| 1 | /* Expectation handling for nf_conntrack. */ |
| 2 | |
| 3 | /* (C) 1999-2001 Paul `Rusty' Russell |
| 4 | * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> |
| 5 | * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org> |
| 6 | * (c) 2005-2012 Patrick McHardy <kaber@trash.net> |
| 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 | |
| 13 | #include <linux/types.h> |
| 14 | #include <linux/netfilter.h> |
| 15 | #include <linux/skbuff.h> |
| 16 | #include <linux/proc_fs.h> |
| 17 | #include <linux/seq_file.h> |
| 18 | #include <linux/stddef.h> |
| 19 | #include <linux/slab.h> |
| 20 | #include <linux/err.h> |
| 21 | #include <linux/percpu.h> |
| 22 | #include <linux/kernel.h> |
| 23 | #include <linux/jhash.h> |
| 24 | #include <linux/moduleparam.h> |
| 25 | #include <linux/export.h> |
| 26 | #include <net/net_namespace.h> |
| 27 | |
| 28 | #include <net/netfilter/nf_conntrack.h> |
| 29 | #include <net/netfilter/nf_conntrack_core.h> |
| 30 | #include <net/netfilter/nf_conntrack_expect.h> |
| 31 | #include <net/netfilter/nf_conntrack_helper.h> |
| 32 | #include <net/netfilter/nf_conntrack_tuple.h> |
| 33 | #include <net/netfilter/nf_conntrack_zones.h> |
| 34 | |
| 35 | unsigned int nf_ct_expect_hsize __read_mostly; |
| 36 | EXPORT_SYMBOL_GPL(nf_ct_expect_hsize); |
| 37 | |
| 38 | unsigned int nf_ct_expect_max __read_mostly; |
| 39 | |
| 40 | static struct kmem_cache *nf_ct_expect_cachep __read_mostly; |
| 41 | |
| 42 | /* nf_conntrack_expect helper functions */ |
| 43 | void nf_ct_unlink_expect_report(struct nf_conntrack_expect *exp, |
| 44 | u32 portid, int report) |
| 45 | { |
| 46 | struct nf_conn_help *master_help = nfct_help(exp->master); |
| 47 | struct net *net = nf_ct_exp_net(exp); |
| 48 | |
| 49 | NF_CT_ASSERT(master_help); |
| 50 | NF_CT_ASSERT(!timer_pending(&exp->timeout)); |
| 51 | |
| 52 | hlist_del_rcu(&exp->hnode); |
| 53 | net->ct.expect_count--; |
| 54 | |
| 55 | hlist_del(&exp->lnode); |
| 56 | master_help->expecting[exp->class]--; |
| 57 | |
| 58 | nf_ct_expect_event_report(IPEXP_DESTROY, exp, portid, report); |
| 59 | nf_ct_expect_put(exp); |
| 60 | |
| 61 | NF_CT_STAT_INC(net, expect_delete); |
| 62 | } |
| 63 | EXPORT_SYMBOL_GPL(nf_ct_unlink_expect_report); |
| 64 | |
| 65 | static void nf_ct_expectation_timed_out(unsigned long ul_expect) |
| 66 | { |
| 67 | struct nf_conntrack_expect *exp = (void *)ul_expect; |
| 68 | |
| 69 | spin_lock_bh(&nf_conntrack_expect_lock); |
| 70 | nf_ct_unlink_expect(exp); |
| 71 | spin_unlock_bh(&nf_conntrack_expect_lock); |
| 72 | nf_ct_expect_put(exp); |
| 73 | } |
| 74 | |
| 75 | static unsigned int nf_ct_expect_dst_hash(const struct nf_conntrack_tuple *tuple) |
| 76 | { |
| 77 | unsigned int hash; |
| 78 | |
| 79 | if (unlikely(!nf_conntrack_hash_rnd)) { |
| 80 | init_nf_conntrack_hash_rnd(); |
| 81 | } |
| 82 | |
| 83 | hash = jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all), |
