Skip to content

Commit

Permalink
Add lsf[High/Low]AMMNode to indicate which side of trustline is AMM.
Browse files Browse the repository at this point in the history
  • Loading branch information
@gregtatcam
gregtatcam committed Nov 18, 2024
1 parent 52fec86 commit c35f056
Show file tree
Hide file tree
Showing 4 changed files with 102 additions and 93 deletions.
2 changes: 2 additions & 0 deletions include/xrpl/protocol/LedgerFormats.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -164,6 +164,8 @@ enum LedgerSpecificFlags {
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.
lsfLowAMMNode = 0x02000000, // True, the low side is AMM
lsfHighAMMNode = 0x04000000, // True, the high side is AMM

// ltSIGNER_LIST
lsfOneOwnerCount = 0x00010000, // True, uses only one OwnerCount
Expand Down
11 changes: 9 additions & 2 deletions src/xrpld/app/tx/detail/AMMCreate.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -327,8 +327,15 @@ applyCreate(
return tecINTERNAL;
else
{
auto const flags = sleRippleState->getFlags();
sleRippleState->setFieldU32(sfFlags, flags | lsfAMMNode);
std::uint32_t const flags = [&] {
auto const flags = sleRippleState->getFlags() | lsfAMMNode;
if (!sb.rules().enabled(fixAMMv1_3))
return flags;
if (*ammAccount > amount.get<Issue>().account)
return flags | lsfHighAMMNode;
return flags | lsfLowAMMNode;
}();
sleRippleState->setFieldU32(sfFlags, flags);
sb.update(sleRippleState);
}
}
Expand Down
165 changes: 74 additions & 91 deletions src/xrpld/app/tx/detail/InvariantCheck.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1132,31 +1132,29 @@ ValidAMM::visitEntry(
return;

using Balance = hash_map<AccountID, hash_map<Issue, STAmount>>;
auto set = [&](SLE const& sle,
Balance& balance,
STAmount const& a1,
STAmount const& a2) {
STAmount assetBalance = sle[sfBalance];
// don't know account/issuer
if (assetBalance.negative())
assetBalance.negate();
// Don't know which side of the trustline is AMM so save both.
// finalize() does lookup to figure out the AMM side.
balance[a1.getIssuer()][a2.get<Issue>()] = assetBalance;
balance[a2.getIssuer()][a1.get<Issue>()] = assetBalance;
};
auto update = [&](SLE const& sle, Balance& balance) {
auto const leType = sle.getType();
auto const flags = sle.getFlags();
if (leType == ltACCOUNT_ROOT && sle.isFieldPresent(sfAMMID))
{
balance[sle[sfAccount]][xrpIssue()] = sle[sfBalance];
}
else if (leType == ltRIPPLE_STATE && (sle.getFlags() & lsfAMMNode))
else if (
leType == ltRIPPLE_STATE &&
(flags & (lsfLowAMMNode | lsfHighAMMNode)))
{
STAmount assetBalance = sle[sfBalance];
auto const& highLimit = sle.getFieldAmount(sfHighLimit);
auto const& lowLimit = sle.getFieldAmount(sfLowLimit);
set(sle, balance, highLimit, lowLimit);
set(sle, balance, lowLimit, highLimit);
if (flags & lsfHighAMMNode)
{
assetBalance.negate();
balance[highLimit.getIssuer()][lowLimit.get<Issue>()] =
assetBalance;
}
else
balance[lowLimit.getIssuer()][highLimit.get<Issue>()] =
assetBalance;
}
};

