src/script.h

   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
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include <boost/foreach.hpp>
  12 #include <boost/variant.hpp>
  13
  14 #include "keystore.h"
  15 #include "bignum.h"
  16
  17 class CTransaction;
  18
  19 /** Signature hash types/flags */
  20 enum
  21 {
  22     SIGHASH_ALL = 1,
  23     SIGHASH_NONE = 2,
  24     SIGHASH_SINGLE = 3,
  25     SIGHASH_ANYONECANPAY = 0x80,
  26 };
  27
  28
  29 enum txnouttype
  30 {
  31     TX_NONSTANDARD,
  32     // 'standard' transaction types:
  33     TX_PUBKEY,
  34     TX_PUBKEYHASH,
  35     TX_SCRIPTHASH,
  36     TX_MULTISIG,
  37 };
  38
  39 class CNoDestination {
  40 public:
  41     friend bool operator==(const CNoDestination &a, const CNoDestination &b) { return true; }
  42     friend bool operator<(const CNoDestination &a, const CNoDestination &b) { return true; }
  43 };
  44
  45 /** A txout script template with a specific destination. It is either:
  46  *  * CNoDestination: no destination set
  47  *  * CKeyID: TX_PUBKEYHASH destination
  48  *  * CScriptID: TX_SCRIPTHASH destination
  49  *  A CTxDestination is the internal data type encoded in a CBitcoinAddress
  50  */
  51 typedef boost::variant<CNoDestination, CKeyID, CScriptID> CTxDestination;
  52
  53 const char* GetTxnOutputType(txnouttype t);
  54
  55 /** Script opcodes */
  56 enum opcodetype
  57 {
  58     // push value
  59     OP_0 = 0x00,
  60     OP_FALSE = OP_0,
  61     OP_PUSHDATA1 = 0x4c,
  62     OP_PUSHDATA2 = 0x4d,
  63     OP_PUSHDATA4 = 0x4e,
  64     OP_1NEGATE = 0x4f,
  65     OP_RESERVED = 0x50,
  66     OP_1 = 0x51,
  67     OP_TRUE=OP_1,
  68     OP_2 = 0x52,
  69     OP_3 = 0x53,
  70     OP_4 = 0x54,
  71     OP_5 = 0x55,
  72     OP_6 = 0x56,
  73     OP_7 = 0x57,
  74     OP_8 = 0x58,
  75     OP_9 = 0x59,
  76     OP_10 = 0x5a,
  77     OP_11 = 0x5b,
  78     OP_12 = 0x5c,
  79     OP_13 = 0x5d,
  80     OP_14 = 0x5e,
  81     OP_15 = 0x5f,
  82     OP_16 = 0x60,
  83
  84     // control
  85     OP_NOP = 0x61,
  86     OP_VER = 0x62,
  87     OP_IF = 0x63,
  88     OP_NOTIF = 0x64,
  89     OP_VERIF = 0x65,
  90     OP_VERNOTIF = 0x66,
  91     OP_ELSE = 0x67,
  92     OP_ENDIF = 0x68,
  93     OP_VERIFY = 0x69,
  94     OP_RETURN = 0x6a,
  95
  96     // stack ops
  97     OP_TOALTSTACK = 0x6b,
  98     OP_FROMALTSTACK = 0x6c,
  99     OP_2DROP = 0x6d,
 100     OP_2DUP = 0x6e,
 101     OP_3DUP = 0x6f,
 102     OP_2OVER = 0x70,
 103     OP_2ROT = 0x71,
 104     OP_2SWAP = 0x72,
 105     OP_IFDUP = 0x73,
 106     OP_DEPTH = 0x74,
 107     OP_DROP = 0x75,
 108     OP_DUP = 0x76,
 109     OP_NIP = 0x77,
 110     OP_OVER = 0x78,
 111     OP_PICK = 0x79,
 112     OP_ROLL = 0x7a,
 113     OP_ROT = 0x7b,
 114     OP_SWAP = 0x7c,
 115     OP_TUCK = 0x7d,
 116
 117     // splice ops
 118     OP_CAT = 0x7e,
 119     OP_SUBSTR = 0x7f,
 120     OP_LEFT = 0x80,
 121     OP_RIGHT = 0x81,
 122     OP_SIZE = 0x82,
 123
 124     // bit logic
 125     OP_INVERT = 0x83,
 126     OP_AND = 0x84,
 127     OP_OR = 0x85,
 128     OP_XOR = 0x86,
 129     OP_EQUAL = 0x87,
 130     OP_EQUALVERIFY = 0x88,
 131     OP_RESERVED1 = 0x89,
 132     OP_RESERVED2 = 0x8a,
 133
 134     // numeric
 135     OP_1ADD = 0x8b,
 136     OP_1SUB = 0x8c,
 137     OP_2MUL = 0x8d,
 138     OP_2DIV = 0x8e,
 139     OP_NEGATE = 0x8f,
 140     OP_ABS = 0x90,
 141     OP_NOT = 0x91,
 142     OP_0NOTEQUAL = 0x92,
 143
 144     OP_ADD = 0x93,
 145     OP_SUB = 0x94,
 146     OP_MUL = 0x95,
 147     OP_DIV = 0x96,
 148     OP_MOD = 0x97,
 149     OP_LSHIFT = 0x98,
 150     OP_RSHIFT = 0x99,
 151
 152     OP_BOOLAND = 0x9a,
