net/netfilter/nf_conntrack_netlink.c

   1 /* Connection tracking via netlink socket. Allows for user space
   2  * protocol helpers and general trouble making from userspace.
   3  *
   4  * (C) 2001 by Jay Schulist <jschlst@samba.org>
   5  * (C) 2002-2005 by Harald Welte <laforge@gnumonks.org>
   6  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
   7  * (C) 2005 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  * Derived from ip_conntrack_netlink.c: Port by Pablo Neira Ayuso (05/11/14)
  21  */
  22
  23 #include <linux/init.h>
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/types.h>
  27 #include <linux/timer.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/errno.h>
  30 #include <linux/netlink.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/notifier.h>
  33
  34 #include <linux/netfilter.h>
  35 #include <net/netfilter/nf_conntrack.h>
  36 #include <net/netfilter/nf_conntrack_core.h>
  37 #include <net/netfilter/nf_conntrack_helper.h>
  38 #include <net/netfilter/nf_conntrack_l3proto.h>
  39 #include <net/netfilter/nf_conntrack_protocol.h>
  40 #include <linux/netfilter_ipv4/ip_nat_protocol.h>
  41
  42 #include <linux/netfilter/nfnetlink.h>
  43 #include <linux/netfilter/nfnetlink_conntrack.h>
  44
  45 MODULE_LICENSE("GPL");
  46
  47 static char __initdata version[] = "0.92";
  48
  49 #if 0
  50 #define DEBUGP printk
  51 #else
  52 #define DEBUGP(format, args...)
  53 #endif
  54
  55
  56 static inline int
  57 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  58                             const struct nf_conntrack_tuple *tuple)
  59 {
  60         struct nf_conntrack_protocol *proto;
  61         int ret = 0;
  62
  63         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  64
  65         /* If no protocol helper is found, this function will return the
  66          * generic protocol helper, so proto won't *ever* be NULL */
  67         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
  68         if (likely(proto->tuple_to_nfattr))
  69                 ret = proto->tuple_to_nfattr(skb, tuple);
  70
  71         nf_ct_proto_put(proto);
  72
  73         return ret;
  74
  75 nfattr_failure:
  76         return -1;
  77 }
  78
  79 static inline int
  80 ctnetlink_dump_tuples(struct sk_buff *skb,
  81                       const struct nf_conntrack_tuple *tuple)
  82 {
  83         struct nfattr *nest_parms;
  84         struct nf_conntrack_l3proto *l3proto;
  85         int ret = 0;
  86
  87         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
  88
  89         nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  90         if (likely(l3proto->tuple_to_nfattr))
  91                 ret = l3proto->tuple_to_nfattr(skb, tuple);
  92         NFA_NEST_END(skb, nest_parms);
  93
  94         nf_ct_l3proto_put(l3proto);
  95
  96         if (unlikely(ret < 0))
  97                 return ret;
  98
  99         nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
 100         ret = ctnetlink_dump_tuples_proto(skb, tuple);
 101         NFA_NEST_END(skb, nest_parms);
 102
 103         return ret;
 104
 105 nfattr_failure:
 106         return -1;
 107 }
 108
 109 static inline int
 110 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 111 {
 112         u_int32_t status = htonl((u_int32_t) ct->status);
 113         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 114         return 0;
 115
 116 nfattr_failure:
 117         return -1;
 118 }
 119
 120 static inline int
 121 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 122 {
 123         long timeout_l = ct->timeout.expires - jiffies;
 124         u_int32_t timeout;
 125
 126         if (timeout_l < 0)
 127                 timeout = 0;
 128         else
 129                 timeout = htonl(timeout_l / HZ);
 130
 131         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 132         return 0;
 133
 134 nfattr_failure:
 135         return -1;
 136 }
 137
 138 static inline int
 139 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 140 {
 141         struct nf_conntrack_protocol *proto = nf_ct_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 142         struct nfattr *nest_proto;
 143         int ret;
 144
 145         if (!proto->to_nfattr) {
 146                 nf_ct_proto_put(proto);
 147                 return 0;
 148         }
 149
 150         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 151
 152         ret = proto->to_nfattr(skb, nest_proto, ct);
 153
 154         nf_ct_proto_put(proto);
 155
 156         NFA_NEST_END(skb, nest_proto);
 157
 158         return ret;
 159
 160 nfattr_failure:
 161         return -1;
 162 }
 163
 164 static inline int
 165 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 166 {
 167         struct nfattr *nest_helper;
 168
 169         if (!ct->helper)
 170                 return 0;
 171
 172         nest_helper = NFA_NEST(skb, CTA_HELP);
 173         NFA_PUT(skb, CTA_HELP_NAME, strlen(ct->helper->name), ct->helper->name);
 174
 175         if (ct->helper->to_nfattr)
 176                 ct->helper->to_nfattr(skb, ct);
 177
 178         NFA_NEST_END(skb, nest_helper);
 179
 180         return 0;
 181
 182 nfattr_failure:
 183         return -1;
 184 }
 185
 186 #ifdef CONFIG_NF_CT_ACCT
 187 static inline int
 188 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 189                         enum ip_conntrack_dir dir)
 190 {
 191         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 192         struct nfattr *nest_count = NFA_NEST(skb, type);
 193         u_int32_t tmp;
 194
 195         tmp = htonl(ct->counters[dir].packets);
 196         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 197
 198         tmp = htonl(ct->counters[dir].bytes);
 199         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 200
 201         NFA_NEST_END(skb, nest_count);
 202
 203         return 0;
 204
 205 nfattr_failure:
 206         return -1;
 207 }
 208 #else
 209 #define ctnetlink_dump_counters(a, b, c) (0)
 210 #endif
 211
 212 #ifdef CONFIG_NF_CONNTRACK_MARK
 213 static inline int
 214 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 215 {
 216         u_int32_t mark = htonl(ct->mark);
 217
 218         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 219         return 0;
 220
 221 nfattr_failure:
 222         return -1;
 223 }
 224 #else
 225 #define ctnetlink_dump_mark(a, b) (0)
 226 #endif
 227
 228 static inline int
 229 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 230 {
 231         u_int32_t id = htonl(ct->id);
 232         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 233         return 0;
 234
 235 nfattr_failure:
 236         return -1;
 237 }
 238
 239 static inline int
 240 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 241 {
 242         u_int32_t use = htonl(atomic_read(&ct->ct_general.use));
