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Commit | Line | Data |
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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> |
e6a7d3c0 | 47 | #include <net/netfilter/nf_nat.h> |
e17b666a | 48 | #include <net/netfilter/nf_nat_core.h> |
9fb9cbb1 | 49 | |
dc808fe2 | 50 | #define NF_CONNTRACK_VERSION "0.5.0" |
9fb9cbb1 | 51 | |
e17b666a PM |
52 | int (*nfnetlink_parse_nat_setup_hook)(struct nf_conn *ct, |
53 | enum nf_nat_manip_type manip, | |
39938324 | 54 | const struct nlattr *attr) __read_mostly; |
e6a7d3c0 PNA |
55 | EXPORT_SYMBOL_GPL(nfnetlink_parse_nat_setup_hook); |
56 | ||
f8ba1aff | 57 | DEFINE_SPINLOCK(nf_conntrack_lock); |
13b18339 | 58 | EXPORT_SYMBOL_GPL(nf_conntrack_lock); |
9fb9cbb1 | 59 | |
e2b7606c | 60 | unsigned int nf_conntrack_htable_size __read_mostly; |
13b18339 PM |
61 | EXPORT_SYMBOL_GPL(nf_conntrack_htable_size); |
62 | ||
e478075c | 63 | unsigned int nf_conntrack_max __read_mostly; |
a999e683 | 64 | EXPORT_SYMBOL_GPL(nf_conntrack_max); |
13b18339 | 65 | |
b3c5163f ED |
66 | DEFINE_PER_CPU(struct nf_conn, nf_conntrack_untracked); |
67 | EXPORT_PER_CPU_SYMBOL(nf_conntrack_untracked); | |
13b18339 | 68 | |
f682cefa | 69 | unsigned int nf_conntrack_hash_rnd __read_mostly; |
9fb9cbb1 | 70 | |
99f07e91 | 71 | static u32 hash_conntrack_raw(const struct nf_conntrack_tuple *tuple, u16 zone) |
9fb9cbb1 | 72 | { |
0794935e | 73 | unsigned int n; |
0794935e PM |
74 | |
75 | /* The direction must be ignored, so we hash everything up to the | |
76 | * destination ports (which is a multiple of 4) and treat the last | |
77 | * three bytes manually. | |
78 | */ | |
79 | n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32); | |
99f07e91 CG |
80 | return jhash2((u32 *)tuple, n, zone ^ nf_conntrack_hash_rnd ^ |
81 | (((__force __u16)tuple->dst.u.all << 16) | | |
82 | tuple->dst.protonum)); | |
83 | } | |
84 | ||
85 | static u32 __hash_bucket(u32 hash, unsigned int size) | |
86 | { | |
87 | return ((u64)hash * size) >> 32; | |
88 | } | |
89 | ||
90 | static u32 hash_bucket(u32 hash, const struct net *net) | |
91 | { | |
92 | return __hash_bucket(hash, net->ct.htable_size); | |
93 | } | |
0794935e | 94 | |
99f07e91 CG |
95 | static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple, |
96 | u16 zone, unsigned int size) | |
97 | { | |
98 | return __hash_bucket(hash_conntrack_raw(tuple, zone), size); | |
9fb9cbb1 YK |
99 | } |
100 | ||
5d0aa2cc | 101 | static inline u_int32_t hash_conntrack(const struct net *net, u16 zone, |
d696c7bd | 102 | const struct nf_conntrack_tuple *tuple) |
9fb9cbb1 | 103 | { |
99f07e91 | 104 | return __hash_conntrack(tuple, zone, net->ct.htable_size); |
9fb9cbb1 YK |
105 | } |
106 | ||
5f2b4c90 | 107 | bool |
9fb9cbb1 YK |
108 | nf_ct_get_tuple(const struct sk_buff *skb, |
109 | unsigned int nhoff, | |
110 | unsigned int dataoff, | |
111 | u_int16_t l3num, | |
112 | u_int8_t protonum, | |
113 | struct nf_conntrack_tuple *tuple, | |
114 | const struct nf_conntrack_l3proto *l3proto, | |
605dcad6 | 115 | const struct nf_conntrack_l4proto *l4proto) |
9fb9cbb1 | 116 | { |
443a70d5 | 117 | memset(tuple, 0, sizeof(*tuple)); |
9fb9cbb1 YK |
118 | |
119 | tuple->src.l3num = l3num; | |
120 | if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0) | |
5f2b4c90 | 121 | return false; |
9fb9cbb1 YK |
122 | |
123 | tuple->dst.protonum = protonum; | |
124 | tuple->dst.dir = IP_CT_DIR_ORIGINAL; | |
125 | ||
605dcad6 | 126 | return l4proto->pkt_to_tuple(skb, dataoff, tuple); |
9fb9cbb1 | 127 | } |
13b18339 | 128 | EXPORT_SYMBOL_GPL(nf_ct_get_tuple); |
9fb9cbb1 | 129 | |
5f2b4c90 JE |
130 | bool nf_ct_get_tuplepr(const struct sk_buff *skb, unsigned int nhoff, |
131 | u_int16_t l3num, struct nf_conntrack_tuple *tuple) | |
e2a3123f YK |
132 | { |
133 | struct nf_conntrack_l3proto *l3proto; | |
134 | struct nf_conntrack_l4proto *l4proto; | |
135 | unsigned int protoff; | |
136 | u_int8_t protonum; | |
137 | int ret; | |
138 | ||
139 | rcu_read_lock(); | |
140 | ||
141 | l3proto = __nf_ct_l3proto_find(l3num); | |
142 | ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum); | |
143 | if (ret != NF_ACCEPT) { | |
144 | rcu_read_unlock(); | |
5f2b4c90 | 145 | return false; |
e2a3123f YK |
146 | } |
147 | ||
148 | l4proto = __nf_ct_l4proto_find(l3num, protonum); | |
149 | ||
150 | ret = nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, tuple, | |
151 | l3proto, l4proto); | |
152 | ||
153 | rcu_read_unlock(); | |
154 | return ret; | |
155 | } | |
156 | EXPORT_SYMBOL_GPL(nf_ct_get_tuplepr); | |
157 | ||
5f2b4c90 | 158 | bool |
9fb9cbb1 YK |
159 | nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse, |
160 | const struct nf_conntrack_tuple *orig, | |
161 | const struct nf_conntrack_l3proto *l3proto, | |
605dcad6 | 162 | const struct nf_conntrack_l4proto *l4proto) |
9fb9cbb1 | 163 | { |
443a70d5 | 164 | memset(inverse, 0, sizeof(*inverse)); |
9fb9cbb1 YK |
165 | |
166 | inverse->src.l3num = orig->src.l3num; | |
167 | if (l3proto->invert_tuple(inverse, orig) == 0) | |
5f2b4c90 | 168 | return false; |
9fb9cbb1 YK |
169 | |
170 | inverse->dst.dir = !orig->dst.dir; | |
171 | ||
172 | inverse->dst.protonum = orig->dst.protonum; | |
605dcad6 | 173 | return l4proto->invert_tuple(inverse, orig); |
9fb9cbb1 | 174 | } |
13b18339 | 175 | EXPORT_SYMBOL_GPL(nf_ct_invert_tuple); |
9fb9cbb1 | 176 | |
9fb9cbb1 YK |
177 | static void |
178 | clean_from_lists(struct nf_conn *ct) | |
179 | { | |
0d53778e | 180 | pr_debug("clean_from_lists(%p)\n", ct); |
ea781f19 ED |
181 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); |
182 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode); | |
9fb9cbb1 YK |
183 | |
184 | /* Destroy all pending expectations */ | |
c1d10adb | 185 | nf_ct_remove_expectations(ct); |
9fb9cbb1 YK |
186 | } |
187 | ||
188 | static void | |
189 | destroy_conntrack(struct nf_conntrack *nfct) | |
190 | { | |
191 | struct nf_conn *ct = (struct nf_conn *)nfct; | |
0d55af87 | 192 | struct net *net = nf_ct_net(ct); |
605dcad6 | 193 | struct nf_conntrack_l4proto *l4proto; |
9fb9cbb1 | 194 | |
0d53778e | 195 | pr_debug("destroy_conntrack(%p)\n", ct); |
9fb9cbb1 YK |
196 | NF_CT_ASSERT(atomic_read(&nfct->use) == 0); |
197 | NF_CT_ASSERT(!timer_pending(&ct->timeout)); | |
198 | ||
9fb9cbb1 YK |
199 | /* To make sure we don't get any weird locking issues here: |
200 | * destroy_conntrack() MUST NOT be called with a write lock | |
201 | * to nf_conntrack_lock!!! -HW */ | |
923f4902 | 202 | rcu_read_lock(); |
5e8fbe2a | 203 | l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct)); |
605dcad6 MJ |
204 | if (l4proto && l4proto->destroy) |
205 | l4proto->destroy(ct); | |
9fb9cbb1 | 206 | |
982d9a9c | 207 | rcu_read_unlock(); |
9fb9cbb1 | 208 | |
f8ba1aff | 209 | spin_lock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
210 | /* Expectations will have been removed in clean_from_lists, |
211 | * except TFTP can create an expectation on the first packet, | |
212 | * before connection is in the list, so we need to clean here, | |
213 | * too. */ | |
c1d10adb | 214 | nf_ct_remove_expectations(ct); |
9fb9cbb1 YK |
215 | |
216 | /* We overload first tuple to link into unconfirmed list. */ | |
217 | if (!nf_ct_is_confirmed(ct)) { | |
ea781f19 ED |
218 | BUG_ON(hlist_nulls_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode)); |
219 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); | |
9fb9cbb1 YK |
220 | } |
221 | ||
0d55af87 | 222 | NF_CT_STAT_INC(net, delete); |
f8ba1aff | 223 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
224 | |
225 | if (ct->master) | |
226 | nf_ct_put(ct->master); | |
227 | ||
0d53778e | 228 | pr_debug("destroy_conntrack: returning ct=%p to slab\n", ct); |
9fb9cbb1 YK |
229 | nf_conntrack_free(ct); |
230 | } | |
231 | ||
dd7669a9 | 232 | void nf_ct_delete_from_lists(struct nf_conn *ct) |
9fb9cbb1 | 233 | { |
0d55af87 | 234 | struct net *net = nf_ct_net(ct); |
9fb9cbb1 | 235 | |
9858a3ae | 236 | nf_ct_helper_destroy(ct); |
