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) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net>
   8  *
   9  * I've reworked this stuff to use attributes instead of conntrack
  10  * structures. 5.44 am. I need more tea. --pablo 05/07/11.
  11  *
  12  * Initial connection tracking via netlink development funded and
  13  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
  14  *
  15  * Further development of this code funded by Astaro AG (http://www.astaro.com)
  16  *
  17  * This software may be used and distributed according to the terms
  18  * of the GNU General Public License, incorporated herein by reference.
  19  *
  20  * 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/interrupt.h>
  33 #include <linux/notifier.h>
  34
  35 #include <linux/netfilter.h>
  36 #include <net/netfilter/nf_conntrack.h>
  37 #include <net/netfilter/nf_conntrack_core.h>
  38 #include <net/netfilter/nf_conntrack_helper.h>
  39 #include <net/netfilter/nf_conntrack_l3proto.h>
  40 #include <net/netfilter/nf_conntrack_protocol.h>
  41 #include <linux/netfilter_ipv4/ip_nat_protocol.h>
  42
  43 #include <linux/netfilter/nfnetlink.h>
  44 #include <linux/netfilter/nfnetlink_conntrack.h>
  45
  46 MODULE_LICENSE("GPL");
  47
  48 static char __initdata version[] = "0.93";
  49
  50 #if 0
  51 #define DEBUGP printk
  52 #else
  53 #define DEBUGP(format, args...)
  54 #endif
  55
  56
  57 static inline int
  58 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  59                             const struct nf_conntrack_tuple *tuple,
  60                             struct nf_conntrack_protocol *proto)
  61 {
  62         int ret = 0;
  63         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  64
  65         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  66
  67         if (likely(proto->tuple_to_nfattr))
  68                 ret = proto->tuple_to_nfattr(skb, tuple);
  69
  70         NFA_NEST_END(skb, nest_parms);
  71
  72         return ret;
  73
  74 nfattr_failure:
  75         return -1;
  76 }
  77
  78 static inline int
  79 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  80                          const struct nf_conntrack_tuple *tuple,
  81                          struct nf_conntrack_l3proto *l3proto)
  82 {
  83         int ret = 0;
  84         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  85
  86         if (likely(l3proto->tuple_to_nfattr))
  87                 ret = l3proto->tuple_to_nfattr(skb, tuple);
  88
  89         NFA_NEST_END(skb, nest_parms);
  90
  91         return ret;
  92
  93 nfattr_failure:
  94         return -1;
  95 }
  96
  97 static inline int
  98 ctnetlink_dump_tuples(struct sk_buff *skb,
  99                       const struct nf_conntrack_tuple *tuple)
 100 {
 101         int ret;
 102         struct nf_conntrack_l3proto *l3proto;
 103         struct nf_conntrack_protocol *proto;
 104
 105         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 106         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 107         nf_ct_l3proto_put(l3proto);
 108
 109         if (unlikely(ret < 0))
 110                 return ret;
 111
 112         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 113         ret = ctnetlink_dump_tuples_proto(skb, tuple, proto);
 114         nf_ct_proto_put(proto);
 115
 116         return ret;
 117 }
 118
 119 static inline int
 120 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 121 {
 122         u_int32_t status = htonl((u_int32_t) ct->status);
 123         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 124         return 0;
 125
 126 nfattr_failure:
 127         return -1;
 128 }
 129
 130 static inline int
 131 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 132 {
 133         long timeout_l = ct->timeout.expires - jiffies;
 134         u_int32_t timeout;
 135
 136         if (timeout_l < 0)
 137                 timeout = 0;
 138         else
 139                 timeout = htonl(timeout_l / HZ);
 140
 141         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 142         return 0;
 143
 144 nfattr_failure:
 145         return -1;
 146 }
 147
 148 static inline int
 149 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 150 {
 151         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);
 152         struct nfattr *nest_proto;
 153         int ret;
 154
 155         if (!proto->to_nfattr) {
 156                 nf_ct_proto_put(proto);
 157                 return 0;
 158         }
 159
 160         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 161
 162         ret = proto->to_nfattr(skb, nest_proto, ct);
 163
 164         nf_ct_proto_put(proto);
 165
 166         NFA_NEST_END(skb, nest_proto);
 167
 168         return ret;
 169
 170 nfattr_failure:
 171         return -1;
 172 }
 173
 174 static inline int
 175 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 176 {
 177         struct nfattr *nest_helper;
 178         const struct nf_conn_help *help = nfct_help(ct);
 179
 180         if (!help || !help->helper)
 181                 return 0;
 182
 183         nest_helper = NFA_NEST(skb, CTA_HELP);
 184         NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
 185
 186         if (help->helper->to_nfattr)
 187                 help->helper->to_nfattr(skb, ct);
 188
 189         NFA_NEST_END(skb, nest_helper);
 190
 191         return 0;
 192
 193 nfattr_failure:
 194         return -1;
 195 }
 196
 197 #ifdef CONFIG_NF_CT_ACCT
 198 static inline int
 199 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 200                         enum ip_conntrack_dir dir)
 201 {
 202         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 203         struct nfattr *nest_count = NFA_NEST(skb, type);
 204         u_int32_t tmp;
 205
 206         tmp = htonl(ct->counters[dir].packets);
 207         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 208
 209         tmp = htonl(ct->counters[dir].bytes);
 210         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 211
 212         NFA_NEST_END(skb, nest_count);
 213
 214         return 0;
 215
 216 nfattr_failure:
 217         return -1;
 218 }
 219 #else
 220 #define ctnetlink_dump_counters(a, b, c) (0)
 221 #endif
 222
 223 #ifdef CONFIG_NF_CONNTRACK_MARK
 224 static inline int
 225 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 226 {
 227         u_int32_t mark = htonl(ct->mark);
 228
