forked from decred/dcrd
-
Notifications
You must be signed in to change notification settings - Fork 0
/
opcode.go
2983 lines (2689 loc) · 102 KB
/
opcode.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// Copyright (c) 2013-2016 The btcsuite developers
// Copyright (c) 2015-2023 The Decred developers
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package txscript
import (
"bytes"
"crypto/sha1"
"crypto/sha256"
"encoding/hex"
"fmt"
"hash"
"strings"
"github.com/decred/dcrd/chaincfg/chainhash"
"github.com/decred/dcrd/crypto/ripemd160"
"github.com/decred/dcrd/dcrec"
"github.com/decred/dcrd/dcrec/edwards/v2"
"github.com/decred/dcrd/dcrec/secp256k1/v4"
"github.com/decred/dcrd/dcrec/secp256k1/v4/ecdsa"
"github.com/decred/dcrd/dcrec/secp256k1/v4/schnorr"
"github.com/decred/dcrd/wire"
)
// optimizeSigVerification is an optimization for verification of transactions
// that contain scripts with CHECKSIG operations with a hash type of SigHashAll.
//
// WARNING: This has not been properly vetted or tested, so it needs significant
// review to ensure it does not break consensus before being enabled.
const optimizeSigVerification = false
// An opcode defines the information related to a txscript opcode. opfunc, if
// present, is the function to call to perform the opcode on the script. The
// current script is passed in as a slice with the first member being the opcode
// itself.
type opcode struct {
value byte
name string
length int
opfunc func(*opcode, []byte, *Engine) error
}
// These constants are the values of the official opcodes used on the btc wiki,
// in bitcoin core and in most if not all other references and software related
// to handling DCR scripts.
const (
OP_0 = 0x00 // 0
OP_FALSE = 0x00 // 0 - AKA OP_0
OP_DATA_1 = 0x01 // 1
OP_DATA_2 = 0x02 // 2
OP_DATA_3 = 0x03 // 3
OP_DATA_4 = 0x04 // 4
OP_DATA_5 = 0x05 // 5
OP_DATA_6 = 0x06 // 6
OP_DATA_7 = 0x07 // 7
OP_DATA_8 = 0x08 // 8
OP_DATA_9 = 0x09 // 9
OP_DATA_10 = 0x0a // 10
OP_DATA_11 = 0x0b // 11
OP_DATA_12 = 0x0c // 12
OP_DATA_13 = 0x0d // 13
OP_DATA_14 = 0x0e // 14
OP_DATA_15 = 0x0f // 15
OP_DATA_16 = 0x10 // 16
OP_DATA_17 = 0x11 // 17
OP_DATA_18 = 0x12 // 18
OP_DATA_19 = 0x13 // 19
OP_DATA_20 = 0x14 // 20
OP_DATA_21 = 0x15 // 21
OP_DATA_22 = 0x16 // 22
OP_DATA_23 = 0x17 // 23
OP_DATA_24 = 0x18 // 24
OP_DATA_25 = 0x19 // 25
OP_DATA_26 = 0x1a // 26
OP_DATA_27 = 0x1b // 27
OP_DATA_28 = 0x1c // 28
OP_DATA_29 = 0x1d // 29
OP_DATA_30 = 0x1e // 30
OP_DATA_31 = 0x1f // 31
OP_DATA_32 = 0x20 // 32
OP_DATA_33 = 0x21 // 33
OP_DATA_34 = 0x22 // 34
OP_DATA_35 = 0x23 // 35
OP_DATA_36 = 0x24 // 36
OP_DATA_37 = 0x25 // 37
OP_DATA_38 = 0x26 // 38
OP_DATA_39 = 0x27 // 39
OP_DATA_40 = 0x28 // 40
OP_DATA_41 = 0x29 // 41
OP_DATA_42 = 0x2a // 42
OP_DATA_43 = 0x2b // 43
OP_DATA_44 = 0x2c // 44
OP_DATA_45 = 0x2d // 45
OP_DATA_46 = 0x2e // 46
OP_DATA_47 = 0x2f // 47
OP_DATA_48 = 0x30 // 48
OP_DATA_49 = 0x31 // 49
OP_DATA_50 = 0x32 // 50
OP_DATA_51 = 0x33 // 51
OP_DATA_52 = 0x34 // 52
OP_DATA_53 = 0x35 // 53
OP_DATA_54 = 0x36 // 54
OP_DATA_55 = 0x37 // 55
OP_DATA_56 = 0x38 // 56
OP_DATA_57 = 0x39 // 57
OP_DATA_58 = 0x3a // 58
OP_DATA_59 = 0x3b // 59
OP_DATA_60 = 0x3c // 60
OP_DATA_61 = 0x3d // 61
OP_DATA_62 = 0x3e // 62
OP_DATA_63 = 0x3f // 63
OP_DATA_64 = 0x40 // 64
OP_DATA_65 = 0x41 // 65
OP_DATA_66 = 0x42 // 66
OP_DATA_67 = 0x43 // 67
OP_DATA_68 = 0x44 // 68
OP_DATA_69 = 0x45 // 69
OP_DATA_70 = 0x46 // 70
OP_DATA_71 = 0x47 // 71
OP_DATA_72 = 0x48 // 72
OP_DATA_73 = 0x49 // 73
OP_DATA_74 = 0x4a // 74
OP_DATA_75 = 0x4b // 75
OP_PUSHDATA1 = 0x4c // 76
OP_PUSHDATA2 = 0x4d // 77
OP_PUSHDATA4 = 0x4e // 78
OP_1NEGATE = 0x4f // 79
OP_RESERVED = 0x50 // 80
OP_1 = 0x51 // 81 - AKA OP_TRUE
OP_TRUE = 0x51 // 81
OP_2 = 0x52 // 82
OP_3 = 0x53 // 83
OP_4 = 0x54 // 84
OP_5 = 0x55 // 85
OP_6 = 0x56 // 86
OP_7 = 0x57 // 87
OP_8 = 0x58 // 88
OP_9 = 0x59 // 89
OP_10 = 0x5a // 90
OP_11 = 0x5b // 91
OP_12 = 0x5c // 92
OP_13 = 0x5d // 93
OP_14 = 0x5e // 94
OP_15 = 0x5f // 95
OP_16 = 0x60 // 96
OP_NOP = 0x61 // 97
OP_VER = 0x62 // 98
OP_IF = 0x63 // 99
OP_NOTIF = 0x64 // 100
OP_VERIF = 0x65 // 101
OP_VERNOTIF = 0x66 // 102
OP_ELSE = 0x67 // 103
OP_ENDIF = 0x68 // 104
OP_VERIFY = 0x69 // 105
OP_RETURN = 0x6a // 106
OP_TOALTSTACK = 0x6b // 107
OP_FROMALTSTACK = 0x6c // 108
OP_2DROP = 0x6d // 109
