crypto/secure_hash_openssl.cc

   1 // Copyright (c) 2012 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 "crypto/secure_hash.h"
   6
   7 #include <openssl/crypto.h>
   8 #include <openssl/sha.h>
   9
  10 #include "base/basictypes.h"
  11 #include "base/logging.h"
  12 #include "base/pickle.h"
  13 #include "crypto/openssl_util.h"
  14
  15 namespace crypto {
  16
  17 namespace {
  18
  19 const char kSHA256Descriptor[] = "OpenSSL";
  20
  21 class SecureHashSHA256OpenSSL : public SecureHash {
  22  public:
  23   static const int kSecureHashVersion = 1;
  24
  25   SecureHashSHA256OpenSSL() {
  26     SHA256_Init(&ctx_);
  27   }
  28
  29   virtual ~SecureHashSHA256OpenSSL() {
  30     OPENSSL_cleanse(&ctx_, sizeof(ctx_));
  31   }
  32
  33   virtual void Update(const void* input, size_t len) OVERRIDE {
  34     SHA256_Update(&ctx_, static_cast<const unsigned char*>(input), len);
  35   }
  36
  37   virtual void Finish(void* output, size_t len) OVERRIDE {
  38     ScopedOpenSSLSafeSizeBuffer<SHA256_DIGEST_LENGTH> result(
  39         static_cast<unsigned char*>(output), len);
  40     SHA256_Final(result.safe_buffer(), &ctx_);
  41   }
  42
  43   virtual bool Serialize(Pickle* pickle) OVERRIDE;
  44   virtual bool Deserialize(PickleIterator* data_iterator) OVERRIDE;
  45
  46  private:
  47   SHA256_CTX ctx_;
  48 };
  49
  50 bool SecureHashSHA256OpenSSL::Serialize(Pickle* pickle) {
  51   if (!pickle)
  52     return false;
  53
  54   if (!pickle->WriteInt(kSecureHashVersion) ||
  55       !pickle->WriteString(kSHA256Descriptor) ||
  56       !pickle->WriteBytes(&ctx_, sizeof(ctx_))) {
  57     return false;
  58   }
  59
  60   return true;
  61 }
  62
  63 bool SecureHashSHA256OpenSSL::Deserialize(PickleIterator* data_iterator) {
  64   if (!data_iterator)
  65     return false;
  66
  67   int version;
  68   if (!data_iterator->ReadInt(&version))
  69     return false;
  70
  71   if (version > kSecureHashVersion)
  72     return false;  // We don't know how to deal with this.
  73
  74   std::string type;
  75   if (!data_iterator->ReadString(&type))
  76     return false;
  77
  78   if (type != kSHA256Descriptor)
  79     return false;  // It's the wrong kind.
  80
  81   const char* data = NULL;
  82   if (!data_iterator->ReadBytes(&data, sizeof(ctx_)))
  83     return false;
  84
  85   memcpy(&ctx_, data, sizeof(ctx_));
  86
  87   return true;
  88 }
  89
  90 }  // namespace
  91
  92 SecureHash* SecureHash::Create(Algorithm algorithm) {
  93   switch (algorithm) {
  94     case SHA256:
  95       return new SecureHashSHA256OpenSSL();
  96     default:
  97       NOTIMPLEMENTED();
  98       return NULL;
  99   }
 100 }
 101
 102 }  // namespace crypto