 243
 244         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 245         return 0;
 246
 247 nfattr_failure:
 248         return -1;
 249 }
 250
 251 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 252
 253 static int
 254 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 255                     int event, int nowait,
 256                     const struct nf_conn *ct)
 257 {
 258         struct nlmsghdr *nlh;
 259         struct nfgenmsg *nfmsg;
 260         struct nfattr *nest_parms;
 261         unsigned char *b;
 262
 263         b = skb->tail;
 264
 265         event |= NFNL_SUBSYS_CTNETLINK << 8;
 266         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 267         nfmsg  = NLMSG_DATA(nlh);
 268
 269         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 270         nfmsg->nfgen_family =
 271                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 272         nfmsg->version      = NFNETLINK_V0;
 273         nfmsg->res_id       = 0;
 274
 275         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 276         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 277                 goto nfattr_failure;
 278         NFA_NEST_END(skb, nest_parms);
 279
 280         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 281         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 282                 goto nfattr_failure;
 283         NFA_NEST_END(skb, nest_parms);
 284
 285         if (ctnetlink_dump_status(skb, ct) < 0 ||
 286             ctnetlink_dump_timeout(skb, ct) < 0 ||
 287             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 288             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 289             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 290             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 291             ctnetlink_dump_mark(skb, ct) < 0 ||
 292             ctnetlink_dump_id(skb, ct) < 0 ||
 293             ctnetlink_dump_use(skb, ct) < 0)
 294                 goto nfattr_failure;
 295
 296         nlh->nlmsg_len = skb->tail - b;
 297         return skb->len;
 298
 299 nlmsg_failure:
 300 nfattr_failure:
 301         skb_trim(skb, b - skb->data);
 302         return -1;
 303 }
 304
 305 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 306 static int ctnetlink_conntrack_event(struct notifier_block *this,
 307                                      unsigned long events, void *ptr)
 308 {
 309         struct nlmsghdr *nlh;
 310         struct nfgenmsg *nfmsg;
 311         struct nfattr *nest_parms;
 312         struct nf_conn *ct = (struct nf_conn *)ptr;
 313         struct sk_buff *skb;
 314         unsigned int type;
 315         unsigned char *b;
 316         unsigned int flags = 0, group;
 317
 318         /* ignore our fake conntrack entry */
 319         if (ct == &nf_conntrack_untracked)
 320                 return NOTIFY_DONE;
 321
 322         if (events & IPCT_DESTROY) {
 323                 type = IPCTNL_MSG_CT_DELETE;
 324                 group = NFNLGRP_CONNTRACK_DESTROY;
 325         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 326                 type = IPCTNL_MSG_CT_NEW;
 327                 flags = NLM_F_CREATE|NLM_F_EXCL;
 328                 /* dump everything */
 329                 events = ~0UL;
 330                 group = NFNLGRP_CONNTRACK_NEW;
 331         } else  if (events & (IPCT_STATUS |
 332                       IPCT_PROTOINFO |
 333                       IPCT_HELPER |
 334                       IPCT_HELPINFO |
 335                       IPCT_NATINFO)) {
 336                 type = IPCTNL_MSG_CT_NEW;
 337                 group = NFNLGRP_CONNTRACK_UPDATE;
 338         } else
 339                 return NOTIFY_DONE;
 340
 341   /* FIXME: Check if there are any listeners before, don't hurt performance */
 342
 343         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 344         if (!skb)
 345                 return NOTIFY_DONE;
 346
 347         b = skb->tail;
 348
 349         type |= NFNL_SUBSYS_CTNETLINK << 8;
 350         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 351         nfmsg = NLMSG_DATA(nlh);
 352
 353         nlh->nlmsg_flags    = flags;
 354         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 355         nfmsg->version  = NFNETLINK_V0;
 356         nfmsg->res_id   = 0;
 357
 358         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 359         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 360                 goto nfattr_failure;
 361         NFA_NEST_END(skb, nest_parms);
 362
 363         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 364         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 365                 goto nfattr_failure;
 366         NFA_NEST_END(skb, nest_parms);
 367
 368         /* NAT stuff is now a status flag */
 369         if ((events & IPCT_STATUS || events & IPCT_NATINFO)
 370             && ctnetlink_dump_status(skb, ct) < 0)
 371                 goto nfattr_failure;
 372         if (events & IPCT_REFRESH
 373             && ctnetlink_dump_timeout(skb, ct) < 0)
 374                 goto nfattr_failure;
 375         if (events & IPCT_PROTOINFO
 376             && ctnetlink_dump_protoinfo(skb, ct) < 0)
 377                 goto nfattr_failure;
 378         if (events & IPCT_HELPINFO
 379             && ctnetlink_dump_helpinfo(skb, ct) < 0)
 380                 goto nfattr_failure;
 381
 382         if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 383             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 384                 goto nfattr_failure;
 385
 386         nlh->nlmsg_len = skb->tail - b;
 387         nfnetlink_send(skb, 0, group, 0);
 388         return NOTIFY_DONE;
 389
 390 nlmsg_failure:
 391 nfattr_failure:
 392         kfree_skb(skb);
 393         return NOTIFY_DONE;
 394 }
 395 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 396
 397 static int ctnetlink_done(struct netlink_callback *cb)
 398 {
 399         DEBUGP("entered %s\n", __FUNCTION__);
 400         return 0;
 401 }
 402
 403 static int
 404 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 405 {
 406         struct nf_conn *ct = NULL;
 407         struct nf_conntrack_tuple_hash *h;
 408         struct list_head *i;
 409         u_int32_t *id = (u_int32_t *) &cb->args[1];
 410
 411         DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__,
 412                         cb->args[0], *id);
 413
 414         read_lock_bh(&nf_conntrack_lock);
 415         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 416                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 417                         h = (struct nf_conntrack_tuple_hash *) i;
 418                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 419                                 continue;
