Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * This is a module which is used for queueing IPv4 packets and | |
3 | * communicating with userspace via netlink. | |
4 | * | |
5 | * (C) 2000-2002 James Morris <jmorris@intercode.com.au> | |
9bb7bc94 | 6 | * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org> |
1da177e4 LT |
7 | * |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | * | |
12 | * 2000-03-27: Simplified code (thanks to Andi Kleen for clues). | |
13 | * 2000-05-20: Fixed notifier problems (following Miguel Freitas' report). | |
14 | * 2000-06-19: Fixed so nfmark is copied to metadata (reported by Sebastian | |
15 | * Zander). | |
16 | * 2000-08-01: Added Nick Williams' MAC support. | |
17 | * 2002-06-25: Code cleanup. | |
18 | * 2005-01-10: Added /proc counter for dropped packets; fixed so | |
19 | * packets aren't delivered to user space if they're going | |
20 | * to be dropped. | |
9bb7bc94 | 21 | * 2005-05-26: local_bh_{disable,enable} around nf_reinject (Harald Welte) |
1da177e4 LT |
22 | * |
23 | */ | |
24 | #include <linux/module.h> | |
25 | #include <linux/skbuff.h> | |
26 | #include <linux/init.h> | |
27 | #include <linux/ip.h> | |
28 | #include <linux/notifier.h> | |
29 | #include <linux/netdevice.h> | |
30 | #include <linux/netfilter.h> | |
31 | #include <linux/netfilter_ipv4/ip_queue.h> | |
32 | #include <linux/netfilter_ipv4/ip_tables.h> | |
33 | #include <linux/netlink.h> | |
34 | #include <linux/spinlock.h> | |
35 | #include <linux/sysctl.h> | |
36 | #include <linux/proc_fs.h> | |
37 | #include <linux/security.h> | |
38 | #include <net/sock.h> | |
39 | #include <net/route.h> | |
40 | ||
41 | #define IPQ_QMAX_DEFAULT 1024 | |
42 | #define IPQ_PROC_FS_NAME "ip_queue" | |
43 | #define NET_IPQ_QMAX 2088 | |
44 | #define NET_IPQ_QMAX_NAME "ip_queue_maxlen" | |
45 | ||
46 | struct ipq_rt_info { | |
47 | __u8 tos; | |
48 | __u32 daddr; | |
49 | __u32 saddr; | |
50 | }; | |
51 | ||
52 | struct ipq_queue_entry { | |
53 | struct list_head list; | |
54 | struct nf_info *info; | |
55 | struct sk_buff *skb; | |
56 | struct ipq_rt_info rt_info; | |
57 | }; | |
58 | ||
59 | typedef int (*ipq_cmpfn)(struct ipq_queue_entry *, unsigned long); | |
60 | ||
61 | static unsigned char copy_mode = IPQ_COPY_NONE; | |
62 | static unsigned int queue_maxlen = IPQ_QMAX_DEFAULT; | |
63 | static DEFINE_RWLOCK(queue_lock); | |
64 | static int peer_pid; | |
65 | static unsigned int copy_range; | |
66 | static unsigned int queue_total; | |
67 | static unsigned int queue_dropped = 0; | |
68 | static unsigned int queue_user_dropped = 0; | |
69 | static struct sock *ipqnl; | |
70 | static LIST_HEAD(queue_list); | |
71 | static DECLARE_MUTEX(ipqnl_sem); | |
72 | ||
73 | static void | |
74 | ipq_issue_verdict(struct ipq_queue_entry *entry, int verdict) | |
75 | { | |
9bb7bc94 HW |
76 | /* TCP input path (and probably other bits) assume to be called |
77 | * from softirq context, not from syscall, like ipq_issue_verdict is | |
78 | * called. TCP input path deadlocks with locks taken from timer | |
79 | * softirq, e.g. We therefore emulate this by local_bh_disable() */ | |
80 | ||
81 | local_bh_disable(); | |
1da177e4 | 82 | nf_reinject(entry->skb, entry->info, verdict); |
