net/netfilter/nf_conntrack_netlink.c

   1 /* Connection tracking via netlink socket. Allows for user space
   2  * protocol helpers and general trouble making from userspace.
   3  *
   4  * (C) 2001 by Jay Schulist <jschlst@samba.org>
   5  * (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
   6  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
   7  * (C) 2005-2008 by Pablo Neira Ayuso <pablo@netfilter.org>
   8  *
   9  * Initial connection tracking via netlink development funded and
  10  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
  11  *
  12  * Further development of this code funded by Astaro AG (http://www.astaro.com)
  13  *
  14  * This software may be used and distributed according to the terms
  15  * of the GNU General Public License, incorporated herein by reference.
  16  */
  17
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/rculist.h>
  22 #include <linux/types.h>
  23 #include <linux/timer.h>
  24 #include <linux/skbuff.h>
  25 #include <linux/errno.h>
  26 #include <linux/netlink.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/notifier.h>
  30
  31 #include <linux/netfilter.h>
  32 #include <net/netlink.h>
  33 #include <net/netfilter/nf_conntrack.h>
  34 #include <net/netfilter/nf_conntrack_core.h>
  35 #include <net/netfilter/nf_conntrack_expect.h>
  36 #include <net/netfilter/nf_conntrack_helper.h>
  37 #include <net/netfilter/nf_conntrack_l3proto.h>
  38 #include <net/netfilter/nf_conntrack_l4proto.h>
  39 #include <net/netfilter/nf_conntrack_tuple.h>
  40 #include <net/netfilter/nf_conntrack_acct.h>
  41 #ifdef CONFIG_NF_NAT_NEEDED
  42 #include <net/netfilter/nf_nat_core.h>
  43 #include <net/netfilter/nf_nat_protocol.h>
  44 #endif
  45
  46 #include <linux/netfilter/nfnetlink.h>
  47 #include <linux/netfilter/nfnetlink_conntrack.h>
  48
  49 MODULE_LICENSE("GPL");
  50
  51 static char __initdata version[] = "0.93";
  52
  53 static inline int
  54 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  55                             const struct nf_conntrack_tuple *tuple,
  56                             struct nf_conntrack_l4proto *l4proto)
  57 {
  58         int ret = 0;
  59         struct nlattr *nest_parms;
  60
  61         nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO | NLA_F_NESTED);
  62         if (!nest_parms)
  63                 goto nla_put_failure;
  64         NLA_PUT_U8(skb, CTA_PROTO_NUM, tuple->dst.protonum);
  65
  66         if (likely(l4proto->tuple_to_nlattr))
  67                 ret = l4proto->tuple_to_nlattr(skb, tuple);
  68
  69         nla_nest_end(skb, nest_parms);
  70
  71         return ret;
  72
  73 nla_put_failure:
  74         return -1;
  75 }
  76
  77 static inline int
  78 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  79                          const struct nf_conntrack_tuple *tuple,
  80                          struct nf_conntrack_l3proto *l3proto)
  81 {
  82         int ret = 0;
  83         struct nlattr *nest_parms;
  84
  85         nest_parms = nla_nest_start(skb, CTA_TUPLE_IP | NLA_F_NESTED);
  86         if (!nest_parms)
  87                 goto nla_put_failure;
  88
  89         if (likely(l3proto->tuple_to_nlattr))
  90                 ret = l3proto->tuple_to_nlattr(skb, tuple);
  91
  92         nla_nest_end(skb, nest_parms);
  93
  94         return ret;
  95
  96 nla_put_failure:
  97         return -1;
  98 }
  99
 100 static int
 101 ctnetlink_dump_tuples(struct sk_buff *skb,
 102                       const struct nf_conntrack_tuple *tuple)
 103 {
 104         int ret;
 105         struct nf_conntrack_l3proto *l3proto;
 106         struct nf_conntrack_l4proto *l4proto;
 107
 108         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 109         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 110         nf_ct_l3proto_put(l3proto);
 111
 112         if (unlikely(ret < 0))
 113                 return ret;
 114
 115         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 116         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
 117         nf_ct_l4proto_put(l4proto);
 118
 119         return ret;
 120 }
 121
 122 static inline int
 123 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 124 {
 125         NLA_PUT_BE32(skb, CTA_STATUS, htonl(ct->status));
 126         return 0;
 127
 128 nla_put_failure:
 129         return -1;
 130 }
 131
 132 static inline int
 133 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 134 {
 135         long timeout = (ct->timeout.expires - jiffies) / HZ;
 136
 137         if (timeout < 0)
 138                 timeout = 0;
 139
 140         NLA_PUT_BE32(skb, CTA_TIMEOUT, htonl(timeout));
 141         return 0;
 142
 143 nla_put_failure:
 144         return -1;
 145 }
 146
 147 static inline int
 148 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 149 {
 150         struct nf_conntrack_l4proto *l4proto;
 151         struct nlattr *nest_proto;
 152         int ret;
 153
 154         l4proto = nf_ct_l4proto_find_get(nf_ct_l3num(ct), nf_ct_protonum(ct));
 155         if (!l4proto->to_nlattr) {
 156                 nf_ct_l4proto_put(l4proto);
 157                 return 0;
 158         }
 159
 160         nest_proto = nla_nest_start(skb, CTA_PROTOINFO | NLA_F_NESTED);
 161         if (!nest_proto)
 162                 goto nla_put_failure;
 163
 164         ret = l4proto->to_nlattr(skb, nest_proto, ct);
 165
 166         nf_ct_l4proto_put(l4proto);
 167
 168         nla_nest_end(skb, nest_proto);
 169
 170         return ret;
 171
 172 nla_put_failure:
 173         nf_ct_l4proto_put(l4proto);
 174         return -1;
 175 }
 176
 177 static inline int
 178 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 179 {
 180         struct nlattr *nest_helper;
 181         const struct nf_conn_help *help = nfct_help(ct);
 182         struct nf_conntrack_helper *helper;
 183
 184         if (!help)
 185                 return 0;
 186
 187         rcu_read_lock();
 188         helper = rcu_dereference(help->helper);
 189         if (!helper)
 190                 goto out;
 191
 192         nest_helper = nla_nest_start(skb, CTA_HELP | NLA_F_NESTED);
 193         if (!nest_helper)
 194                 goto nla_put_failure;
 195         NLA_PUT_STRING(skb, CTA_HELP_NAME, helper->name);
 196
 197         if (helper->to_nlattr)
 198                 helper->to_nlattr(skb, ct);
 199
 200         nla_nest_end(skb, nest_helper);
 201 out:
 202         rcu_read_unlock();
 203         return 0;
 204
 205 nla_put_failure:
 206         rcu_read_unlock();
 207         return -1;
 208 }
 209
 210 static int
 211 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 212                         enum ip_conntrack_dir dir)
 213 {
 214         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 215         struct nlattr *nest_count;
 216         const struct nf_conn_counter *acct;
 217
 218         acct = nf_conn_acct_find(ct);
 219         if (!acct)
 220                 return 0;
 221
 222         nest_count = nla_nest_start(skb, type | NLA_F_NESTED);
 223         if (!nest_count)
 224                 goto nla_put_failure;
 225
 226         NLA_PUT_BE64(skb, CTA_COUNTERS_PACKETS,
 227                      cpu_to_be64(acct[dir].packets));
 228         NLA_PUT_BE64(skb, CTA_COUNTERS_BYTES,
 229                      cpu_to_be64(acct[dir].bytes));
 230
 231         nla_nest_end(skb, nest_count);
 232
 233         return 0;
 234
 235 nla_put_failure:
 236         return -1;
 237 }
 238
 239 #ifdef CONFIG_NF_CONNTRACK_MARK
 240 static inline int
 241 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 242 {
 243         NLA_PUT_BE32(skb, CTA_MARK, htonl(ct->mark));
 244         return 0;
 245
 246 nla_put_failure:
 247         return -1;
 248 }
 249 #else
 250 #define ctnetlink_dump_mark(a, b) (0)
 251 #endif
 252
 253 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 254 static inline int
 255 ctnetlink_dump_secmark(struct sk_buff *skb, const struct nf_conn *ct)
 256 {
 257         NLA_PUT_BE32(skb, CTA_SECMARK, htonl(ct->secmark));
 258         return 0;
 259
 260 nla_put_failure:
 261         return -1;
 262 }
 263 #else
 264 #define ctnetlink_dump_secmark(a, b) (0)
 265 #endif
 266
 267 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
 268
 269 static inline int
 270 ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
 271 {
 272         struct nlattr *nest_parms;
 273
 274         if (!(ct->status & IPS_EXPECTED))
 275                 return 0;
 276
 277         nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER | NLA_F_NESTED);
 278         if (!nest_parms)
 279                 goto nla_put_failure;
 280         if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
 281                 goto nla_put_failure;
 282         nla_nest_end(skb, nest_parms);
 283
 284         return 0;
 285
 286 nla_put_failure:
 287         return -1;
 288 }
 289
 290 #ifdef CONFIG_NF_NAT_NEEDED
 291 static int
 292 dump_nat_seq_adj(struct sk_buff *skb, const struct nf_nat_seq *natseq, int type)
 293 {
 294         struct nlattr *nest_parms;
 295
 296         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
 297         if (!nest_parms)
 298                 goto nla_put_failure;
 299
 300         NLA_PUT_BE32(skb, CTA_NAT_SEQ_CORRECTION_POS,
 301                      htonl(natseq->correction_pos));
 302         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_BEFORE,
 303                      htonl(natseq->offset_before));
 304         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_AFTER,
 305                      htonl(natseq->offset_after));
 306
 307         nla_nest_end(skb, nest_parms);
 308
 309         return 0;
 310
 311 nla_put_failure:
 312         return -1;
 313 }
 314
 315 static inline int
 316 ctnetlink_dump_nat_seq_adj(struct sk_buff *skb, const struct nf_conn *ct)
 317 {
 318         struct nf_nat_seq *natseq;
 319         struct nf_conn_nat *nat = nfct_nat(ct);
 320
 321         if (!(ct->status & IPS_SEQ_ADJUST) || !nat)
 322                 return 0;
 323
 324         natseq = &nat->seq[IP_CT_DIR_ORIGINAL];
 325         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_ORIG) == -1)
 326                 return -1;
 327
 328         natseq = &nat->seq[IP_CT_DIR_REPLY];
 329         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_REPLY) == -1)
 330                 return -1;
 331
 332         return 0;
 333 }
 334 #else
 335 #define ctnetlink_dump_nat_seq_adj(a, b) (0)
 336 #endif
 337
 338 static inline int
 339 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 340 {
 341         NLA_PUT_BE32(skb, CTA_ID, htonl((unsigned long)ct));
 342         return 0;
 343
 344 nla_put_failure:
 345         return -1;
 346 }
 347
 348 static inline int
 349 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 350 {
 351         NLA_PUT_BE32(skb, CTA_USE, htonl(atomic_read(&ct->ct_general.use)));
 352         return 0;
 353
 354 nla_put_failure:
 355         return -1;
 356 }
 357
 358 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 359
 360 static int
 361 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 362                     int event, int nowait,
 363                     const struct nf_conn *ct)
 364 {
 365         struct nlmsghdr *nlh;
 366         struct nfgenmsg *nfmsg;
 367         struct nlattr *nest_parms;
 368         unsigned char *b = skb_tail_pointer(skb);
 369
 370         event |= NFNL_SUBSYS_CTNETLINK << 8;
 371         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 372         nfmsg  = NLMSG_DATA(nlh);
 373
 374         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 375         nfmsg->nfgen_family = nf_ct_l3num(ct);
 376         nfmsg->version      = NFNETLINK_V0;
 377         nfmsg->res_id       = 0;
 378
 379         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
 380         if (!nest_parms)
 381                 goto nla_put_failure;
 382         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 383                 goto nla_put_failure;
 384         nla_nest_end(skb, nest_parms);
 385
 386         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
 387         if (!nest_parms)
 388                 goto nla_put_failure;
 389         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 390                 goto nla_put_failure;
 391         nla_nest_end(skb, nest_parms);
 392
 393         if (ctnetlink_dump_status(skb, ct) < 0 ||
 394             ctnetlink_dump_timeout(skb, ct) < 0 ||
 395             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 396             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 397             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 398             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 399             ctnetlink_dump_mark(skb, ct) < 0 ||
 400             ctnetlink_dump_secmark(skb, ct) < 0 ||
 401             ctnetlink_dump_id(skb, ct) < 0 ||
 402             ctnetlink_dump_use(skb, ct) < 0 ||
 403             ctnetlink_dump_master(skb, ct) < 0 ||
 404             ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
 405                 goto nla_put_failure;
 406
 407         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 408         return skb->len;
 409
 410 nlmsg_failure:
 411 nla_put_failure:
 412         nlmsg_trim(skb, b);
 413         return -1;
 414 }
 415
 416 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 417 static int ctnetlink_conntrack_event(struct notifier_block *this,
 418                                      unsigned long events, void *ptr)
 419 {
 420         struct nlmsghdr *nlh;
 421         struct nfgenmsg *nfmsg;
 422         struct nlattr *nest_parms;
 423         struct nf_conn *ct = (struct nf_conn *)ptr;
 424         struct sk_buff *skb;
 425         unsigned int type;
 426         sk_buff_data_t b;
 427         unsigned int flags = 0, group;
 428
 429         /* ignore our fake conntrack entry */
 430         if (ct == &nf_conntrack_untracked)
 431                 return NOTIFY_DONE;
 432
 433         if (events & IPCT_DESTROY) {
 434                 type = IPCTNL_MSG_CT_DELETE;
 435                 group = NFNLGRP_CONNTRACK_DESTROY;
 436         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 437                 type = IPCTNL_MSG_CT_NEW;
 438                 flags = NLM_F_CREATE|NLM_F_EXCL;
 439                 group = NFNLGRP_CONNTRACK_NEW;
 440         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 441                 type = IPCTNL_MSG_CT_NEW;
 442                 group = NFNLGRP_CONNTRACK_UPDATE;
 443         } else
 444                 return NOTIFY_DONE;
 445
 446         if (!nfnetlink_has_listeners(group))
 447                 return NOTIFY_DONE;
 448
 449         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 450         if (!skb)
 451                 return NOTIFY_DONE;
 452
 453         b = skb->tail;
 454
 455         type |= NFNL_SUBSYS_CTNETLINK << 8;
 456         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 457         nfmsg = NLMSG_DATA(nlh);
 458
 459         nlh->nlmsg_flags    = flags;
 460         nfmsg->nfgen_family = nf_ct_l3num(ct);
 461         nfmsg->version  = NFNETLINK_V0;
 462         nfmsg->res_id   = 0;
 463
 464         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
 465         if (!nest_parms)
 466                 goto nla_put_failure;
 467         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 468                 goto nla_put_failure;
 469         nla_nest_end(skb, nest_parms);
 470
 471         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
 472         if (!nest_parms)
 473                 goto nla_put_failure;
 474         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 475                 goto nla_put_failure;
 476         nla_nest_end(skb, nest_parms);
 477
 478         if (ctnetlink_dump_id(skb, ct) < 0)
 479                 goto nla_put_failure;
 480
 481         if (ctnetlink_dump_status(skb, ct) < 0)
 482                 goto nla_put_failure;
 483
 484         if (events & IPCT_DESTROY) {
 485                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 486                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 487                         goto nla_put_failure;