 153     OP_BOOLOR = 0x9b,
 154     OP_NUMEQUAL = 0x9c,
 155     OP_NUMEQUALVERIFY = 0x9d,
 156     OP_NUMNOTEQUAL = 0x9e,
 157     OP_LESSTHAN = 0x9f,
 158     OP_GREATERTHAN = 0xa0,
 159     OP_LESSTHANOREQUAL = 0xa1,
 160     OP_GREATERTHANOREQUAL = 0xa2,
 161     OP_MIN = 0xa3,
 162     OP_MAX = 0xa4,
 163
 164     OP_WITHIN = 0xa5,
 165
 166     // crypto
 167     OP_RIPEMD160 = 0xa6,
 168     OP_SHA1 = 0xa7,
 169     OP_SHA256 = 0xa8,
 170     OP_HASH160 = 0xa9,
 171     OP_HASH256 = 0xaa,
 172     OP_CODESEPARATOR = 0xab,
 173     OP_CHECKSIG = 0xac,
 174     OP_CHECKSIGVERIFY = 0xad,
 175     OP_CHECKMULTISIG = 0xae,
 176     OP_CHECKMULTISIGVERIFY = 0xaf,
 177
 178     // expansion
 179     OP_NOP1 = 0xb0,
 180     OP_NOP2 = 0xb1,
 181     OP_NOP3 = 0xb2,
 182     OP_NOP4 = 0xb3,
 183     OP_NOP5 = 0xb4,
 184     OP_NOP6 = 0xb5,
 185     OP_NOP7 = 0xb6,
 186     OP_NOP8 = 0xb7,
 187     OP_NOP9 = 0xb8,
 188     OP_NOP10 = 0xb9,
 189
 190
 191
 192     // template matching params
 193     OP_SMALLINTEGER = 0xfa,
 194     OP_PUBKEYS = 0xfb,
 195     OP_PUBKEYHASH = 0xfd,
 196     OP_PUBKEY = 0xfe,
 197
 198     OP_INVALIDOPCODE = 0xff,
 199 };
 200
 201 const char* GetOpName(opcodetype opcode);
 202
 203
 204
 205 inline std::string ValueString(const std::vector<unsigned char>& vch)
 206 {
 207     if (vch.size() <= 4)
 208         return strprintf("%d", CBigNum(vch).getint());
 209     else
 210         return HexStr(vch);
 211 }
 212
 213 inline std::string StackString(const std::vector<std::vector<unsigned char> >& vStack)
 214 {
 215     std::string str;
 216     BOOST_FOREACH(const std::vector<unsigned char>& vch, vStack)
 217     {
 218         if (!str.empty())
 219             str += " ";
 220         str += ValueString(vch);
 221     }
 222     return str;
 223 }
 224
 225
 226
 227
 228
 229
 230
 231
 232 /** Serialized script, used inside transaction inputs and outputs */
 233 class CScript : public std::vector<unsigned char>
 234 {
 235 protected:
 236     CScript& push_int64(int64 n)
 237     {
 238         if (n == -1 || (n >= 1 && n <= 16))
 239         {
 240             push_back(n + (OP_1 - 1));
 241         }
 242         else
 243         {
 244             CBigNum bn(n);
 245             *this << bn.getvch();
 246         }
 247         return *this;
 248     }
 249
 250     CScript& push_uint64(uint64 n)
 251     {
 252         if (n >= 1 && n <= 16)
 253         {
 254             push_back(n + (OP_1 - 1));
 255         }
 256         else
 257         {
 258             CBigNum bn(n);
 259             *this << bn.getvch();
 260         }
 261         return *this;
 262     }
 263
 264 public:
 265     CScript() { }
 266     CScript(const CScript& b) : std::vector<unsigned char>(b.begin(), b.end()) { }
 267     CScript(const_iterator pbegin, const_iterator pend) : std::vector<unsigned char>(pbegin, pend) { }
 268 #ifndef _MSC_VER
 269     CScript(const unsigned char* pbegin, const unsigned char* pend) : std::vector<unsigned char>(pbegin, pend) { }
 270 #endif
 271
 272     CScript& operator+=(const CScript& b)
 273     {
 274         insert(end(), b.begin(), b.end());
 275         return *this;
 276     }
 277
 278     friend CScript operator+(const CScript& a, const CScript& b)
 279     {
 280         CScript ret = a;
 281         ret += b;
 282         return ret;
 283     }
 284
 285
 286     //explicit CScript(char b) is not portable.  Use 'signed char' or 'unsigned char'.
 287     explicit CScript(signed char b)    { operator<<(b); }
 288     explicit CScript(short b)          { operator<<(b); }
 289     explicit CScript(int b)            { operator<<(b); }