9bb7bc94 HW |
83 | local_bh_enable(); |
84 | ||
1da177e4 LT |
85 | kfree(entry); |
86 | } | |
87 | ||
88 | static inline void | |
89 | __ipq_enqueue_entry(struct ipq_queue_entry *entry) | |
90 | { | |
91 | list_add(&entry->list, &queue_list); | |
92 | queue_total++; | |
93 | } | |
94 | ||
95 | /* | |
96 | * Find and return a queued entry matched by cmpfn, or return the last | |
97 | * entry if cmpfn is NULL. | |
98 | */ | |
99 | static inline struct ipq_queue_entry * | |
100 | __ipq_find_entry(ipq_cmpfn cmpfn, unsigned long data) | |
101 | { | |
102 | struct list_head *p; | |
103 | ||
104 | list_for_each_prev(p, &queue_list) { | |
105 | struct ipq_queue_entry *entry = (struct ipq_queue_entry *)p; | |
106 | ||
107 | if (!cmpfn || cmpfn(entry, data)) | |
108 | return entry; | |
109 | } | |
110 | return NULL; | |
111 | } | |
112 | ||
113 | static inline void | |
114 | __ipq_dequeue_entry(struct ipq_queue_entry *entry) | |
115 | { | |
116 | list_del(&entry->list); | |
117 | queue_total--; | |
118 | } | |
119 | ||
120 | static inline struct ipq_queue_entry * | |
121 | __ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data) | |
122 | { | |
123 | struct ipq_queue_entry *entry; | |
124 | ||
125 | entry = __ipq_find_entry(cmpfn, data); | |
126 | if (entry == NULL) | |
127 | return NULL; | |
128 | ||
129 | __ipq_dequeue_entry(entry); | |
130 | return entry; | |
131 | } | |
132 | ||
133 | ||
134 | static inline void | |
135 | __ipq_flush(int verdict) | |
136 | { | |
137 | struct ipq_queue_entry *entry; | |
138 | ||
139 | while ((entry = __ipq_find_dequeue_entry(NULL, 0))) | |
140 | ipq_issue_verdict(entry, verdict); | |
141 | } | |
142 | ||
143 | static inline int | |
144 | __ipq_set_mode(unsigned char mode, unsigned int range) | |
145 | { | |
146 | int status = 0; | |
147 | ||
148 | switch(mode) { | |
149 | case IPQ_COPY_NONE: | |
150 | case IPQ_COPY_META: | |
151 | copy_mode = mode; | |
152 | copy_range = 0; | |
153 | break; | |
154 | ||
155 | case IPQ_COPY_PACKET: | |
156 | copy_mode = mode; | |
157 | copy_range = range; | |
158 | if (copy_range > 0xFFFF) | |
159 | copy_range = 0xFFFF; | |
160 | break; | |
161 | ||
162 | default: | |
163 | status = -EINVAL; | |
164 | ||
165 | } | |
166 | return status; | |
167 | } | |
168 | ||
169 | static inline void | |
170 | __ipq_reset(void) | |
171 | { | |
172 | peer_pid = 0; | |
173 | net_disable_timestamp(); | |
174 | __ipq_set_mode(IPQ_COPY_NONE, 0); | |
175 | __ipq_flush(NF_DROP); | |
176 | } | |
177 | ||
178 | static struct ipq_queue_entry * | |
179 | ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data) | |
180 | { | |
181 | struct ipq_queue_entry *entry; | |
182 | ||
183 | write_lock_bh(&queue_lock); | |
184 | entry = __ipq_find_dequeue_entry(cmpfn, data); | |
185 | write_unlock_bh(&queue_lock); | |
186 | return entry; | |
187 | } | |
188 | ||
189 | static void | |
190 | ipq_flush(int verdict) | |
191 | { | |
192 | write_lock_bh(&queue_lock); | |
193 | __ipq_flush(verdict); | |
194 | write_unlock_bh(&queue_lock); | |
195 | } | |
196 | ||
197 | static struct sk_buff * | |
198 | ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp) | |
199 | { | |
200 | unsigned char *old_tail; | |
