1 /* (C) 1999-2001 Paul `Rusty' Russell 2 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> 3 * (C) 2005-2012 Patrick McHardy <kaber@trash.net> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/types.h> 11 #include <linux/netfilter.h> 12 #include <linux/slab.h> 13 #include <linux/module.h> 14 #include <linux/skbuff.h> 15 #include <linux/proc_fs.h> 16 #include <linux/seq_file.h> 17 #include <linux/percpu.h> 18 #include <linux/netdevice.h> 19 #include <linux/security.h> 20 #include <net/net_namespace.h> 21 #ifdef CONFIG_SYSCTL 22 #include <linux/sysctl.h> 23 #endif 24 25 #include <net/netfilter/nf_conntrack.h> 26 #include <net/netfilter/nf_conntrack_core.h> 27 #include <net/netfilter/nf_conntrack_l3proto.h> 28 #include <net/netfilter/nf_conntrack_l4proto.h> 29 #include <net/netfilter/nf_conntrack_expect.h> 30 #include <net/netfilter/nf_conntrack_helper.h> 31 #include <net/netfilter/nf_conntrack_acct.h> 32 #include <net/netfilter/nf_conntrack_zones.h> 33 #include <net/netfilter/nf_conntrack_timestamp.h> 34 #include <linux/rculist_nulls.h> 35 36 MODULE_LICENSE("GPL"); 37 38 #ifdef CONFIG_NF_CONNTRACK_PROCFS 39 int 40 print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple, 41 const struct nf_conntrack_l3proto *l3proto, 42 const struct nf_conntrack_l4proto *l4proto) 43 { 44 return l3proto->print_tuple(s, tuple) || l4proto->print_tuple(s, tuple); 45 } 46 EXPORT_SYMBOL_GPL(print_tuple); 47 48 struct ct_iter_state { 49 struct seq_net_private p; 50 unsigned int bucket; 51 u_int64_t time_now; 52 }; 53 54 static struct hlist_nulls_node *ct_get_first(struct seq_file *seq) 55 { 56 struct net *net = seq_file_net(seq); 57 struct ct_iter_state *st = seq->private; 58 struct hlist_nulls_node *n; 59 60 for (st->bucket = 0; 61 st->bucket < net->ct.htable_size; 62 st->bucket++) { 63 n = rcu_dereference(hlist_nulls_first_rcu(&net->ct.hash[st->bucket])); 64 if (!is_a_nulls(n)) 65 return n; 66 } 67 return NULL; 68 } 69 70 static struct hlist_nulls_node *ct_get_next(struct seq_file *seq, 71 struct hlist_nulls_node *head) 72 { 73 struct net *net = seq_file_net(seq); 74 struct ct_iter_state *st = seq->private; 75 76 head = rcu_dereference(hlist_nulls_next_rcu(head)); 77 while (is_a_nulls(head)) { 78 if (likely(get_nulls_value(head) == st->bucket)) { 79 if (++st->bucket >= net->ct.htable_size) 80 return NULL; 81 } 82 head = rcu_dereference( 83 hlist_nulls_first_rcu( 84 &net->ct.hash[st->bucket])); 85 } 86 return head; 87 } 88 89 static struct hlist_nulls_node *ct_get_idx(struct seq_file *seq, loff_t pos) 90 { 91 struct hlist_nulls_node *head = ct_get_first(seq); 92 93 if (head) 94 while (pos && (head = ct_get_next(seq, head))) 95 pos--; 96 return pos ? NULL : head; 97 } 98 99 static void *ct_seq_start(struct seq_file *seq, loff_t *pos) 100 __acquires(RCU) 101 { 102 struct ct_iter_state *st = seq->private; 103 104 st->time_now = ktime_to_ns(ktime_get_real()); 105 rcu_read_lock(); 106 return ct_get_idx(seq, *pos); 107 } 108 109 static void *ct_seq_next(struct seq_file *s, void *v, loff_t *pos) 110 { 111 (*pos)++; 112 return ct_get_next(s, v); 113 } 114 115 static void ct_seq_stop(struct seq_file *s, void *v) 116 __releases(RCU) 117 { 118 rcu_read_unlock(); 119 } 120 121 #ifdef CONFIG_NF_CONNTRACK_SECMARK 122 static int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct) 123 { 124 int ret; 125 u32 len; 126 char *secctx; 127 128 ret = security_secid_to_secctx(ct->secmark, &secctx, &len); 129 if (ret) 130 return 0; 131 132 ret = seq_printf(s, "secctx=%s ", secctx); 133 134 security_release_secctx(secctx, len); 135 return ret; 136 } 137 #else 138 static inline int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct) 139 { 140 return 0; 141 } 142 #endif 143 144 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP 145 static int ct_show_delta_time(struct seq_file *s, const struct nf_conn *ct) 146 { 147 struct ct_iter_state *st = s->private; 148 struct nf_conn_tstamp *tstamp; 149 s64 delta_time; 150 151 tstamp = nf_conn_tstamp_find(ct); 152 if (tstamp) { 153 delta_time = st->time_now - tstamp->start; 154 if (delta_time > 0) 155 delta_time = div_s64(delta_time, NSEC_PER_SEC); 156 else 157 delta_time = 0; 158 159 return seq_printf(s, "delta-time=%llu ", 160 (unsigned long long)delta_time); 161 } 162 return 0; 163 } 164 #else 165 static inline int 166 ct_show_delta_time(struct seq_file *s, const struct nf_conn *ct) 167 { 168 return 0; 169 } 170 #endif 171 172 /* return 0 on success, 1 in case of error */ 173 static int ct_seq_show(struct seq_file *s, void *v) 174 { 175 struct nf_conntrack_tuple_hash *hash = v; 176 struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(hash); 177 const struct nf_conntrack_l3proto *l3proto; 178 const struct nf_conntrack_l4proto *l4proto; 179 int ret = 0; 180 181 NF_CT_ASSERT(ct); 182 if (unlikely(!atomic_inc_not_zero(&ct->ct_general.use))) 183 return 0; 184 185 /* we only want to print DIR_ORIGINAL */ 186 if (NF_CT_DIRECTION(hash)) 187 goto release; 188 189 l3proto = __nf_ct_l3proto_find(nf_ct_l3num(ct)); 190 NF_CT_ASSERT(l3proto); 191 l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct)); 192 NF_CT_ASSERT(l4proto); 193 194 ret = -ENOSPC; 195 if (seq_printf(s, "%-8s %u %-8s %u %ld ", 196 l3proto->name, nf_ct_l3num(ct), 197 l4proto->name, nf_ct_protonum(ct), 198 timer_pending(&ct->timeout) 199 ? (long)(ct->timeout.expires - jiffies)/HZ : 0) != 0) 200 goto release; 201 202 if (l4proto->print_conntrack && l4proto->print_conntrack(s, ct)) 203 goto release; 204 205 if (print_tuple(s, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, 206 l3proto, l4proto)) 207 goto release; 208 209 if (seq_print_acct(s, ct, IP_CT_DIR_ORIGINAL)) 210 goto release; 211 212 if (!(test_bit(IPS_SEEN_REPLY_BIT, &ct->status))) 213 if (seq_printf(s, "[UNREPLIED] ")) 214 goto release; 215 216 if (print_tuple(s, &ct->tuplehash[IP_CT_DIR_REPLY].tuple, 217 l3proto, l4proto)) 218 goto release; 219 220 if (seq_print_acct(s, ct, IP_CT_DIR_REPLY)) 221 goto release; 222 223 if (test_bit(IPS_ASSURED_BIT, &ct->status)) 224 if (seq_printf(s, "[ASSURED] ")) 225 goto release; 226 227 #if defined(CONFIG_NF_CONNTRACK_MARK) 228 if (seq_printf(s, "mark=%u ", ct->mark)) 229 goto release; 230 #endif 231 232 if (ct_show_secctx(s, ct)) 233 goto release; 234 235 #ifdef CONFIG_NF_CONNTRACK_ZONES 236 