NAME

Bitcoin::Crypto::BIP85 - BIP85 (deterministic entropy) implementation

SYNOPSIS

use Bitcoin::Crypto::BIP85;

my $bip85 = Bitcoin::Crypto::BIP85->new(
	key => $extended_private_key,
);

# get raw bytestring seed
my $seed = $bip85->derive_entropy("m/0'/0'");

# get a mnemonic
my $mnemonic = $bip85->derive_mnemonic(index => 0);

DESCRIPTION

This module implements BIP85, enabling deterministic entropy generation from a master key.

It currently implements the following applications from the BIP85 spec:

Missing BIP85 applications can be implemented using "derive_entropy" with proper derivation path and entropy length.

INTERFACE

Attributes

key

Required in the constructor. The master key from which the generation will be performed, an instance of Bitcoin::Crypto::Key::ExtPrivate.

Methods

new

$bip_object = $class->new(%data)

This is a standard Moo constructor, which can be used to create the object. It takes arguments specified in "Attributes".

derive_entropy

$bytestr = $object->derive_entropy($path, $length = undef)

Returns entropy derived from the master key using $path, which can be a standard string derivation path like m/83696968'/0'/0' or an instance of Bitcoin::Crypto::DerivationPath. The derivation path must be fully hardened, as specified in the BIP.

Optional $length is the desired length of the entropy in bytes. If not provided, full 64 bytes of entropy will be returned. If provided and less than 64, the entropy will be truncated to the derired length. If greater than 64, the DRNG algorithm defined in BIP85 will be used to stretch the entropy to this size.

derive_mnemonic

$mnemonic = $object->derive_mnemonic(%args)

Derives mnemonic from the master key. %args can be any combination of:

  • words

    The number of words to generate. Can be either 12, 18 or 24. Default: 24.

  • language

    The language to use. See Bitcoin::BIP39 for more info about this argument. Default: en.

  • index

    The generation index. Must be a non-negative integer. Default: 0

derive_prv

$prv = $object->derive_prv(%args)

Derives private key from the master key. The key can immediately be serialized using ->to_wif to match BIP85 spec for this application. %args can be any combination of:

  • index

    The generation index. Must be a non-negative integer. Default: 0

derive_extprv

$extprv = $object->derive_extprv(%args)

Derives an extended private key from the master key. The key can immediately be serialized using ->to_serialized to match BIP85 spec for this application. %args can be any combination of:

  • index

    The generation index. Must be a non-negative integer. Default: 0

derive_bytes

$bytestr = $object->derive_bytes(%args)

Derives a number of bytes from the master key. The key can immediately be serialized as hex using "to_format" in Bitcoin::Crypto::Util to match BIP85 spec for this application. %args can be any combination of:

  • bytes

    The number of bytes to generate. Must be between 16 and 64, inclusive.

  • index

    The generation index. Must be a non-negative integer. Default: 0