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Commit | Line | Data |
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0597f268 HW |
1 | /* |
2 | * This is a module which is used for logging packets to userspace via | |
3 | * nfetlink. | |
4 | * | |
5 | * (C) 2005 by Harald Welte <laforge@netfilter.org> | |
6 | * | |
7 | * Based on the old ipv4-only ipt_ULOG.c: | |
8 | * (C) 2000-2004 by Harald Welte <laforge@netfilter.org> | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License version 2 as | |
12 | * published by the Free Software Foundation. | |
0597f268 HW |
13 | */ |
14 | #include <linux/module.h> | |
15 | #include <linux/skbuff.h> | |
16 | #include <linux/init.h> | |
17 | #include <linux/ip.h> | |
18 | #include <linux/ipv6.h> | |
19 | #include <linux/netdevice.h> | |
20 | #include <linux/netfilter.h> | |
21 | #include <linux/netlink.h> | |
22 | #include <linux/netfilter/nfnetlink.h> | |
23 | #include <linux/netfilter/nfnetlink_log.h> | |
24 | #include <linux/spinlock.h> | |
25 | #include <linux/sysctl.h> | |
26 | #include <linux/proc_fs.h> | |
27 | #include <linux/security.h> | |
28 | #include <linux/list.h> | |
29 | #include <linux/jhash.h> | |
30 | #include <linux/random.h> | |
31 | #include <net/sock.h> | |
f01ffbd6 | 32 | #include <net/netfilter/nf_log.h> |
0597f268 HW |
33 | |
34 | #include <asm/atomic.h> | |
35 | ||
fbcd923c HW |
36 | #ifdef CONFIG_BRIDGE_NETFILTER |
37 | #include "../bridge/br_private.h" | |
38 | #endif | |
39 | ||
c2db2924 | 40 | #define NFULNL_NLBUFSIZ_DEFAULT NLMSG_GOODSIZE |
6b6ec99a | 41 | #define NFULNL_TIMEOUT_DEFAULT HZ /* every second */ |
0597f268 | 42 | #define NFULNL_QTHRESH_DEFAULT 100 /* 100 packets */ |
6b6ec99a | 43 | #define NFULNL_COPY_RANGE_MAX 0xFFFF /* max packet size is limited by 16-bit struct nfattr nfa_len field */ |
0597f268 HW |
44 | |
45 | #define PRINTR(x, args...) do { if (net_ratelimit()) \ | |
46 | printk(x, ## args); } while (0); | |
47 | ||
0597f268 HW |
48 | struct nfulnl_instance { |
49 | struct hlist_node hlist; /* global list of instances */ | |
50 | spinlock_t lock; | |
51 | atomic_t use; /* use count */ | |
52 | ||
53 | unsigned int qlen; /* number of nlmsgs in skb */ | |
54 | struct sk_buff *skb; /* pre-allocatd skb */ | |
0597f268 HW |
55 | struct timer_list timer; |
56 | int peer_pid; /* PID of the peer process */ | |
57 | ||
58 | /* configurable parameters */ | |
59 | unsigned int flushtimeout; /* timeout until queue flush */ | |
60 | unsigned int nlbufsiz; /* netlink buffer allocation size */ | |
61 | unsigned int qthreshold; /* threshold of the queue */ | |
62 | u_int32_t copy_range; | |
0af5f6c1 | 63 | u_int32_t seq; /* instance-local sequential counter */ |
0597f268 | 64 | u_int16_t group_num; /* number of this queue */ |
0af5f6c1 | 65 | u_int16_t flags; |
601e68e1 | 66 | u_int8_t copy_mode; |
0597f268 HW |
67 | }; |
68 | ||
69 | static DEFINE_RWLOCK(instances_lock); | |
0af5f6c1 | 70 | static atomic_t global_seq; |
0597f268 HW |
71 | |
72 | #define INSTANCE_BUCKETS 16 | |
73 | static struct hlist_head instance_table[INSTANCE_BUCKETS]; | |
74 | static unsigned int hash_init; | |
75 | ||
76 | static inline u_int8_t instance_hashfn(u_int16_t group_num) | |
77 | { | |
78 | return ((group_num & 0xff) % INSTANCE_BUCKETS); | |
79 | } | |
80 | ||
81 | static struct nfulnl_instance * | |
82 | __instance_lookup(u_int16_t group_num) | |
83 | { | |
84 | struct hlist_head *head; | |
85 | struct hlist_node *pos; | |
86 | struct nfulnl_instance *inst; | |
87 | ||
0597f268 HW |
88 | head = &instance_table[instance_hashfn(group_num)]; |
89 | hlist_for_each_entry(inst, pos, head, hlist) { | |
90 | if (inst->group_num == group_num) | |
91 | return inst; | |
92 | } | |
93 | return NULL; | |
94 | } | |
95 | ||
96 | static inline void | |
97 | instance_get(struct nfulnl_instance *inst) | |
98 | { | |
99 | atomic_inc(&inst->use); | |
100 | } | |
101 | ||
102 | static struct nfulnl_instance * | |
103 | instance_lookup_get(u_int16_t group_num) | |
104 | { | |
105 | struct nfulnl_instance *inst; | |
106 | ||
107 | read_lock_bh(&instances_lock); | |
108 | inst = __instance_lookup(group_num); | |
109 | if (inst) | |
110 | instance_get(inst); | |
111 | read_unlock_bh(&instances_lock); | |
112 | ||
113 | return inst; | |
114 | } | |
115 | ||
116 | static void | |
117 | instance_put(struct nfulnl_instance *inst) | |
118 | { | |
119 | if (inst && atomic_dec_and_test(&inst->use)) { | |
