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2e4e6a17 HW |
1 | /* |
2 | * x_tables core - Backend for {ip,ip6,arp}_tables | |
3 | * | |
4 | * Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org> | |
5 | * | |
6 | * Based on existing ip_tables code which is | |
7 | * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling | |
8 | * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org> | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License version 2 as | |
12 | * published by the Free Software Foundation. | |
13 | * | |
14 | */ | |
15 | ||
2e4e6a17 HW |
16 | #include <linux/kernel.h> |
17 | #include <linux/socket.h> | |
18 | #include <linux/net.h> | |
19 | #include <linux/proc_fs.h> | |
20 | #include <linux/seq_file.h> | |
21 | #include <linux/string.h> | |
22 | #include <linux/vmalloc.h> | |
9e19bb6d | 23 | #include <linux/mutex.h> |
2e4e6a17 HW |
24 | |
25 | #include <linux/netfilter/x_tables.h> | |
26 | #include <linux/netfilter_arp.h> | |
27 | ||
9e19bb6d | 28 | |
2e4e6a17 HW |
29 | MODULE_LICENSE("GPL"); |
30 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); | |
31 | MODULE_DESCRIPTION("[ip,ip6,arp]_tables backend module"); | |
32 | ||
33 | #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) | |
34 | ||
35 | struct xt_af { | |
9e19bb6d | 36 | struct mutex mutex; |
2e4e6a17 HW |
37 | struct list_head match; |
38 | struct list_head target; | |
39 | struct list_head tables; | |
2722971c | 40 | struct mutex compat_mutex; |
2e4e6a17 HW |
41 | }; |
42 | ||
43 | static struct xt_af *xt; | |
44 | ||
45 | #ifdef DEBUG_IP_FIREWALL_USER | |
46 | #define duprintf(format, args...) printk(format , ## args) | |
47 | #else | |
48 | #define duprintf(format, args...) | |
49 | #endif | |
50 | ||
51 | enum { | |
52 | TABLE, | |
53 | TARGET, | |
54 | MATCH, | |
55 | }; | |
56 | ||
37f9f733 PM |
57 | static const char *xt_prefix[NPROTO] = { |
58 | [AF_INET] = "ip", | |
59 | [AF_INET6] = "ip6", | |
60 | [NF_ARP] = "arp", | |
61 | }; | |
62 | ||
2e4e6a17 HW |
63 | /* Registration hooks for targets. */ |
64 | int | |
a45049c5 | 65 | xt_register_target(struct xt_target *target) |
2e4e6a17 | 66 | { |
a45049c5 | 67 | int ret, af = target->family; |
2e4e6a17 | 68 | |
9e19bb6d | 69 | ret = mutex_lock_interruptible(&xt[af].mutex); |
2e4e6a17 HW |
70 | if (ret != 0) |
71 | return ret; | |
72 | list_add(&target->list, &xt[af].target); | |
9e19bb6d | 73 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
74 | return ret; |
75 | } | |
76 | EXPORT_SYMBOL(xt_register_target); | |
77 | ||
78 | void | |
a45049c5 | 79 | xt_unregister_target(struct xt_target *target) |
2e4e6a17 | 80 | { |
a45049c5 PNA |
81 | int af = target->family; |
82 | ||
9e19bb6d | 83 | mutex_lock(&xt[af].mutex); |
df0933dc | 84 | list_del(&target->list); |
9e19bb6d | 85 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
86 | } |
87 | EXPORT_SYMBOL(xt_unregister_target); | |
88 | ||
52d9c42e PM |
89 | int |
90 | xt_register_targets(struct xt_target *target, unsigned int n) | |
91 | { | |
92 | unsigned int i; | |
93 | int err = 0; | |
94 | ||
95 | for (i = 0; i < n; i++) { | |
96 | err = xt_register_target(&target[i]); | |
97 | if (err) | |
98 | goto err; | |
99 | } | |
100 | return err; | |
101 | ||
102 | err: | |
103 | if (i > 0) | |
104 | xt_unregister_targets(target, i); | |
105 | return err; | |
106 | } | |
107 | EXPORT_SYMBOL(xt_register_targets); | |
108 | ||
109 | void | |
110 | xt_unregister_targets(struct xt_target *target, unsigned int n) | |
111 | { | |
112 | unsigned int i; | |
113 | ||
114 | for (i = 0; i < n; i++) | |
115 | xt_unregister_target(&target[i]); | |
116 | } | |
117 | EXPORT_SYMBOL(xt_unregister_targets); | |
