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