Add AMMClawback Transaction (XLS-0073d)

include/xrpl/protocol/Feature.h

@@ -80,7 +80,7 @@ namespace detail {
 // Feature.cpp. Because it's only used to reserve storage, and determine how
 // large to make the FeatureBitset, it MAY be larger. It MUST NOT be less than
 // the actual number of amendments. A LogicError on startup will verify this.
-static constexpr std::size_t numFeatures = 79;
+static constexpr std::size_t numFeatures = 80;
 
 /** Amendments that this server supports and the default voting behavior.
    Whether they are enabled depends on the Rules defined in the validated
@@ -372,6 +372,7 @@ extern uint256 const fixEnforceNFTokenTrustline;
 extern uint256 const fixInnerObjTemplate2;
 extern uint256 const featureInvariantsV1_1;
 extern uint256 const fixNFTokenPageLinks;
+extern uint256 const featureAMMClawback;
 
 }  // namespace ripple
 

include/xrpl/protocol/SField.h

@@ -587,6 +587,7 @@ extern SF_ACCOUNT const sfUnauthorize;
 extern SF_ACCOUNT const sfRegularKey;
 extern SF_ACCOUNT const sfNFTokenMinter;
 extern SF_ACCOUNT const sfEmitCallback;
+extern SF_ACCOUNT const sfHolder;
 
 // account (uncommon)
 extern SF_ACCOUNT const sfHookAccount;

include/xrpl/protocol/TxFlags.h

@@ -181,6 +181,10 @@ constexpr std::uint32_t tfDepositSubTx =
 constexpr std::uint32_t tfWithdrawMask = ~(tfUniversal | tfWithdrawSubTx);
 constexpr std::uint32_t tfDepositMask = ~(tfUniversal | tfDepositSubTx);
 
+// AMMClawback flags:
+constexpr std::uint32_t tfClawTwoAssets                = 0x00000001;
+constexpr std::uint32_t tfAMMClawbackMask = ~(tfUniversal | tfClawTwoAssets);
+
 // BridgeModify flags:
 constexpr std::uint32_t tfClearAccountCreateAmount     = 0x00010000;
 constexpr std::uint32_t tfBridgeModifyMask = ~(tfUniversal | tfClearAccountCreateAmount);

include/xrpl/protocol/TxFormats.h

@@ -142,6 +142,9 @@ enum TxType : std::uint16_t
     /** This transaction claws back issued tokens. */
     ttCLAWBACK = 30,
 
+    /** This transaction claws back tokens from an AMM pool. */
+    ttAMM_CLAWBACK = 31,
+
     /** This transaction type creates an AMM instance */
     ttAMM_CREATE = 35,
 

include/xrpl/protocol/jss.h

@@ -49,6 +49,7 @@ JSS(AccountRoot);          // ledger type.
 JSS(AccountSet);           // transaction type.
 JSS(AMM);                  // ledger type
 JSS(AMMBid);               // transaction type
+JSS(AMMClawback);          // transaction type.
 JSS(AMMID);                // field
 JSS(AMMCreate);            // transaction type
 JSS(AMMDeposit);           // transaction type
@@ -89,6 +90,7 @@ JSS(EscrowFinish);         // transaction type.
 JSS(Fee);                  // in/out: TransactionSign; field.
 JSS(FeeSettings);          // ledger type.
 JSS(Flags);                // in/out: TransactionSign; field.
+JSS(Holder);               // field.
 JSS(Invalid);              //
 JSS(LastLedgerSequence);   // in: TransactionSign; field
 JSS(LastUpdateTime);       // field.

src/libxrpl/protocol/Feature.cpp

@@ -501,6 +501,7 @@ REGISTER_FIX    (fixNFTokenPageLinks,           Supported::yes, VoteBehavior::De
 // InvariantsV1_1 will be changes to Supported::yes when all the
 // invariants expected to be included under it are complete.
 REGISTER_FEATURE(InvariantsV1_1,                Supported::no, VoteBehavior::DefaultNo);
+REGISTER_FEATURE(AMMClawback,                   Supported::yes, VoteBehavior::DefaultNo);
 
 // The following amendments are obsolete, but must remain supported
 // because they could potentially get enabled.

src/libxrpl/protocol/SField.cpp

@@ -319,6 +319,7 @@ CONSTRUCT_TYPED_SFIELD(sfUnauthorize,           "Unauthorize",          ACCOUNT,
 CONSTRUCT_TYPED_SFIELD(sfRegularKey,            "RegularKey",           ACCOUNT,    8);
 CONSTRUCT_TYPED_SFIELD(sfNFTokenMinter,         "NFTokenMinter",        ACCOUNT,    9);
 CONSTRUCT_TYPED_SFIELD(sfEmitCallback,          "EmitCallback",         ACCOUNT,   10);
+CONSTRUCT_TYPED_SFIELD(sfHolder,                "Holder",               ACCOUNT,   11);
 
 // account (uncommon)
 CONSTRUCT_TYPED_SFIELD(sfHookAccount,           "HookAccount",          ACCOUNT,   16);

src/libxrpl/protocol/TER.cpp

@@ -159,7 +159,7 @@ transResults()
 
         MAKE_ERROR(temMALFORMED,                 "Malformed transaction."),
         MAKE_ERROR(temBAD_AMM_TOKENS,            "Malformed: Invalid LPTokens."),
-        MAKE_ERROR(temBAD_AMOUNT,                "Can only send positive amounts."),
+        MAKE_ERROR(temBAD_AMOUNT,                "Malformed: Bad amount."),
         MAKE_ERROR(temBAD_CURRENCY,              "Malformed: Bad currency."),
         MAKE_ERROR(temBAD_EXPIRATION,            "Malformed: Bad expiration."),
         MAKE_ERROR(temBAD_FEE,                   "Invalid fee, negative or not XRP."),

src/libxrpl/protocol/TxFormats.cpp

@@ -381,6 +381,16 @@ TxFormats::TxFormats()
         },
         commonFields);
 
+    add(jss::AMMClawback,
+        ttAMM_CLAWBACK,
+        {
+            {sfHolder, soeREQUIRED},
+            {sfAsset, soeREQUIRED},
+            {sfAsset2, soeREQUIRED},
+            {sfAmount, soeOPTIONAL},
+        },
+        commonFields);
+
     add(jss::XChainCreateBridge,
         ttXCHAIN_CREATE_BRIDGE,
         {