use utils secp256k1 helpers only

Author: Jan Xie

ethereum/specials.py

@@ -1,7 +1,6 @@
 # -*- coding: utf8 -*-
 import bitcoin
 from rlp.utils import ascii_chr
-from secp256k1 import PublicKey, ALL_FLAGS
 
 from ethereum import utils, opcodes
 from ethereum.utils import safe_ord, decode_hex, encode_int32
@@ -29,28 +28,11 @@ def proc_ecrecover(ext, msg):
 
     if r >= bitcoin.N or s >= bitcoin.N or v < 27 or v > 28:
         return 1, msg.gas - opcodes.GECRECOVER, []
-
-    signature_bytes = [0] * 64
-    msg.data.extract_copy(signature_bytes, 0, 64, 32)
-    msg.data.extract_copy(signature_bytes, 32, 96, 32)
-    signature = b''.join(map(ascii_chr, signature_bytes))
-
-    pk = PublicKey(flags=ALL_FLAGS)
     try:
-        pk.public_key = pk.ecdsa_recover(
-            message_hash,
-            pk.ecdsa_recoverable_deserialize(
-                signature,
-                v - 27
-            ),
-            raw=True
-        )
-    except Exception:
-        # Recovery failed
+        pub = utils.ecrecover_to_pub(message_hash, v, r, s)
+    except:
         return 1, msg.gas - gas_cost, []
-
-    pub = pk.serialize(compressed=False)
-    o = [0] * 12 + [safe_ord(x) for x in utils.sha3(pub[1:])[-20:]]
+    o = [0] * 12 + [safe_ord(x) for x in utils.sha3(pub)[-20:]]
     return 1, msg.gas - gas_cost, o
 
 

ethereum/transactions.py

@@ -4,7 +4,6 @@
 from rlp.sedes import big_endian_int, binary
 from rlp.utils import str_to_bytes, ascii_chr
 from ethereum.utils import encode_hex
-from secp256k1 import PublicKey, ALL_FLAGS, PrivateKey
 
 from ethereum.exceptions import InvalidTransaction
 from ethereum import bloom