if (seq_printf(s, "zone=%u ", nf_ct_zone(ct))) 237 goto release; 238 #endif 239 240 if (ct_show_delta_time(s, ct)) 241 goto release; 242 243 if (seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use))) 244 goto release; 245 246 ret = 0; 247 release: 248 nf_ct_put(ct); 249 return ret; 250 } 251 252 static const struct seq_operations ct_seq_ops = { 253 .start = ct_seq_start, 254 .next = ct_seq_next, 255 .stop = ct_seq_stop, 256 .show = ct_seq_show 257 }; 258 259 static int ct_open(struct inode *inode, struct file *file) 260 { 261 return seq_open_net(inode, file, &ct_seq_ops, 262 sizeof(struct ct_iter_state)); 263 } 264 265 static const struct file_operations ct_file_ops = { 266 .owner = THIS_MODULE, 267 .open = ct_open, 268 .read = seq_read, 269 .llseek = seq_lseek, 270 .release = seq_release_net, 271 }; 272 273 static void *ct_cpu_seq_start(struct seq_file *seq, loff_t *pos) 274 { 275 struct net *net = seq_file_net(seq); 276 int cpu; 277 278 if (*pos == 0) 279 return SEQ_START_TOKEN; 280 281 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { 282 if (!cpu_possible(cpu)) 283 continue; 284 *pos = cpu + 1; 285 return per_cpu_ptr(net->ct.stat, cpu); 286 } 287 288 return NULL; 289 } 290 291 static void *ct_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) 292 { 293 struct net *net = seq_file_net(seq); 294 int cpu; 295 296 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { 297 if (!cpu_possible(cpu)) 298 continue; 299 *pos = cpu + 1; 300 return per_cpu_ptr(net->ct.stat, cpu); 301 } 302 303 return NULL; 304 } 305 306 static void ct_cpu_seq_stop(struct seq_file *seq, void *v) 307 { 308 } 309 310 static int ct_cpu_seq_show(struct seq_file *seq, void *v) 311 { 312 struct net *net = seq_file_net(seq); 313 unsigned int nr_conntracks = atomic_read(&net->ct.count); 314 const struct ip_conntrack_stat *st = v; 315 316 if (v == SEQ_START_TOKEN) { 317 seq_printf(seq, "entries searched found new invalid ignore delete delete_list insert insert_failed drop early_drop icmp_error expect_new expect_create expect_delete search_restart\n"); 318 return 0; 319 } 320 321 seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x " 322 "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n", 323 nr_conntracks, 324 st->searched, 325 st->found, 326 st->new, 327 st->invalid, 328 st->ignore, 329 st->delete, 330 st->delete_list, 331 st->insert, 332 st->insert_failed, 333 st->drop, 334 st->early_drop, 335 st->error, 336 337 st->expect_new, 338 st->expect_create, 339 st->expect_delete, 340 st->search_restart 341 ); 342 return 0; 343 } 344 345 static const struct seq_operations ct_cpu_seq_ops = { 346 .start = ct_cpu_seq_start, 347 .next = ct_cpu_seq_next, 348 .stop = ct_cpu_seq_stop, 349 .show = ct_cpu_seq_show, 350 }; 351 352 static int ct_cpu_seq_open(struct inode *inode, struct file *file) 353 { 354 return seq_open_net(inode, file, &ct_cpu_seq_ops, 355 sizeof(struct seq_net_private)); 356 } 357 358 static const struct file_operations ct_cpu_seq_fops = { 359 .owner = THIS_MODULE, 360 .open = ct_cpu_seq_open, 361 .read = seq_read, 362 .llseek = seq_lseek, 363 .release = seq_release_net, 364 }; 365 366 static