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 __FBSDID("$FreeBSD$");
29
30 #include <err.h>
31 #include <getopt.h>
32 #include <libgen.h>
33 #include <stdbool.h>
34 #include <stdio.h>
35
36 #include "cd9660.h"
37 #include "cd9660_eltorito.h"
38
39 #include "etdump.h"
40
41 const char *
system_id_string(u_char system_id)42 system_id_string(u_char system_id)
43 {
44
45 switch (system_id) {
46 case ET_SYS_X86:
47 return ("i386");
48 case ET_SYS_PPC:
49 return ("powerpc");
50 case ET_SYS_MAC:
51 return ("mac");
52 case ET_SYS_EFI:
53 return ("efi");
54 default:
55 return ("invalid");
56 }
57 }
58
59 const char *
media_type_string(u_char media_type)60 media_type_string(u_char media_type)
61 {
62
63 switch (media_type) {
64 case ET_MEDIA_NOEM:
65 return ("no emulation");
66 case ET_MEDIA_12FDD:
67 return ("1.2MB FDD");
68 case ET_MEDIA_144FDD:
69 return ("1.44MB FDD");
70 case ET_MEDIA_288FDD:
71 return ("2.88MB FDD");
72 case ET_MEDIA_HDD:
73 return ("HDD");
74 default:
75 return ("invalid");
76 }
77 }
78
79 static int
read_sector(FILE * iso,daddr_t sector,char * buffer)80 read_sector(FILE *iso, daddr_t sector, char *buffer)
81 {
82
83 if (fseek(iso, sector * ISO_DEFAULT_BLOCK_SIZE, SEEK_SET) != 0) {
84 return (errno);
85 }
86 if (fread(buffer, ISO_DEFAULT_BLOCK_SIZE, 1, iso) != 1) {
87 return (errno);
88 }
89 return (0);
90 }
91
92 static bool
boot_catalog_valid(char * entry)93 boot_catalog_valid(char *entry)
94 {
95 boot_catalog_validation_entry *ve;
96 int16_t checksum, sum;
97 unsigned char *csptr;
98 size_t i;
99
100 ve = (boot_catalog_validation_entry *)entry;
101
102 checksum = isonum_721(ve->checksum);
103 cd9660_721(0, ve->checksum);
104 csptr = (unsigned char *)ve;
105
106 for (i = sum = 0; i < sizeof(*ve); i += 2) {
107 sum += (int16_t)csptr[i];
108 sum += 256 * (int16_t)csptr[i + 1];
109 }
110 if (sum + checksum != 0) {
111 return (false);
112 }
113
114 cd9660_721(checksum, ve->checksum);
115 return (true);
116 }
117
118 static int
dump_section(char * buffer,size_t offset,FILE * outfile,const char * filename,struct outputter * outputter)119 dump_section(char *buffer, size_t offset, FILE *outfile, const char *filename,
120 struct outputter *outputter)
121 {
122 boot_catalog_section_header *sh;
123 u_char platform_id;
124 int i;
125 size_t entry_offset;
126 boot_catalog_section_entry *entry;
127
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 entry =
139 (boot_catalog_section_entry *)&buffer[entry_offset];
140 outputter->output_entry(outfile, filename, entry,
141 platform_id, false);
142 }
143 }
144
145 return (1 + (int)sh->num_section_entries[0]);
146 }
147
148 static void
dump_eltorito(FILE * iso,const char * filename,FILE * outfile,struct outputter * outputter)149 dump_eltorito(FILE *iso, const char *filename, FILE *outfile,
150 struct outputter *outputter)
151 {
152 char buffer[ISO_DEFAULT_BLOCK_SIZE], *entry;
153 boot_volume_descriptor *bvd;
154 daddr_t boot_catalog;
155 size_t offset;
156 int entry_count;
157
158 if (read_sector(iso, 17, buffer) != 0)
159 err(1, "failed to read from image");
160
161 bvd = (boot_volume_descriptor *)buffer;
162 if (memcmp(bvd->identifier, ISO_VOLUME_DESCRIPTOR_STANDARD_ID, 5) != 0)
163 warnx("%s: not a valid ISO", filename);
164 if (bvd->boot_record_indicator[0] != ISO_VOLUME_DESCRIPTOR_BOOT)
165 warnx("%s: not an El Torito bootable ISO", filename);
166 if (memcmp(bvd->boot_system_identifier, ET_ID, 23) != 0)
167 warnx("%s: not an El Torito bootable ISO", filename);
168
169 boot_catalog = isonum_731(bvd->boot_catalog_pointer);
170
171 if (read_sector(iso, boot_catalog, buffer) != 0)
172 err(1, "failed to read from image");
173
174 entry = buffer;
175 offset = 0;
176
177 if (!boot_catalog_valid(entry))
178 warnx("%s: boot catalog checksum is invalid", filename);
179
180 if (outputter->output_image != NULL)
181 outputter->output_image(outfile, filename, bvd);
182
183 offset += ET_BOOT_ENTRY_SIZE;
184 entry = &buffer[offset];
185 if (outputter->output_entry != NULL)
186 outputter->output_entry(outfile, filename,
187 (boot_catalog_section_entry *)entry, 0, true);
188
189 offset += ET_BOOT_ENTRY_SIZE;
190
191 while (offset < ISO_DEFAULT_BLOCK_SIZE) {
192 entry = &buffer[offset];
193
194 if ((uint8_t)entry[0] != ET_SECTION_HEADER_MORE &&
195 (uint8_t)entry[0] != ET_SECTION_HEADER_LAST)
196 break;
197
198 entry_count = dump_section(buffer, offset, outfile, filename,
199 outputter);
200
201 offset += entry_count * ET_BOOT_ENTRY_SIZE;
202 }
203 }
204
205 static void
usage(const char * progname)206 usage(const char *progname)
207 {
208 char *path;
209
210 path = strdup(progname);
211
212 fprintf(stderr, "usage: %s [-f format] [-o filename] filename [...]\n",
213 basename(path));
214 fprintf(stderr, "\tsupported output formats: shell, text\n");
215 exit(1);
216 }
217
218 int
main(int argc,char ** argv)219 main(int argc, char **argv)
220 {
221 int ch, i;
222 FILE *outfile, *iso;
223 struct outputter *outputter;
224
225 outfile = stdout;
226 outputter = output_text;
227
228 static struct option longopts[] = {
229 { "format", required_argument, NULL, 'f' },
230 { "output", required_argument, NULL, 'o' },
231 { NULL, 0, NULL, 0 },
232 };
233
234 while ((ch = getopt_long(argc, argv, "f:o:", longopts, NULL)) != -1) {
235 switch (ch) {
236 case 'f':
237 if (strcmp(optarg, "shell") == 0)
238 outputter = output_shell;
239 else if (strcmp(optarg, "text") == 0)
240 outputter = output_text;
241 else
242 usage(argv[0]);
243 break;
244 case 'o':
245 if (strcmp(optarg, "-") == 0) {
246 outfile = stdout;
247 } else if ((outfile = fopen(optarg, "w")) == NULL) {
248 err(1, "unable to open %s for output", optarg);
249 }
250 break;
251 default:
252 usage(argv[0]);
253 }
254 }
255
256 argc -= optind;
257 argv += optind;
258
259 for (i = 0; i < argc; i++) {
260 if (strcmp(argv[i], "-") == 0) {
261 iso = stdin;
262 } else {
263 iso = fopen(argv[i], "r");
264 if (iso == NULL)
265 err(1, "could not open %s", argv[i]);
266 }
267 dump_eltorito(iso, argv[i], outfile, outputter);
268 }
269 }
270