Remove asn1tools dependency

ethereum · May 31, 2019 · 69edf61 · 69edf61
1 parent b46737e
commit 69edf61
Show file tree

Hide file tree

Showing 2 changed files with 5 additions and 25 deletions.
diff --git a/eth_keys/backends/coincurve.py b/eth_keys/backends/coincurve.py
@@ -19,47 +19,32 @@
 from eth_keys.validation import (
     validate_uncompressed_public_key_bytes,
 )
+from eth_keys.utils import (
+    der,
+)
 
 from .base import BaseECCBackend
 
 
 def is_coincurve_available() -> bool:
     try:
         import coincurve  # noqa: F401
-        import asn1tools  # noqa: F401
     except ImportError:
         return False
     else:
         return True
 
 
-ASN1_ECDSA_SPEC_STRING = """\
-ECDSASpec DEFINITIONS ::= BEGIN
-
-     ECDSASignature ::= SEQUENCE {
-         r   INTEGER,
-         s   INTEGER
-     }
-END
-"""
-
-
 class CoinCurveECCBackend(BaseECCBackend):
     def __init__(self) -> None:
         try:
             import coincurve
         except ImportError:
             raise ImportError("The CoinCurveECCBackend requires the coincurve \
                                library which is not available for import.")
-        try:
-            import asn1tools
-        except ImportError:
-            raise ImportError("The CoinCurveECCBackend requires the asn1tools \
-                               library which is not available for import.")
 
         self.keys = coincurve.keys
         self.ecdsa = coincurve.ecdsa
-        self.asn1_ecdsa_spec = asn1tools.compile_string(ASN1_ECDSA_SPEC_STRING, "der")
 
         super(CoinCurveECCBackend, self).__init__()
 
@@ -83,8 +68,7 @@ def ecdsa_sign_non_recoverable(self,
             msg_hash,
             hasher=None,
         )
-        rs_dict = self.asn1_ecdsa_spec.decode("ECDSASignature", der_encoded_signature)
-        rs = (rs_dict["r"], rs_dict["s"])
+        rs = der.two_int_sequence_decoder(der_encoded_signature)
 
         signature = NonRecoverableSignature(rs=rs, backend=self)
         return signature
@@ -93,10 +77,7 @@ def ecdsa_verify(self,
                      msg_hash: bytes,
                      signature: BaseSignature,
                      public_key: PublicKey) -> bool:
-        der_encoded_signature = bytes(self.asn1_ecdsa_spec.encode("ECDSASignature", {
-            "r": signature.r,
-            "s": signature.s,
-        }))
+        der_encoded_signature = der.two_int_sequence_encoder((signature.r, signature.s))
         coincurve_public_key = self.keys.PublicKey(b"\x04" + public_key.to_bytes())
         return coincurve_public_key.verify(
             der_encoded_signature,

diff --git a/tox.ini b/tox.ini
@@ -15,7 +15,6 @@ commands=
     backends: py.test {posargs:tests/backends}
 deps = .[test]
     backends: coincurve>=7.0.0,<8.0.0
-              asn1tools>=0.146.1,<1.0.0
 setenv =
     backends: REQUIRE_COINCURVE=True
 basepython =