Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
| 6 | * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License version 2 as |
| 10 | * published by the Free Software Foundation. |
| 11 | * |
| 12 | * 23 Apr 2001: Harald Welte <laforge@gnumonks.org> |
| 13 | * - new API and handling of conntrack/nat helpers |
| 14 | * - now capable of multiple expectations for one master |
| 15 | * 16 Jul 2002: Harald Welte <laforge@gnumonks.org> |
| 16 | * - add usage/reference counts to ip_conntrack_expect |
| 17 | * - export ip_conntrack[_expect]_{find_get,put} functions |
| 18 | * */ |
| 19 | |
| 20 | #include <linux/config.h> |
| 21 | #include <linux/types.h> |
| 22 | #include <linux/icmp.h> |
| 23 | #include <linux/ip.h> |
| 24 | #include <linux/netfilter.h> |
| 25 | #include <linux/netfilter_ipv4.h> |
| 26 | #include <linux/module.h> |
| 27 | #include <linux/skbuff.h> |
| 28 | #include <linux/proc_fs.h> |
| 29 | #include <linux/vmalloc.h> |
| 30 | #include <net/checksum.h> |
| 31 | #include <net/ip.h> |
| 32 | #include <linux/stddef.h> |
| 33 | #include <linux/sysctl.h> |
| 34 | #include <linux/slab.h> |
| 35 | #include <linux/random.h> |
| 36 | #include <linux/jhash.h> |
| 37 | #include <linux/err.h> |
| 38 | #include <linux/percpu.h> |
| 39 | #include <linux/moduleparam.h> |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 40 | #include <linux/notifier.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 42 | /* ip_conntrack_lock protects the main hash table, protocol/helper/expected |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | registrations, conntrack timers*/ |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 44 | #define ASSERT_READ_LOCK(x) |
| 45 | #define ASSERT_WRITE_LOCK(x) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | |
| 47 | #include <linux/netfilter_ipv4/ip_conntrack.h> |
| 48 | #include <linux/netfilter_ipv4/ip_conntrack_protocol.h> |
| 49 | #include <linux/netfilter_ipv4/ip_conntrack_helper.h> |
| 50 | #include <linux/netfilter_ipv4/ip_conntrack_core.h> |
| 51 | #include <linux/netfilter_ipv4/listhelp.h> |
| 52 | |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 53 | #define IP_CONNTRACK_VERSION "2.4" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | |
| 55 | #if 0 |
| 56 | #define DEBUGP printk |
| 57 | #else |
| 58 | #define DEBUGP(format, args...) |
| 59 | #endif |
| 60 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 61 | DEFINE_RWLOCK(ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | |
| 63 | /* ip_conntrack_standalone needs this */ |
| 64 | atomic_t ip_conntrack_count = ATOMIC_INIT(0); |
| 65 | |
| 66 | void (*ip_conntrack_destroyed)(struct ip_conntrack *conntrack) = NULL; |
| 67 | LIST_HEAD(ip_conntrack_expect_list); |
| 68 | struct ip_conntrack_protocol *ip_ct_protos[MAX_IP_CT_PROTO]; |
| 69 | static LIST_HEAD(helpers); |
| 70 | unsigned int ip_conntrack_htable_size = 0; |
| 71 | int ip_conntrack_max; |
| 72 | struct list_head *ip_conntrack_hash; |
Eric Dumazet | ba89966 | 2005-08-26 12:05:31 -0700 | [diff] [blame] | 73 | static kmem_cache_t *ip_conntrack_cachep __read_mostly; |
| 74 | static kmem_cache_t *ip_conntrack_expect_cachep __read_mostly; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | struct ip_conntrack ip_conntrack_untracked; |
| 76 | unsigned int ip_ct_log_invalid; |
| 77 | static LIST_HEAD(unconfirmed); |
| 78 | static int ip_conntrack_vmalloc; |
| 79 | |
Pablo Neira Ayuso | 4e3882f | 2006-03-22 13:55:11 -0800 | [diff] [blame] | 80 | static unsigned int ip_conntrack_next_id; |
| 81 | static unsigned int ip_conntrack_expect_next_id; |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 82 | #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 83 | ATOMIC_NOTIFIER_HEAD(ip_conntrack_chain); |
| 84 | ATOMIC_NOTIFIER_HEAD(ip_conntrack_expect_chain); |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 85 | |
| 86 | DEFINE_PER_CPU(struct ip_conntrack_ecache, ip_conntrack_ecache); |
| 87 | |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 88 | /* deliver cached events and clear cache entry - must be called with locally |
| 89 | * disabled softirqs */ |
| 90 | static inline void |
| 91 | __ip_ct_deliver_cached_events(struct ip_conntrack_ecache *ecache) |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 92 | { |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 93 | DEBUGP("ecache: delivering events for %p\n", ecache->ct); |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 94 | if (is_confirmed(ecache->ct) && !is_dying(ecache->ct) && ecache->events) |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 95 | atomic_notifier_call_chain(&ip_conntrack_chain, ecache->events, |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 96 | ecache->ct); |
| 97 | ecache->events = 0; |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 98 | ip_conntrack_put(ecache->ct); |
| 99 | ecache->ct = NULL; |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 100 | } |
| 101 | |
| 102 | /* Deliver all cached events for a particular conntrack. This is called |
| 103 | * by code prior to async packet handling or freeing the skb */ |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 104 | void ip_ct_deliver_cached_events(const struct ip_conntrack *ct) |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 105 | { |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 106 | struct ip_conntrack_ecache *ecache; |
| 107 | |
| 108 | local_bh_disable(); |
| 109 | ecache = &__get_cpu_var(ip_conntrack_ecache); |
| 110 | if (ecache->ct == ct) |
| 111 | __ip_ct_deliver_cached_events(ecache); |
| 112 | local_bh_enable(); |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 113 | } |
| 114 | |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 115 | void __ip_ct_event_cache_init(struct ip_conntrack *ct) |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 116 | { |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 117 | struct ip_conntrack_ecache *ecache; |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 118 | |
| 119 | /* take care of delivering potentially old events */ |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 120 | ecache = &__get_cpu_var(ip_conntrack_ecache); |
| 121 | BUG_ON(ecache->ct == ct); |
| 122 | if (ecache->ct) |
| 123 | __ip_ct_deliver_cached_events(ecache); |
| 124 | /* initialize for this conntrack/packet */ |
| 125 | ecache->ct = ct; |
| 126 | nf_conntrack_get(&ct->ct_general); |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 127 | } |
| 128 | |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 129 | /* flush the event cache - touches other CPU's data and must not be called while |
| 130 | * packets are still passing through the code */ |
| 131 | static void ip_ct_event_cache_flush(void) |
| 132 | { |
| 133 | struct ip_conntrack_ecache *ecache; |
| 134 | int cpu; |
| 135 | |
| 136 | for_each_cpu(cpu) { |
| 137 | ecache = &per_cpu(ip_conntrack_ecache, cpu); |
| 138 | if (ecache->ct) |
| 139 | ip_conntrack_put(ecache->ct); |
| 140 | } |
| 141 | } |
| 142 | #else |
| 143 | static inline void ip_ct_event_cache_flush(void) {} |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 144 | #endif /* CONFIG_IP_NF_CONNTRACK_EVENTS */ |
| 145 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | DEFINE_PER_CPU(struct ip_conntrack_stat, ip_conntrack_stat); |
| 147 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | static int ip_conntrack_hash_rnd_initted; |
| 149 | static unsigned int ip_conntrack_hash_rnd; |
| 150 | |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 151 | static u_int32_t __hash_conntrack(const struct ip_conntrack_tuple *tuple, |
| 152 | unsigned int size, unsigned int rnd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | return (jhash_3words(tuple->src.ip, |
| 155 | (tuple->dst.ip ^ tuple->dst.protonum), |
| 156 | (tuple->src.u.all | (tuple->dst.u.all << 16)), |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 157 | rnd) % size); |
| 158 | } |
| 159 | |
| 160 | static u_int32_t |
| 161 | hash_conntrack(const struct ip_conntrack_tuple *tuple) |
| 162 | { |
| 163 | return __hash_conntrack(tuple, ip_conntrack_htable_size, |
| 164 | ip_conntrack_hash_rnd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | } |
| 166 | |
| 167 | int |
| 168 | ip_ct_get_tuple(const struct iphdr *iph, |
| 169 | const struct sk_buff *skb, |
| 170 | unsigned int dataoff, |
| 171 | struct ip_conntrack_tuple *tuple, |
| 172 | const struct ip_conntrack_protocol *protocol) |
| 173 | { |
| 174 | /* Never happen */ |
| 175 | if (iph->frag_off & htons(IP_OFFSET)) { |
| 176 | printk("ip_conntrack_core: Frag of proto %u.\n", |
| 177 | iph->protocol); |
| 178 | return 0; |
| 179 | } |
| 180 | |
| 181 | tuple->src.ip = iph->saddr; |
| 182 | tuple->dst.ip = iph->daddr; |
