/
opcode.go
2495 lines (2250 loc) · 81.2 KB
/
opcode.go
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// Copyright (c) 2013-2017 The btcsuite 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/sha256"
"encoding/binary"
"fmt"
"hash"
"github.com/BTCGhostdag/BTCD/domain/consensus/utils/consensushashing"
"golang.org/x/crypto/blake2b"
"github.com/BTCGhostdag/BTCD/domain/consensus/utils/constants"
"github.com/kaspanet/go-secp256k1"
)
// 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(*parsedOpcode, *Engine) error
}
// These constants are the values of the kaspa script opcodes.
const (
Op0 = 0x00 // 0
OpFalse = 0x00 // 0 - AKA Op0
OpData1 = 0x01 // 1
OpData2 = 0x02 // 2
OpData3 = 0x03 // 3
OpData4 = 0x04 // 4
OpData5 = 0x05 // 5
OpData6 = 0x06 // 6
OpData7 = 0x07 // 7
OpData8 = 0x08 // 8
OpData9 = 0x09 // 9
OpData10 = 0x0a // 10
OpData11 = 0x0b // 11
OpData12 = 0x0c // 12
OpData13 = 0x0d // 13
OpData14 = 0x0e // 14
OpData15 = 0x0f // 15
OpData16 = 0x10 // 16
OpData17 = 0x11 // 17
OpData18 = 0x12 // 18
OpData19 = 0x13 // 19
OpData20 = 0x14 // 20
OpData21 = 0x15 // 21
OpData22 = 0x16 // 22
OpData23 = 0x17 // 23
OpData24 = 0x18 // 24
OpData25 = 0x19 // 25
OpData26 = 0x1a // 26
OpData27 = 0x1b // 27
OpData28 = 0x1c // 28
OpData29 = 0x1d // 29
OpData30 = 0x1e // 30
OpData31 = 0x1f // 31
OpData32 = 0x20 // 32
OpData33 = 0x21 // 33
OpData34 = 0x22 // 34
OpData35 = 0x23 // 35
OpData36 = 0x24 // 36
OpData37 = 0x25 // 37
OpData38 = 0x26 // 38
OpData39 = 0x27 // 39
OpData40 = 0x28 // 40
OpData41 = 0x29 // 41
OpData42 = 0x2a // 42
OpData43 = 0x2b // 43
OpData44 = 0x2c // 44
OpData45 = 0x2d // 45
OpData46 = 0x2e // 46
OpData47 = 0x2f // 47
OpData48 = 0x30 // 48
OpData49 = 0x31 // 49
OpData50 = 0x32 // 50
OpData51 = 0x33 // 51
OpData52 = 0x34 // 52
OpData53 = 0x35 // 53
OpData54 = 0x36 // 54
OpData55 = 0x37 // 55
OpData56 = 0x38 // 56
OpData57 = 0x39 // 57
OpData58 = 0x3a // 58
OpData59 = 0x3b // 59
OpData60 = 0x3c // 60
OpData61 = 0x3d // 61
OpData62 = 0x3e // 62
OpData63 = 0x3f // 63
OpData64 = 0x40 // 64
OpData65 = 0x41 // 65
OpData66 = 0x42 // 66
OpData67 = 0x43 // 67
OpData68 = 0x44 // 68
OpData69 = 0x45 // 69
OpData70 = 0x46 // 70
OpData71 = 0x47 // 71
OpData72 = 0x48 // 72
OpData73 = 0x49 // 73
OpData74 = 0x4a // 74
OpData75 = 0x4b // 75
OpPushData1 = 0x4c // 76
OpPushData2 = 0x4d // 77
OpPushData4 = 0x4e // 78
Op1Negate = 0x4f // 79
OpReserved = 0x50 // 80
Op1 = 0x51 // 81 - AKA OpTrue
OpTrue = 0x51 // 81
Op2 = 0x52 // 82
Op3 = 0x53 // 83
Op4 = 0x54 // 84
Op5 = 0x55 // 85
Op6 = 0x56 // 86
Op7 = 0x57 // 87
Op8 = 0x58 // 88
Op9 = 0x59 // 89
Op10 = 0x5a // 90
Op11 = 0x5b // 91
Op12 = 0x5c // 92
Op13 = 0x5d // 93
Op14 = 0x5e // 94
Op15 = 0x5f // 95
Op16 = 0x60 // 96
OpNop = 0x61 // 97
OpVer = 0x62 // 98
OpIf = 0x63 // 99
OpNotIf = 0x64 // 100
OpVerIf = 0x65 // 101
OpVerNotIf = 0x66 // 102
OpElse = 0x67 // 103
OpEndIf = 0x68 // 104
OpVerify = 0x69 // 105
OpReturn = 0x6a // 106
OpToAltStack = 0x6b // 107
OpFromAltStack = 0x6c // 108
Op2Drop = 0x6d // 109
Op2Dup = 0x6e // 110
Op3Dup = 0x6f // 111
Op2Over = 0x70 // 112
Op2Rot = 0x71 // 113
Op2Swap = 0x72 // 114
OpIfDup = 0x73 // 115
OpDepth = 0x74 // 116
OpDrop = 0x75 // 117
OpDup = 0x76 // 118
OpNip = 0x77 // 119
OpOver = 0x78 // 120
OpPick = 0x79 // 121
OpRoll = 0x7a // 122
OpRot = 0x7b // 123
OpSwap = 0x7c // 124
OpTuck = 0x7d // 125
OpCat = 0x7e // 126
OpSubStr = 0x7f // 127
OpLeft = 0x80 // 128
OpRight = 0x81 // 129
OpSize = 0x82 // 130
