Projects : bitcoin : bitcoin_system_compiler

bitcoin/src/script.cpp

Dir - Raw

1// Copyright (c) 2009-2010 Satoshi Nakamoto
2// Copyright (c) 2011 The Bitcoin developers
3// Distributed under the MIT/X11 software license, see the accompanying
4// file license.txt or http://www.opensource.org/licenses/mit-license.php.
5#include "headers.h"
6
7using namespace std;
8using namespace boost;
9
10bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType);
11
12
13
14typedef vector<unsigned char> valtype;
15static const valtype vchFalse(0);
16static const valtype vchZero(0);
17static const valtype vchTrue(1, 1);
18static const CBigNum bnZero(0);
19static const CBigNum bnOne(1);
20static const CBigNum bnFalse(0);
21static const CBigNum bnTrue(1);
22static const size_t nMaxNumSize = 4;
23
24
25CBigNum CastToBigNum(const valtype& vch)
26{
27 if (vch.size() > nMaxNumSize)
28 throw runtime_error("CastToBigNum() : overflow");
29 // Get rid of extra leading zeros
30 return CBigNum(CBigNum(vch).getvch());
31}
32
33bool CastToBool(const valtype& vch)
34{
35 for (int i = 0; i < vch.size(); i++)
36 {
37 if (vch[i] != 0)
38 {
39 // Can be negative zero
40 if (i == vch.size()-1 && vch[i] == 0x80)
41 return false;
42 return true;
43 }
44 }
45 return false;
46}
47
48void MakeSameSize(valtype& vch1, valtype& vch2)
49{
50 // Lengthen the shorter one
51 if (vch1.size() < vch2.size())
52 vch1.resize(vch2.size(), 0);
53 if (vch2.size() < vch1.size())
54 vch2.resize(vch1.size(), 0);
55}
56
57
58
59//
60// Script is a stack machine (like Forth) that evaluates a predicate
61// returning a bool indicating valid or not. There are no loops.
62//
63#define stacktop(i) (stack.at(stack.size()+(i)))
64#define altstacktop(i) (altstack.at(altstack.size()+(i)))
65static inline void popstack(vector<valtype>& stack)
66{
67 if (stack.empty())
68 throw runtime_error("popstack() : stack empty");
69 stack.pop_back();
70}
71
72
73bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType)
74{
75 CAutoBN_CTX pctx;
76 CScript::const_iterator pc = script.begin();
77 CScript::const_iterator pend = script.end();
78 CScript::const_iterator pbegincodehash = script.begin();
79 opcodetype opcode;
80 valtype vchPushValue;
81 vector<bool> vfExec;
82 vector<valtype> altstack;
83 if (script.size() > 10000)
84 return false;
85 int nOpCount = 0;
86
87
88 try
89 {
90 while (pc < pend)
91 {
92 bool fExec = !count(vfExec.begin(), vfExec.end(), false);
93
94 //
95 // Read instruction
96 //
97 if (!script.GetOp(pc, opcode, vchPushValue))
98 return false;
99 if (vchPushValue.size() > 520)
100 return false;
101 if (opcode > OP_16 && ++nOpCount > 201)
102 return false;
103
104 if (opcode == OP_CAT ||
105 opcode == OP_SUBSTR ||
106 opcode == OP_LEFT ||
107 opcode == OP_RIGHT ||
108 opcode == OP_INVERT ||
109 opcode == OP_AND ||
110 opcode == OP_OR ||
111 opcode == OP_XOR ||
112 opcode == OP_2MUL ||
113 opcode == OP_2DIV ||
114 opcode == OP_MUL ||
115 opcode == OP_DIV ||
116 opcode == OP_MOD ||
117 opcode == OP_LSHIFT ||
118 opcode == OP_RSHIFT)
119 return false;
120
121 if (fExec && 0 <= opcode && opcode <= OP_PUSHDATA4)
122 stack.push_back(vchPushValue);
123 else if (fExec || (OP_IF <= opcode && opcode <= OP_ENDIF))
124 switch (opcode)
125 {
126 //
127 // Push value
128 //
129 case OP_1NEGATE:
130 case OP_1:
131 case OP_2:
132 case OP_3:
133 case OP_4:
134 case OP_5:
135 case OP_6:
136 case OP_7:
137 case OP_8:
138 case OP_9:
139 case OP_10:
140 case OP_11:
141 case OP_12:
142 case OP_13:
143 case OP_14:
144 case OP_15:
145 case OP_16:
146 {
147 // ( -- value)
148 CBigNum bn((int)opcode - (int)(OP_1 - 1));
149 stack.push_back(bn.getvch());
150 }
151 break;
152
153
154 //
155 // Control
156 //
157 case OP_NOP:
158 case OP_NOP1: case OP_NOP2: case OP_NOP3: case OP_NOP4: case OP_NOP5:
159 case OP_NOP6: case OP_NOP7: case OP_NOP8: case OP_NOP9: case OP_NOP10:
160 break;
161
162 case OP_IF:
163 case OP_NOTIF:
164 {
165 // <expression> if [statements] [else [statements]] endif
166 bool fValue = false;
167 if (fExec)
168 {
169 if (stack.size() < 1)
170 return false;
171 valtype& vch = stacktop(-1);
172 fValue = CastToBool(vch);
173 if (opcode == OP_NOTIF)
174 fValue = !fValue;
175 popstack(stack);
176 }
177 vfExec.push_back(fValue);
178 }
179 break;
180
181 case OP_ELSE:
182 {
183 if (vfExec.empty())
184 return false;
185 vfExec.back() = !vfExec.back();
186 }
187 break;
188
189 case OP_ENDIF:
190 {
191 if (vfExec.empty())
192 return false;
193 vfExec.pop_back();
194 }
195 break;
196
197 case OP_VERIFY:
198 {
199 // (true -- ) or
200 // (false -- false) and return
201 if (stack.size() < 1)
202 return false;
203 bool fValue = CastToBool(stacktop(-1));
204 if (fValue)
205 popstack(stack);
206 else
207 return false;
208 }
209 break;
210
211 case OP_RETURN:
212 {
213 return false;
214 }
215 break;
216
217
218 //
219 // Stack ops
220 //
221 case OP_TOALTSTACK:
222 {
223 if (stack.size() < 1)
224 return false;
225 altstack.push_back(stacktop(-1));
226 popstack(stack);
227 }
228 break;
229
230 case OP_FROMALTSTACK:
231 {
232 if (altstack.size() < 1)
233 return false;
234 stack.push_back(altstacktop(-1));
235 popstack(altstack);
236 }
237 break;
238
239 case OP_2DROP:
240 {
241 // (x1 x2 -- )
242 if (stack.size() < 2)
243 return false;
244 popstack(stack);
245 popstack(stack);
246 }
247 break;
248
249 case OP_2DUP:
250 {
251 // (x1 x2 -- x1 x2 x1 x2)
252 if (stack.size() < 2)
253 return false;
254 valtype vch1 = stacktop(-2);
255 valtype vch2 = stacktop(-1);
256 stack.push_back(vch1);
257 stack.push_back(vch2);
258 }
259 break;
260
261 case OP_3DUP:
262 {
263 // (x1 x2 x3 -- x1 x2 x3 x1 x2 x3)
264 if (stack.size() < 3)
265 return false;
266 valtype vch1 = stacktop(-3);
267 valtype vch2 = stacktop(-2);
268 valtype vch3 = stacktop(-1);
269 stack.push_back(vch1);
270 stack.push_back(vch2);
271 stack.push_back(vch3);
272 }
273 break;
274
275 case OP_2OVER:
276 {
277 // (x1 x2 x3 x4 -- x1 x2 x3 x4 x1 x2)
278 if (stack.size() < 4)
279 return false;
280 valtype vch1 = stacktop(-4);
281 valtype vch2 = stacktop(-3);
282 stack.push_back(vch1);
283 stack.push_back(vch2);
284 }
285 break;
286
287 case OP_2ROT:
288 {
289 // (x1 x2 x3 x4 x5 x6 -- x3 x4 x5 x6 x1 x2)
290 if (stack.size() < 6)
291 return false;
292 valtype vch1 = stacktop(-6);
293 valtype vch2 = stacktop(-5);
294 stack.erase(stack.end()-6, stack.end()-4);
295 stack.push_back(vch1);
296 stack.push_back(vch2);
297 }
298 break;
299
300 case OP_2SWAP:
301 {
302 // (x1 x2 x3 x4 -- x3 x4 x1 x2)
303 if (stack.size() < 4)
304 return false;
305 swap(stacktop(-4), stacktop(-2));
306 swap(stacktop(-3), stacktop(-1));
307 }
308 break;
309
310 case OP_IFDUP:
311 {
312 // (x - 0 | x x)
313 if (stack.size() < 1)
314 return false;
315 valtype vch = stacktop(-1);
316 if (CastToBool(vch))
317 stack.push_back(vch);
318 }
319 break;
320
321 case OP_DEPTH:
322 {
323 // -- stacksize
324 CBigNum bn(stack.size());
325 stack.push_back(bn.getvch());
326 }
327 break;
328
329 case OP_DROP:
330 {
331 // (x -- )
332 if (stack.size() < 1)