0597f268 | 120 | kfree(inst); |
7d90e86d | 121 | module_put(THIS_MODULE); |
0597f268 HW |
122 | } |
123 | } | |
124 | ||
125 | static void nfulnl_timer(unsigned long data); | |
126 | ||
127 | static struct nfulnl_instance * | |
128 | instance_create(u_int16_t group_num, int pid) | |
129 | { | |
130 | struct nfulnl_instance *inst; | |
131 | ||
601e68e1 | 132 | write_lock_bh(&instances_lock); |
0597f268 HW |
133 | if (__instance_lookup(group_num)) { |
134 | inst = NULL; | |
0597f268 HW |
135 | goto out_unlock; |
136 | } | |
137 | ||
10dfdc69 | 138 | inst = kzalloc(sizeof(*inst), GFP_ATOMIC); |
0597f268 HW |
139 | if (!inst) |
140 | goto out_unlock; | |
141 | ||
aace57e0 MM |
142 | if (!try_module_get(THIS_MODULE)) { |
143 | kfree(inst); | |
144 | goto out_unlock; | |
145 | } | |
146 | ||
0597f268 | 147 | INIT_HLIST_NODE(&inst->hlist); |
181a46a5 | 148 | spin_lock_init(&inst->lock); |
0597f268 HW |
149 | /* needs to be two, since we _put() after creation */ |
150 | atomic_set(&inst->use, 2); | |
151 | ||
e6f689db | 152 | setup_timer(&inst->timer, nfulnl_timer, (unsigned long)inst); |
0597f268 HW |
153 | |
154 | inst->peer_pid = pid; | |
155 | inst->group_num = group_num; | |
156 | ||
157 | inst->qthreshold = NFULNL_QTHRESH_DEFAULT; | |
158 | inst->flushtimeout = NFULNL_TIMEOUT_DEFAULT; | |
159 | inst->nlbufsiz = NFULNL_NLBUFSIZ_DEFAULT; | |
160 | inst->copy_mode = NFULNL_COPY_PACKET; | |
6b6ec99a | 161 | inst->copy_range = NFULNL_COPY_RANGE_MAX; |
0597f268 | 162 | |
601e68e1 | 163 | hlist_add_head(&inst->hlist, |
0597f268 HW |
164 | &instance_table[instance_hashfn(group_num)]); |
165 | ||
0597f268 HW |
166 | write_unlock_bh(&instances_lock); |
167 | ||
168 | return inst; | |
169 | ||
0597f268 HW |
170 | out_unlock: |
171 | write_unlock_bh(&instances_lock); | |
172 | return NULL; | |
173 | } | |
174 | ||
e3567061 | 175 | static void __nfulnl_flush(struct nfulnl_instance *inst); |
0597f268 HW |
176 | |
177 | static void | |
9afdb00c | 178 | __instance_destroy(struct nfulnl_instance *inst) |
0597f268 HW |
179 | { |
180 | /* first pull it out of the global list */ | |
0597f268 HW |
181 | hlist_del(&inst->hlist); |
182 | ||
0597f268 HW |
183 | /* then flush all pending packets from skb */ |
184 | ||
185 | spin_lock_bh(&inst->lock); | |
e3567061 MM |
186 | if (inst->skb) |
187 | __nfulnl_flush(inst); | |
0597f268 HW |
188 | spin_unlock_bh(&inst->lock); |
189 | ||
190 | /* and finally put the refcount */ | |
191 | instance_put(inst); | |
0597f268 HW |
192 | } |
193 | ||
0597f268 HW |
194 | static inline void |
195 | instance_destroy(struct nfulnl_instance *inst) | |
196 | { | |
9afdb00c PM |
197 | write_lock_bh(&instances_lock); |
198 | __instance_destroy(inst); | |
199 | write_unlock_bh(&instances_lock); | |
0597f268 HW |
200 | } |
201 | ||
202 | static int | |
203 | nfulnl_set_mode(struct nfulnl_instance *inst, u_int8_t mode, | |
204 | unsigned int range) | |
205 | { | |
206 | int status = 0; | |
207 | ||
208 | spin_lock_bh(&inst->lock); | |
601e68e1 | 209 | |
0597f268 HW |
210 | switch (mode) { |
211 | case NFULNL_COPY_NONE: | |
212 | case NFULNL_COPY_META: | |
213 | inst->copy_mode = mode; | |
214 | inst->copy_range = 0; | |
215 | break; | |
601e68e1 | 216 | |
0597f268 HW |
217 | case NFULNL_COPY_PACKET: |
218 | inst->copy_mode = mode; | |
6b6ec99a MM |
219 | inst->copy_range = min_t(unsigned int, |
220 | range, NFULNL_COPY_RANGE_MAX); | |
0597f268 | 221 | break; |
601e68e1 | 222 | |
0597f268 HW |
223 | default: |
224 | status = -EINVAL; | |
225 | break; | |
226 | } | |
227 | ||
228 | spin_unlock_bh(&inst->lock); | |
229 | ||
230 | return status; | |
231 | } | |
232 | ||
233 | static int | |
234 | nfulnl_set_nlbufsiz(struct nfulnl_instance *inst, u_int32_t nlbufsiz) | |
235 | { | |
236 | int status; | |
237 | ||
238 | spin_lock_bh(&inst->lock); | |
239 | if (nlbufsiz < NFULNL_NLBUFSIZ_DEFAULT) | |
240 | status = -ERANGE; | |
241 | else if (nlbufsiz > 131072) | |
242 | status = -ERANGE; | |
243 | else { | |
244 | inst->nlbufsiz = nlbufsiz; | |
245 | status = 0; | |
246 | } | |
247 | spin_unlock_bh(&inst->lock); | |
248 | ||
249 | return status; | |
250 | } | |
251 | ||
252 | static int | |
253 | nfulnl_set_timeout(struct nfulnl_instance *inst, u_int32_t timeout) | |
254 | { | |
255 | spin_lock_bh(&inst->lock); | |
256 | inst->flushtimeout = timeout; | |
257 | spin_unlock_bh(&inst->lock); | |
258 | ||
259 | return 0; | |
260 | } | |
261 | ||
262 | static int | |