OP_2DUP = 0x6e // 110
OP_3DUP = 0x6f // 111
OP_2OVER = 0x70 // 112
OP_2ROT = 0x71 // 113
OP_2SWAP = 0x72 // 114
OP_IFDUP = 0x73 // 115
OP_DEPTH = 0x74 // 116
OP_DROP = 0x75 // 117
OP_DUP = 0x76 // 118
OP_NIP = 0x77 // 119
OP_OVER = 0x78 // 120
OP_PICK = 0x79 // 121
OP_ROLL = 0x7a // 122
OP_ROT = 0x7b // 123
OP_SWAP = 0x7c // 124
OP_TUCK = 0x7d // 125
OP_CAT = 0x7e // 126
OP_SUBSTR = 0x7f // 127
OP_LEFT = 0x80 // 128
OP_RIGHT = 0x81 // 129
OP_SIZE = 0x82 // 130
OP_INVERT = 0x83 // 131
OP_AND = 0x84 // 132
OP_OR = 0x85 // 133
OP_XOR = 0x86 // 134
OP_EQUAL = 0x87 // 135
OP_EQUALVERIFY = 0x88 // 136
OP_ROTR = 0x89 // 137
OP_ROTL = 0x8a // 138
OP_1ADD = 0x8b // 139
OP_1SUB = 0x8c // 140
OP_2MUL = 0x8d // 141
OP_2DIV = 0x8e // 142
OP_NEGATE = 0x8f // 143
OP_ABS = 0x90 // 144
OP_NOT = 0x91 // 145
OP_0NOTEQUAL = 0x92 // 146
OP_ADD = 0x93 // 147
OP_SUB = 0x94 // 148
OP_MUL = 0x95 // 149
OP_DIV = 0x96 // 150
OP_MOD = 0x97 // 151
OP_LSHIFT = 0x98 // 152
OP_RSHIFT = 0x99 // 153
OP_BOOLAND = 0x9a // 154
OP_BOOLOR = 0x9b // 155
OP_NUMEQUAL = 0x9c // 156
OP_NUMEQUALVERIFY = 0x9d // 157
OP_NUMNOTEQUAL = 0x9e // 158
OP_LESSTHAN = 0x9f // 159
OP_GREATERTHAN = 0xa0 // 160
OP_LESSTHANOREQUAL = 0xa1 // 161
OP_GREATERTHANOREQUAL = 0xa2 // 162
OP_MIN = 0xa3 // 163
OP_MAX = 0xa4 // 164
OP_WITHIN = 0xa5 // 165
OP_RIPEMD160 = 0xa6 // 166
OP_SHA1 = 0xa7 // 167
OP_BLAKE256 = 0xa8 // 168
OP_HASH160 = 0xa9 // 169
OP_HASH256 = 0xaa // 170
OP_CODESEPARATOR = 0xab // 171
OP_CHECKSIG = 0xac // 172
OP_CHECKSIGVERIFY = 0xad // 173
OP_CHECKMULTISIG = 0xae // 174
OP_CHECKMULTISIGVERIFY = 0xaf // 175
OP_NOP1 = 0xb0 // 176
OP_NOP2 = 0xb1 // 177
OP_CHECKLOCKTIMEVERIFY = 0xb1 // 177 - AKA OP_NOP2
OP_NOP3 = 0xb2 // 178
OP_CHECKSEQUENCEVERIFY = 0xb2 // 178 - AKA OP_NOP3
OP_NOP4 = 0xb3 // 179
OP_NOP5 = 0xb4 // 180
OP_NOP6 = 0xb5 // 181
OP_NOP7 = 0xb6 // 182
OP_NOP8 = 0xb7 // 183
OP_NOP9 = 0xb8 // 184
OP_NOP10 = 0xb9 // 185
OP_SSTX = 0xba // 186 DECRED
OP_SSGEN = 0xbb // 187 DECRED
OP_SSRTX = 0xbc // 188 DECRED
OP_SSTXCHANGE = 0xbd // 189 DECRED
OP_CHECKSIGALT = 0xbe // 190 DECRED
OP_CHECKSIGALTVERIFY = 0xbf // 191 DECRED
OP_SHA256 = 0xc0 // 192
OP_TADD = 0xc1 // 193 DECRED
OP_TSPEND = 0xc2 // 194 DECRED
OP_TGEN = 0xc3 // 195 DECRED
OP_UNKNOWN196 = 0xc4 // 196
OP_UNKNOWN197 = 0xc5 // 197
OP_UNKNOWN198 = 0xc6 // 198
OP_UNKNOWN199 = 0xc7 // 199
OP_UNKNOWN200 = 0xc8 // 200
OP_UNKNOWN201 = 0xc9 // 201
OP_UNKNOWN202 = 0xca // 202
OP_UNKNOWN203 = 0xcb // 203
OP_UNKNOWN204 = 0xcc // 204
OP_UNKNOWN205 = 0xcd // 205
OP_UNKNOWN206 = 0xce // 206
OP_UNKNOWN207 = 0xcf // 207
OP_UNKNOWN208 = 0xd0 // 208
OP_UNKNOWN209 = 0xd1 // 209
OP_UNKNOWN210 = 0xd2 // 210
OP_UNKNOWN211 = 0xd3 // 211
OP_UNKNOWN212 = 0xd4 // 212
OP_UNKNOWN213 = 0xd5 // 213
OP_UNKNOWN214 = 0xd6 // 214
OP_UNKNOWN215 = 0xd7 // 215
OP_UNKNOWN216 = 0xd8 // 216
OP_UNKNOWN217 = 0xd9 // 217
OP_UNKNOWN218 = 0xda // 218
OP_UNKNOWN219 = 0xdb // 219
OP_UNKNOWN220 = 0xdc // 220
OP_UNKNOWN221 = 0xdd // 221
OP_UNKNOWN222 = 0xde // 222
OP_UNKNOWN223 = 0xdf // 223
OP_UNKNOWN224 = 0xe0 // 224
OP_UNKNOWN225 = 0xe1 // 225
OP_UNKNOWN226 = 0xe2 // 226
OP_UNKNOWN227 = 0xe3 // 227
OP_UNKNOWN228 = 0xe4 // 228
OP_UNKNOWN229 = 0xe5 // 229
OP_UNKNOWN230 = 0xe6 // 230
OP_UNKNOWN231 = 0xe7 // 231
OP_UNKNOWN232 = 0xe8 // 232
OP_UNKNOWN233 = 0xe9 // 233
OP_UNKNOWN234 = 0xea // 234
OP_UNKNOWN235 = 0xeb // 235
OP_UNKNOWN236 = 0xec // 236
OP_UNKNOWN237 = 0xed // 237
OP_UNKNOWN238 = 0xee // 238
OP_UNKNOWN239 = 0xef // 239
OP_UNKNOWN240 = 0xf0 // 240
OP_UNKNOWN241 = 0xf1 // 241
OP_UNKNOWN242 = 0xf2 // 242
OP_UNKNOWN243 = 0xf3 // 243
OP_UNKNOWN244 = 0xf4 // 244
OP_UNKNOWN245 = 0xf5 // 245
OP_UNKNOWN246 = 0xf6 // 246
OP_UNKNOWN247 = 0xf7 // 247
OP_UNKNOWN248 = 0xf8 // 248
OP_INVALID249 = 0xf9 // 249 - bitcoin core internal
OP_SMALLINTEGER = 0xfa // 250 - bitcoin core internal
OP_PUBKEYS = 0xfb // 251 - bitcoin core internal
OP_UNKNOWN252 = 0xfc // 252
OP_PUBKEYHASH = 0xfd // 253 - bitcoin core internal
OP_PUBKEY = 0xfe // 254 - bitcoin core internal
OP_INVALIDOPCODE = 0xff // 255 - bitcoin core internal
)
// opcodeArray holds details about all possible opcodes such as how many bytes
// the opcode and any associated data should take, its human-readable name, and
// the handler function.
var opcodeArray = [256]opcode{
// Data push opcodes.
