# Copyright (c) 2026 Emanuele Bellocchia
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
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# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
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#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# THE SOFTWARE.
"""Module for ed25519 keys."""
# Imports
from typing import Any
from nacl import exceptions, signing
from typing_extensions import override
from bip_utils.ecc.common.ikeys import IPrivateKey, IPublicKey
from bip_utils.ecc.common.ipoint import IPoint
from bip_utils.ecc.curve.elliptic_curve_types import EllipticCurveTypes
from bip_utils.ecc.ed25519.ed25519_point import Ed25519Point
from bip_utils.ecc.ed25519.lib import ed25519_lib
from bip_utils.utils.misc import BytesUtils, DataBytes
class Ed25519KeysConst:
"""Class container for ed25519 keys constants."""
# Public key prefix
PUB_KEY_PREFIX: bytes = b"\x00"
# Public key length in bytes
PUB_KEY_BYTE_LEN: int = 32
# Private key length in bytes
PRIV_KEY_BYTE_LEN: int = 32
class Ed25519PublicKey(IPublicKey):
"""Ed25519 public key class."""
m_ver_key: signing.VerifyKey
@override
@classmethod
def FromBytes(cls,
key_bytes: bytes) -> IPublicKey:
"""
Construct class from key bytes.
Args:
key_bytes (bytes): Key bytes
Returns:
IPublicKey: IPublicKey object
Raises:
ValueError: If key bytes are not valid
"""
# Remove the 0x00 prefix if present because nacl requires 32-byte length
if (len(key_bytes) == Ed25519KeysConst.PUB_KEY_BYTE_LEN + len(Ed25519KeysConst.PUB_KEY_PREFIX)
and key_bytes[0] == BytesUtils.ToInteger(Ed25519KeysConst.PUB_KEY_PREFIX)):
key_bytes = key_bytes[1:]
# nacl doesn't check if the point lies on curve
if not ed25519_lib.point_is_on_curve(key_bytes):
raise ValueError("Invalid public key bytes")
try:
return cls(signing.VerifyKey(key_bytes))
except (exceptions.RuntimeError, exceptions.ValueError) as ex:
raise ValueError("Invalid public key bytes") from ex
@override
@classmethod
def FromPoint(cls,
key_point: IPoint) -> IPublicKey:
"""
Construct class from key point.
Args:
key_point (IPoint object): Key point
Returns:
IPublicKey: IPublicKey object
Raises:
ValueError: If key point is not valid
"""
return cls.FromBytes(key_point.RawEncoded().ToBytes())
def __init__(self,
key_obj: signing.VerifyKey) -> None:
"""
Construct class.
Args:
key_obj (signing.VerifyKey): Key object
"""
self.m_ver_key = key_obj
@override
@staticmethod
def CurveType() -> EllipticCurveTypes:
"""
Get the elliptic curve type.
Returns:
EllipticCurveTypes: Elliptic curve type
"""
return EllipticCurveTypes.ED25519
@override
@staticmethod
def CompressedLength() -> int:
"""
Get the compressed key length.
Returns:
int: Compressed key length
"""
return Ed25519KeysConst.PUB_KEY_BYTE_LEN + len(Ed25519KeysConst.PUB_KEY_PREFIX)
@override
@staticmethod
def UncompressedLength() -> int:
"""
Get the uncompressed key length.
Returns:
int: Uncompressed key length
"""
return Ed25519PublicKey.CompressedLength()
@override
def UnderlyingObject(self) -> Any:
"""
Get the underlying object.
Returns:
Any: Underlying object
"""
return self.m_ver_key
@override
def RawCompressed(self) -> DataBytes:
"""
Return raw compressed public key.
Returns:
DataBytes object: DataBytes object
"""
return DataBytes(Ed25519KeysConst.PUB_KEY_PREFIX + bytes(self.m_ver_key))
@override
def RawUncompressed(self) -> DataBytes:
"""
Return raw uncompressed public key.
Returns:
DataBytes object: DataBytes object
"""
# Same as compressed
return self.RawCompressed()
@override
def Point(self) -> IPoint:
"""
Get public key point.
Returns:
IPoint object: IPoint object
"""
return Ed25519Point(bytes(self.m_ver_key))
class Ed25519PrivateKey(IPrivateKey):
"""Ed25519 private key class."""
m_sign_key: signing.SigningKey
@override
@classmethod
def FromBytes(cls,
key_bytes: bytes) -> IPrivateKey:
"""
Construct class from key bytes.
Args:
key_bytes (bytes): Key bytes
Returns:
IPrivateKey: IPrivateKey object
Raises:
ValueError: If key bytes are not valid
"""
try:
return cls(signing.SigningKey(key_bytes))
except (exceptions.RuntimeError, exceptions.ValueError) as ex:
raise ValueError("Invalid private key bytes") from ex
def __init__(self,
key_obj: signing.SigningKey) -> None:
"""
Construct class.
Args:
key_obj (signing.SigningKey): Key object
"""
self.m_sign_key = key_obj
@override
@staticmethod
def CurveType() -> EllipticCurveTypes:
"""
Get the elliptic curve type.
Returns:
EllipticCurveTypes: Elliptic curve type
"""
return EllipticCurveTypes.ED25519
@override
@staticmethod
def Length() -> int:
"""
Get the key length.
Returns:
int: Key length
"""
return Ed25519KeysConst.PRIV_KEY_BYTE_LEN
@override
def UnderlyingObject(self) -> Any:
"""
Get the underlying object.
Returns:
Any: Underlying object
"""
return self.m_sign_key
@override
def Raw(self) -> DataBytes:
"""
Return raw private key.
Returns:
DataBytes object: DataBytes object
"""
return DataBytes(bytes(self.m_sign_key))
@override
def PublicKey(self) -> IPublicKey:
"""
Get the public key correspondent to the private one.
Returns:
IPublicKey object: IPublicKey object
"""
return Ed25519PublicKey(self.m_sign_key.verify_key)