| 183 | tuple->dst.protonum = iph->protocol; |
| 184 | tuple->dst.dir = IP_CT_DIR_ORIGINAL; |
| 185 | |
| 186 | return protocol->pkt_to_tuple(skb, dataoff, tuple); |
| 187 | } |
| 188 | |
| 189 | int |
| 190 | ip_ct_invert_tuple(struct ip_conntrack_tuple *inverse, |
| 191 | const struct ip_conntrack_tuple *orig, |
| 192 | const struct ip_conntrack_protocol *protocol) |
| 193 | { |
| 194 | inverse->src.ip = orig->dst.ip; |
| 195 | inverse->dst.ip = orig->src.ip; |
| 196 | inverse->dst.protonum = orig->dst.protonum; |
| 197 | inverse->dst.dir = !orig->dst.dir; |
| 198 | |
| 199 | return protocol->invert_tuple(inverse, orig); |
| 200 | } |
| 201 | |
| 202 | |
| 203 | /* ip_conntrack_expect helper functions */ |
Pablo Neira Ayuso | 49719eb | 2005-09-06 15:10:46 -0700 | [diff] [blame] | 204 | void ip_ct_unlink_expect(struct ip_conntrack_expect *exp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | { |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 206 | ASSERT_WRITE_LOCK(&ip_conntrack_lock); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 207 | IP_NF_ASSERT(!timer_pending(&exp->timeout)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | list_del(&exp->list); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 209 | CONNTRACK_STAT_INC(expect_delete); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | exp->master->expecting--; |
Pablo Neira Ayuso | 37012f7 | 2005-08-09 20:06:11 -0700 | [diff] [blame] | 211 | ip_conntrack_expect_put(exp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | } |
| 213 | |
| 214 | static void expectation_timed_out(unsigned long ul_expect) |
| 215 | { |
| 216 | struct ip_conntrack_expect *exp = (void *)ul_expect; |
| 217 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 218 | write_lock_bh(&ip_conntrack_lock); |
Pablo Neira Ayuso | 49719eb | 2005-09-06 15:10:46 -0700 | [diff] [blame] | 219 | ip_ct_unlink_expect(exp); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 220 | write_unlock_bh(&ip_conntrack_lock); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 221 | ip_conntrack_expect_put(exp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | } |
| 223 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 224 | struct ip_conntrack_expect * |
| 225 | __ip_conntrack_expect_find(const struct ip_conntrack_tuple *tuple) |
| 226 | { |
| 227 | struct ip_conntrack_expect *i; |
| 228 | |
| 229 | list_for_each_entry(i, &ip_conntrack_expect_list, list) { |
| 230 | if (ip_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask)) { |
| 231 | atomic_inc(&i->use); |
| 232 | return i; |
| 233 | } |
| 234 | } |
| 235 | return NULL; |
| 236 | } |
| 237 | |
| 238 | /* Just find a expectation corresponding to a tuple. */ |
| 239 | struct ip_conntrack_expect * |
Patrick McHardy | a41bc00 | 2005-09-19 15:35:31 -0700 | [diff] [blame] | 240 | ip_conntrack_expect_find(const struct ip_conntrack_tuple *tuple) |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 241 | { |
| 242 | struct ip_conntrack_expect *i; |
| 243 | |
| 244 | read_lock_bh(&ip_conntrack_lock); |
| 245 | i = __ip_conntrack_expect_find(tuple); |
| 246 | read_unlock_bh(&ip_conntrack_lock); |
| 247 | |
| 248 | return i; |
| 249 | } |
| 250 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | /* If an expectation for this connection is found, it gets delete from |
| 252 | * global list then returned. */ |
| 253 | static struct ip_conntrack_expect * |
| 254 | find_expectation(const struct ip_conntrack_tuple *tuple) |
| 255 | { |
| 256 | struct ip_conntrack_expect *i; |
| 257 | |
| 258 | list_for_each_entry(i, &ip_conntrack_expect_list, list) { |
| 259 | /* If master is not in hash table yet (ie. packet hasn't left |
| 260 | this machine yet), how can other end know about expected? |
| 261 | Hence these are not the droids you are looking for (if |
| 262 | master ct never got confirmed, we'd hold a reference to it |
| 263 | and weird things would happen to future packets). */ |
| 264 | if (ip_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask) |
Patrick McHardy | 2248bcf | 2005-09-06 15:06:42 -0700 | [diff] [blame] | 265 | && is_confirmed(i->master)) { |
| 266 | if (i->flags & IP_CT_EXPECT_PERMANENT) { |
| 267 | atomic_inc(&i->use); |
| 268 | return i; |
| 269 | } else if (del_timer(&i->timeout)) { |
Pablo Neira Ayuso | 49719eb | 2005-09-06 15:10:46 -0700 | [diff] [blame] | 270 | ip_ct_unlink_expect(i); |
Patrick McHardy | 2248bcf | 2005-09-06 15:06:42 -0700 | [diff] [blame] | 271 | return i; |
| 272 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | } |
| 274 | } |
| 275 | return NULL; |
| 276 | } |
| 277 | |
| 278 | /* delete all expectations for this conntrack */ |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 279 | void ip_ct_remove_expectations(struct ip_conntrack *ct) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | { |
| 281 | struct ip_conntrack_expect *i, *tmp; |
| 282 | |
| 283 | /* Optimization: most connection never expect any others. */ |
| 284 | if (ct->expecting == 0) |
| 285 | return; |
| 286 | |
| 287 | list_for_each_entry_safe(i, tmp, &ip_conntrack_expect_list, list) { |
| 288 | if (i->master == ct && del_timer(&i->timeout)) { |
Pablo Neira Ayuso | 49719eb | 2005-09-06 15:10:46 -0700 | [diff] [blame] | 289 | ip_ct_unlink_expect(i); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 290 | ip_conntrack_expect_put(i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | } |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | static void |
| 296 | clean_from_lists(struct ip_conntrack *ct) |
| 297 | { |
| 298 | unsigned int ho, hr; |
| 299 | |
| 300 | DEBUGP("clean_from_lists(%p)\n", ct); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 301 | ASSERT_WRITE_LOCK(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | |
| 303 | ho = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); |
| 304 | hr = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| 305 | LIST_DELETE(&ip_conntrack_hash[ho], &ct->tuplehash[IP_CT_DIR_ORIGINAL]); |
| 306 | LIST_DELETE(&ip_conntrack_hash[hr], &ct->tuplehash[IP_CT_DIR_REPLY]); |
| 307 | |
| 308 | /* Destroy all pending expectations */ |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 309 | ip_ct_remove_expectations(ct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | } |
| 311 | |
| 312 | static void |
| 313 | destroy_conntrack(struct nf_conntrack *nfct) |
| 314 | { |
| 315 | struct ip_conntrack *ct = (struct ip_conntrack *)nfct; |
| 316 | struct ip_conntrack_protocol *proto; |
| 317 | |
| 318 | DEBUGP("destroy_conntrack(%p)\n", ct); |
| 319 | IP_NF_ASSERT(atomic_read(&nfct->use) == 0); |
| 320 | IP_NF_ASSERT(!timer_pending(&ct->timeout)); |
| 321 | |
Pablo Neira Ayuso | 14a50bb | 2005-08-09 20:05:52 -0700 | [diff] [blame] | 322 | ip_conntrack_event(IPCT_DESTROY, ct); |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 323 | set_bit(IPS_DYING_BIT, &ct->status); |
| 324 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | /* To make sure we don't get any weird locking issues here: |
| 326 | * destroy_conntrack() MUST NOT be called with a write lock |
| 327 | * to ip_conntrack_lock!!! -HW */ |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 328 | proto = __ip_conntrack_proto_find(ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | if (proto && proto->destroy) |
| 330 | proto->destroy(ct); |
| 331 | |
| 332 | if (ip_conntrack_destroyed) |
| 333 | ip_conntrack_destroyed(ct); |
| 334 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 335 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | /* Expectations will have been removed in clean_from_lists, |
| 337 | * except TFTP can create an expectation on the first packet, |
| 338 | * before connection is in the list, so we need to clean here, |
| 339 | * too. */ |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 340 | ip_ct_remove_expectations(ct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | |
| 342 | /* We overload first tuple to link into unconfirmed list. */ |
| 343 | if (!is_confirmed(ct)) { |
| 344 | BUG_ON(list_empty(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list)); |
| 345 | list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list); |
| 346 | } |
| 347 | |
| 348 | CONNTRACK_STAT_INC(delete); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 349 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | |
| 351 | if (ct->master) |
| 352 | ip_conntrack_put(ct->master); |
| 353 | |
| 354 | DEBUGP("destroy_conntrack: returning ct=%p to slab\n", ct); |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 355 | ip_conntrack_free(ct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | } |
| 357 | |
| 358 | static void death_by_timeout(unsigned long ul_conntrack) |
| 359 | { |
| 360 | struct ip_conntrack *ct = (void *)ul_conntrack; |
