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Diffstat (limited to 'src/script/script.h')
-rw-r--r-- | src/script/script.h | 645 |
1 files changed, 645 insertions, 0 deletions
diff --git a/src/script/script.h b/src/script/script.h new file mode 100644 index 0000000000..21847c09bd --- /dev/null +++ b/src/script/script.h @@ -0,0 +1,645 @@ +// Copyright (c) 2009-2010 Satoshi Nakamoto +// Copyright (c) 2009-2013 The Bitcoin developers +// Distributed under the MIT/X11 software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#ifndef H_BITCOIN_SCRIPT +#define H_BITCOIN_SCRIPT + +#include "key.h" +#include "tinyformat.h" +#include "utilstrencodings.h" + +#include <stdexcept> + +#include <boost/variant.hpp> + +static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes + +/** Script opcodes */ +enum opcodetype +{ + // push value + OP_0 = 0x00, + OP_FALSE = OP_0, + OP_PUSHDATA1 = 0x4c, + OP_PUSHDATA2 = 0x4d, + OP_PUSHDATA4 = 0x4e, + OP_1NEGATE = 0x4f, + OP_RESERVED = 0x50, + OP_1 = 0x51, + OP_TRUE=OP_1, + OP_2 = 0x52, + OP_3 = 0x53, + OP_4 = 0x54, + OP_5 = 0x55, + OP_6 = 0x56, + OP_7 = 0x57, + OP_8 = 0x58, + OP_9 = 0x59, + OP_10 = 0x5a, + OP_11 = 0x5b, + OP_12 = 0x5c, + OP_13 = 0x5d, + OP_14 = 0x5e, + OP_15 = 0x5f, + OP_16 = 0x60, + + // control + OP_NOP = 0x61, + OP_VER = 0x62, + OP_IF = 0x63, + OP_NOTIF = 0x64, + OP_VERIF = 0x65, + OP_VERNOTIF = 0x66, + OP_ELSE = 0x67, + OP_ENDIF = 0x68, + OP_VERIFY = 0x69, + OP_RETURN = 0x6a, + + // stack ops + OP_TOALTSTACK = 0x6b, + OP_FROMALTSTACK = 0x6c, + OP_2DROP = 0x6d, + OP_2DUP = 0x6e, + OP_3DUP = 0x6f, + OP_2OVER = 0x70, + OP_2ROT = 0x71, + OP_2SWAP = 0x72, + OP_IFDUP = 0x73, + OP_DEPTH = 0x74, + OP_DROP = 0x75, + OP_DUP = 0x76, + OP_NIP = 0x77, + OP_OVER = 0x78, + OP_PICK = 0x79, + OP_ROLL = 0x7a, + OP_ROT = 0x7b, + OP_SWAP = 0x7c, + OP_TUCK = 0x7d, + + // splice ops + OP_CAT = 0x7e, + OP_SUBSTR = 0x7f, + OP_LEFT = 0x80, + OP_RIGHT = 0x81, + OP_SIZE = 0x82, + + // bit logic + OP_INVERT = 0x83, + OP_AND = 0x84, + OP_OR = 0x85, + OP_XOR = 0x86, + OP_EQUAL = 0x87, + OP_EQUALVERIFY = 0x88, + OP_RESERVED1 = 0x89, + OP_RESERVED2 = 0x8a, + + // numeric + OP_1ADD = 0x8b, + OP_1SUB = 0x8c, + OP_2MUL = 0x8d, + OP_2DIV = 0x8e, + OP_NEGATE = 0x8f, + OP_ABS = 0x90, + OP_NOT = 0x91, + OP_0NOTEQUAL = 0x92, + + OP_ADD = 0x93, + OP_SUB = 0x94, + OP_MUL = 0x95, + OP_DIV = 0x96, + OP_MOD = 0x97, + OP_LSHIFT = 0x98, + OP_RSHIFT = 0x99, + + OP_BOOLAND = 0x9a, + OP_BOOLOR = 0x9b, + OP_NUMEQUAL = 0x9c, + OP_NUMEQUALVERIFY = 0x9d, + OP_NUMNOTEQUAL = 0x9e, + OP_LESSTHAN = 0x9f, + OP_GREATERTHAN = 0xa0, + OP_LESSTHANOREQUAL = 0xa1, + OP_GREATERTHANOREQUAL = 0xa2, + OP_MIN = 0xa3, + OP_MAX = 0xa4, + + OP_WITHIN = 0xa5, + + // crypto + OP_RIPEMD160 = 0xa6, + OP_SHA1 = 0xa7, + OP_SHA256 = 0xa8, + OP_HASH160 = 0xa9, + OP_HASH256 = 0xaa, + OP_CODESEPARATOR = 0xab, + OP_CHECKSIG = 0xac, + OP_CHECKSIGVERIFY = 0xad, + OP_CHECKMULTISIG = 0xae, + OP_CHECKMULTISIGVERIFY = 0xaf, + + // expansion + OP_NOP1 = 0xb0, + OP_NOP2 = 0xb1, + OP_NOP3 = 0xb2, + OP_NOP4 = 0xb3, + OP_NOP5 = 0xb4, + OP_NOP6 = 0xb5, + OP_NOP7 = 0xb6, + OP_NOP8 = 0xb7, + OP_NOP9 = 0xb8, + OP_NOP10 = 0xb9, + + + // template matching params + OP_SMALLDATA = 0xf9, + OP_SMALLINTEGER = 0xfa, + OP_PUBKEYS = 0xfb, + OP_PUBKEYHASH = 0xfd, + OP_PUBKEY = 0xfe, + + OP_INVALIDOPCODE = 0xff, +}; + +const char* GetOpName(opcodetype opcode); + +class scriptnum_error : public std::runtime_error +{ +public: + explicit scriptnum_error(const std::string& str) : std::runtime_error(str) {} +}; + +class CScriptNum +{ +// Numeric opcodes (OP_1ADD, etc) are restricted to operating on 4-byte integers. +// The semantics are subtle, though: operands must be in the range [-2^31 +1...2^31 -1], +// but results may overflow (and are valid as long as they are not used in a subsequent +// numeric operation). CScriptNum enforces those semantics by storing results as +// an int64 and allowing out-of-range values to be returned as a vector of bytes but +// throwing an exception if arithmetic is done or the result is interpreted as an integer. +public: + + explicit CScriptNum(const int64_t& n) + { + m_value = n; + } + + explicit CScriptNum(const std::vector<unsigned char>& vch) + { + if (vch.size() > nMaxNumSize) + throw scriptnum_error("CScriptNum(const std::vector<unsigned char>&) : overflow"); + m_value = set_vch(vch); + } + + inline bool operator==(const int64_t& rhs) const { return m_value == rhs; } + inline bool operator!=(const int64_t& rhs) const { return m_value != rhs; } + inline bool operator<=(const int64_t& rhs) const { return m_value <= rhs; } + inline bool operator< (const int64_t& rhs) const { return m_value < rhs; } + inline bool operator>=(const int64_t& rhs) const { return m_value >= rhs; } + inline bool operator> (const int64_t& rhs) const { return m_value > rhs; } + + inline bool operator==(const CScriptNum& rhs) const { return operator==(rhs.m_value); } + inline bool operator!=(const CScriptNum& rhs) const { return operator!=(rhs.m_value); } + inline bool operator<=(const CScriptNum& rhs) const { return operator<=(rhs.m_value); } + inline bool operator< (const CScriptNum& rhs) const { return operator< (rhs.m_value); } + inline bool operator>=(const CScriptNum& rhs) const { return operator>=(rhs.m_value); } + inline bool operator> (const CScriptNum& rhs) const { return operator> (rhs.m_value); } + + inline CScriptNum operator+( const int64_t& rhs) const { return CScriptNum(m_value + rhs);} + inline CScriptNum operator-( const int64_t& rhs) const { return CScriptNum(m_value - rhs);} + inline CScriptNum operator+( const CScriptNum& rhs) const { return operator+(rhs.m_value); } + inline CScriptNum operator-( const CScriptNum& rhs) const { return operator-(rhs.m_value); } + + inline CScriptNum& operator+=( const CScriptNum& rhs) { return operator+=(rhs.m_value); } + inline CScriptNum& operator-=( const CScriptNum& rhs) { return operator-=(rhs.m_value); } + + inline CScriptNum operator-() const + { + assert(m_value != std::numeric_limits<int64_t>::min()); + return CScriptNum(-m_value); + } + + inline CScriptNum& operator=( const int64_t& rhs) + { + m_value = rhs; + return *this; + } + + inline CScriptNum& operator+=( const int64_t& rhs) + { + assert(rhs == 0 || (rhs > 0 && m_value <= std::numeric_limits<int64_t>::max() - rhs) || + (rhs < 0 && m_value >= std::numeric_limits<int64_t>::min() - rhs)); + m_value += rhs; + return *this; + } + + inline CScriptNum& operator-=( const int64_t& rhs) + { + assert(rhs == 0 || (rhs > 0 && m_value >= std::numeric_limits<int64_t>::min() + rhs) || + (rhs < 0 && m_value <= std::numeric_limits<int64_t>::max() + rhs)); + m_value -= rhs; + return *this; + } + + int getint() const + { + if (m_value > std::numeric_limits<int>::max()) + return std::numeric_limits<int>::max(); + else if (m_value < std::numeric_limits<int>::min()) + return std::numeric_limits<int>::min(); + return m_value; + } + + std::vector<unsigned char> getvch() const + { + return serialize(m_value); + } + + static std::vector<unsigned char> serialize(const int64_t& value) + { + if(value == 0) + return std::vector<unsigned char>(); + + std::vector<unsigned char> result; + const bool neg = value < 0; + uint64_t absvalue = neg ? -value : value; + + while(absvalue) + { + result.push_back(absvalue & 0xff); + absvalue >>= 8; + } + +// - If the most significant byte is >= 0x80 and the value is positive, push a +// new zero-byte to make the significant byte < 0x80 again. + +// - If the most significant byte is >= 0x80 and the value is negative, push a +// new 0x80 byte that will be popped off when converting to an integral. + +// - If the most significant byte is < 0x80 and the value is negative, add +// 0x80 to it, since it will be subtracted and interpreted as a negative when +// converting to an integral. + + if (result.back() & 0x80) + result.push_back(neg ? 0x80 : 0); + else if (neg) + result.back() |= 0x80; + + return result; + } + + static const size_t nMaxNumSize = 4; + +private: + static int64_t set_vch(const std::vector<unsigned char>& vch) + { + if (vch.empty()) + return 0; + + int64_t result = 0; + for (size_t i = 0; i != vch.size(); ++i) + result |= static_cast<int64_t>(vch[i]) << 8*i; + + // If the input vector's most significant byte is 0x80, remove it from + // the result's msb and return a negative. + if (vch.back() & 0x80) + return -(result & ~(0x80ULL << (8 * (vch.size() - 1)))); + + return result; + } + + int64_t m_value; +}; + +inline std::string ValueString(const std::vector<unsigned char>& vch) +{ + if (vch.size() <= 4) + return strprintf("%d", CScriptNum(vch).getint()); + else + return HexStr(vch); +} + +class CNoDestination { +public: + friend bool operator==(const CNoDestination &a, const CNoDestination &b) { return true; } + friend bool operator<(const CNoDestination &a, const CNoDestination &b) { return true; } +}; + +/** A txout script template with a specific destination. It is either: + * * CNoDestination: no destination set + * * CKeyID: TX_PUBKEYHASH destination + * * CScriptID: TX_SCRIPTHASH destination + * A CTxDestination is the internal data type encoded in a CBitcoinAddress + */ +typedef boost::variant<CNoDestination, CKeyID, CScriptID> CTxDestination; + +/** Serialized script, used inside transaction inputs and outputs */ +class CScript : public std::vector<unsigned char> +{ +protected: + CScript& push_int64(int64_t n) + { + if (n == -1 || (n >= 1 && n <= 16)) + { + push_back(n + (OP_1 - 1)); + } + else + { + *this << CScriptNum::serialize(n); + } + return *this; + } +public: + CScript() { } + CScript(const CScript& b) : std::vector<unsigned char>(b.begin(), b.end()) { } + CScript(const_iterator pbegin, const_iterator pend) : std::vector<unsigned char>(pbegin, pend) { } +#ifndef _MSC_VER + CScript(const unsigned char* pbegin, const unsigned char* pend) : std::vector<unsigned char>(pbegin, pend) { } +#endif + + CScript& operator+=(const