OpInvert = 0x83 // 131
OpAnd = 0x84 // 132
OpOr = 0x85 // 133
OpXor = 0x86 // 134
OpEqual = 0x87 // 135
OpEqualVerify = 0x88 // 136
OpReserved1 = 0x89 // 137
OpReserved2 = 0x8a // 138
Op1Add = 0x8b // 139
Op1Sub = 0x8c // 140
Op2Mul = 0x8d // 141
Op2Div = 0x8e // 142
OpNegate = 0x8f // 143
OpAbs = 0x90 // 144
OpNot = 0x91 // 145
Op0NotEqual = 0x92 // 146
OpAdd = 0x93 // 147
OpSub = 0x94 // 148
OpMul = 0x95 // 149
OpDiv = 0x96 // 150
OpMod = 0x97 // 151
OpLShift = 0x98 // 152
OpRShift = 0x99 // 153
OpBoolAnd = 0x9a // 154
OpBoolOr = 0x9b // 155
OpNumEqual = 0x9c // 156
OpNumEqualVerify = 0x9d // 157
OpNumNotEqual = 0x9e // 158
OpLessThan = 0x9f // 159
OpGreaterThan = 0xa0 // 160
OpLessThanOrEqual = 0xa1 // 161
OpGreaterThanOrEqual = 0xa2 // 162
OpMin = 0xa3 // 163
OpMax = 0xa4 // 164
OpWithin = 0xa5 // 165
OpUnknown166 = 0xa6 // 166
OpUnknown167 = 0xa7 // 167
OpSHA256 = 0xa8 // 168
OpCheckMultiSigECDSA = 0xa9 // 169
OpBlake2b = 0xaa // 170
OpCheckSigECDSA = 0xab // 171
OpCheckSig = 0xac // 172
OpCheckSigVerify = 0xad // 173
OpCheckMultiSig = 0xae // 174
OpCheckMultiSigVerify = 0xaf // 175
OpCheckLockTimeVerify = 0xb0 // 176
OpCheckSequenceVerify = 0xb1 // 177
OpUnknown178 = 0xb2 // 178
OpUnknown179 = 0xb3 // 179
OpUnknown180 = 0xb4 // 180
OpUnknown181 = 0xb5 // 181
OpUnknown182 = 0xb6 // 182
OpUnknown183 = 0xb7 // 183
OpUnknown184 = 0xb8 // 184
OpUnknown185 = 0xb9 // 185
OpUnknown186 = 0xba // 186
OpUnknown187 = 0xbb // 187
OpUnknown188 = 0xbc // 188
OpUnknown189 = 0xbd // 189
OpUnknown190 = 0xbe // 190
OpUnknown191 = 0xbf // 191
OpUnknown192 = 0xc0 // 192
OpUnknown193 = 0xc1 // 193
OpUnknown194 = 0xc2 // 194
OpUnknown195 = 0xc3 // 195
OpUnknown196 = 0xc4 // 196
OpUnknown197 = 0xc5 // 197
OpUnknown198 = 0xc6 // 198
OpUnknown199 = 0xc7 // 199
OpUnknown200 = 0xc8 // 200
OpUnknown201 = 0xc9 // 201
OpUnknown202 = 0xca // 202
OpUnknown203 = 0xcb // 203
OpUnknown204 = 0xcc // 204
OpUnknown205 = 0xcd // 205
OpUnknown206 = 0xce // 206
OpUnknown207 = 0xcf // 207
OpUnknown208 = 0xd0 // 208
OpUnknown209 = 0xd1 // 209
OpUnknown210 = 0xd2 // 210
OpUnknown211 = 0xd3 // 211
OpUnknown212 = 0xd4 // 212
OpUnknown213 = 0xd5 // 213
OpUnknown214 = 0xd6 // 214
OpUnknown215 = 0xd7 // 215
OpUnknown216 = 0xd8 // 216
OpUnknown217 = 0xd9 // 217
OpUnknown218 = 0xda // 218
OpUnknown219 = 0xdb // 219
OpUnknown220 = 0xdc // 220
OpUnknown221 = 0xdd // 221
OpUnknown222 = 0xde // 222
OpUnknown223 = 0xdf // 223
OpUnknown224 = 0xe0 // 224
OpUnknown225 = 0xe1 // 225
OpUnknown226 = 0xe2 // 226
OpUnknown227 = 0xe3 // 227
OpUnknown228 = 0xe4 // 228
OpUnknown229 = 0xe5 // 229
OpUnknown230 = 0xe6 // 230
OpUnknown231 = 0xe7 // 231
OpUnknown232 = 0xe8 // 232
OpUnknown233 = 0xe9 // 233
OpUnknown234 = 0xea // 234
OpUnknown235 = 0xeb // 235
OpUnknown236 = 0xec // 236
OpUnknown237 = 0xed // 237
OpUnknown238 = 0xee // 238
OpUnknown239 = 0xef // 239
OpUnknown240 = 0xf0 // 240
OpUnknown241 = 0xf1 // 241
OpUnknown242 = 0xf2 // 242
OpUnknown243 = 0xf3 // 243
OpUnknown244 = 0xf4 // 244
OpUnknown245 = 0xf5 // 245
OpUnknown246 = 0xf6 // 246
OpUnknown247 = 0xf7 // 247
OpUnknown248 = 0xf8 // 248
OpUnknown249 = 0xf9 // 249
OpSmallInteger = 0xfa // 250
OpPubKeys = 0xfb // 251
OpUnknown252 = 0xfc // 252
OpPubKeyHash = 0xfd // 253
OpPubKey = 0xfe // 254
OpInvalidOpCode = 0xff // 255
)
// Conditional execution constants.
const (
OpCondFalse = 0
OpCondTrue = 1
OpCondSkip = 2
)
// 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.