int nf_conntrack_standalone_init_proc(struct net *net) 367 { 368 struct proc_dir_entry *pde; 369 370 pde = proc_create("nf_conntrack", 0440, net->proc_net, &ct_file_ops); 371 if (!pde) 372 goto out_nf_conntrack; 373 374 pde = proc_create("nf_conntrack", S_IRUGO, net->proc_net_stat, 375 &ct_cpu_seq_fops); 376 if (!pde) 377 goto out_stat_nf_conntrack; 378 return 0; 379 380 out_stat_nf_conntrack: 381 remove_proc_entry("nf_conntrack", net->proc_net); 382 out_nf_conntrack: 383 return -ENOMEM; 384 } 385 386 static void nf_conntrack_standalone_fini_proc(struct net *net) 387 { 388 remove_proc_entry("nf_conntrack", net->proc_net_stat); 389 remove_proc_entry("nf_conntrack", net->proc_net); 390 } 391 #else 392 static int nf_conntrack_standalone_init_proc(struct net *net) 393 { 394 return 0; 395 } 396 397 static void nf_conntrack_standalone_fini_proc(struct net *net) 398 { 399 } 400 #endif /* CONFIG_NF_CONNTRACK_PROCFS */ 401 402 /* Sysctl support */ 403 404 #ifdef CONFIG_SYSCTL 405 /* Log invalid packets of a given protocol */ 406 static int log_invalid_proto_min = 0; 407 static int log_invalid_proto_max = 255; 408 409 static struct ctl_table_header *nf_ct_netfilter_header; 410 411 static ctl_table nf_ct_sysctl_table[] = { 412 { 413 .procname = "nf_conntrack_max", 414 .data = &nf_conntrack_max, 415 .maxlen = sizeof(int), 416 .mode = 0644, 417 .proc_handler = proc_dointvec, 418 }, 419 { 420 .procname = "nf_conntrack_count", 421 .data = &init_net.ct.count, 422 .maxlen = sizeof(int), 423 .mode = 0444, 424 .proc_handler = proc_dointvec, 425 }, 426 { 427 .procname = "nf_conntrack_buckets", 428 .data = &init_net.ct.htable_size, 429 .maxlen = sizeof(unsigned int), 430 .mode = 0444, 431 .proc_handler = proc_dointvec, 432 }, 433 { 434 .procname = "nf_conntrack_checksum", 435 .data = &init_net.ct.sysctl_checksum, 436 .maxlen = sizeof(unsigned int), 437 .mode = 0644, 438 .proc_handler = proc_dointvec, 439 }, 440 { 441 .procname = "nf_conntrack_log_invalid", 442 .data = &init_net.ct.sysctl_log_invalid, 443 .maxlen = sizeof(unsigned int), 444 .mode = 0644, 445 .proc_handler = proc_dointvec_minmax, 446 .extra1 = &log_invalid_proto_min, 447 .extra2 = &log_invalid_proto_max, 448 }, 449 { 450 .procname = "nf_conntrack_expect_max", 451 .data = &nf_ct_expect_max, 452 .maxlen = sizeof(int), 453 .mode = 0644, 454 .proc_handler = proc_dointvec, 455 }, 456 { } 457 }; 458 459 #define NET_NF_CONNTRACK_MAX 2089 460 461 static ctl_table nf_ct_netfilter_table[] = { 462 { 463 .procname = "nf_conntrack_max", 464 .data = &nf_conntrack_max, 465 .maxlen = sizeof(int), 466 .mode = 0644, 467 .proc_handler = proc_dointvec, 468 }, 469 { } 470 }; 471 472 static int nf_conntrack_standalone_init_sysctl(struct net *net) 473 { 474 struct ctl_table *table; 475 476 table = kmemdup(nf_ct_sysctl_table, sizeof(nf_ct_sysctl_table), 477 GFP_KERNEL); 478 if (!table) 479 goto out_kmemdup; 480 481 table[1].data = &net->ct.count; 482 table[2].data = &net->ct.htable_size; 483 table[3].data = &net->ct.sysctl_checksum; 484 table[4].data = &net->ct.sysctl_log_invalid; 485 486 /* Don't export sysctls to unprivileged users */ 487 if (net->user_ns != &init_user_ns) 