 488         } else {
 489                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 490                         goto nla_put_failure;
 491
 492                 if (events & IPCT_PROTOINFO
 493                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 494                         goto nla_put_failure;
 495
 496                 if ((events & IPCT_HELPER || nfct_help(ct))
 497                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 498                         goto nla_put_failure;
 499
 500 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 501                 if ((events & IPCT_SECMARK || ct->secmark)
 502                     && ctnetlink_dump_secmark(skb, ct) < 0)
 503                         goto nla_put_failure;
 504 #endif
 505
 506                 if (events & IPCT_RELATED &&
 507                     ctnetlink_dump_master(skb, ct) < 0)
 508                         goto nla_put_failure;
 509
 510                 if (events & IPCT_NATSEQADJ &&
 511                     ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
 512                         goto nla_put_failure;
 513         }
 514
 515 #ifdef CONFIG_NF_CONNTRACK_MARK
 516         if ((events & IPCT_MARK || ct->mark)
 517             && ctnetlink_dump_mark(skb, ct) < 0)
 518                 goto nla_put_failure;
 519 #endif
 520
 521         nlh->nlmsg_len = skb->tail - b;
 522         nfnetlink_send(skb, 0, group, 0);
 523         return NOTIFY_DONE;
 524
 525 nlmsg_failure:
 526 nla_put_failure:
 527         kfree_skb(skb);
 528         return NOTIFY_DONE;
 529 }
 530 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 531
 532 static int ctnetlink_done(struct netlink_callback *cb)
 533 {
 534         if (cb->args[1])
 535                 nf_ct_put((struct nf_conn *)cb->args[1]);
 536         return 0;
 537 }
 538
 539 static int
 540 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 541 {
 542         struct nf_conn *ct, *last;
 543         struct nf_conntrack_tuple_hash *h;
 544         struct hlist_node *n;
 545         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 546         u_int8_t l3proto = nfmsg->nfgen_family;
 547
 548         rcu_read_lock();
 549         last = (struct nf_conn *)cb->args[1];
 550         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
 551 restart:
 552                 hlist_for_each_entry_rcu(h, n, &nf_conntrack_hash[cb->args[0]],
 553                                          hnode) {
 554                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 555                                 continue;
 556                         ct = nf_ct_tuplehash_to_ctrack(h);
 557                         /* Dump entries of a given L3 protocol number.
 558                          * If it is not specified, ie. l3proto == 0,
 559                          * then dump everything. */
 560                         if (l3proto && nf_ct_l3num(ct) != l3proto)
 561                                 continue;
 562                         if (cb->args[1]) {
 563                                 if (ct != last)
 564                                         continue;
 565                                 cb->args[1] = 0;
 566                         }
 567                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 568                                                 cb->nlh->nlmsg_seq,
 569                                                 IPCTNL_MSG_CT_NEW,
 570                                                 1, ct) < 0) {
 571                                 if (!atomic_inc_not_zero(&ct->ct_general.use))
 572                                         continue;
 573                                 cb->args[1] = (unsigned long)ct;
 574                                 goto out;
 575                         }
 576
 577                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 578                                                 IPCTNL_MSG_CT_GET_CTRZERO) {
 579                                 struct nf_conn_counter *acct;
 580
 581                                 acct = nf_conn_acct_find(ct);
 582                                 if (acct)
 583                                         memset(acct, 0, sizeof(struct nf_conn_counter[IP_CT_DIR_MAX]));
 584                         }
 585                 }
 586                 if (cb->args[1]) {
 587                         cb->args[1] = 0;
 588                         goto restart;
 589                 }
 590         }
 591 out:
 592         rcu_read_unlock();
 593         if (last)
 594                 nf_ct_put(last);
 595
 596         return skb->len;
 597 }
 598
 599 static inline int
 600 ctnetlink_parse_tuple_ip(struct nlattr *attr, struct nf_conntrack_tuple *tuple)
 601 {
 602         struct nlattr *tb[CTA_IP_MAX+1];
 603         struct nf_conntrack_l3proto *l3proto;
 604         int ret = 0;
 605
 606         nla_parse_nested(tb, CTA_IP_MAX, attr, NULL);
 607
 608         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 609
 610         if (likely(l3proto->nlattr_to_tuple)) {
 611                 ret = nla_validate_nested(attr, CTA_IP_MAX,
 612                                           l3proto->nla_policy);
 613                 if (ret == 0)
 614                         ret = l3proto->nlattr_to_tuple(tb, tuple);
 615         }
 616
 617         nf_ct_l3proto_put(l3proto);
 618
 619         return ret;
 620 }
 621
 622 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
 623         [CTA_PROTO_NUM] = { .type = NLA_U8 },
 624 };
 625
 626 static inline int
 627 ctnetlink_parse_tuple_proto(struct nlattr *attr,
 628                             struct nf_conntrack_tuple *tuple)
 629 {
 630         struct nlattr *tb[CTA_PROTO_MAX+1];
 631         struct nf_conntrack_l4proto *l4proto;
 632         int ret = 0;
 633
 634         ret = nla_parse_nested(tb, CTA_PROTO_MAX, attr, proto_nla_policy);
 635         if (ret < 0)
 636                 return ret;
 637
 638         if (!tb[CTA_PROTO_NUM])
 639                 return -EINVAL;
 640         tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
 641
 642         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 643
 644         if (likely(l4proto->nlattr_to_tuple)) {
 645                 ret = nla_validate_nested(attr, CTA_PROTO_MAX,
 646                                           l4proto->nla_policy);
 647                 if (ret == 0)
 648                         ret = l4proto->nlattr_to_tuple(tb, tuple);
 649         }
 650
 651         nf_ct_l4proto_put(l4proto);
 652
 653         return ret;
 654 }
 655
 656 static int
 657 ctnetlink_parse_tuple(struct nlattr *cda[], struct nf_conntrack_tuple *tuple,
 658                       enum ctattr_tuple type, u_int8_t l3num)
 659 {
 660         struct nlattr *tb[CTA_TUPLE_MAX+1];
 661         int err;
 662
 663         memset(tuple, 0, sizeof(*tuple));
 664
 665         nla_parse_nested(tb, CTA_TUPLE_MAX, cda[type], NULL);
 666
 667         if (!tb[CTA_TUPLE_IP])
 668                 return -EINVAL;
 669
 670         tuple->src.l3num = l3num;
 671
 672         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple);
 673         if (err < 0)
 674                 return err;
 675
 676         if (!tb[CTA_TUPLE_PROTO])
 677                 return -EINVAL;
 678
 679         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple);
 680         if (err < 0)
 681                 return err;
 682
 683         /* orig and expect tuples get DIR_ORIGINAL */
 684         if (type == CTA_TUPLE_REPLY)
 685                 tuple->dst.dir = IP_CT_DIR_REPLY;
 686         else
 687                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 688
 689         return 0;
 690 }
 691
 692 #ifdef CONFIG_NF_NAT_NEEDED
 693 static const struct nla_policy protonat_nla_policy[CTA_PROTONAT_MAX+1] = {
 694         [CTA_PROTONAT_PORT_MIN] = { .type = NLA_U16 },
 695         [CTA_PROTONAT_PORT_MAX] = { .type = NLA_U16 },
 696 };
 697
 698 static int nfnetlink_parse_nat_proto(struct nlattr *attr,
 699                                      const struct nf_conn *ct,
