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   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) 2005-2007 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/types.h>
  22 #include <linux/timer.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/errno.h>
  25 #include <linux/netlink.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/notifier.h>
  29
  30 #include <linux/netfilter.h>
  31 #include <net/netlink.h>
  32 #include <net/netfilter/nf_conntrack.h>
  33 #include <net/netfilter/nf_conntrack_core.h>
  34 #include <net/netfilter/nf_conntrack_expect.h>
  35 #include <net/netfilter/nf_conntrack_helper.h>
  36 #include <net/netfilter/nf_conntrack_l3proto.h>
  37 #include <net/netfilter/nf_conntrack_l4proto.h>
  38 #include <net/netfilter/nf_conntrack_tuple.h>
  39 #ifdef CONFIG_NF_NAT_NEEDED
  40 #include <net/netfilter/nf_nat_core.h>
  41 #include <net/netfilter/nf_nat_protocol.h>
  42 #endif
  43
  44 #include <linux/netfilter/nfnetlink.h>
  45 #include <linux/netfilter/nfnetlink_conntrack.h>
  46
  47 MODULE_LICENSE("GPL");
  48
  49 static char __initdata version[] = "0.93";
  50
  51 static inline int
  52 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  53                             const struct nf_conntrack_tuple *tuple,
  54                             struct nf_conntrack_l4proto *l4proto)
  55 {
  56         int ret = 0;
  57         struct nlattr *nest_parms;
  58
  59         nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO | NLA_F_NESTED);
  60         if (!nest_parms)
  61                 goto nla_put_failure;
  62         NLA_PUT_U8(skb, CTA_PROTO_NUM, tuple->dst.protonum);
  63
  64         if (likely(l4proto->tuple_to_nlattr))
  65                 ret = l4proto->tuple_to_nlattr(skb, tuple);
  66
  67         nla_nest_end(skb, nest_parms);
  68
  69         return ret;
  70
  71 nla_put_failure:
  72         return -1;
  73 }
  74
  75 static inline int
  76 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  77                          const struct nf_conntrack_tuple *tuple,
  78                          struct nf_conntrack_l3proto *l3proto)
  79 {
  80         int ret = 0;
  81         struct nlattr *nest_parms;
  82
  83         nest_parms = nla_nest_start(skb, CTA_TUPLE_IP | NLA_F_NESTED);
  84         if (!nest_parms)
  85                 goto nla_put_failure;
  86
  87         if (likely(l3proto->tuple_to_nlattr))
  88                 ret = l3proto->tuple_to_nlattr(skb, tuple);
  89
  90         nla_nest_end(skb, nest_parms);
  91
  92         return ret;
  93
  94 nla_put_failure:
  95         return -1;
  96 }
  97
  98 static inline int
  99 ctnetlink_dump_tuples(struct sk_buff *skb,
 100                       const struct nf_conntrack_tuple *tuple)
 101 {
 102         int ret;
 103         struct nf_conntrack_l3proto *l3proto;
 104         struct nf_conntrack_l4proto *l4proto;
 105
 106         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 107         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 108         nf_ct_l3proto_put(l3proto);
 109
 110         if (unlikely(ret < 0))
 111                 return ret;
 112
 113         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 114         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
 115         nf_ct_l4proto_put(l4proto);
 116
 117         return ret;
 118 }
 119
 120 static inline int
 121 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 122 {
 123         NLA_PUT_BE32(skb, CTA_STATUS, htonl(ct->status));
 124         return 0;
 125
 126 nla_put_failure:
 127         return -1;
 128 }
 129
 130 static inline int
 131 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 132 {
 133         long timeout = (ct->timeout.expires - jiffies) / HZ;
 134
 135         if (timeout < 0)
 136                 timeout = 0;
 137
 138         NLA_PUT_BE32(skb, CTA_TIMEOUT, htonl(timeout));
 139         return 0;
 140
 141 nla_put_failure:
 142         return -1;
 143 }
 144
 145 static inline int
 146 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 147 {
 148         struct nf_conntrack_l4proto *l4proto = nf_ct_l4proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 149         struct nlattr *nest_proto;
 150         int ret;
 151
 152         if (!l4proto->to_nlattr) {
 153                 nf_ct_l4proto_put(l4proto);
 154                 return 0;
 155         }
 156
 157         nest_proto = nla_nest_start(skb, CTA_PROTOINFO | NLA_F_NESTED);
 158         if (!nest_proto)
 159                 goto nla_put_failure;
 160
 161         ret = l4proto->to_nlattr(skb, nest_proto, ct);
 162
 163         nf_ct_l4proto_put(l4proto);
 164
 165         nla_nest_end(skb, nest_proto);
 166
 167         return ret;
 168
 169 nla_put_failure:
 170         nf_ct_l4proto_put(l4proto);
 171         return -1;
 172 }
 173
 174 static inline int
 175 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 176 {
 177         struct nlattr *nest_helper;
 178         const struct nf_conn_help *help = nfct_help(ct);
 179         struct nf_conntrack_helper *helper;
 180
 181         if (!help)
 182                 return 0;
 183
 184         rcu_read_lock();
 185         helper = rcu_dereference(help->helper);
 186         if (!helper)
 187                 goto out;
 188
 189         nest_helper = nla_nest_start(skb, CTA_HELP | NLA_F_NESTED);
 190         if (!nest_helper)
 191                 goto nla_put_failure;
 192         NLA_PUT_STRING(skb, CTA_HELP_NAME, helper->name);
 193
 194         if (helper->to_nlattr)
 195                 helper->to_nlattr(skb, ct);
 196
 197         nla_nest_end(skb, nest_helper);
 198 out:
 199         rcu_read_unlock();
 200         return 0;
 201
 202 nla_put_failure:
 203         rcu_read_unlock();
 204         return -1;
 205 }
 206
 207 #ifdef CONFIG_NF_CT_ACCT
 208 static inline int
 209 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 210                         enum ip_conntrack_dir dir)
 211 {
 212         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 213         struct nlattr *nest_count;
 214
 215         nest_count = nla_nest_start(skb, type | NLA_F_NESTED);
 216         if (!nest_count)
 217                 goto nla_put_failure;
 218
 219         NLA_PUT_BE32(skb, CTA_COUNTERS32_PACKETS,
 220                      htonl(ct->counters[dir].packets));
 221         NLA_PUT_BE32(skb, CTA_COUNTERS32_BYTES,
 222                      htonl(ct->counters[dir].bytes));
 223
 224         nla_nest_end(skb, nest_count);
 225
 226         return 0;
 227
 228 nla_put_failure:
 229         return -1;
 230 }
 231 #else
 232 #define ctnetlink_dump_counters(a, b, c) (0)
 233 #endif
 234
 235 #ifdef CONFIG_NF_CONNTRACK_MARK
 236 static inline int
 237 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 238 {
 239         NLA_PUT_BE32(skb, CTA_MARK, htonl(ct->mark));
 240         return 0;
 241
 242 nla_put_failure:
 243         return -1;
 244 }
 245 #else
 246 #define ctnetlink_dump_mark(a, b) (0)
 247 #endif
 248
 249 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 250 static inline int
 251 ctnetlink_dump_secmark(struct sk_buff *skb, const struct nf_conn *ct)
 252 {
 253         NLA_PUT_BE32(skb, CTA_SECMARK, htonl(ct->secmark));
 254         return 0;
 255
 256 nla_put_failure:
 257         return -1;
 258 }
 259 #else
 260 #define ctnetlink_dump_secmark(a, b) (0)
 261 #endif
 262
 263 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
 264
 265 static inline int
 266 ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
 267 {
 268         struct nlattr *nest_parms;
 269
 270         if (!(ct->status & IPS_EXPECTED))
 271                 return 0;
 272
 273         nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER | NLA_F_NESTED);
 274         if (!nest_parms)
 275                 goto nla_put_failure;
 276         if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
