1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2012 The Bitcoin developers
3 // Distributed under the MIT/X11 software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5 #ifndef H_BITCOIN_SCRIPT
6 #define H_BITCOIN_SCRIPT
11 #include <boost/foreach.hpp>
16 typedef std::vector<uint8_t> valtype;
20 static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes
22 /** IsMine() return codes */
28 MINE_ALL = MINE_WATCH_ONLY | MINE_SPENDABLE
31 typedef uint8_t isminefilter;
33 /** Signature hash types/flags */
39 SIGHASH_ANYONECANPAY = 0x80
42 /** Script verification flags */
45 SCRIPT_VERIFY_NONE = 0,
46 SCRIPT_VERIFY_P2SH = (1U << 0), // evaluate P2SH (BIP16) subscripts
47 SCRIPT_VERIFY_STRICTENC = (1U << 1), // enforce strict conformance to DER and SEC2 for signatures and pubkeys
48 SCRIPT_VERIFY_LOW_S = (1U << 2), // enforce low S values in signatures (depends on STRICTENC)
49 SCRIPT_VERIFY_NOCACHE = (1U << 3), // do not store results in signature cache (but do query it)
50 SCRIPT_VERIFY_NULLDUMMY = (1U << 4) // verify dummy stack item consumed by CHECKMULTISIG is of zero-length
53 // Strict verification:
55 // * force DER encoding;
57 // * ensure that CHECKMULTISIG dummy argument is null.
58 static const unsigned int STRICT_FORMAT_FLAGS = SCRIPT_VERIFY_STRICTENC | SCRIPT_VERIFY_LOW_S | SCRIPT_VERIFY_NULLDUMMY;
60 // Mandatory script verification flags that all new blocks must comply with for
61 // them to be valid. (but old blocks may not comply with) Currently just P2SH,
62 // but in the future other flags may be added, such as a soft-fork to enforce
63 // strict DER encoding.
65 // Failing one of these tests may trigger a DoS ban - see ConnectInputs() for
67 static const unsigned int MANDATORY_SCRIPT_VERIFY_FLAGS = SCRIPT_VERIFY_P2SH;
69 // Standard script verification flags that standard transactions will comply
70 // with. However scripts violating these flags may still be present in valid
71 // blocks and we must accept those blocks.
72 static const unsigned int STRICT_FLAGS = MANDATORY_SCRIPT_VERIFY_FLAGS | STRICT_FORMAT_FLAGS;
77 // 'standard' transaction types:
85 const char* GetTxnOutputType(txnouttype t);
129 OP_TOALTSTACK = 0x6b,
130 OP_FROMALTSTACK = 0x6c,
162 OP_EQUALVERIFY = 0x88,
187 OP_NUMEQUALVERIFY = 0x9d,
188 OP_NUMNOTEQUAL = 0x9e,
190 OP_GREATERTHAN = 0xa0,
191 OP_LESSTHANOREQUAL = 0xa1,
192 OP_GREATERTHANOREQUAL = 0xa2,
204 OP_CODESEPARATOR = 0xab,
206 OP_CHECKSIGVERIFY = 0xad,
207 OP_CHECKMULTISIG = 0xae,
208 OP_CHECKMULTISIGVERIFY = 0xaf,
224 // template matching params
226 OP_SMALLINTEGER = 0xfa,
228 OP_PUBKEYHASH = 0xfd,
231 OP_INVALIDOPCODE = 0xff
234 const char* GetOpName(opcodetype opcode);
236 inline std::string ValueString(const std::vector<unsigned char>& vch)
239 return strprintf("%d", CBigNum(vch).getint32());
244 inline std::string StackString(const std::vector<std::vector<unsigned char> >& vStack)
247 BOOST_FOREACH(const std::vector<unsigned char>& vch, vStack)
251 str += ValueString(vch);
256 /** Serialized script, used inside transaction inputs and outputs */
257 class CScript : public std::vector<uint8_t>
260 CScript& push_int64(int64_t n)