CScript& b) + { + insert(end(), b.begin(), b.end()); + return *this; + } + + friend CScript operator+(const CScript& a, const CScript& b) + { + CScript ret = a; + ret += b; + return ret; + } + + CScript(int64_t b) { operator<<(b); } + + explicit CScript(opcodetype b) { operator<<(b); } + explicit CScript(const uint256& b) { operator<<(b); } + explicit CScript(const CScriptNum& b) { operator<<(b); } + explicit CScript(const std::vector<unsigned char>& b) { operator<<(b); } + + + CScript& operator<<(int64_t b) { return push_int64(b); } + + CScript& operator<<(opcodetype opcode) + { + if (opcode < 0 || opcode > 0xff) + throw std::runtime_error("CScript::operator<<() : invalid opcode"); + insert(end(), (unsigned char)opcode); + return *this; + } + + CScript& operator<<(const uint160& b) + { + insert(end(), sizeof(b)); + insert(end(), (unsigned char*)&b, (unsigned char*)&b + sizeof(b)); + return *this; + } + + CScript& operator<<(const uint256& b) + { + insert(end(), sizeof(b)); + insert(end(), (unsigned char*)&b, (unsigned char*)&b + sizeof(b)); + return *this; + } + + CScript& operator<<(const CPubKey& key) + { + assert(key.size() < OP_PUSHDATA1); + insert(end(), (unsigned char)key.size()); + insert(end(), key.begin(), key.end()); + return *this; + } + + CScript& operator<<(const CScriptNum& b) + { + *this << b.getvch(); + return *this; + } + + CScript& operator<<(const std::vector<unsigned char>& b) + { + if (b.size() < OP_PUSHDATA1) + { + insert(end(), (unsigned char)b.size()); + } + else if (b.size() <= 0xff) + { + insert(end(), OP_PUSHDATA1); + insert(end(), (unsigned char)b.size()); + } + else if (b.size() <= 0xffff) + { + insert(end(), OP_PUSHDATA2); + unsigned short nSize = b.size(); + insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize)); + } + else + { + insert(end(), OP_PUSHDATA4); + unsigned int nSize = b.size(); + insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize)); + } + insert(end(), b.begin(), b.end()); + return *this; + } + + CScript& operator<<(const CScript& b) + { + // I'm not sure if this should push the script or concatenate scripts. + // If there's ever a use for pushing a script onto a script, delete this member fn + assert(!"Warning: Pushing a CScript onto a CScript with << is probably not intended, use + to concatenate!"); + return *this; + } + + + bool GetOp(iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>& vchRet) + { + // Wrapper so it can be called with either iterator or const_iterator + const_iterator pc2 = pc; + bool fRet = GetOp2(pc2, opcodeRet, &vchRet); + pc = begin() + (pc2 - begin()); + return fRet; + } + + bool GetOp(iterator& pc, opcodetype& opcodeRet) + { + const_iterator pc2 = pc; + bool fRet = GetOp2(pc2, opcodeRet, NULL); + pc = begin() + (pc2 - begin()); + return fRet; + } + + bool GetOp(const_iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>& vchRet) const + { + return GetOp2(pc, opcodeRet, &vchRet); + } + + bool GetOp(const_iterator& pc, opcodetype& opcodeRet) const + { + return GetOp2(pc, opcodeRet, NULL); + } + + bool GetOp2(const_iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>* pvchRet) const + { + opcodeRet = OP_INVALIDOPCODE; + if (pvchRet) + pvchRet->clear(); + if (pc >= end()) + return false; + + // Read instruction + if (end() - pc < 1) + return