 277                 goto nla_put_failure;
 278         nla_nest_end(skb, nest_parms);
 279
 280         return 0;
 281
 282 nla_put_failure:
 283         return -1;
 284 }
 285
 286 #ifdef CONFIG_NF_NAT_NEEDED
 287 static inline int
 288 dump_nat_seq_adj(struct sk_buff *skb, const struct nf_nat_seq *natseq, int type)
 289 {
 290         struct nlattr *nest_parms;
 291
 292         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
 293         if (!nest_parms)
 294                 goto nla_put_failure;
 295
 296         NLA_PUT_BE32(skb, CTA_NAT_SEQ_CORRECTION_POS,
 297                      htonl(natseq->correction_pos));
 298         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_BEFORE,
 299                      htonl(natseq->offset_before));
 300         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_AFTER,
 301                      htonl(natseq->offset_after));
 302
 303         nla_nest_end(skb, nest_parms);
 304
 305         return 0;
 306
 307 nla_put_failure:
 308         return -1;
 309 }
 310
 311 static inline int
 312 ctnetlink_dump_nat_seq_adj(struct sk_buff *skb, const struct nf_conn *ct)
 313 {
 314         struct nf_nat_seq *natseq;
 315         struct nf_conn_nat *nat = nfct_nat(ct);
 316
 317         if (!(ct->status & IPS_SEQ_ADJUST) || !nat)
 318                 return 0;
 319
 320         natseq = &nat->seq[IP_CT_DIR_ORIGINAL];
 321         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_ORIG) == -1)
 322                 return -1;
 323
 324         natseq = &nat->seq[IP_CT_DIR_REPLY];
 325         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_REPLY) == -1)
 326                 return -1;
 327
 328         return 0;
 329 }
 330 #else
 331 #define ctnetlink_dump_nat_seq_adj(a, b) (0)
 332 #endif
 333
 334 static inline int
 335 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 336 {
 337         NLA_PUT_BE32(skb, CTA_ID, htonl((unsigned long)ct));
 338         return 0;
 339
 340 nla_put_failure:
 341         return -1;
 342 }
 343
 344 static inline int
 345 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 346 {
 347         NLA_PUT_BE32(skb, CTA_USE, htonl(atomic_read(&ct->ct_general.use)));
 348         return 0;
 349
 350 nla_put_failure:
 351         return -1;
 352 }
 353
 354 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 355
 356 static int
 357 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 358                     int event, int nowait,
 359                     const struct nf_conn *ct)
 360 {
 361         struct nlmsghdr *nlh;
 362         struct nfgenmsg *nfmsg;
 363         struct nlattr *nest_parms;
 364         unsigned char *b = skb_tail_pointer(skb);
 365
 366         event |= NFNL_SUBSYS_CTNETLINK << 8;
 367         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 368         nfmsg  = NLMSG_DATA(nlh);
 369
 370         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 371         nfmsg->nfgen_family =
 372                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 373         nfmsg->version      = NFNETLINK_V0;
 374         nfmsg->res_id       = 0;
 375
 376         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
 377         if (!nest_parms)
 378                 goto nla_put_failure;
 379         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 380                 goto nla_put_failure;
 381         nla_nest_end(skb, nest_parms);
 382
 383         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
 384         if (!nest_parms)
 385                 goto nla_put_failure;
 386         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 387                 goto nla_put_failure;
 388         nla_nest_end(skb, nest_parms);
 389
 390         if (ctnetlink_dump_status(skb, ct) < 0 ||
 391             ctnetlink_dump_timeout(skb, ct) < 0 ||
 392             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 393             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 394             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 395             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 396             ctnetlink_dump_mark(skb, ct) < 0 ||
 397             ctnetlink_dump_secmark(skb, ct) < 0 ||
 398             ctnetlink_dump_id(skb, ct) < 0 ||
 399             ctnetlink_dump_use(skb, ct) < 0 ||
 400             ctnetlink_dump_master(skb, ct) < 0 ||
 401             ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
 402                 goto nla_put_failure;
 403
 404         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 405         return skb->len;
 406
 407 nlmsg_failure:
 408 nla_put_failure:
 409         nlmsg_trim(skb, b);
 410         return -1;
 411 }
 412
 413 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 414 static int ctnetlink_conntrack_event(struct notifier_block *this,
 415                                      unsigned long events, void *ptr)
 416 {
 417         struct nlmsghdr *nlh;
 418         struct nfgenmsg *nfmsg;
 419         struct nlattr *nest_parms;
 420         struct nf_conn *ct = (struct nf_conn *)ptr;
 421         struct sk_buff *skb;
 422         unsigned int type;
 423         sk_buff_data_t b;
 424         unsigned int flags = 0, group;
 425
 426         /* ignore our fake conntrack entry */
 427         if (ct == &nf_conntrack_untracked)
 428                 return NOTIFY_DONE;
 429
 430         if (events & IPCT_DESTROY) {
 431                 type = IPCTNL_MSG_CT_DELETE;
 432                 group = NFNLGRP_CONNTRACK_DESTROY;
 433         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 434                 type = IPCTNL_MSG_CT_NEW;
 435                 flags = NLM_F_CREATE|NLM_F_EXCL;
 436                 group = NFNLGRP_CONNTRACK_NEW;
 437         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 438                 type = IPCTNL_MSG_CT_NEW;
 439                 group = NFNLGRP_CONNTRACK_UPDATE;
 440         } else
 441                 return NOTIFY_DONE;
 442
 443         if (!nfnetlink_has_listeners(group))
 444                 return NOTIFY_DONE;
 445
 446         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 447         if (!skb)
 448                 return NOTIFY_DONE;
 449
 450         b = skb->tail;
 451
 452         type |= NFNL_SUBSYS_CTNETLINK << 8;
 453         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 454         nfmsg = NLMSG_DATA(nlh);
 455
 456         nlh->nlmsg_flags    = flags;
 457         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 458         nfmsg->version  = NFNETLINK_V0;
 459         nfmsg->res_id   = 0;
 460
 461         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
 462         if (!nest_parms)
 463                 goto nla_put_failure;
 464         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 465                 goto nla_put_failure;
 466         nla_nest_end(skb, nest_parms);
 467
 468         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
 469         if (!nest_parms)
 470                 goto nla_put_failure;
 471         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 472                 goto nla_put_failure;
 473         nla_nest_end(skb, nest_parms);
 474
 475         if (events & IPCT_DESTROY) {
 476                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 477                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 478                         goto nla_put_failure;
 479         } else {
 480                 if (ctnetlink_dump_status(skb, ct) < 0)
 481                         goto nla_put_failure;
 482
 483                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 484                         goto nla_put_failure;
 485
 486                 if (events & IPCT_PROTOINFO
 487                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 488                         goto nla_put_failure;
