Merge bitcoin/bitcoin#17034: [BIP 174] PSBT version, proprietary, and xpub fields

81521173ba830ca1dea204e83897482f8970e519 Merge global xpubs in joinpsbts and combinepsbts (Andrew Chow)
d8043ddf640b1bb7a536834618c468334e3eb15f Add global xpub test vectors from BIP (Andrew Chow)
35670df866e0bb4a58a7cc032f7bcae508fd0273 Add global_xpubs to decodepsbt (Andrew Chow)
903848562ec5d8a167d24c5f5083695b2f104780 Implement serializations for PSBT_GLOBAL_XPUB (Andrew Chow)
c5c63b8e4f3fbdb6b5a423a39d6e318fecab991f Implement operator< for KeyOriginInfo and CExtPubKey (Andrew Chow)
d3dbb16168145ccbcc7ef0a8e150695711b661b7 Separate individual HD Keypath serialization into separate functions (Andrew Chow)
a69332fd89a5c1e293113b641fbe6b23cf279741 Store version bytes and be able to serialize them in CExtPubKey (Andrew Chow)
5fdaf6a2adbf99c4ab2c2863fba35a0baa559fb5 moveonly: Move (Un)Serialize(To/From)Vector, (De)SerializeHDKeypaths to psbt module (Andrew Chow)
94065cc6c5a087a5657519202a4ca08db7c1d861 Test for proprietary field (Andrew Chow)
a4cf8101746039ec8be234d899bdaf848548598e Output proprietary type info in decodepsbt (Andrew Chow)
aebe758e54802ead664a3c8b694fe0b447e01724 Implement PSBT proprietary type (Andrew Chow)
10ba0b593d3c9bc03e36d52344237be6e89c443f Output psbt version in decodepsbt (Andrew Chow)
df84fa99c5a52e4688e240c585f7d22b20401906 Add GetVersion helper to PSBT (Andrew Chow)
c3eb416b882522dffa4254b52d2da5b53c970efe Implement PSBT versions (Andrew Chow)
3235847473e36070cbe9b0e9deacdd8d8d9428fe Types are compact size uints (Andrew Chow)

Pull request description:

  Implements the changes to BIP 174 proposed in https://github.com/bitcoin/bips/pull/849 and https://github.com/bitcoin/bips/pull/784

  Implements `PSBT_GLOBAL_VERSION`, `PSBT_GLOBAL_PROPRIETARY`, `PSBT_IN_PROPRIETARY`, `PSBT_OUT_PROPRIETARY`, and `PSBT_GLOBAL_XPUB`. The `PSBT_GLOBAL_XPUB` changes are merged in from #16463.

  Also includes the test vectors added to BIP 174 for these fields.

  A number of additional changes to keypath and xpub serialization are made to support `PSBT_GLOBAL_XPUB`.

ACKs for top commit:
  laanwj:
    Code review ACK 81521173ba830ca1dea204e83897482f8970e519

Tree-SHA512: bd71c3f26030fc23824e76a30d3d346a753e1db224ecee163d6813348feb52d3f4cf4e739a4699e2cff381197ce2a7ea4a92a054f2c3e1db579e91e92a0945e0

1 files changed, 108 insertions, 0 deletions

diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 78c1596219..12ade466da 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -3,6 +3,7 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <base58.h>
 #include <chain.h>
 #include <coins.h>
 #include <consensus/amount.h>
@@ -1075,6 +1076,26 @@ static RPCHelpMan decodepsbt()
                         {
                             {RPCResult::Type::ELISION, "", "The layout is the same as the output of decoderawtransaction."},
                         }},
+                        {RPCResult::Type::ARR, "global_xpubs", "",
+                        {
+                            {RPCResult::Type::OBJ, "", "",
+                            {
+                                {RPCResult::Type::STR, "xpub", "The extended public key this path corresponds to"},
+                                {RPCResult::Type::STR_HEX, "master_fingerprint", "The fingerprint of the master key"},
+                                {RPCResult::Type::STR, "path", "The path"},
+                            }},
+                        }},
+                        {RPCResult::Type::NUM, "psbt_version", "The PSBT version number. Not to be confused with the unsigned transaction version"},
+                        {RPCResult::Type::ARR, "proprietary", "The global proprietary map",
+                        {
+                            {RPCResult::Type::OBJ, "", "",
+                            {
+                                {RPCResult::Type::STR_HEX, "identifier", "The hex string for the proprietary identifier"},
+                                {RPCResult::Type::NUM, "subtype", "The number for the subtype"},
+                                {RPCResult::Type::STR_HEX, "key", "The hex for the key"},
+                                {RPCResult::Type::STR_HEX, "value", "The hex for the value"},
+                            }},
+                        }},
                         {RPCResult::Type::OBJ_DYN, "unknown", "The unknown global fields",
                         {
                              {RPCResult::Type::STR_HEX, "key", "(key-value pair) An unknown key-value pair"},
@@ -1137,6 +1158,16 @@ static RPCHelpMan decodepsbt()
                                 {
                                     {RPCResult::Type::STR_HEX, "key", "(key-value pair) An unknown key-value pair"},
                                 }},
+                                {RPCResult::Type::ARR, "proprietary", "The input proprietary map",
+                                {
+                                    {RPCResult::Type::OBJ, "", "",
+                                    {
+                                        {RPCResult::Type::STR_HEX, "identifier", "The hex string for the proprietary identifier"},
+                                        {RPCResult::Type::NUM, "subtype", "The number for the subtype"},
+                                        {RPCResult::Type::STR_HEX, "key", "The hex for the key"},
+                                        {RPCResult::Type::STR_HEX, "value", "The hex for the value"},
+                                    }},
+                                }},
                             }},
                         }},
                         {RPCResult::Type::ARR, "outputs", "",
@@ -1168,6 +1199,16 @@ static RPCHelpMan decodepsbt()
                                 {
                                     {RPCResult::Type::STR_HEX, "key", "(key-value pair) An unknown key-value pair"},
                                 }},
+                                {RPCResult::Type::ARR, "proprietary", "The output proprietary map",
+                                {
+                                    {RPCResult::Type::OBJ, "", "",
+                                    {
+                                        {RPCResult::Type::STR_HEX, "identifier", "The hex string for the proprietary identifier"},
+                                        {RPCResult::Type::NUM, "subtype", "The number for the subtype"},
+                                        {RPCResult::Type::STR_HEX, "key", "The hex for the key"},
+                                        {RPCResult::Type::STR_HEX, "value", "The hex for the value"},
+                                    }},
+                                }},
                             }},
                         }},
                         {RPCResult::Type::STR_AMOUNT, "fee", /*optional=*/true, "The transaction fee paid if all UTXOs slots in the PSBT have been filled."},
@@ -1194,6 +1235,38 @@ static RPCHelpMan decodepsbt()
     TxToUniv(CTransaction(*psbtx.tx), uint256(), tx_univ, false);
     result.pushKV("tx", tx_univ);
 
