Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [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 |
Harald Welte | dc808fe | 2006-03-20 17:56:32 -0800 | [diff] [blame] | 6 | * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 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. |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 12 | */ |
| 13 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 14 | #include <linux/types.h> |
| 15 | #include <linux/netfilter.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/skbuff.h> |
| 18 | #include <linux/proc_fs.h> |
| 19 | #include <linux/vmalloc.h> |
| 20 | #include <linux/stddef.h> |
| 21 | #include <linux/slab.h> |
| 22 | #include <linux/random.h> |
| 23 | #include <linux/jhash.h> |
| 24 | #include <linux/err.h> |
| 25 | #include <linux/percpu.h> |
| 26 | #include <linux/moduleparam.h> |
| 27 | #include <linux/notifier.h> |
| 28 | #include <linux/kernel.h> |
| 29 | #include <linux/netdevice.h> |
| 30 | #include <linux/socket.h> |
Al Viro | d7fe0f2 | 2006-12-03 23:15:30 -0500 | [diff] [blame] | 31 | #include <linux/mm.h> |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 32 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 33 | #include <net/netfilter/nf_conntrack.h> |
| 34 | #include <net/netfilter/nf_conntrack_l3proto.h> |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 35 | #include <net/netfilter/nf_conntrack_l4proto.h> |
Martin Josefsson | 77ab9cf | 2006-11-29 02:34:58 +0100 | [diff] [blame] | 36 | #include <net/netfilter/nf_conntrack_expect.h> |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 37 | #include <net/netfilter/nf_conntrack_helper.h> |
| 38 | #include <net/netfilter/nf_conntrack_core.h> |
Yasuyuki Kozakai | ecfab2c | 2007-07-07 22:23:21 -0700 | [diff] [blame] | 39 | #include <net/netfilter/nf_conntrack_extend.h> |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 40 | |
Harald Welte | dc808fe | 2006-03-20 17:56:32 -0800 | [diff] [blame] | 41 | #define NF_CONNTRACK_VERSION "0.5.0" |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 42 | |
| 43 | #if 0 |
| 44 | #define DEBUGP printk |
| 45 | #else |
| 46 | #define DEBUGP(format, args...) |
| 47 | #endif |
| 48 | |
| 49 | DEFINE_RWLOCK(nf_conntrack_lock); |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 50 | EXPORT_SYMBOL_GPL(nf_conntrack_lock); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 51 | |
| 52 | /* nf_conntrack_standalone needs this */ |
| 53 | atomic_t nf_conntrack_count = ATOMIC_INIT(0); |
Patrick McHardy | a999e68 | 2006-11-29 02:35:20 +0100 | [diff] [blame] | 54 | EXPORT_SYMBOL_GPL(nf_conntrack_count); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 55 | |
Martin Josefsson | e2b7606 | 2006-11-29 02:35:04 +0100 | [diff] [blame] | 56 | unsigned int nf_conntrack_htable_size __read_mostly; |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 57 | EXPORT_SYMBOL_GPL(nf_conntrack_htable_size); |
| 58 | |
Brian Haley | 94aec08 | 2006-09-18 00:05:22 -0700 | [diff] [blame] | 59 | int nf_conntrack_max __read_mostly; |
Patrick McHardy | a999e68 | 2006-11-29 02:35:20 +0100 | [diff] [blame] | 60 | EXPORT_SYMBOL_GPL(nf_conntrack_max); |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 61 | |
Brian Haley | 1192e40 | 2006-09-20 12:03:46 -0700 | [diff] [blame] | 62 | struct list_head *nf_conntrack_hash __read_mostly; |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 63 | EXPORT_SYMBOL_GPL(nf_conntrack_hash); |
| 64 | |
Martin Josefsson | e2b7606 | 2006-11-29 02:35:04 +0100 | [diff] [blame] | 65 | struct nf_conn nf_conntrack_untracked __read_mostly; |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 66 | EXPORT_SYMBOL_GPL(nf_conntrack_untracked); |
| 67 | |
Brian Haley | 94aec08 | 2006-09-18 00:05:22 -0700 | [diff] [blame] | 68 | unsigned int nf_ct_log_invalid __read_mostly; |
Martin Josefsson | 7e5d03b | 2006-11-29 02:34:59 +0100 | [diff] [blame] | 69 | LIST_HEAD(unconfirmed); |
Brian Haley | 1192e40 | 2006-09-20 12:03:46 -0700 | [diff] [blame] | 70 | static int nf_conntrack_vmalloc __read_mostly; |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 71 | static struct kmem_cache *nf_conntrack_cachep __read_mostly; |
Pablo Neira Ayuso | 4e3882f | 2006-03-22 13:55:11 -0800 | [diff] [blame] | 72 | static unsigned int nf_conntrack_next_id; |
Martin Josefsson | 77ab9cf | 2006-11-29 02:34:58 +0100 | [diff] [blame] | 73 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 74 | DEFINE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat); |
| 75 | EXPORT_PER_CPU_SYMBOL(nf_conntrack_stat); |
| 76 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 77 | static int nf_conntrack_hash_rnd_initted; |
| 78 | static unsigned int nf_conntrack_hash_rnd; |
| 79 | |
| 80 | static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple, |
| 81 | unsigned int size, unsigned int rnd) |
| 82 | { |
| 83 | unsigned int a, b; |
Sami Farin | 9b88790 | 2007-03-14 16:43:00 -0700 | [diff] [blame] | 84 | |
| 85 | a = jhash2(tuple->src.u3.all, ARRAY_SIZE(tuple->src.u3.all), |
| 86 | (tuple->src.l3num << 16) | tuple->dst.protonum); |
| 87 | b = jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all), |
| 88 | (tuple->src.u.all << 16) | tuple->dst.u.all); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 89 | |
| 90 | return jhash_2words(a, b, rnd) % size; |
| 91 | } |
| 92 | |
| 93 | static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple) |
| 94 | { |
| 95 | return __hash_conntrack(tuple, nf_conntrack_htable_size, |
| 96 | nf_conntrack_hash_rnd); |
| 97 | } |
| 98 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 99 | int |
| 100 | nf_ct_get_tuple(const struct sk_buff *skb, |
| 101 | unsigned int nhoff, |
| 102 | unsigned int dataoff, |
| 103 | u_int16_t l3num, |
| 104 | u_int8_t protonum, |
| 105 | struct nf_conntrack_tuple *tuple, |
| 106 | const struct nf_conntrack_l3proto *l3proto, |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 107 | const struct nf_conntrack_l4proto *l4proto) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 108 | { |
| 109 | NF_CT_TUPLE_U_BLANK(tuple); |
| 110 | |
| 111 | tuple->src.l3num = l3num; |
| 112 | if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0) |
| 113 | return 0; |
| 114 | |
| 115 | tuple->dst.protonum = protonum; |
| 116 | tuple->dst.dir = IP_CT_DIR_ORIGINAL; |
| 117 | |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 118 | return l4proto->pkt_to_tuple(skb, dataoff, tuple); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 119 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 120 | EXPORT_SYMBOL_GPL(nf_ct_get_tuple); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 121 | |
| 122 | int |
| 123 | nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse, |
| 124 | const struct nf_conntrack_tuple *orig, |
| 125 | const struct nf_conntrack_l3proto *l3proto, |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 126 | const struct nf_conntrack_l4proto *l4proto) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 127 | { |
| 128 | NF_CT_TUPLE_U_BLANK(inverse); |
| 129 | |
| 130 | inverse->src.l3num = orig->src.l3num; |
| 131 | if (l3proto->invert_tuple(inverse, orig) == 0) |
| 132 | return 0; |
| 133 | |
