/* * Distributed under the terms of the GNU Lesser General Public License * $Header: $ * * This is a modified version of Hiroaki Etoh's stack smashing routines * implemented for glibc. * * The following people have contributed input to this code. * Ned Ludd - <solar[@]gentoo.org> * Alexander Gabert - <pappy[@]gentoo.org> * The PaX Team - <pageexec[@]freemail.hu> * Peter S. Mazinger - <ps.m[@]gmx.net> * Yoann Vandoorselaere - <yoann[@]prelude-ids.org> * Robert Connolly - <robert[@]linuxfromscratch.org> * Cory Visi <cory[@]visi.name> * Mike Frysinger <vapier[@]gentoo.org> */ #include <string.h> #include <unistd.h> #include <sys/syslog.h> #include <ssp-internal.h> static __always_inline void block_signals(void) { struct sigaction sa; sigset_t mask; sigfillset(&mask); sigdelset(&mask, SSP_SIGTYPE); /* Block all signal handlers */ __sigprocmask(SIG_BLOCK, &mask, NULL); /* except SSP_SIGTYPE */ /* Make the default handler associated with the signal handler */ __memset(&sa, 0, sizeof(struct sigaction)); sigfillset(&sa.sa_mask); /* Block all signals */ sa.sa_flags = 0; sa.sa_handler = SIG_DFL; SIGACTION(SSP_SIGTYPE, &sa, NULL); } static __always_inline void ssp_write(int fd, const char *msg1, const char *msg2, const char *msg3) { __write(fd, msg1, __strlen(msg1)); __write(fd, msg2, __strlen(msg2)); __write(fd, msg3, __strlen(msg3)); __write(fd, "()\n", 3); openlog("ssp", LOG_CONS | LOG_PID, LOG_USER); syslog(LOG_INFO, "%s%s%s()", msg1, msg2, msg3); closelog(); } static __always_inline void terminate(void) { (void) KILL(GETPID(), SSP_SIGTYPE); EXIT(127); } void attribute_noreturn __stack_smash_handler(char func[], int damaged __attribute__ ((unused))); void attribute_noreturn __stack_smash_handler(char func[], int damaged) { extern char *__progname; static const char message[] = ": stack smashing attack in function "; block_signals(); ssp_write(STDERR_FILENO, __progname, message, func); /* The loop is added only to keep gcc happy. */ while(1) terminate(); } void attribute_noreturn __stack_chk_fail(void) { extern char *__progname; static const char msg1[] = "stack smashing detected: "; static const char msg3[] = " terminated"; block_signals(); ssp_write(STDERR_FILENO, msg1, __progname, msg3); /* The loop is added only to keep gcc happy. */ while(1) terminate(); } #if 0 void attribute_noreturn __chk_fail(void) { extern char *__progname; static const char msg1[] = "buffer overflow detected: "; static const char msg3[] = " terminated"; block_signals(); ssp_write(STDERR_FILENO, msg1, __progname, msg3); /* The loop is added only to keep gcc happy. */ while(1) terminate(); } #endif