| 84 | (((tuple->dst.protonum ^ tuple->src.l3num) << 16) | |
| 85 | (__force __u16)tuple->dst.u.all) ^ nf_conntrack_hash_rnd); |
| 86 | return ((u64)hash * nf_ct_expect_hsize) >> 32; |
| 87 | } |
| 88 | |
| 89 | struct nf_conntrack_expect * |
| 90 | __nf_ct_expect_find(struct net *net, u16 zone, |
| 91 | const struct nf_conntrack_tuple *tuple) |
| 92 | { |
| 93 | struct nf_conntrack_expect *i; |
| 94 | unsigned int h; |
| 95 | |
| 96 | if (!net->ct.expect_count) |
| 97 | return NULL; |
| 98 | |
| 99 | h = nf_ct_expect_dst_hash(tuple); |
| 100 | hlist_for_each_entry_rcu(i, &net->ct.expect_hash[h], hnode) { |
| 101 | if (nf_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask) && |
| 102 | nf_ct_zone(i->master) == zone) |
| 103 | return i; |
| 104 | } |
| 105 | return NULL; |
| 106 | } |
| 107 | EXPORT_SYMBOL_GPL(__nf_ct_expect_find); |
| 108 | |
| 109 | /* Just find a expectation corresponding to a tuple. */ |
| 110 | struct nf_conntrack_expect * |
| 111 | nf_ct_expect_find_get(struct net *net, u16 zone, |
| 112 | const struct nf_conntrack_tuple *tuple) |
| 113 | { |
| 114 | struct nf_conntrack_expect *i; |
| 115 | |
| 116 | rcu_read_lock(); |
| 117 | i = __nf_ct_expect_find(net, zone, tuple); |
| 118 | if (i && !atomic_inc_not_zero(&i->use)) |
| 119 | i = NULL; |
| 120 | rcu_read_unlock(); |
| 121 | |
| 122 | return i; |
| 123 | } |
| 124 | EXPORT_SYMBOL_GPL(nf_ct_expect_find_get); |
| 125 | |
| 126 | /* If an expectation for this connection is found, it gets delete from |
| 127 | * global list then returned. */ |
| 128 | struct nf_conntrack_expect * |
| 129 | nf_ct_find_expectation(struct net *net, u16 zone, |
| 130 | const struct nf_conntrack_tuple *tuple) |
| 131 | { |
| 132 | struct nf_conntrack_expect *i, *exp = NULL; |
| 133 | unsigned int h; |
| 134 | |
| 135 | if (!net->ct.expect_count) |
| 136 | return NULL; |
| 137 | |
| 138 | h = nf_ct_expect_dst_hash(tuple); |
| 139 | hlist_for_each_entry(i, &net->ct.expect_hash[h], hnode) { |
| 140 | if (!(i->flags & NF_CT_EXPECT_INACTIVE) && |
| 141 | nf_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask) && |
| 142 | nf_ct_zone(i->master) == zone) { |
| 143 | exp = i; |
| 144 | break; |
| 145 | } |
| 146 | } |
| 147 | if (!exp) |
| 148 | return NULL; |
| 149 | |
| 150 | /* If master is not in hash table yet (ie. packet hasn't left |
| 151 | this machine yet), how can other end know about expected? |
| 152 | Hence these are not the droids you are looking for (if |
| 153 | master ct never got confirmed, we'd hold a reference to it |
| 154 | and weird things would happen to future packets). */ |
| 155 | if (!nf_ct_is_confirmed(exp->master)) |
| 156 | return NULL; |
| 157 | |
| 158 | /* Avoid race with other CPUs, that for exp->master ct, is |
| 159 | * about to invoke ->destroy(), or nf_ct_delete() via timeout |
| 160 | * or early_drop(). |
| 161 | * |
