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 #if 0
  48 #define DEBUGP printk
  49 #else
  50 #define DEBUGP(format, args...)
  51 #endif
  52
  53
  54 static inline int
  55 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  56                             const struct ip_conntrack_tuple *tuple,
  57                             struct ip_conntrack_protocol *proto)
  58 {
  59         int ret = 0;
  60         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  61
  62         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  63
  64         if (likely(proto->tuple_to_nfattr))
  65                 ret = proto->tuple_to_nfattr(skb, tuple);
  66
  67         NFA_NEST_END(skb, nest_parms);
  68
  69         return ret;
  70
  71 nfattr_failure:
  72         return -1;
  73 }
  74
  75 static inline int
  76 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  77                          const struct ip_conntrack_tuple *tuple)
  78 {
  79         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  80
  81         NFA_PUT(skb, CTA_IP_V4_SRC, sizeof(u_int32_t), &tuple->src.ip);
  82         NFA_PUT(skb, CTA_IP_V4_DST, sizeof(u_int32_t), &tuple->dst.ip);
  83
  84         NFA_NEST_END(skb, nest_parms);
  85
  86         return 0;
  87
  88 nfattr_failure:
  89         return -1;
  90 }
  91
  92 static inline int
  93 ctnetlink_dump_tuples(struct sk_buff *skb,
  94                       const struct ip_conntrack_tuple *tuple)
  95 {
  96         int ret;
  97         struct ip_conntrack_protocol *proto;
  98
  99         ret = ctnetlink_dump_tuples_ip(skb, tuple);
 100         if (unlikely(ret < 0))
 101                 return ret;
 102
 103         proto = ip_conntrack_proto_find_get(tuple->dst.protonum);
 104         ret = ctnetlink_dump_tuples_proto(skb, tuple, proto);
 105         ip_conntrack_proto_put(proto);
 106
 107         return ret;
 108 }
 109
 110 static inline int
 111 ctnetlink_dump_status(struct sk_buff *skb, const struct ip_conntrack *ct)
 112 {
 113         u_int32_t status = htonl((u_int32_t) ct->status);
 114         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 115         return 0;
 116
 117 nfattr_failure:
 118         return -1;
 119 }
 120
 121 static inline int
 122 ctnetlink_dump_timeout(struct sk_buff *skb, const struct ip_conntrack *ct)
 123 {
 124         long timeout_l = ct->timeout.expires - jiffies;
 125         u_int32_t timeout;
 126
 127         if (timeout_l < 0)
 128                 timeout = 0;
 129         else
 130                 timeout = htonl(timeout_l / HZ);
 131
 132         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 133         return 0;
 134
 135 nfattr_failure:
 136         return -1;
 137 }
 138
 139 static inline int
 140 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct ip_conntrack *ct)
 141 {
 142         struct ip_conntrack_protocol *proto = ip_conntrack_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 143
 144         struct nfattr *nest_proto;
 145         int ret;
 146
 147         if (!proto->to_nfattr) {
 148                 ip_conntrack_proto_put(proto);
 149                 return 0;
 150         }
 151
 152         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 153
 154         ret = proto->to_nfattr(skb, nest_proto, ct);
 155
 156         ip_conntrack_proto_put(proto);
 157
 158         NFA_NEST_END(skb, nest_proto);
 159
 160         return ret;
 161
 162 nfattr_failure:
 163         return -1;
 164 }
 165
 166 static inline int
 167 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct ip_conntrack *ct)
 168 {
 169         struct nfattr *nest_helper;
 170
 171         if (!ct->helper)
 172                 return 0;
 173
 174         nest_helper = NFA_NEST(skb, CTA_HELP);
 175         NFA_PUT(skb, CTA_HELP_NAME, strlen(ct->helper->name), ct->helper->name);
 176
 177         if (ct->helper->to_nfattr)
 178                 ct->helper->to_nfattr(skb, ct);
 179
 180         NFA_NEST_END(skb, nest_helper);
 181
 182         return 0;
 183
 184 nfattr_failure:
 185         return -1;
 186 }
 187
 188 #ifdef CONFIG_IP_NF_CT_ACCT
 189 static inline int
 190 ctnetlink_dump_counters(struct sk_buff *skb, const struct ip_conntrack *ct,
 191                         enum ip_conntrack_dir dir)
 192 {
 193         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 194         struct nfattr *nest_count = NFA_NEST(skb, type);
 195         u_int32_t tmp;
 196
 197         tmp = htonl(ct->counters[dir].packets);
 198         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 199
 200         tmp = htonl(ct->counters[dir].bytes);
 201         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 202
 203         NFA_NEST_END(skb, nest_count);
 204
 205         return 0;
 206
 207 nfattr_failure:
 208         return -1;
 209 }
 210 #else
 211 #define ctnetlink_dump_counters(a, b, c) (0)
 212 #endif
 213
 214 #ifdef CONFIG_IP_NF_CONNTRACK_MARK
 215 static inline int
 216 ctnetlink_dump_mark(struct sk_buff *skb, const struct ip_conntrack *ct)
 217 {
 218         u_int32_t mark = htonl(ct->mark);
 219
 220         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 221         return 0;
 222
 223 nfattr_failure:
 224         return -1;
 225 }
 226 #else
 227 #define ctnetlink_dump_mark(a, b) (0)
 228 #endif
 229
 230 static inline int
 231 ctnetlink_dump_id(struct sk_buff *skb, const struct ip_conntrack *ct)
 232 {
 233         u_int32_t id = htonl(ct->id);
 234         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 235         return 0;
 236
 237 nfattr_failure:
 238         return -1;
 239 }
 240
 241 static inline int
 242 ctnetlink_dump_use(struct sk_buff *skb, const struct ip_conntrack *ct)
 243 {
 244         u_int32_t use = htonl(atomic_read(&ct->ct_general.use));
 245
 246         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 247         return 0;
 248
 249 nfattr_failure:
 250         return -1;
 251 }
 252
 253 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 254
 255 static int
 256 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 257                     int event, int nowait,
 258                     const struct ip_conntrack *ct)
 259 {
 260         struct nlmsghdr *nlh;
 261         struct nfgenmsg *nfmsg;
 262         struct nfattr *nest_parms;
 263         unsigned char *b;
 264
 265         b = skb->tail;
 266
 267         event |= NFNL_SUBSYS_CTNETLINK << 8;
 268         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 269         nfmsg  = NLMSG_DATA(nlh);
 270
 271         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 272         nfmsg->nfgen_family = AF_INET;