 420                         ct = nf_ct_tuplehash_to_ctrack(h);
 421                         if (ct->id <= *id)
 422                                 continue;
 423                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 424                                                 cb->nlh->nlmsg_seq,
 425                                                 IPCTNL_MSG_CT_NEW,
 426                                                 1, ct) < 0)
 427                                 goto out;
 428                         *id = ct->id;
 429                 }
 430         }
 431 out:
 432         read_unlock_bh(&nf_conntrack_lock);
 433
 434         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 435
 436         return skb->len;
 437 }
 438
 439 #ifdef CONFIG_NF_CT_ACCT
 440 static int
 441 ctnetlink_dump_table_w(struct sk_buff *skb, struct netlink_callback *cb)
 442 {
 443         struct nf_conn *ct = NULL;
 444         struct nf_conntrack_tuple_hash *h;
 445         struct list_head *i;
 446         u_int32_t *id = (u_int32_t *) &cb->args[1];
 447
 448         DEBUGP("entered %s, last bucket=%u id=%u\n", __FUNCTION__,
 449                         cb->args[0], *id);
 450
 451         write_lock_bh(&nf_conntrack_lock);
 452         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 453                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 454                         h = (struct nf_conntrack_tuple_hash *) i;
 455                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 456                                 continue;
 457                         ct = nf_ct_tuplehash_to_ctrack(h);
 458                         if (ct->id <= *id)
 459                                 continue;
 460                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 461                                                 cb->nlh->nlmsg_seq,
 462                                                 IPCTNL_MSG_CT_NEW,
 463                                                 1, ct) < 0)
 464                                 goto out;
 465                         *id = ct->id;
 466
 467                         memset(&ct->counters, 0, sizeof(ct->counters));
 468                 }
 469         }
 470 out:
 471         write_unlock_bh(&nf_conntrack_lock);
 472
 473         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 474
 475         return skb->len;
 476 }
 477 #endif
 478
 479 static inline int
 480 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 481 {
 482         struct nfattr *tb[CTA_IP_MAX];
 483         struct nf_conntrack_l3proto *l3proto;
 484         int ret = 0;
 485
 486         DEBUGP("entered %s\n", __FUNCTION__);
 487
 488         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 489
 490         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 491
 492         if (likely(l3proto->nfattr_to_tuple))
 493                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 494
 495         nf_ct_l3proto_put(l3proto);
 496
 497         DEBUGP("leaving\n");
 498
 499         return ret;
 500 }
 501
 502 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 503         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 504 };
 505
 506 static inline int
 507 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 508                             struct nf_conntrack_tuple *tuple)
 509 {
 510         struct nfattr *tb[CTA_PROTO_MAX];
 511         struct nf_conntrack_protocol *proto;
 512         int ret = 0;
 513
 514         DEBUGP("entered %s\n", __FUNCTION__);
 515
 516         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 517
 518         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 519                 return -EINVAL;
 520
 521         if (!tb[CTA_PROTO_NUM-1])
 522                 return -EINVAL;
 523         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 524
 525         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 526
 527         if (likely(proto->nfattr_to_tuple))
 528                 ret = proto->nfattr_to_tuple(tb, tuple);
 529
 530         nf_ct_proto_put(proto);
 531
 532         return ret;
 533 }
 534
 535 static inline int
 536 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 537                       enum ctattr_tuple type, u_int8_t l3num)
 538 {
 539         struct nfattr *tb[CTA_TUPLE_MAX];
 540         int err;
 541
 542         DEBUGP("entered %s\n", __FUNCTION__);
 543
 544         memset(tuple, 0, sizeof(*tuple));
 545
 546         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 547
 548         if (!tb[CTA_TUPLE_IP-1])
 549                 return -EINVAL;
 550
 551         tuple->src.l3num = l3num;
 552
 553         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 554         if (err < 0)
 555                 return err;
 556
 557         if (!tb[CTA_TUPLE_PROTO-1])
 558                 return -EINVAL;
 559
 560         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 561         if (err < 0)
 562                 return err;
 563
 564         /* orig and expect tuples get DIR_ORIGINAL */
 565         if (type == CTA_TUPLE_REPLY)
 566                 tuple->dst.dir = IP_CT_DIR_REPLY;
 567         else
 568                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 569
 570         NF_CT_DUMP_TUPLE(tuple);
 571
 572         DEBUGP("leaving\n");
 573
 574         return 0;
 575 }
 576
 577 #ifdef CONFIG_IP_NF_NAT_NEEDED
 578 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 579         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 580         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 581 };
 582
 583 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 584                                      const struct nf_conn *ct,
 585                                      struct ip_nat_range *range)
 586 {
 587         struct nfattr *tb[CTA_PROTONAT_MAX];
 588         struct ip_nat_protocol *npt;
 589
 590         DEBUGP("entered %s\n", __FUNCTION__);
 591
 592         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 593
 594         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 595                 return -EINVAL;
 596
 597         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 598
 599         if (!npt->nfattr_to_range) {
 600                 ip_nat_proto_put(npt);
 601                 return 0;
 602         }
 603
 604         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 605         if (npt->nfattr_to_range(tb, range) > 0)
 606                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 607
 608         ip_nat_proto_put(npt);
 609
 610         DEBUGP("leaving\n");
 611         return 0;
 612 }
 613
 614 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 615         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 616         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 617 };