 290     explicit CScript(long b)           { operator<<(b); }
 291     explicit CScript(int64 b)          { operator<<(b); }
 292     explicit CScript(unsigned char b)  { operator<<(b); }
 293     explicit CScript(unsigned int b)   { operator<<(b); }
 294     explicit CScript(unsigned short b) { operator<<(b); }
 295     explicit CScript(unsigned long b)  { operator<<(b); }
 296     explicit CScript(uint64 b)         { operator<<(b); }
 297
 298     explicit CScript(opcodetype b)     { operator<<(b); }
 299     explicit CScript(const uint256& b) { operator<<(b); }
 300     explicit CScript(const CBigNum& b) { operator<<(b); }
 301     explicit CScript(const std::vector<unsigned char>& b) { operator<<(b); }
 302
 303
 304     //CScript& operator<<(char b) is not portable.  Use 'signed char' or 'unsigned char'.
 305     CScript& operator<<(signed char b)    { return push_int64(b); }
 306     CScript& operator<<(short b)          { return push_int64(b); }
 307     CScript& operator<<(int b)            { return push_int64(b); }
 308     CScript& operator<<(long b)           { return push_int64(b); }
 309     CScript& operator<<(int64 b)          { return push_int64(b); }
 310     CScript& operator<<(unsigned char b)  { return push_uint64(b); }
 311     CScript& operator<<(unsigned int b)   { return push_uint64(b); }
 312     CScript& operator<<(unsigned short b) { return push_uint64(b); }
 313     CScript& operator<<(unsigned long b)  { return push_uint64(b); }
 314     CScript& operator<<(uint64 b)         { return push_uint64(b); }
 315
 316     CScript& operator<<(opcodetype opcode)
 317     {
 318         if (opcode < 0 || opcode > 0xff)
 319             throw std::runtime_error("CScript::operator<<() : invalid opcode");
 320         insert(end(), (unsigned char)opcode);
 321         return *this;
 322     }
 323
 324     CScript& operator<<(const uint160& b)
 325     {
 326         insert(end(), sizeof(b));
 327         insert(end(), (unsigned char*)&b, (unsigned char*)&b + sizeof(b));
 328         return *this;
 329     }
 330
 331     CScript& operator<<(const uint256& b)
 332     {
 333         insert(end(), sizeof(b));
 334         insert(end(), (unsigned char*)&b, (unsigned char*)&b + sizeof(b));
 335         return *this;
 336     }
 337
 338     CScript& operator<<(const CPubKey& key)
 339     {
 340         std::vector<unsigned char> vchKey = key.Raw();
 341         return (*this) << vchKey;
 342     }
 343
 344     CScript& operator<<(const CBigNum& b)
 345     {
 346         *this << b.getvch();
 347         return *this;
 348     }
 349
 350     CScript& operator<<(const std::vector<unsigned char>& b)
 351     {
 352         if (b.size() < OP_PUSHDATA1)
 353         {
 354             insert(end(), (unsigned char)b.size());
 355         }
 356         else if (b.size() <= 0xff)
 357         {
 358             insert(end(), OP_PUSHDATA1);
 359             insert(end(), (unsigned char)b.size());
 360         }
 361         else if (b.size() <= 0xffff)
 362         {
 363             insert(end(), OP_PUSHDATA2);
 364             unsigned short nSize = b.size();
 365             insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize));
 366         }
 367         else
 368         {
 369             insert(end(), OP_PUSHDATA4);
 370             unsigned int nSize = b.size();
 371             insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize));
 372         }
 373         insert(end(), b.begin(), b.end());
 374         return *this;
 375     }
 376
 377     CScript& operator<<(const CScript& b)
 378     {
 379         // I'm not sure if this should push the script or concatenate scripts.
