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|
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2011 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "headers.h"
using namespace std;
using namespace boost;
bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType);
typedef vector<unsigned char> valtype;
static const valtype vchFalse(0);
static const valtype vchZero(0);
static const valtype vchTrue(1, 1);
static const CBigNum bnZero(0);
static const CBigNum bnOne(1);
static const CBigNum bnFalse(0);
static const CBigNum bnTrue(1);
static const size_t nMaxNumSize = 4;
CBigNum CastToBigNum(const valtype& vch)
{
if (vch.size() > nMaxNumSize)
throw runtime_error("CastToBigNum() : overflow");
// Get rid of extra leading zeros
return CBigNum(CBigNum(vch).getvch());
}
bool CastToBool(const valtype& vch)
{
for (int i = 0; i < vch.size(); i++)
{
if (vch[i] != 0)
{
// Can be negative zero
if (i == vch.size()-1 && vch[i] == 0x80)
return false;
return true;
}
}
return false;
}
void MakeSameSize(valtype& vch1, valtype& vch2)
{
// Lengthen the shorter one
if (vch1.size() < vch2.size())
vch1.resize(vch2.size(), 0);
if (vch2.size() < vch1.size())
vch2.resize(vch1.size(), 0);
}
//
// Script is a stack machine (like Forth) that evaluates a predicate
// returning a bool indicating valid or not. There are no loops.
//
#define stacktop(i) (stack.at(stack.size()+(i)))
#define altstacktop(i) (altstack.at(altstack.size()+(i)))
static inline void popstack(vector<valtype>& stack)
{
if (stack.empty())
throw runtime_error("popstack() : stack empty");
stack.pop_back();
}
bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType)
{
CAutoBN_CTX pctx;
CScript::const_iterator pc = script.begin();
CScript::const_iterator pend = script.end();
CScript::const_iterator pbegincodehash = script.begin();
opcodetype opcode;
valtype vchPushValue;
vector<bool> vfExec;
vector<valtype> altstack;
if (script.size() > 10000)
return false;
int nOpCount = 0;
try
{
while (pc < pend)
{
bool fExec = !count(vfExec.begin(), vfExec.end(), false);
//
// Read instruction
//
if (!script.GetOp(pc, opcode, vchPushValue))
return false;
if (vchPushValue.size() > 520)
return false;
if (opcode > OP_16 && ++nOpCount > 201)
return false;
if (opcode == OP_CAT ||
opcode == OP_SUBSTR ||
opcode == OP_LEFT ||
opcode == OP_RIGHT ||
opcode == OP_INVERT ||
opcode == OP_AND ||
opcode == OP_OR ||
opcode == OP_XOR ||
opcode == OP_2MUL ||
opcode == OP_2DIV ||
opcode == OP_MUL ||
opcode == OP_DIV ||
opcode == OP_MOD ||
opcode == OP_LSHIFT ||
opcode == OP_RSHIFT)
return false;
if (fExec && 0 <= opcode && opcode <= OP_PUSHDATA4)
stack.push_back(vchPushValue);
else if (fExec || (OP_IF <= opcode && opcode <= OP_ENDIF))
switch (opcode)
{
//
// Push value
//
case OP_1NEGATE:
case OP_1:
case OP_2:
case OP_3:
case OP_4:
case OP_5:
case OP_6:
case OP_7:
case OP_8:
case OP_9:
case OP_10:
case OP_11:
case OP_12:
case OP_13:
case OP_14:
case OP_15:
case OP_16:
{
// ( -- value)
CBigNum bn((int)opcode - (int)(OP_1 - 1));
stack.push_back(bn.getvch());
}
break;
//
// Control
//
case OP_NOP:
case OP_NOP1: case OP_NOP2: case OP_NOP3: case OP_NOP4: case OP_NOP5:
case OP_NOP6: case OP_NOP7: case OP_NOP8: case OP_NOP9: case OP_NOP10:
break;
case OP_IF:
case OP_NOTIF:
{
// <expression> if [statements] [else [statements]] endif
bool fValue = false;
if (fExec)
{
if (stack.size() < 1)
return false;
valtype& vch = stacktop(-1);
fValue = CastToBool(vch);
if (opcode == OP_NOTIF)
fValue = !fValue;
popstack(stack);
}
vfExec.push_back(fValue);
}
break;
case OP_ELSE:
{
if (vfExec.empty())
return false;
vfExec.back() = !vfExec.back();
}
break;
case OP_ENDIF:
{
if (vfExec.empty())
return false;
vfExec.pop_back();
}
break;
case OP_VERIFY:
{
// (true -- ) or
// (false -- false) and return
if (stack.size() < 1)
return false;
bool fValue = CastToBool(stacktop(-1));
if (fValue)
popstack(stack);
else
return false;
}
break;
case OP_RETURN:
{
return false;
}
break;
//
// Stack ops
//
case OP_TOALTSTACK:
{
if (stack.size() < 1)
return false;
altstack.push_back(stacktop(-1));
popstack(stack);
}
break;
case OP_FROMALTSTACK:
{
if (altstack.size() < 1)
return false;
stack.push_back(altstacktop(-1));
popstack(altstack);
}
break;
case OP_2DROP:
{
// (x1 x2 -- )
if (stack.size() < 2)
return false;
popstack(stack);
popstack(stack);
}
break;
case OP_2DUP:
{
// (x1 x2 -- x1 x2 x1 x2)
if (stack.size() < 2)
return false;
valtype vch1 = stacktop(-2);
valtype vch2 = stacktop(-1);
stack.push_back(vch1);
stack.push_back(vch2);
}
break;
case OP_3DUP:
{
// (x1 x2 x3 -- x1 x2 x3 x1 x2 x3)
if (stack.size() < 3)
return false;
valtype vch1 = stacktop(-3);
valtype vch2 = stacktop(-2);
valtype vch3 = stacktop(-1);
stack.push_back(vch1);
stack.push_back(vch2);
stack.push_back(vch3);
}
break;
case OP_2OVER:
{
// (x1 x2 x3 x4 -- x1 x2 x3 x4 x1 x2)
if (stack.size() < 4)
return false;
valtype vch1 = stacktop(-4);
valtype vch2 = stacktop(-3);
stack.push_back(vch1);
stack.push_back(vch2);
}
break;
case OP_2ROT:
{
// (x1 x2 x3 x4 x5 x6 -- x3 x4 x5 x6 x1 x2)
if (stack.size() < 6)
return false;
valtype vch1 = stacktop(-6);
valtype vch2 = stacktop(-5);
stack.erase(stack.end()-6, stack.end()-4);
stack.push_back(vch1);
stack.push_back(vch2);
}
break;
case OP_2SWAP:
{
// (x1 x2 x3 x4 -- x3 x4 x1 x2)
if (stack.size() < 4)
return false;
swap(stacktop(-4), stacktop(-2));
swap(stacktop(-3), stacktop(-1));
}
break;
case OP_IFDUP:
{
// (x - 0 | x x)
if (stack.size() < 1)
return false;
valtype vch = stacktop(-1);
if (CastToBool(vch))
stack.push_back(vch);
}
break;
case OP_DEPTH:
{
// -- stacksize
CBigNum bn(stack.size());
stack.push_back(bn.getvch());
}
break;
case OP_DROP:
{
// (x -- )
if (stack.size() < 1)
return false;
popstack(stack);
}
break;
case OP_DUP:
{
// (x -- x x)
if (stack.size() < 1)
return false;
valtype vch = stacktop(-1);
stack.push_back(vch);
}
break;
case OP_NIP:
{
// (x1 x2 -- x2)
if (stack.size() < 2)
return false;
stack.erase(stack.end() - 2);
}
break;
case OP_OVER:
{
// (x1 x2 -- x1 x2 x1)
if (stack.size() < 2)
return false;
valtype vch = stacktop(-2);
stack.push_back(vch);
}
break;
case OP_PICK:
case OP_ROLL:
{
// (xn ... x2 x1 x0 n - xn ... x2 x1 x0 xn)
// (xn ... x2 x1 x0 n - ... x2 x1 x0 xn)