| 134 | inverse->dst.dir = !orig->dst.dir; |
| 135 | |
| 136 | inverse->dst.protonum = orig->dst.protonum; |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 137 | return l4proto->invert_tuple(inverse, orig); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 138 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 139 | EXPORT_SYMBOL_GPL(nf_ct_invert_tuple); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 140 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 141 | static void |
| 142 | clean_from_lists(struct nf_conn *ct) |
| 143 | { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 144 | DEBUGP("clean_from_lists(%p)\n", ct); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 145 | list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list); |
| 146 | list_del(&ct->tuplehash[IP_CT_DIR_REPLY].list); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 147 | |
| 148 | /* Destroy all pending expectations */ |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 149 | nf_ct_remove_expectations(ct); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 150 | } |
| 151 | |
| 152 | static void |
| 153 | destroy_conntrack(struct nf_conntrack *nfct) |
| 154 | { |
| 155 | struct nf_conn *ct = (struct nf_conn *)nfct; |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 156 | struct nf_conntrack_l4proto *l4proto; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 157 | |
| 158 | DEBUGP("destroy_conntrack(%p)\n", ct); |
| 159 | NF_CT_ASSERT(atomic_read(&nfct->use) == 0); |
| 160 | NF_CT_ASSERT(!timer_pending(&ct->timeout)); |
| 161 | |
| 162 | nf_conntrack_event(IPCT_DESTROY, ct); |
| 163 | set_bit(IPS_DYING_BIT, &ct->status); |
| 164 | |
| 165 | /* To make sure we don't get any weird locking issues here: |
| 166 | * destroy_conntrack() MUST NOT be called with a write lock |
| 167 | * to nf_conntrack_lock!!! -HW */ |
Patrick McHardy | 923f490 | 2007-02-12 11:12:57 -0800 | [diff] [blame] | 168 | rcu_read_lock(); |
Patrick McHardy | 923f490 | 2007-02-12 11:12:57 -0800 | [diff] [blame] | 169 | l4proto = __nf_ct_l4proto_find(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.l3num, |
| 170 | ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum); |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 171 | if (l4proto && l4proto->destroy) |
| 172 | l4proto->destroy(ct); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 173 | |
Yasuyuki Kozakai | ecfab2c | 2007-07-07 22:23:21 -0700 | [diff] [blame] | 174 | nf_ct_ext_destroy(ct); |
| 175 | |
Patrick McHardy | 982d9a9 | 2007-02-12 11:14:11 -0800 | [diff] [blame] | 176 | rcu_read_unlock(); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 177 | |
| 178 | write_lock_bh(&nf_conntrack_lock); |
| 179 | /* Expectations will have been removed in clean_from_lists, |
| 180 | * except TFTP can create an expectation on the first packet, |
| 181 | * before connection is in the list, so we need to clean here, |
| 182 | * too. */ |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 183 | nf_ct_remove_expectations(ct); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 184 | |
| 185 | /* We overload first tuple to link into unconfirmed list. */ |
| 186 | if (!nf_ct_is_confirmed(ct)) { |
| 187 | BUG_ON(list_empty(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list)); |
| 188 | list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list); |
| 189 | } |
| 190 | |
| 191 | NF_CT_STAT_INC(delete); |
| 192 | write_unlock_bh(&nf_conntrack_lock); |
| 193 | |
| 194 | if (ct->master) |
| 195 | nf_ct_put(ct->master); |
| 196 | |
| 197 | DEBUGP("destroy_conntrack: returning ct=%p to slab\n", ct); |
| 198 | nf_conntrack_free(ct); |
| 199 | } |
| 200 | |
| 201 | static void death_by_timeout(unsigned long ul_conntrack) |
| 202 | { |
| 203 | struct nf_conn *ct = (void *)ul_conntrack; |
Patrick McHardy | 5397e97 | 2007-05-19 14:23:52 -0700 | [diff] [blame] | 204 | struct nf_conn_help *help = nfct_help(ct); |
Patrick McHarrdy | 3c158f7 | 2007-06-05 12:55:27 -0700 | [diff] [blame] | 205 | struct nf_conntrack_helper *helper; |
Patrick McHardy | 5397e97 | 2007-05-19 14:23:52 -0700 | [diff] [blame] | 206 | |
Patrick McHarrdy | 3c158f7 | 2007-06-05 12:55:27 -0700 | [diff] [blame] | 207 | if (help) { |
| 208 | rcu_read_lock(); |
| 209 | helper = rcu_dereference(help->helper); |
| 210 | if (helper && helper->destroy) |
| 211 | helper->destroy(ct); |
| 212 | rcu_read_unlock(); |
| 213 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 214 | |
| 215 | write_lock_bh(&nf_conntrack_lock); |
| 216 | /* Inside lock so preempt is disabled on module removal path. |
| 217 | * Otherwise we can get spurious warnings. */ |
| 218 | NF_CT_STAT_INC(delete_list); |
| 219 | clean_from_lists(ct); |
| 220 | write_unlock_bh(&nf_conntrack_lock); |
| 221 | nf_ct_put(ct); |
| 222 | } |
| 223 | |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 224 | struct nf_conntrack_tuple_hash * |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 225 | __nf_conntrack_find(const struct nf_conntrack_tuple *tuple, |
| 226 | const struct nf_conn *ignored_conntrack) |
| 227 | { |
| 228 | struct nf_conntrack_tuple_hash *h; |
| 229 | unsigned int hash = hash_conntrack(tuple); |
| 230 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 231 | list_for_each_entry(h, &nf_conntrack_hash[hash], list) { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 232 | if (nf_ct_tuplehash_to_ctrack(h) != ignored_conntrack && |
| 233 | nf_ct_tuple_equal(tuple, &h->tuple)) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 234 | NF_CT_STAT_INC(found); |
| 235 | return h; |
| 236 | } |
| 237 | NF_CT_STAT_INC(searched); |
| 238 | } |
| 239 | |
| 240 | return NULL; |
| 241 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 242 | EXPORT_SYMBOL_GPL(__nf_conntrack_find); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 243 | |
| 244 | /* Find a connection corresponding to a tuple. */ |
| 245 | struct nf_conntrack_tuple_hash * |
| 246 | nf_conntrack_find_get(const struct nf_conntrack_tuple *tuple, |
| 247 | const struct nf_conn *ignored_conntrack) |
| 248 | { |
| 249 | struct nf_conntrack_tuple_hash *h; |
| 250 | |
| 251 | read_lock_bh(&nf_conntrack_lock); |
| 252 | h = __nf_conntrack_find(tuple, ignored_conntrack); |
| 253 | if (h) |
| 254 | atomic_inc(&nf_ct_tuplehash_to_ctrack(h)->ct_general.use); |
| 255 | read_unlock_bh(&nf_conntrack_lock); |
| 256 | |
| 257 | return h; |
| 258 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 259 | EXPORT_SYMBOL_GPL(nf_conntrack_find_get); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 260 | |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 261 | static void __nf_conntrack_hash_insert(struct nf_conn *ct, |
| 262 | unsigned int hash, |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 263 | unsigned int repl_hash) |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 264 | { |
| 265 | ct->id = ++nf_conntrack_next_id; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 266 | list_add(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list, |
| 267 | &nf_conntrack_hash[hash]); |
| 268 | list_add(&ct->tuplehash[IP_CT_DIR_REPLY].list, |
| 269 | &nf_conntrack_hash[repl_hash]); |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 270 | } |
