Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * ebtables | |
3 | * | |
4 | * Author: | |
5 | * Bart De Schuymer <bdschuym@pandora.be> | |
6 | * | |
7 | * ebtables.c,v 2.0, July, 2002 | |
8 | * | |
069d4a7b | 9 | * This code is strongly inspired by the iptables code which is |
1da177e4 LT |
10 | * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | */ | |
ff67e4e4 | 17 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
1da177e4 LT |
18 | #include <linux/kmod.h> |
19 | #include <linux/module.h> | |
20 | #include <linux/vmalloc.h> | |
18219d3f | 21 | #include <linux/netfilter/x_tables.h> |
1da177e4 LT |
22 | #include <linux/netfilter_bridge/ebtables.h> |
23 | #include <linux/spinlock.h> | |
df0933dc | 24 | #include <linux/mutex.h> |
5a0e3ad6 | 25 | #include <linux/slab.h> |
1da177e4 LT |
26 | #include <asm/uaccess.h> |
27 | #include <linux/smp.h> | |
c8923c6b | 28 | #include <linux/cpumask.h> |
c55fbbb4 | 29 | #include <linux/audit.h> |
1da177e4 LT |
30 | #include <net/sock.h> |
31 | /* needed for logical [in,out]-dev filtering */ | |
32 | #include "../br_private.h" | |
33 | ||
1da177e4 | 34 | #define BUGPRINT(format, args...) printk("kernel msg: ebtables bug: please "\ |
9d6f229f | 35 | "report to author: "format, ## args) |
1da177e4 | 36 | /* #define BUGPRINT(format, args...) */ |
1da177e4 | 37 | |
7f495ad9 | 38 | /* Each cpu has its own set of counters, so there is no need for write_lock in |
1da177e4 LT |
39 | * the softirq |
40 | * For reading or updating the counters, the user context needs to | |
41 | * get a write_lock | |
42 | */ | |
43 | ||
44 | /* The size of each set of counters is altered to get cache alignment */ | |
45 | #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) | |
46 | #define COUNTER_OFFSET(n) (SMP_ALIGN(n * sizeof(struct ebt_counter))) | |
47 | #define COUNTER_BASE(c, n, cpu) ((struct ebt_counter *)(((char *)c) + \ | |
052a4bc4 | 48 | COUNTER_OFFSET(n) * cpu)) |
1da177e4 LT |
49 | |
50 | ||
51 | ||
57b47a53 | 52 | static DEFINE_MUTEX(ebt_mutex); |
1da177e4 | 53 | |
81e675c2 FW |
54 | #ifdef CONFIG_COMPAT |
55 | static void ebt_standard_compat_from_user(void *dst, const void *src) | |
56 | { | |
57 | int v = *(compat_int_t *)src; | |
58 | ||
59 | if (v >= 0) | |
60 | v += xt_compat_calc_jump(NFPROTO_BRIDGE, v); | |
61 | memcpy(dst, &v, sizeof(v)); | |
62 | } | |
63 | ||
64 | static int ebt_standard_compat_to_user(void __user *dst, const void *src) | |
65 | { | |
66 | compat_int_t cv = *(int *)src; | |
67 | ||
68 | if (cv >= 0) | |
69 | cv -= xt_compat_calc_jump(NFPROTO_BRIDGE, cv); | |
70 | return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0; | |
71 | } | |
72 | #endif | |
73 | ||
74 | ||
043ef46c | 75 | static struct xt_target ebt_standard_target = { |
001a18d3 JE |
76 | .name = "standard", |
77 | .revision = 0, | |
78 | .family = NFPROTO_BRIDGE, | |
043ef46c | 79 | .targetsize = sizeof(int), |
81e675c2 FW |
80 | #ifdef CONFIG_COMPAT |
81 | .compatsize = sizeof(compat_int_t), | |
82 | .compat_from_user = ebt_standard_compat_from_user, | |
83 | .compat_to_user = ebt_standard_compat_to_user, | |
84 | #endif | |
18219d3f | 85 | }; |
1da177e4 | 86 | |
7eb35586 JE |
87 | static inline int |
88 | ebt_do_watcher(const struct ebt_entry_watcher *w, struct sk_buff *skb, | |
de74c169 | 89 | struct xt_action_param *par) |
1da177e4 | 90 | { |
7eb35586 JE |
91 | par->target = w->u.watcher; |
92 | par->targinfo = w->data; | |
93 | w->u.watcher->target(skb, par); | |
1da177e4 LT |
94 | /* watchers don't give a verdict */ |
95 | return 0; | |
96 | } | |
97 | ||
de74c169 JE |
98 | static inline int |
99 | ebt_do_match(struct ebt_entry_match *m, const struct sk_buff *skb, | |
100 | struct xt_action_param *par) | |
1da177e4 | 101 | { |
f7108a20 JE |
102 | par->match = m->u.match; |
103 | par->matchinfo = m->data; | |
d61ba9fd | 104 | return m->u.match->match(skb, par) ? EBT_MATCH : EBT_NOMATCH; |
1da177e4 LT |
105 | } |
106 | ||
d5d1baa1 JE |
107 | static inline int |
108 | ebt_dev_check(const char *entry, const struct net_device *device) | |
1da177e4 LT |
109 | { |
110 | int i = 0; | |
f3d8b2e4 | 111 | const char *devname; |
1da177e4 LT |
112 | |
113 | if (*entry == '\0') | |
114 | return 0; | |
115 | if (!device) | |
116 | return 1; | |
f3d8b2e4 | 117 | devname = device->name; |
1da177e4 LT |
118 | /* 1 is the wildcard token */ |
119 | while (entry[i] != '\0' && entry[i] != 1 && entry[i] == devname[i]) | |
120 | i++; | |
a97bfc1d | 121 | return devname[i] != entry[i] && entry[i] != 1; |
1da177e4 LT |
122 | } |
123 | ||
31a5b837 | 124 | #define FWINV2(bool, invflg) ((bool) ^ !!(e->invflags & invflg)) |
1da177e4 | 125 | /* process standard matches */ |
d5d1baa1 | 126 | static inline int |
13937911 | 127 | ebt_basic_match(const struct ebt_entry *e, const struct sk_buff *skb, |
052a4bc4 | 128 | const struct net_device *in, const struct net_device *out) |
1da177e4 | 129 | { |
13937911 | 130 | const struct ethhdr *h = eth_hdr(skb); |
b5ed54e9 | 131 | const struct net_bridge_port *p; |
13937911 | 132 | __be16 ethproto; |
1da177e4 | 133 | |
df8a39de | 134 | if (skb_vlan_tag_present(skb)) |
13937911 JG |
135 | ethproto = htons(ETH_P_8021Q); |
136 | else | |
137 | ethproto = h->h_proto; | |
138 | ||
1da177e4 | 139 | if (e->bitmask & EBT_802_3) { |
27cf6a6e | 140 | if (FWINV2(eth_proto_is_802_3(ethproto), EBT_IPROTO)) |
1da177e4 LT |
141 | return 1; |
142 | } else if (!(e->bitmask & EBT_NOPROTO) && | |
13937911 | 143 | FWINV2(e->ethproto != ethproto, EBT_IPROTO)) |
1da177e4 LT |
144 | return 1; |
145 | ||
146 | if (FWINV2(ebt_dev_check(e->in, in), EBT_IIN)) | |
147 | return 1; | |
148 | if (FWINV2(ebt_dev_check(e->out, out), EBT_IOUT)) | |
149 | return 1; | |
f350a0a8 | 150 | /* rcu_read_lock()ed by nf_hook_slow */ |
b5ed54e9 | 151 | if (in && (p = br_port_get_rcu(in)) != NULL && |
152 | FWINV2(ebt_dev_check(e->logical_in, p->br->dev), EBT_ILOGICALIN)) | |
1da177e4 | 153 | return 1; |
b5ed54e9 | 154 | if (out && (p = br_port_get_rcu(out)) != NULL && |
155 | FWINV2(ebt_dev_check(e->logical_out, p->br->dev), EBT_ILOGICALOUT)) | |
1da177e4 LT |
156 | return 1; |
157 | ||
158 | if (e->bitmask & EBT_SOURCEMAC) { | |
4ae89ad9 JP |
159 | if (FWINV2(!ether_addr_equal_masked(h->h_source, |
160 | e->sourcemac, e->sourcemsk), | |
161 | EBT_ISOURCE)) | |
1da177e4 LT |
162 | return 1; |
163 | } | |
164 | if (e->bitmask & EBT_DESTMAC) { | |
4ae89ad9 JP |
165 | if (FWINV2(!ether_addr_equal_masked(h->h_dest, |
166 | e->destmac, e->destmsk), | |
167 | EBT_IDEST)) | |
1da177e4 LT |
168 | return 1; |
169 | } | |
170 | return 0; | |
171 | } | |
172 | ||
851345c5 | 173 | static inline |
98e86403 JE |
174 | struct ebt_entry *ebt_next_entry(const struct ebt_entry *entry) |
175 | { | |
176 | return (void *)entry + entry->next_offset; | |
177 | } | |
178 | ||
1da177e4 | 179 | /* Do some firewalling */ |
97b59c3a EB |
180 | unsigned int ebt_do_table(struct sk_buff *skb, |
181 | const struct nf_hook_state *state, | |
182 | struct ebt_table *table) | |
1da177e4 | 183 | { |
97b59c3a | 184 | unsigned int hook = state->hook; |
1da177e4 LT |
185 | int i, nentries; |
186 | struct ebt_entry *point; | |
187 | struct ebt_counter *counter_base, *cb_base; | |
d5d1baa1 | 188 | const struct ebt_entry_target *t; |
1da177e4 LT |
189 | int verdict, sp = 0; |
190 | struct ebt_chainstack *cs; | |
191 | struct ebt_entries *chaininfo; | |
d5d1baa1 JE |
192 | const char *base; |
193 | const struct ebt_table_info *private; | |
de74c169 | 194 | struct xt_action_param acpar; |
f7108a20 | 195 | |
de74c169 | 196 | acpar.family = NFPROTO_BRIDGE; |
156c196f | 197 | acpar.net = state->net; |
97b59c3a EB |
198 | acpar.in = state->in; |
199 | acpar.out = state->out; | |
b4ba2611 | 200 | acpar.hotdrop = false; |
de74c169 | 201 | acpar.hooknum = hook; |
1da177e4 LT |
202 | |
203 | read_lock_bh(&table->lock); | |
204 | private = table->private; | |
205 | cb_base = COUNTER_BASE(private->counters, private->nentries, | |
206 | smp_processor_id()); | |
207 | if (private->chainstack) | |
208 | cs = private->chainstack[smp_processor_id()]; | |
209 | else | |
210 | cs = NULL; | |
211 | chaininfo = private->hook_entry[hook]; | |
212 | nentries = private->hook_entry[hook]->nentries; | |
213 | point = (struct ebt_entry *)(private->hook_entry[hook]->data); | |
214 | counter_base = cb_base + private->hook_entry[hook]->counter_offset; | |
215 | /* base for chain jumps */ | |
216 | base = private->entries; | |
217 | i = 0; | |
218 | while (i < nentries) { | |
97b59c3a | 219 | if (ebt_basic_match(point, skb, state->in, state->out)) |
1da177e4 LT |
220 | goto letscontinue; |
221 | ||
de74c169 | 222 | if (EBT_MATCH_ITERATE(point, ebt_do_match, skb, &acpar) != 0) |
1da177e4 | 223 | goto letscontinue; |
b4ba2611 | 224 | if (acpar.hotdrop) { |
5365f802 JE |
225 | read_unlock_bh(&table->lock); |
226 | return NF_DROP; | |
227 | } | |
1da177e4 LT |
228 | |
229 | /* increase counter */ | |
230 | (*(counter_base + i)).pcnt++; | |
3db05fea | 231 | (*(counter_base + i)).bcnt += skb->len; |
1da177e4 LT |
232 | |
233 | /* these should only watch: not modify, nor tell us | |
7f495ad9 IM |
234 | * what to do with the packet |
235 | */ | |
de74c169 | 236 | EBT_WATCHER_ITERATE(point, ebt_do_watcher, skb, &acpar); |
1da177e4 LT |
237 | |
238 | t = (struct ebt_entry_target *) | |
239 | (((char *)point) + point->target_offset); | |
240 | /* standard target */ | |
241 | if (!t->u.target->target) | |
242 | verdict = ((struct ebt_standard_target *)t)->verdict; | |
7eb35586 | 243 | else { |
de74c169 JE |
244 | acpar.target = t->u.target; |
245 | acpar.targinfo = t->data; | |
246 | verdict = t->u.target->target(skb, &acpar); | |
7eb35586 | 247 | } |
1da177e4 LT |
248 | if (verdict == EBT_ACCEPT) { |
249 | read_unlock_bh(&table->lock); | |
250 | return NF_ACCEPT; | |
251 | } | |
252 | if (verdict == EBT_DROP) { | |
253 | read_unlock_bh(&table->lock); | |
254 | return NF_DROP; | |
255 | } | |
256 | if (verdict == EBT_RETURN) { | |
257 | letsreturn: | |
258 | #ifdef CONFIG_NETFILTER_DEBUG | |
259 | if (sp == 0) { | |
260 | BUGPRINT("RETURN on base chain"); | |
261 | /* act like this is EBT_CONTINUE */ | |
262 | goto letscontinue; | |
263 | } | |
264 | #endif | |
265 | sp--; | |
266 | /* put all the local variables right */ | |
267 | i = cs[sp].n; | |
268 | chaininfo = cs[sp].chaininfo; | |
269 | nentries = chaininfo->nentries; | |
270 | point = cs[sp].e; | |
271 | counter_base = cb_base + | |
272 | chaininfo->counter_offset; | |
273 | continue; | |
274 | } | |
275 | if (verdict == EBT_CONTINUE) | |
276 | goto letscontinue; | |
277 | #ifdef CONFIG_NETFILTER_DEBUG | |
278 | if (verdict < 0) { | |
279 | BUGPRINT("bogus standard verdict\n"); | |
280 | read_unlock_bh(&table->lock); | |
281 | return NF_DROP; | |
282 | } | |
283 | #endif | |
284 | /* jump to a udc */ | |
285 | cs[sp].n = i + 1; | |
286 | cs[sp].chaininfo = chaininfo; | |
98e86403 | 287 | cs[sp].e = ebt_next_entry(point); |
1da177e4 LT |
288 | i = 0; |
289 | chaininfo = (struct ebt_entries *) (base + verdict); | |
290 | #ifdef CONFIG_NETFILTER_DEBUG | |
291 | if (chaininfo->distinguisher) { | |
292 | BUGPRINT("jump to non-chain\n"); | |
293 | read_unlock_bh(&table->lock); | |
294 | return NF_DROP; | |
295 | } | |
296 | #endif | |
297 | nentries = chaininfo->nentries; | |
298 | point = (struct ebt_entry *)chaininfo->data; | |
299 | counter_base = cb_base + chaininfo->counter_offset; | |
300 | sp++; | |
301 | continue; | |
302 | letscontinue: | |
98e86403 | 303 | point = ebt_next_entry(point); |
1da177e4 LT |
304 | i++; |
