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1da177e4 LT |
1 | #define MSNFS /* HACK HACK */ |
2 | /* | |
3 | * linux/fs/nfsd/export.c | |
4 | * | |
5 | * NFS exporting and validation. | |
6 | * | |
7 | * We maintain a list of clients, each of which has a list of | |
8 | * exports. To export an fs to a given client, you first have | |
9 | * to create the client entry with NFSCTL_ADDCLIENT, which | |
10 | * creates a client control block and adds it to the hash | |
11 | * table. Then, you call NFSCTL_EXPORT for each fs. | |
12 | * | |
13 | * | |
14 | * Copyright (C) 1995, 1996 Olaf Kirch, <okir@monad.swb.de> | |
15 | */ | |
16 | ||
17 | #include <linux/unistd.h> | |
18 | #include <linux/slab.h> | |
19 | #include <linux/sched.h> | |
20 | #include <linux/stat.h> | |
21 | #include <linux/in.h> | |
22 | #include <linux/seq_file.h> | |
23 | #include <linux/syscalls.h> | |
24 | #include <linux/rwsem.h> | |
25 | #include <linux/dcache.h> | |
26 | #include <linux/namei.h> | |
27 | #include <linux/mount.h> | |
28 | #include <linux/hash.h> | |
29 | ||
30 | #include <linux/sunrpc/svc.h> | |
31 | #include <linux/nfsd/nfsd.h> | |
32 | #include <linux/nfsd/nfsfh.h> | |
33 | #include <linux/nfsd/syscall.h> | |
34 | #include <linux/lockd/bind.h> | |
35 | ||
36 | #define NFSDDBG_FACILITY NFSDDBG_EXPORT | |
37 | #define NFSD_PARANOIA 1 | |
38 | ||
39 | typedef struct auth_domain svc_client; | |
40 | typedef struct svc_export svc_export; | |
41 | ||
42 | static void exp_do_unexport(svc_export *unexp); | |
43 | static int exp_verify_string(char *cp, int max); | |
44 | ||
45 | /* | |
46 | * We have two caches. | |
47 | * One maps client+vfsmnt+dentry to export options - the export map | |
48 | * The other maps client+filehandle-fragment to export options. - the expkey map | |
49 | * | |
50 | * The export options are actually stored in the first map, and the | |
51 | * second map contains a reference to the entry in the first map. | |
52 | */ | |
53 | ||
54 | #define EXPKEY_HASHBITS 8 | |
55 | #define EXPKEY_HASHMAX (1 << EXPKEY_HASHBITS) | |
56 | #define EXPKEY_HASHMASK (EXPKEY_HASHMAX -1) | |
57 | static struct cache_head *expkey_table[EXPKEY_HASHMAX]; | |
58 | ||
59 | static inline int svc_expkey_hash(struct svc_expkey *item) | |
60 | { | |
61 | int hash = item->ek_fsidtype; | |
62 | char * cp = (char*)item->ek_fsid; | |
63 | int len = key_len(item->ek_fsidtype); | |
64 | ||
65 | hash ^= hash_mem(cp, len, EXPKEY_HASHBITS); | |
66 | hash ^= hash_ptr(item->ek_client, EXPKEY_HASHBITS); | |
67 | return hash & EXPKEY_HASHMASK; | |
68 | } | |
69 | ||
70 | void expkey_put(struct cache_head *item, struct cache_detail *cd) | |
71 | { | |
72 | if (cache_put(item, cd)) { | |
73 | struct svc_expkey *key = container_of(item, struct svc_expkey, h); | |
74 | if (test_bit(CACHE_VALID, &item->flags) && | |
75 | !test_bit(CACHE_NEGATIVE, &item->flags)) | |
76 | exp_put(key->ek_export); | |
77 | auth_domain_put(key->ek_client); | |
78 | kfree(key); | |
79 | } | |
80 | } | |
81 | ||
82 | static void expkey_request(struct cache_detail *cd, | |
83 | struct cache_head *h, | |
84 | char **bpp, int *blen) | |
85 | { | |
86 | /* client fsidtype \xfsid */ | |
87 | struct svc_expkey *ek = container_of(h, struct svc_expkey, h); | |
88 | char type[5]; | |
89 | ||
90 | qword_add(bpp, blen, ek->ek_client->name); | |
91 | snprintf(type, 5, "%d", ek->ek_fsidtype); | |
92 | qword_add(bpp, blen, type); | |
93 | qword_addhex(bpp, blen, (char*)ek->ek_fsid, key_len(ek->ek_fsidtype)); | |
94 | (*bpp)[-1] = '\n'; | |
95 | } | |
96 | ||
97 | static struct svc_expkey *svc_expkey_lookup(struct svc_expkey *, int); | |
98 | static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen) | |
99 | { | |
100 | /* client fsidtype fsid [path] */ | |
101 | char *buf; | |
102 | int len; | |
103 | struct auth_domain *dom = NULL; | |
104 | int err; | |
105 | int fsidtype; | |
106 | char *ep; | |
107 | struct svc_expkey key; | |
108 | ||
109 | if (mesg[mlen-1] != '\n') | |
110 | return -EINVAL; | |
111 | mesg[mlen-1] = 0; | |
112 | ||
113 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
114 | err = -ENOMEM; | |
115 | if (!buf) goto out; | |
116 | ||
117 | err = -EINVAL; | |
118 | if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0) | |
119 | goto out; | |
120 | ||
121 | err = -ENOENT; | |
122 | dom = auth_domain_find(buf); | |
123 | if (!dom) | |
124 | goto out; | |
125 | dprintk("found domain %s\n", buf); | |
126 | ||
127 | err = -EINVAL; | |
128 | if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0) | |
129 | goto out; | |
130 | fsidtype = simple_strtoul(buf, &ep, 10); | |
131 | if (*ep) | |
132 | goto out; | |
133 | dprintk("found fsidtype %d\n", fsidtype); | |
