net/ipv4/netfilter/ip_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) 2002-2005 by Harald Welte <laforge@gnumonks.org>
   6  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
   7  * (C) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net>
   8  *
   9  * I've reworked this stuff to use attributes instead of conntrack
  10  * structures. 5.44 am. I need more tea. --pablo 05/07/11.
  11  *
  12  * Initial connection tracking via netlink development funded and
  13  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
  14  *
  15  * Further development of this code funded by Astaro AG (http://www.astaro.com)
  16  *
  17  * This software may be used and distributed according to the terms
  18  * of the GNU General Public License, incorporated herein by reference.
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/types.h>
  25 #include <linux/timer.h>
  26 #include <linux/skbuff.h>
  27 #include <linux/errno.h>
  28 #include <linux/netlink.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/notifier.h>
  32
  33 #include <linux/netfilter.h>
  34 #include <linux/netfilter_ipv4/ip_conntrack.h>
  35 #include <linux/netfilter_ipv4/ip_conntrack_core.h>
  36 #include <linux/netfilter_ipv4/ip_conntrack_helper.h>
  37 #include <linux/netfilter_ipv4/ip_conntrack_protocol.h>
  38 #include <linux/netfilter_ipv4/ip_nat_protocol.h>
  39
  40 #include <linux/netfilter/nfnetlink.h>
  41 #include <linux/netfilter/nfnetlink_conntrack.h>
  42
  43 MODULE_LICENSE("GPL");
  44
  45 static char __initdata version[] = "0.90";
  46
  47 static inline int
  48 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  49                             const struct ip_conntrack_tuple *tuple,
  50                             struct ip_conntrack_protocol *proto)
  51 {
  52         int ret = 0;
  53         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  54
  55         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  56
  57         if (likely(proto->tuple_to_nfattr))
  58                 ret = proto->tuple_to_nfattr(skb, tuple);
  59
  60         NFA_NEST_END(skb, nest_parms);
  61
  62         return ret;
  63
  64 nfattr_failure:
  65         return -1;
  66 }
  67
  68 static inline int
  69 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  70                          const struct ip_conntrack_tuple *tuple)
  71 {
  72         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  73
  74         NFA_PUT(skb, CTA_IP_V4_SRC, sizeof(__be32), &tuple->src.ip);
  75         NFA_PUT(skb, CTA_IP_V4_DST, sizeof(__be32), &tuple->dst.ip);
  76
  77         NFA_NEST_END(skb, nest_parms);
  78
  79         return 0;
  80
  81 nfattr_failure:
  82         return -1;
  83 }
  84
  85 static inline int
  86 ctnetlink_dump_tuples(struct sk_buff *skb,
  87                       const struct ip_conntrack_tuple *tuple)
  88 {
  89         int ret;
  90         struct ip_conntrack_protocol *proto;
  91
  92         ret = ctnetlink_dump_tuples_ip(skb, tuple);
  93         if (unlikely(ret < 0))
  94                 return ret;
  95
  96         proto = ip_conntrack_proto_find_get(tuple->dst.protonum);
  97         ret = ctnetlink_dump_tuples_proto(skb, tuple, proto);
  98         ip_conntrack_proto_put(proto);
  99
 100         return ret;
 101 }
 102
 103 static inline int
 104 ctnetlink_dump_status(struct sk_buff *skb, const struct ip_conntrack *ct)
 105 {
 106         __be32 status = htonl((u_int32_t) ct->status);
 107         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 108         return 0;
 109
 110 nfattr_failure:
 111         return -1;
 112 }
 113
 114 static inline int
 115 ctnetlink_dump_timeout(struct sk_buff *skb, const struct ip_conntrack *ct)
 116 {
 117         long timeout_l = ct->timeout.expires - jiffies;
 118         __be32 timeout;
 119
 120         if (timeout_l < 0)
 121                 timeout = 0;
 122         else
 123                 timeout = htonl(timeout_l / HZ);
 124
 125         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 126         return 0;
 127
 128 nfattr_failure:
 129         return -1;
 130 }
 131
 132 static inline int
 133 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct ip_conntrack *ct)
 134 {
 135         struct ip_conntrack_protocol *proto = ip_conntrack_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 136
 137         struct nfattr *nest_proto;
 138         int ret;
 139
 140         if (!proto->to_nfattr) {
 141                 ip_conntrack_proto_put(proto);
 142                 return 0;
 143         }
 144
 145         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 146
 147         ret = proto->to_nfattr(skb, nest_proto, ct);
 148
 149         ip_conntrack_proto_put(proto);
 150
 151         NFA_NEST_END(skb, nest_proto);
 152
 153         return ret;
 154
 155 nfattr_failure:
 156         ip_conntrack_proto_put(proto);
 157         return -1;
 158 }
 159
 160 static inline int
 161 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct ip_conntrack *ct)
 162 {
 163         struct nfattr *nest_helper;
 164
 165         if (!ct->helper)
 166                 return 0;
 167
 168         nest_helper = NFA_NEST(skb, CTA_HELP);
 169         NFA_PUT(skb, CTA_HELP_NAME, strlen(ct->helper->name), ct->helper->name);
 170
 171         if (ct->helper->to_nfattr)
 172                 ct->helper->to_nfattr(skb, ct);
 173
 174         NFA_NEST_END(skb, nest_helper);
 175
 176         return 0;
 177
 178 nfattr_failure:
 179         return -1;
 180 }
 181
 182 #ifdef CONFIG_IP_NF_CT_ACCT
 183 static inline int
 184 ctnetlink_dump_counters(struct sk_buff *skb, const struct ip_conntrack *ct,
 185                         enum ip_conntrack_dir dir)
 186 {
 187         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 188         struct nfattr *nest_count = NFA_NEST(skb, type);
 189         __be32 tmp;
 190
 191         tmp = htonl(ct->counters[dir].packets);
 192         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(__be32), &tmp);
 193
 194         tmp = htonl(ct->counters[dir].bytes);
 195         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(__be32), &tmp);
 196
 197         NFA_NEST_END(skb, nest_count);
 198
 199         return 0;
 200
 201 nfattr_failure:
 202         return -1;
 203 }
 204 #else
 205 #define ctnetlink_dump_counters(a, b, c) (0)
 206 #endif
 207
 208 #ifdef CONFIG_IP_NF_CONNTRACK_MARK
 209 static inline int
 210 ctnetlink_dump_mark(struct sk_buff *skb, const struct ip_conntrack *ct)
 211 {
 212         __be32 mark = htonl(ct->mark);
 213
 214         NFA_PUT(skb, CTA_MARK, sizeof(__be32), &mark);
 215         return 0;
