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> | |
1da177e4 | 11 | |
94f2f715 | 12 | #include "isofs.h" |
1da177e4 LT |
13 | #include "rock.h" |
14 | ||
7373909d AM |
15 | /* |
16 | * These functions are designed to read the system areas of a directory record | |
1da177e4 LT |
17 | * and extract relevant information. There are different functions provided |
18 | * depending upon what information we need at the time. One function fills | |
19 | * out an inode structure, a second one extracts a filename, a third one | |
20 | * returns a symbolic link name, and a fourth one returns the extent number | |
7373909d AM |
21 | * for the file. |
22 | */ | |
1da177e4 | 23 | |
1d372116 | 24 | #define SIG(A,B) ((A) | ((B) << 8)) /* isonum_721() */ |
1da177e4 | 25 | |
ba40aaf0 AM |
26 | struct rock_state { |
27 | void *buffer; | |
28 | unsigned char *chr; | |
29 | int len; | |
30 | int cont_size; | |
31 | int cont_extent; | |
32 | int cont_offset; | |
33 | struct inode *inode; | |
34 | }; | |
35 | ||
12121714 AM |
36 | /* |
37 | * This is a way of ensuring that we have something in the system | |
7373909d | 38 | * use fields that is compatible with Rock Ridge. Return zero on success. |
12121714 AM |
39 | */ |
40 | ||
41 | static int check_sp(struct rock_ridge *rr, struct inode *inode) | |
42 | { | |
43 | if (rr->u.SP.magic[0] != 0xbe) | |
44 | return -1; | |
45 | if (rr->u.SP.magic[1] != 0xef) | |
46 | return -1; | |
47 | ISOFS_SB(inode->i_sb)->s_rock_offset = rr->u.SP.skip; | |
48 | return 0; | |
49 | } | |
50 | ||
76ab07eb | 51 | static void setup_rock_ridge(struct iso_directory_record *de, |
ba40aaf0 | 52 | struct inode *inode, struct rock_state *rs) |
76ab07eb | 53 | { |
ba40aaf0 AM |
54 | rs->len = sizeof(struct iso_directory_record) + de->name_len[0]; |
55 | if (rs->len & 1) | |
56 | (rs->len)++; | |
57 | rs->chr = (unsigned char *)de + rs->len; | |
58 | rs->len = *((unsigned char *)de) - rs->len; | |
59 | if (rs->len < 0) | |
60 | rs->len = 0; | |
76ab07eb AM |
61 | |
62 | if (ISOFS_SB(inode->i_sb)->s_rock_offset != -1) { | |
ba40aaf0 AM |
63 | rs->len -= ISOFS_SB(inode->i_sb)->s_rock_offset; |
64 | rs->chr += ISOFS_SB(inode->i_sb)->s_rock_offset; | |
65 | if (rs->len < 0) | |
66 | rs->len = 0; | |
76ab07eb | 67 | } |
1d372116 | 68 | } |
1da177e4 | 69 | |
ba40aaf0 AM |
70 | static void init_rock_state(struct rock_state *rs, struct inode *inode) |
71 | { | |
72 | memset(rs, 0, sizeof(*rs)); | |
73 | rs->inode = inode; | |
74 | } | |
75 | ||
76 | /* | |
77 | * Returns 0 if the caller should continue scanning, 1 if the scan must end | |
78 | * and -ve on error. | |
79 | */ | |
80 | static int rock_continue(struct rock_state *rs) | |
81 | { | |
82 | int ret = 1; | |
e595447e AM |
83 | int blocksize = 1 << rs->inode->i_blkbits; |
84 | const int min_de_size = offsetof(struct rock_ridge, u); | |
ba40aaf0 AM |
85 | |
86 | kfree(rs->buffer); | |
87 | rs->buffer = NULL; | |
e595447e AM |
88 | |
89 | if ((unsigned)rs->cont_offset > blocksize - min_de_size || | |
90 | (unsigned)rs->cont_size > blocksize || | |
91 | (unsigned)(rs->cont_offset + rs->cont_size) > blocksize) { | |
92 | printk(KERN_NOTICE "rock: corrupted directory entry. " | |