305 | } | |
306 | ||
307 | /* I actually like this :) */ | |
308 | if (chaininfo->policy == EBT_RETURN) | |
309 | goto letsreturn; | |
310 | if (chaininfo->policy == EBT_ACCEPT) { | |
311 | read_unlock_bh(&table->lock); | |
312 | return NF_ACCEPT; | |
313 | } | |
314 | read_unlock_bh(&table->lock); | |
315 | return NF_DROP; | |
316 | } | |
317 | ||
318 | /* If it succeeds, returns element and locks mutex */ | |
319 | static inline void * | |
320 | find_inlist_lock_noload(struct list_head *head, const char *name, int *error, | |
052a4bc4 | 321 | struct mutex *mutex) |
1da177e4 | 322 | { |
df0933dc PM |
323 | struct { |
324 | struct list_head list; | |
325 | char name[EBT_FUNCTION_MAXNAMELEN]; | |
326 | } *e; | |
1da177e4 | 327 | |
7926dbfa | 328 | mutex_lock(mutex); |
df0933dc PM |
329 | list_for_each_entry(e, head, list) { |
330 | if (strcmp(e->name, name) == 0) | |
331 | return e; | |
1da177e4 | 332 | } |
df0933dc PM |
333 | *error = -ENOENT; |
334 | mutex_unlock(mutex); | |
335 | return NULL; | |
1da177e4 LT |
336 | } |
337 | ||
1da177e4 LT |
338 | static void * |
339 | find_inlist_lock(struct list_head *head, const char *name, const char *prefix, | |
052a4bc4 | 340 | int *error, struct mutex *mutex) |
1da177e4 | 341 | { |
95a5afca JB |
342 | return try_then_request_module( |
343 | find_inlist_lock_noload(head, name, error, mutex), | |
344 | "%s%s", prefix, name); | |
1da177e4 | 345 | } |
1da177e4 LT |
346 | |
347 | static inline struct ebt_table * | |
511061e2 AD |
348 | find_table_lock(struct net *net, const char *name, int *error, |
349 | struct mutex *mutex) | |
1da177e4 | 350 | { |
511061e2 AD |
351 | return find_inlist_lock(&net->xt.tables[NFPROTO_BRIDGE], name, |
352 | "ebtable_", error, mutex); | |
1da177e4 LT |
353 | } |
354 | ||
1da177e4 | 355 | static inline int |
9b4fce7a JE |
356 | ebt_check_match(struct ebt_entry_match *m, struct xt_mtchk_param *par, |
357 | unsigned int *cnt) | |
1da177e4 | 358 | { |
9b4fce7a | 359 | const struct ebt_entry *e = par->entryinfo; |
043ef46c | 360 | struct xt_match *match; |
14197d54 | 361 | size_t left = ((char *)e + e->watchers_offset) - (char *)m; |
1da177e4 LT |
362 | int ret; |
363 | ||
14197d54 AV |
364 | if (left < sizeof(struct ebt_entry_match) || |
365 | left - sizeof(struct ebt_entry_match) < m->match_size) | |
1da177e4 | 366 | return -EINVAL; |
043ef46c | 367 | |
bcf49342 PS |
368 | match = xt_find_match(NFPROTO_BRIDGE, m->u.name, 0); |
369 | if (IS_ERR(match) || match->family != NFPROTO_BRIDGE) { | |
370 | request_module("ebt_%s", m->u.name); | |
371 | match = xt_find_match(NFPROTO_BRIDGE, m->u.name, 0); | |
372 | } | |
043ef46c JE |
373 | if (IS_ERR(match)) |
374 | return PTR_ERR(match); | |
043ef46c JE |
375 | m->u.match = match; |
376 | ||
9b4fce7a JE |
377 | par->match = match; |
378 | par->matchinfo = m->data; | |
916a917d | 379 | ret = xt_check_match(par, m->match_size, |
9b4fce7a | 380 | e->ethproto, e->invflags & EBT_IPROTO); |
043ef46c JE |
381 | if (ret < 0) { |
382 | module_put(match->me); | |
383 | return ret; | |
1da177e4 | 384 | } |
043ef46c | 385 | |
1da177e4 LT |
386 | (*cnt)++; |
387 | return 0; | |
388 | } | |
389 | ||
390 | static inline int | |
af5d6dc2 JE |
391 | ebt_check_watcher(struct ebt_entry_watcher *w, struct xt_tgchk_param *par, |
392 | unsigned int *cnt) | |
1da177e4 | 393 | { |
af5d6dc2 | 394 | const struct ebt_entry *e = par->entryinfo; |
043ef46c | 395 | struct xt_target *watcher; |
14197d54 | 396 | size_t left = ((char *)e + e->target_offset) - (char *)w; |
1da177e4 LT |
397 | int ret; |
398 | ||
14197d54 AV |
399 | if (left < sizeof(struct ebt_entry_watcher) || |
400 | left - sizeof(struct ebt_entry_watcher) < w->watcher_size) | |
1da177e4 | 401 | return -EINVAL; |
043ef46c | 402 | |
d2a7b6ba | 403 | watcher = xt_request_find_target(NFPROTO_BRIDGE, w->u.name, 0); |
043ef46c JE |
404 | if (IS_ERR(watcher)) |
405 | return PTR_ERR(watcher); | |
043ef46c JE |
406 | w->u.watcher = watcher; |
407 | ||
af5d6dc2 JE |
408 | par->target = watcher; |
409 | par->targinfo = w->data; | |
916a917d | 410 | ret = xt_check_target(par, w->watcher_size, |
af5d6dc2 | 411 | e->ethproto, e->invflags & EBT_IPROTO); |
043ef46c JE |
412 | if (ret < 0) { |
413 | module_put(watcher->me); | |
414 | return ret; | |
1da177e4 | 415 | } |
043ef46c | 416 | |
1da177e4 LT |
417 | (*cnt)++; |
418 | return 0; | |
419 | } | |
420 | ||
d5d1baa1 | 421 | static int ebt_verify_pointers(const struct ebt_replace *repl, |
70fe9af4 | 422 | struct ebt_table_info *newinfo) |
1da177e4 | 423 | { |
70fe9af4 AV |
424 | unsigned int limit = repl->entries_size; |
425 | unsigned int valid_hooks = repl->valid_hooks; | |
426 | unsigned int offset = 0; | |
1da177e4 LT |
427 | int i; |
428 | ||
e4fd77de AV |
429 | for (i = 0; i < NF_BR_NUMHOOKS; i++) |
430 | newinfo->hook_entry[i] = NULL; | |
431 | ||
432 | newinfo->entries_size = repl->entries_size; | |
433 | newinfo->nentries = repl->nentries; | |
434 | ||
70fe9af4 AV |
435 | while (offset < limit) { |
436 | size_t left = limit - offset; | |
437 | struct ebt_entry *e = (void *)newinfo->entries + offset; | |
bb2ef25c | 438 | |
70fe9af4 | 439 | if (left < sizeof(unsigned int)) |
1da177e4 | 440 | break; |
70fe9af4 AV |
441 | |
442 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { | |
443 | if ((valid_hooks & (1 << i)) == 0) | |
444 | continue; | |
1e419cd9 AV |
445 | if ((char __user *)repl->hook_entry[i] == |
446 | repl->entries + offset) | |
70fe9af4 AV |
447 | break; |
448 | } | |
449 | ||
450 | if (i != NF_BR_NUMHOOKS || !(e->bitmask & EBT_ENTRY_OR_ENTRIES)) { | |
451 | if (e->bitmask != 0) { | |
452 | /* we make userspace set this right, | |
7f495ad9 IM |
453 | * so there is no misunderstanding |
454 | */ | |
70fe9af4 AV |
455 | BUGPRINT("EBT_ENTRY_OR_ENTRIES shouldn't be set " |
456 | "in distinguisher\n"); | |
457 | return -EINVAL; | |
458 | } | |
459 | if (i != NF_BR_NUMHOOKS) | |
460 | newinfo->hook_entry[i] = (struct ebt_entries *)e; | |
461 | if (left < sizeof(struct ebt_entries)) | |
462 | break; | |
463 | offset += sizeof(struct ebt_entries); | |
464 | } else { | |
465 | if (left < sizeof(struct ebt_entry)) | |
466 | break; | |
467 | if (left < e->next_offset) | |
468 | break; | |
1756de26 FW |
469 | if (e->next_offset < sizeof(struct ebt_entry)) |
470 | return -EINVAL; | |
70fe9af4 | 471 | offset += e->next_offset; |
1da177e4 | 472 | } |
22b440bf | 473 | } |
70fe9af4 AV |
474 | if (offset != limit) { |
475 | BUGPRINT("entries_size too small\n"); | |
476 | return -EINVAL; | |
477 | } | |
e4fd77de AV |
478 | |
479 | /* check if all valid hooks have a chain */ | |
480 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { | |
481 | if (!newinfo->hook_entry[i] && | |
482 | (valid_hooks & (1 << i))) { | |
483 | BUGPRINT("Valid hook without chain\n"); | |
484 | return -EINVAL; | |
485 | } | |
486 | } | |
22b440bf | 487 | return 0; |
22b440bf AV |
488 | } |
489 | ||
7f495ad9 | 490 | /* this one is very careful, as it is the first function |
22b440bf AV |
491 | * to parse the userspace data |
492 | */ | |
493 | static inline int | |
d5d1baa1 | 494 | ebt_check_entry_size_and_hooks(const struct ebt_entry *e, |
052a4bc4 IM |
495 | const struct ebt_table_info *newinfo, |
496 | unsigned int *n, unsigned int *cnt, | |
497 | unsigned int *totalcnt, unsigned int *udc_cnt) | |
22b440bf | 498 | { |
22b440bf AV |
499 | int i; |
500 | ||
501 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { | |
0e795531 | 502 | if ((void *)e == (void *)newinfo->hook_entry[i]) |
22b440bf AV |
503 | break; |
504 | } | |
505 | /* beginning of a new chain | |
7f495ad9 IM |
506 | * if i == NF_BR_NUMHOOKS it must be a user defined chain |
507 | */ | |
22b440bf | 508 | if (i != NF_BR_NUMHOOKS || !e->bitmask) { |
1da177e4 | 509 | /* this checks if the previous chain has as many entries |
7f495ad9 IM |
510 | * as it said it has |
511 | */ | |
1da177e4 LT |
512 | if (*n != *cnt) { |
513 | BUGPRINT("nentries does not equal the nr of entries " | |
9d6f229f | 514 | "in the chain\n"); |
1da177e4 LT |
515 | return -EINVAL; |
516 | } | |
1da177e4 LT |
517 | if (((struct ebt_entries *)e)->policy != EBT_DROP && |
518 | ((struct ebt_entries *)e)->policy != EBT_ACCEPT) { | |
519 | /* only RETURN from udc */ | |
520 | if (i != NF_BR_NUMHOOKS || | |
521 | ((struct ebt_entries *)e)->policy != EBT_RETURN) { | |
522 | BUGPRINT("bad policy\n"); | |
523 | return -EINVAL; | |
524 | } | |
525 | } | |
526 | if (i == NF_BR_NUMHOOKS) /* it's a user defined chain */ | |
527 | (*udc_cnt)++; | |
1da177e4 LT |
528 | if (((struct ebt_entries *)e)->counter_offset != *totalcnt) { |
529 | BUGPRINT("counter_offset != totalcnt"); | |
530 | return -EINVAL; | |
531 | } | |
532 | *n = ((struct ebt_entries *)e)->nentries; | |
533 | *cnt = 0; | |
534 | return 0; | |
535 | } | |
536 | /* a plain old entry, heh */ | |
537 | if (sizeof(struct ebt_entry) > e->watchers_offset || | |
538 | e->watchers_offset > e->target_offset || | |
539 | e->target_offset >= e->next_offset) { | |
540 | BUGPRINT("entry offsets not in right order\n"); | |
541 | return -EINVAL; | |
542 | } | |
543 | /* this is not checked anywhere else */ | |
544 | if (e->next_offset - e->target_offset < sizeof(struct ebt_entry_target)) { | |
545 | BUGPRINT("target size too small\n"); | |
546 | return -EINVAL; | |
547 | } | |
1da177e4 LT |
548 | (*cnt)++; |
549 | (*totalcnt)++; | |
550 | return 0; | |
551 | } | |
552 | ||
abcdd9a6 | 553 | struct ebt_cl_stack { |
1da177e4 LT |
554 | struct ebt_chainstack cs; |
555 | int from; | |
556 | unsigned int hookmask; | |
557 | }; | |
558 | ||
7f495ad9 | 559 | /* We need these positions to check that the jumps to a different part of the |
1da177e4 LT |
560 | * entries is a jump to the beginning of a new chain. |
561 | */ | |
562 | static inline int | |
563 | ebt_get_udc_positions(struct ebt_entry *e, struct ebt_table_info *newinfo, | |
052a4bc4 | 564 | unsigned int *n, struct ebt_cl_stack *udc) |
1da177e4 LT |
565 | { |
566 | int i; | |
567 | ||
568 | /* we're only interested in chain starts */ | |
40642f95 | 569 | if (e->bitmask) |
1da177e4 LT |
570 | return 0; |
571 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { | |
1da177e4 LT |
572 | if (newinfo->hook_entry[i] == (struct ebt_entries *)e) |
573 | break; | |
574 | } | |
575 | /* only care about udc */ | |
576 | if (i != NF_BR_NUMHOOKS) | |
577 | return 0; | |
578 | ||
579 | udc[*n].cs.chaininfo = (struct ebt_entries *)e; | |
580 | /* these initialisations are depended on later in check_chainloops() */ | |
581 | udc[*n].cs.n = 0; | |
582 | udc[*n].hookmask = 0; | |
583 | ||
584 | (*n)++; | |
585 | return 0; | |
586 | } | |
587 | ||
588 | static inline int | |
f54e9367 | 589 | ebt_cleanup_match(struct ebt_entry_match *m, struct net *net, unsigned int *i) |
1da177e4 | 590 | { |
6be3d859 JE |
591 | struct xt_mtdtor_param par; |
592 | ||
1da177e4 LT |
593 | if (i && (*i)-- == 0) |
594 | return 1; | |
1da177e4 | 595 | |
f54e9367 | 596 | par.net = net; |
6be3d859 JE |
597 | par.match = m->u.match; |
598 | par.matchinfo = m->data; | |
916a917d | 599 | par.family = NFPROTO_BRIDGE; |
6be3d859 JE |
600 | if (par.match->destroy != NULL) |
601 | par.match->destroy(&par); | |
602 | module_put(par.match->me); | |
1da177e4 LT |
603 | return 0; |
604 | } | |
605 | ||
606 | static inline int | |
add67461 | 607 | ebt_cleanup_watcher(struct ebt_entry_watcher *w, struct net *net, unsigned int *i) |
1da177e4 | 608 | { |
a2df1648 JE |
609 | struct xt_tgdtor_param par; |
610 | ||
1da177e4 LT |
611 | if (i && (*i)-- == 0) |
