tfix #4717 - electrum - Electrum Bitcoin wallet
HTML git clone https://git.parazyd.org/electrum
DIR Log
DIR Files
DIR Refs
DIR Submodules
---
DIR commit d1f11f5fe94264f85a6c03afd2c43edb6134aeab
DIR parent f05f3b430aa0d9060ed51f720607a0b012f3ce99
HTML Author: SomberNight <somber.night@protonmail.com>
Date: Fri, 14 Sep 2018 16:12:47 +0200
fix #4717
Diffstat:
M electrum/ecc.py | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
---
DIR diff --git a/electrum/ecc.py b/electrum/ecc.py
t@@ -38,6 +38,7 @@ from ecdsa.util import string_to_number, number_to_string
from .util import bfh, bh2u, assert_bytes, print_error, to_bytes, InvalidPassword, profiler
from .crypto import (Hash, aes_encrypt_with_iv, aes_decrypt_with_iv, hmac_oneshot)
from .ecc_fast import do_monkey_patching_of_python_ecdsa_internals_with_libsecp256k1
+from . import msqr
do_monkey_patching_of_python_ecdsa_internals_with_libsecp256k1()
t@@ -94,20 +95,19 @@ def point_to_ser(P, compressed=True) -> bytes:
return bfh('04'+('%064x' % x)+('%064x' % y))
-def get_y_coord_from_x(x, odd=True):
+def get_y_coord_from_x(x: int, odd: bool=True) -> int:
curve = curve_secp256k1
_p = curve.p()
_a = curve.a()
_b = curve.b()
- for offset in range(128):
- Mx = x + offset
- My2 = pow(Mx, 3, _p) + _a * pow(Mx, 2, _p) + _b % _p
- My = pow(My2, (_p + 1) // 4, _p)
- if curve.contains_point(Mx, My):
- if odd == bool(My & 1):
- return My
- return _p - My
- raise Exception('ECC_YfromX: No Y found')
+ x = x % _p
+ y2 = (pow(x, 3, _p) + _a * x + _b) % _p
+ y = msqr.modular_sqrt(y2, _p)
+ if curve.contains_point(x, y):
+ if odd == bool(y & 1):
+ return y
+ return _p - y
+ raise InvalidECPointException()
def ser_to_point(ser: bytes) -> (int, int):