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sys/stack_protector-obsd.c /dev/null Libc-498.1.1
--- /dev/null
+++ Libc/Libc-498.1.1/sys/stack_protector-obsd.c
@@ -0,0 +1,72 @@
+/*
+ * 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.
+ *
+ */
+
+#if defined(LIBC_SCCS) && !defined(list)
+static char rcsid[] = "$OpenBSD: stack_protector.c,v 1.3 2002/12/10 08:53:42 etoh Exp $";
+#endif
+
+#include <sys/param.h>
+#include <sys/sysctl.h>
+#include <syslog.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+extern void __abort(void) __dead2;
+long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+void __guard_setup(void) __attribute__ ((visibility ("hidden")));
+void __stack_chk_fail(void);
+
+void
+__guard_setup(void)
+{
+  int fd;
+  if (__stack_chk_guard[0]!=0) return;
+  fd = open ("/dev/urandom", 0);
+  if (fd != -1) {
+    ssize_t size = read (fd, (char*)&__stack_chk_guard,
+			 sizeof(__stack_chk_guard));
+    close (fd) ;
+    if (size == sizeof(__stack_chk_guard)
+	&& *__stack_chk_guard != 0) return;
+  }
+  /* If a random generator can't be used, the protector switches the guard
+     to the "terminator canary" */
+  ((char*)__stack_chk_guard)[0] = 0; ((char*)__stack_chk_guard)[1] = 0;
+  ((char*)__stack_chk_guard)[2] = '\n'; ((char*)__stack_chk_guard)[3] = 255;
+}
+
+void
+__stack_chk_fail()
+{
+  const char message[] = "[%d] stack overflow";
+
+  /* this may fail on a chroot jail, though luck */
+  syslog(LOG_CRIT, message, getpid());
+
+  __abort();
+}