118 | ||
2e4e6a17 | 119 | int |
a45049c5 | 120 | xt_register_match(struct xt_match *match) |
2e4e6a17 | 121 | { |
a45049c5 | 122 | int ret, af = match->family; |
2e4e6a17 | 123 | |
9e19bb6d | 124 | ret = mutex_lock_interruptible(&xt[af].mutex); |
2e4e6a17 HW |
125 | if (ret != 0) |
126 | return ret; | |
127 | ||
128 | list_add(&match->list, &xt[af].match); | |
9e19bb6d | 129 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
130 | |
131 | return ret; | |
132 | } | |
133 | EXPORT_SYMBOL(xt_register_match); | |
134 | ||
135 | void | |
a45049c5 | 136 | xt_unregister_match(struct xt_match *match) |
2e4e6a17 | 137 | { |
a45049c5 PNA |
138 | int af = match->family; |
139 | ||
9e19bb6d | 140 | mutex_lock(&xt[af].mutex); |
df0933dc | 141 | list_del(&match->list); |
9e19bb6d | 142 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
143 | } |
144 | EXPORT_SYMBOL(xt_unregister_match); | |
145 | ||
52d9c42e PM |
146 | int |
147 | xt_register_matches(struct xt_match *match, unsigned int n) | |
148 | { | |
149 | unsigned int i; | |
150 | int err = 0; | |
151 | ||
152 | for (i = 0; i < n; i++) { | |
153 | err = xt_register_match(&match[i]); | |
154 | if (err) | |
155 | goto err; | |
156 | } | |
157 | return err; | |
158 | ||
159 | err: | |
160 | if (i > 0) | |
161 | xt_unregister_matches(match, i); | |
162 | return err; | |
163 | } | |
164 | EXPORT_SYMBOL(xt_register_matches); | |
165 | ||
166 | void | |
167 | xt_unregister_matches(struct xt_match *match, unsigned int n) | |
168 | { | |
169 | unsigned int i; | |
170 | ||
171 | for (i = 0; i < n; i++) | |
172 | xt_unregister_match(&match[i]); | |
173 | } | |
174 | EXPORT_SYMBOL(xt_unregister_matches); | |
175 | ||
2e4e6a17 HW |
176 | |
177 | /* | |
178 | * These are weird, but module loading must not be done with mutex | |
179 | * held (since they will register), and we have to have a single | |
180 | * function to use try_then_request_module(). | |
181 | */ | |
182 | ||
183 | /* Find match, grabs ref. Returns ERR_PTR() on error. */ | |
184 | struct xt_match *xt_find_match(int af, const char *name, u8 revision) | |
185 | { | |
186 | struct xt_match *m; | |
187 | int err = 0; | |
188 | ||
9e19bb6d | 189 | if (mutex_lock_interruptible(&xt[af].mutex) != 0) |
2e4e6a17 HW |
190 | return ERR_PTR(-EINTR); |
191 | ||
192 | list_for_each_entry(m, &xt[af].match, list) { | |
193 | if (strcmp(m->name, name) == 0) { | |
194 | if (m->revision == revision) { | |
195 | if (try_module_get(m->me)) { | |
9e19bb6d | 196 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
197 | return m; |
198 | } | |
199 | } else | |
200 | err = -EPROTOTYPE; /* Found something. */ | |
201 | } | |
202 | } | |
9e19bb6d | 203 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
204 | return ERR_PTR(err); |
205 | } | |
206 | EXPORT_SYMBOL(xt_find_match); | |
207 | ||
208 | /* Find target, grabs ref. Returns ERR_PTR() on error. */ | |
209 | struct xt_target *xt_find_target(int af, const char *name, u8 revision) | |
210 | { | |
211 | struct xt_target *t; | |
212 | int err = 0; | |
213 | ||
9e19bb6d | 214 | if (mutex_lock_interruptible(&xt[af].mutex) != 0) |
2e4e6a17 HW |
215 | return ERR_PTR(-EINTR); |
216 | ||
217 | list_for_each_entry(t, &xt[af].target, list) { | |
218 | if (strcmp(t->name, name) == 0) { | |
219 | if (t->revision == revision) { | |
220 | if (try_module_get(t->me)) { | |
9e19bb6d | 221 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
222 | return t; |
223 | } | |
224 | } else | |
225 | err = -EPROTOTYPE; /* Found something. */ | |
226 | } | |
227 | } | |
9e19bb6d | 228 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
229 | return ERR_PTR(err); |
230 | } | |
231 | EXPORT_SYMBOL(xt_find_target); | |