134 | if (fsidtype > 2) | |
135 | goto out; | |
136 | if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0) | |
137 | goto out; | |
138 | dprintk("found fsid length %d\n", len); | |
139 | if (len != key_len(fsidtype)) | |
140 | goto out; | |
141 | ||
142 | /* OK, we seem to have a valid key */ | |
143 | key.h.flags = 0; | |
144 | key.h.expiry_time = get_expiry(&mesg); | |
145 | if (key.h.expiry_time == 0) | |
146 | goto out; | |
147 | ||
148 | key.ek_client = dom; | |
149 | key.ek_fsidtype = fsidtype; | |
150 | memcpy(key.ek_fsid, buf, len); | |
151 | ||
152 | /* now we want a pathname, or empty meaning NEGATIVE */ | |
153 | if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0) | |
154 | goto out; | |
155 | dprintk("Path seems to be <%s>\n", buf); | |
156 | err = 0; | |
157 | if (len == 0) { | |
158 | struct svc_expkey *ek; | |
159 | set_bit(CACHE_NEGATIVE, &key.h.flags); | |
160 | ek = svc_expkey_lookup(&key, 1); | |
161 | if (ek) | |
162 | expkey_put(&ek->h, &svc_expkey_cache); | |
163 | } else { | |
164 | struct nameidata nd; | |
165 | struct svc_expkey *ek; | |
166 | struct svc_export *exp; | |
167 | err = path_lookup(buf, 0, &nd); | |
168 | if (err) | |
169 | goto out; | |
170 | ||
171 | dprintk("Found the path %s\n", buf); | |
172 | exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL); | |
173 | ||
174 | err = -ENOENT; | |
175 | if (!exp) | |
176 | goto out_nd; | |
177 | key.ek_export = exp; | |
178 | dprintk("And found export\n"); | |
179 | ||
180 | ek = svc_expkey_lookup(&key, 1); | |
181 | if (ek) | |
182 | expkey_put(&ek->h, &svc_expkey_cache); | |
183 | exp_put(exp); | |
184 | err = 0; | |
185 | out_nd: | |
186 | path_release(&nd); | |
187 | } | |
188 | cache_flush(); | |
189 | out: | |
190 | if (dom) | |
191 | auth_domain_put(dom); | |
192 | if (buf) | |
193 | kfree(buf); | |
194 | return err; | |
195 | } | |
196 | ||
197 | static int expkey_show(struct seq_file *m, | |
198 | struct cache_detail *cd, | |
199 | struct cache_head *h) | |
200 | { | |
201 | struct svc_expkey *ek ; | |
202 | ||
203 | if (h ==NULL) { | |
204 | seq_puts(m, "#domain fsidtype fsid [path]\n"); | |
205 | return 0; | |
206 | } | |
207 | ek = container_of(h, struct svc_expkey, h); | |
208 | seq_printf(m, "%s %d 0x%08x", ek->ek_client->name, | |
209 | ek->ek_fsidtype, ek->ek_fsid[0]); | |
210 | if (ek->ek_fsidtype != 1) | |
211 | seq_printf(m, "%08x", ek->ek_fsid[1]); | |
212 | if (ek->ek_fsidtype == 2) | |
213 | seq_printf(m, "%08x", ek->ek_fsid[2]); | |
214 | if (test_bit(CACHE_VALID, &h->flags) && | |
215 | !test_bit(CACHE_NEGATIVE, &h->flags)) { | |
216 | seq_printf(m, " "); | |
217 | seq_path(m, ek->ek_export->ex_mnt, ek->ek_export->ex_dentry, "\\ \t\n"); | |
218 | } | |
219 | seq_printf(m, "\n"); | |
220 | return 0; | |
221 | } | |
222 | ||
223 | struct cache_detail svc_expkey_cache = { | |
224 | .hash_size = EXPKEY_HASHMAX, | |
225 | .hash_table = expkey_table, | |
226 | .name = "nfsd.fh", | |
227 | .cache_put = expkey_put, | |
228 | .cache_request = expkey_request, | |
229 | .cache_parse = expkey_parse, | |
230 | .cache_show = expkey_show, | |
231 | }; | |
232 | ||
233 | static inline int svc_expkey_match (struct svc_expkey *a, struct svc_expkey *b) | |
234 | { | |
235 | if (a->ek_fsidtype != b->ek_fsidtype || | |
236 | a->ek_client != b->ek_client || | |
237 | memcmp(a->ek_fsid, b->ek_fsid, key_len(a->ek_fsidtype)) != 0) | |
238 | return 0; | |
239 | return 1; | |
240 | } | |
241 | ||
242 | static inline void svc_expkey_init(struct svc_expkey *new, struct svc_expkey *item) | |
243 | { | |
244 | cache_get(&item->ek_client->h); | |
245 | new->ek_client = item->ek_client; | |
246 | new->ek_fsidtype = item->ek_fsidtype; | |
247 | new->ek_fsid[0] = item->ek_fsid[0]; | |
248 | new->ek_fsid[1] = item->ek_fsid[1]; | |
249 | new->ek_fsid[2] = item->ek_fsid[2]; | |
250 | } | |
251 | ||
252 | static inline void svc_expkey_update(struct svc_expkey *new, struct svc_expkey *item) | |
253 | { | |
254 | cache_get(&item->ek_export->h); | |
255 | new->ek_export = item->ek_export; | |
256 | } | |
257 | ||
258 | static DefineSimpleCacheLookup(svc_expkey,0) /* no inplace updates */ | |
259 | ||
260 | #define EXPORT_HASHBITS 8 | |
261 | #define EXPORT_HASHMAX (1<< EXPORT_HASHBITS) | |
262 | #define EXPORT_HASHMASK (EXPORT_HASHMAX -1) | |
263 | ||
264 | static struct cache_head *export_table[EXPORT_HASHMAX]; | |
265 | ||
266 | static inline int svc_export_hash(struct svc_export *item) | |
267 | { | |
268 | int rv; | |
269 | ||
270 | rv = hash_ptr(item->ex_client, EXPORT_HASHBITS); | |
271 | rv ^= hash_ptr(item->ex_dentry, EXPORT_HASHBITS); | |
272 | rv ^= hash_ptr(item->ex_mnt, EXPORT_HASHBITS); | |
273 | return rv; | |