 380         // If there's ever a use for pushing a script onto a script, delete this member fn
 381         assert(!"Warning: Pushing a CScript onto a CScript with << is probably not intended, use + to concatenate!");
 382         return *this;
 383     }
 384
 385
 386     bool GetOp(iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>& vchRet)
 387     {
 388          // Wrapper so it can be called with either iterator or const_iterator
 389          const_iterator pc2 = pc;
 390          bool fRet = GetOp2(pc2, opcodeRet, &vchRet);
 391          pc = begin() + (pc2 - begin());
 392          return fRet;
 393     }
 394
 395     bool GetOp(iterator& pc, opcodetype& opcodeRet)
 396     {
 397          const_iterator pc2 = pc;
 398          bool fRet = GetOp2(pc2, opcodeRet, NULL);
 399          pc = begin() + (pc2 - begin());
 400          return fRet;
 401     }
 402
 403     bool GetOp(const_iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>& vchRet) const
 404     {
 405         return GetOp2(pc, opcodeRet, &vchRet);
 406     }
 407
 408     bool GetOp(const_iterator& pc, opcodetype& opcodeRet) const
 409     {
 410         return GetOp2(pc, opcodeRet, NULL);
 411     }
 412
 413     bool GetOp2(const_iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>* pvchRet) const
 414     {
 415         opcodeRet = OP_INVALIDOPCODE;
 416         if (pvchRet)
 417             pvchRet->clear();
 418         if (pc >= end())
 419             return false;
 420
 421         // Read instruction
 422         if (end() - pc < 1)
 423             return false;
 424         unsigned int opcode = *pc++;
 425
 426         // Immediate operand
 427         if (opcode <= OP_PUSHDATA4)
 428         {
 429             unsigned int nSize;
 430             if (opcode < OP_PUSHDATA1)
 431             {
 432                 nSize = opcode;
 433             }
 434             else if (opcode == OP_PUSHDATA1)
 435             {
 436                 if (end() - pc < 1)
 437                     return false;
 438                 nSize = *pc++;
 439             }
 440             else if (opcode == OP_PUSHDATA2)
 441             {
 442                 if (end() - pc < 2)
 443                     return false;
 444                 nSize = 0;
 445                 memcpy(&nSize, &pc[0], 2);
 446                 pc += 2;
 447             }
 448             else if (opcode == OP_PUSHDATA4)
 449             {
 450                 if (end() - pc < 4)
 451                     return false;
 452                 memcpy(&nSize, &pc[0], 4);
 453                 pc += 4;
 454             }
 455             if (end() - pc < 0 || (unsigned int)(end() - pc) < nSize)
 456                 return false;
 457             if (pvchRet)
 458                 pvchRet->assign(pc, pc + nSize);
 459             pc += nSize;
 460         }
 461
 462         opcodeRet = (opcodetype)opcode;
 463         return true;
 464     }
 465
 466     // Encode/decode small integers:
 467     static int DecodeOP_N(opcodetype opcode)
 468     {
 469         if (opcode == OP_0)
 470             return 0;
 471         assert(opcode >= OP_1 && opcode <= OP_16);
 472         return (int)opcode - (int)(OP_1 - 1);
 473     }
 474     static opcodetype EncodeOP_N(int n)
 475     {
 476         assert(n >= 0 && n <= 16);
 477         if (n == 0)
 478             return OP_0;
 479         return (opcodetype)(OP_1+n-1);
 480     }
 481
 482     int FindAndDelete(const CScript& b)
 483     {
 484         int nFound = 0;
 485         if (b.empty())
 486             return nFound;
 487         iterator pc = begin();
 488         opcodetype opcode;
 489         do
 490         {
 491             while (end() - pc >= (long)b.size() && memcmp(&pc[0], &b[0], b.size()) == 0)
 492             {
 493                 erase(pc, pc + b.size());
 494                 ++nFound;
 495             }
 496         }
 497         while (GetOp(pc, opcode));
 498         return nFound;
 499     }
 500     int Find(opcodetype op) const
 501     {
 502         int nFound = 0;
 503         opcodetype opcode;
 504         for (const_iterator pc = begin(); pc != end() && GetOp(pc, opcode);)
 505             if (opcode == op)
 506                 ++nFound;
 507         return nFound;
 508     }
 509
 510     // Pre-version-0.6, Bitcoin always counted CHECKMULTISIGs
 511     // as 20 sigops. With pay-to-script-hash, that changed:
 512     // CHECKMULTISIGs serialized in scriptSigs are
 513     // counted more accurately, assuming they are of the form
 514     //  ... OP_N CHECKMULTISIG ...
