minix/lib/libc/misc/stack_protector.c
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

132 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];
size_t len;
#endif
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();
}