262 if (n == -1 || (n >= 1 && n <= 16))
264 push_back((uint8_t)n + (OP_1 - 1));
269 *this << bn.getvch();
274 CScript& push_uint64(uint64_t n)
276 if (n >= 1 && n <= 16)
278 push_back((uint8_t)n + (OP_1 - 1));
283 *this << bn.getvch();
290 CScript(const CScript& b) : std::vector<uint8_t>(b.begin(), b.end()) { }
291 CScript(const_iterator pbegin, const_iterator pend) : std::vector<uint8_t>(pbegin, pend) { }
293 CScript(const uint8_t* pbegin, const uint8_t* pend) : std::vector<uint8_t>(pbegin, pend) { }
296 CScript& operator+=(const CScript& b)
298 insert(end(), b.begin(), b.end());
302 friend CScript operator+(const CScript& a, const CScript& b)
309 explicit CScript(int8_t b) { operator<<(b); }
310 explicit CScript(int16_t b) { operator<<(b); }
311 explicit CScript(int32_t b) { operator<<(b); }
312 explicit CScript(int64_t b) { operator<<(b); }
314 explicit CScript(uint8_t b) { operator<<(b); }
315 explicit CScript(uint16_t b) { operator<<(b); }
316 explicit CScript(uint32_t b) { operator<<(b); }
317 explicit CScript(uint64_t b) { operator<<(b); }
319 explicit CScript(opcodetype b) { operator<<(b); }
320 explicit CScript(const uint256& b) { operator<<(b); }
321 explicit CScript(const CBigNum& b) { operator<<(b); }
322 explicit CScript(const std::vector<uint8_t>& b) { operator<<(b); }
324 CScript& operator<<(int8_t b) { return push_int64(b); }
325 CScript& operator<<(int16_t b) { return push_int64(b); }
326 CScript& operator<<(int32_t b) { return push_int64(b); }
327 CScript& operator<<(int64_t b) { return push_int64(b); }
329 CScript& operator<<(uint8_t b) { return push_uint64(b); }
330 CScript& operator<<(uint16_t b) { return push_uint64(b); }
331 CScript& operator<<(uint32_t b) { return push_uint64(b); }
332 CScript& operator<<(uint64_t b) { return push_uint64(b); }
334 CScript& operator<<(opcodetype opcode)
336 if (opcode < 0 || opcode > 0xff)
337 throw std::runtime_error("CScript::operator<<() : invalid opcode");
338 insert(end(), (uint8_t)opcode);
342 CScript& operator<<(const uint160& b)
344 insert(end(), sizeof(b));
345 insert(end(), (uint8_t*)&b, (uint8_t*)&b + sizeof(b));
349 CScript& operator<<(const uint256& b)
351 insert(end(), sizeof(b));
352 insert(end(), (uint8_t*)&b, (uint8_t*)&b + sizeof(b));
356 CScript& operator<<(const CPubKey& key)
358 std::vector<uint8_t> vchKey = key.Raw();
359 return (*this) << vchKey;
362 CScript& operator<<(const CBigNum& b)
368 CScript& operator<<(const std::vector<uint8_t>& b)
370 if (b.size() < OP_PUSHDATA1)
372 insert(end(), (uint8_t)b.size());
374 else if (b.size() <= 0xff)
376 insert(end(), OP_PUSHDATA1);
377 insert(end(), (uint8_t)b.size());
379 else if (b.size() <= 0xffff)
381 insert(end(), OP_PUSHDATA2);
382 uint16_t nSize = (uint16_t) b.size();
383 insert(end(), (uint8_t*)&nSize, (uint8_t*)&nSize + sizeof(nSize));
387 insert(end(), OP_PUSHDATA4);
388 uint32_t nSize = (uint32_t) b.size();
389 insert(end(), (uint8_t*)&nSize, (uint8_t*)&nSize + sizeof(nSize));
391 insert(end(), b.begin(), b.end());
395 CScript& operator<<(const CScript& b)
397 // I'm not sure if this should push the script or concatenate scripts.