333 return false;
334 popstack(stack);
335 }
336 break;
337
338 case OP_DUP:
339 {
340 // (x -- x x)
341 if (stack.size() < 1)
342 return false;
343 valtype vch = stacktop(-1);
344 stack.push_back(vch);
345 }
346 break;
347
348 case OP_NIP:
349 {
350 // (x1 x2 -- x2)
351 if (stack.size() < 2)
352 return false;
353 stack.erase(stack.end() - 2);
354 }
355 break;
356
357 case OP_OVER:
358 {
359 // (x1 x2 -- x1 x2 x1)
360 if (stack.size() < 2)
361 return false;
362 valtype vch = stacktop(-2);
363 stack.push_back(vch);
364 }
365 break;
366
367 case OP_PICK:
368 case OP_ROLL:
369 {
370 // (xn ... x2 x1 x0 n - xn ... x2 x1 x0 xn)
371 // (xn ... x2 x1 x0 n - ... x2 x1 x0 xn)
372 if (stack.size() < 2)
373 return false;
374 int n = CastToBigNum(stacktop(-1)).getint();
375 popstack(stack);
376 if (n < 0 || n >= stack.size())
377 return false;
378 valtype vch = stacktop(-n-1);
379 if (opcode == OP_ROLL)
380 stack.erase(stack.end()-n-1);
381 stack.push_back(vch);
382 }
383 break;
384
385 case OP_ROT:
386 {
387 // (x1 x2 x3 -- x2 x3 x1)
388 // x2 x1 x3 after first swap
389 // x2 x3 x1 after second swap
390 if (stack.size() < 3)
391 return false;
392 swap(stacktop(-3), stacktop(-2));
393 swap(stacktop(-2), stacktop(-1));
394 }
395 break;
396
397 case OP_SWAP:
398 {
399 // (x1 x2 -- x2 x1)
400 if (stack.size() < 2)
401 return false;
402 swap(stacktop(-2), stacktop(-1));
403 }
404 break;
405
406 case OP_TUCK:
407 {
408 // (x1 x2 -- x2 x1 x2)
409 if (stack.size() < 2)
410 return false;
411 valtype vch = stacktop(-1);
412 stack.insert(stack.end()-2, vch);
413 }
414 break;
415
416
417 //
418 // Splice ops
419 //
420 case OP_CAT:
421 {
422 // (x1 x2 -- out)
423 if (stack.size() < 2)
424 return false;
425 valtype& vch1 = stacktop(-2);
426 valtype& vch2 = stacktop(-1);
427 vch1.insert(vch1.end(), vch2.begin(), vch2.end());
428 popstack(stack);
429 if (stacktop(-1).size() > 520)
430 return false;
431 }
432 break;
433
434 case OP_SUBSTR:
435 {
436 // (in begin size -- out)
437 if (stack.size() < 3)
438 return false;
439 valtype& vch = stacktop(-3);
440 int nBegin = CastToBigNum(stacktop(-2)).getint();
441 int nEnd = nBegin + CastToBigNum(stacktop(-1)).getint();
442 if (nBegin < 0 || nEnd < nBegin)
443 return false;
444 if (nBegin > vch.size())
445 nBegin = vch.size();
446 if (nEnd > vch.size())
447 nEnd = vch.size();
448 vch.erase(vch.begin() + nEnd, vch.end());
449 vch.erase(vch.begin(), vch.begin() + nBegin);
450 popstack(stack);
451 popstack(stack);
452 }
453 break;
454
455 case OP_LEFT:
456 case OP_RIGHT:
457 {
458 // (in size -- out)
459 if (stack.size() < 2)
460 return false;
461 valtype& vch = stacktop(-2);
462 int nSize = CastToBigNum(stacktop(-1)).getint();
463 if (nSize < 0)
464 return false;
465 if (nSize > vch.size())
466 nSize = vch.size();
467 if (opcode == OP_LEFT)
468 vch.erase(vch.begin() + nSize, vch.end());
469 else
470 vch.erase(vch.begin(), vch.end() - nSize);
471 popstack(stack);
472 }
473 break;
474
475 case OP_SIZE:
476 {
477 // (in -- in size)
478 if (stack.size() < 1)
479 return false;
480 CBigNum bn(stacktop(-1).size());
481 stack.push_back(bn.getvch());
482 }
483 break;
484
485
486 //
487 // Bitwise logic
488 //
489 case OP_INVERT:
490 {
491 // (in - out)
492 if (stack.size() < 1)
493 return false;
494 valtype& vch = stacktop(-1);
495 for (int i = 0; i < vch.size(); i++)
496 vch[i] = ~vch[i];
497 }
498 break;
499
500 case OP_AND:
501 case OP_OR:
502 case OP_XOR:
503 {
504 // (x1 x2 - out)
505 if (stack.size() < 2)
506 return false;
