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.github/scripts/levelization/results/ordering.txt

@@ -42,6 +42,7 @@ libxrpl.tx > xrpl.server
 libxrpl.tx > xrpl.tx
 test.app > test.jtx
 test.app > test.rpc
+test.app > test.shamap
 test.app > test.toplevel
 test.app > test.unit_test
 test.app > xrpl.basics
@@ -57,6 +58,7 @@ test.app > xrpl.protocol
 test.app > xrpl.rdb
 test.app > xrpl.resource
 test.app > xrpl.server
+test.app > xrpl.shamap
 test.app > xrpl.tx
 test.basics > test.jtx
 test.basics > test.unit_test

include/xrpl/basics/Slice.h

@@ -11,6 +11,7 @@
 #include <limits>
 #include <stdexcept>
 #include <string>
+#include <string_view>
 #include <type_traits>
 #include <vector>
 
@@ -231,4 +232,11 @@ makeSlice(std::basic_string<char, Traits, Alloc> const& s)
     return Slice(s.data(), s.size());
 }
 
+template <class Traits>
+Slice
+makeSlice(std::basic_string_view<char, Traits> const& s)
+{
+    return Slice(s.data(), s.size());
+}
+
 }  // namespace xrpl

include/xrpl/proto/xrpl.proto

@@ -244,7 +244,15 @@ message TMGetObjectByHash {
 
 message TMLedgerNode {
   required bytes nodedata = 1;
-  optional bytes nodeid = 2;  // missing for ledger base data
+
+  // Used when protocol version <2.3. Not set for ledger base data.
+  optional bytes nodeid = 2;
+
+  // Used when protocol version >=2.3. Neither value is set for ledger base data.
+  oneof reference {
+    bytes id = 3;      // Set for inner nodes.
+    uint32 depth = 4;  // Set for leaf nodes.
+  }
 }
 
 enum TMLedgerInfoType {

include/xrpl/shamap/SHAMap.h

@@ -16,6 +16,7 @@
 
 #include <set>
 #include <stack>
+#include <tuple>
 #include <vector>
 
 namespace xrpl {
@@ -253,7 +254,7 @@ public:
     bool
     getNodeFat(
         SHAMapNodeID const& wanted,
-        std::vector<std::pair<SHAMapNodeID, Blob>>& data,
+        std::vector<std::tuple<SHAMapNodeID, Blob, bool>>& data,
         bool fatLeaves,
         std::uint32_t depth) const;
 
@@ -280,10 +281,45 @@ public:
     void
     serializeRoot(Serializer& s) const;
 
+    /** Add a root node to the SHAMap during synchronization.
+     *
+     * This function is used when receiving the root node of a SHAMap from a peer during ledger
+     * synchronization. The node must already have been deserialized.
+     *
+     * @param hash The expected hash of the root node.
+     * @param rootNode A deserialized root node to add.
+     * @param filter Optional sync filter to track received nodes.
+     * @return Status indicating whether the node was useful, duplicate, or invalid.
+     *
+     * @note This function expects the rootNode to be a valid, deserialized SHAMapTreeNode. The
+     *       caller is responsible for deserialization and basic validation before calling this
+     *       function.
+     */
     SHAMapAddNode
-    addRootNode(SHAMapHash const& hash, Slice const& rootNode, SHAMapSyncFilter* filter);
+    addRootNode(
+        SHAMapHash const& hash,
+        intr_ptr::SharedPtr<SHAMapTreeNode> rootNode,
+        SHAMapSyncFilter const* filter);
+
+    /** Add a known node at a specific position in the SHAMap during synchronization.
+     *
+     * This function is used when receiving nodes from peers during ledger synchronization. The node
+     * is inserted at the position specified by nodeID. The node must already have been
+     * deserialized.
+     *
+     * @param nodeID The position in the tree where this node belongs.
+     * @param treeNode A deserialized tree node to add.
+     * @param filter Optional sync filter to track received nodes.
+     * @return Status indicating whether the node was useful, duplicate, or invalid.
+     *
+     * @note This function expects that the caller has already validated that the nodeID is
+     * consistent with the node's content.
+     */
     SHAMapAddNode
-    addKnownNode(SHAMapNodeID const& nodeID, Slice const& rawNode, SHAMapSyncFilter* filter);
+    addKnownNode(
+        SHAMapNodeID const& nodeID,
+        intr_ptr::SharedPtr<SHAMapTreeNode> treeNode,
+        SHAMapSyncFilter const* filter);
 
     // status functions
     void
@@ -344,11 +380,11 @@ private:
     intr_ptr::SharedPtr<SHAMapTreeNode>
     fetchNodeNT(SHAMapHash const& hash) const;
     intr_ptr::SharedPtr<SHAMapTreeNode>
-    fetchNodeNT(SHAMapHash const& hash, SHAMapSyncFilter* filter) const;
+    fetchNodeNT(SHAMapHash const& hash, SHAMapSyncFilter const* filter) const;
     intr_ptr::SharedPtr<SHAMapTreeNode>
     fetchNode(SHAMapHash const& hash) const;
     intr_ptr::SharedPtr<SHAMapTreeNode>
-    checkFilter(SHAMapHash const& hash, SHAMapSyncFilter* filter) const;
+    checkFilter(SHAMapHash const& hash, SHAMapSyncFilter const* filter) const;
 
     /** Update hashes up to the root */
     void
@@ -420,7 +456,7 @@ private:
     descendAsync(
         SHAMapInnerNode* parent,
         int branch,
-        SHAMapSyncFilter* filter,
+        SHAMapSyncFilter const* filter,
         bool& pending,
         descendCallback&&) const;
 
@@ -429,7 +465,7 @@ private:
         SHAMapInnerNode* parent,
         SHAMapNodeID const& parentID,
         int branch,
-        SHAMapSyncFilter* filter) const;
+        SHAMapSyncFilter const* filter) const;
 
     // Non-storing
     // Does not hook the returned node to its parent

src/libxrpl/shamap/SHAMap.cpp

@@ -178,7 +178,7 @@ SHAMap::finishFetch(SHAMapHash const& hash, std::shared_ptr<NodeObject> const& o
 
