git.oblomov.eu Git - linux-2.6/blob - net/netfilter/nf_conntrack_netlink.c

   1 /* Connection tracking via netlink socket. Allows for user space
   2  * protocol helpers and general trouble making from userspace.
   3  *
   4  * (C) 2001 by Jay Schulist <jschlst@samba.org>
   5  * (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
   6  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
   7  * (C) 2005 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[] = "0.93";
  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         const struct nf_conn_help *help = nfct_help(ct);
 169
 170         if (!help || !help->helper)
 171                 return 0;
 172
 173         nest_helper = NFA_NEST(skb, CTA_HELP);
 174         NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
 175
 176         if (help->helper->to_nfattr)
 177                 help->helper->to_nfattr(skb, ct);
 178
 179         NFA_NEST_END(skb, nest_helper);
 180
 181         return 0;
 182
 183 nfattr_failure:
 184         return -1;
 185 }
 186
 187 #ifdef CONFIG_NF_CT_ACCT
 188 static inline int
 189 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 190                         enum ip_conntrack_dir dir)
 191 {
 192         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 193         struct nfattr *nest_count = NFA_NEST(skb, type);
 194         u_int32_t tmp;
 195
 196         tmp = htonl(ct->counters[dir].packets);
 197         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 198
 199         tmp = htonl(ct->counters[dir].bytes);
 200         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 201
 202         NFA_NEST_END(skb, nest_count);
 203
 204         return 0;
 205
 206 nfattr_failure:
 207         return -1;
 208 }
 209 #else
 210 #define ctnetlink_dump_counters(a, b, c) (0)
 211 #endif
 212
 213 #ifdef CONFIG_NF_CONNTRACK_MARK
 214 static inline int
 215 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 216 {
 217         u_int32_t mark = htonl(ct->mark);
 218
 219         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 220         return 0;
 221
 222 nfattr_failure:
 223         return -1;
 224 }
 225 #else
 226 #define ctnetlink_dump_mark(a, b) (0)
 227 #endif
 228
 229 static inline int
 230 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 231 {
 232         u_int32_t id = htonl(ct->id);
 233         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 234         return 0;
 235
 236 nfattr_failure:
 237         return -1;
 238 }
 239
 240 static inline int
 241 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 242 {
 243         u_int32_t use = htonl(atomic_read(&ct->ct_general.use));
 244
 245         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 246         return 0;
 247
 248 nfattr_failure:
 249         return -1;
 250 }
 251
 252 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 253
 254 static int
 255 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 256                     int event, int nowait,
 257                     const struct nf_conn *ct)
 258 {
 259         struct nlmsghdr *nlh;
 260         struct nfgenmsg *nfmsg;
 261         struct nfattr *nest_parms;
 262         unsigned char *b;
 263
 264         b = skb->tail;
 265
 266         event |= NFNL_SUBSYS_CTNETLINK << 8;
 267         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 268         nfmsg  = NLMSG_DATA(nlh);
 269
 270         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 271         nfmsg->nfgen_family =
 272                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 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_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 nf_conn *ct = (struct nf_conn *)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 == &nf_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 |
 333                       IPCT_PROTOINFO |
 334                       IPCT_HELPER |
 335                       IPCT_HELPINFO |
 336                       IPCT_NATINFO)) {
 337                 type = IPCTNL_MSG_CT_NEW;
 338                 group = NFNLGRP_CONNTRACK_UPDATE;
 339         } else
 340                 return NOTIFY_DONE;
 341
 342         if (!nfnetlink_has_listeners(group))
 343                 return NOTIFY_DONE;
 344
 345         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 346         if (!skb)
 347                 return NOTIFY_DONE;
 348
 349         b = skb->tail;
 350
 351         type |= NFNL_SUBSYS_CTNETLINK << 8;
 352         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 353         nfmsg = NLMSG_DATA(nlh);
 354
 355         nlh->nlmsg_flags    = flags;
 356         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 357         nfmsg->version  = NFNETLINK_V0;
 358         nfmsg->res_id   = 0;
 359
 360         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 361         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 362                 goto nfattr_failure;
 363         NFA_NEST_END(skb, nest_parms);
 364
 365         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 366         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 367                 goto nfattr_failure;
 368         NFA_NEST_END(skb, nest_parms);
 369
 370         /* NAT stuff is now a status flag */
 371         if ((events & IPCT_STATUS || events & IPCT_NATINFO)
 372             && ctnetlink_dump_status(skb, ct) < 0)
 373                 goto nfattr_failure;
 374         if (events & IPCT_REFRESH
 375             && ctnetlink_dump_timeout(skb, ct) < 0)
 376                 goto nfattr_failure;
 377         if (events & IPCT_PROTOINFO
 378             && ctnetlink_dump_protoinfo(skb, ct) < 0)
 379                 goto nfattr_failure;
 380         if (events & IPCT_HELPINFO
 381             && ctnetlink_dump_helpinfo(skb, ct) < 0)
 382                 goto nfattr_failure;
 383
 384         if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 385             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 386                 goto nfattr_failure;
 387
 388         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_NF_CONNTRACK_EVENTS */
 398
 399 static int ctnetlink_done(struct netlink_callback *cb)
 400 {
 401         DEBUGP("entered %s\n", __FUNCTION__);
 402         return 0;
 403 }
 404
 405 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 406
 407 static int
 408 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 409 {
 410         struct nf_conn *ct = NULL;
 411         struct nf_conntrack_tuple_hash *h;
 412         struct list_head *i;
 413         u_int32_t *id = (u_int32_t *) &cb->args[1];
 414         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 415         u_int8_t l3proto = nfmsg->nfgen_family;
 416
 417         DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__,
 418                         cb->args[0], *id);
 419
 420         read_lock_bh(&nf_conntrack_lock);
 421         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 422                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 423                         h = (struct nf_conntrack_tuple_hash *) i;
 424                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 425                                 continue;
 426                         ct = nf_ct_tuplehash_to_ctrack(h);
 427                         /* Dump entries of a given L3 protocol number.
