Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/isofs/rock.c | |
3 | * | |
4 | * (C) 1992, 1993 Eric Youngdale | |
5 | * | |
6 | * Rock Ridge Extensions to iso9660 | |
7 | */ | |
8 | ||
1da177e4 LT |
9 | #include <linux/slab.h> |
10 | #include <linux/pagemap.h> | |
11 | #include <linux/smp_lock.h> | |
1da177e4 | 12 | |
94f2f715 | 13 | #include "isofs.h" |
1da177e4 LT |
14 | #include "rock.h" |
15 | ||
7373909d AM |
16 | /* |
17 | * These functions are designed to read the system areas of a directory record | |
1da177e4 LT |
18 | * and extract relevant information. There are different functions provided |
19 | * depending upon what information we need at the time. One function fills | |
20 | * out an inode structure, a second one extracts a filename, a third one | |
21 | * returns a symbolic link name, and a fourth one returns the extent number | |
7373909d AM |
22 | * for the file. |
23 | */ | |
1da177e4 | 24 | |
1d372116 | 25 | #define SIG(A,B) ((A) | ((B) << 8)) /* isonum_721() */ |
1da177e4 | 26 | |
ba40aaf0 AM |
27 | struct rock_state { |
28 | void *buffer; | |
29 | unsigned char *chr; | |
30 | int len; | |
31 | int cont_size; | |
32 | int cont_extent; | |
33 | int cont_offset; | |
34 | struct inode *inode; | |
35 | }; | |
36 | ||
12121714 AM |
37 | /* |
38 | * This is a way of ensuring that we have something in the system | |
7373909d | 39 | * use fields that is compatible with Rock Ridge. Return zero on success. |
12121714 AM |
40 | */ |
41 | ||
42 | static int check_sp(struct rock_ridge *rr, struct inode *inode) | |
43 | { | |
44 | if (rr->u.SP.magic[0] != 0xbe) | |
45 | return -1; | |
46 | if (rr->u.SP.magic[1] != 0xef) | |
47 | return -1; | |
48 | ISOFS_SB(inode->i_sb)->s_rock_offset = rr->u.SP.skip; | |
49 | return 0; | |
50 | } | |
51 | ||
76ab07eb | 52 | static void setup_rock_ridge(struct iso_directory_record *de, |
ba40aaf0 | 53 | struct inode *inode, struct rock_state *rs) |
76ab07eb | 54 | { |
ba40aaf0 AM |
55 | rs->len = sizeof(struct iso_directory_record) + de->name_len[0]; |
56 | if (rs->len & 1) | |
57 | (rs->len)++; | |
58 | rs->chr = (unsigned char *)de + rs->len; | |
59 | rs->len = *((unsigned char *)de) - rs->len; | |
60 | if (rs->len < 0) | |
61 | rs->len = 0; | |
76ab07eb AM |
62 | |
63 | if (ISOFS_SB(inode->i_sb)->s_rock_offset != -1) { | |
ba40aaf0 AM |
64 | rs->len -= ISOFS_SB(inode->i_sb)->s_rock_offset; |
65 | rs->chr += ISOFS_SB(inode->i_sb)->s_rock_offset; | |
66 | if (rs->len < 0) | |
67 | rs->len = 0; | |
76ab07eb | 68 | } |
1d372116 | 69 | } |
1da177e4 | 70 | |
ba40aaf0 AM |
71 | static void init_rock_state(struct rock_state *rs, struct inode *inode) |
72 | { | |
73 | memset(rs, 0, sizeof(*rs)); | |
74 | rs->inode = inode; | |
75 | } | |
76 | ||
77 | /* | |
78 | * Returns 0 if the caller should continue scanning, 1 if the scan must end | |