 273         nfmsg->version      = NFNETLINK_V0;
 274         nfmsg->res_id       = 0;
 275
 276         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 277         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 278                 goto nfattr_failure;
 279         NFA_NEST_END(skb, nest_parms);
 280
 281         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 282         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 283                 goto nfattr_failure;
 284         NFA_NEST_END(skb, nest_parms);
 285
 286         if (ctnetlink_dump_status(skb, ct) < 0 ||
 287             ctnetlink_dump_timeout(skb, ct) < 0 ||
 288             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 289             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 290             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 291             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 292             ctnetlink_dump_mark(skb, ct) < 0 ||
 293             ctnetlink_dump_id(skb, ct) < 0 ||
 294             ctnetlink_dump_use(skb, ct) < 0)
 295                 goto nfattr_failure;
 296
 297         nlh->nlmsg_len = skb->tail - b;
 298         return skb->len;
 299
 300 nlmsg_failure:
 301 nfattr_failure:
 302         skb_trim(skb, b - skb->data);
 303         return -1;
 304 }
 305
 306 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
 307 static int ctnetlink_conntrack_event(struct notifier_block *this,
 308                                      unsigned long events, void *ptr)
 309 {
 310         struct nlmsghdr *nlh;
 311         struct nfgenmsg *nfmsg;
 312         struct nfattr *nest_parms;
 313         struct ip_conntrack *ct = (struct ip_conntrack *)ptr;
 314         struct sk_buff *skb;
 315         unsigned int type;
 316         unsigned char *b;
 317         unsigned int flags = 0, group;
 318
 319         /* ignore our fake conntrack entry */
 320         if (ct == &ip_conntrack_untracked)
 321                 return NOTIFY_DONE;
 322
 323         if (events & IPCT_DESTROY) {
 324                 type = IPCTNL_MSG_CT_DELETE;
 325                 group = NFNLGRP_CONNTRACK_DESTROY;
 326         } else if (events & (IPCT_NEW | IPCT_RELATED)) {
 327                 type = IPCTNL_MSG_CT_NEW;
 328                 flags = NLM_F_CREATE|NLM_F_EXCL;
 329                 /* dump everything */
 330                 events = ~0UL;
 331                 group = NFNLGRP_CONNTRACK_NEW;
 332         } else if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 333                 type = IPCTNL_MSG_CT_NEW;
 334                 group = NFNLGRP_CONNTRACK_UPDATE;
 335         } else
 336                 return NOTIFY_DONE;
 337
 338         if (!nfnetlink_has_listeners(group))
 339                 return NOTIFY_DONE;
 340
 341         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 342         if (!skb)
 343                 return NOTIFY_DONE;
 344
 345         b = skb->tail;
 346
 347         type |= NFNL_SUBSYS_CTNETLINK << 8;
 348         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 349         nfmsg = NLMSG_DATA(nlh);
 350
 351         nlh->nlmsg_flags    = flags;
 352         nfmsg->nfgen_family = AF_INET;
 353         nfmsg->version  = NFNETLINK_V0;
 354         nfmsg->res_id   = 0;
 355
 356         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 357         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 358                 goto nfattr_failure;
 359         NFA_NEST_END(skb, nest_parms);
 360
 361         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 362         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 363                 goto nfattr_failure;
 364         NFA_NEST_END(skb, nest_parms);
 365
 366         /* NAT stuff is now a status flag */
 367         if ((events & IPCT_STATUS || events & IPCT_NATINFO)
 368             && ctnetlink_dump_status(skb, ct) < 0)
 369                 goto nfattr_failure;
 370         if (events & IPCT_REFRESH
 371             && ctnetlink_dump_timeout(skb, ct) < 0)
 372                 goto nfattr_failure;
 373         if (events & IPCT_PROTOINFO
 374             && ctnetlink_dump_protoinfo(skb, ct) < 0)
 375                 goto nfattr_failure;
 376         if (events & IPCT_HELPINFO
 377             && ctnetlink_dump_helpinfo(skb, ct) < 0)
 378                 goto nfattr_failure;
 379
 380         if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 381             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 382                 goto nfattr_failure;
 383
 384         if (events & IPCT_MARK
 385             && ctnetlink_dump_mark(skb, ct) < 0)
 386                 goto nfattr_failure;
 387
 388         nlh->nlmsg_len = skb->tail - b;
 389         nfnetlink_send(skb, 0, group, 0);
 390         return NOTIFY_DONE;
 391
 392 nlmsg_failure:
 393 nfattr_failure:
 394         kfree_skb(skb);
 395         return NOTIFY_DONE;
 396 }
 397 #endif /* CONFIG_IP_NF_CONNTRACK_EVENTS */
 398
 399 static int ctnetlink_done(struct netlink_callback *cb)
 400 {
 401         DEBUGP("entered %s\n", __FUNCTION__);
 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         DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__,
 415                         cb->args[0], *id);
 416
 417         read_lock_bh(&ip_conntrack_lock);
 418         last = (struct ip_conntrack *)cb->args[1];
 419         for (; cb->args[0] < ip_conntrack_htable_size; cb->args[0]++) {
 420 restart:
 421                 list_for_each_prev(i, &ip_conntrack_hash[cb->args[0]]) {
 422                         h = (struct ip_conntrack_tuple_hash *) i;
 423                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 424                                 continue;
 425                         ct = tuplehash_to_ctrack(h);
 426                         if (cb->args[1]) {
 427                                 if (ct != last)
 428                                         continue;
 429                                 cb->args[1] = 0;
 430                         }
 431                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 432                                                 cb->nlh->nlmsg_seq,
 433                                                 IPCTNL_MSG_CT_NEW,
 434                                                 1, ct) < 0) {
 435                                 nf_conntrack_get(&ct->ct_general);
 436                                 cb->args[1] = (unsigned long)ct;
 437                                 goto out;
 438                         }
 439 #ifdef CONFIG_NF_CT_ACCT