93 | "extent=%d, offset=%d, size=%d\n", | |
94 | rs->cont_extent, rs->cont_offset, rs->cont_size); | |
95 | ret = -EIO; | |
96 | goto out; | |
97 | } | |
98 | ||
ba40aaf0 AM |
99 | if (rs->cont_extent) { |
100 | struct buffer_head *bh; | |
101 | ||
102 | rs->buffer = kmalloc(rs->cont_size, GFP_KERNEL); | |
103 | if (!rs->buffer) { | |
104 | ret = -ENOMEM; | |
105 | goto out; | |
106 | } | |
107 | ret = -EIO; | |
108 | bh = sb_bread(rs->inode->i_sb, rs->cont_extent); | |
109 | if (bh) { | |
110 | memcpy(rs->buffer, bh->b_data + rs->cont_offset, | |
111 | rs->cont_size); | |
112 | put_bh(bh); | |
113 | rs->chr = rs->buffer; | |
114 | rs->len = rs->cont_size; | |
115 | rs->cont_extent = 0; | |
116 | rs->cont_size = 0; | |
117 | rs->cont_offset = 0; | |
118 | return 0; | |
119 | } | |
120 | printk("Unable to read rock-ridge attributes\n"); | |
121 | } | |
122 | out: | |
123 | kfree(rs->buffer); | |
124 | rs->buffer = NULL; | |
125 | return ret; | |
126 | } | |
1da177e4 | 127 | |
f2966632 AM |
128 | /* |
129 | * We think there's a record of type `sig' at rs->chr. Parse the signature | |
130 | * and make sure that there's really room for a record of that type. | |
131 | */ | |
132 | static int rock_check_overflow(struct rock_state *rs, int sig) | |
133 | { | |
134 | int len; | |
135 | ||
136 | switch (sig) { | |
137 | case SIG('S', 'P'): | |
138 | len = sizeof(struct SU_SP_s); | |
139 | break; | |
140 | case SIG('C', 'E'): | |
141 | len = sizeof(struct SU_CE_s); | |
142 | break; | |
143 | case SIG('E', 'R'): | |
144 | len = sizeof(struct SU_ER_s); | |
145 | break; | |
146 | case SIG('R', 'R'): | |
147 | len = sizeof(struct RR_RR_s); | |
148 | break; | |
149 | case SIG('P', 'X'): | |
150 | len = sizeof(struct RR_PX_s); | |
151 | break; | |
152 | case SIG('P', 'N'): | |
153 | len = sizeof(struct RR_PN_s); | |
154 | break; | |
155 | case SIG('S', 'L'): | |
156 | len = sizeof(struct RR_SL_s); | |
157 | break; | |
158 | case SIG('N', 'M'): | |
159 | len = sizeof(struct RR_NM_s); | |
160 | break; | |
161 | case SIG('C', 'L'): | |
162 | len = sizeof(struct RR_CL_s); | |
163 | break; | |
164 | case SIG('P', 'L'): | |
165 | len = sizeof(struct RR_PL_s); | |
166 | break; | |
167 | case SIG('T', 'F'): | |
168 | len = sizeof(struct RR_TF_s); | |
169 | break; | |
170 | case SIG('Z', 'F'): | |
171 | len = sizeof(struct RR_ZF_s); | |
172 | break; | |
173 | default: | |
174 | len = 0; | |
175 | break; | |
176 | } | |
177 | len += offsetof(struct rock_ridge, u); | |
178 | if (len > rs->len) { | |
179 | printk(KERN_NOTICE "rock: directory entry would overflow " | |
180 | "storage\n"); | |
181 | printk(KERN_NOTICE "rock: sig=0x%02x, size=%d, remaining=%d\n", | |
182 | sig, len, rs->len); | |
183 | return -EIO; | |
184 | } | |
185 | return 0; | |
186 | } | |
187 | ||
7373909d AM |
188 | /* |
189 | * return length of name field; 0: not found, -1: to be ignored | |
190 | */ | |
1d372116 AM |
191 | int get_rock_ridge_filename(struct iso_directory_record *de, |
192 | char *retname, struct inode *inode) | |
1da177e4 | 193 | { |
ba40aaf0 | 194 | struct rock_state rs; |
7fa393a1 AM |
195 | struct rock_ridge *rr; |
196 | int sig; | |
197 | int retnamlen = 0; | |