79 | * and -ve on error. | |
80 | */ | |
81 | static int rock_continue(struct rock_state *rs) | |
82 | { | |
83 | int ret = 1; | |
e595447e AM |
84 | int blocksize = 1 << rs->inode->i_blkbits; |
85 | const int min_de_size = offsetof(struct rock_ridge, u); | |
ba40aaf0 AM |
86 | |
87 | kfree(rs->buffer); | |
88 | rs->buffer = NULL; | |
e595447e AM |
89 | |
90 | if ((unsigned)rs->cont_offset > blocksize - min_de_size || | |
91 | (unsigned)rs->cont_size > blocksize || | |
92 | (unsigned)(rs->cont_offset + rs->cont_size) > blocksize) { | |
93 | printk(KERN_NOTICE "rock: corrupted directory entry. " | |
94 | "extent=%d, offset=%d, size=%d\n", | |
95 | rs->cont_extent, rs->cont_offset, rs->cont_size); | |
96 | ret = -EIO; | |
97 | goto out; | |
98 | } | |
99 | ||
ba40aaf0 AM |
100 | if (rs->cont_extent) { |
101 | struct buffer_head *bh; | |
102 | ||
103 | rs->buffer = kmalloc(rs->cont_size, GFP_KERNEL); | |
104 | if (!rs->buffer) { | |
105 | ret = -ENOMEM; | |
106 | goto out; | |
107 | } | |
108 | ret = -EIO; | |
109 | bh = sb_bread(rs->inode->i_sb, rs->cont_extent); | |
110 | if (bh) { | |
111 | memcpy(rs->buffer, bh->b_data + rs->cont_offset, | |
112 | rs->cont_size); | |
113 | put_bh(bh); | |
114 | rs->chr = rs->buffer; | |
115 | rs->len = rs->cont_size; | |
116 | rs->cont_extent = 0; | |
117 | rs->cont_size = 0; | |
118 | rs->cont_offset = 0; | |
119 | return 0; | |
120 | } | |
121 | printk("Unable to read rock-ridge attributes\n"); | |
122 | } | |
123 | out: | |
124 | kfree(rs->buffer); | |
125 | rs->buffer = NULL; | |
126 | return ret; | |
127 | } | |
1da177e4 | 128 | |
7373909d AM |
129 | /* |
130 | * return length of name field; 0: not found, -1: to be ignored | |
131 | */ | |
1d372116 AM |
132 | int get_rock_ridge_filename(struct iso_directory_record *de, |
133 | char *retname, struct inode *inode) | |
1da177e4 | 134 | { |
ba40aaf0 | 135 | struct rock_state rs; |
7fa393a1 AM |
136 | struct rock_ridge *rr; |
137 | int sig; | |
138 | int retnamlen = 0; | |
139 | int truncate = 0; | |
ba40aaf0 | 140 | int ret = 0; |
1da177e4 | 141 | |
1d372116 AM |
142 | if (!ISOFS_SB(inode->i_sb)->s_rock) |
143 | return 0; | |
144 | *retname = 0; | |
145 | ||
ba40aaf0 AM |
146 | init_rock_state(&rs, inode); |
147 | setup_rock_ridge(de, inode, &rs); | |
7fa393a1 AM |
148 | repeat: |
149 | ||
ba40aaf0 AM |
150 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
151 | rr = (struct rock_ridge *)rs.chr; | |
7fa393a1 AM |
152 | if (rr->len < 3) |
153 | goto out; /* Something got screwed up here */ | |
ba40aaf0 AM |
154 | sig = isonum_721(rs.chr); |
155 | rs.chr += rr->len; | |
156 | rs.len -= rr->len; | |
157 | if (rs.len < 0) | |
7fa393a1 AM |
158 | goto out; /* corrupted isofs */ |
159 | ||
160 | switch (sig) { | |
161 | case SIG('R', 'R'): | |
162 | if ((rr->u.RR.flags[0] & RR_NM) == 0) | |
163 | goto out; | |