 440                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 441                                                 IPCTNL_MSG_CT_GET_CTRZERO)
 442                                 memset(&ct->counters, 0, sizeof(ct->counters));
 443 #endif
 444                 }
 445                 if (cb->args[1]) {
 446                         cb->args[1] = 0;
 447                         goto restart;
 448                 }
 449         }
 450 out:
 451         read_unlock_bh(&ip_conntrack_lock);
 452         if (last)
 453                 ip_conntrack_put(last);
 454
 455         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 456         return skb->len;
 457 }
 458
 459 static const size_t cta_min_ip[CTA_IP_MAX] = {
 460         [CTA_IP_V4_SRC-1]       = sizeof(u_int32_t),
 461         [CTA_IP_V4_DST-1]       = sizeof(u_int32_t),
 462 };
 463
 464 static inline int
 465 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct ip_conntrack_tuple *tuple)
 466 {
 467         struct nfattr *tb[CTA_IP_MAX];
 468
 469         DEBUGP("entered %s\n", __FUNCTION__);
 470
 471         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 472
 473         if (nfattr_bad_size(tb, CTA_IP_MAX, cta_min_ip))
 474                 return -EINVAL;
 475
 476         if (!tb[CTA_IP_V4_SRC-1])
 477                 return -EINVAL;
 478         tuple->src.ip = *(u_int32_t *)NFA_DATA(tb[CTA_IP_V4_SRC-1]);
 479
 480         if (!tb[CTA_IP_V4_DST-1])
 481                 return -EINVAL;
 482         tuple->dst.ip = *(u_int32_t *)NFA_DATA(tb[CTA_IP_V4_DST-1]);
 483
 484         DEBUGP("leaving\n");
 485
 486         return 0;
 487 }
 488
 489 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 490         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 491         [CTA_PROTO_SRC_PORT-1]  = sizeof(u_int16_t),
 492         [CTA_PROTO_DST_PORT-1]  = sizeof(u_int16_t),
 493         [CTA_PROTO_ICMP_TYPE-1] = sizeof(u_int8_t),
 494         [CTA_PROTO_ICMP_CODE-1] = sizeof(u_int8_t),
 495         [CTA_PROTO_ICMP_ID-1]   = sizeof(u_int16_t),
 496 };
 497
 498 static inline int
 499 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 500                             struct ip_conntrack_tuple *tuple)
 501 {
 502         struct nfattr *tb[CTA_PROTO_MAX];
 503         struct ip_conntrack_protocol *proto;
 504         int ret = 0;
 505
 506         DEBUGP("entered %s\n", __FUNCTION__);
 507
 508         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 509
 510         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 511                 return -EINVAL;
 512
 513         if (!tb[CTA_PROTO_NUM-1])
 514                 return -EINVAL;
 515         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 516
 517         proto = ip_conntrack_proto_find_get(tuple->dst.protonum);
 518
 519         if (likely(proto->nfattr_to_tuple))
 520                 ret = proto->nfattr_to_tuple(tb, tuple);
 521
 522         ip_conntrack_proto_put(proto);
 523
 524         return ret;
 525 }
 526
 527 static inline int
 528 ctnetlink_parse_tuple(struct nfattr *cda[], struct ip_conntrack_tuple *tuple,
 529                       enum ctattr_tuple type)
 530 {
 531         struct nfattr *tb[CTA_TUPLE_MAX];
 532         int err;
 533
 534         DEBUGP("entered %s\n", __FUNCTION__);
 535
 536         memset(tuple, 0, sizeof(*tuple));
 537
 538         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 539
 540         if (!tb[CTA_TUPLE_IP-1])
 541                 return -EINVAL;
 542
 543         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 544         if (err < 0)
 545                 return err;
 546
 547         if (!tb[CTA_TUPLE_PROTO-1])
 548                 return -EINVAL;
 549
 550         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 551         if (err < 0)
 552                 return err;
 553
 554         /* orig and expect tuples get DIR_ORIGINAL */
 555         if (type == CTA_TUPLE_REPLY)
 556                 tuple->dst.dir = IP_CT_DIR_REPLY;
 557         else
 558                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 559
 560         DUMP_TUPLE(tuple);
 561
 562         DEBUGP("leaving\n");
 563
 564         return 0;
 565 }
 566
 567 #ifdef CONFIG_IP_NF_NAT_NEEDED
 568 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 569         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 570         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 571 };
 572
 573 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 574                                      const struct ip_conntrack *ct,
 575                                      struct ip_nat_range *range)
 576 {
 577         struct nfattr *tb[CTA_PROTONAT_MAX];
 578         struct ip_nat_protocol *npt;
 579
 580         DEBUGP("entered %s\n", __FUNCTION__);
 581
 582         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 583
 584         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 585                 return -EINVAL;
 586
 587         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 588
 589         if (!npt->nfattr_to_range) {
 590                 ip_nat_proto_put(npt);
 591                 return 0;
 592         }
 593
 594         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 595         if (npt->nfattr_to_range(tb, range) > 0)
 596                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 597
 598         ip_nat_proto_put(npt);
 599
 600         DEBUGP("leaving\n");
 601         return 0;
 602 }
 603
 604 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 605         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 606         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 607 };
 608
 609 static inline int
 610 ctnetlink_parse_nat(struct nfattr *nat,
 611                     const struct ip_conntrack *ct, struct ip_nat_range *range)
 612 {
 613         struct nfattr *tb[CTA_NAT_MAX];
 614         int err;
 615
 616         DEBUGP("entered %s\n", __FUNCTION__);
 617
 618         memset(range, 0, sizeof(*range));
 619
 620         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 621
 622         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 623                 return -EINVAL;
 624
 625         if (tb[CTA_NAT_MINIP-1])
 626                 range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 627
 628         if (!tb[CTA_NAT_MAXIP-1])
 629                 range->max_ip = range->min_ip;
 630         else
 631                 range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 632
 633         if (range->min_ip)
