starred/FindMy.py
1
0
Fork 0
mirror of https://github.com/malmeloo/FindMy.py.git synced 2026-04-18 17:54:08 +02:00
Code Issues Packages Projects Releases Wiki Activity

Cleanup leftover code

Browse Source
This commit is contained in:
Mike A
2024-02-10 20:12:31 +01:00
parent f1592e13fa
commit 55d6c9f8ff
1 changed files with 0 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files

66
findmy/util/crypto.py
View File

@@ -1,71 +1,11 @@
"""Pure-python NIST P-224 Elliptic Curve cryptography. Used for some Apple algorithms."""
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import ec
from cryptography.hazmat.primitives.kdf.x963kdf import X963KDF
ECPoint = tuple[float, float]
P224_A = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFE
P224_N = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFF16A2E0B8F03E13DD29455C5C2A3D
P224_G = (
0xB70E0CBD6BB4BF7F321390B94A03C1D356C21122343280D6115C1D21,
0xBD376388B5F723FB4C22DFE6CD4375A05A07476444D5819985007E34,
)
P224_P = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF000000000000000000000001
# Old code. Remove if replacement is confirmed to be working.
# ruff: noqa: ERA001
#
# def _ec_add_points(p1: ECPoint, p2: ECPoint) -> ECPoint:
# """
# Add two points on a P-224 elliptic curve. (0, 0) is identity.
#
# https://en.wikipedia.org/wiki/Elliptic_curve_point_multiplication#Point_addition
# """
# (x1, y1), (x2, y2) = p1, p2
#
# if p1 == (0, 0): # identity case 1
# return p2
# if p2 == (0, 0): # identity case 2
# return p1
# if x1 == x2 and y1 == -1 * y2: # additive inverse
# return 0, 0
#
# if p1 == p2: # point doubling using limit
# slope = (3 * x1 ** 2 + P224_A) / (2 * y1)
# else:
# slope = (y2 - y1) / (x2 - x1)
#
# x = slope ** 2 - x1 - x2
# y = slope * (x1 - x) - y1
#
# return x, y
#
#
# def _ec_scalar_mul(scalar: int, p: ECPoint) -> ECPoint:
# """
# Scalar multiplication on a point on a P-224 elliptic curve.
#
# https://en.wikipedia.org/wiki/Elliptic_curve_point_multiplication#Double-and-add
# """
# res = (0, 0)
# cur = p
# while scalar > 0:
# if scalar & 1:
# res = _ec_add_points(res, cur)
# cur = _ec_add_points(cur, cur)
# scalar >>= 1
# return res
#
#
# def derive_ps_key(pubkey: ECPoint, sk: bytes) -> ECPoint:
# at = _x963_kdf(sk, b"diversify", 72)
# u = int.from_bytes(at[:36], "big") % (P224_N - 1) + 1
# v = int.from_bytes(at[36:], "big") % (P224_N - 1) + 1
#
# return _ec_add_points(_ec_scalar_mul(u, pubkey), _ec_scalar_mul(v, P224_G))
def x963_kdf(value: bytes, si: bytes, length: int) -> bytes:
@@ -98,9 +38,3 @@ def derive_ps_key(privkey: bytes, sk: bytes) -> bytes:
key = (u * priv_int + v) % P224_N
return key.to_bytes(28, "big")
def _get_pubkey(privkey: int) -> ECPoint:
key = ec.derive_private_key(privkey, ec.SECP224R1())
pubkey = key.public_key().public_numbers()
return pubkey.x, pubkey.y