164 | break; | |
165 | case SIG('S', 'P'): | |
12121714 AM |
166 | if (check_sp(rr, inode)) |
167 | goto out; | |
7fa393a1 AM |
168 | break; |
169 | case SIG('C', 'E'): | |
ba40aaf0 AM |
170 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
171 | rs.cont_offset = isonum_733(rr->u.CE.offset); | |
172 | rs.cont_size = isonum_733(rr->u.CE.size); | |
7fa393a1 AM |
173 | break; |
174 | case SIG('N', 'M'): | |
175 | if (truncate) | |
1d372116 | 176 | break; |
7fa393a1 | 177 | if (rr->len < 5) |
1d372116 | 178 | break; |
7fa393a1 AM |
179 | /* |
180 | * If the flags are 2 or 4, this indicates '.' or '..'. | |
181 | * We don't want to do anything with this, because it | |
182 | * screws up the code that calls us. We don't really | |
183 | * care anyways, since we can just use the non-RR | |
184 | * name. | |
185 | */ | |
186 | if (rr->u.NM.flags & 6) | |
1d372116 | 187 | break; |
1d372116 | 188 | |
7fa393a1 AM |
189 | if (rr->u.NM.flags & ~1) { |
190 | printk("Unsupported NM flag settings (%d)\n", | |
191 | rr->u.NM.flags); | |
1d372116 | 192 | break; |
7fa393a1 AM |
193 | } |
194 | if ((strlen(retname) + rr->len - 5) >= 254) { | |
195 | truncate = 1; | |
1d372116 AM |
196 | break; |
197 | } | |
7fa393a1 AM |
198 | strncat(retname, rr->u.NM.name, rr->len - 5); |
199 | retnamlen += rr->len - 5; | |
200 | break; | |
201 | case SIG('R', 'E'): | |
ba40aaf0 | 202 | kfree(rs.buffer); |
7fa393a1 AM |
203 | return -1; |
204 | default: | |
205 | break; | |
1d372116 | 206 | } |
1da177e4 | 207 | } |
ba40aaf0 AM |
208 | ret = rock_continue(&rs); |
209 | if (ret == 0) | |
210 | goto repeat; | |
211 | if (ret == 1) | |
212 | return retnamlen; /* If 0, this file did not have a NM field */ | |
7fa393a1 | 213 | out: |
ba40aaf0 AM |
214 | kfree(rs.buffer); |
215 | return ret; | |
1da177e4 LT |
216 | } |
217 | ||
218 | static int | |
219 | parse_rock_ridge_inode_internal(struct iso_directory_record *de, | |
220 | struct inode *inode, int regard_xa) | |
221 | { | |
1d372116 | 222 | int symlink_len = 0; |
7fa393a1 AM |
223 | int cnt, sig; |
224 | struct inode *reloc; | |
225 | struct rock_ridge *rr; | |
226 | int rootflag; | |
ba40aaf0 AM |
227 | struct rock_state rs; |
228 | int ret = 0; | |
1d372116 AM |
229 | |
230 | if (!ISOFS_SB(inode->i_sb)->s_rock) | |
231 | return 0; | |
232 | ||
ba40aaf0 AM |
233 | init_rock_state(&rs, inode); |
234 | setup_rock_ridge(de, inode, &rs); | |
1d372116 | 235 | if (regard_xa) { |
ba40aaf0 AM |
236 | rs.chr += 14; |
237 | rs.len -= 14; | |
238 | if (rs.len < 0) | |
239 | rs.len = 0; | |
1d372116 AM |
240 | } |
241 | ||
7fa393a1 | 242 | repeat: |
ba40aaf0 AM |
243 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
244 | rr = (struct rock_ridge *)rs.chr; | |
7fa393a1 AM |
245 | if (rr->len < 3) |
246 | goto out; /* Something got screwed up here */ | |
ba40aaf0 AM |