 634                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 635
 636         if (!tb[CTA_NAT_PROTO-1])
 637                 return 0;
 638
 639         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 640         if (err < 0)
 641                 return err;
 642
 643         DEBUGP("leaving\n");
 644         return 0;
 645 }
 646 #endif
 647
 648 static inline int
 649 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 650 {
 651         struct nfattr *tb[CTA_HELP_MAX];
 652
 653         DEBUGP("entered %s\n", __FUNCTION__);
 654
 655         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 656
 657         if (!tb[CTA_HELP_NAME-1])
 658                 return -EINVAL;
 659
 660         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 661
 662         return 0;
 663 }
 664
 665 static const size_t cta_min[CTA_MAX] = {
 666         [CTA_STATUS-1]          = sizeof(u_int32_t),
 667         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 668         [CTA_MARK-1]            = sizeof(u_int32_t),
 669         [CTA_USE-1]             = sizeof(u_int32_t),
 670         [CTA_ID-1]              = sizeof(u_int32_t)
 671 };
 672
 673 static int
 674 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 675                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 676 {
 677         struct ip_conntrack_tuple_hash *h;
 678         struct ip_conntrack_tuple tuple;
 679         struct ip_conntrack *ct;
 680         int err = 0;
 681
 682         DEBUGP("entered %s\n", __FUNCTION__);
 683
 684         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 685                 return -EINVAL;
 686
 687         if (cda[CTA_TUPLE_ORIG-1])
 688                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG);
 689         else if (cda[CTA_TUPLE_REPLY-1])
 690                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY);
 691         else {
 692                 /* Flush the whole table */
 693                 ip_conntrack_flush();
 694                 return 0;
 695         }
 696
 697         if (err < 0)
 698                 return err;
 699
 700         h = ip_conntrack_find_get(&tuple, NULL);
 701         if (!h) {
 702                 DEBUGP("tuple not found in conntrack hash\n");
 703                 return -ENOENT;
 704         }
 705
 706         ct = tuplehash_to_ctrack(h);
 707
 708         if (cda[CTA_ID-1]) {
 709                 u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1]));
 710                 if (ct->id != id) {
 711                         ip_conntrack_put(ct);
 712                         return -ENOENT;
 713                 }
 714         }
 715         if (del_timer(&ct->timeout))
 716                 ct->timeout.function((unsigned long)ct);
 717
 718         ip_conntrack_put(ct);
 719         DEBUGP("leaving\n");
 720
 721         return 0;
 722 }
 723
 724 static int
 725 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 726                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 727 {
 728         struct ip_conntrack_tuple_hash *h;
 729         struct ip_conntrack_tuple tuple;
 730         struct ip_conntrack *ct;
 731         struct sk_buff *skb2 = NULL;
 732         int err = 0;
 733
 734         DEBUGP("entered %s\n", __FUNCTION__);
 735
 736         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 737                 struct nfgenmsg *msg = NLMSG_DATA(nlh);
 738                 u32 rlen;
 739
 740                 if (msg->nfgen_family != AF_INET)
 741                         return -EAFNOSUPPORT;
 742
 743 #ifndef CONFIG_IP_NF_CT_ACCT
 744                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
 745                         return -ENOTSUPP;
 746 #endif
 747                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 748                                                 ctnetlink_dump_table,
 749                                                 ctnetlink_done)) != 0)
 750                         return -EINVAL;
 751
 752                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 753                 if (rlen > skb->len)
 754                         rlen = skb->len;
 755                 skb_pull(skb, rlen);
 756                 return 0;
 757         }
 758
 759         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 760                 return -EINVAL;
 761
 762         if (cda[CTA_TUPLE_ORIG-1])
 763                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG);
 764         else if (cda[CTA_TUPLE_REPLY-1])
 765                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY);
 766         else
 767                 return -EINVAL;
 768
 769         if (err < 0)
 770                 return err;
 771
 772         h = ip_conntrack_find_get(&tuple, NULL);
 773         if (!h) {
 774                 DEBUGP("tuple not found in conntrack hash");
 775                 return -ENOENT;
 776         }
 777         DEBUGP("tuple found\n");
 778         ct = tuplehash_to_ctrack(h);
 779
 780         err = -ENOMEM;
 781         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 782         if (!skb2) {
 783                 ip_conntrack_put(ct);
 784                 return -ENOMEM;
 785         }
 786         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
 787
 788         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 789                                   IPCTNL_MSG_CT_NEW, 1, ct);
 790         ip_conntrack_put(ct);
 791         if (err <= 0)
 792                 goto free;
 793
 794         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 795         if (err < 0)
 796                 goto out;
 797
 798         DEBUGP("leaving\n");
 799         return 0;
 800
 801 free:
 802         kfree_skb(skb2);
 803 out:
 804         return err;
 805 }
 806
 807 static inline int
 808 ctnetlink_change_status(struct ip_conntrack *ct, struct nfattr *cda[])
 809 {
 810         unsigned long d;
 811         unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1]));
 812         d = ct->status ^ status;
 813
 814         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 815                 /* unchangeable */
 816                 return -EINVAL;
 817
 818         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 819                 /* SEEN_REPLY bit can only be set */
 820                 return -EINVAL;
 821
 822
 823         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 824                 /* ASSURED bit can only be set */
 825                 return -EINVAL;
 826
 827         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 828 #ifndef CONFIG_IP_NF_NAT_NEEDED