| 271 | |
| 272 | void nf_conntrack_hash_insert(struct nf_conn *ct) |
| 273 | { |
| 274 | unsigned int hash, repl_hash; |
| 275 | |
| 276 | hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); |
| 277 | repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| 278 | |
| 279 | write_lock_bh(&nf_conntrack_lock); |
| 280 | __nf_conntrack_hash_insert(ct, hash, repl_hash); |
| 281 | write_unlock_bh(&nf_conntrack_lock); |
| 282 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 283 | EXPORT_SYMBOL_GPL(nf_conntrack_hash_insert); |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 284 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 285 | /* Confirm a connection given skb; places it in hash table */ |
| 286 | int |
| 287 | __nf_conntrack_confirm(struct sk_buff **pskb) |
| 288 | { |
| 289 | unsigned int hash, repl_hash; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 290 | struct nf_conntrack_tuple_hash *h; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 291 | struct nf_conn *ct; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 292 | struct nf_conn_help *help; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 293 | enum ip_conntrack_info ctinfo; |
| 294 | |
| 295 | ct = nf_ct_get(*pskb, &ctinfo); |
| 296 | |
| 297 | /* ipt_REJECT uses nf_conntrack_attach to attach related |
| 298 | ICMP/TCP RST packets in other direction. Actual packet |
| 299 | which created connection will be IP_CT_NEW or for an |
| 300 | expected connection, IP_CT_RELATED. */ |
| 301 | if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) |
| 302 | return NF_ACCEPT; |
| 303 | |
| 304 | hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); |
| 305 | repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| 306 | |
| 307 | /* We're not in hash table, and we refuse to set up related |
| 308 | connections for unconfirmed conns. But packet copies and |
| 309 | REJECT will give spurious warnings here. */ |
| 310 | /* NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 1); */ |
| 311 | |
| 312 | /* No external references means noone else could have |
| 313 | confirmed us. */ |
| 314 | NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); |
| 315 | DEBUGP("Confirming conntrack %p\n", ct); |
| 316 | |
| 317 | write_lock_bh(&nf_conntrack_lock); |
| 318 | |
| 319 | /* See if there's one in the list already, including reverse: |
| 320 | NAT could have grabbed it without realizing, since we're |
| 321 | not in the hash. If there is, we lost race. */ |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 322 | list_for_each_entry(h, &nf_conntrack_hash[hash], list) |
| 323 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, |
| 324 | &h->tuple)) |
| 325 | goto out; |
| 326 | list_for_each_entry(h, &nf_conntrack_hash[repl_hash], list) |
| 327 | if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple, |
| 328 | &h->tuple)) |
| 329 | goto out; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 330 | |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 331 | /* Remove from unconfirmed list */ |
| 332 | list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list); |
| 333 | |
| 334 | __nf_conntrack_hash_insert(ct, hash, repl_hash); |
| 335 | /* Timer relative to confirmation time, not original |
| 336 | setting time, otherwise we'd get timer wrap in |
| 337 | weird delay cases. */ |
| 338 | ct->timeout.expires += jiffies; |
| 339 | add_timer(&ct->timeout); |
| 340 | atomic_inc(&ct->ct_general.use); |
| 341 | set_bit(IPS_CONFIRMED_BIT, &ct->status); |
| 342 | NF_CT_STAT_INC(insert); |
| 343 | write_unlock_bh(&nf_conntrack_lock); |
| 344 | help = nfct_help(ct); |
| 345 | if (help && help->helper) |
| 346 | nf_conntrack_event_cache(IPCT_HELPER, *pskb); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 347 | #ifdef CONFIG_NF_NAT_NEEDED |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 348 | if (test_bit(IPS_SRC_NAT_DONE_BIT, &ct->status) || |
| 349 | test_bit(IPS_DST_NAT_DONE_BIT, &ct->status)) |
| 350 | nf_conntrack_event_cache(IPCT_NATINFO, *pskb); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 351 | #endif |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 352 | nf_conntrack_event_cache(master_ct(ct) ? |
| 353 | IPCT_RELATED : IPCT_NEW, *pskb); |
| 354 | return NF_ACCEPT; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 355 | |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 356 | out: |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 357 | NF_CT_STAT_INC(insert_failed); |
| 358 | write_unlock_bh(&nf_conntrack_lock); |
| 359 | return NF_DROP; |
| 360 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 361 | EXPORT_SYMBOL_GPL(__nf_conntrack_confirm); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 362 | |
| 363 | /* Returns true if a connection correspondings to the tuple (required |
| 364 | for NAT). */ |
| 365 | int |
| 366 | nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple, |
| 367 | const struct nf_conn *ignored_conntrack) |
| 368 | { |
| 369 | struct nf_conntrack_tuple_hash *h; |
| 370 | |
| 371 | read_lock_bh(&nf_conntrack_lock); |
| 372 | h = __nf_conntrack_find(tuple, ignored_conntrack); |
| 373 | read_unlock_bh(&nf_conntrack_lock); |
| 374 | |
| 375 | return h != NULL; |
| 376 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 377 | EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 378 | |
| 379 | /* There's a small race here where we may free a just-assured |
| 380 | connection. Too bad: we're in trouble anyway. */ |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 381 | static int early_drop(struct list_head *chain) |
| 382 | { |
| 383 | /* Traverse backwards: gives us oldest, which is roughly LRU */ |
| 384 | struct nf_conntrack_tuple_hash *h; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 385 | struct nf_conn *ct = NULL, *tmp; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 386 | int dropped = 0; |
| 387 | |
| 388 | read_lock_bh(&nf_conntrack_lock); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 389 | list_for_each_entry_reverse(h, chain, list) { |
| 390 | tmp = nf_ct_tuplehash_to_ctrack(h); |
| 391 | if (!test_bit(IPS_ASSURED_BIT, &tmp->status)) { |
| 392 | ct = tmp; |
| 393 | atomic_inc(&ct->ct_general.use); |
| 394 | break; |
| 395 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 396 | } |
| 397 | read_unlock_bh(&nf_conntrack_lock); |
| 398 | |
| 399 | if (!ct) |
| 400 | return dropped; |
| 401 | |
| 402 | if (del_timer(&ct->timeout)) { |
| 403 | death_by_timeout((unsigned long)ct); |
| 404 | dropped = 1; |
Patrick McHardy | c0e912d | 2007-02-12 11:13:43 -0800 | [diff] [blame] | 405 | NF_CT_STAT_INC_ATOMIC(early_drop); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 406 | } |
| 407 | nf_ct_put(ct); |
| 408 | return dropped; |
| 409 | } |
| 410 | |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 411 | struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig, |
| 412 | const struct nf_conntrack_tuple *repl) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 413 | { |
| 414 | struct nf_conn *conntrack = NULL; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 415 | |
