feat: Move VaultClawback invariants from ValidVault to VaultClawback

Port the full ttVAULT_CLAWBACK invariant block from ValidVault::finalize
into VaultClawback::finalizeInvariants, following the pattern established
for VaultCreate. Extend VaultInvariantData with the balance-delta tracking
infrastructure (DeltaInfo, visitEntry, deltaAssets, deltaShares, etc.)
previously duplicated in ValidVault, so both per-transaction invariant
classes can share it without depending on ValidVault internals.

include/xrpl/tx/invariants/VaultInvariantData.h

@@ -0,0 +1,177 @@
+#pragma once
+
+#include <xrpl/basics/Number.h>
+#include <xrpl/basics/base_uint.h>
+#include <xrpl/beast/utility/Zero.h>
+#include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/Asset.h>
+#include <xrpl/protocol/MPTIssue.h>
+#include <xrpl/protocol/Rules.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/STTx.h>
+#include <xrpl/protocol/XRPAmount.h>
+
+#include <cstdint>
+#include <optional>
+#include <unordered_map>
+#include <vector>
+
+namespace xrpl {
+
+/**
+ * @brief Collects vault and share-issuance snapshots from ledger entry visits,
+ *        including full balance-delta tracking.
+ *
+ * Used by per-transaction invariant checks (e.g. VaultCreate, VaultClawback)
+ * that need vault, MPTokenIssuance state and balance-delta information.
+ */
+class VaultInvariantData
+{
+public:
+    struct Vault
+    {
+        uint256 key = beast::kZero;
+        Asset asset;
+        AccountID pseudoId;
+        AccountID owner;
+        uint192 shareMPTID = beast::kZero;
+        Number assetsTotal = 0;
+        Number assetsAvailable = 0;
+        Number assetsMaximum = 0;
+        Number lossUnrealized = 0;
+
+        static Vault
+        make(SLE const&);
+    };
+
+    struct Shares
+    {
+        MPTIssue share;
+        std::uint64_t sharesTotal = 0;
+        std::uint64_t sharesMaximum = 0;
+
+        static Shares
+        make(SLE const&);
+    };
+
+    struct DeltaInfo
+    {
+        Number delta = kNumZero;
+        std::optional<int> scale;
+
+        /**
+         * @brief Compute the delta between two Numbers, taking the coarsest
+         *        scale.
+         */
+        [[nodiscard]] static DeltaInfo
+        makeDelta(Number const& before, Number const& after, Asset const& asset);
+    };
+
+    void
+    visitEntry(bool isDelete, SLE::const_ref before, SLE::const_ref after);
+
+    [[nodiscard]] std::vector<Vault> const&
+    afterVaults() const
+    {
+        return afterVault_;
+    }
+
+    [[nodiscard]] std::vector<Vault> const&
+    beforeVaults() const
+    {
+        return beforeVault_;
+    }
+
+    /** Find shares in afterMPTs_ whose mptID matches. */
+    [[nodiscard]] std::optional<Shares>
+    findShares(uint192 const& mptID) const;
+
+    /**
+     * @brief Find a deleted MPTokenIssuance (beforeMPTs_) whose mptID matches.
+     *
+     * Returns the Shares snapshot captured before the entry was deleted,
+     * or nullopt if no matching entry was found.
+     */
+    [[nodiscard]] std::optional<Shares>
+    findDeletedShares(uint192 const& mptID) const;
+
+    /**
+     * @brief Return the before-MPT issuances vector (for deleted entries).
+     */
+    [[nodiscard]] std::vector<Shares> const&
+    beforeMPTIssuances() const
+    {
+        return beforeMPTs_;
+    }
+
+    /**
+     * @brief Return the vault-asset balance-change delta for an account.
+     *
+     * Looks up the ledger-entry delta for the account entry (XRP), trust line
+     * (IOU), or MPToken (MPT) that corresponds to the vault asset held by
+     * @p id.
+     *
+     * @param id Account whose asset delta is requested.
+     * @returns The delta, or nullopt if the entry was not touched.
+     */
+    [[nodiscard]] std::optional<DeltaInfo>
+    deltaAssets(AccountID const& id) const;
+
+    /**
+     * @brief Return the vault-asset delta for the transaction's sending
+     *        account, adjusted for the fee.
+     *
+     * Calls deltaAssets for tx[sfAccount] and, for non-delegated XRP
+     * transactions, adds the consumed fee back so the invariant sees the net
+     * asset movement rather than the fee-reduced balance change.
+     *
+     * @param tx  The transaction being applied.
+     * @param fee Fee charged by this transaction.
+     * @returns The fee-adjusted delta, or nullopt if the net delta is zero or
+     *          the account entry was not touched.
+     */
+    [[nodiscard]] std::optional<DeltaInfo>
+    deltaAssetsTxAccount(STTx const& tx, XRPAmount fee) const;
+
+    /**
+     * @brief Return the vault-share balance-change delta for an account.
+     *
+     * For the vault's pseudo-account the MPTokenIssuance outstanding-amount
+     * delta is returned; for all other accounts the MPToken delta is returned.
+     *
+     * @param id Account whose share delta is requested.
+     * @returns The delta, or nullopt if the entry was not touched.
+     */
+    [[nodiscard]] std::optional<DeltaInfo>
+    deltaShares(AccountID const& id) const;
+
+    /**
+     * @brief Compute the coarsest scale required to represent all numbers.
+     */
+    [[nodiscard]] static std::int32_t
+    computeCoarsestScale(std::vector<DeltaInfo> const& numbers);
+
+    /**
+     * @brief Compute the minimum STAmount scale for rounding invariant
+     *        calculations.
+     *
+     * Post-amendment (fixCleanup3_2_0) this is simply the posterior
+     * assetsTotal scale.  Pre-amendment it is the coarsest scale across
+     * vaultDelta and both asset-field deltas.
+     *
+     * @param vaultDelta Delta of the vault's asset balance for this transaction.
+     * @param rules      Active ledger rules (used to check the amendment).
+     * @returns The minimum scale to apply when rounding vault-related amounts.
+     */
+    [[nodiscard]] std::int32_t
+    computeVaultMinScale(DeltaInfo const& vaultDelta, Rules const& rules) const;
+
+private:
+    std::vector<Vault> afterVault_;
+    std::vector<Vault> beforeVault_;
+    std::vector<Shares> afterMPTs_;
+    std::vector<Shares> beforeMPTs_;
+    std::unordered_map<uint256, DeltaInfo> deltas_;
+};
+
+}  // namespace xrpl