 829                 return -EINVAL;
 830 #else
 831                 struct ip_nat_range range;
 832
 833                 if (cda[CTA_NAT_DST-1]) {
 834                         if (ctnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 835                                                 &range) < 0)
 836                                 return -EINVAL;
 837                         if (ip_nat_initialized(ct,
 838                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 839                                 return -EEXIST;
 840                         ip_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
 841                 }
 842                 if (cda[CTA_NAT_SRC-1]) {
 843                         if (ctnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 844                                                 &range) < 0)
 845                                 return -EINVAL;
 846                         if (ip_nat_initialized(ct,
 847                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 848                                 return -EEXIST;
 849                         ip_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
 850                 }
 851 #endif
 852         }
 853
 854         /* Be careful here, modifying NAT bits can screw up things,
 855          * so don't let users modify them directly if they don't pass
 856          * ip_nat_range. */
 857         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 858         return 0;
 859 }
 860
 861
 862 static inline int
 863 ctnetlink_change_helper(struct ip_conntrack *ct, struct nfattr *cda[])
 864 {
 865         struct ip_conntrack_helper *helper;
 866         char *helpname;
 867         int err;
 868
 869         DEBUGP("entered %s\n", __FUNCTION__);
 870
 871         /* don't change helper of sibling connections */
 872         if (ct->master)
 873                 return -EINVAL;
 874
 875         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 876         if (err < 0)
 877                 return err;
 878
 879         helper = __ip_conntrack_helper_find_byname(helpname);
 880         if (!helper) {
 881                 if (!strcmp(helpname, ""))
 882                         helper = NULL;
 883                 else
 884                         return -EINVAL;
 885         }
 886
 887         if (ct->helper) {
 888                 if (!helper) {
 889                         /* we had a helper before ... */
 890                         ip_ct_remove_expectations(ct);
 891                         ct->helper = NULL;
 892                 } else {
 893                         /* need to zero data of old helper */
 894                         memset(&ct->help, 0, sizeof(ct->help));
 895                 }
 896         }
 897
 898         ct->helper = helper;
 899
 900         return 0;
 901 }
 902
 903 static inline int
 904 ctnetlink_change_timeout(struct ip_conntrack *ct, struct nfattr *cda[])
 905 {
 906         u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 907
 908         if (!del_timer(&ct->timeout))
 909                 return -ETIME;
 910
 911         ct->timeout.expires = jiffies + timeout * HZ;
 912         add_timer(&ct->timeout);
 913
 914         return 0;
 915 }
 916
 917 static inline int
 918 ctnetlink_change_protoinfo(struct ip_conntrack *ct, struct nfattr *cda[])
 919 {
 920         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 921         struct ip_conntrack_protocol *proto;
 922         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 923         int err = 0;
 924
 925         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 926
 927         proto = ip_conntrack_proto_find_get(npt);
 928
 929         if (proto->from_nfattr)
 930                 err = proto->from_nfattr(tb, ct);
 931         ip_conntrack_proto_put(proto);
 932
 933         return err;
 934 }
 935
 936 static int
 937 ctnetlink_change_conntrack(struct ip_conntrack *ct, struct nfattr *cda[])
 938 {
 939         int err;
 940
 941         DEBUGP("entered %s\n", __FUNCTION__);
 942
 943         if (cda[CTA_HELP-1]) {
 944                 err = ctnetlink_change_helper(ct, cda);
 945                 if (err < 0)
 946                         return err;
 947         }
 948
 949         if (cda[CTA_TIMEOUT-1]) {
 950                 err = ctnetlink_change_timeout(ct, cda);
 951                 if (err < 0)
 952                         return err;
 953         }
 954
 955         if (cda[CTA_STATUS-1]) {
 956                 err = ctnetlink_change_status(ct, cda);
 957                 if (err < 0)
 958                         return err;
 959         }
 960
 961         if (cda[CTA_PROTOINFO-1]) {
 962                 err = ctnetlink_change_protoinfo(ct, cda);
 963                 if (err < 0)
 964                         return err;
 965         }
 966
 967 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
 968         if (cda[CTA_MARK-1])
 969                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
 970 #endif
 971
 972         DEBUGP("all done\n");
 973         return 0;
 974 }
 975
 976 static int
 977 ctnetlink_create_conntrack(struct nfattr *cda[],
 978                            struct ip_conntrack_tuple *otuple,
 979                            struct ip_conntrack_tuple *rtuple)
 980 {
 981         struct ip_conntrack *ct;
 982         int err = -EINVAL;
 983
 984         DEBUGP("entered %s\n", __FUNCTION__);
 985
 986         ct = ip_conntrack_alloc(otuple, rtuple);
 987         if (ct == NULL || IS_ERR(ct))
 988                 return -ENOMEM;
 989
 990         if (!cda[CTA_TIMEOUT-1])
 991                 goto err;
 992         ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 993
 994         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
 995         ct->status |= IPS_CONFIRMED;
 996
 997         err = ctnetlink_change_status(ct, cda);
 998         if (err < 0)
 999                 goto err;
1000
1001         if (cda[CTA_PROTOINFO-1]) {
1002                 err = ctnetlink_change_protoinfo(ct, cda);
1003                 if (err < 0)
1004                         return err;
1005         }
1006
1007 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
1008         if (cda[CTA_MARK-1])
1009                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1010 #endif
1011
1012         ct->helper = ip_conntrack_helper_find_get(rtuple);
1013
1014         add_timer(&ct->timeout);
1015         ip_conntrack_hash_insert(ct);
1016
1017         if (ct->helper)
1018                 ip_conntrack_helper_put(ct->helper);
1019
1020         DEBUGP("conntrack with id %u inserted\n", ct->id);