612 | return 1; | |
1da177e4 | 613 | |
add67461 | 614 | par.net = net; |
a2df1648 JE |
615 | par.target = w->u.watcher; |
616 | par.targinfo = w->data; | |
916a917d | 617 | par.family = NFPROTO_BRIDGE; |
a2df1648 JE |
618 | if (par.target->destroy != NULL) |
619 | par.target->destroy(&par); | |
620 | module_put(par.target->me); | |
1da177e4 LT |
621 | return 0; |
622 | } | |
623 | ||
624 | static inline int | |
f54e9367 | 625 | ebt_cleanup_entry(struct ebt_entry *e, struct net *net, unsigned int *cnt) |
1da177e4 | 626 | { |
a2df1648 | 627 | struct xt_tgdtor_param par; |
1da177e4 LT |
628 | struct ebt_entry_target *t; |
629 | ||
40642f95 | 630 | if (e->bitmask == 0) |
1da177e4 LT |
631 | return 0; |
632 | /* we're done */ | |
633 | if (cnt && (*cnt)-- == 0) | |
634 | return 1; | |
add67461 | 635 | EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, net, NULL); |
f54e9367 | 636 | EBT_MATCH_ITERATE(e, ebt_cleanup_match, net, NULL); |
1da177e4 | 637 | t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
1da177e4 | 638 | |
add67461 | 639 | par.net = net; |
a2df1648 JE |
640 | par.target = t->u.target; |
641 | par.targinfo = t->data; | |
916a917d | 642 | par.family = NFPROTO_BRIDGE; |
a2df1648 JE |
643 | if (par.target->destroy != NULL) |
644 | par.target->destroy(&par); | |
645 | module_put(par.target->me); | |
1da177e4 LT |
646 | return 0; |
647 | } | |
648 | ||
649 | static inline int | |
d5d1baa1 | 650 | ebt_check_entry(struct ebt_entry *e, struct net *net, |
052a4bc4 IM |
651 | const struct ebt_table_info *newinfo, |
652 | const char *name, unsigned int *cnt, | |
653 | struct ebt_cl_stack *cl_s, unsigned int udc_cnt) | |
1da177e4 LT |
654 | { |
655 | struct ebt_entry_target *t; | |
043ef46c | 656 | struct xt_target *target; |
1da177e4 | 657 | unsigned int i, j, hook = 0, hookmask = 0; |
44f9a2fd | 658 | size_t gap; |
1da177e4 | 659 | int ret; |
6be3d859 | 660 | struct xt_mtchk_param mtpar; |
af5d6dc2 | 661 | struct xt_tgchk_param tgpar; |
1da177e4 LT |
662 | |
663 | /* don't mess with the struct ebt_entries */ | |
40642f95 | 664 | if (e->bitmask == 0) |
1da177e4 LT |
665 | return 0; |
666 | ||
667 | if (e->bitmask & ~EBT_F_MASK) { | |
668 | BUGPRINT("Unknown flag for bitmask\n"); | |
669 | return -EINVAL; | |
670 | } | |
671 | if (e->invflags & ~EBT_INV_MASK) { | |
672 | BUGPRINT("Unknown flag for inv bitmask\n"); | |
673 | return -EINVAL; | |
674 | } | |
c1bc1d25 | 675 | if ((e->bitmask & EBT_NOPROTO) && (e->bitmask & EBT_802_3)) { |
1da177e4 LT |
676 | BUGPRINT("NOPROTO & 802_3 not allowed\n"); |
677 | return -EINVAL; | |
678 | } | |
679 | /* what hook do we belong to? */ | |
680 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { | |
f7da79d9 | 681 | if (!newinfo->hook_entry[i]) |
1da177e4 LT |
682 | continue; |
683 | if ((char *)newinfo->hook_entry[i] < (char *)e) | |
684 | hook = i; | |
685 | else | |
686 | break; | |
687 | } | |
688 | /* (1 << NF_BR_NUMHOOKS) tells the check functions the rule is on | |
7f495ad9 IM |
689 | * a base chain |
690 | */ | |
1da177e4 LT |
691 | if (i < NF_BR_NUMHOOKS) |
692 | hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); | |
693 | else { | |
694 | for (i = 0; i < udc_cnt; i++) | |
695 | if ((char *)(cl_s[i].cs.chaininfo) > (char *)e) | |
696 | break; | |
697 | if (i == 0) | |
698 | hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); | |
699 | else | |
700 | hookmask = cl_s[i - 1].hookmask; | |
701 | } | |
702 | i = 0; | |
9b4fce7a | 703 | |
add67461 | 704 | mtpar.net = tgpar.net = net; |
af5d6dc2 JE |
705 | mtpar.table = tgpar.table = name; |
706 | mtpar.entryinfo = tgpar.entryinfo = e; | |
707 | mtpar.hook_mask = tgpar.hook_mask = hookmask; | |
916a917d | 708 | mtpar.family = tgpar.family = NFPROTO_BRIDGE; |
6be3d859 | 709 | ret = EBT_MATCH_ITERATE(e, ebt_check_match, &mtpar, &i); |
1da177e4 LT |
710 | if (ret != 0) |
711 | goto cleanup_matches; | |
712 | j = 0; | |
af5d6dc2 | 713 | ret = EBT_WATCHER_ITERATE(e, ebt_check_watcher, &tgpar, &j); |
1da177e4 LT |
714 | if (ret != 0) |
715 | goto cleanup_watchers; | |
716 | t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); | |
44f9a2fd | 717 | gap = e->next_offset - e->target_offset; |
1da177e4 | 718 | |
d2a7b6ba | 719 | target = xt_request_find_target(NFPROTO_BRIDGE, t->u.name, 0); |
043ef46c JE |
720 | if (IS_ERR(target)) { |
721 | ret = PTR_ERR(target); | |
001a18d3 | 722 | goto cleanup_watchers; |
001a18d3 JE |
723 | } |
724 | ||
1da177e4 LT |
725 | t->u.target = target; |
726 | if (t->u.target == &ebt_standard_target) { | |
14197d54 | 727 | if (gap < sizeof(struct ebt_standard_target)) { |
1da177e4 LT |
728 | BUGPRINT("Standard target size too big\n"); |
729 | ret = -EFAULT; | |
730 | goto cleanup_watchers; | |
731 | } | |
732 | if (((struct ebt_standard_target *)t)->verdict < | |
733 | -NUM_STANDARD_TARGETS) { | |
734 | BUGPRINT("Invalid standard target\n"); | |
735 | ret = -EFAULT; | |
736 | goto cleanup_watchers; | |
737 | } | |
18219d3f JE |
738 | } else if (t->target_size > gap - sizeof(struct ebt_entry_target)) { |
739 | module_put(t->u.target->me); | |
740 | ret = -EFAULT; | |
741 | goto cleanup_watchers; | |
043ef46c JE |
742 | } |
743 | ||
af5d6dc2 JE |
744 | tgpar.target = target; |
745 | tgpar.targinfo = t->data; | |
916a917d | 746 | ret = xt_check_target(&tgpar, t->target_size, |
af5d6dc2 | 747 | e->ethproto, e->invflags & EBT_IPROTO); |
043ef46c JE |
748 | if (ret < 0) { |
749 | module_put(target->me); | |
18219d3f | 750 | goto cleanup_watchers; |
1da177e4 LT |
751 | } |
752 | (*cnt)++; | |
753 | return 0; | |
754 | cleanup_watchers: | |
add67461 | 755 | EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, net, &j); |
1da177e4 | 756 | cleanup_matches: |
f54e9367 | 757 | EBT_MATCH_ITERATE(e, ebt_cleanup_match, net, &i); |
1da177e4 LT |
758 | return ret; |
759 | } | |
760 | ||
7f495ad9 | 761 | /* checks for loops and sets the hook mask for udc |
1da177e4 LT |
762 | * the hook mask for udc tells us from which base chains the udc can be |
763 | * accessed. This mask is a parameter to the check() functions of the extensions | |
764 | */ | |
d5d1baa1 | 765 | static int check_chainloops(const struct ebt_entries *chain, struct ebt_cl_stack *cl_s, |
052a4bc4 | 766 | unsigned int udc_cnt, unsigned int hooknr, char *base) |
1da177e4 LT |
767 | { |
768 | int i, chain_nr = -1, pos = 0, nentries = chain->nentries, verdict; | |
d5d1baa1 JE |
769 | const struct ebt_entry *e = (struct ebt_entry *)chain->data; |
770 | const struct ebt_entry_target *t; | |
1da177e4 LT |
771 | |
772 | while (pos < nentries || chain_nr != -1) { | |
773 | /* end of udc, go back one 'recursion' step */ | |
774 | if (pos == nentries) { | |
775 | /* put back values of the time when this chain was called */ | |
776 | e = cl_s[chain_nr].cs.e; | |
777 | if (cl_s[chain_nr].from != -1) | |
778 | nentries = | |
779 | cl_s[cl_s[chain_nr].from].cs.chaininfo->nentries; | |
780 | else | |
781 | nentries = chain->nentries; | |
782 | pos = cl_s[chain_nr].cs.n; | |
783 | /* make sure we won't see a loop that isn't one */ | |
784 | cl_s[chain_nr].cs.n = 0; | |
785 | chain_nr = cl_s[chain_nr].from; | |
786 | if (pos == nentries) | |
787 | continue; | |
788 | } | |
789 | t = (struct ebt_entry_target *) | |
790 | (((char *)e) + e->target_offset); | |
791 | if (strcmp(t->u.name, EBT_STANDARD_TARGET)) | |
792 | goto letscontinue; | |
793 | if (e->target_offset + sizeof(struct ebt_standard_target) > | |
794 | e->next_offset) { | |
795 | BUGPRINT("Standard target size too big\n"); | |
796 | return -1; | |
797 | } | |
798 | verdict = ((struct ebt_standard_target *)t)->verdict; | |
799 | if (verdict >= 0) { /* jump to another chain */ | |
800 | struct ebt_entries *hlp2 = | |
801 | (struct ebt_entries *)(base + verdict); | |
802 | for (i = 0; i < udc_cnt; i++) | |
803 | if (hlp2 == cl_s[i].cs.chaininfo) | |
804 | break; | |
805 | /* bad destination or loop */ | |
806 | if (i == udc_cnt) { | |
807 | BUGPRINT("bad destination\n"); | |
808 | return -1; | |
809 | } | |
810 | if (cl_s[i].cs.n) { | |
811 | BUGPRINT("loop\n"); | |
812 | return -1; | |
813 | } | |
98a0824a AV |
814 | if (cl_s[i].hookmask & (1 << hooknr)) |
815 | goto letscontinue; | |
816 | /* this can't be 0, so the loop test is correct */ | |
1da177e4 LT |
817 | cl_s[i].cs.n = pos + 1; |
818 | pos = 0; | |
98e86403 | 819 | cl_s[i].cs.e = ebt_next_entry(e); |
1da177e4 LT |
820 | e = (struct ebt_entry *)(hlp2->data); |
821 | nentries = hlp2->nentries; | |
822 | cl_s[i].from = chain_nr; | |
823 | chain_nr = i; | |
824 | /* this udc is accessible from the base chain for hooknr */ | |
825 | cl_s[i].hookmask |= (1 << hooknr); | |
826 | continue; | |
827 | } | |
828 | letscontinue: | |
98e86403 | 829 | e = ebt_next_entry(e); |
1da177e4 LT |
830 | pos++; |
831 | } | |
832 | return 0; | |
833 | } | |
834 | ||
835 | /* do the parsing of the table/chains/entries/matches/watchers/targets, heh */ | |
d5d1baa1 | 836 | static int translate_table(struct net *net, const char *name, |
a83d8e8d | 837 | struct ebt_table_info *newinfo) |
1da177e4 LT |
838 | { |
839 | unsigned int i, j, k, udc_cnt; | |
840 | int ret; | |
841 | struct ebt_cl_stack *cl_s = NULL; /* used in the checking for chain loops */ | |
842 | ||
843 | i = 0; | |
1f072c96 | 844 | while (i < NF_BR_NUMHOOKS && !newinfo->hook_entry[i]) |
1da177e4 LT |
845 | i++; |
846 | if (i == NF_BR_NUMHOOKS) { | |
847 | BUGPRINT("No valid hooks specified\n"); | |
848 | return -EINVAL; | |
849 | } | |
1f072c96 | 850 | if (newinfo->hook_entry[i] != (struct ebt_entries *)newinfo->entries) { |
1da177e4 LT |
851 | BUGPRINT("Chains don't start at beginning\n"); |
852 | return -EINVAL; | |
853 | } | |
854 | /* make sure chains are ordered after each other in same order | |
7f495ad9 IM |
855 | * as their corresponding hooks |
856 | */ | |
1da177e4 | 857 | for (j = i + 1; j < NF_BR_NUMHOOKS; j++) { |
1f072c96 | 858 | if (!newinfo->hook_entry[j]) |
1da177e4 | 859 | continue; |
1f072c96 | 860 | if (newinfo->hook_entry[j] <= newinfo->hook_entry[i]) { |
1da177e4 LT |
861 | BUGPRINT("Hook order must be followed\n"); |
862 | return -EINVAL; | |
863 | } | |
864 | i = j; | |
865 | } | |
866 | ||
1da177e4 LT |
867 | /* do some early checkings and initialize some things */ |
868 | i = 0; /* holds the expected nr. of entries for the chain */ | |
869 | j = 0; /* holds the up to now counted entries for the chain */ | |
870 | k = 0; /* holds the total nr. of entries, should equal | |
7f495ad9 IM |
871 | * newinfo->nentries afterwards |
872 | */ | |
1da177e4 LT |
873 | udc_cnt = 0; /* will hold the nr. of user defined chains (udc) */ |
874 | ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, | |
0e795531 AV |
875 | ebt_check_entry_size_and_hooks, newinfo, |
876 | &i, &j, &k, &udc_cnt); | |
1da177e4 LT |
877 | |
878 | if (ret != 0) | |
879 | return ret; | |
880 | ||
881 | if (i != j) { | |
882 | BUGPRINT("nentries does not equal the nr of entries in the " | |
9d6f229f | 883 | "(last) chain\n"); |
1da177e4 LT |
884 | return -EINVAL; |
885 | } | |
886 | if (k != newinfo->nentries) { | |
887 | BUGPRINT("Total nentries is wrong\n"); | |
888 | return -EINVAL; | |
889 | } | |
890 | ||
1da177e4 | 891 | /* get the location of the udc, put them in an array |
7f495ad9 IM |
892 | * while we're at it, allocate the chainstack |
893 | */ | |
1da177e4 LT |
894 | if (udc_cnt) { |
895 | /* this will get free'd in do_replace()/ebt_register_table() | |
7f495ad9 IM |
896 | * if an error occurs |
897 | */ | |
7ad4d2f6 | 898 | newinfo->chainstack = |
