1 files changed, 51 insertions, 0 deletions
diff --git a/lib/crypto/c_src/hash_equals.c b/lib/crypto/c_src/hash_equals.c
new file mode 100644
index 0000000000..85f54b14eb
--- /dev/null
+++ b/lib/crypto/c_src/hash_equals.c
@@ -0,0 +1,51 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2010-2021. All Rights Reserved.
+ *
+ * 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.
+ *
+ * %CopyrightEnd%
+
+ */
+
+#include "common.h"
+#include "hash_equals.h"
+
+ERL_NIF_TERM hash_equals_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+#ifdef HAVE_OPENSSL_CRYPTO_MEMCMP
+    ErlNifBinary s1, s2;
+
+    ASSERT(argc == 2);
+
+    if (!enif_inspect_binary(env, argv[0], &s1))
+        goto bad_arg;
+    if (!enif_inspect_binary(env, argv[1], &s2))
+        goto bad_arg;
+
+    if (s1.size != s2.size)
+        goto err;
+
+    if (CRYPTO_memcmp(s1.data, s2.data, s1.size) == 0)
+        return enif_make_atom(env, "true");
+
+    return enif_make_atom(env, "false");
+
+ bad_arg:
+ err:
+    return enif_make_badarg(env);
+#else
+    return EXCP_NOTSUP(env, "Unsupported CRYPTO_memcmp");
+#endif
+}