f8ba1aff | 237 | spin_lock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
238 | /* Inside lock so preempt is disabled on module removal path. |
239 | * Otherwise we can get spurious warnings. */ | |
0d55af87 | 240 | NF_CT_STAT_INC(net, delete_list); |
9fb9cbb1 | 241 | clean_from_lists(ct); |
f8ba1aff | 242 | spin_unlock_bh(&nf_conntrack_lock); |
dd7669a9 PNA |
243 | } |
244 | EXPORT_SYMBOL_GPL(nf_ct_delete_from_lists); | |
245 | ||
246 | static void death_by_event(unsigned long ul_conntrack) | |
247 | { | |
248 | struct nf_conn *ct = (void *)ul_conntrack; | |
249 | struct net *net = nf_ct_net(ct); | |
250 | ||
251 | if (nf_conntrack_event(IPCT_DESTROY, ct) < 0) { | |
252 | /* bad luck, let's retry again */ | |
253 | ct->timeout.expires = jiffies + | |
254 | (random32() % net->ct.sysctl_events_retry_timeout); | |
255 | add_timer(&ct->timeout); | |
256 | return; | |
257 | } | |
258 | /* we've got the event delivered, now it's dying */ | |
259 | set_bit(IPS_DYING_BIT, &ct->status); | |
260 | spin_lock(&nf_conntrack_lock); | |
261 | hlist_nulls_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); | |
262 | spin_unlock(&nf_conntrack_lock); | |
263 | nf_ct_put(ct); | |
264 | } | |
265 | ||
266 | void nf_ct_insert_dying_list(struct nf_conn *ct) | |
267 | { | |
268 | struct net *net = nf_ct_net(ct); | |
269 | ||
270 | /* add this conntrack to the dying list */ | |
271 | spin_lock_bh(&nf_conntrack_lock); | |
272 | hlist_nulls_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, | |
273 | &net->ct.dying); | |
274 | spin_unlock_bh(&nf_conntrack_lock); | |
275 | /* set a new timer to retry event delivery */ | |
276 | setup_timer(&ct->timeout, death_by_event, (unsigned long)ct); | |
277 | ct->timeout.expires = jiffies + | |
278 | (random32() % net->ct.sysctl_events_retry_timeout); | |
279 | add_timer(&ct->timeout); | |
280 | } | |
281 | EXPORT_SYMBOL_GPL(nf_ct_insert_dying_list); | |
282 | ||
283 | static void death_by_timeout(unsigned long ul_conntrack) | |
284 | { | |
285 | struct nf_conn *ct = (void *)ul_conntrack; | |
a992ca2a PNA |
286 | struct nf_conn_tstamp *tstamp; |
287 | ||
288 | tstamp = nf_conn_tstamp_find(ct); | |
289 | if (tstamp && tstamp->stop == 0) | |
290 | tstamp->stop = ktime_to_ns(ktime_get_real()); | |
dd7669a9 PNA |
291 | |
292 | if (!test_bit(IPS_DYING_BIT, &ct->status) && | |
293 | unlikely(nf_conntrack_event(IPCT_DESTROY, ct) < 0)) { | |
294 | /* destroy event was not delivered */ | |
295 | nf_ct_delete_from_lists(ct); | |
296 | nf_ct_insert_dying_list(ct); | |
297 | return; | |
298 | } | |
299 | set_bit(IPS_DYING_BIT, &ct->status); | |
300 | nf_ct_delete_from_lists(ct); | |
9fb9cbb1 YK |
301 | nf_ct_put(ct); |
302 | } | |
303 | ||
ea781f19 ED |
304 | /* |
305 | * Warning : | |
306 | * - Caller must take a reference on returned object | |
307 | * and recheck nf_ct_tuple_equal(tuple, &h->tuple) | |
308 | * OR | |
309 | * - Caller must lock nf_conntrack_lock before calling this function | |
310 | */ | |
99f07e91 CG |
311 | static struct nf_conntrack_tuple_hash * |
312 | ____nf_conntrack_find(struct net *net, u16 zone, | |
313 | const struct nf_conntrack_tuple *tuple, u32 hash) | |
9fb9cbb1 YK |
314 | { |
315 | struct nf_conntrack_tuple_hash *h; | |
ea781f19 | 316 | struct hlist_nulls_node *n; |
99f07e91 | 317 | unsigned int bucket = hash_bucket(hash, net); |
9fb9cbb1 | 318 | |
4e29e9ec PM |
319 | /* Disable BHs the entire time since we normally need to disable them |
320 | * at least once for the stats anyway. | |
321 | */ | |
322 | local_bh_disable(); | |
ea781f19 | 323 | begin: |
99f07e91 | 324 | hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[bucket], hnnode) { |
5d0aa2cc PM |
325 | if (nf_ct_tuple_equal(tuple, &h->tuple) && |
326 | nf_ct_zone(nf_ct_tuplehash_to_ctrack(h)) == zone) { | |
0d55af87 | 327 | NF_CT_STAT_INC(net, found); |
4e29e9ec | 328 | local_bh_enable(); |
9fb9cbb1 YK |
329 | return h; |
330 | } | |
0d55af87 | 331 | NF_CT_STAT_INC(net, searched); |
9fb9cbb1 | 332 | } |
ea781f19 ED |
333 | /* |
334 | * if the nulls value we got at the end of this lookup is | |
335 | * not the expected one, we must restart lookup. | |
336 | * We probably met an item that was moved to another chain. | |
337 | */ | |
99f07e91 | 338 | if (get_nulls_value(n) != bucket) { |
af740b2c | 339 | NF_CT_STAT_INC(net, search_restart); |
ea781f19 | 340 | goto begin; |
af740b2c | 341 | } |
4e29e9ec | 342 | local_bh_enable(); |
9fb9cbb1 YK |
343 | |
344 | return NULL; | |
345 | } | |
99f07e91 CG |
346 | |
347 | struct nf_conntrack_tuple_hash * | |
348 | __nf_conntrack_find(struct net *net, u16 zone, | |
349 | const struct nf_conntrack_tuple *tuple) | |
350 | { | |
351 | return ____nf_conntrack_find(net, zone, tuple, | |
352 | hash_conntrack_raw(tuple, zone)); | |
353 | } | |
13b18339 | 354 | EXPORT_SYMBOL_GPL(__nf_conntrack_find); |
9fb9cbb1 YK |
355 | |
356 | /* Find a connection corresponding to a tuple. */ | |
99f07e91 CG |
357 | static struct nf_conntrack_tuple_hash * |
358 | __nf_conntrack_find_get(struct net *net, u16 zone, | |
359 | const struct nf_conntrack_tuple *tuple, u32 hash) | |
9fb9cbb1 YK |
360 | { |
361 | struct nf_conntrack_tuple_hash *h; | |
76507f69 | 362 | struct nf_conn *ct; |
9fb9cbb1 | 363 | |
76507f69 | 364 | rcu_read_lock(); |
ea781f19 | 365 | begin: |
99f07e91 | 366 | h = ____nf_conntrack_find(net, zone, tuple, hash); |
76507f69 PM |
367 | if (h) { |
368 | ct = nf_ct_tuplehash_to_ctrack(h); | |
8d8890b7 PM |
369 | if (unlikely(nf_ct_is_dying(ct) || |
370 | !atomic_inc_not_zero(&ct->ct_general.use))) | |
76507f69 | 371 | h = NULL; |
ea781f19 | 372 | else { |
5d0aa2cc PM |
373 | if (unlikely(!nf_ct_tuple_equal(tuple, &h->tuple) || |
374 | nf_ct_zone(ct) != zone)) { | |
ea781f19 ED |
375 | nf_ct_put(ct); |
376 | goto begin; | |
377 | } | |
378 | } | |
76507f69 PM |
379 | } |
380 | rcu_read_unlock(); | |
9fb9cbb1 YK |
381 | |
382 | return h; | |
383 | } | |
99f07e91 CG |
384 | |
385 | struct nf_conntrack_tuple_hash * | |
386 | nf_conntrack_find_get(struct net *net, u16 zone, | |
387 | const struct nf_conntrack_tuple *tuple) | |
388 | { | |
389 | return __nf_conntrack_find_get(net, zone, tuple, | |
390 | hash_conntrack_raw(tuple, zone)); | |
391 | } | |
13b18339 | 392 | EXPORT_SYMBOL_GPL(nf_conntrack_find_get); |
9fb9cbb1 | 393 | |
c1d10adb PNA |
394 | static void __nf_conntrack_hash_insert(struct nf_conn *ct, |
395 | unsigned int hash, | |
601e68e1 | 396 | unsigned int repl_hash) |
c1d10adb | 397 | { |
400dad39 AD |
398 | struct net *net = nf_ct_net(ct); |
399 | ||
ea781f19 | 400 | hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, |
400dad39 | 401 | &net->ct.hash[hash]); |
ea781f19 | 402 | hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode, |
400dad39 | 403 | &net->ct.hash[repl_hash]); |
c1d10adb PNA |
404 | } |
405 | ||
406 | void nf_conntrack_hash_insert(struct nf_conn *ct) | |
407 | { | |
d696c7bd | 408 | struct net *net = nf_ct_net(ct); |
c1d10adb | 409 | unsigned int hash, repl_hash; |
5d0aa2cc | 410 | u16 zone; |
c1d10adb | 411 | |
5d0aa2cc PM |
412 | zone = nf_ct_zone(ct); |
413 | hash = hash_conntrack(net, zone, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); | |
414 | repl_hash = hash_conntrack(net, zone, &ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
c1d10adb | 415 | |
c1d10adb | 416 | __nf_conntrack_hash_insert(ct, hash, repl_hash); |
c1d10adb | 417 | } |
13b18339 | 418 | EXPORT_SYMBOL_GPL(nf_conntrack_hash_insert); |
c1d10adb | 419 | |
9fb9cbb1 YK |
420 | /* Confirm a connection given skb; places it in hash table */ |
421 | int | |
3db05fea | 422 | __nf_conntrack_confirm(struct sk_buff *skb) |
9fb9cbb1 YK |
423 | { |
424 | unsigned int hash, repl_hash; | |
df0933dc | 425 | struct nf_conntrack_tuple_hash *h; |
9fb9cbb1 | 426 | struct nf_conn *ct; |
df0933dc | 427 | struct nf_conn_help *help; |
a992ca2a | 428 | struct nf_conn_tstamp *tstamp; |
ea781f19 | 429 | struct hlist_nulls_node *n; |
9fb9cbb1 | 430 | enum ip_conntrack_info ctinfo; |
400dad39 | 431 | struct net *net; |
5d0aa2cc | 432 | u16 zone; |
