modtest ecc: use ecdsa package for reference sig check

nix/user-packages.nix

@@ -40,7 +40,6 @@ rec {
 
     python-packages = with python.pkgs; {
         # pycryptodome     = pycryptodome;    # altcoins
-        # py-ecc           = py-ecc;          # test suite
         # pysocks          = pysocks;         # XMR
         # monero           = monero;          # XMR (test suite)
         # eth-keys         = eth-keys;        # ETH, ETC (test suite)

test-requirements.txt

@@ -1,4 +1,3 @@
 pycoin
 monero
 eth_keys
-py_ecc

test/include/ecc.py

@@ -12,7 +12,7 @@
 test.include.ecc: elliptic curve utilities for the MMGen test suite
 """
 
-import ecdsa
+import ecdsa, hashlib
 from mmgen.proto.secp256k1.keygen import pubkey_format
 
 def _pubkey_to_pub_point(vk_bytes):
@@ -41,3 +41,14 @@ def pubkey_tweak_add_pyecdsa(vk_bytes, pk_addend_bytes):
 	return pubkey_format(
 		ecdsa.VerifyingKey.from_public_point(point_sum, curve=ecdsa.curves.SECP256k1).to_string(),
 		compressed = len(vk_bytes) == 33)
+
+def sign_msghash_pyecdsa(msghash, privkey):
+	ec_privkey = ecdsa.SigningKey.from_string(privkey, curve=ecdsa.curves.SECP256k1)
+	return ec_privkey.sign_digest_deterministic(
+		msghash,
+		hashfunc = hashlib.sha256,
+		sigencode = ecdsa.util.sigencode_string_canonize)
+
+def verify_sig_pyecdsa(sig, msghash, pubkey):
+	ec_pubkey = ecdsa.VerifyingKey.from_string(pubkey, curve=ecdsa.curves.SECP256k1)
+	return ec_pubkey.verify_digest(sig, msghash)

test/modtest_d/ecc.py

@@ -4,9 +4,6 @@
 test.modtest_d.ecc: elliptic curve unit test for the MMGen suite
 """
 
-import ecdsa
-from py_ecc.secp256k1.secp256k1 import ecdsa_raw_sign
-
 from mmgen.proto.secp256k1.secp256k1 import (
 	pubkey_gen,
 	pubkey_tweak_add,
@@ -16,17 +13,11 @@ from mmgen.proto.secp256k1.secp256k1 import (
 	verify_sig)
 
 from ..include.common import vmsg
-from ..include.ecc import pubkey_tweak_add_pyecdsa
+from ..include.ecc import pubkey_tweak_add_pyecdsa, sign_msghash_pyecdsa, verify_sig_pyecdsa
 from mmgen.protocol import CoinProtocol
 
 secp256k1_group_order = CoinProtocol.Secp256k1.secp256k1_group_order
 
-def sign_msghash_pyecc(msghash, privkey):
-	v, r, s = ecdsa_raw_sign(msghash, privkey)
-	return (
-		r.to_bytes(length=32) + s.to_bytes(length=32),
-		v - 27)
-
 class unit_tests:
 
 	def sig_ops(self, name, ut):
@@ -44,17 +35,16 @@ class unit_tests:
 			vmsg(f'   privkey: {privkey.hex()}')
 			pubkey = pubkey_gen(privkey, 1)
 			sig, recid = sign_msghash(msghash, privkey)
-			sig_chk, _ = sign_msghash_pyecc(msghash, privkey)
+			sig_chk = sign_msghash_pyecdsa(msghash, privkey)
 			if sig != sig_chk:
 				import time
 				from mmgen.util import ymsg
-				ymsg('Warning: signature (libsecp256k1) does not match reference value (py_ecc)!')
+				ymsg(f'Warning: signature ({sig.hex()}) doesn’t match reference value ({sig_chk.hex()})!')
 				time.sleep(1)
 			vmsg(f'   recid:   {recid}')
 			assert recid in (0, 1)
-			ec_pubkey = ecdsa.VerifyingKey.from_string(pubkey, curve=ecdsa.curves.SECP256k1)
-			assert ec_pubkey.verify_digest(sig, msghash), 'signature verification failed (py-ecdsa)'
 			assert verify_sig(sig, msghash, pubkey) == 1, 'signature verification failed (secp256k1)'
+			assert verify_sig_pyecdsa(sig, msghash, pubkey) == 1, 'signature verification failed (ecdsa)'
 			pubkey_rec = pubkey_recover(msghash, sig, recid, True)
 			assert pubkey == pubkey_rec, f'{pubkey.hex()} != {pubkey_rec.hex()}'
 		return True

test/modtest_d/testdep.py

@@ -67,8 +67,3 @@ class unit_tests:
 	def ssh_socks_proxy(self, name, ut):
 		from test.cmdtest_d.include.proxy import TestProxy
 		return TestProxy(None, cfg)
-
-	def py_ecc(self, name, ut):
-		from py_ecc.secp256k1 import privtopub
-		privtopub(b'f' * 32)
-		return True