From 745eb678ef5d52c74edcd9c322ebd1f3232a9310 Mon Sep 17 00:00:00 2001
From: NicolasDorier <nicolas.dorier@gmail.com>
Date: Sun, 10 Apr 2016 15:59:23 +0900
Subject: [PATCH] [RPC] signrawtransaction can sign P2WSH

---
 src/bitcoin-tx.cpp         | 2 +-
 src/rpc/rawtransaction.cpp | 4 ++--
 src/script/script.cpp      | 8 ++++++++
 src/script/script.h        | 1 +
 4 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/bitcoin-tx.cpp b/src/bitcoin-tx.cpp
index f457ea2bc..8e8ac4745 100644
--- a/src/bitcoin-tx.cpp
+++ b/src/bitcoin-tx.cpp
@@ -454,7 +454,7 @@ static void MutateTxSign(CMutableTransaction& tx, const string& flagStr)
 
             // if redeemScript given and private keys given,
             // add redeemScript to the tempKeystore so it can be signed:
-            if (fGivenKeys && scriptPubKey.IsPayToScriptHash() &&
+            if (fGivenKeys && (scriptPubKey.IsPayToScriptHash() || scriptPubKey.IsPayToWitnessScriptHash()) &&
                 prevOut.exists("redeemScript")) {
                 UniValue v = prevOut["redeemScript"];
                 vector<unsigned char> rsData(ParseHexUV(v, "redeemScript"));
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 56ba805b1..3270cd384 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -592,7 +592,7 @@ UniValue signrawtransaction(const UniValue& params, bool fHelp)
             "         \"txid\":\"id\",             (string, required) The transaction id\n"
             "         \"vout\":n,                  (numeric, required) The output number\n"
             "         \"scriptPubKey\": \"hex\",   (string, required) script key\n"
-            "         \"redeemScript\": \"hex\",   (string, required for P2SH) redeem script\n"
+            "         \"redeemScript\": \"hex\",   (string, required for P2SH or P2WSH) redeem script\n"
             "         \"amount\": value            (numeric, required) The amount spent\n"
             "       }\n"
             "       ,...\n"
@@ -744,7 +744,7 @@ UniValue signrawtransaction(const UniValue& params, bool fHelp)
 
             // if redeemScript given and not using the local wallet (private keys
             // given), add redeemScript to the tempKeystore so it can be signed:
-            if (fGivenKeys && scriptPubKey.IsPayToScriptHash()) {
+            if (fGivenKeys && (scriptPubKey.IsPayToScriptHash() || scriptPubKey.IsPayToWitnessScriptHash())) {
                 RPCTypeCheckObj(prevOut,
                     {
                         {"txid", UniValueType(UniValue::VSTR)},
diff --git a/src/script/script.cpp b/src/script/script.cpp
index 73f5a61bf..da551c23e 100644
--- a/src/script/script.cpp
+++ b/src/script/script.cpp
@@ -210,6 +210,14 @@ bool CScript::IsPayToScriptHash() const
             (*this)[22] == OP_EQUAL);
 }
 
+bool CScript::IsPayToWitnessScriptHash() const
+{
+    // Extra-fast test for pay-to-witness-script-hash CScripts:
+    return (this->size() == 34 &&
+            (*this)[0] == OP_0 &&
+            (*this)[1] == 0x20);
+}
+
 // A witness program is any valid CScript that consists of a 1-byte push opcode
 // followed by a data push between 2 and 40 bytes.
 bool CScript::IsWitnessProgram(int& version, std::vector<unsigned char>& program) const
diff --git a/src/script/script.h b/src/script/script.h
index b9b5be901..71af3754b 100644
--- a/src/script/script.h
+++ b/src/script/script.h
@@ -621,6 +621,7 @@ public:
     unsigned int GetSigOpCount(const CScript& scriptSig) const;
 
     bool IsPayToScriptHash() const;
+    bool IsPayToWitnessScriptHash() const;
     bool IsWitnessProgram(int& version, std::vector<unsigned char>& program) const;
 
     /** Called by IsStandardTx and P2SH/BIP62 VerifyScript (which makes it consensus-critical). */