1 /*- 2 * Copyright (c) 2003-2007 Tim Kientzle 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "archive_platform.h" 27 __FBSDID("$FreeBSD: src/lib/libarchive/archive_check_magic.c,v 1.9 2008/12/06 05:52:01 kientzle Exp $"); 28 29 #ifdef HAVE_SYS_TYPES_H 30 #include <sys/types.h> 31 #endif 32 33 #include <stdio.h> 34 #ifdef HAVE_STDLIB_H 35 #include <stdlib.h> 36 #endif 37 #ifdef HAVE_STRING_H 38 #include <string.h> 39 #endif 40 #ifdef HAVE_UNISTD_H 41 #include <unistd.h> 42 #endif 43 #if defined(_WIN32) && !defined(__CYGWIN__) 44 #include <windows.h> 45 #include <winbase.h> 46 #endif 47 48 #include "archive_private.h" 49 50 static void 51 errmsg(const char *m) 52 { 53 write(2, m, strlen(m)); 54 } 55 56 static void 57 diediedie(void) 58 { 59 #if defined(_WIN32) && !defined(__CYGWIN__) && defined(_DEBUG) 60 /* Cause a breakpoint exception */ 61 DebugBreak(); 62 #endif 63 *(char *)0 = 1; /* Deliberately segfault and force a coredump. */ 64 _exit(1); /* If that didn't work, just exit with an error. */ 65 } 66 67 static const char * 68 state_name(unsigned s) 69 { 70 switch (s) { 71 case ARCHIVE_STATE_NEW: return ("new"); 72 case ARCHIVE_STATE_HEADER: return ("header"); 73 case ARCHIVE_STATE_DATA: return ("data"); 74 case ARCHIVE_STATE_EOF: return ("eof"); 75 case ARCHIVE_STATE_CLOSED: return ("closed"); 76 case ARCHIVE_STATE_FATAL: return ("fatal"); 77 default: return ("??"); 78 } 79 } 80 81 82 static void 83 write_all_states(unsigned int states) 84 { 85 unsigned int lowbit; 86 87 /* A trick for computing the lowest set bit. */ 88 while ((lowbit = states & (-states)) != 0) { 89 states &= ~lowbit; /* Clear the low bit. */ 90 errmsg(state_name(lowbit)); 91 if (states != 0) 92 errmsg("/"); 93 } 94 } 95 96 /* 97 * Check magic value and current state; bail if it isn't valid. 98 * 99 * This is designed to catch serious programming errors that violate 100 * the libarchive API. 101 */ 102 void 103 __archive_check_magic(struct archive *a, unsigned int magic, 104 unsigned int state, const char *function) 105 { 106 if (a->magic != magic) { 107 errmsg("INTERNAL ERROR: Function "); 108 errmsg(function); 109 errmsg(" invoked with invalid struct archive structure.\n"); 110 diediedie(); 111 } 112 113 if (state == ARCHIVE_STATE_ANY) 114 return; 115 116 if ((a->state & state) == 0) { 117 errmsg("INTERNAL ERROR: Function '"); 118 errmsg(function); 119 errmsg("' invoked with archive structure in state '"); 120 write_all_states(a->state); 121 errmsg("', should be in state '"); 122 write_all_states(state); 123 errmsg("'\n"); 124 diediedie(); 125 } 126 } 127