263 | nfulnl_set_qthresh(struct nfulnl_instance *inst, u_int32_t qthresh) | |
264 | { | |
265 | spin_lock_bh(&inst->lock); | |
266 | inst->qthreshold = qthresh; | |
267 | spin_unlock_bh(&inst->lock); | |
268 | ||
269 | return 0; | |
270 | } | |
271 | ||
0af5f6c1 HW |
272 | static int |
273 | nfulnl_set_flags(struct nfulnl_instance *inst, u_int16_t flags) | |
274 | { | |
275 | spin_lock_bh(&inst->lock); | |
ee433530 | 276 | inst->flags = flags; |
0af5f6c1 HW |
277 | spin_unlock_bh(&inst->lock); |
278 | ||
279 | return 0; | |
280 | } | |
281 | ||
c6a8f648 MM |
282 | static struct sk_buff * |
283 | nfulnl_alloc_skb(unsigned int inst_size, unsigned int pkt_size) | |
0597f268 HW |
284 | { |
285 | struct sk_buff *skb; | |
ad2ad0f9 | 286 | unsigned int n; |
0597f268 | 287 | |
0597f268 HW |
288 | /* alloc skb which should be big enough for a whole multipart |
289 | * message. WARNING: has to be <= 128k due to slab restrictions */ | |
290 | ||
ad2ad0f9 PM |
291 | n = max(inst_size, pkt_size); |
292 | skb = alloc_skb(n, GFP_ATOMIC); | |
0597f268 HW |
293 | if (!skb) { |
294 | PRINTR("nfnetlink_log: can't alloc whole buffer (%u bytes)\n", | |
295 | inst_size); | |
296 | ||
ad2ad0f9 PM |
297 | if (n > pkt_size) { |
298 | /* try to allocate only as much as we need for current | |
299 | * packet */ | |
0597f268 | 300 | |
ad2ad0f9 PM |
301 | skb = alloc_skb(pkt_size, GFP_ATOMIC); |
302 | if (!skb) | |
303 | PRINTR("nfnetlink_log: can't even alloc %u " | |
304 | "bytes\n", pkt_size); | |
305 | } | |
0597f268 HW |
306 | } |
307 | ||
308 | return skb; | |
309 | } | |
310 | ||
311 | static int | |
312 | __nfulnl_send(struct nfulnl_instance *inst) | |
313 | { | |
29c5d4af | 314 | int status = -1; |
0597f268 | 315 | |
0597f268 | 316 | if (inst->qlen > 1) |
29c5d4af EL |
317 | NLMSG_PUT(inst->skb, 0, 0, |
318 | NLMSG_DONE, | |
319 | sizeof(struct nfgenmsg)); | |
0597f268 HW |
320 | |
321 | status = nfnetlink_unicast(inst->skb, inst->peer_pid, MSG_DONTWAIT); | |
0597f268 HW |
322 | |
323 | inst->qlen = 0; | |
324 | inst->skb = NULL; | |
0597f268 | 325 | |
29c5d4af | 326 | nlmsg_failure: |
0597f268 HW |
327 | return status; |
328 | } | |
329 | ||
e3567061 MM |
330 | static void |
331 | __nfulnl_flush(struct nfulnl_instance *inst) | |
332 | { | |
333 | /* timer holds a reference */ | |
334 | if (del_timer(&inst->timer)) | |
335 | instance_put(inst); | |
336 | if (inst->skb) | |
337 | __nfulnl_send(inst); | |
338 | } | |
339 | ||
c6a8f648 MM |
340 | static void |
341 | nfulnl_timer(unsigned long data) | |
0597f268 | 342 | { |
601e68e1 | 343 | struct nfulnl_instance *inst = (struct nfulnl_instance *)data; |
0597f268 | 344 | |
0597f268 | 345 | spin_lock_bh(&inst->lock); |
370e6a87 MM |
346 | if (inst->skb) |
347 | __nfulnl_send(inst); | |
0597f268 | 348 | spin_unlock_bh(&inst->lock); |
05f7b7b3 | 349 | instance_put(inst); |
0597f268 HW |
350 | } |
351 | ||
0af5f6c1 HW |
352 | /* This is an inline function, we don't really care about a long |
353 | * list of arguments */ | |
601e68e1 | 354 | static inline int |
0597f268 | 355 | __build_packet_message(struct nfulnl_instance *inst, |
601e68e1 | 356 | const struct sk_buff *skb, |
0597f268 HW |
357 | unsigned int data_len, |
358 | unsigned int pf, | |
359 | unsigned int hooknum, | |
360 | const struct net_device *indev, | |
361 | const struct net_device *outdev, | |
362 | const struct nf_loginfo *li, | |
d7a5c324 | 363 | const char *prefix, unsigned int plen) |
0597f268 | 364 | { |
0597f268 HW |
365 | struct nfulnl_msg_packet_hdr pmsg; |
366 | struct nlmsghdr *nlh; | |
367 | struct nfgenmsg *nfmsg; | |
98a4a861 | 368 | __be32 tmp_uint; |
27a884dc | 369 | sk_buff_data_t old_tail = inst->skb->tail; |
0597f268 | 370 | |
601e68e1 | 371 | nlh = NLMSG_PUT(inst->skb, 0, 0, |
0597f268 HW |
372 | NFNL_SUBSYS_ULOG << 8 | NFULNL_MSG_PACKET, |
373 | sizeof(struct nfgenmsg)); | |
374 | nfmsg = NLMSG_DATA(nlh); | |
375 | nfmsg->nfgen_family = pf; | |
376 | nfmsg->version = NFNETLINK_V0; | |
377 | nfmsg->res_id = htons(inst->group_num); | |
378 | ||
febf0a43 | 379 | pmsg.hw_protocol = skb->protocol; |
0597f268 HW |
380 | pmsg.hook = hooknum; |
381 | ||
df6fb868 | 382 | NLA_PUT(inst->skb, NFULA_PACKET_HDR, sizeof(pmsg), &pmsg); |
0597f268 | 383 | |
d7a5c324 | 384 | if (prefix) |
df6fb868 | 385 | NLA_PUT(inst->skb, NFULA_PREFIX, plen, prefix); |
0597f268 HW |
386 | |
387 | if (indev) { | |
388 | tmp_uint = htonl(indev->ifindex); | |
fbcd923c | 389 | #ifndef CONFIG_BRIDGE_NETFILTER |
