Commit | Line | Data |
---|---|---|
9fb9cbb1 YK |
1 | /* Connection state tracking for netfilter. This is separated from, |
2 | but required by, the NAT layer; it can also be used by an iptables | |
3 | extension. */ | |
4 | ||
5 | /* (C) 1999-2001 Paul `Rusty' Russell | |
dc808fe2 | 6 | * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> |
9fb9cbb1 YK |
7 | * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org> |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License version 2 as | |
11 | * published by the Free Software Foundation. | |
9fb9cbb1 YK |
12 | */ |
13 | ||
9fb9cbb1 YK |
14 | #include <linux/types.h> |
15 | #include <linux/netfilter.h> | |
16 | #include <linux/module.h> | |
d43c36dc | 17 | #include <linux/sched.h> |
9fb9cbb1 YK |
18 | #include <linux/skbuff.h> |
19 | #include <linux/proc_fs.h> | |
20 | #include <linux/vmalloc.h> | |
21 | #include <linux/stddef.h> | |
22 | #include <linux/slab.h> | |
23 | #include <linux/random.h> | |
24 | #include <linux/jhash.h> | |
25 | #include <linux/err.h> | |
26 | #include <linux/percpu.h> | |
27 | #include <linux/moduleparam.h> | |
28 | #include <linux/notifier.h> | |
29 | #include <linux/kernel.h> | |
30 | #include <linux/netdevice.h> | |
31 | #include <linux/socket.h> | |
d7fe0f24 | 32 | #include <linux/mm.h> |
d696c7bd | 33 | #include <linux/nsproxy.h> |
ea781f19 | 34 | #include <linux/rculist_nulls.h> |
9fb9cbb1 | 35 | |
9fb9cbb1 YK |
36 | #include <net/netfilter/nf_conntrack.h> |
37 | #include <net/netfilter/nf_conntrack_l3proto.h> | |
605dcad6 | 38 | #include <net/netfilter/nf_conntrack_l4proto.h> |
77ab9cff | 39 | #include <net/netfilter/nf_conntrack_expect.h> |
9fb9cbb1 YK |
40 | #include <net/netfilter/nf_conntrack_helper.h> |
41 | #include <net/netfilter/nf_conntrack_core.h> | |
ecfab2c9 | 42 | #include <net/netfilter/nf_conntrack_extend.h> |
58401572 | 43 | #include <net/netfilter/nf_conntrack_acct.h> |
a0891aa6 | 44 | #include <net/netfilter/nf_conntrack_ecache.h> |
5d0aa2cc | 45 | #include <net/netfilter/nf_conntrack_zones.h> |
a992ca2a | 46 | #include <net/netfilter/nf_conntrack_timestamp.h> |
dd705072 | 47 | #include <net/netfilter/nf_conntrack_timeout.h> |
e6a7d3c0 | 48 | #include <net/netfilter/nf_nat.h> |
e17b666a | 49 | #include <net/netfilter/nf_nat_core.h> |
9fb9cbb1 | 50 | |
dc808fe2 | 51 | #define NF_CONNTRACK_VERSION "0.5.0" |
9fb9cbb1 | 52 | |
e17b666a PM |
53 | int (*nfnetlink_parse_nat_setup_hook)(struct nf_conn *ct, |
54 | enum nf_nat_manip_type manip, | |
39938324 | 55 | const struct nlattr *attr) __read_mostly; |
e6a7d3c0 PNA |
56 | EXPORT_SYMBOL_GPL(nfnetlink_parse_nat_setup_hook); |
57 | ||
c7232c99 PM |
58 | int (*nf_nat_seq_adjust_hook)(struct sk_buff *skb, |
59 | struct nf_conn *ct, | |
60 | enum ip_conntrack_info ctinfo, | |
61 | unsigned int protoff); | |
62 | EXPORT_SYMBOL_GPL(nf_nat_seq_adjust_hook); | |
63 | ||
f8ba1aff | 64 | DEFINE_SPINLOCK(nf_conntrack_lock); |
13b18339 | 65 | EXPORT_SYMBOL_GPL(nf_conntrack_lock); |
9fb9cbb1 | 66 | |
e2b7606c | 67 | unsigned int nf_conntrack_htable_size __read_mostly; |
13b18339 PM |
68 | EXPORT_SYMBOL_GPL(nf_conntrack_htable_size); |
69 | ||
e478075c | 70 | unsigned int nf_conntrack_max __read_mostly; |
a999e683 | 71 | EXPORT_SYMBOL_GPL(nf_conntrack_max); |
13b18339 | 72 | |
b3c5163f ED |
73 | DEFINE_PER_CPU(struct nf_conn, nf_conntrack_untracked); |
74 | EXPORT_PER_CPU_SYMBOL(nf_conntrack_untracked); | |
13b18339 | 75 | |
f682cefa | 76 | unsigned int nf_conntrack_hash_rnd __read_mostly; |
4d4e61c6 | 77 | EXPORT_SYMBOL_GPL(nf_conntrack_hash_rnd); |
9fb9cbb1 | 78 | |
99f07e91 | 79 | static u32 hash_conntrack_raw(const struct nf_conntrack_tuple *tuple, u16 zone) |
9fb9cbb1 | 80 | { |
0794935e | 81 | unsigned int n; |
0794935e PM |
82 | |
83 | /* The direction must be ignored, so we hash everything up to the | |
84 | * destination ports (which is a multiple of 4) and treat the last | |
85 | * three bytes manually. | |
86 | */ | |
87 | n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32); | |
99f07e91 CG |
88 | return jhash2((u32 *)tuple, n, zone ^ nf_conntrack_hash_rnd ^ |
89 | (((__force __u16)tuple->dst.u.all << 16) | | |
90 | tuple->dst.protonum)); | |
91 | } | |
92 | ||
93 | static u32 __hash_bucket(u32 hash, unsigned int size) | |
94 | { | |
95 | return ((u64)hash * size) >> 32; | |
96 | } | |
97 | ||
98 | static u32 hash_bucket(u32 hash, const struct net *net) | |
99 | { | |
100 | return __hash_bucket(hash, net->ct.htable_size); | |
101 | } | |
0794935e | 102 | |
99f07e91 CG |
103 | static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple, |
104 | u16 zone, unsigned int size) | |
105 | { | |
106 | return __hash_bucket(hash_conntrack_raw(tuple, zone), size); | |
9fb9cbb1 YK |
107 | } |
108 | ||
5d0aa2cc | 109 | static inline u_int32_t hash_conntrack(const struct net *net, u16 zone, |
d696c7bd | 110 | const struct nf_conntrack_tuple *tuple) |
9fb9cbb1 | 111 | { |
99f07e91 | 112 | return __hash_conntrack(tuple, zone, net->ct.htable_size); |
9fb9cbb1 YK |
113 | } |
114 | ||
5f2b4c90 | 115 | bool |
9fb9cbb1 YK |
116 | nf_ct_get_tuple(const struct sk_buff *skb, |
117 | unsigned int nhoff, | |
118 | unsigned int dataoff, | |
119 | u_int16_t l3num, | |
120 | u_int8_t protonum, | |
121 | struct nf_conntrack_tuple *tuple, | |
122 | const struct nf_conntrack_l3proto *l3proto, | |
605dcad6 | 123 | const struct nf_conntrack_l4proto *l4proto) |
9fb9cbb1 | 124 | { |
443a70d5 | 125 | memset(tuple, 0, sizeof(*tuple)); |
9fb9cbb1 YK |
126 | |
127 | tuple->src.l3num = l3num; | |
128 | if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0) | |
5f2b4c90 | 129 | return false; |
9fb9cbb1 YK |
130 | |
131 | tuple->dst.protonum = protonum; | |
132 | tuple->dst.dir = IP_CT_DIR_ORIGINAL; | |
133 | ||
605dcad6 | 134 | return l4proto->pkt_to_tuple(skb, dataoff, tuple); |
9fb9cbb1 | 135 | } |
13b18339 | 136 | EXPORT_SYMBOL_GPL(nf_ct_get_tuple); |
9fb9cbb1 | 137 | |
5f2b4c90 JE |
138 | bool nf_ct_get_tuplepr(const struct sk_buff *skb, unsigned int nhoff, |
139 | u_int16_t l3num, struct nf_conntrack_tuple *tuple) | |
e2a3123f YK |
140 | { |
141 | struct nf_conntrack_l3proto *l3proto; | |
142 | struct nf_conntrack_l4proto *l4proto; | |
143 | unsigned int protoff; | |
144 | u_int8_t protonum; | |
145 | int ret; | |
146 | ||
147 | rcu_read_lock(); | |
148 | ||
149 | l3proto = __nf_ct_l3proto_find(l3num); | |
150 | ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum); | |
151 | if (ret != NF_ACCEPT) { | |
152 | rcu_read_unlock(); | |
5f2b4c90 | 153 | return false; |
e2a3123f YK |
154 | } |
155 | ||
156 | l4proto = __nf_ct_l4proto_find(l3num, protonum); | |
157 | ||
158 | ret = nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, tuple, | |
159 | l3proto, l4proto); | |
160 | ||
161 | rcu_read_unlock(); | |
162 | return ret; | |
163 | } | |
164 | EXPORT_SYMBOL_GPL(nf_ct_get_tuplepr); | |
165 | ||
5f2b4c90 | 166 | bool |
9fb9cbb1 YK |
167 | nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse, |
168 | const struct nf_conntrack_tuple *orig, | |
169 | const struct nf_conntrack_l3proto *l3proto, | |
605dcad6 | 170 | const struct nf_conntrack_l4proto *l4proto) |
9fb9cbb1 | 171 | { |
443a70d5 | 172 | memset(inverse, 0, sizeof(*inverse)); |
9fb9cbb1 YK |
173 | |
174 | inverse->src.l3num = orig->src.l3num; | |
175 | if (l3proto->invert_tuple(inverse, orig) == 0) | |
5f2b4c90 | 176 | return false; |
9fb9cbb1 YK |
177 | |
178 | inverse->dst.dir = !orig->dst.dir; | |
179 | ||
180 | inverse->dst.protonum = orig->dst.protonum; | |
605dcad6 | 181 | return l4proto->invert_tuple(inverse, orig); |
9fb9cbb1 | 182 | } |
13b18339 | 183 | EXPORT_SYMBOL_GPL(nf_ct_invert_tuple); |
9fb9cbb1 | 184 | |
9fb9cbb1 YK |
185 | static void |
186 | clean_from_lists(struct nf_conn *ct) | |
187 | { | |
0d53778e | 188 | pr_debug("clean_from_lists(%p)\n", ct); |
ea781f19 ED |
189 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); |
190 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode); | |
9fb9cbb1 YK |
191 | |
192 | /* Destroy all pending expectations */ | |
c1d10adb | 193 | nf_ct_remove_expectations(ct); |
9fb9cbb1 YK |
194 | } |
195 | ||
196 | static void | |
197 | destroy_conntrack(struct nf_conntrack *nfct) | |
198 | { | |
199 | struct nf_conn *ct = (struct nf_conn *)nfct; | |
0d55af87 | 200 | struct net *net = nf_ct_net(ct); |
605dcad6 | 201 | struct nf_conntrack_l4proto *l4proto; |
9fb9cbb1 | 202 | |
0d53778e | 203 | pr_debug("destroy_conntrack(%p)\n", ct); |
9fb9cbb1 YK |
204 | NF_CT_ASSERT(atomic_read(&nfct->use) == 0); |
205 | NF_CT_ASSERT(!timer_pending(&ct->timeout)); | |
206 | ||
9fb9cbb1 YK |
207 | /* To make sure we don't get any weird locking issues here: |