include/xrpl/tx/transactors/vault/VaultClawback.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <xrpl/tx/Transactor.h>
+#include <xrpl/tx/invariants/VaultInvariantData.h>
 
 namespace xrpl {
 
@@ -34,6 +35,8 @@ public:
         beast::Journal const& j) override;
 
 private:
+    VaultInvariantData data_;
+
     Expected<std::pair<STAmount, STAmount>, TER>
     assetsToClawback(
         SLE::ref vault,

include/xrpl/tx/transactors/vault/VaultCreate.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <xrpl/tx/Transactor.h>
+#include <xrpl/tx/invariants/VaultInvariantData.h>
 
 namespace xrpl {
 
@@ -38,6 +39,9 @@ public:
         XRPAmount fee,
         ReadView const& view,
         beast::Journal const& j) override;
+
+private:
+    VaultInvariantData data_;
 };
 
 }  // namespace xrpl

src/libxrpl/tx/invariants/VaultInvariant.cpp

@@ -5,7 +5,6 @@
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/ledger/ReadView.h>
-#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -525,9 +524,8 @@ ValidVault::finalize(
     }();
 
     if (!beforeShares &&
-        (tx.getTxnType() == ttVAULT_DEPOSIT ||   //
-         tx.getTxnType() == ttVAULT_WITHDRAW ||  //
-         tx.getTxnType() == ttVAULT_CLAWBACK))
+        (tx.getTxnType() == ttVAULT_DEPOSIT ||  //
+         tx.getTxnType() == ttVAULT_WITHDRAW))
     {
         JLOG(j.fatal()) << "Invariant failed: vault operation succeeded "
                            "without updating shares";
@@ -544,61 +542,15 @@ ValidVault::finalize(
     result &= [&]() {
         switch (txnType)
         {
-            case ttVAULT_CREATE: {
-                bool result = true;
-
-                if (!beforeVault_.empty())
-                {
-                    JLOG(j.fatal())  //
-                        << "Invariant failed: create operation must not have "
-                           "updated a vault";
-                    result = false;
-                }
-
-                if (afterVault.assetsAvailable != kZero || afterVault.assetsTotal != kZero ||
-                    afterVault.lossUnrealized != kZero || updatedShares->sharesTotal != 0)
-                {
-                    JLOG(j.fatal())  //
-                        << "Invariant failed: created vault must be empty";
-                    result = false;
-                }
-
-                if (afterVault.pseudoId != updatedShares->share.getIssuer())
-                {
-                    JLOG(j.fatal())  //
-                        << "Invariant failed: shares issuer and vault "
-                           "pseudo-account must be the same";
-                    result = false;
-                }
-
-                auto const sleSharesIssuer =
-                    view.read(keylet::account(updatedShares->share.getIssuer()));
-                if (!sleSharesIssuer)
-                {
-                    JLOG(j.fatal())  //
-                        << "Invariant failed: shares issuer must exist";
-                    return false;
-                }
-
-                if (!isPseudoAccount(sleSharesIssuer))
-                {
-                    JLOG(j.fatal())  //
-                        << "Invariant failed: shares issuer must be a "
-                           "pseudo-account";
-                    result = false;
-                }
-
-                if (auto const vaultId = (*sleSharesIssuer)[~sfVaultID];
-                    !vaultId || *vaultId != afterVault.key)
-                {
-                    JLOG(j.fatal())  //
-                        << "Invariant failed: shares issuer pseudo-account "
-                           "must point back to the vault";
-                    result = false;
-                }
-
-                return result;
-            }
+            case ttVAULT_CREATE:
+            case ttVAULT_CLAWBACK:
+            case ttLOAN_SET:
+            case ttLOAN_MANAGE:
+            case ttLOAN_PAY:
+                // Create-specific checks live in VaultCreate::finalizeInvariants.
+                // Clawback-specific checks live in VaultClawback::finalizeInvariants.
+                // Loan checks are TBD.
+                return true;
             case ttVAULT_SET: {
                 bool result = true;
 