53b8a315 | 899 | vmalloc(nr_cpu_ids * sizeof(*(newinfo->chainstack))); |
1da177e4 LT |
900 | if (!newinfo->chainstack) |
901 | return -ENOMEM; | |
6f912042 | 902 | for_each_possible_cpu(i) { |
1da177e4 | 903 | newinfo->chainstack[i] = |
18bc89aa | 904 | vmalloc(udc_cnt * sizeof(*(newinfo->chainstack[0]))); |
1da177e4 LT |
905 | if (!newinfo->chainstack[i]) { |
906 | while (i) | |
907 | vfree(newinfo->chainstack[--i]); | |
908 | vfree(newinfo->chainstack); | |
909 | newinfo->chainstack = NULL; | |
910 | return -ENOMEM; | |
911 | } | |
912 | } | |
913 | ||
18bc89aa | 914 | cl_s = vmalloc(udc_cnt * sizeof(*cl_s)); |
1da177e4 LT |
915 | if (!cl_s) |
916 | return -ENOMEM; | |
917 | i = 0; /* the i'th udc */ | |
918 | EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, | |
177abc34 | 919 | ebt_get_udc_positions, newinfo, &i, cl_s); |
1da177e4 LT |
920 | /* sanity check */ |
921 | if (i != udc_cnt) { | |
922 | BUGPRINT("i != udc_cnt\n"); | |
923 | vfree(cl_s); | |
924 | return -EFAULT; | |
925 | } | |
926 | } | |
927 | ||
928 | /* Check for loops */ | |
929 | for (i = 0; i < NF_BR_NUMHOOKS; i++) | |
1f072c96 | 930 | if (newinfo->hook_entry[i]) |
1da177e4 LT |
931 | if (check_chainloops(newinfo->hook_entry[i], |
932 | cl_s, udc_cnt, i, newinfo->entries)) { | |
68d31872 | 933 | vfree(cl_s); |
1da177e4 LT |
934 | return -EINVAL; |
935 | } | |
936 | ||
96de0e25 | 937 | /* we now know the following (along with E=mc²): |
7f495ad9 IM |
938 | * - the nr of entries in each chain is right |
939 | * - the size of the allocated space is right | |
940 | * - all valid hooks have a corresponding chain | |
941 | * - there are no loops | |
942 | * - wrong data can still be on the level of a single entry | |
943 | * - could be there are jumps to places that are not the | |
944 | * beginning of a chain. This can only occur in chains that | |
945 | * are not accessible from any base chains, so we don't care. | |
946 | */ | |
1da177e4 LT |
947 | |
948 | /* used to know what we need to clean up if something goes wrong */ | |
949 | i = 0; | |
950 | ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, | |
a83d8e8d | 951 | ebt_check_entry, net, newinfo, name, &i, cl_s, udc_cnt); |
1da177e4 LT |
952 | if (ret != 0) { |
953 | EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, | |
f54e9367 | 954 | ebt_cleanup_entry, net, &i); |
1da177e4 | 955 | } |
68d31872 | 956 | vfree(cl_s); |
1da177e4 LT |
957 | return ret; |
958 | } | |
959 | ||
960 | /* called under write_lock */ | |
d5d1baa1 | 961 | static void get_counters(const struct ebt_counter *oldcounters, |
052a4bc4 | 962 | struct ebt_counter *counters, unsigned int nentries) |
1da177e4 LT |
963 | { |
964 | int i, cpu; | |
965 | struct ebt_counter *counter_base; | |
966 | ||
967 | /* counters of cpu 0 */ | |
968 | memcpy(counters, oldcounters, | |
c8923c6b DM |
969 | sizeof(struct ebt_counter) * nentries); |
970 | ||
1da177e4 | 971 | /* add other counters to those of cpu 0 */ |
6f912042 | 972 | for_each_possible_cpu(cpu) { |
c8923c6b DM |
973 | if (cpu == 0) |
974 | continue; | |
1da177e4 LT |
975 | counter_base = COUNTER_BASE(oldcounters, nentries, cpu); |
976 | for (i = 0; i < nentries; i++) { | |
977 | counters[i].pcnt += counter_base[i].pcnt; | |
978 | counters[i].bcnt += counter_base[i].bcnt; | |
979 | } | |
980 | } | |
981 | } | |
982 | ||
e788759f FW |
983 | static int do_replace_finish(struct net *net, struct ebt_replace *repl, |
984 | struct ebt_table_info *newinfo) | |
1da177e4 | 985 | { |
e788759f | 986 | int ret, i; |
1da177e4 LT |
987 | struct ebt_counter *counterstmp = NULL; |
988 | /* used to be able to unlock earlier */ | |
989 | struct ebt_table_info *table; | |
e788759f | 990 | struct ebt_table *t; |
1da177e4 LT |
991 | |
992 | /* the user wants counters back | |
7f495ad9 IM |
993 | * the check on the size is done later, when we have the lock |
994 | */ | |
e788759f FW |
995 | if (repl->num_counters) { |
996 | unsigned long size = repl->num_counters * sizeof(*counterstmp); | |
997 | counterstmp = vmalloc(size); | |
998 | if (!counterstmp) | |
999 | return -ENOMEM; | |
1da177e4 | 1000 | } |
1da177e4 | 1001 | |
1da177e4 | 1002 | newinfo->chainstack = NULL; |
e788759f | 1003 | ret = ebt_verify_pointers(repl, newinfo); |
1bc2326c AV |
1004 | if (ret != 0) |
1005 | goto free_counterstmp; | |
1006 | ||
e788759f | 1007 | ret = translate_table(net, repl->name, newinfo); |
1da177e4 LT |
1008 | |
1009 | if (ret != 0) | |
1010 | goto free_counterstmp; | |
1011 | ||
e788759f | 1012 | t = find_table_lock(net, repl->name, &ret, &ebt_mutex); |
1da177e4 LT |
1013 | if (!t) { |
1014 | ret = -ENOENT; | |
1015 | goto free_iterate; | |
1016 | } | |
1017 | ||
1018 | /* the table doesn't like it */ | |
e788759f | 1019 | if (t->check && (ret = t->check(newinfo, repl->valid_hooks))) |
1da177e4 LT |
1020 | goto free_unlock; |
1021 | ||
e788759f | 1022 | if (repl->num_counters && repl->num_counters != t->private->nentries) { |
1da177e4 LT |
1023 | BUGPRINT("Wrong nr. of counters requested\n"); |
1024 | ret = -EINVAL; | |
1025 | goto free_unlock; | |
1026 | } | |
1027 | ||
1028 | /* we have the mutex lock, so no danger in reading this pointer */ | |
1029 | table = t->private; | |
1030 | /* make sure the table can only be rmmod'ed if it contains no rules */ | |
1031 | if (!table->nentries && newinfo->nentries && !try_module_get(t->me)) { | |
1032 | ret = -ENOENT; | |
1033 | goto free_unlock; | |
1034 | } else if (table->nentries && !newinfo->nentries) | |
1035 | module_put(t->me); | |
1036 | /* we need an atomic snapshot of the counters */ | |
1037 | write_lock_bh(&t->lock); | |
e788759f | 1038 | if (repl->num_counters) |
1da177e4 LT |
1039 | get_counters(t->private->counters, counterstmp, |
1040 | t->private->nentries); | |
1041 | ||
1042 | t->private = newinfo; | |
1043 | write_unlock_bh(&t->lock); | |
57b47a53 | 1044 | mutex_unlock(&ebt_mutex); |
1da177e4 | 1045 | /* so, a user can change the chains while having messed up her counter |
7f495ad9 IM |
1046 | * allocation. Only reason why this is done is because this way the lock |
1047 | * is held only once, while this doesn't bring the kernel into a | |
1048 | * dangerous state. | |
1049 | */ | |
e788759f FW |
1050 | if (repl->num_counters && |
1051 | copy_to_user(repl->counters, counterstmp, | |
1052 | repl->num_counters * sizeof(struct ebt_counter))) { | |
c58dd2dd TG |
1053 | /* Silent error, can't fail, new table is already in place */ |
1054 | net_warn_ratelimited("ebtables: counters copy to user failed while replacing table\n"); | |
1da177e4 | 1055 | } |
1da177e4 LT |
1056 | |
1057 | /* decrease module count and free resources */ | |
1058 | EBT_ENTRY_ITERATE(table->entries, table->entries_size, | |
f54e9367 | 1059 | ebt_cleanup_entry, net, NULL); |
1da177e4 LT |
1060 | |
1061 | vfree(table->entries); | |
1062 | if (table->chainstack) { | |
6f912042 | 1063 | for_each_possible_cpu(i) |
1da177e4 LT |
1064 | vfree(table->chainstack[i]); |
1065 | vfree(table->chainstack); | |
1066 | } | |
1067 | vfree(table); | |
1068 | ||
68d31872 | 1069 | vfree(counterstmp); |
c55fbbb4 ND |
1070 | |
1071 | #ifdef CONFIG_AUDIT | |
1072 | if (audit_enabled) { | |
1073 | struct audit_buffer *ab; | |
1074 | ||
1075 | ab = audit_log_start(current->audit_context, GFP_KERNEL, | |
1076 | AUDIT_NETFILTER_CFG); | |
1077 | if (ab) { | |
1078 | audit_log_format(ab, "table=%s family=%u entries=%u", | |
1079 | repl->name, AF_BRIDGE, repl->nentries); | |
1080 | audit_log_end(ab); | |
1081 | } | |
1082 | } | |
1083 | #endif | |
1da177e4 LT |
1084 | return ret; |
1085 | ||
1086 | free_unlock: | |
57b47a53 | 1087 | mutex_unlock(&ebt_mutex); |
1da177e4 LT |
1088 | free_iterate: |
1089 | EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, | |
f54e9367 | 1090 | ebt_cleanup_entry, net, NULL); |
1da177e4 | 1091 | free_counterstmp: |
68d31872 | 1092 | vfree(counterstmp); |
1da177e4 LT |
1093 | /* can be initialized in translate_table() */ |
1094 | if (newinfo->chainstack) { | |
6f912042 | 1095 | for_each_possible_cpu(i) |
1da177e4 LT |
1096 | vfree(newinfo->chainstack[i]); |
1097 | vfree(newinfo->chainstack); | |
1098 | } | |
e788759f FW |
1099 | return ret; |
1100 | } | |
1101 | ||
1102 | /* replace the table */ | |
1103 | static int do_replace(struct net *net, const void __user *user, | |
1104 | unsigned int len) | |
1105 | { | |
1106 | int ret, countersize; | |
1107 | struct ebt_table_info *newinfo; | |
1108 | struct ebt_replace tmp; | |
1109 | ||
1110 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1111 | return -EFAULT; | |
1112 | ||
1113 | if (len != sizeof(tmp) + tmp.entries_size) { | |
1114 | BUGPRINT("Wrong len argument\n"); | |
1115 | return -EINVAL; | |
1116 | } | |
1117 | ||
1118 | if (tmp.entries_size == 0) { | |
1119 | BUGPRINT("Entries_size never zero\n"); | |
1120 | return -EINVAL; | |
1121 | } | |
1122 | /* overflow check */ | |
1123 | if (tmp.nentries >= ((INT_MAX - sizeof(struct ebt_table_info)) / | |
1124 | NR_CPUS - SMP_CACHE_BYTES) / sizeof(struct ebt_counter)) | |
1125 | return -ENOMEM; | |
1126 | if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter)) | |
1127 | return -ENOMEM; | |
1128 | ||
d846f711 VK |
1129 | tmp.name[sizeof(tmp.name) - 1] = 0; |
1130 | ||
e788759f FW |
1131 | countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids; |
1132 | newinfo = vmalloc(sizeof(*newinfo) + countersize); | |
1133 | if (!newinfo) | |
1134 | return -ENOMEM; | |
1135 | ||
1136 | if (countersize) | |
1137 | memset(newinfo->counters, 0, countersize); | |
1138 | ||
1139 | newinfo->entries = vmalloc(tmp.entries_size); | |
1140 | if (!newinfo->entries) { | |
1141 | ret = -ENOMEM; | |
1142 | goto free_newinfo; | |
1143 | } | |
1144 | if (copy_from_user( | |
1145 | newinfo->entries, tmp.entries, tmp.entries_size) != 0) { | |
1146 | BUGPRINT("Couldn't copy entries from userspace\n"); | |
1147 | ret = -EFAULT; | |
1148 | goto free_entries; | |
1149 | } | |
1150 | ||
1151 | ret = do_replace_finish(net, &tmp, newinfo); | |
1152 | if (ret == 0) | |
1153 | return ret; | |
1da177e4 | 1154 | free_entries: |
68d31872 | 1155 | vfree(newinfo->entries); |
1da177e4 | 1156 | free_newinfo: |
68d31872 | 1157 | vfree(newinfo); |
1da177e4 LT |
1158 | return ret; |
1159 | } | |
1160 | ||
35aad0ff JE |
1161 | struct ebt_table * |
1162 | ebt_register_table(struct net *net, const struct ebt_table *input_table) | |
1da177e4 LT |
1163 | { |
1164 | struct ebt_table_info *newinfo; | |
35aad0ff | 1165 | struct ebt_table *t, *table; |
1e419cd9 | 1166 | struct ebt_replace_kernel *repl; |
1da177e4 | 1167 | int ret, i, countersize; |
df07a81e | 1168 | void *p; |
1da177e4 | 1169 | |
35aad0ff | 1170 | if (input_table == NULL || (repl = input_table->table) == NULL || |
1a9180a2 | 1171 | repl->entries == NULL || repl->entries_size == 0 || |
35aad0ff | 1172 | repl->counters != NULL || input_table->private != NULL) { |
1da177e4 | 1173 | BUGPRINT("Bad table data for ebt_register_table!!!\n"); |
6beceee5 AD |
1174 | return ERR_PTR(-EINVAL); |
1175 | } | |
1176 | ||
1177 | /* Don't add one table to multiple lists. */ | |
35aad0ff | 1178 | table = kmemdup(input_table, sizeof(struct ebt_table), GFP_KERNEL); |
6beceee5 AD |
1179 | if (!table) { |
1180 | ret = -ENOMEM; | |
1181 | goto out; | |
1da177e4 LT |
1182 | } |
1183 | ||
53b8a315 | 1184 | countersize = COUNTER_OFFSET(repl->nentries) * nr_cpu_ids; |
18bc89aa | 1185 | newinfo = vmalloc(sizeof(*newinfo) + countersize); |
1da177e4 LT |
1186 | ret = -ENOMEM; |
1187 | if (!newinfo) | |
6beceee5 | 1188 | goto free_table; |
1da177e4 | 1189 | |
df07a81e AV |