Harald Welte | dc808fe | 2006-03-20 17:56:32 -0800 | [diff] [blame] | 416 | if (unlikely(!nf_conntrack_hash_rnd_initted)) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 417 | get_random_bytes(&nf_conntrack_hash_rnd, 4); |
| 418 | nf_conntrack_hash_rnd_initted = 1; |
| 419 | } |
| 420 | |
Pablo Neira Ayuso | 5251e2d | 2006-09-20 12:01:06 -0700 | [diff] [blame] | 421 | /* We don't want any race condition at early drop stage */ |
| 422 | atomic_inc(&nf_conntrack_count); |
| 423 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 424 | if (nf_conntrack_max |
Pablo Neira Ayuso | 5251e2d | 2006-09-20 12:01:06 -0700 | [diff] [blame] | 425 | && atomic_read(&nf_conntrack_count) > nf_conntrack_max) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 426 | unsigned int hash = hash_conntrack(orig); |
| 427 | /* Try dropping from this hash chain. */ |
| 428 | if (!early_drop(&nf_conntrack_hash[hash])) { |
Pablo Neira Ayuso | 5251e2d | 2006-09-20 12:01:06 -0700 | [diff] [blame] | 429 | atomic_dec(&nf_conntrack_count); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 430 | if (net_ratelimit()) |
| 431 | printk(KERN_WARNING |
| 432 | "nf_conntrack: table full, dropping" |
| 433 | " packet.\n"); |
| 434 | return ERR_PTR(-ENOMEM); |
| 435 | } |
| 436 | } |
| 437 | |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 438 | conntrack = kmem_cache_zalloc(nf_conntrack_cachep, GFP_ATOMIC); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 439 | if (conntrack == NULL) { |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 440 | DEBUGP("nf_conntrack_alloc: Can't alloc conntrack.\n"); |
| 441 | atomic_dec(&nf_conntrack_count); |
| 442 | return ERR_PTR(-ENOMEM); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 443 | } |
| 444 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 445 | atomic_set(&conntrack->ct_general.use, 1); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 446 | conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig; |
| 447 | conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl; |
| 448 | /* Don't set timer yet: wait for confirmation */ |
Patrick McHardy | e6f689d | 2007-03-23 11:16:30 -0700 | [diff] [blame] | 449 | setup_timer(&conntrack->timeout, death_by_timeout, |
| 450 | (unsigned long)conntrack); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 451 | |
Pablo Neira Ayuso | 5251e2d | 2006-09-20 12:01:06 -0700 | [diff] [blame] | 452 | return conntrack; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 453 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 454 | EXPORT_SYMBOL_GPL(nf_conntrack_alloc); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 455 | |
| 456 | void nf_conntrack_free(struct nf_conn *conntrack) |
| 457 | { |
Yasuyuki Kozakai | ecfab2c | 2007-07-07 22:23:21 -0700 | [diff] [blame] | 458 | nf_ct_ext_free(conntrack); |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 459 | kmem_cache_free(nf_conntrack_cachep, conntrack); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 460 | atomic_dec(&nf_conntrack_count); |
| 461 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 462 | EXPORT_SYMBOL_GPL(nf_conntrack_free); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 463 | |
| 464 | /* Allocate a new conntrack: we return -ENOMEM if classification |
| 465 | failed due to stress. Otherwise it really is unclassifiable. */ |
| 466 | static struct nf_conntrack_tuple_hash * |
| 467 | init_conntrack(const struct nf_conntrack_tuple *tuple, |
| 468 | struct nf_conntrack_l3proto *l3proto, |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 469 | struct nf_conntrack_l4proto *l4proto, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 470 | struct sk_buff *skb, |
| 471 | unsigned int dataoff) |
| 472 | { |
| 473 | struct nf_conn *conntrack; |
Patrick McHarrdy | 3c158f7 | 2007-06-05 12:55:27 -0700 | [diff] [blame] | 474 | struct nf_conn_help *help; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 475 | struct nf_conntrack_tuple repl_tuple; |
| 476 | struct nf_conntrack_expect *exp; |
| 477 | |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 478 | if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 479 | DEBUGP("Can't invert tuple.\n"); |
| 480 | return NULL; |
| 481 | } |
| 482 | |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 483 | conntrack = nf_conntrack_alloc(tuple, &repl_tuple); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 484 | if (conntrack == NULL || IS_ERR(conntrack)) { |
| 485 | DEBUGP("Can't allocate conntrack.\n"); |
| 486 | return (struct nf_conntrack_tuple_hash *)conntrack; |
| 487 | } |
| 488 | |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 489 | if (!l4proto->new(conntrack, skb, dataoff)) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 490 | nf_conntrack_free(conntrack); |
| 491 | DEBUGP("init conntrack: can't track with proto module\n"); |
| 492 | return NULL; |
| 493 | } |
| 494 | |
| 495 | write_lock_bh(&nf_conntrack_lock); |
| 496 | exp = find_expectation(tuple); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 497 | if (exp) { |
| 498 | DEBUGP("conntrack: expectation arrives ct=%p exp=%p\n", |
| 499 | conntrack, exp); |
| 500 | /* Welcome, Mr. Bond. We've been expecting you... */ |
| 501 | __set_bit(IPS_EXPECTED_BIT, &conntrack->status); |
| 502 | conntrack->master = exp->master; |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 503 | if (exp->helper) { |
| 504 | help = nf_ct_ext_add(conntrack, NF_CT_EXT_HELPER, |
| 505 | GFP_ATOMIC); |
| 506 | if (help) |
| 507 | rcu_assign_pointer(help->helper, exp->helper); |
| 508 | else |
| 509 | DEBUGP("failed to add helper extension area"); |
| 510 | } |
| 511 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 512 | #ifdef CONFIG_NF_CONNTRACK_MARK |
| 513 | conntrack->mark = exp->master->mark; |
| 514 | #endif |
James Morris | 7c9728c | 2006-06-09 00:31:46 -0700 | [diff] [blame] | 515 | #ifdef CONFIG_NF_CONNTRACK_SECMARK |
| 516 | conntrack->secmark = exp->master->secmark; |
| 517 | #endif |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 518 | nf_conntrack_get(&conntrack->master->ct_general); |
| 519 | NF_CT_STAT_INC(expect_new); |
Yasuyuki Kozakai | 22e7410 | 2006-11-27 10:25:59 -0800 | [diff] [blame] | 520 | } else { |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 521 | struct nf_conntrack_helper *helper; |
| 522 | |
| 523 | helper = __nf_ct_helper_find(&repl_tuple); |
| 524 | if (helper) { |
| 525 | help = nf_ct_ext_add(conntrack, NF_CT_EXT_HELPER, |
| 526 | GFP_ATOMIC); |
| 527 | if (help) |
| 528 | /* not in hash table yet, so not strictly |
| 529 | necessary */ |
| 530 | rcu_assign_pointer(help->helper, helper); |
| 531 | else |
| 532 | DEBUGP("failed to add helper extension area"); |
Patrick McHarrdy | 3c158f7 | 2007-06-05 12:55:27 -0700 | [diff] [blame] | 533 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 534 | NF_CT_STAT_INC(new); |
Yasuyuki Kozakai | 22e7410 | 2006-11-27 10:25:59 -0800 | [diff] [blame] | 535 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 536 | |
| 537 | /* Overload tuple linked list to put us in unconfirmed list. */ |
| 538 | list_add(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].list, &unconfirmed); |
| 539 | |
| 540 | write_unlock_bh(&nf_conntrack_lock); |
| 541 | |
| 542 | if (exp) { |
