1 /*        $NetBSD: cd9660.c,v 1.2 2024/05/24 09:59:42 tsutsui Exp $   */
2 
3 /*-
4  * Copyright (c) 2005 Izumi Tsutsui.  All rights reserved.
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 OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #if HAVE_NBTOOL_CONFIG_H
28 #include "nbtool_config.h"
29 #endif
30 
31 #include <sys/cdefs.h>
32 #if defined(__RCSID) && !defined(__lint)
33 __RCSID("$NetBSD: cd9660.c,v 1.2 2024/05/24 09:59:42 tsutsui Exp $");
34 #endif    /* !__lint */
35 
36 #include <sys/param.h>
37 
38 #if !HAVE_NBTOOL_CONFIG_H
39 #include <sys/mount.h>
40 #endif
41 #if !HAVE_NBTOOL_CONFIG_H || HAVE_SYS_ENDIAN_H
42 #include <sys/endian.h>
43 #endif
44 
45 #include <assert.h>
46 #include <err.h>
47 #include <errno.h>
48 #include <fcntl.h>
49 #include <stdarg.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54 #include <dirent.h>
55 
56 #include <fs/cd9660/iso.h>
57 #include <fs/cd9660/cd9660_extern.h>
58 
59 #include "installboot.h"
60 
61 #define roundup(x, y)         ((((x)+((y)-1))/(y))*(y))
62 #define MAXLEN                16
63 
64 
65 int
cd9660_match(ib_params * params)66 cd9660_match(ib_params *params)
67 {
68           int rv, blocksize;
69           struct iso_primary_descriptor ipd;
70 
71           assert(params != NULL);
72           assert(params->fstype != NULL);
73           assert(params->fsfd != -1);
74 
75           rv = pread(params->fsfd, &ipd, sizeof(ipd),
76               ISO_DEFAULT_BLOCK_SIZE * 16);
77           if (rv == -1) {
78                     warn("Reading primary descriptor in `%s'", params->filesystem);
79                     return 0;
80           } else if (rv != sizeof(ipd)) {
81                     warnx("Reading primary descriptor in `%s': short read",
82                        params->filesystem);
83                     return 0;
84           }
85 
86           if (ipd.type[0] != ISO_VD_PRIMARY ||
87               strncmp(ipd.id, ISO_STANDARD_ID, sizeof(ipd.id)) != 0 ||
88               ipd.version[0] != 1) {
89                     warnx("Filesystem `%s' is not ISO9660 format",
90                        params->filesystem);
91                     return 0;
92           }
93 
94           blocksize = isonum_723((u_char *)ipd.logical_block_size);
95           if (blocksize != ISO_DEFAULT_BLOCK_SIZE) {
96                     warnx("Invalid blocksize %d in `%s'",
97                         blocksize, params->filesystem);
98                     return 0;
99           }
100 
101           params->fstype->blocksize = blocksize;
102           params->fstype->needswap = 0;
103 
104           return 1;
105 }
106 
107 int
cd9660_findstage2(ib_params * params,uint32_t * maxblk,ib_block * blocks)108 cd9660_findstage2(ib_params *params, uint32_t *maxblk, ib_block *blocks)
109 {
110           uint8_t buf[ISO_DEFAULT_BLOCK_SIZE];
111           char name[ISO_MAXNAMLEN];
112           char *stage2;
113           off_t loc;
114           int rv, blocksize, found;
115           u_int i;
116           struct iso_primary_descriptor ipd;
117           struct iso_directory_record *idr;
118 
119           assert(params != NULL);
120           assert(params->stage2 != NULL);
121           assert(maxblk != NULL);
122           assert(blocks != NULL);
123 
124 #if 0
125           if (params->flags & IB_STAGE2START)
126                     return hardcode_stage2(params, maxblk, blocks);
127 #endif
128 
129           /* The secondary bootstrap must be clearly in /. */
130           strlcpy(name, params->stage2, ISO_MAXNAMLEN);
131           stage2 = name;
132           if (stage2[0] == '/')
133                     stage2++;
134           if (strchr(stage2, '/') != NULL) {
135                     warnx("The secondary bootstrap `%s' must be in / "
136                         "on filesystem `%s'", params->stage2, params->filesystem);
137                     return 0;
138           }
139           if (strchr(stage2, '.') == NULL) {
140                     /*
141                      * XXX should fix isofncmp()?
142                      */
143                     strlcat(name, ".", ISO_MAXNAMLEN);
144           }
145 
146           rv = pread(params->fsfd, &ipd, sizeof(ipd),
147               ISO_DEFAULT_BLOCK_SIZE * 16);
148           if (rv == -1) {
149                     warn("Reading primary descriptor in `%s'", params->filesystem);
150                     return 0;
151           } else if (rv != sizeof(ipd)) {
152                     warnx("Reading primary descriptor in `%s': short read",
153                        params->filesystem);
154                     return 0;
155           }
156           blocksize = isonum_723((u_char *)ipd.logical_block_size);
157 
158           idr = (void *)ipd.root_directory_record;
159           loc = (off_t)isonum_733(idr->extent) * blocksize;
160           rv = pread(params->fsfd, buf, blocksize, loc);
161           if (rv == -1) {
162                     warn("Reading root directory record in `%s'",
163                         params->filesystem);
164                     return 0;
165           } else if (rv != sizeof(ipd)) {
166                     warnx("Reading root directory record in `%s': short read",
167                        params->filesystem);
168                     return 0;
169           }
170 
171           found = 0;
172           for (i = 0; i < blocksize - sizeof(struct iso_directory_record);
173               i += (u_char)idr->length[0]) {
174                     idr = (void *)&buf[i];
175 
176 #ifdef DEBUG
177                     printf("i = %d, idr->length[0] = %3d\n",
178                         i, (u_char)idr->length[0]);
179 #endif
180                     /* check end of entries */
181                     if (idr->length[0] == 0) {
182 #ifdef DEBUG
183                     printf("end of entries\n");
184 #endif
185                               break;
186                     }
187 
188                     if (idr->flags[0] & 2) {
189                               /* skip directory entries */
190 #ifdef DEBUG
191                               printf("skip directory entry\n");
192 #endif
193                               continue;
194                     }
195                     if (idr->name_len[0] == 1 &&
196                         (idr->name[0] == 0 || idr->name[0] == 1)) {
197                               /* skip "." and ".." */
198 #ifdef DEBUG
199                               printf("skip dot dot\n");
200 #endif
201                               continue;
202                     }
203 #ifdef DEBUG
204                     {
205                               int j;
206 
207                               printf("filename:");
208                               for (j = 0; j < isonum_711(idr->name_len); j++)
209                                         printf("%c", idr->name[j]);
210                               printf("\n");
211                     }
212 #endif
213                     if (isofncmp((u_char *)stage2, strlen(stage2),
214                         (u_char *)idr->name,
215                         isonum_711((u_char *)idr->name_len), 0) == 0) {
216                               found = 1;
217                               /* ISO filesystem always has contiguous file blocks */
218                               blocks[0].block = (int64_t)isonum_733(idr->extent);
219                               blocks[0].blocksize =
220                                   roundup(isonum_733(idr->size), blocksize);
221                               *maxblk = 1;
222 #ifdef DEBUG
223                               printf("block = %ld, blocksize = %ld\n",
224                                   (long)blocks[0].block, blocks[0].blocksize);
225 #endif
226                               break;
227                     }
228           }
229 
230           if (found == 0) {
231                     warnx("Can't find secondary bootstrap `%s' in filesystem `%s'",
232                         params->stage2, params->filesystem);
233                     return 0;
234           }
235 
236           return 1;
237 }
238