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+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2014 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_SCRIPT_SCRIPT_H
+#define BITCOIN_SCRIPT_SCRIPT_H
+
+#include "crypto/common.h"
+#include "prevector.h"
+
+#include <assert.h>
+#include <climits>
+#include <limits>
+#include <stdexcept>
+#include <stdint.h>
+#include <string.h>
+#include <string>
+#include <vector>
+
+// Maximum number of bytes pushable to the stack
+static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520;
+
+// Maximum number of non-push operations per script
+static const int MAX_OPS_PER_SCRIPT = 201;
+
+// Maximum number of public keys per multisig
+static const int MAX_PUBKEYS_PER_MULTISIG = 20;
+
+// Threshold for nLockTime: below this value it is interpreted as block number,
+// otherwise as UNIX timestamp.
+static const unsigned int LOCKTIME_THRESHOLD = 500000000; // Tue Nov 5 00:53:20 1985 UTC
+
+template <typename T>
+std::vector<unsigned char> ToByteVector(const T& in)
+{
+ return std::vector<unsigned char>(in.begin(), in.end());
+}
+
+/** 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_CHECKLOCKTIMEVERIFY = 0xb1,
+ OP_NOP2 = OP_CHECKLOCKTIMEVERIFY,
+ 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_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;
+ }
+
+ static const size_t nDefaultMaxNumSize = 4;
+
+ explicit CScriptNum(const std::vector<unsigned char>& vch, bool fRequireMinimal,
+ const size_t nMaxNumSize = nDefaultMaxNumSize)
+ {
+ if (vch.size() > nMaxNumSize) {
+ throw scriptnum_error("script number overflow");
+ }
+ if (fRequireMinimal && vch.size() > 0) {
+ // Check that the number is encoded with the minimum possible
+ // number of bytes.
+ //
+ // If the most-significant-byte - excluding the sign bit - is zero
+ // then we're not minimal. Note how this test also rejects the
+ // negative-zero encoding, 0x80.
+ if ((vch.back() & 0x7f) == 0) {
+ // One exception: if there's more than one byte and the most
+ // significant bit of the second-most-significant-byte is set
+ // it would conflict with the sign bit. An example of this case
+ // is +-255, which encode to 0xff00 and 0xff80 respectively.
+ // (big-endian).
+ if (vch.size() <= 1 || (vch[vch.size() - 2] & 0x80) == 0) {
+ throw scriptnum_error("non-minimally encoded script number");
+ }
+ }
+ }
+ 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;
+ }
+
+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 -((int64_t)(result & ~(0x80ULL << (8 * (vch.size() - 1)))));
+
+ return result;
+ }
+
+ int64_t m_value;
+};
+
+typedef prevector<28, unsigned char> CScriptBase;
+
+/** Serialized script, used inside transaction inputs and outputs */
+class CScript : public CScriptBase
+{
+protected:
+ CScript& push_int64(int64_t n)
+ {
+ if (n == -1 || (n >= 1 && n <= 16))
+ {
+ push_back(n + (OP_1 - 1));
+ }
+ else if (n == 0)
+ {
+ push_back(OP_0);
+ }
+ else
+ {
+ *this << CScriptNum::serialize(n);
+ }
+ return *this;
+ }
+public:
+ CScript() { }
+ CScript(const CScript& b) : CScriptBase(b.begin(), b.end()) { }
+ CScript(const_iterator pbegin, const_iterator pend) : CScriptBase(pbegin, pend) { }
+ CScript(std::vector<unsigned char>::const_iterator pbegin, std::vector<unsigned char>::const_iterator pend) : CScriptBase(pbegin, pend) { }
+ CScript(const unsigned char* pbegin, const unsigned char* pend) : CScriptBase(pbegin, pend) { }
+
+ 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 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 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);
+ uint8_t data[2];
+ WriteLE16(data, b.size());
+ insert(end(), data, data + sizeof(data));
+ }
+ else
+ {
+ insert(end(), OP_PUSHDATA4);
+ uint8_t data[4];
+ WriteLE32(data, b.size());
+ insert(end(), data, data + sizeof(data));
+ }
+ 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 = ReadLE16(&pc[0]);
+ pc += 2;
+ }
+ else if (opcode == OP_PUSHDATA4)
+ {
+ if (end() - pc < 4)
+ return false;
+ nSize = ReadLE32(&pc[0]);
+ 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)
+ {
+ pc = 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/BIP62 VerifyScript (which makes it consensus-critical). */
+ bool IsPushOnly(const_iterator pc) const;
+ bool IsPushOnly() 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 clear()
+ {
+ // The default std::vector::clear() does not release memory.
+ CScriptBase().swap(*this);
+ }
+};
+
+class CReserveScript
+{
+public:
+ CScript reserveScript;
+ virtual void KeepScript() {}
+ CReserveScript() {}
+ virtual ~CReserveScript() {}
+};
+
+#endif // BITCOIN_SCRIPT_SCRIPT_H
generated by cgit v1.2.3 (git 2.26.2) at 2025-03-23 15:32:22 +0000