201 | size_t size = 0; | |
202 | size_t data_len = 0; | |
203 | struct sk_buff *skb; | |
204 | struct ipq_packet_msg *pmsg; | |
205 | struct nlmsghdr *nlh; | |
206 | ||
207 | read_lock_bh(&queue_lock); | |
208 | ||
209 | switch (copy_mode) { | |
210 | case IPQ_COPY_META: | |
211 | case IPQ_COPY_NONE: | |
212 | size = NLMSG_SPACE(sizeof(*pmsg)); | |
213 | data_len = 0; | |
214 | break; | |
215 | ||
216 | case IPQ_COPY_PACKET: | |
217 | if (copy_range == 0 || copy_range > entry->skb->len) | |
218 | data_len = entry->skb->len; | |
219 | else | |
220 | data_len = copy_range; | |
221 | ||
222 | size = NLMSG_SPACE(sizeof(*pmsg) + data_len); | |
223 | break; | |
224 | ||
225 | default: | |
226 | *errp = -EINVAL; | |
227 | read_unlock_bh(&queue_lock); | |
228 | return NULL; | |
229 | } | |
230 | ||
231 | read_unlock_bh(&queue_lock); | |
232 | ||
233 | skb = alloc_skb(size, GFP_ATOMIC); | |
234 | if (!skb) | |
235 | goto nlmsg_failure; | |
236 | ||
237 | old_tail= skb->tail; | |
238 | nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh)); | |
239 | pmsg = NLMSG_DATA(nlh); | |
240 | memset(pmsg, 0, sizeof(*pmsg)); | |
241 | ||
242 | pmsg->packet_id = (unsigned long )entry; | |
243 | pmsg->data_len = data_len; | |
244 | pmsg->timestamp_sec = entry->skb->stamp.tv_sec; | |
245 | pmsg->timestamp_usec = entry->skb->stamp.tv_usec; | |
246 | pmsg->mark = entry->skb->nfmark; | |
247 | pmsg->hook = entry->info->hook; | |
248 | pmsg->hw_protocol = entry->skb->protocol; | |
249 | ||
250 | if (entry->info->indev) | |
251 | strcpy(pmsg->indev_name, entry->info->indev->name); | |
252 | else | |
253 | pmsg->indev_name[0] = '\0'; | |
254 | ||
255 | if (entry->info->outdev) | |
256 | strcpy(pmsg->outdev_name, entry->info->outdev->name); | |
257 | else | |
258 | pmsg->outdev_name[0] = '\0'; | |
259 | ||
260 | if (entry->info->indev && entry->skb->dev) { | |
261 | pmsg->hw_type = entry->skb->dev->type; | |
262 | if (entry->skb->dev->hard_header_parse) | |
263 | pmsg->hw_addrlen = | |
264 | entry->skb->dev->hard_header_parse(entry->skb, | |
265 | pmsg->hw_addr); | |
266 | } | |
267 | ||
268 | if (data_len) | |
269 | if (skb_copy_bits(entry->skb, 0, pmsg->payload, data_len)) | |
270 | BUG(); | |
271 | ||
272 | nlh->nlmsg_len = skb->tail - old_tail; | |
273 | return skb; | |
274 | ||
275 | nlmsg_failure: | |
276 | if (skb) | |
277 | kfree_skb(skb); | |
278 | *errp = -EINVAL; | |
279 | printk(KERN_ERR "ip_queue: error creating packet message\n"); | |
280 | return NULL; | |
281 | } | |
282 | ||
283 | static int | |
284 | ipq_enqueue_packet(struct sk_buff *skb, struct nf_info *info, void *data) | |
285 | { | |
286 | int status = -EINVAL; | |
287 | struct sk_buff *nskb; | |
288 | struct ipq_queue_entry *entry; | |
289 | ||
290 | if (copy_mode == IPQ_COPY_NONE) | |
291 | return -EAGAIN; | |
292 | ||
293 | entry = kmalloc(sizeof(*entry), GFP_ATOMIC); | |
294 | if (entry == NULL) { | |
295 | printk(KERN_ERR "ip_queue: OOM in ipq_enqueue_packet()\n"); | |
296 | return -ENOMEM; | |
297 | } | |
298 | ||
299 | entry->info = info; | |
300 | entry->skb = skb; | |
301 | ||
302 | if (entry->info->hook == NF_IP_LOCAL_OUT) { | |
303 | struct iphdr *iph = skb->nh.iph; | |
304 | ||
305 | entry->rt_info.tos = iph->tos; | |