| 162 | * The atomic_inc_not_zero() check tells: If that fails, we |
| 163 | * know that the ct is being destroyed. If it succeeds, we |
| 164 | * can be sure the ct cannot disappear underneath. |
| 165 | */ |
| 166 | if (unlikely(nf_ct_is_dying(exp->master) || |
| 167 | !atomic_inc_not_zero(&exp->master->ct_general.use))) |
| 168 | return NULL; |
| 169 | |
| 170 | if (exp->flags & NF_CT_EXPECT_PERMANENT) { |
| 171 | atomic_inc(&exp->use); |
| 172 | return exp; |
| 173 | } else if (del_timer(&exp->timeout)) { |
| 174 | nf_ct_unlink_expect(exp); |
| 175 | return exp; |
| 176 | } |
| 177 | /* Undo exp->master refcnt increase, if del_timer() failed */ |
| 178 | nf_ct_put(exp->master); |
| 179 | |
| 180 | return NULL; |
| 181 | } |
| 182 | |
| 183 | /* delete all expectations for this conntrack */ |
| 184 | void nf_ct_remove_expectations(struct nf_conn *ct) |
| 185 | { |
| 186 | struct nf_conn_help *help = nfct_help(ct); |
| 187 | struct nf_conntrack_expect *exp; |
| 188 | struct hlist_node *next; |
| 189 | |
| 190 | /* Optimization: most connection never expect any others. */ |
| 191 | if (!help) |
| 192 | return; |
| 193 | |
| 194 | spin_lock_bh(&nf_conntrack_expect_lock); |
| 195 | hlist_for_each_entry_safe(exp, next, &help->expectations, lnode) { |
| 196 | if (del_timer(&exp->timeout)) { |
| 197 | nf_ct_unlink_expect(exp); |
| 198 | nf_ct_expect_put(exp); |
| 199 | } |
| 200 | } |
| 201 | spin_unlock_bh(&nf_conntrack_expect_lock); |
| 202 | } |
| 203 | EXPORT_SYMBOL_GPL(nf_ct_remove_expectations); |
| 204 | |
| 205 | /* Would two expected things clash? */ |
| 206 | static inline int expect_clash(const struct nf_conntrack_expect *a, |
| 207 | const struct nf_conntrack_expect *b) |
| 208 | { |
| 209 | /* Part covered by intersection of masks must be unequal, |
| 210 | otherwise they clash */ |
| 211 | struct nf_conntrack_tuple_mask intersect_mask; |
| 212 | int count; |
| 213 | |
| 214 | intersect_mask.src.u.all = a->mask.src.u.all & b->mask.src.u.all; |
| 215 | |
| 216 | for (count = 0; count < NF_CT_TUPLE_L3SIZE; count++){ |
| 217 | intersect_mask.src.u3.all[count] = |
| 218 | a->mask.src.u3.all[count] & b->mask.src.u3.all[count]; |
| 219 | } |
| 220 | |
| 221 | return nf_ct_tuple_mask_cmp(&a->tuple, &b->tuple, &intersect_mask); |
| 222 | } |
| 223 | |
| 224 | static inline int expect_matches(const struct nf_conntrack_expect *a, |
| 225 | const struct nf_conntrack_expect *b) |
| 226 | { |
| 227 | return a->master == b->master && a->class == b->class && |
| 228 | nf_ct_tuple_equal(&a->tuple, &b->tuple) && |
| 229 | nf_ct_tuple_mask_equal(&a->mask, &b->mask) && |
| 230 | nf_ct_zone(a->master) == nf_ct_zone(b->master); |
| 231 | } |
| 232 | |
| 233 | /* Generally a bad idea to call this: could have matched already. */ |
| 234 | void nf_ct_unexpect_related(struct nf_conntrack_expect *exp) |
| 235 | { |
| 236 | spin_lock_bh(&nf_conntrack_expect_lock); |