274 | } | |
275 | ||
276 | void svc_export_put(struct cache_head *item, struct cache_detail *cd) | |
277 | { | |
278 | if (cache_put(item, cd)) { | |
279 | struct svc_export *exp = container_of(item, struct svc_export, h); | |
280 | dput(exp->ex_dentry); | |
281 | mntput(exp->ex_mnt); | |
282 | auth_domain_put(exp->ex_client); | |
283 | kfree(exp); | |
284 | } | |
285 | } | |
286 | ||
287 | static void svc_export_request(struct cache_detail *cd, | |
288 | struct cache_head *h, | |
289 | char **bpp, int *blen) | |
290 | { | |
291 | /* client path */ | |
292 | struct svc_export *exp = container_of(h, struct svc_export, h); | |
293 | char *pth; | |
294 | ||
295 | qword_add(bpp, blen, exp->ex_client->name); | |
296 | pth = d_path(exp->ex_dentry, exp->ex_mnt, *bpp, *blen); | |
297 | if (IS_ERR(pth)) { | |
298 | /* is this correct? */ | |
299 | (*bpp)[0] = '\n'; | |
300 | return; | |
301 | } | |
302 | qword_add(bpp, blen, pth); | |
303 | (*bpp)[-1] = '\n'; | |
304 | } | |
305 | ||
306 | static struct svc_export *svc_export_lookup(struct svc_export *, int); | |
307 | ||
308 | static int check_export(struct inode *inode, int flags) | |
309 | { | |
310 | ||
311 | /* We currently export only dirs and regular files. | |
312 | * This is what umountd does. | |
313 | */ | |
314 | if (!S_ISDIR(inode->i_mode) && | |
315 | !S_ISREG(inode->i_mode)) | |
316 | return -ENOTDIR; | |
317 | ||
318 | /* There are two requirements on a filesystem to be exportable. | |
319 | * 1: We must be able to identify the filesystem from a number. | |
320 | * either a device number (so FS_REQUIRES_DEV needed) | |
321 | * or an FSID number (so NFSEXP_FSID needed). | |
322 | * 2: We must be able to find an inode from a filehandle. | |
323 | * This means that s_export_op must be set. | |
324 | */ | |
325 | if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) && | |
326 | !(flags & NFSEXP_FSID)) { | |
327 | dprintk("exp_export: export of non-dev fs without fsid"); | |
328 | return -EINVAL; | |
329 | } | |
330 | if (!inode->i_sb->s_export_op) { | |
331 | dprintk("exp_export: export of invalid fs type.\n"); | |
332 | return -EINVAL; | |
333 | } | |
334 | ||
335 | /* Ok, we can export it */; | |
336 | if (!inode->i_sb->s_export_op->find_exported_dentry) | |
337 | inode->i_sb->s_export_op->find_exported_dentry = | |
338 | find_exported_dentry; | |
339 | return 0; | |
340 | ||
341 | } | |
342 | ||
343 | static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen) | |
344 | { | |
345 | /* client path expiry [flags anonuid anongid fsid] */ | |
346 | char *buf; | |
347 | int len; | |
348 | int err; | |
349 | struct auth_domain *dom = NULL; | |
350 | struct nameidata nd; | |
351 | struct svc_export exp, *expp; | |
352 | int an_int; | |
353 | ||
354 | nd.dentry = NULL; | |
355 | ||
356 | if (mesg[mlen-1] != '\n') | |
357 | return -EINVAL; | |
358 | mesg[mlen-1] = 0; | |
359 | ||
360 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
361 | err = -ENOMEM; | |
362 | if (!buf) goto out; | |
363 | ||
364 | /* client */ | |
365 | len = qword_get(&mesg, buf, PAGE_SIZE); | |
366 | err = -EINVAL; | |
367 | if (len <= 0) goto out; | |
368 | ||
369 | err = -ENOENT; | |
370 | dom = auth_domain_find(buf); | |
371 | if (!dom) | |
372 | goto out; | |
373 | ||
374 | /* path */ | |
375 | err = -EINVAL; | |
376 | if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0) | |
377 | goto out; | |
378 | err = path_lookup(buf, 0, &nd); | |
379 | if (err) goto out; | |
380 | ||
381 | exp.h.flags = 0; | |
382 | exp.ex_client = dom; | |
383 | exp.ex_mnt = nd.mnt; | |
384 | exp.ex_dentry = nd.dentry; | |
385 | ||
386 | /* expiry */ | |
387 | err = -EINVAL; | |
388 | exp.h.expiry_time = get_expiry(&mesg); | |
389 | if (exp.h.expiry_time == 0) | |
390 | goto out; | |
391 | ||
392 | /* flags */ | |
393 | err = get_int(&mesg, &an_int); | |
394 | if (err == -ENOENT) | |
395 | set_bit(CACHE_NEGATIVE, &exp.h.flags); | |
396 | else { | |
397 | if (err || an_int < 0) goto out; | |
398 | exp.ex_flags= an_int; | |
399 | ||
400 | /* anon uid */ | |
401 | err = get_int(&mesg, &an_int); | |
402 | if (err) goto out; | |
403 | exp.ex_anon_uid= an_int; | |
404 | ||
405 | /* anon gid */ | |
406 | err = get_int(&mesg, &an_int); | |
407 | if (err) goto out; | |
408 | exp.ex_anon_gid= an_int; | |
409 | ||
410 | /* fsid */ | |
411 | err = get_int(&mesg, &an_int); | |
412 | if (err) goto out; | |
413 | exp.ex_fsid = an_int; | |
414 | ||
415 | err = check_export(nd.dentry->d_inode, exp.ex_flags); | |
416 | if (err) goto out; | |
417 | } | |
418 | ||
419 | expp = svc_export_lookup(&exp, 1); | |
420 | if (expp) | |
421 | exp_put(expp); | |
422 | err = 0; | |
423 | cache_flush(); | |
424 | out: | |