 515     unsigned int GetSigOpCount(bool fAccurate) const;
 516
 517     // Accurately count sigOps, including sigOps in
 518     // pay-to-script-hash transactions:
 519     unsigned int GetSigOpCount(const CScript& scriptSig) const;
 520
 521     bool IsPayToScriptHash() const;
 522
 523     // Called by CTransaction::IsStandard
 524     bool IsPushOnly() const
 525     {
 526         const_iterator pc = begin();
 527         while (pc < end())
 528         {
 529             opcodetype opcode;
 530             if (!GetOp(pc, opcode))
 531                 return false;
 532             if (opcode > OP_16)
 533                 return false;
 534         }
 535         return true;
 536     }
 537
 538
 539     void SetDestination(const CTxDestination& address);
 540     void SetMultisig(int nRequired, const std::vector<CKey>& keys);
 541
 542
 543     void PrintHex() const
 544     {
 545         printf("CScript(%s)\n", HexStr(begin(), end(), true).c_str());
 546     }
 547
 548     std::string ToString() const
 549     {
 550         std::string str;
 551         opcodetype opcode;
 552         std::vector<unsigned char> vch;
 553         const_iterator pc = begin();
 554         while (pc < end())
 555         {
 556             if (!str.empty())
 557                 str += " ";
 558             if (!GetOp(pc, opcode, vch))
 559             {
 560                 str += "[error]";
 561                 return str;
 562             }
 563             if (0 <= opcode && opcode <= OP_PUSHDATA4)
 564                 str += ValueString(vch);
 565             else
 566                 str += GetOpName(opcode);
 567         }
 568         return str;
 569     }
 570
 571     void print() const
 572     {
 573         printf("%s\n", ToString().c_str());
 574     }
 575
 576     CScriptID GetID() const
 577     {
 578         return CScriptID(Hash160(*this));
 579     }
 580 };
 581
 582
 583
 584
 585
 586 bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType);
 587 bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<std::vector<unsigned char> >& vSolutionsRet);
 588 int ScriptSigArgsExpected(txnouttype t, const std::vector<std::vector<unsigned char> >& vSolutions);
 589 bool IsStandard(const CScript& scriptPubKey);
 590 bool IsMine(const CKeyStore& keystore, const CScript& scriptPubKey);
 591 bool IsMine(const CKeyStore& keystore, const CTxDestination &dest);
 592 bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet);
 593 bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<CTxDestination>& addressRet, int& nRequiredRet);
 594 bool SignSignature(const CKeyStore& keystore, const CScript& fromPubKey, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
 595 bool SignSignature(const CKeyStore& keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
 596 bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn,
 597                   bool fValidatePayToScriptHash, int nHashType);
 598 bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, bool fValidatePayToScriptHash, int nHashType);
 599
 600 // Given two sets of signatures for scriptPubKey, possibly with OP_0 placeholders,
 601 // combine them intelligently and return the result.
 602 CScript CombineSignatures(CScript scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CScript& scriptSig1, const CScript& scriptSig2);
 603
 604 #endif