1190 | p = vmalloc(repl->entries_size); |
1191 | if (!p) | |
1da177e4 LT |
1192 | goto free_newinfo; |
1193 | ||
df07a81e AV |
1194 | memcpy(p, repl->entries, repl->entries_size); |
1195 | newinfo->entries = p; | |
1196 | ||
1197 | newinfo->entries_size = repl->entries_size; | |
1198 | newinfo->nentries = repl->nentries; | |
1da177e4 LT |
1199 | |
1200 | if (countersize) | |
1201 | memset(newinfo->counters, 0, countersize); | |
1202 | ||
1203 | /* fill in newinfo and parse the entries */ | |
1204 | newinfo->chainstack = NULL; | |
df07a81e AV |
1205 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
1206 | if ((repl->valid_hooks & (1 << i)) == 0) | |
1207 | newinfo->hook_entry[i] = NULL; | |
1208 | else | |
1209 | newinfo->hook_entry[i] = p + | |
1210 | ((char *)repl->hook_entry[i] - repl->entries); | |
1211 | } | |
a83d8e8d | 1212 | ret = translate_table(net, repl->name, newinfo); |
1da177e4 LT |
1213 | if (ret != 0) { |
1214 | BUGPRINT("Translate_table failed\n"); | |
1215 | goto free_chainstack; | |
1216 | } | |
1217 | ||
1218 | if (table->check && table->check(newinfo, table->valid_hooks)) { | |
1219 | BUGPRINT("The table doesn't like its own initial data, lol\n"); | |
5189054d JL |
1220 | ret = -EINVAL; |
1221 | goto free_chainstack; | |
1da177e4 LT |
1222 | } |
1223 | ||
1224 | table->private = newinfo; | |
1225 | rwlock_init(&table->lock); | |
7926dbfa | 1226 | mutex_lock(&ebt_mutex); |
511061e2 | 1227 | list_for_each_entry(t, &net->xt.tables[NFPROTO_BRIDGE], list) { |
df0933dc PM |
1228 | if (strcmp(t->name, table->name) == 0) { |
1229 | ret = -EEXIST; | |
1230 | BUGPRINT("Table name already exists\n"); | |
1231 | goto free_unlock; | |
1232 | } | |
1da177e4 LT |
1233 | } |
1234 | ||
1235 | /* Hold a reference count if the chains aren't empty */ | |
1236 | if (newinfo->nentries && !try_module_get(table->me)) { | |
1237 | ret = -ENOENT; | |
1238 | goto free_unlock; | |
1239 | } | |
511061e2 | 1240 | list_add(&table->list, &net->xt.tables[NFPROTO_BRIDGE]); |
57b47a53 | 1241 | mutex_unlock(&ebt_mutex); |
6beceee5 | 1242 | return table; |
1da177e4 | 1243 | free_unlock: |
57b47a53 | 1244 | mutex_unlock(&ebt_mutex); |
1da177e4 LT |
1245 | free_chainstack: |
1246 | if (newinfo->chainstack) { | |
6f912042 | 1247 | for_each_possible_cpu(i) |
1da177e4 LT |
1248 | vfree(newinfo->chainstack[i]); |
1249 | vfree(newinfo->chainstack); | |
1250 | } | |
1251 | vfree(newinfo->entries); | |
1252 | free_newinfo: | |
1253 | vfree(newinfo); | |
6beceee5 AD |
1254 | free_table: |
1255 | kfree(table); | |
1256 | out: | |
1257 | return ERR_PTR(ret); | |
1da177e4 LT |
1258 | } |
1259 | ||
f54e9367 | 1260 | void ebt_unregister_table(struct net *net, struct ebt_table *table) |
1da177e4 LT |
1261 | { |
1262 | int i; | |
1263 | ||
1264 | if (!table) { | |
1265 | BUGPRINT("Request to unregister NULL table!!!\n"); | |
1266 | return; | |
1267 | } | |
57b47a53 | 1268 | mutex_lock(&ebt_mutex); |
df0933dc | 1269 | list_del(&table->list); |
57b47a53 | 1270 | mutex_unlock(&ebt_mutex); |
dbcdf85a | 1271 | EBT_ENTRY_ITERATE(table->private->entries, table->private->entries_size, |
f54e9367 | 1272 | ebt_cleanup_entry, net, NULL); |
dbcdf85a AD |
1273 | if (table->private->nentries) |
1274 | module_put(table->me); | |
68d31872 | 1275 | vfree(table->private->entries); |
1da177e4 | 1276 | if (table->private->chainstack) { |
6f912042 | 1277 | for_each_possible_cpu(i) |
1da177e4 LT |
1278 | vfree(table->private->chainstack[i]); |
1279 | vfree(table->private->chainstack); | |
1280 | } | |
1281 | vfree(table->private); | |
6beceee5 | 1282 | kfree(table); |
1da177e4 LT |
1283 | } |
1284 | ||
1285 | /* userspace just supplied us with counters */ | |
49facff9 FW |
1286 | static int do_update_counters(struct net *net, const char *name, |
1287 | struct ebt_counter __user *counters, | |
1288 | unsigned int num_counters, | |
1289 | const void __user *user, unsigned int len) | |
1da177e4 LT |
1290 | { |
1291 | int i, ret; | |
1292 | struct ebt_counter *tmp; | |
1da177e4 LT |
1293 | struct ebt_table *t; |
1294 | ||
49facff9 | 1295 | if (num_counters == 0) |
1da177e4 LT |
1296 | return -EINVAL; |
1297 | ||
49facff9 FW |
1298 | tmp = vmalloc(num_counters * sizeof(*tmp)); |
1299 | if (!tmp) | |
1da177e4 | 1300 | return -ENOMEM; |
1da177e4 | 1301 | |
49facff9 | 1302 | t = find_table_lock(net, name, &ret, &ebt_mutex); |
1da177e4 LT |
1303 | if (!t) |
1304 | goto free_tmp; | |
1305 | ||
49facff9 | 1306 | if (num_counters != t->private->nentries) { |
1da177e4 LT |
1307 | BUGPRINT("Wrong nr of counters\n"); |
1308 | ret = -EINVAL; | |
1309 | goto unlock_mutex; | |
1310 | } | |
1311 | ||
49facff9 | 1312 | if (copy_from_user(tmp, counters, num_counters * sizeof(*counters))) { |
1da177e4 LT |
1313 | ret = -EFAULT; |
1314 | goto unlock_mutex; | |
1315 | } | |
1316 | ||
1317 | /* we want an atomic add of the counters */ | |
1318 | write_lock_bh(&t->lock); | |
1319 | ||
1320 | /* we add to the counters of the first cpu */ | |
49facff9 | 1321 | for (i = 0; i < num_counters; i++) { |
1da177e4 LT |
1322 | t->private->counters[i].pcnt += tmp[i].pcnt; |
1323 | t->private->counters[i].bcnt += tmp[i].bcnt; | |
1324 | } | |
1325 | ||
1326 | write_unlock_bh(&t->lock); | |
1327 | ret = 0; | |
1328 | unlock_mutex: | |
57b47a53 | 1329 | mutex_unlock(&ebt_mutex); |
1da177e4 LT |
1330 | free_tmp: |
1331 | vfree(tmp); | |
1332 | return ret; | |
1333 | } | |
1334 | ||
49facff9 FW |
1335 | static int update_counters(struct net *net, const void __user *user, |
1336 | unsigned int len) | |
1337 | { | |
1338 | struct ebt_replace hlp; | |
1339 | ||
1340 | if (copy_from_user(&hlp, user, sizeof(hlp))) | |
1341 | return -EFAULT; | |
1342 | ||
1343 | if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter)) | |
1344 | return -EINVAL; | |
1345 | ||
1346 | return do_update_counters(net, hlp.name, hlp.counters, | |
1347 | hlp.num_counters, user, len); | |
1348 | } | |
1349 | ||
d5d1baa1 | 1350 | static inline int ebt_make_matchname(const struct ebt_entry_match *m, |
052a4bc4 | 1351 | const char *base, char __user *ubase) |
1da177e4 | 1352 | { |
1e419cd9 | 1353 | char __user *hlp = ubase + ((char *)m - base); |
848edc69 SN |
1354 | char name[EBT_FUNCTION_MAXNAMELEN] = {}; |
1355 | ||
1356 | /* ebtables expects 32 bytes long names but xt_match names are 29 bytes | |
7f495ad9 IM |
1357 | * long. Copy 29 bytes and fill remaining bytes with zeroes. |
1358 | */ | |
8bc14d25 | 1359 | strlcpy(name, m->u.match->name, sizeof(name)); |
848edc69 | 1360 | if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) |
1da177e4 LT |
1361 | return -EFAULT; |
1362 | return 0; | |
1363 | } | |
1364 | ||
d5d1baa1 | 1365 | static inline int ebt_make_watchername(const struct ebt_entry_watcher *w, |
052a4bc4 | 1366 | const char *base, char __user *ubase) |
1da177e4 | 1367 | { |
1e419cd9 | 1368 | char __user *hlp = ubase + ((char *)w - base); |
848edc69 SN |
1369 | char name[EBT_FUNCTION_MAXNAMELEN] = {}; |
1370 | ||
8bc14d25 | 1371 | strlcpy(name, w->u.watcher->name, sizeof(name)); |
c1bc1d25 | 1372 | if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) |
1da177e4 LT |
1373 | return -EFAULT; |
1374 | return 0; | |
1375 | } | |
1376 | ||
052a4bc4 IM |
1377 | static inline int ebt_make_names(struct ebt_entry *e, const char *base, |
1378 | char __user *ubase) | |
1da177e4 LT |
1379 | { |
1380 | int ret; | |
1e419cd9 | 1381 | char __user *hlp; |
d5d1baa1 | 1382 | const struct ebt_entry_target *t; |
848edc69 | 1383 | char name[EBT_FUNCTION_MAXNAMELEN] = {}; |
1da177e4 | 1384 | |
40642f95 | 1385 | if (e->bitmask == 0) |
1da177e4 LT |
1386 | return 0; |
1387 | ||
1e419cd9 | 1388 | hlp = ubase + (((char *)e + e->target_offset) - base); |
1da177e4 | 1389 | t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
9d6f229f | 1390 | |
1da177e4 LT |
1391 | ret = EBT_MATCH_ITERATE(e, ebt_make_matchname, base, ubase); |
1392 | if (ret != 0) | |
1393 | return ret; | |
1394 | ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase); | |
1395 | if (ret != 0) | |
1396 | return ret; | |
8bc14d25 | 1397 | strlcpy(name, t->u.target->name, sizeof(name)); |
848edc69 | 1398 | if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) |
1da177e4 LT |
1399 | return -EFAULT; |
1400 | return 0; | |
1401 | } | |
1402 | ||
837395aa | 1403 | static int copy_counters_to_user(struct ebt_table *t, |
052a4bc4 IM |
1404 | const struct ebt_counter *oldcounters, |
1405 | void __user *user, unsigned int num_counters, | |
1406 | unsigned int nentries) | |
837395aa FW |
1407 | { |
1408 | struct ebt_counter *counterstmp; | |
1409 | int ret = 0; | |
1410 | ||
1411 | /* userspace might not need the counters */ | |
1412 | if (num_counters == 0) | |
1413 | return 0; | |
1414 | ||
1415 | if (num_counters != nentries) { | |
1416 | BUGPRINT("Num_counters wrong\n"); | |
1417 | return -EINVAL; | |
1418 | } | |
1419 | ||
1420 | counterstmp = vmalloc(nentries * sizeof(*counterstmp)); | |
1421 | if (!counterstmp) | |
1422 | return -ENOMEM; | |
1423 | ||
1424 | write_lock_bh(&t->lock); | |
1425 | get_counters(oldcounters, counterstmp, nentries); | |
1426 | write_unlock_bh(&t->lock); | |
1427 | ||
1428 | if (copy_to_user(user, counterstmp, | |
1429 | nentries * sizeof(struct ebt_counter))) | |
1430 | ret = -EFAULT; | |
1431 | vfree(counterstmp); | |
1432 | return ret; | |
1433 | } | |
1434 | ||
57b47a53 | 1435 | /* called with ebt_mutex locked */ |
1da177e4 | 1436 | static int copy_everything_to_user(struct ebt_table *t, void __user *user, |
052a4bc4 | 1437 | const int *len, int cmd) |
1da177e4 LT |
1438 | { |
1439 | struct ebt_replace tmp; | |
d5d1baa1 | 1440 | const struct ebt_counter *oldcounters; |
1da177e4 | 1441 | unsigned int entries_size, nentries; |
837395aa | 1442 | int ret; |
1da177e4 LT |
1443 | char *entries; |
1444 | ||
1445 | if (cmd == EBT_SO_GET_ENTRIES) { | |
1446 | entries_size = t->private->entries_size; | |
1447 | nentries = t->private->nentries; | |
1448 | entries = t->private->entries; | |
1449 | oldcounters = t->private->counters; | |
1450 | } else { | |
1451 | entries_size = t->table->entries_size; | |
1452 | nentries = t->table->nentries; | |
1453 | entries = t->table->entries; | |
1454 | oldcounters = t->table->counters; | |
1455 | } | |
1456 | ||
90b89af7 | 1457 | if (copy_from_user(&tmp, user, sizeof(tmp))) |
1da177e4 | 1458 | return -EFAULT; |
1da177e4 LT |
1459 | |
1460 | if (*len != sizeof(struct ebt_replace) + entries_size + | |
31a5b837 | 1461 | (tmp.num_counters ? nentries * sizeof(struct ebt_counter) : 0)) |
1da177e4 | 1462 | return -EINVAL; |
1da177e4 LT |
1463 | |
1464 | if (tmp.nentries != nentries) { | |
1465 | BUGPRINT("Nentries wrong\n"); | |
1466 | return -EINVAL; | |
1467 | } | |
1468 | ||
1469 | if (tmp.entries_size != entries_size) { | |
1470 | BUGPRINT("Wrong size\n"); | |
1471 | return -EINVAL; | |
1472 | } | |
1473 | ||
837395aa FW |
1474 | ret = copy_counters_to_user(t, oldcounters, tmp.counters, |
1475 | tmp.num_counters, nentries); | |
1476 | if (ret) | |
1477 | return ret; | |
1da177e4 LT |
1478 | |
1479 | if (copy_to_user(tmp.entries, entries, entries_size)) { | |
1480 | BUGPRINT("Couldn't copy entries to userspace\n"); | |
1481 | return -EFAULT; | |
1482 | } | |
1483 | /* set the match/watcher/target names right */ | |
1484 | return EBT_ENTRY_ITERATE(entries, entries_size, | |
1485 | ebt_make_names, entries, tmp.entries); | |
1486 | } | |
1487 | ||
1488 | static int do_ebt_set_ctl(struct sock *sk, | |
1489 | int cmd, void __user *user, unsigned int len) | |
1490 | { | |
1491 | int ret; | |
bb12b8b2 | 1492 | struct net *net = sock_net(sk); |