Expand Down Expand Up @@ -1260,89 +1258,74 @@ ValidAMM::finalize(
txType == ttPAYMENT || txType == ttOFFER_CREATE ||
txType == ttCHECK_CASH)
{
if (balanceBefore_.size() != balanceAfter_.size())
return false;
for (auto const& [k, v] : balanceBefore_)
for (auto const& [ammAccount, assets] : balanceBefore_)
{
if (auto const root = _view.read(keylet::account(k));
root && root->isFieldPresent(sfAMMID))
static Issue iss{};
auto it = assets.cbegin();
auto const& asset = it->first;
auto const& asset2 = (++it) != assets.end() ? it->first : iss;
// AMM must have two balances - one for each pool side
if (assets.size() != 2 || !balanceAfter_.contains(ammAccount) ||
!balanceAfter_[ammAccount].contains(asset) ||
!balanceAfter_[ammAccount].contains(asset2))
{
std::uint16_t tfee = 0;
STAmount lptAMMBalance{};
if (auto const amm =
_view.read(keylet::amm((*root)[sfAMMID]));
amm && (*amm)[sfLPTokenBalance] <= beast::zero)
{
// LCOV_EXCL_START
JLOG(j.error())
<< "AMM swap invariant failed: invalid token "
"balance "
<< to_string(k) << " " << (*amm)[sfLPTokenBalance];
return false;
// LCOV_EXCL_STOP
}
else
{
tfee = (*amm)[sfTradingFee];
lptAMMBalance = (*amm)[sfLPTokenBalance];
}
// AMM must have two balances - one for each pool side
if (!balanceAfter_.contains(k) || v.size() != 2)
{
JLOG(j.error())
<< "AMM swap invariant failed: inconsistent assets "
<< to_string(k) << " " << v.size();
return false;
}
auto it = v.begin();
auto const asset = it->first;
auto const asset2 = (++it)->first;
if (!balanceAfter_[k].contains(asset) ||
!balanceAfter_[k].contains(asset2))
{
JLOG(j.error())
<< "AMM swap invariant failed: inconsistent assets "
<< to_string(k) << " " << asset << " " << asset2;
return false;
}
auto const ammKeylet = keylet::amm(asset, asset2);
if (_view.exists(ammKeylet))
JLOG(j.error())
<< "AMM swap invariant failed: inconsistent assets "
<< to_string(ammAccount) << " " << assets.size() << " "
<< asset << " " << asset2;
return false;
}
if (auto const amm = _view.read(keylet::amm(asset, asset2)))
{
auto const lptAMMBalance = (*amm)[sfLPTokenBalance];
auto const tfee = (*amm)[sfTradingFee];
Number const productBefore =
balanceBefore_[ammAccount][asset] *
balanceBefore_[ammAccount][asset2];
auto const amount = balanceAfter_[ammAccount][asset];
auto const amount2 = balanceAfter_[ammAccount][asset2];
Number const productAfter = amount * amount2;
if (positiveBalances(
amount, amount2, lptAMMBalance, false) &&
(productAfter >= productBefore ||
withinRelativeDistance(
productBefore, productAfter, Number{1, -7})))
{
Number const productBefore = balanceBefore_[k][asset] *
balanceBefore_[k][asset2];
auto const amount = balanceAfter_[k][asset];
auto const amount2 = balanceAfter_[k][asset2];
Number const productAfter = amount * amount2;
if (positiveBalances(
amount, amount2, lptAMMBalance, false) &&
(productAfter >= productBefore ||
withinRelativeDistance(
productBefore, productAfter, Number{1, -7})))
return true;

JLOG(j.error())
<< "AMM swap invariant failed: old balances "
<< balanceBefore_[k][asset].getText() << " "
<< balanceBefore_[k][asset2].getText()
<< " new balances "
<< balanceAfter_[k][asset].getText() << " "
<< balanceAfter_[k][asset2].getText()
<< " lptAMMBalance " << lptAMMBalance << " tfee "
<< tfee << " old/new product " << productBefore
<< " " << productAfter << " diff "
<< (productBefore != Number{0}
? to_string(
(productBefore - productAfter) /
productBefore)
: "undefined")
<< std::endl;
return false;
balanceAfter_.erase(ammAccount);
continue;
}

JLOG(j.error())
<< "AMM swap invariant failed: old balances "
<< balanceBefore_[ammAccount][asset].getText() << " "
<< balanceBefore_[ammAccount][asset2].getText()
<< " new balances "
<< balanceAfter_[ammAccount][asset].getText() << " "
<< balanceAfter_[ammAccount][asset2].getText()
<< " lptAMMBalance " << lptAMMBalance << " tfee "
<< tfee << " diff "
<< (productBefore != Number{0}
? to_string(
(productBefore - productAfter) /
productBefore)
: "undefined")
<< std::endl;
return false;
}
else
{
JLOG(j.error())
<< "AMM swap invariant failed: amm is not found "
<< asset << " " << asset2;
return false;
}
balanceAfter_.erase(k);
}
if (!balanceAfter_.empty())
{
JLOG(j.error())
<< "AMM swap invariant failed: inconsistent before/after";
return false;
}
}
}

Expand Down
17 changes: 17 additions & 0 deletions src/xrpld/ledger/detail/View.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1144,6 +1144,23 @@ rippleCreditIOU(
j);
}

if (view.rules().enabled(fixAMMv1_3) && (uFlags & lsfAMMNode) &&
!(uFlags & (lsfHighAMMNode | lsfLowAMMNode)))
{
auto const sleSender = view.read(keylet::account(uSenderID));
if (!sleSender)
return tefINTERNAL;
if (sleSender->isFieldPresent(sfAMMID))
{
auto const flags = sleRippleState->getFlags();
if (uSenderID > uReceiverID)
sleRippleState->setFieldU32(
sfFlags, flags | lsfHighAMMNode);
else
sleRippleState->setFieldU32(sfFlags, flags | lsfLowAMMNode);
}
}

view.update(sleRippleState);
return tesSUCCESS;
}
Expand Down

0 comments on commit c35f056

Please sign in to comment.