crypto_provider.cc revision a794cd60a7339d576ea2eed263a4f0a20fb255af 
1// Copyright (c) 2012 The Chromium OS 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 "shill/crypto_provider.h"
6
7#include <memory>
8
9#include <base/strings/string_util.h>
10
11#include "shill/crypto_des_cbc.h"
12#include "shill/crypto_rot47.h"
13#include "shill/logging.h"
14
15using std::string;
16
17namespace shill {
18
19const char CryptoProvider::kKeyMatterFile[] = "/var/lib/whitelist/owner.key";
20
21CryptoProvider::CryptoProvider(GLib* glib)
22    : glib_(glib),
23      key_matter_file_(kKeyMatterFile) {}
24
25void CryptoProvider::Init() {
26  cryptos_.clear();
27
28  // Register the crypto modules in priority order -- highest priority first.
29  std::unique_ptr<CryptoDESCBC> des_cbc(new CryptoDESCBC(glib_));
30  if (des_cbc->LoadKeyMatter(key_matter_file_)) {
31    cryptos_.push_back(des_cbc.release());
32  }
33  cryptos_.push_back(new CryptoROT47());
34}
35
36string CryptoProvider::Encrypt(const string& plaintext) {
37  for (auto crypto : cryptos_) {
38    string ciphertext;
39    if (crypto->Encrypt(plaintext, &ciphertext)) {
40      const string prefix = crypto->GetID() + ":";
41      return prefix + ciphertext;
42    }
43  }
44  LOG(WARNING) << "Unable to encrypt text, returning as is.";
45  return plaintext;
46}
47
48string CryptoProvider::Decrypt(const string& ciphertext) {
49  for (auto crypto : cryptos_) {
50    const string prefix = crypto->GetID() + ":";
51    if (base::StartsWithASCII(ciphertext, prefix, true)) {
52      string to_decrypt = ciphertext;
53      to_decrypt.erase(0, prefix.size());
54      string plaintext;
55      if (!crypto->Decrypt(to_decrypt, &plaintext)) {
56        LOG(WARNING) << "Crypto module " << crypto->GetID()
57                     << " failed to decrypt.";
58      }
59      return plaintext;
60    }
61  }
62  LOG(WARNING) << "Unable to decrypt text, returning as is.";
63  return ciphertext;
64}
65
66}  // namespace shill
67