net/quic/crypto/aes_128_gcm_12_decrypter_openssl.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/quic/crypto/aes_128_gcm_12_decrypter.h"
   6
   7 #include <openssl/evp.h>
   8 #include <openssl/tls1.h>
   9
  10 namespace net {
  11
  12 namespace {
  13
  14 const size_t kKeySize = 16;
  15 const size_t kNoncePrefixSize = 4;
  16
  17 }  // namespace
  18
  19 Aes128Gcm12Decrypter::Aes128Gcm12Decrypter()
  20     : AeadBaseDecrypter(EVP_aead_aes_128_gcm(), kKeySize, kAuthTagSize,
  21                         kNoncePrefixSize) {
  22   static_assert(kKeySize <= kMaxKeySize, "key size too big");
  23   static_assert(kNoncePrefixSize <= kMaxNoncePrefixSize,
  24                 "nonce prefix size too big");
  25 }
  26
  27 Aes128Gcm12Decrypter::~Aes128Gcm12Decrypter() {}
  28
  29 const char* Aes128Gcm12Decrypter::cipher_name() const {
  30   return TLS1_TXT_ECDHE_RSA_WITH_AES_128_GCM_SHA256;
  31 }
  32
  33 uint32 Aes128Gcm12Decrypter::cipher_id() const {
  34   // This OpenSSL macro has the value 0x0300C02F. The two most significant bytes
  35   // 0x0300 are OpenSSL specific and are NOT part of the TLS CipherSuite value
  36   // for TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256.
  37   return TLS1_CK_ECDHE_RSA_WITH_AES_128_GCM_SHA256;
  38 }
  39
  40 }  // namespace net