OP_FALSE: {OP_FALSE, "OP_0", 1, opcodeFalse},
OP_DATA_1: {OP_DATA_1, "OP_DATA_1", 2, opcodePushData},
OP_DATA_2: {OP_DATA_2, "OP_DATA_2", 3, opcodePushData},
OP_DATA_3: {OP_DATA_3, "OP_DATA_3", 4, opcodePushData},
OP_DATA_4: {OP_DATA_4, "OP_DATA_4", 5, opcodePushData},
OP_DATA_5: {OP_DATA_5, "OP_DATA_5", 6, opcodePushData},
OP_DATA_6: {OP_DATA_6, "OP_DATA_6", 7, opcodePushData},
OP_DATA_7: {OP_DATA_7, "OP_DATA_7", 8, opcodePushData},
OP_DATA_8: {OP_DATA_8, "OP_DATA_8", 9, opcodePushData},
OP_DATA_9: {OP_DATA_9, "OP_DATA_9", 10, opcodePushData},
OP_DATA_10: {OP_DATA_10, "OP_DATA_10", 11, opcodePushData},
OP_DATA_11: {OP_DATA_11, "OP_DATA_11", 12, opcodePushData},
OP_DATA_12: {OP_DATA_12, "OP_DATA_12", 13, opcodePushData},
OP_DATA_13: {OP_DATA_13, "OP_DATA_13", 14, opcodePushData},
OP_DATA_14: {OP_DATA_14, "OP_DATA_14", 15, opcodePushData},
OP_DATA_15: {OP_DATA_15, "OP_DATA_15", 16, opcodePushData},
OP_DATA_16: {OP_DATA_16, "OP_DATA_16", 17, opcodePushData},
OP_DATA_17: {OP_DATA_17, "OP_DATA_17", 18, opcodePushData},
OP_DATA_18: {OP_DATA_18, "OP_DATA_18", 19, opcodePushData},
OP_DATA_19: {OP_DATA_19, "OP_DATA_19", 20, opcodePushData},
OP_DATA_20: {OP_DATA_20, "OP_DATA_20", 21, opcodePushData},
OP_DATA_21: {OP_DATA_21, "OP_DATA_21", 22, opcodePushData},
OP_DATA_22: {OP_DATA_22, "OP_DATA_22", 23, opcodePushData},
OP_DATA_23: {OP_DATA_23, "OP_DATA_23", 24, opcodePushData},
OP_DATA_24: {OP_DATA_24, "OP_DATA_24", 25, opcodePushData},
OP_DATA_25: {OP_DATA_25, "OP_DATA_25", 26, opcodePushData},
OP_DATA_26: {OP_DATA_26, "OP_DATA_26", 27, opcodePushData},
OP_DATA_27: {OP_DATA_27, "OP_DATA_27", 28, opcodePushData},
OP_DATA_28: {OP_DATA_28, "OP_DATA_28", 29, opcodePushData},
OP_DATA_29: {OP_DATA_29, "OP_DATA_29", 30, opcodePushData},
OP_DATA_30: {OP_DATA_30, "OP_DATA_30", 31, opcodePushData},
OP_DATA_31: {OP_DATA_31, "OP_DATA_31", 32, opcodePushData},
OP_DATA_32: {OP_DATA_32, "OP_DATA_32", 33, opcodePushData},
OP_DATA_33: {OP_DATA_33, "OP_DATA_33", 34, opcodePushData},
OP_DATA_34: {OP_DATA_34, "OP_DATA_34", 35, opcodePushData},
OP_DATA_35: {OP_DATA_35, "OP_DATA_35", 36, opcodePushData},
OP_DATA_36: {OP_DATA_36, "OP_DATA_36", 37, opcodePushData},
OP_DATA_37: {OP_DATA_37, "OP_DATA_37", 38, opcodePushData},
OP_DATA_38: {OP_DATA_38, "OP_DATA_38", 39, opcodePushData},
OP_DATA_39: {OP_DATA_39, "OP_DATA_39", 40, opcodePushData},
OP_DATA_40: {OP_DATA_40, "OP_DATA_40", 41, opcodePushData},
OP_DATA_41: {OP_DATA_41, "OP_DATA_41", 42, opcodePushData},
OP_DATA_42: {OP_DATA_42, "OP_DATA_42", 43, opcodePushData},
OP_DATA_43: {OP_DATA_43, "OP_DATA_43", 44, opcodePushData},
OP_DATA_44: {OP_DATA_44, "OP_DATA_44", 45, opcodePushData},
OP_DATA_45: {OP_DATA_45, "OP_DATA_45", 46, opcodePushData},
OP_DATA_46: {OP_DATA_46, "OP_DATA_46", 47, opcodePushData},
OP_DATA_47: {OP_DATA_47, "OP_DATA_47", 48, opcodePushData},
OP_DATA_48: {OP_DATA_48, "OP_DATA_48", 49, opcodePushData},
OP_DATA_49: {OP_DATA_49, "OP_DATA_49", 50, opcodePushData},
OP_DATA_50: {OP_DATA_50, "OP_DATA_50", 51, opcodePushData},
OP_DATA_51: {OP_DATA_51, "OP_DATA_51", 52, opcodePushData},
OP_DATA_52: {OP_DATA_52, "OP_DATA_52", 53, opcodePushData},
OP_DATA_53: {OP_DATA_53, "OP_DATA_53", 54, opcodePushData},
OP_DATA_54: {OP_DATA_54, "OP_DATA_54", 55, opcodePushData},
OP_DATA_55: {OP_DATA_55, "OP_DATA_55", 56, opcodePushData},
OP_DATA_56: {OP_DATA_56, "OP_DATA_56", 57, opcodePushData},
OP_DATA_57: {OP_DATA_57, "OP_DATA_57", 58, opcodePushData},
OP_DATA_58: {OP_DATA_58, "OP_DATA_58", 59, opcodePushData},
OP_DATA_59: {OP_DATA_59, "OP_DATA_59", 60, opcodePushData},
OP_DATA_60: {OP_DATA_60, "OP_DATA_60", 61, opcodePushData},
OP_DATA_61: {OP_DATA_61, "OP_DATA_61", 62, opcodePushData},
OP_DATA_62: {OP_DATA_62, "OP_DATA_62", 63, opcodePushData},
OP_DATA_63: {OP_DATA_63, "OP_DATA_63", 64, opcodePushData},
OP_DATA_64: {OP_DATA_64, "OP_DATA_64", 65, opcodePushData},
OP_DATA_65: {OP_DATA_65, "OP_DATA_65", 66, opcodePushData},
OP_DATA_66: {OP_DATA_66, "OP_DATA_66", 67, opcodePushData},