507 valtype& vch1 = stacktop(-2);
508 valtype& vch2 = stacktop(-1);
509 MakeSameSize(vch1, vch2);
510 if (opcode == OP_AND)
511 {
512 for (int i = 0; i < vch1.size(); i++)
513 vch1[i] &= vch2[i];
514 }
515 else if (opcode == OP_OR)
516 {
517 for (int i = 0; i < vch1.size(); i++)
518 vch1[i] |= vch2[i];
519 }
520 else if (opcode == OP_XOR)
521 {
522 for (int i = 0; i < vch1.size(); i++)
523 vch1[i] ^= vch2[i];
524 }
525 popstack(stack);
526 }
527 break;
528
529 case OP_EQUAL:
530 case OP_EQUALVERIFY:
531 //case OP_NOTEQUAL: // use OP_NUMNOTEQUAL
532 {
533 // (x1 x2 - bool)
534 if (stack.size() < 2)
535 return false;
536 valtype& vch1 = stacktop(-2);
537 valtype& vch2 = stacktop(-1);
538 bool fEqual = (vch1 == vch2);
539 // OP_NOTEQUAL is disabled because it would be too easy to say
540 // something like n != 1 and have some wiseguy pass in 1 with extra
541 // zero bytes after it (numerically, 0x01 == 0x0001 == 0x000001)
542 //if (opcode == OP_NOTEQUAL)
543 // fEqual = !fEqual;
544 popstack(stack);
545 popstack(stack);
546 stack.push_back(fEqual ? vchTrue : vchFalse);
547 if (opcode == OP_EQUALVERIFY)
548 {
549 if (fEqual)
550 popstack(stack);
551 else
552 return false;
553 }
554 }
555 break;
556
557
558 //
559 // Numeric
560 //
561 case OP_1ADD:
562 case OP_1SUB:
563 case OP_2MUL:
564 case OP_2DIV:
565 case OP_NEGATE:
566 case OP_ABS:
567 case OP_NOT:
568 case OP_0NOTEQUAL:
569 {
570 // (in -- out)
571 if (stack.size() < 1)
572 return false;
573 CBigNum bn = CastToBigNum(stacktop(-1));
574 switch (opcode)
575 {
576 case OP_1ADD: bn += bnOne; break;
577 case OP_1SUB: bn -= bnOne; break;
578 case OP_2MUL: bn <<= 1; break;
579 case OP_2DIV: bn >>= 1; break;
580 case OP_NEGATE: bn = -bn; break;
581 case OP_ABS: if (bn < bnZero) bn = -bn; break;
582 case OP_NOT: bn = (bn == bnZero); break;
583 case OP_0NOTEQUAL: bn = (bn != bnZero); break;
584 default: assert(!"invalid opcode"); break;
585 }
586 popstack(stack);
587 stack.push_back(bn.getvch());
588 }
589 break;
590
591 case OP_ADD:
592 case OP_SUB:
593 case OP_MUL:
594 case OP_DIV:
595 case OP_MOD:
596 case OP_LSHIFT:
597 case OP_RSHIFT:
598 case OP_BOOLAND:
599 case OP_BOOLOR:
600 case OP_NUMEQUAL:
601 case OP_NUMEQUALVERIFY:
602 case OP_NUMNOTEQUAL:
603 case OP_LESSTHAN:
604 case OP_GREATERTHAN:
605 case OP_LESSTHANOREQUAL:
606 case OP_GREATERTHANOREQUAL:
607 case OP_MIN:
608 case OP_MAX:
609 {
610 // (x1 x2 -- out)
611 if (stack.size() < 2)
612 return false;
613 CBigNum bn1 = CastToBigNum(stacktop(-2));
614 CBigNum bn2 = CastToBigNum(stacktop(-1));
615 CBigNum bn;
616 switch (opcode)
617 {
618 case OP_ADD:
619 bn = bn1 + bn2;
620 break;
621
622 case OP_SUB:
623 bn = bn1 - bn2;
624 break;
625
626 case OP_MUL:
627 if (!BN_mul(&bn, &bn1, &bn2, pctx))
628 return false;
629 break;
630
631 case OP_DIV:
632 if (!BN_div(&bn, NULL, &bn1, &bn2, pctx))
633 return false;
634 break;
635
636 case OP_MOD:
637 if (!BN_mod(&bn, &bn1, &bn2, pctx))
638 return false;
639 break;
640
641 case OP_LSHIFT:
642 if (bn2 < bnZero || bn2 > CBigNum(2048))
643 return false;
644 bn = bn1 << bn2.getulong();
645 break;
646
647 case OP_RSHIFT:
648 if (bn2 < bnZero || bn2 > CBigNum(2048))
649 return false;
650 bn = bn1 >> bn2.getulong();
651 break;
652
653 case OP_BOOLAND: bn = (bn1 != bnZero && bn2 != bnZero); break;
654 case OP_BOOLOR: bn = (bn1 != bnZero || bn2 != bnZero); break;
655 case OP_NUMEQUAL: bn = (bn1 == bn2); break;
656 case OP_NUMEQUALVERIFY: bn = (bn1 == bn2); break;
657 case OP_NUMNOTEQUAL: bn = (bn1 != bn2); break;