198 | int truncate = 0; | |
ba40aaf0 | 199 | int ret = 0; |
1da177e4 | 200 | |
1d372116 AM |
201 | if (!ISOFS_SB(inode->i_sb)->s_rock) |
202 | return 0; | |
203 | *retname = 0; | |
204 | ||
ba40aaf0 AM |
205 | init_rock_state(&rs, inode); |
206 | setup_rock_ridge(de, inode, &rs); | |
7fa393a1 AM |
207 | repeat: |
208 | ||
ba40aaf0 AM |
209 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
210 | rr = (struct rock_ridge *)rs.chr; | |
c0a1633b AG |
211 | /* |
212 | * Ignore rock ridge info if rr->len is out of range, but | |
213 | * don't return -EIO because that would make the file | |
214 | * invisible. | |
215 | */ | |
7fa393a1 AM |
216 | if (rr->len < 3) |
217 | goto out; /* Something got screwed up here */ | |
ba40aaf0 | 218 | sig = isonum_721(rs.chr); |
f2966632 AM |
219 | if (rock_check_overflow(&rs, sig)) |
220 | goto eio; | |
ba40aaf0 AM |
221 | rs.chr += rr->len; |
222 | rs.len -= rr->len; | |
c0a1633b AG |
223 | /* |
224 | * As above, just ignore the rock ridge info if rr->len | |
225 | * is bogus. | |
226 | */ | |
ba40aaf0 | 227 | if (rs.len < 0) |
c0a1633b | 228 | goto out; /* Something got screwed up here */ |
7fa393a1 AM |
229 | |
230 | switch (sig) { | |
231 | case SIG('R', 'R'): | |
232 | if ((rr->u.RR.flags[0] & RR_NM) == 0) | |
233 | goto out; | |
234 | break; | |
235 | case SIG('S', 'P'): | |
12121714 AM |
236 | if (check_sp(rr, inode)) |
237 | goto out; | |
7fa393a1 AM |
238 | break; |
239 | case SIG('C', 'E'): | |
ba40aaf0 AM |
240 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
241 | rs.cont_offset = isonum_733(rr->u.CE.offset); | |
242 | rs.cont_size = isonum_733(rr->u.CE.size); | |
7fa393a1 AM |
243 | break; |
244 | case SIG('N', 'M'): | |
245 | if (truncate) | |
1d372116 | 246 | break; |
7fa393a1 | 247 | if (rr->len < 5) |
1d372116 | 248 | break; |
7fa393a1 AM |
249 | /* |
250 | * If the flags are 2 or 4, this indicates '.' or '..'. | |
251 | * We don't want to do anything with this, because it | |
252 | * screws up the code that calls us. We don't really | |
253 | * care anyways, since we can just use the non-RR | |
254 | * name. | |
255 | */ | |
256 | if (rr->u.NM.flags & 6) | |
1d372116 | 257 | break; |
1d372116 | 258 | |
7fa393a1 AM |
259 | if (rr->u.NM.flags & ~1) { |
260 | printk("Unsupported NM flag settings (%d)\n", | |
261 | rr->u.NM.flags); | |
1d372116 | 262 | break; |
7fa393a1 AM |
263 | } |
264 | if ((strlen(retname) + rr->len - 5) >= 254) { | |
265 | truncate = 1; | |
1d372116 AM |
266 | break; |
267 | } | |
7fa393a1 AM |
268 | strncat(retname, rr->u.NM.name, rr->len - 5); |
269 | retnamlen += rr->len - 5; | |
270 | break; | |
271 | case SIG('R', 'E'): | |
ba40aaf0 | 272 | kfree(rs.buffer); |
7fa393a1 AM |
273 | return -1; |
274 | default: | |
275 | break; | |
1d372116 | 276 | } |
1da177e4 | 277 | } |
ba40aaf0 AM |
278 | ret = rock_continue(&rs); |
279 | if (ret == 0) | |
280 | goto repeat; | |
281 | if (ret == 1) | |
282 | return retnamlen; /* If 0, this file did not have a NM field */ | |
7fa393a1 | 283 | out: |
ba40aaf0 AM |
284 | kfree(rs.buffer); |
285 | return ret; | |
f2966632 AM |
286 | eio: |
287 | ret = -EIO; | |
288 | goto out; | |
1da177e4 LT |
289 | } |
290 | ||