OpFalse: {OpFalse, "OP_0", 1, opcodeFalse},
OpData1: {OpData1, "OP_DATA_1", 2, opcodePushData},
OpData2: {OpData2, "OP_DATA_2", 3, opcodePushData},
OpData3: {OpData3, "OP_DATA_3", 4, opcodePushData},
OpData4: {OpData4, "OP_DATA_4", 5, opcodePushData},
OpData5: {OpData5, "OP_DATA_5", 6, opcodePushData},
OpData6: {OpData6, "OP_DATA_6", 7, opcodePushData},
OpData7: {OpData7, "OP_DATA_7", 8, opcodePushData},
OpData8: {OpData8, "OP_DATA_8", 9, opcodePushData},
OpData9: {OpData9, "OP_DATA_9", 10, opcodePushData},
OpData10: {OpData10, "OP_DATA_10", 11, opcodePushData},
OpData11: {OpData11, "OP_DATA_11", 12, opcodePushData},
OpData12: {OpData12, "OP_DATA_12", 13, opcodePushData},
OpData13: {OpData13, "OP_DATA_13", 14, opcodePushData},
OpData14: {OpData14, "OP_DATA_14", 15, opcodePushData},
OpData15: {OpData15, "OP_DATA_15", 16, opcodePushData},
OpData16: {OpData16, "OP_DATA_16", 17, opcodePushData},
OpData17: {OpData17, "OP_DATA_17", 18, opcodePushData},
OpData18: {OpData18, "OP_DATA_18", 19, opcodePushData},
OpData19: {OpData19, "OP_DATA_19", 20, opcodePushData},
OpData20: {OpData20, "OP_DATA_20", 21, opcodePushData},
OpData21: {OpData21, "OP_DATA_21", 22, opcodePushData},
OpData22: {OpData22, "OP_DATA_22", 23, opcodePushData},
OpData23: {OpData23, "OP_DATA_23", 24, opcodePushData},
OpData24: {OpData24, "OP_DATA_24", 25, opcodePushData},
OpData25: {OpData25, "OP_DATA_25", 26, opcodePushData},
OpData26: {OpData26, "OP_DATA_26", 27, opcodePushData},
OpData27: {OpData27, "OP_DATA_27", 28, opcodePushData},
OpData28: {OpData28, "OP_DATA_28", 29, opcodePushData},
OpData29: {OpData29, "OP_DATA_29", 30, opcodePushData},
OpData30: {OpData30, "OP_DATA_30", 31, opcodePushData},
OpData31: {OpData31, "OP_DATA_31", 32, opcodePushData},
OpData32: {OpData32, "OP_DATA_32", 33, opcodePushData},
OpData33: {OpData33, "OP_DATA_33", 34, opcodePushData},
OpData34: {OpData34, "OP_DATA_34", 35, opcodePushData},
OpData35: {OpData35, "OP_DATA_35", 36, opcodePushData},
OpData36: {OpData36, "OP_DATA_36", 37, opcodePushData},
OpData37: {OpData37, "OP_DATA_37", 38, opcodePushData},
OpData38: {OpData38, "OP_DATA_38", 39, opcodePushData},
OpData39: {OpData39, "OP_DATA_39", 40, opcodePushData},
OpData40: {OpData40, "OP_DATA_40", 41, opcodePushData},
OpData41: {OpData41, "OP_DATA_41", 42, opcodePushData},
OpData42: {OpData42, "OP_DATA_42", 43, opcodePushData},
OpData43: {OpData43, "OP_DATA_43", 44, opcodePushData},
OpData44: {OpData44, "OP_DATA_44", 45, opcodePushData},
OpData45: {OpData45, "OP_DATA_45", 46, opcodePushData},
OpData46: {OpData46, "OP_DATA_46", 47, opcodePushData},
OpData47: {OpData47, "OP_DATA_47", 48, opcodePushData},
OpData48: {OpData48, "OP_DATA_48", 49, opcodePushData},
OpData49: {OpData49, "OP_DATA_49", 50, opcodePushData},
OpData50: {OpData50, "OP_DATA_50", 51, opcodePushData},
OpData51: {OpData51, "OP_DATA_51", 52, opcodePushData},
OpData52: {OpData52, "OP_DATA_52", 53, opcodePushData},
OpData53: {OpData53, "OP_DATA_53", 54, opcodePushData},
OpData54: {OpData54, "OP_DATA_54", 55, opcodePushData},
OpData55: {OpData55, "OP_DATA_55", 56, opcodePushData},
OpData56: {OpData56, "OP_DATA_56", 57, opcodePushData},
OpData57: {OpData57, "OP_DATA_57", 58, opcodePushData},
OpData58: {OpData58, "OP_DATA_58", 59, opcodePushData},
OpData59: {OpData59, "OP_DATA_59", 60, opcodePushData},
OpData60: {OpData60, "OP_DATA_60", 61, opcodePushData},
OpData61: {OpData61, "OP_DATA_61", 62, opcodePushData},
OpData62: {OpData62, "OP_DATA_62", 63, opcodePushData},