 // See if a sync filter has a node
 intr_ptr::SharedPtr<SHAMapTreeNode>
-SHAMap::checkFilter(SHAMapHash const& hash, SHAMapSyncFilter* filter) const
+SHAMap::checkFilter(SHAMapHash const& hash, SHAMapSyncFilter const* filter) const
 {
     if (auto nodeData = filter->getNode(hash))
     {
@@ -204,7 +204,7 @@ SHAMap::checkFilter(SHAMapHash const& hash, SHAMapSyncFilter* filter) const
 // Get a node without throwing
 // Used on maps where missing nodes are expected
 intr_ptr::SharedPtr<SHAMapTreeNode>
-SHAMap::fetchNodeNT(SHAMapHash const& hash, SHAMapSyncFilter* filter) const
+SHAMap::fetchNodeNT(SHAMapHash const& hash, SHAMapSyncFilter const* filter) const
 {
     auto node = cacheLookup(hash);
     if (node)
@@ -317,7 +317,7 @@ SHAMap::descend(
     SHAMapInnerNode* parent,
     SHAMapNodeID const& parentID,
     int branch,
-    SHAMapSyncFilter* filter) const
+    SHAMapSyncFilter const* filter) const
 {
     XRPL_ASSERT(parent->isInner(), "xrpl::SHAMap::descend : valid parent input");
     XRPL_ASSERT(
@@ -346,7 +346,7 @@ SHAMapTreeNode*
 SHAMap::descendAsync(
     SHAMapInnerNode* parent,
     int branch,
-    SHAMapSyncFilter* filter,
+    SHAMapSyncFilter const* filter,
     bool& pending,
     descendCallback&& callback) const
 {

src/libxrpl/shamap/SHAMapNodeID.cpp

@@ -118,7 +118,9 @@ selectBranch(SHAMapNodeID const& id, uint256 const& hash)
 SHAMapNodeID
 SHAMapNodeID::createID(int depth, uint256 const& key)
 {
-    XRPL_ASSERT((depth >= 0) && (depth < 65), "xrpl::SHAMapNodeID::createID : valid branch input");
+    XRPL_ASSERT(
+        depth >= 0 && depth <= SHAMap::leafDepth,
+        "xrpl::SHAMapNodeID::createID : valid branch input");
     return SHAMapNodeID(depth, key & depthMask(depth));
 }
 

src/libxrpl/shamap/SHAMapSync.cpp

@@ -386,7 +386,7 @@ SHAMap::getMissingNodes(int max, SHAMapSyncFilter* filter)
 bool
 SHAMap::getNodeFat(
     SHAMapNodeID const& wanted,
-    std::vector<std::pair<SHAMapNodeID, Blob>>& data,
+    std::vector<std::tuple<SHAMapNodeID, Blob, bool>>& data,
     bool fatLeaves,
     std::uint32_t depth) const
 {
@@ -432,7 +432,7 @@ SHAMap::getNodeFat(
         // Add this node to the reply
         s.erase();
         node->serializeForWire(s);
-        data.emplace_back(std::make_pair(nodeID, s.getData()));
+        data.emplace_back(std::make_tuple(nodeID, s.getData(), node->isLeaf()));
 
         if (node->isInner())
         {
@@ -462,7 +462,8 @@ SHAMap::getNodeFat(
                             // Just include this node
                             s.erase();
                             childNode->serializeForWire(s);
-                            data.emplace_back(std::make_pair(childID, s.getData()));
+                            data.emplace_back(
+                                std::make_tuple(childID, s.getData(), childNode->isLeaf()));
                         }
                     }
                 }
@@ -480,8 +481,18 @@ SHAMap::serializeRoot(Serializer& s) const
 }
 
 SHAMapAddNode
-SHAMap::addRootNode(SHAMapHash const& hash, Slice const& rootNode, SHAMapSyncFilter* filter)
+SHAMap::addRootNode(
+    SHAMapHash const& hash,
+    intr_ptr::SharedPtr<SHAMapTreeNode> rootNode,
+    SHAMapSyncFilter const* filter)
 {
+    XRPL_ASSERT(rootNode, "xrpl::SHAMap::addRootNode : non-null root node");
+    if (!rootNode)
+    {
+        JLOG(journal_.error()) << "Null node received";
+        return SHAMapAddNode::invalid();
+    }
+
     // we already have a root_ node
     if (root_->getHash().isNonZero())
     {
@@ -491,14 +502,16 @@ SHAMap::addRootNode(SHAMapHash const& hash, Slice const& rootNode, SHAMapSyncFil
     }
 
     XRPL_ASSERT(cowid_ >= 1, "xrpl::SHAMap::addRootNode : valid cowid");
-    auto node = SHAMapTreeNode::makeFromWire(rootNode);
-    if (!node || node->getHash() != hash)
+    if (rootNode->getHash() != hash)
+    {
+        JLOG(journal_.warn()) << "Corrupt node received";
         return SHAMapAddNode::invalid();
+    }
 
     if (backed_)
-        canonicalize(hash, node);
+        canonicalize(hash, rootNode);
 
-    root_ = node;
+    root_ = std::move(rootNode);
 
     if (root_->isLeaf())
         clearSynching();
@@ -515,9 +528,18 @@ SHAMap::addRootNode(SHAMapHash const& hash, Slice const& rootNode, SHAMapSyncFil
 }
 
 SHAMapAddNode
-SHAMap::addKnownNode(SHAMapNodeID const& node, Slice const& rawNode, SHAMapSyncFilter* filter)
+SHAMap::addKnownNode(
+    SHAMapNodeID const& nodeID,
+    intr_ptr::SharedPtr<SHAMapTreeNode> treeNode,
+    SHAMapSyncFilter const* filter)
 {
-    XRPL_ASSERT(!node.isRoot(), "xrpl::SHAMap::addKnownNode : valid node input");
+    XRPL_ASSERT(!nodeID.isRoot(), "xrpl::SHAMap::addKnownNode : valid node input");
+    XRPL_ASSERT(treeNode, "xrpl::SHAMap::addKnownNode : non-null tree node");
+    if (!treeNode)
+    {
+        JLOG(journal_.error()) << "Null node received";
+        return SHAMapAddNode::invalid();
+    }
 
     if (!isSynching())
     {
@@ -531,14 +553,14 @@ SHAMap::addKnownNode(SHAMapNodeID const& node, Slice const& rawNode, SHAMapSyncF
 
     while (currNode->isInner() &&
            !static_cast<SHAMapInnerNode*>(currNode)->isFullBelow(generation) &&
-           (currNodeID.getDepth() < node.getDepth()))
+           (currNodeID.getDepth() < nodeID.getDepth()))
     {
-        int const branch = selectBranch(currNodeID, node.getNodeID());
+        int const branch = selectBranch(currNodeID, nodeID.getNodeID());
         XRPL_ASSERT(branch >= 0, "xrpl::SHAMap::addKnownNode : valid branch");
         auto inner = static_cast<SHAMapInnerNode*>(currNode);
         if (inner->isEmptyBranch(branch))
         {
-            JLOG(journal_.warn()) << "Add known node for empty branch" << node;
+            JLOG(journal_.warn()) << "Add known node for empty branch" << nodeID;
             return SHAMapAddNode::invalid();
         }
 
@@ -554,67 +576,44 @@ SHAMap::addKnownNode(SHAMapNodeID const& node, Slice const& rawNode, SHAMapSyncF
         if (currNode != nullptr)
             continue;
 