291 | static int | |
292 | parse_rock_ridge_inode_internal(struct iso_directory_record *de, | |
293 | struct inode *inode, int regard_xa) | |
294 | { | |
1d372116 | 295 | int symlink_len = 0; |
7fa393a1 AM |
296 | int cnt, sig; |
297 | struct inode *reloc; | |
298 | struct rock_ridge *rr; | |
299 | int rootflag; | |
ba40aaf0 AM |
300 | struct rock_state rs; |
301 | int ret = 0; | |
1d372116 AM |
302 | |
303 | if (!ISOFS_SB(inode->i_sb)->s_rock) | |
304 | return 0; | |
305 | ||
ba40aaf0 AM |
306 | init_rock_state(&rs, inode); |
307 | setup_rock_ridge(de, inode, &rs); | |
1d372116 | 308 | if (regard_xa) { |
ba40aaf0 AM |
309 | rs.chr += 14; |
310 | rs.len -= 14; | |
311 | if (rs.len < 0) | |
312 | rs.len = 0; | |
1d372116 AM |
313 | } |
314 | ||
7fa393a1 | 315 | repeat: |
ba40aaf0 AM |
316 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
317 | rr = (struct rock_ridge *)rs.chr; | |
c0a1633b AG |
318 | /* |
319 | * Ignore rock ridge info if rr->len is out of range, but | |
320 | * don't return -EIO because that would make the file | |
321 | * invisible. | |
322 | */ | |
7fa393a1 AM |
323 | if (rr->len < 3) |
324 | goto out; /* Something got screwed up here */ | |
ba40aaf0 | 325 | sig = isonum_721(rs.chr); |
f2966632 AM |
326 | if (rock_check_overflow(&rs, sig)) |
327 | goto eio; | |
ba40aaf0 AM |
328 | rs.chr += rr->len; |
329 | rs.len -= rr->len; | |
c0a1633b AG |
330 | /* |
331 | * As above, just ignore the rock ridge info if rr->len | |
332 | * is bogus. | |
333 | */ | |
ba40aaf0 | 334 | if (rs.len < 0) |
c0a1633b | 335 | goto out; /* Something got screwed up here */ |
7fa393a1 AM |
336 | |
337 | switch (sig) { | |
1da177e4 | 338 | #ifndef CONFIG_ZISOFS /* No flag for SF or ZF */ |
7fa393a1 AM |
339 | case SIG('R', 'R'): |
340 | if ((rr->u.RR.flags[0] & | |
341 | (RR_PX | RR_TF | RR_SL | RR_CL)) == 0) | |
342 | goto out; | |
343 | break; | |
1da177e4 | 344 | #endif |
7fa393a1 | 345 | case SIG('S', 'P'): |
12121714 AM |
346 | if (check_sp(rr, inode)) |
347 | goto out; | |
7fa393a1 AM |
348 | break; |
349 | case SIG('C', 'E'): | |
ba40aaf0 AM |
350 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
351 | rs.cont_offset = isonum_733(rr->u.CE.offset); | |
352 | rs.cont_size = isonum_733(rr->u.CE.size); | |
7fa393a1 AM |
353 | break; |
354 | case SIG('E', 'R'): | |
355 | ISOFS_SB(inode->i_sb)->s_rock = 1; | |
356 | printk(KERN_DEBUG "ISO 9660 Extensions: "); | |
357 | { | |
358 | int p; | |
359 | for (p = 0; p < rr->u.ER.len_id; p++) | |
360 | printk("%c", rr->u.ER.data[p]); | |
361 | } | |
362 | printk("\n"); | |
363 | break; | |
364 | case SIG('P', 'X'): | |
365 | inode->i_mode = isonum_733(rr->u.PX.mode); | |
bfe86848 | 366 | set_nlink(inode, isonum_733(rr->u.PX.n_links)); |
7fa393a1 AM |
367 | inode->i_uid = isonum_733(rr->u.PX.uid); |
368 | inode->i_gid = isonum_733(rr->u.PX.gid); | |
369 | break; | |
370 | case SIG('P', 'N'): | |
371 | { | |
372 | int high, low; | |
373 | high = isonum_733(rr->u.PN.dev_high); | |
374 | low = isonum_733(rr->u.PN.dev_low); | |
375 | /* | |
376 | * The Rock Ridge standard specifies that if | |
377 | * sizeof(dev_t) <= 4, then the high field is | |
378 | * unused, and the device number is completely | |