 700                                      struct nf_nat_range *range)
 701 {
 702         struct nlattr *tb[CTA_PROTONAT_MAX+1];
 703         const struct nf_nat_protocol *npt;
 704         int err;
 705
 706         err = nla_parse_nested(tb, CTA_PROTONAT_MAX, attr, protonat_nla_policy);
 707         if (err < 0)
 708                 return err;
 709
 710         npt = nf_nat_proto_find_get(nf_ct_protonum(ct));
 711         if (npt->nlattr_to_range)
 712                 err = npt->nlattr_to_range(tb, range);
 713         nf_nat_proto_put(npt);
 714         return err;
 715 }
 716
 717 static const struct nla_policy nat_nla_policy[CTA_NAT_MAX+1] = {
 718         [CTA_NAT_MINIP]         = { .type = NLA_U32 },
 719         [CTA_NAT_MAXIP]         = { .type = NLA_U32 },
 720 };
 721
 722 static inline int
 723 nfnetlink_parse_nat(struct nlattr *nat,
 724                     const struct nf_conn *ct, struct nf_nat_range *range)
 725 {
 726         struct nlattr *tb[CTA_NAT_MAX+1];
 727         int err;
 728
 729         memset(range, 0, sizeof(*range));
 730
 731         err = nla_parse_nested(tb, CTA_NAT_MAX, nat, nat_nla_policy);
 732         if (err < 0)
 733                 return err;
 734
 735         if (tb[CTA_NAT_MINIP])
 736                 range->min_ip = nla_get_be32(tb[CTA_NAT_MINIP]);
 737
 738         if (!tb[CTA_NAT_MAXIP])
 739                 range->max_ip = range->min_ip;
 740         else
 741                 range->max_ip = nla_get_be32(tb[CTA_NAT_MAXIP]);
 742
 743         if (range->min_ip)
 744                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 745
 746         if (!tb[CTA_NAT_PROTO])
 747                 return 0;
 748
 749         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO], ct, range);
 750         if (err < 0)
 751                 return err;
 752
 753         return 0;
 754 }
 755 #endif
 756
 757 static inline int
 758 ctnetlink_parse_help(struct nlattr *attr, char **helper_name)
 759 {
 760         struct nlattr *tb[CTA_HELP_MAX+1];
 761
 762         nla_parse_nested(tb, CTA_HELP_MAX, attr, NULL);
 763
 764         if (!tb[CTA_HELP_NAME])
 765                 return -EINVAL;
 766
 767         *helper_name = nla_data(tb[CTA_HELP_NAME]);
 768
 769         return 0;
 770 }
 771
 772 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
 773         [CTA_STATUS]            = { .type = NLA_U32 },
 774         [CTA_TIMEOUT]           = { .type = NLA_U32 },
 775         [CTA_MARK]              = { .type = NLA_U32 },
 776         [CTA_USE]               = { .type = NLA_U32 },
 777         [CTA_ID]                = { .type = NLA_U32 },
 778 };
 779
 780 static int
 781 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 782                         struct nlmsghdr *nlh, struct nlattr *cda[])
 783 {
 784         struct nf_conntrack_tuple_hash *h;
 785         struct nf_conntrack_tuple tuple;
 786         struct nf_conn *ct;
 787         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 788         u_int8_t u3 = nfmsg->nfgen_family;
 789         int err = 0;
 790
 791         if (cda[CTA_TUPLE_ORIG])
 792                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 793         else if (cda[CTA_TUPLE_REPLY])
 794                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 795         else {
 796                 /* Flush the whole table */
 797                 nf_conntrack_flush();
 798                 return 0;
 799         }
 800
 801         if (err < 0)
 802                 return err;
 803
 804         h = nf_conntrack_find_get(&tuple);
 805         if (!h)
 806                 return -ENOENT;
 807
 808         ct = nf_ct_tuplehash_to_ctrack(h);
 809
 810         if (cda[CTA_ID]) {
 811                 u_int32_t id = ntohl(nla_get_be32(cda[CTA_ID]));
 812                 if (id != (u32)(unsigned long)ct) {
 813                         nf_ct_put(ct);
 814                         return -ENOENT;
 815                 }
 816         }
 817
 818         nf_ct_kill(ct);
 819         nf_ct_put(ct);
 820
 821         return 0;
 822 }
 823
 824 static int
 825 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 826                         struct nlmsghdr *nlh, struct nlattr *cda[])
 827 {
 828         struct nf_conntrack_tuple_hash *h;
 829         struct nf_conntrack_tuple tuple;
 830         struct nf_conn *ct;
 831         struct sk_buff *skb2 = NULL;
 832         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 833         u_int8_t u3 = nfmsg->nfgen_family;
 834         int err = 0;
 835
 836         if (nlh->nlmsg_flags & NLM_F_DUMP)
 837                 return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
 838                                           ctnetlink_done);
 839
 840         if (cda[CTA_TUPLE_ORIG])
 841                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 842         else if (cda[CTA_TUPLE_REPLY])
 843                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 844         else
 845                 return -EINVAL;
 846
 847         if (err < 0)
 848                 return err;
 849
 850         h = nf_conntrack_find_get(&tuple);
 851         if (!h)
 852                 return -ENOENT;
 853
 854         ct = nf_ct_tuplehash_to_ctrack(h);
 855
 856         err = -ENOMEM;
 857         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 858         if (!skb2) {
 859                 nf_ct_put(ct);
 860                 return -ENOMEM;
 861         }
 862
 863         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 864                                   IPCTNL_MSG_CT_NEW, 1, ct);
 865         nf_ct_put(ct);
 866         if (err <= 0)
 867                 goto free;
 868
 869         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 870         if (err < 0)
 871                 goto out;
 872
 873         return 0;
 874
 875 free:
 876         kfree_skb(skb2);
 877 out:
 878         return err;
 879 }
 880
 881 static int
 882 ctnetlink_change_status(struct nf_conn *ct, struct nlattr *cda[])
 883 {
 884         unsigned long d;
 885         unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
 886         d = ct->status ^ status;
 887
 888         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 889                 /* unchangeable */
 890                 return -EBUSY;
 891
 892         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 893                 /* SEEN_REPLY bit can only be set */
 894                 return -EBUSY;
 895
 896         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 897                 /* ASSURED bit can only be set */
 898                 return -EBUSY;
 899
 900         if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
 901 #ifndef CONFIG_NF_NAT_NEEDED
 902                 return -EOPNOTSUPP;
 903 #else
 904                 struct nf_nat_range range;
 905
 906                 if (cda[CTA_NAT_DST]) {
 907                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST], ct,
 908                                                 &range) < 0)
 909                                 return -EINVAL;
 910                         if (nf_nat_initialized(ct, IP_NAT_MANIP_DST))
 911                                 return -EEXIST;
 912                         nf_nat_setup_info(ct, &range, IP_NAT_MANIP_DST);
 913                 }
 914                 if (cda[CTA_NAT_SRC]) {
 915                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC], ct,
 916                                                 &range) < 0)
 917                                 return -EINVAL;
 918                         if (nf_nat_initialized(ct, IP_NAT_MANIP_SRC))
 919                                 return -EEXIST;
 920                         nf_nat_setup_info(ct, &range, IP_NAT_MANIP_SRC);
 921                 }
 922 #endif
 923         }
 924
 925         /* Be careful here, modifying NAT bits can screw up things,
 926          * so don't let users modify them directly if they don't pass
 927          * nf_nat_range. */
 928         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 929         return 0;