 489
 490                 if ((events & IPCT_HELPER || nfct_help(ct))
 491                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 492                         goto nla_put_failure;
 493
 494 #ifdef CONFIG_NF_CONNTRACK_MARK
 495                 if ((events & IPCT_MARK || ct->mark)
 496                     && ctnetlink_dump_mark(skb, ct) < 0)
 497                         goto nla_put_failure;
 498 #endif
 499 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 500                 if ((events & IPCT_SECMARK || ct->secmark)
 501                     && ctnetlink_dump_secmark(skb, ct) < 0)
 502                         goto nla_put_failure;
 503 #endif
 504
 505                 if (events & IPCT_COUNTER_FILLING &&
 506                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 507                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
 508                         goto nla_put_failure;
 509
 510                 if (events & IPCT_RELATED &&
 511                     ctnetlink_dump_master(skb, ct) < 0)
 512                         goto nla_put_failure;
 513
 514                 if (events & IPCT_NATSEQADJ &&
 515                     ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
 516                         goto nla_put_failure;
 517         }
 518
 519         nlh->nlmsg_len = skb->tail - b;
 520         nfnetlink_send(skb, 0, group, 0);
 521         return NOTIFY_DONE;
 522
 523 nlmsg_failure:
 524 nla_put_failure:
 525         kfree_skb(skb);
 526         return NOTIFY_DONE;
 527 }
 528 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 529
 530 static int ctnetlink_done(struct netlink_callback *cb)
 531 {
 532         if (cb->args[1])
 533                 nf_ct_put((struct nf_conn *)cb->args[1]);
 534         return 0;
 535 }
 536
 537 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 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         read_lock_bh(&nf_conntrack_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(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 && L3PROTO(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                                 nf_conntrack_get(&ct->ct_general);
 572                                 cb->args[1] = (unsigned long)ct;
 573                                 goto out;
 574                         }
 575 #ifdef CONFIG_NF_CT_ACCT
 576                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 577                                                 IPCTNL_MSG_CT_GET_CTRZERO)
 578                                 memset(&ct->counters, 0, sizeof(ct->counters));
 579 #endif
 580                 }
 581                 if (cb->args[1]) {
 582                         cb->args[1] = 0;
 583                         goto restart;
 584                 }
 585         }
 586 out:
 587         read_unlock_bh(&nf_conntrack_lock);
 588         if (last)
 589                 nf_ct_put(last);
 590
 591         return skb->len;
 592 }
 593
 594 static inline int
 595 ctnetlink_parse_tuple_ip(struct nlattr *attr, struct nf_conntrack_tuple *tuple)
 596 {
 597         struct nlattr *tb[CTA_IP_MAX+1];
 598         struct nf_conntrack_l3proto *l3proto;
 599         int ret = 0;
 600
 601         nla_parse_nested(tb, CTA_IP_MAX, attr, NULL);
 602
 603         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 604
 605         if (likely(l3proto->nlattr_to_tuple)) {
 606                 ret = nla_validate_nested(attr, CTA_IP_MAX,
 607                                           l3proto->nla_policy);
 608                 if (ret == 0)
 609                         ret = l3proto->nlattr_to_tuple(tb, tuple);
 610         }
 611
 612         nf_ct_l3proto_put(l3proto);
 613
 614         return ret;
 615 }
 616
 617 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
 618         [CTA_PROTO_NUM] = { .type = NLA_U8 },
 619 };
 620
 621 static inline int
 622 ctnetlink_parse_tuple_proto(struct nlattr *attr,
 623                             struct nf_conntrack_tuple *tuple)
 624 {
 625         struct nlattr *tb[CTA_PROTO_MAX+1];
 626         struct nf_conntrack_l4proto *l4proto;
 627         int ret = 0;
 628
 629         ret = nla_parse_nested(tb, CTA_PROTO_MAX, attr, proto_nla_policy);
 630         if (ret < 0)
 631                 return ret;
 632
 633         if (!tb[CTA_PROTO_NUM])
 634                 return -EINVAL;
 635         tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
 636
 637         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 638
 639         if (likely(l4proto->nlattr_to_tuple)) {
 640                 ret = nla_validate_nested(attr, CTA_PROTO_MAX,
 641                                           l4proto->nla_policy);
 642                 if (ret == 0)
 643                         ret = l4proto->nlattr_to_tuple(tb, tuple);
 644         }
 645
 646         nf_ct_l4proto_put(l4proto);
 647
 648         return ret;
 649 }
 650
 651 static inline int
 652 ctnetlink_parse_tuple(struct nlattr *cda[], struct nf_conntrack_tuple *tuple,
 653                       enum ctattr_tuple type, u_int8_t l3num)
 654 {
 655         struct nlattr *tb[CTA_TUPLE_MAX+1];
 656         int err;
 657
 658         memset(tuple, 0, sizeof(*tuple));
 659
 660         nla_parse_nested(tb, CTA_TUPLE_MAX, cda[type], NULL);
 661
 662         if (!tb[CTA_TUPLE_IP])
 663                 return -EINVAL;
 664
 665         tuple->src.l3num = l3num;
 666
 667         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple);
 668         if (err < 0)
 669                 return err;
 670
 671         if (!tb[CTA_TUPLE_PROTO])
 672                 return -EINVAL;
 673
 674         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple);
 675         if (err < 0)
 676                 return err;
 677
 678         /* orig and expect tuples get DIR_ORIGINAL */
 679         if (type == CTA_TUPLE_REPLY)
 680                 tuple->dst.dir = IP_CT_DIR_REPLY;
 681         else
 682                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 683
 684         return 0;
 685 }
 686
 687 #ifdef CONFIG_NF_NAT_NEEDED
 688 static const struct nla_policy protonat_nla_policy[CTA_PROTONAT_MAX+1] = {
 689         [CTA_PROTONAT_PORT_MIN] = { .type = NLA_U16 },
 690         [CTA_PROTONAT_PORT_MAX] = { .type = NLA_U16 },
 691 };
 692
 693 static int nfnetlink_parse_nat_proto(struct nlattr *attr,
 694                                      const struct nf_conn *ct,
 695                                      struct nf_nat_range *range)
 696 {
 697         struct nlattr *tb[CTA_PROTONAT_MAX+1];
 698         struct nf_nat_protocol *npt;
 699         int err;
 700
 701         err = nla_parse_nested(tb, CTA_PROTONAT_MAX, attr, protonat_nla_policy);
 702         if (err < 0)
 703                 return err;
 704
 705         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 706
 707         if (!npt->nlattr_to_range) {
 708                 nf_nat_proto_put(npt);
 709                 return 0;
 710         }
 711
 712         /* nlattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 713         if (npt->nlattr_to_range(tb, range) > 0)
 714                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 715
 716         nf_nat_proto_put(npt);
 717
 718         return 0;
 719 }
 720
 721 static const struct nla_policy nat_nla_policy[CTA_NAT_MAX+1] = {
 722         [CTA_NAT_MINIP]         = { .type = NLA_U32 },
 723         [CTA_NAT_MAXIP]         = { .type = NLA_U32 },
 724 };
 725
 726 static inline int
 727 nfnetlink_parse_nat(struct nlattr *nat,
 728                     const struct nf_conn *ct, struct nf_nat_range *range)
 729 {
 730         struct nlattr *tb[CTA_NAT_MAX+1];
 731         int err;
 732
 733         memset(range, 0, sizeof(*range));
 734
 735         err = nla_parse_nested(tb, CTA_NAT_MAX, nat, nat_nla_policy);
 736         if (err < 0)