| 543 | if (exp->expectfn) |
| 544 | exp->expectfn(conntrack, exp); |
| 545 | nf_conntrack_expect_put(exp); |
| 546 | } |
| 547 | |
| 548 | return &conntrack->tuplehash[IP_CT_DIR_ORIGINAL]; |
| 549 | } |
| 550 | |
| 551 | /* On success, returns conntrack ptr, sets skb->nfct and ctinfo */ |
| 552 | static inline struct nf_conn * |
| 553 | resolve_normal_ct(struct sk_buff *skb, |
| 554 | unsigned int dataoff, |
| 555 | u_int16_t l3num, |
| 556 | u_int8_t protonum, |
| 557 | struct nf_conntrack_l3proto *l3proto, |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 558 | struct nf_conntrack_l4proto *l4proto, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 559 | int *set_reply, |
| 560 | enum ip_conntrack_info *ctinfo) |
| 561 | { |
| 562 | struct nf_conntrack_tuple tuple; |
| 563 | struct nf_conntrack_tuple_hash *h; |
| 564 | struct nf_conn *ct; |
| 565 | |
Arnaldo Carvalho de Melo | bbe735e | 2007-03-10 22:16:10 -0300 | [diff] [blame] | 566 | if (!nf_ct_get_tuple(skb, skb_network_offset(skb), |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 567 | dataoff, l3num, protonum, &tuple, l3proto, |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 568 | l4proto)) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 569 | DEBUGP("resolve_normal_ct: Can't get tuple\n"); |
| 570 | return NULL; |
| 571 | } |
| 572 | |
| 573 | /* look for tuple match */ |
| 574 | h = nf_conntrack_find_get(&tuple, NULL); |
| 575 | if (!h) { |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 576 | h = init_conntrack(&tuple, l3proto, l4proto, skb, dataoff); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 577 | if (!h) |
| 578 | return NULL; |
| 579 | if (IS_ERR(h)) |
| 580 | return (void *)h; |
| 581 | } |
| 582 | ct = nf_ct_tuplehash_to_ctrack(h); |
| 583 | |
| 584 | /* It exists; we have (non-exclusive) reference. */ |
| 585 | if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) { |
| 586 | *ctinfo = IP_CT_ESTABLISHED + IP_CT_IS_REPLY; |
| 587 | /* Please set reply bit if this packet OK */ |
| 588 | *set_reply = 1; |
| 589 | } else { |
| 590 | /* Once we've had two way comms, always ESTABLISHED. */ |
| 591 | if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { |
| 592 | DEBUGP("nf_conntrack_in: normal packet for %p\n", ct); |
| 593 | *ctinfo = IP_CT_ESTABLISHED; |
| 594 | } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) { |
| 595 | DEBUGP("nf_conntrack_in: related packet for %p\n", ct); |
| 596 | *ctinfo = IP_CT_RELATED; |
| 597 | } else { |
| 598 | DEBUGP("nf_conntrack_in: new packet for %p\n", ct); |
| 599 | *ctinfo = IP_CT_NEW; |
| 600 | } |
| 601 | *set_reply = 0; |
| 602 | } |
| 603 | skb->nfct = &ct->ct_general; |
| 604 | skb->nfctinfo = *ctinfo; |
| 605 | return ct; |
| 606 | } |
| 607 | |
| 608 | unsigned int |
| 609 | nf_conntrack_in(int pf, unsigned int hooknum, struct sk_buff **pskb) |
| 610 | { |
| 611 | struct nf_conn *ct; |
| 612 | enum ip_conntrack_info ctinfo; |
| 613 | struct nf_conntrack_l3proto *l3proto; |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 614 | struct nf_conntrack_l4proto *l4proto; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 615 | unsigned int dataoff; |
| 616 | u_int8_t protonum; |
| 617 | int set_reply = 0; |
| 618 | int ret; |
| 619 | |
| 620 | /* Previously seen (loopback or untracked)? Ignore. */ |
| 621 | if ((*pskb)->nfct) { |
Patrick McHardy | c0e912d | 2007-02-12 11:13:43 -0800 | [diff] [blame] | 622 | NF_CT_STAT_INC_ATOMIC(ignore); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 623 | return NF_ACCEPT; |
| 624 | } |
| 625 | |
Patrick McHardy | 923f490 | 2007-02-12 11:12:57 -0800 | [diff] [blame] | 626 | /* rcu_read_lock()ed by nf_hook_slow */ |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 627 | l3proto = __nf_ct_l3proto_find((u_int16_t)pf); |
Patrick McHardy | 923f490 | 2007-02-12 11:12:57 -0800 | [diff] [blame] | 628 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 629 | if ((ret = l3proto->prepare(pskb, hooknum, &dataoff, &protonum)) <= 0) { |
| 630 | DEBUGP("not prepared to track yet or error occured\n"); |
| 631 | return -ret; |
| 632 | } |
| 633 | |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 634 | l4proto = __nf_ct_l4proto_find((u_int16_t)pf, protonum); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 635 | |
| 636 | /* It may be an special packet, error, unclean... |
| 637 | * inverse of the return code tells to the netfilter |
| 638 | * core what to do with the packet. */ |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 639 | if (l4proto->error != NULL && |
| 640 | (ret = l4proto->error(*pskb, dataoff, &ctinfo, pf, hooknum)) <= 0) { |
Patrick McHardy | c0e912d | 2007-02-12 11:13:43 -0800 | [diff] [blame] | 641 | NF_CT_STAT_INC_ATOMIC(error); |
| 642 | NF_CT_STAT_INC_ATOMIC(invalid); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 643 | return -ret; |
| 644 | } |
| 645 | |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 646 | ct = resolve_normal_ct(*pskb, dataoff, pf, protonum, l3proto, l4proto, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 647 | &set_reply, &ctinfo); |
| 648 | if (!ct) { |
| 649 | /* Not valid part of a connection */ |
Patrick McHardy | c0e912d | 2007-02-12 11:13:43 -0800 | [diff] [blame] | 650 | NF_CT_STAT_INC_ATOMIC(invalid); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 651 | return NF_ACCEPT; |
| 652 | } |
| 653 | |
| 654 | if (IS_ERR(ct)) { |
| 655 | /* Too stressed to deal. */ |
Patrick McHardy | c0e912d | 2007-02-12 11:13:43 -0800 | [diff] [blame] | 656 | NF_CT_STAT_INC_ATOMIC(drop); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 657 | return NF_DROP; |
| 658 | } |
| 659 | |
| 660 | NF_CT_ASSERT((*pskb)->nfct); |
| 661 | |
Martin Josefsson | 605dcad | 2006-11-29 02:35:06 +0100 | [diff] [blame] | 662 | ret = l4proto->packet(ct, *pskb, dataoff, ctinfo, pf, hooknum); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 663 | if (ret < 0) { |
| 664 | /* Invalid: inverse of the return code tells |
| 665 | * the netfilter core what to do */ |
| 666 | DEBUGP("nf_conntrack_in: Can't track with proto module\n"); |
| 667 | nf_conntrack_put((*pskb)->nfct); |
| 668 | (*pskb)->nfct = NULL; |
Patrick McHardy | c0e912d | 2007-02-12 11:13:43 -0800 | [diff] [blame] | 669 | NF_CT_STAT_INC_ATOMIC(invalid); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 670 | return -ret; |
| 671 | } |
| 672 | |
| 673 | if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status)) |
| 674 | nf_conntrack_event_cache(IPCT_STATUS, *pskb); |
| 675 | |
| 676 | return ret; |
| 677 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 678 | EXPORT_SYMBOL_GPL(nf_conntrack_in); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 679 | |
| 680 | int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse, |
| 681 | const struct nf_conntrack_tuple *orig) |
| 682 | { |
Patrick McHardy | 923f490 | 2007-02-12 11:12:57 -0800 | [diff] [blame] | 683 | int ret; |
| 684 | |
| 685 | rcu_read_lock(); |
| 686 | ret = nf_ct_invert_tuple(inverse, orig, |
| 687 | __nf_ct_l3proto_find(orig->src.l3num), |
| 688 | __nf_ct_l4proto_find(orig->src.l3num, |
| 689 | orig->dst.protonum)); |
| 690 | rcu_read_unlock(); |