-        auto newNode = SHAMapTreeNode::makeFromWire(rawNode);
-
-        if (!newNode || childHash != newNode->getHash())
+        if (childHash != treeNode->getHash())
         {
             JLOG(journal_.warn()) << "Corrupt node received";
             return SHAMapAddNode::invalid();
         }
 
-        // In rare cases, a node can still be corrupt even after hash
-        // validation. For leaf nodes, we perform an additional check to
-        // ensure the node's position in the tree is consistent with its
-        // content to prevent inconsistencies that could
-        // propagate further down the line.
-        if (newNode->isLeaf())
-        {
-            auto const& actualKey =
-                static_cast<SHAMapLeafNode const*>(newNode.get())->peekItem()->key();
-
-            // Validate that this leaf belongs at the target position
-            auto const expectedNodeID = SHAMapNodeID::createID(node.getDepth(), actualKey);
-            if (expectedNodeID.getNodeID() != node.getNodeID())
-            {
-                JLOG(journal_.debug())
-                    << "Leaf node position mismatch: "
-                    << "expected=" << expectedNodeID.getNodeID() << ", actual=" << node.getNodeID();
-                return SHAMapAddNode::invalid();
-            }
-        }
-
         // Inner nodes must be at a level strictly less than 64
         // but leaf nodes (while notionally at level 64) can be
         // at any depth up to and including 64:
         if ((currNodeID.getDepth() > leafDepth) ||
-            (newNode->isInner() && currNodeID.getDepth() == leafDepth))
+            (treeNode->isInner() && currNodeID.getDepth() == leafDepth))
         {
             // Map is provably invalid
             state_ = SHAMapState::Invalid;
             return SHAMapAddNode::useful();
         }
 
-        if (currNodeID != node)
+        if (currNodeID != nodeID)
         {
             // Either this node is broken or we didn't request it (yet)
-            JLOG(journal_.warn()) << "unable to hook node " << node;
+            JLOG(journal_.warn()) << "unable to hook node " << nodeID;
             JLOG(journal_.info()) << " stuck at " << currNodeID;
-            JLOG(journal_.info()) << "got depth=" << node.getDepth()
+            JLOG(journal_.info()) << "got depth=" << nodeID.getDepth()
                                   << ", walked to= " << currNodeID.getDepth();
             return SHAMapAddNode::useful();
         }
 
         if (backed_)
-            canonicalize(childHash, newNode);
+            canonicalize(childHash, treeNode);
 
-        newNode = prevNode->canonicalizeChild(branch, std::move(newNode));
+        treeNode = prevNode->canonicalizeChild(branch, std::move(treeNode));
 
         if (filter)
         {
             Serializer s;
-            newNode->serializeWithPrefix(s);
+            treeNode->serializeWithPrefix(s);
             filter->gotNode(
-                false, childHash, ledgerSeq_, std::move(s.modData()), newNode->getType());
+                false, childHash, ledgerSeq_, std::move(s.modData()), treeNode->getType());
         }
 
         return SHAMapAddNode::useful();