 229         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 230         return 0;
 231
 232 nfattr_failure:
 233         return -1;
 234 }
 235 #else
 236 #define ctnetlink_dump_mark(a, b) (0)
 237 #endif
 238
 239 static inline int
 240 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 241 {
 242         u_int32_t id = htonl(ct->id);
 243         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 244         return 0;
 245
 246 nfattr_failure:
 247         return -1;
 248 }
 249
 250 static inline int
 251 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 252 {
 253         u_int32_t use = htonl(atomic_read(&ct->ct_general.use));
 254
 255         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 256         return 0;
 257
 258 nfattr_failure:
 259         return -1;
 260 }
 261
 262 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 263
 264 static int
 265 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 266                     int event, int nowait,
 267                     const struct nf_conn *ct)
 268 {
 269         struct nlmsghdr *nlh;
 270         struct nfgenmsg *nfmsg;
 271         struct nfattr *nest_parms;
 272         unsigned char *b;
 273
 274         b = skb->tail;
 275
 276         event |= NFNL_SUBSYS_CTNETLINK << 8;
 277         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 278         nfmsg  = NLMSG_DATA(nlh);
 279
 280         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 281         nfmsg->nfgen_family =
 282                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 283         nfmsg->version      = NFNETLINK_V0;
 284         nfmsg->res_id       = 0;
 285
 286         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 287         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 288                 goto nfattr_failure;
 289         NFA_NEST_END(skb, nest_parms);
 290
 291         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 292         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 293                 goto nfattr_failure;
 294         NFA_NEST_END(skb, nest_parms);
 295
 296         if (ctnetlink_dump_status(skb, ct) < 0 ||
 297             ctnetlink_dump_timeout(skb, ct) < 0 ||
 298             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 299             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 300             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 301             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 302             ctnetlink_dump_mark(skb, ct) < 0 ||
 303             ctnetlink_dump_id(skb, ct) < 0 ||
 304             ctnetlink_dump_use(skb, ct) < 0)
 305                 goto nfattr_failure;
 306
 307         nlh->nlmsg_len = skb->tail - b;
 308         return skb->len;
 309
 310 nlmsg_failure:
 311 nfattr_failure:
 312         skb_trim(skb, b - skb->data);
 313         return -1;
 314 }
 315
 316 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 317 static int ctnetlink_conntrack_event(struct notifier_block *this,
 318                                      unsigned long events, void *ptr)
 319 {
 320         struct nlmsghdr *nlh;
 321         struct nfgenmsg *nfmsg;
 322         struct nfattr *nest_parms;
 323         struct nf_conn *ct = (struct nf_conn *)ptr;
 324         struct sk_buff *skb;
 325         unsigned int type;
 326         unsigned char *b;
 327         unsigned int flags = 0, group;
 328
 329         /* ignore our fake conntrack entry */
 330         if (ct == &nf_conntrack_untracked)
 331                 return NOTIFY_DONE;
 332
 333         if (events & IPCT_DESTROY) {
 334                 type = IPCTNL_MSG_CT_DELETE;
 335                 group = NFNLGRP_CONNTRACK_DESTROY;
 336         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 337                 type = IPCTNL_MSG_CT_NEW;
 338                 flags = NLM_F_CREATE|NLM_F_EXCL;
 339                 /* dump everything */
 340                 events = ~0UL;
 341                 group = NFNLGRP_CONNTRACK_NEW;
 342         } else  if (events & (IPCT_STATUS |
 343                       IPCT_PROTOINFO |
 344                       IPCT_HELPER |
 345                       IPCT_HELPINFO |
 346                       IPCT_NATINFO)) {
 347                 type = IPCTNL_MSG_CT_NEW;
 348                 group = NFNLGRP_CONNTRACK_UPDATE;
 349         } else
 350                 return NOTIFY_DONE;
 351
 352         if (!nfnetlink_has_listeners(group))
 353                 return NOTIFY_DONE;
 354
 355         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 356         if (!skb)
 357                 return NOTIFY_DONE;
 358
 359         b = skb->tail;
 360
 361         type |= NFNL_SUBSYS_CTNETLINK << 8;
 362         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 363         nfmsg = NLMSG_DATA(nlh);
 364
 365         nlh->nlmsg_flags    = flags;
 366         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 367         nfmsg->version  = NFNETLINK_V0;
 368         nfmsg->res_id   = 0;
 369
 370         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 371         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 372                 goto nfattr_failure;
 373         NFA_NEST_END(skb, nest_parms);
 374
 375         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 376         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 377                 goto nfattr_failure;
 378         NFA_NEST_END(skb, nest_parms);
 379
 380         /* NAT stuff is now a status flag */
 381         if ((events & IPCT_STATUS || events & IPCT_NATINFO)
 382             && ctnetlink_dump_status(skb, ct) < 0)
 383                 goto nfattr_failure;
 384         if (events & IPCT_REFRESH
 385             && ctnetlink_dump_timeout(skb, ct) < 0)
 386                 goto nfattr_failure;
 387         if (events & IPCT_PROTOINFO
 388             && ctnetlink_dump_protoinfo(skb, ct) < 0)
 389                 goto nfattr_failure;
 390         if (events & IPCT_HELPINFO
 391             && ctnetlink_dump_helpinfo(skb, ct) < 0)
 392                 goto nfattr_failure;
 393
 394         if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 395             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 396                 goto nfattr_failure;
 397
 398         nlh->nlmsg_len = skb->tail - b;
 399         nfnetlink_send(skb, 0, group, 0);
 400         return NOTIFY_DONE;
 401
 402 nlmsg_failure:
 403 nfattr_failure:
 404         kfree_skb(skb);
