util.c revision 1.39
1/* $OpenBSD: util.c,v 1.39 2016/03/20 02:29:51 guenther Exp $ */ 2 3/* 4 * Copyright (c) 1998 Per Fogelstrom, Opsycon AB 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 */ 28 29#include <sys/types.h> 30#include "archdep.h" 31#include "resolve.h" 32 33/* 34 * Stack protector dummies. 35 * Ideally, a scheme to compile these stubs from libc should be used, but 36 * this would end up dragging too much code from libc here. 37 */ 38long __guard_local __dso_hidden __attribute__((section(".openbsd.randomdata"))); 39 40void __stack_smash_handler(char [], int); 41 42void 43__stack_smash_handler(char func[], int damaged) 44{ 45 char message[256]; 46 47 /* <10> indicates LOG_CRIT */ 48 _dl_strlcpy(message, "<10>ld.so:", sizeof message); 49 _dl_strlcat(message, __progname, sizeof message); 50 if (_dl_strlen(message) > sizeof(message)/2) 51 _dl_strlcpy(message + sizeof(message)/2, "...", 52 sizeof(message) - sizeof(message)/2); 53 _dl_strlcat(message, "stack overflow in function ", sizeof message); 54 _dl_strlcat(message, func, sizeof message); 55 56 _dl_sendsyslog(message, _dl_strlen(message)); 57 _dl_exit(127); 58} 59 60char * 61_dl_strdup(const char *orig) 62{ 63 char *newstr; 64 size_t len; 65 66 len = _dl_strlen(orig)+1; 67 newstr = _dl_malloc(len); 68 if (newstr != NULL) 69 _dl_strlcpy(newstr, orig, len); 70 return (newstr); 71} 72 73void 74_dl_randombuf(void *v, size_t buflen) 75{ 76 char *buf = v; 77 size_t chunk; 78 79 while (buflen != 0) { 80 if (buflen > 256) 81 chunk = 256; 82 else 83 chunk = buflen; 84 if (_dl_getentropy(buf, chunk) != 0) 85 _dl_exit(8); 86 buflen -= chunk; 87 buf += chunk; 88 } 89} 90 91u_int32_t 92_dl_random(void) 93{ 94 u_int32_t rnd; 95 _dl_randombuf(&rnd, sizeof(rnd)); 96 return (rnd); 97} 98