658 case OP_LESSTHAN: bn = (bn1 < bn2); break;
659 case OP_GREATERTHAN: bn = (bn1 > bn2); break;
660 case OP_LESSTHANOREQUAL: bn = (bn1 <= bn2); break;
661 case OP_GREATERTHANOREQUAL: bn = (bn1 >= bn2); break;
662 case OP_MIN: bn = (bn1 < bn2 ? bn1 : bn2); break;
663 case OP_MAX: bn = (bn1 > bn2 ? bn1 : bn2); break;
664 default: assert(!"invalid opcode"); break;
665 }
666 popstack(stack);
667 popstack(stack);
668 stack.push_back(bn.getvch());
669
670 if (opcode == OP_NUMEQUALVERIFY)
671 {
672 if (CastToBool(stacktop(-1)))
673 popstack(stack);
674 else
675 return false;
676 }
677 }
678 break;
679
680 case OP_WITHIN:
681 {
682 // (x min max -- out)
683 if (stack.size() < 3)
684 return false;
685 CBigNum bn1 = CastToBigNum(stacktop(-3));
686 CBigNum bn2 = CastToBigNum(stacktop(-2));
687 CBigNum bn3 = CastToBigNum(stacktop(-1));
688 bool fValue = (bn2 <= bn1 && bn1 < bn3);
689 popstack(stack);
690 popstack(stack);
691 popstack(stack);
692 stack.push_back(fValue ? vchTrue : vchFalse);
693 }
694 break;
695
696
697 //
698 // Crypto
699 //
700 case OP_RIPEMD160:
701 case OP_SHA1:
702 case OP_SHA256:
703 case OP_HASH160:
704 case OP_HASH256:
705 {
706 // (in -- hash)
707 if (stack.size() < 1)
708 return false;
709 valtype& vch = stacktop(-1);
710 valtype vchHash((opcode == OP_RIPEMD160 || opcode == OP_SHA1 || opcode == OP_HASH160) ? 20 : 32);
711 if (opcode == OP_RIPEMD160)
712 RIPEMD160(&vch[0], vch.size(), &vchHash[0]);
713 else if (opcode == OP_SHA1)
714 SHA1(&vch[0], vch.size(), &vchHash[0]);
715 else if (opcode == OP_SHA256)
716 SHA256(&vch[0], vch.size(), &vchHash[0]);
717 else if (opcode == OP_HASH160)
718 {
719 uint160 hash160 = Hash160(vch);
720 memcpy(&vchHash[0], &hash160, sizeof(hash160));
721 }
722 else if (opcode == OP_HASH256)
723 {
724 uint256 hash = Hash(vch.begin(), vch.end());
725 memcpy(&vchHash[0], &hash, sizeof(hash));
726 }
727 popstack(stack);
728 stack.push_back(vchHash);
729 }
730 break;
731
732 case OP_CODESEPARATOR:
733 {
734 // Hash starts after the code separator
735 pbegincodehash = pc;
736 }
737 break;
738
739 case OP_CHECKSIG:
740 case OP_CHECKSIGVERIFY:
741 {
742 // (sig pubkey -- bool)
743 if (stack.size() < 2)
744 return false;
745
746 valtype& vchSig = stacktop(-2);
747 valtype& vchPubKey = stacktop(-1);
748
749 ////// debug print
750 //PrintHex(vchSig.begin(), vchSig.end(), "sig: %s\n");
751 //PrintHex(vchPubKey.begin(), vchPubKey.end(), "pubkey: %s\n");
752
753 // Subset of script starting at the most recent codeseparator
754 CScript scriptCode(pbegincodehash, pend);
755
756 // Drop the signature, since there's no way for a signature to sign itself
757 scriptCode.FindAndDelete(CScript(vchSig));
758
759 bool fSuccess = CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType);
760
761 popstack(stack);
762 popstack(stack);
763 stack.push_back(fSuccess ? vchTrue : vchFalse);
764 if (opcode == OP_CHECKSIGVERIFY)
765 {
766 if (fSuccess)
767 popstack(stack);
768 else
769 return false;
770 }
771 }
772 break;
773
774 case OP_CHECKMULTISIG:
775 case OP_CHECKMULTISIGVERIFY:
776 {
777 // ([sig ...] num_of_signatures [pubkey ...] num_of_pubkeys -- bool)
778
779 int i = 1;
780 if (stack.size() < i)
781 return false;
782
783 int nKeysCount = CastToBigNum(stacktop(-i)).getint();
784 if (nKeysCount < 0 || nKeysCount > 20)
785 return false;
786 nOpCount += nKeysCount;
787 if (nOpCount > 201)
788 return false;
789 int ikey = ++i;
790 i += nKeysCount;
791 if (stack.size() < i)
792 return false;
793
