees(ctx.registry.getFees());
+        if (fees.extensionSizeLimit == 0 || fees.extensionComputeLimit == 0)
+        {
+            JLOG(ctx.j.debug()) << "WASM runtime deactivated by fee voting";
+            return temTEMP_DISABLED;
+        }
+
+        auto const code = ctx.tx.getFieldVL(sfFinishFunction);
+        if (code.empty() || code.size() > fees.extensionSizeLimit)
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate.FinishFunction bad size " << code.size();
+            return temMALFORMED;
+        }
+        // actual validity of WASM code happens in `preflightSigValidated`
+        // (after the signature is checked)
+    }
+
+    return tesSUCCESS;
+}
+
+NotTEC
+EscrowCreate::preflightSigValidated(PreflightContext const& ctx)
+{
+    if (ctx.tx.isFieldPresent(sfFinishFunction))
+    {
+        auto const code = ctx.tx.getFieldVL(sfFinishFunction);
+        // basic checks happen in `preflight`
+
+        HostFunctions mock(ctx.j);
+        auto const re = preflightEscrowWasm(code, mock, ESCROW_FUNCTION_NAME);
+        if (!isTesSuccess(re))
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate.FinishFunction bad WASM";
+            return re;
+        }
+    }
+
     return tesSUCCESS;
 }
 
@@ -374,6 +463,17 @@ escrowLockApplyHelper<MPTIssue>(
     return tesSUCCESS;
 }
 
+template <class T>
+static uint32_t
+calculateAdditionalReserve(T const& finishFunction)
+{
+    if (!finishFunction)
+        return 1;
+    // First 500 bytes included in the normal reserve
+    // Each additional 500 bytes requires an additional reserve
+    return 1 + (finishFunction->size() / 500);
+}
+
 TER
 EscrowCreate::doApply()
 {
@@ -391,8 +491,9 @@ EscrowCreate::doApply()
 
     // Check reserve and funds availability
     STAmount const amount{ctx_.tx[sfAmount]};
+    auto const reserveToAdd = calculateAdditionalReserve(ctx_.tx[~sfFinishFunction]);
 
-    auto const reserve = ctx_.view().fees().accountReserve((*sle)[sfOwnerCount] + 1);
+    auto const reserve = ctx_.view().fees().accountReserve((*sle)[sfOwnerCount] + reserveToAdd);
 
     auto const balance = sle->getFieldAmount(sfBalance).xrp();
     if (balance < reserve)
@@ -426,6 +527,8 @@ EscrowCreate::doApply()
     (*slep)[~sfCancelAfter] = ctx_.tx[~sfCancelAfter];
     (*slep)[~sfFinishAfter] = ctx_.tx[~sfFinishAfter];
     (*slep)[~sfDestinationTag] = ctx_.tx[~sfDestinationTag];
+    (*slep)[~sfFinishFunction] = ctx_.tx[~sfFinishFunction];
+    (*slep)[~sfData] = ctx_.tx[~sfData];
 
     if (ctx_.view().rules().enabled(fixIncludeKeyletFields))
     {
@@ -493,7 +596,7 @@ EscrowCreate::doApply()
     }
 
     // increment owner count
-    adjustOwnerCount(ctx_.view(), sle, 1, ctx_.journal);
+    adjustOwnerCount(ctx_.view(), sle, reserveToAdd, ctx_.journal);
     ctx_.view().update(sle);
     return tesSUCCESS;
 }

src/libxrpl/tx/transactors/escrow/EscrowFinish.cpp

@@ -4,10 +4,13 @@
 #include <xrpl/conditions/Fulfillment.h>
 #include <xrpl/core/HashRouter.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/CredentialHelpers.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/MPTokenHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Rate.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/protocol/XRPAmount.h>
 #include <xrpl/tx/transactors/escrow/EscrowFinish.h>
@@ -45,7 +48,14 @@ checkCondition(Slice f, Slice c)
 bool
 EscrowFinish::checkExtraFeatures(PreflightContext const& ctx)
 {
-    return !ctx.tx.isFieldPresent(sfCredentialIDs) || ctx.rules.enabled(featureCredentials);
+    if (ctx.tx.isFieldPresent(sfCredentialIDs) && !ctx.rules.enabled(featureCredentials))
+        return false;
+
+    if (ctx.tx.isFieldPresent(sfComputationAllowance) && !ctx.rules.enabled(featureSmartEscrow))
+    {
+        return false;
+    }
+    return true;
 }
 