232 | ||
2e4e6a17 HW |
233 | struct xt_target *xt_request_find_target(int af, const char *name, u8 revision) |
234 | { | |
235 | struct xt_target *target; | |
236 | ||
237 | target = try_then_request_module(xt_find_target(af, name, revision), | |
37f9f733 | 238 | "%st_%s", xt_prefix[af], name); |
2e4e6a17 HW |
239 | if (IS_ERR(target) || !target) |
240 | return NULL; | |
241 | return target; | |
242 | } | |
243 | EXPORT_SYMBOL_GPL(xt_request_find_target); | |
244 | ||
245 | static int match_revfn(int af, const char *name, u8 revision, int *bestp) | |
246 | { | |
247 | struct xt_match *m; | |
248 | int have_rev = 0; | |
249 | ||
250 | list_for_each_entry(m, &xt[af].match, list) { | |
251 | if (strcmp(m->name, name) == 0) { | |
252 | if (m->revision > *bestp) | |
253 | *bestp = m->revision; | |
254 | if (m->revision == revision) | |
255 | have_rev = 1; | |
256 | } | |
257 | } | |
258 | return have_rev; | |
259 | } | |
260 | ||
261 | static int target_revfn(int af, const char *name, u8 revision, int *bestp) | |
262 | { | |
263 | struct xt_target *t; | |
264 | int have_rev = 0; | |
265 | ||
266 | list_for_each_entry(t, &xt[af].target, list) { | |
267 | if (strcmp(t->name, name) == 0) { | |
268 | if (t->revision > *bestp) | |
269 | *bestp = t->revision; | |
270 | if (t->revision == revision) | |
271 | have_rev = 1; | |
272 | } | |
273 | } | |
274 | return have_rev; | |
275 | } | |
276 | ||
277 | /* Returns true or false (if no such extension at all) */ | |
278 | int xt_find_revision(int af, const char *name, u8 revision, int target, | |
279 | int *err) | |
280 | { | |
281 | int have_rev, best = -1; | |
282 | ||
9e19bb6d | 283 | if (mutex_lock_interruptible(&xt[af].mutex) != 0) { |
2e4e6a17 HW |
284 | *err = -EINTR; |
285 | return 1; | |
286 | } | |
287 | if (target == 1) | |
288 | have_rev = target_revfn(af, name, revision, &best); | |
289 | else | |
290 | have_rev = match_revfn(af, name, revision, &best); | |
9e19bb6d | 291 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
292 | |
293 | /* Nothing at all? Return 0 to try loading module. */ | |
294 | if (best == -1) { | |
295 | *err = -ENOENT; | |
296 | return 0; | |
297 | } | |
298 | ||
299 | *err = best; | |
300 | if (!have_rev) | |
301 | *err = -EPROTONOSUPPORT; | |
302 | return 1; | |
303 | } | |
304 | EXPORT_SYMBOL_GPL(xt_find_revision); | |
305 | ||
37f9f733 PM |
306 | int xt_check_match(const struct xt_match *match, unsigned short family, |
307 | unsigned int size, const char *table, unsigned int hook_mask, | |
308 | unsigned short proto, int inv_proto) | |
309 | { | |
310 | if (XT_ALIGN(match->matchsize) != size) { | |
311 | printk("%s_tables: %s match: invalid size %Zu != %u\n", | |
312 | xt_prefix[family], match->name, | |
313 | XT_ALIGN(match->matchsize), size); | |
314 | return -EINVAL; | |
315 | } | |
316 | if (match->table && strcmp(match->table, table)) { | |
317 | printk("%s_tables: %s match: only valid in %s table, not %s\n", | |
318 | xt_prefix[family], match->name, match->table, table); | |
319 | return -EINVAL; | |
320 | } | |
321 | if (match->hooks && (hook_mask & ~match->hooks) != 0) { | |
322 | printk("%s_tables: %s match: bad hook_mask %u\n", | |
323 | xt_prefix[family], match->name, hook_mask); | |
324 | return -EINVAL; | |
325 | } | |
326 | if (match->proto && (match->proto != proto || inv_proto)) { | |
327 | printk("%s_tables: %s match: only valid for protocol %u\n", | |
328 | xt_prefix[family], match->name, match->proto); | |
329 | return -EINVAL; | |
330 | } | |
331 | return 0; | |
332 | } | |
333 | EXPORT_SYMBOL_GPL(xt_check_match); | |
334 | ||
2722971c | 335 | #ifdef CONFIG_COMPAT |