425 | if (nd.dentry) | |
426 | path_release(&nd); | |
427 | if (dom) | |
428 | auth_domain_put(dom); | |
429 | if (buf) | |
430 | kfree(buf); | |
431 | return err; | |
432 | } | |
433 | ||
434 | static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong); | |
435 | ||
436 | static int svc_export_show(struct seq_file *m, | |
437 | struct cache_detail *cd, | |
438 | struct cache_head *h) | |
439 | { | |
440 | struct svc_export *exp ; | |
441 | ||
442 | if (h ==NULL) { | |
443 | seq_puts(m, "#path domain(flags)\n"); | |
444 | return 0; | |
445 | } | |
446 | exp = container_of(h, struct svc_export, h); | |
447 | seq_path(m, exp->ex_mnt, exp->ex_dentry, " \t\n\\"); | |
448 | seq_putc(m, '\t'); | |
449 | seq_escape(m, exp->ex_client->name, " \t\n\\"); | |
450 | seq_putc(m, '('); | |
451 | if (test_bit(CACHE_VALID, &h->flags) && | |
452 | !test_bit(CACHE_NEGATIVE, &h->flags)) | |
453 | exp_flags(m, exp->ex_flags, exp->ex_fsid, | |
454 | exp->ex_anon_uid, exp->ex_anon_gid); | |
455 | seq_puts(m, ")\n"); | |
456 | return 0; | |
457 | } | |
458 | struct cache_detail svc_export_cache = { | |
459 | .hash_size = EXPORT_HASHMAX, | |
460 | .hash_table = export_table, | |
461 | .name = "nfsd.export", | |
462 | .cache_put = svc_export_put, | |
463 | .cache_request = svc_export_request, | |
464 | .cache_parse = svc_export_parse, | |
465 | .cache_show = svc_export_show, | |
466 | }; | |
467 | ||
468 | static inline int svc_export_match(struct svc_export *a, struct svc_export *b) | |
469 | { | |
470 | return a->ex_client == b->ex_client && | |
471 | a->ex_dentry == b->ex_dentry && | |
472 | a->ex_mnt == b->ex_mnt; | |
473 | } | |
474 | static inline void svc_export_init(struct svc_export *new, struct svc_export *item) | |
475 | { | |
476 | cache_get(&item->ex_client->h); | |
477 | new->ex_client = item->ex_client; | |
478 | new->ex_dentry = dget(item->ex_dentry); | |
479 | new->ex_mnt = mntget(item->ex_mnt); | |
480 | } | |
481 | ||
482 | static inline void svc_export_update(struct svc_export *new, struct svc_export *item) | |
483 | { | |
484 | new->ex_flags = item->ex_flags; | |
485 | new->ex_anon_uid = item->ex_anon_uid; | |
486 | new->ex_anon_gid = item->ex_anon_gid; | |
487 | new->ex_fsid = item->ex_fsid; | |
488 | } | |
489 | ||
490 | static DefineSimpleCacheLookup(svc_export,1) /* allow inplace updates */ | |
491 | ||
492 | ||
493 | struct svc_expkey * | |
494 | exp_find_key(svc_client *clp, int fsid_type, u32 *fsidv, struct cache_req *reqp) | |
495 | { | |
496 | struct svc_expkey key, *ek; | |
497 | int err; | |
498 | ||
499 | if (!clp) | |
500 | return NULL; | |
501 | ||
502 | key.ek_client = clp; | |
503 | key.ek_fsidtype = fsid_type; | |
504 | memcpy(key.ek_fsid, fsidv, key_len(fsid_type)); | |
505 | ||
506 | ek = svc_expkey_lookup(&key, 0); | |
507 | if (ek != NULL) | |
508 | if ((err = cache_check(&svc_expkey_cache, &ek->h, reqp))) | |
509 | ek = ERR_PTR(err); | |
510 | return ek; | |
511 | } | |
512 | ||
513 | static int exp_set_key(svc_client *clp, int fsid_type, u32 *fsidv, | |
514 | struct svc_export *exp) | |
515 | { | |
516 | struct svc_expkey key, *ek; | |
517 | ||
518 | key.ek_client = clp; | |
519 | key.ek_fsidtype = fsid_type; | |
520 | memcpy(key.ek_fsid, fsidv, key_len(fsid_type)); | |
521 | key.ek_export = exp; | |
522 | key.h.expiry_time = NEVER; | |
523 | key.h.flags = 0; | |
524 | ||
525 | ek = svc_expkey_lookup(&key, 1); | |
526 | if (ek) { | |
527 | expkey_put(&ek->h, &svc_expkey_cache); | |
528 | return 0; | |
529 | } | |
530 | return -ENOMEM; | |
531 | } | |
532 | ||
533 | /* | |
534 | * Find the client's export entry matching xdev/xino. | |
535 | */ | |
536 | static inline struct svc_expkey * | |
537 | exp_get_key(svc_client *clp, dev_t dev, ino_t ino) | |
538 | { | |
539 | u32 fsidv[3]; | |
540 | ||
541 | if (old_valid_dev(dev)) { | |
542 | mk_fsid_v0(fsidv, dev, ino); | |
543 | return exp_find_key(clp, 0, fsidv, NULL); | |
544 | } | |
545 | mk_fsid_v3(fsidv, dev, ino); | |
546 | return exp_find_key(clp, 3, fsidv, NULL); | |
547 | } | |
548 | ||
549 | /* | |
550 | * Find the client's export entry matching fsid | |
551 | */ | |
552 | static inline struct svc_expkey * | |
553 | exp_get_fsid_key(svc_client *clp, int fsid) | |
554 | { | |
555 | u32 fsidv[2]; | |
556 | ||
557 | mk_fsid_v1(fsidv, fsid); | |
558 | ||
559 | return exp_find_key(clp, 1, fsidv, NULL); | |
560 | } | |
561 | ||
562 | svc_export * | |
563 | exp_get_by_name(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry, | |
564 | struct cache_req *reqp) | |
565 | { | |
566 | struct svc_export *exp, key; | |
567 | ||
568 | if (!clp) | |
569 | return NULL; | |
570 | ||
571 | key.ex_client = clp; | |
572 | key.ex_mnt = mnt; | |