if (stack.size() < 2)
return false;
int n = CastToBigNum(stacktop(-1)).getint();
popstack(stack);
if (n < 0 || n >= stack.size())
return false;
valtype vch = stacktop(-n-1);
if (opcode == OP_ROLL)
stack.erase(stack.end()-n-1);
stack.push_back(vch);
}
break;
case OP_ROT:
{
// (x1 x2 x3 -- x2 x3 x1)
// x2 x1 x3 after first swap
// x2 x3 x1 after second swap
if (stack.size() < 3)
return false;
swap(stacktop(-3), stacktop(-2));
swap(stacktop(-2), stacktop(-1));
}
break;
case OP_SWAP:
{
// (x1 x2 -- x2 x1)
if (stack.size() < 2)
return false;
swap(stacktop(-2), stacktop(-1));
}
break;
case OP_TUCK:
{
// (x1 x2 -- x2 x1 x2)
if (stack.size() < 2)
return false;
valtype vch = stacktop(-1);
stack.insert(stack.end()-2, vch);
}
break;
//
// Splice ops
//
case OP_CAT:
{
// (x1 x2 -- out)
if (stack.size() < 2)
return false;
valtype& vch1 = stacktop(-2);
valtype& vch2 = stacktop(-1);
vch1.insert(vch1.end(), vch2.begin(), vch2.end());
popstack(stack);
if (stacktop(-1).size() > 520)
return false;
}
break;
case OP_SUBSTR:
{
// (in begin size -- out)
if (stack.size() < 3)
return false;
valtype& vch = stacktop(-3);
int nBegin = CastToBigNum(stacktop(-2)).getint();
int nEnd = nBegin + CastToBigNum(stacktop(-1)).getint();
if (nBegin < 0 || nEnd < nBegin)
return false;
if (nBegin > vch.size())
nBegin = vch.size();
if (nEnd > vch.size())
nEnd = vch.size();
vch.erase(vch.begin() + nEnd, vch.end());
vch.erase(vch.begin(), vch.begin() + nBegin);
popstack(stack);
popstack(stack);
}
break;
case OP_LEFT:
case OP_RIGHT:
{
// (in size -- out)
if (stack.size() < 2)
return false;
valtype& vch = stacktop(-2);
int nSize = CastToBigNum(stacktop(-1)).getint();
if (nSize < 0)
return false;
if (nSize > vch.size())
nSize = vch.size();
if (opcode == OP_LEFT)
vch.erase(vch.begin() + nSize, vch.end());
else
vch.erase(vch.begin(), vch.end() - nSize);
popstack(stack);
}
break;
case OP_SIZE:
{
// (in -- in size)
if (stack.size() < 1)
return false;
CBigNum bn(stacktop(-1).size());
stack.push_back(bn.getvch());
}
break;
//
// Bitwise logic
//
case OP_INVERT:
{
// (in - out)
if (stack.size() < 1)
return false;
valtype& vch = stacktop(-1);
for (int i = 0; i < vch.size(); i++)
vch[i] = ~vch[i];
}
break;
case OP_AND:
case OP_OR:
case OP_XOR:
{
// (x1 x2 - out)
if (stack.size() < 2)
return false;
valtype& vch1 = stacktop(-2);
valtype& vch2 = stacktop(-1);
MakeSameSize(vch1, vch2);
if (opcode == OP_AND)
{
for (int i = 0; i < vch1.size(); i++)
vch1[i] &= vch2[i];
}
else if (opcode == OP_OR)
{
for (int i = 0; i < vch1.size(); i++)
vch1[i] |= vch2[i];
}
else if (opcode == OP_XOR)
{
for (int i = 0; i < vch1.size(); i++)
vch1[i] ^= vch2[i];
}
popstack(stack);
}
break;
case OP_EQUAL:
case OP_EQUALVERIFY:
//case OP_NOTEQUAL: // use OP_NUMNOTEQUAL
{
// (x1 x2 - bool)
if (stack.size() < 2)
return false;
valtype& vch1 = stacktop(-2);
valtype& vch2 = stacktop(-1);
bool fEqual = (vch1 == vch2);
// OP_NOTEQUAL is disabled because it would be too easy to say
// something like n != 1 and have some wiseguy pass in 1 with extra
// zero bytes after it (numerically, 0x01 == 0x0001 == 0x000001)
//if (opcode == OP_NOTEQUAL)