379 | * stored in the low field. Some writers may | |
380 | * ignore this subtlety, | |
381 | * and as a result we test to see if the entire | |
382 | * device number is | |
383 | * stored in the low field, and use that. | |
384 | */ | |
385 | if ((low & ~0xff) && high == 0) { | |
386 | inode->i_rdev = | |
387 | MKDEV(low >> 8, low & 0xff); | |
388 | } else { | |
389 | inode->i_rdev = | |
390 | MKDEV(high, low); | |
1d372116 | 391 | } |
7fa393a1 AM |
392 | } |
393 | break; | |
394 | case SIG('T', 'F'): | |
395 | /* | |
396 | * Some RRIP writers incorrectly place ctime in the | |
397 | * TF_CREATE field. Try to handle this correctly for | |
398 | * either case. | |
399 | */ | |
400 | /* Rock ridge never appears on a High Sierra disk */ | |
401 | cnt = 0; | |
402 | if (rr->u.TF.flags & TF_CREATE) { | |
403 | inode->i_ctime.tv_sec = | |
404 | iso_date(rr->u.TF.times[cnt++].time, | |
405 | 0); | |
406 | inode->i_ctime.tv_nsec = 0; | |
407 | } | |
408 | if (rr->u.TF.flags & TF_MODIFY) { | |
409 | inode->i_mtime.tv_sec = | |
410 | iso_date(rr->u.TF.times[cnt++].time, | |
411 | 0); | |
412 | inode->i_mtime.tv_nsec = 0; | |
413 | } | |
414 | if (rr->u.TF.flags & TF_ACCESS) { | |
415 | inode->i_atime.tv_sec = | |
416 | iso_date(rr->u.TF.times[cnt++].time, | |
417 | 0); | |
418 | inode->i_atime.tv_nsec = 0; | |
419 | } | |
420 | if (rr->u.TF.flags & TF_ATTRIBUTES) { | |
421 | inode->i_ctime.tv_sec = | |
422 | iso_date(rr->u.TF.times[cnt++].time, | |
423 | 0); | |
424 | inode->i_ctime.tv_nsec = 0; | |
425 | } | |
426 | break; | |
427 | case SIG('S', 'L'): | |
428 | { | |
429 | int slen; | |
430 | struct SL_component *slp; | |
431 | struct SL_component *oldslp; | |
432 | slen = rr->len - 5; | |
433 | slp = &rr->u.SL.link; | |
434 | inode->i_size = symlink_len; | |
435 | while (slen > 1) { | |
436 | rootflag = 0; | |
437 | switch (slp->flags & ~1) { | |
438 | case 0: | |
439 | inode->i_size += | |
440 | slp->len; | |
441 | break; | |
442 | case 2: | |
443 | inode->i_size += 1; | |
444 | break; | |
445 | case 4: | |
446 | inode->i_size += 2; | |
447 | break; | |
448 | case 8: | |
449 | rootflag = 1; | |
450 | inode->i_size += 1; | |
451 | break; | |
452 | default: | |
453 | printk("Symlink component flag " | |
454 | "not implemented\n"); | |
1d372116 | 455 | } |
7fa393a1 AM |
456 | slen -= slp->len + 2; |
457 | oldslp = slp; | |
458 | slp = (struct SL_component *) | |
459 | (((char *)slp) + slp->len + 2); | |
460 | ||
461 | if (slen < 2) { | |
462 | if (((rr->u.SL. | |
463 | flags & 1) != 0) | |
464 | && | |
465 | ((oldslp-> | |
466 | flags & 1) == 0)) | |
1d372116 | 467 | inode->i_size += |
7fa393a1 AM |
468 | 1; |
469 | break; | |
1d372116 | 470 | } |
7fa393a1 AM |
471 | |
472 | /* | |
473 | * If this component record isn't | |
474 | * continued, then append a '/'. | |
475 | */ | |
476 | if (!rootflag | |
477 | && (oldslp->flags & 1) == 0) | |
478 | inode->i_size += 1; | |
1d372116 | 479 | } |
7fa393a1 AM |
480 | } |
481 | symlink_len = inode->i_size; | |
482 | break; | |
483 | case SIG('R', 'E'): | |
484 | printk(KERN_WARNING "Attempt to read inode for " | |
485 | "relocated directory\n"); | |
486 | goto out; | |
487 | case SIG('C', 'L'): | |