 618
 619 static inline int
 620 ctnetlink_parse_nat(struct nfattr *cda[],
 621                     const struct nf_conn *ct, struct ip_nat_range *range)
 622 {
 623         struct nfattr *tb[CTA_NAT_MAX];
 624         int err;
 625
 626         DEBUGP("entered %s\n", __FUNCTION__);
 627
 628         memset(range, 0, sizeof(*range));
 629
 630         nfattr_parse_nested(tb, CTA_NAT_MAX, cda[CTA_NAT-1]);
 631
 632         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 633                 return -EINVAL;
 634
 635         if (tb[CTA_NAT_MINIP-1])
 636                 range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 637
 638         if (!tb[CTA_NAT_MAXIP-1])
 639                 range->max_ip = range->min_ip;
 640         else
 641                 range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 642
 643         if (range->min_ip)
 644                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 645
 646         if (!tb[CTA_NAT_PROTO-1])
 647                 return 0;
 648
 649         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 650         if (err < 0)
 651                 return err;
 652
 653         DEBUGP("leaving\n");
 654         return 0;
 655 }
 656 #endif
 657
 658 static inline int
 659 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 660 {
 661         struct nfattr *tb[CTA_HELP_MAX];
 662
 663         DEBUGP("entered %s\n", __FUNCTION__);
 664
 665         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 666
 667         if (!tb[CTA_HELP_NAME-1])
 668                 return -EINVAL;
 669
 670         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 671
 672         return 0;
 673 }
 674
 675 static const size_t cta_min[CTA_MAX] = {
 676         [CTA_STATUS-1]          = sizeof(u_int32_t),
 677         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 678         [CTA_MARK-1]            = sizeof(u_int32_t),
 679         [CTA_USE-1]             = sizeof(u_int32_t),
 680         [CTA_ID-1]              = sizeof(u_int32_t)
 681 };
 682
 683 static int
 684 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 685                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 686 {
 687         struct nf_conntrack_tuple_hash *h;
 688         struct nf_conntrack_tuple tuple;
 689         struct nf_conn *ct;
 690         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 691         u_int8_t u3 = nfmsg->nfgen_family;
 692         int err = 0;
 693
 694         DEBUGP("entered %s\n", __FUNCTION__);
 695
 696         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 697                 return -EINVAL;
 698
 699         if (cda[CTA_TUPLE_ORIG-1])
 700                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 701         else if (cda[CTA_TUPLE_REPLY-1])
 702                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 703         else {
 704                 /* Flush the whole table */
 705                 nf_conntrack_flush();
 706                 return 0;
 707         }
 708
 709         if (err < 0)
 710                 return err;
 711
 712         h = nf_conntrack_find_get(&tuple, NULL);
 713         if (!h) {
 714                 DEBUGP("tuple not found in conntrack hash\n");
 715                 return -ENOENT;
 716         }
 717
 718         ct = nf_ct_tuplehash_to_ctrack(h);
 719
 720         if (cda[CTA_ID-1]) {
 721                 u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1]));
 722                 if (ct->id != id) {
 723                         nf_ct_put(ct);
 724                         return -ENOENT;
 725                 }
 726         }
 727         if (del_timer(&ct->timeout))
 728                 ct->timeout.function((unsigned long)ct);
 729
 730         nf_ct_put(ct);
 731         DEBUGP("leaving\n");
 732
 733         return 0;
 734 }
 735
 736 static int
 737 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 738                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 739 {
 740         struct nf_conntrack_tuple_hash *h;
 741         struct nf_conntrack_tuple tuple;
 742         struct nf_conn *ct;
 743         struct sk_buff *skb2 = NULL;
 744         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 745         u_int8_t u3 = nfmsg->nfgen_family;
 746         int err = 0;
 747
 748         DEBUGP("entered %s\n", __FUNCTION__);
 749
 750         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 751                 u32 rlen;
 752
 753                 if (nfmsg->nfgen_family != AF_INET)
 754                         return -EAFNOSUPPORT;
 755
 756                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) ==
 757                                         IPCTNL_MSG_CT_GET_CTRZERO) {
 758 #ifdef CONFIG_NF_CT_ACCT
 759                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 760                                                 ctnetlink_dump_table_w,
 761                                                 ctnetlink_done)) != 0)
 762                                 return -EINVAL;
 763 #else
 764                         return -ENOTSUPP;
 765 #endif
 766                 } else {
 767                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 768                                                         ctnetlink_dump_table,
 769                                                         ctnetlink_done)) != 0)
 770                         return -EINVAL;
 771                 }
 772
 773                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 774                 if (rlen > skb->len)
 775                         rlen = skb->len;
 776                 skb_pull(skb, rlen);
 777                 return 0;
 778         }
 779
 780         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 781                 return -EINVAL;
 782
 783         if (cda[CTA_TUPLE_ORIG-1])
 784                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 785         else if (cda[CTA_TUPLE_REPLY-1])
 786                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 787         else
 788                 return -EINVAL;
 789
 790         if (err < 0)
 791                 return err;
 792
 793         h = nf_conntrack_find_get(&tuple, NULL);
 794         if (!h) {
 795                 DEBUGP("tuple not found in conntrack hash");
 796                 return -ENOENT;
 797         }
 798         DEBUGP("tuple found\n");
 799         ct = nf_ct_tuplehash_to_ctrack(h);
 800
 801         err = -ENOMEM;
 802         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 803         if (!skb2) {
 804                 nf_ct_put(ct);
 805                 return -ENOMEM;
 806         }
 807         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
 808
 809         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 810                                   IPCTNL_MSG_CT_NEW, 1, ct);