208 | * destroy_conntrack() MUST NOT be called with a write lock | |
209 | * to nf_conntrack_lock!!! -HW */ | |
923f4902 | 210 | rcu_read_lock(); |
5e8fbe2a | 211 | l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct)); |
605dcad6 MJ |
212 | if (l4proto && l4proto->destroy) |
213 | l4proto->destroy(ct); | |
9fb9cbb1 | 214 | |
982d9a9c | 215 | rcu_read_unlock(); |
9fb9cbb1 | 216 | |
f8ba1aff | 217 | spin_lock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
218 | /* Expectations will have been removed in clean_from_lists, |
219 | * except TFTP can create an expectation on the first packet, | |
220 | * before connection is in the list, so we need to clean here, | |
221 | * too. */ | |
c1d10adb | 222 | nf_ct_remove_expectations(ct); |
9fb9cbb1 YK |
223 | |
224 | /* We overload first tuple to link into unconfirmed list. */ | |
225 | if (!nf_ct_is_confirmed(ct)) { | |
ea781f19 ED |
226 | BUG_ON(hlist_nulls_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode)); |
227 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); | |
9fb9cbb1 YK |
228 | } |
229 | ||
0d55af87 | 230 | NF_CT_STAT_INC(net, delete); |
f8ba1aff | 231 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
232 | |
233 | if (ct->master) | |
234 | nf_ct_put(ct->master); | |
235 | ||
0d53778e | 236 | pr_debug("destroy_conntrack: returning ct=%p to slab\n", ct); |
9fb9cbb1 YK |
237 | nf_conntrack_free(ct); |
238 | } | |
239 | ||
dd7669a9 | 240 | void nf_ct_delete_from_lists(struct nf_conn *ct) |
9fb9cbb1 | 241 | { |
0d55af87 | 242 | struct net *net = nf_ct_net(ct); |
9fb9cbb1 | 243 | |
9858a3ae | 244 | nf_ct_helper_destroy(ct); |
f8ba1aff | 245 | spin_lock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
246 | /* Inside lock so preempt is disabled on module removal path. |
247 | * Otherwise we can get spurious warnings. */ | |
0d55af87 | 248 | NF_CT_STAT_INC(net, delete_list); |
9fb9cbb1 | 249 | clean_from_lists(ct); |
f8ba1aff | 250 | spin_unlock_bh(&nf_conntrack_lock); |
dd7669a9 PNA |
251 | } |
252 | EXPORT_SYMBOL_GPL(nf_ct_delete_from_lists); | |
253 | ||
254 | static void death_by_event(unsigned long ul_conntrack) | |
255 | { | |
256 | struct nf_conn *ct = (void *)ul_conntrack; | |
257 | struct net *net = nf_ct_net(ct); | |
5b423f6a PNA |
258 | struct nf_conntrack_ecache *ecache = nf_ct_ecache_find(ct); |
259 | ||
260 | BUG_ON(ecache == NULL); | |
dd7669a9 PNA |
261 | |
262 | if (nf_conntrack_event(IPCT_DESTROY, ct) < 0) { | |
263 | /* bad luck, let's retry again */ | |
5b423f6a | 264 | ecache->timeout.expires = jiffies + |
dd7669a9 | 265 | (random32() % net->ct.sysctl_events_retry_timeout); |
5b423f6a | 266 | add_timer(&ecache->timeout); |
dd7669a9 PNA |
267 | return; |
268 | } | |
269 | /* we've got the event delivered, now it's dying */ | |
270 | set_bit(IPS_DYING_BIT, &ct->status); | |
271 | spin_lock(&nf_conntrack_lock); | |
272 | hlist_nulls_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); | |
273 | spin_unlock(&nf_conntrack_lock); | |
274 | nf_ct_put(ct); | |
275 | } | |
276 | ||
277 | void nf_ct_insert_dying_list(struct nf_conn *ct) | |
278 | { | |
279 | struct net *net = nf_ct_net(ct); | |
5b423f6a PNA |
280 | struct nf_conntrack_ecache *ecache = nf_ct_ecache_find(ct); |
281 | ||
282 | BUG_ON(ecache == NULL); | |
dd7669a9 PNA |
283 | |
284 | /* add this conntrack to the dying list */ | |
285 | spin_lock_bh(&nf_conntrack_lock); | |
286 | hlist_nulls_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, | |
287 | &net->ct.dying); | |
288 | spin_unlock_bh(&nf_conntrack_lock); | |
289 | /* set a new timer to retry event delivery */ | |
5b423f6a PNA |
290 | setup_timer(&ecache->timeout, death_by_event, (unsigned long)ct); |
291 | ecache->timeout.expires = jiffies + | |
dd7669a9 | 292 | (random32() % net->ct.sysctl_events_retry_timeout); |
5b423f6a | 293 | add_timer(&ecache->timeout); |
dd7669a9 PNA |
294 | } |
295 | EXPORT_SYMBOL_GPL(nf_ct_insert_dying_list); | |
296 | ||
297 | static void death_by_timeout(unsigned long ul_conntrack) | |
298 | { | |
299 | struct nf_conn *ct = (void *)ul_conntrack; | |
a992ca2a PNA |
300 | struct nf_conn_tstamp *tstamp; |
301 | ||
302 | tstamp = nf_conn_tstamp_find(ct); | |
303 | if (tstamp && tstamp->stop == 0) | |
304 | tstamp->stop = ktime_to_ns(ktime_get_real()); | |
dd7669a9 PNA |
305 | |
306 | if (!test_bit(IPS_DYING_BIT, &ct->status) && | |
307 | unlikely(nf_conntrack_event(IPCT_DESTROY, ct) < 0)) { | |
308 | /* destroy event was not delivered */ | |
309 | nf_ct_delete_from_lists(ct); | |
310 | nf_ct_insert_dying_list(ct); | |
311 | return; | |
312 | } | |
313 | set_bit(IPS_DYING_BIT, &ct->status); | |
314 | nf_ct_delete_from_lists(ct); | |
9fb9cbb1 YK |
315 | nf_ct_put(ct); |
316 | } | |
317 | ||
ea781f19 ED |
318 | /* |
319 | * Warning : | |
320 | * - Caller must take a reference on returned object | |
321 | * and recheck nf_ct_tuple_equal(tuple, &h->tuple) | |
322 | * OR | |
323 | * - Caller must lock nf_conntrack_lock before calling this function | |
324 | */ | |
99f07e91 CG |
325 | static struct nf_conntrack_tuple_hash * |
326 | ____nf_conntrack_find(struct net *net, u16 zone, | |
327 | const struct nf_conntrack_tuple *tuple, u32 hash) | |
9fb9cbb1 YK |
328 | { |
329 | struct nf_conntrack_tuple_hash *h; | |
ea781f19 | 330 | struct hlist_nulls_node *n; |
99f07e91 | 331 | unsigned int bucket = hash_bucket(hash, net); |
9fb9cbb1 | 332 | |
4e29e9ec PM |
333 | /* Disable BHs the entire time since we normally need to disable them |
334 | * at least once for the stats anyway. | |
335 | */ | |
336 | local_bh_disable(); | |
ea781f19 | 337 | begin: |
99f07e91 | 338 | hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[bucket], hnnode) { |
5d0aa2cc PM |
339 | if (nf_ct_tuple_equal(tuple, &h->tuple) && |
340 | nf_ct_zone(nf_ct_tuplehash_to_ctrack(h)) == zone) { | |
0d55af87 | 341 | NF_CT_STAT_INC(net, found); |
4e29e9ec | 342 | local_bh_enable(); |
9fb9cbb1 YK |
343 | return h; |
344 | } | |
0d55af87 | 345 | NF_CT_STAT_INC(net, searched); |
9fb9cbb1 | 346 | } |
ea781f19 ED |
347 | /* |
348 | * if the nulls value we got at the end of this lookup is | |
349 | * not the expected one, we must restart lookup. | |
350 | * We probably met an item that was moved to another chain. | |
351 | */ | |
99f07e91 | 352 | if (get_nulls_value(n) != bucket) { |
af740b2c | 353 | NF_CT_STAT_INC(net, search_restart); |
ea781f19 | 354 | goto begin; |
af740b2c | 355 | } |
4e29e9ec | 356 | local_bh_enable(); |
9fb9cbb1 YK |
357 | |
358 | return NULL; | |
359 | } | |
99f07e91 CG |
360 | |
361 | struct nf_conntrack_tuple_hash * | |
362 | __nf_conntrack_find(struct net *net, u16 zone, | |
363 | const struct nf_conntrack_tuple *tuple) | |
364 | { | |
365 | return ____nf_conntrack_find(net, zone, tuple, | |
366 | hash_conntrack_raw(tuple, zone)); | |
367 | } | |
13b18339 | 368 | EXPORT_SYMBOL_GPL(__nf_conntrack_find); |
9fb9cbb1 YK |
369 | |
370 | /* Find a connection corresponding to a tuple. */ | |
99f07e91 CG |
371 | static struct nf_conntrack_tuple_hash * |
372 | __nf_conntrack_find_get(struct net *net, u16 zone, | |
373 | const struct nf_conntrack_tuple *tuple, u32 hash) | |
9fb9cbb1 YK |
374 | { |
375 | struct nf_conntrack_tuple_hash *h; | |
76507f69 | 376 | struct nf_conn *ct; |
9fb9cbb1 | 377 | |
76507f69 | 378 | rcu_read_lock(); |
ea781f19 | 379 | begin: |
99f07e91 | 380 | h = ____nf_conntrack_find(net, zone, tuple, hash); |
76507f69 PM |
381 | if (h) { |
382 | ct = nf_ct_tuplehash_to_ctrack(h); | |
8d8890b7 PM |
383 | if (unlikely(nf_ct_is_dying(ct) || |
384 | !atomic_inc_not_zero(&ct->ct_general.use))) | |
76507f69 | 385 | h = NULL; |
ea781f19 | 386 | else { |
5d0aa2cc PM |
387 | if (unlikely(!nf_ct_tuple_equal(tuple, &h->tuple) || |
388 | nf_ct_zone(ct) != zone)) { | |
ea781f19 ED |
389 | nf_ct_put(ct); |
390 | goto begin; | |
391 | } | |
392 | } | |
76507f69 PM |
393 | } |
394 | rcu_read_unlock(); | |
9fb9cbb1 YK |
395 | |
396 | return h; | |
397 | } | |
99f07e91 CG |
398 | |
399 | struct nf_conntrack_tuple_hash * | |
400 | nf_conntrack_find_get(struct net *net, u16 zone, | |
401 | const struct nf_conntrack_tuple *tuple) | |
402 | { | |
403 | return __nf_conntrack_find_get(net, zone, tuple, | |
404 | hash_conntrack_raw(tuple, zone)); | |
405 | } | |
13b18339 | 406 | EXPORT_SYMBOL_GPL(nf_conntrack_find_get); |
9fb9cbb1 | 407 | |
c1d10adb PNA |
408 | static void __nf_conntrack_hash_insert(struct nf_conn *ct, |
409 | unsigned int hash, | |
601e68e1 | 410 | unsigned int repl_hash) |
c1d10adb | 411 | { |
400dad39 AD |
412 | struct net *net = nf_ct_net(ct); |
413 | ||
ea781f19 | 414 | hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, |
