Add deep freeze feature (XLS-77d) (#5187)

- spec: XRPLF/XRPL-Standards#220 - amendment: "DeepFreeze" - implemented deep freeze spec to allow token issuers to prevent currency holders from being able to acquire more of these tokens. - in combination with normal freeze, deep freeze effectively prevents any balance trust line balance change of a currency holder (except direct issuer <-> holder payments). - added 2 new invariant checks to verify that deep freeze cannot be enacted without normal freeze and transfer is not frozen. - made some fixes to existing freeze handling. Co-authored-by: Ed Hennis <[email protected]> Co-authored-by: Howard Hinnant <[email protected]>
XRPLF · Jan 31, 2025 · 33e1c42 · 33e1c42
1 parent 1b75dc8
commit 33e1c42
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Showing 21 changed files with 2,479 additions and 49 deletions.
diff --git a/include/xrpl/protocol/Feature.h b/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 = 85;
+static constexpr std::size_t numFeatures = 86;
 
 /** Amendments that this server supports and the default voting behavior.
    Whether they are enabled depends on the Rules defined in the validated

diff --git a/include/xrpl/protocol/LedgerFormats.h b/include/xrpl/protocol/LedgerFormats.h
@@ -160,10 +160,12 @@ enum LedgerSpecificFlags {
     lsfHighAuth = 0x00080000,
     lsfLowNoRipple = 0x00100000,
     lsfHighNoRipple = 0x00200000,
-    lsfLowFreeze = 0x00400000,   // True, low side has set freeze flag
-    lsfHighFreeze = 0x00800000,  // True, high side has set freeze flag
-    lsfAMMNode = 0x01000000,     // True, trust line to AMM. Used by client
-                                 // apps to identify payments via AMM.
+    lsfLowFreeze = 0x00400000,      // True, low side has set freeze flag
+    lsfHighFreeze = 0x00800000,     // True, high side has set freeze flag
+    lsfLowDeepFreeze = 0x02000000,  // True, low side has set deep freeze flag
+    lsfHighDeepFreeze = 0x04000000, // True, high side has set deep freeze flag
+    lsfAMMNode = 0x01000000,        // True, trust line to AMM. Used by client
+                                    // apps to identify payments via AMM.
 
     // ltSIGNER_LIST
     lsfOneOwnerCount = 0x00010000,  // True, uses only one OwnerCount

diff --git a/include/xrpl/protocol/TxFlags.h b/include/xrpl/protocol/TxFlags.h
@@ -114,9 +114,11 @@ constexpr std::uint32_t tfSetNoRipple                      = 0x00020000;
 constexpr std::uint32_t tfClearNoRipple                    = 0x00040000;
 constexpr std::uint32_t tfSetFreeze                        = 0x00100000;
 constexpr std::uint32_t tfClearFreeze                      = 0x00200000;
+constexpr std::uint32_t tfSetDeepFreeze                    = 0x00400000;
+constexpr std::uint32_t tfClearDeepFreeze                  = 0x00800000;
 constexpr std::uint32_t tfTrustSetMask =
     ~(tfUniversal | tfSetfAuth | tfSetNoRipple | tfClearNoRipple | tfSetFreeze |
-      tfClearFreeze);
+      tfClearFreeze | tfSetDeepFreeze | tfClearDeepFreeze);
 
 // EnableAmendment flags:
 constexpr std::uint32_t tfGotMajority                      = 0x00010000;

diff --git a/include/xrpl/protocol/detail/features.macro b/include/xrpl/protocol/detail/features.macro
@@ -29,6 +29,7 @@
 // If you add an amendment here, then do not forget to increment `numFeatures`
 // in include/xrpl/protocol/Feature.h.
 
+XRPL_FEATURE(DeepFreeze,                 Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FEATURE(PermissionedDomains,        Supported::no,  VoteBehavior::DefaultNo)
 XRPL_FEATURE(DynamicNFT,                 Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FEATURE(Credentials,                Supported::yes, VoteBehavior::DefaultNo)
@@ -116,3 +117,4 @@ XRPL_FIX    (NFTokenNegOffer,       Supported::yes, VoteBehavior::Obsolete)
 XRPL_FIX    (NFTokenDirV1,          Supported::yes, VoteBehavior::Obsolete)
 XRPL_FEATURE(NonFungibleTokensV1,   Supported::yes, VoteBehavior::Obsolete)
 XRPL_FEATURE(CryptoConditionsSuite, Supported::yes, VoteBehavior::Obsolete)
+
diff --git a/include/xrpl/protocol/jss.h b/include/xrpl/protocol/jss.h
@@ -284,6 +284,8 @@ JSS(flags);                   // out: AccountOffers,
 JSS(forward);                 // in: AccountTx
 JSS(freeze);                  // out: AccountLines
 JSS(freeze_peer);             // out: AccountLines
+JSS(deep_freeze);                  // out: AccountLines
+JSS(deep_freeze_peer);             // out: AccountLines
 JSS(frozen_balances);         // out: GatewayBalances
 JSS(full);                    // in: LedgerClearer, handlers/Ledger
 JSS(full_reply);              // out: PathFind