| 361 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 362 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | /* Inside lock so preempt is disabled on module removal path. |
| 364 | * Otherwise we can get spurious warnings. */ |
| 365 | CONNTRACK_STAT_INC(delete_list); |
| 366 | clean_from_lists(ct); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 367 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | ip_conntrack_put(ct); |
| 369 | } |
| 370 | |
| 371 | static inline int |
| 372 | conntrack_tuple_cmp(const struct ip_conntrack_tuple_hash *i, |
| 373 | const struct ip_conntrack_tuple *tuple, |
| 374 | const struct ip_conntrack *ignored_conntrack) |
| 375 | { |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 376 | ASSERT_READ_LOCK(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | return tuplehash_to_ctrack(i) != ignored_conntrack |
| 378 | && ip_ct_tuple_equal(tuple, &i->tuple); |
| 379 | } |
| 380 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 381 | struct ip_conntrack_tuple_hash * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 382 | __ip_conntrack_find(const struct ip_conntrack_tuple *tuple, |
| 383 | const struct ip_conntrack *ignored_conntrack) |
| 384 | { |
| 385 | struct ip_conntrack_tuple_hash *h; |
| 386 | unsigned int hash = hash_conntrack(tuple); |
| 387 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 388 | ASSERT_READ_LOCK(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | list_for_each_entry(h, &ip_conntrack_hash[hash], list) { |
| 390 | if (conntrack_tuple_cmp(h, tuple, ignored_conntrack)) { |
| 391 | CONNTRACK_STAT_INC(found); |
| 392 | return h; |
| 393 | } |
| 394 | CONNTRACK_STAT_INC(searched); |
| 395 | } |
| 396 | |
| 397 | return NULL; |
| 398 | } |
| 399 | |
| 400 | /* Find a connection corresponding to a tuple. */ |
| 401 | struct ip_conntrack_tuple_hash * |
| 402 | ip_conntrack_find_get(const struct ip_conntrack_tuple *tuple, |
| 403 | const struct ip_conntrack *ignored_conntrack) |
| 404 | { |
| 405 | struct ip_conntrack_tuple_hash *h; |
| 406 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 407 | read_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | h = __ip_conntrack_find(tuple, ignored_conntrack); |
| 409 | if (h) |
| 410 | atomic_inc(&tuplehash_to_ctrack(h)->ct_general.use); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 411 | read_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | |
| 413 | return h; |
| 414 | } |
| 415 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 416 | static void __ip_conntrack_hash_insert(struct ip_conntrack *ct, |
| 417 | unsigned int hash, |
| 418 | unsigned int repl_hash) |
| 419 | { |
| 420 | ct->id = ++ip_conntrack_next_id; |
| 421 | list_prepend(&ip_conntrack_hash[hash], |
| 422 | &ct->tuplehash[IP_CT_DIR_ORIGINAL].list); |
| 423 | list_prepend(&ip_conntrack_hash[repl_hash], |
| 424 | &ct->tuplehash[IP_CT_DIR_REPLY].list); |
| 425 | } |
| 426 | |
| 427 | void ip_conntrack_hash_insert(struct ip_conntrack *ct) |
| 428 | { |
| 429 | unsigned int hash, repl_hash; |
| 430 | |
| 431 | hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); |
| 432 | repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| 433 | |
| 434 | write_lock_bh(&ip_conntrack_lock); |
| 435 | __ip_conntrack_hash_insert(ct, hash, repl_hash); |
| 436 | write_unlock_bh(&ip_conntrack_lock); |
| 437 | } |
| 438 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | /* Confirm a connection given skb; places it in hash table */ |
| 440 | int |
| 441 | __ip_conntrack_confirm(struct sk_buff **pskb) |
| 442 | { |
| 443 | unsigned int hash, repl_hash; |
| 444 | struct ip_conntrack *ct; |
| 445 | enum ip_conntrack_info ctinfo; |
| 446 | |
| 447 | ct = ip_conntrack_get(*pskb, &ctinfo); |
| 448 | |
| 449 | /* ipt_REJECT uses ip_conntrack_attach to attach related |
| 450 | ICMP/TCP RST packets in other direction. Actual packet |
| 451 | which created connection will be IP_CT_NEW or for an |
| 452 | expected connection, IP_CT_RELATED. */ |
| 453 | if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) |
| 454 | return NF_ACCEPT; |
| 455 | |
| 456 | hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); |
| 457 | repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| 458 | |
| 459 | /* We're not in hash table, and we refuse to set up related |
| 460 | connections for unconfirmed conns. But packet copies and |
| 461 | REJECT will give spurious warnings here. */ |
| 462 | /* IP_NF_ASSERT(atomic_read(&ct->ct_general.use) == 1); */ |
| 463 | |
| 464 | /* No external references means noone else could have |
| 465 | confirmed us. */ |
| 466 | IP_NF_ASSERT(!is_confirmed(ct)); |
| 467 | DEBUGP("Confirming conntrack %p\n", ct); |
| 468 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 469 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | |
| 471 | /* See if there's one in the list already, including reverse: |
| 472 | NAT could have grabbed it without realizing, since we're |
| 473 | not in the hash. If there is, we lost race. */ |
| 474 | if (!LIST_FIND(&ip_conntrack_hash[hash], |
| 475 | conntrack_tuple_cmp, |
| 476 | struct ip_conntrack_tuple_hash *, |
| 477 | &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, NULL) |
| 478 | && !LIST_FIND(&ip_conntrack_hash[repl_hash], |
| 479 | conntrack_tuple_cmp, |
| 480 | struct ip_conntrack_tuple_hash *, |
| 481 | &ct->tuplehash[IP_CT_DIR_REPLY].tuple, NULL)) { |
| 482 | /* Remove from unconfirmed list */ |
| 483 | list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list); |
| 484 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 485 | __ip_conntrack_hash_insert(ct, hash, repl_hash); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | /* Timer relative to confirmation time, not original |
| 487 | setting time, otherwise we'd get timer wrap in |
| 488 | weird delay cases. */ |
| 489 | ct->timeout.expires += jiffies; |
| 490 | add_timer(&ct->timeout); |
| 491 | atomic_inc(&ct->ct_general.use); |
| 492 | set_bit(IPS_CONFIRMED_BIT, &ct->status); |
| 493 | CONNTRACK_STAT_INC(insert); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 494 | write_unlock_bh(&ip_conntrack_lock); |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 495 | if (ct->helper) |
| 496 | ip_conntrack_event_cache(IPCT_HELPER, *pskb); |
| 497 | #ifdef CONFIG_IP_NF_NAT_NEEDED |
| 498 | if (test_bit(IPS_SRC_NAT_DONE_BIT, &ct->status) || |
| 499 | test_bit(IPS_DST_NAT_DONE_BIT, &ct->status)) |
| 500 | ip_conntrack_event_cache(IPCT_NATINFO, *pskb); |
| 501 | #endif |
| 502 | ip_conntrack_event_cache(master_ct(ct) ? |
| 503 | IPCT_RELATED : IPCT_NEW, *pskb); |
| 504 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | return NF_ACCEPT; |
| 506 | } |
| 507 | |
| 508 | CONNTRACK_STAT_INC(insert_failed); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 509 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | |
| 511 | return NF_DROP; |
| 512 | } |
| 513 | |
| 514 | /* Returns true if a connection correspondings to the tuple (required |
| 515 | for NAT). */ |
| 516 | int |
| 517 | ip_conntrack_tuple_taken(const struct ip_conntrack_tuple *tuple, |
| 518 | const struct ip_conntrack *ignored_conntrack) |
| 519 | { |
| 520 | struct ip_conntrack_tuple_hash *h; |
| 521 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 522 | read_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | h = __ip_conntrack_find(tuple, ignored_conntrack); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 524 | read_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 525 | |
| 526 | return h != NULL; |
| 527 | } |
| 528 | |
| 529 | /* There's a small race here where we may free a just-assured |
| 530 | connection. Too bad: we're in trouble anyway. */ |
| 531 | static inline int unreplied(const struct ip_conntrack_tuple_hash *i) |
| 532 | { |
| 533 | return !(test_bit(IPS_ASSURED_BIT, &tuplehash_to_ctrack(i)->status)); |
| 534 | } |
| 535 | |
| 536 | static int early_drop(struct list_head *chain) |
| 537 | { |
| 538 | /* Traverse backwards: gives us oldest, which is roughly LRU */ |
| 539 | struct ip_conntrack_tuple_hash *h; |
| 540 | struct ip_conntrack *ct = NULL; |
| 541 | int dropped = 0; |
| 542 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 543 | read_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | h = LIST_FIND_B(chain, unreplied, struct ip_conntrack_tuple_hash *); |
| 545 | if (h) { |
| 546 | ct = tuplehash_to_ctrack(h); |
| 547 | atomic_inc(&ct->ct_general.use); |
| 548 | } |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 549 | read_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 550 | |
| 551 | if (!ct) |
| 552 | return dropped; |
| 553 | |
| 554 | if (del_timer(&ct->timeout)) { |
| 555 | death_by_timeout((unsigned long)ct); |
| 556 | dropped = 1; |
| 557 | CONNTRACK_STAT_INC(early_drop); |
