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;
74 // Soft verifications, no extended signature format checkings
75 static const unsigned int SOFT_FLAGS = STRICT_FLAGS & ~STRICT_FORMAT_FLAGS;
80 // 'standard' transaction types:
88 const char* GetTxnOutputType(txnouttype t);
132 OP_TOALTSTACK = 0x6b,
133 OP_FROMALTSTACK = 0x6c,
165 OP_EQUALVERIFY = 0x88,
190 OP_NUMEQUALVERIFY = 0x9d,
191 OP_NUMNOTEQUAL = 0x9e,
193 OP_GREATERTHAN = 0xa0,
194 OP_LESSTHANOREQUAL = 0xa1,
195 OP_GREATERTHANOREQUAL = 0xa2,
207 OP_CODESEPARATOR = 0xab,
209 OP_CHECKSIGVERIFY = 0xad,
210 OP_CHECKMULTISIG = 0xae,
211 OP_CHECKMULTISIGVERIFY = 0xaf,
227 // template matching params
229 OP_SMALLINTEGER = 0xfa,
231 OP_PUBKEYHASH = 0xfd,
234 OP_INVALIDOPCODE = 0xff,
237 const char* GetOpName(opcodetype opcode);
239 inline std::string ValueString(const std::vector<unsigned char>& vch)
242 return strprintf("%d", CBigNum(vch).getint32());
247 inline std::string StackString(const std::vector<std::vector<unsigned char> >& vStack)
250 BOOST_FOREACH(const std::vector<unsigned char>& vch, vStack)
254 str += ValueString(vch);
259 /** Serialized script, used inside transaction inputs and outputs */
260 class CScript : public std::vector<uint8_t>
263 CScript& push_int64(int64_t n)
265 if (n == -1 || (n >= 1 && n <= 16))
267 push_back((uint8_t)n + (OP_1 - 1));
272 *this << bn.getvch();
277 CScript& push_uint64(uint64_t n)
279 if (n >= 1 && n <= 16)
281 push_back((uint8_t)n + (OP_1 - 1));
286 *this << bn.getvch();
293 CScript(const CScript& b) : std::vector<uint8_t>(b.begin(), b.end()) { }
294 CScript(const_iterator pbegin, const_iterator pend) : std::vector<uint8_t>(pbegin, pend) { }
296 CScript(const uint8_t* pbegin, const uint8_t* pend) : std::vector<uint8_t>(pbegin, pend) { }
299 CScript& operator+=(const CScript& b)
301 insert(end(), b.begin(), b.end());
305 friend CScript operator+(const CScript& a, const CScript& b)
312 explicit CScript(int8_t b) { operator<<(b); }
313 explicit CScript(int16_t b) { operator<<(b); }
314 explicit CScript(int32_t b) { operator<<(b); }
315 explicit CScript(int64_t b) { operator<<(b); }
317 explicit CScript(uint8_t b) { operator<<(b); }
318 explicit CScript(uint16_t b) { operator<<(b); }
319 explicit CScript(uint32_t b) { operator<<(b); }
320 explicit CScript(uint64_t b) { operator<<(b); }
322 explicit CScript(opcodetype b) { operator<<(b); }
323 explicit CScript(const uint256& b) { operator<<(b); }
324 explicit CScript(const CBigNum& b) { operator<<(b); }
325 explicit CScript(const std::vector<uint8_t>& b) { operator<<(b); }
327 CScript& operator<<(int8_t b) { return push_int64(b); }
328 CScript& operator<<(int16_t b) { return push_int64(b); }
329 CScript& operator<<(int32_t b) { return push_int64(b); }
330 CScript& operator<<(int64_t b) { return push_int64(b); }
332 CScript& operator<<(uint8_t b) { return push_uint64(b); }
333 CScript& operator<<(uint16_t b) { return push_uint64(b); }
334 CScript& operator<<(uint32_t b) { return push_uint64(b); }
335 CScript& operator<<(uint64_t b) { return push_uint64(b); }
337 CScript& operator<<(opcodetype opcode)
339 if (opcode < 0 || opcode > 0xff)
340 throw std::runtime_error("CScript::operator<<() : invalid opcode");
341 insert(end(), (uint8_t)opcode);
345 CScript& operator<<(const uint160& b)
347 insert(end(), sizeof(b));
348 insert(end(), (uint8_t*)&b, (uint8_t*)&b + sizeof(b));
352 CScript& operator<<(const uint256& b)
354 insert(end(), sizeof(b));
355 insert(end(), (uint8_t*)&b, (uint8_t*)&b + sizeof(b));
359 CScript& operator<<(const CPubKey& key)
361 std::vector<uint8_t> vchKey = key.Raw();
362 return (*this) << vchKey;
365 CScript& operator<<(const CBigNum& b)
371 CScript& operator<<(const std::vector<uint8_t>& b)
373 if (b.size() < OP_PUSHDATA1)
375 insert(end(), (uint8_t)b.size());
377 else if (b.size() <= 0xff)
379 insert(end(), OP_PUSHDATA1);
380 insert(end(), (uint8_t)b.size());
382 else if (b.size() <= 0xffff)
384 insert(end(), OP_PUSHDATA2);
385 uint16_t nSize = (uint16_t) b.size();
386 insert(end(), (uint8_t*)&nSize, (uint8_t*)&nSize + sizeof(nSize));
390 insert(end(), OP_PUSHDATA4);
391 uint32_t nSize = (uint32_t) b.size();
392 insert(end(), (uint8_t*)&nSize, (uint8_t*)&nSize + sizeof(nSize));
394 insert(end(), b.begin(), b.end());
398 CScript& operator<<(const CScript& b)
400 // I'm not sure if this should push the script or concatenate scripts.