df6fb868 | 390 | NLA_PUT(inst->skb, NFULA_IFINDEX_INDEV, sizeof(tmp_uint), |
0597f268 | 391 | &tmp_uint); |
fbcd923c HW |
392 | #else |
393 | if (pf == PF_BRIDGE) { | |
394 | /* Case 1: outdev is physical input device, we need to | |
395 | * look for bridge group (when called from | |
396 | * netfilter_bridge) */ | |
df6fb868 | 397 | NLA_PUT(inst->skb, NFULA_IFINDEX_PHYSINDEV, |
fbcd923c HW |
398 | sizeof(tmp_uint), &tmp_uint); |
399 | /* this is the bridge group "brX" */ | |
400 | tmp_uint = htonl(indev->br_port->br->dev->ifindex); | |
df6fb868 | 401 | NLA_PUT(inst->skb, NFULA_IFINDEX_INDEV, |
fbcd923c HW |
402 | sizeof(tmp_uint), &tmp_uint); |
403 | } else { | |
404 | /* Case 2: indev is bridge group, we need to look for | |
405 | * physical device (when called from ipv4) */ | |
df6fb868 | 406 | NLA_PUT(inst->skb, NFULA_IFINDEX_INDEV, |
fbcd923c HW |
407 | sizeof(tmp_uint), &tmp_uint); |
408 | if (skb->nf_bridge && skb->nf_bridge->physindev) { | |
601e68e1 | 409 | tmp_uint = |
fbcd923c | 410 | htonl(skb->nf_bridge->physindev->ifindex); |
df6fb868 | 411 | NLA_PUT(inst->skb, NFULA_IFINDEX_PHYSINDEV, |
fbcd923c HW |
412 | sizeof(tmp_uint), &tmp_uint); |
413 | } | |
414 | } | |
415 | #endif | |
0597f268 HW |
416 | } |
417 | ||
418 | if (outdev) { | |
419 | tmp_uint = htonl(outdev->ifindex); | |
fbcd923c | 420 | #ifndef CONFIG_BRIDGE_NETFILTER |
df6fb868 | 421 | NLA_PUT(inst->skb, NFULA_IFINDEX_OUTDEV, sizeof(tmp_uint), |
0597f268 | 422 | &tmp_uint); |
fbcd923c HW |
423 | #else |
424 | if (pf == PF_BRIDGE) { | |
425 | /* Case 1: outdev is physical output device, we need to | |
426 | * look for bridge group (when called from | |
427 | * netfilter_bridge) */ | |
df6fb868 | 428 | NLA_PUT(inst->skb, NFULA_IFINDEX_PHYSOUTDEV, |
fbcd923c HW |
429 | sizeof(tmp_uint), &tmp_uint); |
430 | /* this is the bridge group "brX" */ | |
431 | tmp_uint = htonl(outdev->br_port->br->dev->ifindex); | |
df6fb868 | 432 | NLA_PUT(inst->skb, NFULA_IFINDEX_OUTDEV, |
fbcd923c HW |
433 | sizeof(tmp_uint), &tmp_uint); |
434 | } else { | |
435 | /* Case 2: indev is a bridge group, we need to look | |
436 | * for physical device (when called from ipv4) */ | |
df6fb868 | 437 | NLA_PUT(inst->skb, NFULA_IFINDEX_OUTDEV, |
fbcd923c | 438 | sizeof(tmp_uint), &tmp_uint); |
ba5dcee1 | 439 | if (skb->nf_bridge && skb->nf_bridge->physoutdev) { |
601e68e1 | 440 | tmp_uint = |
fbcd923c | 441 | htonl(skb->nf_bridge->physoutdev->ifindex); |
df6fb868 | 442 | NLA_PUT(inst->skb, NFULA_IFINDEX_PHYSOUTDEV, |
fbcd923c HW |
443 | sizeof(tmp_uint), &tmp_uint); |
444 | } | |
445 | } | |
446 | #endif | |
0597f268 HW |
447 | } |
448 | ||
82e91ffe TG |
449 | if (skb->mark) { |
450 | tmp_uint = htonl(skb->mark); | |
df6fb868 | 451 | NLA_PUT(inst->skb, NFULA_MARK, sizeof(tmp_uint), &tmp_uint); |
0597f268 HW |
452 | } |
453 | ||
b95cce35 | 454 | if (indev && skb->dev) { |
0597f268 | 455 | struct nfulnl_msg_packet_hw phw; |
b95cce35 SH |
456 | int len = dev_parse_header(skb, phw.hw_addr); |
457 | if (len > 0) { | |
458 | phw.hw_addrlen = htons(len); | |
df6fb868 | 459 | NLA_PUT(inst->skb, NFULA_HWADDR, sizeof(phw), &phw); |
b95cce35 | 460 | } |
0597f268 HW |
461 | } |
462 | ||
b7aa0bf7 | 463 | if (skb->tstamp.tv64) { |
0597f268 | 464 | struct nfulnl_msg_packet_timestamp ts; |
b7aa0bf7 ED |
465 | struct timeval tv = ktime_to_timeval(skb->tstamp); |
466 | ts.sec = cpu_to_be64(tv.tv_sec); | |
467 | ts.usec = cpu_to_be64(tv.tv_usec); | |
0597f268 | 468 | |
df6fb868 | 469 | NLA_PUT(inst->skb, NFULA_TIMESTAMP, sizeof(ts), &ts); |
0597f268 HW |
470 | } |
471 | ||
472 | /* UID */ | |
473 | if (skb->sk) { | |
474 | read_lock_bh(&skb->sk->sk_callback_lock); | |
475 | if (skb->sk->sk_socket && skb->sk->sk_socket->file) { | |
98a4a861 | 476 | __be32 uid = htonl(skb->sk->sk_socket->file->f_uid); |
df6fb868 | 477 | /* need to unlock here since NLA_PUT may goto */ |
0597f268 | 478 | read_unlock_bh(&skb->sk->sk_callback_lock); |
df6fb868 | 479 | NLA_PUT(inst->skb, NFULA_UID, sizeof(uid), &uid); |
0597f268 HW |
480 | } else |
481 | read_unlock_bh(&skb->sk->sk_callback_lock); | |
482 | } | |
483 | ||
0af5f6c1 HW |
484 | /* local sequence number */ |
485 | if (inst->flags & NFULNL_CFG_F_SEQ) { | |
486 | tmp_uint = htonl(inst->seq++); | |
df6fb868 | 487 | NLA_PUT(inst->skb, NFULA_SEQ, sizeof(tmp_uint), &tmp_uint); |
0af5f6c1 HW |
488 | } |
489 | /* global sequence number */ | |
490 | if (inst->flags & NFULNL_CFG_F_SEQ_GLOBAL) { | |