9fb9cbb1 | 433 | |
3db05fea | 434 | ct = nf_ct_get(skb, &ctinfo); |
400dad39 | 435 | net = nf_ct_net(ct); |
9fb9cbb1 YK |
436 | |
437 | /* ipt_REJECT uses nf_conntrack_attach to attach related | |
438 | ICMP/TCP RST packets in other direction. Actual packet | |
439 | which created connection will be IP_CT_NEW or for an | |
440 | expected connection, IP_CT_RELATED. */ | |
441 | if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) | |
442 | return NF_ACCEPT; | |
443 | ||
5d0aa2cc | 444 | zone = nf_ct_zone(ct); |
99f07e91 CG |
445 | /* reuse the hash saved before */ |
446 | hash = *(unsigned long *)&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev; | |
447 | hash = hash_bucket(hash, net); | |
448 | repl_hash = hash_conntrack(net, zone, | |
449 | &ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
9fb9cbb1 YK |
450 | |
451 | /* We're not in hash table, and we refuse to set up related | |
452 | connections for unconfirmed conns. But packet copies and | |
453 | REJECT will give spurious warnings here. */ | |
454 | /* NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 1); */ | |
455 | ||
25985edc | 456 | /* No external references means no one else could have |
9fb9cbb1 YK |
457 | confirmed us. */ |
458 | NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); | |
0d53778e | 459 | pr_debug("Confirming conntrack %p\n", ct); |
9fb9cbb1 | 460 | |
f8ba1aff | 461 | spin_lock_bh(&nf_conntrack_lock); |
9fb9cbb1 | 462 | |
fc350777 JM |
463 | /* We have to check the DYING flag inside the lock to prevent |
464 | a race against nf_ct_get_next_corpse() possibly called from | |
465 | user context, else we insert an already 'dead' hash, blocking | |
466 | further use of that particular connection -JM */ | |
467 | ||
468 | if (unlikely(nf_ct_is_dying(ct))) { | |
469 | spin_unlock_bh(&nf_conntrack_lock); | |
470 | return NF_ACCEPT; | |
471 | } | |
472 | ||
9fb9cbb1 YK |
473 | /* See if there's one in the list already, including reverse: |
474 | NAT could have grabbed it without realizing, since we're | |
475 | not in the hash. If there is, we lost race. */ | |
ea781f19 | 476 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[hash], hnnode) |
df0933dc | 477 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, |
5d0aa2cc PM |
478 | &h->tuple) && |
479 | zone == nf_ct_zone(nf_ct_tuplehash_to_ctrack(h))) | |
df0933dc | 480 | goto out; |
ea781f19 | 481 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[repl_hash], hnnode) |
df0933dc | 482 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple, |
5d0aa2cc PM |
483 | &h->tuple) && |
484 | zone == nf_ct_zone(nf_ct_tuplehash_to_ctrack(h))) | |
df0933dc | 485 | goto out; |
9fb9cbb1 | 486 | |
df0933dc | 487 | /* Remove from unconfirmed list */ |
ea781f19 | 488 | hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); |
df0933dc | 489 | |
df0933dc PM |
490 | /* Timer relative to confirmation time, not original |
491 | setting time, otherwise we'd get timer wrap in | |
492 | weird delay cases. */ | |
493 | ct->timeout.expires += jiffies; | |
494 | add_timer(&ct->timeout); | |
495 | atomic_inc(&ct->ct_general.use); | |
45eec341 | 496 | ct->status |= IPS_CONFIRMED; |
5c8ec910 | 497 | |
a992ca2a PNA |
498 | /* set conntrack timestamp, if enabled. */ |
499 | tstamp = nf_conn_tstamp_find(ct); | |
500 | if (tstamp) { | |
501 | if (skb->tstamp.tv64 == 0) | |
502 | __net_timestamp((struct sk_buff *)skb); | |
503 | ||
504 | tstamp->start = ktime_to_ns(skb->tstamp); | |
505 | } | |
5c8ec910 PM |
506 | /* Since the lookup is lockless, hash insertion must be done after |
507 | * starting the timer and setting the CONFIRMED bit. The RCU barriers | |
508 | * guarantee that no other CPU can find the conntrack before the above | |
509 | * stores are visible. | |
510 | */ | |
511 | __nf_conntrack_hash_insert(ct, hash, repl_hash); | |
0d55af87 | 512 | NF_CT_STAT_INC(net, insert); |
f8ba1aff | 513 | spin_unlock_bh(&nf_conntrack_lock); |
5c8ec910 | 514 | |
df0933dc PM |
515 | help = nfct_help(ct); |
516 | if (help && help->helper) | |
a71996fc | 517 | nf_conntrack_event_cache(IPCT_HELPER, ct); |
17e6e4ea | 518 | |
df0933dc | 519 | nf_conntrack_event_cache(master_ct(ct) ? |
a71996fc | 520 | IPCT_RELATED : IPCT_NEW, ct); |
df0933dc | 521 | return NF_ACCEPT; |
9fb9cbb1 | 522 | |
df0933dc | 523 | out: |
0d55af87 | 524 | NF_CT_STAT_INC(net, insert_failed); |
f8ba1aff | 525 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
526 | return NF_DROP; |
527 | } | |
13b18339 | 528 | EXPORT_SYMBOL_GPL(__nf_conntrack_confirm); |
9fb9cbb1 YK |
529 | |
530 | /* Returns true if a connection correspondings to the tuple (required | |
531 | for NAT). */ | |
532 | int | |
533 | nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple, | |
534 | const struct nf_conn *ignored_conntrack) | |
535 | { | |
400dad39 | 536 | struct net *net = nf_ct_net(ignored_conntrack); |
9fb9cbb1 | 537 | struct nf_conntrack_tuple_hash *h; |
ea781f19 | 538 | struct hlist_nulls_node *n; |
5d0aa2cc PM |
539 | struct nf_conn *ct; |
540 | u16 zone = nf_ct_zone(ignored_conntrack); | |
541 | unsigned int hash = hash_conntrack(net, zone, tuple); | |
9fb9cbb1 | 542 | |
4e29e9ec PM |
543 | /* Disable BHs the entire time since we need to disable them at |
544 | * least once for the stats anyway. | |
545 | */ | |
546 | rcu_read_lock_bh(); | |
ea781f19 | 547 | hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], hnnode) { |
5d0aa2cc PM |
548 | ct = nf_ct_tuplehash_to_ctrack(h); |
549 | if (ct != ignored_conntrack && | |
550 | nf_ct_tuple_equal(tuple, &h->tuple) && | |
551 | nf_ct_zone(ct) == zone) { | |
0d55af87 | 552 | NF_CT_STAT_INC(net, found); |
4e29e9ec | 553 | rcu_read_unlock_bh(); |
ba419aff PM |
554 | return 1; |
555 | } | |
0d55af87 | 556 | NF_CT_STAT_INC(net, searched); |
ba419aff | 557 | } |
4e29e9ec | 558 | rcu_read_unlock_bh(); |
9fb9cbb1 | 559 | |
ba419aff | 560 | return 0; |
9fb9cbb1 | 561 | } |
13b18339 | 562 | EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken); |
9fb9cbb1 | 563 | |
7ae7730f PM |
564 | #define NF_CT_EVICTION_RANGE 8 |
565 | ||
9fb9cbb1 YK |
566 | /* There's a small race here where we may free a just-assured |
567 | connection. Too bad: we're in trouble anyway. */ | |
400dad39 | 568 | static noinline int early_drop(struct net *net, unsigned int hash) |
9fb9cbb1 | 569 | { |
f205c5e0 | 570 | /* Use oldest entry, which is roughly LRU */ |
9fb9cbb1 | 571 | struct nf_conntrack_tuple_hash *h; |
df0933dc | 572 | struct nf_conn *ct = NULL, *tmp; |
ea781f19 | 573 | struct hlist_nulls_node *n; |
7ae7730f | 574 | unsigned int i, cnt = 0; |
9fb9cbb1 YK |
575 | int dropped = 0; |
576 | ||
76507f69 | 577 | rcu_read_lock(); |
d696c7bd | 578 | for (i = 0; i < net->ct.htable_size; i++) { |
ea781f19 ED |
579 | hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], |
580 | hnnode) { | |
7ae7730f PM |
581 | tmp = nf_ct_tuplehash_to_ctrack(h); |
582 | if (!test_bit(IPS_ASSURED_BIT, &tmp->status)) | |
583 | ct = tmp; | |
584 | cnt++; | |
585 | } | |
76507f69 | 586 | |
5ae27aa2 CG |
587 | if (ct != NULL) { |
588 | if (likely(!nf_ct_is_dying(ct) && | |
589 | atomic_inc_not_zero(&ct->ct_general.use))) | |
590 | break; | |
591 | else | |
592 | ct = NULL; | |
593 | } | |
594 | ||
595 | if (cnt >= NF_CT_EVICTION_RANGE) | |
7ae7730f | 596 | break; |
5ae27aa2 | 597 | |
d696c7bd | 598 | hash = (hash + 1) % net->ct.htable_size; |
9fb9cbb1 | 599 | } |
76507f69 | 600 | rcu_read_unlock(); |
9fb9cbb1 YK |
601 | |
602 | if (!ct) | |
603 | return dropped; | |
604 | ||
605 | if (del_timer(&ct->timeout)) { | |
606 | death_by_timeout((unsigned long)ct); | |
607 | dropped = 1; | |
0d55af87 | 608 | NF_CT_STAT_INC_ATOMIC(net, early_drop); |
9fb9cbb1 YK |
609 | } |
610 | nf_ct_put(ct); | |
611 | return dropped; | |
612 | } | |
613 | ||
f682cefa CG |
614 | void init_nf_conntrack_hash_rnd(void) |
615 | { | |
616 | unsigned int rand; | |
617 | ||
618 | /* | |
619 | * Why not initialize nf_conntrack_rnd in a "init()" function ? | |
620 | * Because there isn't enough entropy when system initializing, | |