400dad39 | 415 | &net->ct.hash[hash]); |
ea781f19 | 416 | hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode, |
400dad39 | 417 | &net->ct.hash[repl_hash]); |
c1d10adb PNA |
418 | } |
419 | ||
7d367e06 JK |
420 | int |
421 | nf_conntrack_hash_check_insert(struct nf_conn *ct) | |
c1d10adb | 422 | { |
d696c7bd | 423 | struct net *net = nf_ct_net(ct); |
c1d10adb | 424 | unsigned int hash, repl_hash; |
7d367e06 JK |
425 | struct nf_conntrack_tuple_hash *h; |
426 | struct hlist_nulls_node *n; | |
5d0aa2cc | 427 | u16 zone; |
c1d10adb | 428 | |
5d0aa2cc | 429 | zone = nf_ct_zone(ct); |
7d367e06 JK |
430 | hash = hash_conntrack(net, zone, |
431 | &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); | |
432 | repl_hash = hash_conntrack(net, zone, | |
433 | &ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
434 | ||
435 | spin_lock_bh(&nf_conntrack_lock); | |
436 | ||
437 | /* See if there's one in the list already, including reverse */ | |
438 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[hash], hnnode) | |
439 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, | |
440 | &h->tuple) && | |
441 | zone == nf_ct_zone(nf_ct_tuplehash_to_ctrack(h))) | |
442 | goto out; | |
443 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[repl_hash], hnnode) | |
444 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple, | |
445 | &h->tuple) && | |
446 | zone == nf_ct_zone(nf_ct_tuplehash_to_ctrack(h))) | |
447 | goto out; | |
c1d10adb | 448 | |
7d367e06 JK |
449 | add_timer(&ct->timeout); |
450 | nf_conntrack_get(&ct->ct_general); | |
c1d10adb | 451 | __nf_conntrack_hash_insert(ct, hash, repl_hash); |
7d367e06 JK |
452 | NF_CT_STAT_INC(net, insert); |
453 | spin_unlock_bh(&nf_conntrack_lock); | |
454 | ||
455 | return 0; | |
456 | ||
457 | out: | |
458 | NF_CT_STAT_INC(net, insert_failed); | |
459 | spin_unlock_bh(&nf_conntrack_lock); | |
460 | return -EEXIST; | |
c1d10adb | 461 | } |
7d367e06 | 462 | EXPORT_SYMBOL_GPL(nf_conntrack_hash_check_insert); |
c1d10adb | 463 | |
9fb9cbb1 YK |
464 | /* Confirm a connection given skb; places it in hash table */ |
465 | int | |
3db05fea | 466 | __nf_conntrack_confirm(struct sk_buff *skb) |
9fb9cbb1 YK |
467 | { |
468 | unsigned int hash, repl_hash; | |
df0933dc | 469 | struct nf_conntrack_tuple_hash *h; |
9fb9cbb1 | 470 | struct nf_conn *ct; |
df0933dc | 471 | struct nf_conn_help *help; |
a992ca2a | 472 | struct nf_conn_tstamp *tstamp; |
ea781f19 | 473 | struct hlist_nulls_node *n; |
9fb9cbb1 | 474 | enum ip_conntrack_info ctinfo; |
400dad39 | 475 | struct net *net; |
5d0aa2cc | 476 | u16 zone; |
9fb9cbb1 | 477 | |
3db05fea | 478 | ct = nf_ct_get(skb, &ctinfo); |
400dad39 | 479 | net = nf_ct_net(ct); |
9fb9cbb1 YK |
480 | |
481 | /* ipt_REJECT uses nf_conntrack_attach to attach related | |
482 | ICMP/TCP RST packets in other direction. Actual packet | |
483 | which created connection will be IP_CT_NEW or for an | |
484 | expected connection, IP_CT_RELATED. */ | |
485 | if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) | |
486 | return NF_ACCEPT; | |
487 | ||
5d0aa2cc | 488 | zone = nf_ct_zone(ct); |
99f07e91 CG |
489 | /* reuse the hash saved before */ |
490 | hash = *(unsigned long *)&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev; | |
491 | hash = hash_bucket(hash, net); | |
492 | repl_hash = hash_conntrack(net, zone, | |
493 | &ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
9fb9cbb1 YK |
494 | |
495 | /* We're not in hash table, and we refuse to set up related | |
496 | connections for unconfirmed conns. But packet copies and | |
497 | REJECT will give spurious warnings here. */ | |
498 | /* NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 1); */ | |
499 | ||
25985edc | 500 | /* No external references means no one else could have |
9fb9cbb1 YK |
501 | confirmed us. */ |
502 | NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); | |
0d53778e | 503 | pr_debug("Confirming conntrack %p\n", ct); |
9fb9cbb1 | 504 | |
f8ba1aff | 505 | spin_lock_bh(&nf_conntrack_lock); |
9fb9cbb1 | 506 | |
fc350777 JM |
507 | /* We have to check the DYING flag inside the lock to prevent |
508 | a race against nf_ct_get_next_corpse() possibly called from | |
509 | user context, else we insert an already 'dead' hash, blocking | |
510 | further use of that particular connection -JM */ | |
511 | ||
512 | if (unlikely(nf_ct_is_dying(ct))) { | |
513 | spin_unlock_bh(&nf_conntrack_lock); | |
514 | return NF_ACCEPT; | |
515 | } | |
516 | ||
9fb9cbb1 YK |
517 | /* See if there's one in the list already, including reverse: |
518 | NAT could have grabbed it without realizing, since we're | |
519 | not in the hash. If there is, we lost race. */ | |
ea781f19 | 520 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[hash], hnnode) |
df0933dc | 521 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, |
5d0aa2cc PM |
522 | &h->tuple) && |
523 | zone == nf_ct_zone(nf_ct_tuplehash_to_ctrack(h))) | |
df0933dc | 524 | goto out; |
ea781f19 | 525 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[repl_hash], hnnode) |
df0933dc | 526 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple, |
5d0aa2cc PM |
527 | &h->tuple) && |
528 | zone == nf_ct_zone(nf_ct_tuplehash_to_ctrack(h))) | |
df0933dc | 529 | goto out; |
9fb9cbb1 | 530 | |
df0933dc | 531 | /* Remove from unconfirmed list */ |
ea781f19 | 532 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); |
df0933dc | 533 | |
df0933dc PM |
534 | /* Timer relative to confirmation time, not original |
535 | setting time, otherwise we'd get timer wrap in | |
536 | weird delay cases. */ | |
537 | ct->timeout.expires += jiffies; | |
538 | add_timer(&ct->timeout); | |
539 | atomic_inc(&ct->ct_general.use); | |
45eec341 | 540 | ct->status |= IPS_CONFIRMED; |
5c8ec910 | 541 | |
a992ca2a PNA |
542 | /* set conntrack timestamp, if enabled. */ |
543 | tstamp = nf_conn_tstamp_find(ct); | |
544 | if (tstamp) { | |
545 | if (skb->tstamp.tv64 == 0) | |
e3192690 | 546 | __net_timestamp(skb); |
a992ca2a PNA |
547 | |
548 | tstamp->start = ktime_to_ns(skb->tstamp); | |
549 | } | |
5c8ec910 PM |
550 | /* Since the lookup is lockless, hash insertion must be done after |
551 | * starting the timer and setting the CONFIRMED bit. The RCU barriers | |
552 | * guarantee that no other CPU can find the conntrack before the above | |
553 | * stores are visible. | |
554 | */ | |
555 | __nf_conntrack_hash_insert(ct, hash, repl_hash); | |
0d55af87 | 556 | NF_CT_STAT_INC(net, insert); |
f8ba1aff | 557 | spin_unlock_bh(&nf_conntrack_lock); |
5c8ec910 | 558 | |
df0933dc PM |
559 | help = nfct_help(ct); |
560 | if (help && help->helper) | |
a71996fc | 561 | nf_conntrack_event_cache(IPCT_HELPER, ct); |
17e6e4ea | 562 | |
df0933dc | 563 | nf_conntrack_event_cache(master_ct(ct) ? |
a71996fc | 564 | IPCT_RELATED : IPCT_NEW, ct); |
df0933dc | 565 | return NF_ACCEPT; |
9fb9cbb1 | 566 | |
df0933dc | 567 | out: |
0d55af87 | 568 | NF_CT_STAT_INC(net, insert_failed); |
f8ba1aff | 569 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
570 | return NF_DROP; |
571 | } | |
13b18339 | 572 | EXPORT_SYMBOL_GPL(__nf_conntrack_confirm); |
9fb9cbb1 YK |
573 | |
574 | /* Returns true if a connection correspondings to the tuple (required | |
575 | for NAT). */ | |
576 | int | |
577 | nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple, | |
578 | const struct nf_conn *ignored_conntrack) | |
579 | { | |
400dad39 | 580 | struct net *net = nf_ct_net(ignored_conntrack); |
9fb9cbb1 | 581 | struct nf_conntrack_tuple_hash *h; |
ea781f19 | 582 | struct hlist_nulls_node *n; |
5d0aa2cc PM |
583 | struct nf_conn *ct; |
584 | u16 zone = nf_ct_zone(ignored_conntrack); | |
585 | unsigned int hash = hash_conntrack(net, zone, tuple); | |
9fb9cbb1 | 586 | |
4e29e9ec PM |
587 | /* Disable BHs the entire time since we need to disable them at |
588 | * least once for the stats anyway. | |
589 | */ | |
590 | rcu_read_lock_bh(); | |
ea781f19 | 591 | hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], hnnode) { |
5d0aa2cc PM |
592 | ct = nf_ct_tuplehash_to_ctrack(h); |
593 | if (ct != ignored_conntrack && | |
594 | nf_ct_tuple_equal(tuple, &h->tuple) && | |
595 | nf_ct_zone(ct) == zone) { | |
0d55af87 | 596 | NF_CT_STAT_INC(net, found); |
4e29e9ec | 597 | rcu_read_unlock_bh(); |
ba419aff PM |
598 | return 1; |
599 | } | |
0d55af87 | 600 | NF_CT_STAT_INC(net, searched); |
ba419aff | 601 | } |
4e29e9ec | 602 | rcu_read_unlock_bh(); |
9fb9cbb1 | 603 | |
ba419aff | 604 | return 0; |
9fb9cbb1 | 605 | } |
13b18339 | 606 | EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken); |
9fb9cbb1 | 607 | |
7ae7730f PM |
