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

102faad Factor out combine / finalize / extract PSBT helpers (Glenn Willen)
78b9893 Remove op== on PSBTs; check compatibility in Merge (Glenn Willen)
bd0dbe8 Switch away from exceptions in refactored tx code (Glenn Willen)
c6c3d42 Move PSBT definitions and code to separate files (Glenn Willen)
81cd958 Factor BroadcastTransaction out of sendrawtransaction (Glenn Willen)
c734aaa Split DecodePSBT into Base64 and Raw versions (Glenn Willen)
162ffef Add pf_invalid arg to std::string DecodeBase{32,64} (Glenn Willen)

Pull request description:

  * Move most PSBT definitions into psbt.h.
  * Move most PSBT RPC utilities into psbt.{h,cpp}.
  * Move wallet-touching PSBT RPC utilities (FillPSBT) into
      wallet/psbtwallet.{h,cpp}.
  * Switch exceptions from JSONRPCError() to new PSBTException class.
  * Split DecodePSBT into DecodeBase64PSBT (old behavior) and DecodeRawPSBT.
  * Add one new version of DecodeBase64 utility in strencodings.h (and
      corresponding DecodeBase32 for completeness).
  * Factor BroadcastTransaction utility function out of sendrawtransaction RPC
      handler in rpc/rawtransaction.cpp

  Note: For those keeping score at home wondering why refactor, this is in anticipation of (and developed in parallel with) a change to actually introduce GUI use of all this stuff, which is already under development and working-ish.

Tree-SHA512: 2197c448e657421f430943025357597e7b06c4c377d5d4b2622b9edea52a7193c48843dd731abb3a88ac4023a9c88d211991e0a9b740c22f2e1cbe72adefe390

Author: meshcollider

src/Makefile.am

@@ -152,6 +152,7 @@ BITCOIN_CORE_H = \
   netaddress.h \
   netbase.h \
   netmessagemaker.h \
+  node/transaction.h \
   noui.h \
   optional.h \
   outputtype.h \
@@ -161,6 +162,7 @@ BITCOIN_CORE_H = \
   policy/rbf.h \
   pow.h \
   protocol.h \
+  psbt.h \
   random.h \
   reverse_iterator.h \
   reverselock.h \
@@ -209,6 +211,7 @@ BITCOIN_CORE_H = \
   wallet/db.h \
   wallet/feebumper.h \
   wallet/fees.h \
+  wallet/psbtwallet.h \
   wallet/rpcwallet.h \
   wallet/wallet.h \
   wallet/walletdb.h \
@@ -255,6 +258,7 @@ libbitcoin_server_a_SOURCES = \
   miner.cpp \
   net.cpp \
   net_processing.cpp \
+  node/transaction.cpp \
   noui.cpp \
   outputtype.cpp \
   policy/fees.cpp \
@@ -308,6 +312,7 @@ libbitcoin_wallet_a_SOURCES = \
   wallet/feebumper.cpp \
   wallet/fees.cpp \
   wallet/init.cpp \
+  wallet/psbtwallet.cpp \
   wallet/rpcdump.cpp \
   wallet/rpcwallet.cpp \
   wallet/wallet.cpp \
@@ -421,6 +426,7 @@ libbitcoin_common_a_SOURCES = \
   netaddress.cpp \
   netbase.cpp \
   policy/feerate.cpp \
+  psbt.cpp \
   protocol.cpp \
   scheduler.cpp \
   script/descriptor.cpp \

src/core_io.h

@@ -37,7 +37,11 @@ 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);
-NODISCARD bool DecodePSBT(PartiallySignedTransaction& psbt, const std::string& base64_tx, std::string& error);
+
+//! 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);
 int ParseSighashString(const UniValue& sighash);
 
 // core_write.cpp

src/core_read.cpp

@@ -4,6 +4,7 @@
 
 #include <core_io.h>
 
+#include <psbt.h>
 #include <primitives/block.h>
 #include <primitives/transaction.h>
 #include <script/script.h>
@@ -176,10 +177,20 @@ 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

@@ -0,0 +1,115 @@
+// Copyright (c) 2010 Satoshi Nakamoto
+// Copyright (c) 2009-2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <consensus/validation.h>
+#include <net.h>
+#include <txmempool.h>
+#include <validation.h>
+#include <validationinterface.h>
+#include <node/transaction.h>
+
+#include <future>
+
+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)
+{
+    std::promise<void> promise;
+    hashTx = tx->GetHash();
+
+    CAmount nMaxRawTxFee = maxTxFee;
+    if (allowhighfees)
+        nMaxRawTxFee = 0;
+
+    { // cs_main scope
+    LOCK(cs_main);
+    CCoinsViewCache &view = *pcoinsTip;
+    bool fHaveChain = false;
+    for (size_t o = 0; !fHaveChain && o < tx->vout.size(); o++) {
+        const Coin& existingCoin = view.AccessCoin(COutPoint(hashTx, o));
+        fHaveChain = !existingCoin.IsSpent();
+    }
+    bool fHaveMempool = mempool.exists(hashTx);
+    if (!fHaveMempool && !fHaveChain) {
+        // push to local node and sync with wallets
+        CValidationState state;
+        bool fMissingInputs;
+        if (!AcceptToMemoryPool(mempool, state, std::move(tx), &fMissingInputs,
+                                nullptr /* plTxnReplaced */, false /* bypass_limits */, nMaxRawTxFee)) {
+            if (state.IsInvalid()) {
+                err_string = FormatStateMessage(state);
+                error = TransactionError::MEMPOOL_REJECTED;
+                return false;
+            } else {
+                if (fMissingInputs) {
+                    error = TransactionError::MISSING_INPUTS;
+                    return false;
+                }
+                err_string = FormatStateMessage(state);
+                error = TransactionError::MEMPOOL_ERROR;
+                return false;
+            }
+        } else {
+            // If wallet is enabled, ensure that the wallet has been made aware
+            // of the new transaction prior to returning. This prevents a race
+            // where a user might call sendrawtransaction with a transaction
+            // to/from their wallet, immediately call some wallet RPC, and get
+            // a stale result because callbacks have not yet been processed.
+            CallFunctionInValidationInterfaceQueue([&promise] {
+                promise.set_value();
+            });
+        }
+    } else if (fHaveChain) {
+        error = TransactionError::ALREADY_IN_CHAIN;
+        return false;
+    } else {
+        // Make sure we don't block forever if re-sending
+        // a transaction already in mempool.
+        promise.set_value();
+    }
+
+    } // cs_main
+
+    promise.get_future().wait();
+
+    if(!g_connman) {
+        error = TransactionError::P2P_DISABLED;
+        return false;
+    }
+
+    CInv inv(MSG_TX, hashTx);
+    g_connman->ForEachNode([&inv](CNode* pnode)
+    {
+        pnode->PushInventory(inv);
+    });
+
+    return true;
+    }

src/node/transaction.h

@@ -0,0 +1,43 @@
+// Copyright (c) 2017-2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_NODE_TRANSACTION_H
+#define BITCOIN_NODE_TRANSACTION_H
+
+#include <primitives/transaction.h>
+#include <uint256.h>
+
+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(CTransactionRef tx, uint256& txid, TransactionError& error, std::string& err_string, bool allowhighfees = false);
+
+#endif // BITCOIN_NODE_TRANSACTION_H