1 files changed, 124 insertions, 0 deletions
diff --git a/lib/crypto/c_src/chacha20.c b/lib/crypto/c_src/chacha20.c
new file mode 100644
index 0000000000..cfcc395dca
--- /dev/null
+++ b/lib/crypto/c_src/chacha20.c
@@ -0,0 +1,124 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2010-2018. 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 "chacha20.h"
+#include "cipher.h"
+
+ERL_NIF_TERM chacha20_stream_init(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{/* (Key, IV) */
+#if defined(HAVE_CHACHA20)
+    ErlNifBinary     key_bin, ivec_bin;
+    struct evp_cipher_ctx *ctx = NULL;
+    const EVP_CIPHER *cipher;
+    ERL_NIF_TERM     ret;
+
+    ASSERT(argc == 2);
+
+    if (!enif_inspect_iolist_as_binary(env, argv[0], &key_bin))
+        goto bad_arg;
+    if (key_bin.size != 32)
+        goto bad_arg;
+    if (!enif_inspect_binary(env, argv[1], &ivec_bin))
+        goto bad_arg;
+    if (ivec_bin.size != 16)
+        goto bad_arg;
+
+    cipher = EVP_chacha20();
+
+    if ((ctx = enif_alloc_resource(evp_cipher_ctx_rtype, sizeof(struct evp_cipher_ctx))) == NULL)
+        goto err;
+    if ((ctx->ctx = EVP_CIPHER_CTX_new()) == NULL)
+        goto err;
+
+    if (EVP_CipherInit_ex(ctx->ctx, cipher, NULL,
+                          key_bin.data, ivec_bin.data, 1) != 1)
+        goto err;
+    if (EVP_CIPHER_CTX_set_padding(ctx->ctx, 0) != 1)
+        goto err;
+
+    ret = enif_make_resource(env, ctx);
+    goto done;
+
+ bad_arg:
+    return enif_make_badarg(env);
+
+ err:
+    ret = enif_make_badarg(env);
+
+ done:
+    if (ctx)
+        enif_release_resource(ctx);
+    return ret;
+
+#else
+    return enif_raise_exception(env, atom_notsup);
+#endif
+}
+
+ERL_NIF_TERM chacha20_stream_crypt(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{/* (State, Data) */
+#if defined(HAVE_CHACHA20)
+    struct evp_cipher_ctx *ctx = NULL, *new_ctx = NULL;
+    ErlNifBinary   data_bin;
+    ERL_NIF_TERM   ret, cipher_term;
+    unsigned char  *out;
+    int            outl = 0;
+
+    ASSERT(argc == 2);
+
+    if (!enif_get_resource(env, argv[0], evp_cipher_ctx_rtype, (void**)&ctx))
+        goto bad_arg;
+    if (!enif_inspect_iolist_as_binary(env, argv[1], &data_bin))
+        goto bad_arg;
+    if (data_bin.size > INT_MAX)
+        goto bad_arg;
+
+    if ((new_ctx = enif_alloc_resource(evp_cipher_ctx_rtype, sizeof(struct evp_cipher_ctx))) == NULL)
+        goto err;
+    if ((new_ctx->ctx = EVP_CIPHER_CTX_new()) == NULL)
+        goto err;
+
+    if (EVP_CIPHER_CTX_copy(new_ctx->ctx, ctx->ctx) != 1)
+        goto err;
+    if ((out = enif_make_new_binary(env, data_bin.size, &cipher_term)) == NULL)
+        goto err;
+    if (EVP_CipherUpdate(new_ctx->ctx, out, &outl, data_bin.data, (int)data_bin.size) != 1)
+        goto err;
+    ASSERT(outl >= 0 && (size_t)outl == data_bin.size);
+
+    ret = enif_make_tuple2(env, enif_make_resource(env, new_ctx), cipher_term);
+    CONSUME_REDS(env, data_bin);
+    goto done;
+
+ bad_arg:
+    return enif_make_badarg(env);
+
+ err:
+    ret = enif_make_badarg(env);
+
+ done:
+    if (new_ctx)
+        enif_release_resource(new_ctx);
+    return ret;
+
+#else
+    return enif_raise_exception(env, atom_notsup);
+#endif
+}