| 237 | if (del_timer(&exp->timeout)) { |
| 238 | nf_ct_unlink_expect(exp); |
| 239 | nf_ct_expect_put(exp); |
| 240 | } |
| 241 | spin_unlock_bh(&nf_conntrack_expect_lock); |
| 242 | } |
| 243 | EXPORT_SYMBOL_GPL(nf_ct_unexpect_related); |
| 244 | |
| 245 | /* We don't increase the master conntrack refcount for non-fulfilled |
| 246 | * conntracks. During the conntrack destruction, the expectations are |
| 247 | * always killed before the conntrack itself */ |
| 248 | struct nf_conntrack_expect *nf_ct_expect_alloc(struct nf_conn *me) |
| 249 | { |
| 250 | struct nf_conntrack_expect *new; |
| 251 | |
| 252 | new = kmem_cache_alloc(nf_ct_expect_cachep, GFP_ATOMIC); |
| 253 | if (!new) |
| 254 | return NULL; |
| 255 | |
| 256 | new->master = me; |
| 257 | atomic_set(&new->use, 1); |
| 258 | return new; |
| 259 | } |
| 260 | EXPORT_SYMBOL_GPL(nf_ct_expect_alloc); |
| 261 | |
| 262 | void nf_ct_expect_init(struct nf_conntrack_expect *exp, unsigned int class, |
| 263 | u_int8_t family, |
| 264 | const union nf_inet_addr *saddr, |
| 265 | const union nf_inet_addr *daddr, |
| 266 | u_int8_t proto, const __be16 *src, const __be16 *dst) |
| 267 | { |
| 268 | int len; |
| 269 | |
| 270 | if (family == AF_INET) |
| 271 | len = 4; |
| 272 | else |
| 273 | len = 16; |
| 274 | |
| 275 | exp->flags = 0; |
| 276 | exp->class = class; |
| 277 | exp->expectfn = NULL; |
| 278 | exp->helper = NULL; |
| 279 | exp->tuple.src.l3num = family; |
| 280 | exp->tuple.dst.protonum = proto; |
| 281 | |
| 282 | if (saddr) { |
| 283 | memcpy(&exp->tuple.src.u3, saddr, len); |
| 284 | if (sizeof(exp->tuple.src.u3) > len) |
| 285 | /* address needs to be cleared for nf_ct_tuple_equal */ |
| 286 | memset((void *)&exp->tuple.src.u3 + len, 0x00, |
| 287 | sizeof(exp->tuple.src.u3) - len); |
| 288 | memset(&exp->mask.src.u3, 0xFF, len); |
| 289 | if (sizeof(exp->mask.src.u3) > len) |
| 290 | memset((void *)&exp->mask.src.u3 + len, 0x00, |
| 291 | sizeof(exp->mask.src.u3) - len); |
| 292 | } else { |
| 293 | memset(&exp->tuple.src.u3, 0x00, sizeof(exp->tuple.src.u3)); |
| 294 | memset(&exp->mask.src.u3, 0x00, sizeof(exp->mask.src.u3)); |
| 295 | } |
| 296 | |
| 297 | if (src) { |
| 298 | exp->tuple.src.u.all = *src; |
| 299 | exp->mask.src.u.all = htons(0xFFFF); |
| 300 | } else { |
| 301 | exp->tuple.src.u.all = 0; |
| 302 | exp->mask.src.u.all = 0; |
| 303 | } |
| 304 | |
| 305 | memcpy(&exp->tuple.dst.u3, daddr, len); |
| 306 | if (sizeof(exp->tuple.dst.u3) > len) |
| 307 | /* address needs to be cleared for nf_ct_tuple_equal */ |
| 308 | memset((void *)&exp->tuple.dst.u3 + len, 0x00, |
| 309 | sizeof(exp->tuple.dst.u3) - len); |
| 310 | |
| 311 | exp->tuple.dst.u.all = *dst; |
| 312 | |
| 313 | #ifdef CONFIG_NF_NAT_NEEDED |
| 314 | memset(&exp->saved_addr, 0, sizeof(exp->saved_addr)); |
| 315 | memset(&exp->saved_proto, 0, sizeof(exp->saved_proto)); |
| 316 | #endif |