| 691 | return ret; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 692 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 693 | EXPORT_SYMBOL_GPL(nf_ct_invert_tuplepr); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 694 | |
Jozsef Kadlecsik | 5b1158e | 2006-12-02 22:07:13 -0800 | [diff] [blame] | 695 | /* Alter reply tuple (maybe alter helper). This is for NAT, and is |
| 696 | implicitly racy: see __nf_conntrack_confirm */ |
| 697 | void nf_conntrack_alter_reply(struct nf_conn *ct, |
| 698 | const struct nf_conntrack_tuple *newreply) |
| 699 | { |
| 700 | struct nf_conn_help *help = nfct_help(ct); |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 701 | struct nf_conntrack_helper *helper; |
Jozsef Kadlecsik | 5b1158e | 2006-12-02 22:07:13 -0800 | [diff] [blame] | 702 | |
| 703 | write_lock_bh(&nf_conntrack_lock); |
| 704 | /* Should be unconfirmed, so not in hash table yet */ |
| 705 | NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); |
| 706 | |
| 707 | DEBUGP("Altering reply tuple of %p to ", ct); |
| 708 | NF_CT_DUMP_TUPLE(newreply); |
| 709 | |
| 710 | ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply; |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 711 | if (ct->master || (help && help->expecting != 0)) |
| 712 | goto out; |
| 713 | |
| 714 | helper = __nf_ct_helper_find(newreply); |
| 715 | if (helper == NULL) { |
| 716 | if (help) |
| 717 | rcu_assign_pointer(help->helper, NULL); |
| 718 | goto out; |
Yasuyuki Kozakai | 5d78a84 | 2007-05-10 14:16:24 -0700 | [diff] [blame] | 719 | } |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 720 | |
| 721 | if (help == NULL) { |
| 722 | help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, GFP_ATOMIC); |
| 723 | if (help == NULL) { |
| 724 | DEBUGP("failed to add helper extension area"); |
| 725 | goto out; |
| 726 | } |
| 727 | } else { |
| 728 | memset(&help->help, 0, sizeof(help->help)); |
| 729 | } |
| 730 | |
| 731 | rcu_assign_pointer(help->helper, helper); |
| 732 | out: |
Jozsef Kadlecsik | 5b1158e | 2006-12-02 22:07:13 -0800 | [diff] [blame] | 733 | write_unlock_bh(&nf_conntrack_lock); |
| 734 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 735 | EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply); |
Jozsef Kadlecsik | 5b1158e | 2006-12-02 22:07:13 -0800 | [diff] [blame] | 736 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 737 | /* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */ |
| 738 | void __nf_ct_refresh_acct(struct nf_conn *ct, |
| 739 | enum ip_conntrack_info ctinfo, |
| 740 | const struct sk_buff *skb, |
| 741 | unsigned long extra_jiffies, |
| 742 | int do_acct) |
| 743 | { |
| 744 | int event = 0; |
| 745 | |
| 746 | NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct); |
| 747 | NF_CT_ASSERT(skb); |
| 748 | |
| 749 | write_lock_bh(&nf_conntrack_lock); |
| 750 | |
Eric Leblond | 997ae83 | 2006-05-29 18:24:20 -0700 | [diff] [blame] | 751 | /* Only update if this is not a fixed timeout */ |
| 752 | if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status)) { |
| 753 | write_unlock_bh(&nf_conntrack_lock); |
| 754 | return; |
| 755 | } |
| 756 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 757 | /* If not in hash table, timer will not be active yet */ |
| 758 | if (!nf_ct_is_confirmed(ct)) { |
| 759 | ct->timeout.expires = extra_jiffies; |
| 760 | event = IPCT_REFRESH; |
| 761 | } else { |
Martin Josefsson | be00c8e | 2006-11-29 02:35:12 +0100 | [diff] [blame] | 762 | unsigned long newtime = jiffies + extra_jiffies; |
| 763 | |
| 764 | /* Only update the timeout if the new timeout is at least |
| 765 | HZ jiffies from the old timeout. Need del_timer for race |
| 766 | avoidance (may already be dying). */ |
| 767 | if (newtime - ct->timeout.expires >= HZ |
| 768 | && del_timer(&ct->timeout)) { |
| 769 | ct->timeout.expires = newtime; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 770 | add_timer(&ct->timeout); |
| 771 | event = IPCT_REFRESH; |
| 772 | } |
| 773 | } |
| 774 | |
| 775 | #ifdef CONFIG_NF_CT_ACCT |
| 776 | if (do_acct) { |
| 777 | ct->counters[CTINFO2DIR(ctinfo)].packets++; |
| 778 | ct->counters[CTINFO2DIR(ctinfo)].bytes += |
Arnaldo Carvalho de Melo | bbe735e | 2007-03-10 22:16:10 -0300 | [diff] [blame] | 779 | skb->len - skb_network_offset(skb); |
Martin Josefsson | 3ffd5ee | 2006-11-29 02:35:10 +0100 | [diff] [blame] | 780 | |
| 781 | if ((ct->counters[CTINFO2DIR(ctinfo)].packets & 0x80000000) |
| 782 | || (ct->counters[CTINFO2DIR(ctinfo)].bytes & 0x80000000)) |
| 783 | event |= IPCT_COUNTER_FILLING; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 784 | } |
| 785 | #endif |
| 786 | |
| 787 | write_unlock_bh(&nf_conntrack_lock); |
| 788 | |
| 789 | /* must be unlocked when calling event cache */ |
| 790 | if (event) |
| 791 | nf_conntrack_event_cache(event, skb); |
| 792 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 793 | EXPORT_SYMBOL_GPL(__nf_ct_refresh_acct); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 794 | |
Patrick McHardy | e281db5c | 2007-03-04 15:57:25 -0800 | [diff] [blame] | 795 | #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 796 | |
| 797 | #include <linux/netfilter/nfnetlink.h> |
| 798 | #include <linux/netfilter/nfnetlink_conntrack.h> |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 799 | #include <linux/mutex.h> |
| 800 | |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 801 | |
| 802 | /* Generic function for tcp/udp/sctp/dccp and alike. This needs to be |
| 803 | * in ip_conntrack_core, since we don't want the protocols to autoload |
| 804 | * or depend on ctnetlink */ |
| 805 | int nf_ct_port_tuple_to_nfattr(struct sk_buff *skb, |
| 806 | const struct nf_conntrack_tuple *tuple) |
| 807 | { |
| 808 | NFA_PUT(skb, CTA_PROTO_SRC_PORT, sizeof(u_int16_t), |
| 809 | &tuple->src.u.tcp.port); |
| 810 | NFA_PUT(skb, CTA_PROTO_DST_PORT, sizeof(u_int16_t), |
| 811 | &tuple->dst.u.tcp.port); |
| 812 | return 0; |
| 813 | |
| 814 | nfattr_failure: |
| 815 | return -1; |
| 816 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 817 | EXPORT_SYMBOL_GPL(nf_ct_port_tuple_to_nfattr); |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 818 | |
| 819 | static const size_t cta_min_proto[CTA_PROTO_MAX] = { |
| 820 | [CTA_PROTO_SRC_PORT-1] = sizeof(u_int16_t), |
| 821 | [CTA_PROTO_DST_PORT-1] = sizeof(u_int16_t) |
| 822 | }; |
| 823 | |
| 824 | int nf_ct_port_nfattr_to_tuple(struct nfattr *tb[], |
| 825 | struct nf_conntrack_tuple *t) |
| 826 | { |
| 827 | if (!tb[CTA_PROTO_SRC_PORT-1] || !tb[CTA_PROTO_DST_PORT-1]) |
| 828 | return -EINVAL; |
| 829 | |
| 830 | if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto)) |
| 831 | return -EINVAL; |
| 832 | |
Patrick McHardy | bff9a89 | 2006-12-02 22:05:08 -0800 | [diff] [blame] | 833 | t->src.u.tcp.port = *(__be16 *)NFA_DATA(tb[CTA_PROTO_SRC_PORT-1]); |
| 834 | t->dst.u.tcp.port = *(__be16 *)NFA_DATA(tb[CTA_PROTO_DST_PORT-1]); |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 835 | |
| 836 | return 0; |
| 837 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 838 | EXPORT_SYMBOL_GPL(nf_ct_port_nfattr_to_tuple); |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 839 | #endif |