// fEqual = !fEqual;
popstack(stack);
popstack(stack);
stack.push_back(fEqual ? vchTrue : vchFalse);
if (opcode == OP_EQUALVERIFY)
{
if (fEqual)
popstack(stack);
else
return false;
}
}
break;
//
// Numeric
//
case OP_1ADD:
case OP_1SUB:
case OP_2MUL:
case OP_2DIV:
case OP_NEGATE:
case OP_ABS:
case OP_NOT:
case OP_0NOTEQUAL:
{
// (in -- out)
if (stack.size() < 1)
return false;
CBigNum bn = CastToBigNum(stacktop(-1));
switch (opcode)
{
case OP_1ADD: bn += bnOne; break;
case OP_1SUB: bn -= bnOne; break;
case OP_2MUL: bn <<= 1; break;
case OP_2DIV: bn >>= 1; break;
case OP_NEGATE: bn = -bn; break;
case OP_ABS: if (bn < bnZero) bn = -bn; break;
case OP_NOT: bn = (bn == bnZero); break;
case OP_0NOTEQUAL: bn = (bn != bnZero); break;
default: assert(!"invalid opcode"); break;
}
popstack(stack);
stack.push_back(bn.getvch());
}
break;
case OP_ADD:
case OP_SUB:
case OP_MUL:
case OP_DIV:
case OP_MOD:
case OP_LSHIFT:
case OP_RSHIFT:
case OP_BOOLAND:
case OP_BOOLOR:
case OP_NUMEQUAL:
case OP_NUMEQUALVERIFY:
case OP_NUMNOTEQUAL:
case OP_LESSTHAN:
case OP_GREATERTHAN:
case OP_LESSTHANOREQUAL:
case OP_GREATERTHANOREQUAL:
case OP_MIN:
case OP_MAX:
{
// (x1 x2 -- out)
if (stack.size() < 2)
return false;
CBigNum bn1 = CastToBigNum(stacktop(-2));
CBigNum bn2 = CastToBigNum(stacktop(-1));
CBigNum bn;
switch (opcode)
{
case OP_ADD:
bn = bn1 + bn2;
break;
case OP_SUB:
bn = bn1 - bn2;
break;
case OP_MUL:
if (!BN_mul(&bn, &bn1, &bn2, pctx))
return false;
break;
case OP_DIV:
if (!BN_div(&bn, NULL, &bn1, &bn2, pctx))
return false;
break;
case OP_MOD:
if (!BN_mod(&bn, &bn1, &bn2, pctx))
return false;
break;
case OP_LSHIFT:
if (bn2 < bnZero || bn2 > CBigNum(2048))
return false;
bn = bn1 << bn2.getulong();
break;
case OP_RSHIFT:
if (bn2 < bnZero || bn2 > CBigNum(2048))
return false;
bn = bn1 >> bn2.getulong();
break;
case OP_BOOLAND: bn = (bn1 != bnZero && bn2 != bnZero); break;
case OP_BOOLOR: bn = (bn1 != bnZero || bn2 != bnZero); break;
case OP_NUMEQUAL: bn = (bn1 == bn2); break;
case OP_NUMEQUALVERIFY: bn = (bn1 == bn2); break;
case OP_NUMNOTEQUAL: bn = (bn1 != bn2); break;
case OP_LESSTHAN: bn = (bn1 < bn2); break;
case OP_GREATERTHAN: bn = (bn1 > bn2); break;
case OP_LESSTHANOREQUAL: bn = (bn1 <= bn2); break;
case OP_GREATERTHANOREQUAL: bn = (bn1 >= bn2); break;
case OP_MIN: bn = (bn1 < bn2 ? bn1 : bn2); break;
case OP_MAX: bn = (bn1 > bn2 ? bn1 : bn2); break;
default: assert(!"invalid opcode"); break;
}
popstack(stack);
popstack(stack);
stack.push_back(bn.getvch());
if (opcode == OP_NUMEQUALVERIFY)
{
if (CastToBool(stacktop(-1)))
popstack(stack);
else
return false;
}
}
break;
case OP_WITHIN:
{
// (x min max -- out)
if (stack.size() < 3)
return false;
CBigNum bn1 = CastToBigNum(stacktop(-3));
CBigNum bn2 = CastToBigNum(stacktop(-2));
CBigNum bn3 = CastToBigNum(stacktop(-1));
bool fValue = (bn2 <= bn1 && bn1 < bn3);
popstack(stack);
popstack(stack);
popstack(stack);
stack.push_back(fValue ? vchTrue : vchFalse);
}
break;
//
// Crypto
//
case OP_RIPEMD160:
case OP_SHA1:
case OP_SHA256:
case OP_HASH160:
case OP_HASH256:
{
// (in -- hash)
if (stack.size() < 1)
return false;