 216
 217 nfattr_failure:
 218         return -1;
 219 }
 220 #else
 221 #define ctnetlink_dump_mark(a, b) (0)
 222 #endif
 223
 224 static inline int
 225 ctnetlink_dump_id(struct sk_buff *skb, const struct ip_conntrack *ct)
 226 {
 227         __be32 id = htonl(ct->id);
 228         NFA_PUT(skb, CTA_ID, sizeof(__be32), &id);
 229         return 0;
 230
 231 nfattr_failure:
 232         return -1;
 233 }
 234
 235 static inline int
 236 ctnetlink_dump_use(struct sk_buff *skb, const struct ip_conntrack *ct)
 237 {
 238         __be32 use = htonl(atomic_read(&ct->ct_general.use));
 239
 240         NFA_PUT(skb, CTA_USE, sizeof(__be32), &use);
 241         return 0;
 242
 243 nfattr_failure:
 244         return -1;
 245 }
 246
 247 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 248
 249 static int
 250 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 251                     int event, int nowait,
 252                     const struct ip_conntrack *ct)
 253 {
 254         struct nlmsghdr *nlh;
 255         struct nfgenmsg *nfmsg;
 256         struct nfattr *nest_parms;
 257         unsigned char *b;
 258
 259         b = skb->tail;
 260
 261         event |= NFNL_SUBSYS_CTNETLINK << 8;
 262         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 263         nfmsg  = NLMSG_DATA(nlh);
 264
 265         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 266         nfmsg->nfgen_family = AF_INET;
 267         nfmsg->version      = NFNETLINK_V0;
 268         nfmsg->res_id       = 0;
 269
 270         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 271         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 272                 goto nfattr_failure;
 273         NFA_NEST_END(skb, nest_parms);
 274
 275         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 276         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 277                 goto nfattr_failure;
 278         NFA_NEST_END(skb, nest_parms);
 279
 280         if (ctnetlink_dump_status(skb, ct) < 0 ||
 281             ctnetlink_dump_timeout(skb, ct) < 0 ||
 282             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 283             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 284             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 285             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 286             ctnetlink_dump_mark(skb, ct) < 0 ||
 287             ctnetlink_dump_id(skb, ct) < 0 ||
 288             ctnetlink_dump_use(skb, ct) < 0)
 289                 goto nfattr_failure;
 290
 291         nlh->nlmsg_len = skb->tail - b;
 292         return skb->len;
 293
 294 nlmsg_failure:
 295 nfattr_failure:
 296         skb_trim(skb, b - skb->data);
 297         return -1;
 298 }
 299
 300 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
 301 static int ctnetlink_conntrack_event(struct notifier_block *this,
 302                                      unsigned long events, void *ptr)
 303 {
 304         struct nlmsghdr *nlh;
 305         struct nfgenmsg *nfmsg;
 306         struct nfattr *nest_parms;
 307         struct ip_conntrack *ct = (struct ip_conntrack *)ptr;
 308         struct sk_buff *skb;
 309         unsigned int type;
 310         unsigned char *b;
 311         unsigned int flags = 0, group;
 312
 313         /* ignore our fake conntrack entry */
 314         if (ct == &ip_conntrack_untracked)
 315                 return NOTIFY_DONE;
 316
 317         if (events & IPCT_DESTROY) {
 318                 type = IPCTNL_MSG_CT_DELETE;
 319                 group = NFNLGRP_CONNTRACK_DESTROY;
 320         } else if (events & (IPCT_NEW | IPCT_RELATED)) {
 321                 type = IPCTNL_MSG_CT_NEW;
 322                 flags = NLM_F_CREATE|NLM_F_EXCL;
 323                 group = NFNLGRP_CONNTRACK_NEW;
 324         } else if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 325                 type = IPCTNL_MSG_CT_NEW;
 326                 group = NFNLGRP_CONNTRACK_UPDATE;
 327         } else
 328                 return NOTIFY_DONE;
 329
 330         if (!nfnetlink_has_listeners(group))
 331                 return NOTIFY_DONE;
 332
 333         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 334         if (!skb)
 335                 return NOTIFY_DONE;
 336
 337         b = skb->tail;
 338
 339         type |= NFNL_SUBSYS_CTNETLINK << 8;
 340         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 341         nfmsg = NLMSG_DATA(nlh);
 342
 343         nlh->nlmsg_flags    = flags;
 344         nfmsg->nfgen_family = AF_INET;
 345         nfmsg->version  = NFNETLINK_V0;
 346         nfmsg->res_id   = 0;
 347
 348         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 349         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 350                 goto nfattr_failure;
 351         NFA_NEST_END(skb, nest_parms);
 352
 353         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 354         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 355                 goto nfattr_failure;
 356         NFA_NEST_END(skb, nest_parms);
 357
 358         if (events & IPCT_DESTROY) {
 359                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 360                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 361                         goto nfattr_failure;
 362         } else {
 363                 if (ctnetlink_dump_status(skb, ct) < 0)
 364                         goto nfattr_failure;
 365
 366                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 367                         goto nfattr_failure;
 368
 369                 if (events & IPCT_PROTOINFO
 370                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 371                         goto nfattr_failure;
 372
 373                 if ((events & IPCT_HELPER || ct->helper)
 374                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 375                         goto nfattr_failure;
 376
 377 #ifdef CONFIG_IP_NF_CONNTRACK_MARK
 378                 if ((events & IPCT_MARK || ct->mark)
 379                     && ctnetlink_dump_mark(skb, ct) < 0)
 380                         goto nfattr_failure;
 381 #endif
 382
 383                 if (events & IPCT_COUNTER_FILLING &&
 384                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 385                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
 386                         goto nfattr_failure;
 387         }
 388
 389         nlh->nlmsg_len = skb->tail - b;
 390         nfnetlink_send(skb, 0, group, 0);
 391         return NOTIFY_DONE;
 392
 393 nlmsg_failure:
 394 nfattr_failure:
 395         kfree_skb(skb);
 396         return NOTIFY_DONE;
 397 }
 398 #endif /* CONFIG_IP_NF_CONNTRACK_EVENTS */
 399
 400 static int ctnetlink_done(struct netlink_callback *cb)
 401 {
 402         if (cb->args[1])
 403                 ip_conntrack_put((struct ip_conntrack *)cb->args[1]);
 404         return 0;
 405 }
 406
 407 static int
 408 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 409 {
 410         struct ip_conntrack *ct, *last;
 411         struct ip_conntrack_tuple_hash *h;
 412         struct list_head *i;
 413
 414         read_lock_bh(&ip_conntrack_lock);
 415         last = (struct ip_conntrack *)cb->args[1];
 416         for (; cb->args[0] < ip_conntrack_htable_size; cb->args[0]++) {
 417 restart:
 418                 list_for_each_prev(i, &ip_conntrack_hash[cb->args[0]]) {
 419                         h = (struct ip_conntrack_tuple_hash *) i;
 420                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 421                                 continue;
 422                         ct = tuplehash_to_ctrack(h);
 423                         if (cb->args[1]) {
 424                                 if (ct != last)
 425                                         continue;
 426                                 cb->args[1] = 0;
 427                         }
 428                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 429                                                 cb->nlh->nlmsg_seq,
 430                                                 IPCTNL_MSG_CT_NEW,
 431                                                 1, ct) < 0) {
 432                                 nf_conntrack_get(&ct->ct_general);
 433                                 cb->args[1] = (unsigned long)ct;
 434                                 goto out;
 435                         }
 436 #ifdef CONFIG_NF_CT_ACCT
 437                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 438                                                 IPCTNL_MSG_CT_GET_CTRZERO)
 439                                 memset(&ct->counters, 0, sizeof(ct->counters));
 440 #endif
 441                 }
 442                 if (cb->args[1]) {
 443                         cb->args[1] = 0;
 444                         goto restart;
 445                 }
 446         }
 447 out:
 448         read_unlock_bh(&ip_conntrack_lock);
 449         if (last)
 450                 ip_conntrack_put(last);
 451
 452         return skb->len;
 453 }
 454
 455 static const size_t cta_min_ip[CTA_IP_MAX] = {
 456         [CTA_IP_V4_SRC-1]       = sizeof(__be32),
 457         [CTA_IP_V4_DST-1]       = sizeof(__be32),
 458 };
 459
 460 static inline int
 461 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct ip_conntrack_tuple *tuple)
 462 {
 463         struct nfattr *tb[CTA_IP_MAX];
 464
 465         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 466
 467         if (nfattr_bad_size(tb, CTA_IP_MAX, cta_min_ip))
 468                 return -EINVAL;
 469
 470         if (!tb[CTA_IP_V4_SRC-1])
 471                 return -EINVAL;
 472         tuple->src.ip = *(__be32 *)NFA_DATA(tb[CTA_IP_V4_SRC-1]);
 473
 474         if (!tb[CTA_IP_V4_DST-1])
 475                 return -EINVAL;
 476         tuple->dst.ip = *(__be32 *)NFA_DATA(tb[CTA_IP_V4_DST-1]);
 477
 478         return 0;
 479 }
 480
 481 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 482         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 483         [CTA_PROTO_SRC_PORT-1]  = sizeof(u_int16_t),
 484         [CTA_PROTO_DST_PORT-1]  = sizeof(u_int16_t),
 485         [CTA_PROTO_ICMP_TYPE-1] = sizeof(u_int8_t),
 486         [CTA_PROTO_ICMP_CODE-1] = sizeof(u_int8_t),
 487         [CTA_PROTO_ICMP_ID-1]   = sizeof(u_int16_t),
 488 };
 489
 490 static inline int
 491 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 492                             struct ip_conntrack_tuple *tuple)
 493 {
 494         struct nfattr *tb[CTA_PROTO_MAX];
 495         struct ip_conntrack_protocol *proto;
 496         int ret = 0;
 497
 498         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 499
 500         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 501                 return -EINVAL;
 502
 503         if (!tb[CTA_PROTO_NUM-1])
 504                 return -EINVAL;
 505         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 506
 507         proto = ip_conntrack_proto_find_get(tuple->dst.protonum);
 508
 509         if (likely(proto->nfattr_to_tuple))
 510                 ret = proto->nfattr_to_tuple(tb, tuple);
 511
 512         ip_conntrack_proto_put(proto);
 513
 514         return ret;
 515 }
 516
 517 static inline int
 518 ctnetlink_parse_tuple(struct nfattr *cda[], struct ip_conntrack_tuple *tuple,
 519                       enum ctattr_tuple type)
 520 {
 521         struct nfattr *tb[CTA_TUPLE_MAX];
 522         int err;
 523
 524         memset(tuple, 0, sizeof(*tuple));
 525
 526         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 527
 528         if (!tb[CTA_TUPLE_IP-1])
 529                 return -EINVAL;
 530
 531         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 532         if (err < 0)
 533                 return err;
 534
 535         if (!tb[CTA_TUPLE_PROTO-1])
 536                 return -EINVAL;
 537
 538         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 539         if (err < 0)
 540                 return err;
 541
 542         /* orig and expect tuples get DIR_ORIGINAL */
 543         if (type == CTA_TUPLE_REPLY)
 544                 tuple->dst.dir = IP_CT_DIR_REPLY;
 545         else
 546                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 547
 548         return 0;
 549 }
 550
 551 #ifdef CONFIG_IP_NF_NAT_NEEDED
 552 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 553         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 554         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 555 };
 556
 557 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 558                                      const struct ip_conntrack *ct,
 559                                      struct ip_nat_range *range)
 560 {
 561         struct nfattr *tb[CTA_PROTONAT_MAX];
 562         struct ip_nat_protocol *npt;
 563
 564         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 565
 566         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 567                 return -EINVAL;
 568
 569         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 570
 571         if (!npt->nfattr_to_range) {
 572                 ip_nat_proto_put(npt);
 573                 return 0;
 574         }
 575