488 | ISOFS_I(inode)->i_first_extent = | |
489 | isonum_733(rr->u.CL.location); | |
490 | reloc = | |
491 | isofs_iget(inode->i_sb, | |
492 | ISOFS_I(inode)->i_first_extent, | |
493 | 0); | |
c4386c83 DH |
494 | if (IS_ERR(reloc)) { |
495 | ret = PTR_ERR(reloc); | |
1d372116 | 496 | goto out; |
c4386c83 | 497 | } |
7fa393a1 | 498 | inode->i_mode = reloc->i_mode; |
bfe86848 | 499 | set_nlink(inode, reloc->i_nlink); |
7fa393a1 AM |
500 | inode->i_uid = reloc->i_uid; |
501 | inode->i_gid = reloc->i_gid; | |
502 | inode->i_rdev = reloc->i_rdev; | |
503 | inode->i_size = reloc->i_size; | |
504 | inode->i_blocks = reloc->i_blocks; | |
505 | inode->i_atime = reloc->i_atime; | |
506 | inode->i_ctime = reloc->i_ctime; | |
507 | inode->i_mtime = reloc->i_mtime; | |
508 | iput(reloc); | |
509 | break; | |
1da177e4 | 510 | #ifdef CONFIG_ZISOFS |
7fa393a1 AM |
511 | case SIG('Z', 'F'): { |
512 | int algo; | |
513 | ||
514 | if (ISOFS_SB(inode->i_sb)->s_nocompress) | |
1d372116 | 515 | break; |
7fa393a1 AM |
516 | algo = isonum_721(rr->u.ZF.algorithm); |
517 | if (algo == SIG('p', 'z')) { | |
518 | int block_shift = | |
519 | isonum_711(&rr->u.ZF.parms[1]); | |
59bc0552 | 520 | if (block_shift > 17) { |
7fa393a1 AM |
521 | printk(KERN_WARNING "isofs: " |
522 | "Can't handle ZF block " | |
523 | "size of 2^%d\n", | |
524 | block_shift); | |
525 | } else { | |
526 | /* | |
527 | * Note: we don't change | |
528 | * i_blocks here | |
529 | */ | |
530 | ISOFS_I(inode)->i_file_format = | |
531 | isofs_file_compressed; | |
532 | /* | |
533 | * Parameters to compression | |
534 | * algorithm (header size, | |
535 | * block size) | |
536 | */ | |
537 | ISOFS_I(inode)->i_format_parm[0] = | |
538 | isonum_711(&rr->u.ZF.parms[0]); | |
539 | ISOFS_I(inode)->i_format_parm[1] = | |
540 | isonum_711(&rr->u.ZF.parms[1]); | |
541 | inode->i_size = | |
542 | isonum_733(rr->u.ZF. | |
543 | real_size); | |
544 | } | |
545 | } else { | |
546 | printk(KERN_WARNING | |
547 | "isofs: Unknown ZF compression " | |
548 | "algorithm: %c%c\n", | |
549 | rr->u.ZF.algorithm[0], | |
550 | rr->u.ZF.algorithm[1]); | |
1d372116 | 551 | } |
7fa393a1 AM |
552 | break; |
553 | } | |
554 | #endif | |
555 | default: | |
556 | break; | |
1d372116 AM |
557 | } |
558 | } | |
ba40aaf0 AM |
559 | ret = rock_continue(&rs); |
560 | if (ret == 0) | |
561 | goto repeat; | |
562 | if (ret == 1) | |
563 | ret = 0; | |
7fa393a1 | 564 | out: |
ba40aaf0 AM |
565 | kfree(rs.buffer); |
566 | return ret; | |
f2966632 AM |
567 | eio: |
568 | ret = -EIO; | |
569 | goto out; | |
1da177e4 LT |
570 | } |
571 | ||
572 | static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit) | |
573 | { | |
574 | int slen; | |
575 | int rootflag; | |
576 | struct SL_component *oldslp; | |
577 | struct SL_component *slp; | |
578 | slen = rr->len - 5; | |
579 | slp = &rr->u.SL.link; | |
580 | while (slen > 1) { | |
581 | rootflag = 0; | |
582 | switch (slp->flags & ~1) { | |
583 | case 0: | |
584 | if (slp->len > plimit - rpnt) | |
585 | return NULL; | |
586 | memcpy(rpnt, slp->text, slp->len); | |
1d372116 | 587 | rpnt += slp->len; |
1da177e4 LT |
588 | break; |
589 | case 2: | |
590 | if (rpnt >= plimit) | |