valtype& vch = stacktop(-1);
valtype vchHash((opcode == OP_RIPEMD160 || opcode == OP_SHA1 || opcode == OP_HASH160) ? 20 : 32);
if (opcode == OP_RIPEMD160)
RIPEMD160(&vch[0], vch.size(), &vchHash[0]);
else if (opcode == OP_SHA1)
SHA1(&vch[0], vch.size(), &vchHash[0]);
else if (opcode == OP_SHA256)
SHA256(&vch[0], vch.size(), &vchHash[0]);
else if (opcode == OP_HASH160)
{
uint160 hash160 = Hash160(vch);
memcpy(&vchHash[0], &hash160, sizeof(hash160));
}
else if (opcode == OP_HASH256)
{
uint256 hash = Hash(vch.begin(), vch.end());
memcpy(&vchHash[0], &hash, sizeof(hash));
}
popstack(stack);
stack.push_back(vchHash);
}
break;
case OP_CODESEPARATOR:
{
// Hash starts after the code separator
pbegincodehash = pc;
}
break;
case OP_CHECKSIG:
case OP_CHECKSIGVERIFY:
{
// (sig pubkey -- bool)
if (stack.size() < 2)
return false;
valtype& vchSig = stacktop(-2);
valtype& vchPubKey = stacktop(-1);
////// debug print
//PrintHex(vchSig.begin(), vchSig.end(), "sig: %s\n");
//PrintHex(vchPubKey.begin(), vchPubKey.end(), "pubkey: %s\n");
// Subset of script starting at the most recent codeseparator
CScript scriptCode(pbegincodehash, pend);
// Drop the signature, since there's no way for a signature to sign itself
scriptCode.FindAndDelete(CScript(vchSig));
bool fSuccess = CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType);
popstack(stack);
popstack(stack);
stack.push_back(fSuccess ? vchTrue : vchFalse);
if (opcode == OP_CHECKSIGVERIFY)
{
if (fSuccess)
popstack(stack);
else
return false;
}
}
break;
case OP_CHECKMULTISIG:
case OP_CHECKMULTISIGVERIFY:
{
// ([sig ...] num_of_signatures [pubkey ...] num_of_pubkeys -- bool)
int i = 1;
if (stack.size() < i)
return false;
int nKeysCount = CastToBigNum(stacktop(-i)).getint();
if (nKeysCount < 0 || nKeysCount > 20)
return false;
nOpCount += nKeysCount;
if (nOpCount > 201)
return false;
int ikey = ++i;
i += nKeysCount;
if (stack.size() < i)
return false;
int nSigsCount = CastToBigNum(stacktop(-i)).getint();
if (nSigsCount < 0 || nSigsCount > nKeysCount)
return false;
int isig = ++i;
i += nSigsCount;
if (stack.size() < i)
return false;
// Subset of script starting at the most recent codeseparator
CScript scriptCode(pbegincodehash, pend);
// Drop the signatures, since there's no way for a signature to sign itself
for (int k = 0; k < nSigsCount; k++)
{
valtype& vchSig = stacktop(-isig-k);
scriptCode.FindAndDelete(CScript(vchSig));
}
bool fSuccess = true;
while (fSuccess && nSigsCount > 0)
{
valtype& vchSig = stacktop(-isig);
valtype& vchPubKey = stacktop(-ikey);
// Check signature
if (CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType))
{
isig++;
nSigsCount--;
}
ikey++;
nKeysCount--;
// If there are more signatures left than keys left,
// then too many signatures have failed
if (nSigsCount > nKeysCount)
fSuccess = false;
}
while (i-- > 0)
popstack(stack);
stack.push_back(fSuccess ? vchTrue : vchFalse);
if (opcode == OP_CHECKMULTISIGVERIFY)
{
if (fSuccess)
popstack(stack);
else
return false;
}
}
break;
default:
return false;
}
// Size limits
if (stack.size() + altstack.size() > 1000)
return false;
}
}
catch (...)
