tminor clean-up of prev. util.xor_bytes - electrum - Electrum Bitcoin wallet
HTML git clone https://git.parazyd.org/electrum
DIR Log
DIR Files
DIR Refs
DIR Submodules
---
DIR commit 053c571d7479370b8dce912918451823cad00abf
DIR parent 47b1bed53933dd1f24f8e68ff97ae8ab778ea9cc
HTML Author: SomberNight <somber.night@protonmail.com>
Date: Fri, 4 May 2018 13:01:46 +0200
minor clean-up of prev. util.xor_bytes
Diffstat:
M electrum/util.py | 6 ++++++
M lib/lnbase.py | 15 ++++++---------
2 files changed, 12 insertions(+), 9 deletions(-)
---
DIR diff --git a/electrum/util.py b/electrum/util.py
t@@ -468,6 +468,12 @@ def bh2u(x: bytes) -> str:
return x.hex()
+def xor_bytes(a: bytes, b: bytes) -> bytes:
+ size = min(len(a), len(b))
+ return ((int.from_bytes(a[:size], "big") ^ int.from_bytes(b[:size], "big"))
+ .to_bytes(size, "big"))
+
+
def user_dir():
if 'ANDROID_DATA' in os.environ:
return android_data_dir()
DIR diff --git a/lib/lnbase.py b/lib/lnbase.py
t@@ -31,7 +31,7 @@ from .bitcoin import (public_key_from_private_key, ser_to_point, point_to_ser,
from . import bitcoin
from . import constants
from . import transaction
-from .util import PrintError, bh2u, print_error, bfh, profiler
+from .util import PrintError, bh2u, print_error, bfh, profiler, xor_bytes
from .transaction import opcodes, Transaction
from collections import namedtuple, defaultdict
t@@ -1306,7 +1306,6 @@ NUM_MAX_HOPS_IN_PATH = 20
HOPS_DATA_SIZE = 1300 # also sometimes called routingInfoSize in bolt-04
PER_HOP_FULL_SIZE = 65 # HOPS_DATA_SIZE / 20
NUM_STREAM_BYTES = HOPS_DATA_SIZE + PER_HOP_FULL_SIZE
-PER_HOP_PAYLOAD_SIZE = 32 # PER_HOP_FULL_SIZE - len(realm) - len(HMAC)
PER_HOP_HMAC_SIZE = 32
t@@ -1379,8 +1378,8 @@ def new_onion_packet(payment_path_pubkeys: Sequence[bytes], session_key: bytes,
ephemeral_key = ephemeral_key_int.to_bytes(32, byteorder="big")
filler = generate_filler(b'rho', num_hops, PER_HOP_FULL_SIZE, hop_shared_secrets)
- mix_header = bytearray(HOPS_DATA_SIZE)
- next_hmac = bytearray(PER_HOP_HMAC_SIZE)
+ mix_header = bytes(HOPS_DATA_SIZE)
+ next_hmac = bytes(PER_HOP_HMAC_SIZE)
# compute routing info and MAC for each hop
for i in range(num_hops-1, -1, -1):
t@@ -1390,8 +1389,7 @@ def new_onion_packet(payment_path_pubkeys: Sequence[bytes], session_key: bytes,
stream_bytes = generate_cipher_stream(rho_key, NUM_STREAM_BYTES)
mix_header = mix_header[:-PER_HOP_FULL_SIZE]
mix_header = hops_data[i].to_bytes() + mix_header
- mix_header = ((int.from_bytes(mix_header, "big") ^ int.from_bytes(stream_bytes[:HOPS_DATA_SIZE], "big"))
- .to_bytes(HOPS_DATA_SIZE, "big"))
+ mix_header = xor_bytes(mix_header, stream_bytes)
if i == num_hops - 1:
mix_header = mix_header[:-len(filler)] + filler
packet = mix_header + associated_data
t@@ -1399,7 +1397,7 @@ def new_onion_packet(payment_path_pubkeys: Sequence[bytes], session_key: bytes,
return OnionPacket(
public_key=bfh(EC_KEY(session_key).get_public_key()),
- hops_data=bytes(mix_header),
+ hops_data=mix_header,
hmac=next_hmac)
t@@ -1413,8 +1411,7 @@ def generate_filler(key_type: bytes, num_hops: int, hop_size: int,
filler += bytearray(hop_size)
stream_key = get_bolt04_onion_key(key_type, shared_secrets[i])
stream_bytes = generate_cipher_stream(stream_key, filler_size)
- filler = ((int.from_bytes(filler, "big") ^ int.from_bytes(stream_bytes, "big"))
- .to_bytes(filler_size, "big"))
+ filler = xor_bytes(filler, stream_bytes)
return filler[(NUM_MAX_HOPS_IN_PATH-num_hops+2)*hop_size:]