 405         return NOTIFY_DONE;
 406 }
 407 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 408
 409 static int ctnetlink_done(struct netlink_callback *cb)
 410 {
 411         if (cb->args[1])
 412                 nf_ct_put((struct nf_conn *)cb->args[1]);
 413         DEBUGP("entered %s\n", __FUNCTION__);
 414         return 0;
 415 }
 416
 417 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 418
 419 static int
 420 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 421 {
 422         struct nf_conn *ct, *last;
 423         struct nf_conntrack_tuple_hash *h;
 424         struct list_head *i;
 425         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 426         u_int8_t l3proto = nfmsg->nfgen_family;
 427
 428         DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__,
 429                         cb->args[0], *id);
 430
 431         read_lock_bh(&nf_conntrack_lock);
 432         last = (struct nf_conn *)cb->args[1];
 433         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
 434 restart:
 435                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 436                         h = (struct nf_conntrack_tuple_hash *) i;
 437                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 438                                 continue;
 439                         ct = nf_ct_tuplehash_to_ctrack(h);
 440                         /* Dump entries of a given L3 protocol number.
 441                          * If it is not specified, ie. l3proto == 0,
 442                          * then dump everything. */
 443                         if (l3proto && L3PROTO(ct) != l3proto)
 444                                 continue;
 445                         if (cb->args[1]) {
 446                                 if (ct != last)
 447                                         continue;
 448                                 cb->args[1] = 0;
 449                         }
 450                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 451                                                 cb->nlh->nlmsg_seq,
 452                                                 IPCTNL_MSG_CT_NEW,
 453                                                 1, ct) < 0) {
 454                                 nf_conntrack_get(&ct->ct_general);
 455                                 cb->args[1] = (unsigned long)ct;
 456                                 goto out;
 457                         }
 458                 }
 459                 if (cb->args[1]) {
 460                         cb->args[1] = 0;
 461                         goto restart;
 462                 }
 463         }
 464 out:
 465         read_unlock_bh(&nf_conntrack_lock);
 466         if (last)
 467                 nf_ct_put(last);
 468
 469         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 470         return skb->len;
 471 }
 472
 473 #ifdef CONFIG_NF_CT_ACCT
 474 static int
 475 ctnetlink_dump_table_w(struct sk_buff *skb, struct netlink_callback *cb)
 476 {
 477         struct nf_conn *ct = NULL;
 478         struct nf_conntrack_tuple_hash *h;
 479         struct list_head *i;
 480         u_int32_t *id = (u_int32_t *) &cb->args[1];
 481         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 482         u_int8_t l3proto = nfmsg->nfgen_family;
 483
 484         DEBUGP("entered %s, last bucket=%u id=%u\n", __FUNCTION__,
 485                         cb->args[0], *id);
 486
 487         write_lock_bh(&nf_conntrack_lock);
 488         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 489                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 490                         h = (struct nf_conntrack_tuple_hash *) i;
 491                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 492                                 continue;
 493                         ct = nf_ct_tuplehash_to_ctrack(h);
 494                         if (l3proto && L3PROTO(ct) != l3proto)
 495                                 continue;
 496                         if (ct->id <= *id)
 497                                 continue;
 498                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 499                                                 cb->nlh->nlmsg_seq,
 500                                                 IPCTNL_MSG_CT_NEW,
 501                                                 1, ct) < 0)
 502                                 goto out;
 503                         *id = ct->id;
 504
 505                         memset(&ct->counters, 0, sizeof(ct->counters));
 506                 }
 507         }
 508 out:
 509         write_unlock_bh(&nf_conntrack_lock);
 510
 511         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 512
 513         return skb->len;
 514 }
 515 #endif
 516
 517 static inline int
 518 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 519 {
 520         struct nfattr *tb[CTA_IP_MAX];
 521         struct nf_conntrack_l3proto *l3proto;
 522         int ret = 0;
 523
 524         DEBUGP("entered %s\n", __FUNCTION__);
 525
 526         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 527
 528         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 529
 530         if (likely(l3proto->nfattr_to_tuple))
 531                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 532
 533         nf_ct_l3proto_put(l3proto);
 534
 535         DEBUGP("leaving\n");
 536
 537         return ret;
 538 }
 539
 540 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 541         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 542 };
 543
 544 static inline int
 545 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 546                             struct nf_conntrack_tuple *tuple)
 547 {
 548         struct nfattr *tb[CTA_PROTO_MAX];
 549         struct nf_conntrack_protocol *proto;
 550         int ret = 0;
 551
 552         DEBUGP("entered %s\n", __FUNCTION__);
 553
 554         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 555
 556         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 557                 return -EINVAL;
 558
 559         if (!tb[CTA_PROTO_NUM-1])
 560                 return -EINVAL;
 561         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 562
 563         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 564
 565         if (likely(proto->nfattr_to_tuple))
 566                 ret = proto->nfattr_to_tuple(tb, tuple);
 567
 568         nf_ct_proto_put(proto);
 569
 570         return ret;