 811         nf_ct_put(ct);
 812         if (err <= 0)
 813                 goto free;
 814
 815         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 816         if (err < 0)
 817                 goto out;
 818
 819         DEBUGP("leaving\n");
 820         return 0;
 821
 822 free:
 823         kfree_skb(skb2);
 824 out:
 825         return err;
 826 }
 827
 828 static inline int
 829 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 830 {
 831         unsigned long d;
 832         unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1]));
 833         d = ct->status ^ status;
 834
 835         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 836                 /* unchangeable */
 837                 return -EINVAL;
 838
 839         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 840                 /* SEEN_REPLY bit can only be set */
 841                 return -EINVAL;
 842
 843
 844         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 845                 /* ASSURED bit can only be set */
 846                 return -EINVAL;
 847
 848         if (cda[CTA_NAT-1]) {
 849 #ifndef CONFIG_IP_NF_NAT_NEEDED
 850                 return -EINVAL;
 851 #else
 852                 unsigned int hooknum;
 853                 struct ip_nat_range range;
 854
 855                 if (ctnetlink_parse_nat(cda, ct, &range) < 0)
 856                         return -EINVAL;
 857
 858                 DEBUGP("NAT: %u.%u.%u.%u-%u.%u.%u.%u:%u-%u\n",
 859                        NIPQUAD(range.min_ip), NIPQUAD(range.max_ip),
 860                        htons(range.min.all), htons(range.max.all));
 861
 862                 /* This is tricky but it works. ip_nat_setup_info needs the
 863                  * hook number as parameter, so let's do the correct
 864                  * conversion and run away */
 865                 if (status & IPS_SRC_NAT_DONE)
 866                         hooknum = NF_IP_POST_ROUTING; /* IP_NAT_MANIP_SRC */
 867                 else if (status & IPS_DST_NAT_DONE)
 868                         hooknum = NF_IP_PRE_ROUTING;  /* IP_NAT_MANIP_DST */
 869                 else
 870                         return -EINVAL; /* Missing NAT flags */
 871
 872                 DEBUGP("NAT status: %lu\n",
 873                        status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK));
 874
 875                 if (ip_nat_initialized(ct, HOOK2MANIP(hooknum)))
 876                         return -EEXIST;
 877                 ip_nat_setup_info(ct, &range, hooknum);
 878
 879                 DEBUGP("NAT status after setup_info: %lu\n",
 880                        ct->status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK));
 881 #endif
 882         }
 883
 884         /* Be careful here, modifying NAT bits can screw up things,
 885          * so don't let users modify them directly if they don't pass
 886          * ip_nat_range. */
 887         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 888         return 0;
 889 }
 890
 891
 892 static inline int
 893 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 894 {
 895         struct nf_conntrack_helper *helper;
 896         char *helpname;
 897         int err;
 898
 899         DEBUGP("entered %s\n", __FUNCTION__);
 900
 901         /* don't change helper of sibling connections */
 902         if (ct->master)
 903                 return -EINVAL;
 904
 905         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 906         if (err < 0)
 907                 return err;
 908
 909         helper = __nf_conntrack_helper_find_byname(helpname);
 910         if (!helper) {
 911                 if (!strcmp(helpname, ""))
 912                         helper = NULL;
 913                 else
 914                         return -EINVAL;
 915         }
 916
 917         if (ct->helper) {
 918                 if (!helper) {
 919                         /* we had a helper before ... */
 920                         nf_ct_remove_expectations(ct);
 921                         ct->helper = NULL;
 922                 } else {
 923                         /* need to zero data of old helper */
 924                         memset(&ct->help, 0, sizeof(ct->help));
 925                 }
 926         }
 927
 928         ct->helper = helper;
 929
 930         return 0;
 931 }
 932
 933 static inline int
 934 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 935 {
 936         u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 937
 938         if (!del_timer(&ct->timeout))
 939                 return -ETIME;
 940
 941         ct->timeout.expires = jiffies + timeout * HZ;
 942         add_timer(&ct->timeout);
 943
 944         return 0;
 945 }
 946
 947 static inline int
 948 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 949 {
 950         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 951         struct nf_conntrack_protocol *proto;
 952         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 953         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 954         int err = 0;
 955
 956         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 957
 958         proto = nf_ct_proto_find_get(l3num, npt);
 959
 960         if (proto->from_nfattr)
 961                 err = proto->from_nfattr(tb, ct);
 962         nf_ct_proto_put(proto);
 963
 964         return err;
 965 }
 966
 967 static int
 968 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
 969 {
 970         int err;
 971
 972         DEBUGP("entered %s\n", __FUNCTION__);
 973
 974         if (cda[CTA_HELP-1]) {
 975                 err = ctnetlink_change_helper(ct, cda);
 976                 if (err < 0)
 977                         return err;
 978         }
 979
 980         if (cda[CTA_TIMEOUT-1]) {
 981                 err = ctnetlink_change_timeout(ct, cda);
 982                 if (err < 0)
 983                         return err;
 984         }
 985
 986         if (cda[CTA_STATUS-1]) {
 987                 err = ctnetlink_change_status(ct, cda);
 988                 if (err < 0)
 989                         return err;
 990         }
 991
 992         if (cda[CTA_PROTOINFO-1]) {
 993                 err = ctnetlink_change_protoinfo(ct, cda);
 994                 if (err < 0)
 995                         return err;
 996         }
 997
 998 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
 999         if (cda[CTA_MARK-1])
1000                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1001 #endif
1002
1003         DEBUGP("all done\n");
1004         return 0;
1005 }
1006
1007 static int
1008 ctnetlink_create_conntrack(struct nfattr *cda[],
1009                            struct nf_conntrack_tuple *otuple,
1010                            struct nf_conntrack_tuple *rtuple)
1011 {
1012         struct nf_conn *ct;