7fdeaf68 | 491 | tmp_uint = htonl(atomic_inc_return(&global_seq)); |
df6fb868 | 492 | NLA_PUT(inst->skb, NFULA_SEQ_GLOBAL, sizeof(tmp_uint), &tmp_uint); |
0af5f6c1 HW |
493 | } |
494 | ||
0597f268 | 495 | if (data_len) { |
df6fb868 PM |
496 | struct nlattr *nla; |
497 | int size = nla_attr_size(data_len); | |
0597f268 | 498 | |
df6fb868 | 499 | if (skb_tailroom(inst->skb) < nla_total_size(data_len)) { |
0597f268 HW |
500 | printk(KERN_WARNING "nfnetlink_log: no tailroom!\n"); |
501 | goto nlmsg_failure; | |
502 | } | |
503 | ||
df6fb868 PM |
504 | nla = (struct nlattr *)skb_put(inst->skb, nla_total_size(data_len)); |
505 | nla->nla_type = NFULA_PAYLOAD; | |
506 | nla->nla_len = size; | |
0597f268 | 507 | |
df6fb868 | 508 | if (skb_copy_bits(skb, 0, nla_data(nla), data_len)) |
0597f268 HW |
509 | BUG(); |
510 | } | |
601e68e1 | 511 | |
0597f268 HW |
512 | nlh->nlmsg_len = inst->skb->tail - old_tail; |
513 | return 0; | |
514 | ||
515 | nlmsg_failure: | |
df6fb868 | 516 | nla_put_failure: |
0597f268 HW |
517 | PRINTR(KERN_ERR "nfnetlink_log: error creating log nlmsg\n"); |
518 | return -1; | |
519 | } | |
520 | ||
521 | #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0) | |
522 | ||
523 | static struct nf_loginfo default_loginfo = { | |
524 | .type = NF_LOG_TYPE_ULOG, | |
525 | .u = { | |
526 | .ulog = { | |
527 | .copy_len = 0xffff, | |
528 | .group = 0, | |
529 | .qthreshold = 1, | |
530 | }, | |
531 | }, | |
532 | }; | |
533 | ||
534 | /* log handler for internal netfilter logging api */ | |
535 | static void | |
536 | nfulnl_log_packet(unsigned int pf, | |
537 | unsigned int hooknum, | |
538 | const struct sk_buff *skb, | |
539 | const struct net_device *in, | |
540 | const struct net_device *out, | |
541 | const struct nf_loginfo *li_user, | |
542 | const char *prefix) | |
543 | { | |
544 | unsigned int size, data_len; | |
545 | struct nfulnl_instance *inst; | |
546 | const struct nf_loginfo *li; | |
547 | unsigned int qthreshold; | |
d7a5c324 | 548 | unsigned int plen; |
0597f268 | 549 | |
601e68e1 | 550 | if (li_user && li_user->type == NF_LOG_TYPE_ULOG) |
0597f268 HW |
551 | li = li_user; |
552 | else | |
553 | li = &default_loginfo; | |
554 | ||
555 | inst = instance_lookup_get(li->u.ulog.group); | |
556 | if (!inst) | |
0597f268 | 557 | return; |
0597f268 | 558 | |
d7a5c324 PM |
559 | plen = 0; |
560 | if (prefix) | |
881dbfe8 | 561 | plen = strlen(prefix) + 1; |
d7a5c324 | 562 | |
0597f268 HW |
563 | /* FIXME: do we want to make the size calculation conditional based on |
564 | * what is actually present? way more branches and checks, but more | |
565 | * memory efficient... */ | |
df6fb868 PM |
566 | size = NLMSG_ALIGN(sizeof(struct nfgenmsg)) |
567 | + nla_total_size(sizeof(struct nfulnl_msg_packet_hdr)) | |
568 | + nla_total_size(sizeof(u_int32_t)) /* ifindex */ | |
569 | + nla_total_size(sizeof(u_int32_t)) /* ifindex */ | |
fbcd923c | 570 | #ifdef CONFIG_BRIDGE_NETFILTER |
df6fb868 PM |
571 | + nla_total_size(sizeof(u_int32_t)) /* ifindex */ |
572 | + nla_total_size(sizeof(u_int32_t)) /* ifindex */ | |
fbcd923c | 573 | #endif |
df6fb868 PM |
574 | + nla_total_size(sizeof(u_int32_t)) /* mark */ |
575 | + nla_total_size(sizeof(u_int32_t)) /* uid */ | |
576 | + nla_total_size(plen) /* prefix */ | |
577 | + nla_total_size(sizeof(struct nfulnl_msg_packet_hw)) | |
578 | + nla_total_size(sizeof(struct nfulnl_msg_packet_timestamp)); | |
0597f268 | 579 | |
0597f268 HW |
580 | spin_lock_bh(&inst->lock); |
581 | ||
0af5f6c1 | 582 | if (inst->flags & NFULNL_CFG_F_SEQ) |
df6fb868 | 583 | size += nla_total_size(sizeof(u_int32_t)); |
0af5f6c1 | 584 | if (inst->flags & NFULNL_CFG_F_SEQ_GLOBAL) |
df6fb868 | 585 | size += nla_total_size(sizeof(u_int32_t)); |
0af5f6c1 | 586 | |
0597f268 HW |
587 | qthreshold = inst->qthreshold; |
588 | /* per-rule qthreshold overrides per-instance */ | |
589 | if (qthreshold > li->u.ulog.qthreshold) | |
590 | qthreshold = li->u.ulog.qthreshold; | |
601e68e1 | 591 | |
0597f268 HW |
592 | switch (inst->copy_mode) { |
593 | case NFULNL_COPY_META: | |
594 | case NFULNL_COPY_NONE: | |
595 | data_len = 0; | |
596 | break; | |
601e68e1 | 597 | |
0597f268 | 598 | case NFULNL_COPY_PACKET: |
601e68e1 | 599 | if (inst->copy_range == 0 |
0597f268 HW |
600 | || inst->copy_range > skb->len) |
601 | data_len = skb->len; | |
602 | else | |
603 | data_len = inst->copy_range; | |
601e68e1 | 604 | |
df6fb868 | 605 | size += nla_total_size(data_len); |
