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1da177e4 LT |
1 | /* |
2 | * Handle firewalling | |
3 | * Linux ethernet bridge | |
4 | * | |
5 | * Authors: | |
6 | * Lennert Buytenhek <buytenh@gnu.org> | |
7 | * Bart De Schuymer (maintainer) <bdschuym@pandora.be> | |
8 | * | |
9 | * Changes: | |
10 | * Apr 29 2003: physdev module support (bdschuym) | |
11 | * Jun 19 2003: let arptables see bridged ARP traffic (bdschuym) | |
12 | * Oct 06 2003: filter encapsulated IP/ARP VLAN traffic on untagged bridge | |
13 | * (bdschuym) | |
14 | * Sep 01 2004: add IPv6 filtering (bdschuym) | |
15 | * | |
16 | * This program is free software; you can redistribute it and/or | |
17 | * modify it under the terms of the GNU General Public License | |
18 | * as published by the Free Software Foundation; either version | |
19 | * 2 of the License, or (at your option) any later version. | |
20 | * | |
21 | * Lennert dedicates this file to Kerstin Wurdinger. | |
22 | */ | |
23 | ||
24 | #include <linux/module.h> | |
25 | #include <linux/kernel.h> | |
26 | #include <linux/ip.h> | |
27 | #include <linux/netdevice.h> | |
28 | #include <linux/skbuff.h> | |
29 | #include <linux/if_ether.h> | |
30 | #include <linux/if_vlan.h> | |
31 | #include <linux/netfilter_bridge.h> | |
32 | #include <linux/netfilter_ipv4.h> | |
33 | #include <linux/netfilter_ipv6.h> | |
34 | #include <linux/netfilter_arp.h> | |
35 | #include <linux/in_route.h> | |
36 | #include <net/ip.h> | |
37 | #include <net/ipv6.h> | |
38 | #include <asm/uaccess.h> | |
39 | #include <asm/checksum.h> | |
40 | #include "br_private.h" | |
41 | #ifdef CONFIG_SYSCTL | |
42 | #include <linux/sysctl.h> | |
43 | #endif | |
44 | ||
45 | #define skb_origaddr(skb) (((struct bridge_skb_cb *) \ | |
46 | (skb->nf_bridge->data))->daddr.ipv4) | |
47 | #define store_orig_dstaddr(skb) (skb_origaddr(skb) = (skb)->nh.iph->daddr) | |
48 | #define dnat_took_place(skb) (skb_origaddr(skb) != (skb)->nh.iph->daddr) | |
49 | ||
50 | #define has_bridge_parent(device) ((device)->br_port != NULL) | |
51 | #define bridge_parent(device) ((device)->br_port->br->dev) | |
52 | ||
53 | #ifdef CONFIG_SYSCTL | |
54 | static struct ctl_table_header *brnf_sysctl_header; | |
55 | static int brnf_call_iptables = 1; | |
56 | static int brnf_call_ip6tables = 1; | |
57 | static int brnf_call_arptables = 1; | |
58 | static int brnf_filter_vlan_tagged = 1; | |
59 | #else | |
60 | #define brnf_filter_vlan_tagged 1 | |
61 | #endif | |
62 | ||
63 | #define IS_VLAN_IP (skb->protocol == __constant_htons(ETH_P_8021Q) && \ | |
64 | hdr->h_vlan_encapsulated_proto == __constant_htons(ETH_P_IP) && \ | |
65 | brnf_filter_vlan_tagged) | |
66 | #define IS_VLAN_IPV6 (skb->protocol == __constant_htons(ETH_P_8021Q) && \ | |
67 | hdr->h_vlan_encapsulated_proto == __constant_htons(ETH_P_IPV6) && \ | |
68 | brnf_filter_vlan_tagged) | |
69 | #define IS_VLAN_ARP (skb->protocol == __constant_htons(ETH_P_8021Q) && \ | |
70 | hdr->h_vlan_encapsulated_proto == __constant_htons(ETH_P_ARP) && \ | |
71 | brnf_filter_vlan_tagged) | |
72 | ||
73 | /* We need these fake structures to make netfilter happy -- | |
74 | * lots of places assume that skb->dst != NULL, which isn't | |
75 | * all that unreasonable. | |
76 | * | |
77 | * Currently, we fill in the PMTU entry because netfilter | |
78 | * refragmentation needs it, and the rt_flags entry because | |
79 | * ipt_REJECT needs it. Future netfilter modules might | |
80 | * require us to fill additional fields. */ | |
81 | static struct net_device __fake_net_device = { | |
82 | .hard_header_len = ETH_HLEN | |
83 | }; | |
84 | ||
85 | static struct rtable __fake_rtable = { | |
86 | .u = { | |
87 | .dst = { | |
88 | .__refcnt = ATOMIC_INIT(1), | |
89 | .dev = &__fake_net_device, | |
90 | .path = &__fake_rtable.u.dst, | |
91 | .metrics = {[RTAX_MTU - 1] = 1500}, | |
92 | } | |
93 | }, | |
94 | .rt_flags = 0, | |
95 | }; | |
96 | ||
97 | ||
98 | /* PF_BRIDGE/PRE_ROUTING *********************************************/ | |
99 | /* Undo the changes made for ip6tables PREROUTING and continue the | |
100 | * bridge PRE_ROUTING hook. */ | |
101 | static int br_nf_pre_routing_finish_ipv6(struct sk_buff *skb) | |
102 | { | |
103 | struct nf_bridge_info *nf_bridge = skb->nf_bridge; | |
104 | ||
1da177e4 LT |
105 | if (nf_bridge->mask & BRNF_PKT_TYPE) { |
106 | skb->pkt_type = PACKET_OTHERHOST; | |
107 | nf_bridge->mask ^= BRNF_PKT_TYPE; | |
108 | } | |
109 | nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING; | |
110 | ||
111 | skb->dst = (struct dst_entry *)&__fake_rtable; | |
112 | dst_hold(skb->dst); | |
113 | ||
114 | skb->dev = nf_bridge->physindev; | |
115 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
116 | skb_push(skb, VLAN_HLEN); | |
117 | skb->nh.raw -= VLAN_HLEN; | |
118 | } | |
119 | NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL, | |