| 558 | } |
| 559 | ip_conntrack_put(ct); |
| 560 | return dropped; |
| 561 | } |
| 562 | |
| 563 | static inline int helper_cmp(const struct ip_conntrack_helper *i, |
| 564 | const struct ip_conntrack_tuple *rtuple) |
| 565 | { |
| 566 | return ip_ct_tuple_mask_cmp(rtuple, &i->tuple, &i->mask); |
| 567 | } |
| 568 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 569 | static struct ip_conntrack_helper * |
| 570 | __ip_conntrack_helper_find( const struct ip_conntrack_tuple *tuple) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 571 | { |
| 572 | return LIST_FIND(&helpers, helper_cmp, |
| 573 | struct ip_conntrack_helper *, |
| 574 | tuple); |
| 575 | } |
| 576 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 577 | struct ip_conntrack_helper * |
| 578 | ip_conntrack_helper_find_get( const struct ip_conntrack_tuple *tuple) |
| 579 | { |
| 580 | struct ip_conntrack_helper *helper; |
| 581 | |
| 582 | /* need ip_conntrack_lock to assure that helper exists until |
| 583 | * try_module_get() is called */ |
| 584 | read_lock_bh(&ip_conntrack_lock); |
| 585 | |
| 586 | helper = __ip_conntrack_helper_find(tuple); |
| 587 | if (helper) { |
| 588 | /* need to increase module usage count to assure helper will |
| 589 | * not go away while the caller is e.g. busy putting a |
| 590 | * conntrack in the hash that uses the helper */ |
| 591 | if (!try_module_get(helper->me)) |
| 592 | helper = NULL; |
| 593 | } |
| 594 | |
| 595 | read_unlock_bh(&ip_conntrack_lock); |
| 596 | |
| 597 | return helper; |
| 598 | } |
| 599 | |
| 600 | void ip_conntrack_helper_put(struct ip_conntrack_helper *helper) |
| 601 | { |
| 602 | module_put(helper->me); |
| 603 | } |
| 604 | |
| 605 | struct ip_conntrack_protocol * |
| 606 | __ip_conntrack_proto_find(u_int8_t protocol) |
| 607 | { |
| 608 | return ip_ct_protos[protocol]; |
| 609 | } |
| 610 | |
| 611 | /* this is guaranteed to always return a valid protocol helper, since |
| 612 | * it falls back to generic_protocol */ |
| 613 | struct ip_conntrack_protocol * |
| 614 | ip_conntrack_proto_find_get(u_int8_t protocol) |
| 615 | { |
| 616 | struct ip_conntrack_protocol *p; |
| 617 | |
| 618 | preempt_disable(); |
| 619 | p = __ip_conntrack_proto_find(protocol); |
| 620 | if (p) { |
| 621 | if (!try_module_get(p->me)) |
| 622 | p = &ip_conntrack_generic_protocol; |
| 623 | } |
| 624 | preempt_enable(); |
| 625 | |
| 626 | return p; |
| 627 | } |
| 628 | |
| 629 | void ip_conntrack_proto_put(struct ip_conntrack_protocol *p) |
| 630 | { |
| 631 | module_put(p->me); |
| 632 | } |
| 633 | |
| 634 | struct ip_conntrack *ip_conntrack_alloc(struct ip_conntrack_tuple *orig, |
| 635 | struct ip_conntrack_tuple *repl) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 636 | { |
| 637 | struct ip_conntrack *conntrack; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | |
| 639 | if (!ip_conntrack_hash_rnd_initted) { |
| 640 | get_random_bytes(&ip_conntrack_hash_rnd, 4); |
| 641 | ip_conntrack_hash_rnd_initted = 1; |
| 642 | } |
| 643 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | if (ip_conntrack_max |
| 645 | && atomic_read(&ip_conntrack_count) >= ip_conntrack_max) { |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 646 | unsigned int hash = hash_conntrack(orig); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | /* Try dropping from this hash chain. */ |
| 648 | if (!early_drop(&ip_conntrack_hash[hash])) { |
| 649 | if (net_ratelimit()) |
| 650 | printk(KERN_WARNING |
| 651 | "ip_conntrack: table full, dropping" |
| 652 | " packet.\n"); |
| 653 | return ERR_PTR(-ENOMEM); |
| 654 | } |
| 655 | } |
| 656 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | conntrack = kmem_cache_alloc(ip_conntrack_cachep, GFP_ATOMIC); |
| 658 | if (!conntrack) { |
| 659 | DEBUGP("Can't allocate conntrack.\n"); |
Yasuyuki Kozakai | 7663f18 | 2005-08-09 20:24:15 -0700 | [diff] [blame] | 660 | return ERR_PTR(-ENOMEM); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 661 | } |
| 662 | |
| 663 | memset(conntrack, 0, sizeof(*conntrack)); |
| 664 | atomic_set(&conntrack->ct_general.use, 1); |
| 665 | conntrack->ct_general.destroy = destroy_conntrack; |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 666 | conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig; |
| 667 | conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | /* Don't set timer yet: wait for confirmation */ |
| 669 | init_timer(&conntrack->timeout); |
| 670 | conntrack->timeout.data = (unsigned long)conntrack; |
| 671 | conntrack->timeout.function = death_by_timeout; |
| 672 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 673 | atomic_inc(&ip_conntrack_count); |
| 674 | |
| 675 | return conntrack; |
| 676 | } |
| 677 | |
| 678 | void |
| 679 | ip_conntrack_free(struct ip_conntrack *conntrack) |
| 680 | { |
| 681 | atomic_dec(&ip_conntrack_count); |
| 682 | kmem_cache_free(ip_conntrack_cachep, conntrack); |
| 683 | } |
| 684 | |
| 685 | /* Allocate a new conntrack: we return -ENOMEM if classification |
| 686 | * failed due to stress. Otherwise it really is unclassifiable */ |
| 687 | static struct ip_conntrack_tuple_hash * |
| 688 | init_conntrack(struct ip_conntrack_tuple *tuple, |
| 689 | struct ip_conntrack_protocol *protocol, |
| 690 | struct sk_buff *skb) |
| 691 | { |
| 692 | struct ip_conntrack *conntrack; |
| 693 | struct ip_conntrack_tuple repl_tuple; |
| 694 | struct ip_conntrack_expect *exp; |
| 695 | |
| 696 | if (!ip_ct_invert_tuple(&repl_tuple, tuple, protocol)) { |
| 697 | DEBUGP("Can't invert tuple.\n"); |
| 698 | return NULL; |
| 699 | } |
| 700 | |
Yasuyuki Kozakai | 7663f18 | 2005-08-09 20:24:15 -0700 | [diff] [blame] | 701 | conntrack = ip_conntrack_alloc(tuple, &repl_tuple); |
| 702 | if (conntrack == NULL || IS_ERR(conntrack)) |
| 703 | return (struct ip_conntrack_tuple_hash *)conntrack; |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 704 | |
| 705 | if (!protocol->new(conntrack, skb)) { |
| 706 | ip_conntrack_free(conntrack); |
| 707 | return NULL; |
| 708 | } |
| 709 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 710 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | exp = find_expectation(tuple); |
| 712 | |
| 713 | if (exp) { |
| 714 | DEBUGP("conntrack: expectation arrives ct=%p exp=%p\n", |
| 715 | conntrack, exp); |
| 716 | /* Welcome, Mr. Bond. We've been expecting you... */ |
| 717 | __set_bit(IPS_EXPECTED_BIT, &conntrack->status); |
| 718 | conntrack->master = exp->master; |
Nick Sillik | 7cee432 | 2005-07-27 14:46:03 -0700 | [diff] [blame] | 719 | #ifdef CONFIG_IP_NF_CONNTRACK_MARK |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | conntrack->mark = exp->master->mark; |
| 721 | #endif |
Harald Welte | 1f494c0 | 2005-07-30 17:44:07 -0700 | [diff] [blame] | 722 | #if defined(CONFIG_IP_NF_TARGET_MASQUERADE) || \ |
| 723 | defined(CONFIG_IP_NF_TARGET_MASQUERADE_MODULE) |
| 724 | /* this is ugly, but there is no other place where to put it */ |
| 725 | conntrack->nat.masq_index = exp->master->nat.masq_index; |
| 726 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | nf_conntrack_get(&conntrack->master->ct_general); |
| 728 | CONNTRACK_STAT_INC(expect_new); |
| 729 | } else { |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 730 | conntrack->helper = __ip_conntrack_helper_find(&repl_tuple); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | |
| 732 | CONNTRACK_STAT_INC(new); |
| 733 | } |
| 734 | |
| 735 | /* Overload tuple linked list to put us in unconfirmed list. */ |
| 736 | list_add(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].list, &unconfirmed); |
| 737 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 738 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 739 | |
| 740 | if (exp) { |
| 741 | if (exp->expectfn) |
| 742 | exp->expectfn(conntrack, exp); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 743 | ip_conntrack_expect_put(exp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | } |
| 745 | |
| 746 | return &conntrack->tuplehash[IP_CT_DIR_ORIGINAL]; |
| 747 | } |
| 748 | |
| 749 | /* On success, returns conntrack ptr, sets skb->nfct and ctinfo */ |
| 750 | static inline struct ip_conntrack * |
| 751 | resolve_normal_ct(struct sk_buff *skb, |
| 752 | struct ip_conntrack_protocol *proto, |
| 753 | int *set_reply, |
| 754 | unsigned int hooknum, |
| 755 | enum ip_conntrack_info *ctinfo) |
| 756 | { |
| 757 | struct ip_conntrack_tuple tuple; |
| 758 | struct ip_conntrack_tuple_hash *h; |
| 759 | struct ip_conntrack *ct; |
| 760 | |
| 761 | IP_NF_ASSERT((skb->nh.iph->frag_off & htons(IP_OFFSET)) == 0); |
| 762 | |
| 763 | if (!ip_ct_get_tuple(skb->nh.iph, skb, skb->nh.iph->ihl*4, |
| 764 | &tuple,proto)) |
| 765 | return NULL; |
| 766 | |
| 767 | /* look for tuple match */ |
| 768 | h = ip_conntrack_find_get(&tuple, NULL); |