OpData63: {OpData63, "OP_DATA_63", 64, opcodePushData},
OpData64: {OpData64, "OP_DATA_64", 65, opcodePushData},
OpData65: {OpData65, "OP_DATA_65", 66, opcodePushData},
OpData66: {OpData66, "OP_DATA_66", 67, opcodePushData},
OpData67: {OpData67, "OP_DATA_67", 68, opcodePushData},
OpData68: {OpData68, "OP_DATA_68", 69, opcodePushData},
OpData69: {OpData69, "OP_DATA_69", 70, opcodePushData},
OpData70: {OpData70, "OP_DATA_70", 71, opcodePushData},
OpData71: {OpData71, "OP_DATA_71", 72, opcodePushData},
OpData72: {OpData72, "OP_DATA_72", 73, opcodePushData},
OpData73: {OpData73, "OP_DATA_73", 74, opcodePushData},
OpData74: {OpData74, "OP_DATA_74", 75, opcodePushData},
OpData75: {OpData75, "OP_DATA_75", 76, opcodePushData},
OpPushData1: {OpPushData1, "OP_PUSHDATA1", -1, opcodePushData},
OpPushData2: {OpPushData2, "OP_PUSHDATA2", -2, opcodePushData},
OpPushData4: {OpPushData4, "OP_PUSHDATA4", -4, opcodePushData},
Op1Negate: {Op1Negate, "OP_1NEGATE", 1, opcode1Negate},
OpReserved: {OpReserved, "OP_RESERVED", 1, opcodeReserved},
OpTrue: {OpTrue, "OP_1", 1, opcodeN},
Op2: {Op2, "OP_2", 1, opcodeN},
Op3: {Op3, "OP_3", 1, opcodeN},
Op4: {Op4, "OP_4", 1, opcodeN},
Op5: {Op5, "OP_5", 1, opcodeN},
Op6: {Op6, "OP_6", 1, opcodeN},
Op7: {Op7, "OP_7", 1, opcodeN},
Op8: {Op8, "OP_8", 1, opcodeN},
Op9: {Op9, "OP_9", 1, opcodeN},
Op10: {Op10, "OP_10", 1, opcodeN},
Op11: {Op11, "OP_11", 1, opcodeN},
Op12: {Op12, "OP_12", 1, opcodeN},
Op13: {Op13, "OP_13", 1, opcodeN},
Op14: {Op14, "OP_14", 1, opcodeN},
Op15: {Op15, "OP_15", 1, opcodeN},
Op16: {Op16, "OP_16", 1, opcodeN},
// Control opcodes.
OpNop: {OpNop, "OP_NOP", 1, opcodeNop},
OpVer: {OpVer, "OP_VER", 1, opcodeReserved},
OpIf: {OpIf, "OP_IF", 1, opcodeIf},
OpNotIf: {OpNotIf, "OP_NOTIF", 1, opcodeNotIf},
OpVerIf: {OpVerIf, "OP_VERIF", 1, opcodeReserved},
OpVerNotIf: {OpVerNotIf, "OP_VERNOTIF", 1, opcodeReserved},
OpElse: {OpElse, "OP_ELSE", 1, opcodeElse},
OpEndIf: {OpEndIf, "OP_ENDIF", 1, opcodeEndif},
OpVerify: {OpVerify, "OP_VERIFY", 1, opcodeVerify},
OpReturn: {OpReturn, "OP_RETURN", 1, opcodeReturn},
OpCheckLockTimeVerify: {OpCheckLockTimeVerify, "OP_CHECKLOCKTIMEVERIFY", 1, opcodeCheckLockTimeVerify},
OpCheckSequenceVerify: {OpCheckSequenceVerify, "OP_CHECKSEQUENCEVERIFY", 1, opcodeCheckSequenceVerify},
// Stack opcodes.
OpToAltStack: {OpToAltStack, "OP_TOALTSTACK", 1, opcodeToAltStack},
OpFromAltStack: {OpFromAltStack, "OP_FROMALTSTACK", 1, opcodeFromAltStack},
Op2Drop: {Op2Drop, "OP_2DROP", 1, opcode2Drop},
Op2Dup: {Op2Dup, "OP_2DUP", 1, opcode2Dup},
Op3Dup: {Op3Dup, "OP_3DUP", 1, opcode3Dup},
Op2Over: {Op2Over, "OP_2OVER", 1, opcode2Over},
Op2Rot: {Op2Rot, "OP_2ROT", 1, opcode2Rot},
Op2Swap: {Op2Swap, "OP_2SWAP", 1, opcode2Swap},
OpIfDup: {OpIfDup, "OP_IFDUP", 1, opcodeIfDup},
OpDepth: {OpDepth, "OP_DEPTH", 1, opcodeDepth},
OpDrop: {OpDrop, "OP_DROP", 1, opcodeDrop},
OpDup: {OpDup, "OP_DUP", 1, opcodeDup},
OpNip: {OpNip, "OP_NIP", 1, opcodeNip},
OpOver: {OpOver, "OP_OVER", 1, opcodeOver},
OpPick: {OpPick, "OP_PICK", 1, opcodePick},
OpRoll: {OpRoll, "OP_ROLL", 1, opcodeRoll},
OpRot: {OpRot, "OP_ROT", 1, opcodeRot},
OpSwap: {OpSwap, "OP_SWAP", 1, opcodeSwap},
OpTuck: {OpTuck, "OP_TUCK", 1, opcodeTuck},
// Splice opcodes.
OpCat: {OpCat, "OP_CAT", 1, opcodeDisabled},
OpSubStr: {OpSubStr, "OP_SUBSTR", 1, opcodeDisabled},
OpLeft: {OpLeft, "OP_LEFT", 1, opcodeDisabled},
OpRight: {OpRight, "OP_RIGHT", 1, opcodeDisabled},
OpSize: {OpSize, "OP_SIZE", 1, opcodeSize},
// Bitwise logic opcodes.
