Merge pull request #918 from Ayrx/cmac-bindings

CMAC OpenSSL bindings
diff --git a/cryptography/hazmat/bindings/openssl/binding.py b/cryptography/hazmat/bindings/openssl/binding.py
index 927406c..acf9d42 100644
--- a/cryptography/hazmat/bindings/openssl/binding.py
+++ b/cryptography/hazmat/bindings/openssl/binding.py
@@ -48,6 +48,7 @@
         "asn1",
         "bignum",
         "bio",
+        "cmac",
         "conf",
         "crypto",
         "dh",
diff --git a/cryptography/hazmat/bindings/openssl/cmac.py b/cryptography/hazmat/bindings/openssl/cmac.py
new file mode 100644
index 0000000..c8bcc82
--- /dev/null
+++ b/cryptography/hazmat/bindings/openssl/cmac.py
@@ -0,0 +1,65 @@
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import absolute_import, division, print_function
+
+INCLUDES = """
+#if OPENSSL_VERSION_NUMBER >= 0x10001000L
+#include <openssl/cmac.h>
+#endif
+"""
+
+TYPES = """
+static const int Cryptography_HAS_CMAC;
+typedef ... CMAC_CTX;
+"""
+
+FUNCTIONS = """
+"""
+
+MACROS = """
+CMAC_CTX *CMAC_CTX_new(void);
+int CMAC_Init(CMAC_CTX *, const void *, size_t, const EVP_CIPHER *, ENGINE *);
+int CMAC_Update(CMAC_CTX *, const void *, size_t);
+int CMAC_Final(CMAC_CTX *, unsigned char *, size_t *);
+int CMAC_CTX_copy(CMAC_CTX *, const CMAC_CTX *);
+void CMAC_CTX_free(CMAC_CTX *);
+"""
+
+CUSTOMIZATIONS = """
+#if OPENSSL_VERSION_NUMBER < 0x10001000L
+
+static const long Cryptography_HAS_CMAC = 0;
+typedef void CMAC_CTX;
+CMAC_CTX *(*CMAC_CTX_new)(void) = NULL;
+int (*CMAC_Init)(CMAC_CTX *, const void *, size_t, const EVP_CIPHER *,
+    ENGINE *) = NULL;
+int (*CMAC_Update)(CMAC_CTX *, const void *, size_t) = NULL;
+int (*CMAC_Final)(CMAC_CTX *, unsigned char *, size_t *) = NULL;
+int (*CMAC_CTX_copy)(CMAC_CTX *, const CMAC_CTX *) = NULL;
+void (*CMAC_CTX_free)(CMAC_CTX *) = NULL;
+#else
+static const long Cryptography_HAS_CMAC = 1;
+#endif
+"""
+
+CONDITIONAL_NAMES = {
+    "Cryptography_HAS_CMAC": [
+        "CMAC_CTX_new",
+        "CMAC_Init",
+        "CMAC_Update",
+        "CMAC_Final",
+        "CMAC_CTX_copy",
+        "CMAC_CTX_free",
+    ],
+}