9fa492cd | 336 | int xt_compat_match_offset(struct xt_match *match) |
2722971c | 337 | { |
9fa492cd PM |
338 | u_int16_t csize = match->compatsize ? : match->matchsize; |
339 | return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize); | |
340 | } | |
341 | EXPORT_SYMBOL_GPL(xt_compat_match_offset); | |
342 | ||
343 | void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr, | |
344 | int *size) | |
345 | { | |
346 | struct xt_match *match = m->u.kernel.match; | |
347 | struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m; | |
348 | int pad, off = xt_compat_match_offset(match); | |
349 | u_int16_t msize = cm->u.user.match_size; | |
350 | ||
351 | m = *dstptr; | |
352 | memcpy(m, cm, sizeof(*cm)); | |
353 | if (match->compat_from_user) | |
354 | match->compat_from_user(m->data, cm->data); | |
355 | else | |
356 | memcpy(m->data, cm->data, msize - sizeof(*cm)); | |
357 | pad = XT_ALIGN(match->matchsize) - match->matchsize; | |
358 | if (pad > 0) | |
359 | memset(m->data + match->matchsize, 0, pad); | |
360 | ||
361 | msize += off; | |
362 | m->u.user.match_size = msize; | |
363 | ||
364 | *size += off; | |
365 | *dstptr += msize; | |
366 | } | |
367 | EXPORT_SYMBOL_GPL(xt_compat_match_from_user); | |
368 | ||
369 | int xt_compat_match_to_user(struct xt_entry_match *m, void __user **dstptr, | |
370 | int *size) | |
371 | { | |
372 | struct xt_match *match = m->u.kernel.match; | |
373 | struct compat_xt_entry_match __user *cm = *dstptr; | |
374 | int off = xt_compat_match_offset(match); | |
375 | u_int16_t msize = m->u.user.match_size - off; | |
376 | ||
377 | if (copy_to_user(cm, m, sizeof(*cm)) || | |
378 | put_user(msize, &cm->u.user.match_size)) | |
379 | return -EFAULT; | |
380 | ||
381 | if (match->compat_to_user) { | |
382 | if (match->compat_to_user((void __user *)cm->data, m->data)) | |
383 | return -EFAULT; | |
384 | } else { | |
385 | if (copy_to_user(cm->data, m->data, msize - sizeof(*cm))) | |
386 | return -EFAULT; | |
2722971c | 387 | } |
9fa492cd PM |
388 | |
389 | *size -= off; | |
390 | *dstptr += msize; | |
391 | return 0; | |
2722971c | 392 | } |
9fa492cd PM |
393 | EXPORT_SYMBOL_GPL(xt_compat_match_to_user); |
394 | #endif /* CONFIG_COMPAT */ | |
2722971c | 395 | |
37f9f733 PM |
396 | int xt_check_target(const struct xt_target *target, unsigned short family, |
397 | unsigned int size, const char *table, unsigned int hook_mask, | |
398 | unsigned short proto, int inv_proto) | |
399 | { | |
400 | if (XT_ALIGN(target->targetsize) != size) { | |
401 | printk("%s_tables: %s target: invalid size %Zu != %u\n", | |
402 | xt_prefix[family], target->name, | |
403 | XT_ALIGN(target->targetsize), size); | |
404 | return -EINVAL; | |
405 | } | |
406 | if (target->table && strcmp(target->table, table)) { | |
407 | printk("%s_tables: %s target: only valid in %s table, not %s\n", | |
408 | xt_prefix[family], target->name, target->table, table); | |
409 | return -EINVAL; | |
410 | } | |
411 | if (target->hooks && (hook_mask & ~target->hooks) != 0) { | |
412 | printk("%s_tables: %s target: bad hook_mask %u\n", | |
413 | xt_prefix[family], target->name, hook_mask); | |
414 | return -EINVAL; | |
415 | } | |
416 | if (target->proto && (target->proto != proto || inv_proto)) { | |
417 | printk("%s_tables: %s target: only valid for protocol %u\n", | |
418 | xt_prefix[family], target->name, target->proto); | |
419 | return -EINVAL; | |
420 | } | |
421 | return 0; | |
422 | } | |
423 | EXPORT_SYMBOL_GPL(xt_check_target); | |
424 | ||
2722971c | 425 | #ifdef CONFIG_COMPAT |
9fa492cd | 426 | int xt_compat_target_offset(struct xt_target *target) |
2722971c | 427 | { |
9fa492cd PM |
428 | u_int16_t csize = target->compatsize ? : target->targetsize; |