 571 }
 572
 573 static inline int
 574 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 575                       enum ctattr_tuple type, u_int8_t l3num)
 576 {
 577         struct nfattr *tb[CTA_TUPLE_MAX];
 578         int err;
 579
 580         DEBUGP("entered %s\n", __FUNCTION__);
 581
 582         memset(tuple, 0, sizeof(*tuple));
 583
 584         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 585
 586         if (!tb[CTA_TUPLE_IP-1])
 587                 return -EINVAL;
 588
 589         tuple->src.l3num = l3num;
 590
 591         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 592         if (err < 0)
 593                 return err;
 594
 595         if (!tb[CTA_TUPLE_PROTO-1])
 596                 return -EINVAL;
 597
 598         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 599         if (err < 0)
 600                 return err;
 601
 602         /* orig and expect tuples get DIR_ORIGINAL */
 603         if (type == CTA_TUPLE_REPLY)
 604                 tuple->dst.dir = IP_CT_DIR_REPLY;
 605         else
 606                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 607
 608         NF_CT_DUMP_TUPLE(tuple);
 609
 610         DEBUGP("leaving\n");
 611
 612         return 0;
 613 }
 614
 615 #ifdef CONFIG_IP_NF_NAT_NEEDED
 616 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 617         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 618         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 619 };
 620
 621 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 622                                      const struct nf_conn *ct,
 623                                      struct ip_nat_range *range)
 624 {
 625         struct nfattr *tb[CTA_PROTONAT_MAX];
 626         struct ip_nat_protocol *npt;
 627
 628         DEBUGP("entered %s\n", __FUNCTION__);
 629
 630         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 631
 632         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 633                 return -EINVAL;
 634
 635         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 636
 637         if (!npt->nfattr_to_range) {
 638                 ip_nat_proto_put(npt);
 639                 return 0;
 640         }
 641
 642         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 643         if (npt->nfattr_to_range(tb, range) > 0)
 644                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 645
 646         ip_nat_proto_put(npt);
 647
 648         DEBUGP("leaving\n");
 649         return 0;
 650 }
 651
 652 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 653         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 654         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 655 };
 656
 657 static inline int
 658 ctnetlink_parse_nat(struct nfattr *nat,
 659                     const struct nf_conn *ct, struct ip_nat_range *range)
 660 {
 661         struct nfattr *tb[CTA_NAT_MAX];
 662         int err;
 663
 664         DEBUGP("entered %s\n", __FUNCTION__);
 665
 666         memset(range, 0, sizeof(*range));
 667
 668         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 669
 670         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 671                 return -EINVAL;
 672
 673         if (tb[CTA_NAT_MINIP-1])
 674                 range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 675
 676         if (!tb[CTA_NAT_MAXIP-1])
 677                 range->max_ip = range->min_ip;
 678         else
 679                 range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 680
 681         if (range->min_ip)
 682                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 683
 684         if (!tb[CTA_NAT_PROTO-1])
 685                 return 0;
 686
 687         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 688         if (err < 0)
 689                 return err;
 690
 691         DEBUGP("leaving\n");
 692         return 0;
 693 }
 694 #endif
 695
 696 static inline int
 697 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 698 {
 699         struct nfattr *tb[CTA_HELP_MAX];
 700
 701         DEBUGP("entered %s\n", __FUNCTION__);
 702
 703         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 704
 705         if (!tb[CTA_HELP_NAME-1])
 706                 return -EINVAL;
 707
 708         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 709
 710         return 0;
 711 }
 712
 713 static const size_t cta_min[CTA_MAX] = {
 714         [CTA_STATUS-1]          = sizeof(u_int32_t),
 715         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 716         [CTA_MARK-1]            = sizeof(u_int32_t),
 717         [CTA_USE-1]             = sizeof(u_int32_t),
 718         [CTA_ID-1]              = sizeof(u_int32_t)
 719 };
 720
 721 static int
 722 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 723                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 724 {
 725         struct nf_conntrack_tuple_hash *h;
 726         struct nf_conntrack_tuple tuple;
 727         struct nf_conn *ct;
 728         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 729         u_int8_t u3 = nfmsg->nfgen_family;
 730         int err = 0;
 731
 732         DEBUGP("entered %s\n", __FUNCTION__);
 733
 734         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 735                 return -EINVAL;
 736
 737         if (cda[CTA_TUPLE_ORIG-1])
 738                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 739         else if (cda[CTA_TUPLE_REPLY-1])
 740                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 741         else {
 742                 /* Flush the whole table */
 743                 nf_conntrack_flush();
 744                 return 0;
 745         }
 746
 747         if (err < 0)
 748                 return err;
 749
 750         h = nf_conntrack_find_get(&tuple, NULL);
 751         if (!h) {
 752                 DEBUGP("tuple not found in conntrack hash\n");
 753                 return -ENOENT;
 754         }
 755
 756         ct = nf_ct_tuplehash_to_ctrack(h);
 757
 758         if (cda[CTA_ID-1]) {
 759                 u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1]));
 760                 if (ct->id != id) {
 761                         nf_ct_put(ct);
 762                         return -ENOENT;
 763                 }
 764         }
 765         if (del_timer(&ct->timeout))
 766                 ct->timeout.function((unsigned long)ct);
