Merge #8149: Segregated witness rebased

f852813 BIP9 parameters for testnet (Johnson Lau)
070dbc4 --- [SEGWIT] begin: deployment --- (Pieter Wuille)
fdb43df [qa] Add GetTransactionSigOpCost unit tests (Jonas Nick)
d846e02 [qa] script_tests: witness tests can specify tx amount (Suhas Daftuar)
330b0f3 [qa] p2p segwit tests (Suhas Daftuar)
4f7ff00 [qa] Add rpc test for segwit (Alex Morcos)
66cca79 [qa] Autogeneration support for witness in script_tests (Pieter Wuille)
06d3805 [qa] Add segwit support to script_tests (Pieter Wuille)
00f46cb [qa] Add transaction tests for segwit (NicolasDorier)
0aa9207 [qa] Witness version 0 signing unit tests (Pieter Wuille)
978e200 --- [SEGWIT] begin: tests --- (Pieter Wuille)
745eb67 [RPC] signrawtransaction can sign P2WSH (NicolasDorier)
f4691ab [RPC] Add wallet support for witness transactions (using P2SH) (Pieter Wuille)
605e847 BIP143: Signing logic (Pieter Wuille)
9757b57 --- [SEGWIT] begin: wallet --- (Pieter Wuille)
af87a67 Do not use compact blocks when segwit is enabled (Pieter Wuille)
6032f69 Add rewind logic to deal with post-fork software updates (Pieter Wuille)
b7dbeb2 [libconsensus] Script verification API with amounts (Thomas Kerin)
2b1f6f9 BIP141: Other consensus critical limits, and BIP145 (Pieter Wuille)
7c4bf77 [RPC] Return witness data in blockchain RPCs (Johnson Lau)
3dd4102 BIP143: Verification logic (Pieter Wuille)
0ef1dd3 Refactor script validation to observe amounts (Pieter Wuille)
b8a9749 BIP144: Handshake and relay (receiver side) (Pieter Wuille)
8b49040 BIP141: Commitment structure and deployment (Pieter Wuille)
449f9b8 BIP141: Witness program (Pieter Wuille)
7030d9e BIP144: Serialization, hashes, relay (sender side) (Pieter Wuille)
ecacfd9 --- [SEGWIT] begin: P2P/node/consensus --- (Pieter Wuille)

1 files changed, 41 insertions, 0 deletions

diff --git a/src/script/standard.cpp b/src/script/standard.cpp
index 67b6af327..bb178f49f 100644
--- a/src/script/standard.cpp
+++ b/src/script/standard.cpp
@@ -31,6 +31,8 @@ const char* GetTxnOutputType(txnouttype t)
     case TX_SCRIPTHASH: return "scripthash";
     case TX_MULTISIG: return "multisig";
     case TX_NULL_DATA: return "nulldata";
+    case TX_WITNESS_V0_KEYHASH: return "witness_v0_keyhash";
+    case TX_WITNESS_V0_SCRIPTHASH: return "witness_v0_scripthash";
     }
     return NULL;
 }
@@ -66,6 +68,22 @@ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsi
         return true;
     }
 
+    int witnessversion;
+    std::vector<unsigned char> witnessprogram;
+    if (scriptPubKey.IsWitnessProgram(witnessversion, witnessprogram)) {
+        if (witnessversion == 0 && witnessprogram.size() == 20) {
+            typeRet = TX_WITNESS_V0_KEYHASH;
+            vSolutionsRet.push_back(witnessprogram);
+            return true;
+        }
+        if (witnessversion == 0 && witnessprogram.size() == 32) {
+            typeRet = TX_WITNESS_V0_SCRIPTHASH;
+            vSolutionsRet.push_back(witnessprogram);
+            return true;
+        }
+        return false;
+    }
+
     // Provably prunable, data-carrying output
     //
     // So long as script passes the IsUnspendable() test and all but the first
@@ -282,3 +300,26 @@ CScript GetScriptForMultisig(int nRequired, const std::vector<CPubKey>& keys)
     script << CScript::EncodeOP_N(keys.size()) << OP_CHECKMULTISIG;
     return script;
 }
+
+CScript GetScriptForWitness(const CScript& redeemscript)
+{
+    CScript ret;
+
+    txnouttype typ;
+    std::vector<std::vector<unsigned char> > vSolutions;
+    if (Solver(redeemscript, typ, vSolutions)) {
+        if (typ == TX_PUBKEY) {
+            unsigned char h160[20];
+            CHash160().Write(&vSolutions[0][0], vSolutions[0].size()).Finalize(h160);
+            ret << OP_0 << std::vector<unsigned char>(&h160[0], &h160[20]);
+            return ret;
+        } else if (typ == TX_PUBKEYHASH) {
+           ret << OP_0 << vSolutions[0];
+           return ret;
+        }
+    }
+    uint256 hash;
+    CSHA256().Write(&redeemscript[0], redeemscript.size()).Finalize(hash.begin());
+    ret << OP_0 << ToByteVector(hash);
+    return ret;
+}