429 | return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize); | |
430 | } | |
431 | EXPORT_SYMBOL_GPL(xt_compat_target_offset); | |
432 | ||
433 | void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr, | |
434 | int *size) | |
435 | { | |
436 | struct xt_target *target = t->u.kernel.target; | |
437 | struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t; | |
438 | int pad, off = xt_compat_target_offset(target); | |
439 | u_int16_t tsize = ct->u.user.target_size; | |
440 | ||
441 | t = *dstptr; | |
442 | memcpy(t, ct, sizeof(*ct)); | |
443 | if (target->compat_from_user) | |
444 | target->compat_from_user(t->data, ct->data); | |
445 | else | |
446 | memcpy(t->data, ct->data, tsize - sizeof(*ct)); | |
447 | pad = XT_ALIGN(target->targetsize) - target->targetsize; | |
448 | if (pad > 0) | |
449 | memset(t->data + target->targetsize, 0, pad); | |
450 | ||
451 | tsize += off; | |
452 | t->u.user.target_size = tsize; | |
453 | ||
454 | *size += off; | |
455 | *dstptr += tsize; | |
456 | } | |
457 | EXPORT_SYMBOL_GPL(xt_compat_target_from_user); | |
458 | ||
459 | int xt_compat_target_to_user(struct xt_entry_target *t, void __user **dstptr, | |
460 | int *size) | |
461 | { | |
462 | struct xt_target *target = t->u.kernel.target; | |
463 | struct compat_xt_entry_target __user *ct = *dstptr; | |
464 | int off = xt_compat_target_offset(target); | |
465 | u_int16_t tsize = t->u.user.target_size - off; | |
466 | ||
467 | if (copy_to_user(ct, t, sizeof(*ct)) || | |
468 | put_user(tsize, &ct->u.user.target_size)) | |
469 | return -EFAULT; | |
470 | ||
471 | if (target->compat_to_user) { | |
472 | if (target->compat_to_user((void __user *)ct->data, t->data)) | |
473 | return -EFAULT; | |
474 | } else { | |
475 | if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct))) | |
476 | return -EFAULT; | |
2722971c | 477 | } |
9fa492cd PM |
478 | |
479 | *size -= off; | |
480 | *dstptr += tsize; | |
481 | return 0; | |
2722971c | 482 | } |
9fa492cd | 483 | EXPORT_SYMBOL_GPL(xt_compat_target_to_user); |
2722971c DM |
484 | #endif |
485 | ||
2e4e6a17 HW |
486 | struct xt_table_info *xt_alloc_table_info(unsigned int size) |
487 | { | |
488 | struct xt_table_info *newinfo; | |
489 | int cpu; | |
490 | ||
491 | /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ | |
492 | if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > num_physpages) | |
493 | return NULL; | |
494 | ||
495 | newinfo = kzalloc(sizeof(struct xt_table_info), GFP_KERNEL); | |
496 | if (!newinfo) | |
497 | return NULL; | |
498 | ||
499 | newinfo->size = size; | |
500 | ||
6f912042 | 501 | for_each_possible_cpu(cpu) { |
2e4e6a17 HW |
502 | if (size <= PAGE_SIZE) |
503 | newinfo->entries[cpu] = kmalloc_node(size, | |
504 | GFP_KERNEL, | |
505 | cpu_to_node(cpu)); | |
506 | else | |
507 | newinfo->entries[cpu] = vmalloc_node(size, | |
508 | cpu_to_node(cpu)); | |
509 | ||
510 | if (newinfo->entries[cpu] == NULL) { | |
511 | xt_free_table_info(newinfo); | |
512 | return NULL; | |
513 | } | |
514 | } | |
515 | ||
516 | return newinfo; | |
517 | } | |
518 | EXPORT_SYMBOL(xt_alloc_table_info); | |
519 | ||
520 | void xt_free_table_info(struct xt_table_info *info) | |
521 | { | |
522 | int cpu; | |
523 | ||
6f912042 | 524 | for_each_possible_cpu(cpu) { |
2e4e6a17 HW |
525 | if (info->size <= PAGE_SIZE) |
526 | kfree(info->entries[cpu]); | |
527 | else | |
528 | vfree(info->entries[cpu]); | |
529 | } | |
530 | kfree(info); | |
531 | } | |
532 | EXPORT_SYMBOL(xt_free_table_info); | |
533 | ||
534 | /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ | |
535 | struct xt_table *xt_find_table_lock(int af, const char *name) | |
536 | { | |