@@ -947,108 +899,6 @@ ValidVault::finalize(
 
                 return result;
             }
-            case ttVAULT_CLAWBACK: {
-                bool result = true;
-
-                XRPL_ASSERT(
-                    !beforeVault_.empty(), "xrpl::ValidVault::finalize : clawback updated a vault");
-                auto const& beforeVault = beforeVault_[0];
-
-                if (vaultAsset.native() || vaultAsset.getIssuer() != tx[sfAccount])
-                {
-                    // The owner can use clawback to force-burn shares when the
-                    // vault is empty but there are outstanding shares
-                    if (!(beforeShares && beforeShares->sharesTotal > 0 &&
-                          isVaultEmpty(beforeVault) && beforeVault.owner == tx[sfAccount]))
-                    {
-                        JLOG(j.fatal()) << "Invariant failed: " <<  //
-                            "clawback may only be performed by the asset issuer, or by the vault "
-                            "owner of an empty vault";
-                        return false;  // That's all we can do
-                    }
-                }
-
-                auto const maybeVaultDeltaAssets = deltaAssets(afterVault.pseudoId);
-                if (maybeVaultDeltaAssets)
-                {
-                    auto const minScale =
-                        computeVaultMinScale(*maybeVaultDeltaAssets, view.rules());
-                    auto const vaultDeltaAssets =
-                        roundToAsset(vaultAsset, maybeVaultDeltaAssets->delta, minScale);
-                    if (vaultDeltaAssets >= kZero)
-                    {
-                        JLOG(j.fatal()) << "Invariant failed: clawback must decrease vault balance";
-                        result = false;
-                    }
-
-                    auto const assetsTotalDelta = roundToAsset(
-                        vaultAsset, afterVault.assetsTotal - beforeVault.assetsTotal, minScale);
-                    if (assetsTotalDelta != vaultDeltaAssets)
-                    {
-                        JLOG(j.fatal()) <<  //
-                            "Invariant failed: clawback and assets outstanding must add up";
-                        result = false;
-                    }
-
-                    auto const assetAvailableDelta = roundToAsset(
-                        vaultAsset,
-                        afterVault.assetsAvailable - beforeVault.assetsAvailable,
-                        minScale);
-                    if (assetAvailableDelta != vaultDeltaAssets)
-                    {
-                        JLOG(j.fatal()) <<  //
-                            "Invariant failed: clawback and assets available must add up";
-                        result = false;
-                    }
-                }
-                else if (!isVaultEmpty(beforeVault))
-                {
-                    JLOG(j.fatal()) <<  //
-                        "Invariant failed: clawback must change vault balance";
-                    return false;  // That's all we can do
-                }
-
-                // We don't need to round shares, they are integral MPT
-                auto const maybeAccountDeltaShares = deltaShares(tx[sfHolder]);
-                if (!maybeAccountDeltaShares)
-                {
-                    JLOG(j.fatal()) <<  //
-                        "Invariant failed: clawback must change holder shares";
-                    return false;  // That's all we can do
-                }
-                if (maybeAccountDeltaShares->delta >= kZero)
-                {
-                    JLOG(j.fatal()) <<  //
-                        "Invariant failed: clawback must decrease holder shares";
-                    result = false;
-                }
-
-                // We don't need to round shares, they are integral MPT
-                auto const vaultDeltaShares = deltaShares(afterVault.pseudoId);
-                if (!vaultDeltaShares || vaultDeltaShares->delta == kZero)
-                {
-                    JLOG(j.fatal()) <<  //
-                        "Invariant failed: clawback must change vault shares";
-                    return false;  // That's all we can do
-                }
-
-                if (vaultDeltaShares->delta * -1 != maybeAccountDeltaShares->delta)
-                {
-                    JLOG(j.fatal()) << "Invariant failed: " <<  //
-                        "clawback must change holder and vault shares by equal amount";
-                    result = false;
-                }
-
-                return result;
-            }
-
-            case ttLOAN_SET:
-            case ttLOAN_MANAGE:
-            case ttLOAN_PAY: {
-                // TBD
-                return true;
-            }
-
             default:
                 // LCOV_EXCL_START
                 UNREACHABLE("xrpl::ValidVault::finalize : unknown transaction type");