1013         int err = -EINVAL;
1014
1015         DEBUGP("entered %s\n", __FUNCTION__);
1016
1017         ct = nf_conntrack_alloc(otuple, rtuple);
1018         if (ct == NULL || IS_ERR(ct))
1019                 return -ENOMEM;
1020
1021         if (!cda[CTA_TIMEOUT-1])
1022                 goto err;
1023         ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
1024
1025         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1026         ct->status |= IPS_CONFIRMED;
1027
1028         err = ctnetlink_change_status(ct, cda);
1029         if (err < 0)
1030                 goto err;
1031
1032         if (cda[CTA_PROTOINFO-1]) {
1033                 err = ctnetlink_change_protoinfo(ct, cda);
1034                 if (err < 0)
1035                         return err;
1036         }
1037
1038 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
1039         if (cda[CTA_MARK-1])
1040                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1041 #endif
1042
1043         ct->helper = nf_ct_helper_find_get(rtuple);
1044
1045         add_timer(&ct->timeout);
1046         nf_conntrack_hash_insert(ct);
1047
1048         if (ct->helper)
1049                 nf_ct_helper_put(ct->helper);
1050
1051         DEBUGP("conntrack with id %u inserted\n", ct->id);
1052         return 0;
1053
1054 err:
1055         nf_conntrack_free(ct);
1056         return err;
1057 }
1058
1059 static int
1060 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1061                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1062 {
1063         struct nf_conntrack_tuple otuple, rtuple;
1064         struct nf_conntrack_tuple_hash *h = NULL;
1065         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1066         u_int8_t u3 = nfmsg->nfgen_family;
1067         int err = 0;
1068
1069         DEBUGP("entered %s\n", __FUNCTION__);
1070
1071         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1072                 return -EINVAL;
1073
1074         if (cda[CTA_TUPLE_ORIG-1]) {
1075                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1076                 if (err < 0)
1077                         return err;
1078         }
1079
1080         if (cda[CTA_TUPLE_REPLY-1]) {
1081                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1082                 if (err < 0)
1083                         return err;
1084         }
1085
1086         write_lock_bh(&nf_conntrack_lock);
1087         if (cda[CTA_TUPLE_ORIG-1])
1088                 h = __nf_conntrack_find(&otuple, NULL);
1089         else if (cda[CTA_TUPLE_REPLY-1])
1090                 h = __nf_conntrack_find(&rtuple, NULL);
1091
1092         if (h == NULL) {
1093                 write_unlock_bh(&nf_conntrack_lock);
1094                 DEBUGP("no such conntrack, create new\n");
1095                 err = -ENOENT;
1096                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1097                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1098                 return err;
1099         }
1100         /* implicit 'else' */
1101
1102         /* we only allow nat config for new conntracks */
1103         if (cda[CTA_NAT-1]) {
1104                 err = -EINVAL;
1105                 goto out_unlock;
1106         }
1107
1108         /* We manipulate the conntrack inside the global conntrack table lock,
1109          * so there's no need to increase the refcount */
1110         DEBUGP("conntrack found\n");
1111         err = -EEXIST;
1112         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1113                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1114
1115 out_unlock:
1116         write_unlock_bh(&nf_conntrack_lock);
1117         return err;
1118 }
1119
1120 /***********************************************************************
1121  * EXPECT
1122  ***********************************************************************/
1123
1124 static inline int
1125 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1126                          const struct nf_conntrack_tuple *tuple,
1127                          enum ctattr_expect type)
1128 {
1129         struct nfattr *nest_parms = NFA_NEST(skb, type);
1130
1131         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1132                 goto nfattr_failure;
1133
1134         NFA_NEST_END(skb, nest_parms);
1135
1136         return 0;
1137
1138 nfattr_failure:
1139         return -1;
1140 }
1141
1142 static inline int
1143 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1144                           const struct nf_conntrack_expect *exp)
1145 {
1146         struct nf_conn *master = exp->master;
1147         u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1148         u_int32_t id = htonl(exp->id);
1149
1150         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1151                 goto nfattr_failure;
1152         if (ctnetlink_exp_dump_tuple(skb, &exp->mask, CTA_EXPECT_MASK) < 0)
1153                 goto nfattr_failure;
1154         if (ctnetlink_exp_dump_tuple(skb,
1155                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1156                                  CTA_EXPECT_MASTER) < 0)
1157                 goto nfattr_failure;
1158
1159         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1160         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1161
1162         return 0;
1163
1164 nfattr_failure:
1165         return -1;
1166 }
1167
1168 static int
1169 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1170                     int event,
1171                     int nowait,
1172                     const struct nf_conntrack_expect *exp)
1173 {
1174         struct nlmsghdr *nlh;
1175         struct nfgenmsg *nfmsg;
1176         unsigned char *b;
1177
1178         b = skb->tail;
1179
1180         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1181         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1182         nfmsg  = NLMSG_DATA(nlh);
1183
1184         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1185         nfmsg->nfgen_family = exp->tuple.src.l3num;
1186         nfmsg->version      = NFNETLINK_V0;
1187         nfmsg->res_id       = 0;
1188
1189         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1190                 goto nfattr_failure;
1191
1192         nlh->nlmsg_len = skb->tail - b;
1193         return skb->len;
1194
1195 nlmsg_failure:
1196 nfattr_failure:
1197         skb_trim(skb, b - skb->data);
1198         return -1;
1199 }
1200
1201 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1202 static int ctnetlink_expect_event(struct notifier_block *this,
1203                                   unsigned long events, void *ptr)
1204 {
1205         struct nlmsghdr *nlh;
1206         struct nfgenmsg *nfmsg;
1207         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1208         struct sk_buff *skb;