 737                 return err;
 738
 739         if (tb[CTA_NAT_MINIP])
 740                 range->min_ip = nla_get_be32(tb[CTA_NAT_MINIP]);
 741
 742         if (!tb[CTA_NAT_MAXIP])
 743                 range->max_ip = range->min_ip;
 744         else
 745                 range->max_ip = nla_get_be32(tb[CTA_NAT_MAXIP]);
 746
 747         if (range->min_ip)
 748                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 749
 750         if (!tb[CTA_NAT_PROTO])
 751                 return 0;
 752
 753         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO], ct, range);
 754         if (err < 0)
 755                 return err;
 756
 757         return 0;
 758 }
 759 #endif
 760
 761 static inline int
 762 ctnetlink_parse_help(struct nlattr *attr, char **helper_name)
 763 {
 764         struct nlattr *tb[CTA_HELP_MAX+1];
 765
 766         nla_parse_nested(tb, CTA_HELP_MAX, attr, NULL);
 767
 768         if (!tb[CTA_HELP_NAME])
 769                 return -EINVAL;
 770
 771         *helper_name = nla_data(tb[CTA_HELP_NAME]);
 772
 773         return 0;
 774 }
 775
 776 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
 777         [CTA_STATUS]            = { .type = NLA_U32 },
 778         [CTA_TIMEOUT]           = { .type = NLA_U32 },
 779         [CTA_MARK]              = { .type = NLA_U32 },
 780         [CTA_USE]               = { .type = NLA_U32 },
 781         [CTA_ID]                = { .type = NLA_U32 },
 782 };
 783
 784 static int
 785 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 786                         struct nlmsghdr *nlh, struct nlattr *cda[])
 787 {
 788         struct nf_conntrack_tuple_hash *h;
 789         struct nf_conntrack_tuple tuple;
 790         struct nf_conn *ct;
 791         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 792         u_int8_t u3 = nfmsg->nfgen_family;
 793         int err = 0;
 794
 795         if (cda[CTA_TUPLE_ORIG])
 796                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 797         else if (cda[CTA_TUPLE_REPLY])
 798                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 799         else {
 800                 /* Flush the whole table */
 801                 nf_conntrack_flush();
 802                 return 0;
 803         }
 804
 805         if (err < 0)
 806                 return err;
 807
 808         h = nf_conntrack_find_get(&tuple);
 809         if (!h)
 810                 return -ENOENT;
 811
 812         ct = nf_ct_tuplehash_to_ctrack(h);
 813
 814         if (cda[CTA_ID]) {
 815                 u_int32_t id = ntohl(nla_get_be32(cda[CTA_ID]));
 816                 if (id != (u32)(unsigned long)ct) {
 817                         nf_ct_put(ct);
 818                         return -ENOENT;
 819                 }
 820         }
 821         if (del_timer(&ct->timeout))
 822                 ct->timeout.function((unsigned long)ct);
 823
 824         nf_ct_put(ct);
 825
 826         return 0;
 827 }
 828
 829 static int
 830 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 831                         struct nlmsghdr *nlh, struct nlattr *cda[])
 832 {
 833         struct nf_conntrack_tuple_hash *h;
 834         struct nf_conntrack_tuple tuple;
 835         struct nf_conn *ct;
 836         struct sk_buff *skb2 = NULL;
 837         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 838         u_int8_t u3 = nfmsg->nfgen_family;
 839         int err = 0;
 840
 841         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 842 #ifndef CONFIG_NF_CT_ACCT
 843                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
 844                         return -ENOTSUPP;
 845 #endif
 846                 return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
 847                                           ctnetlink_done);
 848         }
 849
 850         if (cda[CTA_TUPLE_ORIG])
 851                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 852         else if (cda[CTA_TUPLE_REPLY])
 853                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 854         else
 855                 return -EINVAL;
 856
 857         if (err < 0)
 858                 return err;
 859
 860         h = nf_conntrack_find_get(&tuple);
 861         if (!h)
 862                 return -ENOENT;
 863
 864         ct = nf_ct_tuplehash_to_ctrack(h);
 865
 866         err = -ENOMEM;
 867         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 868         if (!skb2) {
 869                 nf_ct_put(ct);
 870                 return -ENOMEM;
 871         }
 872
 873         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 874                                   IPCTNL_MSG_CT_NEW, 1, ct);
 875         nf_ct_put(ct);
 876         if (err <= 0)
 877                 goto free;
 878
 879         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 880         if (err < 0)
 881                 goto out;
 882
 883         return 0;
 884
 885 free:
 886         kfree_skb(skb2);
 887 out:
 888         return err;
 889 }
 890
 891 static inline int
 892 ctnetlink_change_status(struct nf_conn *ct, struct nlattr *cda[])
 893 {
 894         unsigned long d;
 895         unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
 896         d = ct->status ^ status;
 897
 898         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 899                 /* unchangeable */
 900                 return -EINVAL;
 901
 902         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 903                 /* SEEN_REPLY bit can only be set */
 904                 return -EINVAL;
 905
 906
 907         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 908                 /* ASSURED bit can only be set */
 909                 return -EINVAL;
 910
 911         if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
 912 #ifndef CONFIG_NF_NAT_NEEDED
 913                 return -EINVAL;
 914 #else
 915                 struct nf_nat_range range;
 916
 917                 if (cda[CTA_NAT_DST]) {
 918                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST], ct,
 919                                                 &range) < 0)
 920                                 return -EINVAL;
 921                         if (nf_nat_initialized(ct,
 922                                                HOOK2MANIP(NF_INET_PRE_ROUTING)))
 923                                 return -EEXIST;
 924                         nf_nat_setup_info(ct, &range, NF_INET_PRE_ROUTING);
 925                 }
 926                 if (cda[CTA_NAT_SRC]) {
 927                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC], ct,
 928                                                 &range) < 0)
 929                                 return -EINVAL;
 930                         if (nf_nat_initialized(ct,
 931                                                HOOK2MANIP(NF_INET_POST_ROUTING)))
 932                                 return -EEXIST;
 933                         nf_nat_setup_info(ct, &range, NF_INET_POST_ROUTING);
 934                 }
 935 #endif
 936         }
 937
 938         /* Be careful here, modifying NAT bits can screw up things,
 939          * so don't let users modify them directly if they don't pass
 940          * nf_nat_range. */
 941         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 942         return 0;
 943 }
 944
 945
 946 static inline int
 947 ctnetlink_change_helper(struct nf_conn *ct, struct nlattr *cda[])
 948 {
 949         struct nf_conntrack_helper *helper;
 950         struct nf_conn_help *help = nfct_help(ct);
 951         char *helpname;
 952         int err;
 953
 954         /* don't change helper of sibling connections */
 955         if (ct->master)
 956                 return -EINVAL;
 957
 958         err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
 959         if (err < 0)