src/libxrpl/tx/invariants/VaultInvariantData.cpp

@@ -0,0 +1,313 @@
+#include <xrpl/tx/invariants/VaultInvariantData.h>
+
+#include <xrpl/basics/Number.h>
+#include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Issue.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/Protocol.h>
+#include <xrpl/protocol/Rules.h>
+#include <xrpl/protocol/SField.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/STNumber.h>  // IWYU pragma: keep
+#include <xrpl/protocol/STTx.h>
+#include <xrpl/protocol/XRPAmount.h>
+
+#include <algorithm>
+#include <cstdint>
+#include <optional>
+#include <variant>
+#include <vector>
+
+namespace xrpl {
+
+VaultInvariantData::Vault
+VaultInvariantData::Vault::make(SLE const& from)
+{
+    XRPL_ASSERT(from.getType() == ltVAULT, "VaultInvariantData::Vault::make : from Vault object");
+
+    Vault self;
+    self.key = from.key();
+    self.asset = from.at(sfAsset);
+    self.pseudoId = from.getAccountID(sfAccount);
+    self.owner = from.at(sfOwner);
+    self.shareMPTID = from.getFieldH192(sfShareMPTID);
+    self.assetsTotal = from.at(sfAssetsTotal);
+    self.assetsAvailable = from.at(sfAssetsAvailable);
+    self.assetsMaximum = from.at(sfAssetsMaximum);
+    self.lossUnrealized = from.at(sfLossUnrealized);
+    return self;
+}
+
+VaultInvariantData::Shares
+VaultInvariantData::Shares::make(SLE const& from)
+{
+    XRPL_ASSERT(
+        from.getType() == ltMPTOKEN_ISSUANCE,
+        "VaultInvariantData::Shares::make : from MPTokenIssuance object");
+
+    Shares self;
+    self.share = MPTIssue(makeMptID(from.getFieldU32(sfSequence), from.getAccountID(sfIssuer)));
+    self.sharesTotal = from.getFieldU64(sfOutstandingAmount);
+    self.sharesMaximum = from[~sfMaximumAmount].value_or(kMaxMpTokenAmount);
+    return self;
+}
+
+void
+VaultInvariantData::visitEntry(bool isDelete, SLE::const_ref before, SLE::const_ref after)
+{
+    XRPL_ASSERT(
+        after != nullptr && (before != nullptr || !isDelete),
+        "xrpl::VaultInvariantData::visitEntry : some object is available");
+
+    // Number balanceDelta will capture the difference (delta) between "before"
+    // state (zero if created) and "after" state (zero if destroyed), and
+    // preserves value scale (exponent) to round values to the same scale during
+    // validation. It is used to validate that the change in account
+    // balances matches the change in vault balances, stored to deltas_ at the
+    // end of this function.
+    DeltaInfo balanceDelta{.delta = kNumZero, .scale = std::nullopt};
+
+    std::int8_t sign = 0;
+    if (before)
+    {
+        switch (before->getType())
+        {
+            case ltVAULT:
+                beforeVault_.push_back(Vault::make(*before));
+                break;
+            case ltMPTOKEN_ISSUANCE:
+                // At this moment we have no way of telling if this object holds
+                // vault shares or something else. Save it for finalize.
+                beforeMPTs_.push_back(Shares::make(*before));
+                balanceDelta.delta =
+                    static_cast<std::int64_t>(before->getFieldU64(sfOutstandingAmount));
+                // MPTs are ints, so the scale is always 0.
+                balanceDelta.scale = 0;
+                sign = 1;
+                break;
+            case ltMPTOKEN:
+                balanceDelta.delta = static_cast<std::int64_t>(before->getFieldU64(sfMPTAmount));
+                // MPTs are ints, so the scale is always 0.
+                balanceDelta.scale = 0;
+                sign = -1;
+                break;
+            case ltACCOUNT_ROOT:
+                balanceDelta.delta = before->getFieldAmount(sfBalance);
+                // Account balance is XRP, which is an int, so the scale is
+                // always 0.
+                balanceDelta.scale = 0;
+                sign = -1;
+                break;
+            case ltRIPPLE_STATE: {
+                auto const amount = before->getFieldAmount(sfBalance);
+                balanceDelta.delta = amount;
+                // Trust Line balances are STAmounts, so we can use the exponent
+                // directly to get the scale.
+                balanceDelta.scale = amount.exponent();
+                sign = -1;
+                break;
+            }
+            default:;
+        }
+    }
+
+    if (!isDelete && after)
+    {
+        switch (after->getType())
+        {
+            case ltVAULT:
+                afterVault_.push_back(Vault::make(*after));
+                break;
+            case ltMPTOKEN_ISSUANCE:
+                // At this moment we have no way of telling if this object holds
+                // vault shares or something else. Save it for finalize.
+                afterMPTs_.push_back(Shares::make(*after));
+                balanceDelta.delta -=
+                    Number(static_cast<std::int64_t>(after->getFieldU64(sfOutstandingAmount)));
+                // MPTs are ints, so the scale is always 0.
+                balanceDelta.scale = 0;
+                sign = 1;
+                break;
+            case ltMPTOKEN:
+                balanceDelta.delta -=
+                    Number(static_cast<std::int64_t>(after->getFieldU64(sfMPTAmount)));
+                // MPTs are ints, so the scale is always 0.
+                balanceDelta.scale = 0;
+                sign = -1;
+                break;
+            case ltACCOUNT_ROOT:
+                balanceDelta.delta -= Number(after->getFieldAmount(sfBalance));
+                // Account balance is XRP, which is an int, so the scale is
+                // always 0.
+                balanceDelta.scale = 0;
+                sign = -1;
+                break;
+            case ltRIPPLE_STATE: {
+                auto const amount = after->getFieldAmount(sfBalance);
+                balanceDelta.delta -= Number(amount);