537 | struct xt_table *t; | |
538 | ||
9e19bb6d | 539 | if (mutex_lock_interruptible(&xt[af].mutex) != 0) |
2e4e6a17 HW |
540 | return ERR_PTR(-EINTR); |
541 | ||
542 | list_for_each_entry(t, &xt[af].tables, list) | |
543 | if (strcmp(t->name, name) == 0 && try_module_get(t->me)) | |
544 | return t; | |
9e19bb6d | 545 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
546 | return NULL; |
547 | } | |
548 | EXPORT_SYMBOL_GPL(xt_find_table_lock); | |
549 | ||
550 | void xt_table_unlock(struct xt_table *table) | |
551 | { | |
9e19bb6d | 552 | mutex_unlock(&xt[table->af].mutex); |
2e4e6a17 HW |
553 | } |
554 | EXPORT_SYMBOL_GPL(xt_table_unlock); | |
555 | ||
2722971c DM |
556 | #ifdef CONFIG_COMPAT |
557 | void xt_compat_lock(int af) | |
558 | { | |
559 | mutex_lock(&xt[af].compat_mutex); | |
560 | } | |
561 | EXPORT_SYMBOL_GPL(xt_compat_lock); | |
562 | ||
563 | void xt_compat_unlock(int af) | |
564 | { | |
565 | mutex_unlock(&xt[af].compat_mutex); | |
566 | } | |
567 | EXPORT_SYMBOL_GPL(xt_compat_unlock); | |
568 | #endif | |
2e4e6a17 HW |
569 | |
570 | struct xt_table_info * | |
571 | xt_replace_table(struct xt_table *table, | |
572 | unsigned int num_counters, | |
573 | struct xt_table_info *newinfo, | |
574 | int *error) | |
575 | { | |
576 | struct xt_table_info *oldinfo, *private; | |
577 | ||
578 | /* Do the substitution. */ | |
579 | write_lock_bh(&table->lock); | |
580 | private = table->private; | |
581 | /* Check inside lock: is the old number correct? */ | |
582 | if (num_counters != private->number) { | |
583 | duprintf("num_counters != table->private->number (%u/%u)\n", | |
584 | num_counters, private->number); | |
585 | write_unlock_bh(&table->lock); | |
586 | *error = -EAGAIN; | |
587 | return NULL; | |
588 | } | |
589 | oldinfo = private; | |
590 | table->private = newinfo; | |
591 | newinfo->initial_entries = oldinfo->initial_entries; | |
592 | write_unlock_bh(&table->lock); | |
593 | ||
594 | return oldinfo; | |
595 | } | |
596 | EXPORT_SYMBOL_GPL(xt_replace_table); | |
597 | ||
598 | int xt_register_table(struct xt_table *table, | |
599 | struct xt_table_info *bootstrap, | |
600 | struct xt_table_info *newinfo) | |
601 | { | |
602 | int ret; | |
603 | struct xt_table_info *private; | |
df0933dc | 604 | struct xt_table *t; |
2e4e6a17 | 605 | |
9e19bb6d | 606 | ret = mutex_lock_interruptible(&xt[table->af].mutex); |
2e4e6a17 HW |
607 | if (ret != 0) |
608 | return ret; | |
609 | ||
610 | /* Don't autoload: we'd eat our tail... */ | |
df0933dc PM |
611 | list_for_each_entry(t, &xt[table->af].tables, list) { |
612 | if (strcmp(t->name, table->name) == 0) { | |
613 | ret = -EEXIST; | |
614 | goto unlock; | |
615 | } | |
2e4e6a17 HW |
616 | } |
617 | ||
618 | /* Simplifies replace_table code. */ | |
619 | table->private = bootstrap; | |
91536b7a | 620 | rwlock_init(&table->lock); |
2e4e6a17 HW |
621 | if (!xt_replace_table(table, 0, newinfo, &ret)) |
622 | goto unlock; | |
623 | ||
624 | private = table->private; | |
625 | duprintf("table->private->number = %u\n", private->number); | |
626 | ||
627 | /* save number of initial entries */ | |
628 | private->initial_entries = private->number; | |
629 | ||
df0933dc | 630 | list_add(&table->list, &xt[table->af].tables); |
2e4e6a17 HW |
631 | |
632 | ret = 0; | |
633 | unlock: | |
9e19bb6d | 634 | mutex_unlock(&xt[table->af].mutex); |
2e4e6a17 HW |
635 | return ret; |
636 | } | |
637 | EXPORT_SYMBOL_GPL(xt_register_table); | |
638 | ||
639 | void *xt_unregister_table(struct xt_table *table) | |
640 | { | |
641 | struct xt_table_info *private; | |
642 | ||
9e19bb6d | 643 | mutex_lock(&xt[table->af].mutex); |
2e4e6a17 | 644 | private = table->private; |