247 | sig = isonum_721(rs.chr); |
248 | rs.chr += rr->len; | |
249 | rs.len -= rr->len; | |
250 | if (rs.len < 0) | |
7fa393a1 AM |
251 | goto out; /* corrupted isofs */ |
252 | ||
253 | switch (sig) { | |
1da177e4 | 254 | #ifndef CONFIG_ZISOFS /* No flag for SF or ZF */ |
7fa393a1 AM |
255 | case SIG('R', 'R'): |
256 | if ((rr->u.RR.flags[0] & | |
257 | (RR_PX | RR_TF | RR_SL | RR_CL)) == 0) | |
258 | goto out; | |
259 | break; | |
1da177e4 | 260 | #endif |
7fa393a1 | 261 | case SIG('S', 'P'): |
12121714 AM |
262 | if (check_sp(rr, inode)) |
263 | goto out; | |
7fa393a1 AM |
264 | break; |
265 | case SIG('C', 'E'): | |
ba40aaf0 AM |
266 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
267 | rs.cont_offset = isonum_733(rr->u.CE.offset); | |
268 | rs.cont_size = isonum_733(rr->u.CE.size); | |
7fa393a1 AM |
269 | break; |
270 | case SIG('E', 'R'): | |
271 | ISOFS_SB(inode->i_sb)->s_rock = 1; | |
272 | printk(KERN_DEBUG "ISO 9660 Extensions: "); | |
273 | { | |
274 | int p; | |
275 | for (p = 0; p < rr->u.ER.len_id; p++) | |
276 | printk("%c", rr->u.ER.data[p]); | |
277 | } | |
278 | printk("\n"); | |
279 | break; | |
280 | case SIG('P', 'X'): | |
281 | inode->i_mode = isonum_733(rr->u.PX.mode); | |
282 | inode->i_nlink = isonum_733(rr->u.PX.n_links); | |
283 | inode->i_uid = isonum_733(rr->u.PX.uid); | |
284 | inode->i_gid = isonum_733(rr->u.PX.gid); | |
285 | break; | |
286 | case SIG('P', 'N'): | |
287 | { | |
288 | int high, low; | |
289 | high = isonum_733(rr->u.PN.dev_high); | |
290 | low = isonum_733(rr->u.PN.dev_low); | |
291 | /* | |
292 | * The Rock Ridge standard specifies that if | |
293 | * sizeof(dev_t) <= 4, then the high field is | |
294 | * unused, and the device number is completely | |
295 | * stored in the low field. Some writers may | |
296 | * ignore this subtlety, | |
297 | * and as a result we test to see if the entire | |
298 | * device number is | |
299 | * stored in the low field, and use that. | |
300 | */ | |
301 | if ((low & ~0xff) && high == 0) { | |
302 | inode->i_rdev = | |
303 | MKDEV(low >> 8, low & 0xff); | |
304 | } else { | |
305 | inode->i_rdev = | |
306 | MKDEV(high, low); | |
1d372116 | 307 | } |
7fa393a1 AM |
308 | } |
309 | break; | |
310 | case SIG('T', 'F'): | |
311 | /* | |
312 | * Some RRIP writers incorrectly place ctime in the | |
313 | * TF_CREATE field. Try to handle this correctly for | |
314 | * either case. | |
315 | */ | |
316 | /* Rock ridge never appears on a High Sierra disk */ | |
317 | cnt = 0; | |
318 | if (rr->u.TF.flags & TF_CREATE) { | |
319 | inode->i_ctime.tv_sec = | |
320 | iso_date(rr->u.TF.times[cnt++].time, | |
321 | 0); | |
322 | inode->i_ctime.tv_nsec = 0; | |
323 | } | |
324 | if (rr->u.TF.flags & TF_MODIFY) { | |
325 | inode->i_mtime.tv_sec = | |
326 | iso_date(rr->u.TF.times[cnt++].time, | |
327 | 0); | |
328 | inode->i_mtime.tv_nsec = 0; | |