608 | #define NF_CT_EVICTION_RANGE 8 |
609 | ||
9fb9cbb1 YK |
610 | /* There's a small race here where we may free a just-assured |
611 | connection. Too bad: we're in trouble anyway. */ | |
400dad39 | 612 | static noinline int early_drop(struct net *net, unsigned int hash) |
9fb9cbb1 | 613 | { |
f205c5e0 | 614 | /* Use oldest entry, which is roughly LRU */ |
9fb9cbb1 | 615 | struct nf_conntrack_tuple_hash *h; |
df0933dc | 616 | struct nf_conn *ct = NULL, *tmp; |
ea781f19 | 617 | struct hlist_nulls_node *n; |
7ae7730f | 618 | unsigned int i, cnt = 0; |
9fb9cbb1 YK |
619 | int dropped = 0; |
620 | ||
76507f69 | 621 | rcu_read_lock(); |
d696c7bd | 622 | for (i = 0; i < net->ct.htable_size; i++) { |
ea781f19 ED |
623 | hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], |
624 | hnnode) { | |
7ae7730f PM |
625 | tmp = nf_ct_tuplehash_to_ctrack(h); |
626 | if (!test_bit(IPS_ASSURED_BIT, &tmp->status)) | |
627 | ct = tmp; | |
628 | cnt++; | |
629 | } | |
76507f69 | 630 | |
5ae27aa2 CG |
631 | if (ct != NULL) { |
632 | if (likely(!nf_ct_is_dying(ct) && | |
633 | atomic_inc_not_zero(&ct->ct_general.use))) | |
634 | break; | |
635 | else | |
636 | ct = NULL; | |
637 | } | |
638 | ||
639 | if (cnt >= NF_CT_EVICTION_RANGE) | |
7ae7730f | 640 | break; |
5ae27aa2 | 641 | |
d696c7bd | 642 | hash = (hash + 1) % net->ct.htable_size; |
9fb9cbb1 | 643 | } |
76507f69 | 644 | rcu_read_unlock(); |
9fb9cbb1 YK |
645 | |
646 | if (!ct) | |
647 | return dropped; | |
648 | ||
649 | if (del_timer(&ct->timeout)) { | |
650 | death_by_timeout((unsigned long)ct); | |
74138511 PNA |
651 | /* Check if we indeed killed this entry. Reliable event |
652 | delivery may have inserted it into the dying list. */ | |
653 | if (test_bit(IPS_DYING_BIT, &ct->status)) { | |
654 | dropped = 1; | |
655 | NF_CT_STAT_INC_ATOMIC(net, early_drop); | |
656 | } | |
9fb9cbb1 YK |
657 | } |
658 | nf_ct_put(ct); | |
659 | return dropped; | |
660 | } | |
661 | ||
f682cefa CG |
662 | void init_nf_conntrack_hash_rnd(void) |
663 | { | |
664 | unsigned int rand; | |
665 | ||
666 | /* | |
667 | * Why not initialize nf_conntrack_rnd in a "init()" function ? | |
668 | * Because there isn't enough entropy when system initializing, | |
669 | * and we initialize it as late as possible. | |
670 | */ | |
671 | do { | |
672 | get_random_bytes(&rand, sizeof(rand)); | |
673 | } while (!rand); | |
674 | cmpxchg(&nf_conntrack_hash_rnd, 0, rand); | |
675 | } | |
676 | ||
99f07e91 CG |
677 | static struct nf_conn * |
678 | __nf_conntrack_alloc(struct net *net, u16 zone, | |
679 | const struct nf_conntrack_tuple *orig, | |
680 | const struct nf_conntrack_tuple *repl, | |
681 | gfp_t gfp, u32 hash) | |
9fb9cbb1 | 682 | { |
cd7fcbf1 | 683 | struct nf_conn *ct; |
9fb9cbb1 | 684 | |
b2390969 | 685 | if (unlikely(!nf_conntrack_hash_rnd)) { |
f682cefa | 686 | init_nf_conntrack_hash_rnd(); |
99f07e91 CG |
687 | /* recompute the hash as nf_conntrack_hash_rnd is initialized */ |
688 | hash = hash_conntrack_raw(orig, zone); | |
9fb9cbb1 YK |
689 | } |
690 | ||
5251e2d2 | 691 | /* We don't want any race condition at early drop stage */ |
49ac8713 | 692 | atomic_inc(&net->ct.count); |
5251e2d2 | 693 | |
76eb9460 | 694 | if (nf_conntrack_max && |
49ac8713 | 695 | unlikely(atomic_read(&net->ct.count) > nf_conntrack_max)) { |
99f07e91 | 696 | if (!early_drop(net, hash_bucket(hash, net))) { |
49ac8713 | 697 | atomic_dec(&net->ct.count); |
e87cc472 | 698 | net_warn_ratelimited("nf_conntrack: table full, dropping packet\n"); |
9fb9cbb1 YK |
699 | return ERR_PTR(-ENOMEM); |
700 | } | |
701 | } | |
702 | ||
941297f4 ED |
703 | /* |
704 | * Do not use kmem_cache_zalloc(), as this cache uses | |
705 | * SLAB_DESTROY_BY_RCU. | |
706 | */ | |
5b3501fa | 707 | ct = kmem_cache_alloc(net->ct.nf_conntrack_cachep, gfp); |
c88130bc | 708 | if (ct == NULL) { |
49ac8713 | 709 | atomic_dec(&net->ct.count); |
dacd2a1a | 710 | return ERR_PTR(-ENOMEM); |
9fb9cbb1 | 711 | } |
941297f4 ED |
712 | /* |
713 | * Let ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode.next | |
714 | * and ct->tuplehash[IP_CT_DIR_REPLY].hnnode.next unchanged. | |
715 | */ | |
716 | memset(&ct->tuplehash[IP_CT_DIR_MAX], 0, | |
e5fc9e7a CG |
717 | offsetof(struct nf_conn, proto) - |
718 | offsetof(struct nf_conn, tuplehash[IP_CT_DIR_MAX])); | |
440f0d58 | 719 | spin_lock_init(&ct->lock); |
c88130bc | 720 | ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig; |
941297f4 | 721 | ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode.pprev = NULL; |
c88130bc | 722 | ct->tuplehash[IP_CT_DIR_REPLY].tuple = *repl; |
99f07e91 CG |
723 | /* save hash for reusing when confirming */ |
724 | *(unsigned long *)(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev) = hash; | |
9fb9cbb1 | 725 | /* Don't set timer yet: wait for confirmation */ |
c88130bc | 726 | setup_timer(&ct->timeout, death_by_timeout, (unsigned long)ct); |
c2d9ba9b | 727 | write_pnet(&ct->ct_net, net); |
5d0aa2cc PM |
728 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
729 | if (zone) { | |
730 | struct nf_conntrack_zone *nf_ct_zone; | |
731 | ||
732 | nf_ct_zone = nf_ct_ext_add(ct, NF_CT_EXT_ZONE, GFP_ATOMIC); | |
733 | if (!nf_ct_zone) | |
734 | goto out_free; | |
735 | nf_ct_zone->id = zone; | |
736 | } | |
737 | #endif | |
941297f4 ED |
738 | /* |
739 | * changes to lookup keys must be done before setting refcnt to 1 | |
740 | */ | |
741 | smp_wmb(); | |
742 | atomic_set(&ct->ct_general.use, 1); | |
c88130bc | 743 | return ct; |
5d0aa2cc PM |
744 | |
745 | #ifdef CONFIG_NF_CONNTRACK_ZONES | |
746 | out_free: | |
d96fc659 | 747 | atomic_dec(&net->ct.count); |
5d0aa2cc PM |
748 | kmem_cache_free(net->ct.nf_conntrack_cachep, ct); |
749 | return ERR_PTR(-ENOMEM); | |
750 | #endif | |
9fb9cbb1 | 751 | } |
99f07e91 CG |
752 | |
753 | struct nf_conn *nf_conntrack_alloc(struct net *net, u16 zone, | |
754 | const struct nf_conntrack_tuple *orig, | |
755 | const struct nf_conntrack_tuple *repl, | |
756 | gfp_t gfp) | |
757 | { | |
758 | return __nf_conntrack_alloc(net, zone, orig, repl, gfp, 0); | |
759 | } | |
13b18339 | 760 | EXPORT_SYMBOL_GPL(nf_conntrack_alloc); |
9fb9cbb1 | 761 | |
c88130bc | 762 | void nf_conntrack_free(struct nf_conn *ct) |
76507f69 | 763 | { |
1d45209d ED |
764 | struct net *net = nf_ct_net(ct); |
765 | ||
ceeff754 | 766 | nf_ct_ext_destroy(ct); |
1d45209d | 767 | atomic_dec(&net->ct.count); |
ea781f19 | 768 | nf_ct_ext_free(ct); |
5b3501fa | 769 | kmem_cache_free(net->ct.nf_conntrack_cachep, ct); |
76507f69 | 770 | } |
13b18339 | 771 | EXPORT_SYMBOL_GPL(nf_conntrack_free); |
9fb9cbb1 YK |
772 | |
773 | /* Allocate a new conntrack: we return -ENOMEM if classification | |
774 | failed due to stress. Otherwise it really is unclassifiable. */ | |
775 | static struct nf_conntrack_tuple_hash * | |
b2a15a60 | 776 | init_conntrack(struct net *net, struct nf_conn *tmpl, |
5a1fb391 | 777 | const struct nf_conntrack_tuple *tuple, |
9fb9cbb1 | 778 | struct nf_conntrack_l3proto *l3proto, |
605dcad6 | 779 | struct nf_conntrack_l4proto *l4proto, |
9fb9cbb1 | 780 | struct sk_buff *skb, |
60b5f8f7 | 781 | unsigned int dataoff, u32 hash) |
9fb9cbb1 | 782 | { |
c88130bc | 783 | struct nf_conn *ct; |
3c158f7f | 784 | struct nf_conn_help *help; |
9fb9cbb1 | 785 | struct nf_conntrack_tuple repl_tuple; |
b2a15a60 | 786 | struct nf_conntrack_ecache *ecache; |
9fb9cbb1 | 787 | struct nf_conntrack_expect *exp; |
5d0aa2cc | 788 | u16 zone = tmpl ? nf_ct_zone(tmpl) : NF_CT_DEFAULT_ZONE; |
60b5f8f7 PNA |
789 | struct nf_conn_timeout *timeout_ext; |
790 | unsigned int *timeouts; | |
9fb9cbb1 | 791 | |
605dcad6 | 792 | if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) { |
0d53778e | 793 | pr_debug("Can't invert tuple.\n"); |
9fb9cbb1 YK |
794 | return NULL; |
795 | } | |
796 | ||
99f07e91 CG |
797 | ct = __nf_conntrack_alloc(net, zone, tuple, &repl_tuple, GFP_ATOMIC, |
798 | hash); | |
0a9ee813 | 799 | if (IS_ERR(ct)) |
c88130bc | 800 | return (struct nf_conntrack_tuple_hash *)ct; |
9fb9cbb1 | 801 | |
60b5f8f7 PNA |
802 | timeout_ext = tmpl ? nf_ct_timeout_find(tmpl) : NULL; |
803 | if (timeout_ext) | |
804 | timeouts = NF_CT_TIMEOUT_EXT_DATA(timeout_ext); | |
805 | else | |
806 | timeouts = l4proto->get_timeouts(net); | |
807 | ||
2c8503f5 | 808 | if (!l4proto->new(ct, skb, dataoff, timeouts)) { |
c88130bc | 809 | nf_conntrack_free(ct); |
0d53778e | 810 | pr_debug("init conntrack: can't track with proto module\n"); |
9fb9cbb1 YK |
811 | return NULL; |
812 | } | |
813 | ||
60b5f8f7 PNA |
814 | if (timeout_ext) |
815 | nf_ct_timeout_ext_add(ct, timeout_ext->timeout, GFP_ATOMIC); | |
816 | ||