false; + unsigned int opcode = *pc++; + + // Immediate operand + if (opcode <= OP_PUSHDATA4) + { + unsigned int nSize = 0; + if (opcode < OP_PUSHDATA1) + { + nSize = opcode; + } + else if (opcode == OP_PUSHDATA1) + { + if (end() - pc < 1) + return false; + nSize = *pc++; + } + else if (opcode == OP_PUSHDATA2) + { + if (end() - pc < 2) + return false; + nSize = 0; + memcpy(&nSize, &pc[0], 2); + pc += 2; + } + else if (opcode == OP_PUSHDATA4) + { + if (end() - pc < 4) + return false; + memcpy(&nSize, &pc[0], 4); + pc += 4; + } + if (end() - pc < 0 || (unsigned int)(end() - pc) < nSize) + return false; + if (pvchRet) + pvchRet->assign(pc, pc + nSize); + pc += nSize; + } + + opcodeRet = (opcodetype)opcode; + return true; + } + + // Encode/decode small integers: + static int DecodeOP_N(opcodetype opcode) + { + if (opcode == OP_0) + return 0; + assert(opcode >= OP_1 && opcode <= OP_16); + return (int)opcode - (int)(OP_1 - 1); + } + static opcodetype EncodeOP_N(int n) + { + assert(n >= 0 && n <= 16); + if (n == 0) + return OP_0; + return (opcodetype)(OP_1+n-1); + } + + int FindAndDelete(const CScript& b) + { + int nFound = 0; + if (b.empty()) + return nFound; + iterator pc = begin(); + opcodetype opcode; + do + { + while (end() - pc >= (long)b.size() && memcmp(&pc[0], &b[0], b.size()) == 0) + { + erase(pc, pc + b.size()); + ++nFound; + } + } + while (GetOp(pc, opcode)); + return nFound; + } + int Find(opcodetype op) const + { + int nFound = 0; + opcodetype opcode; + for (const_iterator pc = begin(); pc != end() && GetOp(pc, opcode);) + if (opcode == op) + ++nFound; + return nFound; + } + + // Pre-version-0.6, Bitcoin always counted CHECKMULTISIGs + // as 20 sigops. With pay-to-script-hash, that changed: + // CHECKMULTISIGs serialized in scriptSigs are + // counted more accurately, assuming they are of the form + // ... OP_N CHECKMULTISIG ... + unsigned int GetSigOpCount(bool fAccurate) const; + + // Accurately count sigOps, including sigOps in + // pay-to-script-hash transactions: + unsigned int GetSigOpCount(const CScript& scriptSig) const; + + bool IsPayToScriptHash() const; + + // Called by IsStandardTx and P2SH VerifyScript (which makes it consensus-critical). + bool IsPushOnly() const; + + // Called by IsStandardTx. + bool HasCanonicalPushes() const; + + // Returns whether the script is guaranteed to fail at execution, + // regardless of the initial stack. This allows outputs to be pruned + // instantly when entering the UTXO set. + bool IsUnspendable() const + { + return (size() > 0 && *begin() == OP_RETURN); + } + + void SetDestination(const CTxDestination& address); + void SetMultisig(int nRequired, const std::vector<CPubKey>& keys); + + std::string ToString() const + { + std::string str; + opcodetype opcode; + std::vector<unsigned char> vch; + const_iterator pc = begin(); + while (pc < end()) + { + if (!str.empty()) + str += " "; + if (!GetOp(pc, opcode, vch)) + { + str += "[error]"; + return str; + } + if (0 <= opcode && opcode <= OP_PUSHDATA4) + str += ValueString(vch); + else + str += GetOpName(opcode); + } + return str; + } + + CScriptID GetID() const + { + return CScriptID(Hash160(*this)); + } + + void clear() + { + // The default std::vector::clear() does not release memory. + std::vector<unsigned char>().swap(*this); + } +}; + +#endif |