Documentation
¶
Index ¶
- Constants
- func CheckMinimalDataEncoding(bytes []byte) error
- type ParsedOpCode
- type ScriptBuilder
- type ScriptFlags
- type ScriptNum
- type SignHash
- type Stack
- func (stack *Stack) Depth() int32
- func (stack *Stack) DropN(n int32) error
- func (stack *Stack) DuplicateN(n int32) error
- func (stack *Stack) NipN(idx int32) error
- func (stack *Stack) OverN(n int32) error
- func (stack *Stack) PeekBool(idx int32) (bool, error)
- func (stack *Stack) PeekByteArray(idx int32) ([]byte, error)
- func (stack *Stack) PeekInt(idx int32) (ScriptNum, error)
- func (stack *Stack) PickN(n int32) error
- func (stack *Stack) PopBool() (bool, error)
- func (stack *Stack) PopByteArray() ([]byte, error)
- func (stack *Stack) PopInt() (ScriptNum, error)
- func (stack *Stack) PushBool(val bool)
- func (stack *Stack) PushBytes(bytes []byte)
- func (stack *Stack) PushInt(scriptNum ScriptNum)
- func (stack *Stack) RollN(n int32) error
- func (stack *Stack) RotateN(n int32) error
- func (stack *Stack) String() string
- func (stack *Stack) SwapN(n int32) error
- func (stack *Stack) Tuck() error
Constants ¶
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_RESERVED1 = 0x89 // 137 OP_RESERVED2 = 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_SHA256 = 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_UNKNOWN186 = 0xba // 186 OP_UNKNOWN187 = 0xbb // 187 OP_UNKNOWN188 = 0xbc // 188 OP_UNKNOWN189 = 0xbd // 189 OP_UNKNOWN190 = 0xbe // 190 OP_UNKNOWN191 = 0xbf // 191 OP_UNKNOWN192 = 0xc0 // 192 OP_UNKNOWN193 = 0xc1 // 193 OP_UNKNOWN194 = 0xc2 // 194 OP_UNKNOWN195 = 0xc3 // 195 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_UNKNOWN249 = 0xf9 // 249 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 )
const ( OpCondFalse = 0 OpCondTrue = 1 OpCondSkip = 2 )
Conditional execution constants.
const ( MaxInt32 = 1<<31 - 1 MinInt32 = -1 << 31 DefaultScriptNumLen = 4 )
Variables ¶
This section is empty.
Functions ¶
Types ¶
type ParsedOpCode ¶
type ParsedOpCode struct {
// contains filtered or unexported fields
}
type ScriptBuilder ¶
type ScriptBuilder struct {
// contains filtered or unexported fields
}
type ScriptFlags ¶
type ScriptFlags uint32
const ( ScriptBip16 ScriptFlags = 1 << iota ScriptStrictMultiSig ScriptDiscourageUpgradeableNops ScriptVerifyCheckLockTimeVerify // ScriptVerifyCheckSequenceVerify defines whether to allow execution // pathways of a script to be restricted based on the age of the output // being spent. This is BIP0112. ScriptVerifyCheckSequenceVerify // ScriptVerifyCleanStack defines that the stack must contain only // one stack element after evaluation and that the element must be // true if interpreted as a boolean. This is rule 6 of BIP0062. // This flag should never be used without the ScriptBip16 flag. ScriptVerifyCleanStack // ScriptVerifyDERSignatures defines that signatures are required // to compily with the DER format. ScriptVerifyDERSignatures // ScriptVerifyLowS defines that signtures are required to comply with // the DER format and whose S value is <= order / 2. This is rule 5 // of BIP0062. ScriptVerifyLowS // ScriptVerifyMinimalData defines that signatures must use the smallest // push operator. This is both rules 3 and 4 of BIP0062. ScriptVerifyMinimalData // ScriptVerifyNullFail defines that signatures must be empty if // a CHECKSIG or CHECKMULTISIG operation fails. ScriptVerifyNullFail // ScriptVerifySigPushOnly defines that signature scripts must contain // only pushed data. This is rule 2 of BIP0062. ScriptVerifySigPushOnly // ScriptVerifyStrictEncoding defines that signature scripts and // public keys must follow the strict encoding requirements. ScriptVerifyStrictEncoding )
type ScriptNum ¶
type ScriptNum int64
ScriptNum represents a numeric value used in the scripting engine with special handling to deal with the subtle semantics required by consensus.