 428                          * If it is not specified, ie. l3proto == 0,
 429                          * then dump everything. */
 430                         if (l3proto && L3PROTO(ct) != l3proto)
 431                                 continue;
 432                         if (ct->id <= *id)
 433                                 continue;
 434                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 435                                                 cb->nlh->nlmsg_seq,
 436                                                 IPCTNL_MSG_CT_NEW,
 437                                                 1, ct) < 0)
 438                                 goto out;
 439                         *id = ct->id;
 440                 }
 441         }
 442 out:
 443         read_unlock_bh(&nf_conntrack_lock);
 444
 445         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 446
 447         return skb->len;
 448 }
 449
 450 #ifdef CONFIG_NF_CT_ACCT
 451 static int
 452 ctnetlink_dump_table_w(struct sk_buff *skb, struct netlink_callback *cb)
 453 {
 454         struct nf_conn *ct = NULL;
 455         struct nf_conntrack_tuple_hash *h;
 456         struct list_head *i;
 457         u_int32_t *id = (u_int32_t *) &cb->args[1];
 458         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 459         u_int8_t l3proto = nfmsg->nfgen_family;
 460
 461         DEBUGP("entered %s, last bucket=%u id=%u\n", __FUNCTION__,
 462                         cb->args[0], *id);
 463
 464         write_lock_bh(&nf_conntrack_lock);
 465         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 466                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 467                         h = (struct nf_conntrack_tuple_hash *) i;
 468                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 469                                 continue;
 470                         ct = nf_ct_tuplehash_to_ctrack(h);
 471                         if (l3proto && L3PROTO(ct) != l3proto)
 472                                 continue;
 473                         if (ct->id <= *id)
 474                                 continue;
 475                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 476                                                 cb->nlh->nlmsg_seq,
 477                                                 IPCTNL_MSG_CT_NEW,
 478                                                 1, ct) < 0)
 479                                 goto out;
 480                         *id = ct->id;
 481
 482                         memset(&ct->counters, 0, sizeof(ct->counters));
 483                 }
 484         }
 485 out:
 486         write_unlock_bh(&nf_conntrack_lock);
 487
 488         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 489
 490         return skb->len;
 491 }
 492 #endif
 493
 494 static inline int
 495 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 496 {
 497         struct nfattr *tb[CTA_IP_MAX];
 498         struct nf_conntrack_l3proto *l3proto;
 499         int ret = 0;
 500
 501         DEBUGP("entered %s\n", __FUNCTION__);
 502
 503         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 504
 505         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 506
 507         if (likely(l3proto->nfattr_to_tuple))
 508                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 509
 510         nf_ct_l3proto_put(l3proto);
 511
 512         DEBUGP("leaving\n");
 513
 514         return ret;
 515 }
 516
 517 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 518         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 519 };
 520
 521 static inline int
 522 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 523                             struct nf_conntrack_tuple *tuple)
 524 {
 525         struct nfattr *tb[CTA_PROTO_MAX];
 526         struct nf_conntrack_protocol *proto;
 527         int ret = 0;
 528
 529         DEBUGP("entered %s\n", __FUNCTION__);
 530
 531         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 532
 533         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 534                 return -EINVAL;
 535
 536         if (!tb[CTA_PROTO_NUM-1])
 537                 return -EINVAL;
 538         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 539
 540         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 541
 542         if (likely(proto->nfattr_to_tuple))
 543                 ret = proto->nfattr_to_tuple(tb, tuple);
 544
 545         nf_ct_proto_put(proto);
 546
 547         return ret;
 548 }
 549
 550 static inline int
 551 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 552                       enum ctattr_tuple type, u_int8_t l3num)
 553 {
 554         struct nfattr *tb[CTA_TUPLE_MAX];
 555         int err;
 556
 557         DEBUGP("entered %s\n", __FUNCTION__);
 558
 559         memset(tuple, 0, sizeof(*tuple));
 560
 561         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 562
 563         if (!tb[CTA_TUPLE_IP-1])
 564                 return -EINVAL;
 565
 566         tuple->src.l3num = l3num;
 567
 568         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 569         if (err < 0)
 570                 return err;
 571
 572         if (!tb[CTA_TUPLE_PROTO-1])
 573                 return -EINVAL;
 574
 575         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 576         if (err < 0)
 577                 return err;
 578
 579         /* orig and expect tuples get DIR_ORIGINAL */
 580         if (type == CTA_TUPLE_REPLY)
 581                 tuple->dst.dir = IP_CT_DIR_REPLY;
 582         else
 583                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 584
 585         NF_CT_DUMP_TUPLE(tuple);
 586
 587         DEBUGP("leaving\n");
 588
 589         return 0;
 590 }
 591
 592 #ifdef CONFIG_IP_NF_NAT_NEEDED
 593 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 594         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 595         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 596 };
 597
 598 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 599                                      const struct nf_conn *ct,
 600                                      struct ip_nat_range *range)
 601 {
 602         struct nfattr *tb[CTA_PROTONAT_MAX];
 603         struct ip_nat_protocol *npt;
 604
 605         DEBUGP("entered %s\n", __FUNCTION__);
