cd9660.c revision 1.23 1 /* $NetBSD: cd9660.c,v 1.23 2007/11/24 13:20:54 isaki Exp $ */
2
3 /*
4 * Copyright (C) 1996 Wolfgang Solfrank.
5 * Copyright (C) 1996 TooLs GmbH.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by TooLs GmbH.
19 * 4. The name of TooLs GmbH may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
28 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34 /*
35 * Stand-alone ISO9660 file reading package.
36 *
37 * Note: This doesn't support Rock Ridge extensions, extended attributes,
38 * blocksizes other than 2048 bytes, multi-extent files, etc.
39 */
40 #include <sys/param.h>
41 #ifdef _STANDALONE
42 #include <lib/libkern/libkern.h>
43 #else
44 #include <string.h>
45 #endif
46 #include <fs/cd9660/iso.h>
47
48 #include "stand.h"
49 #include "cd9660.h"
50
51 /*
52 * XXX Does not currently implement:
53 * XXX
54 * XXX LIBSA_NO_FS_SYMLINK (does this even make sense?)
55 * XXX LIBSA_FS_SINGLECOMPONENT
56 */
57
58 struct file {
59 off_t off; /* Current offset within file */
60 daddr_t bno; /* Starting block number */
61 off_t size; /* Size of file */
62 };
63
64 struct ptable_ent {
65 char namlen [ISODCL( 1, 1)]; /* 711 */
66 char extlen [ISODCL( 2, 2)]; /* 711 */
67 char block [ISODCL( 3, 6)]; /* 732 */
68 char parent [ISODCL( 7, 8)]; /* 722 */
69 char name [1];
70 };
71 #define PTFIXSZ 8
72 #define PTSIZE(pp) roundup(PTFIXSZ + isonum_711((pp)->namlen), 2)
73
74 #define cdb2devb(bno) ((bno) * ISO_DEFAULT_BLOCK_SIZE / DEV_BSIZE)
75
76 static int pnmatch(const char *, struct ptable_ent *);
77 static int dirmatch(const char *, struct iso_directory_record *);
78
79 static int
80 pnmatch(const char *path, struct ptable_ent *pp)
81 {
82 char *cp;
83 int i;
84
85 cp = pp->name;
86 for (i = isonum_711(pp->namlen); --i >= 0; path++, cp++) {
87 if (toupper(*path) == *cp)
88 continue;
89 return 0;
90 }
91 if (*path != '/')
92 return 0;
93 return 1;
94 }
95
96 static int
97 dirmatch(const char *path, struct iso_directory_record *dp)
98 {
99 char *cp;
100 int i;
101
102 /* This needs to be a regular file */
103 if (dp->flags[0] & 6)
104 return 0;
105
106 cp = dp->name;
107 for (i = isonum_711(dp->name_len); --i >= 0; path++, cp++) {
108 if (!*path)
109 break;
110 if (toupper(*path) == *cp)
111 continue;
112 return 0;
113 }
114 if (*path)
115 return 0;
116 /*
117 * Allow stripping of trailing dots and the version number.
118 * Note that this will find the first instead of the last version
119 * of a file.