 576         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 577         if (npt->nfattr_to_range(tb, range) > 0)
 578                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 579
 580         ip_nat_proto_put(npt);
 581
 582         return 0;
 583 }
 584
 585 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 586         [CTA_NAT_MINIP-1]       = sizeof(__be32),
 587         [CTA_NAT_MAXIP-1]       = sizeof(__be32),
 588 };
 589
 590 static inline int
 591 ctnetlink_parse_nat(struct nfattr *nat,
 592                     const struct ip_conntrack *ct, struct ip_nat_range *range)
 593 {
 594         struct nfattr *tb[CTA_NAT_MAX];
 595         int err;
 596
 597         memset(range, 0, sizeof(*range));
 598
 599         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 600
 601         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 602                 return -EINVAL;
 603
 604         if (tb[CTA_NAT_MINIP-1])
 605                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 606
 607         if (!tb[CTA_NAT_MAXIP-1])
 608                 range->max_ip = range->min_ip;
 609         else
 610                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 611
 612         if (range->min_ip)
 613                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 614
 615         if (!tb[CTA_NAT_PROTO-1])
 616                 return 0;
 617
 618         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 619         if (err < 0)
 620                 return err;
 621
 622         return 0;
 623 }
 624 #endif
 625
 626 static inline int
 627 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 628 {
 629         struct nfattr *tb[CTA_HELP_MAX];
 630
 631         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 632
 633         if (!tb[CTA_HELP_NAME-1])
 634                 return -EINVAL;
 635
 636         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 637
 638         return 0;
 639 }
 640
 641 static const size_t cta_min[CTA_MAX] = {
 642         [CTA_STATUS-1]          = sizeof(__be32),
 643         [CTA_TIMEOUT-1]         = sizeof(__be32),
 644         [CTA_MARK-1]            = sizeof(__be32),
 645         [CTA_USE-1]             = sizeof(__be32),
 646         [CTA_ID-1]              = sizeof(__be32)
 647 };
 648
 649 static int
 650 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 651                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 652 {
 653         struct ip_conntrack_tuple_hash *h;
 654         struct ip_conntrack_tuple tuple;
 655         struct ip_conntrack *ct;
 656         int err = 0;
 657
 658         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 659                 return -EINVAL;
 660
 661         if (cda[CTA_TUPLE_ORIG-1])
 662                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG);
 663         else if (cda[CTA_TUPLE_REPLY-1])
 664                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY);
 665         else {
 666                 /* Flush the whole table */
 667                 ip_conntrack_flush();
 668                 return 0;
 669         }
 670
 671         if (err < 0)
 672                 return err;
 673
 674         h = ip_conntrack_find_get(&tuple, NULL);
 675         if (!h)
 676                 return -ENOENT;
 677
 678         ct = tuplehash_to_ctrack(h);
 679
 680         if (cda[CTA_ID-1]) {
 681                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
 682                 if (ct->id != id) {
 683                         ip_conntrack_put(ct);
 684                         return -ENOENT;
 685                 }
 686         }
 687         if (del_timer(&ct->timeout))
 688                 ct->timeout.function((unsigned long)ct);
 689
 690         ip_conntrack_put(ct);
 691
 692         return 0;
 693 }
 694
 695 static int
 696 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 697                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 698 {
 699         struct ip_conntrack_tuple_hash *h;
 700         struct ip_conntrack_tuple tuple;
 701         struct ip_conntrack *ct;
 702         struct sk_buff *skb2 = NULL;
 703         int err = 0;
 704
 705         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 706                 struct nfgenmsg *msg = NLMSG_DATA(nlh);
 707                 u32 rlen;
 708
 709                 if (msg->nfgen_family != AF_INET)
 710                         return -EAFNOSUPPORT;
 711
 712 #ifndef CONFIG_IP_NF_CT_ACCT
 713                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
 714                         return -ENOTSUPP;
 715 #endif
 716                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 717                                                 ctnetlink_dump_table,
 718                                                 ctnetlink_done)) != 0)
 719                         return -EINVAL;
 720
 721                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 722                 if (rlen > skb->len)
 723                         rlen = skb->len;
 724                 skb_pull(skb, rlen);
 725                 return 0;
 726         }
 727
 728         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 729                 return -EINVAL;
 730
 731         if (cda[CTA_TUPLE_ORIG-1])
 732                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG);
 733         else if (cda[CTA_TUPLE_REPLY-1])
 734                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY);
 735         else
 736                 return -EINVAL;
 737
 738         if (err < 0)
 739                 return err;
 740
 741         h = ip_conntrack_find_get(&tuple, NULL);
 742         if (!h)
 743                 return -ENOENT;
 744
 745         ct = tuplehash_to_ctrack(h);
 746
 747         err = -ENOMEM;
 748         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 749         if (!skb2) {
 750                 ip_conntrack_put(ct);
 751                 return -ENOMEM;
 752         }
 753
 754         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 755                                   IPCTNL_MSG_CT_NEW, 1, ct);
 756         ip_conntrack_put(ct);
 757         if (err <= 0)
 758                 goto free;
 759
 760         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 761         if (err < 0)
 762                 goto out;
 763
 764         return 0;
 765
 766 free:
 767         kfree_skb(skb2);
 768 out:
 769         return err;
 770 }
 771
 772 static inline int
 773 ctnetlink_change_status(struct ip_conntrack *ct, struct nfattr *cda[])
 774 {
 775         unsigned long d;