120 | br_handle_frame_finish, 1); | |
121 | ||
122 | return 0; | |
123 | } | |
124 | ||
125 | static void __br_dnat_complain(void) | |
126 | { | |
127 | static unsigned long last_complaint; | |
128 | ||
129 | if (jiffies - last_complaint >= 5 * HZ) { | |
130 | printk(KERN_WARNING "Performing cross-bridge DNAT requires IP " | |
131 | "forwarding to be enabled\n"); | |
132 | last_complaint = jiffies; | |
133 | } | |
134 | } | |
135 | ||
136 | /* This requires some explaining. If DNAT has taken place, | |
137 | * we will need to fix up the destination Ethernet address, | |
138 | * and this is a tricky process. | |
139 | * | |
140 | * There are two cases to consider: | |
141 | * 1. The packet was DNAT'ed to a device in the same bridge | |
142 | * port group as it was received on. We can still bridge | |
143 | * the packet. | |
144 | * 2. The packet was DNAT'ed to a different device, either | |
145 | * a non-bridged device or another bridge port group. | |
146 | * The packet will need to be routed. | |
147 | * | |
148 | * The correct way of distinguishing between these two cases is to | |
149 | * call ip_route_input() and to look at skb->dst->dev, which is | |
150 | * changed to the destination device if ip_route_input() succeeds. | |
151 | * | |
152 | * Let us first consider the case that ip_route_input() succeeds: | |
153 | * | |
154 | * If skb->dst->dev equals the logical bridge device the packet | |
155 | * came in on, we can consider this bridging. We then call | |
156 | * skb->dst->output() which will make the packet enter br_nf_local_out() | |
157 | * not much later. In that function it is assured that the iptables | |
158 | * FORWARD chain is traversed for the packet. | |
159 | * | |
160 | * Otherwise, the packet is considered to be routed and we just | |
161 | * change the destination MAC address so that the packet will | |
162 | * later be passed up to the IP stack to be routed. | |
163 | * | |
164 | * Let us now consider the case that ip_route_input() fails: | |
165 | * | |
166 | * After a "echo '0' > /proc/sys/net/ipv4/ip_forward" ip_route_input() | |
167 | * will fail, while __ip_route_output_key() will return success. The source | |
168 | * address for __ip_route_output_key() is set to zero, so __ip_route_output_key | |
169 | * thinks we're handling a locally generated packet and won't care | |
170 | * if IP forwarding is allowed. We send a warning message to the users's | |
171 | * log telling her to put IP forwarding on. | |
172 | * | |
173 | * ip_route_input() will also fail if there is no route available. | |
174 | * In that case we just drop the packet. | |
175 | * | |
176 | * --Lennert, 20020411 | |
177 | * --Bart, 20020416 (updated) | |
178 | * --Bart, 20021007 (updated) */ | |
179 | static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb) | |
180 | { | |
1da177e4 LT |
181 | if (skb->pkt_type == PACKET_OTHERHOST) { |
182 | skb->pkt_type = PACKET_HOST; | |
183 | skb->nf_bridge->mask |= BRNF_PKT_TYPE; | |
184 | } | |
185 | skb->nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING; | |
186 | ||
187 | skb->dev = bridge_parent(skb->dev); | |
188 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
189 | skb_pull(skb, VLAN_HLEN); | |
190 | skb->nh.raw += VLAN_HLEN; | |
191 | } | |
192 | skb->dst->output(skb); | |
193 | return 0; | |
194 | } | |
195 | ||
196 | static int br_nf_pre_routing_finish(struct sk_buff *skb) | |
197 | { | |
198 | struct net_device *dev = skb->dev; | |
199 | struct iphdr *iph = skb->nh.iph; | |
200 | struct nf_bridge_info *nf_bridge = skb->nf_bridge; | |
201 | ||
1da177e4 LT |
202 | if (nf_bridge->mask & BRNF_PKT_TYPE) { |
203 | skb->pkt_type = PACKET_OTHERHOST; | |
204 | nf_bridge->mask ^= BRNF_PKT_TYPE; | |
205 | } | |
206 | nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING; | |
207 | ||
208 | if (dnat_took_place(skb)) { | |
209 | if (ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, | |
210 | dev)) { | |
211 | struct rtable *rt; | |
212 | struct flowi fl = { .nl_u = | |
213 | { .ip4_u = { .daddr = iph->daddr, .saddr = 0 , | |
214 | .tos = RT_TOS(iph->tos)} }, .proto = 0}; | |
215 | ||
216 | if (!ip_route_output_key(&rt, &fl)) { | |
1c011bed BDS |
217 | /* - Bridged-and-DNAT'ed traffic doesn't |
218 | * require ip_forwarding. | |
219 | * - Deal with redirected traffic. */ | |
220 | if (((struct dst_entry *)rt)->dev == dev || | |
221 | rt->rt_type == RTN_LOCAL) { | |
1da177e4 LT |
222 | skb->dst = (struct dst_entry *)rt; |
223 | goto bridged_dnat; | |
224 | } | |
225 | __br_dnat_complain(); | |
226 | dst_release((struct dst_entry *)rt); | |
227 | } | |
228 | kfree_skb(skb); | |
229 | return 0; | |
230 | } else { | |
231 | if (skb->dst->dev == dev) { | |
232 | bridged_dnat: | |
233 | /* Tell br_nf_local_out this is a | |
234 | * bridged frame */ | |
235 | nf_bridge->mask |= BRNF_BRIDGED_DNAT; | |
236 | skb->dev = nf_bridge->physindev; | |