621 | * and we initialize it as late as possible. | |
622 | */ | |
623 | do { | |
624 | get_random_bytes(&rand, sizeof(rand)); | |
625 | } while (!rand); | |
626 | cmpxchg(&nf_conntrack_hash_rnd, 0, rand); | |
627 | } | |
628 | ||
99f07e91 CG |
629 | static struct nf_conn * |
630 | __nf_conntrack_alloc(struct net *net, u16 zone, | |
631 | const struct nf_conntrack_tuple *orig, | |
632 | const struct nf_conntrack_tuple *repl, | |
633 | gfp_t gfp, u32 hash) | |
9fb9cbb1 | 634 | { |
cd7fcbf1 | 635 | struct nf_conn *ct; |
9fb9cbb1 | 636 | |
b2390969 | 637 | if (unlikely(!nf_conntrack_hash_rnd)) { |
f682cefa | 638 | init_nf_conntrack_hash_rnd(); |
99f07e91 CG |
639 | /* recompute the hash as nf_conntrack_hash_rnd is initialized */ |
640 | hash = hash_conntrack_raw(orig, zone); | |
9fb9cbb1 YK |
641 | } |
642 | ||
5251e2d2 | 643 | /* We don't want any race condition at early drop stage */ |
49ac8713 | 644 | atomic_inc(&net->ct.count); |
5251e2d2 | 645 | |
76eb9460 | 646 | if (nf_conntrack_max && |
49ac8713 | 647 | unlikely(atomic_read(&net->ct.count) > nf_conntrack_max)) { |
99f07e91 | 648 | if (!early_drop(net, hash_bucket(hash, net))) { |
49ac8713 | 649 | atomic_dec(&net->ct.count); |
9fb9cbb1 YK |
650 | if (net_ratelimit()) |
651 | printk(KERN_WARNING | |
652 | "nf_conntrack: table full, dropping" | |
653 | " packet.\n"); | |
654 | return ERR_PTR(-ENOMEM); | |
655 | } | |
656 | } | |
657 | ||
941297f4 ED |
658 | /* |
659 | * Do not use kmem_cache_zalloc(), as this cache uses | |
660 | * SLAB_DESTROY_BY_RCU. | |
661 | */ | |
5b3501fa | 662 | ct = kmem_cache_alloc(net->ct.nf_conntrack_cachep, gfp); |
c88130bc | 663 | if (ct == NULL) { |
0d53778e | 664 | pr_debug("nf_conntrack_alloc: Can't alloc conntrack.\n"); |
49ac8713 | 665 | atomic_dec(&net->ct.count); |
dacd2a1a | 666 | return ERR_PTR(-ENOMEM); |
9fb9cbb1 | 667 | } |
941297f4 ED |
668 | /* |
669 | * Let ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode.next | |
670 | * and ct->tuplehash[IP_CT_DIR_REPLY].hnnode.next unchanged. | |
671 | */ | |
672 | memset(&ct->tuplehash[IP_CT_DIR_MAX], 0, | |
e5fc9e7a CG |
673 | offsetof(struct nf_conn, proto) - |
674 | offsetof(struct nf_conn, tuplehash[IP_CT_DIR_MAX])); | |
440f0d58 | 675 | spin_lock_init(&ct->lock); |
c88130bc | 676 | ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig; |
941297f4 | 677 | ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode.pprev = NULL; |
c88130bc | 678 | ct->tuplehash[IP_CT_DIR_REPLY].tuple = *repl; |
99f07e91 CG |
679 | /* save hash for reusing when confirming */ |
680 | *(unsigned long *)(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev) = hash; | |
9fb9cbb1 | 681 | /* Don't set timer yet: wait for confirmation */ |
c88130bc | 682 | setup_timer(&ct->timeout, death_by_timeout, (unsigned long)ct); |
c2d9ba9b | 683 | write_pnet(&ct->ct_net, net); |
5d0aa2cc PM |
684 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
685 | if (zone) { | |
686 | struct nf_conntrack_zone *nf_ct_zone; | |
687 | ||
688 | nf_ct_zone = nf_ct_ext_add(ct, NF_CT_EXT_ZONE, GFP_ATOMIC); | |
689 | if (!nf_ct_zone) | |
690 | goto out_free; | |
691 | nf_ct_zone->id = zone; | |
692 | } | |
693 | #endif | |
941297f4 ED |
694 | /* |
695 | * changes to lookup keys must be done before setting refcnt to 1 | |
696 | */ | |
697 | smp_wmb(); | |
698 | atomic_set(&ct->ct_general.use, 1); | |
c88130bc | 699 | return ct; |
5d0aa2cc PM |
700 | |
701 | #ifdef CONFIG_NF_CONNTRACK_ZONES | |
702 | out_free: | |
703 | kmem_cache_free(net->ct.nf_conntrack_cachep, ct); | |
704 | return ERR_PTR(-ENOMEM); | |
705 | #endif | |
9fb9cbb1 | 706 | } |
99f07e91 CG |
707 | |
708 | struct nf_conn *nf_conntrack_alloc(struct net *net, u16 zone, | |
709 | const struct nf_conntrack_tuple *orig, | |
710 | const struct nf_conntrack_tuple *repl, | |
711 | gfp_t gfp) | |
712 | { | |
713 | return __nf_conntrack_alloc(net, zone, orig, repl, gfp, 0); | |
714 | } | |
13b18339 | 715 | EXPORT_SYMBOL_GPL(nf_conntrack_alloc); |
9fb9cbb1 | 716 | |
c88130bc | 717 | void nf_conntrack_free(struct nf_conn *ct) |
76507f69 | 718 | { |
1d45209d ED |
719 | struct net *net = nf_ct_net(ct); |
720 | ||
ceeff754 | 721 | nf_ct_ext_destroy(ct); |
1d45209d | 722 | atomic_dec(&net->ct.count); |
ea781f19 | 723 | nf_ct_ext_free(ct); |
5b3501fa | 724 | kmem_cache_free(net->ct.nf_conntrack_cachep, ct); |
76507f69 | 725 | } |
13b18339 | 726 | EXPORT_SYMBOL_GPL(nf_conntrack_free); |
9fb9cbb1 YK |
727 | |
728 | /* Allocate a new conntrack: we return -ENOMEM if classification | |
729 | failed due to stress. Otherwise it really is unclassifiable. */ | |
730 | static struct nf_conntrack_tuple_hash * | |
b2a15a60 | 731 | init_conntrack(struct net *net, struct nf_conn *tmpl, |
5a1fb391 | 732 | const struct nf_conntrack_tuple *tuple, |
9fb9cbb1 | 733 | struct nf_conntrack_l3proto *l3proto, |
605dcad6 | 734 | struct nf_conntrack_l4proto *l4proto, |
9fb9cbb1 | 735 | struct sk_buff *skb, |
99f07e91 | 736 | unsigned int dataoff, u32 hash) |
9fb9cbb1 | 737 | { |
c88130bc | 738 | struct nf_conn *ct; |
3c158f7f | 739 | struct nf_conn_help *help; |
9fb9cbb1 | 740 | struct nf_conntrack_tuple repl_tuple; |
b2a15a60 | 741 | struct nf_conntrack_ecache *ecache; |
9fb9cbb1 | 742 | struct nf_conntrack_expect *exp; |
5d0aa2cc | 743 | u16 zone = tmpl ? nf_ct_zone(tmpl) : NF_CT_DEFAULT_ZONE; |
9fb9cbb1 | 744 | |
605dcad6 | 745 | if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) { |
0d53778e | 746 | pr_debug("Can't invert tuple.\n"); |
9fb9cbb1 YK |
747 | return NULL; |
748 | } | |
749 | ||
99f07e91 CG |
750 | ct = __nf_conntrack_alloc(net, zone, tuple, &repl_tuple, GFP_ATOMIC, |
751 | hash); | |
cd7fcbf1 | 752 | if (IS_ERR(ct)) { |
0d53778e | 753 | pr_debug("Can't allocate conntrack.\n"); |
c88130bc | 754 | return (struct nf_conntrack_tuple_hash *)ct; |
9fb9cbb1 YK |
755 | } |
756 | ||
c88130bc PM |
757 | if (!l4proto->new(ct, skb, dataoff)) { |
758 | nf_conntrack_free(ct); | |
0d53778e | 759 | pr_debug("init conntrack: can't track with proto module\n"); |
9fb9cbb1 YK |
760 | return NULL; |
761 | } | |
762 | ||
58401572 | 763 | nf_ct_acct_ext_add(ct, GFP_ATOMIC); |
a992ca2a | 764 | nf_ct_tstamp_ext_add(ct, GFP_ATOMIC); |
b2a15a60 PM |
765 | |
766 | ecache = tmpl ? nf_ct_ecache_find(tmpl) : NULL; | |
767 | nf_ct_ecache_ext_add(ct, ecache ? ecache->ctmask : 0, | |
768 | ecache ? ecache->expmask : 0, | |
769 | GFP_ATOMIC); | |
58401572 | 770 | |
f8ba1aff | 771 | spin_lock_bh(&nf_conntrack_lock); |
5d0aa2cc | 772 | exp = nf_ct_find_expectation(net, zone, tuple); |
9fb9cbb1 | 773 | if (exp) { |
0d53778e | 774 | pr_debug("conntrack: expectation arrives ct=%p exp=%p\n", |
c88130bc | 775 | ct, exp); |
9fb9cbb1 | 776 | /* Welcome, Mr. Bond. We've been expecting you... */ |
c88130bc PM |
777 | __set_bit(IPS_EXPECTED_BIT, &ct->status); |
778 | ct->master = exp->master; | |
ceceae1b | 779 | if (exp->helper) { |
c88130bc | 780 | help = nf_ct_helper_ext_add(ct, GFP_ATOMIC); |
ceceae1b YK |
781 | if (help) |
782 | rcu_assign_pointer(help->helper, exp->helper); | |
ceceae1b YK |
783 | } |
784 | ||
9fb9cbb1 | 785 | #ifdef CONFIG_NF_CONNTRACK_MARK |
c88130bc | 786 | ct->mark = exp->master->mark; |
7c9728c3 JM |
787 | #endif |
788 | #ifdef CONFIG_NF_CONNTRACK_SECMARK | |
c88130bc | 789 | ct->secmark = exp->master->secmark; |
9fb9cbb1 | 790 | #endif |
c88130bc | 791 | nf_conntrack_get(&ct->master->ct_general); |
0d55af87 | 792 | NF_CT_STAT_INC(net, expect_new); |
22e7410b | 793 | } else { |
b2a15a60 | 794 | __nf_ct_try_assign_helper(ct, tmpl, GFP_ATOMIC); |
0d55af87 | 795 | NF_CT_STAT_INC(net, new); |
22e7410b | 796 | } |
9fb9cbb1 YK |
797 | |
798 | /* Overload tuple linked list to put us in unconfirmed list. */ | |
ea781f19 | 799 | hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, |
63c9a262 | 800 | &net->ct.unconfirmed); |
9fb9cbb1 | 801 | |
f8ba1aff | 802 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 YK |
803 | |
804 | if (exp) { | |
805 | if (exp->expectfn) | |
c88130bc | 806 | exp->expectfn(ct, exp); |
