Merge #13557: BIP 174 PSBT Serializations and RPCs

020628e Tests for PSBT (Andrew Chow)
a4b06fb Create wallet RPCs for PSBT (Andrew Chow)
c27fe41 Create utility RPCs for PSBT (Andrew Chow)
8b5ef27 SignPSBTInput wrapper function (Andrew Chow)
58a8e28 Refactor transaction creation and transaction funding logic (Andrew Chow)
e9d86a4 Methods for interacting with PSBT structs (Andrew Chow)
12bcc64 Add pubkeys and whether input was witness to SignatureData (Andrew Chow)
41c607f Implement PSBT Structures and un/serialization methods per BIP 174 (Andrew Chow)

Pull request description:

  This Pull Request fully implements the [updated](bitcoin/bips#694) BIP 174 specification. It is based upon #13425 which implements the majority of the signing logic.

  BIP 174 specifies a binary transaction format which contains the information necessary for a signer to produce signatures for the transaction and holds the signatures for an input while the input does not have a complete set of signatures.

  This PR contains structs for PSBT, serialization, and deserialzation code. Some changes to `SignatureData` have been made to support detection of UTXO type and storing public keys.

  ***

  Many RPCs have been added to handle PSBTs.

  `walletprocesspsbt` takes a PSBT format transaction, updates the PSBT with any inputs related to this wallet, signs, and finalizes the transaction. There is also an option to not sign and just update.

  `walletcreatefundedpsbt` creates a PSBT from user provided data in the same form as createrawtransaction. It also funds the transaction and takes an options argument in the same form as `fundrawtransaction`. The resulting PSBT is blank with no input or output data filled in. It is analogous to a combination of `createrawtransaction` and `fundrawtransaction`

  `decodepsbt` takes a PSBT and decodes it to JSON. It is analogous to `decoderawtransaction`

  `combinepsbt` takes multiple PSBTs for the same tx and combines them. It is analogous to `combinerawtransaction`

  `finalizepsbt` takes a PSBT and finalizes the inputs. If all inputs are final, it extracts the network serialized transaction and returns that instead of a PSBT unless instructed otherwise.

  `createpsbt` is like `createrawtransaction` but for PSBTs instead of raw transactions.

  `convertpsbt` takes a network serialized transaction and converts it into a psbt. The resulting psbt will lose all signature data and an explicit flag must be set to allow transactions with signature data to be converted.

  ***

  This supersedes #12136

Tree-SHA512: 1ac7a79e5bc669933f0a6fcc93ded55263fdde9e8c144a30266b13ef9f62aacf43edd4cbca1ffbe003090b067e9643c9298c79be69d7c1b10231b32acafb6338

Author: laanwj

src/Makefile.test.include

@@ -94,6 +94,7 @@ BITCOIN_TESTS =\
 if ENABLE_WALLET
 BITCOIN_TESTS += \
   wallet/test/accounting_tests.cpp \
+  wallet/test/psbt_wallet_tests.cpp \
   wallet/test/wallet_tests.cpp \
   wallet/test/wallet_crypto_tests.cpp \
   wallet/test/coinselector_tests.cpp

src/core_io.h

@@ -14,6 +14,7 @@ class CBlock;
 class CScript;
 class CTransaction;
 struct CMutableTransaction;
+struct PartiallySignedTransaction;
 class uint256;
 class UniValue;
 
@@ -24,12 +25,16 @@ bool DecodeHexTx(CMutableTransaction& tx, const std::string& hex_tx, bool try_no
 bool DecodeHexBlk(CBlock&, const std::string& strHexBlk);
 uint256 ParseHashStr(const std::string&, const std::string& strName);
 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);
 
 // core_write.cpp
 UniValue ValueFromAmount(const CAmount& amount);
 std::string FormatScript(const CScript& script);
 std::string EncodeHexTx(const CTransaction& tx, const int serializeFlags = 0);
+std::string SighashToStr(unsigned char sighash_type);
 void ScriptPubKeyToUniv(const CScript& scriptPubKey, UniValue& out, bool fIncludeHex);
+void ScriptToUniv(const CScript& script, UniValue& out, bool include_address);
 void TxToUniv(const CTransaction& tx, const uint256& hashBlock, UniValue& entry, bool include_hex = true, int serialize_flags = 0);
 
 #endif // BITCOIN_CORE_IO_H

src/core_read.cpp

@@ -7,6 +7,7 @@
 #include <primitives/block.h>
 #include <primitives/transaction.h>
 #include <script/script.h>
+#include <script/sign.h>
 #include <serialize.h>
 #include <streams.h>
 #include <univalue.h>
@@ -160,6 +161,23 @@ bool DecodeHexBlk(CBlock& block, const std::string& strHexBlk)
     return true;
 }
 