{
return false;
}
if (!vfExec.empty())
return false;
return true;
}
uint256 SignatureHash(CScript scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType)
{
if (nIn >= txTo.vin.size())
{
printf("ERROR: SignatureHash() : nIn=%d out of range\n", nIn);
return 1;
}
CTransaction txTmp(txTo);
// In case concatenating two scripts ends up with two codeseparators,
// or an extra one at the end, this prevents all those possible incompatibilities.
scriptCode.FindAndDelete(CScript(OP_CODESEPARATOR));
// Blank out other inputs' signatures
for (int i = 0; i < txTmp.vin.size(); i++)
txTmp.vin[i].scriptSig = CScript();
txTmp.vin[nIn].scriptSig = scriptCode;
// Blank out some of the outputs
if ((nHashType & 0x1f) == SIGHASH_NONE)
{
// Wildcard payee
txTmp.vout.clear();
// Let the others update at will
for (int i = 0; i < txTmp.vin.size(); i++)
if (i != nIn)
txTmp.vin[i].nSequence = 0;
}
else if ((nHashType & 0x1f) == SIGHASH_SINGLE)
{
// Only lock-in the txout payee at same index as txin
unsigned int nOut = nIn;
if (nOut >= txTmp.vout.size())
{
printf("ERROR: SignatureHash() : nOut=%d out of range\n", nOut);
return 1;
}
txTmp.vout.resize(nOut+1);
for (int i = 0; i < nOut; i++)
txTmp.vout[i].SetNull();
// Let the others update at will
for (int i = 0; i < txTmp.vin.size(); i++)
if (i != nIn)
txTmp.vin[i].nSequence = 0;
}
// Blank out other inputs completely, not recommended for open transactions
if (nHashType & SIGHASH_ANYONECANPAY)
{
txTmp.vin[0] = txTmp.vin[nIn];
txTmp.vin.resize(1);
}
// Serialize and hash
CDataStream ss(SER_GETHASH);
ss.reserve(10000);
ss << txTmp << nHashType;
return Hash(ss.begin(), ss.end());
}
bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode,
const CTransaction& txTo, unsigned int nIn, int nHashType)
{
CKey key;
if (!key.SetPubKey(vchPubKey))
return false;
// Hash type is one byte tacked on to the end of the signature
if (vchSig.empty())
return false;
if (nHashType == 0)
nHashType = vchSig.back();
else if (nHashType != vchSig.back())
return false;
vchSig.pop_back();
return key.Verify(SignatureHash(scriptCode, txTo, nIn, nHashType), vchSig);
}
bool Solver(const CScript& scriptPubKey, vector<pair<opcodetype, valtype> >& vSolutionRet)
{
// Templates
static vector<CScript> vTemplates;
if (vTemplates.empty())
{
// Standard tx, sender provides pubkey, receiver adds signature
vTemplates.push_back(CScript() << OP_PUBKEY << OP_CHECKSIG);
// Bitcoin address tx, sender provides hash of pubkey, receiver provides signature and pubkey
vTemplates.push_back(CScript() << OP_DUP << OP_HASH160 << OP_PUBKEYHASH << OP_EQUALVERIFY << OP_CHECKSIG);
}
// Scan templates
const CScript& script1 = scriptPubKey;
BOOST_FOREACH(const CScript& script2, vTemplates)
{
vSolutionRet.clear();
opcodetype opcode1, opcode2;
vector<unsigned char> vch1, vch2;
// Compare
CScript::const_iterator pc1 = script1.begin();
CScript::const_iterator pc2 = script2.begin();
loop
{
if (pc1 == script1.end() && pc2 == script2.end())
{
// Found a match
reverse(vSolutionRet.begin(), vSolutionRet.end());
return true;
}
if (!script1.GetOp(pc1, opcode1, vch1))
break;
if (!script2.GetOp(pc2, opcode2, vch2))
break;
if (opcode2 == OP_PUBKEY)
{
if (vch1.size() < 33 || vch1.size() > 120)
