time taken to add points changes to around 35% of what it was with python-ecdsa
-----
# benchmark runs before:
> python3.7-64 ..\wspace\201909_libsecp256k1_point_addition\bench.py
time taken: 3.7693 seconds
> python3.7-64 ..\wspace\201909_libsecp256k1_point_addition\bench.py
time taken: 3.8123 seconds
> python3.7-64 ..\wspace\201909_libsecp256k1_point_addition\bench.py
time taken: 3.7937 seconds
# benchmark runs after:
> python3.7-64 ..\wspace\201909_libsecp256k1_point_addition\bench.py
time taken: 1.3127 seconds
> python3.7-64 ..\wspace\201909_libsecp256k1_point_addition\bench.py
time taken: 1.3000 seconds
> python3.7-64 ..\wspace\201909_libsecp256k1_point_addition\bench.py
time taken: 1.3128 seconds
-----
# benchmark script:
import os
import time
from electrum.ecc import generator
from electrum.crypto import sha256
rand_bytes = os.urandom(32)
#rand_bytes = bytes.fromhex('d3d88983b91ee6dfd546ccf89b9a1ffb23b01bf2eef322c2808cb3d951a3c116')
point_pairs = []
for i in range(30000):
rand_bytes = sha256(rand_bytes)
rand_int = int.from_bytes(rand_bytes, "big")
a = generator() * rand_int
rand_bytes = sha256(rand_bytes)
rand_int = int.from_bytes(rand_bytes, "big")
b = generator() * rand_int
point_pairs.append((a,b))
t0 = time.time()
for a, b in point_pairs:
c = a + b
t = time.time() - t0
print(f"time taken: {t:.4f} seconds")
This bug is triggered if ecc_fast._libsecp256k1 and/or
crypto.AES are not present.
Before, if the first test would have raised an exception
it would have been implicitly caught by returning from
the finally block and hence this effectively masks the
test's outcome. Now, the exception is properly propagated
causing the test to fail if an exception is raised.