58401572 | 817 | nf_ct_acct_ext_add(ct, GFP_ATOMIC); |
a992ca2a | 818 | nf_ct_tstamp_ext_add(ct, GFP_ATOMIC); |
b2a15a60 PM |
819 | |
820 | ecache = tmpl ? nf_ct_ecache_find(tmpl) : NULL; | |
821 | nf_ct_ecache_ext_add(ct, ecache ? ecache->ctmask : 0, | |
822 | ecache ? ecache->expmask : 0, | |
823 | GFP_ATOMIC); | |
58401572 | 824 | |
f8ba1aff | 825 | spin_lock_bh(&nf_conntrack_lock); |
5d0aa2cc | 826 | exp = nf_ct_find_expectation(net, zone, tuple); |
9fb9cbb1 | 827 | if (exp) { |
0d53778e | 828 | pr_debug("conntrack: expectation arrives ct=%p exp=%p\n", |
c88130bc | 829 | ct, exp); |
9fb9cbb1 | 830 | /* Welcome, Mr. Bond. We've been expecting you... */ |
c88130bc PM |
831 | __set_bit(IPS_EXPECTED_BIT, &ct->status); |
832 | ct->master = exp->master; | |
ceceae1b | 833 | if (exp->helper) { |
1afc5679 PNA |
834 | help = nf_ct_helper_ext_add(ct, exp->helper, |
835 | GFP_ATOMIC); | |
ceceae1b | 836 | if (help) |
cf778b00 | 837 | rcu_assign_pointer(help->helper, exp->helper); |
ceceae1b YK |
838 | } |
839 | ||
9fb9cbb1 | 840 | #ifdef CONFIG_NF_CONNTRACK_MARK |
c88130bc | 841 | ct->mark = exp->master->mark; |
7c9728c3 JM |
842 | #endif |
843 | #ifdef CONFIG_NF_CONNTRACK_SECMARK | |
c88130bc | 844 | ct->secmark = exp->master->secmark; |
9fb9cbb1 | 845 | #endif |
c88130bc | 846 | nf_conntrack_get(&ct->master->ct_general); |
0d55af87 | 847 | NF_CT_STAT_INC(net, expect_new); |
22e7410b | 848 | } else { |
b2a15a60 | 849 | __nf_ct_try_assign_helper(ct, tmpl, GFP_ATOMIC); |
0d55af87 | 850 | NF_CT_STAT_INC(net, new); |
22e7410b | 851 | } |
9fb9cbb1 YK |
852 | |
853 | /* Overload tuple linked list to put us in unconfirmed list. */ | |
ea781f19 | 854 | hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, |
63c9a262 | 855 | &net->ct.unconfirmed); |
9fb9cbb1 | 856 | |
f8ba1aff | 857 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
858 | |
859 | if (exp) { | |
860 | if (exp->expectfn) | |
c88130bc | 861 | exp->expectfn(ct, exp); |
6823645d | 862 | nf_ct_expect_put(exp); |
9fb9cbb1 YK |
863 | } |
864 | ||
c88130bc | 865 | return &ct->tuplehash[IP_CT_DIR_ORIGINAL]; |
9fb9cbb1 YK |
866 | } |
867 | ||
868 | /* On success, returns conntrack ptr, sets skb->nfct and ctinfo */ | |
869 | static inline struct nf_conn * | |
b2a15a60 | 870 | resolve_normal_ct(struct net *net, struct nf_conn *tmpl, |
a702a65f | 871 | struct sk_buff *skb, |
9fb9cbb1 YK |
872 | unsigned int dataoff, |
873 | u_int16_t l3num, | |
874 | u_int8_t protonum, | |
875 | struct nf_conntrack_l3proto *l3proto, | |
605dcad6 | 876 | struct nf_conntrack_l4proto *l4proto, |
9fb9cbb1 | 877 | int *set_reply, |
60b5f8f7 | 878 | enum ip_conntrack_info *ctinfo) |
9fb9cbb1 YK |
879 | { |
880 | struct nf_conntrack_tuple tuple; | |
881 | struct nf_conntrack_tuple_hash *h; | |
882 | struct nf_conn *ct; | |
5d0aa2cc | 883 | u16 zone = tmpl ? nf_ct_zone(tmpl) : NF_CT_DEFAULT_ZONE; |
99f07e91 | 884 | u32 hash; |
9fb9cbb1 | 885 | |
bbe735e4 | 886 | if (!nf_ct_get_tuple(skb, skb_network_offset(skb), |
9fb9cbb1 | 887 | dataoff, l3num, protonum, &tuple, l3proto, |
605dcad6 | 888 | l4proto)) { |
0d53778e | 889 | pr_debug("resolve_normal_ct: Can't get tuple\n"); |
9fb9cbb1 YK |
890 | return NULL; |
891 | } | |
892 | ||
893 | /* look for tuple match */ | |
99f07e91 CG |
894 | hash = hash_conntrack_raw(&tuple, zone); |
895 | h = __nf_conntrack_find_get(net, zone, &tuple, hash); | |
9fb9cbb1 | 896 | if (!h) { |
b2a15a60 | 897 | h = init_conntrack(net, tmpl, &tuple, l3proto, l4proto, |
60b5f8f7 | 898 | skb, dataoff, hash); |
9fb9cbb1 YK |
899 | if (!h) |
900 | return NULL; | |
901 | if (IS_ERR(h)) | |
902 | return (void *)h; | |
903 | } | |
904 | ct = nf_ct_tuplehash_to_ctrack(h); | |
905 | ||
906 | /* It exists; we have (non-exclusive) reference. */ | |
907 | if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) { | |
fb048833 | 908 | *ctinfo = IP_CT_ESTABLISHED_REPLY; |
9fb9cbb1 YK |
909 | /* Please set reply bit if this packet OK */ |
910 | *set_reply = 1; | |
911 | } else { | |
912 | /* Once we've had two way comms, always ESTABLISHED. */ | |
913 | if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { | |
0d53778e | 914 | pr_debug("nf_conntrack_in: normal packet for %p\n", ct); |
9fb9cbb1 YK |
915 | *ctinfo = IP_CT_ESTABLISHED; |
916 | } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) { | |
0d53778e PM |
917 | pr_debug("nf_conntrack_in: related packet for %p\n", |
918 | ct); | |
9fb9cbb1 YK |
919 | *ctinfo = IP_CT_RELATED; |
920 | } else { | |
0d53778e | 921 | pr_debug("nf_conntrack_in: new packet for %p\n", ct); |
9fb9cbb1 YK |
922 | *ctinfo = IP_CT_NEW; |
923 | } | |
924 | *set_reply = 0; | |
925 | } | |
926 | skb->nfct = &ct->ct_general; | |
927 | skb->nfctinfo = *ctinfo; | |
928 | return ct; | |
929 | } | |
930 | ||
931 | unsigned int | |
a702a65f AD |
932 | nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum, |
933 | struct sk_buff *skb) | |
9fb9cbb1 | 934 | { |
b2a15a60 | 935 | struct nf_conn *ct, *tmpl = NULL; |
9fb9cbb1 YK |
936 | enum ip_conntrack_info ctinfo; |
937 | struct nf_conntrack_l3proto *l3proto; | |
605dcad6 | 938 | struct nf_conntrack_l4proto *l4proto; |
2c8503f5 | 939 | unsigned int *timeouts; |
9fb9cbb1 YK |
940 | unsigned int dataoff; |
941 | u_int8_t protonum; | |
942 | int set_reply = 0; | |
943 | int ret; | |
944 | ||
3db05fea | 945 | if (skb->nfct) { |
b2a15a60 PM |
946 | /* Previously seen (loopback or untracked)? Ignore. */ |
947 | tmpl = (struct nf_conn *)skb->nfct; | |
948 | if (!nf_ct_is_template(tmpl)) { | |
949 | NF_CT_STAT_INC_ATOMIC(net, ignore); | |
950 | return NF_ACCEPT; | |
951 | } | |
952 | skb->nfct = NULL; | |
9fb9cbb1 YK |
953 | } |
954 | ||
923f4902 | 955 | /* rcu_read_lock()ed by nf_hook_slow */ |
76108cea | 956 | l3proto = __nf_ct_l3proto_find(pf); |
3db05fea | 957 | ret = l3proto->get_l4proto(skb, skb_network_offset(skb), |
ffc30690 YK |
958 | &dataoff, &protonum); |
959 | if (ret <= 0) { | |
25985edc | 960 | pr_debug("not prepared to track yet or error occurred\n"); |
0d55af87 AD |
961 | NF_CT_STAT_INC_ATOMIC(net, error); |
962 | NF_CT_STAT_INC_ATOMIC(net, invalid); | |
b2a15a60 PM |
963 | ret = -ret; |
964 | goto out; | |
9fb9cbb1 YK |
965 | } |
966 | ||
76108cea | 967 | l4proto = __nf_ct_l4proto_find(pf, protonum); |
9fb9cbb1 YK |
968 | |
969 | /* It may be an special packet, error, unclean... | |
970 | * inverse of the return code tells to the netfilter | |
971 | * core what to do with the packet. */ | |
74c51a14 | 972 | if (l4proto->error != NULL) { |
8fea97ec PM |
973 | ret = l4proto->error(net, tmpl, skb, dataoff, &ctinfo, |
974 | pf, hooknum); | |
74c51a14 | 975 | if (ret <= 0) { |
0d55af87 AD |
976 | NF_CT_STAT_INC_ATOMIC(net, error); |
977 | NF_CT_STAT_INC_ATOMIC(net, invalid); | |
b2a15a60 PM |
978 | ret = -ret; |
979 | goto out; | |
74c51a14 | 980 | } |
88ed01d1 PNA |
981 | /* ICMP[v6] protocol trackers may assign one conntrack. */ |
982 | if (skb->nfct) | |
983 | goto out; | |
9fb9cbb1 YK |
984 | } |
985 | ||
b2a15a60 | 986 | ct = resolve_normal_ct(net, tmpl, skb, dataoff, pf, protonum, |
60b5f8f7 | 987 | l3proto, l4proto, &set_reply, &ctinfo); |
9fb9cbb1 YK |
988 | if (!ct) { |
989 | /* Not valid part of a connection */ | |
0d55af87 | 990 | NF_CT_STAT_INC_ATOMIC(net, invalid); |
b2a15a60 PM |
991 | ret = NF_ACCEPT; |
992 | goto out; | |
9fb9cbb1 YK |
993 | } |
994 | ||
995 | if (IS_ERR(ct)) { | |
996 | /* Too stressed to deal. */ | |
0d55af87 | 997 | NF_CT_STAT_INC_ATOMIC(net, drop); |
b2a15a60 PM |
998 | ret = NF_DROP; |
999 | goto out; | |
9fb9cbb1 YK |
1000 | } |
1001 | ||
3db05fea | 1002 | NF_CT_ASSERT(skb->nfct); |
9fb9cbb1 | 1003 | |
60b5f8f7 | 1004 | /* Decide what timeout policy we want to apply to this flow. */ |
84b5ee93 | 1005 | timeouts = nf_ct_timeout_lookup(net, ct, l4proto); |
60b5f8f7 | 1006 | |
2c8503f5 | 1007 | ret = l4proto->packet(ct, skb, dataoff, ctinfo, pf, hooknum, timeouts); |
ec8d5409 | 1008 | if (ret <= 0) { |
9fb9cbb1 YK |
1009 | /* Invalid: inverse of the return code tells |
1010 | * the netfilter core what to do */ | |
0d53778e | 1011 | pr_debug("nf_conntrack_in: Can't track with proto module\n"); |
3db05fea HX |
1012 | nf_conntrack_put(skb->nfct); |
1013 | skb->nfct = NULL; | |
0d55af87 | 1014 | NF_CT_STAT_INC_ATOMIC(net, invalid); |
7d1e0459 PNA |
1015 | if (ret == -NF_DROP) |
1016 | NF_CT_STAT_INC_ATOMIC(net, drop); | |
b2a15a60 PM |
1017 | ret = -ret; |
1018 | goto out; | |
9fb9cbb1 YK |
1019 | } |
1020 | ||
1021 | if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status)) | |
858b3133 | 1022 | nf_conntrack_event_cache(IPCT_REPLY, ct); |
b2a15a60 | 1023 | out: |
c3174286 PNA |
1024 | if (tmpl) { |
1025 | /* Special case: we have to repeat this hook, assign the | |