0597f268 | 606 | break; |
601e68e1 | 607 | |
0597f268 | 608 | default: |
55b5a91e | 609 | goto unlock_and_release; |
0597f268 HW |
610 | } |
611 | ||
d63b043d MM |
612 | if (inst->skb && |
613 | size > skb_tailroom(inst->skb) - sizeof(struct nfgenmsg)) { | |
0597f268 HW |
614 | /* either the queue len is too high or we don't have |
615 | * enough room in the skb left. flush to userspace. */ | |
e3567061 | 616 | __nfulnl_flush(inst); |
55b5a91e | 617 | } |
0597f268 | 618 | |
55b5a91e MM |
619 | if (!inst->skb) { |
620 | inst->skb = nfulnl_alloc_skb(inst->nlbufsiz, size); | |
621 | if (!inst->skb) | |
0597f268 | 622 | goto alloc_failure; |
0597f268 HW |
623 | } |
624 | ||
0597f268 HW |
625 | inst->qlen++; |
626 | ||
627 | __build_packet_message(inst, skb, data_len, pf, | |
d7a5c324 | 628 | hooknum, in, out, li, prefix, plen); |
0597f268 | 629 | |
d63b043d MM |
630 | if (inst->qlen >= qthreshold) |
631 | __nfulnl_flush(inst); | |
0597f268 HW |
632 | /* timer_pending always called within inst->lock, so there |
633 | * is no chance of a race here */ | |
d63b043d | 634 | else if (!timer_pending(&inst->timer)) { |
0597f268 HW |
635 | instance_get(inst); |
636 | inst->timer.expires = jiffies + (inst->flushtimeout*HZ/100); | |
637 | add_timer(&inst->timer); | |
638 | } | |
0597f268 | 639 | |
ed32abea MM |
640 | unlock_and_release: |
641 | spin_unlock_bh(&inst->lock); | |
642 | instance_put(inst); | |
0597f268 HW |
643 | return; |
644 | ||
645 | alloc_failure: | |
0597f268 | 646 | /* FIXME: statistics */ |
ed32abea | 647 | goto unlock_and_release; |
0597f268 HW |
648 | } |
649 | ||
650 | static int | |
651 | nfulnl_rcv_nl_event(struct notifier_block *this, | |
652 | unsigned long event, void *ptr) | |
653 | { | |
654 | struct netlink_notify *n = ptr; | |
655 | ||
656 | if (event == NETLINK_URELEASE && | |
657 | n->protocol == NETLINK_NETFILTER && n->pid) { | |
658 | int i; | |
659 | ||
660 | /* destroy all instances for this pid */ | |
661 | write_lock_bh(&instances_lock); | |
662 | for (i = 0; i < INSTANCE_BUCKETS; i++) { | |
663 | struct hlist_node *tmp, *t2; | |
664 | struct nfulnl_instance *inst; | |
665 | struct hlist_head *head = &instance_table[i]; | |
666 | ||
667 | hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) { | |
b4b51029 EB |
668 | if ((n->net == &init_net) && |
669 | (n->pid == inst->peer_pid)) | |
0597f268 HW |
670 | __instance_destroy(inst); |
671 | } | |
672 | } | |
673 | write_unlock_bh(&instances_lock); | |
674 | } | |
675 | return NOTIFY_DONE; | |
676 | } | |
677 | ||
678 | static struct notifier_block nfulnl_rtnl_notifier = { | |
679 | .notifier_call = nfulnl_rcv_nl_event, | |
680 | }; | |
681 | ||
682 | static int | |
683 | nfulnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb, | |
df6fb868 | 684 | struct nlmsghdr *nlh, struct nlattr *nfqa[]) |
0597f268 HW |
685 | { |
686 | return -ENOTSUPP; | |
687 | } | |
688 | ||
7b2f9631 | 689 | static const struct nf_logger nfulnl_logger = { |
0597f268 HW |
690 | .name = "nfnetlink_log", |
691 | .logfn = &nfulnl_log_packet, | |
692 | .me = THIS_MODULE, | |
693 | }; | |
694 | ||
fd8281ad PM |
695 | static const struct nla_policy nfula_cfg_policy[NFULA_CFG_MAX+1] = { |
696 | [NFULA_CFG_CMD] = { .len = sizeof(struct nfulnl_msg_config_cmd) }, | |
697 | [NFULA_CFG_MODE] = { .len = sizeof(struct nfulnl_msg_config_mode) }, | |
698 | [NFULA_CFG_TIMEOUT] = { .type = NLA_U32 }, | |
699 | [NFULA_CFG_QTHRESH] = { .type = NLA_U32 }, | |
700 | [NFULA_CFG_NLBUFSIZ] = { .type = NLA_U32 }, | |
701 | [NFULA_CFG_FLAGS] = { .type = NLA_U16 }, | |
0597f268 HW |
702 | }; |
703 | ||
704 | static int | |
705 | nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, | |
df6fb868 | 706 | struct nlmsghdr *nlh, struct nlattr *nfula[]) |
0597f268 HW |
707 | { |
708 | struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); | |
709 | u_int16_t group_num = ntohs(nfmsg->res_id); | |
710 | struct nfulnl_instance *inst; | |
711 | int ret = 0; | |
712 | ||
0597f268 | 713 | inst = instance_lookup_get(group_num); |
c0506365 PM |
714 | if (inst && inst->peer_pid != NETLINK_CB(skb).pid) { |
715 | ret = -EPERM; | |
716 | goto out_put; | |
717 | } | |
718 | ||
df6fb868 | 719 | if (nfula[NFULA_CFG_CMD]) { |
0597f268 HW |
720 | u_int8_t pf = nfmsg->nfgen_family; |
721 | struct nfulnl_msg_config_cmd *cmd; | |
c0506365 | 722 | |
df6fb868 | 723 | cmd = nla_data(nfula[NFULA_CFG_CMD]); |
0597f268 HW |
724 | |
725 | switch (cmd->command) { | |