 NotTEC
@@ -57,7 +67,32 @@ EscrowFinish::preflight(PreflightContext const& ctx)
     // If you specify a condition, then you must also specify
     // a fulfillment.
     if (static_cast<bool>(cb) != static_cast<bool>(fb))
+    {
+        JLOG(ctx.j.debug()) << "Condition != Fulfillment";
         return temMALFORMED;
+    }
+
+    if (auto const allowance = ctx.tx[~sfComputationAllowance]; allowance)
+    {
+        auto const fees(ctx.registry.getFees());
+        if (fees.extensionComputeLimit == 0)
+        {
+            JLOG(ctx.j.debug()) << "WASM runtime deactivated by fee voting";
+            return temTEMP_DISABLED;
+        }
+        if (*allowance == 0)
+        {
+            return temBAD_LIMIT;
+        }
+        if (*allowance > fees.extensionComputeLimit)
+        {
+            JLOG(ctx.j.debug()) << "ComputationAllowance too large: " << *allowance;
+            return temBAD_LIMIT;
+        }
+    }
+
+    if (auto const err = credentials::checkFields(ctx.tx, ctx.j); !isTesSuccess(err))
+        return err;
 
     return tesSUCCESS;
 }
@@ -91,9 +126,6 @@ EscrowFinish::preflightSigValidated(PreflightContext const& ctx)
         }
     }
 
-    if (auto const err = credentials::checkFields(ctx.tx, ctx.j); !isTesSuccess(err))
-        return err;
-
     return tesSUCCESS;
 }
 
@@ -106,7 +138,15 @@ EscrowFinish::calculateBaseFee(ReadView const& view, STTx const& tx)
     {
         extraFee += view.fees().base * (32 + (fb->size() / 16));
     }
-
+    if (std::optional<uint64_t> const allowance = tx[~sfComputationAllowance]; allowance)
+    {
+        // The extra fee is the allowance in drops, rounded up to the nearest
+        // whole drop.
+        // Integer math rounds down by default, so we add 1 to round up.
+        uint64_t const allowanceFee =
+            ((*allowance) * view.fees().gasPrice) / MICRO_DROPS_PER_DROP + 1;
+        extraFee += allowanceFee;
+    }
     return Transactor::calculateBaseFee(view, tx) + extraFee;
 }
 
@@ -182,25 +222,50 @@ EscrowFinish::preclaim(PreclaimContext const& ctx)
             return err;
     }
 
-    if (ctx.view.rules().enabled(featureTokenEscrow))
+    if (ctx.view.rules().enabled(featureTokenEscrow) ||
+        ctx.view.rules().enabled(featureSmartEscrow))
     {
+        // this check is done in doApply before this amendment is enabled
         auto const k = keylet::escrow(ctx.tx[sfOwner], ctx.tx[sfOfferSequence]);
         auto const slep = ctx.view.read(k);
         if (!slep)
             return tecNO_TARGET;
 