 776         unsigned status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));
 777         d = ct->status ^ status;
 778
 779         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 780                 /* unchangeable */
 781                 return -EINVAL;
 782
 783         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 784                 /* SEEN_REPLY bit can only be set */
 785                 return -EINVAL;
 786
 787
 788         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 789                 /* ASSURED bit can only be set */
 790                 return -EINVAL;
 791
 792         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 793 #ifndef CONFIG_IP_NF_NAT_NEEDED
 794                 return -EINVAL;
 795 #else
 796                 struct ip_nat_range range;
 797
 798                 if (cda[CTA_NAT_DST-1]) {
 799                         if (ctnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 800                                                 &range) < 0)
 801                                 return -EINVAL;
 802                         if (ip_nat_initialized(ct,
 803                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 804                                 return -EEXIST;
 805                         ip_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
 806                 }
 807                 if (cda[CTA_NAT_SRC-1]) {
 808                         if (ctnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 809                                                 &range) < 0)
 810                                 return -EINVAL;
 811                         if (ip_nat_initialized(ct,
 812                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 813                                 return -EEXIST;
 814                         ip_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
 815                 }
 816 #endif
 817         }
 818
 819         /* Be careful here, modifying NAT bits can screw up things,
 820          * so don't let users modify them directly if they don't pass
 821          * ip_nat_range. */
 822         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 823         return 0;
 824 }
 825
 826
 827 static inline int
 828 ctnetlink_change_helper(struct ip_conntrack *ct, struct nfattr *cda[])
 829 {
 830         struct ip_conntrack_helper *helper;
 831         char *helpname;
 832         int err;
 833
 834         /* don't change helper of sibling connections */
 835         if (ct->master)
 836                 return -EINVAL;
 837
 838         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 839         if (err < 0)
 840                 return err;
 841
 842         helper = __ip_conntrack_helper_find_byname(helpname);
 843         if (!helper) {
 844                 if (!strcmp(helpname, ""))
 845                         helper = NULL;
 846                 else
 847                         return -EINVAL;
 848         }
 849
 850         if (ct->helper) {
 851                 if (!helper) {
 852                         /* we had a helper before ... */
 853                         ip_ct_remove_expectations(ct);
 854                         ct->helper = NULL;
 855                 } else {
 856                         /* need to zero data of old helper */
 857                         memset(&ct->help, 0, sizeof(ct->help));
 858                 }
 859         }
 860
 861         ct->helper = helper;
 862
 863         return 0;
 864 }
 865
 866 static inline int
 867 ctnetlink_change_timeout(struct ip_conntrack *ct, struct nfattr *cda[])
 868 {
 869         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 870
 871         if (!del_timer(&ct->timeout))
 872                 return -ETIME;
 873
 874         ct->timeout.expires = jiffies + timeout * HZ;
 875         add_timer(&ct->timeout);
 876
 877         return 0;
 878 }
 879
 880 static inline int
 881 ctnetlink_change_protoinfo(struct ip_conntrack *ct, struct nfattr *cda[])
 882 {
 883         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 884         struct ip_conntrack_protocol *proto;
 885         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 886         int err = 0;
 887
 888         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 889
 890         proto = ip_conntrack_proto_find_get(npt);
 891
 892         if (proto->from_nfattr)
 893                 err = proto->from_nfattr(tb, ct);
 894         ip_conntrack_proto_put(proto);
 895
 896         return err;
 897 }
 898
 899 static int
 900 ctnetlink_change_conntrack(struct ip_conntrack *ct, struct nfattr *cda[])
 901 {
 902         int err;
 903
 904         if (cda[CTA_HELP-1]) {
 905                 err = ctnetlink_change_helper(ct, cda);
 906                 if (err < 0)
 907                         return err;
 908         }
 909
 910         if (cda[CTA_TIMEOUT-1]) {
 911                 err = ctnetlink_change_timeout(ct, cda);
 912                 if (err < 0)
 913                         return err;
 914         }
 915
 916         if (cda[CTA_STATUS-1]) {
 917                 err = ctnetlink_change_status(ct, cda);
 918                 if (err < 0)
 919                         return err;
 920         }
 921
 922         if (cda[CTA_PROTOINFO-1]) {
 923                 err = ctnetlink_change_protoinfo(ct, cda);
 924                 if (err < 0)
 925                         return err;
 926         }
 927
 928 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
 929         if (cda[CTA_MARK-1])
 930                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 931 #endif
 932
 933         return 0;
 934 }
 935
 936 static int
 937 ctnetlink_create_conntrack(struct nfattr *cda[],
 938                            struct ip_conntrack_tuple *otuple,
 939                            struct ip_conntrack_tuple *rtuple)
 940 {
 941         struct ip_conntrack *ct;
 942         int err = -EINVAL;
 943
 944         ct = ip_conntrack_alloc(otuple, rtuple);
 945         if (ct == NULL || IS_ERR(ct))
 946                 return -ENOMEM;
 947
 948         if (!cda[CTA_TIMEOUT-1])
 949                 goto err;
 950         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 951
 952         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
 953         ct->status |= IPS_CONFIRMED;
 954
 955         if (cda[CTA_STATUS-1]) {
 956                 err = ctnetlink_change_status(ct, cda);
 957                 if (err < 0)
 958                         goto err;
 959         }
 960
 961         if (cda[CTA_PROTOINFO-1]) {
 962                 err = ctnetlink_change_protoinfo(ct, cda);
 963                 if (err < 0)