573 | key.ex_dentry = dentry; | |
574 | ||
575 | exp = svc_export_lookup(&key, 0); | |
576 | if (exp != NULL) | |
577 | switch (cache_check(&svc_export_cache, &exp->h, reqp)) { | |
578 | case 0: break; | |
579 | case -EAGAIN: | |
580 | exp = ERR_PTR(-EAGAIN); | |
581 | break; | |
582 | default: | |
583 | exp = NULL; | |
584 | } | |
585 | ||
586 | return exp; | |
587 | } | |
588 | ||
589 | /* | |
590 | * Find the export entry for a given dentry. | |
591 | */ | |
592 | struct svc_export * | |
593 | exp_parent(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry, | |
594 | struct cache_req *reqp) | |
595 | { | |
596 | svc_export *exp; | |
597 | ||
598 | dget(dentry); | |
599 | exp = exp_get_by_name(clp, mnt, dentry, reqp); | |
600 | ||
601 | while (exp == NULL && !IS_ROOT(dentry)) { | |
602 | struct dentry *parent; | |
603 | ||
604 | parent = dget_parent(dentry); | |
605 | dput(dentry); | |
606 | dentry = parent; | |
607 | exp = exp_get_by_name(clp, mnt, dentry, reqp); | |
608 | } | |
609 | dput(dentry); | |
610 | return exp; | |
611 | } | |
612 | ||
613 | /* | |
614 | * Hashtable locking. Write locks are placed only by user processes | |
615 | * wanting to modify export information. | |
616 | * Write locking only done in this file. Read locking | |
617 | * needed externally. | |
618 | */ | |
619 | ||
620 | static DECLARE_RWSEM(hash_sem); | |
621 | ||
622 | void | |
623 | exp_readlock(void) | |
624 | { | |
625 | down_read(&hash_sem); | |
626 | } | |
627 | ||
628 | static inline void | |
629 | exp_writelock(void) | |
630 | { | |
631 | down_write(&hash_sem); | |
632 | } | |
633 | ||
634 | void | |
635 | exp_readunlock(void) | |
636 | { | |
637 | up_read(&hash_sem); | |
638 | } | |
639 | ||
640 | static inline void | |
641 | exp_writeunlock(void) | |
642 | { | |
643 | up_write(&hash_sem); | |
644 | } | |
645 | ||
646 | static void exp_fsid_unhash(struct svc_export *exp) | |
647 | { | |
648 | struct svc_expkey *ek; | |
649 | ||
650 | if ((exp->ex_flags & NFSEXP_FSID) == 0) | |
651 | return; | |
652 | ||
653 | ek = exp_get_fsid_key(exp->ex_client, exp->ex_fsid); | |
654 | if (ek && !IS_ERR(ek)) { | |
655 | ek->h.expiry_time = get_seconds()-1; | |
656 | expkey_put(&ek->h, &svc_expkey_cache); | |
657 | } | |
658 | svc_expkey_cache.nextcheck = get_seconds(); | |
659 | } | |
660 | ||
661 | static int exp_fsid_hash(svc_client *clp, struct svc_export *exp) | |
662 | { | |
663 | u32 fsid[2]; | |
664 | ||
665 | if ((exp->ex_flags & NFSEXP_FSID) == 0) | |
666 | return 0; | |
667 | ||
668 | mk_fsid_v1(fsid, exp->ex_fsid); | |
669 | return exp_set_key(clp, 1, fsid, exp); | |
670 | } | |
671 | ||
672 | static int exp_hash(struct auth_domain *clp, struct svc_export *exp) | |
673 | { | |
674 | u32 fsid[2]; | |
675 | struct inode *inode = exp->ex_dentry->d_inode; | |
676 | dev_t dev = inode->i_sb->s_dev; | |
677 | ||
678 | if (old_valid_dev(dev)) { | |
679 | mk_fsid_v0(fsid, dev, inode->i_ino); | |
680 | return exp_set_key(clp, 0, fsid, exp); | |
681 | } | |
682 | mk_fsid_v3(fsid, dev, inode->i_ino); | |
683 | return exp_set_key(clp, 3, fsid, exp); | |
684 | } | |
685 | ||
686 | static void exp_unhash(struct svc_export *exp) | |
687 | { | |
688 | struct svc_expkey *ek; | |
689 | struct inode *inode = exp->ex_dentry->d_inode; | |
690 | ||
691 | ek = exp_get_key(exp->ex_client, inode->i_sb->s_dev, inode->i_ino); | |
692 | if (ek && !IS_ERR(ek)) { | |
693 | ek->h.expiry_time = get_seconds()-1; | |
694 | expkey_put(&ek->h, &svc_expkey_cache); | |
695 | } | |
696 | svc_expkey_cache.nextcheck = get_seconds(); | |
697 | } | |
698 | ||
699 | /* | |
700 | * Export a file system. | |
701 | */ | |
702 | int | |
703 | exp_export(struct nfsctl_export *nxp) | |
704 | { | |
705 | svc_client *clp; | |
706 | struct svc_export *exp = NULL; | |
707 | struct svc_export new; | |
708 | struct svc_expkey *fsid_key = NULL; | |
709 | struct nameidata nd; | |
710 | int err; | |
711 | ||
712 | /* Consistency check */ | |
713 | err = -EINVAL; | |
714 | if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) || | |
715 | !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX)) | |
716 | goto out; | |
717 | ||
718 | dprintk("exp_export called for %s:%s (%x/%ld fl %x).\n", | |
719 | nxp->ex_client, nxp->ex_path, | |
720 | (unsigned)nxp->ex_dev, (long)nxp->ex_ino, | |
721 | nxp->ex_flags); | |
722 | ||
723 | /* Try to lock the export table for update */ | |
724 | exp_writelock(); | |
725 | ||
726 | /* Look up client info */ | |
727 | if (!(clp = auth_domain_find(nxp->ex_client))) | |
728 | goto out_unlock; | |
729 | ||
730 | ||
731 | /* Look up the dentry */ | |
732 | err = path_lookup(nxp->ex_path, 0, &nd); | |
733 | if (err) | |
734 | goto out_unlock; | |