OpInvert: {OpInvert, "OP_INVERT", 1, opcodeDisabled},
OpAnd: {OpAnd, "OP_AND", 1, opcodeDisabled},
OpOr: {OpOr, "OP_OR", 1, opcodeDisabled},
OpXor: {OpXor, "OP_XOR", 1, opcodeDisabled},
OpEqual: {OpEqual, "OP_EQUAL", 1, opcodeEqual},
OpEqualVerify: {OpEqualVerify, "OP_EQUALVERIFY", 1, opcodeEqualVerify},
OpReserved1: {OpReserved1, "OP_RESERVED1", 1, opcodeReserved},
OpReserved2: {OpReserved2, "OP_RESERVED2", 1, opcodeReserved},
// Numeric related opcodes.
Op1Add: {Op1Add, "OP_1ADD", 1, opcode1Add},
Op1Sub: {Op1Sub, "OP_1SUB", 1, opcode1Sub},
Op2Mul: {Op2Mul, "OP_2MUL", 1, opcodeDisabled},
Op2Div: {Op2Div, "OP_2DIV", 1, opcodeDisabled},
OpNegate: {OpNegate, "OP_NEGATE", 1, opcodeNegate},
OpAbs: {OpAbs, "OP_ABS", 1, opcodeAbs},
OpNot: {OpNot, "OP_NOT", 1, opcodeNot},
Op0NotEqual: {Op0NotEqual, "OP_0NOTEQUAL", 1, opcode0NotEqual},
OpAdd: {OpAdd, "OP_ADD", 1, opcodeAdd},
OpSub: {OpSub, "OP_SUB", 1, opcodeSub},
OpMul: {OpMul, "OP_MUL", 1, opcodeDisabled},
OpDiv: {OpDiv, "OP_DIV", 1, opcodeDisabled},
OpMod: {OpMod, "OP_MOD", 1, opcodeDisabled},
OpLShift: {OpLShift, "OP_LSHIFT", 1, opcodeDisabled},
OpRShift: {OpRShift, "OP_RSHIFT", 1, opcodeDisabled},
OpBoolAnd: {OpBoolAnd, "OP_BOOLAND", 1, opcodeBoolAnd},
OpBoolOr: {OpBoolOr, "OP_BOOLOR", 1, opcodeBoolOr},
OpNumEqual: {OpNumEqual, "OP_NUMEQUAL", 1, opcodeNumEqual},
OpNumEqualVerify: {OpNumEqualVerify, "OP_NUMEQUALVERIFY", 1, opcodeNumEqualVerify},
OpNumNotEqual: {OpNumNotEqual, "OP_NUMNOTEQUAL", 1, opcodeNumNotEqual},
OpLessThan: {OpLessThan, "OP_LESSTHAN", 1, opcodeLessThan},
OpGreaterThan: {OpGreaterThan, "OP_GREATERTHAN", 1, opcodeGreaterThan},
OpLessThanOrEqual: {OpLessThanOrEqual, "OP_LESSTHANOREQUAL", 1, opcodeLessThanOrEqual},
OpGreaterThanOrEqual: {OpGreaterThanOrEqual, "OP_GREATERTHANOREQUAL", 1, opcodeGreaterThanOrEqual},
OpMin: {OpMin, "OP_MIN", 1, opcodeMin},
OpMax: {OpMax, "OP_MAX", 1, opcodeMax},
OpWithin: {OpWithin, "OP_WITHIN", 1, opcodeWithin},
// Crypto opcodes.
OpCheckMultiSigECDSA: {OpCheckMultiSigECDSA, "OP_CHECKMULTISIGECDSA", 1, opcodeCheckMultiSigECDSA},
OpSHA256: {OpSHA256, "OP_SHA256", 1, opcodeSha256},
OpBlake2b: {OpBlake2b, "OP_BLAKE2B", 1, opcodeBlake2b},
OpCheckSigECDSA: {OpCheckSigECDSA, "OP_CHECKSIGECDSA", 1, opcodeCheckSigECDSA},
OpCheckSig: {OpCheckSig, "OP_CHECKSIG", 1, opcodeCheckSig},
OpCheckSigVerify: {OpCheckSigVerify, "OP_CHECKSIGVERIFY", 1, opcodeCheckSigVerify},
OpCheckMultiSig: {OpCheckMultiSig, "OP_CHECKMULTISIG", 1, opcodeCheckMultiSig},
OpCheckMultiSigVerify: {OpCheckMultiSigVerify, "OP_CHECKMULTISIGVERIFY", 1, opcodeCheckMultiSigVerify},
// Undefined opcodes.