794 int nSigsCount = CastToBigNum(stacktop(-i)).getint();
795 if (nSigsCount < 0 || nSigsCount > nKeysCount)
796 return false;
797 int isig = ++i;
798 i += nSigsCount;
799 if (stack.size() < i)
800 return false;
801
802 // Subset of script starting at the most recent codeseparator
803 CScript scriptCode(pbegincodehash, pend);
804
805 // Drop the signatures, since there's no way for a signature to sign itself
806 for (int k = 0; k < nSigsCount; k++)
807 {
808 valtype& vchSig = stacktop(-isig-k);
809 scriptCode.FindAndDelete(CScript(vchSig));
810 }
811
812 bool fSuccess = true;
813 while (fSuccess && nSigsCount > 0)
814 {
815 valtype& vchSig = stacktop(-isig);
816 valtype& vchPubKey = stacktop(-ikey);
817
818 // Check signature
819 if (CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType))
820 {
821 isig++;
822 nSigsCount--;
823 }
824 ikey++;
825 nKeysCount--;
826
827 // If there are more signatures left than keys left,
828 // then too many signatures have failed
829 if (nSigsCount > nKeysCount)
830 fSuccess = false;
831 }
832
833 while (i-- > 0)
834 popstack(stack);
835 stack.push_back(fSuccess ? vchTrue : vchFalse);
836
837 if (opcode == OP_CHECKMULTISIGVERIFY)
838 {
839 if (fSuccess)
840 popstack(stack);
841 else
842 return false;
843 }
844 }
845 break;
846
847 default:
848 return false;
849 }
850
851 // Size limits
852 if (stack.size() + altstack.size() > 1000)
853 return false;
854 }
855 }
856 catch (...)
857 {
858 return false;
859 }
860
861
862 if (!vfExec.empty())
863 return false;
864
865 return true;
866}
867
868
869
870
871
872
873
874
875
876uint256 SignatureHash(CScript scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType)
877{
878 if (nIn >= txTo.vin.size())
879 {
880 printf("ERROR: SignatureHash() : nIn=%d out of range\n", nIn);
881 return 1;
882 }
883 CTransaction txTmp(txTo);
884
885 // In case concatenating two scripts ends up with two codeseparators,
886 // or an extra one at the end, this prevents all those possible incompatibilities.
887 scriptCode.FindAndDelete(CScript(OP_CODESEPARATOR));
888
889 // Blank out other inputs' signatures
890 for (int i = 0; i < txTmp.vin.size(); i++)
891 txTmp.vin[i].scriptSig = CScript();
892 txTmp.vin[nIn].scriptSig = scriptCode;
893
894 // Blank out some of the outputs
895 if ((nHashType & 0x1f) == SIGHASH_NONE)
896 {
897 // Wildcard payee
898 txTmp.vout.clear();
899
900 // Let the others update at will
901 for (int i = 0; i < txTmp.vin.size(); i++)
902 if (i != nIn)
903 txTmp.vin[i].nSequence = 0;
904 }
905 else if ((nHashType & 0x1f) == SIGHASH_SINGLE)
906 {
907 // Only lockin the txout payee at same index as txin
908 unsigned int nOut = nIn;
909 if (nOut >= txTmp.vout.size())
910 {
911 printf("ERROR: SignatureHash() : nOut=%d out of range\n", nOut);
912 return 1;
913 }
914 txTmp.vout.resize(nOut+1);
915 for (int i = 0; i < nOut; i++)
916 txTmp.vout[i].SetNull();
917
918 // Let the others update at will
919 for (int i = 0; i < txTmp.vin.size(); i++)
920 if (i != nIn)
921 txTmp.vin[i].nSequence = 0;
922 }
923
924 // Blank out other inputs completely, not recommended for open transactions
925 if (nHashType & SIGHASH_ANYONECANPAY)
926 {
927 txTmp.vin[0] = txTmp.vin[nIn];
928 txTmp.vin.resize(1);
929 }
930
931 // Serialize and hash
932 CDataStream ss(SER_GETHASH);
933 ss.reserve(10000);
934 ss << txTmp << nHashType;
935 return Hash(ss.begin(), ss.end());
936}
937
938
939bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode,
940 const CTransaction& txTo, unsigned int nIn, int nHashType)
941{
942 CKey key;