237 | if (skb->protocol == | |
238 | __constant_htons(ETH_P_8021Q)) { | |
239 | skb_push(skb, VLAN_HLEN); | |
240 | skb->nh.raw -= VLAN_HLEN; | |
241 | } | |
242 | NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, | |
243 | skb, skb->dev, NULL, | |
244 | br_nf_pre_routing_finish_bridge, | |
245 | 1); | |
246 | return 0; | |
247 | } | |
248 | memcpy(eth_hdr(skb)->h_dest, dev->dev_addr, | |
249 | ETH_ALEN); | |
250 | skb->pkt_type = PACKET_HOST; | |
251 | } | |
252 | } else { | |
253 | skb->dst = (struct dst_entry *)&__fake_rtable; | |
254 | dst_hold(skb->dst); | |
255 | } | |
256 | ||
257 | skb->dev = nf_bridge->physindev; | |
258 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
259 | skb_push(skb, VLAN_HLEN); | |
260 | skb->nh.raw -= VLAN_HLEN; | |
261 | } | |
262 | NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL, | |
263 | br_handle_frame_finish, 1); | |
264 | ||
265 | return 0; | |
266 | } | |
267 | ||
268 | /* Some common code for IPv4/IPv6 */ | |
269 | static void setup_pre_routing(struct sk_buff *skb) | |
270 | { | |
271 | struct nf_bridge_info *nf_bridge = skb->nf_bridge; | |
272 | ||
273 | if (skb->pkt_type == PACKET_OTHERHOST) { | |
274 | skb->pkt_type = PACKET_HOST; | |
275 | nf_bridge->mask |= BRNF_PKT_TYPE; | |
276 | } | |
277 | ||
278 | nf_bridge->mask |= BRNF_NF_BRIDGE_PREROUTING; | |
279 | nf_bridge->physindev = skb->dev; | |
280 | skb->dev = bridge_parent(skb->dev); | |
281 | } | |
282 | ||
283 | /* We only check the length. A bridge shouldn't do any hop-by-hop stuff anyway */ | |
284 | static int check_hbh_len(struct sk_buff *skb) | |
285 | { | |
286 | unsigned char *raw = (u8*)(skb->nh.ipv6h+1); | |
287 | u32 pkt_len; | |
288 | int off = raw - skb->nh.raw; | |
289 | int len = (raw[1]+1)<<3; | |
290 | ||
291 | if ((raw + len) - skb->data > skb_headlen(skb)) | |
292 | goto bad; | |
293 | ||
294 | off += 2; | |
295 | len -= 2; | |
296 | ||
297 | while (len > 0) { | |
298 | int optlen = raw[off+1]+2; | |
299 | ||
300 | switch (skb->nh.raw[off]) { | |
301 | case IPV6_TLV_PAD0: | |
302 | optlen = 1; | |
303 | break; | |
304 | ||
305 | case IPV6_TLV_PADN: | |
306 | break; | |
307 | ||
308 | case IPV6_TLV_JUMBO: | |
309 | if (skb->nh.raw[off+1] != 4 || (off&3) != 2) | |
310 | goto bad; | |
311 | ||
312 | pkt_len = ntohl(*(u32*)(skb->nh.raw+off+2)); | |
313 | ||
314 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) | |
315 | goto bad; | |
316 | if (pkt_len + sizeof(struct ipv6hdr) < skb->len) { | |
317 | if (__pskb_trim(skb, | |
318 | pkt_len + sizeof(struct ipv6hdr))) | |
319 | goto bad; | |
320 | if (skb->ip_summed == CHECKSUM_HW) | |
321 | skb->ip_summed = CHECKSUM_NONE; | |
322 | } | |
323 | break; | |
324 | default: | |
325 | if (optlen > len) | |
326 | goto bad; | |
327 | break; | |
328 | } | |
329 | off += optlen; | |
330 | len -= optlen; | |
331 | } | |
332 | if (len == 0) | |
333 | return 0; | |
334 | bad: | |
335 | return -1; | |
336 | ||
337 | } | |
338 | ||
339 | /* Replicate the checks that IPv6 does on packet reception and pass the packet | |
340 | * to ip6tables, which doesn't support NAT, so things are fairly simple. */ | |
341 | static unsigned int br_nf_pre_routing_ipv6(unsigned int hook, | |
342 | struct sk_buff *skb, const struct net_device *in, | |
343 | const struct net_device *out, int (*okfn)(struct sk_buff *)) | |
344 | { | |
345 | struct ipv6hdr *hdr; | |
346 | u32 pkt_len; | |
347 | struct nf_bridge_info *nf_bridge; | |
348 | ||
349 | if (skb->len < sizeof(struct ipv6hdr)) | |
350 | goto inhdr_error; | |
351 | ||
352 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) | |
353 | goto inhdr_error; | |
354 | ||
355 | hdr = skb->nh.ipv6h; | |
356 | ||
357 | if (hdr->version != 6) | |
358 | goto inhdr_error; | |
359 | ||
360 | pkt_len = ntohs(hdr->payload_len); | |
361 | ||
362 | if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { | |
363 | if (pkt_len + sizeof(struct ipv6hdr) > skb->len) | |
364 | goto inhdr_error; | |
365 | if (pkt_len + sizeof(struct ipv6hdr) < skb->len) { | |
366 | if (__pskb_trim(skb, pkt_len + sizeof(struct ipv6hdr))) | |
367 | goto inhdr_error; | |
368 | if (skb->ip_summed == CHECKSUM_HW) | |
369 | skb->ip_summed = CHECKSUM_NONE; | |
370 | } | |
371 | } | |
372 | if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb)) | |
373 | goto inhdr_error; | |
374 | ||
1da177e4 LT |
375 | if ((nf_bridge = nf_bridge_alloc(skb)) == NULL) |
376 | return NF_DROP; | |
377 | setup_pre_routing(skb); | |
378 | ||
379 | NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL, | |
380 | br_nf_pre_routing_finish_ipv6); | |
381 | ||
382 | return NF_STOLEN; | |
383 | ||
384 | inhdr_error: | |
385 | return NF_DROP; | |
386 | } | |
387 | ||
388 | /* Direct IPv6 traffic to br_nf_pre_routing_ipv6. | |
389 | * Replicate the checks that IPv4 does on packet reception. | |
390 | * Set skb->dev to the bridge device (i.e. parent of the | |
