Files
fido2-manage/src/random.c
2024-05-24 11:46:48 +02:00

84 lines
1.4 KiB
C

/*
* Copyright (c) 2018 Yubico AB. All rights reserved.
* Use of this source code is governed by a BSD-style
* license that can be found in the LICENSE file.
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_SYS_RANDOM_H
#include <sys/random.h>
#endif
#include <fcntl.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "fido.h"
#if defined(_WIN32)
#include <windows.h>
#include <winternl.h>
#include <winerror.h>
#include <stdio.h>
#include <bcrypt.h>
#include <sal.h>
int
fido_get_random(void *buf, size_t len)
{
NTSTATUS status;
status = BCryptGenRandom(NULL, buf, (ULONG)len,
BCRYPT_USE_SYSTEM_PREFERRED_RNG);
if (!NT_SUCCESS(status))
return (-1);
return (0);
}
#elif defined(HAVE_ARC4RANDOM_BUF)
int
fido_get_random(void *buf, size_t len)
{
arc4random_buf(buf, len);
return (0);
}
#elif defined(HAVE_GETRANDOM)
int
fido_get_random(void *buf, size_t len)
{
ssize_t r;
if ((r = getrandom(buf, len, 0)) < 0 || (size_t)r != len)
return (-1);
return (0);
}
#elif defined(HAVE_DEV_URANDOM)
int
fido_get_random(void *buf, size_t len)
{
int fd = -1;
int ok = -1;
ssize_t r;
if ((fd = open(FIDO_RANDOM_DEV, O_RDONLY)) < 0)
goto fail;
if ((r = read(fd, buf, len)) < 0 || (size_t)r != len)
goto fail;
ok = 0;
fail:
if (fd != -1)
close(fd);
return (ok);
}
#else
#error "please provide an implementation of fido_get_random() for your platform"
#endif /* _WIN32 */