 606
 607         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 608
 609         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 610                 return -EINVAL;
 611
 612         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 613
 614         if (!npt->nfattr_to_range) {
 615                 ip_nat_proto_put(npt);
 616                 return 0;
 617         }
 618
 619         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 620         if (npt->nfattr_to_range(tb, range) > 0)
 621                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 622
 623         ip_nat_proto_put(npt);
 624
 625         DEBUGP("leaving\n");
 626         return 0;
 627 }
 628
 629 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 630         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 631         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 632 };
 633
 634 static inline int
 635 ctnetlink_parse_nat(struct nfattr *cda[],
 636                     const struct nf_conn *ct, struct ip_nat_range *range)
 637 {
 638         struct nfattr *tb[CTA_NAT_MAX];
 639         int err;
 640
 641         DEBUGP("entered %s\n", __FUNCTION__);
 642
 643         memset(range, 0, sizeof(*range));
 644
 645         nfattr_parse_nested(tb, CTA_NAT_MAX, cda[CTA_NAT-1]);
 646
 647         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 648                 return -EINVAL;
 649
 650         if (tb[CTA_NAT_MINIP-1])
 651                 range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 652
 653         if (!tb[CTA_NAT_MAXIP-1])
 654                 range->max_ip = range->min_ip;
 655         else
 656                 range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 657
 658         if (range->min_ip)
 659                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 660
 661         if (!tb[CTA_NAT_PROTO-1])
 662                 return 0;
 663
 664         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 665         if (err < 0)
 666                 return err;
 667
 668         DEBUGP("leaving\n");
 669         return 0;
 670 }
 671 #endif
 672
 673 static inline int
 674 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 675 {
 676         struct nfattr *tb[CTA_HELP_MAX];
 677
 678         DEBUGP("entered %s\n", __FUNCTION__);
 679
 680         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 681
 682         if (!tb[CTA_HELP_NAME-1])
 683                 return -EINVAL;
 684
 685         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 686
 687         return 0;
 688 }
 689
 690 static const size_t cta_min[CTA_MAX] = {
 691         [CTA_STATUS-1]          = sizeof(u_int32_t),
 692         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 693         [CTA_MARK-1]            = sizeof(u_int32_t),
 694         [CTA_USE-1]             = sizeof(u_int32_t),
 695         [CTA_ID-1]              = sizeof(u_int32_t)
 696 };
 697
 698 static int
 699 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 700                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 701 {
 702         struct nf_conntrack_tuple_hash *h;
 703         struct nf_conntrack_tuple tuple;
 704         struct nf_conn *ct;
 705         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 706         u_int8_t u3 = nfmsg->nfgen_family;
 707         int err = 0;
 708
 709         DEBUGP("entered %s\n", __FUNCTION__);
 710
 711         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 712                 return -EINVAL;
 713
 714         if (cda[CTA_TUPLE_ORIG-1])
 715                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 716         else if (cda[CTA_TUPLE_REPLY-1])
 717                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 718         else {
 719                 /* Flush the whole table */
 720                 nf_conntrack_flush();
 721                 return 0;
 722         }
 723
 724         if (err < 0)
 725                 return err;
 726
 727         h = nf_conntrack_find_get(&tuple, NULL);
 728         if (!h) {
 729                 DEBUGP("tuple not found in conntrack hash\n");
 730                 return -ENOENT;
 731         }
 732
 733         ct = nf_ct_tuplehash_to_ctrack(h);
 734
 735         if (cda[CTA_ID-1]) {
 736                 u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1]));
 737                 if (ct->id != id) {
 738                         nf_ct_put(ct);
 739                         return -ENOENT;
 740                 }
 741         }
 742         if (del_timer(&ct->timeout))
 743                 ct->timeout.function((unsigned long)ct);
 744
 745         nf_ct_put(ct);
 746         DEBUGP("leaving\n");
 747
 748         return 0;
 749 }
 750
 751 static int
 752 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 753                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 754 {
 755         struct nf_conntrack_tuple_hash *h;
 756         struct nf_conntrack_tuple tuple;
 757         struct nf_conn *ct;
 758         struct sk_buff *skb2 = NULL;
 759         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 760         u_int8_t u3 = nfmsg->nfgen_family;
 761         int err = 0;
 762
 763         DEBUGP("entered %s\n", __FUNCTION__);
 764
 765         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 766                 u32 rlen;
 767
 768                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) ==
 769                                         IPCTNL_MSG_CT_GET_CTRZERO) {
 770 #ifdef CONFIG_NF_CT_ACCT
 771                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 772                                                 ctnetlink_dump_table_w,
 773                                                 ctnetlink_done)) != 0)
 774                                 return -EINVAL;
 775 #else
 776                         return -ENOTSUPP;
 777 #endif
 778                 } else {
 779                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 780                                                         ctnetlink_dump_table,
 781                                                         ctnetlink_done)) != 0)
 782                         return -EINVAL;
 783                 }
 784
 785                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 786                 if (rlen > skb->len)