 960                 return err;
 961
 962         if (!strcmp(helpname, "")) {
 963                 if (help && help->helper) {
 964                         /* we had a helper before ... */
 965                         nf_ct_remove_expectations(ct);
 966                         rcu_assign_pointer(help->helper, NULL);
 967                 }
 968
 969                 return 0;
 970         }
 971
 972         helper = __nf_conntrack_helper_find_byname(helpname);
 973         if (helper == NULL)
 974                 return -EINVAL;
 975
 976         if (help) {
 977                 if (help->helper == helper)
 978                         return 0;
 979                 if (help->helper)
 980                         return -EBUSY;
 981                 /* need to zero data of old helper */
 982                 memset(&help->help, 0, sizeof(help->help));
 983         } else {
 984                 help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
 985                 if (help == NULL)
 986                         return -ENOMEM;
 987         }
 988
 989         rcu_assign_pointer(help->helper, helper);
 990
 991         return 0;
 992 }
 993
 994 static inline int
 995 ctnetlink_change_timeout(struct nf_conn *ct, struct nlattr *cda[])
 996 {
 997         u_int32_t timeout = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
 998
 999         if (!del_timer(&ct->timeout))
1000                 return -ETIME;
1001
1002         ct->timeout.expires = jiffies + timeout * HZ;
1003         add_timer(&ct->timeout);
1004
1005         return 0;
1006 }
1007
1008 static inline int
1009 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nlattr *cda[])
1010 {
1011         struct nlattr *tb[CTA_PROTOINFO_MAX+1], *attr = cda[CTA_PROTOINFO];
1012         struct nf_conntrack_l4proto *l4proto;
1013         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
1014         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
1015         int err = 0;
1016
1017         nla_parse_nested(tb, CTA_PROTOINFO_MAX, attr, NULL);
1018
1019         l4proto = nf_ct_l4proto_find_get(l3num, npt);
1020
1021         if (l4proto->from_nlattr)
1022                 err = l4proto->from_nlattr(tb, ct);
1023         nf_ct_l4proto_put(l4proto);
1024
1025         return err;
1026 }
1027
1028 #ifdef CONFIG_NF_NAT_NEEDED
1029 static inline int
1030 change_nat_seq_adj(struct nf_nat_seq *natseq, struct nlattr *attr)
1031 {
1032         struct nlattr *cda[CTA_NAT_SEQ_MAX+1];
1033
1034         nla_parse_nested(cda, CTA_NAT_SEQ_MAX, attr, NULL);
1035
1036         if (!cda[CTA_NAT_SEQ_CORRECTION_POS])
1037                 return -EINVAL;
1038
1039         natseq->correction_pos =
1040                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_CORRECTION_POS]));
1041
1042         if (!cda[CTA_NAT_SEQ_OFFSET_BEFORE])
1043                 return -EINVAL;
1044
1045         natseq->offset_before =
1046                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_BEFORE]));
1047
1048         if (!cda[CTA_NAT_SEQ_OFFSET_AFTER])
1049                 return -EINVAL;
1050
1051         natseq->offset_after =
1052                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_AFTER]));
1053
1054         return 0;
1055 }
1056
1057 static int
1058 ctnetlink_change_nat_seq_adj(struct nf_conn *ct, struct nlattr *cda[])
1059 {
1060         int ret = 0;
1061         struct nf_conn_nat *nat = nfct_nat(ct);
1062
1063         if (!nat)
1064                 return 0;
1065
1066         if (cda[CTA_NAT_SEQ_ADJ_ORIG]) {
1067                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_ORIGINAL],
1068                                          cda[CTA_NAT_SEQ_ADJ_ORIG]);
1069                 if (ret < 0)
1070                         return ret;
1071
1072                 ct->status |= IPS_SEQ_ADJUST;
1073         }
1074
1075         if (cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1076                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_REPLY],
1077                                          cda[CTA_NAT_SEQ_ADJ_REPLY]);
1078                 if (ret < 0)
1079                         return ret;
1080
1081                 ct->status |= IPS_SEQ_ADJUST;
1082         }
1083
1084         return 0;
1085 }
1086 #endif
1087
1088 static int
1089 ctnetlink_change_conntrack(struct nf_conn *ct, struct nlattr *cda[])
1090 {
1091         int err;
1092
1093         if (cda[CTA_HELP]) {
1094                 err = ctnetlink_change_helper(ct, cda);
1095                 if (err < 0)
1096                         return err;
1097         }
1098
1099         if (cda[CTA_TIMEOUT]) {
1100                 err = ctnetlink_change_timeout(ct, cda);
1101                 if (err < 0)
1102                         return err;
1103         }
1104
1105         if (cda[CTA_STATUS]) {
1106                 err = ctnetlink_change_status(ct, cda);
1107                 if (err < 0)
1108                         return err;
1109         }
1110
1111         if (cda[CTA_PROTOINFO]) {
1112                 err = ctnetlink_change_protoinfo(ct, cda);
1113                 if (err < 0)
1114                         return err;
1115         }
1116
1117 #if defined(CONFIG_NF_CONNTRACK_MARK)
1118         if (cda[CTA_MARK])
1119                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1120 #endif
1121
1122 #ifdef CONFIG_NF_NAT_NEEDED
1123         if (cda[CTA_NAT_SEQ_ADJ_ORIG] || cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1124                 err = ctnetlink_change_nat_seq_adj(ct, cda);
1125                 if (err < 0)
1126                         return err;
1127         }
1128 #endif
1129
1130         return 0;
1131 }
1132
1133 static int
1134 ctnetlink_create_conntrack(struct nlattr *cda[],
1135                            struct nf_conntrack_tuple *otuple,
1136                            struct nf_conntrack_tuple *rtuple,
1137                            struct nf_conn *master_ct)
1138 {
1139         struct nf_conn *ct;
1140         int err = -EINVAL;
1141         struct nf_conn_help *help;
1142         struct nf_conntrack_helper *helper;
1143
1144         ct = nf_conntrack_alloc(otuple, rtuple);
1145         if (ct == NULL || IS_ERR(ct))
1146                 return -ENOMEM;
1147
1148         if (!cda[CTA_TIMEOUT])
1149                 goto err;
1150         ct->timeout.expires = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
1151
1152         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1153         ct->status |= IPS_CONFIRMED;
1154
1155         if (cda[CTA_STATUS]) {
1156                 err = ctnetlink_change_status(ct, cda);
1157                 if (err < 0)
1158                         goto err;
1159         }
1160
1161         if (cda[CTA_PROTOINFO]) {
1162                 err = ctnetlink_change_protoinfo(ct, cda);
1163                 if (err < 0)
1164                         goto err;
1165         }
1166
1167 #if defined(CONFIG_NF_CONNTRACK_MARK)
1168         if (cda[CTA_MARK])
1169                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1170 #endif
1171
1172         helper = nf_ct_helper_find_get(rtuple);
1173         if (helper) {
1174                 help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
1175                 if (help == NULL) {
1176                         nf_ct_helper_put(helper);
1177                         err = -ENOMEM;
1178                         goto err;
1179                 }
1180                 /* not in hash table yet so not strictly necessary */
1181                 rcu_assign_pointer(help->helper, helper);
1182         }
1183
1184         /* setup master conntrack: this is a confirmed expectation */
1185         if (master_ct) {
1186                 __set_bit(IPS_EXPECTED_BIT, &ct->status);
1187                 ct->master = master_ct;
1188         }
1189
1190         add_timer(&ct->timeout);
1191         nf_conntrack_hash_insert(ct);
