merge bitcoin#14978: Factor out PSBT utilities from RPCs for use in GUI code; related refactoring

Author: kwvg

src/Makefile.am

@@ -231,6 +231,7 @@ BITCOIN_CORE_H = \
   policy/policy.h \
   pow.h \
   protocol.h \
+  psbt.h \
   random.h \
   reverse_iterator.h \
   rpc/blockchain.h \
@@ -293,6 +294,7 @@ BITCOIN_CORE_H = \
   wallet/crypter.h \
   wallet/db.h \
   wallet/fees.h \
+  wallet/psbtwallet.h \
   wallet/rpcwallet.h \
   wallet/wallet.h \
   wallet/walletdb.h \
@@ -441,6 +443,7 @@ libcosanta_wallet_a_SOURCES = \
   wallet/db.cpp \
   wallet/fees.cpp \
   wallet/init.cpp \
+  wallet/psbtwallet.cpp \
   wallet/rpcdump.cpp \
   wallet/rpcwallet.cpp \
   wallet/wallet.cpp \
@@ -602,6 +605,7 @@ libcosanta_common_a_SOURCES = \
   netbase.cpp \
   net_permissions.cpp \
   policy/feerate.cpp \
+  psbt.cpp \
   protocol.cpp \
   saltedhasher.cpp \
   scheduler.cpp \

src/core_io.h

@@ -39,9 +39,13 @@ bool DecodeHexBlockHeader(CBlockHeader&, const std::string& hex_header);
  */
 bool ParseHashStr(const std::string& strHex, uint256& result);
 std::vector<unsigned char> ParseHexUV(const UniValue& v, const std::string& strName);
-bool DecodePSBT(PartiallySignedTransaction& psbt, const std::string& base64_tx, std::string& error);
 int ParseSighashString(const UniValue& sighash);
 
+//! Decode a base64ed PSBT into a PartiallySignedTransaction
+[[nodiscard]] bool DecodeBase64PSBT(PartiallySignedTransaction& decoded_psbt, const std::string& base64_psbt, std::string& error);
+//! Decode a raw (binary blob) PSBT into a PartiallySignedTransaction
+[[nodiscard]] bool DecodeRawPSBT(PartiallySignedTransaction& decoded_psbt, const std::string& raw_psbt, std::string& error);
+
 // core_write.cpp
 UniValue ValueFromAmount(const CAmount& amount);
 std::string FormatScript(const CScript& script);

src/core_read.cpp

@@ -5,6 +5,7 @@
 
 #include <core_io.h>
 
+#include <psbt.h>
 #include <primitives/block.h>
 #include <primitives/transaction.h>
 #include <script/script.h>
@@ -140,10 +141,20 @@ bool DecodeHexBlk(CBlock& block, const std::string& strHexBlk)
     return true;
 }
 
-bool DecodePSBT(PartiallySignedTransaction& psbt, const std::string& base64_tx, std::string& error)
+bool DecodeBase64PSBT(PartiallySignedTransaction& psbt, const std::string& base64_tx, std::string& error)
 {
-    std::vector<unsigned char> tx_data = DecodeBase64(base64_tx.c_str());
-    CDataStream ss_data(tx_data, SER_NETWORK, PROTOCOL_VERSION);
+    bool invalid;
+    std::string tx_data = DecodeBase64(base64_tx, &invalid);
+    if (invalid) {
+        error = "invalid base64";
+        return false;
+    }
+    return DecodeRawPSBT(psbt, tx_data, error);
+}
+
+bool DecodeRawPSBT(PartiallySignedTransaction& psbt, const std::string& tx_data, std::string& error)
+{
+    CDataStream ss_data(tx_data.data(), tx_data.data() + tx_data.size(), SER_NETWORK, PROTOCOL_VERSION);
     try {
         ss_data >> psbt;
         if (!ss_data.empty()) {

src/node/transaction.cpp

@@ -5,7 +5,6 @@
 
 #include <consensus/validation.h>
 #include <net.h>
-#include <rpc/server.h>
 #include <txmempool.h>
 #include <validation.h>
 #include <validationinterface.h>
@@ -14,9 +13,38 @@
 