src/test/app/LedgerNodeHelpers_test.cpp

@@ -0,0 +1,358 @@
+#include <test/shamap/common.h>
+
+#include <xrpld/app/ledger/detail/LedgerNodeHelpers.h>
+
+#include <xrpl/beast/unit_test.h>
+#include <xrpl/protocol/messages.h>
+#include <xrpl/shamap/SHAMap.h>
+#include <xrpl/shamap/SHAMapAccountStateLeafNode.h>
+#include <xrpl/shamap/SHAMapInnerNode.h>
+#include <xrpl/shamap/SHAMapItem.h>
+#include <xrpl/shamap/SHAMapTreeNode.h>
+
+#include <bit>
+
+namespace xrpl {
+namespace tests {
+
+class LedgerNodeHelpers_test : public beast::unit_test::suite
+{
+    // Helper function to create a simple SHAMapItem for testing.
+    static boost::intrusive_ptr<SHAMapItem>
+    makeTestItem(std::uint32_t seed)
+    {
+        Serializer s;
+        s.add32(seed);
+        s.add32(seed + 1);
+        s.add32(seed + 2);
+        return make_shamapitem(s.getSHA512Half(), s.slice());
+    }
+
+    // Helper function to serialize a tree node to wire format.
+    static std::string
+    serializeNode(intr_ptr::SharedPtr<SHAMapTreeNode> const& node)
+    {
+        Serializer s;
+        node->serializeForWire(s);
+        auto const slice = s.slice();
+        return std::string(std::bit_cast<char const*>(slice.data()), slice.size());
+    }
+
+    void
+    testValidateLedgerNode()
+    {
+        // In the tests below the validity of the content of the node data and ID fields is not
+        // checked - only that the fields have values when expected. The content of the fields is
+        // verified in the other tests in this file.
+        testcase("validateLedgerNode");
+
+        // Invalid: missing all fields.
+        {
+            protocol::TMLedgerNode node;
+            BEAST_EXPECT(!validateLedgerNode(node));
+        }
+
+        // Invalid: missing `nodedata` field.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodeid("test_nodeid");
+            BEAST_EXPECT(!validateLedgerNode(node));
+        }
+
+        // Invalid: missing `nodedata` field.
+        {
+            protocol::TMLedgerNode node;
+            node.set_id("test_nodeid");
+            BEAST_EXPECT(!validateLedgerNode(node));
+        }
+
+        // Invalid: missing `nodedata` field.
+        {
+            protocol::TMLedgerNode node;
+            node.set_depth(1);
+            BEAST_EXPECT(!validateLedgerNode(node));
+        }
+
+        // Valid: legacy `nodeid` field.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_nodeid("test_nodeid");
+            BEAST_EXPECT(validateLedgerNode(node));
+        }
+
+        // Invalid: has both legacy `nodeid` and new `id` fields.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_nodeid("test_nodeid");
+            node.set_id("test_nodeid");
+            BEAST_EXPECT(!validateLedgerNode(node));
+        }
+
+        // Invalid: has both legacy `nodeid` and new `depth` fields.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_nodeid("test_nodeid");
+            node.set_depth(5);
+            BEAST_EXPECT(!validateLedgerNode(node));
+        }
+
+        // Valid: new `id` field.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_id("test_id");
+            BEAST_EXPECT(validateLedgerNode(node));
+        }
+
+        // Valid: new `depth` field.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_depth(5);
+            BEAST_EXPECT(validateLedgerNode(node));
+        }
+
+        // Valid: `depth` at minimum depth.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_depth(0);
+            BEAST_EXPECT(validateLedgerNode(node));
+        }
+
+        // Valid: `depth` at arbitrary depth between minimum and maximum.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_depth(10);
+            BEAST_EXPECT(validateLedgerNode(node));
+        }
+
+        // Valid: `depth` at maximum depth.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_depth(SHAMap::leafDepth);
+            BEAST_EXPECT(validateLedgerNode(node));
+        }
+
+        // Invalid: `depth` is greater than maximum depth.
+        {
+            protocol::TMLedgerNode node;
+            node.set_nodedata("test_data");
+            node.set_depth(SHAMap::leafDepth + 1);
+            BEAST_EXPECT(!validateLedgerNode(node));
+        }
+    }
+
+    void
+    testGetTreeNode()
+    {
+        testcase("getTreeNode");
+
+        // Valid: inner node. It must have at least one child for `serializeNode` to work.
+        {
+            auto const innerNode = intr_ptr::make_shared<SHAMapInnerNode>(1);
+            auto const childNode = intr_ptr::make_shared<SHAMapInnerNode>(1);
+            innerNode->setChild(0, childNode);
+            auto const innerData = serializeNode(innerNode);
+            auto const result = getTreeNode(innerData);
+            BEAST_EXPECT(result.has_value());
+            BEAST_EXPECT((*result)->isInner());
+        }
+
+        // Valid: leaf node.
+        {
+            auto const leafItem = makeTestItem(12345);
+            auto const leafNode =
+                intr_ptr::make_shared<SHAMapAccountStateLeafNode>(std::move(leafItem), 1);
+            auto const leafData = serializeNode(leafNode);
+            auto result = getTreeNode(leafData);
+            BEAST_EXPECT(result.has_value());
+            BEAST_EXPECT((*result)->isLeaf());
+        }
+
+        // Invalid: empty data.
+        {
+            auto const result = getTreeNode("");
+            BEAST_EXPECT(!result.has_value());
+        }
+
+        // Invalid: garbage data.
+        {
+            auto const result = getTreeNode("invalid");
+            BEAST_EXPECT(!result.has_value());
+        }
+
+        // Invalid: truncated data.
+        {
+            auto const leafItem = makeTestItem(54321);
+            auto const leafNode =
+                intr_ptr::make_shared<SHAMapAccountStateLeafNode>(std::move(leafItem), 1);
+            // Truncate the data to trigger an exception in SHAMapTreeNode::makeAccountState when
+            // the data is used to deserialize the node.
+            uint256 tag;
+            auto const leafData = serializeNode(leafNode).substr(0, tag.bytes - 1);
+            auto const result = getTreeNode(leafData);
+            BEAST_EXPECT(!result.has_value());
+        }
+    }
+
+    void
+    testGetSHAMapNodeID()
+    {
+        testcase("getSHAMapNodeID");
+
+        {
+            // Tests using inner nodes at various depths.
+            auto const innerNode = intr_ptr::make_shared<SHAMapInnerNode>(1);
+            auto const childNode = intr_ptr::make_shared<SHAMapInnerNode>(1);
+            innerNode->setChild(0, childNode);
+            auto const innerData = serializeNode(innerNode);
+
+            // Valid: legacy `nodeid` field at arbitrary depth.
+            {
+                auto const innerDepth = 3;
+                auto const innerID = SHAMapNodeID::createID(innerDepth, uint256{});
+
+                protocol::TMLedgerNode node;
+                node.set_nodedata(innerData);
+                node.set_nodeid(innerID.getRawString());
+                auto const result = getSHAMapNodeID(node, innerNode);
+                BEAST_EXPECT(result.has_value());
+                BEAST_EXPECT(*result == innerID);
+            }
+
+            // Valid: new `id` field at minimum depth.
+            {
+                auto const innerDepth = 0;
+                auto const innerID = SHAMapNodeID::createID(innerDepth, uint256{});
+
+                protocol::TMLedgerNode node;
+                node.set_nodedata(innerData);
+                node.set_id(innerID.getRawString());
+                auto const result = getSHAMapNodeID(node, innerNode);
+                BEAST_EXPECT(result.has_value());
+                BEAST_EXPECT(*result == innerID);
+            }
+
+            // Invalid: new `depth` field should not be used for inner nodes.
+            {
+                protocol::TMLedgerNode node;
+                node.set_nodedata(innerData);
+                node.set_depth(10);
+                auto const result = getSHAMapNodeID(node, innerNode);
+                BEAST_EXPECT(!result.has_value());
+            }
+        }
+
+        {
+            // Tests using leaf nodes at various depths.
+            auto const leafItem = makeTestItem(12345);
+            auto const leafNode = intr_ptr::make_shared<SHAMapAccountStateLeafNode>(leafItem, 1);
+            auto const leafData = serializeNode(leafNode);
+            auto const leafKey = leafItem->key();
+
+            // Valid: legacy `nodeid` field at arbitrary depth.
+            {
+                auto const leafDepth = 5;
+                auto const leafID = SHAMapNodeID::createID(leafDepth, leafKey);
+
+                protocol::TMLedgerNode ledgerNode;
+                ledgerNode.set_nodedata(leafData);
+                ledgerNode.set_nodeid(leafID.getRawString());
+                auto result = getSHAMapNodeID(ledgerNode, leafNode);
+                BEAST_EXPECT(result.has_value());
+                BEAST_EXPECT(*result == leafID);
+            }
+
+            // Invalid: new `id` field should not be used for leaf nodes.
+            {
+                auto const leafDepth = 5;
+                auto const leafID = SHAMapNodeID::createID(leafDepth, leafKey);
+
+                protocol::TMLedgerNode ledgerNode;
+                ledgerNode.set_nodedata(leafData);
+                ledgerNode.set_id(leafID.getRawString());
+                auto result = getSHAMapNodeID(ledgerNode, leafNode);
+                BEAST_EXPECT(!result.has_value());
+            }
+
+            // Valid: new `depth` field at minimum depth.
+            {
+                auto const leafDepth = 0;
+                auto const leafID = SHAMapNodeID::createID(leafDepth, leafKey);
+
+                protocol::TMLedgerNode node;
+                node.set_nodedata(leafData);
+                node.set_depth(leafDepth);
+                auto result = getSHAMapNodeID(node, leafNode);
+                BEAST_EXPECT(result.has_value());
+                BEAST_EXPECT(*result == leafID);
+            }
+
+            // Valid: new `depth` field at arbitrary depth between minimum and maximum.
+            {
+                auto const leafDepth = 10;
+                auto const leafID = SHAMapNodeID::createID(leafDepth, leafKey);
+
+                protocol::TMLedgerNode ledgerNode;
+                ledgerNode.set_nodedata(leafData);
+                ledgerNode.set_depth(leafDepth);
+                auto result = getSHAMapNodeID(ledgerNode, leafNode);
+                BEAST_EXPECT(result.has_value());
+                BEAST_EXPECT(*result == leafID);
+            }
+
+            // Valid: new `depth` field at maximum depth.
+            // Note that we do not test a depth greater than the maximum depth, because the proto
+            // message is assumed to have been validated by the time the getSHAMapNodeID function is
+            // called.
+            {
+                auto const leafDepth = SHAMap::leafDepth;
+                auto const leafID = SHAMapNodeID::createID(leafDepth, leafKey);
+
+                protocol::TMLedgerNode node;
+                node.set_nodedata(leafData);
+                node.set_depth(leafDepth);
+                auto result = getSHAMapNodeID(node, leafNode);
+                BEAST_EXPECT(result.has_value());
+                BEAST_EXPECT(*result == leafID);
+            }
+
+            // Invalid: legacy `nodeid` field where the node ID is inconsistent with the key.
+            {
+                auto const otherItem = makeTestItem(54321);
+                auto const otherNode =
+                    intr_ptr::make_shared<SHAMapAccountStateLeafNode>(otherItem, 1);
+                auto const otherData = serializeNode(otherNode);
+                auto const otherKey = otherItem->key();
+                auto const otherDepth = 1;
+                auto const otherID = SHAMapNodeID::createID(otherDepth, otherKey);
+
+                protocol::TMLedgerNode ledgerNode;
+                ledgerNode.set_nodedata(otherData);
+                ledgerNode.set_nodeid(otherID.getRawString());
+                auto result = getSHAMapNodeID(ledgerNode, leafNode);
+                BEAST_EXPECT(!result.has_value());
+            }
+        }
+    }
+
+public:
+    void
+    run() override
+    {
+        testValidateLedgerNode();
+        testGetTreeNode();
+        testGetSHAMapNodeID();
+    }
+};
+
+BEAST_DEFINE_TESTSUITE(LedgerNodeHelpers, app, xrpl);
+
+}  // namespace tests
+}  // namespace xrpl