329 | } | |
330 | if (rr->u.TF.flags & TF_ACCESS) { | |
331 | inode->i_atime.tv_sec = | |
332 | iso_date(rr->u.TF.times[cnt++].time, | |
333 | 0); | |
334 | inode->i_atime.tv_nsec = 0; | |
335 | } | |
336 | if (rr->u.TF.flags & TF_ATTRIBUTES) { | |
337 | inode->i_ctime.tv_sec = | |
338 | iso_date(rr->u.TF.times[cnt++].time, | |
339 | 0); | |
340 | inode->i_ctime.tv_nsec = 0; | |
341 | } | |
342 | break; | |
343 | case SIG('S', 'L'): | |
344 | { | |
345 | int slen; | |
346 | struct SL_component *slp; | |
347 | struct SL_component *oldslp; | |
348 | slen = rr->len - 5; | |
349 | slp = &rr->u.SL.link; | |
350 | inode->i_size = symlink_len; | |
351 | while (slen > 1) { | |
352 | rootflag = 0; | |
353 | switch (slp->flags & ~1) { | |
354 | case 0: | |
355 | inode->i_size += | |
356 | slp->len; | |
357 | break; | |
358 | case 2: | |
359 | inode->i_size += 1; | |
360 | break; | |
361 | case 4: | |
362 | inode->i_size += 2; | |
363 | break; | |
364 | case 8: | |
365 | rootflag = 1; | |
366 | inode->i_size += 1; | |
367 | break; | |
368 | default: | |
369 | printk("Symlink component flag " | |
370 | "not implemented\n"); | |
1d372116 | 371 | } |
7fa393a1 AM |
372 | slen -= slp->len + 2; |
373 | oldslp = slp; | |
374 | slp = (struct SL_component *) | |
375 | (((char *)slp) + slp->len + 2); | |
376 | ||
377 | if (slen < 2) { | |
378 | if (((rr->u.SL. | |
379 | flags & 1) != 0) | |
380 | && | |
381 | ((oldslp-> | |
382 | flags & 1) == 0)) | |
1d372116 | 383 | inode->i_size += |
7fa393a1 AM |
384 | 1; |
385 | break; | |
1d372116 | 386 | } |
7fa393a1 AM |
387 | |
388 | /* | |
389 | * If this component record isn't | |
390 | * continued, then append a '/'. | |
391 | */ | |
392 | if (!rootflag | |
393 | && (oldslp->flags & 1) == 0) | |
394 | inode->i_size += 1; | |
1d372116 | 395 | } |
7fa393a1 AM |
396 | } |
397 | symlink_len = inode->i_size; | |
398 | break; | |
399 | case SIG('R', 'E'): | |
400 | printk(KERN_WARNING "Attempt to read inode for " | |
401 | "relocated directory\n"); | |
402 | goto out; | |
403 | case SIG('C', 'L'): | |
404 | ISOFS_I(inode)->i_first_extent = | |
405 | isonum_733(rr->u.CL.location); | |
406 | reloc = | |
407 | isofs_iget(inode->i_sb, | |
408 | ISOFS_I(inode)->i_first_extent, | |
409 | 0); | |
410 | if (!reloc) | |
1d372116 | 411 | goto out; |
7fa393a1 AM |
412 | inode->i_mode = reloc->i_mode; |
413 | inode->i_nlink = reloc->i_nlink; | |
414 | inode->i_uid = reloc->i_uid; | |
415 | inode->i_gid = reloc->i_gid; | |
416 | inode->i_rdev = reloc->i_rdev; | |
417 | inode->i_size = reloc->i_size; | |
418 | inode->i_blocks = reloc->i_blocks; | |
419 | inode->i_atime = reloc->i_atime; | |
420 | inode->i_ctime = reloc->i_ctime; | |
421 | inode->i_mtime = reloc->i_mtime; | |
422 | iput(reloc); | |
423 | break; | |
1da177e4 | 424 | #ifdef CONFIG_ZISOFS |
7fa393a1 AM |