591 | return NULL; | |
1d372116 | 592 | *rpnt++ = '.'; |
1da177e4 LT |
593 | break; |
594 | case 4: | |
595 | if (2 > plimit - rpnt) | |
596 | return NULL; | |
1d372116 AM |
597 | *rpnt++ = '.'; |
598 | *rpnt++ = '.'; | |
1da177e4 LT |
599 | break; |
600 | case 8: | |
601 | if (rpnt >= plimit) | |
602 | return NULL; | |
603 | rootflag = 1; | |
1d372116 | 604 | *rpnt++ = '/'; |
1da177e4 LT |
605 | break; |
606 | default: | |
607 | printk("Symlink component flag not implemented (%d)\n", | |
1d372116 | 608 | slp->flags); |
1da177e4 LT |
609 | } |
610 | slen -= slp->len + 2; | |
611 | oldslp = slp; | |
1d372116 | 612 | slp = (struct SL_component *)((char *)slp + slp->len + 2); |
1da177e4 LT |
613 | |
614 | if (slen < 2) { | |
615 | /* | |
616 | * If there is another SL record, and this component | |
617 | * record isn't continued, then add a slash. | |
618 | */ | |
619 | if ((!rootflag) && (rr->u.SL.flags & 1) && | |
620 | !(oldslp->flags & 1)) { | |
621 | if (rpnt >= plimit) | |
622 | return NULL; | |
1d372116 | 623 | *rpnt++ = '/'; |
1da177e4 LT |
624 | } |
625 | break; | |
626 | } | |
627 | ||
628 | /* | |
629 | * If this component record isn't continued, then append a '/'. | |
630 | */ | |
631 | if (!rootflag && !(oldslp->flags & 1)) { | |
632 | if (rpnt >= plimit) | |
633 | return NULL; | |
1d372116 | 634 | *rpnt++ = '/'; |
1da177e4 LT |
635 | } |
636 | } | |
637 | return rpnt; | |
638 | } | |
639 | ||
1d372116 | 640 | int parse_rock_ridge_inode(struct iso_directory_record *de, struct inode *inode) |
1da177e4 | 641 | { |
1d372116 | 642 | int result = parse_rock_ridge_inode_internal(de, inode, 0); |
7373909d AM |
643 | |
644 | /* | |
645 | * if rockridge flag was reset and we didn't look for attributes | |
646 | * behind eventual XA attributes, have a look there | |
647 | */ | |
1d372116 AM |
648 | if ((ISOFS_SB(inode->i_sb)->s_rock_offset == -1) |
649 | && (ISOFS_SB(inode->i_sb)->s_rock == 2)) { | |
650 | result = parse_rock_ridge_inode_internal(de, inode, 14); | |
651 | } | |
652 | return result; | |
1da177e4 LT |
653 | } |
654 | ||
7373909d AM |
655 | /* |
656 | * readpage() for symlinks: reads symlink contents into the page and either | |
657 | * makes it uptodate and returns 0 or returns error (-EIO) | |
658 | */ | |
1da177e4 LT |
659 | static int rock_ridge_symlink_readpage(struct file *file, struct page *page) |
660 | { | |
661 | struct inode *inode = page->mapping->host; | |
1d372116 | 662 | struct iso_inode_info *ei = ISOFS_I(inode); |
4f819a78 | 663 | struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb); |
1da177e4 LT |
664 | char *link = kmap(page); |
665 | unsigned long bufsize = ISOFS_BUFFER_SIZE(inode); | |
666 | struct buffer_head *bh; | |
667 | char *rpnt = link; | |
668 | unsigned char *pnt; | |
76ab07eb | 669 | struct iso_directory_record *raw_de; |
1da177e4 LT |
670 | unsigned long block, offset; |
671 | int sig; | |
1da177e4 | 672 | struct rock_ridge *rr; |
ba40aaf0 AM |
673 | struct rock_state rs; |
674 | int ret; | |
1da177e4 | 675 | |
4f819a78 | 676 | if (!sbi->s_rock) |
1da177e4 LT |
677 | goto error; |
678 | ||
ba40aaf0 | 679 | init_rock_state(&rs, inode); |
1da177e4 | 680 | block = ei->i_iget5_block; |