6823645d | 807 | nf_ct_expect_put(exp); |
9fb9cbb1 YK |
808 | } |
809 | ||
c88130bc | 810 | return &ct->tuplehash[IP_CT_DIR_ORIGINAL]; |
9fb9cbb1 YK |
811 | } |
812 | ||
813 | /* On success, returns conntrack ptr, sets skb->nfct and ctinfo */ | |
814 | static inline struct nf_conn * | |
b2a15a60 | 815 | resolve_normal_ct(struct net *net, struct nf_conn *tmpl, |
a702a65f | 816 | struct sk_buff *skb, |
9fb9cbb1 YK |
817 | unsigned int dataoff, |
818 | u_int16_t l3num, | |
819 | u_int8_t protonum, | |
820 | struct nf_conntrack_l3proto *l3proto, | |
605dcad6 | 821 | struct nf_conntrack_l4proto *l4proto, |
9fb9cbb1 YK |
822 | int *set_reply, |
823 | enum ip_conntrack_info *ctinfo) | |
824 | { | |
825 | struct nf_conntrack_tuple tuple; | |
826 | struct nf_conntrack_tuple_hash *h; | |
827 | struct nf_conn *ct; | |
5d0aa2cc | 828 | u16 zone = tmpl ? nf_ct_zone(tmpl) : NF_CT_DEFAULT_ZONE; |
99f07e91 | 829 | u32 hash; |
9fb9cbb1 | 830 | |
bbe735e4 | 831 | if (!nf_ct_get_tuple(skb, skb_network_offset(skb), |
9fb9cbb1 | 832 | dataoff, l3num, protonum, &tuple, l3proto, |
605dcad6 | 833 | l4proto)) { |
0d53778e | 834 | pr_debug("resolve_normal_ct: Can't get tuple\n"); |
9fb9cbb1 YK |
835 | return NULL; |
836 | } | |
837 | ||
838 | /* look for tuple match */ | |
99f07e91 CG |
839 | hash = hash_conntrack_raw(&tuple, zone); |
840 | h = __nf_conntrack_find_get(net, zone, &tuple, hash); | |
9fb9cbb1 | 841 | if (!h) { |
b2a15a60 | 842 | h = init_conntrack(net, tmpl, &tuple, l3proto, l4proto, |
99f07e91 | 843 | skb, dataoff, hash); |
9fb9cbb1 YK |
844 | if (!h) |
845 | return NULL; | |
846 | if (IS_ERR(h)) | |
847 | return (void *)h; | |
848 | } | |
849 | ct = nf_ct_tuplehash_to_ctrack(h); | |
850 | ||
851 | /* It exists; we have (non-exclusive) reference. */ | |
852 | if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) { | |
fb048833 | 853 | *ctinfo = IP_CT_ESTABLISHED_REPLY; |
9fb9cbb1 YK |
854 | /* Please set reply bit if this packet OK */ |
855 | *set_reply = 1; | |
856 | } else { | |
857 | /* Once we've had two way comms, always ESTABLISHED. */ | |
858 | if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { | |
0d53778e | 859 | pr_debug("nf_conntrack_in: normal packet for %p\n", ct); |
9fb9cbb1 YK |
860 | *ctinfo = IP_CT_ESTABLISHED; |
861 | } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) { | |
0d53778e PM |
862 | pr_debug("nf_conntrack_in: related packet for %p\n", |
863 | ct); | |
9fb9cbb1 YK |
864 | *ctinfo = IP_CT_RELATED; |
865 | } else { | |
0d53778e | 866 | pr_debug("nf_conntrack_in: new packet for %p\n", ct); |
9fb9cbb1 YK |
867 | *ctinfo = IP_CT_NEW; |
868 | } | |
869 | *set_reply = 0; | |
870 | } | |
871 | skb->nfct = &ct->ct_general; | |
872 | skb->nfctinfo = *ctinfo; | |
873 | return ct; | |
874 | } | |
875 | ||
876 | unsigned int | |
a702a65f AD |
877 | nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum, |
878 | struct sk_buff *skb) | |
9fb9cbb1 | 879 | { |
b2a15a60 | 880 | struct nf_conn *ct, *tmpl = NULL; |
9fb9cbb1 YK |
881 | enum ip_conntrack_info ctinfo; |
882 | struct nf_conntrack_l3proto *l3proto; | |
605dcad6 | 883 | struct nf_conntrack_l4proto *l4proto; |
9fb9cbb1 YK |
884 | unsigned int dataoff; |
885 | u_int8_t protonum; | |
886 | int set_reply = 0; | |
887 | int ret; | |
888 | ||
3db05fea | 889 | if (skb->nfct) { |
b2a15a60 PM |
890 | /* Previously seen (loopback or untracked)? Ignore. */ |
891 | tmpl = (struct nf_conn *)skb->nfct; | |
892 | if (!nf_ct_is_template(tmpl)) { | |
893 | NF_CT_STAT_INC_ATOMIC(net, ignore); | |
894 | return NF_ACCEPT; | |
895 | } | |
896 | skb->nfct = NULL; | |
9fb9cbb1 YK |
897 | } |
898 | ||
923f4902 | 899 | /* rcu_read_lock()ed by nf_hook_slow */ |
76108cea | 900 | l3proto = __nf_ct_l3proto_find(pf); |
3db05fea | 901 | ret = l3proto->get_l4proto(skb, skb_network_offset(skb), |
ffc30690 YK |
902 | &dataoff, &protonum); |
903 | if (ret <= 0) { | |
25985edc | 904 | pr_debug("not prepared to track yet or error occurred\n"); |
0d55af87 AD |
905 | NF_CT_STAT_INC_ATOMIC(net, error); |
906 | NF_CT_STAT_INC_ATOMIC(net, invalid); | |
b2a15a60 PM |
907 | ret = -ret; |
908 | goto out; | |
9fb9cbb1 YK |
909 | } |
910 | ||
76108cea | 911 | l4proto = __nf_ct_l4proto_find(pf, protonum); |
9fb9cbb1 YK |
912 | |
913 | /* It may be an special packet, error, unclean... | |
914 | * inverse of the return code tells to the netfilter | |
915 | * core what to do with the packet. */ | |
74c51a14 | 916 | if (l4proto->error != NULL) { |
8fea97ec PM |
917 | ret = l4proto->error(net, tmpl, skb, dataoff, &ctinfo, |
918 | pf, hooknum); | |
74c51a14 | 919 | if (ret <= 0) { |
0d55af87 AD |
920 | NF_CT_STAT_INC_ATOMIC(net, error); |
921 | NF_CT_STAT_INC_ATOMIC(net, invalid); | |
b2a15a60 PM |
922 | ret = -ret; |
923 | goto out; | |
74c51a14 | 924 | } |
88ed01d1 PNA |
925 | /* ICMP[v6] protocol trackers may assign one conntrack. */ |
926 | if (skb->nfct) | |
927 | goto out; | |
9fb9cbb1 YK |
928 | } |
929 | ||
b2a15a60 | 930 | ct = resolve_normal_ct(net, tmpl, skb, dataoff, pf, protonum, |
a702a65f | 931 | l3proto, l4proto, &set_reply, &ctinfo); |
9fb9cbb1 YK |
932 | if (!ct) { |
933 | /* Not valid part of a connection */ | |
0d55af87 | 934 | NF_CT_STAT_INC_ATOMIC(net, invalid); |
b2a15a60 PM |
935 | ret = NF_ACCEPT; |
936 | goto out; | |
9fb9cbb1 YK |
937 | } |
938 | ||
939 | if (IS_ERR(ct)) { | |
940 | /* Too stressed to deal. */ | |
0d55af87 | 941 | NF_CT_STAT_INC_ATOMIC(net, drop); |
b2a15a60 PM |
942 | ret = NF_DROP; |
943 | goto out; | |
9fb9cbb1 YK |
944 | } |
945 | ||
3db05fea | 946 | NF_CT_ASSERT(skb->nfct); |
9fb9cbb1 | 947 | |
3db05fea | 948 | ret = l4proto->packet(ct, skb, dataoff, ctinfo, pf, hooknum); |
ec8d5409 | 949 | if (ret <= 0) { |
9fb9cbb1 YK |
950 | /* Invalid: inverse of the return code tells |
951 | * the netfilter core what to do */ | |
0d53778e | 952 | pr_debug("nf_conntrack_in: Can't track with proto module\n"); |
3db05fea HX |
953 | nf_conntrack_put(skb->nfct); |
954 | skb->nfct = NULL; | |
0d55af87 | 955 | NF_CT_STAT_INC_ATOMIC(net, invalid); |
7d1e0459 PNA |
956 | if (ret == -NF_DROP) |
957 | NF_CT_STAT_INC_ATOMIC(net, drop); | |
b2a15a60 PM |
958 | ret = -ret; |
959 | goto out; | |
9fb9cbb1 YK |
960 | } |
961 | ||
962 | if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status)) | |
858b3133 | 963 | nf_conntrack_event_cache(IPCT_REPLY, ct); |
b2a15a60 | 964 | out: |
c3174286 PNA |
965 | if (tmpl) { |
966 | /* Special case: we have to repeat this hook, assign the | |
967 | * template again to this packet. We assume that this packet | |
968 | * has no conntrack assigned. This is used by nf_ct_tcp. */ | |
969 | if (ret == NF_REPEAT) | |
970 | skb->nfct = (struct nf_conntrack *)tmpl; | |
971 | else | |
972 | nf_ct_put(tmpl); | |
973 | } | |
9fb9cbb1 YK |
974 | |
975 | return ret; | |
976 | } | |
13b18339 | 977 | EXPORT_SYMBOL_GPL(nf_conntrack_in); |
9fb9cbb1 | 978 | |
5f2b4c90 JE |
979 | bool nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse, |
980 | const struct nf_conntrack_tuple *orig) | |
9fb9cbb1 | 981 | { |
5f2b4c90 | 982 | bool ret; |
923f4902 PM |
983 | |
984 | rcu_read_lock(); | |
985 | ret = nf_ct_invert_tuple(inverse, orig, | |
986 | __nf_ct_l3proto_find(orig->src.l3num), | |
987 | __nf_ct_l4proto_find(orig->src.l3num, | |
988 | orig->dst.protonum)); | |
989 | rcu_read_unlock(); | |
990 | return ret; | |
9fb9cbb1 | 991 | } |
13b18339 | 992 | EXPORT_SYMBOL_GPL(nf_ct_invert_tuplepr); |
9fb9cbb1 | 993 | |
5b1158e9 JK |
994 | /* Alter reply tuple (maybe alter helper). This is for NAT, and is |
995 | implicitly racy: see __nf_conntrack_confirm */ | |
996 | void nf_conntrack_alter_reply(struct nf_conn *ct, | |
997 | const struct nf_conntrack_tuple *newreply) | |
998 | { | |
999 | struct nf_conn_help *help = nfct_help(ct); | |
1000 | ||
5b1158e9 JK |
1001 | /* Should be unconfirmed, so not in hash table yet */ |
1002 | NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); | |
1003 | ||
0d53778e | 1004 | pr_debug("Altering reply tuple of %p to ", ct); |
3c9fba65 | 1005 | nf_ct_dump_tuple(newreply); |