1192
1193         if (helper)
1194                 nf_ct_helper_put(helper);
1195
1196         return 0;
1197
1198 err:
1199         nf_conntrack_free(ct);
1200         return err;
1201 }
1202
1203 static int
1204 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1205                         struct nlmsghdr *nlh, struct nlattr *cda[])
1206 {
1207         struct nf_conntrack_tuple otuple, rtuple;
1208         struct nf_conntrack_tuple_hash *h = NULL;
1209         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1210         u_int8_t u3 = nfmsg->nfgen_family;
1211         int err = 0;
1212
1213         if (cda[CTA_TUPLE_ORIG]) {
1214                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1215                 if (err < 0)
1216                         return err;
1217         }
1218
1219         if (cda[CTA_TUPLE_REPLY]) {
1220                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1221                 if (err < 0)
1222                         return err;
1223         }
1224
1225         write_lock_bh(&nf_conntrack_lock);
1226         if (cda[CTA_TUPLE_ORIG])
1227                 h = __nf_conntrack_find(&otuple, NULL);
1228         else if (cda[CTA_TUPLE_REPLY])
1229                 h = __nf_conntrack_find(&rtuple, NULL);
1230
1231         if (h == NULL) {
1232                 struct nf_conntrack_tuple master;
1233                 struct nf_conntrack_tuple_hash *master_h = NULL;
1234                 struct nf_conn *master_ct = NULL;
1235
1236                 if (cda[CTA_TUPLE_MASTER]) {
1237                         err = ctnetlink_parse_tuple(cda,
1238                                                     &master,
1239                                                     CTA_TUPLE_MASTER,
1240                                                     u3);
1241                         if (err < 0)
1242                                 return err;
1243
1244                         master_h = __nf_conntrack_find(&master, NULL);
1245                         if (master_h == NULL) {
1246                                 err = -ENOENT;
1247                                 goto out_unlock;
1248                         }
1249                         master_ct = nf_ct_tuplehash_to_ctrack(master_h);
1250                         atomic_inc(&master_ct->ct_general.use);
1251                 }
1252
1253                 write_unlock_bh(&nf_conntrack_lock);
1254                 err = -ENOENT;
1255                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1256                         err = ctnetlink_create_conntrack(cda,
1257                                                          &otuple,
1258                                                          &rtuple,
1259                                                          master_ct);
1260                 if (err < 0 && master_ct)
1261                         nf_ct_put(master_ct);
1262
1263                 return err;
1264         }
1265         /* implicit 'else' */
1266
1267         /* We manipulate the conntrack inside the global conntrack table lock,
1268          * so there's no need to increase the refcount */
1269         err = -EEXIST;
1270         if (!(nlh->nlmsg_flags & NLM_F_EXCL)) {
1271                 /* we only allow nat config for new conntracks */
1272                 if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
1273                         err = -EINVAL;
1274                         goto out_unlock;
1275                 }
1276                 /* can't link an existing conntrack to a master */
1277                 if (cda[CTA_TUPLE_MASTER]) {
1278                         err = -EINVAL;
1279                         goto out_unlock;
1280                 }
1281                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h),
1282                                                  cda);
1283         }
1284
1285 out_unlock:
1286         write_unlock_bh(&nf_conntrack_lock);
1287         return err;
1288 }
1289
1290 /***********************************************************************
1291  * EXPECT
1292  ***********************************************************************/
1293
1294 static inline int
1295 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1296                          const struct nf_conntrack_tuple *tuple,
1297                          enum ctattr_expect type)
1298 {
1299         struct nlattr *nest_parms;
1300
1301         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
1302         if (!nest_parms)
1303                 goto nla_put_failure;
1304         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1305                 goto nla_put_failure;
1306         nla_nest_end(skb, nest_parms);
1307
1308         return 0;
1309
1310 nla_put_failure:
1311         return -1;
1312 }
1313
1314 static inline int
1315 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1316                         const struct nf_conntrack_tuple *tuple,
1317                         const struct nf_conntrack_tuple_mask *mask)
1318 {
1319         int ret;
1320         struct nf_conntrack_l3proto *l3proto;
1321         struct nf_conntrack_l4proto *l4proto;
1322         struct nf_conntrack_tuple m;
1323         struct nlattr *nest_parms;
1324
1325         memset(&m, 0xFF, sizeof(m));
1326         m.src.u.all = mask->src.u.all;
1327         memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
1328
1329         nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK | NLA_F_NESTED);
1330         if (!nest_parms)
1331                 goto nla_put_failure;
1332
1333         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1334         ret = ctnetlink_dump_tuples_ip(skb, &m, l3proto);
1335         nf_ct_l3proto_put(l3proto);
1336
1337         if (unlikely(ret < 0))
1338                 goto nla_put_failure;
1339
1340         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1341         ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
1342         nf_ct_l4proto_put(l4proto);
1343         if (unlikely(ret < 0))
1344                 goto nla_put_failure;
1345
1346         nla_nest_end(skb, nest_parms);
1347
1348         return 0;
1349
1350 nla_put_failure:
1351         return -1;
1352 }
1353
1354 static inline int
1355 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1356                           const struct nf_conntrack_expect *exp)
1357 {
1358         struct nf_conn *master = exp->master;
1359         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1360
1361         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1362                 goto nla_put_failure;
1363         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1364                 goto nla_put_failure;
1365         if (ctnetlink_exp_dump_tuple(skb,
1366                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1367                                  CTA_EXPECT_MASTER) < 0)
1368                 goto nla_put_failure;
1369
1370         NLA_PUT_BE32(skb, CTA_EXPECT_TIMEOUT, timeout);
1371         NLA_PUT_BE32(skb, CTA_EXPECT_ID, htonl((unsigned long)exp));
1372
1373         return 0;
1374
1375 nla_put_failure:
1376         return -1;
1377 }
1378
1379 static int
1380 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1381                     int event,
1382                     int nowait,
1383                     const struct nf_conntrack_expect *exp)
1384 {
1385         struct nlmsghdr *nlh;
1386         struct nfgenmsg *nfmsg;
1387         unsigned char *b = skb_tail_pointer(skb);
1388
1389         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1390         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1391         nfmsg  = NLMSG_DATA(nlh);
1392
1393         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1394         nfmsg->nfgen_family = exp->tuple.src.l3num;
1395         nfmsg->version      = NFNETLINK_V0;
