Internal API Documentation¶

In addition to the public API, the classes and functions documented here are available for use within HWI itself.

Base 58 conversion utilities¶

hwilib._base58.encode(b)¶

Encode bytes to a base58-encoded string

Parameters: b (bytes) – Bytes to encode
Returns: Base58 encoded string of b
Return type: str

hwilib._base58.decode(s)¶

Decode a base58-encoding string, returning bytes

Parameters: s (str) – Base48 string to decode
Returns: Bytes encoded by s
Return type: bytes

hwilib._base58.get_xpub_fingerprint(s)¶

Get the parent fingerprint from an extended public key

Parameters: s (str) – The extended pubkey
Returns: The parent fingerprint bytes
Return type: bytes

hwilib._base58.get_xpub_fingerprint_hex(xpub)¶

Get the parent fingerprint as a hex string from an extended public key

Parameters

s – The extended pubkey
xpub (str) –

Returns

The parent fingerprint as a hex string

Return type

str

hwilib._base58.to_address(b, version)¶

Base58 Check Encode the data with the version number. Used to encode legacy style addresses.

Parameters

b (bytes) – The data to encode
version (bytes) – The version number to encode with

Returns

The Base58 Check Encoded string

Return type

str

hwilib._base58.xpub_to_pub_hex(xpub)¶

Get the public key as a string from the extended public key.

Parameters: xpub (str) – The extended pubkey
Returns: The pubkey hex string
Return type: str

hwilib._base58.xpub_main_2_test(xpub)¶

Convert an extended pubkey from mainnet version to testnet version.

Parameters: xpub (str) – The extended pubkey
Returns: The extended pubkey re-encoded using testnet version bytes
Return type: str

Bech32 Conversion Utilities¶

Reference implementation for Bech32 and segwit addresses.

hwilib._bech32.bech32_polymod(values)¶

Internal function that computes the Bech32 checksum.

Parameters: values (List[int]) –
Return type: int

hwilib._bech32.bech32_hrp_expand(hrp)¶

Expand the HRP into values for checksum computation.

Parameters: hrp (str) –
Return type: List[int]

hwilib._bech32.bech32_verify_checksum(hrp, data)¶

Verify a checksum given HRP and converted data characters.

Parameters

hrp (str) –
data (List[int]) –

Return type

bool

hwilib._bech32.bech32_create_checksum(hrp, data)¶

Compute the checksum values given HRP and data.

Parameters

hrp (str) –
data (List[int]) –

Return type

List[int]

hwilib._bech32.bech32_encode(hrp, data)¶

Compute a Bech32 string given HRP and data values.

Parameters

hrp (str) –
data (List[int]) –

Return type

str

hwilib._bech32.bech32_decode(bech)¶

Validate a Bech32 string, and determine HRP and data.

Parameters: bech (str) –
Return type: Tuple[Optional[str], Optional[List[int]]]

hwilib._bech32.convertbits(data, frombits, tobits, pad=True)¶

General power-of-2 base conversion.

Parameters

data (Union[bytes, List[int]]) –
frombits (int) –
tobits (int) –
pad (bool) –

Return type

Optional[List[int]]

hwilib._bech32.decode(hrp, addr)¶

Decode a segwit address.

Parameters

hrp (str) –
addr (str) –

Return type

Tuple[Optional[int], Optional[List[int]]]

hwilib._bech32.encode(hrp, witver, witprog)¶

Encode a segwit address.

Parameters

hrp (str) –
witver (int) –
witprog (bytes) –

Return type

Optional[str]

Bitcoin Script utilities¶

hwilib._script.is_opreturn(script)¶

Determine whether a script is an OP_RETURN output script.

Parameters: script (bytes) – The script
Returns: Whether the script is an OP_RETURN output script
Return type: bool

hwilib._script.is_p2sh(script)¶

Determine whether a script is a P2SH output script.

Parameters: script (bytes) – The script
Returns: Whether the script is a P2SH output script
Return type: bool

hwilib._script.is_p2pkh(script)¶

Determine whether a script is a P2PKH output script.

Parameters: script (bytes) – The script
Returns: Whether the script is a P2PKH output script
Return type: bool

hwilib._script.is_p2pk(script)¶

Determine whether a script is a P2PK output script.

Parameters: script (bytes) – The script
Returns: Whether the script is a P2PK output script
Return type: bool

hwilib._script.is_witness(script)¶

Determine whether a script is a segwit output script. If so, also returns the witness version and witness program.

Parameters: script (bytes) – The script
Returns: A tuple of a bool indicating whether the script is a segwit output script, an int representing the witness version, and the bytes of the witness program.
Return type: Tuple[bool, int, bytes]

hwilib._script.is_p2wpkh(script)¶

Determine whether a script is a P2WPKH output script.