391 | * receiving device) to make netfilter happy, the REDIRECT | |
392 | * target in particular. Save the original destination IP | |
393 | * address to be able to detect DNAT afterwards. */ | |
394 | static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb, | |
395 | const struct net_device *in, const struct net_device *out, | |
396 | int (*okfn)(struct sk_buff *)) | |
397 | { | |
398 | struct iphdr *iph; | |
399 | __u32 len; | |
400 | struct sk_buff *skb = *pskb; | |
401 | struct nf_bridge_info *nf_bridge; | |
402 | struct vlan_ethhdr *hdr = vlan_eth_hdr(*pskb); | |
403 | ||
404 | if (skb->protocol == __constant_htons(ETH_P_IPV6) || IS_VLAN_IPV6) { | |
405 | #ifdef CONFIG_SYSCTL | |
406 | if (!brnf_call_ip6tables) | |
407 | return NF_ACCEPT; | |
408 | #endif | |
409 | if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL) | |
410 | goto out; | |
411 | ||
412 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
413 | skb_pull(skb, VLAN_HLEN); | |
414 | (skb)->nh.raw += VLAN_HLEN; | |
415 | } | |
416 | return br_nf_pre_routing_ipv6(hook, skb, in, out, okfn); | |
417 | } | |
418 | #ifdef CONFIG_SYSCTL | |
419 | if (!brnf_call_iptables) | |
420 | return NF_ACCEPT; | |
421 | #endif | |
422 | ||
423 | if (skb->protocol != __constant_htons(ETH_P_IP) && !IS_VLAN_IP) | |
424 | return NF_ACCEPT; | |
425 | ||
426 | if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL) | |
427 | goto out; | |
428 | ||
429 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
430 | skb_pull(skb, VLAN_HLEN); | |
431 | (skb)->nh.raw += VLAN_HLEN; | |
432 | } | |
433 | ||
434 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
435 | goto inhdr_error; | |
436 | ||
437 | iph = skb->nh.iph; | |
438 | if (iph->ihl < 5 || iph->version != 4) | |
439 | goto inhdr_error; | |
440 | ||
441 | if (!pskb_may_pull(skb, 4*iph->ihl)) | |
442 | goto inhdr_error; | |
443 | ||
444 | iph = skb->nh.iph; | |
445 | if (ip_fast_csum((__u8 *)iph, iph->ihl) != 0) | |
446 | goto inhdr_error; | |
447 | ||
448 | len = ntohs(iph->tot_len); | |
449 | if (skb->len < len || len < 4*iph->ihl) | |
450 | goto inhdr_error; | |
451 | ||
452 | if (skb->len > len) { | |
453 | __pskb_trim(skb, len); | |
454 | if (skb->ip_summed == CHECKSUM_HW) | |
455 | skb->ip_summed = CHECKSUM_NONE; | |
456 | } | |
457 | ||
1da177e4 LT |
458 | if ((nf_bridge = nf_bridge_alloc(skb)) == NULL) |
459 | return NF_DROP; | |
460 | setup_pre_routing(skb); | |
461 | store_orig_dstaddr(skb); | |
462 | ||
463 | NF_HOOK(PF_INET, NF_IP_PRE_ROUTING, skb, skb->dev, NULL, | |
464 | br_nf_pre_routing_finish); | |
465 | ||
466 | return NF_STOLEN; | |
467 | ||
468 | inhdr_error: | |
469 | // IP_INC_STATS_BH(IpInHdrErrors); | |
470 | out: | |
471 | return NF_DROP; | |
472 | } | |
473 | ||
474 | ||
475 | /* PF_BRIDGE/LOCAL_IN ************************************************/ | |
476 | /* The packet is locally destined, which requires a real | |
477 | * dst_entry, so detach the fake one. On the way up, the | |
478 | * packet would pass through PRE_ROUTING again (which already | |
479 | * took place when the packet entered the bridge), but we | |
480 | * register an IPv4 PRE_ROUTING 'sabotage' hook that will | |
481 | * prevent this from happening. */ | |
482 | static unsigned int br_nf_local_in(unsigned int hook, struct sk_buff **pskb, | |
483 | const struct net_device *in, const struct net_device *out, | |
484 | int (*okfn)(struct sk_buff *)) | |
485 | { | |
486 | struct sk_buff *skb = *pskb; | |
487 | ||
488 | if (skb->dst == (struct dst_entry *)&__fake_rtable) { | |
489 | dst_release(skb->dst); | |
490 | skb->dst = NULL; | |
491 | } | |
492 | ||
493 | return NF_ACCEPT; | |
494 | } | |
495 | ||
496 | ||
497 | /* PF_BRIDGE/FORWARD *************************************************/ | |
498 | static int br_nf_forward_finish(struct sk_buff *skb) | |
499 | { | |
500 | struct nf_bridge_info *nf_bridge = skb->nf_bridge; | |
501 | struct net_device *in; | |
502 | struct vlan_ethhdr *hdr = vlan_eth_hdr(skb); | |
503 | ||
1da177e4 LT |
504 | if (skb->protocol != __constant_htons(ETH_P_ARP) && !IS_VLAN_ARP) { |
505 | in = nf_bridge->physindev; | |
506 | if (nf_bridge->mask & BRNF_PKT_TYPE) { | |
507 | skb->pkt_type = PACKET_OTHERHOST; | |
508 | nf_bridge->mask ^= BRNF_PKT_TYPE; | |
509 | } | |
510 | } else { | |
511 | in = *((struct net_device **)(skb->cb)); | |
512 | } | |
513 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
514 | skb_push(skb, VLAN_HLEN); | |
515 | skb->nh.raw -= VLAN_HLEN; | |
516 | } | |
517 | NF_HOOK_THRESH(PF_BRIDGE, NF_BR_FORWARD, skb, in, | |
518 | skb->dev, br_forward_finish, 1); | |
519 | return 0; | |
520 | } | |
521 | ||
522 | /* This is the 'purely bridged' case. For IP, we pass the packet to | |
523 | * netfilter with indev and outdev set to the bridge device, | |
524 | * but we are still able to filter on the 'real' indev/outdev | |