| 769 | if (!h) { |
| 770 | h = init_conntrack(&tuple, proto, skb); |
| 771 | if (!h) |
| 772 | return NULL; |
| 773 | if (IS_ERR(h)) |
| 774 | return (void *)h; |
| 775 | } |
| 776 | ct = tuplehash_to_ctrack(h); |
| 777 | |
| 778 | /* It exists; we have (non-exclusive) reference. */ |
| 779 | if (DIRECTION(h) == IP_CT_DIR_REPLY) { |
| 780 | *ctinfo = IP_CT_ESTABLISHED + IP_CT_IS_REPLY; |
| 781 | /* Please set reply bit if this packet OK */ |
| 782 | *set_reply = 1; |
| 783 | } else { |
| 784 | /* Once we've had two way comms, always ESTABLISHED. */ |
| 785 | if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { |
| 786 | DEBUGP("ip_conntrack_in: normal packet for %p\n", |
| 787 | ct); |
| 788 | *ctinfo = IP_CT_ESTABLISHED; |
| 789 | } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) { |
| 790 | DEBUGP("ip_conntrack_in: related packet for %p\n", |
| 791 | ct); |
| 792 | *ctinfo = IP_CT_RELATED; |
| 793 | } else { |
| 794 | DEBUGP("ip_conntrack_in: new packet for %p\n", |
| 795 | ct); |
| 796 | *ctinfo = IP_CT_NEW; |
| 797 | } |
| 798 | *set_reply = 0; |
| 799 | } |
| 800 | skb->nfct = &ct->ct_general; |
| 801 | skb->nfctinfo = *ctinfo; |
| 802 | return ct; |
| 803 | } |
| 804 | |
| 805 | /* Netfilter hook itself. */ |
| 806 | unsigned int ip_conntrack_in(unsigned int hooknum, |
| 807 | struct sk_buff **pskb, |
| 808 | const struct net_device *in, |
| 809 | const struct net_device *out, |
| 810 | int (*okfn)(struct sk_buff *)) |
| 811 | { |
| 812 | struct ip_conntrack *ct; |
| 813 | enum ip_conntrack_info ctinfo; |
| 814 | struct ip_conntrack_protocol *proto; |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 815 | int set_reply = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | int ret; |
| 817 | |
| 818 | /* Previously seen (loopback or untracked)? Ignore. */ |
| 819 | if ((*pskb)->nfct) { |
| 820 | CONNTRACK_STAT_INC(ignore); |
| 821 | return NF_ACCEPT; |
| 822 | } |
| 823 | |
| 824 | /* Never happen */ |
| 825 | if ((*pskb)->nh.iph->frag_off & htons(IP_OFFSET)) { |
| 826 | if (net_ratelimit()) { |
| 827 | printk(KERN_ERR "ip_conntrack_in: Frag of proto %u (hook=%u)\n", |
| 828 | (*pskb)->nh.iph->protocol, hooknum); |
| 829 | } |
| 830 | return NF_DROP; |
| 831 | } |
| 832 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | /* Doesn't cover locally-generated broadcast, so not worth it. */ |
| 834 | #if 0 |
| 835 | /* Ignore broadcast: no `connection'. */ |
| 836 | if ((*pskb)->pkt_type == PACKET_BROADCAST) { |
| 837 | printk("Broadcast packet!\n"); |
| 838 | return NF_ACCEPT; |
| 839 | } else if (((*pskb)->nh.iph->daddr & htonl(0x000000FF)) |
| 840 | == htonl(0x000000FF)) { |
| 841 | printk("Should bcast: %u.%u.%u.%u->%u.%u.%u.%u (sk=%p, ptype=%u)\n", |
| 842 | NIPQUAD((*pskb)->nh.iph->saddr), |
| 843 | NIPQUAD((*pskb)->nh.iph->daddr), |
| 844 | (*pskb)->sk, (*pskb)->pkt_type); |
| 845 | } |
| 846 | #endif |
| 847 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 848 | proto = __ip_conntrack_proto_find((*pskb)->nh.iph->protocol); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 849 | |
| 850 | /* It may be an special packet, error, unclean... |
| 851 | * inverse of the return code tells to the netfilter |
| 852 | * core what to do with the packet. */ |
| 853 | if (proto->error != NULL |
| 854 | && (ret = proto->error(*pskb, &ctinfo, hooknum)) <= 0) { |
| 855 | CONNTRACK_STAT_INC(error); |
| 856 | CONNTRACK_STAT_INC(invalid); |
| 857 | return -ret; |
| 858 | } |
| 859 | |
| 860 | if (!(ct = resolve_normal_ct(*pskb, proto,&set_reply,hooknum,&ctinfo))) { |
| 861 | /* Not valid part of a connection */ |
| 862 | CONNTRACK_STAT_INC(invalid); |
| 863 | return NF_ACCEPT; |
| 864 | } |
| 865 | |
| 866 | if (IS_ERR(ct)) { |
| 867 | /* Too stressed to deal. */ |
| 868 | CONNTRACK_STAT_INC(drop); |
| 869 | return NF_DROP; |
| 870 | } |
| 871 | |
| 872 | IP_NF_ASSERT((*pskb)->nfct); |
| 873 | |
| 874 | ret = proto->packet(ct, *pskb, ctinfo); |
| 875 | if (ret < 0) { |
| 876 | /* Invalid: inverse of the return code tells |
| 877 | * the netfilter core what to do*/ |
| 878 | nf_conntrack_put((*pskb)->nfct); |
| 879 | (*pskb)->nfct = NULL; |
| 880 | CONNTRACK_STAT_INC(invalid); |
| 881 | return -ret; |
| 882 | } |
| 883 | |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 884 | if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status)) |
| 885 | ip_conntrack_event_cache(IPCT_STATUS, *pskb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 886 | |
| 887 | return ret; |
| 888 | } |
| 889 | |
| 890 | int invert_tuplepr(struct ip_conntrack_tuple *inverse, |
| 891 | const struct ip_conntrack_tuple *orig) |
| 892 | { |
| 893 | return ip_ct_invert_tuple(inverse, orig, |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 894 | __ip_conntrack_proto_find(orig->dst.protonum)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | } |
| 896 | |
| 897 | /* Would two expected things clash? */ |
| 898 | static inline int expect_clash(const struct ip_conntrack_expect *a, |
| 899 | const struct ip_conntrack_expect *b) |
| 900 | { |
| 901 | /* Part covered by intersection of masks must be unequal, |
| 902 | otherwise they clash */ |
| 903 | struct ip_conntrack_tuple intersect_mask |
| 904 | = { { a->mask.src.ip & b->mask.src.ip, |
| 905 | { a->mask.src.u.all & b->mask.src.u.all } }, |
| 906 | { a->mask.dst.ip & b->mask.dst.ip, |
| 907 | { a->mask.dst.u.all & b->mask.dst.u.all }, |
| 908 | a->mask.dst.protonum & b->mask.dst.protonum } }; |
| 909 | |
| 910 | return ip_ct_tuple_mask_cmp(&a->tuple, &b->tuple, &intersect_mask); |
| 911 | } |
| 912 | |
| 913 | static inline int expect_matches(const struct ip_conntrack_expect *a, |
| 914 | const struct ip_conntrack_expect *b) |
| 915 | { |
| 916 | return a->master == b->master |
| 917 | && ip_ct_tuple_equal(&a->tuple, &b->tuple) |
| 918 | && ip_ct_tuple_equal(&a->mask, &b->mask); |
| 919 | } |
| 920 | |
| 921 | /* Generally a bad idea to call this: could have matched already. */ |
| 922 | void ip_conntrack_unexpect_related(struct ip_conntrack_expect *exp) |
| 923 | { |
| 924 | struct ip_conntrack_expect *i; |
| 925 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 926 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 927 | /* choose the the oldest expectation to evict */ |
| 928 | list_for_each_entry_reverse(i, &ip_conntrack_expect_list, list) { |
| 929 | if (expect_matches(i, exp) && del_timer(&i->timeout)) { |
Pablo Neira Ayuso | 49719eb | 2005-09-06 15:10:46 -0700 | [diff] [blame] | 930 | ip_ct_unlink_expect(i); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 931 | write_unlock_bh(&ip_conntrack_lock); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 932 | ip_conntrack_expect_put(i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 933 | return; |
| 934 | } |
| 935 | } |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 936 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 937 | } |
| 938 | |
Pablo Neira Ayuso | 91c46e2 | 2005-09-06 15:10:23 -0700 | [diff] [blame] | 939 | /* We don't increase the master conntrack refcount for non-fulfilled |
| 940 | * conntracks. During the conntrack destruction, the expectations are |
| 941 | * always killed before the conntrack itself */ |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 942 | struct ip_conntrack_expect *ip_conntrack_expect_alloc(struct ip_conntrack *me) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 943 | { |
| 944 | struct ip_conntrack_expect *new; |
| 945 | |
| 946 | new = kmem_cache_alloc(ip_conntrack_expect_cachep, GFP_ATOMIC); |
| 947 | if (!new) { |
| 948 | DEBUGP("expect_related: OOM allocating expect\n"); |
| 949 | return NULL; |
| 950 | } |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 951 | new->master = me; |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 952 | atomic_set(&new->use, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 953 | return new; |
| 954 | } |
| 955 | |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 956 | void ip_conntrack_expect_put(struct ip_conntrack_expect *exp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 957 | { |
Pablo Neira Ayuso | 91c46e2 | 2005-09-06 15:10:23 -0700 | [diff] [blame] | 958 | if (atomic_dec_and_test(&exp->use)) |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 959 | kmem_cache_free(ip_conntrack_expect_cachep, exp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 960 | } |
| 961 | |
| 962 | static void ip_conntrack_expect_insert(struct ip_conntrack_expect *exp) |
| 963 | { |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 964 | atomic_inc(&exp->use); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 965 | exp->master->expecting++; |
| 966 | list_add(&exp->list, &ip_conntrack_expect_list); |
| 967 | |