 930 }
 931
 932
 933 static inline int
 934 ctnetlink_change_helper(struct nf_conn *ct, struct nlattr *cda[])
 935 {
 936         struct nf_conntrack_helper *helper;
 937         struct nf_conn_help *help = nfct_help(ct);
 938         char *helpname;
 939         int err;
 940
 941         /* don't change helper of sibling connections */
 942         if (ct->master)
 943                 return -EBUSY;
 944
 945         err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
 946         if (err < 0)
 947                 return err;
 948
 949         if (!strcmp(helpname, "")) {
 950                 if (help && help->helper) {
 951                         /* we had a helper before ... */
 952                         nf_ct_remove_expectations(ct);
 953                         rcu_assign_pointer(help->helper, NULL);
 954                 }
 955
 956                 return 0;
 957         }
 958
 959         helper = __nf_conntrack_helper_find_byname(helpname);
 960         if (helper == NULL)
 961                 return -EOPNOTSUPP;
 962
 963         if (help) {
 964                 if (help->helper == helper)
 965                         return 0;
 966                 if (help->helper)
 967                         return -EBUSY;
 968                 /* need to zero data of old helper */
 969                 memset(&help->help, 0, sizeof(help->help));
 970         } else {
 971                 help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
 972                 if (help == NULL)
 973                         return -ENOMEM;
 974         }
 975
 976         rcu_assign_pointer(help->helper, helper);
 977
 978         return 0;
 979 }
 980
 981 static inline int
 982 ctnetlink_change_timeout(struct nf_conn *ct, struct nlattr *cda[])
 983 {
 984         u_int32_t timeout = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
 985
 986         if (!del_timer(&ct->timeout))
 987                 return -ETIME;
 988
 989         ct->timeout.expires = jiffies + timeout * HZ;
 990         add_timer(&ct->timeout);
 991
 992         return 0;
 993 }
 994
 995 static inline int
 996 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nlattr *cda[])
 997 {
 998         struct nlattr *tb[CTA_PROTOINFO_MAX+1], *attr = cda[CTA_PROTOINFO];
 999         struct nf_conntrack_l4proto *l4proto;
1000         int err = 0;
1001
1002         nla_parse_nested(tb, CTA_PROTOINFO_MAX, attr, NULL);
1003
1004         l4proto = nf_ct_l4proto_find_get(nf_ct_l3num(ct), nf_ct_protonum(ct));
1005         if (l4proto->from_nlattr)
1006                 err = l4proto->from_nlattr(tb, ct);
1007         nf_ct_l4proto_put(l4proto);
1008
1009         return err;
1010 }
1011
1012 #ifdef CONFIG_NF_NAT_NEEDED
1013 static inline int
1014 change_nat_seq_adj(struct nf_nat_seq *natseq, struct nlattr *attr)
1015 {
1016         struct nlattr *cda[CTA_NAT_SEQ_MAX+1];
1017
1018         nla_parse_nested(cda, CTA_NAT_SEQ_MAX, attr, NULL);
1019
1020         if (!cda[CTA_NAT_SEQ_CORRECTION_POS])
1021                 return -EINVAL;
1022
1023         natseq->correction_pos =
1024                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_CORRECTION_POS]));
1025
1026         if (!cda[CTA_NAT_SEQ_OFFSET_BEFORE])
1027                 return -EINVAL;
1028
1029         natseq->offset_before =
1030                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_BEFORE]));
1031
1032         if (!cda[CTA_NAT_SEQ_OFFSET_AFTER])
1033                 return -EINVAL;
1034
1035         natseq->offset_after =
1036                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_AFTER]));
1037
1038         return 0;
1039 }
1040
1041 static int
1042 ctnetlink_change_nat_seq_adj(struct nf_conn *ct, struct nlattr *cda[])
1043 {
1044         int ret = 0;
1045         struct nf_conn_nat *nat = nfct_nat(ct);
1046
1047         if (!nat)
1048                 return 0;
1049
1050         if (cda[CTA_NAT_SEQ_ADJ_ORIG]) {
1051                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_ORIGINAL],
1052                                          cda[CTA_NAT_SEQ_ADJ_ORIG]);
1053                 if (ret < 0)
1054                         return ret;
1055
1056                 ct->status |= IPS_SEQ_ADJUST;
1057         }
1058
1059         if (cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1060                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_REPLY],
1061                                          cda[CTA_NAT_SEQ_ADJ_REPLY]);
1062                 if (ret < 0)
1063                         return ret;
1064
1065                 ct->status |= IPS_SEQ_ADJUST;
1066         }
1067
1068         return 0;
1069 }
1070 #endif
1071
1072 static int
1073 ctnetlink_change_conntrack(struct nf_conn *ct, struct nlattr *cda[])
1074 {
1075         int err;
1076
1077         if (cda[CTA_HELP]) {
1078                 err = ctnetlink_change_helper(ct, cda);
1079                 if (err < 0)
1080                         return err;
1081         }
1082
1083         if (cda[CTA_TIMEOUT]) {
1084                 err = ctnetlink_change_timeout(ct, cda);
1085                 if (err < 0)
1086                         return err;
1087         }
1088
1089         if (cda[CTA_STATUS]) {
1090                 err = ctnetlink_change_status(ct, cda);
1091                 if (err < 0)
1092                         return err;
1093         }
1094
1095         if (cda[CTA_PROTOINFO]) {
1096                 err = ctnetlink_change_protoinfo(ct, cda);
1097                 if (err < 0)
1098                         return err;
1099         }
1100
1101 #if defined(CONFIG_NF_CONNTRACK_MARK)
1102         if (cda[CTA_MARK])
1103                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1104 #endif
1105
1106 #ifdef CONFIG_NF_NAT_NEEDED
1107         if (cda[CTA_NAT_SEQ_ADJ_ORIG] || cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1108                 err = ctnetlink_change_nat_seq_adj(ct, cda);
1109                 if (err < 0)
1110                         return err;
1111         }
1112 #endif
1113
1114         return 0;
1115 }
1116
1117 static int
1118 ctnetlink_create_conntrack(struct nlattr *cda[],
1119                            struct nf_conntrack_tuple *otuple,
1120                            struct nf_conntrack_tuple *rtuple,
1121                            struct nf_conn *master_ct)
1122 {
1123         struct nf_conn *ct;
1124         int err = -EINVAL;
1125         struct nf_conn_help *help;
1126         struct nf_conntrack_helper *helper;
1127
1128         ct = nf_conntrack_alloc(otuple, rtuple, GFP_KERNEL);
1129         if (ct == NULL || IS_ERR(ct))
1130                 return -ENOMEM;
1131
1132         if (!cda[CTA_TIMEOUT])
1133                 goto err;
1134         ct->timeout.expires = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
1135
1136         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1137         ct->status |= IPS_CONFIRMED;
1138
1139         rcu_read_lock();
1140         helper = __nf_ct_helper_find(rtuple);
1141         if (helper) {
1142                 help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
1143                 if (help == NULL) {
1144                         rcu_read_unlock();
1145                         err = -ENOMEM;
1146                         goto err;
1147                 }
1148                 /* not in hash table yet so not strictly necessary */
1149                 rcu_assign_pointer(help->helper, helper);
1150         }
1151
1152         if (cda[CTA_STATUS]) {
1153                 err = ctnetlink_change_status(ct, cda);
1154                 if (err < 0) {
1155                         rcu_read_unlock();
1156                         goto err;
1157                 }
1158         }
1159
1160         if (cda[CTA_PROTOINFO]) {
1161                 err = ctnetlink_change_protoinfo(ct, cda);
1162                 if (err < 0) {
1163                         rcu_read_unlock();
1164                         goto err;
1165                 }
1166         }
1167
1168         nf_ct_acct_ext_add(ct, GFP_KERNEL);
1169
1170 #if defined(CONFIG_NF_CONNTRACK_MARK)