+bool DecodePSBT(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);
+    try {
+        ss_data >> psbt;
+        if (!ss_data.empty()) {
+            error = "extra data after PSBT";
+            return false;
+        }
+    } catch (const std::exception& e) {
+        error = e.what();
+        return false;
+    }
+    return true;
+}
+
 uint256 ParseHashStr(const std::string& strHex, const std::string& strName)
 {
     if (!IsHex(strHex)) // Note: IsHex("") is false
@@ -179,3 +197,26 @@ std::vector<unsigned char> ParseHexUV(const UniValue& v, const std::string& strN
         throw std::runtime_error(strName + " must be hexadecimal string (not '" + strHex + "')");
     return ParseHex(strHex);
 }
+
+int ParseSighashString(const UniValue& sighash)
+{
+    int hash_type = SIGHASH_ALL;
+    if (!sighash.isNull()) {
+        static std::map<std::string, int> map_sighash_values = {
+            {std::string("ALL"), int(SIGHASH_ALL)},
+            {std::string("ALL|ANYONECANPAY"), int(SIGHASH_ALL|SIGHASH_ANYONECANPAY)},
+            {std::string("NONE"), int(SIGHASH_NONE)},
+            {std::string("NONE|ANYONECANPAY"), int(SIGHASH_NONE|SIGHASH_ANYONECANPAY)},
+            {std::string("SINGLE"), int(SIGHASH_SINGLE)},
+            {std::string("SINGLE|ANYONECANPAY"), int(SIGHASH_SINGLE|SIGHASH_ANYONECANPAY)},
+        };
+        std::string strHashType = sighash.get_str();
+        const auto& it = map_sighash_values.find(strHashType);
+        if (it != map_sighash_values.end()) {
+            hash_type = it->second;
+        } else {
+            throw std::runtime_error(strHashType + " is not a valid sighash parameter.");
+        }
+    }
+    return hash_type;
+}

src/core_write.cpp

@@ -70,6 +70,13 @@ const std::map<unsigned char, std::string> mapSigHashTypes = {
     {static_cast<unsigned char>(SIGHASH_SINGLE|SIGHASH_ANYONECANPAY), std::string("SINGLE|ANYONECANPAY")},
 };
 
+std::string SighashToStr(unsigned char sighash_type)
+{
+    const auto& it = mapSigHashTypes.find(sighash_type);
+    if (it == mapSigHashTypes.end()) return "";
+    return it->second;
+}
+
 /**
  * Create the assembly string representation of a CScript object.
  * @param[in] script    CScript object to convert into the asm string representation.
@@ -128,6 +135,22 @@ std::string EncodeHexTx(const CTransaction& tx, const int serializeFlags)
     return HexStr(ssTx.begin(), ssTx.end());
 }
 
+void ScriptToUniv(const CScript& script, UniValue& out, bool include_address)
+{
+    out.pushKV("asm", ScriptToAsmStr(script));
+    out.pushKV("hex", HexStr(script.begin(), script.end()));
+
+    std::vector<std::vector<unsigned char>> solns;
+    txnouttype type;
+    Solver(script, type, solns);
+    out.pushKV("type", GetTxnOutputType(type));
+
+    CTxDestination address;
+    if (include_address && ExtractDestination(script, address)) {
+        out.pushKV("address", EncodeDestination(address));
+    }
+}
+
 void ScriptPubKeyToUniv(const CScript& scriptPubKey,
                         UniValue& out, bool fIncludeHex)
 {

src/pubkey.h

@@ -107,6 +107,7 @@ class CPubKey
 
     //! Simple read-only vector-like interface to the pubkey data.
     unsigned int size() const { return GetLen(vch[0]); }
+    const unsigned char* data() const { return vch; }
     const unsigned char* begin() const { return vch; }
     const unsigned char* end() const { return vch + size(); }
     const unsigned char& operator[](unsigned int pos) const { return vch[pos]; }

src/rpc/client.cpp

@@ -110,6 +110,22 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "combinerawtransaction", 0, "txs" },
     { "fundrawtransaction", 1, "options" },
     { "fundrawtransaction", 2, "iswitness" },
+    { "walletcreatefundedpsbt", 0, "inputs" },
+    { "walletcreatefundedpsbt", 1, "outputs" },
+    { "walletcreatefundedpsbt", 2, "locktime" },
+    { "walletcreatefundedpsbt", 3, "replaceable" },
+    { "walletcreatefundedpsbt", 4, "options" },
+    { "walletcreatefundedpsbt", 5, "bip32derivs" },
+    { "walletprocesspsbt", 1, "sign" },
+    { "walletprocesspsbt", 3, "bip32derivs" },
+    { "createpsbt", 0, "inputs" },
+    { "createpsbt", 1, "outputs" },
+    { "createpsbt", 2, "locktime" },
+    { "createpsbt", 3, "replaceable" },
+    { "combinepsbt", 0, "txs"},
+    { "finalizepsbt", 1, "extract"},
+    { "converttopsbt", 1, "permitsigdata"},
+    { "converttopsbt", 2, "iswitness"},
     { "gettxout", 1, "n" },
     { "gettxout", 2, "include_mempool" },
     { "gettxoutproof", 0, "txids" },