You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

273 lines
6.7 KiB

/*-
* Copyright (c) 2014 Michihiro NAKAJIMA
* 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 THE AUTHOR(S) ``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 THE AUTHOR(S) 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 "archive_platform.h"
__FBSDID("$FreeBSD$");
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if !defined(HAVE_ARC4RANDOM_BUF) && (!defined(_WIN32) || defined(__CYGWIN__))
#ifdef HAVE_FCNTL
#include <fcntl.h>
#endif
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_PTHREAD_H
#include <pthread.h>
#endif
static void arc4random_buf(void *, size_t);
#endif /* HAVE_ARC4RANDOM_BUF */
#include "archive.h"
#include "archive_random_private.h"
#if defined(HAVE_WINCRYPT_H) && !defined(__CYGWIN__)
#include <wincrypt.h>
#endif
#ifndef O_CLOEXEC
#define O_CLOEXEC 0
#endif
/*
* Random number generator function.
* This simply calls arc4random_buf function if the platform provides it.
*/
int
archive_random(void *buf, size_t nbytes)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
HCRYPTPROV hProv;
BOOL success;
success = CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL,
CRYPT_VERIFYCONTEXT);
if (!success && GetLastError() == (DWORD)NTE_BAD_KEYSET) {
success = CryptAcquireContext(&hProv, NULL, NULL,
PROV_RSA_FULL, CRYPT_NEWKEYSET);
}
if (success) {
success = CryptGenRandom(hProv, (DWORD)nbytes, (BYTE*)buf);
CryptReleaseContext(hProv, 0);
if (success)
return ARCHIVE_OK;
}
/* TODO: Does this case really happen? */
return ARCHIVE_FAILED;
#else
arc4random_buf(buf, nbytes);
return ARCHIVE_OK;
#endif
}
#if !defined(HAVE_ARC4RANDOM_BUF) && (!defined(_WIN32) || defined(__CYGWIN__))
/* $OpenBSD: arc4random.c,v 1.24 2013/06/11 16:59:50 deraadt Exp $ */
/*
* Copyright (c) 1996, David Mazieres <dm@uun.org>
* Copyright (c) 2008, Damien Miller <djm@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* Arc4 random number generator for OpenBSD.
*
* This code is derived from section 17.1 of Applied Cryptography,
* second edition, which describes a stream cipher allegedly
* compatible with RSA Labs "RC4" cipher (the actual description of
* which is a trade secret). The same algorithm is used as a stream
* cipher called "arcfour" in Tatu Ylonen's ssh package.
*
* RC4 is a registered trademark of RSA Laboratories.
*/
#ifdef __GNUC__
#define inline __inline
#else /* !__GNUC__ */
#define inline
#endif /* !__GNUC__ */
struct arc4_stream {
uint8_t i;
uint8_t j;
uint8_t s[256];
};
#define RANDOMDEV "/dev/urandom"
#define KEYSIZE 128
#ifdef HAVE_PTHREAD_H
static pthread_mutex_t arc4random_mtx = PTHREAD_MUTEX_INITIALIZER;
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx);
#define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx);
#else
#define _ARC4_LOCK()
#define _ARC4_UNLOCK()
#endif
static int rs_initialized;
static struct arc4_stream rs;
static pid_t arc4_stir_pid;
static int arc4_count;
static inline uint8_t arc4_getbyte(void);
static void arc4_stir(void);
static inline void
arc4_init(void)
{
int n;
for (n = 0; n < 256; n++)
rs.s[n] = n;
rs.i = 0;
rs.j = 0;
}
static inline void
arc4_addrandom(u_char *dat, int datlen)
{
int n;
uint8_t si;
rs.i--;
for (n = 0; n < 256; n++) {
rs.i = (rs.i + 1);
si = rs.s[rs.i];
rs.j = (rs.j + si + dat[n % datlen]);
rs.s[rs.i] = rs.s[rs.j];
rs.s[rs.j] = si;
}
rs.j = rs.i;
}
static void
arc4_stir(void)
{
int done, fd, i;
struct {
struct timeval tv;
pid_t pid;
u_char rnd[KEYSIZE];
} rdat;
if (!rs_initialized) {
arc4_init();
rs_initialized = 1;
}
done = 0;
fd = open(RANDOMDEV, O_RDONLY | O_CLOEXEC, 0);
if (fd >= 0) {
if (read(fd, &rdat, KEYSIZE) == KEYSIZE)
done = 1;
(void)close(fd);
}
if (!done) {
(void)gettimeofday(&rdat.tv, NULL);
rdat.pid = getpid();
/* We'll just take whatever was on the stack too... */
}
arc4_addrandom((u_char *)&rdat, KEYSIZE);
/*
* Discard early keystream, as per recommendations in:
* "(Not So) Random Shuffles of RC4" by Ilya Mironov.
* As per the Network Operations Division, cryptographic requirements
* published on wikileaks on March 2017.
*/
for (i = 0; i < 3072; i++)
(void)arc4_getbyte();
arc4_count = 1600000;
}
static void
arc4_stir_if_needed(void)
{
pid_t pid = getpid();
if (arc4_count <= 0 || !rs_initialized || arc4_stir_pid != pid) {
arc4_stir_pid = pid;
arc4_stir();
}
}
static inline uint8_t
arc4_getbyte(void)
{
uint8_t si, sj;
rs.i = (rs.i + 1);
si = rs.s[rs.i];
rs.j = (rs.j + si);
sj = rs.s[rs.j];
rs.s[rs.i] = sj;
rs.s[rs.j] = si;
return (rs.s[(si + sj) & 0xff]);
}
static void
arc4random_buf(void *_buf, size_t n)
{
u_char *buf = (u_char *)_buf;
_ARC4_LOCK();
arc4_stir_if_needed();
while (n--) {
if (--arc4_count <= 0)
arc4_stir();
buf[n] = arc4_getbyte();
}
_ARC4_UNLOCK();
}
#endif /* !HAVE_ARC4RANDOM_BUF */