525 | * because of the physdev module. For ARP, indev and outdev are the | |
526 | * bridge ports. */ | |
527 | static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb, | |
528 | const struct net_device *in, const struct net_device *out, | |
529 | int (*okfn)(struct sk_buff *)) | |
530 | { | |
531 | struct sk_buff *skb = *pskb; | |
532 | struct nf_bridge_info *nf_bridge; | |
533 | struct vlan_ethhdr *hdr = vlan_eth_hdr(skb); | |
534 | int pf; | |
535 | ||
536 | if (!skb->nf_bridge) | |
537 | return NF_ACCEPT; | |
538 | ||
539 | if (skb->protocol == __constant_htons(ETH_P_IP) || IS_VLAN_IP) | |
540 | pf = PF_INET; | |
541 | else | |
542 | pf = PF_INET6; | |
543 | ||
544 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
545 | skb_pull(*pskb, VLAN_HLEN); | |
546 | (*pskb)->nh.raw += VLAN_HLEN; | |
547 | } | |
548 | ||
1da177e4 LT |
549 | nf_bridge = skb->nf_bridge; |
550 | if (skb->pkt_type == PACKET_OTHERHOST) { | |
551 | skb->pkt_type = PACKET_HOST; | |
552 | nf_bridge->mask |= BRNF_PKT_TYPE; | |
553 | } | |
554 | ||
555 | /* The physdev module checks on this */ | |
556 | nf_bridge->mask |= BRNF_BRIDGED; | |
557 | nf_bridge->physoutdev = skb->dev; | |
558 | ||
559 | NF_HOOK(pf, NF_IP_FORWARD, skb, bridge_parent(in), | |
560 | bridge_parent(out), br_nf_forward_finish); | |
561 | ||
562 | return NF_STOLEN; | |
563 | } | |
564 | ||
565 | static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff **pskb, | |
566 | const struct net_device *in, const struct net_device *out, | |
567 | int (*okfn)(struct sk_buff *)) | |
568 | { | |
569 | struct sk_buff *skb = *pskb; | |
570 | struct vlan_ethhdr *hdr = vlan_eth_hdr(skb); | |
571 | struct net_device **d = (struct net_device **)(skb->cb); | |
572 | ||
573 | #ifdef CONFIG_SYSCTL | |
574 | if (!brnf_call_arptables) | |
575 | return NF_ACCEPT; | |
576 | #endif | |
577 | ||
578 | if (skb->protocol != __constant_htons(ETH_P_ARP)) { | |
579 | if (!IS_VLAN_ARP) | |
580 | return NF_ACCEPT; | |
581 | skb_pull(*pskb, VLAN_HLEN); | |
582 | (*pskb)->nh.raw += VLAN_HLEN; | |
583 | } | |
584 | ||
1da177e4 LT |
585 | if (skb->nh.arph->ar_pln != 4) { |
586 | if (IS_VLAN_ARP) { | |
587 | skb_push(*pskb, VLAN_HLEN); | |
588 | (*pskb)->nh.raw -= VLAN_HLEN; | |
589 | } | |
590 | return NF_ACCEPT; | |
591 | } | |
592 | *d = (struct net_device *)in; | |
593 | NF_HOOK(NF_ARP, NF_ARP_FORWARD, skb, (struct net_device *)in, | |
594 | (struct net_device *)out, br_nf_forward_finish); | |
595 | ||
596 | return NF_STOLEN; | |
597 | } | |
598 | ||
599 | ||
600 | /* PF_BRIDGE/LOCAL_OUT ***********************************************/ | |
601 | static int br_nf_local_out_finish(struct sk_buff *skb) | |
602 | { | |
1da177e4 LT |
603 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { |
604 | skb_push(skb, VLAN_HLEN); | |
605 | skb->nh.raw -= VLAN_HLEN; | |
606 | } | |
607 | ||
608 | NF_HOOK_THRESH(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev, | |
609 | br_forward_finish, NF_BR_PRI_FIRST + 1); | |
610 | ||
611 | return 0; | |
612 | } | |
613 | ||
614 | /* This function sees both locally originated IP packets and forwarded | |
615 | * IP packets (in both cases the destination device is a bridge | |
616 | * device). It also sees bridged-and-DNAT'ed packets. | |
617 | * To be able to filter on the physical bridge devices (with the physdev | |
618 | * module), we steal packets destined to a bridge device away from the | |
619 | * PF_INET/FORWARD and PF_INET/OUTPUT hook functions, and give them back later, | |
620 | * when we have determined the real output device. This is done in here. | |
621 | * | |
622 | * If (nf_bridge->mask & BRNF_BRIDGED_DNAT) then the packet is bridged | |
623 | * and we fake the PF_BRIDGE/FORWARD hook. The function br_nf_forward() | |
624 | * will then fake the PF_INET/FORWARD hook. br_nf_local_out() has priority | |
625 | * NF_BR_PRI_FIRST, so no relevant PF_BRIDGE/INPUT functions have been nor | |
626 | * will be executed. | |
627 | * Otherwise, if nf_bridge->physindev is NULL, the bridge-nf code never touched | |
628 | * this packet before, and so the packet was locally originated. We fake | |
629 | * the PF_INET/LOCAL_OUT hook. | |
630 | * Finally, if nf_bridge->physindev isn't NULL, then the packet was IP routed, | |
631 | * so we fake the PF_INET/FORWARD hook. ip_sabotage_out() makes sure | |
632 | * even routed packets that didn't arrive on a bridge interface have their | |
633 | * nf_bridge->physindev set. */ | |
634 | static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff **pskb, | |
635 | const struct net_device *in, const struct net_device *out, | |
636 | int (*okfn)(struct sk_buff *)) | |
637 | { | |
638 | struct net_device *realindev, *realoutdev; | |
639 | struct sk_buff *skb = *pskb; | |
640 | struct nf_bridge_info *nf_bridge; | |
641 | struct vlan_ethhdr *hdr = vlan_eth_hdr(skb); | |
642 | int pf; | |
643 | ||