398 // If there's ever a use for pushing a script onto a script, delete this member fn
399 assert(!"Warning: Pushing a CScript onto a CScript with << is probably not intended, use + to concatenate!");
404 bool GetOp(iterator& pc, opcodetype& opcodeRet, std::vector<uint8_t>& vchRet)
406 // Wrapper so it can be called with either iterator or const_iterator
407 const_iterator pc2 = pc;
408 bool fRet = GetOp2(pc2, opcodeRet, &vchRet);
409 pc = begin() + (pc2 - begin());
413 bool GetOp(iterator& pc, opcodetype& opcodeRet)
415 const_iterator pc2 = pc;
416 bool fRet = GetOp2(pc2, opcodeRet, NULL);
417 pc = begin() + (pc2 - begin());
421 bool GetOp(const_iterator& pc, opcodetype& opcodeRet, std::vector<uint8_t>& vchRet) const
423 return GetOp2(pc, opcodeRet, &vchRet);
426 bool GetOp(const_iterator& pc, opcodetype& opcodeRet) const
428 return GetOp2(pc, opcodeRet, NULL);
431 bool GetOp2(const_iterator& pc, opcodetype& opcodeRet, std::vector<uint8_t>* pvchRet) const
433 opcodeRet = OP_INVALIDOPCODE;
442 uint32_t opcode = *pc++;
445 if (opcode <= OP_PUSHDATA4)
447 uint32_t nSize = OP_0;
448 if (opcode < OP_PUSHDATA1)
452 else if (opcode == OP_PUSHDATA1)
458 else if (opcode == OP_PUSHDATA2)
462 memcpy(&nSize, &pc[0], 2);
465 else if (opcode == OP_PUSHDATA4)
469 memcpy(&nSize, &pc[0], 4);
472 if (end() - pc < 0 || (uint32_t)(end() - pc) < nSize)
475 pvchRet->assign(pc, pc + nSize);
479 opcodeRet = (opcodetype)opcode;
483 // Encode/decode small integers:
484 static int DecodeOP_N(opcodetype opcode)
488 assert(opcode >= OP_1 && opcode <= OP_16);
489 return (opcode - (OP_1 - 1));
491 static opcodetype EncodeOP_N(int n)
493 assert(n >= 0 && n <= 16);
496 return (opcodetype)(OP_1+n-1);
499 int FindAndDelete(const CScript& b)
504 iterator pc = begin();
508 while (end() - pc >= (long)b.size() && memcmp(&pc[0], &b[0], b.size()) == 0)
510 erase(pc, pc + b.size());
514 while (GetOp(pc, opcode));
517 int Find(opcodetype op) const
521 for (const_iterator pc = begin(); pc != end() && GetOp(pc, opcode);)
527 // Pre-version-0.6, Bitcoin always counted CHECKMULTISIGs
528 // as 20 sigops. With pay-to-script-hash, that changed:
529 // CHECKMULTISIGs serialized in scriptSigs are
530 // counted more accurately, assuming they are of the form
531 // ... OP_N CHECKMULTISIG ...
532 unsigned int GetSigOpCount(bool fAccurate) const;
534 // Accurately count sigOps, including sigOps in
535 // pay-to-script-hash transactions:
536 unsigned int GetSigOpCount(const CScript& scriptSig) const;
538 bool IsPayToScriptHash() const;
540 // Called by CTransaction::IsStandard and P2SH VerifyScript (which makes it consensus-critical).
541 bool IsPushOnly() const
543 const_iterator pc = begin();
547 if (!GetOp(pc, opcode))
555 // Called by CTransaction::IsStandard.
556 bool HasCanonicalPushes() const;
558 void SetDestination(const CTxDestination& address);
559 void SetMultisig(int nRequired, const std::vector<CKey>& keys);
562 void PrintHex() const
564 printf("CScript(%s)\n", HexStr(begin(), end(), true).c_str());
567 std::string ToString(bool fShort=false) const
571 std::vector<uint8_t> vch;
572 const_iterator pc = begin();
577 if (!GetOp(pc, opcode, vch))
582 if (0 <= opcode && opcode <= OP_PUSHDATA4)
583 str += fShort? ValueString(vch).substr(0, 10) : ValueString(vch);
585 str += GetOpName(opcode);
592 printf("%s\n", ToString().c_str());
595 CScriptID GetID() const
597 return CScriptID(Hash160(*this));
601 bool IsCanonicalPubKey(const std::vector<unsigned char> &vchPubKey, unsigned int flags);
602 bool IsDERSignature(const valtype &vchSig, bool fWithHashType=false, bool fCheckLow=false);
603 bool IsCanonicalSignature(const std::vector<unsigned char> &vchSig, unsigned int flags);
605 bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType);
606 bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<std::vector<unsigned char> >& vSolutionsRet);
607 int ScriptSigArgsExpected(txnouttype t, const std::vector<std::vector<unsigned char> >& vSolutions);
608 bool IsStandard(const CScript& scriptPubKey, txnouttype& whichType);
609 isminetype IsMine(const CKeyStore& keystore, const CScript& scriptPubKey);
610 isminetype IsMine(const CKeyStore& keystore, const CTxDestination& dest);
611 void ExtractAffectedKeys(const CKeyStore &keystore, const CScript& scriptPubKey, std::vector<CKeyID> &vKeys);
612 bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet);
613 bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<CTxDestination>& addressRet, int& nRequiredRet);
614 bool SignSignature(const CKeyStore& keystore, const CScript& fromPubKey, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
615 bool SignSignature(const CKeyStore& keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
616 bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType);
618 // Given two sets of signatures for scriptPubKey, possibly with OP_0 placeholders,
619 // combine them intelligently and return the result.
620 CScript CombineSignatures(CScript scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CScript& scriptSig1, const CScript& scriptSig2);