df0933dc | 645 | list_del(&table->list); |
9e19bb6d | 646 | mutex_unlock(&xt[table->af].mutex); |
2e4e6a17 HW |
647 | |
648 | return private; | |
649 | } | |
650 | EXPORT_SYMBOL_GPL(xt_unregister_table); | |
651 | ||
652 | #ifdef CONFIG_PROC_FS | |
653 | static char *xt_proto_prefix[NPROTO] = { | |
654 | [AF_INET] = "ip", | |
655 | [AF_INET6] = "ip6", | |
656 | [NF_ARP] = "arp", | |
657 | }; | |
658 | ||
659 | static struct list_head *xt_get_idx(struct list_head *list, struct seq_file *seq, loff_t pos) | |
660 | { | |
661 | struct list_head *head = list->next; | |
662 | ||
663 | if (!head || list_empty(list)) | |
664 | return NULL; | |
665 | ||
666 | while (pos && (head = head->next)) { | |
667 | if (head == list) | |
668 | return NULL; | |
669 | pos--; | |
670 | } | |
671 | return pos ? NULL : head; | |
672 | } | |
673 | ||
674 | static struct list_head *type2list(u_int16_t af, u_int16_t type) | |
675 | { | |
676 | struct list_head *list; | |
677 | ||
678 | switch (type) { | |
679 | case TARGET: | |
680 | list = &xt[af].target; | |
681 | break; | |
682 | case MATCH: | |
683 | list = &xt[af].match; | |
684 | break; | |
685 | case TABLE: | |
686 | list = &xt[af].tables; | |
687 | break; | |
688 | default: | |
689 | list = NULL; | |
690 | break; | |
691 | } | |
692 | ||
693 | return list; | |
694 | } | |
695 | ||
696 | static void *xt_tgt_seq_start(struct seq_file *seq, loff_t *pos) | |
697 | { | |
698 | struct proc_dir_entry *pde = (struct proc_dir_entry *) seq->private; | |
699 | u_int16_t af = (unsigned long)pde->data & 0xffff; | |
700 | u_int16_t type = (unsigned long)pde->data >> 16; | |
701 | struct list_head *list; | |
702 | ||
703 | if (af >= NPROTO) | |
704 | return NULL; | |
705 | ||
706 | list = type2list(af, type); | |
707 | if (!list) | |
708 | return NULL; | |
709 | ||
9e19bb6d | 710 | if (mutex_lock_interruptible(&xt[af].mutex) != 0) |
2e4e6a17 HW |
711 | return NULL; |
712 | ||
713 | return xt_get_idx(list, seq, *pos); | |
714 | } | |
715 | ||
716 | static void *xt_tgt_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
717 | { | |
718 | struct proc_dir_entry *pde = seq->private; | |
719 | u_int16_t af = (unsigned long)pde->data & 0xffff; | |
720 | u_int16_t type = (unsigned long)pde->data >> 16; | |
721 | struct list_head *list; | |
722 | ||
723 | if (af >= NPROTO) | |
724 | return NULL; | |
725 | ||
726 | list = type2list(af, type); | |
727 | if (!list) | |
728 | return NULL; | |
729 | ||
730 | (*pos)++; | |
731 | return xt_get_idx(list, seq, *pos); | |
732 | } | |
733 | ||
734 | static void xt_tgt_seq_stop(struct seq_file *seq, void *v) | |
735 | { | |
736 | struct proc_dir_entry *pde = seq->private; | |
737 | u_int16_t af = (unsigned long)pde->data & 0xffff; | |
738 | ||
9e19bb6d | 739 | mutex_unlock(&xt[af].mutex); |
2e4e6a17 HW |
740 | } |
741 | ||
742 | static int xt_name_seq_show(struct seq_file *seq, void *v) | |
743 | { | |
744 | char *name = (char *)v + sizeof(struct list_head); | |
745 | ||
746 | if (strlen(name)) | |
747 | return seq_printf(seq, "%s\n", name); | |
748 | else | |
749 | return 0; | |
750 | } | |
751 | ||
752 | static struct seq_operations xt_tgt_seq_ops = { | |
753 | .start = xt_tgt_seq_start, | |
754 | .next = xt_tgt_seq_next, | |
755 | .stop = xt_tgt_seq_stop, | |
756 | .show = xt_name_seq_show, | |
757 | }; | |
758 | ||
759 | static int xt_tgt_open(struct inode *inode, struct file *file) | |
760 | { | |
761 | int ret; | |
762 | ||
763 | ret = seq_open(file, &xt_tgt_seq_ops); | |
764 | if (!ret) { | |
765 | struct seq_file *seq = file->private_data; | |
766 | struct proc_dir_entry *pde = PDE(inode); | |
767 | ||
768 | seq->private = pde; | |
769 | } | |
770 | ||