| 317 | } |
| 318 | EXPORT_SYMBOL_GPL(nf_ct_expect_init); |
| 319 | |
| 320 | static void nf_ct_expect_free_rcu(struct rcu_head *head) |
| 321 | { |
| 322 | struct nf_conntrack_expect *exp; |
| 323 | |
| 324 | exp = container_of(head, struct nf_conntrack_expect, rcu); |
| 325 | kmem_cache_free(nf_ct_expect_cachep, exp); |
| 326 | } |
| 327 | |
| 328 | void nf_ct_expect_put(struct nf_conntrack_expect *exp) |
| 329 | { |
| 330 | if (atomic_dec_and_test(&exp->use)) |
| 331 | call_rcu(&exp->rcu, nf_ct_expect_free_rcu); |
| 332 | } |
| 333 | EXPORT_SYMBOL_GPL(nf_ct_expect_put); |
| 334 | |
| 335 | static int nf_ct_expect_insert(struct nf_conntrack_expect *exp) |
| 336 | { |
| 337 | struct nf_conn_help *master_help = nfct_help(exp->master); |
| 338 | struct nf_conntrack_helper *helper; |
| 339 | struct net *net = nf_ct_exp_net(exp); |
| 340 | unsigned int h = nf_ct_expect_dst_hash(&exp->tuple); |
| 341 | |
| 342 | /* two references : one for hash insert, one for the timer */ |
| 343 | atomic_add(2, &exp->use); |
| 344 | |
| 345 | hlist_add_head(&exp->lnode, &master_help->expectations); |
| 346 | master_help->expecting[exp->class]++; |
| 347 | |
| 348 | hlist_add_head_rcu(&exp->hnode, &net->ct.expect_hash[h]); |
| 349 | net->ct.expect_count++; |
| 350 | |
| 351 | setup_timer(&exp->timeout, nf_ct_expectation_timed_out, |
| 352 | (unsigned long)exp); |
| 353 | helper = rcu_dereference_protected(master_help->helper, |
| 354 | lockdep_is_held(&nf_conntrack_expect_lock)); |
| 355 | if (helper) { |
| 356 | exp->timeout.expires = jiffies + |
| 357 | helper->expect_policy[exp->class].timeout * HZ; |
| 358 | } |
| 359 | add_timer(&exp->timeout); |
| 360 | |
| 361 | NF_CT_STAT_INC(net, expect_create); |
| 362 | return 0; |
| 363 | } |
| 364 | |
| 365 | /* Race with expectations being used means we could have none to find; OK. */ |
| 366 | static void evict_oldest_expect(struct nf_conn *master, |
| 367 | struct nf_conntrack_expect *new) |
| 368 | { |
| 369 | struct nf_conn_help *master_help = nfct_help(master); |
| 370 | struct nf_conntrack_expect *exp, *last = NULL; |
| 371 | |
| 372 | hlist_for_each_entry(exp, &master_help->expectations, lnode) { |
| 373 | if (exp->class == new->class) |
| 374 | last = exp; |
| 375 | } |
| 376 | |
| 377 | if (last && del_timer(&last->timeout)) { |
| 378 | nf_ct_unlink_expect(last); |
| 379 | nf_ct_expect_put(last); |
| 380 | } |
| 381 | } |
| 382 | |
| 383 | static inline int __nf_ct_expect_check(struct nf_conntrack_expect *expect) |
| 384 | { |
| 385 | const struct nf_conntrack_expect_policy *p; |
| 386 | struct nf_conntrack_expect *i; |
| 387 | struct nf_conn *master = expect->master; |
| 388 | struct nf_conn_help *master_help = nfct_help(master); |
| 389 | struct nf_conntrack_helper *helper; |
| 390 | struct net *net = nf_ct_exp_net(expect); |
| 391 | struct hlist_node *next; |
| 392 | unsigned int h; |
| 393 | int ret = 1; |
