| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef SYNC_UTIL_NIGORI_H_ |
| #define SYNC_UTIL_NIGORI_H_ |
| #pragma once |
| |
| #include <string> |
| |
| #include "base/memory/scoped_ptr.h" |
| #include "crypto/symmetric_key.h" |
| |
| namespace browser_sync { |
| |
| // A (partial) implementation of Nigori, a protocol to securely store secrets in |
| // the cloud. This implementation does not support server authentication or |
| // assisted key derivation. |
| // |
| // To store secrets securely, use the |Permute| method to derive a lookup name |
| // for your secret (basically a map key), and |Encrypt| and |Decrypt| to store |
| // and retrieve the secret. |
| // |
| // TODO: Link to doc. |
| class Nigori { |
| public: |
| enum Type { |
| Password = 1, |
| }; |
| |
| Nigori(); |
| virtual ~Nigori(); |
| |
| // Initialize the client with the given |hostname|, |username| and |password|. |
| bool InitByDerivation(const std::string& hostname, |
| const std::string& username, |
| const std::string& password); |
| |
| // Initialize the client by importing the given keys instead of deriving new |
| // ones. |
| bool InitByImport(const std::string& user_key, |
| const std::string& encryption_key, |
| const std::string& mac_key); |
| |
| // Derives a secure lookup name from |type| and |name|. If |hostname|, |
| // |username| and |password| are kept constant, a given |type| and |name| pair |
| // always yields the same |permuted| value. Note that |permuted| will be |
| // Base64 encoded. |
| bool Permute(Type type, const std::string& name, std::string* permuted) const; |
| |
| // Encrypts |value|. Note that on success, |encrypted| will be Base64 |
| // encoded. |
| bool Encrypt(const std::string& value, std::string* encrypted) const; |
| |
| // Decrypts |value| into |decrypted|. It is assumed that |value| is Base64 |
| // encoded. |
| bool Decrypt(const std::string& value, std::string* decrypted) const; |
| |
| // Exports the raw derived keys. |
| bool ExportKeys(std::string* user_key, |
| std::string* encryption_key, |
| std::string* mac_key) const; |
| |
| static const char kSaltSalt[]; // The salt used to derive the user salt. |
| static const size_t kSaltKeySizeInBits = 128; |
| static const size_t kDerivedKeySizeInBits = 128; |
| static const size_t kIvSize = 16; |
| static const size_t kHashSize = 32; |
| |
| static const size_t kSaltIterations = 1001; |
| static const size_t kUserIterations = 1002; |
| static const size_t kEncryptionIterations = 1003; |
| static const size_t kSigningIterations = 1004; |
| |
| private: |
| scoped_ptr<crypto::SymmetricKey> user_key_; |
| scoped_ptr<crypto::SymmetricKey> encryption_key_; |
| scoped_ptr<crypto::SymmetricKey> mac_key_; |
| }; |
| |
| } // namespace browser_sync |
| |
| #endif // SYNC_UTIL_NIGORI_H_ |