Parameters: script (bytes) – The script
Returns: Whether the script is a P2WPKH output script
Return type: bool

hwilib._script.is_p2wsh(script)¶

Determine whether a script is a P2WSH output script.

Parameters: script (bytes) – The script
Returns: Whether the script is a P2WSH output script
Return type: bool

hwilib._script.parse_multisig(script)¶

Determine whether a script is a multisig script. If so, determine the parameters of that multisig.

Parameters: script (bytes) – The script
Returns: None if the script is not multisig. If multisig, returns a tuple of the number of signers required, and a sequence of public key bytes.
Return type: Optional[Tuple[int, Sequence[bytes]]]

Bitcoin Object Python Serializations¶

Modified from the test/test_framework/mininode.py file from the Bitcoin repository

class hwilib._serialize.Readable(*args, **kwargs)¶

Parameters

args (Any) –
kwargs (Any) –

Return type

Any

class hwilib._serialize.Deserializable(*args, **kwargs)¶

Parameters

args (Any) –
kwargs (Any) –

Return type

Any

class hwilib._serialize.Serializable(*args, **kwargs)¶

Parameters

args (Any) –
kwargs (Any) –

Return type

Any

hwilib._serialize.ser_compact_size(size)¶

Serialize an integer using Bitcoin’s compact size unsigned integer serialization.

Parameters: size (int) – The int to serialize
Returns: The int serialized as a compact size unsigned integer
Return type: bytes

hwilib._serialize.deser_compact_size(f)¶

Deserialize a compact size unsigned integer from the beginning of the byte stream.

Parameters: f (hwilib._serialize.Readable) – The byte stream
Returns: The integer that was serialized
Return type: int

hwilib._serialize.deser_string(f)¶

Deserialize a variable length byte string serialized with Bitcoin’s variable length string serialization from a byte stream.

Parameters: f (hwilib._serialize.Readable) – The byte stream
Returns: The byte string that was serialized
Return type: bytes

hwilib._serialize.ser_string(s)¶

Serialize a byte string with Bitcoin’s variable length string serialization.

Parameters: s (bytes) – The byte string to be serialized
Returns: The serialized byte string
Return type: bytes

hwilib._serialize.deser_uint256(f)¶

Deserialize a 256 bit integer serialized with Bitcoin’s 256 bit integer serialization from a byte stream.

Parameters: f (hwilib._serialize.Readable) – The byte stream.
Returns: The integer that was serialized
Return type: int

hwilib._serialize.ser_uint256(u)¶

Serialize a 256 bit integer with Bitcoin’s 256 bit integer serialization.

Parameters: u (int) – The integer to serialize
Returns: The serialized 256 bit integer
Return type: bytes

hwilib._serialize.uint256_from_str(s)¶

Deserialize a 256 bit integer serialized with Bitcoin’s 256 bit integer serialization from a byte string.

Parameters: s (bytes) – The byte string
Returns: The integer that was serialized
Return type: int

hwilib._serialize.deser_vector(f, c)¶

Deserialize a vector of objects with Bitcoin’s object vector serialization from a byte stream.

Parameters

f (hwilib._serialize.Readable) – The byte stream
c (Callable[[], hwilib._serialize.D]) – The class of object to deserialize for each object in the vector

Returns

A list of objects that were serialized

Return type

List[hwilib._serialize.D]

hwilib._serialize.ser_vector(v)¶

Serialize a vector of objects with Bitcoin’s object vector serialzation.

Parameters: v (Sequence[hwilib._serialize.Serializable]) – The list of objects to serialize
Returns: The serialized objects
Return type: bytes

hwilib._serialize.deser_string_vector(f)¶

Deserialize a vector of byte strings from a byte stream.

Parameters: f (hwilib._serialize.Readable) – The byte stream
Returns: The list of byte strings that were serialized
Return type: List[bytes]

hwilib._serialize.ser_string_vector(v)¶

Serialize a list of byte strings as a vector of byte strings.

Parameters: v (List[bytes]) – The list of byte strings to serialize
Returns: The serialized list of byte strings
Return type: bytes

hwilib._serialize.ser_sig_der(r, s)¶

Serialize the r and s values of an ECDSA signature using DER.

Parameters

r (bytes) – The r value bytes
s (bytes) – The s value bytes

Returns

The DER encoded signature

Return type

bytes

hwilib._serialize.ser_sig_compact(r, s, recid)¶

Serialize the r and s values of an ECDSA signature using the compact signature serialization scheme.

Parameters

r (bytes) – The r value bytes
s (bytes) – The s value bytes
recid (bytes) –

Returns

The compact signature

Return type

bytes