425 | case SIG('Z', 'F'): { |
426 | int algo; | |
427 | ||
428 | if (ISOFS_SB(inode->i_sb)->s_nocompress) | |
1d372116 | 429 | break; |
7fa393a1 AM |
430 | algo = isonum_721(rr->u.ZF.algorithm); |
431 | if (algo == SIG('p', 'z')) { | |
432 | int block_shift = | |
433 | isonum_711(&rr->u.ZF.parms[1]); | |
434 | if (block_shift < PAGE_CACHE_SHIFT | |
435 | || block_shift > 17) { | |
436 | printk(KERN_WARNING "isofs: " | |
437 | "Can't handle ZF block " | |
438 | "size of 2^%d\n", | |
439 | block_shift); | |
440 | } else { | |
441 | /* | |
442 | * Note: we don't change | |
443 | * i_blocks here | |
444 | */ | |
445 | ISOFS_I(inode)->i_file_format = | |
446 | isofs_file_compressed; | |
447 | /* | |
448 | * Parameters to compression | |
449 | * algorithm (header size, | |
450 | * block size) | |
451 | */ | |
452 | ISOFS_I(inode)->i_format_parm[0] = | |
453 | isonum_711(&rr->u.ZF.parms[0]); | |
454 | ISOFS_I(inode)->i_format_parm[1] = | |
455 | isonum_711(&rr->u.ZF.parms[1]); | |
456 | inode->i_size = | |
457 | isonum_733(rr->u.ZF. | |
458 | real_size); | |
459 | } | |
460 | } else { | |
461 | printk(KERN_WARNING | |
462 | "isofs: Unknown ZF compression " | |
463 | "algorithm: %c%c\n", | |
464 | rr->u.ZF.algorithm[0], | |
465 | rr->u.ZF.algorithm[1]); | |
1d372116 | 466 | } |
7fa393a1 AM |
467 | break; |
468 | } | |
469 | #endif | |
470 | default: | |
471 | break; | |
1d372116 AM |
472 | } |
473 | } | |
ba40aaf0 AM |
474 | ret = rock_continue(&rs); |
475 | if (ret == 0) | |
476 | goto repeat; | |
477 | if (ret == 1) | |
478 | ret = 0; | |
7fa393a1 | 479 | out: |
ba40aaf0 AM |
480 | kfree(rs.buffer); |
481 | return ret; | |
1da177e4 LT |
482 | } |
483 | ||
484 | static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit) | |
485 | { | |
486 | int slen; | |
487 | int rootflag; | |
488 | struct SL_component *oldslp; | |
489 | struct SL_component *slp; | |
490 | slen = rr->len - 5; | |
491 | slp = &rr->u.SL.link; | |
492 | while (slen > 1) { | |
493 | rootflag = 0; | |
494 | switch (slp->flags & ~1) { | |
495 | case 0: | |
496 | if (slp->len > plimit - rpnt) | |
497 | return NULL; | |
498 | memcpy(rpnt, slp->text, slp->len); | |
1d372116 | 499 | rpnt += slp->len; |
1da177e4 LT |
500 | break; |
501 | case 2: | |
502 | if (rpnt >= plimit) | |
503 | return NULL; | |
1d372116 | 504 | *rpnt++ = '.'; |
1da177e4 LT |
505 | break; |
506 | case 4: | |
507 | if (2 > plimit - rpnt) | |
508 | return NULL; | |
1d372116 AM |
509 | *rpnt++ = '.'; |
510 | *rpnt++ = '.'; | |
1da177e4 LT |
511 | break; |
512 | case 8: | |
513 | if (rpnt >= plimit) | |
514 | return NULL; | |
515 | rootflag = 1; | |
1d372116 | 516 | *rpnt++ = '/'; |
1da177e4 LT |
517 | break; |
518 | default: | |
519 | printk("Symlink component flag not implemented (%d)\n", | |
1d372116 | 520 | slp->flags); |
1da177e4 LT |
521 | } |
522 | slen -= slp->len + 2; | |
