net/netfilter/nf_conntrack_standalone.c

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