-        AccountID const dest = (*slep)[sfDestination];
-        STAmount const amount = (*slep)[sfAmount];
-
-        if (!isXRP(amount))
+        if (ctx.view.rules().enabled(featureSmartEscrow))
         {
-            if (auto const ret = std::visit(
-                    [&]<typename T>(T const&) {
-                        return escrowFinishPreclaimHelper<T>(ctx, dest, amount);
-                    },
-                    amount.asset().value());
-                !isTesSuccess(ret))
-                return ret;
+            if (slep->isFieldPresent(sfFinishFunction))
+            {
+                if (!ctx.tx.isFieldPresent(sfComputationAllowance))
+                {
+                    JLOG(ctx.j.debug()) << "FinishFunction requires ComputationAllowance";
+                    return tefWASM_FIELD_NOT_INCLUDED;
+                }
+            }
+            else
+            {
+                if (ctx.tx.isFieldPresent(sfComputationAllowance))
+                {
+                    JLOG(ctx.j.debug()) << "FinishFunction not present, "
+                                           "ComputationAllowance present";
+                    return tefNO_WASM;
+                }
+            }
+        }
+        if (ctx.view.rules().enabled(featureTokenEscrow))
+        {
+            AccountID const dest = (*slep)[sfDestination];
+            STAmount const amount = (*slep)[sfAmount];
+
+            if (!isXRP(amount))
+            {
+                if (auto const ret = std::visit(
+                        [&]<typename T>(T const&) {
+                            return escrowFinishPreclaimHelper<T>(ctx, dest, amount);
+                        },
+                        amount.asset().value());
+                    !isTesSuccess(ret))
+                    return ret;
+            }
         }
     }
     return tesSUCCESS;
@@ -213,7 +278,8 @@ EscrowFinish::doApply()
     auto const slep = ctx_.view().peek(k);
     if (!slep)
     {
-        if (ctx_.view().rules().enabled(featureTokenEscrow))
+        if (ctx_.view().rules().enabled(featureTokenEscrow) ||
+            ctx_.view().rules().enabled(featureSmartEscrow))
             return tecINTERNAL;  // LCOV_EXCL_LINE
 
         return tecNO_TARGET;
@@ -231,6 +297,20 @@ EscrowFinish::doApply()
     if ((*slep)[~sfCancelAfter] && after(now, (*slep)[sfCancelAfter]))
         return tecNO_PERMISSION;
 
+    AccountID const destID = (*slep)[sfDestination];
+    auto const sled = ctx_.view().peek(keylet::account(destID));
+    if (ctx_.view().rules().enabled(featureSmartEscrow))
+    {
+        // NOTE: Escrow payments cannot be used to fund accounts.
+        if (!sled)
+            return tecNO_DST;
+
+        if (auto err =
+                verifyDepositPreauth(ctx_.tx, ctx_.view(), account_, destID, sled, ctx_.journal);
+            !isTesSuccess(err))
+            return err;
+    }
+
     // Check cryptocondition fulfillment
     {
         auto const id = ctx_.tx.getTransactionID();
@@ -284,15 +364,71 @@ EscrowFinish::doApply()
             return tecCRYPTOCONDITION_ERROR;
     }
 
-    // NOTE: Escrow payments cannot be used to fund accounts.
-    AccountID const destID = (*slep)[sfDestination];
-    auto const sled = ctx_.view().peek(keylet::account(destID));
-    if (!sled)
-        return tecNO_DST;
+    if (!ctx_.view().rules().enabled(featureSmartEscrow))
+    {
+        // NOTE: Escrow payments cannot be used to fund accounts.
+        if (!sled)
+            return tecNO_DST;
 
-    if (auto err = verifyDepositPreauth(ctx_.tx, ctx_.view(), account_, destID, sled, ctx_.journal);
-        !isTesSuccess(err))
-        return err;
+        if (auto err =
+                verifyDepositPreauth(ctx_.tx, ctx_.view(), account_, destID, sled, ctx_.journal);
+            !isTesSuccess(err))
+            return err;
+    }
+
+    // Execute custom release function
+    if ((*slep)[~sfFinishFunction])
+    {
+        JLOG(j_.trace()) << "The escrow has a finish function, running WASM code...";
+        // WASM execution
+        auto const wasmStr = slep->getFieldVL(sfFinishFunction);
+        std::vector<uint8_t> wasm(wasmStr.begin(), wasmStr.end());
+
+        WasmHostFunctionsImpl ledgerDataProvider(ctx_, k);
+
+        if (!ctx_.tx.isFieldPresent(sfComputationAllowance))
+        {
+            // already checked above, this check is just in case
+            return tecINTERNAL;
+        }
+        std::uint32_t const allowance = ctx_.tx[sfComputationAllowance];
+        auto re = runEscrowWasm(wasm, ledgerDataProvider, allowance, ESCROW_FUNCTION_NAME);
+        JLOG(j_.trace()) << "Escrow WASM ran";
+
+        if (auto const& data = ledgerDataProvider.getData(); data.has_value())
+        {
+            if (data->size() > maxWasmDataLength)
+            {
+                // should already be checked in the updateData host function
+                return tecINTERNAL;  // LCOV_EXCL_LINE
+            }
+            slep->setFieldVL(sfData, makeSlice(*data));
+            ctx_.view().update(slep);
+        }
+
+        if (re.has_value())
+        {
+            auto const reValue = re.value().result;
+            auto const reCost = re.value().cost;
+            JLOG(j_.debug()) << "WASM Success: " + std::to_string(reValue) << ", cost: " << reCost;
+
+            ctx_.setWasmReturnCode(reValue);
+
+            if (reCost < 0 || reCost > std::numeric_limits<uint32_t>::max())
+                return tecINTERNAL;  // LCOV_EXCL_LINE
+            ctx_.setGasUsed(static_cast<uint32_t>(reCost));
+
+            if (reValue <= 0)
+            {
+                return tecWASM_REJECTED;
+            }
+        }
+        else
+        {
+            JLOG(j_.debug()) << "WASM Failure: " + transHuman(re.error());
+            return re.error();
+        }
+    }
 