1021         return 0;
1022
1023 err:
1024         ip_conntrack_free(ct);
1025         return err;
1026 }
1027
1028 static int
1029 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1030                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1031 {
1032         struct ip_conntrack_tuple otuple, rtuple;
1033         struct ip_conntrack_tuple_hash *h = NULL;
1034         int err = 0;
1035
1036         DEBUGP("entered %s\n", __FUNCTION__);
1037
1038         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1039                 return -EINVAL;
1040
1041         if (cda[CTA_TUPLE_ORIG-1]) {
1042                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG);
1043                 if (err < 0)
1044                         return err;
1045         }
1046
1047         if (cda[CTA_TUPLE_REPLY-1]) {
1048                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY);
1049                 if (err < 0)
1050                         return err;
1051         }
1052
1053         write_lock_bh(&ip_conntrack_lock);
1054         if (cda[CTA_TUPLE_ORIG-1])
1055                 h = __ip_conntrack_find(&otuple, NULL);
1056         else if (cda[CTA_TUPLE_REPLY-1])
1057                 h = __ip_conntrack_find(&rtuple, NULL);
1058
1059         if (h == NULL) {
1060                 write_unlock_bh(&ip_conntrack_lock);
1061                 DEBUGP("no such conntrack, create new\n");
1062                 err = -ENOENT;
1063                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1064                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1065                 return err;
1066         }
1067         /* implicit 'else' */
1068
1069         /* we only allow nat config for new conntracks */
1070         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1071                 err = -EINVAL;
1072                 goto out_unlock;
1073         }
1074
1075         /* We manipulate the conntrack inside the global conntrack table lock,
1076          * so there's no need to increase the refcount */
1077         DEBUGP("conntrack found\n");
1078         err = -EEXIST;
1079         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1080                 err = ctnetlink_change_conntrack(tuplehash_to_ctrack(h), cda);
1081
1082 out_unlock:
1083         write_unlock_bh(&ip_conntrack_lock);
1084         return err;
1085 }
1086
1087 /***********************************************************************
1088  * EXPECT
1089  ***********************************************************************/
1090
1091 static inline int
1092 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1093                          const struct ip_conntrack_tuple *tuple,
1094                          enum ctattr_expect type)
1095 {
1096         struct nfattr *nest_parms = NFA_NEST(skb, type);
1097
1098         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1099                 goto nfattr_failure;
1100
1101         NFA_NEST_END(skb, nest_parms);
1102
1103         return 0;
1104
1105 nfattr_failure:
1106         return -1;
1107 }
1108
1109 static inline int
1110 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1111                         const struct ip_conntrack_tuple *tuple,
1112                         const struct ip_conntrack_tuple *mask)
1113 {
1114         int ret;
1115         struct ip_conntrack_protocol *proto;
1116         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1117
1118         ret = ctnetlink_dump_tuples_ip(skb, mask);
1119         if (unlikely(ret < 0))
1120                 goto nfattr_failure;
1121
1122         proto = ip_conntrack_proto_find_get(tuple->dst.protonum);
1123         ret = ctnetlink_dump_tuples_proto(skb, mask, proto);
1124         ip_conntrack_proto_put(proto);
1125         if (unlikely(ret < 0))
1126                 goto nfattr_failure;
1127
1128         NFA_NEST_END(skb, nest_parms);
1129
1130         return 0;
1131
1132 nfattr_failure:
1133         return -1;
1134 }
1135
1136 static inline int
1137 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1138                           const struct ip_conntrack_expect *exp)
1139 {
1140         struct ip_conntrack *master = exp->master;
1141         u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1142         u_int32_t id = htonl(exp->id);
1143
1144         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1145                 goto nfattr_failure;
1146         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1147                 goto nfattr_failure;
1148         if (ctnetlink_exp_dump_tuple(skb,
1149                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1150                                  CTA_EXPECT_MASTER) < 0)
1151                 goto nfattr_failure;
1152
1153         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1154         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1155
1156         return 0;
1157
1158 nfattr_failure:
1159         return -1;
1160 }
1161
1162 static int
1163 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1164                     int event,
1165                     int nowait,
1166                     const struct ip_conntrack_expect *exp)
1167 {
1168         struct nlmsghdr *nlh;
1169         struct nfgenmsg *nfmsg;
1170         unsigned char *b;
1171
1172         b = skb->tail;
1173
1174         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1175         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1176         nfmsg  = NLMSG_DATA(nlh);
1177
1178         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1179         nfmsg->nfgen_family = AF_INET;
1180         nfmsg->version      = NFNETLINK_V0;
1181         nfmsg->res_id       = 0;
1182
1183         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1184                 goto nfattr_failure;
1185
1186         nlh->nlmsg_len = skb->tail - b;
1187         return skb->len;
1188
1189 nlmsg_failure:
1190 nfattr_failure:
1191         skb_trim(skb, b - skb->data);
1192         return -1;
1193 }
1194
1195 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1196 static int ctnetlink_expect_event(struct notifier_block *this,
1197                                   unsigned long events, void *ptr)
1198 {
1199         struct nlmsghdr *nlh;
1200         struct nfgenmsg *nfmsg;
1201         struct ip_conntrack_expect *exp = (struct ip_conntrack_expect *)ptr;
1202         struct sk_buff *skb;
1203         unsigned int type;
1204         unsigned char *b;
1205         int flags = 0;
1206
1207         if (events & IPEXP_NEW) {
1208                 type = IPCTNL_MSG_EXP_NEW;
