Interpret fee amount parameters in reference fee unit (#15)

* Interpret minrelaytxfee in abstract reference fee unit

* Interpret maxtxfee in abstract reference fee unit

* Remove erroneous exchange rate conversions

* Bugfix: get fee asset from transaction rather than non-existent mem pool entry

This reverts commit 4a6152b.

---------

Co-authored-by: Mihailo Milenkovic <[email protected]>

Author: JBetz

src/node/transaction.cpp

@@ -4,6 +4,7 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <consensus/validation.h>
+#include <exchangerates.h>
 #include <index/txindex.h>
 #include <net.h>
 #include <net_processing.h>
@@ -74,6 +75,11 @@ TransactionError BroadcastTransaction(NodeContext& node, const CTransactionRef t
                 const MempoolAcceptResult result = node.chainman->ProcessTransaction(tx, /*test_accept=*/ true);
                 if (result.m_result_type != MempoolAcceptResult::ResultType::VALID) {
                     return HandleATMPError(result.m_state, err_string);
+                } else if (g_con_any_asset_fees) {
+                    CAmount mBaseFeesValue = ExchangeRateMap::GetInstance().CalculateExchangeValue(result.m_base_fees.value(), tx->GetFeeAsset(::policyAsset));
+                    if (mBaseFeesValue > max_tx_fee) {
+                        return TransactionError::MAX_FEE_EXCEEDED;
+                    }
                 } else if (result.m_base_fees.value() > max_tx_fee) {
                     return TransactionError::MAX_FEE_EXCEEDED;
                 }

src/primitives/transaction.h

@@ -580,6 +580,17 @@ class CTransaction
     {
         return !witness.IsNull();
     }
+
+    const CAsset& GetFeeAsset(CAsset& default_asset) const 
+    {
+        CAsset& feeAsset = default_asset;
+        for (size_t i = 0; i < vout.size(); i++) {
+            if (vout[i].IsFee()) { 
+                feeAsset = vout[i].nAsset.GetAsset();
+            }
+        }
+        return feeAsset;
+    }
 };
 
 /** A mutable version of CTransaction. */

src/validation.cpp

@@ -926,7 +926,11 @@ bool MemPoolAccept::PreChecks(ATMPArgs& args, Workspace& ws)
 
     // No transactions are allowed below minRelayTxFee except from disconnected
     // blocks
-    if (!bypass_limits && !CheckFeeRate(ws.m_vsize, ws.m_modified_fees, state)) return false;
+    CAmount totalFees = ws.m_modified_fees;
+    if (g_con_any_asset_fees) {
+        totalFees = ExchangeRateMap::GetInstance().CalculateExchangeValue(totalFees, feeAsset);
+    }
+    if (!bypass_limits && !CheckFeeRate(ws.m_vsize, totalFees, state)) return false;
 
     ws.m_iters_conflicting = m_pool.GetIterSet(ws.m_conflicts);
     // Calculate in-mempool ancestors, up to a limit.

src/wallet/spend.cpp

@@ -5,6 +5,7 @@
 #include <blind.h> // ELEMENTS: for MAX_RANGEPROOF_SIZE
 #include <consensus/amount.h>
 #include <consensus/validation.h>
+#include <exchangerates.h>
 #include <interfaces/chain.h>
 #include <issuance.h> // ELEMENTS: for GenerateAssetEntropy and others
 #include <policy/policy.h>
@@ -1691,7 +1692,14 @@ static bool CreateTransactionInternal(
         return false;
     }
 
-    if (nFeeRet > wallet.m_default_max_tx_fee) {
+    if (g_con_any_asset_fees) {
+        ExchangeRateMap& exchangeRateMap = ExchangeRateMap::GetInstance();
+        CAmount nFeeRetValue = exchangeRateMap.CalculateExchangeValue(nFeeRet, coin_selection_params.m_fee_asset); 
+        if (nFeeRetValue > wallet.m_default_max_tx_fee) {
+            error = TransactionErrorString(TransactionError::MAX_FEE_EXCEEDED);
+            return false;
+        }
+    } else if (nFeeRet > wallet.m_default_max_tx_fee) {
         error = TransactionErrorString(TransactionError::MAX_FEE_EXCEEDED);
         return false;
     }