 767
 768         nf_ct_put(ct);
 769         DEBUGP("leaving\n");
 770
 771         return 0;
 772 }
 773
 774 static int
 775 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 776                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 777 {
 778         struct nf_conntrack_tuple_hash *h;
 779         struct nf_conntrack_tuple tuple;
 780         struct nf_conn *ct;
 781         struct sk_buff *skb2 = NULL;
 782         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 783         u_int8_t u3 = nfmsg->nfgen_family;
 784         int err = 0;
 785
 786         DEBUGP("entered %s\n", __FUNCTION__);
 787
 788         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 789                 u32 rlen;
 790
 791                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) ==
 792                                         IPCTNL_MSG_CT_GET_CTRZERO) {
 793 #ifdef CONFIG_NF_CT_ACCT
 794                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 795                                                 ctnetlink_dump_table_w,
 796                                                 ctnetlink_done)) != 0)
 797                                 return -EINVAL;
 798 #else
 799                         return -ENOTSUPP;
 800 #endif
 801                 } else {
 802                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 803                                                         ctnetlink_dump_table,
 804                                                         ctnetlink_done)) != 0)
 805                         return -EINVAL;
 806                 }
 807
 808                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 809                 if (rlen > skb->len)
 810                         rlen = skb->len;
 811                 skb_pull(skb, rlen);
 812                 return 0;
 813         }
 814
 815         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 816                 return -EINVAL;
 817
 818         if (cda[CTA_TUPLE_ORIG-1])
 819                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 820         else if (cda[CTA_TUPLE_REPLY-1])
 821                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 822         else
 823                 return -EINVAL;
 824
 825         if (err < 0)
 826                 return err;
 827
 828         h = nf_conntrack_find_get(&tuple, NULL);
 829         if (!h) {
 830                 DEBUGP("tuple not found in conntrack hash");
 831                 return -ENOENT;
 832         }
 833         DEBUGP("tuple found\n");
 834         ct = nf_ct_tuplehash_to_ctrack(h);
 835
 836         err = -ENOMEM;
 837         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 838         if (!skb2) {
 839                 nf_ct_put(ct);
 840                 return -ENOMEM;
 841         }
 842         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
 843
 844         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 845                                   IPCTNL_MSG_CT_NEW, 1, ct);
 846         nf_ct_put(ct);
 847         if (err <= 0)
 848                 goto free;
 849
 850         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 851         if (err < 0)
 852                 goto out;
 853
 854         DEBUGP("leaving\n");
 855         return 0;
 856
 857 free:
 858         kfree_skb(skb2);
 859 out:
 860         return err;
 861 }
 862
 863 static inline int
 864 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 865 {
 866         unsigned long d;
 867         unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1]));
 868         d = ct->status ^ status;
 869
 870         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 871                 /* unchangeable */
 872                 return -EINVAL;
 873
 874         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 875                 /* SEEN_REPLY bit can only be set */
 876                 return -EINVAL;
 877
 878
 879         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 880                 /* ASSURED bit can only be set */
 881                 return -EINVAL;
 882
 883         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 884 #ifndef CONFIG_IP_NF_NAT_NEEDED
 885                 return -EINVAL;
 886 #else
 887                 struct ip_nat_range range;
 888
 889                 if (cda[CTA_NAT_DST-1]) {
 890                         if (ctnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 891                                                 &range) < 0)
 892                                 return -EINVAL;
 893                         if (ip_nat_initialized(ct,
 894                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 895                                 return -EEXIST;
 896                         ip_nat_setup_info(ct, &range, hooknum);
 897                 }
 898                 if (cda[CTA_NAT_SRC-1]) {
 899                         if (ctnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 900                                                 &range) < 0)
 901                                 return -EINVAL;
 902                         if (ip_nat_initialized(ct,
 903                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 904                                 return -EEXIST;
 905                         ip_nat_setup_info(ct, &range, hooknum);
 906                 }
 907 #endif
 908         }
 909
 910         /* Be careful here, modifying NAT bits can screw up things,
 911          * so don't let users modify them directly if they don't pass
 912          * ip_nat_range. */
 913         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 914         return 0;
 915 }
 916
 917
 918 static inline int
 919 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 920 {
 921         struct nf_conntrack_helper *helper;
 922         struct nf_conn_help *help = nfct_help(ct);
 923         char *helpname;
 924         int err;
 925
 926         DEBUGP("entered %s\n", __FUNCTION__);
 927
 928         if (!help) {
 929                 /* FIXME: we need to reallocate and rehash */
 930                 return -EBUSY;
 931         }
 932
 933         /* don't change helper of sibling connections */
 934         if (ct->master)
 935                 return -EINVAL;
 936
 937         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 938         if (err < 0)
 939                 return err;
 940
 941         helper = __nf_conntrack_helper_find_byname(helpname);
