NAME
Bitcoin::Crypto::Constants - Bitcoin-related constant values
SYNOPSIS
use Bitcoin::Crypto::Constants (
# these constants are grouped under :curve tag
'CURVE_NAME',
'CURVE_ORDER',
'CURVE_GENERATOR',
# these constants are grouped under :key tag
'MAX_CHILD_KEYS',
'KEY_MAX_LENGTH',
'WIF_COMPRESSED_BYTE',
# these constants are grouped under :witness tag
'SEGWIT_WITNESS_VERSION',
'TAPROOT_WITNESS_VERSION',
'MAX_WITNESS_VERSION',
# these constants are grouped under :bip44 tag
'BIP44_PURPOSE',
'BIP44_COMPAT_PURPOSE',
'BIP44_SEGWIT_PURPOSE',
'BIP44_TAPROOT_PURPOSE',
# these constants are grouped under :coin tag
'UNITS_PER_COIN',
'MAX_MONEY',
# these constants are grouped under :transaction tag
'LOCKTIME_HEIGHT_THRESHOLD',
'MAX_SEQUENCE_NO',
'RBF_SEQUENCE_NO_THRESHOLD',
'NULL_UTXO',
# these constants are grouped under :sighash tag
'SIGHASH_DEFAULT',
'SIGHASH_ALL',
'SIGHASH_NONE',
'SIGHASH_SINGLE',
'SIGHASH_ANYONECANPAY',
# these constants are grouped under :script tag
'SCRIPT_MAX_STACK_ELEMENTS',
'SCRIPT_MAX_ELEMENT_SIZE',
'SCRIPT_MAX_OPCODES',
'SCRIPT_MAX_SIZE',
'SCRIPT_MAX_MULTISIG_PUBKEYS',
'TAPSCRIPT_LEAF_VERSION',
# these constants are grouped under :psbt tag
'PSBT_MAGIC',
'PSBT_SEPARATOR',
'PSBT_GLOBAL_MAP',
'PSBT_INPUT_MAP',
'PSBT_OUTPUT_MAP',
# these constants are grouped under :bech32 tag
'BECH32',
'BECH32M',
# these constants are ungrouped
'USE_BIGINTS',
);
# or, if you are not sure...
use Bitcoin::Crypto::Constants qw(:all);DESCRIPTION
This package contains named constants for all kinds of values used across Bitcoin. It is not uncommon to have a need to use these values in code which interacts with Bitcoin::Crypto.
Each constant can be accessed either by importing it (as shown above) or by calling a fully qualified name, like Bitcoin::Crypto::Constants::MAX_MONEY. For backward compatibility, the second form can also be used with lowercase name: Bitcoin::Crypto::Constants::max_money.
To avoid overly long import statements, constants are organized under tags. Unless there is a reason not to, it is recommended to import tags instead of each constant separately. The exception is the :all tag, which should be used sparingly.
TAGS
:all
Imports everything. Should generally be avoided to not clutter the namespace.
:curve
Contains basic secp256k1 curve data:
"CURVE_NAME", "CURVE_ORDER", "CURVE_GENERATOR"
:key
Contains values which may be required when dealing with keys:
"MAX_CHILD_KEYS", "KEY_MAX_LENGTH", "WIF_COMPRESSED_BYTE"
:witness
Contains values for witness versions:
"SEGWIT_WITNESS_VERSION", "TAPROOT_WITNESS_VERSION", "MAX_WITNESS_VERSION"
:bip44
Contains various BIP44 purpose values:
"BIP44_PURPOSE", "BIP44_COMPAT_PURPOSE", "BIP44_SEGWIT_PURPOSE", "BIP44_TAPROOT_PURPOSE"
:coin
Contains very basic coin constants:
:transaction
Contains constants used together with transactions:
"LOCKTIME_HEIGHT_THRESHOLD", "MAX_SEQUENCE_NO", "RBF_SEQUENCE_NO_THRESHOLD", "NULL_UTXO"
:sighash
Contains known sighash values:
"SIGHASH_DEFAULT", "SIGHASH_ALL", "SIGHASH_NONE", "SIGHASH_SINGLE", "SIGHASH_ANYONECANPAY"
:script
Contains values used during script creation and execution:
"SCRIPT_MAX_STACK_ELEMENTS", "SCRIPT_MAX_ELEMENT_SIZE", "SCRIPT_MAX_OPCODES", "SCRIPT_MAX_SIZE", "SCRIPT_MAX_MULTISIG_PUBKEYS", "TAPSCRIPT_LEAF_VERSION"
:psbt
Contains values useful for PSBTs:
"PSBT_MAGIC", "PSBT_SEPARATOR", "PSBT_GLOBAL_MAP", "PSBT_INPUT_MAP", "PSBT_OUTPUT_MAP"
:bech32
Contains values useful for BECH32:
CONSTANTS
CURVE_NAME
Curve name used by Bitcoin, secp256k1
CURVE_ORDER
A bytestring containing the secp256k1 curve order.