+                // Trust Line balances are STAmounts, so we can use the exponent
+                // directly to get the scale.
+                if (amount.exponent() > balanceDelta.scale)
+                    balanceDelta.scale = amount.exponent();
+                sign = -1;
+                break;
+            }
+            default:;
+        }
+    }
+
+    uint256 const key = (before ? before->key() : after->key());
+    // Append to deltas if sign is non-zero, i.e. an object of an interesting
+    // type has been updated. A transaction may update an object even when
+    // its balance has not changed, e.g. transaction fee equals the amount
+    // transferred to the account. We intentionally do not compare balanceDelta
+    // against zero, to avoid missing such updates.
+    if (sign != 0)
+    {
+        XRPL_ASSERT_PARTS(
+            balanceDelta.scale, "xrpl::VaultInvariantData::visitEntry", "scale initialized");
+        balanceDelta.delta *= sign;
+        deltas_[key] = balanceDelta;
+    }
+}
+
+std::optional<VaultInvariantData::Shares>
+VaultInvariantData::findShares(uint192 const& mptID) const
+{
+    for (auto const& s : afterMPTs_)
+    {
+        if (s.share.getMptID() == mptID)
+            return s;
+    }
+    return std::nullopt;
+}
+
+std::optional<VaultInvariantData::Shares>
+VaultInvariantData::findDeletedShares(uint192 const& mptID) const
+{
+    for (auto const& s : beforeMPTs_)
+    {
+        if (s.share.getMptID() == mptID)
+            return s;
+    }
+    return std::nullopt;
+}
+
+std::optional<VaultInvariantData::DeltaInfo>
+VaultInvariantData::deltaAssets(AccountID const& id) const
+{
+    auto const& vaultAsset = afterVault_[0].asset;
+    auto const lookup = [&](uint256 const& key) -> std::optional<DeltaInfo> {
+        auto const it = deltas_.find(key);
+        if (it == deltas_.end())
+            return std::nullopt;
+        return it->second;
+    };
+
+    return std::visit(
+        [&]<typename TIss>(TIss const& issue) -> std::optional<DeltaInfo> {
+            if constexpr (std::is_same_v<TIss, Issue>)
+            {
+                if (isXRP(issue))
+                    return lookup(keylet::account(id).key);
+                auto result = lookup(keylet::line(id, issue).key);
+                // Trust-line balance is stored from the low-account's perspective;
+                // negate if id is the high account so the delta is in id's terms.
+                if (result && id > issue.getIssuer())
+                    result->delta = -result->delta;
+                return result;
+            }
+            else if constexpr (std::is_same_v<TIss, MPTIssue>)
+            {
+                return lookup(keylet::mptoken(issue.getMptID(), id).key);
+            }
+        },
+        vaultAsset.value());
+}
+
+std::optional<VaultInvariantData::DeltaInfo>
+VaultInvariantData::deltaAssetsTxAccount(STTx const& tx, XRPAmount fee) const
+{
+    static constexpr Number kZero{};
+    auto const& vaultAsset = afterVault_[0].asset;
+    auto ret = deltaAssets(tx[sfAccount]);
+    if (!ret.has_value() || !vaultAsset.native())
+        return ret;
+
+    if (auto const delegate = tx[~sfDelegate]; delegate.has_value() && *delegate != tx[sfAccount])
+        return ret;
+
+    ret->delta += fee.drops();
+    if (ret->delta == kZero)
+        return std::nullopt;
+
+    return ret;
+}
+
+std::optional<VaultInvariantData::DeltaInfo>
+VaultInvariantData::deltaShares(AccountID const& id) const
+{
+    auto const& afterVault = afterVault_[0];
+    auto const it = [&]() {
+        if (id == afterVault.pseudoId)
+            return deltas_.find(keylet::mptIssuance(afterVault.shareMPTID).key);
+        return deltas_.find(keylet::mptoken(afterVault.shareMPTID, id).key);
+    }();
+
+    return it != deltas_.end() ? std::optional<DeltaInfo>(it->second) : std::nullopt;
+}
+
+[[nodiscard]] VaultInvariantData::DeltaInfo
+VaultInvariantData::DeltaInfo::makeDelta(
+    Number const& before,
+    Number const& after,
+    Asset const& asset)
+{
+    return {
+        .delta = after - before,
+        .scale = std::max(xrpl::scale(after, asset), xrpl::scale(before, asset))};
+}
+
+[[nodiscard]] std::int32_t
+VaultInvariantData::computeCoarsestScale(std::vector<DeltaInfo> const& numbers)
+{
+    if (numbers.empty())
+        return 0;
+
+    auto const max = std::ranges::max_element(
+        numbers, [](auto const& a, auto const& b) -> bool { return a.scale < b.scale; });
+    XRPL_ASSERT_PARTS(
+        max->scale, "xrpl::VaultInvariantData::computeCoarsestScale", "scale set for delta");
+    return max->scale.value_or(STAmount::kMaxOffset);
+}
+
+std::int32_t
+VaultInvariantData::computeVaultMinScale(DeltaInfo const& vaultDelta, Rules const& rules) const
+{
+    // Returns the posterior `assetsTotal` scale.
+    //
+    // 1. Because STAmounts are normalized, `assetsTotal` (being >= `assetsAvailable`)
+    // safely represents the coarsest exponent needed for both fields.
+    //
+    // 2. The scale may decrease (withdraw/clawback) or increase (deposit). In both cases
+    // we ensure the vault is in a legitimate state in the post-transaction scale.
+    auto const& afterVault = afterVault_[0];
+    auto const& vaultAsset = afterVault.asset;
+    if (rules.enabled(fixCleanup3_2_0))
+    {
+        NumberRoundModeGuard const roundGuard(Number::RoundingMode::ToNearest);
+        return scale(afterVault.assetsTotal, vaultAsset);
+    }
+
+    auto const& beforeVault = beforeVault_[0];
+    auto const totalDelta =
+        DeltaInfo::makeDelta(beforeVault.assetsTotal, afterVault.assetsTotal, vaultAsset);
+    auto const availableDelta =
+        DeltaInfo::makeDelta(beforeVault.assetsAvailable, afterVault.assetsAvailable, vaultAsset);
+    return computeCoarsestScale({vaultDelta, totalDelta, availableDelta});
+}
+
+}  // namespace xrpl

