VaultDeposit.cpp

#include <xrpld/app/tx/detail/MPTokenAuthorize.h>
#include <xrpld/app/tx/detail/VaultDeposit.h>
 
#include <xrpl/ledger/CredentialHelpers.h>
#include <xrpl/ledger/View.h>
#include <xrpl/protocol/Feature.h>
#include <xrpl/protocol/Indexes.h>
#include <xrpl/protocol/LedgerFormats.h>
#include <xrpl/protocol/MPTIssue.h>
#include <xrpl/protocol/SField.h>
#include <xrpl/protocol/STNumber.h>
#include <xrpl/protocol/TER.h>
#include <xrpl/protocol/TxFlags.h>
 
namespace xrpl {
 
NotTEC
VaultDeposit::preflight(PreflightContext const& ctx)
{
    if (ctx.tx[sfVaultID] == beast::zero)
    {
        JLOG(ctx.j.debug()) << "VaultDeposit: zero/empty vault ID.";
        return temMALFORMED;
    }
 
    if (ctx.tx[sfAmount] <= beast::zero)
        return temBAD_AMOUNT;
 
    return tesSUCCESS;
}
 
TER
VaultDeposit::preclaim(PreclaimContext const& ctx)
{
    auto const vault = ctx.view.read(keylet::vault(ctx.tx[sfVaultID]));
    if (!vault)
        return tecNO_ENTRY;
 
    auto const& account = ctx.tx[sfAccount];
    auto const assets = ctx.tx[sfAmount];
    auto const vaultAsset = vault->at(sfAsset);
    if (assets.asset() != vaultAsset)
        return tecWRONG_ASSET;
 
    auto const& vaultAccount = vault->at(sfAccount);
    if (auto ter = canTransfer(ctx.view, vaultAsset, account, vaultAccount);
        !isTesSuccess(ter))
    {
        JLOG(ctx.j.debug())
            << "VaultDeposit: vault assets are non-transferable.";
        return ter;
    }
 
    auto const mptIssuanceID = vault->at(sfShareMPTID);
    auto const vaultShare = MPTIssue(mptIssuanceID);
    if (vaultShare == assets.asset())
    {
        // LCOV_EXCL_START
        JLOG(ctx.j.error())
            << "VaultDeposit: vault shares and assets cannot be same.";
        return tefINTERNAL;
        // LCOV_EXCL_STOP
    }
 
    auto const sleIssuance = ctx.view.read(keylet::mptIssuance(mptIssuanceID));
    if (!sleIssuance)
    {
        // LCOV_EXCL_START
        JLOG(ctx.j.error())
            << "VaultDeposit: missing issuance of vault shares.";
        return tefINTERNAL;
        // LCOV_EXCL_STOP
    }
 
    if (sleIssuance->isFlag(lsfMPTLocked))
    {
        // LCOV_EXCL_START
        JLOG(ctx.j.error())
            << "VaultDeposit: issuance of vault shares is locked.";
        return tefINTERNAL;
        // LCOV_EXCL_STOP
    }
 
    // Cannot deposit inside Vault an Asset frozen for the depositor
    if (isFrozen(ctx.view, account, vaultAsset))
        return vaultAsset.holds<Issue>() ? tecFROZEN : tecLOCKED;
 
    // Cannot deposit if the shares of the vault are frozen
    if (isFrozen(ctx.view, account, vaultShare))
        return tecLOCKED;
 
    if (vault->isFlag(lsfVaultPrivate) && account != vault->at(sfOwner))
    {
        auto const maybeDomainID = sleIssuance->at(~sfDomainID);
        // Since this is a private vault and the account is not its owner, we
        // perform authorization check based on DomainID read from sleIssuance.
        // Had the vault shares been a regular MPToken, we would allow
        // authorization granted by the Issuer explicitly, but Vault uses Issuer
        // pseudo-account, which cannot grant an authorization.
        if (maybeDomainID)
        {
            // As per validDomain documentation, we suppress tecEXPIRED error
            // here, so we can delete any expired credentials inside doApply.
            if (auto const err =
                    credentials::validDomain(ctx.view, *maybeDomainID, account);
                !isTesSuccess(err) && err != tecEXPIRED)
                return err;
        }
        else
            return tecNO_AUTH;
    }
 
    // Source MPToken must exist (if asset is an MPT)
    if (auto const ter = requireAuth(ctx.view, vaultAsset, account);
        !isTesSuccess(ter))
        return ter;
 