523 | oldslp = slp; | |
1d372116 | 524 | slp = (struct SL_component *)((char *)slp + slp->len + 2); |
1da177e4 LT |
525 | |
526 | if (slen < 2) { | |
527 | /* | |
528 | * If there is another SL record, and this component | |
529 | * record isn't continued, then add a slash. | |
530 | */ | |
531 | if ((!rootflag) && (rr->u.SL.flags & 1) && | |
532 | !(oldslp->flags & 1)) { | |
533 | if (rpnt >= plimit) | |
534 | return NULL; | |
1d372116 | 535 | *rpnt++ = '/'; |
1da177e4 LT |
536 | } |
537 | break; | |
538 | } | |
539 | ||
540 | /* | |
541 | * If this component record isn't continued, then append a '/'. | |
542 | */ | |
543 | if (!rootflag && !(oldslp->flags & 1)) { | |
544 | if (rpnt >= plimit) | |
545 | return NULL; | |
1d372116 | 546 | *rpnt++ = '/'; |
1da177e4 LT |
547 | } |
548 | } | |
549 | return rpnt; | |
550 | } | |
551 | ||
1d372116 | 552 | int parse_rock_ridge_inode(struct iso_directory_record *de, struct inode *inode) |
1da177e4 | 553 | { |
1d372116 | 554 | int result = parse_rock_ridge_inode_internal(de, inode, 0); |
7373909d AM |
555 | |
556 | /* | |
557 | * if rockridge flag was reset and we didn't look for attributes | |
558 | * behind eventual XA attributes, have a look there | |
559 | */ | |
1d372116 AM |
560 | if ((ISOFS_SB(inode->i_sb)->s_rock_offset == -1) |
561 | && (ISOFS_SB(inode->i_sb)->s_rock == 2)) { | |
562 | result = parse_rock_ridge_inode_internal(de, inode, 14); | |
563 | } | |
564 | return result; | |
1da177e4 LT |
565 | } |
566 | ||
7373909d AM |
567 | /* |
568 | * readpage() for symlinks: reads symlink contents into the page and either | |
569 | * makes it uptodate and returns 0 or returns error (-EIO) | |
570 | */ | |
1da177e4 LT |
571 | static int rock_ridge_symlink_readpage(struct file *file, struct page *page) |
572 | { | |
573 | struct inode *inode = page->mapping->host; | |
1d372116 | 574 | struct iso_inode_info *ei = ISOFS_I(inode); |
1da177e4 LT |
575 | char *link = kmap(page); |
576 | unsigned long bufsize = ISOFS_BUFFER_SIZE(inode); | |
577 | struct buffer_head *bh; | |
578 | char *rpnt = link; | |
579 | unsigned char *pnt; | |
76ab07eb | 580 | struct iso_directory_record *raw_de; |
1da177e4 LT |
581 | unsigned long block, offset; |
582 | int sig; | |
1da177e4 | 583 | struct rock_ridge *rr; |
ba40aaf0 AM |
584 | struct rock_state rs; |
585 | int ret; | |
1da177e4 LT |
586 | |
587 | if (!ISOFS_SB(inode->i_sb)->s_rock) | |
588 | goto error; | |
589 | ||
ba40aaf0 | 590 | init_rock_state(&rs, inode); |
1da177e4 LT |
591 | block = ei->i_iget5_block; |
592 | lock_kernel(); | |
593 | bh = sb_bread(inode->i_sb, block); | |
594 | if (!bh) | |
595 | goto out_noread; | |
596 | ||
1d372116 AM |
597 | offset = ei->i_iget5_offset; |
598 | pnt = (unsigned char *)bh->b_data + offset; | |
1da177e4 | 599 | |
76ab07eb | 600 | raw_de = (struct iso_directory_record *)pnt; |