src/test/overlay/ProtocolVersion_test.cpp

@@ -66,8 +66,8 @@ public:
                 negotiateProtocolVersion("RTXP/1.2, XRPL/2.0, XRPL/2.1") == make_protocol(2, 1));
             BEAST_EXPECT(negotiateProtocolVersion("XRPL/2.2") == make_protocol(2, 2));
             BEAST_EXPECT(
-                negotiateProtocolVersion("RTXP/1.2, XRPL/2.2, XRPL/2.3, XRPL/999.999") ==
-                make_protocol(2, 2));
+                negotiateProtocolVersion("RTXP/1.2, XRPL/2.3, XRPL/2.4, XRPL/999.999") ==
+                make_protocol(2, 3));
             BEAST_EXPECT(negotiateProtocolVersion("XRPL/999.999, WebSocket/1.0") == std::nullopt);
             BEAST_EXPECT(negotiateProtocolVersion("") == std::nullopt);
         }

src/test/shamap/SHAMapSync_test.cpp

@@ -103,14 +103,17 @@ public:
         destination.setSynching();
 
         {
-            std::vector<std::pair<SHAMapNodeID, Blob>> a;
+            std::vector<std::tuple<SHAMapNodeID, Blob, bool>> a;
 
             BEAST_EXPECT(source.getNodeFat(SHAMapNodeID(), a, rand_bool(eng_), rand_int(eng_, 2)));
 
             unexpected(a.size() < 1, "NodeSize");
 
-            BEAST_EXPECT(destination.addRootNode(source.getHash(), makeSlice(a[0].second), nullptr)
-                             .isGood());
+            auto node = SHAMapTreeNode::makeFromWire(makeSlice(std::get<1>(a[0])));
+            if (!node)
+                fail("", __FILE__, __LINE__);
+            BEAST_EXPECT(
+                destination.addRootNode(source.getHash(), std::move(node), nullptr).isGood());
         }
 
         do
@@ -124,7 +127,7 @@ public:
                 break;
 
             // get as many nodes as possible based on this information
-            std::vector<std::pair<SHAMapNodeID, Blob>> b;
+            std::vector<std::tuple<SHAMapNodeID, Blob, bool>> b;
 
             for (auto& it : nodesMissing)
             {
@@ -146,7 +149,10 @@ public:
                 // Don't use BEAST_EXPECT here b/c it will be called a
                 // non-deterministic number of times and the number of tests run
                 // should be deterministic
-                if (!destination.addKnownNode(b[i].first, makeSlice(b[i].second), nullptr)
+                auto node = SHAMapTreeNode::makeFromWire(makeSlice(std::get<1>(b[i])));
+                if (!node)
+                    fail("", __FILE__, __LINE__);
+                if (!destination.addKnownNode(std::get<0>(b[i]), std::move(node), nullptr)
                          .isUseful())
                     fail("", __FILE__, __LINE__);
             }

src/xrpld/app/ledger/InboundLedger.h

@@ -9,6 +9,7 @@
 
 #include <mutex>
 #include <set>
+#include <string_view>
 #include <utility>
 
 namespace xrpl {
@@ -131,16 +132,16 @@ private:
     processData(std::shared_ptr<Peer> peer, protocol::TMLedgerData& data);
 
     bool
-    takeHeader(std::string const& data);
+    takeHeader(std::string_view data);
 
     void
-    receiveNode(protocol::TMLedgerData& packet, SHAMapAddNode&);
+    receiveNode(protocol::TMLedgerData& packet, SHAMapAddNode& san);
 
     bool
-    takeTxRootNode(Slice const& data, SHAMapAddNode&);
+    takeTxRootNode(std::string_view data, SHAMapAddNode& san);
 
     bool
-    takeAsRootNode(Slice const& data, SHAMapAddNode&);
+    takeAsRootNode(std::string_view data, SHAMapAddNode& san);
 
     std::vector<uint256>
     neededTxHashes(int max, SHAMapSyncFilter* filter) const;

src/xrpld/app/ledger/detail/InboundLedger.cpp

@@ -3,6 +3,7 @@
 #include <xrpld/app/ledger/InboundLedgers.h>
 #include <xrpld/app/ledger/LedgerMaster.h>
 #include <xrpld/app/ledger/TransactionStateSF.h>
+#include <xrpld/app/ledger/detail/LedgerNodeHelpers.h>
 #include <xrpld/app/main/Application.h>
 #include <xrpld/overlay/Overlay.h>
 
@@ -754,7 +755,7 @@ InboundLedger::filterNodes(
 */
 // data must not have hash prefix
 bool
-InboundLedger::takeHeader(std::string const& data)
+InboundLedger::takeHeader(std::string_view data)
 {
     // Return value: true=normal, false=bad data
     JLOG(journal_.trace()) << "got header acquiring ledger " << hash_;
@@ -839,21 +840,28 @@ InboundLedger::receiveNode(protocol::TMLedgerData& packet, SHAMapAddNode& san)
     {
         auto const f = filter.get();
 
-        for (auto const& node : packet.nodes())
+        for (auto const& ledger_node : packet.nodes())
         {
-            auto const nodeID = deserializeSHAMapNodeID(node.nodeid());
+            auto treeNode = getTreeNode(ledger_node.nodedata());
+            if (!treeNode)
+            {
+                JLOG(journal_.warn()) << "Got invalid node data";
+                san.incInvalid();
+                return;
+            }
 