     AccountID const account = (*slep)[sfAccount];
 
@@ -369,9 +505,11 @@ EscrowFinish::doApply()
 
     ctx_.view().update(sled);
 
+    auto const reserveToSubtract = calculateAdditionalReserve((*slep)[~sfFinishFunction]);
+
     // Adjust source owner count
     auto const sle = ctx_.view().peek(keylet::account(account));
-    adjustOwnerCount(ctx_.view(), sle, -1, ctx_.journal);
+    adjustOwnerCount(ctx_.view(), sle, -1 * reserveToSubtract, ctx_.journal);
     ctx_.view().update(sle);
 
     // Remove escrow from ledger

src/libxrpl/tx/transactors/escrow/EscrowHelpers.h

@@ -3,9 +3,13 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/MPTokenHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/MPTAmount.h>
+#include <xrpl/protocol/Rate.h>
 #include <xrpl/tx/transactors/token/MPTokenAuthorize.h>
 
 namespace xrpl {

src/libxrpl/tx/transactors/lending/LoanBrokerCoverClawback.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/tx/transactors/lending/LoanBrokerCoverClawback.h>
 //
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/tx/transactors/lending/LendingHelpers.h>
 

src/libxrpl/tx/transactors/lending/LoanBrokerCoverDeposit.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/tx/transactors/lending/LoanBrokerCoverDeposit.h>
 //
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/tx/transactors/lending/LendingHelpers.h>
 

src/libxrpl/tx/transactors/lending/LoanBrokerCoverWithdraw.cpp

@@ -1,6 +1,8 @@
 #include <xrpl/tx/transactors/lending/LoanBrokerCoverWithdraw.h>
 //
-#include <xrpl/ledger/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/tx/transactors/lending/LendingHelpers.h>
 #include <xrpl/tx/transactors/payment/Payment.h>

src/libxrpl/tx/transactors/lending/LoanBrokerDelete.cpp

@@ -1,5 +1,7 @@
 #include <xrpl/tx/transactors/lending/LoanBrokerDelete.h>
 //
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/tx/transactors/lending/LendingHelpers.h>
 

src/libxrpl/tx/transactors/lending/LoanBrokerSet.cpp

@@ -1,5 +1,7 @@
 #include <xrpl/tx/transactors/lending/LoanBrokerSet.h>
 //
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/tx/transactors/lending/LendingHelpers.h>
 

src/libxrpl/tx/transactors/lending/LoanDelete.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/tx/transactors/lending/LoanDelete.h>
 //
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/tx/transactors/lending/LendingHelpers.h>
 

src/libxrpl/tx/transactors/lending/LoanManage.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/tx/transactors/lending/LoanManage.h>
 //
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/tx/transactors/lending/LendingHelpers.h>

src/libxrpl/tx/transactors/lending/LoanPay.cpp

@@ -1,6 +1,7 @@
 #include <xrpl/tx/transactors/lending/LoanPay.h>
 //
 #include <xrpl/json/to_string.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/Protocol.h>
 #include <xrpl/protocol/STTakesAsset.h>
 #include <xrpl/protocol/TxFlags.h>