1da177e4 | 1493 | |
bb12b8b2 | 1494 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
dce766af FW |
1495 | return -EPERM; |
1496 | ||
31a5b837 | 1497 | switch (cmd) { |
1da177e4 | 1498 | case EBT_SO_SET_ENTRIES: |
bb12b8b2 | 1499 | ret = do_replace(net, user, len); |
1da177e4 LT |
1500 | break; |
1501 | case EBT_SO_SET_COUNTERS: | |
bb12b8b2 | 1502 | ret = update_counters(net, user, len); |
1da177e4 LT |
1503 | break; |
1504 | default: | |
1505 | ret = -EINVAL; | |
81e675c2 | 1506 | } |
1da177e4 LT |
1507 | return ret; |
1508 | } | |
1509 | ||
1510 | static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1511 | { | |
1512 | int ret; | |
1513 | struct ebt_replace tmp; | |
1514 | struct ebt_table *t; | |
bb12b8b2 | 1515 | struct net *net = sock_net(sk); |
1da177e4 | 1516 | |
bb12b8b2 | 1517 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
dce766af FW |
1518 | return -EPERM; |
1519 | ||
1da177e4 LT |
1520 | if (copy_from_user(&tmp, user, sizeof(tmp))) |
1521 | return -EFAULT; | |
1522 | ||
b301f253 PNA |
1523 | tmp.name[sizeof(tmp.name) - 1] = '\0'; |
1524 | ||
bb12b8b2 | 1525 | t = find_table_lock(net, tmp.name, &ret, &ebt_mutex); |
1da177e4 LT |
1526 | if (!t) |
1527 | return ret; | |
1528 | ||
31a5b837 | 1529 | switch (cmd) { |
1da177e4 LT |
1530 | case EBT_SO_GET_INFO: |
1531 | case EBT_SO_GET_INIT_INFO: | |
31a5b837 | 1532 | if (*len != sizeof(struct ebt_replace)) { |
1da177e4 | 1533 | ret = -EINVAL; |
57b47a53 | 1534 | mutex_unlock(&ebt_mutex); |
1da177e4 LT |
1535 | break; |
1536 | } | |
1537 | if (cmd == EBT_SO_GET_INFO) { | |
1538 | tmp.nentries = t->private->nentries; | |
1539 | tmp.entries_size = t->private->entries_size; | |
1540 | tmp.valid_hooks = t->valid_hooks; | |
1541 | } else { | |
1542 | tmp.nentries = t->table->nentries; | |
1543 | tmp.entries_size = t->table->entries_size; | |
1544 | tmp.valid_hooks = t->table->valid_hooks; | |
1545 | } | |
57b47a53 | 1546 | mutex_unlock(&ebt_mutex); |
31a5b837 | 1547 | if (copy_to_user(user, &tmp, *len) != 0) { |
1da177e4 LT |
1548 | BUGPRINT("c2u Didn't work\n"); |
1549 | ret = -EFAULT; | |
1550 | break; | |
1551 | } | |
1552 | ret = 0; | |
1553 | break; | |
1554 | ||
1555 | case EBT_SO_GET_ENTRIES: | |
1556 | case EBT_SO_GET_INIT_ENTRIES: | |
1557 | ret = copy_everything_to_user(t, user, len, cmd); | |
57b47a53 | 1558 | mutex_unlock(&ebt_mutex); |
1da177e4 LT |
1559 | break; |
1560 | ||
1561 | default: | |
57b47a53 | 1562 | mutex_unlock(&ebt_mutex); |
1da177e4 LT |
1563 | ret = -EINVAL; |
1564 | } | |
1565 | ||
1566 | return ret; | |
1567 | } | |
1568 | ||
81e675c2 FW |
1569 | #ifdef CONFIG_COMPAT |
1570 | /* 32 bit-userspace compatibility definitions. */ | |
1571 | struct compat_ebt_replace { | |
1572 | char name[EBT_TABLE_MAXNAMELEN]; | |
1573 | compat_uint_t valid_hooks; | |
1574 | compat_uint_t nentries; | |
1575 | compat_uint_t entries_size; | |
1576 | /* start of the chains */ | |
1577 | compat_uptr_t hook_entry[NF_BR_NUMHOOKS]; | |
1578 | /* nr of counters userspace expects back */ | |
1579 | compat_uint_t num_counters; | |
1580 | /* where the kernel will put the old counters. */ | |
1581 | compat_uptr_t counters; | |
1582 | compat_uptr_t entries; | |
1583 | }; | |
1584 | ||
1585 | /* struct ebt_entry_match, _target and _watcher have same layout */ | |
1586 | struct compat_ebt_entry_mwt { | |
1587 | union { | |
1588 | char name[EBT_FUNCTION_MAXNAMELEN]; | |
1589 | compat_uptr_t ptr; | |
1590 | } u; | |
1591 | compat_uint_t match_size; | |
1592 | compat_uint_t data[0]; | |
1593 | }; | |
1594 | ||
1595 | /* account for possible padding between match_size and ->data */ | |
1596 | static int ebt_compat_entry_padsize(void) | |
1597 | { | |
1598 | BUILD_BUG_ON(XT_ALIGN(sizeof(struct ebt_entry_match)) < | |
1599 | COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt))); | |
1600 | return (int) XT_ALIGN(sizeof(struct ebt_entry_match)) - | |
1601 | COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt)); | |
1602 | } | |
1603 | ||
1604 | static int ebt_compat_match_offset(const struct xt_match *match, | |
1605 | unsigned int userlen) | |
1606 | { | |
7f495ad9 | 1607 | /* ebt_among needs special handling. The kernel .matchsize is |
81e675c2 FW |
1608 | * set to -1 at registration time; at runtime an EBT_ALIGN()ed |
1609 | * value is expected. | |
1610 | * Example: userspace sends 4500, ebt_among.c wants 4504. | |
1611 | */ | |
1612 | if (unlikely(match->matchsize == -1)) | |
1613 | return XT_ALIGN(userlen) - COMPAT_XT_ALIGN(userlen); | |
1614 | return xt_compat_match_offset(match); | |
1615 | } | |
1616 | ||
1617 | static int compat_match_to_user(struct ebt_entry_match *m, void __user **dstptr, | |
1618 | unsigned int *size) | |
1619 | { | |
1620 | const struct xt_match *match = m->u.match; | |
1621 | struct compat_ebt_entry_mwt __user *cm = *dstptr; | |
1622 | int off = ebt_compat_match_offset(match, m->match_size); | |
1623 | compat_uint_t msize = m->match_size - off; | |
1624 | ||
1625 | BUG_ON(off >= m->match_size); | |
1626 | ||
1627 | if (copy_to_user(cm->u.name, match->name, | |
1628 | strlen(match->name) + 1) || put_user(msize, &cm->match_size)) | |
1629 | return -EFAULT; | |
1630 | ||
1631 | if (match->compat_to_user) { | |
1632 | if (match->compat_to_user(cm->data, m->data)) | |
1633 | return -EFAULT; | |
1634 | } else if (copy_to_user(cm->data, m->data, msize)) | |
1635 | return -EFAULT; | |
1636 | ||
1637 | *size -= ebt_compat_entry_padsize() + off; | |
1638 | *dstptr = cm->data; | |
1639 | *dstptr += msize; | |
1640 | return 0; | |
1641 | } | |
1642 | ||
1643 | static int compat_target_to_user(struct ebt_entry_target *t, | |
1644 | void __user **dstptr, | |
1645 | unsigned int *size) | |
1646 | { | |
1647 | const struct xt_target *target = t->u.target; | |
1648 | struct compat_ebt_entry_mwt __user *cm = *dstptr; | |
1649 | int off = xt_compat_target_offset(target); | |
1650 | compat_uint_t tsize = t->target_size - off; | |
1651 | ||
1652 | BUG_ON(off >= t->target_size); | |
1653 | ||
1654 | if (copy_to_user(cm->u.name, target->name, | |
1655 | strlen(target->name) + 1) || put_user(tsize, &cm->match_size)) | |
1656 | return -EFAULT; | |
1657 | ||
1658 | if (target->compat_to_user) { | |
1659 | if (target->compat_to_user(cm->data, t->data)) | |
1660 | return -EFAULT; | |
1661 | } else if (copy_to_user(cm->data, t->data, tsize)) | |
1662 | return -EFAULT; | |
1663 | ||
1664 | *size -= ebt_compat_entry_padsize() + off; | |
1665 | *dstptr = cm->data; | |
1666 | *dstptr += tsize; | |
1667 | return 0; | |
1668 | } | |
1669 | ||
1670 | static int compat_watcher_to_user(struct ebt_entry_watcher *w, | |
1671 | void __user **dstptr, | |
1672 | unsigned int *size) | |
1673 | { | |
1674 | return compat_target_to_user((struct ebt_entry_target *)w, | |
1675 | dstptr, size); | |
1676 | } | |
1677 | ||
1678 | static int compat_copy_entry_to_user(struct ebt_entry *e, void __user **dstptr, | |
1679 | unsigned int *size) | |
1680 | { | |
1681 | struct ebt_entry_target *t; | |
1682 | struct ebt_entry __user *ce; | |
1683 | u32 watchers_offset, target_offset, next_offset; | |
1684 | compat_uint_t origsize; | |
1685 | int ret; | |
1686 | ||
1687 | if (e->bitmask == 0) { | |
1688 | if (*size < sizeof(struct ebt_entries)) | |
1689 | return -EINVAL; | |
1690 | if (copy_to_user(*dstptr, e, sizeof(struct ebt_entries))) | |
1691 | return -EFAULT; | |
1692 | ||
1693 | *dstptr += sizeof(struct ebt_entries); | |
1694 | *size -= sizeof(struct ebt_entries); | |
1695 | return 0; | |
1696 | } | |
1697 | ||
1698 | if (*size < sizeof(*ce)) | |
1699 | return -EINVAL; | |
1700 | ||
1701 | ce = (struct ebt_entry __user *)*dstptr; | |
1702 | if (copy_to_user(ce, e, sizeof(*ce))) | |
1703 | return -EFAULT; | |
1704 | ||
1705 | origsize = *size; | |
1706 | *dstptr += sizeof(*ce); | |
1707 | ||
1708 | ret = EBT_MATCH_ITERATE(e, compat_match_to_user, dstptr, size); | |
1709 | if (ret) | |
1710 | return ret; | |
1711 | watchers_offset = e->watchers_offset - (origsize - *size); | |
1712 | ||
1713 | ret = EBT_WATCHER_ITERATE(e, compat_watcher_to_user, dstptr, size); | |
1714 | if (ret) | |
1715 | return ret; | |
1716 | target_offset = e->target_offset - (origsize - *size); | |
1717 | ||
1718 | t = (struct ebt_entry_target *) ((char *) e + e->target_offset); | |
1719 | ||
1720 | ret = compat_target_to_user(t, dstptr, size); | |
1721 | if (ret) | |
1722 | return ret; | |
1723 | next_offset = e->next_offset - (origsize - *size); | |
1724 | ||
1725 | if (put_user(watchers_offset, &ce->watchers_offset) || | |
1726 | put_user(target_offset, &ce->target_offset) || | |
1727 | put_user(next_offset, &ce->next_offset)) | |
1728 | return -EFAULT; | |
1729 | ||
1730 | *size -= sizeof(*ce); | |
1731 | return 0; | |
1732 | } | |
1733 | ||
1734 | static int compat_calc_match(struct ebt_entry_match *m, int *off) | |
1735 | { | |
1736 | *off += ebt_compat_match_offset(m->u.match, m->match_size); | |
1737 | *off += ebt_compat_entry_padsize(); | |
1738 | return 0; | |
1739 | } | |
1740 | ||
1741 | static int compat_calc_watcher(struct ebt_entry_watcher *w, int *off) | |
1742 | { | |
1743 | *off += xt_compat_target_offset(w->u.watcher); | |
1744 | *off += ebt_compat_entry_padsize(); | |
1745 | return 0; | |
1746 | } | |
1747 | ||
1748 | static int compat_calc_entry(const struct ebt_entry *e, | |
1749 | const struct ebt_table_info *info, | |
1750 | const void *base, | |
1751 | struct compat_ebt_replace *newinfo) | |
1752 | { | |
1753 | const struct ebt_entry_target *t; | |
1754 | unsigned int entry_offset; | |
1755 | int off, ret, i; | |
1756 | ||
1757 | if (e->bitmask == 0) | |
1758 | return 0; | |
1759 | ||
1760 | off = 0; | |
1761 | entry_offset = (void *)e - base; | |
1762 | ||
1763 | EBT_MATCH_ITERATE(e, compat_calc_match, &off); | |
1764 | EBT_WATCHER_ITERATE(e, compat_calc_watcher, &off); | |
1765 | ||
1766 | t = (const struct ebt_entry_target *) ((char *) e + e->target_offset); | |
1767 | ||
1768 | off += xt_compat_target_offset(t->u.target); | |
1769 | off += ebt_compat_entry_padsize(); | |
1770 | ||
1771 | newinfo->entries_size -= off; | |
1772 | ||
1773 | ret = xt_compat_add_offset(NFPROTO_BRIDGE, entry_offset, off); | |
1774 | if (ret) | |
1775 | return ret; | |
1776 | ||
1777 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { | |
1778 | const void *hookptr = info->hook_entry[i]; | |
1779 | if (info->hook_entry[i] && | |
1780 | (e < (struct ebt_entry *)(base - hookptr))) { | |
1781 | newinfo->hook_entry[i] -= off; | |
1782 | pr_debug("0x%08X -> 0x%08X\n", | |
1783 | newinfo->hook_entry[i] + off, | |
1784 | newinfo->hook_entry[i]); | |
1785 | } | |
1786 | } | |
1787 | ||
1788 | return 0; | |
1789 | } | |
1790 | ||
1791 | ||
1792 | static int compat_table_info(const struct ebt_table_info *info, | |
1793 | struct compat_ebt_replace *newinfo) | |
1794 | { | |
1795 | unsigned int size = info->entries_size; | |
1796 | const void *entries = info->entries; | |
1797 | ||
1798 | newinfo->entries_size = size; | |
1799 | ||
5a6351ee | 1800 | xt_compat_init_offsets(NFPROTO_BRIDGE, info->nentries); |
81e675c2 FW |
1801 | return EBT_ENTRY_ITERATE(entries, size, compat_calc_entry, info, |
1802 | entries, newinfo); | |
1803 | } | |
1804 | ||
1805 | static int compat_copy_everything_to_user(struct ebt_table *t, | |
1806 | void __user *user, int *len, int cmd) | |
1807 | { | |
1808 | struct compat_ebt_replace repl, tmp; | |
1809 | struct ebt_counter *oldcounters; | |
1810 | struct ebt_table_info tinfo; | |
1811 | int ret; | |
1812 | void __user *pos; | |
