1 //
2 // Copyright (C) 2012 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 // http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16
17 #include "shill/crypto_provider.h"
18
19 #include <memory>
20
21 #include <base/strings/string_util.h>
22
23 #include "shill/crypto_des_cbc.h"
24 #include "shill/crypto_rot47.h"
25 #include "shill/logging.h"
26
27 using std::string;
28
29 namespace shill {
30
31 const char CryptoProvider::kKeyMatterFile[] = "/var/lib/whitelist/owner.key";
32
CryptoProvider()33 CryptoProvider::CryptoProvider()
34 : key_matter_file_(kKeyMatterFile) {}
35
Init()36 void CryptoProvider::Init() {
37 cryptos_.clear();
38
39 // Register the crypto modules in priority order -- highest priority first.
40 std::unique_ptr<CryptoDESCBC> des_cbc(new CryptoDESCBC());
41 if (des_cbc->LoadKeyMatter(key_matter_file_)) {
42 cryptos_.push_back(des_cbc.release());
43 }
44 cryptos_.push_back(new CryptoROT47());
45 }
46
Encrypt(const string & plaintext)47 string CryptoProvider::Encrypt(const string& plaintext) {
48 for (auto crypto : cryptos_) {
49 string ciphertext;
50 if (crypto->Encrypt(plaintext, &ciphertext)) {
51 const string prefix = crypto->GetID() + ":";
52 return prefix + ciphertext;
53 }
54 }
55 LOG(WARNING) << "Unable to encrypt text, returning as is.";
56 return plaintext;
57 }
58
Decrypt(const string & ciphertext)59 string CryptoProvider::Decrypt(const string& ciphertext) {
60 for (auto crypto : cryptos_) {
61 const string prefix = crypto->GetID() + ":";
62 if (base::StartsWith(ciphertext, prefix, base::CompareCase::SENSITIVE)) {
63 string to_decrypt = ciphertext;
64 to_decrypt.erase(0, prefix.size());
65 string plaintext;
66 if (!crypto->Decrypt(to_decrypt, &plaintext)) {
67 LOG(WARNING) << "Crypto module " << crypto->GetID()
68 << " failed to decrypt.";
69 }
70 return plaintext;
71 }
72 }
73 LOG(WARNING) << "Unable to decrypt text, returning as is.";
74 return ciphertext;
75 }
76
77 } // namespace shill
78