/* * Copyright 2004 The WebRTC Project Authors. All rights reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ #ifndef RTC_BASE_CRYPTO_RANDOM_H_ #define RTC_BASE_CRYPTO_RANDOM_H_ #include <stddef.h> #include <stdint.h> #include <memory> #include <string> #include "absl/strings/string_view.h" #include "rtc_base/system/rtc_export.h" namespace rtc { // Interface for RNG implementations. class RandomGenerator { … }; // Sets the default random generator as the source of randomness. The default // source uses the OpenSSL RNG and provides cryptographically secure randomness. void SetDefaultRandomGenerator(); // Set a custom random generator. Results produced by CreateRandomXyz // are cryptographically random iff the output of the supplied generator is // cryptographically random. void SetRandomGenerator(std::unique_ptr<RandomGenerator> generator); // For testing, we can return predictable data. void SetRandomTestMode(bool test); // Initializes the RNG, and seeds it with the specified entropy. bool InitRandom(int seed); bool InitRandom(const char* seed, size_t len); // Generates a (cryptographically) random string of the given length. // We generate base64 values so that they will be printable. RTC_EXPORT std::string CreateRandomString(size_t length); // Generates a (cryptographically) random string of the given length. // We generate base64 values so that they will be printable. // Return false if the random number generator failed. RTC_EXPORT bool CreateRandomString(size_t length, std::string* str); // Generates a (cryptographically) random string of the given length, // with characters from the given table. Return false if the random // number generator failed. // For ease of implementation, the function requires that the table // size evenly divide 256; otherwise, it returns false. RTC_EXPORT bool CreateRandomString(size_t length, absl::string_view table, std::string* str); // Generates (cryptographically) random data of the given length. // Return false if the random number generator failed. bool CreateRandomData(size_t length, std::string* data); // Generates a (cryptographically) random UUID version 4 string. std::string CreateRandomUuid(); // Generates a random id. uint32_t CreateRandomId(); // Generates a 64 bit random id. RTC_EXPORT uint64_t CreateRandomId64(); // Generates a random id > 0. uint32_t CreateRandomNonZeroId(); // Generates a random double between 0.0 (inclusive) and 1.0 (exclusive). double CreateRandomDouble(); } // namespace rtc #endif // RTC_BASE_CRYPTO_RANDOM_H_