OP_DATA_67: {OP_DATA_67, "OP_DATA_67", 68, opcodePushData},
OP_DATA_68: {OP_DATA_68, "OP_DATA_68", 69, opcodePushData},
OP_DATA_69: {OP_DATA_69, "OP_DATA_69", 70, opcodePushData},
OP_DATA_70: {OP_DATA_70, "OP_DATA_70", 71, opcodePushData},
OP_DATA_71: {OP_DATA_71, "OP_DATA_71", 72, opcodePushData},
OP_DATA_72: {OP_DATA_72, "OP_DATA_72", 73, opcodePushData},
OP_DATA_73: {OP_DATA_73, "OP_DATA_73", 74, opcodePushData},
OP_DATA_74: {OP_DATA_74, "OP_DATA_74", 75, opcodePushData},
OP_DATA_75: {OP_DATA_75, "OP_DATA_75", 76, opcodePushData},
OP_PUSHDATA1: {OP_PUSHDATA1, "OP_PUSHDATA1", -1, opcodePushData},
OP_PUSHDATA2: {OP_PUSHDATA2, "OP_PUSHDATA2", -2, opcodePushData},
OP_PUSHDATA4: {OP_PUSHDATA4, "OP_PUSHDATA4", -4, opcodePushData},
OP_1NEGATE: {OP_1NEGATE, "OP_1NEGATE", 1, opcode1Negate},
OP_RESERVED: {OP_RESERVED, "OP_RESERVED", 1, opcodeReserved},
OP_TRUE: {OP_TRUE, "OP_1", 1, opcodeN},
OP_2: {OP_2, "OP_2", 1, opcodeN},
OP_3: {OP_3, "OP_3", 1, opcodeN},
OP_4: {OP_4, "OP_4", 1, opcodeN},
OP_5: {OP_5, "OP_5", 1, opcodeN},
OP_6: {OP_6, "OP_6", 1, opcodeN},
OP_7: {OP_7, "OP_7", 1, opcodeN},
OP_8: {OP_8, "OP_8", 1, opcodeN},
OP_9: {OP_9, "OP_9", 1, opcodeN},
OP_10: {OP_10, "OP_10", 1, opcodeN},
OP_11: {OP_11, "OP_11", 1, opcodeN},
OP_12: {OP_12, "OP_12", 1, opcodeN},
OP_13: {OP_13, "OP_13", 1, opcodeN},
OP_14: {OP_14, "OP_14", 1, opcodeN},
OP_15: {OP_15, "OP_15", 1, opcodeN},
OP_16: {OP_16, "OP_16", 1, opcodeN},
// Control opcodes.
OP_NOP: {OP_NOP, "OP_NOP", 1, opcodeNop},
OP_VER: {OP_VER, "OP_VER", 1, opcodeReserved},
OP_IF: {OP_IF, "OP_IF", 1, opcodeIf},
OP_NOTIF: {OP_NOTIF, "OP_NOTIF", 1, opcodeNotIf},
OP_VERIF: {OP_VERIF, "OP_VERIF", 1, opcodeReserved},
OP_VERNOTIF: {OP_VERNOTIF, "OP_VERNOTIF", 1, opcodeReserved},
OP_ELSE: {OP_ELSE, "OP_ELSE", 1, opcodeElse},
OP_ENDIF: {OP_ENDIF, "OP_ENDIF", 1, opcodeEndif},
OP_VERIFY: {OP_VERIFY, "OP_VERIFY", 1, opcodeVerify},
OP_RETURN: {OP_RETURN, "OP_RETURN", 1, opcodeReturn},
OP_CHECKLOCKTIMEVERIFY: {OP_CHECKLOCKTIMEVERIFY, "OP_CHECKLOCKTIMEVERIFY", 1, opcodeCheckLockTimeVerify},
OP_CHECKSEQUENCEVERIFY: {OP_CHECKSEQUENCEVERIFY, "OP_CHECKSEQUENCEVERIFY", 1, opcodeCheckSequenceVerify},
// Stack opcodes.
OP_TOALTSTACK: {OP_TOALTSTACK, "OP_TOALTSTACK", 1, opcodeToAltStack},
OP_FROMALTSTACK: {OP_FROMALTSTACK, "OP_FROMALTSTACK", 1, opcodeFromAltStack},
OP_2DROP: {OP_2DROP, "OP_2DROP", 1, opcode2Drop},
OP_2DUP: {OP_2DUP, "OP_2DUP", 1, opcode2Dup},
OP_3DUP: {OP_3DUP, "OP_3DUP", 1, opcode3Dup},
OP_2OVER: {OP_2OVER, "OP_2OVER", 1, opcode2Over},
OP_2ROT: {OP_2ROT, "OP_2ROT", 1, opcode2Rot},
OP_2SWAP: {OP_2SWAP, "OP_2SWAP", 1, opcode2Swap},
OP_IFDUP: {OP_IFDUP, "OP_IFDUP", 1, opcodeIfDup},
OP_DEPTH: {OP_DEPTH, "OP_DEPTH", 1, opcodeDepth},
OP_DROP: {OP_DROP, "OP_DROP", 1, opcodeDrop},
OP_DUP: {OP_DUP, "OP_DUP", 1, opcodeDup},
OP_NIP: {OP_NIP, "OP_NIP", 1, opcodeNip},
OP_OVER: {OP_OVER, "OP_OVER", 1, opcodeOver},
OP_PICK: {OP_PICK, "OP_PICK", 1, opcodePick},
OP_ROLL: {OP_ROLL, "OP_ROLL", 1, opcodeRoll},
OP_ROT: {OP_ROT, "OP_ROT", 1, opcodeRot},
OP_SWAP: {OP_SWAP, "OP_SWAP", 1, opcodeSwap},
OP_TUCK: {OP_TUCK, "OP_TUCK", 1, opcodeTuck},
// Splice opcodes.
OP_CAT: {OP_CAT, "OP_CAT", 1, opcodeCat},
OP_SUBSTR: {OP_SUBSTR, "OP_SUBSTR", 1, opcodeSubstr},
OP_LEFT: {OP_LEFT, "OP_LEFT", 1, opcodeLeft},
OP_RIGHT: {OP_RIGHT, "OP_RIGHT", 1, opcodeRight},
OP_SIZE: {OP_SIZE, "OP_SIZE", 1, opcodeSize},
// Bitwise logic opcodes for int32 registers derived from the stack.
OP_INVERT: {OP_INVERT, "OP_INVERT", 1, opcodeInvert},
OP_AND: {OP_AND, "OP_AND", 1, opcodeAnd},
OP_OR: {OP_OR, "OP_OR", 1, opcodeOr},
OP_XOR: {OP_XOR, "OP_XOR", 1, opcodeXor},
// Bytewise comparison function opcodes for byte strings.
OP_EQUAL: {OP_EQUAL, "OP_EQUAL", 1, opcodeEqual},
OP_EQUALVERIFY: {OP_EQUALVERIFY, "OP_EQUALVERIFY", 1, opcodeEqualVerify},
// Bitwise rotation opcodes for an int32 register derived from the stack.
OP_ROTR: {OP_ROTR, "OP_ROTR", 1, opcodeRotr},
OP_ROTL: {OP_ROTL, "OP_ROTL", 1, opcodeRotl},
// Numeric related opcodes.