5b1158e9 JK |
1006 | |
1007 | ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply; | |
ef1a5a50 | 1008 | if (ct->master || (help && !hlist_empty(&help->expectations))) |
c52fbb41 | 1009 | return; |
ceceae1b | 1010 | |
c52fbb41 | 1011 | rcu_read_lock(); |
b2a15a60 | 1012 | __nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC); |
c52fbb41 | 1013 | rcu_read_unlock(); |
5b1158e9 | 1014 | } |
13b18339 | 1015 | EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply); |
5b1158e9 | 1016 | |
9fb9cbb1 YK |
1017 | /* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */ |
1018 | void __nf_ct_refresh_acct(struct nf_conn *ct, | |
1019 | enum ip_conntrack_info ctinfo, | |
1020 | const struct sk_buff *skb, | |
1021 | unsigned long extra_jiffies, | |
1022 | int do_acct) | |
1023 | { | |
9fb9cbb1 YK |
1024 | NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct); |
1025 | NF_CT_ASSERT(skb); | |
1026 | ||
997ae831 | 1027 | /* Only update if this is not a fixed timeout */ |
47d95045 PM |
1028 | if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status)) |
1029 | goto acct; | |
997ae831 | 1030 | |
9fb9cbb1 YK |
1031 | /* If not in hash table, timer will not be active yet */ |
1032 | if (!nf_ct_is_confirmed(ct)) { | |
1033 | ct->timeout.expires = extra_jiffies; | |
9fb9cbb1 | 1034 | } else { |
be00c8e4 MJ |
1035 | unsigned long newtime = jiffies + extra_jiffies; |
1036 | ||
1037 | /* Only update the timeout if the new timeout is at least | |
1038 | HZ jiffies from the old timeout. Need del_timer for race | |
1039 | avoidance (may already be dying). */ | |
65cb9fda PM |
1040 | if (newtime - ct->timeout.expires >= HZ) |
1041 | mod_timer_pending(&ct->timeout, newtime); | |
9fb9cbb1 YK |
1042 | } |
1043 | ||
47d95045 | 1044 | acct: |
9fb9cbb1 | 1045 | if (do_acct) { |
58401572 | 1046 | struct nf_conn_counter *acct; |
3ffd5eeb | 1047 | |
58401572 KPO |
1048 | acct = nf_conn_acct_find(ct); |
1049 | if (acct) { | |
65cb9fda | 1050 | spin_lock_bh(&ct->lock); |
58401572 | 1051 | acct[CTINFO2DIR(ctinfo)].packets++; |
6661481d | 1052 | acct[CTINFO2DIR(ctinfo)].bytes += skb->len; |
65cb9fda | 1053 | spin_unlock_bh(&ct->lock); |
58401572 | 1054 | } |
9fb9cbb1 | 1055 | } |
9fb9cbb1 | 1056 | } |
13b18339 | 1057 | EXPORT_SYMBOL_GPL(__nf_ct_refresh_acct); |
9fb9cbb1 | 1058 | |
4c889498 DM |
1059 | bool __nf_ct_kill_acct(struct nf_conn *ct, |
1060 | enum ip_conntrack_info ctinfo, | |
1061 | const struct sk_buff *skb, | |
1062 | int do_acct) | |
51091764 | 1063 | { |
718d4ad9 | 1064 | if (do_acct) { |
58401572 KPO |
1065 | struct nf_conn_counter *acct; |
1066 | ||
58401572 KPO |
1067 | acct = nf_conn_acct_find(ct); |
1068 | if (acct) { | |
65cb9fda | 1069 | spin_lock_bh(&ct->lock); |
58401572 KPO |
1070 | acct[CTINFO2DIR(ctinfo)].packets++; |
1071 | acct[CTINFO2DIR(ctinfo)].bytes += | |
1072 | skb->len - skb_network_offset(skb); | |
65cb9fda | 1073 | spin_unlock_bh(&ct->lock); |
58401572 | 1074 | } |
718d4ad9 | 1075 | } |
58401572 | 1076 | |
4c889498 | 1077 | if (del_timer(&ct->timeout)) { |
51091764 | 1078 | ct->timeout.function((unsigned long)ct); |
4c889498 DM |
1079 | return true; |
1080 | } | |
1081 | return false; | |
51091764 | 1082 | } |
718d4ad9 | 1083 | EXPORT_SYMBOL_GPL(__nf_ct_kill_acct); |
51091764 | 1084 | |
5d0aa2cc PM |
1085 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1086 | static struct nf_ct_ext_type nf_ct_zone_extend __read_mostly = { | |
1087 | .len = sizeof(struct nf_conntrack_zone), | |
1088 | .align = __alignof__(struct nf_conntrack_zone), | |
1089 | .id = NF_CT_EXT_ZONE, | |
1090 | }; | |
1091 | #endif | |
1092 | ||
e281db5c | 1093 | #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) |
c1d10adb PNA |
1094 | |
1095 | #include <linux/netfilter/nfnetlink.h> | |
1096 | #include <linux/netfilter/nfnetlink_conntrack.h> | |
57b47a53 IM |
1097 | #include <linux/mutex.h> |
1098 | ||
c1d10adb PNA |
1099 | /* Generic function for tcp/udp/sctp/dccp and alike. This needs to be |
1100 | * in ip_conntrack_core, since we don't want the protocols to autoload | |
1101 | * or depend on ctnetlink */ | |
fdf70832 | 1102 | int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, |
c1d10adb PNA |
1103 | const struct nf_conntrack_tuple *tuple) |
1104 | { | |
77236b6e PM |
1105 | NLA_PUT_BE16(skb, CTA_PROTO_SRC_PORT, tuple->src.u.tcp.port); |
1106 | NLA_PUT_BE16(skb, CTA_PROTO_DST_PORT, tuple->dst.u.tcp.port); | |
c1d10adb PNA |
1107 | return 0; |
1108 | ||
df6fb868 | 1109 | nla_put_failure: |
c1d10adb PNA |
1110 | return -1; |
1111 | } | |
fdf70832 | 1112 | EXPORT_SYMBOL_GPL(nf_ct_port_tuple_to_nlattr); |
c1d10adb | 1113 | |
f73e924c PM |
1114 | const struct nla_policy nf_ct_port_nla_policy[CTA_PROTO_MAX+1] = { |
1115 | [CTA_PROTO_SRC_PORT] = { .type = NLA_U16 }, | |
1116 | [CTA_PROTO_DST_PORT] = { .type = NLA_U16 }, | |
c1d10adb | 1117 | }; |
f73e924c | 1118 | EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy); |
c1d10adb | 1119 | |
fdf70832 | 1120 | int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], |
c1d10adb PNA |
1121 | struct nf_conntrack_tuple *t) |
1122 | { | |
df6fb868 | 1123 | if (!tb[CTA_PROTO_SRC_PORT] || !tb[CTA_PROTO_DST_PORT]) |
c1d10adb PNA |
1124 | return -EINVAL; |
1125 | ||
77236b6e PM |
1126 | t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]); |
1127 | t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]); | |
c1d10adb PNA |
1128 | |
1129 | return 0; | |
1130 | } | |
fdf70832 | 1131 | EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_to_tuple); |
5c0de29d HE |
1132 | |
1133 | int nf_ct_port_nlattr_tuple_size(void) | |
1134 | { | |
1135 | return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1); | |
1136 | } | |
1137 | EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_tuple_size); | |
c1d10adb PNA |
1138 | #endif |
1139 | ||
9fb9cbb1 | 1140 | /* Used by ipt_REJECT and ip6t_REJECT. */ |
b334aadc | 1141 | static void nf_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb) |
9fb9cbb1 YK |
1142 | { |
1143 | struct nf_conn *ct; | |
1144 | enum ip_conntrack_info ctinfo; | |
1145 | ||
1146 | /* This ICMP is in reverse direction to the packet which caused it */ | |
1147 | ct = nf_ct_get(skb, &ctinfo); | |
1148 | if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) | |
fb048833 | 1149 | ctinfo = IP_CT_RELATED_REPLY; |
9fb9cbb1 YK |
1150 | else |
1151 | ctinfo = IP_CT_RELATED; | |
1152 | ||
1153 | /* Attach to new skbuff, and increment count */ | |
1154 | nskb->nfct = &ct->ct_general; | |
1155 | nskb->nfctinfo = ctinfo; | |
1156 | nf_conntrack_get(nskb->nfct); | |
1157 | } | |
1158 | ||
9fb9cbb1 | 1159 | /* Bring out ya dead! */ |
df0933dc | 1160 | static struct nf_conn * |
400dad39 | 1161 | get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data), |
9fb9cbb1 YK |
1162 | void *data, unsigned int *bucket) |
1163 | { | |
df0933dc PM |
1164 | struct nf_conntrack_tuple_hash *h; |
1165 | struct nf_conn *ct; | |
ea781f19 | 1166 | struct hlist_nulls_node *n; |
9fb9cbb1 | 1167 | |
f8ba1aff | 1168 | spin_lock_bh(&nf_conntrack_lock); |
d696c7bd | 1169 | for (; *bucket < net->ct.htable_size; (*bucket)++) { |
ea781f19 | 1170 | hlist_nulls_for_each_entry(h, n, &net->ct.hash[*bucket], hnnode) { |
df0933dc PM |
1171 | ct = nf_ct_tuplehash_to_ctrack(h); |
1172 | if (iter(ct, data)) | |
1173 | goto found; | |
1174 | } | |
601e68e1 | 1175 | } |
ea781f19 | 1176 | hlist_nulls_for_each_entry(h, n, &net->ct.unconfirmed, hnnode) { |
df0933dc PM |
1177 | ct = nf_ct_tuplehash_to_ctrack(h); |
1178 | if (iter(ct, data)) | |
ec68e97d | 1179 | set_bit(IPS_DYING_BIT, &ct->status); |
df0933dc | 1180 | } |
f8ba1aff | 1181 | spin_unlock_bh(&nf_conntrack_lock); |
df0933dc PM |
1182 | return NULL; |
1183 | found: | |
c073e3fa | 1184 | atomic_inc(&ct->ct_general.use); |
f8ba1aff | 1185 | spin_unlock_bh(&nf_conntrack_lock); |
df0933dc | 1186 | return ct; |
9fb9cbb1 YK |
1187 | } |
1188 | ||
400dad39 AD |
1189 | void nf_ct_iterate_cleanup(struct net *net, |
1190 | int (*iter)(struct nf_conn *i, void *data), | |
1191 | void *data) | |