306 | entry->rt_info.daddr = iph->daddr; | |
307 | entry->rt_info.saddr = iph->saddr; | |
308 | } | |
309 | ||
310 | nskb = ipq_build_packet_message(entry, &status); | |
311 | if (nskb == NULL) | |
312 | goto err_out_free; | |
313 | ||
314 | write_lock_bh(&queue_lock); | |
315 | ||
316 | if (!peer_pid) | |
317 | goto err_out_free_nskb; | |
318 | ||
319 | if (queue_total >= queue_maxlen) { | |
320 | queue_dropped++; | |
321 | status = -ENOSPC; | |
322 | if (net_ratelimit()) | |
323 | printk (KERN_WARNING "ip_queue: full at %d entries, " | |
324 | "dropping packets(s). Dropped: %d\n", queue_total, | |
325 | queue_dropped); | |
326 | goto err_out_free_nskb; | |
327 | } | |
328 | ||
329 | /* netlink_unicast will either free the nskb or attach it to a socket */ | |
330 | status = netlink_unicast(ipqnl, nskb, peer_pid, MSG_DONTWAIT); | |
331 | if (status < 0) { | |
332 | queue_user_dropped++; | |
333 | goto err_out_unlock; | |
334 | } | |
335 | ||
336 | __ipq_enqueue_entry(entry); | |
337 | ||
338 | write_unlock_bh(&queue_lock); | |
339 | return status; | |
340 | ||
341 | err_out_free_nskb: | |
342 | kfree_skb(nskb); | |
343 | ||
344 | err_out_unlock: | |
345 | write_unlock_bh(&queue_lock); | |
346 | ||
347 | err_out_free: | |
348 | kfree(entry); | |
349 | return status; | |
350 | } | |
351 | ||
352 | static int | |
353 | ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct ipq_queue_entry *e) | |
354 | { | |
355 | int diff; | |
356 | struct iphdr *user_iph = (struct iphdr *)v->payload; | |
357 | ||
358 | if (v->data_len < sizeof(*user_iph)) | |
359 | return 0; | |
360 | diff = v->data_len - e->skb->len; | |
361 | if (diff < 0) | |
362 | skb_trim(e->skb, v->data_len); | |
363 | else if (diff > 0) { | |
364 | if (v->data_len > 0xFFFF) | |
365 | return -EINVAL; | |
366 | if (diff > skb_tailroom(e->skb)) { | |
367 | struct sk_buff *newskb; | |
368 | ||
369 | newskb = skb_copy_expand(e->skb, | |
370 | skb_headroom(e->skb), | |
371 | diff, | |
372 | GFP_ATOMIC); | |
373 | if (newskb == NULL) { | |
374 | printk(KERN_WARNING "ip_queue: OOM " | |
375 | "in mangle, dropping packet\n"); | |
376 | return -ENOMEM; | |
377 | } | |
378 | if (e->skb->sk) | |
379 | skb_set_owner_w(newskb, e->skb->sk); | |
380 | kfree_skb(e->skb); | |
381 | e->skb = newskb; | |
382 | } | |
383 | skb_put(e->skb, diff); | |
384 | } | |
385 | if (!skb_ip_make_writable(&e->skb, v->data_len)) | |
386 | return -ENOMEM; | |
387 | memcpy(e->skb->data, v->payload, v->data_len); | |
388 | e->skb->nfcache |= NFC_ALTERED; | |
389 | ||
390 | /* | |
391 | * Extra routing may needed on local out, as the QUEUE target never | |
392 | * returns control to the table. | |
393 | */ | |
394 | if (e->info->hook == NF_IP_LOCAL_OUT) { | |
395 | struct iphdr *iph = e->skb->nh.iph; | |
396 | ||
397 | if (!(iph->tos == e->rt_info.tos | |
398 | && iph->daddr == e->rt_info.daddr | |
399 | && iph->saddr == e->rt_info.saddr)) | |
400 | return ip_route_me_harder(&e->skb); | |
401 | } | |
402 | return 0; | |
403 | } | |
404 | ||
405 | static inline int | |
406 | id_cmp(struct ipq_queue_entry *e, unsigned long id) | |
407 | { | |
408 | return (id == (unsigned long )e); | |
409 | } | |
410 | ||
411 | static int | |