 787                         rlen = skb->len;
 788                 skb_pull(skb, rlen);
 789                 return 0;
 790         }
 791
 792         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 793                 return -EINVAL;
 794
 795         if (cda[CTA_TUPLE_ORIG-1])
 796                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 797         else if (cda[CTA_TUPLE_REPLY-1])
 798                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 799         else
 800                 return -EINVAL;
 801
 802         if (err < 0)
 803                 return err;
 804
 805         h = nf_conntrack_find_get(&tuple, NULL);
 806         if (!h) {
 807                 DEBUGP("tuple not found in conntrack hash");
 808                 return -ENOENT;
 809         }
 810         DEBUGP("tuple found\n");
 811         ct = nf_ct_tuplehash_to_ctrack(h);
 812
 813         err = -ENOMEM;
 814         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 815         if (!skb2) {
 816                 nf_ct_put(ct);
 817                 return -ENOMEM;
 818         }
 819         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
 820
 821         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 822                                   IPCTNL_MSG_CT_NEW, 1, ct);
 823         nf_ct_put(ct);
 824         if (err <= 0)
 825                 goto free;
 826
 827         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 828         if (err < 0)
 829                 goto out;
 830
 831         DEBUGP("leaving\n");
 832         return 0;
 833
 834 free:
 835         kfree_skb(skb2);
 836 out:
 837         return err;
 838 }
 839
 840 static inline int
 841 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 842 {
 843         unsigned long d;
 844         unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1]));
 845         d = ct->status ^ status;
 846
 847         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 848                 /* unchangeable */
 849                 return -EINVAL;
 850
 851         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 852                 /* SEEN_REPLY bit can only be set */
 853                 return -EINVAL;
 854
 855
 856         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 857                 /* ASSURED bit can only be set */
 858                 return -EINVAL;
 859
 860         if (cda[CTA_NAT-1]) {
 861 #ifndef CONFIG_IP_NF_NAT_NEEDED
 862                 return -EINVAL;
 863 #else
 864                 unsigned int hooknum;
 865                 struct ip_nat_range range;
 866
 867                 if (ctnetlink_parse_nat(cda, ct, &range) < 0)
 868                         return -EINVAL;
 869
 870                 DEBUGP("NAT: %u.%u.%u.%u-%u.%u.%u.%u:%u-%u\n",
 871                        NIPQUAD(range.min_ip), NIPQUAD(range.max_ip),
 872                        htons(range.min.all), htons(range.max.all));
 873
 874                 /* This is tricky but it works. ip_nat_setup_info needs the
 875                  * hook number as parameter, so let's do the correct
 876                  * conversion and run away */
 877                 if (status & IPS_SRC_NAT_DONE)
 878                         hooknum = NF_IP_POST_ROUTING; /* IP_NAT_MANIP_SRC */
 879                 else if (status & IPS_DST_NAT_DONE)
 880                         hooknum = NF_IP_PRE_ROUTING;  /* IP_NAT_MANIP_DST */
 881                 else
 882                         return -EINVAL; /* Missing NAT flags */
 883
 884                 DEBUGP("NAT status: %lu\n",
 885                        status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK));
 886
 887                 if (ip_nat_initialized(ct, HOOK2MANIP(hooknum)))
 888                         return -EEXIST;
 889                 ip_nat_setup_info(ct, &range, hooknum);
 890
 891                 DEBUGP("NAT status after setup_info: %lu\n",
 892                        ct->status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK));
 893 #endif
 894         }
 895
 896         /* Be careful here, modifying NAT bits can screw up things,
 897          * so don't let users modify them directly if they don't pass
 898          * ip_nat_range. */
 899         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 900         return 0;
 901 }
 902
 903
 904 static inline int
 905 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 906 {
 907         struct nf_conntrack_helper *helper;
 908         struct nf_conn_help *help = nfct_help(ct);
 909         char *helpname;
 910         int err;
 911
 912         DEBUGP("entered %s\n", __FUNCTION__);
 913
 914         if (!help) {
 915                 /* FIXME: we need to reallocate and rehash */
 916                 return -EBUSY;
 917         }
 918
 919         /* don't change helper of sibling connections */
 920         if (ct->master)
 921                 return -EINVAL;
 922
 923         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 924         if (err < 0)
 925                 return err;
 926
 927         helper = __nf_conntrack_helper_find_byname(helpname);
 928         if (!helper) {
 929                 if (!strcmp(helpname, ""))
 930                         helper = NULL;
 931                 else
 932                         return -EINVAL;
 933         }
 934
 935         if (help->helper) {
 936                 if (!helper) {
 937                         /* we had a helper before ... */
 938                         nf_ct_remove_expectations(ct);
 939                         help->helper = NULL;
 940                 } else {
 941                         /* need to zero data of old helper */
 942                         memset(&help->help, 0, sizeof(help->help));
 943                 }
 944         }
 945
 946         help->helper = helper;
 947
 948         return 0;
 949 }
 950
 951 static inline int
 952 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 953 {
 954         u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 955
 956         if (!del_timer(&ct->timeout))
 957                 return -ETIME;
 958
 959         ct->timeout.expires = jiffies + timeout * HZ;
 960         add_timer(&ct->timeout);
 961
 962         return 0;
 963 }
 964
 965 static inline int
 966 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 967 {
