1 /* $NetBSD: unzcrash.c,v 1.1.1.2 2012/05/07 00:41:46 wiz Exp $ */ 2 3 4 /* A test program written to test robustness to decompression of 5 corrupted data. Usage is 6 unzcrash filename 7 and the program will read the specified file, compress it (in memory), 8 and then repeatedly decompress it, each time with a different bit of 9 the compressed data inverted, so as to test all possible one-bit errors. 10 This should not cause any invalid memory accesses. If it does, 11 I want to know about it! 12 13 PS. As you can see from the above description, the process is 14 incredibly slow. A file of size eg 5KB will cause it to run for 15 many hours. 16 */ 17 18 /* ------------------------------------------------------------------ 19 This file is part of bzip2/libbzip2, a program and library for 20 lossless, block-sorting data compression. 21 22 bzip2/libbzip2 version 1.0.6 of 6 September 2010 23 Copyright (C) 1996-2010 Julian Seward <jseward@bzip.org> 24 25 Please read the WARNING, DISCLAIMER and PATENTS sections in the 26 README file. 27 28 This program is released under the terms of the license contained 29 in the file LICENSE. 30 ------------------------------------------------------------------ */ 31 32 33 #include <stdio.h> 34 #include <assert.h> 35 #include "bzlib.h" 36 37 #define M_BLOCK 1000000 38 39 typedef unsigned char uchar; 40 41 #define M_BLOCK_OUT (M_BLOCK + 1000000) 42 uchar inbuf[M_BLOCK]; 43 uchar outbuf[M_BLOCK_OUT]; 44 uchar zbuf[M_BLOCK + 600 + (M_BLOCK / 100)]; 45 46 int nIn, nOut, nZ; 47 48 static char *bzerrorstrings[] = { 49 "OK" 50 ,"SEQUENCE_ERROR" 51 ,"PARAM_ERROR" 52 ,"MEM_ERROR" 53 ,"DATA_ERROR" 54 ,"DATA_ERROR_MAGIC" 55 ,"IO_ERROR" 56 ,"UNEXPECTED_EOF" 57 ,"OUTBUFF_FULL" 58 ,"???" /* for future */ 59 ,"???" /* for future */ 60 ,"???" /* for future */ 61 ,"???" /* for future */ 62 ,"???" /* for future */ 63 ,"???" /* for future */ 64 }; 65 66 void flip_bit ( int bit ) 67 { 68 int byteno = bit / 8; 69 int bitno = bit % 8; 70 uchar mask = 1 << bitno; 71 //fprintf ( stderr, "(byte %d bit %d mask %d)", 72 // byteno, bitno, (int)mask ); 73 zbuf[byteno] ^= mask; 74 } 75 76 int main ( int argc, char** argv ) 77 { 78 FILE* f; 79 int r; 80 int bit; 81 int i; 82 83 if (argc != 2) { 84 fprintf ( stderr, "usage: unzcrash filename\n" ); 85 return 1; 86 } 87 88 f = fopen ( argv[1], "r" ); 89 if (!f) { 90 fprintf ( stderr, "unzcrash: can't open %s\n", argv[1] ); 91 return 1; 92 } 93 94 nIn = fread ( inbuf, 1, M_BLOCK, f ); 95 fprintf ( stderr, "%d bytes read\n", nIn ); 96 97 nZ = M_BLOCK; 98 r = BZ2_bzBuffToBuffCompress ( 99 zbuf, &nZ, inbuf, nIn, 9, 0, 30 ); 100 101 assert (r == BZ_OK); 102 fprintf ( stderr, "%d after compression\n", nZ ); 103 104 for (bit = 0; bit < nZ*8; bit++) { 105 fprintf ( stderr, "bit %d ", bit ); 106 flip_bit ( bit ); 107 nOut = M_BLOCK_OUT; 108 r = BZ2_bzBuffToBuffDecompress ( 109 outbuf, &nOut, zbuf, nZ, 0, 0 ); 110 fprintf ( stderr, " %d %s ", r, bzerrorstrings[-r] ); 111 112 if (r != BZ_OK) { 113 fprintf ( stderr, "\n" ); 114 } else { 115 if (nOut != nIn) { 116 fprintf(stderr, "nIn/nOut mismatch %d %d\n", nIn, nOut ); 117 return 1; 118 } else { 119 for (i = 0; i < nOut; i++) 120 if (inbuf[i] != outbuf[i]) { 121 fprintf(stderr, "mismatch at %d\n", i ); 122 return 1; 123 } 124 if (i == nOut) fprintf(stderr, "really ok!\n" ); 125 } 126 } 127 128 flip_bit ( bit ); 129 } 130 131 #if 0 132 assert (nOut == nIn); 133 for (i = 0; i < nOut; i++) { 134 if (inbuf[i] != outbuf[i]) { 135 fprintf ( stderr, "difference at %d !\n", i ); 136 return 1; 137 } 138 } 139 #endif 140 141 fprintf ( stderr, "all ok\n" ); 142 return 0; 143 } 144