1813 | ||
1814 | memset(&tinfo, 0, sizeof(tinfo)); | |
1815 | ||
1816 | if (cmd == EBT_SO_GET_ENTRIES) { | |
1817 | tinfo.entries_size = t->private->entries_size; | |
1818 | tinfo.nentries = t->private->nentries; | |
1819 | tinfo.entries = t->private->entries; | |
1820 | oldcounters = t->private->counters; | |
1821 | } else { | |
1822 | tinfo.entries_size = t->table->entries_size; | |
1823 | tinfo.nentries = t->table->nentries; | |
1824 | tinfo.entries = t->table->entries; | |
1825 | oldcounters = t->table->counters; | |
1826 | } | |
1827 | ||
1828 | if (copy_from_user(&tmp, user, sizeof(tmp))) | |
1829 | return -EFAULT; | |
1830 | ||
1831 | if (tmp.nentries != tinfo.nentries || | |
1832 | (tmp.num_counters && tmp.num_counters != tinfo.nentries)) | |
1833 | return -EINVAL; | |
1834 | ||
1835 | memcpy(&repl, &tmp, sizeof(repl)); | |
1836 | if (cmd == EBT_SO_GET_ENTRIES) | |
1837 | ret = compat_table_info(t->private, &repl); | |
1838 | else | |
1839 | ret = compat_table_info(&tinfo, &repl); | |
1840 | if (ret) | |
1841 | return ret; | |
1842 | ||
1843 | if (*len != sizeof(tmp) + repl.entries_size + | |
1844 | (tmp.num_counters? tinfo.nentries * sizeof(struct ebt_counter): 0)) { | |
1845 | pr_err("wrong size: *len %d, entries_size %u, replsz %d\n", | |
1846 | *len, tinfo.entries_size, repl.entries_size); | |
1847 | return -EINVAL; | |
1848 | } | |
1849 | ||
1850 | /* userspace might not need the counters */ | |
1851 | ret = copy_counters_to_user(t, oldcounters, compat_ptr(tmp.counters), | |
1852 | tmp.num_counters, tinfo.nentries); | |
1853 | if (ret) | |
1854 | return ret; | |
1855 | ||
1856 | pos = compat_ptr(tmp.entries); | |
1857 | return EBT_ENTRY_ITERATE(tinfo.entries, tinfo.entries_size, | |
1858 | compat_copy_entry_to_user, &pos, &tmp.entries_size); | |
1859 | } | |
1860 | ||
1861 | struct ebt_entries_buf_state { | |
1862 | char *buf_kern_start; /* kernel buffer to copy (translated) data to */ | |
1863 | u32 buf_kern_len; /* total size of kernel buffer */ | |
1864 | u32 buf_kern_offset; /* amount of data copied so far */ | |
1865 | u32 buf_user_offset; /* read position in userspace buffer */ | |
1866 | }; | |
1867 | ||
1868 | static int ebt_buf_count(struct ebt_entries_buf_state *state, unsigned int sz) | |
1869 | { | |
1870 | state->buf_kern_offset += sz; | |
1871 | return state->buf_kern_offset >= sz ? 0 : -EINVAL; | |
1872 | } | |
1873 | ||
1874 | static int ebt_buf_add(struct ebt_entries_buf_state *state, | |
1875 | void *data, unsigned int sz) | |
1876 | { | |
1877 | if (state->buf_kern_start == NULL) | |
1878 | goto count_only; | |
1879 | ||
1880 | BUG_ON(state->buf_kern_offset + sz > state->buf_kern_len); | |
1881 | ||
1882 | memcpy(state->buf_kern_start + state->buf_kern_offset, data, sz); | |
1883 | ||
1884 | count_only: | |
1885 | state->buf_user_offset += sz; | |
1886 | return ebt_buf_count(state, sz); | |
1887 | } | |
1888 | ||
1889 | static int ebt_buf_add_pad(struct ebt_entries_buf_state *state, unsigned int sz) | |
1890 | { | |
1891 | char *b = state->buf_kern_start; | |
1892 | ||
1893 | BUG_ON(b && state->buf_kern_offset > state->buf_kern_len); | |
1894 | ||
1895 | if (b != NULL && sz > 0) | |
1896 | memset(b + state->buf_kern_offset, 0, sz); | |
1897 | /* do not adjust ->buf_user_offset here, we added kernel-side padding */ | |
1898 | return ebt_buf_count(state, sz); | |
1899 | } | |
1900 | ||
1901 | enum compat_mwt { | |
1902 | EBT_COMPAT_MATCH, | |
1903 | EBT_COMPAT_WATCHER, | |
1904 | EBT_COMPAT_TARGET, | |
1905 | }; | |
1906 | ||
1907 | static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt, | |
1908 | enum compat_mwt compat_mwt, | |
1909 | struct ebt_entries_buf_state *state, | |
1910 | const unsigned char *base) | |
1911 | { | |
1912 | char name[EBT_FUNCTION_MAXNAMELEN]; | |
1913 | struct xt_match *match; | |
1914 | struct xt_target *wt; | |
1915 | void *dst = NULL; | |
103a9778 | 1916 | int off, pad = 0; |
97242c85 | 1917 | unsigned int size_kern, match_size = mwt->match_size; |
81e675c2 FW |
1918 | |
1919 | strlcpy(name, mwt->u.name, sizeof(name)); | |
1920 | ||
1921 | if (state->buf_kern_start) | |
1922 | dst = state->buf_kern_start + state->buf_kern_offset; | |
1923 | ||
81e675c2 FW |
1924 | switch (compat_mwt) { |
1925 | case EBT_COMPAT_MATCH: | |
e899b111 | 1926 | match = xt_request_find_match(NFPROTO_BRIDGE, name, 0); |
81e675c2 FW |
1927 | if (IS_ERR(match)) |
1928 | return PTR_ERR(match); | |
1929 | ||
1930 | off = ebt_compat_match_offset(match, match_size); | |
1931 | if (dst) { | |
1932 | if (match->compat_from_user) | |
1933 | match->compat_from_user(dst, mwt->data); | |
1934 | else | |
1935 | memcpy(dst, mwt->data, match_size); | |
1936 | } | |
1937 | ||
1938 | size_kern = match->matchsize; | |
1939 | if (unlikely(size_kern == -1)) | |
1940 | size_kern = match_size; | |
1941 | module_put(match->me); | |
1942 | break; | |
1943 | case EBT_COMPAT_WATCHER: /* fallthrough */ | |
1944 | case EBT_COMPAT_TARGET: | |
e899b111 | 1945 | wt = xt_request_find_target(NFPROTO_BRIDGE, name, 0); |
81e675c2 FW |
1946 | if (IS_ERR(wt)) |
1947 | return PTR_ERR(wt); | |
1948 | off = xt_compat_target_offset(wt); | |
1949 | ||
1950 | if (dst) { | |
1951 | if (wt->compat_from_user) | |
1952 | wt->compat_from_user(dst, mwt->data); | |
1953 | else | |
1954 | memcpy(dst, mwt->data, match_size); | |
1955 | } | |
1956 | ||
1957 | size_kern = wt->targetsize; | |
1958 | module_put(wt->me); | |
1959 | break; | |
97242c85 DM |
1960 | |
1961 | default: | |
1962 | return -EINVAL; | |
81e675c2 FW |
1963 | } |
1964 | ||
81e675c2 FW |
1965 | state->buf_kern_offset += match_size + off; |
1966 | state->buf_user_offset += match_size; | |
1967 | pad = XT_ALIGN(size_kern) - size_kern; | |
1968 | ||
1969 | if (pad > 0 && dst) { | |
1970 | BUG_ON(state->buf_kern_len <= pad); | |
1971 | BUG_ON(state->buf_kern_offset - (match_size + off) + size_kern > state->buf_kern_len - pad); | |
1972 | memset(dst + size_kern, 0, pad); | |
1973 | } | |
1974 | return off + match_size; | |
1975 | } | |
1976 | ||
7f495ad9 | 1977 | /* return size of all matches, watchers or target, including necessary |
81e675c2 FW |
1978 | * alignment and padding. |
1979 | */ | |
1980 | static int ebt_size_mwt(struct compat_ebt_entry_mwt *match32, | |
1981 | unsigned int size_left, enum compat_mwt type, | |
1982 | struct ebt_entries_buf_state *state, const void *base) | |
1983 | { | |
1984 | int growth = 0; | |
1985 | char *buf; | |
1986 | ||
1987 | if (size_left == 0) | |
1988 | return 0; | |
1989 | ||
1990 | buf = (char *) match32; | |
1991 | ||
1992 | while (size_left >= sizeof(*match32)) { | |
1993 | struct ebt_entry_match *match_kern; | |
1994 | int ret; | |
1995 | ||
1996 | match_kern = (struct ebt_entry_match *) state->buf_kern_start; | |
1997 | if (match_kern) { | |
1998 | char *tmp; | |
1999 | tmp = state->buf_kern_start + state->buf_kern_offset; | |
2000 | match_kern = (struct ebt_entry_match *) tmp; | |
2001 | } | |
2002 | ret = ebt_buf_add(state, buf, sizeof(*match32)); | |
2003 | if (ret < 0) | |
2004 | return ret; | |
2005 | size_left -= sizeof(*match32); | |
2006 | ||
2007 | /* add padding before match->data (if any) */ | |
2008 | ret = ebt_buf_add_pad(state, ebt_compat_entry_padsize()); | |
2009 | if (ret < 0) | |
2010 | return ret; | |
2011 | ||
2012 | if (match32->match_size > size_left) | |
2013 | return -EINVAL; | |
2014 | ||
2015 | size_left -= match32->match_size; | |
2016 | ||
2017 | ret = compat_mtw_from_user(match32, type, state, base); | |
2018 | if (ret < 0) | |
2019 | return ret; | |
2020 | ||
2021 | BUG_ON(ret < match32->match_size); | |
2022 | growth += ret - match32->match_size; | |
2023 | growth += ebt_compat_entry_padsize(); | |
2024 | ||
2025 | buf += sizeof(*match32); | |
2026 | buf += match32->match_size; | |
2027 | ||
2028 | if (match_kern) | |
2029 | match_kern->match_size = ret; | |
2030 | ||
2031 | WARN_ON(type == EBT_COMPAT_TARGET && size_left); | |
2032 | match32 = (struct compat_ebt_entry_mwt *) buf; | |
2033 | } | |
2034 | ||
2035 | return growth; | |
2036 | } | |
2037 | ||
81e675c2 FW |
2038 | /* called for all ebt_entry structures. */ |
2039 | static int size_entry_mwt(struct ebt_entry *entry, const unsigned char *base, | |
2040 | unsigned int *total, | |
2041 | struct ebt_entries_buf_state *state) | |
2042 | { | |
2043 | unsigned int i, j, startoff, new_offset = 0; | |
2044 | /* stores match/watchers/targets & offset of next struct ebt_entry: */ | |
2045 | unsigned int offsets[4]; | |
2046 | unsigned int *offsets_update = NULL; | |
2047 | int ret; | |
2048 | char *buf_start; | |
2049 | ||
2050 | if (*total < sizeof(struct ebt_entries)) | |
2051 | return -EINVAL; | |
2052 | ||
2053 | if (!entry->bitmask) { | |
2054 | *total -= sizeof(struct ebt_entries); | |
2055 | return ebt_buf_add(state, entry, sizeof(struct ebt_entries)); | |
2056 | } | |
2057 | if (*total < sizeof(*entry) || entry->next_offset < sizeof(*entry)) | |
2058 | return -EINVAL; | |
2059 | ||
2060 | startoff = state->buf_user_offset; | |
2061 | /* pull in most part of ebt_entry, it does not need to be changed. */ | |
2062 | ret = ebt_buf_add(state, entry, | |
2063 | offsetof(struct ebt_entry, watchers_offset)); | |
2064 | if (ret < 0) | |
2065 | return ret; | |
2066 | ||
2067 | offsets[0] = sizeof(struct ebt_entry); /* matches come first */ | |
2068 | memcpy(&offsets[1], &entry->watchers_offset, | |
2069 | sizeof(offsets) - sizeof(offsets[0])); | |
2070 | ||
2071 | if (state->buf_kern_start) { | |
2072 | buf_start = state->buf_kern_start + state->buf_kern_offset; | |
2073 | offsets_update = (unsigned int *) buf_start; | |
2074 | } | |
2075 | ret = ebt_buf_add(state, &offsets[1], | |
2076 | sizeof(offsets) - sizeof(offsets[0])); | |
2077 | if (ret < 0) | |
2078 | return ret; | |
2079 | buf_start = (char *) entry; | |
7f495ad9 | 2080 | /* 0: matches offset, always follows ebt_entry. |
81e675c2 FW |
2081 | * 1: watchers offset, from ebt_entry structure |
2082 | * 2: target offset, from ebt_entry structure | |
2083 | * 3: next ebt_entry offset, from ebt_entry structure | |
2084 | * | |
2085 | * offsets are relative to beginning of struct ebt_entry (i.e., 0). | |
2086 | */ | |
2087 | for (i = 0, j = 1 ; j < 4 ; j++, i++) { | |
2088 | struct compat_ebt_entry_mwt *match32; | |
2089 | unsigned int size; | |
2090 | char *buf = buf_start; | |
2091 | ||
2092 | buf = buf_start + offsets[i]; | |
2093 | if (offsets[i] > offsets[j]) | |
2094 | return -EINVAL; | |
2095 | ||
2096 | match32 = (struct compat_ebt_entry_mwt *) buf; | |
2097 | size = offsets[j] - offsets[i]; | |
2098 | ret = ebt_size_mwt(match32, size, i, state, base); | |
2099 | if (ret < 0) | |
2100 | return ret; | |
2101 | new_offset += ret; | |
2102 | if (offsets_update && new_offset) { | |
ff67e4e4 | 2103 | pr_debug("change offset %d to %d\n", |
81e675c2 FW |
2104 | offsets_update[i], offsets[j] + new_offset); |
2105 | offsets_update[i] = offsets[j] + new_offset; | |
2106 | } | |
2107 | } | |
2108 | ||
103a9778 FW |
2109 | if (state->buf_kern_start == NULL) { |
2110 | unsigned int offset = buf_start - (char *) base; | |
2111 | ||
2112 | ret = xt_compat_add_offset(NFPROTO_BRIDGE, offset, new_offset); | |
2113 | if (ret < 0) | |
2114 | return ret; | |
2115 | } | |
2116 | ||
81e675c2 FW |
2117 | startoff = state->buf_user_offset - startoff; |
2118 | ||
2119 | BUG_ON(*total < startoff); | |
2120 | *total -= startoff; | |
2121 | return 0; | |
2122 | } | |
2123 | ||
7f495ad9 | 2124 | /* repl->entries_size is the size of the ebt_entry blob in userspace. |
81e675c2 FW |