 968         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 969         struct nf_conntrack_protocol *proto;
 970         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 971         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 972         int err = 0;
 973
 974         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 975
 976         proto = nf_ct_proto_find_get(l3num, npt);
 977
 978         if (proto->from_nfattr)
 979                 err = proto->from_nfattr(tb, ct);
 980         nf_ct_proto_put(proto);
 981
 982         return err;
 983 }
 984
 985 static int
 986 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
 987 {
 988         int err;
 989
 990         DEBUGP("entered %s\n", __FUNCTION__);
 991
 992         if (cda[CTA_HELP-1]) {
 993                 err = ctnetlink_change_helper(ct, cda);
 994                 if (err < 0)
 995                         return err;
 996         }
 997
 998         if (cda[CTA_TIMEOUT-1]) {
 999                 err = ctnetlink_change_timeout(ct, cda);
1000                 if (err < 0)
1001                         return err;
1002         }
1003
1004         if (cda[CTA_STATUS-1]) {
1005                 err = ctnetlink_change_status(ct, cda);
1006                 if (err < 0)
1007                         return err;
1008         }
1009
1010         if (cda[CTA_PROTOINFO-1]) {
1011                 err = ctnetlink_change_protoinfo(ct, cda);
1012                 if (err < 0)
1013                         return err;
1014         }
1015
1016 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
1017         if (cda[CTA_MARK-1])
1018                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1019 #endif
1020
1021         DEBUGP("all done\n");
1022         return 0;
1023 }
1024
1025 static int
1026 ctnetlink_create_conntrack(struct nfattr *cda[],
1027                            struct nf_conntrack_tuple *otuple,
1028                            struct nf_conntrack_tuple *rtuple)
1029 {
1030         struct nf_conn *ct;
1031         int err = -EINVAL;
1032
1033         DEBUGP("entered %s\n", __FUNCTION__);
1034
1035         ct = nf_conntrack_alloc(otuple, rtuple);
1036         if (ct == NULL || IS_ERR(ct))
1037                 return -ENOMEM;
1038
1039         if (!cda[CTA_TIMEOUT-1])
1040                 goto err;
1041         ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
1042
1043         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1044         ct->status |= IPS_CONFIRMED;
1045
1046         err = ctnetlink_change_status(ct, cda);
1047         if (err < 0)
1048                 goto err;
1049
1050         if (cda[CTA_PROTOINFO-1]) {
1051                 err = ctnetlink_change_protoinfo(ct, cda);
1052                 if (err < 0)
1053                         return err;
1054         }
1055
1056 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
1057         if (cda[CTA_MARK-1])
1058                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1059 #endif
1060
1061         add_timer(&ct->timeout);
1062         nf_conntrack_hash_insert(ct);
1063
1064         DEBUGP("conntrack with id %u inserted\n", ct->id);
1065         return 0;
1066
1067 err:
1068         nf_conntrack_free(ct);
1069         return err;
1070 }
1071
1072 static int
1073 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1074                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1075 {
1076         struct nf_conntrack_tuple otuple, rtuple;
1077         struct nf_conntrack_tuple_hash *h = NULL;
1078         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1079         u_int8_t u3 = nfmsg->nfgen_family;
1080         int err = 0;
1081
1082         DEBUGP("entered %s\n", __FUNCTION__);
1083
1084         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1085                 return -EINVAL;
1086
1087         if (cda[CTA_TUPLE_ORIG-1]) {
1088                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1089                 if (err < 0)
1090                         return err;
1091         }
1092
1093         if (cda[CTA_TUPLE_REPLY-1]) {
1094                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1095                 if (err < 0)
1096                         return err;
1097         }
1098
1099         write_lock_bh(&nf_conntrack_lock);
1100         if (cda[CTA_TUPLE_ORIG-1])
1101                 h = __nf_conntrack_find(&otuple, NULL);
1102         else if (cda[CTA_TUPLE_REPLY-1])
1103                 h = __nf_conntrack_find(&rtuple, NULL);
1104
1105         if (h == NULL) {
1106                 write_unlock_bh(&nf_conntrack_lock);
1107                 DEBUGP("no such conntrack, create new\n");
1108                 err = -ENOENT;
1109                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1110                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1111                 return err;
1112         }
1113         /* implicit 'else' */
1114
1115         /* we only allow nat config for new conntracks */
1116         if (cda[CTA_NAT-1]) {
1117                 err = -EINVAL;
1118                 goto out_unlock;
1119         }
1120
1121         /* We manipulate the conntrack inside the global conntrack table lock,
1122          * so there's no need to increase the refcount */
1123         DEBUGP("conntrack found\n");
1124         err = -EEXIST;
1125         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1126                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1127
1128 out_unlock:
1129         write_unlock_bh(&nf_conntrack_lock);
1130         return err;
1131 }
1132
1133 /***********************************************************************
1134  * EXPECT
1135  ***********************************************************************/
1136
1137 static inline int
1138 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1139                          const struct nf_conntrack_tuple *tuple,
1140                          enum ctattr_expect type)
1141 {
1142         struct nfattr *nest_parms = NFA_NEST(skb, type);
1143
1144         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1145                 goto nfattr_failure;
1146
1147         NFA_NEST_END(skb, nest_parms);
1148
1149         return 0;
1150
1151 nfattr_failure:
1152         return -1;
1153 }
1154
1155 static inline int