+            auto const nodeID = getSHAMapNodeID(ledger_node, *treeNode);
             if (!nodeID)
-                throw std::runtime_error("data does not properly deserialize");
+            {
+                JLOG(journal_.warn()) << "Got invalid node id";
+                san.incInvalid();
+                return;
+            }
 
             if (nodeID->isRoot())
-            {
-                san += map.addRootNode(rootHash, makeSlice(node.nodedata()), f);
-            }
+                san += map.addRootNode(rootHash, std::move(*treeNode), f);
             else
-            {
-                san += map.addKnownNode(*nodeID, makeSlice(node.nodedata()), f);
-            }
+                san += map.addKnownNode(*nodeID, std::move(*treeNode), f);
 
             if (!san.isGood())
             {
@@ -888,7 +896,7 @@ InboundLedger::receiveNode(protocol::TMLedgerData& packet, SHAMapAddNode& san)
     Call with a lock
 */
 bool
-InboundLedger::takeAsRootNode(Slice const& data, SHAMapAddNode& san)
+InboundLedger::takeAsRootNode(std::string_view data, SHAMapAddNode& san)
 {
     if (failed_ || mHaveState)
     {
@@ -904,9 +912,17 @@ InboundLedger::takeAsRootNode(Slice const& data, SHAMapAddNode& san)
         // LCOV_EXCL_STOP
     }
 
+    auto treeNode = getTreeNode(data);
+    if (!treeNode)
+    {
+        JLOG(journal_.warn()) << "Got invalid node data";
+        san.incInvalid();
+        return false;
+    }
+
     AccountStateSF filter(mLedger->stateMap().family().db(), app_.getLedgerMaster());
-    san +=
-        mLedger->stateMap().addRootNode(SHAMapHash{mLedger->header().accountHash}, data, &filter);
+    san += mLedger->stateMap().addRootNode(
+        SHAMapHash{mLedger->header().accountHash}, std::move(*treeNode), &filter);
     return san.isGood();
 }
 
@@ -914,7 +930,7 @@ InboundLedger::takeAsRootNode(Slice const& data, SHAMapAddNode& san)
     Call with a lock
 */
 bool
-InboundLedger::takeTxRootNode(Slice const& data, SHAMapAddNode& san)
+InboundLedger::takeTxRootNode(std::string_view data, SHAMapAddNode& san)
 {
     if (failed_ || mHaveTransactions)
     {
@@ -930,8 +946,17 @@ InboundLedger::takeTxRootNode(Slice const& data, SHAMapAddNode& san)
         // LCOV_EXCL_STOP
     }
 
+    auto treeNode = getTreeNode(data);
+    if (!treeNode)
+    {
+        JLOG(journal_.warn()) << "Got invalid node data";
+        san.incInvalid();
+        return false;
+    }
+
     TransactionStateSF filter(mLedger->txMap().family().db(), app_.getLedgerMaster());
-    san += mLedger->txMap().addRootNode(SHAMapHash{mLedger->header().txHash}, data, &filter);
+    san += mLedger->txMap().addRootNode(
+        SHAMapHash{mLedger->header().txHash}, std::move(*treeNode), &filter);
     return san.isGood();
 }
 
@@ -1028,13 +1053,13 @@ InboundLedger::processData(std::shared_ptr<Peer> peer, protocol::TMLedgerData& p
             }
 
             if (!mHaveState && (packet.nodes().size() > 1) &&
-                !takeAsRootNode(makeSlice(packet.nodes(1).nodedata()), san))
+                !takeAsRootNode(packet.nodes(1).nodedata(), san))
             {
                 JLOG(journal_.warn()) << "Included AS root invalid";
             }
 
             if (!mHaveTransactions && (packet.nodes().size() > 2) &&
-                !takeTxRootNode(makeSlice(packet.nodes(2).nodedata()), san))
+                !takeTxRootNode(packet.nodes(2).nodedata(), san))
             {
                 JLOG(journal_.warn()) << "Included TX root invalid";
             }
@@ -1067,13 +1092,13 @@ InboundLedger::processData(std::shared_ptr<Peer> peer, protocol::TMLedgerData& p
 
         ScopedLockType sl(mtx_);
 
-        // Verify node IDs and data are complete
-        for (auto const& node : packet.nodes())
+        // Verify nodes are complete
+        for (auto const& ledger_node : packet.nodes())
         {
-            if (!node.has_nodeid() || !node.has_nodedata())
+            if (!validateLedgerNode(ledger_node))
             {
-                JLOG(journal_.warn()) << "Got bad node";
-                peer->charge(Resource::feeMalformedRequest, "ledger_data bad node");
+                JLOG(journal_.warn()) << "Got malformed ledger node";
+                peer->charge(Resource::feeMalformedRequest, "ledger_node");
                 return -1;
             }
         }

src/xrpld/app/ledger/detail/InboundLedgers.cpp

@@ -1,5 +1,6 @@
 #include <xrpld/app/ledger/InboundLedgers.h>
 #include <xrpld/app/ledger/LedgerMaster.h>
+#include <xrpld/app/ledger/detail/LedgerNodeHelpers.h>
 #include <xrpld/app/main/Application.h>
 
 #include <xrpl/basics/DecayingSample.h>
@@ -222,23 +223,21 @@ public:
         Serializer s;
         try
         {
-            for (int i = 0; i < packet_ptr->nodes().size(); ++i)
+            for (auto const& ledger_node : packet_ptr->nodes())
             {
-                auto const& node = packet_ptr->nodes(i);
-
-                if (!node.has_nodeid() || !node.has_nodedata())
+                if (!validateLedgerNode(ledger_node))
                     return;
 
-                auto newNode = SHAMapTreeNode::makeFromWire(makeSlice(node.nodedata()));
-
-                if (!newNode)
+                auto const treeNode = getTreeNode(ledger_node.nodedata());
+                if (!treeNode)
                     return;
+                auto const tn = *treeNode;
 
                 s.erase();
-                newNode->serializeWithPrefix(s);
+                tn->serializeWithPrefix(s);
 
                 app_.getLedgerMaster().addFetchPack(
-                    newNode->getHash().as_uint256(), std::make_shared<Blob>(s.begin(), s.end()));
+                    tn->getHash().as_uint256(), std::make_shared<Blob>(s.begin(), s.end()));
             }
         }
         catch (std::exception const&)  // NOLINT(bugprone-empty-catch)

src/xrpld/app/ledger/detail/InboundTransactions.cpp

@@ -1,5 +1,6 @@
 #include <xrpld/app/ledger/InboundLedgers.h>
 #include <xrpld/app/ledger/InboundTransactions.h>
+#include <xrpld/app/ledger/detail/LedgerNodeHelpers.h>
 #include <xrpld/app/ledger/detail/TransactionAcquire.h>
 #include <xrpld/app/main/Application.h>
 