src/libxrpl/tx/transactors/vault/VaultClawback.cpp

@@ -25,6 +25,7 @@
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/XRPAmount.h>
 #include <xrpl/tx/Transactor.h>
+#include <xrpl/tx/invariants/VaultInvariantData.h>
 
 #include <optional>
 #include <stdexcept>
@@ -451,20 +452,168 @@ VaultClawback::doApply()
 }
 
 void
-VaultClawback::visitInvariantEntry(bool, SLE::const_ref, SLE::const_ref)
+VaultClawback::visitInvariantEntry(bool isDelete, SLE::const_ref before, SLE::const_ref after)
 {
-    // No transaction-specific invariants yet (future work).
+    data_.visitEntry(isDelete, before, after);
 }
 
 bool
 VaultClawback::finalizeInvariants(
-    STTx const&,
-    TER,
+    STTx const& tx,
+    TER result,
     XRPAmount,
-    ReadView const&,
-    beast::Journal const&)
+    ReadView const& view,
+    beast::Journal const& j)
 {
-    // No transaction-specific invariants yet (future work).
+    static constexpr Number kZero{};
+    bool const enforce = view.rules().enabled(featureSingleAssetVault);
+
+    if (!isTesSuccess(result))
+        return true;  // Do not perform checks
+
+    auto const& afterVaults = data_.afterVaults();
+    if (afterVaults.empty())
+        return true;
+
+    auto const& afterVault = afterVaults[0];
+    auto const& vaultAsset = afterVault.asset;
+
+    auto const& beforeVaults = data_.beforeVaults();
+    XRPL_ASSERT(
+        !beforeVaults.empty(),
+        "xrpl::VaultClawback::finalizeInvariants : clawback updated a vault");
+    auto const& beforeVault = beforeVaults[0];
+
+    // Retrieve the before-shares for this vault (from beforeMPTs_).
+    auto const beforeShares = [&]() -> std::optional<VaultInvariantData::Shares> {
+        for (auto const& e : data_.beforeMPTIssuances())
+        {
+            if (e.share.getMptID() == beforeVault.shareMPTID)
+                return e;
+        }
+        return std::nullopt;
+    }();
+
+    auto const isVaultEmpty = [](VaultInvariantData::Vault const& v) -> bool {
+        return v.assetsAvailable == Number{} && v.assetsTotal == Number{};
+    };
+
+    // Check 1: clawback is either by the asset issuer, OR by the vault owner
+    // on an empty vault (force-burn of lingering shares).
+    if (vaultAsset.native() || vaultAsset.getIssuer() != tx[sfAccount])
+    {
+        if (!(beforeShares && beforeShares->sharesTotal > 0 && isVaultEmpty(beforeVault) &&
+              beforeVault.owner == tx[sfAccount]))
+        {
+            JLOG(j.fatal())
+                << "Invariant failed: "  //
+                << "clawback may only be performed by the asset issuer, or by the vault "
+                << "owner of an empty vault";
+            XRPL_ASSERT(
+                enforce,
+                "xrpl::VaultClawback::finalizeInvariants : clawback issuer or empty vault owner");
+            return !enforce;  // That's all we can do
+        }
+    }
+
+    bool checkResult = true;
+
+    auto const maybeVaultDeltaAssets = data_.deltaAssets(afterVault.pseudoId);
+    if (maybeVaultDeltaAssets)
+    {
+        auto const minScale = data_.computeVaultMinScale(*maybeVaultDeltaAssets, view.rules());
+        auto const vaultDeltaAssets =
+            roundToAsset(vaultAsset, maybeVaultDeltaAssets->delta, minScale);
+
+        // Check 2: vault balance decreased.
+        if (vaultDeltaAssets >= kZero)
+        {
