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, 38 insertions, 0 deletions

diff --git a/src/script/script.cpp b/src/script/script.cpp
index 9f2809e593..da551c23ee 100644
--- a/src/script/script.cpp
+++ b/src/script/script.cpp
@@ -210,6 +210,32 @@ 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
+{
+    if (this->size() < 4 || this->size() > 42) {
+        return false;
+    }
+    if ((*this)[0] != OP_0 && ((*this)[0] < OP_1 || (*this)[0] > OP_16)) {
+        return false;
+    }
+    if ((size_t)((*this)[1] + 2) == this->size()) {
+        version = DecodeOP_N((opcodetype)(*this)[0]);
+        program = std::vector<unsigned char>(this->begin() + 2, this->end());
+        return true;
+    }
+    return false;
+}
+
 bool CScript::IsPushOnly(const_iterator pc) const
 {
     while (pc < end())
@@ -231,3 +257,15 @@ bool CScript::IsPushOnly() const
 {
     return this->IsPushOnly(begin());
 }
+
+std::string CScriptWitness::ToString() const
+{
+    std::string ret = "CScriptWitness(";
+    for (unsigned int i = 0; i < stack.size(); i++) {
+        if (i) {
+            ret += ", ";
+        }
+        ret += HexStr(stack[i]);
+    }
+    return ret + ")";
+}