OpUnknown166: {OpUnknown166, "OP_UNKNOWN166", 1, opcodeInvalid},
OpUnknown167: {OpUnknown167, "OP_UNKNOWN167", 1, opcodeInvalid},
OpUnknown178: {OpUnknown188, "OP_UNKNOWN178", 1, opcodeInvalid},
OpUnknown179: {OpUnknown189, "OP_UNKNOWN179", 1, opcodeInvalid},
OpUnknown180: {OpUnknown190, "OP_UNKNOWN180", 1, opcodeInvalid},
OpUnknown181: {OpUnknown191, "OP_UNKNOWN181", 1, opcodeInvalid},
OpUnknown182: {OpUnknown192, "OP_UNKNOWN182", 1, opcodeInvalid},
OpUnknown183: {OpUnknown193, "OP_UNKNOWN183", 1, opcodeInvalid},
OpUnknown184: {OpUnknown194, "OP_UNKNOWN184", 1, opcodeInvalid},
OpUnknown185: {OpUnknown195, "OP_UNKNOWN185", 1, opcodeInvalid},
OpUnknown186: {OpUnknown196, "OP_UNKNOWN186", 1, opcodeInvalid},
OpUnknown187: {OpUnknown197, "OP_UNKNOWN187", 1, opcodeInvalid},
OpUnknown188: {OpUnknown188, "OP_UNKNOWN188", 1, opcodeInvalid},
OpUnknown189: {OpUnknown189, "OP_UNKNOWN189", 1, opcodeInvalid},
OpUnknown190: {OpUnknown190, "OP_UNKNOWN190", 1, opcodeInvalid},
OpUnknown191: {OpUnknown191, "OP_UNKNOWN191", 1, opcodeInvalid},
OpUnknown192: {OpUnknown192, "OP_UNKNOWN192", 1, opcodeInvalid},
OpUnknown193: {OpUnknown193, "OP_UNKNOWN193", 1, opcodeInvalid},
OpUnknown194: {OpUnknown194, "OP_UNKNOWN194", 1, opcodeInvalid},
OpUnknown195: {OpUnknown195, "OP_UNKNOWN195", 1, opcodeInvalid},
OpUnknown196: {OpUnknown196, "OP_UNKNOWN196", 1, opcodeInvalid},
OpUnknown197: {OpUnknown197, "OP_UNKNOWN197", 1, opcodeInvalid},
OpUnknown198: {OpUnknown198, "OP_UNKNOWN198", 1, opcodeInvalid},
OpUnknown199: {OpUnknown199, "OP_UNKNOWN199", 1, opcodeInvalid},
OpUnknown200: {OpUnknown200, "OP_UNKNOWN200", 1, opcodeInvalid},
OpUnknown201: {OpUnknown201, "OP_UNKNOWN201", 1, opcodeInvalid},
OpUnknown202: {OpUnknown202, "OP_UNKNOWN202", 1, opcodeInvalid},
OpUnknown203: {OpUnknown203, "OP_UNKNOWN203", 1, opcodeInvalid},
OpUnknown204: {OpUnknown204, "OP_UNKNOWN204", 1, opcodeInvalid},
OpUnknown205: {OpUnknown205, "OP_UNKNOWN205", 1, opcodeInvalid},
OpUnknown206: {OpUnknown206, "OP_UNKNOWN206", 1, opcodeInvalid},
OpUnknown207: {OpUnknown207, "OP_UNKNOWN207", 1, opcodeInvalid},
OpUnknown208: {OpUnknown208, "OP_UNKNOWN208", 1, opcodeInvalid},
OpUnknown209: {OpUnknown209, "OP_UNKNOWN209", 1, opcodeInvalid},
OpUnknown210: {OpUnknown210, "OP_UNKNOWN210", 1, opcodeInvalid},
OpUnknown211: {OpUnknown211, "OP_UNKNOWN211", 1, opcodeInvalid},
OpUnknown212: {OpUnknown212, "OP_UNKNOWN212", 1, opcodeInvalid},
OpUnknown213: {OpUnknown213, "OP_UNKNOWN213", 1, opcodeInvalid},
OpUnknown214: {OpUnknown214, "OP_UNKNOWN214", 1, opcodeInvalid},
OpUnknown215: {OpUnknown215, "OP_UNKNOWN215", 1, opcodeInvalid},
OpUnknown216: {OpUnknown216, "OP_UNKNOWN216", 1, opcodeInvalid},
OpUnknown217: {OpUnknown217, "OP_UNKNOWN217", 1, opcodeInvalid},
OpUnknown218: {OpUnknown218, "OP_UNKNOWN218", 1, opcodeInvalid},
OpUnknown219: {OpUnknown219, "OP_UNKNOWN219", 1, opcodeInvalid},
OpUnknown220: {OpUnknown220, "OP_UNKNOWN220", 1, opcodeInvalid},
OpUnknown221: {OpUnknown221, "OP_UNKNOWN221", 1, opcodeInvalid},
OpUnknown222: {OpUnknown222, "OP_UNKNOWN222", 1, opcodeInvalid},
OpUnknown223: {OpUnknown223, "OP_UNKNOWN223", 1, opcodeInvalid},
OpUnknown224: {OpUnknown224, "OP_UNKNOWN224", 1, opcodeInvalid},
OpUnknown225: {OpUnknown225, "OP_UNKNOWN225", 1, opcodeInvalid},
OpUnknown226: {OpUnknown226, "OP_UNKNOWN226", 1, opcodeInvalid},
OpUnknown227: {OpUnknown227, "OP_UNKNOWN227", 1, opcodeInvalid},
OpUnknown228: {OpUnknown228, "OP_UNKNOWN228", 1, opcodeInvalid},
OpUnknown229: {OpUnknown229, "OP_UNKNOWN229", 1, opcodeInvalid},
OpUnknown230: {OpUnknown230, "OP_UNKNOWN230", 1, opcodeInvalid},
OpUnknown231: {OpUnknown231, "OP_UNKNOWN231", 1, opcodeInvalid},
OpUnknown232: {OpUnknown232, "OP_UNKNOWN232", 1, opcodeInvalid},
OpUnknown233: {OpUnknown233, "OP_UNKNOWN233", 1, opcodeInvalid},
OpUnknown234: {OpUnknown234, "OP_UNKNOWN234", 1, opcodeInvalid},
OpUnknown235: {OpUnknown235, "OP_UNKNOWN235", 1, opcodeInvalid},
OpUnknown236: {OpUnknown236, "OP_UNKNOWN236", 1, opcodeInvalid},
OpUnknown237: {OpUnknown237, "OP_UNKNOWN237", 1, opcodeInvalid},
OpUnknown238: {OpUnknown238, "OP_UNKNOWN238", 1, opcodeInvalid},
OpUnknown239: {OpUnknown239, "OP_UNKNOWN239", 1, opcodeInvalid},
OpUnknown240: {OpUnknown240, "OP_UNKNOWN240", 1, opcodeInvalid},
OpUnknown241: {OpUnknown241, "OP_UNKNOWN241", 1, opcodeInvalid},
OpUnknown242: {OpUnknown242, "OP_UNKNOWN242", 1, opcodeInvalid},
OpUnknown243: {OpUnknown243, "OP_UNKNOWN243", 1, opcodeInvalid},
OpUnknown244: {OpUnknown244, "OP_UNKNOWN244", 1, opcodeInvalid},
OpUnknown245: {OpUnknown245, "OP_UNKNOWN245", 1, opcodeInvalid},