+            JLOG(j.fatal()) << "Invariant failed: clawback must decrease vault balance";
+            checkResult = false;
+        }
+
+        // Check 3: assetsTotal changed by vaultDelta.
+        auto const assetsTotalDelta =
+            roundToAsset(vaultAsset, afterVault.assetsTotal - beforeVault.assetsTotal, minScale);
+        if (assetsTotalDelta != vaultDeltaAssets)
+        {
+            JLOG(j.fatal()) <<  //
+                "Invariant failed: clawback and assets outstanding must add up";
+            checkResult = false;
+        }
+
+        // Check 4: assetsAvailable changed by vaultDelta.
+        auto const assetAvailableDelta = roundToAsset(
+            vaultAsset, afterVault.assetsAvailable - beforeVault.assetsAvailable, minScale);
+        if (assetAvailableDelta != vaultDeltaAssets)
+        {
+            JLOG(j.fatal()) <<  //
+                "Invariant failed: clawback and assets available must add up";
+            checkResult = false;
+        }
+    }
+    else if (!isVaultEmpty(beforeVault))
+    {
+        JLOG(j.fatal()) <<  //
+            "Invariant failed: clawback must change vault balance";
+        XRPL_ASSERT(
+            enforce, "xrpl::VaultClawback::finalizeInvariants : clawback vault balance invariant");
+        return !enforce;  // That's all we can do
+    }
+
+    // Check 5: holder shares (tx[sfHolder]) decreased.
+    // We don't need to round shares, they are integral MPT.
+    auto const maybeAccountDeltaShares = data_.deltaShares(tx[sfHolder]);
+    if (!maybeAccountDeltaShares)
+    {
+        JLOG(j.fatal()) <<  //
+            "Invariant failed: clawback must change holder shares";
+        XRPL_ASSERT(
+            enforce, "xrpl::VaultClawback::finalizeInvariants : clawback holder shares invariant");
+        if (!checkResult)
+        {
+            XRPL_ASSERT(
+                enforce, "xrpl::VaultClawback::finalizeInvariants : vault clawback invariants");
+        }
+        return !enforce;  // That's all we can do
+    }
+    if (maybeAccountDeltaShares->delta >= kZero)
+    {
+        JLOG(j.fatal()) <<  //
+            "Invariant failed: clawback must decrease holder shares";
+        checkResult = false;
+    }
+
+    // Check 6: vault shares (outstanding) changed by same amount as holder decrease.
+    // We don't need to round shares, they are integral MPT.
+    auto const vaultDeltaShares = data_.deltaShares(afterVault.pseudoId);
+    if (!vaultDeltaShares || vaultDeltaShares->delta == kZero)
+    {
+        JLOG(j.fatal()) <<  //
+            "Invariant failed: clawback must change vault shares";
+        XRPL_ASSERT(
+            enforce, "xrpl::VaultClawback::finalizeInvariants : clawback vault shares invariant");
+        if (!checkResult)
+        {
+            XRPL_ASSERT(
+                enforce, "xrpl::VaultClawback::finalizeInvariants : vault clawback invariants");
+        }
+        return !enforce;  // That's all we can do
+    }
+
+    if (vaultDeltaShares->delta * -1 != maybeAccountDeltaShares->delta)
+    {
+        JLOG(j.fatal()) << "Invariant failed: "  //
+                        << "clawback must change holder and vault shares by equal amount";
+        checkResult = false;
+    }
+
+    if (!checkResult)
+    {
+        XRPL_ASSERT(enforce, "xrpl::VaultClawback::finalizeInvariants : vault clawback invariants");
+        return !enforce;
+    }
+
     return true;
 }
 