943 if (!key.SetPubKey(vchPubKey))
944 return false;
945
946 // Hash type is one byte tacked on to the end of the signature
947 if (vchSig.empty())
948 return false;
949 if (nHashType == 0)
950 nHashType = vchSig.back();
951 else if (nHashType != vchSig.back())
952 return false;
953 vchSig.pop_back();
954
955 return key.Verify(SignatureHash(scriptCode, txTo, nIn, nHashType), vchSig);
956}
957
958
959
960
961
962
963
964
965
966
967bool Solver(const CScript& scriptPubKey, vector<pair<opcodetype, valtype> >& vSolutionRet)
968{
969 // Templates
970 static vector<CScript> vTemplates;
971 if (vTemplates.empty())
972 {
973 // Standard tx, sender provides pubkey, receiver adds signature
974 vTemplates.push_back(CScript() << OP_PUBKEY << OP_CHECKSIG);
975
976 // Bitcoin address tx, sender provides hash of pubkey, receiver provides signature and pubkey
977 vTemplates.push_back(CScript() << OP_DUP << OP_HASH160 << OP_PUBKEYHASH << OP_EQUALVERIFY << OP_CHECKSIG);
978 }
979
980 // Scan templates
981 const CScript& script1 = scriptPubKey;
982 BOOST_FOREACH(const CScript& script2, vTemplates)
983 {
984 vSolutionRet.clear();
985 opcodetype opcode1, opcode2;
986 vector<unsigned char> vch1, vch2;
987
988 // Compare
989 CScript::const_iterator pc1 = script1.begin();
990 CScript::const_iterator pc2 = script2.begin();
991 loop
992 {
993 if (pc1 == script1.end() && pc2 == script2.end())
994 {
995 // Found a match
996 reverse(vSolutionRet.begin(), vSolutionRet.end());
997 return true;
998 }
999 if (!script1.GetOp(pc1, opcode1, vch1))
1000 break;
1001 if (!script2.GetOp(pc2, opcode2, vch2))
1002 break;
1003 if (opcode2 == OP_PUBKEY)
1004 {
1005 if (vch1.size() < 33 || vch1.size() > 120)
1006 break;
1007 vSolutionRet.push_back(make_pair(opcode2, vch1));
1008 }
1009 else if (opcode2 == OP_PUBKEYHASH)
1010 {
1011 if (vch1.size() != sizeof(uint160))
1012 break;
1013 vSolutionRet.push_back(make_pair(opcode2, vch1));
1014 }
1015 else if (opcode1 != opcode2 || vch1 != vch2)
1016 {
1017 break;
1018 }
1019 }
1020 }
1021
1022 vSolutionRet.clear();
1023 return false;
1024}
1025
1026
1027bool Solver(const CKeyStore& keystore, const CScript& scriptPubKey, uint256 hash, int nHashType, CScript& scriptSigRet)
1028{
1029 scriptSigRet.clear();
1030
1031 vector<pair<opcodetype, valtype> > vSolution;
1032 if (!Solver(scriptPubKey, vSolution))
1033 return false;
1034
1035 // Compile solution
1036 BOOST_FOREACH(PAIRTYPE(opcodetype, valtype)& item, vSolution)
1037 {
1038 if (item.first == OP_PUBKEY)
1039 {
1040 // Sign
1041 const valtype& vchPubKey = item.second;
1042 CKey key;
1043 if (!keystore.GetKey(Hash160(vchPubKey), key))
1044 return false;
1045 if (key.GetPubKey() != vchPubKey)
1046 return false;
1047 if (hash != 0)
1048 {
1049 vector<unsigned char> vchSig;
1050 if (!key.Sign(hash, vchSig))
1051 return false;
1052 vchSig.push_back((unsigned char)nHashType);
1053 scriptSigRet << vchSig;
1054 }
1055 }
1056 else if (item.first == OP_PUBKEYHASH)
1057 {
1058 // Sign and give pubkey
1059 CKey key;
1060 if (!keystore.GetKey(uint160(item.second), key))
1061 return false;
1062 if (hash != 0)
1063 {
1064 vector<unsigned char> vchSig;
1065 if (!key.Sign(hash, vchSig))
1066 return false;
1067 vchSig.push_back((unsigned char)nHashType);
1068 scriptSigRet << vchSig << key.GetPubKey();
1069 }
1070 }
1071 else
1072 {
1073 return false;
1074 }
1075 }
1076
1077 return true;
1078}
1079
1080
1081bool IsStandard(const CScript& scriptPubKey)
1082{
1083 vector<pair<opcodetype, valtype> > vSolution;