1da177e4 LT |
681 | bh = sb_bread(inode->i_sb, block); |
682 | if (!bh) | |
683 | goto out_noread; | |
684 | ||
1d372116 AM |
685 | offset = ei->i_iget5_offset; |
686 | pnt = (unsigned char *)bh->b_data + offset; | |
1da177e4 | 687 | |
76ab07eb | 688 | raw_de = (struct iso_directory_record *)pnt; |
1da177e4 LT |
689 | |
690 | /* | |
691 | * If we go past the end of the buffer, there is some sort of error. | |
692 | */ | |
693 | if (offset + *pnt > bufsize) | |
694 | goto out_bad_span; | |
695 | ||
7373909d AM |
696 | /* |
697 | * Now test for possible Rock Ridge extensions which will override | |
698 | * some of these numbers in the inode structure. | |
699 | */ | |
1da177e4 | 700 | |
ba40aaf0 | 701 | setup_rock_ridge(raw_de, inode, &rs); |
1da177e4 | 702 | |
7fa393a1 | 703 | repeat: |
ba40aaf0 AM |
704 | while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
705 | rr = (struct rock_ridge *)rs.chr; | |
1da177e4 LT |
706 | if (rr->len < 3) |
707 | goto out; /* Something got screwed up here */ | |
ba40aaf0 | 708 | sig = isonum_721(rs.chr); |
f2966632 AM |
709 | if (rock_check_overflow(&rs, sig)) |
710 | goto out; | |
ba40aaf0 AM |
711 | rs.chr += rr->len; |
712 | rs.len -= rr->len; | |
713 | if (rs.len < 0) | |
1da177e4 LT |
714 | goto out; /* corrupted isofs */ |
715 | ||
716 | switch (sig) { | |
717 | case SIG('R', 'R'): | |
718 | if ((rr->u.RR.flags[0] & RR_SL) == 0) | |
719 | goto out; | |
720 | break; | |
721 | case SIG('S', 'P'): | |
12121714 AM |
722 | if (check_sp(rr, inode)) |
723 | goto out; | |
1da177e4 LT |
724 | break; |
725 | case SIG('S', 'L'): | |
726 | rpnt = get_symlink_chunk(rpnt, rr, | |
727 | link + (PAGE_SIZE - 1)); | |
728 | if (rpnt == NULL) | |
729 | goto out; | |
730 | break; | |
731 | case SIG('C', 'E'): | |
732 | /* This tells is if there is a continuation record */ | |
ba40aaf0 AM |
733 | rs.cont_extent = isonum_733(rr->u.CE.extent); |
734 | rs.cont_offset = isonum_733(rr->u.CE.offset); | |
735 | rs.cont_size = isonum_733(rr->u.CE.size); | |
1da177e4 LT |
736 | default: |
737 | break; | |
738 | } | |
739 | } | |
ba40aaf0 AM |
740 | ret = rock_continue(&rs); |
741 | if (ret == 0) | |
742 | goto repeat; | |
743 | if (ret < 0) | |
744 | goto fail; | |
1da177e4 LT |
745 | |
746 | if (rpnt == link) | |
747 | goto fail; | |
748 | brelse(bh); | |
749 | *rpnt = '\0'; | |
1da177e4 LT |
750 | SetPageUptodate(page); |
751 | kunmap(page); | |
752 | unlock_page(page); | |
753 | return 0; | |
754 | ||
755 | /* error exit from macro */ | |
7fa393a1 | 756 | out: |
ba40aaf0 | 757 | kfree(rs.buffer); |
1da177e4 | 758 | goto fail; |
7fa393a1 | 759 | out_noread: |
1da177e4 LT |
760 | printk("unable to read i-node block"); |
761 | goto fail; | |
7fa393a1 | 762 | out_bad_span: |
1da177e4 | 763 | printk("symlink spans iso9660 blocks\n"); |
7fa393a1 | 764 | fail: |
1da177e4 | 765 | brelse(bh); |
7fa393a1 | 766 | error: |
1da177e4 LT |
767 | SetPageError(page); |
768 | kunmap(page); | |
769 | unlock_page(page); | |
770 | return -EIO; | |
771 | } | |
772 | ||
f5e54d6e | 773 | const struct address_space_operations isofs_symlink_aops = { |
1d372116 | 774 | .readpage = rock_ridge_symlink_readpage |
1da177e4 | 775 | }; |