401 // If there's ever a use for pushing a script onto a script, delete this member fn
402 assert(!"Warning: Pushing a CScript onto a CScript with << is probably not intended, use + to concatenate!");
407 bool GetOp(iterator& pc, opcodetype& opcodeRet, std::vector<uint8_t>& vchRet)
409 // Wrapper so it can be called with either iterator or const_iterator
410 const_iterator pc2 = pc;
411 bool fRet = GetOp2(pc2, opcodeRet, &vchRet);
412 pc = begin() + (pc2 - begin());
416 bool GetOp(iterator& pc, opcodetype& opcodeRet)
418 const_iterator pc2 = pc;
419 bool fRet = GetOp2(pc2, opcodeRet, NULL);
420 pc = begin() + (pc2 - begin());
424 bool GetOp(const_iterator& pc, opcodetype& opcodeRet, std::vector<uint8_t>& vchRet) const
426 return GetOp2(pc, opcodeRet, &vchRet);
429 bool GetOp(const_iterator& pc, opcodetype& opcodeRet) const
431 return GetOp2(pc, opcodeRet, NULL);
434 bool GetOp2(const_iterator& pc, opcodetype& opcodeRet, std::vector<uint8_t>* pvchRet) const
436 opcodeRet = OP_INVALIDOPCODE;
445 uint32_t opcode = *pc++;
448 if (opcode <= OP_PUSHDATA4)
451 if (opcode < OP_PUSHDATA1)
455 else if (opcode == OP_PUSHDATA1)
461 else if (opcode == OP_PUSHDATA2)
466 memcpy(&nSize, &pc[0], 2);
469 else if (opcode == OP_PUSHDATA4)
473 memcpy(&nSize, &pc[0], 4);
476 if (end() - pc < 0 || (uint32_t)(end() - pc) < nSize)
479 pvchRet->assign(pc, pc + nSize);
483 opcodeRet = (opcodetype)opcode;
487 // Encode/decode small integers:
488 static int DecodeOP_N(opcodetype opcode)
492 assert(opcode >= OP_1 && opcode <= OP_16);
493 return (int)opcode - (int)(OP_1 - 1);
495 static opcodetype EncodeOP_N(int n)
497 assert(n >= 0 && n <= 16);
500 return (opcodetype)(OP_1+n-1);
503 int FindAndDelete(const CScript& b)
508 iterator pc = begin();
512 while (end() - pc >= (long)b.size() && memcmp(&pc[0], &b[0], b.size()) == 0)
514 erase(pc, pc + b.size());
518 while (GetOp(pc, opcode));
521 int Find(opcodetype op) const
525 for (const_iterator pc = begin(); pc != end() && GetOp(pc, opcode);)
531 // Pre-version-0.6, Bitcoin always counted CHECKMULTISIGs
532 // as 20 sigops. With pay-to-script-hash, that changed:
533 // CHECKMULTISIGs serialized in scriptSigs are
534 // counted more accurately, assuming they are of the form
535 // ... OP_N CHECKMULTISIG ...
536 unsigned int GetSigOpCount(bool fAccurate) const;
538 // Accurately count sigOps, including sigOps in
539 // pay-to-script-hash transactions:
540 unsigned int GetSigOpCount(const CScript& scriptSig) const;
542 bool IsPayToScriptHash() const;
544 // Called by CTransaction::IsStandard and P2SH VerifyScript (which makes it consensus-critical).
545 bool IsPushOnly() const
547 const_iterator pc = begin();
551 if (!GetOp(pc, opcode))
559 // Called by CTransaction::IsStandard.
560 bool HasCanonicalPushes() const;
562 void SetDestination(const CTxDestination& address);
563 void SetMultisig(int nRequired, const std::vector<CKey>& keys);
566 void PrintHex() const
568 printf("CScript(%s)\n", HexStr(begin(), end(), true).c_str());
571 std::string ToString(bool fShort=false) const
575 std::vector<uint8_t> vch;
576 const_iterator pc = begin();
581 if (!GetOp(pc, opcode, vch))
586 if (0 <= opcode && opcode <= OP_PUSHDATA4)
587 str += fShort? ValueString(vch).substr(0, 10) : ValueString(vch);
589 str += GetOpName(opcode);
596 printf("%s\n", ToString().c_str());
599 CScriptID GetID() const
601 return CScriptID(Hash160(*this));
605 bool IsCanonicalPubKey(const std::vector<unsigned char> &vchPubKey, unsigned int flags);
606 bool IsCanonicalSignature(const std::vector<unsigned char> &vchSig, unsigned int flags);
609 bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType);
610 bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<std::vector<unsigned char> >& vSolutionsRet);
611 int ScriptSigArgsExpected(txnouttype t, const std::vector<std::vector<unsigned char> >& vSolutions);
612 bool IsStandard(const CScript& scriptPubKey, txnouttype& whichType);
613 isminetype IsMine(const CKeyStore& keystore, const CScript& scriptPubKey);
614 isminetype IsMine(const CKeyStore& keystore, const CTxDestination& dest);
615 void ExtractAffectedKeys(const CKeyStore &keystore, const CScript& scriptPubKey, std::vector<CKeyID> &vKeys);
616 bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet);
617 bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<CTxDestination>& addressRet, int& nRequiredRet);
618 bool SignSignature(const CKeyStore& keystore, const CScript& fromPubKey, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
619 bool SignSignature(const CKeyStore& keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
620 bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType);
622 // Given two sets of signatures for scriptPubKey, possibly with OP_0 placeholders,
623 // combine them intelligently and return the result.
624 CScript CombineSignatures(CScript scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CScript& scriptSig1, const CScript& scriptSig2);