1171         if (cda[CTA_MARK])
1172                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1173 #endif
1174
1175         /* setup master conntrack: this is a confirmed expectation */
1176         if (master_ct) {
1177                 __set_bit(IPS_EXPECTED_BIT, &ct->status);
1178                 ct->master = master_ct;
1179         }
1180
1181         add_timer(&ct->timeout);
1182         nf_conntrack_hash_insert(ct);
1183         rcu_read_unlock();
1184
1185         return 0;
1186
1187 err:
1188         nf_conntrack_free(ct);
1189         return err;
1190 }
1191
1192 static int
1193 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1194                         struct nlmsghdr *nlh, struct nlattr *cda[])
1195 {
1196         struct nf_conntrack_tuple otuple, rtuple;
1197         struct nf_conntrack_tuple_hash *h = NULL;
1198         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1199         u_int8_t u3 = nfmsg->nfgen_family;
1200         int err = 0;
1201
1202         if (cda[CTA_TUPLE_ORIG]) {
1203                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1204                 if (err < 0)
1205                         return err;
1206         }
1207
1208         if (cda[CTA_TUPLE_REPLY]) {
1209                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1210                 if (err < 0)
1211                         return err;
1212         }
1213
1214         spin_lock_bh(&nf_conntrack_lock);
1215         if (cda[CTA_TUPLE_ORIG])
1216                 h = __nf_conntrack_find(&otuple);
1217         else if (cda[CTA_TUPLE_REPLY])
1218                 h = __nf_conntrack_find(&rtuple);
1219
1220         if (h == NULL) {
1221                 struct nf_conntrack_tuple master;
1222                 struct nf_conntrack_tuple_hash *master_h = NULL;
1223                 struct nf_conn *master_ct = NULL;
1224
1225                 if (cda[CTA_TUPLE_MASTER]) {
1226                         err = ctnetlink_parse_tuple(cda,
1227                                                     &master,
1228                                                     CTA_TUPLE_MASTER,
1229                                                     u3);
1230                         if (err < 0)
1231                                 goto out_unlock;
1232
1233                         master_h = __nf_conntrack_find(&master);
1234                         if (master_h == NULL) {
1235                                 err = -ENOENT;
1236                                 goto out_unlock;
1237                         }
1238                         master_ct = nf_ct_tuplehash_to_ctrack(master_h);
1239                         atomic_inc(&master_ct->ct_general.use);
1240                 }
1241
1242                 spin_unlock_bh(&nf_conntrack_lock);
1243                 err = -ENOENT;
1244                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1245                         err = ctnetlink_create_conntrack(cda,
1246                                                          &otuple,
1247                                                          &rtuple,
1248                                                          master_ct);
1249                 if (err < 0 && master_ct)
1250                         nf_ct_put(master_ct);
1251
1252                 return err;
1253         }
1254         /* implicit 'else' */
1255
1256         /* We manipulate the conntrack inside the global conntrack table lock,
1257          * so there's no need to increase the refcount */
1258         err = -EEXIST;
1259         if (!(nlh->nlmsg_flags & NLM_F_EXCL)) {
1260                 /* we only allow nat config for new conntracks */
1261                 if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
1262                         err = -EOPNOTSUPP;
1263                         goto out_unlock;
1264                 }
1265                 /* can't link an existing conntrack to a master */
1266                 if (cda[CTA_TUPLE_MASTER]) {
1267                         err = -EOPNOTSUPP;
1268                         goto out_unlock;
1269                 }
1270                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h),
1271                                                  cda);
1272         }
1273
1274 out_unlock:
1275         spin_unlock_bh(&nf_conntrack_lock);
1276         return err;
1277 }
1278
1279 /***********************************************************************
1280  * EXPECT
1281  ***********************************************************************/
1282
1283 static inline int
1284 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1285                          const struct nf_conntrack_tuple *tuple,
1286                          enum ctattr_expect type)
1287 {
1288         struct nlattr *nest_parms;
1289
1290         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
1291         if (!nest_parms)
1292                 goto nla_put_failure;
1293         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1294                 goto nla_put_failure;
1295         nla_nest_end(skb, nest_parms);
1296
1297         return 0;
1298
1299 nla_put_failure:
1300         return -1;
1301 }
1302
1303 static inline int
1304 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1305                         const struct nf_conntrack_tuple *tuple,
1306                         const struct nf_conntrack_tuple_mask *mask)
1307 {
1308         int ret;
1309         struct nf_conntrack_l3proto *l3proto;
1310         struct nf_conntrack_l4proto *l4proto;
1311         struct nf_conntrack_tuple m;
1312         struct nlattr *nest_parms;
1313
1314         memset(&m, 0xFF, sizeof(m));
1315         m.src.u.all = mask->src.u.all;
1316         memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
1317
1318         nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK | NLA_F_NESTED);
1319         if (!nest_parms)
1320                 goto nla_put_failure;
1321
1322         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1323         ret = ctnetlink_dump_tuples_ip(skb, &m, l3proto);
1324         nf_ct_l3proto_put(l3proto);
1325
1326         if (unlikely(ret < 0))
1327                 goto nla_put_failure;
1328
1329         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1330         ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
1331         nf_ct_l4proto_put(l4proto);
1332         if (unlikely(ret < 0))
1333                 goto nla_put_failure;
1334
1335         nla_nest_end(skb, nest_parms);
1336
1337         return 0;
1338
1339 nla_put_failure:
1340         return -1;
1341 }
1342
1343 static int
1344 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1345                           const struct nf_conntrack_expect *exp)
1346 {
1347         struct nf_conn *master = exp->master;
1348         long timeout = (exp->timeout.expires - jiffies) / HZ;
1349
1350         if (timeout < 0)
1351                 timeout = 0;
1352
1353         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1354                 goto nla_put_failure;
1355         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1356                 goto nla_put_failure;
1357         if (ctnetlink_exp_dump_tuple(skb,
1358                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1359                                  CTA_EXPECT_MASTER) < 0)
1360                 goto nla_put_failure;
1361
1362         NLA_PUT_BE32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout));
1363         NLA_PUT_BE32(skb, CTA_EXPECT_ID, htonl((unsigned long)exp));
1364
1365         return 0;
1366
1367 nla_put_failure:
1368         return -1;
1369 }
1370
1371 static int
1372 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1373                     int event,
1374                     int nowait,
1375                     const struct nf_conntrack_expect *exp)
1376 {
1377         struct nlmsghdr *nlh;
1378         struct nfgenmsg *nfmsg;
1379         unsigned char *b = skb_tail_pointer(skb);
1380
1381         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1382         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1383         nfmsg  = NLMSG_DATA(nlh);