1026 | * template again to this packet. We assume that this packet | |
1027 | * has no conntrack assigned. This is used by nf_ct_tcp. */ | |
1028 | if (ret == NF_REPEAT) | |
1029 | skb->nfct = (struct nf_conntrack *)tmpl; | |
1030 | else | |
1031 | nf_ct_put(tmpl); | |
1032 | } | |
9fb9cbb1 YK |
1033 | |
1034 | return ret; | |
1035 | } | |
13b18339 | 1036 | EXPORT_SYMBOL_GPL(nf_conntrack_in); |
9fb9cbb1 | 1037 | |
5f2b4c90 JE |
1038 | bool nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse, |
1039 | const struct nf_conntrack_tuple *orig) | |
9fb9cbb1 | 1040 | { |
5f2b4c90 | 1041 | bool ret; |
923f4902 PM |
1042 | |
1043 | rcu_read_lock(); | |
1044 | ret = nf_ct_invert_tuple(inverse, orig, | |
1045 | __nf_ct_l3proto_find(orig->src.l3num), | |
1046 | __nf_ct_l4proto_find(orig->src.l3num, | |
1047 | orig->dst.protonum)); | |
1048 | rcu_read_unlock(); | |
1049 | return ret; | |
9fb9cbb1 | 1050 | } |
13b18339 | 1051 | EXPORT_SYMBOL_GPL(nf_ct_invert_tuplepr); |
9fb9cbb1 | 1052 | |
5b1158e9 JK |
1053 | /* Alter reply tuple (maybe alter helper). This is for NAT, and is |
1054 | implicitly racy: see __nf_conntrack_confirm */ | |
1055 | void nf_conntrack_alter_reply(struct nf_conn *ct, | |
1056 | const struct nf_conntrack_tuple *newreply) | |
1057 | { | |
1058 | struct nf_conn_help *help = nfct_help(ct); | |
1059 | ||
5b1158e9 JK |
1060 | /* Should be unconfirmed, so not in hash table yet */ |
1061 | NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); | |
1062 | ||
0d53778e | 1063 | pr_debug("Altering reply tuple of %p to ", ct); |
3c9fba65 | 1064 | nf_ct_dump_tuple(newreply); |
5b1158e9 JK |
1065 | |
1066 | ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply; | |
ef1a5a50 | 1067 | if (ct->master || (help && !hlist_empty(&help->expectations))) |
c52fbb41 | 1068 | return; |
ceceae1b | 1069 | |
c52fbb41 | 1070 | rcu_read_lock(); |
b2a15a60 | 1071 | __nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC); |
c52fbb41 | 1072 | rcu_read_unlock(); |
5b1158e9 | 1073 | } |
13b18339 | 1074 | EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply); |
5b1158e9 | 1075 | |
9fb9cbb1 YK |
1076 | /* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */ |
1077 | void __nf_ct_refresh_acct(struct nf_conn *ct, | |
1078 | enum ip_conntrack_info ctinfo, | |
1079 | const struct sk_buff *skb, | |
1080 | unsigned long extra_jiffies, | |
1081 | int do_acct) | |
1082 | { | |
9fb9cbb1 YK |
1083 | NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct); |
1084 | NF_CT_ASSERT(skb); | |
1085 | ||
997ae831 | 1086 | /* Only update if this is not a fixed timeout */ |
47d95045 PM |
1087 | if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status)) |
1088 | goto acct; | |
997ae831 | 1089 | |
9fb9cbb1 YK |
1090 | /* If not in hash table, timer will not be active yet */ |
1091 | if (!nf_ct_is_confirmed(ct)) { | |
1092 | ct->timeout.expires = extra_jiffies; | |
9fb9cbb1 | 1093 | } else { |
be00c8e4 MJ |
1094 | unsigned long newtime = jiffies + extra_jiffies; |
1095 | ||
1096 | /* Only update the timeout if the new timeout is at least | |
1097 | HZ jiffies from the old timeout. Need del_timer for race | |
1098 | avoidance (may already be dying). */ | |
65cb9fda PM |
1099 | if (newtime - ct->timeout.expires >= HZ) |
1100 | mod_timer_pending(&ct->timeout, newtime); | |
9fb9cbb1 YK |
1101 | } |
1102 | ||
47d95045 | 1103 | acct: |
9fb9cbb1 | 1104 | if (do_acct) { |
58401572 | 1105 | struct nf_conn_counter *acct; |
3ffd5eeb | 1106 | |
58401572 KPO |
1107 | acct = nf_conn_acct_find(ct); |
1108 | if (acct) { | |
b3e0bfa7 ED |
1109 | atomic64_inc(&acct[CTINFO2DIR(ctinfo)].packets); |
1110 | atomic64_add(skb->len, &acct[CTINFO2DIR(ctinfo)].bytes); | |
58401572 | 1111 | } |
9fb9cbb1 | 1112 | } |
9fb9cbb1 | 1113 | } |
13b18339 | 1114 | EXPORT_SYMBOL_GPL(__nf_ct_refresh_acct); |
9fb9cbb1 | 1115 | |
4c889498 DM |
1116 | bool __nf_ct_kill_acct(struct nf_conn *ct, |
1117 | enum ip_conntrack_info ctinfo, | |
1118 | const struct sk_buff *skb, | |
1119 | int do_acct) | |
51091764 | 1120 | { |
718d4ad9 | 1121 | if (do_acct) { |
58401572 KPO |
1122 | struct nf_conn_counter *acct; |
1123 | ||
58401572 KPO |
1124 | acct = nf_conn_acct_find(ct); |
1125 | if (acct) { | |
b3e0bfa7 ED |
1126 | atomic64_inc(&acct[CTINFO2DIR(ctinfo)].packets); |
1127 | atomic64_add(skb->len - skb_network_offset(skb), | |
1128 | &acct[CTINFO2DIR(ctinfo)].bytes); | |
58401572 | 1129 | } |
718d4ad9 | 1130 | } |
58401572 | 1131 | |
4c889498 | 1132 | if (del_timer(&ct->timeout)) { |
51091764 | 1133 | ct->timeout.function((unsigned long)ct); |
4c889498 DM |
1134 | return true; |
1135 | } | |
1136 | return false; | |
51091764 | 1137 | } |
718d4ad9 | 1138 | EXPORT_SYMBOL_GPL(__nf_ct_kill_acct); |
51091764 | 1139 | |
5d0aa2cc PM |
1140 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1141 | static struct nf_ct_ext_type nf_ct_zone_extend __read_mostly = { | |
1142 | .len = sizeof(struct nf_conntrack_zone), | |
1143 | .align = __alignof__(struct nf_conntrack_zone), | |
1144 | .id = NF_CT_EXT_ZONE, | |
1145 | }; | |
1146 | #endif | |
1147 | ||
c0cd1156 | 1148 | #if IS_ENABLED(CONFIG_NF_CT_NETLINK) |
c1d10adb PNA |
1149 | |
1150 | #include <linux/netfilter/nfnetlink.h> | |
1151 | #include <linux/netfilter/nfnetlink_conntrack.h> | |
57b47a53 IM |
1152 | #include <linux/mutex.h> |
1153 | ||
c1d10adb PNA |
1154 | /* Generic function for tcp/udp/sctp/dccp and alike. This needs to be |
1155 | * in ip_conntrack_core, since we don't want the protocols to autoload | |
1156 | * or depend on ctnetlink */ | |
fdf70832 | 1157 | int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, |
c1d10adb PNA |
1158 | const struct nf_conntrack_tuple *tuple) |
1159 | { | |
bae65be8 DM |
1160 | if (nla_put_be16(skb, CTA_PROTO_SRC_PORT, tuple->src.u.tcp.port) || |
1161 | nla_put_be16(skb, CTA_PROTO_DST_PORT, tuple->dst.u.tcp.port)) | |
1162 | goto nla_put_failure; | |
c1d10adb PNA |
1163 | return 0; |
1164 | ||
df6fb868 | 1165 | nla_put_failure: |
c1d10adb PNA |
1166 | return -1; |
1167 | } | |
fdf70832 | 1168 | EXPORT_SYMBOL_GPL(nf_ct_port_tuple_to_nlattr); |
c1d10adb | 1169 | |
f73e924c PM |
1170 | const struct nla_policy nf_ct_port_nla_policy[CTA_PROTO_MAX+1] = { |
1171 | [CTA_PROTO_SRC_PORT] = { .type = NLA_U16 }, | |
1172 | [CTA_PROTO_DST_PORT] = { .type = NLA_U16 }, | |
c1d10adb | 1173 | }; |
f73e924c | 1174 | EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy); |
c1d10adb | 1175 | |
fdf70832 | 1176 | int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], |
c1d10adb PNA |
1177 | struct nf_conntrack_tuple *t) |
1178 | { | |
df6fb868 | 1179 | if (!tb[CTA_PROTO_SRC_PORT] || !tb[CTA_PROTO_DST_PORT]) |
c1d10adb PNA |
1180 | return -EINVAL; |
1181 | ||
77236b6e PM |
1182 | t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]); |
1183 | t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]); | |
c1d10adb PNA |
1184 | |
1185 | return 0; | |
1186 | } | |
fdf70832 | 1187 | EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_to_tuple); |
5c0de29d HE |
1188 | |
1189 | int nf_ct_port_nlattr_tuple_size(void) | |
1190 | { | |
1191 | return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1); | |
1192 | } | |
1193 | EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_tuple_size); | |
c1d10adb PNA |
1194 | #endif |
1195 | ||
9fb9cbb1 | 1196 | /* Used by ipt_REJECT and ip6t_REJECT. */ |
b334aadc | 1197 | static void nf_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb) |
9fb9cbb1 YK |
1198 | { |
1199 | struct nf_conn *ct; | |
1200 | enum ip_conntrack_info ctinfo; | |
1201 | ||
1202 | /* This ICMP is in reverse direction to the packet which caused it */ | |
1203 | ct = nf_ct_get(skb, &ctinfo); | |
1204 | if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) | |
fb048833 | 1205 | ctinfo = IP_CT_RELATED_REPLY; |
9fb9cbb1 YK |
1206 | else |
1207 | ctinfo = IP_CT_RELATED; | |
1208 | ||
1209 | /* Attach to new skbuff, and increment count */ | |
1210 | nskb->nfct = &ct->ct_general; | |
1211 | nskb->nfctinfo = ctinfo; | |
1212 | nf_conntrack_get(nskb->nfct); | |
1213 | } | |
1214 | ||
9fb9cbb1 | 1215 | /* Bring out ya dead! */ |
df0933dc | 1216 | static struct nf_conn * |
400dad39 | 1217 | get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data), |
9fb9cbb1 YK |
1218 | void *data, unsigned int *bucket) |
1219 | { | |
df0933dc PM |
1220 | struct nf_conntrack_tuple_hash *h; |
1221 | struct nf_conn *ct; | |
ea781f19 | 1222 | struct hlist_nulls_node *n; |
9fb9cbb1 | 1223 | |
f8ba1aff | 1224 | spin_lock_bh(&nf_conntrack_lock); |
d696c7bd | 1225 | for (; *bucket < net->ct.htable_size; (*bucket)++) { |
