add support for secp256k1

CHANGELOG.rst

@@ -12,6 +12,9 @@ Changelog
   actually dropping support, however we strongly encourage all users to upgrade
   their Python, as Python 2.6 no longer receives support from the Python core
   team.
+* Add support for the
+  :class:`~cryptography.hazmat.primitives.asymmetric.ec.SECP256K1` elliptic
+  curve.
 * Fixed compilation when using an OpenSSL which was compiled with the
   ``no-comp`` (``OPENSSL_NO_COMP``) option.
 * Support :attr:`~cryptography.hazmat.primitives.serialization.Encoding.DER`

docs/hazmat/primitives/asymmetric/ec.rst

@@ -251,6 +251,14 @@ All named curves are providers of :class:`EllipticCurve`.
 
     SECG curve ``secp192r1``. Also called NIST P-192.
 
+
+.. class:: SECP256K1
+
+    .. versionadded:: 0.9
+
+    SECG curve ``secp256k1``.
+
+
 Key Interfaces
 ~~~~~~~~~~~~~~
 

src/cryptography/hazmat/primitives/asymmetric/ec.py

@@ -201,6 +201,12 @@ class SECP256R1(object):
     key_size = 256
 
 
+@utils.register_interface(EllipticCurve)
+class SECP256K1(object):
+    name = "secp256k1"
+    key_size = 256
+
+
 @utils.register_interface(EllipticCurve)
 class SECP224R1(object):
     name = "secp224r1"
@@ -222,6 +228,7 @@ class SECP192R1(object):
     "secp256r1": SECP256R1,
     "secp384r1": SECP384R1,
     "secp521r1": SECP521R1,
+    "secp256k1": SECP256K1,
 
     "sect163k1": SECT163K1,
     "sect233k1": SECT233K1,

tests/hazmat/primitives/test_ec.py

@@ -305,10 +305,17 @@ def test_load_invalid_ec_key_from_numbers(self, backend):
 
     @pytest.mark.parametrize(
         "vector",
-        load_vectors_from_file(
-            os.path.join(
-                "asymmetric", "ECDSA", "FIPS_186-3", "SigGen.txt"),
-            load_fips_ecdsa_signing_vectors
+        itertools.chain(
+            load_vectors_from_file(
+                os.path.join(
+                    "asymmetric", "ECDSA", "FIPS_186-3", "SigGen.txt"),
+                load_fips_ecdsa_signing_vectors
+            ),
+            load_vectors_from_file(
+                os.path.join(
+                    "asymmetric", "ECDSA", "SECP256K1", "SigGen.txt"),
+                load_fips_ecdsa_signing_vectors
+            ),
         )
     )
     def test_signatures(self, backend, vector):