break;
vSolutionRet.push_back(make_pair(opcode2, vch1));
}
else if (opcode2 == OP_PUBKEYHASH)
{
if (vch1.size() != sizeof(uint160))
break;
vSolutionRet.push_back(make_pair(opcode2, vch1));
}
else if (opcode1 != opcode2 || vch1 != vch2)
{
break;
}
}
}
vSolutionRet.clear();
return false;
}
bool Solver(const CKeyStore& keystore, const CScript& scriptPubKey, uint256 hash, int nHashType, CScript& scriptSigRet)
{
scriptSigRet.clear();
vector<pair<opcodetype, valtype> > vSolution;
if (!Solver(scriptPubKey, vSolution))
return false;
// Compile solution
BOOST_FOREACH(PAIRTYPE(opcodetype, valtype)& item, vSolution)
{
if (item.first == OP_PUBKEY)
{
// Sign
const valtype& vchPubKey = item.second;
CKey key;
if (!keystore.GetKey(Hash160(vchPubKey), key))
return false;
if (key.GetPubKey() != vchPubKey)
return false;
if (hash != 0)
{
vector<unsigned char> vchSig;
if (!key.Sign(hash, vchSig))
return false;
vchSig.push_back((unsigned char)nHashType);
scriptSigRet << vchSig;
}
}
else if (item.first == OP_PUBKEYHASH)
{
// Sign and give pubkey
CKey key;
if (!keystore.GetKey(uint160(item.second), key))
return false;
if (hash != 0)
{
vector<unsigned char> vchSig;
if (!key.Sign(hash, vchSig))
return false;
vchSig.push_back((unsigned char)nHashType);
scriptSigRet << vchSig << key.GetPubKey();
}
}
else
{
return false;
}
}
return true;
}
bool IsStandard(const CScript& scriptPubKey)
{
vector<pair<opcodetype, valtype> > vSolution;
return Solver(scriptPubKey, vSolution);
}
bool IsMine(const CKeyStore &keystore, const CScript& scriptPubKey)
{
vector<pair<opcodetype, valtype> > vSolution;
if (!Solver(scriptPubKey, vSolution))
return false;
// Compile solution
BOOST_FOREACH(PAIRTYPE(opcodetype, valtype)& item, vSolution)
{
if (item.first == OP_PUBKEY)
{
const valtype& vchPubKey = item.second;
vector<unsigned char> vchPubKeyFound;
if (!keystore.GetPubKey(Hash160(vchPubKey), vchPubKeyFound))
return false;
if (vchPubKeyFound != vchPubKey)
return false;
}
else if (item.first == OP_PUBKEYHASH)
{
if (!keystore.HaveKey(uint160(item.second)))
return false;
}
else
{
return false;
}
}
return true;
}
bool static ExtractAddressInner(const CScript& scriptPubKey, const CKeyStore* keystore, CBitcoinAddress& addressRet)
{
vector<pair<opcodetype, valtype> > vSolution;
if (!Solver(scriptPubKey, vSolution))
return false;
BOOST_FOREACH(PAIRTYPE(opcodetype, valtype)& item, vSolution)
{
if (item.first == OP_PUBKEY)
addressRet.SetPubKey(item.second);
else if (item.first == OP_PUBKEYHASH)
addressRet.SetHash160((uint160)item.second);
if (keystore == NULL || keystore->HaveKey(addressRet))
return true;
}
return false;
}
bool ExtractAddress(const CScript& scriptPubKey, const CKeyStore* keystore, CBitcoinAddress& addressRet)
{
if (keystore)
return ExtractAddressInner(scriptPubKey, keystore, addressRet);
else
return ExtractAddressInner(scriptPubKey, NULL, addressRet);
return false;
}
bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn,
bool fValidatePayToScriptHash, int nHashType)
{
vector<vector<unsigned char> > stack, stackCopy;
if (!EvalScript(stack, scriptSig, txTo, nIn, nHashType))
return false;
if (fValidatePayToScriptHash)
stackCopy = stack;