1384
1385         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1386         nfmsg->nfgen_family = exp->tuple.src.l3num;
1387         nfmsg->version      = NFNETLINK_V0;
1388         nfmsg->res_id       = 0;
1389
1390         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1391                 goto nla_put_failure;
1392
1393         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1394         return skb->len;
1395
1396 nlmsg_failure:
1397 nla_put_failure:
1398         nlmsg_trim(skb, b);
1399         return -1;
1400 }
1401
1402 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1403 static int ctnetlink_expect_event(struct notifier_block *this,
1404                                   unsigned long events, void *ptr)
1405 {
1406         struct nlmsghdr *nlh;
1407         struct nfgenmsg *nfmsg;
1408         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1409         struct sk_buff *skb;
1410         unsigned int type;
1411         sk_buff_data_t b;
1412         int flags = 0;
1413
1414         if (events & IPEXP_NEW) {
1415                 type = IPCTNL_MSG_EXP_NEW;
1416                 flags = NLM_F_CREATE|NLM_F_EXCL;
1417         } else
1418                 return NOTIFY_DONE;
1419
1420         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1421                 return NOTIFY_DONE;
1422
1423         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1424         if (!skb)
1425                 return NOTIFY_DONE;
1426
1427         b = skb->tail;
1428
1429         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1430         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1431         nfmsg = NLMSG_DATA(nlh);
1432
1433         nlh->nlmsg_flags    = flags;
1434         nfmsg->nfgen_family = exp->tuple.src.l3num;
1435         nfmsg->version      = NFNETLINK_V0;
1436         nfmsg->res_id       = 0;
1437
1438         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1439                 goto nla_put_failure;
1440
1441         nlh->nlmsg_len = skb->tail - b;
1442         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1443         return NOTIFY_DONE;
1444
1445 nlmsg_failure:
1446 nla_put_failure:
1447         kfree_skb(skb);
1448         return NOTIFY_DONE;
1449 }
1450 #endif
1451 static int ctnetlink_exp_done(struct netlink_callback *cb)
1452 {
1453         if (cb->args[1])
1454                 nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
1455         return 0;
1456 }
1457
1458 static int
1459 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1460 {
1461         struct nf_conntrack_expect *exp, *last;
1462         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1463         struct hlist_node *n;
1464         u_int8_t l3proto = nfmsg->nfgen_family;
1465
1466         rcu_read_lock();
1467         last = (struct nf_conntrack_expect *)cb->args[1];
1468         for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
1469 restart:
1470                 hlist_for_each_entry(exp, n, &nf_ct_expect_hash[cb->args[0]],
1471                                      hnode) {
1472                         if (l3proto && exp->tuple.src.l3num != l3proto)
1473                                 continue;
1474                         if (cb->args[1]) {
1475                                 if (exp != last)
1476                                         continue;
1477                                 cb->args[1] = 0;
1478                         }
1479                         if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1480                                                     cb->nlh->nlmsg_seq,
1481                                                     IPCTNL_MSG_EXP_NEW,
1482                                                     1, exp) < 0) {
1483                                 if (!atomic_inc_not_zero(&exp->use))
1484                                         continue;
1485                                 cb->args[1] = (unsigned long)exp;
1486                                 goto out;
1487                         }
1488                 }
1489                 if (cb->args[1]) {
1490                         cb->args[1] = 0;
1491                         goto restart;
1492                 }
1493         }
1494 out:
1495         rcu_read_unlock();
1496         if (last)
1497                 nf_ct_expect_put(last);
1498
1499         return skb->len;
1500 }
1501
1502 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
1503         [CTA_EXPECT_TIMEOUT]    = { .type = NLA_U32 },
1504         [CTA_EXPECT_ID]         = { .type = NLA_U32 },
1505 };
1506
1507 static int
1508 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1509                      struct nlmsghdr *nlh, struct nlattr *cda[])
1510 {
1511         struct nf_conntrack_tuple tuple;
1512         struct nf_conntrack_expect *exp;
1513         struct sk_buff *skb2;
1514         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1515         u_int8_t u3 = nfmsg->nfgen_family;
1516         int err = 0;
1517
1518         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1519                 return netlink_dump_start(ctnl, skb, nlh,
1520                                           ctnetlink_exp_dump_table,
1521                                           ctnetlink_exp_done);
1522         }
1523
1524         if (cda[CTA_EXPECT_MASTER])
1525                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1526         else
1527                 return -EINVAL;
1528
1529         if (err < 0)
1530                 return err;
1531
1532         exp = nf_ct_expect_find_get(&tuple);
1533         if (!exp)
1534                 return -ENOENT;
1535
1536         if (cda[CTA_EXPECT_ID]) {
1537                 __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1538                 if (ntohl(id) != (u32)(unsigned long)exp) {
1539                         nf_ct_expect_put(exp);
1540                         return -ENOENT;
1541                 }
1542         }
1543
1544         err = -ENOMEM;
1545         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1546         if (!skb2)
1547                 goto out;
1548
1549         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1550                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1551                                       1, exp);
1552         if (err <= 0)
1553                 goto free;
1554
1555         nf_ct_expect_put(exp);
1556
1557         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1558
1559 free:
1560         kfree_skb(skb2);
1561 out:
1562         nf_ct_expect_put(exp);
1563         return err;
1564 }
1565
1566 static int
1567 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1568                      struct nlmsghdr *nlh, struct nlattr *cda[])
1569 {
1570         struct nf_conntrack_expect *exp;
1571         struct nf_conntrack_tuple tuple;
1572         struct nf_conntrack_helper *h;
1573         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1574         struct hlist_node *n, *next;
1575         u_int8_t u3 = nfmsg->nfgen_family;
1576         unsigned int i;
1577         int err;
1578
1579         if (cda[CTA_EXPECT_TUPLE]) {
1580                 /* delete a single expect by tuple */
1581                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1582                 if (err < 0)
1583                         return err;
1584
1585                 /* bump usage count to 2 */
1586                 exp = nf_ct_expect_find_get(&tuple);
1587                 if (!exp)
1588                         return -ENOENT;
1589
1590                 if (cda[CTA_EXPECT_ID]) {
1591                         __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1592                         if (ntohl(id) != (u32)(unsigned long)exp) {
1593                                 nf_ct_expect_put(exp);
1594                                 return -ENOENT;
1595                         }
1596                 }
1597
1598                 /* after list removal, usage count == 1 */
1599                 nf_ct_unexpect_related(exp);
1600                 /* have to put what we 'get' above.