Phil Oester | 1d3cdb4 | 2005-06-21 14:02:42 -0700 | [diff] [blame] | 968 | init_timer(&exp->timeout); |
| 969 | exp->timeout.data = (unsigned long)exp; |
| 970 | exp->timeout.function = expectation_timed_out; |
| 971 | exp->timeout.expires = jiffies + exp->master->helper->timeout * HZ; |
| 972 | add_timer(&exp->timeout); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 973 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 974 | exp->id = ++ip_conntrack_expect_next_id; |
| 975 | atomic_inc(&exp->use); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | CONNTRACK_STAT_INC(expect_create); |
| 977 | } |
| 978 | |
| 979 | /* Race with expectations being used means we could have none to find; OK. */ |
| 980 | static void evict_oldest_expect(struct ip_conntrack *master) |
| 981 | { |
| 982 | struct ip_conntrack_expect *i; |
| 983 | |
| 984 | list_for_each_entry_reverse(i, &ip_conntrack_expect_list, list) { |
| 985 | if (i->master == master) { |
| 986 | if (del_timer(&i->timeout)) { |
Pablo Neira Ayuso | 49719eb | 2005-09-06 15:10:46 -0700 | [diff] [blame] | 987 | ip_ct_unlink_expect(i); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 988 | ip_conntrack_expect_put(i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 989 | } |
| 990 | break; |
| 991 | } |
| 992 | } |
| 993 | } |
| 994 | |
| 995 | static inline int refresh_timer(struct ip_conntrack_expect *i) |
| 996 | { |
| 997 | if (!del_timer(&i->timeout)) |
| 998 | return 0; |
| 999 | |
| 1000 | i->timeout.expires = jiffies + i->master->helper->timeout*HZ; |
| 1001 | add_timer(&i->timeout); |
| 1002 | return 1; |
| 1003 | } |
| 1004 | |
| 1005 | int ip_conntrack_expect_related(struct ip_conntrack_expect *expect) |
| 1006 | { |
| 1007 | struct ip_conntrack_expect *i; |
| 1008 | int ret; |
| 1009 | |
| 1010 | DEBUGP("ip_conntrack_expect_related %p\n", related_to); |
| 1011 | DEBUGP("tuple: "); DUMP_TUPLE(&expect->tuple); |
| 1012 | DEBUGP("mask: "); DUMP_TUPLE(&expect->mask); |
| 1013 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1014 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1015 | list_for_each_entry(i, &ip_conntrack_expect_list, list) { |
| 1016 | if (expect_matches(i, expect)) { |
| 1017 | /* Refresh timer: if it's dying, ignore.. */ |
| 1018 | if (refresh_timer(i)) { |
| 1019 | ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1020 | goto out; |
| 1021 | } |
| 1022 | } else if (expect_clash(i, expect)) { |
| 1023 | ret = -EBUSY; |
| 1024 | goto out; |
| 1025 | } |
| 1026 | } |
| 1027 | |
| 1028 | /* Will be over limit? */ |
| 1029 | if (expect->master->helper->max_expected && |
| 1030 | expect->master->expecting >= expect->master->helper->max_expected) |
| 1031 | evict_oldest_expect(expect->master); |
| 1032 | |
| 1033 | ip_conntrack_expect_insert(expect); |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 1034 | ip_conntrack_expect_event(IPEXP_NEW, expect); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1035 | ret = 0; |
| 1036 | out: |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1037 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | return ret; |
| 1039 | } |
| 1040 | |
| 1041 | /* Alter reply tuple (maybe alter helper). This is for NAT, and is |
| 1042 | implicitly racy: see __ip_conntrack_confirm */ |
| 1043 | void ip_conntrack_alter_reply(struct ip_conntrack *conntrack, |
| 1044 | const struct ip_conntrack_tuple *newreply) |
| 1045 | { |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1046 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1047 | /* Should be unconfirmed, so not in hash table yet */ |
| 1048 | IP_NF_ASSERT(!is_confirmed(conntrack)); |
| 1049 | |
| 1050 | DEBUGP("Altering reply tuple of %p to ", conntrack); |
| 1051 | DUMP_TUPLE(newreply); |
| 1052 | |
| 1053 | conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply; |
| 1054 | if (!conntrack->master && conntrack->expecting == 0) |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 1055 | conntrack->helper = __ip_conntrack_helper_find(newreply); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1056 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1057 | } |
| 1058 | |
| 1059 | int ip_conntrack_helper_register(struct ip_conntrack_helper *me) |
| 1060 | { |
| 1061 | BUG_ON(me->timeout == 0); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1062 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1063 | list_prepend(&helpers, me); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1064 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1065 | |
| 1066 | return 0; |
| 1067 | } |
| 1068 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 1069 | struct ip_conntrack_helper * |
| 1070 | __ip_conntrack_helper_find_byname(const char *name) |
| 1071 | { |
| 1072 | struct ip_conntrack_helper *h; |
| 1073 | |
| 1074 | list_for_each_entry(h, &helpers, list) { |
| 1075 | if (!strcmp(h->name, name)) |
| 1076 | return h; |
| 1077 | } |
| 1078 | |
| 1079 | return NULL; |
| 1080 | } |
| 1081 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1082 | static inline int unhelp(struct ip_conntrack_tuple_hash *i, |
| 1083 | const struct ip_conntrack_helper *me) |
| 1084 | { |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 1085 | if (tuplehash_to_ctrack(i)->helper == me) { |
| 1086 | ip_conntrack_event(IPCT_HELPER, tuplehash_to_ctrack(i)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1087 | tuplehash_to_ctrack(i)->helper = NULL; |
Harald Welte | ac3247b | 2005-08-09 19:28:03 -0700 | [diff] [blame] | 1088 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1089 | return 0; |
| 1090 | } |
| 1091 | |
| 1092 | void ip_conntrack_helper_unregister(struct ip_conntrack_helper *me) |
| 1093 | { |
| 1094 | unsigned int i; |
| 1095 | struct ip_conntrack_expect *exp, *tmp; |
| 1096 | |
| 1097 | /* Need write lock here, to delete helper. */ |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1098 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1099 | LIST_DELETE(&helpers, me); |
| 1100 | |
| 1101 | /* Get rid of expectations */ |
| 1102 | list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list, list) { |
| 1103 | if (exp->master->helper == me && del_timer(&exp->timeout)) { |
Pablo Neira Ayuso | 49719eb | 2005-09-06 15:10:46 -0700 | [diff] [blame] | 1104 | ip_ct_unlink_expect(exp); |
Rusty Russell | 4acdbdb | 2005-07-21 13:14:46 -0700 | [diff] [blame] | 1105 | ip_conntrack_expect_put(exp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1106 | } |
| 1107 | } |
| 1108 | /* Get rid of expecteds, set helpers to NULL. */ |
| 1109 | LIST_FIND_W(&unconfirmed, unhelp, struct ip_conntrack_tuple_hash*, me); |
| 1110 | for (i = 0; i < ip_conntrack_htable_size; i++) |
| 1111 | LIST_FIND_W(&ip_conntrack_hash[i], unhelp, |
| 1112 | struct ip_conntrack_tuple_hash *, me); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1113 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1114 | |
| 1115 | /* Someone could be still looking at the helper in a bh. */ |
| 1116 | synchronize_net(); |
| 1117 | } |
| 1118 | |
Harald Welte | 1dfbab5 | 2005-09-22 23:46:57 -0700 | [diff] [blame] | 1119 | /* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */ |
| 1120 | void __ip_ct_refresh_acct(struct ip_conntrack *ct, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1121 | enum ip_conntrack_info ctinfo, |
| 1122 | const struct sk_buff *skb, |
Harald Welte | 1dfbab5 | 2005-09-22 23:46:57 -0700 | [diff] [blame] | 1123 | unsigned long extra_jiffies, |
| 1124 | int do_acct) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1125 | { |
Harald Welte | a051a8f | 2005-10-10 21:21:10 -0700 | [diff] [blame] | 1126 | int event = 0; |
Harald Welte | 1dfbab5 | 2005-09-22 23:46:57 -0700 | [diff] [blame] | 1127 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | IP_NF_ASSERT(ct->timeout.data == (unsigned long)ct); |
Harald Welte | 1dfbab5 | 2005-09-22 23:46:57 -0700 | [diff] [blame] | 1129 | IP_NF_ASSERT(skb); |
| 1130 | |
| 1131 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1132 | |
| 1133 | /* If not in hash table, timer will not be active yet */ |
| 1134 | if (!is_confirmed(ct)) { |
| 1135 | ct->timeout.expires = extra_jiffies; |
Harald Welte | a051a8f | 2005-10-10 21:21:10 -0700 | [diff] [blame] | 1136 | event = IPCT_REFRESH; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1137 | } else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1138 | /* Need del_timer for race avoidance (may already be dying). */ |
| 1139 | if (del_timer(&ct->timeout)) { |
| 1140 | ct->timeout.expires = jiffies + extra_jiffies; |
| 1141 | add_timer(&ct->timeout); |
Harald Welte | a051a8f | 2005-10-10 21:21:10 -0700 | [diff] [blame] | 1142 | event = IPCT_REFRESH; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1143 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1144 | } |