ea781f19 | 1226 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[*bucket], hnnode) { |
b0cdb1d9 PM |
1227 | if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL) |
1228 | continue; | |
df0933dc PM |
1229 | ct = nf_ct_tuplehash_to_ctrack(h); |
1230 | if (iter(ct, data)) | |
1231 | goto found; | |
1232 | } | |
601e68e1 | 1233 | } |
ea781f19 | 1234 | hlist_nulls_for_each_entry(h, n, &net->ct.unconfirmed, hnnode) { |
df0933dc PM |
1235 | ct = nf_ct_tuplehash_to_ctrack(h); |
1236 | if (iter(ct, data)) | |
ec68e97d | 1237 | set_bit(IPS_DYING_BIT, &ct->status); |
df0933dc | 1238 | } |
f8ba1aff | 1239 | spin_unlock_bh(&nf_conntrack_lock); |
df0933dc PM |
1240 | return NULL; |
1241 | found: | |
c073e3fa | 1242 | atomic_inc(&ct->ct_general.use); |
f8ba1aff | 1243 | spin_unlock_bh(&nf_conntrack_lock); |
df0933dc | 1244 | return ct; |
9fb9cbb1 YK |
1245 | } |
1246 | ||
400dad39 AD |
1247 | void nf_ct_iterate_cleanup(struct net *net, |
1248 | int (*iter)(struct nf_conn *i, void *data), | |
1249 | void *data) | |
9fb9cbb1 | 1250 | { |
df0933dc | 1251 | struct nf_conn *ct; |
9fb9cbb1 YK |
1252 | unsigned int bucket = 0; |
1253 | ||
400dad39 | 1254 | while ((ct = get_next_corpse(net, iter, data, &bucket)) != NULL) { |
9fb9cbb1 YK |
1255 | /* Time to push up daises... */ |
1256 | if (del_timer(&ct->timeout)) | |
1257 | death_by_timeout((unsigned long)ct); | |
1258 | /* ... else the timer will get him soon. */ | |
1259 | ||
1260 | nf_ct_put(ct); | |
1261 | } | |
1262 | } | |
13b18339 | 1263 | EXPORT_SYMBOL_GPL(nf_ct_iterate_cleanup); |
9fb9cbb1 | 1264 | |
19abb7b0 PNA |
1265 | struct __nf_ct_flush_report { |
1266 | u32 pid; | |
1267 | int report; | |
1268 | }; | |
1269 | ||
274d383b | 1270 | static int kill_report(struct nf_conn *i, void *data) |
9fb9cbb1 | 1271 | { |
19abb7b0 | 1272 | struct __nf_ct_flush_report *fr = (struct __nf_ct_flush_report *)data; |
a992ca2a PNA |
1273 | struct nf_conn_tstamp *tstamp; |
1274 | ||
1275 | tstamp = nf_conn_tstamp_find(i); | |
1276 | if (tstamp && tstamp->stop == 0) | |
1277 | tstamp->stop = ktime_to_ns(ktime_get_real()); | |
19abb7b0 | 1278 | |
dd7669a9 PNA |
1279 | /* If we fail to deliver the event, death_by_timeout() will retry */ |
1280 | if (nf_conntrack_event_report(IPCT_DESTROY, i, | |
1281 | fr->pid, fr->report) < 0) | |
1282 | return 1; | |
1283 | ||
1284 | /* Avoid the delivery of the destroy event in death_by_timeout(). */ | |
1285 | set_bit(IPS_DYING_BIT, &i->status); | |
9fb9cbb1 YK |
1286 | return 1; |
1287 | } | |
1288 | ||
274d383b PNA |
1289 | static int kill_all(struct nf_conn *i, void *data) |
1290 | { | |
1291 | return 1; | |
1292 | } | |
1293 | ||
d862a662 | 1294 | void nf_ct_free_hashtable(void *hash, unsigned int size) |
9fb9cbb1 | 1295 | { |
d862a662 | 1296 | if (is_vmalloc_addr(hash)) |
9fb9cbb1 YK |
1297 | vfree(hash); |
1298 | else | |
601e68e1 | 1299 | free_pages((unsigned long)hash, |
f205c5e0 | 1300 | get_order(sizeof(struct hlist_head) * size)); |
9fb9cbb1 | 1301 | } |
ac565e5f | 1302 | EXPORT_SYMBOL_GPL(nf_ct_free_hashtable); |
9fb9cbb1 | 1303 | |
274d383b | 1304 | void nf_conntrack_flush_report(struct net *net, u32 pid, int report) |
c1d10adb | 1305 | { |
19abb7b0 PNA |
1306 | struct __nf_ct_flush_report fr = { |
1307 | .pid = pid, | |
1308 | .report = report, | |
1309 | }; | |
274d383b | 1310 | nf_ct_iterate_cleanup(net, kill_report, &fr); |
c1d10adb | 1311 | } |
274d383b | 1312 | EXPORT_SYMBOL_GPL(nf_conntrack_flush_report); |
c1d10adb | 1313 | |
ee254fa4 | 1314 | static void nf_ct_release_dying_list(struct net *net) |
dd7669a9 PNA |
1315 | { |
1316 | struct nf_conntrack_tuple_hash *h; | |
1317 | struct nf_conn *ct; | |
1318 | struct hlist_nulls_node *n; | |
1319 | ||
1320 | spin_lock_bh(&nf_conntrack_lock); | |
ee254fa4 | 1321 | hlist_nulls_for_each_entry(h, n, &net->ct.dying, hnnode) { |
dd7669a9 PNA |
1322 | ct = nf_ct_tuplehash_to_ctrack(h); |
1323 | /* never fails to remove them, no listeners at this point */ | |
1324 | nf_ct_kill(ct); | |
1325 | } | |
1326 | spin_unlock_bh(&nf_conntrack_lock); | |
1327 | } | |
1328 | ||
b3c5163f ED |
1329 | static int untrack_refs(void) |
1330 | { | |
1331 | int cnt = 0, cpu; | |
1332 | ||
1333 | for_each_possible_cpu(cpu) { | |
1334 | struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu); | |
1335 | ||
1336 | cnt += atomic_read(&ct->ct_general.use) - 1; | |
1337 | } | |
1338 | return cnt; | |
1339 | } | |
1340 | ||
08f6547d | 1341 | static void nf_conntrack_cleanup_init_net(void) |
9fb9cbb1 | 1342 | { |
b3c5163f | 1343 | while (untrack_refs() > 0) |
9edd7ca0 PM |
1344 | schedule(); |
1345 | ||
5d0aa2cc PM |
1346 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1347 | nf_ct_extend_unregister(&nf_ct_zone_extend); | |
1348 | #endif | |
08f6547d | 1349 | } |
9fb9cbb1 | 1350 | |
08f6547d AD |
1351 | static void nf_conntrack_cleanup_net(struct net *net) |
1352 | { | |
9fb9cbb1 | 1353 | i_see_dead_people: |
274d383b | 1354 | nf_ct_iterate_cleanup(net, kill_all, NULL); |
ee254fa4 | 1355 | nf_ct_release_dying_list(net); |
49ac8713 | 1356 | if (atomic_read(&net->ct.count) != 0) { |
9fb9cbb1 YK |
1357 | schedule(); |
1358 | goto i_see_dead_people; | |
1359 | } | |
1360 | ||
d862a662 | 1361 | nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size); |
a9006892 | 1362 | nf_conntrack_helper_fini(net); |
dd705072 | 1363 | nf_conntrack_timeout_fini(net); |
a0891aa6 | 1364 | nf_conntrack_ecache_fini(net); |
fe8f661f | 1365 | nf_conntrack_tstamp_fini(net); |
d716a4df | 1366 | nf_conntrack_acct_fini(net); |
9b03f38d | 1367 | nf_conntrack_expect_fini(net); |
5b3501fa ED |
1368 | kmem_cache_destroy(net->ct.nf_conntrack_cachep); |
1369 | kfree(net->ct.slabname); | |
0d55af87 | 1370 | free_percpu(net->ct.stat); |
08f6547d AD |
1371 | } |
1372 | ||
1373 | /* Mishearing the voices in his head, our hero wonders how he's | |
1374 | supposed to kill the mall. */ | |
1375 | void nf_conntrack_cleanup(struct net *net) | |
1376 | { | |
1377 | if (net_eq(net, &init_net)) | |
a9b3cd7f | 1378 | RCU_INIT_POINTER(ip_ct_attach, NULL); |
08f6547d AD |
1379 | |
1380 | /* This makes sure all current packets have passed through | |
1381 | netfilter framework. Roll on, two-stage module | |
1382 | delete... */ | |
1383 | synchronize_net(); | |
15f585bd | 1384 | nf_conntrack_proto_fini(net); |
08f6547d AD |
1385 | nf_conntrack_cleanup_net(net); |
1386 | ||
1387 | if (net_eq(net, &init_net)) { | |
a9b3cd7f | 1388 | RCU_INIT_POINTER(nf_ct_destroy, NULL); |
08f6547d AD |
1389 | nf_conntrack_cleanup_init_net(); |
1390 | } | |
9fb9cbb1 YK |
1391 | } |
1392 | ||
d862a662 | 1393 | void *nf_ct_alloc_hashtable(unsigned int *sizep, int nulls) |
9fb9cbb1 | 1394 | { |
ea781f19 ED |
1395 | struct hlist_nulls_head *hash; |
1396 | unsigned int nr_slots, i; | |
1397 | size_t sz; | |
9fb9cbb1 | 1398 | |
ea781f19 ED |
1399 | BUILD_BUG_ON(sizeof(struct hlist_nulls_head) != sizeof(struct hlist_head)); |
1400 | nr_slots = *sizep = roundup(*sizep, PAGE_SIZE / sizeof(struct hlist_nulls_head)); | |
1401 | sz = nr_slots * sizeof(struct hlist_nulls_head); | |
1402 | hash = (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, | |
1403 | get_order(sz)); | |
601e68e1 | 1404 | if (!hash) { |
9fb9cbb1 | 1405 | printk(KERN_WARNING "nf_conntrack: falling back to vmalloc.\n"); |
966567b7 | 1406 | hash = vzalloc(sz); |
9fb9cbb1 YK |
1407 | } |
1408 | ||
ea781f19 ED |
1409 | if (hash && nulls) |
1410 | for (i = 0; i < nr_slots; i++) | |
1411 | INIT_HLIST_NULLS_HEAD(&hash[i], i); | |
9fb9cbb1 YK |
1412 | |
1413 | return hash; | |
1414 | } | |
ac565e5f | 1415 | EXPORT_SYMBOL_GPL(nf_ct_alloc_hashtable); |
9fb9cbb1 | 1416 | |
fae718dd | 1417 | int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp) |
9fb9cbb1 | 1418 | { |
d862a662 | 1419 | int i, bucket; |
96eb24d7 | 1420 | unsigned int hashsize, old_size; |
ea781f19 | 1421 | struct hlist_nulls_head *hash, *old_hash; |
9fb9cbb1 | 1422 | struct nf_conntrack_tuple_hash *h; |
5d0aa2cc | 1423 | struct nf_conn *ct; |
9fb9cbb1 | 1424 | |
d696c7bd PM |
1425 | if (current->nsproxy->net_ns != &init_net) |
1426 | return -EOPNOTSUPP; | |
1427 | ||
9fb9cbb1 YK |
1428 | /* On boot, we can set this without any fancy locking. */ |
1429 | if (!nf_conntrack_htable_size) | |
1430 | return param_set_uint(val, kp); | |
1431 | ||
96eb24d7 | 1432 | hashsize = simple_strtoul(val, NULL, 0); |
9fb9cbb1 YK |
1433 | if (!hashsize) |
1434 | return -EINVAL; | |
1435 | ||
d862a662 | 1436 | hash = nf_ct_alloc_hashtable(&hashsize, 1); |
9fb9cbb1 YK |
1437 | if (!hash) |
1438 | return -ENOMEM; | |
1439 | ||
76507f69 PM |
1440 | /* Lookups in the old hash might happen in parallel, which means we |
