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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at */
/* Routines for generating random numbers */
#ifndef mozilla_RandomNum_h_
#define mozilla_RandomNum_h_
#include "mozilla/Maybe.h"
#include "mozilla/Types.h"
namespace mozilla {
* Generate cryptographically secure random bytes using the best facilities
* available on the current OS.
* Return value: true if random bytes were copied into `aBuffer` or false on
* error.
* Useful whenever a secure random number is needed and NSS isn't available.
* (Perhaps because it hasn't been initialized yet)
* Current mechanisms:
* Windows: RtlGenRandom()
* Android, Darwin, DragonFly, FreeBSD, OpenBSD, NetBSD: arc4random()
* Linux: getrandom() if available, "/dev/urandom" otherwise
* Other Unix: "/dev/urandom"
[[nodiscard]] MFBT_API bool GenerateRandomBytesFromOS(void* aBuffer,
size_t aLength);
* Generate a cryptographically secure random 64-bit unsigned number using the
* best facilities available on the current OS.
MFBT_API Maybe<uint64_t> RandomUint64();
* Like RandomUint64, but always returns a uint64_t or crashes with an assert
* if the underlying RandomUint64 call failed.
MFBT_API uint64_t RandomUint64OrDie();
} // namespace mozilla
#endif // mozilla_RandomNum_h_