OP_1ADD: {OP_1ADD, "OP_1ADD", 1, opcode1Add},
OP_1SUB: {OP_1SUB, "OP_1SUB", 1, opcode1Sub},
OP_2MUL: {OP_2MUL, "OP_2MUL", 1, opcodeNop},
OP_2DIV: {OP_2DIV, "OP_2DIV", 1, opcodeNop},
OP_NEGATE: {OP_NEGATE, "OP_NEGATE", 1, opcodeNegate},
OP_ABS: {OP_ABS, "OP_ABS", 1, opcodeAbs},
OP_NOT: {OP_NOT, "OP_NOT", 1, opcodeNot},
OP_0NOTEQUAL: {OP_0NOTEQUAL, "OP_0NOTEQUAL", 1, opcode0NotEqual},
OP_ADD: {OP_ADD, "OP_ADD", 1, opcodeAdd},
OP_SUB: {OP_SUB, "OP_SUB", 1, opcodeSub},
OP_MUL: {OP_MUL, "OP_MUL", 1, opcodeMul},
OP_DIV: {OP_DIV, "OP_DIV", 1, opcodeDiv},
OP_MOD: {OP_MOD, "OP_MOD", 1, opcodeMod},
OP_LSHIFT: {OP_LSHIFT, "OP_LSHIFT", 1, opcodeLShift},
OP_RSHIFT: {OP_RSHIFT, "OP_RSHIFT", 1, opcodeRShift},
OP_BOOLAND: {OP_BOOLAND, "OP_BOOLAND", 1, opcodeBoolAnd},
OP_BOOLOR: {OP_BOOLOR, "OP_BOOLOR", 1, opcodeBoolOr},
OP_NUMEQUAL: {OP_NUMEQUAL, "OP_NUMEQUAL", 1, opcodeNumEqual},
OP_NUMEQUALVERIFY: {OP_NUMEQUALVERIFY, "OP_NUMEQUALVERIFY", 1, opcodeNumEqualVerify},
OP_NUMNOTEQUAL: {OP_NUMNOTEQUAL, "OP_NUMNOTEQUAL", 1, opcodeNumNotEqual},
OP_LESSTHAN: {OP_LESSTHAN, "OP_LESSTHAN", 1, opcodeLessThan},
OP_GREATERTHAN: {OP_GREATERTHAN, "OP_GREATERTHAN", 1, opcodeGreaterThan},
OP_LESSTHANOREQUAL: {OP_LESSTHANOREQUAL, "OP_LESSTHANOREQUAL", 1, opcodeLessThanOrEqual},
OP_GREATERTHANOREQUAL: {OP_GREATERTHANOREQUAL, "OP_GREATERTHANOREQUAL", 1, opcodeGreaterThanOrEqual},
OP_MIN: {OP_MIN, "OP_MIN", 1, opcodeMin},
OP_MAX: {OP_MAX, "OP_MAX", 1, opcodeMax},
OP_WITHIN: {OP_WITHIN, "OP_WITHIN", 1, opcodeWithin},
// Crypto opcodes.
OP_RIPEMD160: {OP_RIPEMD160, "OP_RIPEMD160", 1, opcodeRipemd160},
OP_SHA1: {OP_SHA1, "OP_SHA1", 1, opcodeSha1},
OP_SHA256: {OP_SHA256, "OP_SHA256", 1, opcodeSha256},
OP_BLAKE256: {OP_BLAKE256, "OP_BLAKE256", 1, opcodeBlake256},
OP_HASH160: {OP_HASH160, "OP_HASH160", 1, opcodeHash160},
OP_HASH256: {OP_HASH256, "OP_HASH256", 1, opcodeHash256},
OP_CODESEPARATOR: {OP_CODESEPARATOR, "OP_CODESEPARATOR", 1, opcodeDisabled}, // Disabled
OP_CHECKSIG: {OP_CHECKSIG, "OP_CHECKSIG", 1, opcodeCheckSig},
OP_CHECKSIGVERIFY: {OP_CHECKSIGVERIFY, "OP_CHECKSIGVERIFY", 1, opcodeCheckSigVerify},
OP_CHECKMULTISIG: {OP_CHECKMULTISIG, "OP_CHECKMULTISIG", 1, opcodeCheckMultiSig},
OP_CHECKMULTISIGVERIFY: {OP_CHECKMULTISIGVERIFY, "OP_CHECKMULTISIGVERIFY", 1, opcodeCheckMultiSigVerify},
// Reserved opcodes.
OP_NOP1: {OP_NOP1, "OP_NOP1", 1, opcodeNop},
OP_NOP4: {OP_NOP4, "OP_NOP4", 1, opcodeNop},
OP_NOP5: {OP_NOP5, "OP_NOP5", 1, opcodeNop},
OP_NOP6: {OP_NOP6, "OP_NOP6", 1, opcodeNop},
OP_NOP7: {OP_NOP7, "OP_NOP7", 1, opcodeNop},
OP_NOP8: {OP_NOP8, "OP_NOP8", 1, opcodeNop},
OP_NOP9: {OP_NOP9, "OP_NOP9", 1, opcodeNop},
OP_NOP10: {OP_NOP10, "OP_NOP10", 1, opcodeNop},
// SS* opcodes.
OP_SSTX: {OP_SSTX, "OP_SSTX", 1, opcodeNop},
OP_SSGEN: {OP_SSGEN, "OP_SSGEN", 1, opcodeNop},
OP_SSRTX: {OP_SSRTX, "OP_SSRTX", 1, opcodeNop},
OP_SSTXCHANGE: {OP_SSTXCHANGE, "OP_SSTXCHANGE", 1, opcodeNop},
// Alternative checksig opcode.
OP_CHECKSIGALT: {OP_CHECKSIGALT, "OP_CHECKSIGALT", 1, opcodeCheckSigAlt},
OP_CHECKSIGALTVERIFY: {OP_CHECKSIGALTVERIFY, "OP_CHECKSIGALTVERIFY", 1, opcodeCheckSigAltVerify},
// treasury opcodes.
OP_TADD: {OP_TADD, "OP_TADD", 1, opcodeTAdd},
OP_TSPEND: {OP_TSPEND, "OP_TSPEND", 1, opcodeTSpend},
OP_TGEN: {OP_TGEN, "OP_TGEN", 1, opcodeTGen},
// Undefined opcodes.