@@ -132,29 +133,38 @@ public:
             return;
         }
 
-        std::vector<std::pair<SHAMapNodeID, Slice>> data;
+        std::vector<std::pair<SHAMapNodeID, intr_ptr::SharedPtr<SHAMapTreeNode>>> data;
         data.reserve(packet.nodes().size());
 
-        for (auto const& node : packet.nodes())
+        for (auto const& ledger_node : packet.nodes())
         {
-            if (!node.has_nodeid() || !node.has_nodedata())
+            if (!validateLedgerNode(ledger_node))
             {
-                peer->charge(Resource::feeMalformedRequest, "ledger_data");
+                JLOG(j_.warn()) << "Got malformed ledger node";
+                peer->charge(Resource::feeMalformedRequest, "ledger_node");
                 return;
             }
 
-            auto const id = deserializeSHAMapNodeID(node.nodeid());
-
-            if (!id)
+            auto treeNode = getTreeNode(ledger_node.nodedata());
+            if (!treeNode)
             {
-                peer->charge(Resource::feeInvalidData, "ledger_data");
+                JLOG(j_.warn()) << "Got invalid node data";
+                peer->charge(Resource::feeInvalidData, "node_data");
                 return;
             }
 
-            data.emplace_back(std::make_pair(*id, makeSlice(node.nodedata())));
+            auto const nodeID = getSHAMapNodeID(ledger_node, *treeNode);
+            if (!nodeID)
+            {
+                JLOG(j_.warn()) << "Got invalid node id";
+                peer->charge(Resource::feeInvalidData, "node_id");
+                return;
+            }
+
+            data.emplace_back(std::make_pair(*nodeID, std::move(*treeNode)));
         }
 
-        if (!ta->takeNodes(data, peer).isUseful())
+        if (!ta->takeNodes(std::move(data), peer).isUseful())
             peer->charge(Resource::feeUselessData, "ledger_data not useful");
     }
 

src/xrpld/app/ledger/detail/LedgerNodeHelpers.cpp

@@ -0,0 +1,93 @@
+#include <xrpld/app/ledger/detail/LedgerNodeHelpers.h>
+
+#include <xrpl/basics/IntrusivePointer.h>
+#include <xrpl/basics/Slice.h>
+#include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/protocol/messages.h>
+#include <xrpl/shamap/SHAMap.h>
+#include <xrpl/shamap/SHAMapLeafNode.h>
+#include <xrpl/shamap/SHAMapNodeID.h>
+#include <xrpl/shamap/SHAMapTreeNode.h>
+
+#include <optional>
+#include <string>
+
+namespace xrpl {
+
+bool
+validateLedgerNode(protocol::TMLedgerNode const& ledger_node)
+{
+    if (!ledger_node.has_nodedata())
+        return false;
+
+    if (ledger_node.has_nodeid())
+        return !ledger_node.has_id() && !ledger_node.has_depth();
+
+    return ledger_node.has_id() ||
+        (ledger_node.has_depth() && ledger_node.depth() <= SHAMap::leafDepth);
+}
+
+std::optional<intr_ptr::SharedPtr<SHAMapTreeNode>>
+getTreeNode(std::string_view data)
+{
+    auto const slice = makeSlice(data);
+    try
+    {
+        auto treeNode = SHAMapTreeNode::makeFromWire(slice);
+        if (!treeNode)
+            return std::nullopt;
+        return treeNode;
+    }
+    catch (std::exception const&)
+    {
+        return std::nullopt;
+    }
+}
+
+std::optional<SHAMapNodeID>
+getSHAMapNodeID(
+    protocol::TMLedgerNode const& ledger_node,
+    intr_ptr::SharedPtr<SHAMapTreeNode> const& treeNode)
+{
+    if (ledger_node.has_id() || ledger_node.has_depth())
+    {
+        if (treeNode->isInner())
+        {
+            if (!ledger_node.has_id())
+                return std::nullopt;
+
+            return deserializeSHAMapNodeID(ledger_node.id());
+        }
+
+        if (treeNode->isLeaf())
+        {
+            if (!ledger_node.has_depth())
+                return std::nullopt;
+
+            auto const key = static_cast<SHAMapLeafNode const*>(treeNode.get())->peekItem()->key();
+            return SHAMapNodeID::createID(ledger_node.depth(), key);
+        }
+
+        UNREACHABLE("xrpl::getSHAMapNodeID : tree node is neither inner nor leaf");
+        return std::nullopt;
+    }
+
+    if (!ledger_node.has_nodeid())
+        return std::nullopt;
+
+    auto const nodeID = deserializeSHAMapNodeID(ledger_node.nodeid());
+    if (!nodeID)
+        return std::nullopt;
+
+    if (treeNode->isLeaf())
+    {
+        auto const key = static_cast<SHAMapLeafNode const*>(treeNode.get())->peekItem()->key();
+        auto const expected_id = SHAMapNodeID::createID(static_cast<int>(nodeID->getDepth()), key);
+        if (nodeID->getNodeID() != expected_id.getNodeID())
+            return std::nullopt;
+    }
+
+    return nodeID;
+}
+
+}  // namespace xrpl

src/xrpld/app/ledger/detail/LedgerNodeHelpers.h

@@ -0,0 +1,75 @@
+#pragma once
+
+#include <xrpl/basics/IntrusivePointer.h>
+#include <xrpl/shamap/SHAMapNodeID.h>
+#include <xrpl/shamap/SHAMapTreeNode.h>
+
+#include <optional>
+#include <string_view>
+
+namespace protocol {
+class TMLedgerNode;
+}  // namespace protocol
+
+namespace xrpl {
+
+/**
+ * @brief Validates a ledger node proto message.
+ *
+ * This function checks whether a ledger node has the expected fields (for non-ledger base data):
+ * - The node must have `nodedata`.
+ * - If the legacy `nodeid` field is present then the new `id` and `depth` fields must not be
+ *   present.
+ * - If the new `id` or `depth` fields are present (it is a oneof field, so only one of the two can
+ *   be set) then the legacy `nodeid` must not be present.
+ * - If the `depth` field is present then it must be between 0 and SHAMap::leafDepth (inclusive).
+ *
+ * @param ledger_node The ledger node to validate.
+ * @return true if the ledger node has the expected fields, false otherwise.
+ */
+[[nodiscard]] bool
+validateLedgerNode(protocol::TMLedgerNode const& ledger_node);
+
+/**
+ * @brief Deserializes a SHAMapTreeNode from wire format data.
+ *
+ * This function attempts to create a SHAMapTreeNode from the provided data string. If the data is
+ * malformed or deserialization fails, the function returns std::nullopt instead of throwing an
+ * exception.
+ *
+ * @param data The serialized node data in wire format.
+ * @return An optional containing the deserialized tree node if successful, or std::nullopt if
+ *         deserialization fails.
+ */
+[[nodiscard]] std::optional<intr_ptr::SharedPtr<SHAMapTreeNode>>
+getTreeNode(std::string_view data);
+
+/**
+ * @brief Extracts or reconstructs the SHAMapNodeID from a ledger node proto message.
+ *
+ * This function retrieves the SHAMapNodeID for a tree node, with behavior that depends on which
+ * field is set and the node type (inner vs. leaf).
+ *
+ * When the legacy `nodeid` field is set in the message:
+ * - For all nodes: Deserializes the node ID from the field.
+ * - For leaf nodes: Validates that the node ID is consistent with the leaf's key.
+ *
+ * When the new `id` or `depth` field is set in the message:
+ * - For inner nodes: Deserializes the node ID from the `id` field. Note that root nodes are also
+ *   inner nodes.
+ * - For leaf nodes: Reconstructs the node ID using both the depth from the `depth` field and the
+ *   key from the leaf node's item.
+ *
+ * @param ledger_node The validated protocol message containing the ledger node data.
+ * @param treeNode The deserialized tree node (inner or leaf node).
+ * @return An optional containing the node ID if extraction/reconstruction succeeds, or std::nullopt
+ *         if the required fields are missing or validation fails.
+ * @note This function expects that the caller has already validated the ledger node by calling the
+ *       `validateLedgerNode` function and obtained a valid tree node by calling `getTreeNode`.
+ */
+[[nodiscard]] std::optional<SHAMapNodeID>
+getSHAMapNodeID(
+    protocol::TMLedgerNode const& ledger_node,
+    intr_ptr::SharedPtr<SHAMapTreeNode> const& treeNode);
+
+}  // namespace xrpl