644 | if (!skb->nf_bridge) | |
645 | return NF_ACCEPT; | |
646 | ||
647 | if (skb->protocol == __constant_htons(ETH_P_IP) || IS_VLAN_IP) | |
648 | pf = PF_INET; | |
649 | else | |
650 | pf = PF_INET6; | |
651 | ||
652 | #ifdef CONFIG_NETFILTER_DEBUG | |
653 | /* Sometimes we get packets with NULL ->dst here (for example, | |
654 | * running a dhcp client daemon triggers this). This should now | |
655 | * be fixed, but let's keep the check around. */ | |
656 | if (skb->dst == NULL) { | |
657 | printk(KERN_CRIT "br_netfilter: skb->dst == NULL."); | |
658 | return NF_ACCEPT; | |
659 | } | |
660 | #endif | |
661 | ||
662 | nf_bridge = skb->nf_bridge; | |
663 | nf_bridge->physoutdev = skb->dev; | |
664 | realindev = nf_bridge->physindev; | |
665 | ||
666 | /* Bridged, take PF_BRIDGE/FORWARD. | |
667 | * (see big note in front of br_nf_pre_routing_finish) */ | |
668 | if (nf_bridge->mask & BRNF_BRIDGED_DNAT) { | |
669 | if (nf_bridge->mask & BRNF_PKT_TYPE) { | |
670 | skb->pkt_type = PACKET_OTHERHOST; | |
671 | nf_bridge->mask ^= BRNF_PKT_TYPE; | |
672 | } | |
673 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
674 | skb_push(skb, VLAN_HLEN); | |
675 | skb->nh.raw -= VLAN_HLEN; | |
676 | } | |
677 | ||
678 | NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, realindev, | |
679 | skb->dev, br_forward_finish); | |
680 | goto out; | |
681 | } | |
682 | realoutdev = bridge_parent(skb->dev); | |
683 | ||
684 | #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) | |
685 | /* iptables should match -o br0.x */ | |
686 | if (nf_bridge->netoutdev) | |
687 | realoutdev = nf_bridge->netoutdev; | |
688 | #endif | |
689 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
690 | skb_pull(skb, VLAN_HLEN); | |
691 | (*pskb)->nh.raw += VLAN_HLEN; | |
692 | } | |
693 | /* IP forwarded traffic has a physindev, locally | |
694 | * generated traffic hasn't. */ | |
695 | if (realindev != NULL) { | |
696 | if (!(nf_bridge->mask & BRNF_DONT_TAKE_PARENT) && | |
697 | has_bridge_parent(realindev)) | |
698 | realindev = bridge_parent(realindev); | |
699 | ||
700 | NF_HOOK_THRESH(pf, NF_IP_FORWARD, skb, realindev, | |
701 | realoutdev, br_nf_local_out_finish, | |
702 | NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD + 1); | |
703 | } else { | |
1da177e4 LT |
704 | NF_HOOK_THRESH(pf, NF_IP_LOCAL_OUT, skb, realindev, |
705 | realoutdev, br_nf_local_out_finish, | |
706 | NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT + 1); | |
707 | } | |
708 | ||
709 | out: | |
710 | return NF_STOLEN; | |
711 | } | |
712 | ||
713 | ||
714 | /* PF_BRIDGE/POST_ROUTING ********************************************/ | |
715 | static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb, | |
716 | const struct net_device *in, const struct net_device *out, | |
717 | int (*okfn)(struct sk_buff *)) | |
718 | { | |
719 | struct sk_buff *skb = *pskb; | |
720 | struct nf_bridge_info *nf_bridge = (*pskb)->nf_bridge; | |
721 | struct vlan_ethhdr *hdr = vlan_eth_hdr(skb); | |
722 | struct net_device *realoutdev = bridge_parent(skb->dev); | |
723 | int pf; | |
724 | ||
725 | #ifdef CONFIG_NETFILTER_DEBUG | |
726 | /* Be very paranoid. This probably won't happen anymore, but let's | |
727 | * keep the check just to be sure... */ | |
728 | if (skb->mac.raw < skb->head || skb->mac.raw + ETH_HLEN > skb->data) { | |
729 | printk(KERN_CRIT "br_netfilter: Argh!! br_nf_post_routing: " | |
730 | "bad mac.raw pointer."); | |
731 | goto print_error; | |
732 | } | |
733 | #endif | |
734 | ||
735 | if (!nf_bridge) | |
736 | return NF_ACCEPT; | |
737 | ||
738 | if (skb->protocol == __constant_htons(ETH_P_IP) || IS_VLAN_IP) | |
739 | pf = PF_INET; | |
740 | else | |
741 | pf = PF_INET6; | |
742 | ||
743 | #ifdef CONFIG_NETFILTER_DEBUG | |
744 | if (skb->dst == NULL) { | |
745 | printk(KERN_CRIT "br_netfilter: skb->dst == NULL."); | |
746 | goto print_error; | |
747 | } | |
1da177e4 LT |
748 | #endif |
749 | ||
750 | /* We assume any code from br_dev_queue_push_xmit onwards doesn't care | |
751 | * about the value of skb->pkt_type. */ | |
752 | if (skb->pkt_type == PACKET_OTHERHOST) { | |
753 | skb->pkt_type = PACKET_HOST; | |
754 | nf_bridge->mask |= BRNF_PKT_TYPE; | |
755 | } | |
756 | ||
757 | if (skb->protocol == __constant_htons(ETH_P_8021Q)) { | |
758 | skb_pull(skb, VLAN_HLEN); | |
759 | skb->nh.raw += VLAN_HLEN; | |
760 | } | |
761 | ||
762 | nf_bridge_save_header(skb); | |
763 | ||
764 | #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) | |
765 | if (nf_bridge->netoutdev) | |
766 | realoutdev = nf_bridge->netoutdev; | |
767 | #endif | |
768 | NF_HOOK(pf, NF_IP_POST_ROUTING, skb, NULL, realoutdev, | |
769 | br_dev_queue_push_xmit); | |
770 | ||
771 | return NF_STOLEN; | |
772 | ||
773 | #ifdef CONFIG_NETFILTER_DEBUG | |
774 | print_error: | |
775 | if (skb->dev != NULL) { | |
776 | printk("[%s]", skb->dev->name); | |