1da177e4 LT |
601 | |
602 | /* | |
603 | * If we go past the end of the buffer, there is some sort of error. | |
604 | */ | |
605 | if (offset + *pnt > bufsize) | |
606 | goto out_bad_span; | |
607 | ||
7373909d AM |
608 | /* |
609 | * Now test for possible Rock Ridge extensions which will override | |
610 | * some of these numbers in the inode structure. | |
611 | */ | |
1da177e4 | 612 | |
ba40aaf0 | 613 | setup_rock_ridge(raw_de, inode, &rs); |
1da177e4 | 614 | |
7fa393a1 | 615 | repeat: |
ba40aaf0 AM |
616 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
617 | rr = (struct rock_ridge *)rs.chr; | |
1da177e4 LT |
618 | if (rr->len < 3) |
619 | goto out; /* Something got screwed up here */ | |
ba40aaf0 AM |
620 | sig = isonum_721(rs.chr); |
621 | rs.chr += rr->len; | |
622 | rs.len -= rr->len; | |
623 | if (rs.len < 0) | |
1da177e4 LT |
624 | goto out; /* corrupted isofs */ |
625 | ||
626 | switch (sig) { | |
627 | case SIG('R', 'R'): | |
628 | if ((rr->u.RR.flags[0] & RR_SL) == 0) | |
629 | goto out; | |
630 | break; | |
631 | case SIG('S', 'P'): | |
12121714 AM |
632 | if (check_sp(rr, inode)) |
633 | goto out; | |
1da177e4 LT |
634 | break; |
635 | case SIG('S', 'L'): | |
636 | rpnt = get_symlink_chunk(rpnt, rr, | |
637 | link + (PAGE_SIZE - 1)); | |
638 | if (rpnt == NULL) | |
639 | goto out; | |
640 | break; | |
641 | case SIG('C', 'E'): | |
642 | /* This tells is if there is a continuation record */ | |
ba40aaf0 AM |
643 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
644 | rs.cont_offset = isonum_733(rr->u.CE.offset); | |
645 | rs.cont_size = isonum_733(rr->u.CE.size); | |
1da177e4 LT |
646 | default: |
647 | break; | |
648 | } | |
649 | } | |
ba40aaf0 AM |
650 | ret = rock_continue(&rs); |
651 | if (ret == 0) | |
652 | goto repeat; | |
653 | if (ret < 0) | |
654 | goto fail; | |
1da177e4 LT |
655 | |
656 | if (rpnt == link) | |
657 | goto fail; | |
658 | brelse(bh); | |
659 | *rpnt = '\0'; | |
660 | unlock_kernel(); | |
661 | SetPageUptodate(page); | |
662 | kunmap(page); | |
663 | unlock_page(page); | |
664 | return 0; | |
665 | ||
666 | /* error exit from macro */ | |
7fa393a1 | 667 | out: |
ba40aaf0 | 668 | kfree(rs.buffer); |
1da177e4 | 669 | goto fail; |
7fa393a1 | 670 | out_noread: |
1da177e4 LT |
671 | printk("unable to read i-node block"); |
672 | goto fail; | |
7fa393a1 | 673 | out_bad_span: |
1da177e4 | 674 | printk("symlink spans iso9660 blocks\n"); |
7fa393a1 | 675 | fail: |
1da177e4 LT |
676 | brelse(bh); |
677 | unlock_kernel(); | |
7fa393a1 | 678 | error: |
1da177e4 LT |
679 | SetPageError(page); |
680 | kunmap(page); | |
681 | unlock_page(page); | |
682 | return -EIO; | |
683 | } | |
684 | ||
685 | struct address_space_operations isofs_symlink_aops = { | |
1d372116 | 686 | .readpage = rock_ridge_symlink_readpage |
1da177e4 | 687 | }; |