[ALPHANET] Repo

include/xrpl/ledger/helpers/RepoHelpers.h

@@ -0,0 +1,85 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/Asset.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+#include <cstdint>
+
+namespace xrpl {
+namespace repo {
+
+/**
+ * Seconds in a year, the denominator of the annualized interest rate.
+ */
+
+/**
+ * A repo is active once the buyer has accepted it, which is recorded by
+ * sfStartDate. Before that it is a pending offer.
+ */
+[[nodiscard]] inline bool
+isActive(SLE::const_ref sleRepo)
+{
+    return sleRepo->isFieldPresent(sfStartDate);
+}
+
+/**
+ * The amount the seller owes to repurchase the collateral.
+ *
+ * PurchasePrice * (1 + InterestRate * elapsed / kSecondsInYear), where elapsed
+ * runs from StartDate to the close time, capped at MaturityDate so the seller
+ * never pays for time past maturity. Computed in Number and rounded up, so
+ * rounding never favours the seller.
+ */
+[[nodiscard]] STAmount
+repurchaseAmount(SLE::const_ref sleRepo, std::uint32_t closeTime);
+
+/**
+ * Lock the collateral out of the seller's spendable balance.
+ *
+ * XRP is deducted from the account balance by the caller; this handles the
+ * issued-asset cases the same way an escrow does.
+ */
+[[nodiscard]] TER
+lockCollateral(
+    ApplyView& view,
+    AccountID const& issuer,
+    AccountID const& seller,
+    STAmount const& amount,
+    beast::Journal journal);
+
+/**
+ * The XLS-85 checks that decide whether collateral may be locked at all.
+ *
+ * Both parties are checked, not just the seller: the buyer receives the
+ * collateral if the repo defaults, so an unauthorized or frozen buyer would
+ * leave the collateral unable to move at exactly the moment it must.
+ */
+[[nodiscard]] TER
+checkCollateral(
+    ReadView const& view,
+    AccountID const& seller,
+    AccountID const& buyer,
+    STAmount const& collateral,
+    beast::Journal journal);
+
+/**
+ * Return the locked collateral to an account and remove the entry.
+ *
+ * Used by cancel, close and default; they differ only in who receives the
+ * collateral and whether any cash moved first.
+ */
+[[nodiscard]] TER
+releaseAndDelete(
+    ApplyViewContext ctx,
+    SLE::ref sleRepo,
+    AccountID const& receiver,
+    beast::Journal journal);
+
+}  // namespace repo
+}  // namespace xrpl

include/xrpl/protocol/Indexes.h

@@ -366,6 +366,18 @@ vault(uint256 const& vaultKey)
 Keylet
 loanBroker(AccountID const& owner, SeqProxy const& seq) noexcept;
 
+/**
+ * A repurchase agreement, keyed by the seller and the creating sequence.
+ */
+Keylet
+repo(AccountID const& seller, SeqProxy const& seq) noexcept;
+
+inline Keylet
+repo(uint256 const& repoID)
+{
+    return {ltREPO, repoID};
+}
+
 inline Keylet
 loanBroker(uint256 const& key)
 {

include/xrpl/protocol/TER.h

@@ -377,6 +377,8 @@ enum TECcodes : TERUnderlyingType {
     tecNO_SPONSOR_PERMISSION = 200,
     tecOUT_OF_GAS = 201,
     tecBYTECODE_REJECTED = 202,
+    tecREPO_ACTIVE = 211,
+    tecREPO_PENDING = 212,
 };
 
 //------------------------------------------------------------------------------

include/xrpl/protocol/detail/features.macro

@@ -15,6 +15,7 @@
 // Add new amendments to the top of this list.
 // Keep it sorted in reverse chronological order.
 
+XRPL_FEATURE(Repo,                        Supported::No,  VoteBehavior::DefaultNo)
 XRPL_FEATURE(SmartEscrow,                 Supported::No,  VoteBehavior::DefaultNo)
 XRPL_FEATURE(LendingProtocolV1_2,         Supported::No,  VoteBehavior::DefaultNo)
 XRPL_FIX    (Cleanup3_5_0,                Supported::Yes, VoteBehavior::DefaultNo)

include/xrpl/protocol/detail/ledger_entries.macro

@@ -522,6 +522,30 @@ LEDGER_ENTRY(ltVAULT, 0x0084, Vault, vault, ({
     // no PermissionedDomainID ever (use MPTIssuance.sfDomainID)
 }))
 
+/**
+ * A bilateral repurchase agreement. The seller locks collateral and receives
+ * cash; the entry is pending until the buyer accepts, active thereafter.
+ * \sa keylet::repo
+ */
+LEDGER_ENTRY(ltREPO, 0x0095, Repo, repo, ({
+    {sfAccount,              SoeRequired},
+    {sfCounterparty,         SoeRequired},
+    {sfCollateralAmount,     SoeRequired, SoeMptSupported},
+    {sfPurchasePrice,        SoeRequired, SoeMptSupported},
+    {sfInterestRate,         SoeRequired},
+    {sfExpiration,           SoeRequired},
+    {sfStartDate,            SoeOptional},
+    {sfMaturityDate,         SoeRequired},
+    {sfGracePeriod,          SoeRequired},
+    {sfTransferRate,         SoeOptional},
+    {sfData,                 SoeOptional},
+    {sfOwnerNode,            SoeRequired},
+    {sfDestinationNode,      SoeRequired},
+    {sfIssuerNode,           SoeOptional},
+    {sfPreviousTxnID,        SoeRequired},
+    {sfPreviousTxnLgrSeq,    SoeRequired},
+}))
+
 /** Reserve 0x0084-0x0087 for future Vault-related objects. */
 