if (!EvalScript(stack, scriptPubKey, txTo, nIn, nHashType))
return false;
if (stack.empty())
return false;
if (CastToBool(stack.back()) == false)
return false;
// Additional validation for spend-to-script-hash transactions:
if (fValidatePayToScriptHash && scriptPubKey.IsPayToScriptHash())
{
if (!scriptSig.IsPushOnly()) // scriptSig must be literals-only
return false; // or validation fails
const valtype& pubKeySerialized = stackCopy.back();
CScript pubKey2(pubKeySerialized.begin(), pubKeySerialized.end());
popstack(stackCopy);
if (!EvalScript(stackCopy, pubKey2, txTo, nIn, nHashType))
return false;
if (stackCopy.empty())
return false;
return CastToBool(stackCopy.back());
}
return true;
}
bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType, CScript scriptPrereq)
{
assert(nIn < txTo.vin.size());
CTxIn& txin = txTo.vin[nIn];
assert(txin.prevout.n < txFrom.vout.size());
const CTxOut& txout = txFrom.vout[txin.prevout.n];
// Leave out the signature from the hash, since a signature can't sign itself.
// The checksig op will also drop the signatures from its hash.
uint256 hash = SignatureHash(scriptPrereq + txout.scriptPubKey, txTo, nIn, nHashType);
if (!Solver(keystore, txout.scriptPubKey, hash, nHashType, txin.scriptSig))
return false;
txin.scriptSig = scriptPrereq + txin.scriptSig;
// Test solution
if (scriptPrereq.empty())
if (!VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, true, 0))
return false;
return true;
}
bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, bool fValidatePayToScriptHash, int nHashType)
{
assert(nIn < txTo.vin.size());
const CTxIn& txin = txTo.vin[nIn];
if (txin.prevout.n >= txFrom.vout.size())
return false;
const CTxOut& txout = txFrom.vout[txin.prevout.n];
if (txin.prevout.hash != txFrom.GetHash())
return false;
if (!VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, fValidatePayToScriptHash, nHashType))
return false;
return true;
}
int CScript::GetSigOpCount(bool fAccurate) const
{
int n = 0;
const_iterator pc = begin();
opcodetype lastOpcode = OP_INVALIDOPCODE;
while (pc < end())
{
opcodetype opcode;
if (!GetOp(pc, opcode))
break;
if (opcode == OP_CHECKSIG || opcode == OP_CHECKSIGVERIFY)
n++;
else if (opcode == OP_CHECKMULTISIG || opcode == OP_CHECKMULTISIGVERIFY)
{
if (fAccurate && lastOpcode >= OP_1 && lastOpcode <= OP_16)
n += DecodeOP_N(lastOpcode);
else
n += 20;
}
lastOpcode = opcode;
}
return n;
}
int CScript::GetSigOpCount(const CScript& scriptSig) const
{
if (!IsPayToScriptHash())
return GetSigOpCount(true);
// This is a pay-to-script-hash scriptPubKey;
// get the last item that the scriptSig
// pushes onto the stack:
const_iterator pc = scriptSig.begin();
vector<unsigned char> data;
while (pc < scriptSig.end())
{
opcodetype opcode;
if (!scriptSig.GetOp(pc, opcode, data))
return 0;
if (opcode > OP_16)
return 0;
}
/// ... and return its opcount:
CScript subscript(data.begin(), data.end());
return subscript.GetSigOpCount(true);
}
bool CScript::IsPayToScriptHash() const
{
// Extra-fast test for pay-to-script-hash CScripts:
return (this->size() == 23 &&
this->at(0) == OP_HASH160 &&
this->at(1) == 0x14 &&
this->at(22) == OP_EQUAL);
}
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