9fb9cbb1 | 1192 | { |
df0933dc | 1193 | struct nf_conn *ct; |
9fb9cbb1 YK |
1194 | unsigned int bucket = 0; |
1195 | ||
400dad39 | 1196 | while ((ct = get_next_corpse(net, iter, data, &bucket)) != NULL) { |
9fb9cbb1 YK |
1197 | /* Time to push up daises... */ |
1198 | if (del_timer(&ct->timeout)) | |
1199 | death_by_timeout((unsigned long)ct); | |
1200 | /* ... else the timer will get him soon. */ | |
1201 | ||
1202 | nf_ct_put(ct); | |
1203 | } | |
1204 | } | |
13b18339 | 1205 | EXPORT_SYMBOL_GPL(nf_ct_iterate_cleanup); |
9fb9cbb1 | 1206 | |
19abb7b0 PNA |
1207 | struct __nf_ct_flush_report { |
1208 | u32 pid; | |
1209 | int report; | |
1210 | }; | |
1211 | ||
274d383b | 1212 | static int kill_report(struct nf_conn *i, void *data) |
9fb9cbb1 | 1213 | { |
19abb7b0 | 1214 | struct __nf_ct_flush_report *fr = (struct __nf_ct_flush_report *)data; |
a992ca2a PNA |
1215 | struct nf_conn_tstamp *tstamp; |
1216 | ||
1217 | tstamp = nf_conn_tstamp_find(i); | |
1218 | if (tstamp && tstamp->stop == 0) | |
1219 | tstamp->stop = ktime_to_ns(ktime_get_real()); | |
19abb7b0 | 1220 | |
dd7669a9 PNA |
1221 | /* If we fail to deliver the event, death_by_timeout() will retry */ |
1222 | if (nf_conntrack_event_report(IPCT_DESTROY, i, | |
1223 | fr->pid, fr->report) < 0) | |
1224 | return 1; | |
1225 | ||
1226 | /* Avoid the delivery of the destroy event in death_by_timeout(). */ | |
1227 | set_bit(IPS_DYING_BIT, &i->status); | |
9fb9cbb1 YK |
1228 | return 1; |
1229 | } | |
1230 | ||
274d383b PNA |
1231 | static int kill_all(struct nf_conn *i, void *data) |
1232 | { | |
1233 | return 1; | |
1234 | } | |
1235 | ||
d862a662 | 1236 | void nf_ct_free_hashtable(void *hash, unsigned int size) |
9fb9cbb1 | 1237 | { |
d862a662 | 1238 | if (is_vmalloc_addr(hash)) |
9fb9cbb1 YK |
1239 | vfree(hash); |
1240 | else | |
601e68e1 | 1241 | free_pages((unsigned long)hash, |
f205c5e0 | 1242 | get_order(sizeof(struct hlist_head) * size)); |
9fb9cbb1 | 1243 | } |
ac565e5f | 1244 | EXPORT_SYMBOL_GPL(nf_ct_free_hashtable); |
9fb9cbb1 | 1245 | |
274d383b | 1246 | void nf_conntrack_flush_report(struct net *net, u32 pid, int report) |
c1d10adb | 1247 | { |
19abb7b0 PNA |
1248 | struct __nf_ct_flush_report fr = { |
1249 | .pid = pid, | |
1250 | .report = report, | |
1251 | }; | |
274d383b | 1252 | nf_ct_iterate_cleanup(net, kill_report, &fr); |
c1d10adb | 1253 | } |
274d383b | 1254 | EXPORT_SYMBOL_GPL(nf_conntrack_flush_report); |
c1d10adb | 1255 | |
ee254fa4 | 1256 | static void nf_ct_release_dying_list(struct net *net) |
dd7669a9 PNA |
1257 | { |
1258 | struct nf_conntrack_tuple_hash *h; | |
1259 | struct nf_conn *ct; | |
1260 | struct hlist_nulls_node *n; | |
1261 | ||
1262 | spin_lock_bh(&nf_conntrack_lock); | |
ee254fa4 | 1263 | hlist_nulls_for_each_entry(h, n, &net->ct.dying, hnnode) { |
dd7669a9 PNA |
1264 | ct = nf_ct_tuplehash_to_ctrack(h); |
1265 | /* never fails to remove them, no listeners at this point */ | |
1266 | nf_ct_kill(ct); | |
1267 | } | |
1268 | spin_unlock_bh(&nf_conntrack_lock); | |
1269 | } | |
1270 | ||
b3c5163f ED |
1271 | static int untrack_refs(void) |
1272 | { | |
1273 | int cnt = 0, cpu; | |
1274 | ||
1275 | for_each_possible_cpu(cpu) { | |
1276 | struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu); | |
1277 | ||
1278 | cnt += atomic_read(&ct->ct_general.use) - 1; | |
1279 | } | |
1280 | return cnt; | |
1281 | } | |
1282 | ||
08f6547d | 1283 | static void nf_conntrack_cleanup_init_net(void) |
9fb9cbb1 | 1284 | { |
b3c5163f | 1285 | while (untrack_refs() > 0) |
9edd7ca0 PM |
1286 | schedule(); |
1287 | ||
08f6547d AD |
1288 | nf_conntrack_helper_fini(); |
1289 | nf_conntrack_proto_fini(); | |
5d0aa2cc PM |
1290 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1291 | nf_ct_extend_unregister(&nf_ct_zone_extend); | |
1292 | #endif | |
08f6547d | 1293 | } |
9fb9cbb1 | 1294 | |
08f6547d AD |
1295 | static void nf_conntrack_cleanup_net(struct net *net) |
1296 | { | |
9fb9cbb1 | 1297 | i_see_dead_people: |
274d383b | 1298 | nf_ct_iterate_cleanup(net, kill_all, NULL); |
ee254fa4 | 1299 | nf_ct_release_dying_list(net); |
49ac8713 | 1300 | if (atomic_read(&net->ct.count) != 0) { |
9fb9cbb1 YK |
1301 | schedule(); |
1302 | goto i_see_dead_people; | |
1303 | } | |
1304 | ||
d862a662 | 1305 | nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size); |
a0891aa6 | 1306 | nf_conntrack_ecache_fini(net); |
fe8f661f | 1307 | nf_conntrack_tstamp_fini(net); |
d716a4df | 1308 | nf_conntrack_acct_fini(net); |
9b03f38d | 1309 | nf_conntrack_expect_fini(net); |
5b3501fa ED |
1310 | kmem_cache_destroy(net->ct.nf_conntrack_cachep); |
1311 | kfree(net->ct.slabname); | |
0d55af87 | 1312 | free_percpu(net->ct.stat); |
08f6547d AD |
1313 | } |
1314 | ||
1315 | /* Mishearing the voices in his head, our hero wonders how he's | |
1316 | supposed to kill the mall. */ | |
1317 | void nf_conntrack_cleanup(struct net *net) | |
1318 | { | |
1319 | if (net_eq(net, &init_net)) | |
1320 | rcu_assign_pointer(ip_ct_attach, NULL); | |
1321 | ||
1322 | /* This makes sure all current packets have passed through | |
1323 | netfilter framework. Roll on, two-stage module | |
1324 | delete... */ | |
1325 | synchronize_net(); | |
1326 | ||
1327 | nf_conntrack_cleanup_net(net); | |
1328 | ||
1329 | if (net_eq(net, &init_net)) { | |
1330 | rcu_assign_pointer(nf_ct_destroy, NULL); | |
1331 | nf_conntrack_cleanup_init_net(); | |
1332 | } | |
9fb9cbb1 YK |
1333 | } |
1334 | ||
d862a662 | 1335 | void *nf_ct_alloc_hashtable(unsigned int *sizep, int nulls) |
9fb9cbb1 | 1336 | { |
ea781f19 ED |
1337 | struct hlist_nulls_head *hash; |
1338 | unsigned int nr_slots, i; | |
1339 | size_t sz; | |
9fb9cbb1 | 1340 | |
ea781f19 ED |
1341 | BUILD_BUG_ON(sizeof(struct hlist_nulls_head) != sizeof(struct hlist_head)); |
1342 | nr_slots = *sizep = roundup(*sizep, PAGE_SIZE / sizeof(struct hlist_nulls_head)); | |
1343 | sz = nr_slots * sizeof(struct hlist_nulls_head); | |
1344 | hash = (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, | |
1345 | get_order(sz)); | |
601e68e1 | 1346 | if (!hash) { |
9fb9cbb1 | 1347 | printk(KERN_WARNING "nf_conntrack: falling back to vmalloc.\n"); |
6b1686a7 ED |
1348 | hash = __vmalloc(sz, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, |
1349 | PAGE_KERNEL); | |
9fb9cbb1 YK |
1350 | } |
1351 | ||
ea781f19 ED |
1352 | if (hash && nulls) |
1353 | for (i = 0; i < nr_slots; i++) | |
1354 | INIT_HLIST_NULLS_HEAD(&hash[i], i); | |
9fb9cbb1 YK |
1355 | |
1356 | return hash; | |
1357 | } | |
ac565e5f | 1358 | EXPORT_SYMBOL_GPL(nf_ct_alloc_hashtable); |
9fb9cbb1 | 1359 | |
fae718dd | 1360 | int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp) |
9fb9cbb1 | 1361 | { |
d862a662 | 1362 | int i, bucket; |
96eb24d7 | 1363 | unsigned int hashsize, old_size; |
ea781f19 | 1364 | struct hlist_nulls_head *hash, *old_hash; |
9fb9cbb1 | 1365 | struct nf_conntrack_tuple_hash *h; |
5d0aa2cc | 1366 | struct nf_conn *ct; |
9fb9cbb1 | 1367 | |
d696c7bd PM |
1368 | if (current->nsproxy->net_ns != &init_net) |
1369 | return -EOPNOTSUPP; | |
1370 | ||
9fb9cbb1 YK |
1371 | /* On boot, we can set this without any fancy locking. */ |
1372 | if (!nf_conntrack_htable_size) | |
1373 | return param_set_uint(val, kp); | |
1374 | ||
96eb24d7 | 1375 | hashsize = simple_strtoul(val, NULL, 0); |
9fb9cbb1 YK |
1376 | if (!hashsize) |
1377 | return -EINVAL; | |
1378 | ||
d862a662 | 1379 | hash = nf_ct_alloc_hashtable(&hashsize, 1); |
9fb9cbb1 YK |
1380 | if (!hash) |
1381 | return -ENOMEM; | |
1382 | ||
76507f69 PM |
1383 | /* Lookups in the old hash might happen in parallel, which means we |
1384 | * might get false negatives during connection lookup. New connections | |
1385 | * created because of a false negative won't make it into the hash | |
1386 | * though since that required taking the lock. | |
1387 | */ | |
f8ba1aff | 1388 | spin_lock_bh(&nf_conntrack_lock); |
d696c7bd | 1389 | for (i = 0; i < init_net.ct.htable_size; i++) { |
ea781f19 ED |
1390 | while (!hlist_nulls_empty(&init_net.ct.hash[i])) { |