+    // Add the global xpubs
+    UniValue global_xpubs(UniValue::VARR);
+    for (std::pair<KeyOriginInfo, std::set<CExtPubKey>> xpub_pair : psbtx.m_xpubs) {
+        for (auto& xpub : xpub_pair.second) {
+            std::vector<unsigned char> ser_xpub;
+            ser_xpub.assign(BIP32_EXTKEY_WITH_VERSION_SIZE, 0);
+            xpub.EncodeWithVersion(ser_xpub.data());
+
+            UniValue keypath(UniValue::VOBJ);
+            keypath.pushKV("xpub", EncodeBase58Check(ser_xpub));
+            keypath.pushKV("master_fingerprint", HexStr(Span<unsigned char>(xpub_pair.first.fingerprint, xpub_pair.first.fingerprint + 4)));
+            keypath.pushKV("path", WriteHDKeypath(xpub_pair.first.path));
+            global_xpubs.push_back(keypath);
+        }
+    }
+    result.pushKV("global_xpubs", global_xpubs);
+
+    // PSBT version
+    result.pushKV("psbt_version", static_cast<uint64_t>(psbtx.GetVersion()));
+
+    // Proprietary
+    UniValue proprietary(UniValue::VARR);
+    for (const auto& entry : psbtx.m_proprietary) {
+        UniValue this_prop(UniValue::VOBJ);
+        this_prop.pushKV("identifier", HexStr(entry.identifier));
+        this_prop.pushKV("subtype", entry.subtype);
+        this_prop.pushKV("key", HexStr(entry.key));
+        this_prop.pushKV("value", HexStr(entry.value));
+        proprietary.push_back(this_prop);
+    }
+    result.pushKV("proprietary", proprietary);
+
     // Unknown data
     UniValue unknowns(UniValue::VOBJ);
     for (auto entry : psbtx.unknown) {
@@ -1300,6 +1373,20 @@ static RPCHelpMan decodepsbt()
             in.pushKV("final_scriptwitness", txinwitness);
         }
 
+        // Proprietary
+        if (!input.m_proprietary.empty()) {
+            UniValue proprietary(UniValue::VARR);
+            for (const auto& entry : input.m_proprietary) {
+                UniValue this_prop(UniValue::VOBJ);
+                this_prop.pushKV("identifier", HexStr(entry.identifier));
+                this_prop.pushKV("subtype", entry.subtype);
+                this_prop.pushKV("key", HexStr(entry.key));
+                this_prop.pushKV("value", HexStr(entry.value));
+                proprietary.push_back(this_prop);
+            }
+            in.pushKV("proprietary", proprietary);
+        }
+
         // Unknown data
         if (input.unknown.size() > 0) {
             UniValue unknowns(UniValue::VOBJ);
@@ -1344,6 +1431,20 @@ static RPCHelpMan decodepsbt()
             out.pushKV("bip32_derivs", keypaths);
         }
 
+        // Proprietary
+        if (!output.m_proprietary.empty()) {
+            UniValue proprietary(UniValue::VARR);
+            for (const auto& entry : output.m_proprietary) {
+                UniValue this_prop(UniValue::VOBJ);
+                this_prop.pushKV("identifier", HexStr(entry.identifier));
+                this_prop.pushKV("subtype", entry.subtype);
+                this_prop.pushKV("key", HexStr(entry.key));
+                this_prop.pushKV("value", HexStr(entry.value));
+                proprietary.push_back(this_prop);
+            }
+            out.pushKV("proprietary", proprietary);
+        }
+
         // Unknown data
         if (output.unknown.size() > 0) {
             UniValue unknowns(UniValue::VOBJ);
@@ -1757,6 +1858,13 @@ static RPCHelpMan joinpsbts()
         for (unsigned int i = 0; i < psbt.tx->vout.size(); ++i) {
             merged_psbt.AddOutput(psbt.tx->vout[i], psbt.outputs[i]);
         }
+        for (auto& xpub_pair : psbt.m_xpubs) {
+            if (merged_psbt.m_xpubs.count(xpub_pair.first) == 0) {
+                merged_psbt.m_xpubs[xpub_pair.first] = xpub_pair.second;
+            } else {
+                merged_psbt.m_xpubs[xpub_pair.first].insert(xpub_pair.second.begin(), xpub_pair.second.end());
+            }
+        }
         merged_psbt.unknown.insert(psbt.unknown.begin(), psbt.unknown.end());
     }