1396         nfmsg->res_id       = 0;
1397
1398         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1399                 goto nla_put_failure;
1400
1401         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1402         return skb->len;
1403
1404 nlmsg_failure:
1405 nla_put_failure:
1406         nlmsg_trim(skb, b);
1407         return -1;
1408 }
1409
1410 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1411 static int ctnetlink_expect_event(struct notifier_block *this,
1412                                   unsigned long events, void *ptr)
1413 {
1414         struct nlmsghdr *nlh;
1415         struct nfgenmsg *nfmsg;
1416         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1417         struct sk_buff *skb;
1418         unsigned int type;
1419         sk_buff_data_t b;
1420         int flags = 0;
1421
1422         if (events & IPEXP_NEW) {
1423                 type = IPCTNL_MSG_EXP_NEW;
1424                 flags = NLM_F_CREATE|NLM_F_EXCL;
1425         } else
1426                 return NOTIFY_DONE;
1427
1428         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1429                 return NOTIFY_DONE;
1430
1431         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1432         if (!skb)
1433                 return NOTIFY_DONE;
1434
1435         b = skb->tail;
1436
1437         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1438         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1439         nfmsg = NLMSG_DATA(nlh);
1440
1441         nlh->nlmsg_flags    = flags;
1442         nfmsg->nfgen_family = exp->tuple.src.l3num;
1443         nfmsg->version      = NFNETLINK_V0;
1444         nfmsg->res_id       = 0;
1445
1446         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1447                 goto nla_put_failure;
1448
1449         nlh->nlmsg_len = skb->tail - b;
1450         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1451         return NOTIFY_DONE;
1452
1453 nlmsg_failure:
1454 nla_put_failure:
1455         kfree_skb(skb);
1456         return NOTIFY_DONE;
1457 }
1458 #endif
1459 static int ctnetlink_exp_done(struct netlink_callback *cb)
1460 {
1461         if (cb->args[1])
1462                 nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
1463         return 0;
1464 }
1465
1466 static int
1467 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1468 {
1469         struct nf_conntrack_expect *exp, *last;
1470         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1471         struct hlist_node *n;
1472         u_int8_t l3proto = nfmsg->nfgen_family;
1473
1474         read_lock_bh(&nf_conntrack_lock);
1475         last = (struct nf_conntrack_expect *)cb->args[1];
1476         for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
1477 restart:
1478                 hlist_for_each_entry(exp, n, &nf_ct_expect_hash[cb->args[0]],
1479                                      hnode) {
1480                         if (l3proto && exp->tuple.src.l3num != l3proto)
1481                                 continue;
1482                         if (cb->args[1]) {
1483                                 if (exp != last)
1484                                         continue;
1485                                 cb->args[1] = 0;
1486                         }
1487                         if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1488                                                     cb->nlh->nlmsg_seq,
1489                                                     IPCTNL_MSG_EXP_NEW,
1490                                                     1, exp) < 0) {
1491                                 atomic_inc(&exp->use);
1492                                 cb->args[1] = (unsigned long)exp;
1493                                 goto out;
1494                         }
1495                 }
1496                 if (cb->args[1]) {
1497                         cb->args[1] = 0;
1498                         goto restart;
1499                 }
1500         }
1501 out:
1502         read_unlock_bh(&nf_conntrack_lock);
1503         if (last)
1504                 nf_ct_expect_put(last);
1505
1506         return skb->len;
1507 }
1508
1509 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
1510         [CTA_EXPECT_TIMEOUT]    = { .type = NLA_U32 },
1511         [CTA_EXPECT_ID]         = { .type = NLA_U32 },
1512 };
1513
1514 static int
1515 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1516                      struct nlmsghdr *nlh, struct nlattr *cda[])
1517 {
1518         struct nf_conntrack_tuple tuple;
1519         struct nf_conntrack_expect *exp;
1520         struct sk_buff *skb2;
1521         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1522         u_int8_t u3 = nfmsg->nfgen_family;
1523         int err = 0;
1524
1525         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1526                 return netlink_dump_start(ctnl, skb, nlh,
1527                                           ctnetlink_exp_dump_table,
1528                                           ctnetlink_exp_done);
1529         }
1530
1531         if (cda[CTA_EXPECT_MASTER])
1532                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1533         else
1534                 return -EINVAL;
1535
1536         if (err < 0)
1537                 return err;
1538
1539         exp = nf_ct_expect_find_get(&tuple);
1540         if (!exp)
1541                 return -ENOENT;
1542
1543         if (cda[CTA_EXPECT_ID]) {
1544                 __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1545                 if (ntohl(id) != (u32)(unsigned long)exp) {
1546                         nf_ct_expect_put(exp);
1547                         return -ENOENT;
1548                 }
1549         }
1550
1551         err = -ENOMEM;
1552         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1553         if (!skb2)
1554                 goto out;
1555
1556         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1557                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1558                                       1, exp);
1559         if (err <= 0)
1560                 goto free;
1561
1562         nf_ct_expect_put(exp);
1563
1564         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1565
1566 free:
1567         kfree_skb(skb2);
1568 out:
1569         nf_ct_expect_put(exp);
1570         return err;
1571 }
1572
1573 static int
1574 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1575                      struct nlmsghdr *nlh, struct nlattr *cda[])
1576 {
1577         struct nf_conntrack_expect *exp;
1578         struct nf_conntrack_tuple tuple;
1579         struct nf_conntrack_helper *h;
1580         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1581         struct hlist_node *n, *next;
1582         u_int8_t u3 = nfmsg->nfgen_family;
1583         unsigned int i;
1584         int err;
1585
1586         if (cda[CTA_EXPECT_TUPLE]) {
1587                 /* delete a single expect by tuple */
1588                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1589                 if (err < 0)
1590                         return err;
1591
1592                 /* bump usage count to 2 */
1593                 exp = nf_ct_expect_find_get(&tuple);
1594                 if (!exp)
1595                         return -ENOENT;
1596
1597                 if (cda[CTA_EXPECT_ID]) {
1598                         __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1599                         if (ntohl(id) != (u32)(unsigned long)exp) {
1600                                 nf_ct_expect_put(exp);
1601                                 return -ENOENT;
1602                         }
1603                 }
1604
1605                 /* after list removal, usage count == 1 */
1606                 nf_ct_unexpect_related(exp);
1607                 /* have to put what we 'get' above.