1156 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1157                           const struct nf_conntrack_expect *exp)
1158 {
1159         struct nf_conn *master = exp->master;
1160         u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1161         u_int32_t id = htonl(exp->id);
1162
1163         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1164                 goto nfattr_failure;
1165         if (ctnetlink_exp_dump_tuple(skb, &exp->mask, CTA_EXPECT_MASK) < 0)
1166                 goto nfattr_failure;
1167         if (ctnetlink_exp_dump_tuple(skb,
1168                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1169                                  CTA_EXPECT_MASTER) < 0)
1170                 goto nfattr_failure;
1171
1172         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1173         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1174
1175         return 0;
1176
1177 nfattr_failure:
1178         return -1;
1179 }
1180
1181 static int
1182 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1183                     int event,
1184                     int nowait,
1185                     const struct nf_conntrack_expect *exp)
1186 {
1187         struct nlmsghdr *nlh;
1188         struct nfgenmsg *nfmsg;
1189         unsigned char *b;
1190
1191         b = skb->tail;
1192
1193         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1194         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1195         nfmsg  = NLMSG_DATA(nlh);
1196
1197         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1198         nfmsg->nfgen_family = exp->tuple.src.l3num;
1199         nfmsg->version      = NFNETLINK_V0;
1200         nfmsg->res_id       = 0;
1201
1202         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1203                 goto nfattr_failure;
1204
1205         nlh->nlmsg_len = skb->tail - b;
1206         return skb->len;
1207
1208 nlmsg_failure:
1209 nfattr_failure:
1210         skb_trim(skb, b - skb->data);
1211         return -1;
1212 }
1213
1214 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1215 static int ctnetlink_expect_event(struct notifier_block *this,
1216                                   unsigned long events, void *ptr)
1217 {
1218         struct nlmsghdr *nlh;
1219         struct nfgenmsg *nfmsg;
1220         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1221         struct sk_buff *skb;
1222         unsigned int type;
1223         unsigned char *b;
1224         int flags = 0;
1225
1226         if (events & IPEXP_NEW) {
1227                 type = IPCTNL_MSG_EXP_NEW;
1228                 flags = NLM_F_CREATE|NLM_F_EXCL;
1229         } else
1230                 return NOTIFY_DONE;
1231
1232         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1233         if (!skb)
1234                 return NOTIFY_DONE;
1235
1236         b = skb->tail;
1237
1238         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1239         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1240         nfmsg = NLMSG_DATA(nlh);
1241
1242         nlh->nlmsg_flags    = flags;
1243         nfmsg->nfgen_family = exp->tuple.src.l3num;
1244         nfmsg->version      = NFNETLINK_V0;
1245         nfmsg->res_id       = 0;
1246
1247         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1248                 goto nfattr_failure;
1249
1250         nlh->nlmsg_len = skb->tail - b;
1251         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1252         return NOTIFY_DONE;
1253
1254 nlmsg_failure:
1255 nfattr_failure:
1256         kfree_skb(skb);
1257         return NOTIFY_DONE;
1258 }
1259 #endif
1260
1261 static int
1262 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1263 {
1264         struct nf_conntrack_expect *exp = NULL;
1265         struct list_head *i;
1266         u_int32_t *id = (u_int32_t *) &cb->args[0];
1267         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1268         u_int8_t l3proto = nfmsg->nfgen_family;
1269
1270         DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id);
1271
1272         read_lock_bh(&nf_conntrack_lock);
1273         list_for_each_prev(i, &nf_conntrack_expect_list) {
1274                 exp = (struct nf_conntrack_expect *) i;
1275                 if (l3proto && exp->tuple.src.l3num != l3proto)
1276                         continue;
1277                 if (exp->id <= *id)
1278                         continue;
1279                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1280                                             cb->nlh->nlmsg_seq,
1281                                             IPCTNL_MSG_EXP_NEW,
1282                                             1, exp) < 0)
1283                         goto out;
1284                 *id = exp->id;
1285         }
1286 out:
1287         read_unlock_bh(&nf_conntrack_lock);
1288
1289         DEBUGP("leaving, last id=%llu\n", *id);
1290
1291         return skb->len;
1292 }
1293
1294 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1295         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1296         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1297 };
1298
1299 static int
1300 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1301                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1302 {
1303         struct nf_conntrack_tuple tuple;
1304         struct nf_conntrack_expect *exp;
1305         struct sk_buff *skb2;
1306         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1307         u_int8_t u3 = nfmsg->nfgen_family;
1308         int err = 0;
1309
1310         DEBUGP("entered %s\n", __FUNCTION__);
1311
1312         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1313                 return -EINVAL;
1314
1315         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1316                 u32 rlen;
1317
1318                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1319                                                 ctnetlink_exp_dump_table,
1320                                                 ctnetlink_done)) != 0)
1321                         return -EINVAL;
1322                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1323                 if (rlen > skb->len)
1324                         rlen = skb->len;
1325                 skb_pull(skb, rlen);
1326                 return 0;
1327         }
1328
1329         if (cda[CTA_EXPECT_MASTER-1])