777 | if (has_bridge_parent(skb->dev)) | |
778 | printk("[%s]", bridge_parent(skb->dev)->name); | |
779 | } | |
780 | printk(" head:%p, raw:%p, data:%p\n", skb->head, skb->mac.raw, | |
781 | skb->data); | |
782 | return NF_ACCEPT; | |
783 | #endif | |
784 | } | |
785 | ||
786 | ||
787 | /* IP/SABOTAGE *****************************************************/ | |
788 | /* Don't hand locally destined packets to PF_INET(6)/PRE_ROUTING | |
789 | * for the second time. */ | |
790 | static unsigned int ip_sabotage_in(unsigned int hook, struct sk_buff **pskb, | |
791 | const struct net_device *in, const struct net_device *out, | |
792 | int (*okfn)(struct sk_buff *)) | |
793 | { | |
794 | if ((*pskb)->nf_bridge && | |
795 | !((*pskb)->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)) { | |
796 | return NF_STOP; | |
797 | } | |
798 | ||
799 | return NF_ACCEPT; | |
800 | } | |
801 | ||
802 | /* Postpone execution of PF_INET(6)/FORWARD, PF_INET(6)/LOCAL_OUT | |
803 | * and PF_INET(6)/POST_ROUTING until we have done the forwarding | |
804 | * decision in the bridge code and have determined nf_bridge->physoutdev. */ | |
805 | static unsigned int ip_sabotage_out(unsigned int hook, struct sk_buff **pskb, | |
806 | const struct net_device *in, const struct net_device *out, | |
807 | int (*okfn)(struct sk_buff *)) | |
808 | { | |
809 | struct sk_buff *skb = *pskb; | |
810 | ||
811 | if ((out->hard_start_xmit == br_dev_xmit && | |
812 | okfn != br_nf_forward_finish && | |
813 | okfn != br_nf_local_out_finish && | |
814 | okfn != br_dev_queue_push_xmit) | |
815 | #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) | |
816 | || ((out->priv_flags & IFF_802_1Q_VLAN) && | |
817 | VLAN_DEV_INFO(out)->real_dev->hard_start_xmit == br_dev_xmit) | |
818 | #endif | |
819 | ) { | |
820 | struct nf_bridge_info *nf_bridge; | |
821 | ||
822 | if (!skb->nf_bridge) { | |
823 | #ifdef CONFIG_SYSCTL | |
824 | /* This code is executed while in the IP(v6) stack, | |
825 | the version should be 4 or 6. We can't use | |
826 | skb->protocol because that isn't set on | |
827 | PF_INET(6)/LOCAL_OUT. */ | |
828 | struct iphdr *ip = skb->nh.iph; | |
829 | ||
830 | if (ip->version == 4 && !brnf_call_iptables) | |
831 | return NF_ACCEPT; | |
832 | else if (ip->version == 6 && !brnf_call_ip6tables) | |
833 | return NF_ACCEPT; | |
834 | #endif | |
835 | if (hook == NF_IP_POST_ROUTING) | |
836 | return NF_ACCEPT; | |
837 | if (!nf_bridge_alloc(skb)) | |
838 | return NF_DROP; | |
839 | } | |
840 | ||
841 | nf_bridge = skb->nf_bridge; | |
842 | ||
843 | /* This frame will arrive on PF_BRIDGE/LOCAL_OUT and we | |
844 | * will need the indev then. For a brouter, the real indev | |
845 | * can be a bridge port, so we make sure br_nf_local_out() | |
846 | * doesn't use the bridge parent of the indev by using | |
847 | * the BRNF_DONT_TAKE_PARENT mask. */ | |
848 | if (hook == NF_IP_FORWARD && nf_bridge->physindev == NULL) { | |
9666dae5 | 849 | nf_bridge->mask |= BRNF_DONT_TAKE_PARENT; |
1da177e4 LT |
850 | nf_bridge->physindev = (struct net_device *)in; |
851 | } | |
852 | #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) | |
853 | /* the iptables outdev is br0.x, not br0 */ | |
854 | if (out->priv_flags & IFF_802_1Q_VLAN) | |
855 | nf_bridge->netoutdev = (struct net_device *)out; | |
856 | #endif | |
857 | return NF_STOP; | |
858 | } | |
859 | ||
860 | return NF_ACCEPT; | |
861 | } | |
862 | ||
863 | /* For br_nf_local_out we need (prio = NF_BR_PRI_FIRST), to insure that innocent | |
864 | * PF_BRIDGE/NF_BR_LOCAL_OUT functions don't get bridged traffic as input. | |
865 | * For br_nf_post_routing, we need (prio = NF_BR_PRI_LAST), because | |
866 | * ip_refrag() can return NF_STOLEN. */ | |
867 | static struct nf_hook_ops br_nf_ops[] = { | |
868 | { .hook = br_nf_pre_routing, | |
869 | .owner = THIS_MODULE, | |
870 | .pf = PF_BRIDGE, | |
871 | .hooknum = NF_BR_PRE_ROUTING, | |
872 | .priority = NF_BR_PRI_BRNF, }, | |
873 | { .hook = br_nf_local_in, | |
874 | .owner = THIS_MODULE, | |
875 | .pf = PF_BRIDGE, | |
876 | .hooknum = NF_BR_LOCAL_IN, | |
877 | .priority = NF_BR_PRI_BRNF, }, | |
878 | { .hook = br_nf_forward_ip, | |
879 | .owner = THIS_MODULE, | |
880 | .pf = PF_BRIDGE, | |
881 | .hooknum = NF_BR_FORWARD, | |
882 | .priority = NF_BR_PRI_BRNF - 1, }, | |
883 | { .hook = br_nf_forward_arp, | |
884 | .owner = THIS_MODULE, | |
885 | .pf = PF_BRIDGE, | |
886 | .hooknum = NF_BR_FORWARD, | |
887 | .priority = NF_BR_PRI_BRNF, }, | |
888 | { .hook = br_nf_local_out, | |
889 | .owner = THIS_MODULE, | |
890 | .pf = PF_BRIDGE, | |
891 | .hooknum = NF_BR_LOCAL_OUT, | |
892 | .priority = NF_BR_PRI_FIRST, }, | |
893 | { .hook = br_nf_post_routing, | |
894 | .owner = THIS_MODULE, | |
895 | .pf = PF_BRIDGE, | |
896 | .hooknum = NF_BR_POST_ROUTING, | |
897 | .priority = NF_BR_PRI_LAST, }, | |
898 | { .hook = ip_sabotage_in, | |