1209         unsigned int type;
1210         unsigned char *b;
1211         int flags = 0;
1212
1213         if (events & IPEXP_NEW) {
1214                 type = IPCTNL_MSG_EXP_NEW;
1215                 flags = NLM_F_CREATE|NLM_F_EXCL;
1216         } else
1217                 return NOTIFY_DONE;
1218
1219         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1220         if (!skb)
1221                 return NOTIFY_DONE;
1222
1223         b = skb->tail;
1224
1225         type |= NFNL_SUBSYS_CTNETLINK << 8;
1226         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1227         nfmsg = NLMSG_DATA(nlh);
1228
1229         nlh->nlmsg_flags    = flags;
1230         nfmsg->nfgen_family = exp->tuple.src.l3num;
1231         nfmsg->version      = NFNETLINK_V0;
1232         nfmsg->res_id       = 0;
1233
1234         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1235                 goto nfattr_failure;
1236
1237         nlh->nlmsg_len = skb->tail - b;
1238         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1239         return NOTIFY_DONE;
1240
1241 nlmsg_failure:
1242 nfattr_failure:
1243         kfree_skb(skb);
1244         return NOTIFY_DONE;
1245 }
1246 #endif
1247
1248 static int
1249 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1250 {
1251         struct nf_conntrack_expect *exp = NULL;
1252         struct list_head *i;
1253         u_int32_t *id = (u_int32_t *) &cb->args[0];
1254
1255         DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id);
1256
1257         read_lock_bh(&nf_conntrack_lock);
1258         list_for_each_prev(i, &nf_conntrack_expect_list) {
1259                 exp = (struct nf_conntrack_expect *) i;
1260                 if (exp->id <= *id)
1261                         continue;
1262                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1263                                             cb->nlh->nlmsg_seq,
1264                                             IPCTNL_MSG_EXP_NEW,
1265                                             1, exp) < 0)
1266                         goto out;
1267                 *id = exp->id;
1268         }
1269 out:
1270         read_unlock_bh(&nf_conntrack_lock);
1271
1272         DEBUGP("leaving, last id=%llu\n", *id);
1273
1274         return skb->len;
1275 }
1276
1277 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1278         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1279         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1280 };
1281
1282 static int
1283 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1284                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1285 {
1286         struct nf_conntrack_tuple tuple;
1287         struct nf_conntrack_expect *exp;
1288         struct sk_buff *skb2;
1289         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1290         u_int8_t u3 = nfmsg->nfgen_family;
1291         int err = 0;
1292
1293         DEBUGP("entered %s\n", __FUNCTION__);
1294
1295         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1296                 return -EINVAL;
1297
1298         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1299                 u32 rlen;
1300
1301                 if (nfmsg->nfgen_family != AF_INET)
1302                         return -EAFNOSUPPORT;
1303
1304                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1305                                                 ctnetlink_exp_dump_table,
1306                                                 ctnetlink_done)) != 0)
1307                         return -EINVAL;
1308                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1309                 if (rlen > skb->len)
1310                         rlen = skb->len;
1311                 skb_pull(skb, rlen);
1312                 return 0;
1313         }
1314
1315         if (cda[CTA_EXPECT_MASTER-1])
1316                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1317         else
1318                 return -EINVAL;
1319
1320         if (err < 0)
1321                 return err;
1322
1323         exp = nf_conntrack_expect_find(&tuple);
1324         if (!exp)
1325                 return -ENOENT;
1326
1327         if (cda[CTA_EXPECT_ID-1]) {
1328                 u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1329                 if (exp->id != ntohl(id)) {
1330                         nf_conntrack_expect_put(exp);
1331                         return -ENOENT;
1332                 }
1333         }
1334
1335         err = -ENOMEM;
1336         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1337         if (!skb2)
1338                 goto out;
1339         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
1340
1341         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1342                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1343                                       1, exp);
1344         if (err <= 0)
1345                 goto free;
1346
1347         nf_conntrack_expect_put(exp);
1348
1349         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1350
1351 free:
1352         kfree_skb(skb2);
1353 out:
1354         nf_conntrack_expect_put(exp);
1355         return err;
1356 }
1357
1358 static int
1359 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1360                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1361 {
1362         struct nf_conntrack_expect *exp, *tmp;
1363         struct nf_conntrack_tuple tuple;
1364         struct nf_conntrack_helper *h;
1365         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1366         u_int8_t u3 = nfmsg->nfgen_family;
1367         int err;
1368
1369         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1370                 return -EINVAL;
1371
1372         if (cda[CTA_EXPECT_TUPLE-1]) {
1373                 /* delete a single expect by tuple */
1374                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1375                 if (err < 0)
1376                         return err;
1377
1378                 /* bump usage count to 2 */
1379                 exp = nf_conntrack_expect_find(&tuple);
1380                 if (!exp)
1381                         return -ENOENT;
1382
1383                 if (cda[CTA_EXPECT_ID-1]) {
1384                         u_int32_t id =
1385                                 *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1386                         if (exp->id != ntohl(id)) {
1387                                 nf_conntrack_expect_put(exp);
1388                                 return -ENOENT;
1389                         }
1390                 }
1391
1392                 /* after list removal, usage count == 1 */
1393                 nf_conntrack_unexpect_related(exp);
1394                 /* have to put what we 'get' above.