 942         if (!helper) {
 943                 if (!strcmp(helpname, ""))
 944                         helper = NULL;
 945                 else
 946                         return -EINVAL;
 947         }
 948
 949         if (help->helper) {
 950                 if (!helper) {
 951                         /* we had a helper before ... */
 952                         nf_ct_remove_expectations(ct);
 953                         help->helper = NULL;
 954                 } else {
 955                         /* need to zero data of old helper */
 956                         memset(&help->help, 0, sizeof(help->help));
 957                 }
 958         }
 959
 960         help->helper = helper;
 961
 962         return 0;
 963 }
 964
 965 static inline int
 966 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 967 {
 968         u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 969
 970         if (!del_timer(&ct->timeout))
 971                 return -ETIME;
 972
 973         ct->timeout.expires = jiffies + timeout * HZ;
 974         add_timer(&ct->timeout);
 975
 976         return 0;
 977 }
 978
 979 static inline int
 980 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 981 {
 982         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 983         struct nf_conntrack_protocol *proto;
 984         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 985         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 986         int err = 0;
 987
 988         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 989
 990         proto = nf_ct_proto_find_get(l3num, npt);
 991
 992         if (proto->from_nfattr)
 993                 err = proto->from_nfattr(tb, ct);
 994         nf_ct_proto_put(proto);
 995
 996         return err;
 997 }
 998
 999 static int
1000 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
1001 {
1002         int err;
1003
1004         DEBUGP("entered %s\n", __FUNCTION__);
1005
1006         if (cda[CTA_HELP-1]) {
1007                 err = ctnetlink_change_helper(ct, cda);
1008                 if (err < 0)
1009                         return err;
1010         }
1011
1012         if (cda[CTA_TIMEOUT-1]) {
1013                 err = ctnetlink_change_timeout(ct, cda);
1014                 if (err < 0)
1015                         return err;
1016         }
1017
1018         if (cda[CTA_STATUS-1]) {
1019                 err = ctnetlink_change_status(ct, cda);
1020                 if (err < 0)
1021                         return err;
1022         }
1023
1024         if (cda[CTA_PROTOINFO-1]) {
1025                 err = ctnetlink_change_protoinfo(ct, cda);
1026                 if (err < 0)
1027                         return err;
1028         }
1029
1030 #if defined(CONFIG_NF_CONNTRACK_MARK)
1031         if (cda[CTA_MARK-1])
1032                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1033 #endif
1034
1035         DEBUGP("all done\n");
1036         return 0;
1037 }
1038
1039 static int
1040 ctnetlink_create_conntrack(struct nfattr *cda[],
1041                            struct nf_conntrack_tuple *otuple,
1042                            struct nf_conntrack_tuple *rtuple)
1043 {
1044         struct nf_conn *ct;
1045         int err = -EINVAL;
1046
1047         DEBUGP("entered %s\n", __FUNCTION__);
1048
1049         ct = nf_conntrack_alloc(otuple, rtuple);
1050         if (ct == NULL || IS_ERR(ct))
1051                 return -ENOMEM;
1052
1053         if (!cda[CTA_TIMEOUT-1])
1054                 goto err;
1055         ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
1056
1057         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1058         ct->status |= IPS_CONFIRMED;
1059
1060         err = ctnetlink_change_status(ct, cda);
1061         if (err < 0)
1062                 goto err;
1063
1064         if (cda[CTA_PROTOINFO-1]) {
1065                 err = ctnetlink_change_protoinfo(ct, cda);
1066                 if (err < 0)
1067                         return err;
1068         }
1069
1070 #if defined(CONFIG_NF_CONNTRACK_MARK)
1071         if (cda[CTA_MARK-1])
1072                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1073 #endif
1074
1075         add_timer(&ct->timeout);
1076         nf_conntrack_hash_insert(ct);
1077
1078         DEBUGP("conntrack with id %u inserted\n", ct->id);
1079         return 0;
1080
1081 err:
1082         nf_conntrack_free(ct);
1083         return err;
1084 }
1085
1086 static int
1087 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1088                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1089 {
1090         struct nf_conntrack_tuple otuple, rtuple;
1091         struct nf_conntrack_tuple_hash *h = NULL;
1092         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1093         u_int8_t u3 = nfmsg->nfgen_family;
1094         int err = 0;
1095
1096         DEBUGP("entered %s\n", __FUNCTION__);
1097
1098         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1099                 return -EINVAL;
1100
1101         if (cda[CTA_TUPLE_ORIG-1]) {
1102                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1103                 if (err < 0)
1104                         return err;
1105         }
1106
1107         if (cda[CTA_TUPLE_REPLY-1]) {
1108                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1109                 if (err < 0)
1110                         return err;
1111         }
1112
1113         write_lock_bh(&nf_conntrack_lock);
1114         if (cda[CTA_TUPLE_ORIG-1])
1115                 h = __nf_conntrack_find(&otuple, NULL);
1116         else if (cda[CTA_TUPLE_REPLY-1])
1117                 h = __nf_conntrack_find(&rtuple, NULL);
1118
1119         if (h == NULL) {
1120                 write_unlock_bh(&nf_conntrack_lock);
1121                 DEBUGP("no such conntrack, create new\n");
1122                 err = -ENOENT;
1123                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1124                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1125                 return err;
1126         }
1127         /* implicit 'else' */
1128
1129         /* we only allow nat config for new conntracks */
1130         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1131                 err = -EINVAL;
1132                 goto out_unlock;
1133         }
1134
1135         /* We manipulate the conntrack inside the global conntrack table lock,