120 */
121 if (i >= 0 && (*cp == ';' || *cp == '.')) {
122 /* This is to prevent matching of numeric extensions */
123 if (*cp == '.' && cp[1] != ';')
124 return 0;
125 while (--i >= 0)
126 if (*++cp != ';' && (*cp < '0' || *cp > '9'))
127 return 0;
128 }
129 return 1;
130 }
131
132 int
133 cd9660_open(const char *path, struct open_file *f)
134 {
135 struct file *fp = 0;
136 void *buf;
137 struct iso_primary_descriptor *vd;
138 size_t buf_size, nread, psize, dsize;
139 daddr_t bno;
140 int parent, ent;
141 struct ptable_ent *pp;
142 struct iso_directory_record *dp = 0;
143 int rc;
144
145 /* First find the volume descriptor */
146 buf_size = ISO_DEFAULT_BLOCK_SIZE;
147 buf = alloc(buf_size);
148 vd = buf;
149 for (bno = 16;; bno++) {
150 #if !defined(LIBSA_NO_TWIDDLE)
151 twiddle();
152 #endif
153 rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
154 ISO_DEFAULT_BLOCK_SIZE, buf, &nread);
155 if (rc)
156 goto out;
157 if (nread != ISO_DEFAULT_BLOCK_SIZE) {
158 rc = EIO;
159 goto out;
160 }
161 rc = EINVAL;
162 if (memcmp(vd->id, ISO_STANDARD_ID, sizeof vd->id) != 0)
163 goto out;
164 if (isonum_711(vd->type) == ISO_VD_END)
165 goto out;
166 if (isonum_711(vd->type) == ISO_VD_PRIMARY)
167 break;
168 }
169 if (isonum_723(vd->logical_block_size) != ISO_DEFAULT_BLOCK_SIZE)
170 goto out;
171
172 /* Now get the path table and lookup the directory of the file */
173 bno = isonum_732(vd->type_m_path_table);
174 psize = isonum_733(vd->path_table_size);
175
176 if (psize > ISO_DEFAULT_BLOCK_SIZE) {
177 dealloc(buf, ISO_DEFAULT_BLOCK_SIZE);
178 buf = alloc(buf_size = roundup(psize, ISO_DEFAULT_BLOCK_SIZE));
179 }
180
181 #if !defined(LIBSA_NO_TWIDDLE)
182 twiddle();
183 #endif
184 rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
185 buf_size, buf, &nread);
186 if (rc)
187 goto out;
188 if (nread != buf_size) {
189 rc = EIO;
190 goto out;
191 }
192
193 parent = 1;
194 pp = (struct ptable_ent *)buf;
195 ent = 1;
196 bno = isonum_732(pp->block) + isonum_711(pp->extlen);
197
198 rc = ENOENT;
199 /*
200 * Remove extra separators
201 */
202 while (*path == '/')
203 path++;
204
205 while (*path) {
206 if ((char *)pp >= (char *)buf + psize)
207 break;
208 if (isonum_722(pp->parent) != parent)
209 break;
210 if (!pnmatch(path, pp)) {
211 pp = (struct ptable_ent *)((char *)pp + PTSIZE(pp));
212 ent++;
213 continue;
214 }
215 path += isonum_711(pp->namlen) + 1;
216 parent = ent;
217 bno = isonum_732(pp->block) + isonum_711(pp->extlen);
218 while ((char *)pp < (char *)buf + psize) {
219 if (isonum_722(pp->parent) == parent)
220 break;
221 pp = (struct ptable_ent *)((char *)pp + PTSIZE(pp));
222 ent++;
223 }
224 }
225
226 /*
227 * Now bno has the start of the directory that supposedly
228 * contains the file
229 */
230 bno--;
231 dsize = 1; /* Something stupid, but > 0 XXX */
232 for (psize = 0; psize < dsize;) {
233 if (!(psize % ISO_DEFAULT_BLOCK_SIZE)) {
234 bno++;
235 #if !defined(LIBSA_NO_TWIDDLE)
236 twiddle();
237 #endif
238 rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
239 cdb2devb(bno),
240 ISO_DEFAULT_BLOCK_SIZE,
241 buf, &nread);
242 if (rc)
243 goto out;
244 if (nread != ISO_DEFAULT_BLOCK_SIZE) {
245 rc = EIO;
246 goto out;
247 }
248 dp = (struct iso_directory_record *)buf;
249 }
250 if (!isonum_711(dp->length)) {