726 | case NFULNL_CFG_CMD_BIND: | |
727 | if (inst) { | |
728 | ret = -EBUSY; | |
729 | goto out_put; | |
730 | } | |
731 | ||
732 | inst = instance_create(group_num, | |
733 | NETLINK_CB(skb).pid); | |
734 | if (!inst) { | |
735 | ret = -EINVAL; | |
f414c16c | 736 | goto out; |
0597f268 HW |
737 | } |
738 | break; | |
739 | case NFULNL_CFG_CMD_UNBIND: | |
740 | if (!inst) { | |
741 | ret = -ENODEV; | |
f414c16c | 742 | goto out; |
0597f268 HW |
743 | } |
744 | ||
0597f268 | 745 | instance_destroy(inst); |
9a36e8c2 | 746 | goto out; |
0597f268 | 747 | case NFULNL_CFG_CMD_PF_BIND: |
0597f268 HW |
748 | ret = nf_log_register(pf, &nfulnl_logger); |
749 | break; | |
750 | case NFULNL_CFG_CMD_PF_UNBIND: | |
0597f268 HW |
751 | /* This is a bug and a feature. We cannot unregister |
752 | * other handlers, like nfnetlink_inst can */ | |
753 | nf_log_unregister_pf(pf); | |
754 | break; | |
755 | default: | |
cd21f0ac | 756 | ret = -ENOTSUPP; |
0597f268 HW |
757 | break; |
758 | } | |
0597f268 HW |
759 | } |
760 | ||
df6fb868 | 761 | if (nfula[NFULA_CFG_MODE]) { |
0597f268 | 762 | struct nfulnl_msg_config_mode *params; |
df6fb868 | 763 | params = nla_data(nfula[NFULA_CFG_MODE]); |
0597f268 | 764 | |
c0506365 PM |
765 | if (!inst) { |
766 | ret = -ENODEV; | |
767 | goto out; | |
768 | } | |
0597f268 | 769 | nfulnl_set_mode(inst, params->copy_mode, |
d1208b99 | 770 | ntohl(params->copy_range)); |
0597f268 HW |
771 | } |
772 | ||
df6fb868 | 773 | if (nfula[NFULA_CFG_TIMEOUT]) { |
98a4a861 | 774 | __be32 timeout = |
df6fb868 | 775 | *(__be32 *)nla_data(nfula[NFULA_CFG_TIMEOUT]); |
0597f268 | 776 | |
c0506365 PM |
777 | if (!inst) { |
778 | ret = -ENODEV; | |
779 | goto out; | |
780 | } | |
0597f268 HW |
781 | nfulnl_set_timeout(inst, ntohl(timeout)); |
782 | } | |
783 | ||
df6fb868 | 784 | if (nfula[NFULA_CFG_NLBUFSIZ]) { |
98a4a861 | 785 | __be32 nlbufsiz = |
df6fb868 | 786 | *(__be32 *)nla_data(nfula[NFULA_CFG_NLBUFSIZ]); |
0597f268 | 787 | |
c0506365 PM |
788 | if (!inst) { |
789 | ret = -ENODEV; | |
790 | goto out; | |
791 | } | |
0597f268 HW |
792 | nfulnl_set_nlbufsiz(inst, ntohl(nlbufsiz)); |
793 | } | |
794 | ||
df6fb868 | 795 | if (nfula[NFULA_CFG_QTHRESH]) { |
7ac00a24 | 796 | __be32 qthresh = |
df6fb868 | 797 | *(__be32 *)nla_data(nfula[NFULA_CFG_QTHRESH]); |
0597f268 | 798 | |
c0506365 PM |
799 | if (!inst) { |
800 | ret = -ENODEV; | |
801 | goto out; | |
802 | } | |
0597f268 HW |
803 | nfulnl_set_qthresh(inst, ntohl(qthresh)); |
804 | } | |
805 | ||
df6fb868 | 806 | if (nfula[NFULA_CFG_FLAGS]) { |
98a4a861 | 807 | __be16 flags = |
df6fb868 | 808 | *(__be16 *)nla_data(nfula[NFULA_CFG_FLAGS]); |
c0506365 PM |
809 | |
810 | if (!inst) { | |
811 | ret = -ENODEV; | |
812 | goto out; | |
813 | } | |
ee433530 | 814 | nfulnl_set_flags(inst, ntohs(flags)); |
0af5f6c1 HW |
815 | } |
816 | ||
0597f268 HW |
817 | out_put: |
818 | instance_put(inst); | |
dd16704e | 819 | out: |
0597f268 HW |
820 | return ret; |
821 | } | |
822 | ||
7c8d4cb4 | 823 | static const struct nfnl_callback nfulnl_cb[NFULNL_MSG_MAX] = { |
0597f268 | 824 | [NFULNL_MSG_PACKET] = { .call = nfulnl_recv_unsupp, |
37d2e7a2 | 825 | .attr_count = NFULA_MAX, }, |
0597f268 | 826 | [NFULNL_MSG_CONFIG] = { .call = nfulnl_recv_config, |
fd8281ad PM |
827 | .attr_count = NFULA_CFG_MAX, |
828 | .policy = nfula_cfg_policy }, | |
0597f268 HW |
829 | }; |
830 | ||
7c8d4cb4 | 831 | static const struct nfnetlink_subsystem nfulnl_subsys = { |
0597f268 HW |
832 | .name = "log", |
833 | .subsys_id = NFNL_SUBSYS_ULOG, | |
834 | .cb_count = NFULNL_MSG_MAX, | |
0597f268 HW |
835 | .cb = nfulnl_cb, |
836 | }; | |
837 | ||
838 | #ifdef CONFIG_PROC_FS | |
839 | struct iter_state { | |
840 | unsigned int bucket; | |
841 | }; | |
842 | ||
f76cdcee | 843 | static struct hlist_node *get_first(struct iter_state *st) |
0597f268 | 844 | { |
0597f268 HW |
845 | if (!st) |
846 | return NULL; | |
847 | ||
848 | for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) { | |
849 | if (!hlist_empty(&instance_table[st->bucket])) | |
850 | return instance_table[st->bucket].first; | |
851 | } | |
852 | return NULL; | |
853 | } | |
854 | ||
f76cdcee | 855 | static struct hlist_node *get_next(struct iter_state *st, struct hlist_node *h) |
0597f268 | 856 | { |
0597f268 HW |
857 | h = h->next; |
858 | while (!h) { | |
859 | if (++st->bucket >= INSTANCE_BUCKETS) | |
860 | return NULL; | |
861 | ||
862 | h = instance_table[st->bucket].first; | |