1441 | * might get false negatives during connection lookup. New connections | |
1442 | * created because of a false negative won't make it into the hash | |
1443 | * though since that required taking the lock. | |
1444 | */ | |
f8ba1aff | 1445 | spin_lock_bh(&nf_conntrack_lock); |
d696c7bd | 1446 | for (i = 0; i < init_net.ct.htable_size; i++) { |
ea781f19 ED |
1447 | while (!hlist_nulls_empty(&init_net.ct.hash[i])) { |
1448 | h = hlist_nulls_entry(init_net.ct.hash[i].first, | |
1449 | struct nf_conntrack_tuple_hash, hnnode); | |
5d0aa2cc | 1450 | ct = nf_ct_tuplehash_to_ctrack(h); |
ea781f19 | 1451 | hlist_nulls_del_rcu(&h->hnnode); |
5d0aa2cc | 1452 | bucket = __hash_conntrack(&h->tuple, nf_ct_zone(ct), |
99f07e91 | 1453 | hashsize); |
ea781f19 | 1454 | hlist_nulls_add_head_rcu(&h->hnnode, &hash[bucket]); |
9fb9cbb1 YK |
1455 | } |
1456 | } | |
d696c7bd | 1457 | old_size = init_net.ct.htable_size; |
400dad39 | 1458 | old_hash = init_net.ct.hash; |
9fb9cbb1 | 1459 | |
d696c7bd | 1460 | init_net.ct.htable_size = nf_conntrack_htable_size = hashsize; |
400dad39 | 1461 | init_net.ct.hash = hash; |
f8ba1aff | 1462 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 | 1463 | |
d862a662 | 1464 | nf_ct_free_hashtable(old_hash, old_size); |
9fb9cbb1 YK |
1465 | return 0; |
1466 | } | |
fae718dd | 1467 | EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize); |
9fb9cbb1 | 1468 | |
fae718dd | 1469 | module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint, |
9fb9cbb1 YK |
1470 | &nf_conntrack_htable_size, 0600); |
1471 | ||
5bfddbd4 ED |
1472 | void nf_ct_untracked_status_or(unsigned long bits) |
1473 | { | |
b3c5163f ED |
1474 | int cpu; |
1475 | ||
1476 | for_each_possible_cpu(cpu) | |
1477 | per_cpu(nf_conntrack_untracked, cpu).status |= bits; | |
5bfddbd4 ED |
1478 | } |
1479 | EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or); | |
1480 | ||
08f6547d | 1481 | static int nf_conntrack_init_init_net(void) |
9fb9cbb1 | 1482 | { |
f205c5e0 | 1483 | int max_factor = 8; |
b3c5163f | 1484 | int ret, cpu; |
9fb9cbb1 YK |
1485 | |
1486 | /* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB | |
f205c5e0 | 1487 | * machine has 512 buckets. >= 1GB machines have 16384 buckets. */ |
9fb9cbb1 YK |
1488 | if (!nf_conntrack_htable_size) { |
1489 | nf_conntrack_htable_size | |
4481374c | 1490 | = (((totalram_pages << PAGE_SHIFT) / 16384) |
f205c5e0 | 1491 | / sizeof(struct hlist_head)); |
4481374c | 1492 | if (totalram_pages > (1024 * 1024 * 1024 / PAGE_SIZE)) |
f205c5e0 PM |
1493 | nf_conntrack_htable_size = 16384; |
1494 | if (nf_conntrack_htable_size < 32) | |
1495 | nf_conntrack_htable_size = 32; | |
1496 | ||
1497 | /* Use a max. factor of four by default to get the same max as | |
1498 | * with the old struct list_heads. When a table size is given | |
1499 | * we use the old value of 8 to avoid reducing the max. | |
1500 | * entries. */ | |
1501 | max_factor = 4; | |
9fb9cbb1 | 1502 | } |
f205c5e0 | 1503 | nf_conntrack_max = max_factor * nf_conntrack_htable_size; |
8e5105a0 | 1504 | |
654d0fbd | 1505 | printk(KERN_INFO "nf_conntrack version %s (%u buckets, %d max)\n", |
8e5105a0 PM |
1506 | NF_CONNTRACK_VERSION, nf_conntrack_htable_size, |
1507 | nf_conntrack_max); | |
5d0aa2cc PM |
1508 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1509 | ret = nf_ct_extend_register(&nf_ct_zone_extend); | |
1510 | if (ret < 0) | |
1511 | goto err_extend; | |
1512 | #endif | |
9edd7ca0 | 1513 | /* Set up fake conntrack: to never be deleted, not in any hashes */ |
b3c5163f ED |
1514 | for_each_possible_cpu(cpu) { |
1515 | struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu); | |
b3c5163f ED |
1516 | write_pnet(&ct->ct_net, &init_net); |
1517 | atomic_set(&ct->ct_general.use, 1); | |
1518 | } | |
9edd7ca0 | 1519 | /* - and look it like as a confirmed connection */ |
5bfddbd4 | 1520 | nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED); |
08f6547d AD |
1521 | return 0; |
1522 | ||
5d0aa2cc PM |
1523 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1524 | err_extend: | |
a9006892 | 1525 | #endif |
08f6547d AD |
1526 | return ret; |
1527 | } | |
1528 | ||
8cc20198 ED |
1529 | /* |
1530 | * We need to use special "null" values, not used in hash table | |
1531 | */ | |
1532 | #define UNCONFIRMED_NULLS_VAL ((1<<30)+0) | |
1533 | #define DYING_NULLS_VAL ((1<<30)+1) | |
1534 | ||
08f6547d AD |
1535 | static int nf_conntrack_init_net(struct net *net) |
1536 | { | |
1537 | int ret; | |
ceceae1b | 1538 | |
08f6547d | 1539 | atomic_set(&net->ct.count, 0); |
8cc20198 ED |
1540 | INIT_HLIST_NULLS_HEAD(&net->ct.unconfirmed, UNCONFIRMED_NULLS_VAL); |
1541 | INIT_HLIST_NULLS_HEAD(&net->ct.dying, DYING_NULLS_VAL); | |
08f6547d AD |
1542 | net->ct.stat = alloc_percpu(struct ip_conntrack_stat); |
1543 | if (!net->ct.stat) { | |
1544 | ret = -ENOMEM; | |
1545 | goto err_stat; | |
1546 | } | |
5b3501fa ED |
1547 | |
1548 | net->ct.slabname = kasprintf(GFP_KERNEL, "nf_conntrack_%p", net); | |
1549 | if (!net->ct.slabname) { | |
1550 | ret = -ENOMEM; | |
1551 | goto err_slabname; | |
1552 | } | |
1553 | ||
1554 | net->ct.nf_conntrack_cachep = kmem_cache_create(net->ct.slabname, | |
1555 | sizeof(struct nf_conn), 0, | |
1556 | SLAB_DESTROY_BY_RCU, NULL); | |
1557 | if (!net->ct.nf_conntrack_cachep) { | |
1558 | printk(KERN_ERR "Unable to create nf_conn slab cache\n"); | |
1559 | ret = -ENOMEM; | |
1560 | goto err_cache; | |
1561 | } | |
d696c7bd PM |
1562 | |
1563 | net->ct.htable_size = nf_conntrack_htable_size; | |
d862a662 | 1564 | net->ct.hash = nf_ct_alloc_hashtable(&net->ct.htable_size, 1); |
08f6547d AD |
1565 | if (!net->ct.hash) { |
1566 | ret = -ENOMEM; | |
1567 | printk(KERN_ERR "Unable to create nf_conntrack_hash\n"); | |
1568 | goto err_hash; | |
1569 | } | |
1570 | ret = nf_conntrack_expect_init(net); | |
1571 | if (ret < 0) | |
1572 | goto err_expect; | |
d716a4df | 1573 | ret = nf_conntrack_acct_init(net); |
58401572 | 1574 | if (ret < 0) |
08f6547d | 1575 | goto err_acct; |
a992ca2a PNA |
1576 | ret = nf_conntrack_tstamp_init(net); |
1577 | if (ret < 0) | |
1578 | goto err_tstamp; | |
a0891aa6 PNA |
1579 | ret = nf_conntrack_ecache_init(net); |
1580 | if (ret < 0) | |
1581 | goto err_ecache; | |
dd705072 PNA |
1582 | ret = nf_conntrack_timeout_init(net); |
1583 | if (ret < 0) | |
1584 | goto err_timeout; | |
a9006892 EL |
1585 | ret = nf_conntrack_helper_init(net); |
1586 | if (ret < 0) | |
1587 | goto err_helper; | |
08f6547d | 1588 | return 0; |
a9006892 EL |
1589 | err_helper: |
1590 | nf_conntrack_timeout_fini(net); | |
dd705072 | 1591 | err_timeout: |
6ba90067 | 1592 | nf_conntrack_ecache_fini(net); |
a0891aa6 | 1593 | err_ecache: |
a992ca2a PNA |
1594 | nf_conntrack_tstamp_fini(net); |
1595 | err_tstamp: | |
a0891aa6 | 1596 | nf_conntrack_acct_fini(net); |
08f6547d | 1597 | err_acct: |
9b03f38d | 1598 | nf_conntrack_expect_fini(net); |
08f6547d | 1599 | err_expect: |
d862a662 | 1600 | nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size); |
6058fa6b | 1601 | err_hash: |
5b3501fa ED |
1602 | kmem_cache_destroy(net->ct.nf_conntrack_cachep); |
1603 | err_cache: | |
1604 | kfree(net->ct.slabname); | |
1605 | err_slabname: | |
0d55af87 AD |
1606 | free_percpu(net->ct.stat); |
1607 | err_stat: | |
08f6547d AD |
1608 | return ret; |
1609 | } | |
1610 | ||
f9dd09c7 JK |
1611 | s16 (*nf_ct_nat_offset)(const struct nf_conn *ct, |
1612 | enum ip_conntrack_dir dir, | |
1613 | u32 seq); | |
1614 | EXPORT_SYMBOL_GPL(nf_ct_nat_offset); | |
1615 | ||
08f6547d AD |
1616 | int nf_conntrack_init(struct net *net) |
1617 | { | |
1618 | int ret; | |
1619 | ||
1620 | if (net_eq(net, &init_net)) { | |
1621 | ret = nf_conntrack_init_init_net(); | |
1622 | if (ret < 0) | |
1623 | goto out_init_net; | |
1624 | } | |
15f585bd G |
1625 | ret = nf_conntrack_proto_init(net); |
1626 | if (ret < 0) | |
1627 | goto out_proto; | |
08f6547d AD |
1628 | ret = nf_conntrack_init_net(net); |
1629 | if (ret < 0) | |
1630 | goto out_net; | |
1631 | ||
1632 | if (net_eq(net, &init_net)) { | |
1633 | /* For use by REJECT target */ | |
a9b3cd7f SH |
1634 | RCU_INIT_POINTER(ip_ct_attach, nf_conntrack_attach); |
1635 | RCU_INIT_POINTER(nf_ct_destroy, destroy_conntrack); | |
f9dd09c7 JK |
1636 | |
1637 | /* Howto get NAT offsets */ | |
a9b3cd7f | 1638 | RCU_INIT_POINTER(nf_ct_nat_offset, NULL); |
08f6547d AD |
1639 | } |
1640 | return 0; | |
1641 | ||
1642 | out_net: | |
15f585bd G |
1643 | nf_conntrack_proto_fini(net); |
1644 | out_proto: | |
08f6547d AD |
1645 | if (net_eq(net, &init_net)) |
1646 | nf_conntrack_cleanup_init_net(); | |
1647 | out_init_net: | |
1648 | return ret; | |
9fb9cbb1 | 1649 | } |