899 | .owner = THIS_MODULE, | |
900 | .pf = PF_INET, | |
901 | .hooknum = NF_IP_PRE_ROUTING, | |
902 | .priority = NF_IP_PRI_FIRST, }, | |
903 | { .hook = ip_sabotage_in, | |
904 | .owner = THIS_MODULE, | |
905 | .pf = PF_INET6, | |
906 | .hooknum = NF_IP6_PRE_ROUTING, | |
907 | .priority = NF_IP6_PRI_FIRST, }, | |
908 | { .hook = ip_sabotage_out, | |
909 | .owner = THIS_MODULE, | |
910 | .pf = PF_INET, | |
911 | .hooknum = NF_IP_FORWARD, | |
912 | .priority = NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD, }, | |
913 | { .hook = ip_sabotage_out, | |
914 | .owner = THIS_MODULE, | |
915 | .pf = PF_INET6, | |
916 | .hooknum = NF_IP6_FORWARD, | |
917 | .priority = NF_IP6_PRI_BRIDGE_SABOTAGE_FORWARD, }, | |
918 | { .hook = ip_sabotage_out, | |
919 | .owner = THIS_MODULE, | |
920 | .pf = PF_INET, | |
921 | .hooknum = NF_IP_LOCAL_OUT, | |
922 | .priority = NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT, }, | |
923 | { .hook = ip_sabotage_out, | |
924 | .owner = THIS_MODULE, | |
925 | .pf = PF_INET6, | |
926 | .hooknum = NF_IP6_LOCAL_OUT, | |
927 | .priority = NF_IP6_PRI_BRIDGE_SABOTAGE_LOCAL_OUT, }, | |
928 | { .hook = ip_sabotage_out, | |
929 | .owner = THIS_MODULE, | |
930 | .pf = PF_INET, | |
931 | .hooknum = NF_IP_POST_ROUTING, | |
932 | .priority = NF_IP_PRI_FIRST, }, | |
933 | { .hook = ip_sabotage_out, | |
934 | .owner = THIS_MODULE, | |
935 | .pf = PF_INET6, | |
936 | .hooknum = NF_IP6_POST_ROUTING, | |
937 | .priority = NF_IP6_PRI_FIRST, }, | |
938 | }; | |
939 | ||
940 | #ifdef CONFIG_SYSCTL | |
941 | static | |
942 | int brnf_sysctl_call_tables(ctl_table *ctl, int write, struct file * filp, | |
943 | void __user *buffer, size_t *lenp, loff_t *ppos) | |
944 | { | |
945 | int ret; | |
946 | ||
947 | ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos); | |
948 | ||
949 | if (write && *(int *)(ctl->data)) | |
950 | *(int *)(ctl->data) = 1; | |
951 | return ret; | |
952 | } | |
953 | ||
954 | static ctl_table brnf_table[] = { | |
955 | { | |
956 | .ctl_name = NET_BRIDGE_NF_CALL_ARPTABLES, | |
957 | .procname = "bridge-nf-call-arptables", | |
958 | .data = &brnf_call_arptables, | |
959 | .maxlen = sizeof(int), | |
960 | .mode = 0644, | |
961 | .proc_handler = &brnf_sysctl_call_tables, | |
962 | }, | |
963 | { | |
964 | .ctl_name = NET_BRIDGE_NF_CALL_IPTABLES, | |
965 | .procname = "bridge-nf-call-iptables", | |
966 | .data = &brnf_call_iptables, | |
967 | .maxlen = sizeof(int), | |
968 | .mode = 0644, | |
969 | .proc_handler = &brnf_sysctl_call_tables, | |
970 | }, | |
971 | { | |
972 | .ctl_name = NET_BRIDGE_NF_CALL_IP6TABLES, | |
973 | .procname = "bridge-nf-call-ip6tables", | |
974 | .data = &brnf_call_ip6tables, | |
975 | .maxlen = sizeof(int), | |
976 | .mode = 0644, | |
977 | .proc_handler = &brnf_sysctl_call_tables, | |
978 | }, | |
979 | { | |
980 | .ctl_name = NET_BRIDGE_NF_FILTER_VLAN_TAGGED, | |
981 | .procname = "bridge-nf-filter-vlan-tagged", | |
982 | .data = &brnf_filter_vlan_tagged, | |
983 | .maxlen = sizeof(int), | |
984 | .mode = 0644, | |
985 | .proc_handler = &brnf_sysctl_call_tables, | |
986 | }, | |
987 | { .ctl_name = 0 } | |
988 | }; | |
989 | ||
990 | static ctl_table brnf_bridge_table[] = { | |
991 | { | |
992 | .ctl_name = NET_BRIDGE, | |
993 | .procname = "bridge", | |
994 | .mode = 0555, | |
995 | .child = brnf_table, | |
996 | }, | |
997 | { .ctl_name = 0 } | |
998 | }; | |
999 | ||
1000 | static ctl_table brnf_net_table[] = { | |
1001 | { | |
1002 | .ctl_name = CTL_NET, | |
1003 | .procname = "net", | |
1004 | .mode = 0555, | |
1005 | .child = brnf_bridge_table, | |
1006 | }, | |
1007 | { .ctl_name = 0 } | |
1008 | }; | |
1009 | #endif | |
1010 | ||
1011 | int br_netfilter_init(void) | |
1012 | { | |
1013 | int i; | |
1014 | ||
1015 | for (i = 0; i < ARRAY_SIZE(br_nf_ops); i++) { | |
1016 | int ret; | |
1017 | ||
1018 | if ((ret = nf_register_hook(&br_nf_ops[i])) >= 0) | |
1019 | continue; | |
1020 | ||
1021 | while (i--) | |
1022 | nf_unregister_hook(&br_nf_ops[i]); | |
1023 | ||
1024 | return ret; | |
1025 | } | |
1026 | ||
1027 | #ifdef CONFIG_SYSCTL | |
1028 | brnf_sysctl_header = register_sysctl_table(brnf_net_table, 0); | |
1029 | if (brnf_sysctl_header == NULL) { | |
1030 | printk(KERN_WARNING "br_netfilter: can't register to sysctl.\n"); | |
1031 | for (i = 0; i < ARRAY_SIZE(br_nf_ops); i++) | |
1032 | nf_unregister_hook(&br_nf_ops[i]); | |
1033 | return -EFAULT; | |
1034 | } | |
1035 | #endif | |
1036 | ||
1037 | printk(KERN_NOTICE "Bridge firewalling registered\n"); | |
1038 | ||
1039 | return 0; | |
1040 | } | |
1041 | ||
1042 | void br_netfilter_fini(void) | |
1043 | { | |
1044 | int i; | |
1045 | ||
1046 | for (i = ARRAY_SIZE(br_nf_ops) - 1; i >= 0; i--) | |
1047 | nf_unregister_hook(&br_nf_ops[i]); | |
1048 | #ifdef CONFIG_SYSCTL | |
1049 | unregister_sysctl_table(brnf_sysctl_header); | |
1050 | #endif | |
1051 | } |