 964                         goto err;
 965         }
 966
 967 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
 968         if (cda[CTA_MARK-1])
 969                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 970 #endif
 971
 972         ct->helper = ip_conntrack_helper_find_get(rtuple);
 973
 974         add_timer(&ct->timeout);
 975         ip_conntrack_hash_insert(ct);
 976
 977         if (ct->helper)
 978                 ip_conntrack_helper_put(ct->helper);
 979
 980         return 0;
 981
 982 err:
 983         ip_conntrack_free(ct);
 984         return err;
 985 }
 986
 987 static int
 988 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
 989                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 990 {
 991         struct ip_conntrack_tuple otuple, rtuple;
 992         struct ip_conntrack_tuple_hash *h = NULL;
 993         int err = 0;
 994
 995         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 996                 return -EINVAL;
 997
 998         if (cda[CTA_TUPLE_ORIG-1]) {
 999                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG);
1000                 if (err < 0)
1001                         return err;
1002         }
1003
1004         if (cda[CTA_TUPLE_REPLY-1]) {
1005                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY);
1006                 if (err < 0)
1007                         return err;
1008         }
1009
1010         write_lock_bh(&ip_conntrack_lock);
1011         if (cda[CTA_TUPLE_ORIG-1])
1012                 h = __ip_conntrack_find(&otuple, NULL);
1013         else if (cda[CTA_TUPLE_REPLY-1])
1014                 h = __ip_conntrack_find(&rtuple, NULL);
1015
1016         if (h == NULL) {
1017                 write_unlock_bh(&ip_conntrack_lock);
1018                 err = -ENOENT;
1019                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1020                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1021                 return err;
1022         }
1023         /* implicit 'else' */
1024
1025         /* we only allow nat config for new conntracks */
1026         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1027                 err = -EINVAL;
1028                 goto out_unlock;
1029         }
1030
1031         /* We manipulate the conntrack inside the global conntrack table lock,
1032          * so there's no need to increase the refcount */
1033         err = -EEXIST;
1034         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1035                 err = ctnetlink_change_conntrack(tuplehash_to_ctrack(h), cda);
1036
1037 out_unlock:
1038         write_unlock_bh(&ip_conntrack_lock);
1039         return err;
1040 }
1041
1042 /***********************************************************************
1043  * EXPECT
1044  ***********************************************************************/
1045
1046 static inline int
1047 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1048                          const struct ip_conntrack_tuple *tuple,
1049                          enum ctattr_expect type)
1050 {
1051         struct nfattr *nest_parms = NFA_NEST(skb, type);
1052
1053         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1054                 goto nfattr_failure;
1055
1056         NFA_NEST_END(skb, nest_parms);
1057
1058         return 0;
1059
1060 nfattr_failure:
1061         return -1;
1062 }
1063
1064 static inline int
1065 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1066                         const struct ip_conntrack_tuple *tuple,
1067                         const struct ip_conntrack_tuple *mask)
1068 {
1069         int ret;
1070         struct ip_conntrack_protocol *proto;
1071         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1072
1073         ret = ctnetlink_dump_tuples_ip(skb, mask);
1074         if (unlikely(ret < 0))
1075                 goto nfattr_failure;
1076
1077         proto = ip_conntrack_proto_find_get(tuple->dst.protonum);
1078         ret = ctnetlink_dump_tuples_proto(skb, mask, proto);
1079         ip_conntrack_proto_put(proto);
1080         if (unlikely(ret < 0))
1081                 goto nfattr_failure;
1082
1083         NFA_NEST_END(skb, nest_parms);
1084
1085         return 0;
1086
1087 nfattr_failure:
1088         return -1;
1089 }
1090
1091 static inline int
1092 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1093                           const struct ip_conntrack_expect *exp)
1094 {
1095         struct ip_conntrack *master = exp->master;
1096         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1097         __be32 id = htonl(exp->id);
1098
1099         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1100                 goto nfattr_failure;
1101         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1102                 goto nfattr_failure;
1103         if (ctnetlink_exp_dump_tuple(skb,
1104                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1105                                  CTA_EXPECT_MASTER) < 0)
1106                 goto nfattr_failure;
1107
1108         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(__be32), &timeout);
1109         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(__be32), &id);
1110
1111         return 0;
1112
1113 nfattr_failure:
1114         return -1;
1115 }
1116
1117 static int
1118 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1119                     int event,
1120                     int nowait,
1121                     const struct ip_conntrack_expect *exp)
1122 {
1123         struct nlmsghdr *nlh;
1124         struct nfgenmsg *nfmsg;
1125         unsigned char *b;
1126
1127         b = skb->tail;
1128
1129         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1130         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1131         nfmsg  = NLMSG_DATA(nlh);
1132
1133         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1134         nfmsg->nfgen_family = AF_INET;
1135         nfmsg->version      = NFNETLINK_V0;
1136         nfmsg->res_id       = 0;
1137
1138         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1139                 goto nfattr_failure;
1140
1141         nlh->nlmsg_len = skb->tail - b;
1142         return skb->len;
1143
1144 nlmsg_failure:
1145 nfattr_failure:
1146         skb_trim(skb, b - skb->data);
1147         return -1;
1148 }
1149
1150 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1151 static int ctnetlink_expect_event(struct notifier_block *this,
1152                                   unsigned long events, void *ptr)
1153 {
1154         struct nlmsghdr *nlh;
1155         struct nfgenmsg *nfmsg;
