diff --git a/cryptography/bindings/openssl/api.py b/cryptography/bindings/openssl/api.py
index 073cb53..c352d3b 100644
--- a/cryptography/bindings/openssl/api.py
+++ b/cryptography/bindings/openssl/api.py
@@ -72,9 +72,9 @@
         """
         return self.ffi.string(self.lib.OPENSSL_VERSION_TEXT).decode("ascii")
 
-    def supports(self, ciphername):
-        return (self._ffi.NULL !=
-                self._lib.EVP_get_cipherbyname(ciphername.encode("ascii")))
+    def supports_cipher(self, ciphername):
+        return (self.ffi.NULL !=
+                self.lib.EVP_get_cipherbyname(ciphername.encode("ascii")))
 
     def create_block_cipher_context(self, cipher, mode):
         ctx = self.ffi.new("EVP_CIPHER_CTX *")
@@ -85,9 +85,8 @@
         ciphername = "{0}-{1}-{2}".format(
             cipher.name, cipher.key_size, mode.name
         ).lower()
-        evp_cipher = self._lib.EVP_get_cipherbyname(ciphername.encode("ascii"))
-        if evp_cipher == self._ffi.NULL:
-            raise AssertionError("Unsupported cipher: {0}".format(ciphername))
+        evp_cipher = self.lib.EVP_get_cipherbyname(ciphername.encode("ascii"))
+        assert evp_cipher != self.ffi.NULL
         if isinstance(mode, interfaces.ModeWithInitializationVector):
             iv_nonce = mode.initialization_vector
         else:
diff --git a/tests/bindings/test_openssl.py b/tests/bindings/test_openssl.py
index 85ecc49..e5b78d1 100644
--- a/tests/bindings/test_openssl.py
+++ b/tests/bindings/test_openssl.py
@@ -11,8 +11,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import pytest
-
 from cryptography.bindings.openssl.api import api
 
 
@@ -31,18 +29,5 @@
         """
         assert api.openssl_version_text().startswith("OpenSSL")
 
-    def test_supports(self):
-        assert api.supports("not-a-real-cipher") is False
-
-    def test_create_block_cipher_context_with_unsupported_cipher(self):
-        class FakeCipher(object):
-            name = "FakeCipher"
-            key_size = 24
-
-        class FakeMode(object):
-            name = "CCC"
-
-        with pytest.raises(AssertionError):
-            cipher = FakeCipher()
-            mode = FakeMode()
-            api.create_block_cipher_context(cipher, mode)
+    def test_supports_cipher(self):
+        assert api.supports_cipher("not-a-real-cipher") is False
diff --git a/tests/primitives/test_cryptrec.py b/tests/primitives/test_cryptrec.py
index 54ae4d0..fb2bf19 100644
--- a/tests/primitives/test_cryptrec.py
+++ b/tests/primitives/test_cryptrec.py
@@ -23,13 +23,10 @@
 
 import pytest
 
-from cryptography.bindings.openssl.api import api
 from cryptography.primitives.block import BlockCipher, ciphers, modes
 
 from ..utils import load_cryptrec_vectors_from_file
 
-CAMELLIA_ECB_SUPPORTED = api.supports('camellia-128-ecb')
-
 
 def parameterize_encrypt_test(cipher, vector_type, params, fnames):
     return pytest.mark.parametrize(params,
@@ -42,9 +39,7 @@
     )
 
 
-@pytest.mark.skipif("not CAMELLIA_ECB_SUPPORTED")
 class TestCamelliaECB(object):
-
     @parameterize_encrypt_test(
         "Camellia", "NTT",
         ("key", "plaintext", "ciphertext"),
@@ -54,10 +49,13 @@
             "camellia-256-ecb.txt",
         ]
     )
-    def test_NTT(self, key, plaintext, ciphertext):
+    def test_NTT(self, key, plaintext, ciphertext, api):
+        if not api.supports_cipher('camellia-128-ecb'):
+            pytest.skip()
         cipher = BlockCipher(
             ciphers.Camellia(binascii.unhexlify(key)),
             modes.ECB(),
+            api
         )
         actual_ciphertext = cipher.encrypt(binascii.unhexlify(plaintext))
         actual_ciphertext += cipher.finalize()
diff --git a/tests/primitives/test_openssl_vectors.py b/tests/primitives/test_openssl_vectors.py
index 0ecbcd9..ccd0719 100644
--- a/tests/primitives/test_openssl_vectors.py
+++ b/tests/primitives/test_openssl_vectors.py
@@ -28,10 +28,6 @@
 
 from ..utils import load_openssl_vectors_from_file
 
-CAMELLIA_CBC_SUPPORTED = api.supports('camellia-128-cbc')
-CAMELLIA_OFB_SUPPORTED = api.supports('camellia-128-ofb')
-CAMELLIA_CFB_SUPPORTED = api.supports('camellia-128-cfb')
-
 
 def parameterize_encrypt_test(cipher, params, fnames):
     return pytest.mark.parametrize(params,
@@ -42,7 +38,6 @@
     )
 
 
-@pytest.mark.skipif("not CAMELLIA_CBC_SUPPORTED")
 class TestCamelliaCBC(object):
 
     @parameterize_encrypt_test(
@@ -53,6 +48,8 @@
         ]
     )
     def test_OpenSSL(self, key, iv, plaintext, ciphertext):
+        if not api.supports_cipher('camellia-128-cbc'):
+            pytest.skip()
         cipher = BlockCipher(
             ciphers.Camellia(binascii.unhexlify(key)),
             modes.CBC(binascii.unhexlify(iv)),
@@ -62,7 +59,6 @@
         assert binascii.hexlify(actual_ciphertext).upper() == ciphertext
 
 
-@pytest.mark.skipif("not CAMELLIA_OFB_SUPPORTED")
 class TestCamelliaOFB(object):
 
     @parameterize_encrypt_test(
@@ -73,6 +69,8 @@
         ]
     )
     def test_OpenSSL(self, key, iv, plaintext, ciphertext):
+        if not api.supports_cipher('camellia-128-ofb'):
+            pytest.skip()
         cipher = BlockCipher(
             ciphers.Camellia(binascii.unhexlify(key)),
             modes.OFB(binascii.unhexlify(iv)),
@@ -82,7 +80,6 @@
         assert binascii.hexlify(actual_ciphertext).upper() == ciphertext
 
 
-@pytest.mark.skipif("not CAMELLIA_CFB_SUPPORTED")
 class TestCamelliaCFB(object):
 
     @parameterize_encrypt_test(
@@ -93,6 +90,8 @@
         ]
     )
     def test_OpenSSL(self, key, iv, plaintext, ciphertext):
+        if not api.supports_cipher('camellia-128-cfb'):
+            pytest.skip()
         cipher = BlockCipher(
             ciphers.Camellia(binascii.unhexlify(key)),
             modes.CFB(binascii.unhexlify(iv)),