    // Asset issuer does not have any balance, they can just create funds by
    // depositing in the vault.
    if ((vaultAsset.native() || vaultAsset.getIssuer() != account) &&
        accountHolds(
            ctx.view,
            account,
            vaultAsset,
            FreezeHandling::fhZERO_IF_FROZEN,
            AuthHandling::ahZERO_IF_UNAUTHORIZED,
            ctx.j) < assets)
        return tecINSUFFICIENT_FUNDS;
 
    return tesSUCCESS;
}
 
TER
VaultDeposit::doApply()
{
    auto const vault = view().peek(keylet::vault(ctx_.tx[sfVaultID]));
    if (!vault)
        return tefINTERNAL;  // LCOV_EXCL_LINE
 
    auto const amount = ctx_.tx[sfAmount];
    // Make sure the depositor can hold shares.
    auto const mptIssuanceID = (*vault)[sfShareMPTID];
    auto const sleIssuance = view().read(keylet::mptIssuance(mptIssuanceID));
    if (!sleIssuance)
    {
        // LCOV_EXCL_START
        JLOG(j_.error()) << "VaultDeposit: missing issuance of vault shares.";
        return tefINTERNAL;
        // LCOV_EXCL_STOP
    }
 
    auto const& vaultAccount = vault->at(sfAccount);
    // Note, vault owner is always authorized
    if (vault->isFlag(lsfVaultPrivate) && account_ != vault->at(sfOwner))
    {
        if (auto const err = enforceMPTokenAuthorization(
                ctx_.view(), mptIssuanceID, account_, mPriorBalance, j_);
            !isTesSuccess(err))
            return err;
    }
    else  // !vault->isFlag(lsfVaultPrivate) || account_ == vault->at(sfOwner)
    {
        // No authorization needed, but must ensure there is MPToken
        if (!view().exists(keylet::mptoken(mptIssuanceID, account_)))
        {
            if (auto const err = authorizeMPToken(
                    view(),
                    mPriorBalance,
                    mptIssuanceID->value(),
                    account_,
                    ctx_.journal);
                !isTesSuccess(err))
                return err;
        }
 
        // If the vault is private, set the authorized flag for the vault owner
        if (vault->isFlag(lsfVaultPrivate))
        {
            // This follows from the reverse of the outer enclosing if condition
            XRPL_ASSERT(
                account_ == vault->at(sfOwner),
                "xrpl::VaultDeposit::doApply : account is owner");
            if (auto const err = authorizeMPToken(
                    view(),
                    mPriorBalance,              // priorBalance
                    mptIssuanceID->value(),     // mptIssuanceID
                    sleIssuance->at(sfIssuer),  // account
                    ctx_.journal,
                    {},       // flags
                    account_  // holderID
                );
                !isTesSuccess(err))
                return err;
        }
    }
 
    STAmount sharesCreated = {vault->at(sfShareMPTID)}, assetsDeposited;
    try
    {
        // Compute exchange before transferring any amounts.
        {
            auto const maybeShares =
                assetsToSharesDeposit(vault, sleIssuance, amount);
            if (!maybeShares)
                return tecINTERNAL;  // LCOV_EXCL_LINE
            sharesCreated = *maybeShares;
        }
        if (sharesCreated == beast::zero)
            return tecPRECISION_LOSS;
 
        auto const maybeAssets =
            sharesToAssetsDeposit(vault, sleIssuance, sharesCreated);
        if (!maybeAssets)
            return tecINTERNAL;  // LCOV_EXCL_LINE
        else if (*maybeAssets > amount)
        {
            // LCOV_EXCL_START
            JLOG(j_.error()) << "VaultDeposit: would take more than offered.";
            return tecINTERNAL;
            // LCOV_EXCL_STOP
        }
        assetsDeposited = *maybeAssets;
    }
    catch (std::overflow_error const&)
    {
        // It's easy to hit this exception from Number with large enough Scale
        // so we avoid spamming the log and only use debug here.
        JLOG(j_.debug())  //
            << "VaultDeposit: overflow error with"
            << " scale=" << (int)vault->at(sfScale).value()  //
            << ", assetsTotal=" << vault->at(sfAssetsTotal).value()
            << ", sharesTotal=" << sleIssuance->at(sfOutstandingAmount)
            << ", amount=" << amount;
        return tecPATH_DRY;
    }
 
    XRPL_ASSERT(
        sharesCreated.asset() != assetsDeposited.asset(),
        "xrpl::VaultDeposit::doApply : assets are not shares");
 
    vault->at(sfAssetsTotal) += assetsDeposited;
    vault->at(sfAssetsAvailable) += assetsDeposited;
    view().update(vault);
 
    // A deposit must not push the vault over its limit.
    auto const maximum = *vault->at(sfAssetsMaximum);
    if (maximum != 0 && *vault->at(sfAssetsTotal) > maximum)
        return tecLIMIT_EXCEEDED;
 
    // Transfer assets from depositor to vault.
    if (auto const ter = accountSend(
            view(),
            account_,
            vaultAccount,
            assetsDeposited,
            j_,
            WaiveTransferFee::Yes);
        !isTesSuccess(ter))
        return ter;
 
    // Sanity check
    if (accountHolds(
            view(),
            account_,
            assetsDeposited.asset(),
            FreezeHandling::fhIGNORE_FREEZE,
            AuthHandling::ahIGNORE_AUTH,
            j_) < beast::zero)
    {
        // LCOV_EXCL_START
        JLOG(j_.error()) << "VaultDeposit: negative balance of account assets.";
        return tefINTERNAL;
        // LCOV_EXCL_STOP
    }
 
    // Transfer shares from vault to depositor.
    if (auto const ter = accountSend(
            view(),
            vaultAccount,
            account_,
            sharesCreated,
            j_,
            WaiveTransferFee::Yes);
        !isTesSuccess(ter))
        return ter;
 
    return tesSUCCESS;
}
 
}  // namespace xrpl