1 /*- 2 * Copyright (c) 2018 iXsystems, Inc. 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 AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 #include <err.h> 29 #include <getopt.h> 30 #include <libgen.h> 31 #include <stdbool.h> 32 #include <stdio.h> 33 34 #include "cd9660.h" 35 #include "cd9660_eltorito.h" 36 37 #include "etdump.h" 38 39 const char * system_id_string(u_char system_id)40 system_id_string(u_char system_id) 41 { 42 43 switch (system_id) { 44 case ET_SYS_X86: 45 return ("i386"); 46 case ET_SYS_PPC: 47 return ("powerpc"); 48 case ET_SYS_MAC: 49 return ("mac"); 50 case ET_SYS_EFI: 51 return ("efi"); 52 default: 53 return ("invalid"); 54 } 55 } 56 57 const char * media_type_string(u_char media_type)58 media_type_string(u_char media_type) 59 { 60 61 switch (media_type) { 62 case ET_MEDIA_NOEM: 63 return ("no emulation"); 64 case ET_MEDIA_12FDD: 65 return ("1.2MB FDD"); 66 case ET_MEDIA_144FDD: 67 return ("1.44MB FDD"); 68 case ET_MEDIA_288FDD: 69 return ("2.88MB FDD"); 70 case ET_MEDIA_HDD: 71 return ("HDD"); 72 default: 73 return ("invalid"); 74 } 75 } 76 77 static int read_sector(FILE * iso,daddr_t sector,char * buffer)78 read_sector(FILE *iso, daddr_t sector, char *buffer) 79 { 80 81 if (fseek(iso, sector * ISO_DEFAULT_BLOCK_SIZE, SEEK_SET) != 0) { 82 return (errno); 83 } 84 if (fread(buffer, ISO_DEFAULT_BLOCK_SIZE, 1, iso) != 1) { 85 return (errno); 86 } 87 return (0); 88 } 89 90 static bool boot_catalog_valid(char * entry)91 boot_catalog_valid(char *entry) 92 { 93 boot_catalog_validation_entry *ve; 94 int16_t checksum, sum; 95 unsigned char *csptr; 96 size_t i; 97 98 ve = (boot_catalog_validation_entry *)entry; 99 100 checksum = isonum_721(ve->checksum); 101 cd9660_721(0, ve->checksum); 102 csptr = (unsigned char *)ve; 103 104 for (i = sum = 0; i < sizeof(*ve); i += 2) { 105 sum += (int16_t)csptr[i]; 106 sum += 256 * (int16_t)csptr[i + 1]; 107 } 108 if (sum + checksum != 0) { 109 return (false); 110 } 111 112 cd9660_721(checksum, ve->checksum); 113 return (true); 114 } 115 116 static int dump_section(char * buffer,size_t bufsize,size_t offset,FILE * outfile,const char * filename,struct outputter * outputter)117 dump_section(char *buffer, size_t bufsize, size_t offset, FILE *outfile, 118 const char *filename, struct outputter *outputter) 119 { 120 boot_catalog_section_header *sh; 121 u_char platform_id; 122 int i; 123 size_t entry_offset; 124 boot_catalog_section_entry *entry; 125 126 if (offset + sizeof(boot_catalog_section_header) > bufsize) 127 errx(1, "%s: section header out of bounds", filename); 128 sh = (boot_catalog_section_header *)&buffer[offset]; 129 if (outputter->output_section != NULL) { 130 outputter->output_section(outfile, filename, sh); 131 } 132 133 platform_id = sh->platform_id[0]; 134 135 if (outputter->output_entry != NULL) { 136 for (i = 1; i <= (int)sh->num_section_entries[0]; i++) { 137 entry_offset = offset + i * ET_BOOT_ENTRY_SIZE; 138 if (entry_offset + sizeof(boot_catalog_section_entry) > 139 bufsize) 140 errx(1, "%s: section entry out of bounds", 141 filename); 142 entry = 143 (boot_catalog_section_entry *)&buffer[entry_offset]; 144 outputter->output_entry(outfile, filename, entry, 145 platform_id, false); 146 } 147 } 148 149 return (1 + (int)sh->num_section_entries[0]); 150 } 151 152 static void dump_eltorito(FILE * iso,const char * filename,FILE * outfile,struct outputter * outputter)153 dump_eltorito(FILE *iso, const char *filename, FILE *outfile, 154 struct outputter *outputter) 155 { 156 char buffer[ISO_DEFAULT_BLOCK_SIZE], *entry; 157 boot_volume_descriptor *bvd; 158 daddr_t boot_catalog; 159 size_t offset; 160 int entry_count; 161 162 if (read_sector(iso, 17, buffer) != 0) 163 err(1, "failed to read from image"); 164 165 bvd = (boot_volume_descriptor *)buffer; 166 if (memcmp(bvd->identifier, ISO_VOLUME_DESCRIPTOR_STANDARD_ID, 5) != 0) 167 warnx("%s: not a valid ISO", filename); 168 if (bvd->boot_record_indicator[0] != ISO_VOLUME_DESCRIPTOR_BOOT || 169 memcmp(bvd->boot_system_identifier, ET_ID, 23) != 0) 170 warnx("%s: not an El Torito bootable ISO", filename); 171 172 boot_catalog = isonum_731(bvd->boot_catalog_pointer); 173 174 if (read_sector(iso, boot_catalog, buffer) != 0) 175 err(1, "failed to read from image"); 176 177 entry = buffer; 178 offset = 0; 179 180 if (!boot_catalog_valid(entry)) 181 warnx("%s: boot catalog checksum is invalid", filename); 182 183 if (outputter->output_image != NULL) 184 outputter->output_image(outfile, filename, bvd); 185 186 offset += ET_BOOT_ENTRY_SIZE; 187 entry = &buffer[offset]; 188 if (outputter->output_entry != NULL) 189 outputter->output_entry(outfile, filename, 190 (boot_catalog_section_entry *)entry, 0, true); 191 192 offset += ET_BOOT_ENTRY_SIZE; 193 194 while (offset < ISO_DEFAULT_BLOCK_SIZE) { 195 entry = &buffer[offset]; 196 197 if ((uint8_t)entry[0] != ET_SECTION_HEADER_MORE && 198 (uint8_t)entry[0] != ET_SECTION_HEADER_LAST) 199 break; 200 201 entry_count = dump_section(buffer, sizeof(buffer), offset, 202 outfile, filename, outputter); 203 204 offset += entry_count * ET_BOOT_ENTRY_SIZE; 205 } 206 } 207 208 static void usage(const char * progname)209 usage(const char *progname) 210 { 211 char *path; 212 213 path = strdup(progname); 214 215 fprintf(stderr, "usage: %s [-f format] [-o filename] filename [...]\n", 216 basename(path)); 217 fprintf(stderr, "\tsupported output formats: shell, text\n"); 218 exit(1); 219 } 220 221 int main(int argc,char ** argv)222 main(int argc, char **argv) 223 { 224 int ch, i; 225 FILE *outfile, *iso; 226 struct outputter *outputter; 227 228 outfile = stdout; 229 outputter = output_text; 230 231 static struct option longopts[] = { 232 { "format", required_argument, NULL, 'f' }, 233 { "output", required_argument, NULL, 'o' }, 234 { NULL, 0, NULL, 0 }, 235 }; 236 237 while ((ch = getopt_long(argc, argv, "f:o:", longopts, NULL)) != -1) { 238 switch (ch) { 239 case 'f': 240 if (strcmp(optarg, "shell") == 0) 241 outputter = output_shell; 242 else if (strcmp(optarg, "text") == 0) 243 outputter = output_text; 244 else 245 usage(argv[0]); 246 break; 247 case 'o': 248 if (strcmp(optarg, "-") == 0) { 249 outfile = stdout; 250 } else if ((outfile = fopen(optarg, "w")) == NULL) { 251 err(1, "unable to open %s for output", optarg); 252 } 253 break; 254 default: 255 usage(argv[0]); 256 } 257 } 258 259 argc -= optind; 260 argv += optind; 261 262 for (i = 0; i < argc; i++) { 263 if (strcmp(argv[i], "-") == 0) { 264 iso = stdin; 265 } else { 266 iso = fopen(argv[i], "r"); 267 if (iso == NULL) 268 err(1, "could not open %s", argv[i]); 269 } 270 dump_eltorito(iso, argv[i], outfile, outputter); 271 } 272 } 273