OP_UNKNOWN196: {OP_UNKNOWN196, "OP_UNKNOWN196", 1, opcodeNop},
OP_UNKNOWN197: {OP_UNKNOWN197, "OP_UNKNOWN197", 1, opcodeNop},
OP_UNKNOWN198: {OP_UNKNOWN198, "OP_UNKNOWN198", 1, opcodeNop},
OP_UNKNOWN199: {OP_UNKNOWN199, "OP_UNKNOWN199", 1, opcodeNop},
OP_UNKNOWN200: {OP_UNKNOWN200, "OP_UNKNOWN200", 1, opcodeNop},
OP_UNKNOWN201: {OP_UNKNOWN201, "OP_UNKNOWN201", 1, opcodeNop},
OP_UNKNOWN202: {OP_UNKNOWN202, "OP_UNKNOWN202", 1, opcodeNop},
OP_UNKNOWN203: {OP_UNKNOWN203, "OP_UNKNOWN203", 1, opcodeNop},
OP_UNKNOWN204: {OP_UNKNOWN204, "OP_UNKNOWN204", 1, opcodeNop},
OP_UNKNOWN205: {OP_UNKNOWN205, "OP_UNKNOWN205", 1, opcodeNop},
OP_UNKNOWN206: {OP_UNKNOWN206, "OP_UNKNOWN206", 1, opcodeNop},
OP_UNKNOWN207: {OP_UNKNOWN207, "OP_UNKNOWN207", 1, opcodeNop},
OP_UNKNOWN208: {OP_UNKNOWN208, "OP_UNKNOWN208", 1, opcodeNop},
OP_UNKNOWN209: {OP_UNKNOWN209, "OP_UNKNOWN209", 1, opcodeNop},
OP_UNKNOWN210: {OP_UNKNOWN210, "OP_UNKNOWN210", 1, opcodeNop},
OP_UNKNOWN211: {OP_UNKNOWN211, "OP_UNKNOWN211", 1, opcodeNop},
OP_UNKNOWN212: {OP_UNKNOWN212, "OP_UNKNOWN212", 1, opcodeNop},
OP_UNKNOWN213: {OP_UNKNOWN213, "OP_UNKNOWN213", 1, opcodeNop},
OP_UNKNOWN214: {OP_UNKNOWN214, "OP_UNKNOWN214", 1, opcodeNop},
OP_UNKNOWN215: {OP_UNKNOWN215, "OP_UNKNOWN215", 1, opcodeNop},
OP_UNKNOWN216: {OP_UNKNOWN216, "OP_UNKNOWN216", 1, opcodeNop},
OP_UNKNOWN217: {OP_UNKNOWN217, "OP_UNKNOWN217", 1, opcodeNop},
OP_UNKNOWN218: {OP_UNKNOWN218, "OP_UNKNOWN218", 1, opcodeNop},
OP_UNKNOWN219: {OP_UNKNOWN219, "OP_UNKNOWN219", 1, opcodeNop},
OP_UNKNOWN220: {OP_UNKNOWN220, "OP_UNKNOWN220", 1, opcodeNop},
OP_UNKNOWN221: {OP_UNKNOWN221, "OP_UNKNOWN221", 1, opcodeNop},
OP_UNKNOWN222: {OP_UNKNOWN222, "OP_UNKNOWN222", 1, opcodeNop},
OP_UNKNOWN223: {OP_UNKNOWN223, "OP_UNKNOWN223", 1, opcodeNop},
OP_UNKNOWN224: {OP_UNKNOWN224, "OP_UNKNOWN224", 1, opcodeNop},
OP_UNKNOWN225: {OP_UNKNOWN225, "OP_UNKNOWN225", 1, opcodeNop},
OP_UNKNOWN226: {OP_UNKNOWN226, "OP_UNKNOWN226", 1, opcodeNop},
OP_UNKNOWN227: {OP_UNKNOWN227, "OP_UNKNOWN227", 1, opcodeNop},
OP_UNKNOWN228: {OP_UNKNOWN228, "OP_UNKNOWN228", 1, opcodeNop},
OP_UNKNOWN229: {OP_UNKNOWN229, "OP_UNKNOWN229", 1, opcodeNop},
OP_UNKNOWN230: {OP_UNKNOWN230, "OP_UNKNOWN230", 1, opcodeNop},
OP_UNKNOWN231: {OP_UNKNOWN231, "OP_UNKNOWN231", 1, opcodeNop},
OP_UNKNOWN232: {OP_UNKNOWN232, "OP_UNKNOWN232", 1, opcodeNop},
OP_UNKNOWN233: {OP_UNKNOWN233, "OP_UNKNOWN233", 1, opcodeNop},
OP_UNKNOWN234: {OP_UNKNOWN234, "OP_UNKNOWN234", 1, opcodeNop},
OP_UNKNOWN235: {OP_UNKNOWN235, "OP_UNKNOWN235", 1, opcodeNop},
OP_UNKNOWN236: {OP_UNKNOWN236, "OP_UNKNOWN236", 1, opcodeNop},
OP_UNKNOWN237: {OP_UNKNOWN237, "OP_UNKNOWN237", 1, opcodeNop},
OP_UNKNOWN238: {OP_UNKNOWN238, "OP_UNKNOWN238", 1, opcodeNop},
OP_UNKNOWN239: {OP_UNKNOWN239, "OP_UNKNOWN239", 1, opcodeNop},
OP_UNKNOWN240: {OP_UNKNOWN240, "OP_UNKNOWN240", 1, opcodeNop},
OP_UNKNOWN241: {OP_UNKNOWN241, "OP_UNKNOWN241", 1, opcodeNop},
OP_UNKNOWN242: {OP_UNKNOWN242, "OP_UNKNOWN242", 1, opcodeNop},
OP_UNKNOWN243: {OP_UNKNOWN243, "OP_UNKNOWN243", 1, opcodeNop},
OP_UNKNOWN244: {OP_UNKNOWN244, "OP_UNKNOWN244", 1, opcodeNop},
OP_UNKNOWN245: {OP_UNKNOWN245, "OP_UNKNOWN245", 1, opcodeNop},
OP_UNKNOWN246: {OP_UNKNOWN246, "OP_UNKNOWN246", 1, opcodeNop},
OP_UNKNOWN247: {OP_UNKNOWN247, "OP_UNKNOWN247", 1, opcodeNop},
OP_UNKNOWN248: {OP_UNKNOWN248, "OP_UNKNOWN248", 1, opcodeNop},
// Bitcoin Core internal use opcode. Defined here for completeness.
OP_INVALID249: {OP_INVALID249, "OP_INVALID249", 1, opcodeInvalid},
OP_SMALLINTEGER: {OP_SMALLINTEGER, "OP_SMALLINTEGER", 1, opcodeInvalid},
OP_PUBKEYS: {OP_PUBKEYS, "OP_PUBKEYS", 1, opcodeInvalid},
OP_UNKNOWN252: {OP_UNKNOWN252, "OP_UNKNOWN252", 1, opcodeInvalid},
OP_PUBKEYHASH: {OP_PUBKEYHASH, "OP_PUBKEYHASH", 1, opcodeInvalid},
OP_PUBKEY: {OP_PUBKEY, "OP_PUBKEY", 1, opcodeInvalid},
OP_INVALIDOPCODE: {OP_INVALIDOPCODE, "OP_INVALIDOPCODE", 1, opcodeInvalid},
}
// opcodeOnelineRepls defines opcode names which are replaced when doing a
// one-line disassembly. This is done to match the output of the reference
// implementation while not changing the opcode names in the nicer full
// disassembly.
var opcodeOnelineRepls = map[string]string{
"OP_1NEGATE": "-1",
"OP_0": "0",
"OP_1": "1",
"OP_2": "2",
"OP_3": "3",
"OP_4": "4",
"OP_5": "5",
"OP_6": "6",
"OP_7": "7",
"OP_8": "8",
"OP_9": "9",
"OP_10": "10",
"OP_11": "11",
"OP_12": "12",
"OP_13": "13",
"OP_14": "14",
"OP_15": "15",
"OP_16": "16",
}
// disasmOpcode writes a human-readable disassembly of the provided opcode and
// data into the provided buffer. The compact flag indicates the disassembly
// should print a more compact representation of data-carrying and small integer
// opcodes. For example, OP_0 through OP_16 are replaced with the numeric value
// and data pushes are printed as only the hex representation of the data as
// opposed to including the opcode that specifies the amount of data to push as
// well.