OpUnknown246: {OpUnknown246, "OP_UNKNOWN246", 1, opcodeInvalid},
OpUnknown247: {OpUnknown247, "OP_UNKNOWN247", 1, opcodeInvalid},
OpUnknown248: {OpUnknown248, "OP_UNKNOWN248", 1, opcodeInvalid},
OpUnknown249: {OpUnknown249, "OP_UNKNOWN249", 1, opcodeInvalid},
OpSmallInteger: {OpSmallInteger, "OP_SMALLINTEGER", 1, opcodeInvalid},
OpPubKeys: {OpPubKeys, "OP_PUBKEYS", 1, opcodeInvalid},
OpUnknown252: {OpUnknown252, "OP_UNKNOWN252", 1, opcodeInvalid},
OpPubKeyHash: {OpPubKeyHash, "OP_PUBKEYHASH", 1, opcodeInvalid},
OpPubKey: {OpPubKey, "OP_PUBKEY", 1, opcodeInvalid},
OpInvalidOpCode: {OpInvalidOpCode, "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",
}
// parsedOpcode represents an opcode that has been parsed and includes any
// potential data associated with it.
type parsedOpcode struct {
opcode *opcode
data []byte
}
// isDisabled returns whether or not the opcode is disabled and thus is always
// bad to see in the instruction stream (even if turned off by a conditional).
func (pop *parsedOpcode) isDisabled() bool {
switch pop.opcode.value {
case OpCat:
return true
case OpSubStr:
return true
case OpLeft:
return true
case OpRight:
return true
case OpInvert:
return true
case OpAnd:
return true
case OpOr:
return true
case OpXor:
return true
case Op2Mul:
return true
case Op2Div:
return true
case OpMul:
return true
case OpDiv:
return true
case OpMod:
return true
case OpLShift:
return true
case OpRShift:
return true
default:
return false
}
}
// alwaysIllegal returns whether or not the opcode is always illegal when passed
// over by the program counter even if in a non-executed branch (it isn't a
// coincidence that they are conditionals).
func (pop *parsedOpcode) alwaysIllegal() bool {
switch pop.opcode.value {
case OpVerIf:
return true
case OpVerNotIf:
return true
default:
return false
}
}
// isConditional returns whether or not the opcode is a conditional opcode which
// changes the conditional execution stack when executed.
func (pop *parsedOpcode) isConditional() bool {
switch pop.opcode.value {
case OpIf:
return true
case OpNotIf:
return true
case OpElse:
return true
case OpEndIf:
return true
default:
return false
}
}
// checkMinimalDataPush returns whether or not the current data push uses the
// smallest possible opcode to represent it. For example, the value 15 could
// be pushed with OP_DATA_1 15 (among other variations); however, OP_15 is a
// single opcode that represents the same value and is only a single byte versus
// two bytes.
func (pop *parsedOpcode) checkMinimalDataPush() error {
data := pop.data
dataLen := len(data)
opcode := pop.opcode.value
if dataLen == 0 && opcode != Op0 {
str := fmt.Sprintf("zero length data push is encoded with "+
"opcode %s instead of OP_0", pop.opcode.name)
return scriptError(ErrMinimalData, str)
} else if dataLen == 1 && data[0] >= 1 && data[0] <= 16 {
if opcode != Op1+data[0]-1 {
// Should have used OP_1 .. OP_16
str := fmt.Sprintf("data push of the value %d encoded "+
"with opcode %s instead of OP_%d", data[0],
pop.opcode.name, data[0])
return scriptError(ErrMinimalData, str)
}
} else if dataLen == 1 && data[0] == 0x81 {
if opcode != Op1Negate {
str := fmt.Sprintf("data push of the value -1 encoded "+
"with opcode %s instead of OP_1NEGATE",
pop.opcode.name)
return scriptError(ErrMinimalData, str)
}
} else if dataLen <= 75 {
if int(opcode) != dataLen {
// Should have used a direct push
str := fmt.Sprintf("data push of %d bytes encoded "+
"with opcode %s instead of OP_DATA_%d", dataLen,
pop.opcode.name, dataLen)
return scriptError(ErrMinimalData, str)
}
} else if dataLen <= 255 {
if opcode != OpPushData1 {
str := fmt.Sprintf("data push of %d bytes encoded "+
"with opcode %s instead of OP_PUSHDATA1",
dataLen, pop.opcode.name)
return scriptError(ErrMinimalData, str)
}
} else if dataLen <= 65535 {
if opcode != OpPushData2 {
str := fmt.Sprintf("data push of %d bytes encoded "+
"with opcode %s instead of OP_PUSHDATA2",
dataLen, pop.opcode.name)
return scriptError(ErrMinimalData, str)
}
}
return nil
}
// print returns a human-readable string representation of the opcode for use
// in script disassembly.
func (pop *parsedOpcode) print(oneline bool) string {
// The reference implementation one-line disassembly replaces opcodes
// which represent values (e.g. OP_0 through OP_16 and OP_1NEGATE)
// with the raw value. However, when not doing a one-line dissassembly,
// we prefer to show the actual opcode names. Thus, only replace the
// opcodes in question when the oneline flag is set.