1084 return Solver(scriptPubKey, vSolution);
1085}
1086
1087
1088bool IsMine(const CKeyStore &keystore, const CScript& scriptPubKey)
1089{
1090 vector<pair<opcodetype, valtype> > vSolution;
1091 if (!Solver(scriptPubKey, vSolution))
1092 return false;
1093
1094 // Compile solution
1095 BOOST_FOREACH(PAIRTYPE(opcodetype, valtype)& item, vSolution)
1096 {
1097 if (item.first == OP_PUBKEY)
1098 {
1099 const valtype& vchPubKey = item.second;
1100 vector<unsigned char> vchPubKeyFound;
1101 if (!keystore.GetPubKey(Hash160(vchPubKey), vchPubKeyFound))
1102 return false;
1103 if (vchPubKeyFound != vchPubKey)
1104 return false;
1105 }
1106 else if (item.first == OP_PUBKEYHASH)
1107 {
1108 if (!keystore.HaveKey(uint160(item.second)))
1109 return false;
1110 }
1111 else
1112 {
1113 return false;
1114 }
1115 }
1116
1117 return true;
1118}
1119
1120bool static ExtractAddressInner(const CScript& scriptPubKey, const CKeyStore* keystore, CBitcoinAddress& addressRet)
1121{
1122 vector<pair<opcodetype, valtype> > vSolution;
1123 if (!Solver(scriptPubKey, vSolution))
1124 return false;
1125
1126 BOOST_FOREACH(PAIRTYPE(opcodetype, valtype)& item, vSolution)
1127 {
1128 if (item.first == OP_PUBKEY)
1129 addressRet.SetPubKey(item.second);
1130 else if (item.first == OP_PUBKEYHASH)
1131 addressRet.SetHash160((uint160)item.second);
1132 if (keystore == NULL || keystore->HaveKey(addressRet))
1133 return true;
1134 }
1135
1136 return false;
1137}
1138
1139
1140bool ExtractAddress(const CScript& scriptPubKey, const CKeyStore* keystore, CBitcoinAddress& addressRet)
1141{
1142 if (keystore)
1143 return ExtractAddressInner(scriptPubKey, keystore, addressRet);
1144 else
1145 return ExtractAddressInner(scriptPubKey, NULL, addressRet);
1146 return false;
1147}
1148
1149
1150bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, int nHashType)
1151{
1152 vector<vector<unsigned char> > stack;
1153 if (!EvalScript(stack, scriptSig, txTo, nIn, nHashType))
1154 return false;
1155 if (!EvalScript(stack, scriptPubKey, txTo, nIn, nHashType))
1156 return false;
1157 if (stack.empty())
1158 return false;
1159 return CastToBool(stack.back());
1160}
1161
1162
1163bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType, CScript scriptPrereq)
1164{
1165 assert(nIn < txTo.vin.size());
1166 CTxIn& txin = txTo.vin[nIn];
1167 assert(txin.prevout.n < txFrom.vout.size());
1168 const CTxOut& txout = txFrom.vout[txin.prevout.n];
1169
1170 // Leave out the signature from the hash, since a signature can't sign itself.
1171 // The checksig op will also drop the signatures from its hash.
1172 uint256 hash = SignatureHash(scriptPrereq + txout.scriptPubKey, txTo, nIn, nHashType);
1173
1174 if (!Solver(keystore, txout.scriptPubKey, hash, nHashType, txin.scriptSig))
1175 return false;
1176
1177 txin.scriptSig = scriptPrereq + txin.scriptSig;
1178
1179 // Test solution
1180 if (scriptPrereq.empty())
1181 if (!VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, 0))
1182 return false;
1183
1184 return true;
1185}
1186
1187
1188bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, int nHashType)
1189{
1190 assert(nIn < txTo.vin.size());
1191 const CTxIn& txin = txTo.vin[nIn];
1192 if (txin.prevout.n >= txFrom.vout.size())
1193 return false;
1194 const CTxOut& txout = txFrom.vout[txin.prevout.n];
1195
1196 if (txin.prevout.hash != txFrom.GetHash())
1197 return false;
1198
1199 if (!VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, nHashType))
1200 return false;
1201
1202 return true;
1203}