251 if ((void *)dp == buf)
252 psize += ISO_DEFAULT_BLOCK_SIZE;
253 else
254 psize = roundup(psize, ISO_DEFAULT_BLOCK_SIZE);
255 continue;
256 }
257 if (dsize == 1)
258 dsize = isonum_733(dp->size);
259 if (dirmatch(path, dp))
260 break;
261 psize += isonum_711(dp->length);
262 dp = (struct iso_directory_record *)
263 ((char *)dp + isonum_711(dp->length));
264 }
265
266 if (psize >= dsize) {
267 rc = ENOENT;
268 goto out;
269 }
270
271 /* allocate file system specific data structure */
272 fp = alloc(sizeof(struct file));
273 memset(fp, 0, sizeof(struct file));
274 f->f_fsdata = (void *)fp;
275
276 fp->off = 0;
277 fp->bno = isonum_733(dp->extent);
278 fp->size = isonum_733(dp->size);
279 dealloc(buf, buf_size);
280
281 return 0;
282
283 out:
284 if (fp)
285 dealloc(fp, sizeof(struct file));
286 dealloc(buf, buf_size);
287
288 return rc;
289 }
290
291 #if !defined(LIBSA_NO_FS_CLOSE)
292 int
293 cd9660_close(struct open_file *f)
294 {
295 struct file *fp = (struct file *)f->f_fsdata;
296
297 f->f_fsdata = 0;
298 dealloc(fp, sizeof *fp);
299
300 return 0;
301 }
302 #endif /* !defined(LIBSA_NO_FS_CLOSE) */
303
304 int
305 cd9660_read(struct open_file *f, void *start, size_t size, size_t *resid)
306 {
307 struct file *fp = (struct file *)f->f_fsdata;
308 int rc = 0;
309 daddr_t bno;
310 char buf[ISO_DEFAULT_BLOCK_SIZE];
311 char *dp;
312 size_t nread, off;
313
314 while (size) {
315 if (fp->off < 0 || fp->off >= fp->size)
316 break;
317 bno = fp->off / ISO_DEFAULT_BLOCK_SIZE + fp->bno;
318 if (fp->off & (ISO_DEFAULT_BLOCK_SIZE - 1)
319 || size < ISO_DEFAULT_BLOCK_SIZE)
320 dp = buf;
321 else
322 dp = start;
323 #if !defined(LIBSA_NO_TWIDDLE)
324 twiddle();
325 #endif
326 rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
327 ISO_DEFAULT_BLOCK_SIZE, dp, &nread);
328 if (rc)
329 return rc;
330 if (nread != ISO_DEFAULT_BLOCK_SIZE)
331 return EIO;
332 if (dp == buf) {
333 off = fp->off & (ISO_DEFAULT_BLOCK_SIZE - 1);
334 if (nread > off + size)
335 nread = off + size;
336 nread -= off;
337 memcpy(start, buf + off, nread);
338 start = (char *)start + nread;
339 fp->off += nread;
340 size -= nread;
341 } else {
342 start = (char *)start + ISO_DEFAULT_BLOCK_SIZE;
343 fp->off += ISO_DEFAULT_BLOCK_SIZE;
344 size -= ISO_DEFAULT_BLOCK_SIZE;
345 }
346 }
347 if (resid)
348 *resid = size;
349 return rc;
350 }
351
352 #if !defined(LIBSA_NO_FS_WRITE)
353 int
354 cd9660_write(struct open_file *f, void *start, size_t size, size_t *resid)
355 {
356
357 return EROFS;
358 }
359 #endif /* !defined(LIBSA_NO_FS_WRITE) */
360
361 #if !defined(LIBSA_NO_FS_SEEK)
362 off_t
363 cd9660_seek(struct open_file *f, off_t offset, int where)
364 {
365 struct file *fp = (struct file *)f->f_fsdata;
366
367 switch (where) {
368 case SEEK_SET:
369 fp->off = offset;
370 break;
371 case SEEK_CUR:
372 fp->off += offset;
373 break;
374 case SEEK_END:
375 fp->off = fp->size - offset;
376 break;
377 default:
378 return -1;
379 }
380 return fp->off;
381 }
382 #endif /* !defined(LIBSA_NO_FS_SEEK) */
383
384 int
385 cd9660_stat(struct open_file *f, struct stat *sb)
386 {
387 struct file *fp = (struct file *)f->f_fsdata;
388
389 /* only importatn stuff */
390 sb->st_mode = S_IFREG | S_IRUSR | S_IRGRP | S_IROTH;
391 sb->st_uid = sb->st_gid = 0;
392 sb->st_size = fp->size;
393 return 0;
394 }
395