1608                  * after this line usage count == 0 */
1609                 nf_ct_expect_put(exp);
1610         } else if (cda[CTA_EXPECT_HELP_NAME]) {
1611                 char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
1612                 struct nf_conn_help *m_help;
1613
1614                 /* delete all expectations for this helper */
1615                 write_lock_bh(&nf_conntrack_lock);
1616                 h = __nf_conntrack_helper_find_byname(name);
1617                 if (!h) {
1618                         write_unlock_bh(&nf_conntrack_lock);
1619                         return -EINVAL;
1620                 }
1621                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1622                         hlist_for_each_entry_safe(exp, n, next,
1623                                                   &nf_ct_expect_hash[i],
1624                                                   hnode) {
1625                                 m_help = nfct_help(exp->master);
1626                                 if (m_help->helper == h
1627                                     && del_timer(&exp->timeout)) {
1628                                         nf_ct_unlink_expect(exp);
1629                                         nf_ct_expect_put(exp);
1630                                 }
1631                         }
1632                 }
1633                 write_unlock_bh(&nf_conntrack_lock);
1634         } else {
1635                 /* This basically means we have to flush everything*/
1636                 write_lock_bh(&nf_conntrack_lock);
1637                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1638                         hlist_for_each_entry_safe(exp, n, next,
1639                                                   &nf_ct_expect_hash[i],
1640                                                   hnode) {
1641                                 if (del_timer(&exp->timeout)) {
1642                                         nf_ct_unlink_expect(exp);
1643                                         nf_ct_expect_put(exp);
1644                                 }
1645                         }
1646                 }
1647                 write_unlock_bh(&nf_conntrack_lock);
1648         }
1649
1650         return 0;
1651 }
1652 static int
1653 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nlattr *cda[])
1654 {
1655         return -EOPNOTSUPP;
1656 }
1657
1658 static int
1659 ctnetlink_create_expect(struct nlattr *cda[], u_int8_t u3)
1660 {
1661         struct nf_conntrack_tuple tuple, mask, master_tuple;
1662         struct nf_conntrack_tuple_hash *h = NULL;
1663         struct nf_conntrack_expect *exp;
1664         struct nf_conn *ct;
1665         struct nf_conn_help *help;
1666         int err = 0;
1667
1668         /* caller guarantees that those three CTA_EXPECT_* exist */
1669         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1670         if (err < 0)
1671                 return err;
1672         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1673         if (err < 0)
1674                 return err;
1675         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1676         if (err < 0)
1677                 return err;
1678
1679         /* Look for master conntrack of this expectation */
1680         h = nf_conntrack_find_get(&master_tuple);
1681         if (!h)
1682                 return -ENOENT;
1683         ct = nf_ct_tuplehash_to_ctrack(h);
1684         help = nfct_help(ct);
1685
1686         if (!help || !help->helper) {
1687                 /* such conntrack hasn't got any helper, abort */
1688                 err = -EINVAL;
1689                 goto out;
1690         }
1691
1692         exp = nf_ct_expect_alloc(ct);
1693         if (!exp) {
1694                 err = -ENOMEM;
1695                 goto out;
1696         }
1697
1698         exp->expectfn = NULL;
1699         exp->flags = 0;
1700         exp->master = ct;
1701         exp->helper = NULL;
1702         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1703         memcpy(&exp->mask.src.u3, &mask.src.u3, sizeof(exp->mask.src.u3));
1704         exp->mask.src.u.all = mask.src.u.all;
1705
1706         err = nf_ct_expect_related(exp);
1707         nf_ct_expect_put(exp);
1708
1709 out:
1710         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1711         return err;
1712 }
1713
1714 static int
1715 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1716                      struct nlmsghdr *nlh, struct nlattr *cda[])
1717 {
1718         struct nf_conntrack_tuple tuple;
1719         struct nf_conntrack_expect *exp;
1720         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1721         u_int8_t u3 = nfmsg->nfgen_family;
1722         int err = 0;
1723
1724         if (!cda[CTA_EXPECT_TUPLE]
1725             || !cda[CTA_EXPECT_MASK]
1726             || !cda[CTA_EXPECT_MASTER])
1727                 return -EINVAL;
1728
1729         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1730         if (err < 0)
1731                 return err;
1732
1733         write_lock_bh(&nf_conntrack_lock);
1734         exp = __nf_ct_expect_find(&tuple);
1735
1736         if (!exp) {
1737                 write_unlock_bh(&nf_conntrack_lock);
1738                 err = -ENOENT;
1739                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1740                         err = ctnetlink_create_expect(cda, u3);
1741                 return err;
1742         }
1743
1744         err = -EEXIST;
1745         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1746                 err = ctnetlink_change_expect(exp, cda);
1747         write_unlock_bh(&nf_conntrack_lock);
1748
1749         return err;
1750 }
1751
1752 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1753 static struct notifier_block ctnl_notifier = {
1754         .notifier_call  = ctnetlink_conntrack_event,
1755 };
1756
1757 static struct notifier_block ctnl_notifier_exp = {
1758         .notifier_call  = ctnetlink_expect_event,
1759 };
1760 #endif
1761
1762 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1763         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1764                                             .attr_count = CTA_MAX,
1765                                             .policy = ct_nla_policy },
1766         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1767                                             .attr_count = CTA_MAX,
1768                                             .policy = ct_nla_policy },
1769         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1770                                             .attr_count = CTA_MAX,
1771                                             .policy = ct_nla_policy },
1772         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1773                                             .attr_count = CTA_MAX,
1774                                             .policy = ct_nla_policy },
1775 };
1776
1777 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1778         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1779                                             .attr_count = CTA_EXPECT_MAX,
1780                                             .policy = exp_nla_policy },
1781         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1782                                             .attr_count = CTA_EXPECT_MAX,
1783                                             .policy = exp_nla_policy },
1784         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1785                                             .attr_count = CTA_EXPECT_MAX,
1786                                             .policy = exp_nla_policy },
1787 };
1788
1789 static const struct nfnetlink_subsystem ctnl_subsys = {
1790         .name                           = "conntrack",
1791         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1792         .cb_count                       = IPCTNL_MSG_MAX,
1793         .cb                             = ctnl_cb,
1794 };
1795
1796 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
1797         .name                           = "conntrack_expect",
1798         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1799         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1800         .cb                             = ctnl_exp_cb,
1801 };
1802
1803 MODULE_ALIAS("ip_conntrack_netlink");
1804 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1805 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1806
1807 static int __init ctnetlink_init(void)
1808 {
1809         int ret;
1810
1811         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1812         ret = nfnetlink_subsys_register(&ctnl_subsys);
1813         if (ret < 0) {
1814                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1815                 goto err_out;
1816         }
1817
1818         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1819         if (ret < 0) {
1820                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1821                 goto err_unreg_subsys;
1822         }
1823
1824 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1825         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1826         if (ret < 0) {
1827                 printk("ctnetlink_init: cannot register notifier.\n");
1828                 goto err_unreg_exp_subsys;
1829         }
1830
1831         ret = nf_ct_expect_register_notifier(&ctnl_notifier_exp);
1832         if (ret < 0) {
1833                 printk("ctnetlink_init: cannot expect register notifier.\n");
1834                 goto err_unreg_notifier;
1835         }
1836 #endif
1837
1838         return 0;
1839
1840 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1841 err_unreg_notifier:
1842         nf_conntrack_unregister_notifier(&ctnl_notifier);
1843 err_unreg_exp_subsys:
1844         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1845 #endif
1846 err_unreg_subsys:
1847         nfnetlink_subsys_unregister(&ctnl_subsys);
1848 err_out:
1849         return ret;
1850 }
1851
1852 static void __exit ctnetlink_exit(void)
1853 {
1854         printk("ctnetlink: unregistering from nfnetlink.\n");
1855
1856 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1857         nf_ct_expect_unregister_notifier(&ctnl_notifier_exp);
1858         nf_conntrack_unregister_notifier(&ctnl_notifier);
1859 #endif
1860
1861         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1862         nfnetlink_subsys_unregister(&ctnl_subsys);
1863         return;
1864 }
1865
1866 module_init(ctnetlink_init);
1867 module_exit(ctnetlink_exit);