2125 | * It might need more memory when copied to a 64 bit kernel in case |
2126 | * userspace is 32-bit. So, first task: find out how much memory is needed. | |
2127 | * | |
2128 | * Called before validation is performed. | |
2129 | */ | |
2130 | static int compat_copy_entries(unsigned char *data, unsigned int size_user, | |
2131 | struct ebt_entries_buf_state *state) | |
2132 | { | |
2133 | unsigned int size_remaining = size_user; | |
2134 | int ret; | |
2135 | ||
2136 | ret = EBT_ENTRY_ITERATE(data, size_user, size_entry_mwt, data, | |
2137 | &size_remaining, state); | |
2138 | if (ret < 0) | |
2139 | return ret; | |
2140 | ||
2141 | WARN_ON(size_remaining); | |
2142 | return state->buf_kern_offset; | |
2143 | } | |
2144 | ||
2145 | ||
2146 | static int compat_copy_ebt_replace_from_user(struct ebt_replace *repl, | |
2147 | void __user *user, unsigned int len) | |
2148 | { | |
2149 | struct compat_ebt_replace tmp; | |
2150 | int i; | |
2151 | ||
2152 | if (len < sizeof(tmp)) | |
2153 | return -EINVAL; | |
2154 | ||
2155 | if (copy_from_user(&tmp, user, sizeof(tmp))) | |
2156 | return -EFAULT; | |
2157 | ||
2158 | if (len != sizeof(tmp) + tmp.entries_size) | |
2159 | return -EINVAL; | |
2160 | ||
2161 | if (tmp.entries_size == 0) | |
2162 | return -EINVAL; | |
2163 | ||
2164 | if (tmp.nentries >= ((INT_MAX - sizeof(struct ebt_table_info)) / | |
2165 | NR_CPUS - SMP_CACHE_BYTES) / sizeof(struct ebt_counter)) | |
2166 | return -ENOMEM; | |
2167 | if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter)) | |
2168 | return -ENOMEM; | |
2169 | ||
2170 | memcpy(repl, &tmp, offsetof(struct ebt_replace, hook_entry)); | |
2171 | ||
2172 | /* starting with hook_entry, 32 vs. 64 bit structures are different */ | |
2173 | for (i = 0; i < NF_BR_NUMHOOKS; i++) | |
2174 | repl->hook_entry[i] = compat_ptr(tmp.hook_entry[i]); | |
2175 | ||
2176 | repl->num_counters = tmp.num_counters; | |
2177 | repl->counters = compat_ptr(tmp.counters); | |
2178 | repl->entries = compat_ptr(tmp.entries); | |
2179 | return 0; | |
2180 | } | |
2181 | ||
2182 | static int compat_do_replace(struct net *net, void __user *user, | |
2183 | unsigned int len) | |
2184 | { | |
2185 | int ret, i, countersize, size64; | |
2186 | struct ebt_table_info *newinfo; | |
2187 | struct ebt_replace tmp; | |
2188 | struct ebt_entries_buf_state state; | |
2189 | void *entries_tmp; | |
2190 | ||
2191 | ret = compat_copy_ebt_replace_from_user(&tmp, user, len); | |
90b89af7 FW |
2192 | if (ret) { |
2193 | /* try real handler in case userland supplied needed padding */ | |
2194 | if (ret == -EINVAL && do_replace(net, user, len) == 0) | |
2195 | ret = 0; | |
81e675c2 | 2196 | return ret; |
90b89af7 | 2197 | } |
81e675c2 FW |
2198 | |
2199 | countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids; | |
2200 | newinfo = vmalloc(sizeof(*newinfo) + countersize); | |
2201 | if (!newinfo) | |
2202 | return -ENOMEM; | |
2203 | ||
2204 | if (countersize) | |
2205 | memset(newinfo->counters, 0, countersize); | |
2206 | ||
2207 | memset(&state, 0, sizeof(state)); | |
2208 | ||
2209 | newinfo->entries = vmalloc(tmp.entries_size); | |
2210 | if (!newinfo->entries) { | |
2211 | ret = -ENOMEM; | |
2212 | goto free_newinfo; | |
2213 | } | |
2214 | if (copy_from_user( | |
2215 | newinfo->entries, tmp.entries, tmp.entries_size) != 0) { | |
2216 | ret = -EFAULT; | |
2217 | goto free_entries; | |
2218 | } | |
2219 | ||
2220 | entries_tmp = newinfo->entries; | |
2221 | ||
2222 | xt_compat_lock(NFPROTO_BRIDGE); | |
2223 | ||
5a6351ee | 2224 | xt_compat_init_offsets(NFPROTO_BRIDGE, tmp.nentries); |
81e675c2 FW |
2225 | ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state); |
2226 | if (ret < 0) | |
2227 | goto out_unlock; | |
2228 | ||
2229 | pr_debug("tmp.entries_size %d, kern off %d, user off %d delta %d\n", | |
2230 | tmp.entries_size, state.buf_kern_offset, state.buf_user_offset, | |
2231 | xt_compat_calc_jump(NFPROTO_BRIDGE, tmp.entries_size)); | |
2232 | ||
2233 | size64 = ret; | |
2234 | newinfo->entries = vmalloc(size64); | |
2235 | if (!newinfo->entries) { | |
2236 | vfree(entries_tmp); | |
2237 | ret = -ENOMEM; | |
2238 | goto out_unlock; | |
2239 | } | |
2240 | ||
2241 | memset(&state, 0, sizeof(state)); | |
2242 | state.buf_kern_start = newinfo->entries; | |
2243 | state.buf_kern_len = size64; | |
2244 | ||
2245 | ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state); | |
2246 | BUG_ON(ret < 0); /* parses same data again */ | |
2247 | ||
2248 | vfree(entries_tmp); | |
2249 | tmp.entries_size = size64; | |
2250 | ||
2251 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { | |
2252 | char __user *usrptr; | |
2253 | if (tmp.hook_entry[i]) { | |
2254 | unsigned int delta; | |
2255 | usrptr = (char __user *) tmp.hook_entry[i]; | |
2256 | delta = usrptr - tmp.entries; | |
2257 | usrptr += xt_compat_calc_jump(NFPROTO_BRIDGE, delta); | |
2258 | tmp.hook_entry[i] = (struct ebt_entries __user *)usrptr; | |
2259 | } | |
2260 | } | |
2261 | ||
2262 | xt_compat_flush_offsets(NFPROTO_BRIDGE); | |
2263 | xt_compat_unlock(NFPROTO_BRIDGE); | |
2264 | ||
2265 | ret = do_replace_finish(net, &tmp, newinfo); | |
2266 | if (ret == 0) | |
2267 | return ret; | |
2268 | free_entries: | |
2269 | vfree(newinfo->entries); | |
2270 | free_newinfo: | |
2271 | vfree(newinfo); | |
2272 | return ret; | |
2273 | out_unlock: | |
2274 | xt_compat_flush_offsets(NFPROTO_BRIDGE); | |
2275 | xt_compat_unlock(NFPROTO_BRIDGE); | |
2276 | goto free_entries; | |
2277 | } | |
2278 | ||
2279 | static int compat_update_counters(struct net *net, void __user *user, | |
2280 | unsigned int len) | |
2281 | { | |
2282 | struct compat_ebt_replace hlp; | |
2283 | ||
2284 | if (copy_from_user(&hlp, user, sizeof(hlp))) | |
2285 | return -EFAULT; | |
2286 | ||
90b89af7 | 2287 | /* try real handler in case userland supplied needed padding */ |
81e675c2 | 2288 | if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter)) |
90b89af7 | 2289 | return update_counters(net, user, len); |
81e675c2 FW |
2290 | |
2291 | return do_update_counters(net, hlp.name, compat_ptr(hlp.counters), | |
2292 | hlp.num_counters, user, len); | |
2293 | } | |
2294 | ||
2295 | static int compat_do_ebt_set_ctl(struct sock *sk, | |
2296 | int cmd, void __user *user, unsigned int len) | |
2297 | { | |
2298 | int ret; | |
bb12b8b2 | 2299 | struct net *net = sock_net(sk); |
81e675c2 | 2300 | |
bb12b8b2 | 2301 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
81e675c2 FW |
2302 | return -EPERM; |
2303 | ||
2304 | switch (cmd) { | |
2305 | case EBT_SO_SET_ENTRIES: | |
bb12b8b2 | 2306 | ret = compat_do_replace(net, user, len); |
81e675c2 FW |
2307 | break; |
2308 | case EBT_SO_SET_COUNTERS: | |
bb12b8b2 | 2309 | ret = compat_update_counters(net, user, len); |
81e675c2 FW |
2310 | break; |
2311 | default: | |
2312 | ret = -EINVAL; | |
052a4bc4 | 2313 | } |
81e675c2 FW |
2314 | return ret; |
2315 | } | |
2316 | ||
2317 | static int compat_do_ebt_get_ctl(struct sock *sk, int cmd, | |
2318 | void __user *user, int *len) | |
2319 | { | |
2320 | int ret; | |
2321 | struct compat_ebt_replace tmp; | |
2322 | struct ebt_table *t; | |
bb12b8b2 | 2323 | struct net *net = sock_net(sk); |
81e675c2 | 2324 | |
bb12b8b2 | 2325 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
81e675c2 FW |
2326 | return -EPERM; |
2327 | ||
90b89af7 | 2328 | /* try real handler in case userland supplied needed padding */ |
81e675c2 FW |
2329 | if ((cmd == EBT_SO_GET_INFO || |
2330 | cmd == EBT_SO_GET_INIT_INFO) && *len != sizeof(tmp)) | |
90b89af7 | 2331 | return do_ebt_get_ctl(sk, cmd, user, len); |
81e675c2 FW |
2332 | |
2333 | if (copy_from_user(&tmp, user, sizeof(tmp))) | |
2334 | return -EFAULT; | |
2335 | ||
b301f253 PNA |
2336 | tmp.name[sizeof(tmp.name) - 1] = '\0'; |
2337 | ||
bb12b8b2 | 2338 | t = find_table_lock(net, tmp.name, &ret, &ebt_mutex); |
81e675c2 FW |
2339 | if (!t) |
2340 | return ret; | |
2341 | ||
2342 | xt_compat_lock(NFPROTO_BRIDGE); | |
2343 | switch (cmd) { | |
2344 | case EBT_SO_GET_INFO: | |
2345 | tmp.nentries = t->private->nentries; | |
2346 | ret = compat_table_info(t->private, &tmp); | |
2347 | if (ret) | |
2348 | goto out; | |
2349 | tmp.valid_hooks = t->valid_hooks; | |
2350 | ||
2351 | if (copy_to_user(user, &tmp, *len) != 0) { | |
2352 | ret = -EFAULT; | |
2353 | break; | |
2354 | } | |
2355 | ret = 0; | |
2356 | break; | |
2357 | case EBT_SO_GET_INIT_INFO: | |
2358 | tmp.nentries = t->table->nentries; | |
2359 | tmp.entries_size = t->table->entries_size; | |
2360 | tmp.valid_hooks = t->table->valid_hooks; | |
2361 | ||
2362 | if (copy_to_user(user, &tmp, *len) != 0) { | |
2363 | ret = -EFAULT; | |
2364 | break; | |
2365 | } | |
2366 | ret = 0; | |
2367 | break; | |
2368 | case EBT_SO_GET_ENTRIES: | |
2369 | case EBT_SO_GET_INIT_ENTRIES: | |
7f495ad9 | 2370 | /* try real handler first in case of userland-side padding. |
90b89af7 FW |
2371 | * in case we are dealing with an 'ordinary' 32 bit binary |
2372 | * without 64bit compatibility padding, this will fail right | |
2373 | * after copy_from_user when the *len argument is validated. | |
2374 | * | |
2375 | * the compat_ variant needs to do one pass over the kernel | |
2376 | * data set to adjust for size differences before it the check. | |
2377 | */ | |
2378 | if (copy_everything_to_user(t, user, len, cmd) == 0) | |
2379 | ret = 0; | |
2380 | else | |
2381 | ret = compat_copy_everything_to_user(t, user, len, cmd); | |
81e675c2 FW |
2382 | break; |
2383 | default: | |
2384 | ret = -EINVAL; | |
2385 | } | |
2386 | out: | |
2387 | xt_compat_flush_offsets(NFPROTO_BRIDGE); | |
2388 | xt_compat_unlock(NFPROTO_BRIDGE); | |
2389 | mutex_unlock(&ebt_mutex); | |
2390 | return ret; | |
2391 | } | |
2392 | #endif | |
2393 | ||
97ad8b53 | 2394 | static struct nf_sockopt_ops ebt_sockopts = { |
74ca4e5a AM |
2395 | .pf = PF_INET, |
2396 | .set_optmin = EBT_BASE_CTL, | |
2397 | .set_optmax = EBT_SO_SET_MAX + 1, | |
2398 | .set = do_ebt_set_ctl, | |
81e675c2 FW |
2399 | #ifdef CONFIG_COMPAT |
2400 | .compat_set = compat_do_ebt_set_ctl, | |
2401 | #endif | |
74ca4e5a AM |
2402 | .get_optmin = EBT_BASE_CTL, |
2403 | .get_optmax = EBT_SO_GET_MAX + 1, | |
2404 | .get = do_ebt_get_ctl, | |
81e675c2 FW |
2405 | #ifdef CONFIG_COMPAT |
2406 | .compat_get = compat_do_ebt_get_ctl, | |
2407 | #endif | |
16fcec35 | 2408 | .owner = THIS_MODULE, |
1da177e4 LT |
2409 | }; |
2410 | ||
65b4b4e8 | 2411 | static int __init ebtables_init(void) |
1da177e4 LT |
2412 | { |
2413 | int ret; | |
2414 | ||
043ef46c JE |
2415 | ret = xt_register_target(&ebt_standard_target); |
2416 | if (ret < 0) | |
1da177e4 | 2417 | return ret; |
043ef46c JE |
2418 | ret = nf_register_sockopt(&ebt_sockopts); |
2419 | if (ret < 0) { | |
2420 | xt_unregister_target(&ebt_standard_target); | |
2421 | return ret; | |
2422 | } | |
1da177e4 | 2423 | |
a887c1c1 | 2424 | printk(KERN_INFO "Ebtables v2.0 registered\n"); |
1da177e4 LT |
2425 | return 0; |
2426 | } | |
2427 | ||
65b4b4e8 | 2428 | static void __exit ebtables_fini(void) |
1da177e4 LT |
2429 | { |
2430 | nf_unregister_sockopt(&ebt_sockopts); | |
043ef46c | 2431 | xt_unregister_target(&ebt_standard_target); |
a887c1c1 | 2432 | printk(KERN_INFO "Ebtables v2.0 unregistered\n"); |
1da177e4 LT |
2433 | } |
2434 | ||
2435 | EXPORT_SYMBOL(ebt_register_table); | |
2436 | EXPORT_SYMBOL(ebt_unregister_table); | |
1da177e4 | 2437 | EXPORT_SYMBOL(ebt_do_table); |
65b4b4e8 AM |
2438 | module_init(ebtables_init); |
2439 | module_exit(ebtables_fini); | |
1da177e4 | 2440 | MODULE_LICENSE("GPL"); |