func disasmOpcode(buf *strings.Builder, op *opcode, data []byte, compact bool) {
// Replace opcode which represent values (e.g. OP_0 through OP_16 and
// OP_1NEGATE) with the raw value when performing a compact disassembly.
opcodeName := op.name
if compact {
if replName, ok := opcodeOnelineRepls[opcodeName]; ok {
opcodeName = replName
}
// Either write the human-readable opcode or the parsed data in hex for
// data-carrying opcodes.
switch {
case op.length == 1:
buf.WriteString(opcodeName)
default:
buf.WriteString(hex.EncodeToString(data))
}
return
}
buf.WriteString(opcodeName)
switch op.length {
// Only write the opcode name for non-data push opcodes.
case 1:
return
// Add length for the OP_PUSHDATA# opcodes.
case -1:
buf.WriteString(fmt.Sprintf(" 0x%02x", len(data)))
case -2:
buf.WriteString(fmt.Sprintf(" 0x%04x", len(data)))
case -4:
buf.WriteString(fmt.Sprintf(" 0x%08x", len(data)))
}
buf.WriteString(fmt.Sprintf(" 0x%02x", data))
}
// *******************************************
// Opcode implementation functions start here.
// *******************************************
// opcodeDisabled is a common handler for disabled opcodes. It returns an
// appropriate error indicating the opcode is disabled. While it would
// ordinarily make more sense to detect if the script contains any disabled
// opcodes before executing in an initial parse step, the consensus rules
// dictate the script doesn't fail until the program counter passes over a
// disabled opcode (even when they appear in a branch that is not executed).
func opcodeDisabled(op *opcode, data []byte, vm *Engine) error {
str := fmt.Sprintf("attempt to execute disabled opcode %s", op.name)
return scriptError(ErrDisabledOpcode, str)
}
// opcodeReserved is a common handler for all reserved opcodes. It returns an
// appropriate error indicating the opcode is reserved.
func opcodeReserved(op *opcode, data []byte, vm *Engine) error {
str := fmt.Sprintf("attempt to execute reserved opcode %s", op.name)
return scriptError(ErrReservedOpcode, str)
}
// opcodeInvalid is a common handler for all invalid opcodes. It returns an
// appropriate error indicating the opcode is invalid.
func opcodeInvalid(op *opcode, data []byte, vm *Engine) error {
str := fmt.Sprintf("attempt to execute invalid opcode %s", op.name)
return scriptError(ErrReservedOpcode, str)
}
// opcodeFalse pushes an empty array to the data stack to represent false. Note
// that 0, when encoded as a number according to the numeric encoding consensus
// rules, is an empty array.
func opcodeFalse(op *opcode, data []byte, vm *Engine) error {
vm.dstack.PushByteArray(nil)
return nil
}
// opcodePushData is a common handler for the vast majority of opcodes that push
// raw data (bytes) to the data stack.
func opcodePushData(op *opcode, data []byte, vm *Engine) error {
vm.dstack.PushByteArray(data)
return nil
}
// opcode1Negate pushes -1, encoded as a number, to the data stack.
func opcode1Negate(op *opcode, data []byte, vm *Engine) error {
vm.dstack.PushInt(ScriptNum(-1))
return nil
}
// opcodeN is a common handler for the small integer data push opcodes. It
// pushes the numeric value the opcode represents (which will be from 1 to 16)
// onto the data stack.
func opcodeN(op *opcode, data []byte, vm *Engine) error {
// The opcodes are all defined consecutively, so the numeric value is
// the difference.
vm.dstack.PushInt(ScriptNum((op.value - (OP_1 - 1))))
return nil
}
// opcodeNop is a common handler for the NOP family of opcodes. As the name
// implies it generally does nothing, however, it will return an error when
// the flag to discourage use of NOPs is set for select opcodes.
func opcodeNop(op *opcode, data []byte, vm *Engine) error {
switch op.value {
case OP_NOP1, OP_NOP4, OP_NOP5, OP_NOP6,
OP_NOP7, OP_NOP8, OP_NOP9, OP_NOP10,
OP_UNKNOWN196, OP_UNKNOWN197, OP_UNKNOWN198, OP_UNKNOWN199,
OP_UNKNOWN200, OP_UNKNOWN201, OP_UNKNOWN202, OP_UNKNOWN203,
OP_UNKNOWN204, OP_UNKNOWN205, OP_UNKNOWN206, OP_UNKNOWN207,
OP_UNKNOWN208, OP_UNKNOWN209, OP_UNKNOWN210, OP_UNKNOWN211,
OP_UNKNOWN212, OP_UNKNOWN213, OP_UNKNOWN214, OP_UNKNOWN215,
OP_UNKNOWN216, OP_UNKNOWN217, OP_UNKNOWN218, OP_UNKNOWN219,
OP_UNKNOWN220, OP_UNKNOWN221, OP_UNKNOWN222, OP_UNKNOWN223,
OP_UNKNOWN224, OP_UNKNOWN225, OP_UNKNOWN226, OP_UNKNOWN227,
OP_UNKNOWN228, OP_UNKNOWN229, OP_UNKNOWN230, OP_UNKNOWN231,
OP_UNKNOWN232, OP_UNKNOWN233, OP_UNKNOWN234, OP_UNKNOWN235,
OP_UNKNOWN236, OP_UNKNOWN237, OP_UNKNOWN238, OP_UNKNOWN239,
OP_UNKNOWN240, OP_UNKNOWN241, OP_UNKNOWN242, OP_UNKNOWN243,
OP_UNKNOWN244, OP_UNKNOWN245, OP_UNKNOWN246, OP_UNKNOWN247,
OP_UNKNOWN248:
if vm.hasFlag(ScriptDiscourageUpgradableNops) {
str := fmt.Sprintf("%s reserved for upgrades", op.name)
return scriptError(ErrDiscourageUpgradableNOPs, str)
}
}
return nil
}
// opcodeIf treats the top item on the data stack as a boolean and removes it.
//
// An appropriate entry is added to the conditional stack depending on whether
// the boolean is true and whether this if is on an executing branch in order
// to allow proper execution of further opcodes depending on the conditional
// logic. When the boolean is true, the first branch will be executed (unless
// this opcode is nested in a non-executed branch).
//
// <expression> if [statements] [else [statements]] endif
//
// Note that, unlike for all non-conditional opcodes, this is executed even when
// it is on a non-executing branch so proper nesting is maintained.
//
// Data stack transformation: [... bool] -> [...]
func opcodeIf(op *opcode, data []byte, vm *Engine) error {
if vm.isBranchExecuting() {
ok, err := vm.dstack.PopBool()
if err != nil {
return err
}
if !ok {
// Branch execution is being disabled when it was not previously, so
// mark the current conditional nesting depth as the depth at which
// it was disabled.
vm.condDisableDepth = vm.condNestDepth
}
}
// Increment the conditional execution nesting depth to account for the
// conditional opcode.
vm.condNestDepth++
return nil
}
// opcodeNotIf treats the top item on the data stack as a boolean and removes
// it.
