minix/lib/nbsd_libc/misc/stack_protector.c
Gianluca Guida ad4dda469f Port NetBSD libc functions to Minix.
This patch contains changes to NetBSD libc code base to make it
compile and work on Minix. Some of them are due to actual NetBSD
libc bugs, as we're compiling it in non-reentrant mode and with
a.out support, something not exactly frequent in NetBSD.
Others are proper fixes to port it to Minix (mostly sa_len
parameter missing in socket and a few mmap from files).
2011-02-15 12:19:40 +00:00

131 lines
3.6 KiB
C

/* $NetBSD: stack_protector.c,v 1.5 2010/12/07 20:10:53 joerg Exp $ */
/* $OpenBSD: stack_protector.c,v 1.10 2006/03/31 05:34:44 deraadt Exp $ */
/*
* Copyright (c) 2002 Hiroaki Etoh, Federico G. Schwindt, and Miodrag Vallat.
* 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 AUTHORS ``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 AUTHORS 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 <sys/cdefs.h>
__RCSID("$NetBSD: stack_protector.c,v 1.5 2010/12/07 20:10:53 joerg Exp $");
#ifdef _LIBC
#include "namespace.h"
#endif
#include <sys/param.h>
#include <sys/sysctl.h>
#include <ssp/ssp.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#ifdef _LIBC
#include <syslog.h>
#include "extern.h"
#else
#define __sysctl sysctl
void xprintf(const char *fmt, ...);
#include <stdlib.h>
#endif
long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0};
static void __fail(const char *) __attribute__((__noreturn__));
void __stack_chk_fail_local(void);
void __guard_setup(void);
void
__guard_setup(void)
{
#ifndef __minix
int mib[2];
#endif
size_t len;
if (__stack_chk_guard[0] != 0)
return;
#ifndef __minix
mib[0] = CTL_KERN;
mib[1] = KERN_ARND;
len = sizeof(__stack_chk_guard);
if (__sysctl(mib, 2, __stack_chk_guard, &len, NULL, 0) == -1 ||
len != sizeof(__stack_chk_guard)) {
#endif
/* If sysctl was unsuccessful, use the "terminator canary". */
((unsigned char *)(void *)__stack_chk_guard)[0] = 0;
((unsigned char *)(void *)__stack_chk_guard)[1] = 0;
((unsigned char *)(void *)__stack_chk_guard)[2] = '\n';
((unsigned char *)(void *)__stack_chk_guard)[3] = 255;
#ifndef __minix
}
#endif
}
/*ARGSUSED*/
static void
__fail(const char *msg)
{
#ifdef _LIBC
struct syslog_data sdata = SYSLOG_DATA_INIT;
#endif
struct sigaction sa;
sigset_t mask;
/* Immediately block all signal handlers from running code */
(void)sigfillset(&mask);
(void)sigdelset(&mask, SIGABRT);
(void)sigprocmask(SIG_BLOCK, &mask, NULL);
#ifdef _LIBC
/* This may fail on a chroot jail... */
syslog_ss(LOG_CRIT, &sdata, "%s", msg);
#else
xprintf("%s: %s\n", getprogname(), msg);
#endif
(void)memset(&sa, 0, sizeof(sa));
(void)sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sa.sa_handler = SIG_DFL;
(void)sigaction(SIGABRT, &sa, NULL);
(void)raise(SIGABRT);
_exit(127);
}
void
__stack_chk_fail(void)
{
__fail("stack overflow detected; terminated");
}
void
__chk_fail(void)
{
__fail("buffer overflow detected; terminated");
}
void
__stack_chk_fail_local(void)
{
__stack_chk_fail();
}