| 840 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 841 | /* Used by ipt_REJECT and ip6t_REJECT. */ |
| 842 | void __nf_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb) |
| 843 | { |
| 844 | struct nf_conn *ct; |
| 845 | enum ip_conntrack_info ctinfo; |
| 846 | |
| 847 | /* This ICMP is in reverse direction to the packet which caused it */ |
| 848 | ct = nf_ct_get(skb, &ctinfo); |
| 849 | if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) |
| 850 | ctinfo = IP_CT_RELATED + IP_CT_IS_REPLY; |
| 851 | else |
| 852 | ctinfo = IP_CT_RELATED; |
| 853 | |
| 854 | /* Attach to new skbuff, and increment count */ |
| 855 | nskb->nfct = &ct->ct_general; |
| 856 | nskb->nfctinfo = ctinfo; |
| 857 | nf_conntrack_get(nskb->nfct); |
| 858 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 859 | EXPORT_SYMBOL_GPL(__nf_conntrack_attach); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 860 | |
| 861 | static inline int |
| 862 | do_iter(const struct nf_conntrack_tuple_hash *i, |
| 863 | int (*iter)(struct nf_conn *i, void *data), |
| 864 | void *data) |
| 865 | { |
| 866 | return iter(nf_ct_tuplehash_to_ctrack(i), data); |
| 867 | } |
| 868 | |
| 869 | /* Bring out ya dead! */ |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 870 | static struct nf_conn * |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 871 | get_next_corpse(int (*iter)(struct nf_conn *i, void *data), |
| 872 | void *data, unsigned int *bucket) |
| 873 | { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 874 | struct nf_conntrack_tuple_hash *h; |
| 875 | struct nf_conn *ct; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 876 | |
| 877 | write_lock_bh(&nf_conntrack_lock); |
| 878 | for (; *bucket < nf_conntrack_htable_size; (*bucket)++) { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 879 | list_for_each_entry(h, &nf_conntrack_hash[*bucket], list) { |
| 880 | ct = nf_ct_tuplehash_to_ctrack(h); |
| 881 | if (iter(ct, data)) |
| 882 | goto found; |
| 883 | } |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 884 | } |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 885 | list_for_each_entry(h, &unconfirmed, list) { |
| 886 | ct = nf_ct_tuplehash_to_ctrack(h); |
| 887 | if (iter(ct, data)) |
Patrick McHardy | ec68e97 | 2007-03-04 15:57:01 -0800 | [diff] [blame] | 888 | set_bit(IPS_DYING_BIT, &ct->status); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 889 | } |
Martin Josefsson | c073e3f | 2006-10-30 15:13:58 -0800 | [diff] [blame] | 890 | write_unlock_bh(&nf_conntrack_lock); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 891 | return NULL; |
| 892 | found: |
Martin Josefsson | c073e3f | 2006-10-30 15:13:58 -0800 | [diff] [blame] | 893 | atomic_inc(&ct->ct_general.use); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 894 | write_unlock_bh(&nf_conntrack_lock); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 895 | return ct; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 896 | } |
| 897 | |
| 898 | void |
| 899 | nf_ct_iterate_cleanup(int (*iter)(struct nf_conn *i, void *data), void *data) |
| 900 | { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 901 | struct nf_conn *ct; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 902 | unsigned int bucket = 0; |
| 903 | |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 904 | while ((ct = get_next_corpse(iter, data, &bucket)) != NULL) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 905 | /* Time to push up daises... */ |
| 906 | if (del_timer(&ct->timeout)) |
| 907 | death_by_timeout((unsigned long)ct); |
| 908 | /* ... else the timer will get him soon. */ |
| 909 | |
| 910 | nf_ct_put(ct); |
| 911 | } |
| 912 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 913 | EXPORT_SYMBOL_GPL(nf_ct_iterate_cleanup); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 914 | |
| 915 | static int kill_all(struct nf_conn *i, void *data) |
| 916 | { |
| 917 | return 1; |
| 918 | } |
| 919 | |
| 920 | static void free_conntrack_hash(struct list_head *hash, int vmalloced, int size) |
| 921 | { |
| 922 | if (vmalloced) |
| 923 | vfree(hash); |
| 924 | else |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 925 | free_pages((unsigned long)hash, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 926 | get_order(sizeof(struct list_head) * size)); |
| 927 | } |
| 928 | |
Randy Dunlap | 272491e | 2006-12-07 01:17:24 -0800 | [diff] [blame] | 929 | void nf_conntrack_flush(void) |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 930 | { |
| 931 | nf_ct_iterate_cleanup(kill_all, NULL); |
| 932 | } |
Patrick McHardy | 13b1833 | 2006-12-02 22:11:25 -0800 | [diff] [blame] | 933 | EXPORT_SYMBOL_GPL(nf_conntrack_flush); |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 934 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 935 | /* Mishearing the voices in his head, our hero wonders how he's |
| 936 | supposed to kill the mall. */ |
| 937 | void nf_conntrack_cleanup(void) |
| 938 | { |
Patrick McHardy | c3a47ab | 2007-02-12 11:09:19 -0800 | [diff] [blame] | 939 | rcu_assign_pointer(ip_ct_attach, NULL); |
Yasuyuki Kozakai | 7d3cdc6 | 2006-02-15 15:22:21 -0800 | [diff] [blame] | 940 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 941 | /* This makes sure all current packets have passed through |
| 942 | netfilter framework. Roll on, two-stage module |
| 943 | delete... */ |
| 944 | synchronize_net(); |
| 945 | |
| 946 | nf_ct_event_cache_flush(); |
| 947 | i_see_dead_people: |
Pablo Neira Ayuso | c1d10ad | 2006-01-05 12:19:05 -0800 | [diff] [blame] | 948 | nf_conntrack_flush(); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 949 | if (atomic_read(&nf_conntrack_count) != 0) { |
| 950 | schedule(); |
| 951 | goto i_see_dead_people; |
| 952 | } |
Patrick McHardy | 6636568 | 2005-12-05 13:36:50 -0800 | [diff] [blame] | 953 | /* wait until all references to nf_conntrack_untracked are dropped */ |
| 954 | while (atomic_read(&nf_conntrack_untracked.ct_general.use) > 1) |
| 955 | schedule(); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 956 | |
Yasuyuki Kozakai | de6e05c | 2007-03-23 11:17:27 -0700 | [diff] [blame] | 957 | rcu_assign_pointer(nf_ct_destroy, NULL); |
| 958 | |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 959 | kmem_cache_destroy(nf_conntrack_cachep); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 960 | kmem_cache_destroy(nf_conntrack_expect_cachep); |
| 961 | free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc, |
| 962 | nf_conntrack_htable_size); |
KOVACS Krisztian | 5a6f294 | 2005-11-15 16:47:34 -0800 | [diff] [blame] | 963 | |
Patrick McHardy | ac5357e | 2007-03-14 16:38:25 -0700 | [diff] [blame] | 964 | nf_conntrack_proto_fini(); |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 965 | nf_conntrack_helper_fini(); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 966 | } |
| 967 | |
Patrick McHardy | 8e5105a | 2007-07-07 22:27:33 -0700 | [diff] [blame^] | 968 | static struct list_head *alloc_hashtable(int *sizep, int *vmalloced) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 969 | { |
| 970 | struct list_head *hash; |
Patrick McHardy | 8e5105a | 2007-07-07 22:27:33 -0700 | [diff] [blame^] | 971 | unsigned int size, i; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 972 | |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 973 | *vmalloced = 0; |