1395                  * after this line usage count == 0 */
1396                 nf_conntrack_expect_put(exp);
1397         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1398                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1399
1400                 /* delete all expectations for this helper */
1401                 write_lock_bh(&nf_conntrack_lock);
1402                 h = __nf_conntrack_helper_find_byname(name);
1403                 if (!h) {
1404                         write_unlock_bh(&nf_conntrack_lock);
1405                         return -EINVAL;
1406                 }
1407                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1408                                          list) {
1409                         if (exp->master->helper == h
1410                             && del_timer(&exp->timeout)) {
1411                                 nf_ct_unlink_expect(exp);
1412                                 nf_conntrack_expect_put(exp);
1413                         }
1414                 }
1415                 write_unlock_bh(&nf_conntrack_lock);
1416         } else {
1417                 /* This basically means we have to flush everything*/
1418                 write_lock_bh(&nf_conntrack_lock);
1419                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1420                                          list) {
1421                         if (del_timer(&exp->timeout)) {
1422                                 nf_ct_unlink_expect(exp);
1423                                 nf_conntrack_expect_put(exp);
1424                         }
1425                 }
1426                 write_unlock_bh(&nf_conntrack_lock);
1427         }
1428
1429         return 0;
1430 }
1431 static int
1432 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1433 {
1434         return -EOPNOTSUPP;
1435 }
1436
1437 static int
1438 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1439 {
1440         struct nf_conntrack_tuple tuple, mask, master_tuple;
1441         struct nf_conntrack_tuple_hash *h = NULL;
1442         struct nf_conntrack_expect *exp;
1443         struct nf_conn *ct;
1444         int err = 0;
1445
1446         DEBUGP("entered %s\n", __FUNCTION__);
1447
1448         /* caller guarantees that those three CTA_EXPECT_* exist */
1449         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1450         if (err < 0)
1451                 return err;
1452         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1453         if (err < 0)
1454                 return err;
1455         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1456         if (err < 0)
1457                 return err;
1458
1459         /* Look for master conntrack of this expectation */
1460         h = nf_conntrack_find_get(&master_tuple, NULL);
1461         if (!h)
1462                 return -ENOENT;
1463         ct = nf_ct_tuplehash_to_ctrack(h);
1464
1465         if (!ct->helper) {
1466                 /* such conntrack hasn't got any helper, abort */
1467                 err = -EINVAL;
1468                 goto out;
1469         }
1470
1471         exp = nf_conntrack_expect_alloc(ct);
1472         if (!exp) {
1473                 err = -ENOMEM;
1474                 goto out;
1475         }
1476
1477         exp->expectfn = NULL;
1478         exp->flags = 0;
1479         exp->master = ct;
1480         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1481         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1482
1483         err = nf_conntrack_expect_related(exp);
1484         nf_conntrack_expect_put(exp);
1485
1486 out:
1487         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1488         return err;
1489 }
1490
1491 static int
1492 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1493                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1494 {
1495         struct nf_conntrack_tuple tuple;
1496         struct nf_conntrack_expect *exp;
1497         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1498         u_int8_t u3 = nfmsg->nfgen_family;
1499         int err = 0;
1500
1501         DEBUGP("entered %s\n", __FUNCTION__);
1502
1503         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1504                 return -EINVAL;
1505
1506         if (!cda[CTA_EXPECT_TUPLE-1]
1507             || !cda[CTA_EXPECT_MASK-1]
1508             || !cda[CTA_EXPECT_MASTER-1])
1509                 return -EINVAL;
1510
1511         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1512         if (err < 0)
1513                 return err;
1514
1515         write_lock_bh(&nf_conntrack_lock);
1516         exp = __nf_conntrack_expect_find(&tuple);
1517
1518         if (!exp) {
1519                 write_unlock_bh(&nf_conntrack_lock);
1520                 err = -ENOENT;
1521                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1522                         err = ctnetlink_create_expect(cda, u3);
1523                 return err;
1524         }
1525
1526         err = -EEXIST;
1527         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1528                 err = ctnetlink_change_expect(exp, cda);
1529         write_unlock_bh(&nf_conntrack_lock);
1530
1531         DEBUGP("leaving\n");
1532
1533         return err;
1534 }
1535
1536 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1537 static struct notifier_block ctnl_notifier = {
1538         .notifier_call  = ctnetlink_conntrack_event,
1539 };
1540
1541 static struct notifier_block ctnl_notifier_exp = {
1542         .notifier_call  = ctnetlink_expect_event,
1543 };
1544 #endif
1545
1546 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1547         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1548                                             .attr_count = CTA_MAX, },
1549         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1550                                             .attr_count = CTA_MAX, },
1551         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1552                                             .attr_count = CTA_MAX, },
1553         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1554                                             .attr_count = CTA_MAX, },
1555 };
1556
1557 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1558         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1559                                             .attr_count = CTA_EXPECT_MAX, },
1560         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1561                                             .attr_count = CTA_EXPECT_MAX, },
1562         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1563                                             .attr_count = CTA_EXPECT_MAX, },
1564 };
1565
1566 static struct nfnetlink_subsystem ctnl_subsys = {
1567         .name                           = "conntrack",
1568         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1569         .cb_count                       = IPCTNL_MSG_MAX,
1570         .cb                             = ctnl_cb,
1571 };
1572
1573 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1574         .name                           = "conntrack_expect",
1575         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1576         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1577         .cb                             = ctnl_exp_cb,
1578 };
1579
1580 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1581
1582 static int __init ctnetlink_init(void)
1583 {
1584         int ret;
1585
1586         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1587         ret = nfnetlink_subsys_register(&ctnl_subsys);
1588         if (ret < 0) {
1589                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1590                 goto err_out;
1591         }
1592
1593         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1594         if (ret < 0) {
1595                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1596                 goto err_unreg_subsys;
1597         }
1598
1599 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1600         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1601         if (ret < 0) {
1602                 printk("ctnetlink_init: cannot register notifier.\n");
1603                 goto err_unreg_exp_subsys;
1604         }
1605
1606         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1607         if (ret < 0) {
1608                 printk("ctnetlink_init: cannot expect register notifier.\n");
1609                 goto err_unreg_notifier;
1610         }
1611 #endif
1612
1613         return 0;
1614
1615 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1616 err_unreg_notifier:
1617         nf_conntrack_unregister_notifier(&ctnl_notifier);
1618 err_unreg_exp_subsys:
1619         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1620 #endif
1621 err_unreg_subsys:
1622         nfnetlink_subsys_unregister(&ctnl_subsys);
1623 err_out:
1624         return ret;
1625 }
1626
1627 static void __exit ctnetlink_exit(void)
1628 {
1629         printk("ctnetlink: unregistering from nfnetlink.\n");
1630
1631 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1632         nf_conntrack_unregister_notifier(&ctnl_notifier_exp);
1633         nf_conntrack_unregister_notifier(&ctnl_notifier);
1634 #endif
1635
1636         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1637         nfnetlink_subsys_unregister(&ctnl_subsys);
1638         return;
1639 }
1640
1641 module_init(ctnetlink_init);
1642 module_exit(ctnetlink_exit);