src/xrpld/app/ledger/detail/TransactionAcquire.cpp

@@ -154,7 +154,7 @@ TransactionAcquire::trigger(std::shared_ptr<Peer> const& peer)
 
 SHAMapAddNode
 TransactionAcquire::takeNodes(
-    std::vector<std::pair<SHAMapNodeID, Slice>> const& data,
+    std::vector<std::pair<SHAMapNodeID, intr_ptr::SharedPtr<SHAMapTreeNode>>>&& data,
     std::shared_ptr<Peer> const& peer)
 {
     ScopedLockType sl(mtx_);
@@ -178,20 +178,19 @@ TransactionAcquire::takeNodes(
 
         ConsensusTransSetSF sf(app_, app_.getTempNodeCache());
 
-        for (auto const& d : data)
+        for (auto& d : data)
         {
             if (d.first.isRoot())
             {
                 if (mHaveRoot)
                     JLOG(journal_.debug()) << "Got root TXS node, already have it";
-                else if (!mMap->addRootNode(SHAMapHash{hash_}, d.second, nullptr).isGood())
-                {
+                else if (!mMap->addRootNode(SHAMapHash{hash_}, std::move(d.second), nullptr)
+                              .isGood())
                     JLOG(journal_.warn()) << "TX acquire got bad root node";
-                }
                 else
                     mHaveRoot = true;
             }
-            else if (!mMap->addKnownNode(d.first, d.second, &sf).isGood())
+            else if (!mMap->addKnownNode(d.first, std::move(d.second), &sf).isGood())
             {
                 JLOG(journal_.warn()) << "TX acquire got bad non-root node";
                 return SHAMapAddNode::invalid();

src/xrpld/app/ledger/detail/TransactionAcquire.h

@@ -20,8 +20,8 @@ public:
 
     SHAMapAddNode
     takeNodes(
-        std::vector<std::pair<SHAMapNodeID, Slice>> const& data,
-        std::shared_ptr<Peer> const&);
+        std::vector<std::pair<SHAMapNodeID, intr_ptr::SharedPtr<SHAMapTreeNode>>>&& data,
+        std::shared_ptr<Peer> const& peer);
 
     void
     init(int startPeers);

src/xrpld/overlay/Peer.h

@@ -17,6 +17,7 @@ enum class ProtocolFeature {
     ValidatorListPropagation,
     ValidatorList2Propagation,
     LedgerReplay,
+    LedgerNodeDepth,
 };
 
 /** Represents a peer connection in the overlay. */

src/xrpld/overlay/detail/PeerImp.cpp

@@ -30,6 +30,7 @@
 #include <mutex>
 #include <numeric>
 #include <sstream>
+#include <tuple>
 
 using namespace std::chrono_literals;
 
@@ -471,6 +472,8 @@ PeerImp::supportsFeature(ProtocolFeature f) const
             return protocol_ >= make_protocol(2, 1);
         case ProtocolFeature::ValidatorList2Propagation:
             return protocol_ >= make_protocol(2, 2);
+        case ProtocolFeature::LedgerNodeDepth:
+            return protocol_ >= make_protocol(2, 3);
         case ProtocolFeature::LedgerReplay:
             return ledgerReplayEnabled_;
     }
@@ -3237,7 +3240,8 @@ PeerImp::processLedgerRequest(std::shared_ptr<protocol::TMGetLedger> const& m)
     {
         auto const queryDepth{m->has_querydepth() ? m->querydepth() : (isHighLatency() ? 2 : 1)};
 
-        std::vector<std::pair<SHAMapNodeID, Blob>> data;
+        std::vector<std::tuple<SHAMapNodeID, Blob, bool>> data;
+        auto const useLedgerNodeDepth = supportsFeature(ProtocolFeature::LedgerNodeDepth);
 
         for (int i = 0;
              i < m->nodeids_size() && ledgerData.nodes_size() < Tuning::softMaxReplyNodes;
@@ -3259,9 +3263,22 @@ PeerImp::processLedgerRequest(std::shared_ptr<protocol::TMGetLedger> const& m)
                     {
                         if (ledgerData.nodes_size() >= Tuning::hardMaxReplyNodes)
                             break;
+
                         protocol::TMLedgerNode* node{ledgerData.add_nodes()};
-                        node->set_nodeid(d.first.getRawString());
-                        node->set_nodedata(d.second.data(), d.second.size());
+
+                        auto const& nodeData = std::get<1>(d);
+                        node->set_nodedata(nodeData.data(), nodeData.size());
+
+                        // When the LedgerNodeDepth protocol feature is not supported by the peer,
+                        // we always set the `nodeid` field. However, when it is supported then we
+                        // set the `id` field for inner nodes and the `depth` field for leaf nodes.
+                        auto const& nodeID = std::get<0>(d);
+                        if (!useLedgerNodeDepth)
+                            node->set_nodeid(nodeID.getRawString());
+                        else if (std::get<2>(d))
+                            node->set_depth(nodeID.getDepth());
+                        else
+                            node->set_id(nodeID.getRawString());
                     }
                 }
                 else

src/xrpld/overlay/detail/ProtocolVersion.cpp

@@ -21,7 +21,8 @@ namespace xrpl {
 constexpr ProtocolVersion const supportedProtocolList[]
 {
     {2, 1},
-    {2, 2}
+    {2, 2},
+    {2, 3},
 };
 // clang-format on