constants

README

constants

Bitcoin network constants and magic numbers, implemented as golang structs.

Documentation

Overview

Package constants provides magic numbers and other useful data, such as opcodes, which would otherwise have to be copy/pasted and re-declared across packages.

Index

• Constants
• Variables
• type AddressFormat
• type Network

Constants

const (
	// BitcoinSeedIV is the initialization vector used for creating bitcoin wallet seeds.
	BitcoinSeedIV = "Bitcoin seed"

	// Base58Alphabet is the Bitcoin Base 58 alphabet.
	Base58Alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"

	// Bech32Alphabet is the base-32 encoding alphabet for BECH32 as specified in BIP-173.
	Bech32Alphabet = "qpzry9x8gf2tvdw0s3jn54khce6mua7l"

	// Bech32Separator is the separating character in bech32 which separates the HRP from the version number and encoded data.
	Bech32Separator = "1"

	// Bip32Hardened is the HD key index threshold above which any derived child keys are hardened.
	Bip32Hardened uint32 = 0x80000000

	// BlockMaxSize is the maximum block size, not including segwit data.
	BlockMaxSize = 1000000

	// OpReturnMaxSize is the maximum size of an OP_RETURN output data payload.
	OpReturnMaxSize = 80

	// SatoshisPerBitcoin is the number of base satoshi units per BTC
	SatoshisPerBitcoin = 100_000_000

	// SeedMinimumSize and SeedMaximumSize are the lower and upper limits on
	// the byte-size of a BIP39 seed which can be used for generating a master key.
	SeedMinimumSize int = 128 / 8
	SeedMaximumSize int = 512 / 8

	// SerializedExtendedKeyLength is the byte length of a bip32 serialized extended key.
	SerializedExtendedKeyLength int = 78

	// SigHash enum types
	SigHashAll          uint32 = 1
	SigHashNone         uint32 = 2
	SigHashSingle       uint32 = 3
	SigHashAnyoneCanPay uint32 = 0x80

	// PublicKeyCompressedLength is the byte-size of a compressed public key.
	PublicKeyCompressedLength int = 33
	// PublicKeyUncompressedLength is the byte-size of an uncompressed public key.
	PublicKeyUncompressedLength int = 65
	// PublicKeySchnorrLength is the byte-size of a BIP340 schnorr public key.
	PublicKeySchnorrLength int = 32

	// PublicKeyCompressedEvenByte and PublicKeyCompressedOddByte indicate the bytes prefixing
	// compressed public keys to indicate whether the Y coordinate of the public key point (X, Y) is even or odd.
	PublicKeyCompressedEvenByte byte = 2
	PublicKeyCompressedOddByte  byte = 3
	PublicKeyUncompressedPrefix byte = 4

	// TaprootLeafVersionTapscript is the version number used in Taproot Tapscript leaf nodes.
	TaprootLeafVersionTapscript = 0xc0

	// WitnessVersionZero is the first witness version introduced. It is used for bech32-encoded
	// P2WPKH and P2WSH witness programs.
	WitnessVersionZero = 0
)

const (
	OP_0                   = 0x00 // 0
	OP_FALSE               = 0x00 // 0 or 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 or 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 or OP_NOP2
	OP_NOP3                = 0xb2 // 178
	OP_CHECKSEQUENCEVERIFY = 0xb2 // 178 or 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_CHECKSIGADD         = 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
)

Variables

var (
	// Bech32ChecksumGen are the seed numbers used to create bech32 checksums.
	// https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki#Checksum
	Bech32ChecksumGen = [...]int{0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3}

	// TxSegwitFlag is the byte sequence which, if present in a serialized transaction at a certain
	// location, indicates the precense of witness data.
	TxSegwitFlag = [...]byte{0, 1}
)

var (
	BitcoinNetwork = Network{
		Symbol:          "BTC",
		Name:            "Bitcoin",
		Bech32:          "bc",
		ScriptHash:      5,
		PubkeyHash:      0,
		WIF:             128,
		ExtendedPublic:  76067358,
		ExtendedPrivate: 76066276,
	}

	BitcoinTestnet = Network{
		Symbol:          "tBTC",
		Name:            "Testnet Bitcoin",
		Bech32:          "tb",
		ScriptHash:      196,
		PubkeyHash:      111,
		WIF:             239,
		ExtendedPublic:  70617039,
		ExtendedPrivate: 70615956,
	}

	LitecoinNetwork = Network{
		Symbol:          "LTC",
		Name:            "Litecoin",
		Bech32:          "ltc",
		ScriptHash:      50,
		PubkeyHash:      48,
		WIF:             176,
		ExtendedPublic:  27108450,
		ExtendedPrivate: 27106558,
	}

	ZcashNetwork = Network{
		Symbol:          "ZEC",
		Name:            "Zcash",
		ScriptHash:      7357,
		PubkeyHash:      7352,
		WIF:             128,
		ExtendedPublic:  76067358,
		ExtendedPrivate: 76066276,
	}
)

var CurrentNetwork = BitcoinNetwork

CurrentNetwork is a global variable that defines which network callers should use.

var NetworksByName = map[string]Network{
	"Bitcoin":  BitcoinNetwork,
	"Litecoin": LitecoinNetwork,
	"Zcash":    ZcashNetwork,
}

NetworksByName exposes network data sorted by capitalized coin names.

var NetworksBySymbol = map[string]Network{
	"BTC": BitcoinNetwork,
	"LTC": LitecoinNetwork,
	"ZEC": ZcashNetwork,
}

NetworksBySymbol exposes network data sorted by coin ticker symbol.

var OpCodes = map[string]byte{}/* 260 elements not displayed */

OpCodes is a map of human-readable opcode names to opcode byte values.

Types

type AddressFormat

type AddressFormat string

AddressFormat is used to describe different standardized script pubkey formats.

const (
	FormatP2PKH       AddressFormat = "P2PKH"
	FormatP2SH        AddressFormat = "P2SH"
	FormatP2WPKH      AddressFormat = "P2WPKH"
	FormatP2WSH       AddressFormat = "P2WSH"
	FormatNONSTANDARD AddressFormat = "NONSTANDARD"
)

type Network

type Network struct {
	// The ticker symbol and name of this coin's network.
	Symbol string
	Name   string

	// Only availble for segwit-enabled coins.
	Bech32 string

	// Constants used for base58-check encoding of addresses.
	ScriptHash uint16
	PubkeyHash uint16

	// Used for base58-check encoding of WIF private keys.
	WIF byte

	// Used for base58-check encoding of extended public and private keys.
	ExtendedPublic  uint32
	ExtendedPrivate uint32
}

Network represents a bitcoin-like coin, housing all the special magic numbers which are used for encoding addresses, and public and private keys.