2cf5e9365d
According to style(9): > normally, include <sys/types.h> OR <sys/param.h>, but not both. (<sys/param.h> already includes <sys/types.h> when LOCORE is not defined).
117 lines
3.5 KiB
C
117 lines
3.5 KiB
C
/* $NetBSD: stack_protector.c,v 1.4 2006/11/22 17:23:25 christos Exp $ */
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/* $OpenBSD: stack_protector.c,v 1.10 2006/03/31 05:34:44 deraadt Exp $ */
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/*
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* Copyright (c) 2002 Hiroaki Etoh, Federico G. Schwindt, and Miodrag Vallat.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT,
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* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/sysctl.h>
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#include <errno.h>
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#include <link.h>
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#include <signal.h>
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#include <string.h>
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#include <syslog.h>
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#include <unistd.h>
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#include "libc_private.h"
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extern int __sysctl(const int *name, u_int namelen, void *oldp,
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size_t *oldlenp, void *newp, size_t newlen);
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long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0};
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static void __guard_setup(void) __attribute__((__constructor__, __used__));
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static void __fail(const char *);
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void __stack_chk_fail(void);
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void __chk_fail(void);
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/*LINTED used*/
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static void
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__guard_setup(void)
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{
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static const int mib[2] = { CTL_KERN, KERN_ARND };
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size_t len;
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int error;
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if (__stack_chk_guard[0] != 0)
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return;
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error = _elf_aux_info(AT_CANARY, __stack_chk_guard,
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sizeof(__stack_chk_guard));
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if (error == 0 && __stack_chk_guard[0] != 0)
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return;
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len = sizeof(__stack_chk_guard);
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if (__sysctl(mib, nitems(mib), __stack_chk_guard, &len, NULL, 0) ==
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-1 || len != sizeof(__stack_chk_guard)) {
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/* If sysctl was unsuccessful, use the "terminator canary". */
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((unsigned char *)(void *)__stack_chk_guard)[0] = 0;
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((unsigned char *)(void *)__stack_chk_guard)[1] = 0;
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((unsigned char *)(void *)__stack_chk_guard)[2] = '\n';
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((unsigned char *)(void *)__stack_chk_guard)[3] = 255;
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}
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}
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/*ARGSUSED*/
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static void
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__fail(const char *msg)
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{
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struct sigaction sa;
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sigset_t mask;
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/* Immediately block all signal handlers from running code */
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(void)sigfillset(&mask);
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(void)sigdelset(&mask, SIGABRT);
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(void)sigprocmask(SIG_BLOCK, &mask, NULL);
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/* This may fail on a chroot jail... */
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syslog(LOG_CRIT, "%s", msg);
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(void)memset(&sa, 0, sizeof(sa));
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(void)sigemptyset(&sa.sa_mask);
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sa.sa_flags = 0;
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sa.sa_handler = SIG_DFL;
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(void)sigaction(SIGABRT, &sa, NULL);
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(void)kill(getpid(), SIGABRT);
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_exit(127);
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}
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void
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__stack_chk_fail(void)
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{
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__fail("stack overflow detected; terminated");
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}
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void
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__chk_fail(void)
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{
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__fail("buffer overflow detected; terminated");
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}
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#ifndef PIC
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__weak_reference(__stack_chk_fail, __stack_chk_fail_local);
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#endif
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