src/libxrpl/tx/transactors/vault/VaultCreate.cpp

@@ -1,8 +1,10 @@
 #include <xrpl/tx/transactors/vault/VaultCreate.h>
 
+#include <xrpl/basics/Log.h>
 #include <xrpl/basics/Number.h>
 #include <xrpl/basics/base_uint.h>
 #include <xrpl/beast/utility/Zero.h>
+#include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/ledger/View.h>
 #include <xrpl/ledger/helpers/AccountRootHelpers.h>
@@ -263,15 +265,107 @@ VaultCreate::doApply()
 }
 
 void
-VaultCreate::visitInvariantEntry(bool, SLE::const_ref, SLE::const_ref)
+VaultCreate::visitInvariantEntry(bool isDelete, SLE::const_ref before, SLE::const_ref after)
 {
-    // No transaction-specific invariants yet (future work).
+    data_.visitEntry(isDelete, before, after);
 }
 
 bool
-VaultCreate::finalizeInvariants(STTx const&, TER, XRPAmount, ReadView const&, beast::Journal const&)
+VaultCreate::finalizeInvariants(
+    STTx const&,
+    TER result,
+    XRPAmount,
+    ReadView const& view,
+    beast::Journal const& j)
 {
-    // No transaction-specific invariants yet (future work).
+    bool const enforce = view.rules().enabled(featureSingleAssetVault);
+
+    if (!isTesSuccess(result))
+        return true;
+
+    auto const& afterVaults = data_.afterVaults();
+    if (afterVaults.empty())
+        return true;
+
+    auto const& afterVault = afterVaults[0];
+    bool checkResult = true;
+
+    if (!data_.beforeVaults().empty())
+    {
+        JLOG(j.fatal()) << "Invariant failed: create operation must not have updated a vault";
+        checkResult = false;
+    }
+
+    // The MPTokenIssuance may not be in the modified set (e.g. only the vault
+    // was touched in the test), so fall back to a view read if needed.
+    auto const updatedShares = [&]() -> std::optional<VaultInvariantData::Shares> {
+        if (auto found = data_.findShares(afterVault.shareMPTID))
+            return found;
+        auto const sleShares = view.read(keylet::mptIssuance(afterVault.shareMPTID));
+        return sleShares ? std::optional<VaultInvariantData::Shares>(
+                               VaultInvariantData::Shares::make(*sleShares))
+                         : std::nullopt;
+    }();
+
+    static constexpr Number kZero{};
+
+    if (afterVault.assetsAvailable != kZero || afterVault.assetsTotal != kZero ||
+        afterVault.lossUnrealized != kZero || (updatedShares && updatedShares->sharesTotal != 0))
+    {
+        JLOG(j.fatal()) << "Invariant failed: created vault must be empty";
+        checkResult = false;
+    }
+
+    if (!updatedShares)
+    {
+        JLOG(j.fatal()) << "Invariant failed: updated vault must have shares";
+        XRPL_ASSERT(enforce, "xrpl::VaultCreate::finalizeInvariants : vault has shares invariant");
+        if (!checkResult)
+        {
+            XRPL_ASSERT(enforce, "xrpl::VaultCreate::finalizeInvariants : vault create invariants");
+        }
+        return !enforce;
+    }
+
+    if (afterVault.pseudoId != updatedShares->share.getIssuer())
+    {
+        JLOG(j.fatal())
+            << "Invariant failed: shares issuer and vault pseudo-account must be the same";
+        checkResult = false;
+    }
+
+    auto const sleSharesIssuer = view.read(keylet::account(updatedShares->share.getIssuer()));
+    if (!sleSharesIssuer)
+    {
+        JLOG(j.fatal()) << "Invariant failed: shares issuer must exist";
+        XRPL_ASSERT(
+            enforce, "xrpl::VaultCreate::finalizeInvariants : shares issuer exists invariant");
+        if (!checkResult)
+        {
+            XRPL_ASSERT(enforce, "xrpl::VaultCreate::finalizeInvariants : vault create invariants");
+        }
+        return !enforce;
+    }
+
+    if (!isPseudoAccount(sleSharesIssuer))
+    {
+        JLOG(j.fatal()) << "Invariant failed: shares issuer must be a pseudo-account";
+        checkResult = false;
+    }
+
+    if (auto const vaultId = (*sleSharesIssuer)[~sfVaultID]; !vaultId || *vaultId != afterVault.key)
+    {
+        JLOG(j.fatal())
+            << "Invariant failed: shares issuer pseudo-account must point back to the vault";
+        checkResult = false;
+    }
+
+    if (!checkResult)
+    {
+        XRPL_ASSERT(enforce, "xrpl::VaultCreate::finalizeInvariants : vault create invariants");
+        return !enforce;
+    }
+
     return true;
 }