863 | } | |
864 | return h; | |
865 | } | |
866 | ||
f76cdcee | 867 | static struct hlist_node *get_idx(struct iter_state *st, loff_t pos) |
0597f268 HW |
868 | { |
869 | struct hlist_node *head; | |
f76cdcee | 870 | head = get_first(st); |
0597f268 HW |
871 | |
872 | if (head) | |
f76cdcee | 873 | while (pos && (head = get_next(st, head))) |
0597f268 HW |
874 | pos--; |
875 | return pos ? NULL : head; | |
876 | } | |
877 | ||
878 | static void *seq_start(struct seq_file *seq, loff_t *pos) | |
879 | { | |
880 | read_lock_bh(&instances_lock); | |
f76cdcee | 881 | return get_idx(seq->private, *pos); |
0597f268 HW |
882 | } |
883 | ||
884 | static void *seq_next(struct seq_file *s, void *v, loff_t *pos) | |
885 | { | |
886 | (*pos)++; | |
f76cdcee | 887 | return get_next(s->private, v); |
0597f268 HW |
888 | } |
889 | ||
890 | static void seq_stop(struct seq_file *s, void *v) | |
891 | { | |
892 | read_unlock_bh(&instances_lock); | |
893 | } | |
894 | ||
895 | static int seq_show(struct seq_file *s, void *v) | |
896 | { | |
897 | const struct nfulnl_instance *inst = v; | |
898 | ||
601e68e1 | 899 | return seq_printf(s, "%5d %6d %5d %1d %5d %6d %2d\n", |
0597f268 | 900 | inst->group_num, |
601e68e1 | 901 | inst->peer_pid, inst->qlen, |
0597f268 HW |
902 | inst->copy_mode, inst->copy_range, |
903 | inst->flushtimeout, atomic_read(&inst->use)); | |
904 | } | |
905 | ||
56b3d975 | 906 | static const struct seq_operations nful_seq_ops = { |
0597f268 HW |
907 | .start = seq_start, |
908 | .next = seq_next, | |
909 | .stop = seq_stop, | |
910 | .show = seq_show, | |
911 | }; | |
912 | ||
913 | static int nful_open(struct inode *inode, struct file *file) | |
914 | { | |
e2da5913 PE |
915 | return seq_open_private(file, &nful_seq_ops, |
916 | sizeof(struct iter_state)); | |
0597f268 HW |
917 | } |
918 | ||
da7071d7 | 919 | static const struct file_operations nful_file_ops = { |
0597f268 HW |
920 | .owner = THIS_MODULE, |
921 | .open = nful_open, | |
922 | .read = seq_read, | |
923 | .llseek = seq_lseek, | |
924 | .release = seq_release_private, | |
925 | }; | |
926 | ||
927 | #endif /* PROC_FS */ | |
928 | ||
32292a7f | 929 | static int __init nfnetlink_log_init(void) |
0597f268 HW |
930 | { |
931 | int i, status = -ENOMEM; | |
932 | #ifdef CONFIG_PROC_FS | |
933 | struct proc_dir_entry *proc_nful; | |
934 | #endif | |
601e68e1 | 935 | |
0597f268 HW |
936 | for (i = 0; i < INSTANCE_BUCKETS; i++) |
937 | INIT_HLIST_HEAD(&instance_table[i]); | |
601e68e1 | 938 | |
0597f268 HW |
939 | /* it's not really all that important to have a random value, so |
940 | * we can do this from the init function, even if there hasn't | |
941 | * been that much entropy yet */ | |
942 | get_random_bytes(&hash_init, sizeof(hash_init)); | |
943 | ||
944 | netlink_register_notifier(&nfulnl_rtnl_notifier); | |
945 | status = nfnetlink_subsys_register(&nfulnl_subsys); | |
946 | if (status < 0) { | |
947 | printk(KERN_ERR "log: failed to create netlink socket\n"); | |
948 | goto cleanup_netlink_notifier; | |
949 | } | |
950 | ||
951 | #ifdef CONFIG_PROC_FS | |
952 | proc_nful = create_proc_entry("nfnetlink_log", 0440, | |
953 | proc_net_netfilter); | |
954 | if (!proc_nful) | |
955 | goto cleanup_subsys; | |
956 | proc_nful->proc_fops = &nful_file_ops; | |
957 | #endif | |
0597f268 HW |
958 | return status; |
959 | ||
0597f268 | 960 | #ifdef CONFIG_PROC_FS |
0597f268 | 961 | cleanup_subsys: |
0597f268 | 962 | nfnetlink_subsys_unregister(&nfulnl_subsys); |
32292a7f | 963 | #endif |
0597f268 HW |
964 | cleanup_netlink_notifier: |
965 | netlink_unregister_notifier(&nfulnl_rtnl_notifier); | |
966 | return status; | |
967 | } | |
968 | ||
65b4b4e8 | 969 | static void __exit nfnetlink_log_fini(void) |
0597f268 | 970 | { |
e92ad99c | 971 | nf_log_unregister(&nfulnl_logger); |
32292a7f PM |
972 | #ifdef CONFIG_PROC_FS |
973 | remove_proc_entry("nfnetlink_log", proc_net_netfilter); | |
974 | #endif | |
975 | nfnetlink_subsys_unregister(&nfulnl_subsys); | |
976 | netlink_unregister_notifier(&nfulnl_rtnl_notifier); | |
0597f268 HW |
977 | } |
978 | ||
979 | MODULE_DESCRIPTION("netfilter userspace logging"); | |
980 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); | |
981 | MODULE_LICENSE("GPL"); | |
f682faef | 982 | MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ULOG); |
0597f268 | 983 | |
65b4b4e8 AM |
984 | module_init(nfnetlink_log_init); |
985 | module_exit(nfnetlink_log_fini); |