412 | ipq_set_verdict(struct ipq_verdict_msg *vmsg, unsigned int len) | |
413 | { | |
414 | struct ipq_queue_entry *entry; | |
415 | ||
416 | if (vmsg->value > NF_MAX_VERDICT) | |
417 | return -EINVAL; | |
418 | ||
419 | entry = ipq_find_dequeue_entry(id_cmp, vmsg->id); | |
420 | if (entry == NULL) | |
421 | return -ENOENT; | |
422 | else { | |
423 | int verdict = vmsg->value; | |
424 | ||
425 | if (vmsg->data_len && vmsg->data_len == len) | |
426 | if (ipq_mangle_ipv4(vmsg, entry) < 0) | |
427 | verdict = NF_DROP; | |
428 | ||
429 | ipq_issue_verdict(entry, verdict); | |
430 | return 0; | |
431 | } | |
432 | } | |
433 | ||
434 | static int | |
435 | ipq_set_mode(unsigned char mode, unsigned int range) | |
436 | { | |
437 | int status; | |
438 | ||
439 | write_lock_bh(&queue_lock); | |
440 | status = __ipq_set_mode(mode, range); | |
441 | write_unlock_bh(&queue_lock); | |
442 | return status; | |
443 | } | |
444 | ||
445 | static int | |
446 | ipq_receive_peer(struct ipq_peer_msg *pmsg, | |
447 | unsigned char type, unsigned int len) | |
448 | { | |
449 | int status = 0; | |
450 | ||
451 | if (len < sizeof(*pmsg)) | |
452 | return -EINVAL; | |
453 | ||
454 | switch (type) { | |
455 | case IPQM_MODE: | |
456 | status = ipq_set_mode(pmsg->msg.mode.value, | |
457 | pmsg->msg.mode.range); | |
458 | break; | |
459 | ||
460 | case IPQM_VERDICT: | |
461 | if (pmsg->msg.verdict.value > NF_MAX_VERDICT) | |
462 | status = -EINVAL; | |
463 | else | |
464 | status = ipq_set_verdict(&pmsg->msg.verdict, | |
465 | len - sizeof(*pmsg)); | |
466 | break; | |
467 | default: | |
468 | status = -EINVAL; | |
469 | } | |
470 | return status; | |
471 | } | |
472 | ||
473 | static int | |
474 | dev_cmp(struct ipq_queue_entry *entry, unsigned long ifindex) | |
475 | { | |
476 | if (entry->info->indev) | |
477 | if (entry->info->indev->ifindex == ifindex) | |
478 | return 1; | |
479 | ||
480 | if (entry->info->outdev) | |
481 | if (entry->info->outdev->ifindex == ifindex) | |
482 | return 1; | |
483 | ||
484 | return 0; | |
485 | } | |
486 | ||
487 | static void | |
488 | ipq_dev_drop(int ifindex) | |
489 | { | |
490 | struct ipq_queue_entry *entry; | |
491 | ||
492 | while ((entry = ipq_find_dequeue_entry(dev_cmp, ifindex)) != NULL) | |
493 | ipq_issue_verdict(entry, NF_DROP); | |
494 | } | |
495 | ||
496 | #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0) | |
497 | ||
498 | static inline void | |
499 | ipq_rcv_skb(struct sk_buff *skb) | |
500 | { | |
501 | int status, type, pid, flags, nlmsglen, skblen; | |
502 | struct nlmsghdr *nlh; | |
503 | ||
504 | skblen = skb->len; | |
505 | if (skblen < sizeof(*nlh)) | |
506 | return; | |
507 | ||
508 | nlh = (struct nlmsghdr *)skb->data; | |
509 | nlmsglen = nlh->nlmsg_len; | |
510 | if (nlmsglen < sizeof(*nlh) || skblen < nlmsglen) | |
511 | return; | |
512 | ||
513 | pid = nlh->nlmsg_pid; | |
514 | flags = nlh->nlmsg_flags; | |
515 | ||
516 | if(pid <= 0 || !(flags & NLM_F_REQUEST) || flags & NLM_F_MULTI) | |
517 | RCV_SKB_FAIL(-EINVAL); | |
518 | ||
519 | if (flags & MSG_TRUNC) | |
520 | RCV_SKB_FAIL(-ECOMM); | |
521 | ||
522 | type = nlh->nlmsg_type; | |
523 | if (type < NLMSG_NOOP || type >= IPQM_MAX) | |
524 | RCV_SKB_FAIL(-EINVAL); | |