1136          * so there's no need to increase the refcount */
1137         DEBUGP("conntrack found\n");
1138         err = -EEXIST;
1139         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1140                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1141
1142 out_unlock:
1143         write_unlock_bh(&nf_conntrack_lock);
1144         return err;
1145 }
1146
1147 /***********************************************************************
1148  * EXPECT
1149  ***********************************************************************/
1150
1151 static inline int
1152 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1153                          const struct nf_conntrack_tuple *tuple,
1154                          enum ctattr_expect type)
1155 {
1156         struct nfattr *nest_parms = NFA_NEST(skb, type);
1157
1158         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1159                 goto nfattr_failure;
1160
1161         NFA_NEST_END(skb, nest_parms);
1162
1163         return 0;
1164
1165 nfattr_failure:
1166         return -1;
1167 }
1168
1169 static inline int
1170 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1171                         const struct nf_conntrack_tuple *tuple,
1172                         const struct nf_conntrack_tuple *mask)
1173 {
1174         int ret;
1175         struct nf_conntrack_l3proto *l3proto;
1176         struct nf_conntrack_protocol *proto;
1177         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1178
1179         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1180         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1181         nf_ct_l3proto_put(l3proto);
1182
1183         if (unlikely(ret < 0))
1184                 goto nfattr_failure;
1185
1186         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1187         ret = ctnetlink_dump_tuples_proto(skb, mask, proto);
1188         nf_ct_proto_put(proto);
1189         if (unlikely(ret < 0))
1190                 goto nfattr_failure;
1191
1192         NFA_NEST_END(skb, nest_parms);
1193
1194         return 0;
1195
1196 nfattr_failure:
1197         return -1;
1198 }
1199
1200 static inline int
1201 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1202                           const struct nf_conntrack_expect *exp)
1203 {
1204         struct nf_conn *master = exp->master;
1205         u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1206         u_int32_t id = htonl(exp->id);
1207
1208         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1209                 goto nfattr_failure;
1210         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1211                 goto nfattr_failure;
1212         if (ctnetlink_exp_dump_tuple(skb,
1213                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1214                                  CTA_EXPECT_MASTER) < 0)
1215                 goto nfattr_failure;
1216
1217         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1218         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1219
1220         return 0;
1221
1222 nfattr_failure:
1223         return -1;
1224 }
1225
1226 static int
1227 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1228                     int event,
1229                     int nowait,
1230                     const struct nf_conntrack_expect *exp)
1231 {
1232         struct nlmsghdr *nlh;
1233         struct nfgenmsg *nfmsg;
1234         unsigned char *b;
1235
1236         b = skb->tail;
1237
1238         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1239         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1240         nfmsg  = NLMSG_DATA(nlh);
1241
1242         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
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         return skb->len;
1252
1253 nlmsg_failure:
1254 nfattr_failure:
1255         skb_trim(skb, b - skb->data);
1256         return -1;
1257 }
1258
1259 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1260 static int ctnetlink_expect_event(struct notifier_block *this,
1261                                   unsigned long events, void *ptr)
1262 {
1263         struct nlmsghdr *nlh;
1264         struct nfgenmsg *nfmsg;
1265         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1266         struct sk_buff *skb;
1267         unsigned int type;
1268         unsigned char *b;
1269         int flags = 0;
1270
1271         if (events & IPEXP_NEW) {
1272                 type = IPCTNL_MSG_EXP_NEW;
1273                 flags = NLM_F_CREATE|NLM_F_EXCL;
1274         } else
1275                 return NOTIFY_DONE;
1276
1277         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1278         if (!skb)
1279                 return NOTIFY_DONE;
1280
1281         b = skb->tail;
1282
1283         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1284         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1285         nfmsg = NLMSG_DATA(nlh);
1286
1287         nlh->nlmsg_flags    = flags;
1288         nfmsg->nfgen_family = exp->tuple.src.l3num;
1289         nfmsg->version      = NFNETLINK_V0;
1290         nfmsg->res_id       = 0;
1291
1292         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1293                 goto nfattr_failure;
1294
1295         nlh->nlmsg_len = skb->tail - b;
1296         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1297         return NOTIFY_DONE;
1298
1299 nlmsg_failure:
1300 nfattr_failure:
1301         kfree_skb(skb);
1302         return NOTIFY_DONE;
1303 }
1304 #endif
1305
1306 static int
1307 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1308 {
1309         struct nf_conntrack_expect *exp = NULL;
1310         struct list_head *i;
1311         u_int32_t *id = (u_int32_t *) &cb->args[0];
1312         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1313         u_int8_t l3proto = nfmsg->nfgen_family;
1314
1315         DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id);
1316
1317         read_lock_bh(&nf_conntrack_lock);
1318         list_for_each_prev(i, &nf_conntrack_expect_list) {
1319                 exp = (struct nf_conntrack_expect *) i;
1320                 if (l3proto && exp->tuple.src.l3num != l3proto)
1321                         continue;
1322                 if (exp->id <= *id)
1323                         continue;
1324                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1325                                             cb->nlh->nlmsg_seq,