 /** A ledger object representing a loan broker

include/xrpl/protocol/detail/sfields.macro

@@ -115,6 +115,7 @@ TYPED_SFIELD(sfConfidentialBalanceVersion, UINT32,  69)
 TYPED_SFIELD(sfSponsoredOwnerCount,      UINT32,    70)
 TYPED_SFIELD(sfSponsoringOwnerCount,     UINT32,    71)
 TYPED_SFIELD(sfSponsoringAccountCount,   UINT32,    72)
+TYPED_SFIELD(sfMaturityDate,             UINT32,    95)
 TYPED_SFIELD(sfRemainingOwnerCount,      UINT32,    73)
 TYPED_SFIELD(sfSponsorFlags,             UINT32,    74)
 TYPED_SFIELD(sfSubscriptionDate,         UINT32,    75)
@@ -220,6 +221,7 @@ TYPED_SFIELD(sfLoanID,                   UINT256,   38)
 TYPED_SFIELD(sfReferenceHolding,         UINT256,   39)
 TYPED_SFIELD(sfBlindingFactor,           UINT256,   40)
 TYPED_SFIELD(sfObjectID,                 UINT256,   41)
+TYPED_SFIELD(sfRepoID,                   UINT256,   47)
 
 // number (common)
 TYPED_SFIELD(sfNumber,                   NUMBER,     1)
@@ -282,6 +284,8 @@ TYPED_SFIELD(sfLPTokenBalance,           AMOUNT,    31)
 TYPED_SFIELD(sfFeeAmount,                AMOUNT,    32)
 TYPED_SFIELD(sfMaxFee,                   AMOUNT,    33)
 TYPED_SFIELD(sfFeeAmountDelta,           AMOUNT,    34)
+TYPED_SFIELD(sfCollateralAmount,         AMOUNT,    39)
+TYPED_SFIELD(sfPurchasePrice,            AMOUNT,    40)
 
 // variable length (common)
 TYPED_SFIELD(sfPublicKey,                VL,         1)

include/xrpl/protocol/detail/transactions.macro

@@ -1181,3 +1181,60 @@ TRANSACTION(ttUNL_MODIFY, 102, UNLModify,
     {sfLedgerSequence, SoeRequired},
     {sfUNLModifyValidator, SoeRequired},
 }))
+
+/** This transaction type offers a repurchase agreement and locks its collateral. */
+#if TRANSACTION_INCLUDE
+#   include <xrpl/tx/transactors/repo/RepoCreate.h>
+#endif
+TRANSACTION(ttREPO_CREATE, 114, RepoCreate,
+    ({.delegable = Delegation::Delegable, .amendment = featureRepo}),
+    ({
+    {sfCounterparty,         SoeRequired},
+    {sfCollateralAmount,     SoeRequired, SoeMptSupported},
+    {sfPurchasePrice,        SoeRequired, SoeMptSupported},
+    {sfInterestRate,         SoeRequired},
+    {sfExpiration,           SoeRequired},
+    {sfMaturityDate,         SoeRequired},
+    {sfGracePeriod,          SoeRequired},
+    {sfData,                 SoeOptional},
+}))
+
+/** This transaction type accepts a pending repo, delivering the cash. */
+#if TRANSACTION_INCLUDE
+#   include <xrpl/tx/transactors/repo/RepoAccept.h>
+#endif
+TRANSACTION(ttREPO_ACCEPT, 115, RepoAccept,
+    ({.delegable = Delegation::Delegable, .amendment = featureRepo}),
+    ({
+    {sfRepoID,               SoeRequired},
+}))
+
+/** This transaction type cancels a pending repo and returns the collateral. */
+#if TRANSACTION_INCLUDE
+#   include <xrpl/tx/transactors/repo/RepoCancel.h>
+#endif
+TRANSACTION(ttREPO_CANCEL, 116, RepoCancel,
+    ({.delegable = Delegation::Delegable, .amendment = featureRepo}),
+    ({
+    {sfRepoID,               SoeRequired},
+}))
+
+/** This transaction type repurchases the collateral, paying principal plus interest. */
+#if TRANSACTION_INCLUDE
+#   include <xrpl/tx/transactors/repo/RepoClose.h>
+#endif
+TRANSACTION(ttREPO_CLOSE, 117, RepoClose,
+    ({.delegable = Delegation::Delegable, .amendment = featureRepo}),
+    ({
+    {sfRepoID,               SoeRequired},
+}))
+
+/** This transaction type closes out a defaulted repo, delivering the collateral. */
+#if TRANSACTION_INCLUDE
+#   include <xrpl/tx/transactors/repo/RepoDefault.h>
+#endif
+TRANSACTION(ttREPO_DEFAULT, 118, RepoDefault,
+    ({.delegable = Delegation::Delegable, .amendment = featureRepo}),
+    ({
+    {sfRepoID,               SoeRequired},
+}))