From d9e397b599b13d642138480a28c14db7a136bf05 Mon Sep 17 00:00:00 2001
From: Adam Langley <agl@google.com>
Date: Thu, 22 Jan 2015 14:27:53 -0800
Subject: Initial commit of BoringSSL for Android.

---
 src/crypto/cipher/aead.c | 119 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 119 insertions(+)
 create mode 100644 src/crypto/cipher/aead.c

(limited to 'src/crypto/cipher/aead.c')

diff --git a/src/crypto/cipher/aead.c b/src/crypto/cipher/aead.c
new file mode 100644
index 0000000..263e398
--- /dev/null
+++ b/src/crypto/cipher/aead.c
@@ -0,0 +1,119 @@
+/* Copyright (c) 2014, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <openssl/aead.h>
+
+#include <string.h>
+
+#include <openssl/cipher.h>
+#include <openssl/err.h>
+
+#include "internal.h"
+
+
+size_t EVP_AEAD_key_length(const EVP_AEAD *aead) { return aead->key_len; }
+
+size_t EVP_AEAD_nonce_length(const EVP_AEAD *aead) { return aead->nonce_len; }
+
+size_t EVP_AEAD_max_overhead(const EVP_AEAD *aead) { return aead->overhead; }
+
+size_t EVP_AEAD_max_tag_len(const EVP_AEAD *aead) { return aead->max_tag_len; }
+
+int EVP_AEAD_CTX_init(EVP_AEAD_CTX *ctx, const EVP_AEAD *aead,
+                      const uint8_t *key, size_t key_len, size_t tag_len,
+                      ENGINE *impl) {
+  ctx->aead = aead;
+  if (key_len != aead->key_len) {
+    OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_init, CIPHER_R_UNSUPPORTED_KEY_SIZE);
+    return 0;
+  }
+  return aead->init(ctx, key, key_len, tag_len);
+}
+
+void EVP_AEAD_CTX_cleanup(EVP_AEAD_CTX *ctx) {
+  if (ctx->aead == NULL) {
+    return;
+  }
+  ctx->aead->cleanup(ctx);
+  ctx->aead = NULL;
+}
+
+/* check_alias returns 0 if |out| points within the buffer determined by |in|
+ * and |in_len| and 1 otherwise.
+ *
+ * When processing, there's only an issue if |out| points within in[:in_len]
+ * and isn't equal to |in|. If that's the case then writing the output will
+ * stomp input that hasn't been read yet.
+ *
+ * This function checks for that case. */
+static int check_alias(const uint8_t *in, size_t in_len, const uint8_t *out) {
+  if (out <= in) {
+    return 1;
+  } else if (in + in_len <= out) {
+    return 1;
+  }
+  return 0;
+}
+
+int EVP_AEAD_CTX_seal(const EVP_AEAD_CTX *ctx, uint8_t *out, size_t *out_len,
+                      size_t max_out_len, const uint8_t *nonce,
+                      size_t nonce_len, const uint8_t *in, size_t in_len,
+                      const uint8_t *ad, size_t ad_len) {
+  size_t possible_out_len = in_len + ctx->aead->overhead;
+
+  if (possible_out_len < in_len /* overflow */) {
+    OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_seal, CIPHER_R_TOO_LARGE);
+    goto error;
+  }
+
+  if (!check_alias(in, in_len, out)) {
+    OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_seal, CIPHER_R_OUTPUT_ALIASES_INPUT);
+    goto error;
+  }
+
+  if (ctx->aead->seal(ctx, out, out_len, max_out_len, nonce, nonce_len, in,
+                      in_len, ad, ad_len)) {
+    return 1;
+  }
+
+error:
+  /* In the event of an error, clear the output buffer so that a caller
+   * that doesn't check the return value doesn't send raw data. */
+  memset(out, 0, max_out_len);
+  *out_len = 0;
+  return 0;
+}
+
+int EVP_AEAD_CTX_open(const EVP_AEAD_CTX *ctx, uint8_t *out, size_t *out_len,
+                      size_t max_out_len, const uint8_t *nonce,
+                      size_t nonce_len, const uint8_t *in, size_t in_len,
+                      const uint8_t *ad, size_t ad_len) {
+  if (!check_alias(in, in_len, out)) {
+    OPENSSL_PUT_ERROR(CIPHER, EVP_AEAD_CTX_open, CIPHER_R_OUTPUT_ALIASES_INPUT);
+    goto error;
+  }
+
+  if (ctx->aead->open(ctx, out, out_len, max_out_len, nonce, nonce_len, in,
+                      in_len, ad, ad_len)) {
+    return 1;
+  }
+
+error:
+  /* In the event of an error, clear the output buffer so that a caller
+   * that doesn't check the return value doesn't try and process bad
+   * data. */
+  memset(out, 0, max_out_len);
+  *out_len = 0;
+  return 0;
+}
-- 
cgit v1.1