| // Copyright (c) 2011 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. |
| |
| #include "remoting/host/host_secret.h" |
| |
| #include <string> |
| |
| #include "base/logging.h" |
| #include "base/rand_util.h" |
| #include "base/strings/string_number_conversions.h" |
| |
| namespace remoting { |
| |
| namespace { |
| |
| // 5 digits means 100K possible host secrets with uniform distribution, which |
| // should be enough for short-term passwords, given that we rate-limit guesses |
| // in the cloud and expire access codes after a small number of attempts. |
| const int kHostSecretLength = 5; |
| const char kHostSecretAlphabet[] = "0123456789"; |
| |
| // Generates cryptographically strong random number in the range [0, max). |
| int CryptoRandomInt(int max) { |
| uint32 random_int32; |
| base::RandBytes(&random_int32, sizeof(random_int32)); |
| return random_int32 % max; |
| } |
| |
| } // namespace |
| |
| std::string GenerateSupportHostSecret() { |
| std::string result; |
| int alphabet_size = strlen(kHostSecretAlphabet); |
| result.resize(kHostSecretLength); |
| for (int i = 0; i < kHostSecretLength; ++i) { |
| result[i] = kHostSecretAlphabet[CryptoRandomInt(alphabet_size)]; |
| } |
| return result; |
| } |
| |
| } // namespace remoting |