1330                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1331         else
1332                 return -EINVAL;
1333
1334         if (err < 0)
1335                 return err;
1336
1337         exp = nf_conntrack_expect_find(&tuple);
1338         if (!exp)
1339                 return -ENOENT;
1340
1341         if (cda[CTA_EXPECT_ID-1]) {
1342                 u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1343                 if (exp->id != ntohl(id)) {
1344                         nf_conntrack_expect_put(exp);
1345                         return -ENOENT;
1346                 }
1347         }
1348
1349         err = -ENOMEM;
1350         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1351         if (!skb2)
1352                 goto out;
1353         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
1354
1355         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1356                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1357                                       1, exp);
1358         if (err <= 0)
1359                 goto free;
1360
1361         nf_conntrack_expect_put(exp);
1362
1363         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1364
1365 free:
1366         kfree_skb(skb2);
1367 out:
1368         nf_conntrack_expect_put(exp);
1369         return err;
1370 }
1371
1372 static int
1373 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1374                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1375 {
1376         struct nf_conntrack_expect *exp, *tmp;
1377         struct nf_conntrack_tuple tuple;
1378         struct nf_conntrack_helper *h;
1379         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1380         u_int8_t u3 = nfmsg->nfgen_family;
1381         int err;
1382
1383         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1384                 return -EINVAL;
1385
1386         if (cda[CTA_EXPECT_TUPLE-1]) {
1387                 /* delete a single expect by tuple */
1388                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1389                 if (err < 0)
1390                         return err;
1391
1392                 /* bump usage count to 2 */
1393                 exp = nf_conntrack_expect_find(&tuple);
1394                 if (!exp)
1395                         return -ENOENT;
1396
1397                 if (cda[CTA_EXPECT_ID-1]) {
1398                         u_int32_t id =
1399                                 *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1400                         if (exp->id != ntohl(id)) {
1401                                 nf_conntrack_expect_put(exp);
1402                                 return -ENOENT;
1403                         }
1404                 }
1405
1406                 /* after list removal, usage count == 1 */
1407                 nf_conntrack_unexpect_related(exp);
1408                 /* have to put what we 'get' above.
1409                  * after this line usage count == 0 */
1410                 nf_conntrack_expect_put(exp);
1411         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1412                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1413
1414                 /* delete all expectations for this helper */
1415                 write_lock_bh(&nf_conntrack_lock);
1416                 h = __nf_conntrack_helper_find_byname(name);
1417                 if (!h) {
1418                         write_unlock_bh(&nf_conntrack_lock);
1419                         return -EINVAL;
1420                 }
1421                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1422                                          list) {
1423                         struct nf_conn_help *m_help = nfct_help(exp->master);
1424                         if (m_help->helper == h
1425                             && del_timer(&exp->timeout)) {
1426                                 nf_ct_unlink_expect(exp);
1427                                 nf_conntrack_expect_put(exp);
1428                         }
1429                 }
1430                 write_unlock_bh(&nf_conntrack_lock);
1431         } else {
1432                 /* This basically means we have to flush everything*/
1433                 write_lock_bh(&nf_conntrack_lock);
1434                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1435                                          list) {
1436                         if (del_timer(&exp->timeout)) {
1437                                 nf_ct_unlink_expect(exp);
1438                                 nf_conntrack_expect_put(exp);
1439                         }
1440                 }
1441                 write_unlock_bh(&nf_conntrack_lock);
1442         }
1443
1444         return 0;
1445 }
1446 static int
1447 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1448 {
1449         return -EOPNOTSUPP;
1450 }
1451
1452 static int
1453 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1454 {
1455         struct nf_conntrack_tuple tuple, mask, master_tuple;
1456         struct nf_conntrack_tuple_hash *h = NULL;
1457         struct nf_conntrack_expect *exp;
1458         struct nf_conn *ct;
1459         struct nf_conn_help *help;
1460         int err = 0;
1461
1462         DEBUGP("entered %s\n", __FUNCTION__);
1463
1464         /* caller guarantees that those three CTA_EXPECT_* exist */
1465         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1466         if (err < 0)
1467                 return err;
1468         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1469         if (err < 0)
1470                 return err;
1471         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1472         if (err < 0)
1473                 return err;
1474
1475         /* Look for master conntrack of this expectation */
1476         h = nf_conntrack_find_get(&master_tuple, NULL);
1477         if (!h)
1478                 return -ENOENT;
1479         ct = nf_ct_tuplehash_to_ctrack(h);
1480         help = nfct_help(ct);
1481
1482         if (!help || !help->helper) {
1483                 /* such conntrack hasn't got any helper, abort */
1484                 err = -EINVAL;
1485                 goto out;
1486         }
1487
1488         exp = nf_conntrack_expect_alloc(ct);
1489         if (!exp) {
1490                 err = -ENOMEM;
1491                 goto out;