Harald Welte | 1dfbab5 | 2005-09-22 23:46:57 -0700 | [diff] [blame] | 1145 | |
| 1146 | #ifdef CONFIG_IP_NF_CT_ACCT |
| 1147 | if (do_acct) { |
| 1148 | ct->counters[CTINFO2DIR(ctinfo)].packets++; |
| 1149 | ct->counters[CTINFO2DIR(ctinfo)].bytes += |
| 1150 | ntohs(skb->nh.iph->tot_len); |
Harald Welte | a051a8f | 2005-10-10 21:21:10 -0700 | [diff] [blame] | 1151 | if ((ct->counters[CTINFO2DIR(ctinfo)].packets & 0x80000000) |
| 1152 | || (ct->counters[CTINFO2DIR(ctinfo)].bytes & 0x80000000)) |
| 1153 | event |= IPCT_COUNTER_FILLING; |
Harald Welte | 1dfbab5 | 2005-09-22 23:46:57 -0700 | [diff] [blame] | 1154 | } |
| 1155 | #endif |
| 1156 | |
| 1157 | write_unlock_bh(&ip_conntrack_lock); |
| 1158 | |
| 1159 | /* must be unlocked when calling event cache */ |
Harald Welte | a051a8f | 2005-10-10 21:21:10 -0700 | [diff] [blame] | 1160 | if (event) |
| 1161 | ip_conntrack_event_cache(event, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1162 | } |
| 1163 | |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 1164 | #if defined(CONFIG_IP_NF_CONNTRACK_NETLINK) || \ |
| 1165 | defined(CONFIG_IP_NF_CONNTRACK_NETLINK_MODULE) |
| 1166 | /* Generic function for tcp/udp/sctp/dccp and alike. This needs to be |
| 1167 | * in ip_conntrack_core, since we don't want the protocols to autoload |
| 1168 | * or depend on ctnetlink */ |
| 1169 | int ip_ct_port_tuple_to_nfattr(struct sk_buff *skb, |
| 1170 | const struct ip_conntrack_tuple *tuple) |
| 1171 | { |
| 1172 | NFA_PUT(skb, CTA_PROTO_SRC_PORT, sizeof(u_int16_t), |
| 1173 | &tuple->src.u.tcp.port); |
| 1174 | NFA_PUT(skb, CTA_PROTO_DST_PORT, sizeof(u_int16_t), |
| 1175 | &tuple->dst.u.tcp.port); |
| 1176 | return 0; |
| 1177 | |
| 1178 | nfattr_failure: |
| 1179 | return -1; |
| 1180 | } |
| 1181 | |
| 1182 | int ip_ct_port_nfattr_to_tuple(struct nfattr *tb[], |
| 1183 | struct ip_conntrack_tuple *t) |
| 1184 | { |
| 1185 | if (!tb[CTA_PROTO_SRC_PORT-1] || !tb[CTA_PROTO_DST_PORT-1]) |
| 1186 | return -EINVAL; |
| 1187 | |
| 1188 | t->src.u.tcp.port = |
| 1189 | *(u_int16_t *)NFA_DATA(tb[CTA_PROTO_SRC_PORT-1]); |
| 1190 | t->dst.u.tcp.port = |
| 1191 | *(u_int16_t *)NFA_DATA(tb[CTA_PROTO_DST_PORT-1]); |
| 1192 | |
| 1193 | return 0; |
| 1194 | } |
| 1195 | #endif |
| 1196 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1197 | /* Returns new sk_buff, or NULL */ |
| 1198 | struct sk_buff * |
| 1199 | ip_ct_gather_frags(struct sk_buff *skb, u_int32_t user) |
| 1200 | { |
David S. Miller | 8be5893 | 2005-05-19 12:36:33 -0700 | [diff] [blame] | 1201 | skb_orphan(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1202 | |
| 1203 | local_bh_disable(); |
| 1204 | skb = ip_defrag(skb, user); |
| 1205 | local_bh_enable(); |
| 1206 | |
Harald Welte | 6869c4d | 2005-08-09 19:24:19 -0700 | [diff] [blame] | 1207 | if (skb) |
David S. Miller | 8be5893 | 2005-05-19 12:36:33 -0700 | [diff] [blame] | 1208 | ip_send_check(skb->nh.iph); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1209 | return skb; |
| 1210 | } |
| 1211 | |
| 1212 | /* Used by ipt_REJECT. */ |
| 1213 | static void ip_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb) |
| 1214 | { |
| 1215 | struct ip_conntrack *ct; |
| 1216 | enum ip_conntrack_info ctinfo; |
| 1217 | |
| 1218 | /* This ICMP is in reverse direction to the packet which caused it */ |
| 1219 | ct = ip_conntrack_get(skb, &ctinfo); |
| 1220 | |
| 1221 | if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) |
| 1222 | ctinfo = IP_CT_RELATED + IP_CT_IS_REPLY; |
| 1223 | else |
| 1224 | ctinfo = IP_CT_RELATED; |
| 1225 | |
| 1226 | /* Attach to new skbuff, and increment count */ |
| 1227 | nskb->nfct = &ct->ct_general; |
| 1228 | nskb->nfctinfo = ctinfo; |
| 1229 | nf_conntrack_get(nskb->nfct); |
| 1230 | } |
| 1231 | |
| 1232 | static inline int |
| 1233 | do_iter(const struct ip_conntrack_tuple_hash *i, |
| 1234 | int (*iter)(struct ip_conntrack *i, void *data), |
| 1235 | void *data) |
| 1236 | { |
| 1237 | return iter(tuplehash_to_ctrack(i), data); |
| 1238 | } |
| 1239 | |
| 1240 | /* Bring out ya dead! */ |
| 1241 | static struct ip_conntrack_tuple_hash * |
| 1242 | get_next_corpse(int (*iter)(struct ip_conntrack *i, void *data), |
| 1243 | void *data, unsigned int *bucket) |
| 1244 | { |
| 1245 | struct ip_conntrack_tuple_hash *h = NULL; |
| 1246 | |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1247 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1248 | for (; *bucket < ip_conntrack_htable_size; (*bucket)++) { |
| 1249 | h = LIST_FIND_W(&ip_conntrack_hash[*bucket], do_iter, |
| 1250 | struct ip_conntrack_tuple_hash *, iter, data); |
| 1251 | if (h) |
| 1252 | break; |
| 1253 | } |
| 1254 | if (!h) |
| 1255 | h = LIST_FIND_W(&unconfirmed, do_iter, |
| 1256 | struct ip_conntrack_tuple_hash *, iter, data); |
| 1257 | if (h) |
| 1258 | atomic_inc(&tuplehash_to_ctrack(h)->ct_general.use); |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1259 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1260 | |
| 1261 | return h; |
| 1262 | } |
| 1263 | |
| 1264 | void |
| 1265 | ip_ct_iterate_cleanup(int (*iter)(struct ip_conntrack *i, void *), void *data) |
| 1266 | { |
| 1267 | struct ip_conntrack_tuple_hash *h; |
| 1268 | unsigned int bucket = 0; |
| 1269 | |
| 1270 | while ((h = get_next_corpse(iter, data, &bucket)) != NULL) { |
| 1271 | struct ip_conntrack *ct = tuplehash_to_ctrack(h); |
| 1272 | /* Time to push up daises... */ |
| 1273 | if (del_timer(&ct->timeout)) |
| 1274 | death_by_timeout((unsigned long)ct); |
| 1275 | /* ... else the timer will get him soon. */ |
| 1276 | |
| 1277 | ip_conntrack_put(ct); |
| 1278 | } |
| 1279 | } |
| 1280 | |
| 1281 | /* Fast function for those who don't want to parse /proc (and I don't |
| 1282 | blame them). */ |
| 1283 | /* Reversing the socket's dst/src point of view gives us the reply |
| 1284 | mapping. */ |
| 1285 | static int |
| 1286 | getorigdst(struct sock *sk, int optval, void __user *user, int *len) |
| 1287 | { |
| 1288 | struct inet_sock *inet = inet_sk(sk); |
| 1289 | struct ip_conntrack_tuple_hash *h; |
| 1290 | struct ip_conntrack_tuple tuple; |
| 1291 | |
| 1292 | IP_CT_TUPLE_U_BLANK(&tuple); |
| 1293 | tuple.src.ip = inet->rcv_saddr; |
| 1294 | tuple.src.u.tcp.port = inet->sport; |
| 1295 | tuple.dst.ip = inet->daddr; |
| 1296 | tuple.dst.u.tcp.port = inet->dport; |
| 1297 | tuple.dst.protonum = IPPROTO_TCP; |
| 1298 | |
| 1299 | /* We only do TCP at the moment: is there a better way? */ |
| 1300 | if (strcmp(sk->sk_prot->name, "TCP")) { |
| 1301 | DEBUGP("SO_ORIGINAL_DST: Not a TCP socket\n"); |
| 1302 | return -ENOPROTOOPT; |
| 1303 | } |
| 1304 | |
| 1305 | if ((unsigned int) *len < sizeof(struct sockaddr_in)) { |
| 1306 | DEBUGP("SO_ORIGINAL_DST: len %u not %u\n", |
| 1307 | *len, sizeof(struct sockaddr_in)); |
| 1308 | return -EINVAL; |
| 1309 | } |
| 1310 | |
| 1311 | h = ip_conntrack_find_get(&tuple, NULL); |
| 1312 | if (h) { |
| 1313 | struct sockaddr_in sin; |
| 1314 | struct ip_conntrack *ct = tuplehash_to_ctrack(h); |
| 1315 | |
| 1316 | sin.sin_family = AF_INET; |
| 1317 | sin.sin_port = ct->tuplehash[IP_CT_DIR_ORIGINAL] |
| 1318 | .tuple.dst.u.tcp.port; |
| 1319 | sin.sin_addr.s_addr = ct->tuplehash[IP_CT_DIR_ORIGINAL] |
| 1320 | .tuple.dst.ip; |
| 1321 | |
| 1322 | DEBUGP("SO_ORIGINAL_DST: %u.%u.%u.%u %u\n", |
| 1323 | NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port)); |
| 1324 | ip_conntrack_put(ct); |
| 1325 | if (copy_to_user(user, &sin, sizeof(sin)) != 0) |
| 1326 | return -EFAULT; |
| 1327 | else |
| 1328 | return 0; |
| 1329 | } |
| 1330 | DEBUGP("SO_ORIGINAL_DST: Can't find %u.%u.%u.%u/%u-%u.%u.%u.%u/%u.\n", |
| 1331 | NIPQUAD(tuple.src.ip), ntohs(tuple.src.u.tcp.port), |
| 1332 | NIPQUAD(tuple.dst.ip), ntohs(tuple.dst.u.tcp.port)); |
| 1333 | return -ENOENT; |
| 1334 | } |
| 1335 | |
| 1336 | static struct nf_sockopt_ops so_getorigdst = { |
| 1337 | .pf = PF_INET, |
| 1338 | .get_optmin = SO_ORIGINAL_DST, |
| 1339 | .get_optmax = SO_ORIGINAL_DST+1, |
| 1340 | .get = &getorigdst, |
| 1341 | }; |
| 1342 | |
| 1343 | static int kill_all(struct ip_conntrack *i, void *data) |
| 1344 | { |
| 1345 | return 1; |
| 1346 | } |
| 1347 | |
Patrick McHardy | afe5c6b | 2005-12-05 13:33:50 -0800 | [diff] [blame] | 1348 | void ip_conntrack_flush(void) |
| 1349 | { |
| 1350 | ip_ct_iterate_cleanup(kill_all, NULL); |
| 1351 | } |
| 1352 | |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1353 | static void free_conntrack_hash(struct list_head *hash, int vmalloced,int size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1354 | { |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1355 | if (vmalloced) |
| 1356 | vfree(hash); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1357 | else |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1358 | free_pages((unsigned long)hash, |