Patrick McHardy | 8e5105a | 2007-07-07 22:27:33 -0700 | [diff] [blame^] | 974 | |
| 975 | size = *sizep = roundup(*sizep, PAGE_SIZE / sizeof(struct list_head)); |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 976 | hash = (void*)__get_free_pages(GFP_KERNEL, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 977 | get_order(sizeof(struct list_head) |
| 978 | * size)); |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 979 | if (!hash) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 980 | *vmalloced = 1; |
| 981 | printk(KERN_WARNING "nf_conntrack: falling back to vmalloc.\n"); |
| 982 | hash = vmalloc(sizeof(struct list_head) * size); |
| 983 | } |
| 984 | |
| 985 | if (hash) |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 986 | for (i = 0; i < size; i++) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 987 | INIT_LIST_HEAD(&hash[i]); |
| 988 | |
| 989 | return hash; |
| 990 | } |
| 991 | |
| 992 | int set_hashsize(const char *val, struct kernel_param *kp) |
| 993 | { |
| 994 | int i, bucket, hashsize, vmalloced; |
| 995 | int old_vmalloced, old_size; |
| 996 | int rnd; |
| 997 | struct list_head *hash, *old_hash; |
| 998 | struct nf_conntrack_tuple_hash *h; |
| 999 | |
| 1000 | /* On boot, we can set this without any fancy locking. */ |
| 1001 | if (!nf_conntrack_htable_size) |
| 1002 | return param_set_uint(val, kp); |
| 1003 | |
| 1004 | hashsize = simple_strtol(val, NULL, 0); |
| 1005 | if (!hashsize) |
| 1006 | return -EINVAL; |
| 1007 | |
Patrick McHardy | 8e5105a | 2007-07-07 22:27:33 -0700 | [diff] [blame^] | 1008 | hash = alloc_hashtable(&hashsize, &vmalloced); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1009 | if (!hash) |
| 1010 | return -ENOMEM; |
| 1011 | |
| 1012 | /* We have to rehahs for the new table anyway, so we also can |
| 1013 | * use a newrandom seed */ |
| 1014 | get_random_bytes(&rnd, 4); |
| 1015 | |
| 1016 | write_lock_bh(&nf_conntrack_lock); |
| 1017 | for (i = 0; i < nf_conntrack_htable_size; i++) { |
| 1018 | while (!list_empty(&nf_conntrack_hash[i])) { |
| 1019 | h = list_entry(nf_conntrack_hash[i].next, |
| 1020 | struct nf_conntrack_tuple_hash, list); |
| 1021 | list_del(&h->list); |
| 1022 | bucket = __hash_conntrack(&h->tuple, hashsize, rnd); |
| 1023 | list_add_tail(&h->list, &hash[bucket]); |
| 1024 | } |
| 1025 | } |
| 1026 | old_size = nf_conntrack_htable_size; |
| 1027 | old_vmalloced = nf_conntrack_vmalloc; |
| 1028 | old_hash = nf_conntrack_hash; |
| 1029 | |
| 1030 | nf_conntrack_htable_size = hashsize; |
| 1031 | nf_conntrack_vmalloc = vmalloced; |
| 1032 | nf_conntrack_hash = hash; |
| 1033 | nf_conntrack_hash_rnd = rnd; |
| 1034 | write_unlock_bh(&nf_conntrack_lock); |
| 1035 | |
| 1036 | free_conntrack_hash(old_hash, old_vmalloced, old_size); |
| 1037 | return 0; |
| 1038 | } |
| 1039 | |
| 1040 | module_param_call(hashsize, set_hashsize, param_get_uint, |
| 1041 | &nf_conntrack_htable_size, 0600); |
| 1042 | |
| 1043 | int __init nf_conntrack_init(void) |
| 1044 | { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1045 | int ret; |
| 1046 | |
| 1047 | /* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB |
| 1048 | * machine has 256 buckets. >= 1GB machines have 8192 buckets. */ |
| 1049 | if (!nf_conntrack_htable_size) { |
| 1050 | nf_conntrack_htable_size |
| 1051 | = (((num_physpages << PAGE_SHIFT) / 16384) |
| 1052 | / sizeof(struct list_head)); |
| 1053 | if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE)) |
| 1054 | nf_conntrack_htable_size = 8192; |
| 1055 | if (nf_conntrack_htable_size < 16) |
| 1056 | nf_conntrack_htable_size = 16; |
| 1057 | } |
Patrick McHardy | 8e5105a | 2007-07-07 22:27:33 -0700 | [diff] [blame^] | 1058 | nf_conntrack_hash = alloc_hashtable(&nf_conntrack_htable_size, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1059 | &nf_conntrack_vmalloc); |
| 1060 | if (!nf_conntrack_hash) { |
| 1061 | printk(KERN_ERR "Unable to create nf_conntrack_hash\n"); |
| 1062 | goto err_out; |
| 1063 | } |
| 1064 | |
Patrick McHardy | 8e5105a | 2007-07-07 22:27:33 -0700 | [diff] [blame^] | 1065 | nf_conntrack_max = 8 * nf_conntrack_htable_size; |
| 1066 | |
| 1067 | printk("nf_conntrack version %s (%u buckets, %d max)\n", |
| 1068 | NF_CONNTRACK_VERSION, nf_conntrack_htable_size, |
| 1069 | nf_conntrack_max); |
| 1070 | |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 1071 | nf_conntrack_cachep = kmem_cache_create("nf_conntrack", |
| 1072 | sizeof(struct nf_conn), |
| 1073 | 0, 0, NULL, NULL); |
| 1074 | if (!nf_conntrack_cachep) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1075 | printk(KERN_ERR "Unable to create nf_conn slab cache\n"); |
| 1076 | goto err_free_hash; |
| 1077 | } |
| 1078 | |
| 1079 | nf_conntrack_expect_cachep = kmem_cache_create("nf_conntrack_expect", |
| 1080 | sizeof(struct nf_conntrack_expect), |
| 1081 | 0, 0, NULL, NULL); |
| 1082 | if (!nf_conntrack_expect_cachep) { |
| 1083 | printk(KERN_ERR "Unable to create nf_expect slab cache\n"); |
| 1084 | goto err_free_conntrack_slab; |
| 1085 | } |
| 1086 | |
Patrick McHardy | ac5357e | 2007-03-14 16:38:25 -0700 | [diff] [blame] | 1087 | ret = nf_conntrack_proto_init(); |
Patrick McHardy | 933a41e | 2006-11-29 02:35:18 +0100 | [diff] [blame] | 1088 | if (ret < 0) |
| 1089 | goto out_free_expect_slab; |
| 1090 | |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 1091 | ret = nf_conntrack_helper_init(); |
| 1092 | if (ret < 0) |
| 1093 | goto out_fini_proto; |
| 1094 | |
Yasuyuki Kozakai | 7d3cdc6 | 2006-02-15 15:22:21 -0800 | [diff] [blame] | 1095 | /* For use by REJECT target */ |
Patrick McHardy | c3a47ab | 2007-02-12 11:09:19 -0800 | [diff] [blame] | 1096 | rcu_assign_pointer(ip_ct_attach, __nf_conntrack_attach); |
Yasuyuki Kozakai | de6e05c | 2007-03-23 11:17:27 -0700 | [diff] [blame] | 1097 | rcu_assign_pointer(nf_ct_destroy, destroy_conntrack); |
Yasuyuki Kozakai | 7d3cdc6 | 2006-02-15 15:22:21 -0800 | [diff] [blame] | 1098 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1099 | /* Set up fake conntrack: |
| 1100 | - to never be deleted, not in any hashes */ |
| 1101 | atomic_set(&nf_conntrack_untracked.ct_general.use, 1); |
| 1102 | /* - and look it like as a confirmed connection */ |
| 1103 | set_bit(IPS_CONFIRMED_BIT, &nf_conntrack_untracked.status); |
| 1104 | |
| 1105 | return ret; |
| 1106 | |
Yasuyuki Kozakai | ceceae1 | 2007-07-07 22:23:42 -0700 | [diff] [blame] | 1107 | out_fini_proto: |
| 1108 | nf_conntrack_proto_fini(); |
Patrick McHardy | 933a41e | 2006-11-29 02:35:18 +0100 | [diff] [blame] | 1109 | out_free_expect_slab: |
| 1110 | kmem_cache_destroy(nf_conntrack_expect_cachep); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1111 | err_free_conntrack_slab: |
Yasuyuki Kozakai | dacd2a1 | 2007-07-07 22:25:51 -0700 | [diff] [blame] | 1112 | kmem_cache_destroy(nf_conntrack_cachep); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1113 | err_free_hash: |
| 1114 | free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc, |
| 1115 | nf_conntrack_htable_size); |
| 1116 | err_out: |
| 1117 | return -ENOMEM; |
| 1118 | } |