| 394 | |
| 395 | if (!master_help) { |
| 396 | ret = -ESHUTDOWN; |
| 397 | goto out; |
| 398 | } |
| 399 | h = nf_ct_expect_dst_hash(&expect->tuple); |
| 400 | hlist_for_each_entry_safe(i, next, &net->ct.expect_hash[h], hnode) { |
| 401 | if (expect_matches(i, expect)) { |
| 402 | if (del_timer(&i->timeout)) { |
| 403 | nf_ct_unlink_expect(i); |
| 404 | nf_ct_expect_put(i); |
| 405 | break; |
| 406 | } |
| 407 | } else if (expect_clash(i, expect)) { |
| 408 | ret = -EBUSY; |
| 409 | goto out; |
| 410 | } |
| 411 | } |
| 412 | /* Will be over limit? */ |
| 413 | helper = rcu_dereference_protected(master_help->helper, |
| 414 | lockdep_is_held(&nf_conntrack_expect_lock)); |
| 415 | if (helper) { |
| 416 | p = &helper->expect_policy[expect->class]; |
| 417 | if (p->max_expected && |
| 418 | master_help->expecting[expect->class] >= p->max_expected) { |
| 419 | evict_oldest_expect(master, expect); |
| 420 | if (master_help->expecting[expect->class] |
| 421 | >= p->max_expected) { |
| 422 | ret = -EMFILE; |
| 423 | goto out; |
| 424 | } |
| 425 | } |
| 426 | } |
| 427 | |
| 428 | if (net->ct.expect_count >= nf_ct_expect_max) { |
| 429 | net_warn_ratelimited("nf_conntrack: expectation table full\n"); |
| 430 | ret = -EMFILE; |
| 431 | } |
| 432 | out: |
| 433 | return ret; |
| 434 | } |
| 435 | |
| 436 | int nf_ct_expect_related_report(struct nf_conntrack_expect *expect, |
| 437 | u32 portid, int report) |
| 438 | { |
| 439 | int ret; |
| 440 | |
| 441 | spin_lock_bh(&nf_conntrack_expect_lock); |
| 442 | ret = __nf_ct_expect_check(expect); |
| 443 | if (ret <= 0) |
| 444 | goto out; |
| 445 | |
| 446 | ret = nf_ct_expect_insert(expect); |
| 447 | if (ret < 0) |
| 448 | goto out; |
| 449 | spin_unlock_bh(&nf_conntrack_expect_lock); |
| 450 | nf_ct_expect_event_report(IPEXP_NEW, expect, portid, report); |
| 451 | return ret; |
| 452 | out: |
| 453 | spin_unlock_bh(&nf_conntrack_expect_lock); |
| 454 | return ret; |
| 455 | } |
| 456 | EXPORT_SYMBOL_GPL(nf_ct_expect_related_report); |
| 457 | |
| 458 | #ifdef CONFIG_NF_CONNTRACK_PROCFS |
| 459 | struct ct_expect_iter_state { |
| 460 | struct seq_net_private p; |
| 461 | unsigned int bucket; |
| 462 | }; |
| 463 | |
| 464 | static struct hlist_node *ct_expect_get_first(struct seq_file *seq) |
| 465 | { |
| 466 | struct net *net = seq_file_net(seq); |
| 467 | struct ct_expect_iter_state *st = seq->private; |
| 468 | struct hlist_node *n; |
| 469 | |
| 470 | for (st->bucket = 0; st->bucket < nf_ct_expect_hsize; st->bucket++) { |
| 471 | n = rcu_dereference(hlist_first_rcu(&net->ct.expect_hash[st->bucket])); |
| 472 | if (n) |
| 473 | return n; |
| 474 | } |
| 475 | return NULL; |
| 476 | } |
| 477 | |
| 478 | static struct hlist_node *ct_expect_get_next(struct seq_file *seq, |
| 479 | struct hlist_node *head) |
| 480 | { |
| 481 | struct net *net = seq_file_net(seq); |