1601                  * after this line usage count == 0 */
1602                 nf_ct_expect_put(exp);
1603         } else if (cda[CTA_EXPECT_HELP_NAME]) {
1604                 char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
1605                 struct nf_conn_help *m_help;
1606
1607                 /* delete all expectations for this helper */
1608                 spin_lock_bh(&nf_conntrack_lock);
1609                 h = __nf_conntrack_helper_find_byname(name);
1610                 if (!h) {
1611                         spin_unlock_bh(&nf_conntrack_lock);
1612                         return -EOPNOTSUPP;
1613                 }
1614                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1615                         hlist_for_each_entry_safe(exp, n, next,
1616                                                   &nf_ct_expect_hash[i],
1617                                                   hnode) {
1618                                 m_help = nfct_help(exp->master);
1619                                 if (m_help->helper == h
1620                                     && del_timer(&exp->timeout)) {
1621                                         nf_ct_unlink_expect(exp);
1622                                         nf_ct_expect_put(exp);
1623                                 }
1624                         }
1625                 }
1626                 spin_unlock_bh(&nf_conntrack_lock);
1627         } else {
1628                 /* This basically means we have to flush everything*/
1629                 spin_lock_bh(&nf_conntrack_lock);
1630                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1631                         hlist_for_each_entry_safe(exp, n, next,
1632                                                   &nf_ct_expect_hash[i],
1633                                                   hnode) {
1634                                 if (del_timer(&exp->timeout)) {
1635                                         nf_ct_unlink_expect(exp);
1636                                         nf_ct_expect_put(exp);
1637                                 }
1638                         }
1639                 }
1640                 spin_unlock_bh(&nf_conntrack_lock);
1641         }
1642
1643         return 0;
1644 }
1645 static int
1646 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nlattr *cda[])
1647 {
1648         return -EOPNOTSUPP;
1649 }
1650
1651 static int
1652 ctnetlink_create_expect(struct nlattr *cda[], u_int8_t u3)
1653 {
1654         struct nf_conntrack_tuple tuple, mask, master_tuple;
1655         struct nf_conntrack_tuple_hash *h = NULL;
1656         struct nf_conntrack_expect *exp;
1657         struct nf_conn *ct;
1658         struct nf_conn_help *help;
1659         int err = 0;
1660
1661         /* caller guarantees that those three CTA_EXPECT_* exist */
1662         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1663         if (err < 0)
1664                 return err;
1665         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1666         if (err < 0)
1667                 return err;
1668         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1669         if (err < 0)
1670                 return err;
1671
1672         /* Look for master conntrack of this expectation */
1673         h = nf_conntrack_find_get(&master_tuple);
1674         if (!h)
1675                 return -ENOENT;
1676         ct = nf_ct_tuplehash_to_ctrack(h);
1677         help = nfct_help(ct);
1678
1679         if (!help || !help->helper) {
1680                 /* such conntrack hasn't got any helper, abort */
1681                 err = -EINVAL;
1682                 goto out;
1683         }
1684
1685         exp = nf_ct_expect_alloc(ct);
1686         if (!exp) {
1687                 err = -ENOMEM;
1688                 goto out;
1689         }
1690
1691         exp->expectfn = NULL;
1692         exp->flags = 0;
1693         exp->master = ct;
1694         exp->helper = NULL;
1695         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1696         memcpy(&exp->mask.src.u3, &mask.src.u3, sizeof(exp->mask.src.u3));
1697         exp->mask.src.u.all = mask.src.u.all;
1698
1699         err = nf_ct_expect_related(exp);
1700         nf_ct_expect_put(exp);
1701
1702 out:
1703         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1704         return err;
1705 }
1706
1707 static int
1708 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1709                      struct nlmsghdr *nlh, struct nlattr *cda[])
1710 {
1711         struct nf_conntrack_tuple tuple;
1712         struct nf_conntrack_expect *exp;
1713         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1714         u_int8_t u3 = nfmsg->nfgen_family;
1715         int err = 0;
1716
1717         if (!cda[CTA_EXPECT_TUPLE]
1718             || !cda[CTA_EXPECT_MASK]
1719             || !cda[CTA_EXPECT_MASTER])
1720                 return -EINVAL;
1721
1722         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1723         if (err < 0)
1724                 return err;
1725
1726         spin_lock_bh(&nf_conntrack_lock);
1727         exp = __nf_ct_expect_find(&tuple);
1728
1729         if (!exp) {
1730                 spin_unlock_bh(&nf_conntrack_lock);
1731                 err = -ENOENT;
1732                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1733                         err = ctnetlink_create_expect(cda, u3);
1734                 return err;
1735         }
1736
1737         err = -EEXIST;
1738         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1739                 err = ctnetlink_change_expect(exp, cda);
1740         spin_unlock_bh(&nf_conntrack_lock);
1741
1742         return err;
1743 }
1744
1745 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1746 static struct notifier_block ctnl_notifier = {
1747         .notifier_call  = ctnetlink_conntrack_event,
1748 };
1749
1750 static struct notifier_block ctnl_notifier_exp = {
1751         .notifier_call  = ctnetlink_expect_event,
1752 };
1753 #endif
1754
1755 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1756         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1757                                             .attr_count = CTA_MAX,
1758                                             .policy = ct_nla_policy },
1759         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1760                                             .attr_count = CTA_MAX,
1761                                             .policy = ct_nla_policy },
1762         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1763                                             .attr_count = CTA_MAX,
1764                                             .policy = ct_nla_policy },
1765         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1766                                             .attr_count = CTA_MAX,
1767                                             .policy = ct_nla_policy },
1768 };
1769
1770 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1771         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1772                                             .attr_count = CTA_EXPECT_MAX,
1773                                             .policy = exp_nla_policy },
1774         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1775                                             .attr_count = CTA_EXPECT_MAX,
1776                                             .policy = exp_nla_policy },
1777         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1778                                             .attr_count = CTA_EXPECT_MAX,
1779                                             .policy = exp_nla_policy },
1780 };
1781
1782 static const struct nfnetlink_subsystem ctnl_subsys = {
1783         .name                           = "conntrack",
1784         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1785         .cb_count                       = IPCTNL_MSG_MAX,
1786         .cb                             = ctnl_cb,
1787 };
1788
1789 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
1790         .name                           = "conntrack_expect",
1791         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1792         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1793         .cb                             = ctnl_exp_cb,
1794 };
1795
1796 MODULE_ALIAS("ip_conntrack_netlink");
1797 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1798 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1799
1800 static int __init ctnetlink_init(void)
1801 {
1802         int ret;
1803
1804         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1805         ret = nfnetlink_subsys_register(&ctnl_subsys);
1806         if (ret < 0) {
1807                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1808                 goto err_out;
1809         }
1810
1811         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1812         if (ret < 0) {
1813                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1814                 goto err_unreg_subsys;
1815         }
1816
1817 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1818         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1819         if (ret < 0) {
1820                 printk("ctnetlink_init: cannot register notifier.\n");
1821                 goto err_unreg_exp_subsys;
1822         }
1823
1824         ret = nf_ct_expect_register_notifier(&ctnl_notifier_exp);
1825         if (ret < 0) {
1826                 printk("ctnetlink_init: cannot expect register notifier.\n");
1827                 goto err_unreg_notifier;
1828         }
1829 #endif
1830
1831         return 0;
1832
1833 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1834 err_unreg_notifier:
1835         nf_conntrack_unregister_notifier(&ctnl_notifier);
1836 err_unreg_exp_subsys:
1837         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1838 #endif
1839 err_unreg_subsys:
1840         nfnetlink_subsys_unregister(&ctnl_subsys);
1841 err_out:
1842         return ret;
1843 }
1844
1845 static void __exit ctnetlink_exit(void)
1846 {
1847         printk("ctnetlink: unregistering from nfnetlink.\n");
1848
1849 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1850         nf_ct_expect_unregister_notifier(&ctnl_notifier_exp);
1851         nf_conntrack_unregister_notifier(&ctnl_notifier);
1852 #endif
1853
1854         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1855         nfnetlink_subsys_unregister(&ctnl_subsys);
1856         return;
1857 }
1858
1859 module_init(ctnetlink_init);
1860 module_exit(ctnetlink_exit);