net/quic/crypto/aes_128_gcm_12_encrypter_nss.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_encrypter.h"
   6
   7 #include <pk11pub.h>
   8 #include <secerr.h>
   9
  10 #include "crypto/aes_128_gcm_helpers_nss.h"
  11
  12 using base::StringPiece;
  13
  14 namespace net {
  15
  16 namespace {
  17
  18 const size_t kKeySize = 16;
  19 const size_t kNoncePrefixSize = 4;
  20
  21 SECStatus My_Encrypt(PK11SymKey* key,
  22                      CK_MECHANISM_TYPE mechanism,
  23                      SECItem* param,
  24                      unsigned char* out,
  25                      unsigned int* out_len,
  26                      unsigned int max_len,
  27                      const unsigned char* data,
  28                      unsigned int data_len) {
  29   return crypto::PK11EncryptHelper(key, mechanism, param, out, out_len, max_len,
  30                                    data, data_len);
  31 }
  32
  33 }  // namespace
  34
  35 Aes128Gcm12Encrypter::Aes128Gcm12Encrypter()
  36     : AeadBaseEncrypter(CKM_AES_GCM, My_Encrypt, kKeySize, kAuthTagSize,
  37                         kNoncePrefixSize) {
  38   static_assert(kKeySize <= kMaxKeySize, "key size too big");
  39   static_assert(kNoncePrefixSize <= kMaxNoncePrefixSize,
  40                 "nonce prefix size too big");
  41 }
  42
  43 Aes128Gcm12Encrypter::~Aes128Gcm12Encrypter() {}
  44
  45 void Aes128Gcm12Encrypter::FillAeadParams(StringPiece nonce,
  46                                           StringPiece associated_data,
  47                                           size_t auth_tag_size,
  48                                           AeadParams* aead_params) const {
  49   aead_params->len = sizeof(aead_params->data.gcm_params);
  50   CK_GCM_PARAMS* gcm_params = &aead_params->data.gcm_params;
  51   gcm_params->pIv =
  52       reinterpret_cast<CK_BYTE*>(const_cast<char*>(nonce.data()));
  53   gcm_params->ulIvLen = nonce.size();
  54   gcm_params->pAAD =
  55       reinterpret_cast<CK_BYTE*>(const_cast<char*>(associated_data.data()));
  56   gcm_params->ulAADLen = associated_data.size();
  57   gcm_params->ulTagBits = auth_tag_size * 8;
  58 }
  59
  60 }  // namespace net