CURVE_GENERATOR
A bytestring with serialized uncompressed curve generator point for secp256k1.
MAX_CHILD_KEYS
Maximum number of keys which can be derived in extended key derivation. Values above it start being recognized as hardened instead, and start counting from 0.
KEY_MAX_LENGTH
The maximum byte length of a serialized private key.
WIF_COMPRESSED_BYTE
A magic byte which is used in WIFs to mark the key as compressed.
SEGWIT_WITNESS_VERSION
Numeric witness version used in SegWit (version 0) programs.
TAPROOT_WITNESS_VERSION
Numeric witness version used in Taproot (version 1) programs.
MAX_WITNESS_VERSION
Numeric maximum possible witness version.
BIP44_PURPOSE
Numeric base BIP44 purpose.
BIP44_COMPAT_PURPOSE
Numeric BIP44 compat SegWit purpose (BIP49)
BIP44_SEGWIT_PURPOSE
Numeric BIP44 native SegWit purpose (BIP84)
BIP44_TAPROOT_PURPOSE
Numeric BIP44 native SegWit purpose (BIP86)
UNITS_PER_COIN
Number of satoshis that equal a single coin.
MAX_MONEY
Number of satoshis that will ever exist.
LOCKTIME_HEIGHT_THRESHOLD
First number which will be understood as timestamp in locktime checks.
MAX_SEQUENCE_NO
Default and maximum possible "sequence_no" in Bitcoin::Crypto::Transaction::Input.
RBF_SEQUENCE_NO_THRESHOLD
Value which is used in finding out if a transaction has Replace-By-Fee enabled.
NULL_UTXO
An 2-element array reference which is an UTXO location for a coinbase transaction.
SIGHASH_DEFAULT
Default hashtype for digests - only used in Taproot. Functionally equal to SIGHASH_ALL.
SIGHASH_ALL
Hashtype for digesting all outputs of a transaction - default in pre-Taproot.
SIGHASH_NONE
Hashtype for digesting no transaction outputs.
SIGHASH_SINGLE
Hashtype for digesting only one output in a transaction, corresponding to this input.
SIGHASH_ANYONECANPAY
Hashtype for digesting only this input and no other inputs. Cannot be used standalone, must be binary-or'ed with other SIGHASH constants.
SCRIPT_MAX_STACK_ELEMENTS
Maximum number of elements which can be kept on a script stack and altstack together.
SCRIPT_MAX_ELEMENT_SIZE
Maximum byte size of a single stack element.
SCRIPT_MAX_OPCODES
Maximum non-push opcodes which can be used in a single script. Not applicable to Taproot.
SCRIPT_MAX_SIZE
Maximum script size in bytes. Not applicable to Taproot.
SCRIPT_MAX_MULTISIG_PUBKEYS
Maximum OP_CHECKMULTISIG public keys.
TAPSCRIPT_LEAF_VERSION
Tree leaf version number used in Taproot tapscript spends.
PSBT_MAGIC
A magic byte sequence which is required in PSBTs.
PSBT_SEPARATOR
A byte sequence which separates PSBT maps.
PSBT_GLOBAL_MAP
A value for making use of global PSBT maps.
PSBT_INPUT_MAP
A value for making use of input PSBT maps.
PSBT_OUTPUT_MAP
A value for making use of output PSBT maps.
BECH32
A value used for marking original bech32 serialization
BECH32M
A value used for marking bech32m serialization
USE_BIGINTS
Whether the module currently uses BigInts (32-bit architecture compatibility). Can be forced to a true value by setting BITCOIN_CRYPTO_USE_BIGINTS environmental variable.