1156         struct ip_conntrack_expect *exp = (struct ip_conntrack_expect *)ptr;
1157         struct sk_buff *skb;
1158         unsigned int type;
1159         unsigned char *b;
1160         int flags = 0;
1161
1162         if (events & IPEXP_NEW) {
1163                 type = IPCTNL_MSG_EXP_NEW;
1164                 flags = NLM_F_CREATE|NLM_F_EXCL;
1165         } else
1166                 return NOTIFY_DONE;
1167
1168         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1169                 return NOTIFY_DONE;
1170
1171         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1172         if (!skb)
1173                 return NOTIFY_DONE;
1174
1175         b = skb->tail;
1176
1177         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1178         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1179         nfmsg = NLMSG_DATA(nlh);
1180
1181         nlh->nlmsg_flags    = flags;
1182         nfmsg->nfgen_family = AF_INET;
1183         nfmsg->version      = NFNETLINK_V0;
1184         nfmsg->res_id       = 0;
1185
1186         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1187                 goto nfattr_failure;
1188
1189         nlh->nlmsg_len = skb->tail - b;
1190         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1191         return NOTIFY_DONE;
1192
1193 nlmsg_failure:
1194 nfattr_failure:
1195         kfree_skb(skb);
1196         return NOTIFY_DONE;
1197 }
1198 #endif
1199
1200 static int
1201 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1202 {
1203         struct ip_conntrack_expect *exp = NULL;
1204         struct list_head *i;
1205         u_int32_t *id = (u_int32_t *) &cb->args[0];
1206
1207         read_lock_bh(&ip_conntrack_lock);
1208         list_for_each_prev(i, &ip_conntrack_expect_list) {
1209                 exp = (struct ip_conntrack_expect *) i;
1210                 if (exp->id <= *id)
1211                         continue;
1212                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1213                                             cb->nlh->nlmsg_seq,
1214                                             IPCTNL_MSG_EXP_NEW,
1215                                             1, exp) < 0)
1216                         goto out;
1217                 *id = exp->id;
1218         }
1219 out:
1220         read_unlock_bh(&ip_conntrack_lock);
1221
1222         return skb->len;
1223 }
1224
1225 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1226         [CTA_EXPECT_TIMEOUT-1]          = sizeof(__be32),
1227         [CTA_EXPECT_ID-1]               = sizeof(__be32)
1228 };
1229
1230 static int
1231 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1232                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1233 {
1234         struct ip_conntrack_tuple tuple;
1235         struct ip_conntrack_expect *exp;
1236         struct sk_buff *skb2;
1237         int err = 0;
1238
1239         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1240                 return -EINVAL;
1241
1242         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1243                 struct nfgenmsg *msg = NLMSG_DATA(nlh);
1244                 u32 rlen;
1245
1246                 if (msg->nfgen_family != AF_INET)
1247                         return -EAFNOSUPPORT;
1248
1249                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1250                                                 ctnetlink_exp_dump_table,
1251                                                 ctnetlink_done)) != 0)
1252                         return -EINVAL;
1253                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1254                 if (rlen > skb->len)
1255                         rlen = skb->len;
1256                 skb_pull(skb, rlen);
1257                 return 0;
1258         }
1259
1260         if (cda[CTA_EXPECT_MASTER-1])
1261                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER);
1262         else
1263                 return -EINVAL;
1264
1265         if (err < 0)
1266                 return err;
1267
1268         exp = ip_conntrack_expect_find_get(&tuple);
1269         if (!exp)
1270                 return -ENOENT;
1271
1272         if (cda[CTA_EXPECT_ID-1]) {
1273                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1274                 if (exp->id != ntohl(id)) {
1275                         ip_conntrack_expect_put(exp);
1276                         return -ENOENT;
1277                 }
1278         }
1279
1280         err = -ENOMEM;
1281         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1282         if (!skb2)
1283                 goto out;
1284
1285         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1286                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1287                                       1, exp);
1288         if (err <= 0)
1289                 goto free;
1290
1291         ip_conntrack_expect_put(exp);
1292
1293         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1294
1295 free:
1296         kfree_skb(skb2);
1297 out:
1298         ip_conntrack_expect_put(exp);
1299         return err;
1300 }
1301
1302 static int
1303 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1304                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1305 {
1306         struct ip_conntrack_expect *exp, *tmp;
1307         struct ip_conntrack_tuple tuple;
1308         struct ip_conntrack_helper *h;
1309         int err;
1310
1311         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1312                 return -EINVAL;
1313
1314         if (cda[CTA_EXPECT_TUPLE-1]) {
1315                 /* delete a single expect by tuple */
1316                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE);
1317                 if (err < 0)
1318                         return err;
1319
1320                 /* bump usage count to 2 */
1321                 exp = ip_conntrack_expect_find_get(&tuple);
1322                 if (!exp)
1323                         return -ENOENT;
1324
1325                 if (cda[CTA_EXPECT_ID-1]) {
1326                         __be32 id =
1327                                 *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1328                         if (exp->id != ntohl(id)) {
1329                                 ip_conntrack_expect_put(exp);
1330                                 return -ENOENT;
1331                         }
1332                 }
1333
1334                 /* after list removal, usage count == 1 */
1335                 ip_conntrack_unexpect_related(exp);
1336                 /* have to put what we 'get' above.