525 | ||
526 | if (type <= IPQM_BASE) | |
527 | return; | |
528 | ||
529 | if (security_netlink_recv(skb)) | |
530 | RCV_SKB_FAIL(-EPERM); | |
531 | ||
532 | write_lock_bh(&queue_lock); | |
533 | ||
534 | if (peer_pid) { | |
535 | if (peer_pid != pid) { | |
536 | write_unlock_bh(&queue_lock); | |
537 | RCV_SKB_FAIL(-EBUSY); | |
538 | } | |
539 | } else { | |
540 | net_enable_timestamp(); | |
541 | peer_pid = pid; | |
542 | } | |
543 | ||
544 | write_unlock_bh(&queue_lock); | |
545 | ||
546 | status = ipq_receive_peer(NLMSG_DATA(nlh), type, | |
547 | skblen - NLMSG_LENGTH(0)); | |
548 | if (status < 0) | |
549 | RCV_SKB_FAIL(status); | |
550 | ||
551 | if (flags & NLM_F_ACK) | |
552 | netlink_ack(skb, nlh, 0); | |
553 | return; | |
554 | } | |
555 | ||
556 | static void | |
557 | ipq_rcv_sk(struct sock *sk, int len) | |
558 | { | |
2a0a6ebe HX |
559 | struct sk_buff *skb; |
560 | unsigned int qlen; | |
1da177e4 | 561 | |
2a0a6ebe | 562 | down(&ipqnl_sem); |
1da177e4 | 563 | |
2a0a6ebe HX |
564 | for (qlen = skb_queue_len(&sk->sk_receive_queue); qlen; qlen--) { |
565 | skb = skb_dequeue(&sk->sk_receive_queue); | |
566 | ipq_rcv_skb(skb); | |
567 | kfree_skb(skb); | |
568 | } | |
1da177e4 | 569 | |
2a0a6ebe | 570 | up(&ipqnl_sem); |
1da177e4 LT |
571 | } |
572 | ||
573 | static int | |
574 | ipq_rcv_dev_event(struct notifier_block *this, | |
575 | unsigned long event, void *ptr) | |
576 | { | |
577 | struct net_device *dev = ptr; | |
578 | ||
579 | /* Drop any packets associated with the downed device */ | |
580 | if (event == NETDEV_DOWN) | |
581 | ipq_dev_drop(dev->ifindex); | |
582 | return NOTIFY_DONE; | |
583 | } | |
584 | ||
585 | static struct notifier_block ipq_dev_notifier = { | |
586 | .notifier_call = ipq_rcv_dev_event, | |
587 | }; | |
588 | ||
589 | static int | |
590 | ipq_rcv_nl_event(struct notifier_block *this, | |
591 | unsigned long event, void *ptr) | |
592 | { | |
593 | struct netlink_notify *n = ptr; | |
594 | ||
595 | if (event == NETLINK_URELEASE && | |
596 | n->protocol == NETLINK_FIREWALL && n->pid) { | |
597 | write_lock_bh(&queue_lock); | |
598 | if (n->pid == peer_pid) | |
599 | __ipq_reset(); | |
600 | write_unlock_bh(&queue_lock); | |
601 | } | |
602 | return NOTIFY_DONE; | |
603 | } | |
604 | ||
605 | static struct notifier_block ipq_nl_notifier = { | |
606 | .notifier_call = ipq_rcv_nl_event, | |
607 | }; | |
608 | ||
609 | static struct ctl_table_header *ipq_sysctl_header; | |
610 | ||
611 | static ctl_table ipq_table[] = { | |
612 | { | |
613 | .ctl_name = NET_IPQ_QMAX, | |
614 | .procname = NET_IPQ_QMAX_NAME, | |
615 | .data = &queue_maxlen, | |
616 | .maxlen = sizeof(queue_maxlen), | |
617 | .mode = 0644, | |
618 | .proc_handler = proc_dointvec | |
619 | }, | |
620 | { .ctl_name = 0 } | |
621 | }; | |
622 | ||
623 | static ctl_table ipq_dir_table[] = { | |
624 | { | |
625 | .ctl_name = NET_IPV4, | |
626 | .procname = "ipv4", | |
627 | .mode = 0555, | |
628 | .child = ipq_table | |
629 | }, | |
630 | { .ctl_name = 0 } | |
631 | }; | |
632 | ||
633 | static ctl_table ipq_root_table[] = { | |
634 | { | |
635 | .ctl_name = CTL_NET, | |
636 | .procname = "net", | |
637 | .mode = 0555, | |
638 | .child = ipq_dir_table | |
