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Diffstat (limited to 'src/script/standard.cpp')
| -rw-r--r-- | src/script/standard.cpp | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/src/script/standard.cpp b/src/script/standard.cpp new file mode 100644 index 000000000..bb178f49f --- /dev/null +++ b/src/script/standard.cpp @@ -0,0 +1,325 @@ +// Copyright (c) 2009-2010 Satoshi Nakamoto +// Copyright (c) 2009-2015 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include "script/standard.h" + +#include "pubkey.h" +#include "script/script.h" +#include "util.h" +#include "utilstrencodings.h" + +#include <boost/foreach.hpp> + +using namespace std; + +typedef vector<unsigned char> valtype; + +bool fAcceptDatacarrier = DEFAULT_ACCEPT_DATACARRIER; +unsigned nMaxDatacarrierBytes = MAX_OP_RETURN_RELAY; + +CScriptID::CScriptID(const CScript& in) : uint160(Hash160(in.begin(), in.end())) {} + +const char* GetTxnOutputType(txnouttype t) +{ + switch (t) + { + case TX_NONSTANDARD: return "nonstandard"; + case TX_PUBKEY: return "pubkey"; + case TX_PUBKEYHASH: return "pubkeyhash"; + 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; +} + +/** + * Return public keys or hashes from scriptPubKey, for 'standard' transaction types. + */ +bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsigned char> >& vSolutionsRet) +{ + // Templates + static multimap<txnouttype, CScript> mTemplates; + if (mTemplates.empty()) + { + // Standard tx, sender provides pubkey, receiver adds signature + mTemplates.insert(make_pair(TX_PUBKEY, CScript() << OP_PUBKEY << OP_CHECKSIG)); + + // Bitcoin address tx, sender provides hash of pubkey, receiver provides signature and pubkey + mTemplates.insert(make_pair(TX_PUBKEYHASH, CScript() << OP_DUP << OP_HASH160 << OP_PUBKEYHASH << OP_EQUALVERIFY << OP_CHECKSIG)); + + // Sender provides N pubkeys, receivers provides M signatures + mTemplates.insert(make_pair(TX_MULTISIG, CScript() << OP_SMALLINTEGER << OP_PUBKEYS << OP_SMALLINTEGER << OP_CHECKMULTISIG)); + } + + vSolutionsRet.clear(); + + // Shortcut for pay-to-script-hash, which are more constrained than the other types: + // it is always OP_HASH160 20 [20 byte hash] OP_EQUAL + if (scriptPubKey.IsPayToScriptHash()) + { + typeRet = TX_SCRIPTHASH; + vector<unsigned char> hashBytes(scriptPubKey.begin()+2, scriptPubKey.begin()+22); + vSolutionsRet.push_back(hashBytes); + 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 + // byte passes the IsPushOnly() test we don't care what exactly is in the + // script. + if (scriptPubKey.size() >= 1 && scriptPubKey[0] == OP_RETURN && scriptPubKey.IsPushOnly(scriptPubKey.begin()+1)) { + typeRet = TX_NULL_DATA; + return true; + } + + // Scan templates + const CScript& script1 = scriptPubKey; + BOOST_FOREACH(const PAIRTYPE(txnouttype, CScript)& tplate, mTemplates) + { + const CScript& script2 = tplate.second; + vSolutionsRet.clear(); + + opcodetype opcode1, opcode2; + vector<unsigned char> vch1, vch2; + + // Compare + CScript::const_iterator pc1 = script1.begin(); + CScript::const_iterator pc2 = script2.begin(); + while (true) + { + if (pc1 == script1.end() && pc2 == script2.end()) + { + // Found a match + typeRet = tplate.first; + if (typeRet == TX_MULTISIG) + { + // Additional checks for TX_MULTISIG: + unsigned char m = vSolutionsRet.front()[0]; + unsigned char n = vSolutionsRet.back()[0]; + if (m < 1 || n < 1 || m > n || vSolutionsRet.size()-2 != n) + return false; + } + return true; + } + if (!script1.GetOp(pc1, opcode1, vch1)) + break; + if (!script2.GetOp(pc2, opcode2, vch2)) + break; + + // Template matching opcodes: + if (opcode2 == OP_PUBKEYS) + { + while (vch1.size() >= 33 && vch1.size() <= 65) + { + vSolutionsRet.push_back(vch1); + if (!script1.GetOp(pc1, opcode1, vch1)) + break; + } + if (!script2.GetOp(pc2, opcode2, vch2)) + break; + // Normal situation is to fall through + // to other if/else statements + } + + if (opcode2 == OP_PUBKEY) + { + if (vch1.size() < 33 || vch1.size() > 65) + break; + vSolutionsRet.push_back(vch1); + } + else if (opcode2 == OP_PUBKEYHASH) + { + if (vch1.size() != sizeof(uint160)) + break; + vSolutionsRet.push_back(vch1); + } + else if (opcode2 == OP_SMALLINTEGER) + { // Single-byte small integer pushed onto vSolutions + if (opcode1 == OP_0 || + (opcode1 >= OP_1 && opcode1 <= OP_16)) + { + char n = (char)CScript::DecodeOP_N(opcode1); + vSolutionsRet.push_back(valtype(1, n)); + } + else + break; + } + else if (opcode1 != opcode2 || vch1 != vch2) + { + // Others must match exactly + break; + } + } + } + + vSolutionsRet.clear(); + typeRet = TX_NONSTANDARD; + return false; +} + +bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) +{ + vector<valtype> vSolutions; + txnouttype whichType; + if (!Solver(scriptPubKey, whichType, vSolutions)) + return false; + + if (whichType == TX_PUBKEY) + { + CPubKey pubKey(vSolutions[0]); + if (!pubKey.IsValid()) + return false; + + addressRet = pubKey.GetID(); + return true; + } + else if (whichType == TX_PUBKEYHASH) + { + addressRet = CKeyID(uint160(vSolutions[0])); + return true; + } + else if (whichType == TX_SCRIPTHASH) + { + addressRet = CScriptID(uint160(vSolutions[0])); + return true; + } + // Multisig txns have more than one address... + return false; +} + +bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, vector<CTxDestination>& addressRet, int& nRequiredRet) +{ + addressRet.clear(); + typeRet = TX_NONSTANDARD; + vector<valtype> vSolutions; + if (!Solver(scriptPubKey, typeRet, vSolutions)) + return false; + if (typeRet == TX_NULL_DATA){ + // This is data, not addresses + return false; + } + + if (typeRet == TX_MULTISIG) + { + nRequiredRet = vSolutions.front()[0]; + for (unsigned int i = 1; i < vSolutions.size()-1; i++) + { + CPubKey pubKey(vSolutions[i]); + if (!pubKey.IsValid()) + continue; + + CTxDestination address = pubKey.GetID(); + addressRet.push_back(address); + } + + if (addressRet.empty()) + return false; + } + else + { + nRequiredRet = 1; + CTxDestination address; + if (!ExtractDestination(scriptPubKey, address)) + return false; + addressRet.push_back(address); + } + + return true; +} + +namespace +{ +class CScriptVisitor : public boost::static_visitor<bool> +{ +private: + CScript *script; +public: + CScriptVisitor(CScript *scriptin) { script = scriptin; } + + bool operator()(const CNoDestination &dest) const { + script->clear(); + return false; + } + + bool operator()(const CKeyID &keyID) const { + script->clear(); + *script << OP_DUP << OP_HASH160 << ToByteVector(keyID) << OP_EQUALVERIFY << OP_CHECKSIG; + return true; + } + + bool operator()(const CScriptID &scriptID) const { + script->clear(); + *script << OP_HASH160 << ToByteVector(scriptID) << OP_EQUAL; + return true; + } +}; +} + +CScript GetScriptForDestination(const CTxDestination& dest) +{ + CScript script; + + boost::apply_visitor(CScriptVisitor(&script), dest); + return script; +} + +CScript GetScriptForRawPubKey(const CPubKey& pubKey) +{ + return CScript() << std::vector<unsigned char>(pubKey.begin(), pubKey.end()) << OP_CHECKSIG; +} + +CScript GetScriptForMultisig(int nRequired, const std::vector<CPubKey>& keys) +{ + CScript script; + + script << CScript::EncodeOP_N(nRequired); + BOOST_FOREACH(const CPubKey& key, keys) + script << ToByteVector(key); + 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; +} |