1209                 flags = NLM_F_CREATE|NLM_F_EXCL;
1210         } else
1211                 return NOTIFY_DONE;
1212
1213         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1214                 return NOTIFY_DONE;
1215
1216         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1217         if (!skb)
1218                 return NOTIFY_DONE;
1219
1220         b = skb->tail;
1221
1222         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1223         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1224         nfmsg = NLMSG_DATA(nlh);
1225
1226         nlh->nlmsg_flags    = flags;
1227         nfmsg->nfgen_family = AF_INET;
1228         nfmsg->version      = NFNETLINK_V0;
1229         nfmsg->res_id       = 0;
1230
1231         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1232                 goto nfattr_failure;
1233
1234         nlh->nlmsg_len = skb->tail - b;
1235         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1236         return NOTIFY_DONE;
1237
1238 nlmsg_failure:
1239 nfattr_failure:
1240         kfree_skb(skb);
1241         return NOTIFY_DONE;
1242 }
1243 #endif
1244
1245 static int
1246 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1247 {
1248         struct ip_conntrack_expect *exp = NULL;
1249         struct list_head *i;
1250         u_int32_t *id = (u_int32_t *) &cb->args[0];
1251
1252         DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id);
1253
1254         read_lock_bh(&ip_conntrack_lock);
1255         list_for_each_prev(i, &ip_conntrack_expect_list) {
1256                 exp = (struct ip_conntrack_expect *) i;
1257                 if (exp->id <= *id)
1258                         continue;
1259                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1260                                             cb->nlh->nlmsg_seq,
1261                                             IPCTNL_MSG_EXP_NEW,
1262                                             1, exp) < 0)
1263                         goto out;
1264                 *id = exp->id;
1265         }
1266 out:
1267         read_unlock_bh(&ip_conntrack_lock);
1268
1269         DEBUGP("leaving, last id=%llu\n", *id);
1270
1271         return skb->len;
1272 }
1273
1274 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1275         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1276         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1277 };
1278
1279 static int
1280 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1281                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1282 {
1283         struct ip_conntrack_tuple tuple;
1284         struct ip_conntrack_expect *exp;
1285         struct sk_buff *skb2;
1286         int err = 0;
1287
1288         DEBUGP("entered %s\n", __FUNCTION__);
1289
1290         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1291                 return -EINVAL;
1292
1293         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1294                 struct nfgenmsg *msg = NLMSG_DATA(nlh);
1295                 u32 rlen;
1296
1297                 if (msg->nfgen_family != AF_INET)
1298                         return -EAFNOSUPPORT;
1299
1300                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1301                                                 ctnetlink_exp_dump_table,
1302                                                 ctnetlink_done)) != 0)
1303                         return -EINVAL;
1304                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1305                 if (rlen > skb->len)
1306                         rlen = skb->len;
1307                 skb_pull(skb, rlen);
1308                 return 0;
1309         }
1310
1311         if (cda[CTA_EXPECT_MASTER-1])
1312                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER);
1313         else
1314                 return -EINVAL;
1315
1316         if (err < 0)
1317                 return err;
1318
1319         exp = ip_conntrack_expect_find(&tuple);
1320         if (!exp)
1321                 return -ENOENT;
1322
1323         if (cda[CTA_EXPECT_ID-1]) {
1324                 u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1325                 if (exp->id != ntohl(id)) {
1326                         ip_conntrack_expect_put(exp);
1327                         return -ENOENT;
1328                 }
1329         }
1330
1331         err = -ENOMEM;
1332         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1333         if (!skb2)
1334                 goto out;
1335         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
1336
1337         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1338                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1339                                       1, exp);
1340         if (err <= 0)
1341                 goto free;
1342
1343         ip_conntrack_expect_put(exp);
1344
1345         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1346
1347 free:
1348         kfree_skb(skb2);
1349 out:
1350         ip_conntrack_expect_put(exp);
1351         return err;
1352 }
1353
1354 static int
1355 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1356                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1357 {
1358         struct ip_conntrack_expect *exp, *tmp;
1359         struct ip_conntrack_tuple tuple;
1360         struct ip_conntrack_helper *h;
1361         int err;
1362
1363         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1364                 return -EINVAL;
1365
1366         if (cda[CTA_EXPECT_TUPLE-1]) {
1367                 /* delete a single expect by tuple */
1368                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE);
1369                 if (err < 0)
1370                         return err;
1371
1372                 /* bump usage count to 2 */
1373                 exp = ip_conntrack_expect_find(&tuple);
1374                 if (!exp)
1375                         return -ENOENT;
1376
1377                 if (cda[CTA_EXPECT_ID-1]) {
1378                         u_int32_t id =
1379                                 *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1380                         if (exp->id != ntohl(id)) {
1381                                 ip_conntrack_expect_put(exp);
1382                                 return -ENOENT;
1383                         }
1384                 }
1385
1386                 /* after list removal, usage count == 1 */
1387                 ip_conntrack_unexpect_related(exp);
1388                 /* have to put what we 'get' above.