opcodeName := pop.opcode.name
if oneline {
if replName, ok := opcodeOnelineRepls[opcodeName]; ok {
opcodeName = replName
}
// Nothing more to do for non-data push opcodes.
if pop.opcode.length == 1 {
return opcodeName
}
return fmt.Sprintf("%x", pop.data)
}
// Nothing more to do for non-data push opcodes.
if pop.opcode.length == 1 {
return opcodeName
}
// Add length for the OP_PUSHDATA# opcodes.
retString := opcodeName
switch pop.opcode.length {
case -1:
retString += fmt.Sprintf(" 0x%02x", len(pop.data))
case -2:
retString += fmt.Sprintf(" 0x%04x", len(pop.data))
case -4:
retString += fmt.Sprintf(" 0x%08x", len(pop.data))
}
return fmt.Sprintf("%s 0x%02x", retString, pop.data)
}
// bytes returns any data associated with the opcode encoded as it would be in
// a script. This is used for unparsing scripts from parsed opcodes.
func (pop *parsedOpcode) bytes() ([]byte, error) {
var retbytes []byte
if pop.opcode.length > 0 {
retbytes = make([]byte, 1, pop.opcode.length)
} else {
retbytes = make([]byte, 1, 1+len(pop.data)-
pop.opcode.length)
}
retbytes[0] = pop.opcode.value
if pop.opcode.length == 1 {
if len(pop.data) != 0 {
str := fmt.Sprintf("internal consistency error - "+
"parsed opcode %s has data length %d when %d "+
"was expected", pop.opcode.name, len(pop.data),
0)
return nil, scriptError(ErrInternal, str)
}
return retbytes, nil
}
nbytes := pop.opcode.length
if pop.opcode.length < 0 {
l := len(pop.data)
// tempting just to hardcode to avoid the complexity here.
switch pop.opcode.length {
case -1:
retbytes = append(retbytes, byte(l))
nbytes = int(retbytes[1]) + len(retbytes)
case -2:
retbytes = append(retbytes, byte(l&0xff),
byte(l>>8&0xff))
nbytes = int(binary.LittleEndian.Uint16(retbytes[1:])) +
len(retbytes)
case -4:
retbytes = append(retbytes, byte(l&0xff),
byte((l>>8)&0xff), byte((l>>16)&0xff),
byte((l>>24)&0xff))
nbytes = int(binary.LittleEndian.Uint32(retbytes[1:])) +
len(retbytes)
}
}
retbytes = append(retbytes, pop.data...)
if len(retbytes) != nbytes {
str := fmt.Sprintf("internal consistency error - "+
"parsed opcode %s has data length %d when %d was "+
"expected", pop.opcode.name, len(retbytes), nbytes)
return nil, scriptError(ErrInternal, str)
}
return retbytes, nil
}
// *******************************************
// 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 *parsedOpcode, vm *Engine) error {
str := fmt.Sprintf("attempt to execute disabled opcode %s",
op.opcode.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 *parsedOpcode, vm *Engine) error {
str := fmt.Sprintf("attempt to execute reserved opcode %s",
op.opcode.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 *parsedOpcode, vm *Engine) error {
str := fmt.Sprintf("attempt to execute invalid opcode %s",
op.opcode.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 *parsedOpcode, 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 *parsedOpcode, vm *Engine) error {
vm.dstack.PushByteArray(op.data)
return nil
}
// opcode1Negate pushes -1, encoded as a number, to the data stack.
func opcode1Negate(op *parsedOpcode, 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 *parsedOpcode, vm *Engine) error {
// The opcodes are all defined consecutively, so the numeric value is
// the difference.
vm.dstack.PushInt(scriptNum((op.opcode.value - (Op1 - 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 *parsedOpcode, vm *Engine) error {
return nil
}
// popIfBool enforces the "minimal if" policy. In order to
// eliminate an additional source of nuisance malleability, we
// require the following: for OP_IF and OP_NOTIF, the top stack item MUST
// either be an empty byte slice, or [0x01]. Otherwise, the item at the top of
// the stack will be popped and interpreted as a boolean.
func popIfBool(vm *Engine) (bool, error) {
so, err := vm.dstack.PopByteArray()
if err != nil {
return false, err
}
if len(so) == 1 && so[0] == 0x01 {
return true, nil
}
if len(so) == 0 {
return false, nil
}
str := fmt.Sprintf("with OP_IF or OP_NOTIF top stack item MUST "+
"be an empty byte array or 0x01, and is instead: %x",
so)
return false, scriptError(ErrMinimalIf, str)
}
// 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] -> [...]
// Conditional stack transformation: [...] -> [... OpCondValue]
func opcodeIf(op *parsedOpcode, vm *Engine) error {
condVal := OpCondFalse
if vm.isBranchExecuting() {
ok, err := popIfBool(vm)
if err != nil {
return err
}
if ok {
condVal = OpCondTrue
}
} else {
condVal = OpCondSkip
}
vm.condStack = append(vm.condStack, condVal)
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] -> [...]
// Conditional stack transformation: [...] -> [... OpCondValue]
func opcodeNotIf(op *parsedOpcode, vm *Engine) error {
condVal := OpCondFalse
if vm.isBranchExecuting() {
ok, err := popIfBool(vm)
if err != nil {
return err
}
if !ok {
condVal = OpCondTrue
}
} else {
condVal = OpCondSkip
}
vm.condStack = append(vm.condStack, condVal)
return nil
}
// opcodeElse inverts conditional execution for other half of if/else/endif.
//