639 | }, | |
640 | { .ctl_name = 0 } | |
641 | }; | |
642 | ||
643 | #ifdef CONFIG_PROC_FS | |
644 | static int | |
645 | ipq_get_info(char *buffer, char **start, off_t offset, int length) | |
646 | { | |
647 | int len; | |
648 | ||
649 | read_lock_bh(&queue_lock); | |
650 | ||
651 | len = sprintf(buffer, | |
652 | "Peer PID : %d\n" | |
653 | "Copy mode : %hu\n" | |
654 | "Copy range : %u\n" | |
655 | "Queue length : %u\n" | |
656 | "Queue max. length : %u\n" | |
657 | "Queue dropped : %u\n" | |
658 | "Netlink dropped : %u\n", | |
659 | peer_pid, | |
660 | copy_mode, | |
661 | copy_range, | |
662 | queue_total, | |
663 | queue_maxlen, | |
664 | queue_dropped, | |
665 | queue_user_dropped); | |
666 | ||
667 | read_unlock_bh(&queue_lock); | |
668 | ||
669 | *start = buffer + offset; | |
670 | len -= offset; | |
671 | if (len > length) | |
672 | len = length; | |
673 | else if (len < 0) | |
674 | len = 0; | |
675 | return len; | |
676 | } | |
677 | #endif /* CONFIG_PROC_FS */ | |
678 | ||
679 | static int | |
680 | init_or_cleanup(int init) | |
681 | { | |
682 | int status = -ENOMEM; | |
683 | struct proc_dir_entry *proc; | |
684 | ||
685 | if (!init) | |
686 | goto cleanup; | |
687 | ||
688 | netlink_register_notifier(&ipq_nl_notifier); | |
689 | ipqnl = netlink_kernel_create(NETLINK_FIREWALL, ipq_rcv_sk); | |
690 | if (ipqnl == NULL) { | |
691 | printk(KERN_ERR "ip_queue: failed to create netlink socket\n"); | |
692 | goto cleanup_netlink_notifier; | |
693 | } | |
694 | ||
695 | proc = proc_net_create(IPQ_PROC_FS_NAME, 0, ipq_get_info); | |
696 | if (proc) | |
697 | proc->owner = THIS_MODULE; | |
698 | else { | |
699 | printk(KERN_ERR "ip_queue: failed to create proc entry\n"); | |
700 | goto cleanup_ipqnl; | |
701 | } | |
702 | ||
703 | register_netdevice_notifier(&ipq_dev_notifier); | |
704 | ipq_sysctl_header = register_sysctl_table(ipq_root_table, 0); | |
705 | ||
706 | status = nf_register_queue_handler(PF_INET, ipq_enqueue_packet, NULL); | |
707 | if (status < 0) { | |
708 | printk(KERN_ERR "ip_queue: failed to register queue handler\n"); | |
709 | goto cleanup_sysctl; | |
710 | } | |
711 | return status; | |
712 | ||
713 | cleanup: | |
714 | nf_unregister_queue_handler(PF_INET); | |
715 | synchronize_net(); | |
716 | ipq_flush(NF_DROP); | |
717 | ||
718 | cleanup_sysctl: | |
719 | unregister_sysctl_table(ipq_sysctl_header); | |
720 | unregister_netdevice_notifier(&ipq_dev_notifier); | |
721 | proc_net_remove(IPQ_PROC_FS_NAME); | |
722 | ||
723 | cleanup_ipqnl: | |
724 | sock_release(ipqnl->sk_socket); | |
725 | down(&ipqnl_sem); | |
726 | up(&ipqnl_sem); | |
727 | ||
728 | cleanup_netlink_notifier: | |
729 | netlink_unregister_notifier(&ipq_nl_notifier); | |
730 | return status; | |
731 | } | |
732 | ||
733 | static int __init init(void) | |
734 | { | |
735 | ||
736 | return init_or_cleanup(1); | |
737 | } | |
738 | ||
739 | static void __exit fini(void) | |
740 | { | |
741 | init_or_cleanup(0); | |
742 | } | |
743 | ||
744 | MODULE_DESCRIPTION("IPv4 packet queue handler"); | |
745 | MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>"); | |
746 | MODULE_LICENSE("GPL"); | |
747 | ||
748 | module_init(init); | |
749 | module_exit(fini); |