| 482 | struct ct_expect_iter_state *st = seq->private; |
| 483 | |
| 484 | head = rcu_dereference(hlist_next_rcu(head)); |
| 485 | while (head == NULL) { |
| 486 | if (++st->bucket >= nf_ct_expect_hsize) |
| 487 | return NULL; |
| 488 | head = rcu_dereference(hlist_first_rcu(&net->ct.expect_hash[st->bucket])); |
| 489 | } |
| 490 | return head; |
| 491 | } |
| 492 | |
| 493 | static struct hlist_node *ct_expect_get_idx(struct seq_file *seq, loff_t pos) |
| 494 | { |
| 495 | struct hlist_node *head = ct_expect_get_first(seq); |
| 496 | |
| 497 | if (head) |
| 498 | while (pos && (head = ct_expect_get_next(seq, head))) |
| 499 | pos--; |
| 500 | return pos ? NULL : head; |
| 501 | } |
| 502 | |
| 503 | static void *exp_seq_start(struct seq_file *seq, loff_t *pos) |
| 504 | __acquires(RCU) |
| 505 | { |
| 506 | rcu_read_lock(); |
| 507 | return ct_expect_get_idx(seq, *pos); |
| 508 | } |
| 509 | |
| 510 | static void *exp_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 511 | { |
| 512 | (*pos)++; |
| 513 | return ct_expect_get_next(seq, v); |
| 514 | } |
| 515 | |
| 516 | static void exp_seq_stop(struct seq_file *seq, void *v) |
| 517 | __releases(RCU) |
| 518 | { |
| 519 | rcu_read_unlock(); |
| 520 | } |
| 521 | |
| 522 | static int exp_seq_show(struct seq_file *s, void *v) |
| 523 | { |
| 524 | struct nf_conntrack_expect *expect; |
| 525 | struct nf_conntrack_helper *helper; |
| 526 | struct hlist_node *n = v; |
| 527 | char *delim = ""; |
| 528 | |
| 529 | expect = hlist_entry(n, struct nf_conntrack_expect, hnode); |
| 530 | |
| 531 | if (expect->timeout.function) |
| 532 | seq_printf(s, "%ld ", timer_pending(&expect->timeout) |
| 533 | ? (long)(expect->timeout.expires - jiffies)/HZ : 0); |
| 534 | else |
| 535 | seq_printf(s, "- "); |
| 536 | seq_printf(s, "l3proto = %u proto=%u ", |
| 537 | expect->tuple.src.l3num, |
| 538 | expect->tuple.dst.protonum); |
| 539 | print_tuple(s, &expect->tuple, |
| 540 | __nf_ct_l3proto_find(expect->tuple.src.l3num), |
| 541 | __nf_ct_l4proto_find(expect->tuple.src.l3num, |
| 542 | expect->tuple.dst.protonum)); |
| 543 | |
| 544 | if (expect->flags & NF_CT_EXPECT_PERMANENT) { |
| 545 | seq_printf(s, "PERMANENT"); |
| 546 | delim = ","; |
| 547 | } |
| 548 | if (expect->flags & NF_CT_EXPECT_INACTIVE) { |
| 549 | seq_printf(s, "%sINACTIVE", delim); |
| 550 | delim = ","; |
| 551 | } |
| 552 | if (expect->flags & NF_CT_EXPECT_USERSPACE) |
| 553 | seq_printf(s, "%sUSERSPACE", delim); |
| 554 | |
| 555 | helper = rcu_dereference(nfct_help(expect->master)->helper); |
| 556 | if (helper) { |
| 557 | seq_printf(s, "%s%s", expect->flags ? " " : "", helper->name); |
| 558 | if (helper->expect_policy[expect->class].name) |
| 559 | seq_printf(s, "/%s", |
| 560 | helper->expect_policy[expect->class].name); |
| 561 | } |
| 562 | |
| 563 | return seq_putc(s, '\n'); |
| 564 | } |
| 565 | |
| 566 | static const struct seq_operations exp_seq_ops = { |