735 | err = -EINVAL; | |
736 | ||
737 | exp = exp_get_by_name(clp, nd.mnt, nd.dentry, NULL); | |
738 | ||
739 | /* must make sure there won't be an ex_fsid clash */ | |
740 | if ((nxp->ex_flags & NFSEXP_FSID) && | |
741 | (fsid_key = exp_get_fsid_key(clp, nxp->ex_dev)) && | |
742 | !IS_ERR(fsid_key) && | |
743 | fsid_key->ek_export && | |
744 | fsid_key->ek_export != exp) | |
745 | goto finish; | |
746 | ||
747 | if (exp) { | |
748 | /* just a flags/id/fsid update */ | |
749 | ||
750 | exp_fsid_unhash(exp); | |
751 | exp->ex_flags = nxp->ex_flags; | |
752 | exp->ex_anon_uid = nxp->ex_anon_uid; | |
753 | exp->ex_anon_gid = nxp->ex_anon_gid; | |
754 | exp->ex_fsid = nxp->ex_dev; | |
755 | ||
756 | err = exp_fsid_hash(clp, exp); | |
757 | goto finish; | |
758 | } | |
759 | ||
760 | err = check_export(nd.dentry->d_inode, nxp->ex_flags); | |
761 | if (err) goto finish; | |
762 | ||
763 | err = -ENOMEM; | |
764 | ||
765 | dprintk("nfsd: creating export entry %p for client %p\n", exp, clp); | |
766 | ||
767 | new.h.expiry_time = NEVER; | |
768 | new.h.flags = 0; | |
769 | new.ex_client = clp; | |
770 | new.ex_mnt = nd.mnt; | |
771 | new.ex_dentry = nd.dentry; | |
772 | new.ex_flags = nxp->ex_flags; | |
773 | new.ex_anon_uid = nxp->ex_anon_uid; | |
774 | new.ex_anon_gid = nxp->ex_anon_gid; | |
775 | new.ex_fsid = nxp->ex_dev; | |
776 | ||
777 | exp = svc_export_lookup(&new, 1); | |
778 | ||
779 | if (exp == NULL) | |
780 | goto finish; | |
781 | ||
782 | err = 0; | |
783 | ||
784 | if (exp_hash(clp, exp) || | |
785 | exp_fsid_hash(clp, exp)) { | |
786 | /* failed to create at least one index */ | |
787 | exp_do_unexport(exp); | |
788 | cache_flush(); | |
789 | err = -ENOMEM; | |
790 | } | |
791 | ||
792 | finish: | |
793 | if (exp) | |
794 | exp_put(exp); | |
795 | if (fsid_key && !IS_ERR(fsid_key)) | |
796 | expkey_put(&fsid_key->h, &svc_expkey_cache); | |
797 | if (clp) | |
798 | auth_domain_put(clp); | |
799 | path_release(&nd); | |
800 | out_unlock: | |
801 | exp_writeunlock(); | |
802 | out: | |
803 | return err; | |
804 | } | |
805 | ||
806 | /* | |
807 | * Unexport a file system. The export entry has already | |
808 | * been removed from the client's list of exported fs's. | |
809 | */ | |
810 | static void | |
811 | exp_do_unexport(svc_export *unexp) | |
812 | { | |
813 | unexp->h.expiry_time = get_seconds()-1; | |
814 | svc_export_cache.nextcheck = get_seconds(); | |
815 | exp_unhash(unexp); | |
816 | exp_fsid_unhash(unexp); | |
817 | } | |
818 | ||
819 | ||
820 | /* | |
821 | * unexport syscall. | |
822 | */ | |
823 | int | |
824 | exp_unexport(struct nfsctl_export *nxp) | |
825 | { | |
826 | struct auth_domain *dom; | |
827 | svc_export *exp; | |
828 | struct nameidata nd; | |
829 | int err; | |
830 | ||
831 | /* Consistency check */ | |
832 | if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) || | |
833 | !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX)) | |
834 | return -EINVAL; | |
835 | ||
836 | exp_writelock(); | |
837 | ||
838 | err = -EINVAL; | |
839 | dom = auth_domain_find(nxp->ex_client); | |
840 | if (!dom) { | |
841 | dprintk("nfsd: unexport couldn't find %s\n", nxp->ex_client); | |
842 | goto out_unlock; | |
843 | } | |
844 | ||
845 | err = path_lookup(nxp->ex_path, 0, &nd); | |
846 | if (err) | |
847 | goto out_domain; | |
848 | ||
849 | err = -EINVAL; | |
850 | exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL); | |
851 | path_release(&nd); | |
852 | if (!exp) | |
853 | goto out_domain; | |
854 | ||
855 | exp_do_unexport(exp); | |
856 | exp_put(exp); | |
857 | err = 0; | |
858 | ||
859 | out_domain: | |
860 | auth_domain_put(dom); | |
861 | cache_flush(); | |
862 | out_unlock: | |
863 | exp_writeunlock(); | |
864 | return err; | |
865 | } | |
866 | ||
867 | /* | |
868 | * Obtain the root fh on behalf of a client. | |
869 | * This could be done in user space, but I feel that it adds some safety | |
870 | * since its harder to fool a kernel module than a user space program. | |
871 | */ | |
872 | int | |
873 | exp_rootfh(svc_client *clp, char *path, struct knfsd_fh *f, int maxsize) | |
874 | { | |
875 | struct svc_export *exp; | |
876 | struct nameidata nd; | |
877 | struct inode *inode; | |
878 | struct svc_fh fh; | |
879 | int err; | |
880 | ||
881 | err = -EPERM; | |
882 | /* NB: we probably ought to check that it's NUL-terminated */ | |
883 | if (path_lookup(path, 0, &nd)) { | |
884 | printk("nfsd: exp_rootfh path not found %s", path); | |
885 | return err; | |
886 | } | |
887 | inode = nd.dentry->d_inode; | |
888 | ||
889 | dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n", | |
890 | path, nd.dentry, clp->name, | |
891 | inode->i_sb->s_id, inode->i_ino); | |