1389                  * after this line usage count == 0 */
1390                 ip_conntrack_expect_put(exp);
1391         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1392                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1393
1394                 /* delete all expectations for this helper */
1395                 write_lock_bh(&ip_conntrack_lock);
1396                 h = __ip_conntrack_helper_find_byname(name);
1397                 if (!h) {
1398                         write_unlock_bh(&ip_conntrack_lock);
1399                         return -EINVAL;
1400                 }
1401                 list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list,
1402                                          list) {
1403                         if (exp->master->helper == h
1404                             && del_timer(&exp->timeout)) {
1405                                 ip_ct_unlink_expect(exp);
1406                                 ip_conntrack_expect_put(exp);
1407                         }
1408                 }
1409                 write_unlock_bh(&ip_conntrack_lock);
1410         } else {
1411                 /* This basically means we have to flush everything*/
1412                 write_lock_bh(&ip_conntrack_lock);
1413                 list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list,
1414                                          list) {
1415                         if (del_timer(&exp->timeout)) {
1416                                 ip_ct_unlink_expect(exp);
1417                                 ip_conntrack_expect_put(exp);
1418                         }
1419                 }
1420                 write_unlock_bh(&ip_conntrack_lock);
1421         }
1422
1423         return 0;
1424 }
1425 static int
1426 ctnetlink_change_expect(struct ip_conntrack_expect *x, struct nfattr *cda[])
1427 {
1428         return -EOPNOTSUPP;
1429 }
1430
1431 static int
1432 ctnetlink_create_expect(struct nfattr *cda[])
1433 {
1434         struct ip_conntrack_tuple tuple, mask, master_tuple;
1435         struct ip_conntrack_tuple_hash *h = NULL;
1436         struct ip_conntrack_expect *exp;
1437         struct ip_conntrack *ct;
1438         int err = 0;
1439
1440         DEBUGP("entered %s\n", __FUNCTION__);
1441
1442         /* caller guarantees that those three CTA_EXPECT_* exist */
1443         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE);
1444         if (err < 0)
1445                 return err;
1446         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK);
1447         if (err < 0)
1448                 return err;
1449         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER);
1450         if (err < 0)
1451                 return err;
1452
1453         /* Look for master conntrack of this expectation */
1454         h = ip_conntrack_find_get(&master_tuple, NULL);
1455         if (!h)
1456                 return -ENOENT;
1457         ct = tuplehash_to_ctrack(h);
1458
1459         if (!ct->helper) {
1460                 /* such conntrack hasn't got any helper, abort */
1461                 err = -EINVAL;
1462                 goto out;
1463         }
1464
1465         exp = ip_conntrack_expect_alloc(ct);
1466         if (!exp) {
1467                 err = -ENOMEM;
1468                 goto out;
1469         }
1470
1471         exp->expectfn = NULL;
1472         exp->flags = 0;
1473         exp->master = ct;
1474         memcpy(&exp->tuple, &tuple, sizeof(struct ip_conntrack_tuple));
1475         memcpy(&exp->mask, &mask, sizeof(struct ip_conntrack_tuple));
1476
1477         err = ip_conntrack_expect_related(exp);
1478         ip_conntrack_expect_put(exp);
1479
1480 out:
1481         ip_conntrack_put(tuplehash_to_ctrack(h));
1482         return err;
1483 }
1484
1485 static int
1486 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1487                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1488 {
1489         struct ip_conntrack_tuple tuple;
1490         struct ip_conntrack_expect *exp;
1491         int err = 0;
1492
1493         DEBUGP("entered %s\n", __FUNCTION__);
1494
1495         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1496                 return -EINVAL;
1497
1498         if (!cda[CTA_EXPECT_TUPLE-1]
1499             || !cda[CTA_EXPECT_MASK-1]
1500             || !cda[CTA_EXPECT_MASTER-1])
1501                 return -EINVAL;
1502
1503         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE);
1504         if (err < 0)
1505                 return err;
1506
1507         write_lock_bh(&ip_conntrack_lock);
1508         exp = __ip_conntrack_expect_find(&tuple);
1509
1510         if (!exp) {
1511                 write_unlock_bh(&ip_conntrack_lock);
1512                 err = -ENOENT;
1513                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1514                         err = ctnetlink_create_expect(cda);
1515                 return err;
1516         }
1517
1518         err = -EEXIST;
1519         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1520                 err = ctnetlink_change_expect(exp, cda);
1521         write_unlock_bh(&ip_conntrack_lock);
1522
1523         DEBUGP("leaving\n");
1524
1525         return err;
1526 }
1527
1528 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1529 static struct notifier_block ctnl_notifier = {
1530         .notifier_call  = ctnetlink_conntrack_event,
1531 };
1532
1533 static struct notifier_block ctnl_notifier_exp = {
1534         .notifier_call  = ctnetlink_expect_event,
1535 };
1536 #endif
1537
1538 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1539         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1540                                             .attr_count = CTA_MAX, },
1541         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1542                                             .attr_count = CTA_MAX, },
1543         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1544                                             .attr_count = CTA_MAX, },
1545         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1546                                             .attr_count = CTA_MAX, },
1547 };
1548
1549 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1550         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1551                                             .attr_count = CTA_EXPECT_MAX, },
1552         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1553                                             .attr_count = CTA_EXPECT_MAX, },
1554         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1555                                             .attr_count = CTA_EXPECT_MAX, },
1556 };
1557
1558 static struct nfnetlink_subsystem ctnl_subsys = {
1559         .name                           = "conntrack",
1560         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1561         .cb_count                       = IPCTNL_MSG_MAX,
1562         .cb                             = ctnl_cb,
1563 };
1564
1565 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1566         .name                           = "conntrack_expect",
1567         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1568         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1569         .cb                             = ctnl_exp_cb,
1570 };
1571
1572 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1573 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1574
1575 static int __init ctnetlink_init(void)
1576 {
1577         int ret;
1578
1579         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1580         ret = nfnetlink_subsys_register(&ctnl_subsys);
1581         if (ret < 0) {
1582                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1583                 goto err_out;
1584         }
1585
1586         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1587         if (ret < 0) {
1588                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1589                 goto err_unreg_subsys;
1590         }
1591
1592 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1593         ret = ip_conntrack_register_notifier(&ctnl_notifier);
1594         if (ret < 0) {
1595                 printk("ctnetlink_init: cannot register notifier.\n");
1596                 goto err_unreg_exp_subsys;
1597         }
1598
1599         ret = ip_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1600         if (ret < 0) {
1601                 printk("ctnetlink_init: cannot expect register notifier.\n");
1602                 goto err_unreg_notifier;
1603         }
1604 #endif
1605
1606         return 0;
1607
1608 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1609 err_unreg_notifier:
1610         ip_conntrack_unregister_notifier(&ctnl_notifier);
1611 err_unreg_exp_subsys:
1612         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1613 #endif
1614 err_unreg_subsys:
1615         nfnetlink_subsys_unregister(&ctnl_subsys);
1616 err_out:
1617         return ret;
1618 }
1619
1620 static void __exit ctnetlink_exit(void)
1621 {
1622         printk("ctnetlink: unregistering from nfnetlink.\n");
1623
1624 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
1625         ip_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1626         ip_conntrack_unregister_notifier(&ctnl_notifier);
1627 #endif
1628
1629         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1630         nfnetlink_subsys_unregister(&ctnl_subsys);
1631         return;
1632 }
1633
1634 module_init(ctnetlink_init);
1635 module_exit(ctnetlink_exit);