| 567 | .start = exp_seq_start, |
| 568 | .next = exp_seq_next, |
| 569 | .stop = exp_seq_stop, |
| 570 | .show = exp_seq_show |
| 571 | }; |
| 572 | |
| 573 | static int exp_open(struct inode *inode, struct file *file) |
| 574 | { |
| 575 | return seq_open_net(inode, file, &exp_seq_ops, |
| 576 | sizeof(struct ct_expect_iter_state)); |
| 577 | } |
| 578 | |
| 579 | static const struct file_operations exp_file_ops = { |
| 580 | .owner = THIS_MODULE, |
| 581 | .open = exp_open, |
| 582 | .read = seq_read, |
| 583 | .llseek = seq_lseek, |
| 584 | .release = seq_release_net, |
| 585 | }; |
| 586 | #endif /* CONFIG_NF_CONNTRACK_PROCFS */ |
| 587 | |
| 588 | static int exp_proc_init(struct net *net) |
| 589 | { |
| 590 | #ifdef CONFIG_NF_CONNTRACK_PROCFS |
| 591 | struct proc_dir_entry *proc; |
| 592 | |
| 593 | proc = proc_create("nf_conntrack_expect", 0440, net->proc_net, |
| 594 | &exp_file_ops); |
| 595 | if (!proc) |
| 596 | return -ENOMEM; |
| 597 | #endif /* CONFIG_NF_CONNTRACK_PROCFS */ |
| 598 | return 0; |
| 599 | } |
| 600 | |
| 601 | static void exp_proc_remove(struct net *net) |
| 602 | { |
| 603 | #ifdef CONFIG_NF_CONNTRACK_PROCFS |
| 604 | remove_proc_entry("nf_conntrack_expect", net->proc_net); |
| 605 | #endif /* CONFIG_NF_CONNTRACK_PROCFS */ |
| 606 | } |
| 607 | |
| 608 | module_param_named(expect_hashsize, nf_ct_expect_hsize, uint, 0400); |
| 609 | |
| 610 | int nf_conntrack_expect_pernet_init(struct net *net) |
| 611 | { |
| 612 | int err = -ENOMEM; |
| 613 | |
| 614 | net->ct.expect_count = 0; |
| 615 | net->ct.expect_hash = nf_ct_alloc_hashtable(&nf_ct_expect_hsize, 0); |
| 616 | if (net->ct.expect_hash == NULL) |
| 617 | goto err1; |
| 618 | |
| 619 | err = exp_proc_init(net); |
| 620 | if (err < 0) |
| 621 | goto err2; |
| 622 | |
| 623 | return 0; |
| 624 | err2: |
| 625 | nf_ct_free_hashtable(net->ct.expect_hash, nf_ct_expect_hsize); |
| 626 | err1: |
| 627 | return err; |
| 628 | } |
| 629 | |
| 630 | void nf_conntrack_expect_pernet_fini(struct net *net) |
| 631 | { |
| 632 | exp_proc_remove(net); |
| 633 | nf_ct_free_hashtable(net->ct.expect_hash, nf_ct_expect_hsize); |
| 634 | } |
| 635 | |
| 636 | int nf_conntrack_expect_init(void) |
| 637 | { |
| 638 | if (!nf_ct_expect_hsize) { |
| 639 | nf_ct_expect_hsize = nf_conntrack_htable_size / 256; |
| 640 | if (!nf_ct_expect_hsize) |
| 641 | nf_ct_expect_hsize = 1; |
| 642 | } |
| 643 | nf_ct_expect_max = nf_ct_expect_hsize * 4; |
| 644 | nf_ct_expect_cachep = kmem_cache_create("nf_conntrack_expect", |
| 645 | sizeof(struct nf_conntrack_expect), |
| 646 | 0, 0, NULL); |
| 647 | if (!nf_ct_expect_cachep) |
| 648 | return -ENOMEM; |
| 649 | return 0; |
| 650 | } |
| 651 | |
| 652 | void nf_conntrack_expect_fini(void) |
| 653 | { |
| 654 | rcu_barrier(); /* Wait for call_rcu() before destroy */ |
| 655 | kmem_cache_destroy(nf_ct_expect_cachep); |
| 656 | } |