771 | return ret; | |
772 | } | |
773 | ||
774 | static struct file_operations xt_file_ops = { | |
775 | .owner = THIS_MODULE, | |
776 | .open = xt_tgt_open, | |
777 | .read = seq_read, | |
778 | .llseek = seq_lseek, | |
779 | .release = seq_release, | |
780 | }; | |
781 | ||
782 | #define FORMAT_TABLES "_tables_names" | |
783 | #define FORMAT_MATCHES "_tables_matches" | |
784 | #define FORMAT_TARGETS "_tables_targets" | |
785 | ||
786 | #endif /* CONFIG_PROC_FS */ | |
787 | ||
788 | int xt_proto_init(int af) | |
789 | { | |
790 | #ifdef CONFIG_PROC_FS | |
791 | char buf[XT_FUNCTION_MAXNAMELEN]; | |
792 | struct proc_dir_entry *proc; | |
793 | #endif | |
794 | ||
795 | if (af >= NPROTO) | |
796 | return -EINVAL; | |
797 | ||
798 | ||
799 | #ifdef CONFIG_PROC_FS | |
800 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
801 | strlcat(buf, FORMAT_TABLES, sizeof(buf)); | |
802 | proc = proc_net_fops_create(buf, 0440, &xt_file_ops); | |
803 | if (!proc) | |
804 | goto out; | |
805 | proc->data = (void *) ((unsigned long) af | (TABLE << 16)); | |
806 | ||
807 | ||
808 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
809 | strlcat(buf, FORMAT_MATCHES, sizeof(buf)); | |
810 | proc = proc_net_fops_create(buf, 0440, &xt_file_ops); | |
811 | if (!proc) | |
812 | goto out_remove_tables; | |
813 | proc->data = (void *) ((unsigned long) af | (MATCH << 16)); | |
814 | ||
815 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
816 | strlcat(buf, FORMAT_TARGETS, sizeof(buf)); | |
817 | proc = proc_net_fops_create(buf, 0440, &xt_file_ops); | |
818 | if (!proc) | |
819 | goto out_remove_matches; | |
820 | proc->data = (void *) ((unsigned long) af | (TARGET << 16)); | |
821 | #endif | |
822 | ||
823 | return 0; | |
824 | ||
825 | #ifdef CONFIG_PROC_FS | |
826 | out_remove_matches: | |
827 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
828 | strlcat(buf, FORMAT_MATCHES, sizeof(buf)); | |
829 | proc_net_remove(buf); | |
830 | ||
831 | out_remove_tables: | |
832 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
833 | strlcat(buf, FORMAT_TABLES, sizeof(buf)); | |
834 | proc_net_remove(buf); | |
835 | out: | |
836 | return -1; | |
837 | #endif | |
838 | } | |
839 | EXPORT_SYMBOL_GPL(xt_proto_init); | |
840 | ||
841 | void xt_proto_fini(int af) | |
842 | { | |
843 | #ifdef CONFIG_PROC_FS | |
844 | char buf[XT_FUNCTION_MAXNAMELEN]; | |
845 | ||
846 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
847 | strlcat(buf, FORMAT_TABLES, sizeof(buf)); | |
848 | proc_net_remove(buf); | |
849 | ||
850 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
851 | strlcat(buf, FORMAT_TARGETS, sizeof(buf)); | |
852 | proc_net_remove(buf); | |
853 | ||
854 | strlcpy(buf, xt_proto_prefix[af], sizeof(buf)); | |
855 | strlcat(buf, FORMAT_MATCHES, sizeof(buf)); | |
856 | proc_net_remove(buf); | |
857 | #endif /*CONFIG_PROC_FS*/ | |
858 | } | |
859 | EXPORT_SYMBOL_GPL(xt_proto_fini); | |
860 | ||
861 | ||
862 | static int __init xt_init(void) | |
863 | { | |
864 | int i; | |
865 | ||
866 | xt = kmalloc(sizeof(struct xt_af) * NPROTO, GFP_KERNEL); | |
867 | if (!xt) | |
868 | return -ENOMEM; | |
869 | ||
870 | for (i = 0; i < NPROTO; i++) { | |
9e19bb6d | 871 | mutex_init(&xt[i].mutex); |
2722971c DM |
872 | #ifdef CONFIG_COMPAT |
873 | mutex_init(&xt[i].compat_mutex); | |
874 | #endif | |
2e4e6a17 HW |
875 | INIT_LIST_HEAD(&xt[i].target); |
876 | INIT_LIST_HEAD(&xt[i].match); | |
877 | INIT_LIST_HEAD(&xt[i].tables); | |
878 | } | |
879 | return 0; | |
880 | } | |
881 | ||
882 | static void __exit xt_fini(void) | |
883 | { | |
884 | kfree(xt); | |
885 | } | |
886 | ||
887 | module_init(xt_init); | |
888 | module_exit(xt_fini); | |
889 |