 #include <future>
 
-uint256 BroadcastTransaction(const CTransactionRef tx, const bool allowhighfees) {
+const char* TransactionErrorString(const TransactionError err)
+{
+    switch (err) {
+        case TransactionError::OK:
+            return "No error";
+        case TransactionError::MISSING_INPUTS:
+            return "Missing inputs";
+        case TransactionError::ALREADY_IN_CHAIN:
+            return "Transaction already in block chain";
+        case TransactionError::P2P_DISABLED:
+            return "Peer-to-peer functionality missing or disabled";
+        case TransactionError::MEMPOOL_REJECTED:
+            return "Transaction rejected by AcceptToMemoryPool";
+        case TransactionError::MEMPOOL_ERROR:
+            return "AcceptToMemoryPool failed";
+        case TransactionError::INVALID_PSBT:
+            return "PSBT is not sane";
+        case TransactionError::PSBT_MISMATCH:
+            return "PSBTs not compatible (different transactions)";
+        case TransactionError::SIGHASH_MISMATCH:
+            return "Specified sighash value does not match existing value";
+
+        case TransactionError::UNKNOWN_ERROR:
+        default: break;
+    }
+    return "Unknown error";
+}
+
+bool BroadcastTransaction(const CTransactionRef tx, uint256& hashTx, TransactionError& error, std::string& err_string, const bool allowhighfees, const bool bypass_limits)
+{
     std::promise<void> promise;
-    const uint256& hashTx = tx->GetHash();
+    hashTx = tx->GetHash();
 
     CAmount nMaxRawTxFee = maxTxFee;
     if (allowhighfees)
@@ -36,14 +64,19 @@ uint256 BroadcastTransaction(const CTransactionRef tx, const bool allowhighfees)
         CValidationState state;
         bool fMissingInputs;
         if (!AcceptToMemoryPool(mempool, state, std::move(tx), &fMissingInputs,
-                                false /* plTxnReplaced */, false /* bypass_limits */, nMaxRawTxFee)) {
+                                bypass_limits, nMaxRawTxFee)) {
             if (state.IsInvalid()) {
-                throw JSONRPCError(RPC_TRANSACTION_REJECTED, FormatStateMessage(state));
+                err_string = FormatStateMessage(state);
+                error = TransactionError::MEMPOOL_REJECTED;
+                return false;
             } else {
                 if (fMissingInputs) {
-                    throw JSONRPCError(RPC_TRANSACTION_ERROR, "Missing inputs");
+                    error = TransactionError::MISSING_INPUTS;
+                    return false;
                 }
-                throw JSONRPCError(RPC_TRANSACTION_ERROR, FormatStateMessage(state));
+                err_string = FormatStateMessage(state);
+                error = TransactionError::MEMPOOL_ERROR;
+                return false;
             }
         } else {
             // If wallet is enabled, ensure that the wallet has been made aware
@@ -56,7 +89,8 @@ uint256 BroadcastTransaction(const CTransactionRef tx, const bool allowhighfees)
             });
         }
     } else if (fHaveChain) {
-        throw JSONRPCError(RPC_TRANSACTION_ALREADY_IN_CHAIN, "transaction already in block chain");
+        error = TransactionError::ALREADY_IN_CHAIN;
+        return false;
     } else {
         // Make sure we don't block forever if re-sending
         // a transaction already in mempool.
@@ -67,10 +101,12 @@ uint256 BroadcastTransaction(const CTransactionRef tx, const bool allowhighfees)
 
     promise.get_future().wait();
 
-    if(!g_connman)
-        throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
+    if(!g_connman) {
+        error = TransactionError::P2P_DISABLED;
+        return false;
+    }
 
     g_connman->RelayTransaction(*tx);
 
-    return hashTx;
-}
+    return true;
+    }

src/node/transaction.h

@@ -8,7 +8,36 @@
 #include <primitives/transaction.h>
 #include <uint256.h>
 
-/** Broadcast a transaction */
-uint256 BroadcastTransaction(CTransactionRef tx, bool allowhighfees = false);
+enum class TransactionError {
+    OK = 0,
+    UNKNOWN_ERROR,
+
+    MISSING_INPUTS,
+    ALREADY_IN_CHAIN,
+    P2P_DISABLED,
+    MEMPOOL_REJECTED,
+    MEMPOOL_ERROR,
+    INVALID_PSBT,
+    PSBT_MISMATCH,
+    SIGHASH_MISMATCH,
+
+    ERROR_COUNT
+};
+
+#define TRANSACTION_ERR_LAST TransactionError::ERROR_COUNT
+
+const char* TransactionErrorString(const TransactionError error);
+
+/**
+ * Broadcast a transaction
+ *
+ * @param[in]  tx the transaction to broadcast
+ * @param[out] &txid the txid of the transaction, if successfully broadcast
+ * @param[out] &error reference to UniValue to fill with error info on failure
+ * @param[out] &err_string reference to std::string to fill with error string if available
+ * @param[in]  allowhighfees whether to allow fees exceeding maxTxFee
+ * return true on success, false on error (and fills in `error`)
+ */
+bool BroadcastTransaction(const CTransactionRef tx, uint256& txid, TransactionError& error, std::string& err_string, const bool allowhighfees = false, const bool bypass_limits = false);
 
 #endif // BITCOIN_NODE_TRANSACTION_H