892 | exp = exp_parent(clp, nd.mnt, nd.dentry, NULL); | |
893 | if (!exp) { | |
894 | dprintk("nfsd: exp_rootfh export not found.\n"); | |
895 | goto out; | |
896 | } | |
897 | ||
898 | /* | |
899 | * fh must be initialized before calling fh_compose | |
900 | */ | |
901 | fh_init(&fh, maxsize); | |
902 | if (fh_compose(&fh, exp, nd.dentry, NULL)) | |
903 | err = -EINVAL; | |
904 | else | |
905 | err = 0; | |
906 | memcpy(f, &fh.fh_handle, sizeof(struct knfsd_fh)); | |
907 | fh_put(&fh); | |
908 | exp_put(exp); | |
909 | out: | |
910 | path_release(&nd); | |
911 | return err; | |
912 | } | |
913 | ||
914 | /* | |
915 | * Called when we need the filehandle for the root of the pseudofs, | |
916 | * for a given NFSv4 client. The root is defined to be the | |
917 | * export point with fsid==0 | |
918 | */ | |
919 | int | |
920 | exp_pseudoroot(struct auth_domain *clp, struct svc_fh *fhp, | |
921 | struct cache_req *creq) | |
922 | { | |
923 | struct svc_expkey *fsid_key; | |
924 | int rv; | |
925 | u32 fsidv[2]; | |
926 | ||
927 | mk_fsid_v1(fsidv, 0); | |
928 | ||
929 | fsid_key = exp_find_key(clp, 1, fsidv, creq); | |
930 | if (IS_ERR(fsid_key) && PTR_ERR(fsid_key) == -EAGAIN) | |
931 | return nfserr_dropit; | |
932 | if (!fsid_key || IS_ERR(fsid_key)) | |
933 | return nfserr_perm; | |
934 | ||
935 | rv = fh_compose(fhp, fsid_key->ek_export, | |
936 | fsid_key->ek_export->ex_dentry, NULL); | |
937 | expkey_put(&fsid_key->h, &svc_expkey_cache); | |
938 | return rv; | |
939 | } | |
940 | ||
941 | /* Iterator */ | |
942 | ||
943 | static void *e_start(struct seq_file *m, loff_t *pos) | |
944 | { | |
945 | loff_t n = *pos; | |
946 | unsigned hash, export; | |
947 | struct cache_head *ch; | |
948 | ||
949 | exp_readlock(); | |
950 | read_lock(&svc_export_cache.hash_lock); | |
951 | if (!n--) | |
952 | return (void *)1; | |
953 | hash = n >> 32; | |
954 | export = n & ((1LL<<32) - 1); | |
955 | ||
956 | ||
957 | for (ch=export_table[hash]; ch; ch=ch->next) | |
958 | if (!export--) | |
959 | return ch; | |
960 | n &= ~((1LL<<32) - 1); | |
961 | do { | |
962 | hash++; | |
963 | n += 1LL<<32; | |
964 | } while(hash < EXPORT_HASHMAX && export_table[hash]==NULL); | |
965 | if (hash >= EXPORT_HASHMAX) | |
966 | return NULL; | |
967 | *pos = n+1; | |
968 | return export_table[hash]; | |
969 | } | |
970 | ||
971 | static void *e_next(struct seq_file *m, void *p, loff_t *pos) | |
972 | { | |
973 | struct cache_head *ch = p; | |
974 | int hash = (*pos >> 32); | |
975 | ||
976 | if (p == (void *)1) | |
977 | hash = 0; | |
978 | else if (ch->next == NULL) { | |
979 | hash++; | |
980 | *pos += 1LL<<32; | |
981 | } else { | |
982 | ++*pos; | |
983 | return ch->next; | |
984 | } | |
985 | *pos &= ~((1LL<<32) - 1); | |
986 | while (hash < EXPORT_HASHMAX && export_table[hash] == NULL) { | |
987 | hash++; | |
988 | *pos += 1LL<<32; | |
989 | } | |
990 | if (hash >= EXPORT_HASHMAX) | |
991 | return NULL; | |
992 | ++*pos; | |
993 | return export_table[hash]; | |
994 | } | |
995 | ||
996 | static void e_stop(struct seq_file *m, void *p) | |
997 | { | |
998 | read_unlock(&svc_export_cache.hash_lock); | |
999 | exp_readunlock(); | |
1000 | } | |
1001 | ||
1002 | static struct flags { | |
1003 | int flag; | |
1004 | char *name[2]; | |
1005 | } expflags[] = { | |
1006 | { NFSEXP_READONLY, {"ro", "rw"}}, | |
1007 | { NFSEXP_INSECURE_PORT, {"insecure", ""}}, | |
1008 | { NFSEXP_ROOTSQUASH, {"root_squash", "no_root_squash"}}, | |
1009 | { NFSEXP_ALLSQUASH, {"all_squash", ""}}, | |
1010 | { NFSEXP_ASYNC, {"async", "sync"}}, | |
1011 | { NFSEXP_GATHERED_WRITES, {"wdelay", "no_wdelay"}}, | |
1012 | { NFSEXP_NOHIDE, {"nohide", ""}}, | |
1013 | { NFSEXP_CROSSMOUNT, {"crossmnt", ""}}, | |
1014 | { NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}}, | |
1015 | { NFSEXP_NOAUTHNLM, {"insecure_locks", ""}}, | |
1016 | #ifdef MSNFS | |
1017 | { NFSEXP_MSNFS, {"msnfs", ""}}, | |
1018 | #endif | |
1019 | { 0, {"", ""}} | |
1020 | }; | |
1021 | ||
1022 | static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong) | |
1023 | { | |
1024 | int first = 0; | |
1025 | struct flags *flg; | |
1026 | ||
1027 | for (flg = expflags; flg->flag; flg++) { | |
1028 | int state = (flg->flag & flag)?0:1; | |
1029 | if (*flg->name[state]) | |
1030 | seq_printf(m, "%s%s", first++?",":"", flg->name[state]); | |
1031 | } | |
1032 | if (flag & NFSEXP_FSID) | |
1033 | seq_printf(m, "%sfsid=%d", first++?",":"", fsid); | |
1034 | if (anonu != (uid_t)-2 && anonu != (0x10000-2)) | |
1035 | seq_printf(m, "%sanonuid=%d", first++?",":"", anonu); | |
1036 | if (anong != (gid_t)-2 && anong != (0x10000-2)) | |
1037 | seq_printf(m, "%sanongid=%d", first++?",":"", anong); | |
1038 | } | |