//
// An appropriate entry is added to the conditional stack depending on whether
// the boolean is true and whether this if is on an executing branch in order
// to allow proper execution of further opcodes depending on the conditional
// logic. When the boolean is false, the first branch will be executed (unless
// this opcode is nested in a non-executed branch).
//
// <expression> notif [statements] [else [statements]] endif
//
// Note that, unlike for all non-conditional opcodes, this is executed even when
// it is on a non-executing branch so proper nesting is maintained.
//
// Data stack transformation: [... bool] -> [...]
func opcodeNotIf(op *opcode, data []byte, vm *Engine) error {
if vm.isBranchExecuting() {
ok, err := vm.dstack.PopBool()
if err != nil {
return err
}
if ok {
// Branch execution is being disabled when it was not previously, so
// mark the current conditional nesting depth as the depth at which
// it was disabled.
vm.condDisableDepth = vm.condNestDepth
}
}
// Increment the conditional execution nesting depth to account for the
// conditional opcode.
vm.condNestDepth++
return nil
}
// opcodeElse inverts conditional execution for other half of if/else/endif.
//
// An error is returned if there has not already been a matching OP_IF.
func opcodeElse(op *opcode, data []byte, vm *Engine) error {
if vm.condNestDepth == 0 {
str := fmt.Sprintf("encountered opcode %s with no matching "+
"opcode to begin conditional execution", op.name)
return scriptError(ErrUnbalancedConditional, str)
}
conditionalDepth := vm.condNestDepth - 1
switch {
case vm.isBranchExecuting():
// Branch execution is being disabled when it was not previously, so
// mark the most recent conditional nesting depth as the depth at which
// it was disabled.
vm.condDisableDepth = conditionalDepth
case vm.condDisableDepth == conditionalDepth:
// Enable branch execution when it was previously disabled as a result
// of the opcode at the depth that is being toggled.
vm.condDisableDepth = noCondDisableDepth
default:
// No effect since this opcode is nested in a non-executed branch.
}
return nil
}
// opcodeEndif terminates a conditional block, removing the value from the
// conditional execution stack.
//
// An error is returned if there has not already been a matching OP_IF.
func opcodeEndif(op *opcode, data []byte, vm *Engine) error {
if vm.condNestDepth == 0 {
str := fmt.Sprintf("encountered opcode %s with no matching "+
"opcode to begin conditional execution", op.name)
return scriptError(ErrUnbalancedConditional, str)
}
// Decrement the conditional execution nesting depth and enable branch
// execution if it was previously disabled as a result of the opcode at
// that depth.
vm.condNestDepth--
if vm.condDisableDepth == vm.condNestDepth {
vm.condDisableDepth = noCondDisableDepth
}
return nil
}
// abstractVerify examines the top item on the data stack as a boolean value and
// verifies it evaluates to true. An error is returned either when there is no
// item on the stack or when that item evaluates to false. In the latter case
// where the verification fails specifically due to the top item evaluating
// to false, the returned error will use the passed error kind.
func abstractVerify(op *opcode, vm *Engine, kind ErrorKind) error {
verified, err := vm.dstack.PopBool()
if err != nil {
return err
}
if !verified {
str := fmt.Sprintf("%s failed", op.name)
return scriptError(kind, str)
}
return nil
}
// opcodeVerify examines the top item on the data stack as a boolean value and
// verifies it evaluates to true. An error is returned if it does not.
func opcodeVerify(op *opcode, data []byte, vm *Engine) error {
return abstractVerify(op, vm, ErrVerify)
}
// opcodeReturn returns an appropriate error since it is always an error to
// return early from a script.
func opcodeReturn(op *opcode, data []byte, vm *Engine) error {
return scriptError(ErrEarlyReturn, "script returned early")
}
// verifyLockTime is a helper function used to validate locktimes.
func verifyLockTime(txLockTime, threshold, lockTime int64) error {
// The lockTimes in both the script and transaction must be of the same
// type.
if !((txLockTime < threshold && lockTime < threshold) ||
(txLockTime >= threshold && lockTime >= threshold)) {
str := fmt.Sprintf("mismatched locktime types -- tx locktime "+
"%d, stack locktime %d", txLockTime, lockTime)
return scriptError(ErrUnsatisfiedLockTime, str)
}
if lockTime > txLockTime {
str := fmt.Sprintf("locktime requirement not satisfied -- "+
"locktime is greater than the transaction locktime: "+
"%d > %d", lockTime, txLockTime)
return scriptError(ErrUnsatisfiedLockTime, str)
}
return nil
}
// opcodeCheckLockTimeVerify compares the top item on the data stack to the
// LockTime field of the transaction containing the script signature
// validating if the transaction outputs are spendable yet. If flag
// ScriptVerifyCheckLockTimeVerify is not set, the code continues as if OP_NOP2
// were executed.
func opcodeCheckLockTimeVerify(op *opcode, data []byte, vm *Engine) error {
// If the ScriptVerifyCheckLockTimeVerify script flag is not set, treat
// opcode as OP_NOP2 instead.
if !vm.hasFlag(ScriptVerifyCheckLockTimeVerify) {
if vm.hasFlag(ScriptDiscourageUpgradableNops) {
return scriptError(ErrDiscourageUpgradableNOPs,
"OP_NOP2 reserved for soft-fork upgrades")
}
return nil
}
// The current transaction locktime is a uint32 resulting in a maximum
// locktime of 2^32-1 (the year 2106). However, ScriptNums are signed
// and therefore a standard 4-byte ScriptNum would only support up to a
// maximum of 2^31-1 (the year 2038). Thus, a 5-byte ScriptNum is used
// here since it will support up to 2^39-1 which allows dates beyond the
// current locktime limit.
lockTime, err := vm.dstack.PeekInt(0, CltvMaxScriptNumLen)
if err != nil {
return err
}
// In the rare event that the argument needs to be < 0 due to some
// arithmetic being done first, you can always use
// 0 OP_MAX OP_CHECKLOCKTIMEVERIFY.
if lockTime < 0 {
str := fmt.Sprintf("negative lock time: %d", lockTime)
return scriptError(ErrNegativeLockTime, str)
}
// The lock time field of a transaction is either a block height at
// which the transaction is finalized or a timestamp depending on if the
// value is before the txscript.LockTimeThreshold. When it is under the
// threshold it is a block height.
err = verifyLockTime(int64(vm.tx.LockTime), LockTimeThreshold,
int64(lockTime))
if err != nil {
return err
}
// The lock time feature can also be disabled, thereby bypassing
// OP_CHECKLOCKTIMEVERIFY, if every transaction input has been finalized by
// setting its sequence to the maximum value (wire.MaxTxInSequenceNum). This
// condition would result in the transaction being allowed into the blockchain
// making the opcode ineffective.
//
// This condition is prevented by enforcing that the input being used by
// the opcode is unlocked (its sequence number is less than the max
// value). This is sufficient to prove correctness without having to
// check every input.
//
// NOTE: This implies that even if the transaction is not finalized due to
// another input being unlocked, the opcode execution will still fail when the
// input being used by the opcode is locked.
if vm.tx.TxIn[vm.txIdx].Sequence == wire.MaxTxInSequenceNum {
return scriptError(ErrUnsatisfiedLockTime,
"transaction input is finalized")
}
return nil