All numbers are stored on the data and alternate stacks encoded as little endian with a sign bit. All numeric opcodes such as OP_ADD, OP_SUB, and OP_MUL, are only allowed to operate on 4-byte integers in the range [-2^31 + 1, 2^31 - 1], however the results of numeric operations may overflow and remain valid so long as they are not used as inputs to other numeric operations or otherwise interpreted as an integer.
For example, it is possible for OP_ADD to have 2^31 - 1 for its two operands resulting 2^32 - 2, which overflows, but is still pushed to the stack as the result of the addition. That value can then be used as input to OP_VERIFY which will succeed because the data is being interpreted as a boolean. However, if that same value were to be used as input to another numeric opcode, such as OP_SUB, it must fail.
This type handles the aforementioned requirements by storing all numeric operation results as an int64 to handle overflow and provides the Bytes method to get the serialized representation (including values that overflow).
Then, whenever data is interpreted as an integer, it is converted to this type by using the makeScriptNum function which will return an error if the number is out of range or not minimally encoded depending on parameters. Since all numeric opcodes involve pulling data from the stack and interpreting it as an integer, it provides the required behavior.
func (ScriptNum) Bytes ¶
Bytes returns the number serialized as a little endian with a sign bit.
Example encodings:
127 -> [0x7f] -127 -> [0xff] 128 -> [0x80 0x00] -128 -> [0x80 0x80] 129 -> [0x81 0x00] -129 -> [0x81 0x80] 256 -> [0x00 0x01] -256 -> [0x00 0x81] 32767 -> [0xff 0x7f] -32767 -> [0xff 0xff] 32768 -> [0x00 0x80 0x00] -32768 -> [0x00 0x80 0x80]
func (ScriptNum) Int32 ¶
Int32 returns the script number clamped to a valid int32. That is to say when the script number is higher than the max allowed int32, the max int32 value is returned and vice versa for the minimum value. Note that this behavior is different from a simple int32 cast because that truncates and the consensus rules dictate numbers which are directly cast to ints provide this behavior.
In practice, for most opcodes, the number should never be out of range since it will have been created with makeScriptNum using the defaultScriptLen value, which rejects them. In case something in the future ends up calling this function against the result of some arithmetic, which IS allowed to be out of range before being reinterpreted as an integer, this will provide the correct behavior.
type Stack ¶
type Stack struct {
// contains filtered or unexported fields
}
func (*Stack) DropN ¶
DropN removes the top N items from the stack.
Stack transformation: DropN(1): [... x1 x2] -> [... x1] DropN(2): [... x1 x2] -> [...]
func (*Stack) DuplicateN ¶
DuplicateN duplicates the top N items on the stack.
Stack transformation: DupN(1): [... x1 x2] -> [... x1 x2 x2] DupN(2): [... x1 x2] -> [... x1 x2 x1 x2]
func (*Stack) OverN ¶
OverN copies N items N items back to the top of the stack.
Stack transformation: OverN(1): [... x1 x2 x3] -> [... x1 x2 x3 x2] OverN(2): [... x1 x2 x3 x4] -> [... x1 x2 x3 x4 x1 x2]
func (*Stack) PeekByteArray ¶
PeekByteArray returns the Nth item on the stack without removing it.
func (*Stack) PickN ¶
PickN copies the item N items back in the stack to the top.
Stack transformation: PickN(0): [x1 x2 x3] -> [x1 x2 x3 x3] PickN(1): [x1 x2 x3] -> [x1 x2 x3 x2] PickN(2): [x1 x2 x3] -> [x1 x2 x3 x1]
func (*Stack) PopBool ¶
PopBool pops the value off the top of the stack, converts it into a bool, and returns it.
Stack transformation: [... x1 x2 x3] -> [... x1 x2]
func (*Stack) PopByteArray ¶
func (*Stack) PopInt ¶
PopInt pops the value off the top of the stack, converts it into a script num, and returns it. The act of converting to a script num enforces the consensus rules imposed on data interpreted as numbers.
Stack transformation: [... x1 x2 x3] -> [... x1 x2]
func (*Stack) RollN ¶
RollN moves the item N items back in the stack to the top.
Stack transformation: RollN(0): [x1 x2 x3] -> [x1 x2 x3] RollN(1): [x1 x2 x3] -> [x1 x3 x2] RollN(2): [x1 x2 x3] -> [x2 x3 x1]
Source Files