488 table[0].procname = NULL; 489 490 net->ct.sysctl_header = register_net_sysctl(net, "net/netfilter", table); 491 if (!net->ct.sysctl_header) 492 goto out_unregister_netfilter; 493 494 return 0; 495 496 out_unregister_netfilter: 497 kfree(table); 498 out_kmemdup: 499 return -ENOMEM; 500 } 501 502 static void nf_conntrack_standalone_fini_sysctl(struct net *net) 503 { 504 struct ctl_table *table; 505 506 table = net->ct.sysctl_header->ctl_table_arg; 507 unregister_net_sysctl_table(net->ct.sysctl_header); 508 kfree(table); 509 } 510 #else 511 static int nf_conntrack_standalone_init_sysctl(struct net *net) 512 { 513 return 0; 514 } 515 516 static void nf_conntrack_standalone_fini_sysctl(struct net *net) 517 { 518 } 519 #endif /* CONFIG_SYSCTL */ 520 521 static int nf_conntrack_pernet_init(struct net *net) 522 { 523 int ret; 524 525 ret = nf_conntrack_init_net(net); 526 if (ret < 0) 527 goto out_init; 528 529 ret = nf_conntrack_standalone_init_proc(net); 530 if (ret < 0) 531 goto out_proc; 532 533 net->ct.sysctl_checksum = 1; 534 net->ct.sysctl_log_invalid = 0; 535 ret = nf_conntrack_standalone_init_sysctl(net); 536 if (ret < 0) 537 goto out_sysctl; 538 539 return 0; 540 541 out_sysctl: 542 nf_conntrack_standalone_fini_proc(net); 543 out_proc: 544 nf_conntrack_cleanup_net(net); 545 out_init: 546 return ret; 547 } 548 549 static void nf_conntrack_pernet_exit(struct list_head *net_exit_list) 550 { 551 struct net *net; 552 553 list_for_each_entry(net, net_exit_list, exit_list) { 554 nf_conntrack_standalone_fini_sysctl(net); 555 nf_conntrack_standalone_fini_proc(net); 556 } 557 nf_conntrack_cleanup_net_list(net_exit_list); 558 } 559 560 static struct pernet_operations nf_conntrack_net_ops = { 561 .init = nf_conntrack_pernet_init, 562 .exit_batch = nf_conntrack_pernet_exit, 563 }; 564 565 static int __init nf_conntrack_standalone_init(void) 566 { 567 int ret = nf_conntrack_init_start(); 568 if (ret < 0) 569 goto out_start; 570 571 #ifdef CONFIG_SYSCTL 572 nf_ct_netfilter_header = 573 register_net_sysctl(&init_net, "net", nf_ct_netfilter_table); 574 if (!nf_ct_netfilter_header) { 575 pr_err("nf_conntrack: can't register to sysctl.\n"); 576 ret = -ENOMEM; 577 goto out_sysctl; 578 } 579 #endif 580 581 ret = register_pernet_subsys(&nf_conntrack_net_ops); 582 if (ret < 0) 583 goto out_pernet; 584 585 nf_conntrack_init_end(); 586 return 0; 587 588 out_pernet: 589 #ifdef CONFIG_SYSCTL 590 unregister_net_sysctl_table(nf_ct_netfilter_header); 591 out_sysctl: 592 #endif 593 nf_conntrack_cleanup_end(); 594 out_start: 595 return ret; 596 } 597 598 static void __exit nf_conntrack_standalone_fini(void) 599 { 600 nf_conntrack_cleanup_start(); 601 unregister_pernet_subsys(&nf_conntrack_net_ops); 602 #ifdef CONFIG_SYSCTL 603 unregister_net_sysctl_table(nf_ct_netfilter_header); 604 #endif 605 nf_conntrack_cleanup_end(); 606 } 607 608 module_init(nf_conntrack_standalone_init); 609 module_exit(nf_conntrack_standalone_fini); 610 611 /* Some modules need us, but don't depend directly on any symbol. 612 They should call this. */ 613 void need_conntrack(void) 614 { 615 } 616 EXPORT_SYMBOL_GPL(need_conntrack); 617