1391 | h = hlist_nulls_entry(init_net.ct.hash[i].first, | |
1392 | struct nf_conntrack_tuple_hash, hnnode); | |
5d0aa2cc | 1393 | ct = nf_ct_tuplehash_to_ctrack(h); |
ea781f19 | 1394 | hlist_nulls_del_rcu(&h->hnnode); |
5d0aa2cc | 1395 | bucket = __hash_conntrack(&h->tuple, nf_ct_zone(ct), |
99f07e91 | 1396 | hashsize); |
ea781f19 | 1397 | hlist_nulls_add_head_rcu(&h->hnnode, &hash[bucket]); |
9fb9cbb1 YK |
1398 | } |
1399 | } | |
d696c7bd | 1400 | old_size = init_net.ct.htable_size; |
400dad39 | 1401 | old_hash = init_net.ct.hash; |
9fb9cbb1 | 1402 | |
d696c7bd | 1403 | init_net.ct.htable_size = nf_conntrack_htable_size = hashsize; |
400dad39 | 1404 | init_net.ct.hash = hash; |
f8ba1aff | 1405 | spin_unlock_bh(&nf_conntrack_lock); |
9fb9cbb1 | 1406 | |
d862a662 | 1407 | nf_ct_free_hashtable(old_hash, old_size); |
9fb9cbb1 YK |
1408 | return 0; |
1409 | } | |
fae718dd | 1410 | EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize); |
9fb9cbb1 | 1411 | |
fae718dd | 1412 | module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint, |
9fb9cbb1 YK |
1413 | &nf_conntrack_htable_size, 0600); |
1414 | ||
5bfddbd4 ED |
1415 | void nf_ct_untracked_status_or(unsigned long bits) |
1416 | { | |
b3c5163f ED |
1417 | int cpu; |
1418 | ||
1419 | for_each_possible_cpu(cpu) | |
1420 | per_cpu(nf_conntrack_untracked, cpu).status |= bits; | |
5bfddbd4 ED |
1421 | } |
1422 | EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or); | |
1423 | ||
08f6547d | 1424 | static int nf_conntrack_init_init_net(void) |
9fb9cbb1 | 1425 | { |
f205c5e0 | 1426 | int max_factor = 8; |
b3c5163f | 1427 | int ret, cpu; |
9fb9cbb1 YK |
1428 | |
1429 | /* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB | |
f205c5e0 | 1430 | * machine has 512 buckets. >= 1GB machines have 16384 buckets. */ |
9fb9cbb1 YK |
1431 | if (!nf_conntrack_htable_size) { |
1432 | nf_conntrack_htable_size | |
4481374c | 1433 | = (((totalram_pages << PAGE_SHIFT) / 16384) |
f205c5e0 | 1434 | / sizeof(struct hlist_head)); |
4481374c | 1435 | if (totalram_pages > (1024 * 1024 * 1024 / PAGE_SIZE)) |
f205c5e0 PM |
1436 | nf_conntrack_htable_size = 16384; |
1437 | if (nf_conntrack_htable_size < 32) | |
1438 | nf_conntrack_htable_size = 32; | |
1439 | ||
1440 | /* Use a max. factor of four by default to get the same max as | |
1441 | * with the old struct list_heads. When a table size is given | |
1442 | * we use the old value of 8 to avoid reducing the max. | |
1443 | * entries. */ | |
1444 | max_factor = 4; | |
9fb9cbb1 | 1445 | } |
f205c5e0 | 1446 | nf_conntrack_max = max_factor * nf_conntrack_htable_size; |
8e5105a0 | 1447 | |
654d0fbd | 1448 | printk(KERN_INFO "nf_conntrack version %s (%u buckets, %d max)\n", |
8e5105a0 PM |
1449 | NF_CONNTRACK_VERSION, nf_conntrack_htable_size, |
1450 | nf_conntrack_max); | |
1451 | ||
e9c1b084 PM |
1452 | ret = nf_conntrack_proto_init(); |
1453 | if (ret < 0) | |
08f6547d | 1454 | goto err_proto; |
933a41e7 | 1455 | |
ceceae1b YK |
1456 | ret = nf_conntrack_helper_init(); |
1457 | if (ret < 0) | |
08f6547d AD |
1458 | goto err_helper; |
1459 | ||
5d0aa2cc PM |
1460 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1461 | ret = nf_ct_extend_register(&nf_ct_zone_extend); | |
1462 | if (ret < 0) | |
1463 | goto err_extend; | |
1464 | #endif | |
9edd7ca0 | 1465 | /* Set up fake conntrack: to never be deleted, not in any hashes */ |
b3c5163f ED |
1466 | for_each_possible_cpu(cpu) { |
1467 | struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu); | |
b3c5163f ED |
1468 | write_pnet(&ct->ct_net, &init_net); |
1469 | atomic_set(&ct->ct_general.use, 1); | |
1470 | } | |
9edd7ca0 | 1471 | /* - and look it like as a confirmed connection */ |
5bfddbd4 | 1472 | nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED); |
08f6547d AD |
1473 | return 0; |
1474 | ||
5d0aa2cc PM |
1475 | #ifdef CONFIG_NF_CONNTRACK_ZONES |
1476 | err_extend: | |
1477 | nf_conntrack_helper_fini(); | |
1478 | #endif | |
08f6547d AD |
1479 | err_helper: |
1480 | nf_conntrack_proto_fini(); | |
1481 | err_proto: | |
08f6547d AD |
1482 | return ret; |
1483 | } | |
1484 | ||
8cc20198 ED |
1485 | /* |
1486 | * We need to use special "null" values, not used in hash table | |
1487 | */ | |
1488 | #define UNCONFIRMED_NULLS_VAL ((1<<30)+0) | |
1489 | #define DYING_NULLS_VAL ((1<<30)+1) | |
1490 | ||
08f6547d AD |
1491 | static int nf_conntrack_init_net(struct net *net) |
1492 | { | |
1493 | int ret; | |
ceceae1b | 1494 | |
08f6547d | 1495 | atomic_set(&net->ct.count, 0); |
8cc20198 ED |
1496 | INIT_HLIST_NULLS_HEAD(&net->ct.unconfirmed, UNCONFIRMED_NULLS_VAL); |
1497 | INIT_HLIST_NULLS_HEAD(&net->ct.dying, DYING_NULLS_VAL); | |
08f6547d AD |
1498 | net->ct.stat = alloc_percpu(struct ip_conntrack_stat); |
1499 | if (!net->ct.stat) { | |
1500 | ret = -ENOMEM; | |
1501 | goto err_stat; | |
1502 | } | |
5b3501fa ED |
1503 | |
1504 | net->ct.slabname = kasprintf(GFP_KERNEL, "nf_conntrack_%p", net); | |
1505 | if (!net->ct.slabname) { | |
1506 | ret = -ENOMEM; | |
1507 | goto err_slabname; | |
1508 | } | |
1509 | ||
1510 | net->ct.nf_conntrack_cachep = kmem_cache_create(net->ct.slabname, | |
1511 | sizeof(struct nf_conn), 0, | |
1512 | SLAB_DESTROY_BY_RCU, NULL); | |
1513 | if (!net->ct.nf_conntrack_cachep) { | |
1514 | printk(KERN_ERR "Unable to create nf_conn slab cache\n"); | |
1515 | ret = -ENOMEM; | |
1516 | goto err_cache; | |
1517 | } | |
d696c7bd PM |
1518 | |
1519 | net->ct.htable_size = nf_conntrack_htable_size; | |
d862a662 | 1520 | net->ct.hash = nf_ct_alloc_hashtable(&net->ct.htable_size, 1); |
08f6547d AD |
1521 | if (!net->ct.hash) { |
1522 | ret = -ENOMEM; | |
1523 | printk(KERN_ERR "Unable to create nf_conntrack_hash\n"); | |
1524 | goto err_hash; | |
1525 | } | |
1526 | ret = nf_conntrack_expect_init(net); | |
1527 | if (ret < 0) | |
1528 | goto err_expect; | |
d716a4df | 1529 | ret = nf_conntrack_acct_init(net); |
58401572 | 1530 | if (ret < 0) |
08f6547d | 1531 | goto err_acct; |
a992ca2a PNA |
1532 | ret = nf_conntrack_tstamp_init(net); |
1533 | if (ret < 0) | |
1534 | goto err_tstamp; | |
a0891aa6 PNA |
1535 | ret = nf_conntrack_ecache_init(net); |
1536 | if (ret < 0) | |
1537 | goto err_ecache; | |
7d3cdc6b | 1538 | |
08f6547d | 1539 | return 0; |
9fb9cbb1 | 1540 | |
a0891aa6 | 1541 | err_ecache: |
a992ca2a PNA |
1542 | nf_conntrack_tstamp_fini(net); |
1543 | err_tstamp: | |
a0891aa6 | 1544 | nf_conntrack_acct_fini(net); |
08f6547d | 1545 | err_acct: |
9b03f38d | 1546 | nf_conntrack_expect_fini(net); |
08f6547d | 1547 | err_expect: |
d862a662 | 1548 | nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size); |
6058fa6b | 1549 | err_hash: |
5b3501fa ED |
1550 | kmem_cache_destroy(net->ct.nf_conntrack_cachep); |
1551 | err_cache: | |
1552 | kfree(net->ct.slabname); | |
1553 | err_slabname: | |
0d55af87 AD |
1554 | free_percpu(net->ct.stat); |
1555 | err_stat: | |
08f6547d AD |
1556 | return ret; |
1557 | } | |
1558 | ||
f9dd09c7 JK |
1559 | s16 (*nf_ct_nat_offset)(const struct nf_conn *ct, |
1560 | enum ip_conntrack_dir dir, | |
1561 | u32 seq); | |
1562 | EXPORT_SYMBOL_GPL(nf_ct_nat_offset); | |
1563 | ||
08f6547d AD |
1564 | int nf_conntrack_init(struct net *net) |
1565 | { | |
1566 | int ret; | |
1567 | ||
1568 | if (net_eq(net, &init_net)) { | |
1569 | ret = nf_conntrack_init_init_net(); | |
1570 | if (ret < 0) | |
1571 | goto out_init_net; | |
1572 | } | |
1573 | ret = nf_conntrack_init_net(net); | |
1574 | if (ret < 0) | |
1575 | goto out_net; | |
1576 | ||
1577 | if (net_eq(net, &init_net)) { | |
1578 | /* For use by REJECT target */ | |
1579 | rcu_assign_pointer(ip_ct_attach, nf_conntrack_attach); | |
1580 | rcu_assign_pointer(nf_ct_destroy, destroy_conntrack); | |
f9dd09c7 JK |
1581 | |
1582 | /* Howto get NAT offsets */ | |
1583 | rcu_assign_pointer(nf_ct_nat_offset, NULL); | |
08f6547d AD |
1584 | } |
1585 | return 0; | |
1586 | ||
1587 | out_net: | |
1588 | if (net_eq(net, &init_net)) | |
1589 | nf_conntrack_cleanup_init_net(); | |
1590 | out_init_net: | |
1591 | return ret; | |
9fb9cbb1 | 1592 | } |