1039 | ||
1040 | static int e_show(struct seq_file *m, void *p) | |
1041 | { | |
1042 | struct cache_head *cp = p; | |
1043 | struct svc_export *exp = container_of(cp, struct svc_export, h); | |
1044 | svc_client *clp; | |
1045 | ||
1046 | if (p == (void *)1) { | |
1047 | seq_puts(m, "# Version 1.1\n"); | |
1048 | seq_puts(m, "# Path Client(Flags) # IPs\n"); | |
1049 | return 0; | |
1050 | } | |
1051 | ||
1052 | clp = exp->ex_client; | |
1053 | cache_get(&exp->h); | |
1054 | if (cache_check(&svc_export_cache, &exp->h, NULL)) | |
1055 | return 0; | |
1056 | if (cache_put(&exp->h, &svc_export_cache)) BUG(); | |
1057 | return svc_export_show(m, &svc_export_cache, cp); | |
1058 | } | |
1059 | ||
1060 | struct seq_operations nfs_exports_op = { | |
1061 | .start = e_start, | |
1062 | .next = e_next, | |
1063 | .stop = e_stop, | |
1064 | .show = e_show, | |
1065 | }; | |
1066 | ||
1067 | /* | |
1068 | * Add or modify a client. | |
1069 | * Change requests may involve the list of host addresses. The list of | |
1070 | * exports and possibly existing uid maps are left untouched. | |
1071 | */ | |
1072 | int | |
1073 | exp_addclient(struct nfsctl_client *ncp) | |
1074 | { | |
1075 | struct auth_domain *dom; | |
1076 | int i, err; | |
1077 | ||
1078 | /* First, consistency check. */ | |
1079 | err = -EINVAL; | |
1080 | if (! exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX)) | |
1081 | goto out; | |
1082 | if (ncp->cl_naddr > NFSCLNT_ADDRMAX) | |
1083 | goto out; | |
1084 | ||
1085 | /* Lock the hashtable */ | |
1086 | exp_writelock(); | |
1087 | ||
1088 | dom = unix_domain_find(ncp->cl_ident); | |
1089 | ||
1090 | err = -ENOMEM; | |
1091 | if (!dom) | |
1092 | goto out_unlock; | |
1093 | ||
1094 | /* Insert client into hashtable. */ | |
1095 | for (i = 0; i < ncp->cl_naddr; i++) | |
1096 | auth_unix_add_addr(ncp->cl_addrlist[i], dom); | |
1097 | ||
1098 | auth_unix_forget_old(dom); | |
1099 | auth_domain_put(dom); | |
1100 | ||
1101 | err = 0; | |
1102 | ||
1103 | out_unlock: | |
1104 | exp_writeunlock(); | |
1105 | out: | |
1106 | return err; | |
1107 | } | |
1108 | ||
1109 | /* | |
1110 | * Delete a client given an identifier. | |
1111 | */ | |
1112 | int | |
1113 | exp_delclient(struct nfsctl_client *ncp) | |
1114 | { | |
1115 | int err; | |
1116 | struct auth_domain *dom; | |
1117 | ||
1118 | err = -EINVAL; | |
1119 | if (!exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX)) | |
1120 | goto out; | |
1121 | ||
1122 | /* Lock the hashtable */ | |
1123 | exp_writelock(); | |
1124 | ||
1125 | dom = auth_domain_find(ncp->cl_ident); | |
1126 | /* just make sure that no addresses work | |
1127 | * and that it will expire soon | |
1128 | */ | |
1129 | if (dom) { | |
1130 | err = auth_unix_forget_old(dom); | |
1131 | dom->h.expiry_time = get_seconds(); | |
1132 | auth_domain_put(dom); | |
1133 | } | |
1134 | ||
1135 | exp_writeunlock(); | |
1136 | out: | |
1137 | return err; | |
1138 | } | |
1139 | ||
1140 | /* | |
1141 | * Verify that string is non-empty and does not exceed max length. | |
1142 | */ | |
1143 | static int | |
1144 | exp_verify_string(char *cp, int max) | |
1145 | { | |
1146 | int i; | |
1147 | ||
1148 | for (i = 0; i < max; i++) | |
1149 | if (!cp[i]) | |
1150 | return i; | |
1151 | cp[i] = 0; | |
1152 | printk(KERN_NOTICE "nfsd: couldn't validate string %s\n", cp); | |
1153 | return 0; | |
1154 | } | |
1155 | ||
1156 | /* | |
1157 | * Initialize the exports module. | |
1158 | */ | |
1159 | void | |
1160 | nfsd_export_init(void) | |
1161 | { | |
1162 | dprintk("nfsd: initializing export module.\n"); | |
1163 | ||
1164 | cache_register(&svc_export_cache); | |
1165 | cache_register(&svc_expkey_cache); | |
1166 | ||
1167 | } | |
1168 | ||
1169 | /* | |
1170 | * Flush exports table - called when last nfsd thread is killed | |
1171 | */ | |
1172 | void | |
1173 | nfsd_export_flush(void) | |
1174 | { | |
1175 | exp_writelock(); | |
1176 | cache_purge(&svc_expkey_cache); | |
1177 | cache_purge(&svc_export_cache); | |
1178 | exp_writeunlock(); | |
1179 | } | |
1180 | ||
1181 | /* | |
1182 | * Shutdown the exports module. | |
1183 | */ | |
1184 | void | |
1185 | nfsd_export_shutdown(void) | |
1186 | { | |
1187 | ||
1188 | dprintk("nfsd: shutting down export module.\n"); | |
1189 | ||
1190 | exp_writelock(); | |
1191 | ||
1192 | if (cache_unregister(&svc_expkey_cache)) | |
1193 | printk(KERN_ERR "nfsd: failed to unregister expkey cache\n"); | |
1194 | if (cache_unregister(&svc_export_cache)) | |
1195 | printk(KERN_ERR "nfsd: failed to unregister export cache\n"); | |
1196 | svcauth_unix_purge(); | |
1197 | ||
1198 | exp_writeunlock(); | |
1199 | dprintk("nfsd: export shutdown complete.\n"); | |
1200 | } |