| 1359 | get_order(sizeof(struct list_head) * size)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1360 | } |
| 1361 | |
Patrick McHardy | afe5c6b | 2005-12-05 13:33:50 -0800 | [diff] [blame] | 1362 | /* Mishearing the voices in his head, our hero wonders how he's |
| 1363 | supposed to kill the mall. */ |
| 1364 | void ip_conntrack_cleanup(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1365 | { |
Patrick McHardy | afe5c6b | 2005-12-05 13:33:50 -0800 | [diff] [blame] | 1366 | ip_ct_attach = NULL; |
| 1367 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1368 | /* This makes sure all current packets have passed through |
| 1369 | netfilter framework. Roll on, two-stage module |
| 1370 | delete... */ |
| 1371 | synchronize_net(); |
Harald Welte | 080774a | 2005-08-09 19:32:58 -0700 | [diff] [blame] | 1372 | |
Patrick McHardy | a86888b | 2005-08-09 20:02:13 -0700 | [diff] [blame] | 1373 | ip_ct_event_cache_flush(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1374 | i_see_dead_people: |
Patrick McHardy | afe5c6b | 2005-12-05 13:33:50 -0800 | [diff] [blame] | 1375 | ip_conntrack_flush(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1376 | if (atomic_read(&ip_conntrack_count) != 0) { |
| 1377 | schedule(); |
| 1378 | goto i_see_dead_people; |
| 1379 | } |
Patrick McHardy | 21f930e | 2005-07-22 12:51:03 -0700 | [diff] [blame] | 1380 | /* wait until all references to ip_conntrack_untracked are dropped */ |
| 1381 | while (atomic_read(&ip_conntrack_untracked.ct_general.use) > 1) |
| 1382 | schedule(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1383 | |
| 1384 | kmem_cache_destroy(ip_conntrack_cachep); |
| 1385 | kmem_cache_destroy(ip_conntrack_expect_cachep); |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1386 | free_conntrack_hash(ip_conntrack_hash, ip_conntrack_vmalloc, |
| 1387 | ip_conntrack_htable_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1388 | nf_unregister_sockopt(&so_getorigdst); |
| 1389 | } |
| 1390 | |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1391 | static struct list_head *alloc_hashtable(int size, int *vmalloced) |
| 1392 | { |
| 1393 | struct list_head *hash; |
| 1394 | unsigned int i; |
| 1395 | |
| 1396 | *vmalloced = 0; |
| 1397 | hash = (void*)__get_free_pages(GFP_KERNEL, |
| 1398 | get_order(sizeof(struct list_head) |
| 1399 | * size)); |
| 1400 | if (!hash) { |
| 1401 | *vmalloced = 1; |
| 1402 | printk(KERN_WARNING"ip_conntrack: falling back to vmalloc.\n"); |
| 1403 | hash = vmalloc(sizeof(struct list_head) * size); |
| 1404 | } |
| 1405 | |
| 1406 | if (hash) |
| 1407 | for (i = 0; i < size; i++) |
| 1408 | INIT_LIST_HEAD(&hash[i]); |
| 1409 | |
| 1410 | return hash; |
| 1411 | } |
| 1412 | |
Adrian Bunk | d127e94 | 2005-11-29 16:28:18 -0800 | [diff] [blame] | 1413 | static int set_hashsize(const char *val, struct kernel_param *kp) |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1414 | { |
| 1415 | int i, bucket, hashsize, vmalloced; |
| 1416 | int old_vmalloced, old_size; |
| 1417 | int rnd; |
| 1418 | struct list_head *hash, *old_hash; |
| 1419 | struct ip_conntrack_tuple_hash *h; |
| 1420 | |
| 1421 | /* On boot, we can set this without any fancy locking. */ |
| 1422 | if (!ip_conntrack_htable_size) |
| 1423 | return param_set_int(val, kp); |
| 1424 | |
| 1425 | hashsize = simple_strtol(val, NULL, 0); |
| 1426 | if (!hashsize) |
| 1427 | return -EINVAL; |
| 1428 | |
| 1429 | hash = alloc_hashtable(hashsize, &vmalloced); |
| 1430 | if (!hash) |
| 1431 | return -ENOMEM; |
| 1432 | |
| 1433 | /* We have to rehash for the new table anyway, so we also can |
| 1434 | * use a new random seed */ |
| 1435 | get_random_bytes(&rnd, 4); |
| 1436 | |
| 1437 | write_lock_bh(&ip_conntrack_lock); |
| 1438 | for (i = 0; i < ip_conntrack_htable_size; i++) { |
| 1439 | while (!list_empty(&ip_conntrack_hash[i])) { |
| 1440 | h = list_entry(ip_conntrack_hash[i].next, |
| 1441 | struct ip_conntrack_tuple_hash, list); |
| 1442 | list_del(&h->list); |
| 1443 | bucket = __hash_conntrack(&h->tuple, hashsize, rnd); |
| 1444 | list_add_tail(&h->list, &hash[bucket]); |
| 1445 | } |
| 1446 | } |
| 1447 | old_size = ip_conntrack_htable_size; |
| 1448 | old_vmalloced = ip_conntrack_vmalloc; |
| 1449 | old_hash = ip_conntrack_hash; |
| 1450 | |
| 1451 | ip_conntrack_htable_size = hashsize; |
| 1452 | ip_conntrack_vmalloc = vmalloced; |
| 1453 | ip_conntrack_hash = hash; |
| 1454 | ip_conntrack_hash_rnd = rnd; |
| 1455 | write_unlock_bh(&ip_conntrack_lock); |
| 1456 | |
| 1457 | free_conntrack_hash(old_hash, old_vmalloced, old_size); |
| 1458 | return 0; |
| 1459 | } |
| 1460 | |
| 1461 | module_param_call(hashsize, set_hashsize, param_get_uint, |
| 1462 | &ip_conntrack_htable_size, 0600); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1463 | |
| 1464 | int __init ip_conntrack_init(void) |
| 1465 | { |
| 1466 | unsigned int i; |
| 1467 | int ret; |
| 1468 | |
| 1469 | /* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB |
| 1470 | * machine has 256 buckets. >= 1GB machines have 8192 buckets. */ |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1471 | if (!ip_conntrack_htable_size) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1472 | ip_conntrack_htable_size |
| 1473 | = (((num_physpages << PAGE_SHIFT) / 16384) |
| 1474 | / sizeof(struct list_head)); |
| 1475 | if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE)) |
| 1476 | ip_conntrack_htable_size = 8192; |
| 1477 | if (ip_conntrack_htable_size < 16) |
| 1478 | ip_conntrack_htable_size = 16; |
| 1479 | } |
| 1480 | ip_conntrack_max = 8 * ip_conntrack_htable_size; |
| 1481 | |
| 1482 | printk("ip_conntrack version %s (%u buckets, %d max)" |
| 1483 | " - %Zd bytes per conntrack\n", IP_CONNTRACK_VERSION, |
| 1484 | ip_conntrack_htable_size, ip_conntrack_max, |
| 1485 | sizeof(struct ip_conntrack)); |
| 1486 | |
| 1487 | ret = nf_register_sockopt(&so_getorigdst); |
| 1488 | if (ret != 0) { |
| 1489 | printk(KERN_ERR "Unable to register netfilter socket option\n"); |
| 1490 | return ret; |
| 1491 | } |
| 1492 | |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1493 | ip_conntrack_hash = alloc_hashtable(ip_conntrack_htable_size, |
| 1494 | &ip_conntrack_vmalloc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1495 | if (!ip_conntrack_hash) { |
| 1496 | printk(KERN_ERR "Unable to create ip_conntrack_hash\n"); |
| 1497 | goto err_unreg_sockopt; |
| 1498 | } |
| 1499 | |
| 1500 | ip_conntrack_cachep = kmem_cache_create("ip_conntrack", |
| 1501 | sizeof(struct ip_conntrack), 0, |
| 1502 | 0, NULL, NULL); |
| 1503 | if (!ip_conntrack_cachep) { |
| 1504 | printk(KERN_ERR "Unable to create ip_conntrack slab cache\n"); |
| 1505 | goto err_free_hash; |
| 1506 | } |
| 1507 | |
| 1508 | ip_conntrack_expect_cachep = kmem_cache_create("ip_conntrack_expect", |
| 1509 | sizeof(struct ip_conntrack_expect), |
| 1510 | 0, 0, NULL, NULL); |
| 1511 | if (!ip_conntrack_expect_cachep) { |
| 1512 | printk(KERN_ERR "Unable to create ip_expect slab cache\n"); |
| 1513 | goto err_free_conntrack_slab; |
| 1514 | } |
| 1515 | |
| 1516 | /* Don't NEED lock here, but good form anyway. */ |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1517 | write_lock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1518 | for (i = 0; i < MAX_IP_CT_PROTO; i++) |
| 1519 | ip_ct_protos[i] = &ip_conntrack_generic_protocol; |
| 1520 | /* Sew in builtin protocols. */ |
| 1521 | ip_ct_protos[IPPROTO_TCP] = &ip_conntrack_protocol_tcp; |
| 1522 | ip_ct_protos[IPPROTO_UDP] = &ip_conntrack_protocol_udp; |
| 1523 | ip_ct_protos[IPPROTO_ICMP] = &ip_conntrack_protocol_icmp; |
Patrick McHardy | e45b1be | 2005-06-21 14:01:30 -0700 | [diff] [blame] | 1524 | write_unlock_bh(&ip_conntrack_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1525 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1526 | /* For use by ipt_REJECT */ |
| 1527 | ip_ct_attach = ip_conntrack_attach; |
| 1528 | |
| 1529 | /* Set up fake conntrack: |
| 1530 | - to never be deleted, not in any hashes */ |
| 1531 | atomic_set(&ip_conntrack_untracked.ct_general.use, 1); |
| 1532 | /* - and look it like as a confirmed connection */ |
| 1533 | set_bit(IPS_CONFIRMED_BIT, &ip_conntrack_untracked.status); |
| 1534 | |
| 1535 | return ret; |
| 1536 | |
| 1537 | err_free_conntrack_slab: |
| 1538 | kmem_cache_destroy(ip_conntrack_cachep); |
| 1539 | err_free_hash: |
Harald Welte | eed75f1 | 2005-10-16 14:22:59 +0200 | [diff] [blame] | 1540 | free_conntrack_hash(ip_conntrack_hash, ip_conntrack_vmalloc, |
| 1541 | ip_conntrack_htable_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1542 | err_unreg_sockopt: |
| 1543 | nf_unregister_sockopt(&so_getorigdst); |
| 1544 | |
| 1545 | return -ENOMEM; |
| 1546 | } |