1492         }
1493
1494         exp->expectfn = NULL;
1495         exp->flags = 0;
1496         exp->master = ct;
1497         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1498         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1499
1500         err = nf_conntrack_expect_related(exp);
1501         nf_conntrack_expect_put(exp);
1502
1503 out:
1504         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1505         return err;
1506 }
1507
1508 static int
1509 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1510                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1511 {
1512         struct nf_conntrack_tuple tuple;
1513         struct nf_conntrack_expect *exp;
1514         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1515         u_int8_t u3 = nfmsg->nfgen_family;
1516         int err = 0;
1517
1518         DEBUGP("entered %s\n", __FUNCTION__);
1519
1520         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1521                 return -EINVAL;
1522
1523         if (!cda[CTA_EXPECT_TUPLE-1]
1524             || !cda[CTA_EXPECT_MASK-1]
1525             || !cda[CTA_EXPECT_MASTER-1])
1526                 return -EINVAL;
1527
1528         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1529         if (err < 0)
1530                 return err;
1531
1532         write_lock_bh(&nf_conntrack_lock);
1533         exp = __nf_conntrack_expect_find(&tuple);
1534
1535         if (!exp) {
1536                 write_unlock_bh(&nf_conntrack_lock);
1537                 err = -ENOENT;
1538                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1539                         err = ctnetlink_create_expect(cda, u3);
1540                 return err;
1541         }
1542
1543         err = -EEXIST;
1544         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1545                 err = ctnetlink_change_expect(exp, cda);
1546         write_unlock_bh(&nf_conntrack_lock);
1547
1548         DEBUGP("leaving\n");
1549
1550         return err;
1551 }
1552
1553 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1554 static struct notifier_block ctnl_notifier = {
1555         .notifier_call  = ctnetlink_conntrack_event,
1556 };
1557
1558 static struct notifier_block ctnl_notifier_exp = {
1559         .notifier_call  = ctnetlink_expect_event,
1560 };
1561 #endif
1562
1563 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1564         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1565                                             .attr_count = CTA_MAX, },
1566         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1567                                             .attr_count = CTA_MAX, },
1568         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1569                                             .attr_count = CTA_MAX, },
1570         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1571                                             .attr_count = CTA_MAX, },
1572 };
1573
1574 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1575         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1576                                             .attr_count = CTA_EXPECT_MAX, },
1577         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1578                                             .attr_count = CTA_EXPECT_MAX, },
1579         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1580                                             .attr_count = CTA_EXPECT_MAX, },
1581 };
1582
1583 static struct nfnetlink_subsystem ctnl_subsys = {
1584         .name                           = "conntrack",
1585         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1586         .cb_count                       = IPCTNL_MSG_MAX,
1587         .cb                             = ctnl_cb,
1588 };
1589
1590 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1591         .name                           = "conntrack_expect",
1592         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1593         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1594         .cb                             = ctnl_exp_cb,
1595 };
1596
1597 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1598 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1599
1600 static int __init ctnetlink_init(void)
1601 {
1602         int ret;
1603
1604         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1605         ret = nfnetlink_subsys_register(&ctnl_subsys);
1606         if (ret < 0) {
1607                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1608                 goto err_out;
1609         }
1610
1611         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1612         if (ret < 0) {
1613                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1614                 goto err_unreg_subsys;
1615         }
1616
1617 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1618         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1619         if (ret < 0) {
1620                 printk("ctnetlink_init: cannot register notifier.\n");
1621                 goto err_unreg_exp_subsys;
1622         }
1623
1624         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1625         if (ret < 0) {
1626                 printk("ctnetlink_init: cannot expect register notifier.\n");
1627                 goto err_unreg_notifier;
1628         }
1629 #endif
1630
1631         return 0;
1632
1633 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1634 err_unreg_notifier:
1635         nf_conntrack_unregister_notifier(&ctnl_notifier);
1636 err_unreg_exp_subsys:
1637         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1638 #endif
1639 err_unreg_subsys:
1640         nfnetlink_subsys_unregister(&ctnl_subsys);
1641 err_out:
1642         return ret;
1643 }
1644
1645 static void __exit ctnetlink_exit(void)
1646 {
1647         printk("ctnetlink: unregistering from nfnetlink.\n");
1648
1649 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1650         nf_conntrack_unregister_notifier(&ctnl_notifier_exp);
1651         nf_conntrack_unregister_notifier(&ctnl_notifier);
1652 #endif
1653
1654         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1655         nfnetlink_subsys_unregister(&ctnl_subsys);
1656         return;
1657 }
1658
1659 module_init(ctnetlink_init);
1660 module_exit(ctnetlink_exit);