1337                  * after this line usage count == 0 */
1338                 ip_conntrack_expect_put(exp);
1339         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1340                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1341
1342                 /* delete all expectations for this helper */
1343                 write_lock_bh(&ip_conntrack_lock);
1344                 h = __ip_conntrack_helper_find_byname(name);
1345                 if (!h) {
1346                         write_unlock_bh(&ip_conntrack_lock);
1347                         return -EINVAL;
1348                 }
1349                 list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list,
1350                                          list) {
1351                         if (exp->master->helper == h
1352                             && del_timer(&exp->timeout)) {
1353                                 ip_ct_unlink_expect(exp);
1354                                 ip_conntrack_expect_put(exp);
1355                         }
1356                 }
1357                 write_unlock_bh(&ip_conntrack_lock);
1358         } else {
1359                 /* This basically means we have to flush everything*/
1360                 write_lock_bh(&ip_conntrack_lock);
1361                 list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list,
1362                                          list) {
1363                         if (del_timer(&exp->timeout)) {
1364                                 ip_ct_unlink_expect(exp);
1365                                 ip_conntrack_expect_put(exp);
1366                         }
1367                 }
1368                 write_unlock_bh(&ip_conntrack_lock);
1369         }
1370
1371         return 0;
1372 }
1373 static int
1374 ctnetlink_change_expect(struct ip_conntrack_expect *x, struct nfattr *cda[])
1375 {
1376         return -EOPNOTSUPP;
1377 }
1378
1379 static int
1380 ctnetlink_create_expect(struct nfattr *cda[])
1381 {
1382         struct ip_conntrack_tuple tuple, mask, master_tuple;
1383         struct ip_conntrack_tuple_hash *h = NULL;
1384         struct ip_conntrack_expect *exp;
1385         struct ip_conntrack *ct;
1386         int err = 0;
1387
1388         /* caller guarantees that those three CTA_EXPECT_* exist */
1389         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE);
1390         if (err < 0)
1391                 return err;
1392         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK);
1393         if (err < 0)
1394                 return err;
1395         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER);
1396         if (err < 0)
1397                 return err;
1398
1399         /* Look for master conntrack of this expectation */
1400         h = ip_conntrack_find_get(&master_tuple, NULL);
1401         if (!h)
1402                 return -ENOENT;
1403         ct = tuplehash_to_ctrack(h);
1404
1405         if (!ct->helper) {
1406                 /* such conntrack hasn't got any helper, abort */
1407                 err = -EINVAL;
1408                 goto out;
1409         }
1410
1411         exp = ip_conntrack_expect_alloc(ct);
1412         if (!exp) {
1413                 err = -ENOMEM;
1414                 goto out;
1415         }
1416
1417         exp->expectfn = NULL;
1418         exp->flags = 0;
1419         exp->master = ct;
1420         memcpy(&exp->tuple, &tuple, sizeof(struct ip_conntrack_tuple));
1421         memcpy(&exp->mask, &mask, sizeof(struct ip_conntrack_tuple));
1422
1423         err = ip_conntrack_expect_related(exp);
1424         ip_conntrack_expect_put(exp);
1425
1426 out:
1427         ip_conntrack_put(tuplehash_to_ctrack(h));
1428         return err;
1429 }
1430
1431 static int
1432 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1433                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1434 {
1435         struct ip_conntrack_tuple tuple;
1436         struct ip_conntrack_expect *exp;
1437         int err = 0;
1438
1439         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1440                 return -EINVAL;
1441
1442         if (!cda[CTA_EXPECT_TUPLE-1]
1443             || !cda[CTA_EXPECT_MASK-1]
1444             || !cda[CTA_EXPECT_MASTER-1])
1445                 return -EINVAL;
1446
1447         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE);
1448         if (err < 0)
1449                 return err;
1450
1451         write_lock_bh(&ip_conntrack_lock);
1452         exp = __ip_conntrack_expect_find(&tuple);
1453
1454         if (!exp) {
1455                 write_unlock_bh(&ip_conntrack_lock);
1456                 err = -ENOENT;
1457                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1458                         err = ctnetlink_create_expect(cda);
1459                 return err;
1460         }
1461
1462         err = -EEXIST;
1463         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1464                 err = ctnetlink_change_expect(exp, cda);
1465         write_unlock_bh(&ip_conntrack_lock);
1466
1467         return err;
1468 }
1469
1470 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1471 static struct notifier_block ctnl_notifier = {
1472         .notifier_call  = ctnetlink_conntrack_event,
1473 };
1474
1475 static struct notifier_block ctnl_notifier_exp = {
1476         .notifier_call  = ctnetlink_expect_event,
1477 };
1478 #endif
1479
1480 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1481         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1482                                             .attr_count = CTA_MAX, },
1483         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1484                                             .attr_count = CTA_MAX, },
1485         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1486                                             .attr_count = CTA_MAX, },
1487         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1488                                             .attr_count = CTA_MAX, },
1489 };
1490
1491 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1492         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1493                                             .attr_count = CTA_EXPECT_MAX, },
1494         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1495                                             .attr_count = CTA_EXPECT_MAX, },
1496         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1497                                             .attr_count = CTA_EXPECT_MAX, },
1498 };
1499
1500 static struct nfnetlink_subsystem ctnl_subsys = {
1501         .name                           = "conntrack",
1502         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1503         .cb_count                       = IPCTNL_MSG_MAX,
1504         .cb                             = ctnl_cb,
1505 };
1506
1507 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1508         .name                           = "conntrack_expect",
1509         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1510         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1511         .cb                             = ctnl_exp_cb,
1512 };
1513
1514 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1515 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1516
1517 static int __init ctnetlink_init(void)
1518 {
1519         int ret;
1520
1521         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1522         ret = nfnetlink_subsys_register(&ctnl_subsys);
1523         if (ret < 0) {
1524                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1525                 goto err_out;
1526         }
1527
1528         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1529         if (ret < 0) {
1530                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1531                 goto err_unreg_subsys;
1532         }
1533
1534 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1535         ret = ip_conntrack_register_notifier(&ctnl_notifier);
1536         if (ret < 0) {
1537                 printk("ctnetlink_init: cannot register notifier.\n");
1538                 goto err_unreg_exp_subsys;
1539         }
1540
1541         ret = ip_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1542         if (ret < 0) {
1543                 printk("ctnetlink_init: cannot expect register notifier.\n");
1544                 goto err_unreg_notifier;
1545         }
1546 #endif
1547
1548         return 0;
1549
1550 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1551 err_unreg_notifier:
1552         ip_conntrack_unregister_notifier(&ctnl_notifier);
1553 err_unreg_exp_subsys:
1554         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1555 #endif
1556 err_unreg_subsys:
1557         nfnetlink_subsys_unregister(&ctnl_subsys);
1558 err_out:
1559         return ret;
1560 }
1561
1562 static void __exit ctnetlink_exit(void)
1563 {
1564         printk("ctnetlink: unregistering from nfnetlink.\n");
1565
1566 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1567         ip_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1568         ip_conntrack_unregister_notifier(&ctnl_notifier);
1569 #endif
1570
1571         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1572         nfnetlink_subsys_unregister(&ctnl_subsys);
1573         return;
1574 }
1575
1576 module_init(ctnetlink_init);
1577 module_exit(ctnetlink_exit);