blob: 7d86f6f3f559d3a82d5236e1b4cadba58e33ae94 [file] [log] [blame]
/*
* Copyright (C) 2011 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY GOOGLE, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "OSRandomSource.h"
#include <stdint.h>
#include <stdlib.h>
#if OS(SYMBIAN)
#include <e32math.h>
#endif
#if OS(UNIX)
#include <fcntl.h>
#include <unistd.h>
#endif
#if OS(WINDOWS)
#include <windows.h>
#include <wincrypt.h> // windows.h must be included before wincrypt.h.
#endif
namespace WTF {
#if USE(OS_RANDOMNESS)
void cryptographicallyRandomValuesFromOS(unsigned char* buffer, size_t length)
{
#if OS(SYMBIAN)
TInt random;
while (length > sizeof(random)) {
random = Math::Random();
memcpy(buffer, &random, sizeof(random));
length -= sizeof(random);
buffer += sizeof(random);
}
if (length > 0) {
random = Math::Random();
memcpy(buffer, &random, length);
}
#elif OS(UNIX)
int fd = open("/dev/urandom", O_RDONLY, 0);
if (fd < 0)
CRASH(); // We need /dev/urandom for this API to work...
if (read(fd, buffer, length) != static_cast<ssize_t>(length))
CRASH();
close(fd);
#elif OS(WINDOWS)
HCRYPTPROV hCryptProv = 0;
if (!CryptAcquireContext(&hCryptProv, 0, MS_DEF_PROV, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT))
CRASH();
if (!CryptGenRandom(hCryptProv, length, buffer))
CRASH();
CryptReleaseContext(hCryptProv, 0);
#else
#error "This configuration doesn't have a strong source of randomness."
// WARNING: When adding new sources of OS randomness, the randomness must
// be of cryptographic quality!
#endif
}
#endif
}