MPTInvariant.cpp

#include <xrpl/tx/invariants/MPTInvariant.h>
//
#include <xrpl/basics/Log.h>
#include <xrpl/beast/utility/instrumentation.h>
#include <xrpl/protocol/Feature.h>
#include <xrpl/protocol/Indexes.h>
#include <xrpl/protocol/MPTIssue.h>
#include <xrpl/protocol/TxFormats.h>
#include <xrpl/tx/invariants/InvariantCheckPrivilege.h>
 
namespace xrpl {
 
void
ValidMPTIssuance::visitEntry(
    bool isDelete,
    std::shared_ptr<SLE const> const& before,
    std::shared_ptr<SLE const> const& after)
{
    if (after && after->getType() == ltMPTOKEN_ISSUANCE)
    {
        if (isDelete)
        {
            mptIssuancesDeleted_++;
        }
        else if (!before)
        {
            mptIssuancesCreated_++;
        }
    }
 
    if (after && after->getType() == ltMPTOKEN)
    {
        if (isDelete)
        {
            mptokensDeleted_++;
        }
        else if (!before)
        {
            mptokensCreated_++;
            MPTIssue const mptIssue{after->at(sfMPTokenIssuanceID)};
            if (mptIssue.getIssuer() == after->at(sfAccount))
                mptCreatedByIssuer_ = true;
        }
    }
}
 
bool
ValidMPTIssuance::finalize(
    STTx const& tx,
    TER const result,
    XRPAmount const _fee,
    ReadView const& view,
    beast::Journal const& j) const
{
    if (isTesSuccess(result))
    {
        auto const& rules = view.rules();
        [[maybe_unused]]
        bool const enforceCreatedByIssuer =
            rules.enabled(featureSingleAssetVault) || rules.enabled(featureLendingProtocol);
        if (mptCreatedByIssuer_)
        {
            JLOG(j.fatal()) << "Invariant failed: MPToken created for the MPT issuer";
            // The comment above starting with "assert(enforce)" explains this
            // assert.
            XRPL_ASSERT_PARTS(
                enforceCreatedByIssuer, "xrpl::ValidMPTIssuance::finalize", "no issuer MPToken");
            if (enforceCreatedByIssuer)
                return false;
        }
 
        auto const txnType = tx.getTxnType();
        if (hasPrivilege(tx, createMPTIssuance))
        {
            if (mptIssuancesCreated_ == 0)
            {
                JLOG(j.fatal()) << "Invariant failed: transaction "
                                   "succeeded without creating a MPT issuance";
            }
            else if (mptIssuancesDeleted_ != 0)
            {
                JLOG(j.fatal()) << "Invariant failed: transaction "
                                   "succeeded while removing MPT issuances";
            }
            else if (mptIssuancesCreated_ > 1)
            {
                JLOG(j.fatal()) << "Invariant failed: transaction "
                                   "succeeded but created multiple issuances";
            }
 
            return mptIssuancesCreated_ == 1 && mptIssuancesDeleted_ == 0;
        }
 
        if (hasPrivilege(tx, destroyMPTIssuance))
        {
            if (mptIssuancesDeleted_ == 0)
            {
                JLOG(j.fatal()) << "Invariant failed: MPT issuance deletion "
                                   "succeeded without removing a MPT issuance";
            }
            else if (mptIssuancesCreated_ > 0)
            {
                JLOG(j.fatal()) << "Invariant failed: MPT issuance deletion "
                                   "succeeded while creating MPT issuances";
            }
            else if (mptIssuancesDeleted_ > 1)
            {
                JLOG(j.fatal()) << "Invariant failed: MPT issuance deletion "
                                   "succeeded but deleted multiple issuances";
            }
 
            return mptIssuancesCreated_ == 0 && mptIssuancesDeleted_ == 1;
        }
 
        bool const lendingProtocolEnabled = view.rules().enabled(featureLendingProtocol);
        // ttESCROW_FINISH may authorize an MPT, but it can't have the
        // mayAuthorizeMPT privilege, because that may cause
        // non-amendment-gated side effects.
        bool const enforceEscrowFinish = (txnType == ttESCROW_FINISH) &&
            (view.rules().enabled(featureSingleAssetVault) || lendingProtocolEnabled);
        if (hasPrivilege(tx, mustAuthorizeMPT | mayAuthorizeMPT) || enforceEscrowFinish)
        {
            bool const submittedByIssuer = tx.isFieldPresent(sfHolder);
 
            if (mptIssuancesCreated_ > 0)
            {
                JLOG(j.fatal()) << "Invariant failed: MPT authorize "
                                   "succeeded but created MPT issuances";
                return false;
            }
            if (mptIssuancesDeleted_ > 0)
            {
                JLOG(j.fatal()) << "Invariant failed: MPT authorize "
                                   "succeeded but deleted issuances";
                return false;
            }
            if (lendingProtocolEnabled && mptokensCreated_ + mptokensDeleted_ > 1)
            {
                JLOG(j.fatal()) << "Invariant failed: MPT authorize succeeded "
                                   "but created/deleted bad number mptokens";
                return false;
            }
            if (submittedByIssuer && (mptokensCreated_ > 0 || mptokensDeleted_ > 0))
            {
                JLOG(j.fatal()) << "Invariant failed: MPT authorize submitted by issuer "
                                   "succeeded but created/deleted mptokens";
                return false;
            }
            if (!submittedByIssuer && hasPrivilege(tx, mustAuthorizeMPT) &&
                (mptokensCreated_ + mptokensDeleted_ != 1))
            {
                // if the holder submitted this tx, then a mptoken must be
                // either created or deleted.
                JLOG(j.fatal()) << "Invariant failed: MPT authorize submitted by holder "
                                   "succeeded but created/deleted bad number of mptokens";
                return false;
            }
 
            return true;
        }
        if (txnType == ttESCROW_FINISH)
        {
            // ttESCROW_FINISH may authorize an MPT, but it can't have the
            // mayAuthorizeMPT privilege, because that may cause
            // non-amendment-gated side effects.
            XRPL_ASSERT_PARTS(
                !enforceEscrowFinish, "xrpl::ValidMPTIssuance::finalize", "not escrow finish tx");
            return true;
        }
 
        if (hasPrivilege(tx, mayDeleteMPT) && mptokensDeleted_ == 1 && mptokensCreated_ == 0 &&
            mptIssuancesCreated_ == 0 && mptIssuancesDeleted_ == 0)
            return true;
    }
 
    if (mptIssuancesCreated_ != 0)
    {
        JLOG(j.fatal()) << "Invariant failed: a MPT issuance was created";
    }
    else if (mptIssuancesDeleted_ != 0)
    {
        JLOG(j.fatal()) << "Invariant failed: a MPT issuance was deleted";
    }
    else if (mptokensCreated_ != 0)
    {
        JLOG(j.fatal()) << "Invariant failed: a MPToken was created";
    }
    else if (mptokensDeleted_ != 0)
    {
        JLOG(j.fatal()) << "Invariant failed: a MPToken was deleted";
    }
 
    return mptIssuancesCreated_ == 0 && mptIssuancesDeleted_ == 0 && mptokensCreated_ == 0 &&
        mptokensDeleted_ == 0;
}
 
}  // namespace xrpl