1326                                             IPCTNL_MSG_EXP_NEW,
1327                                             1, exp) < 0)
1328                         goto out;
1329                 *id = exp->id;
1330         }
1331 out:
1332         read_unlock_bh(&nf_conntrack_lock);
1333
1334         DEBUGP("leaving, last id=%llu\n", *id);
1335
1336         return skb->len;
1337 }
1338
1339 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1340         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1341         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1342 };
1343
1344 static int
1345 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1346                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1347 {
1348         struct nf_conntrack_tuple tuple;
1349         struct nf_conntrack_expect *exp;
1350         struct sk_buff *skb2;
1351         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1352         u_int8_t u3 = nfmsg->nfgen_family;
1353         int err = 0;
1354
1355         DEBUGP("entered %s\n", __FUNCTION__);
1356
1357         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1358                 return -EINVAL;
1359
1360         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1361                 u32 rlen;
1362
1363                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1364                                                 ctnetlink_exp_dump_table,
1365                                                 ctnetlink_done)) != 0)
1366                         return -EINVAL;
1367                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1368                 if (rlen > skb->len)
1369                         rlen = skb->len;
1370                 skb_pull(skb, rlen);
1371                 return 0;
1372         }
1373
1374         if (cda[CTA_EXPECT_MASTER-1])
1375                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1376         else
1377                 return -EINVAL;
1378
1379         if (err < 0)
1380                 return err;
1381
1382         exp = nf_conntrack_expect_find(&tuple);
1383         if (!exp)
1384                 return -ENOENT;
1385
1386         if (cda[CTA_EXPECT_ID-1]) {
1387                 u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1388                 if (exp->id != ntohl(id)) {
1389                         nf_conntrack_expect_put(exp);
1390                         return -ENOENT;
1391                 }
1392         }
1393
1394         err = -ENOMEM;
1395         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1396         if (!skb2)
1397                 goto out;
1398         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
1399
1400         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1401                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1402                                       1, exp);
1403         if (err <= 0)
1404                 goto free;
1405
1406         nf_conntrack_expect_put(exp);
1407
1408         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1409
1410 free:
1411         kfree_skb(skb2);
1412 out:
1413         nf_conntrack_expect_put(exp);
1414         return err;
1415 }
1416
1417 static int
1418 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1419                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1420 {
1421         struct nf_conntrack_expect *exp, *tmp;
1422         struct nf_conntrack_tuple tuple;
1423         struct nf_conntrack_helper *h;
1424         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1425         u_int8_t u3 = nfmsg->nfgen_family;
1426         int err;
1427
1428         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1429                 return -EINVAL;
1430
1431         if (cda[CTA_EXPECT_TUPLE-1]) {
1432                 /* delete a single expect by tuple */
1433                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1434                 if (err < 0)
1435                         return err;
1436
1437                 /* bump usage count to 2 */
1438                 exp = nf_conntrack_expect_find(&tuple);
1439                 if (!exp)
1440                         return -ENOENT;
1441
1442                 if (cda[CTA_EXPECT_ID-1]) {
1443                         u_int32_t id =
1444                                 *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1445                         if (exp->id != ntohl(id)) {
1446                                 nf_conntrack_expect_put(exp);
1447                                 return -ENOENT;
1448                         }
1449                 }
1450
1451                 /* after list removal, usage count == 1 */
1452                 nf_conntrack_unexpect_related(exp);
1453                 /* have to put what we 'get' above.
1454                  * after this line usage count == 0 */
1455                 nf_conntrack_expect_put(exp);
1456         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1457                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1458
1459                 /* delete all expectations for this helper */
1460                 write_lock_bh(&nf_conntrack_lock);
1461                 h = __nf_conntrack_helper_find_byname(name);
1462                 if (!h) {
1463                         write_unlock_bh(&nf_conntrack_lock);
1464                         return -EINVAL;
1465                 }
1466                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1467                                          list) {
1468                         struct nf_conn_help *m_help = nfct_help(exp->master);
1469                         if (m_help->helper == h
1470                             && del_timer(&exp->timeout)) {
1471                                 nf_ct_unlink_expect(exp);
1472                                 nf_conntrack_expect_put(exp);
1473                         }
1474                 }
1475                 write_unlock_bh(&nf_conntrack_lock);
1476         } else {
1477                 /* This basically means we have to flush everything*/
1478                 write_lock_bh(&nf_conntrack_lock);
1479                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1480                                          list) {
1481                         if (del_timer(&exp->timeout)) {
1482                                 nf_ct_unlink_expect(exp);
1483                                 nf_conntrack_expect_put(exp);
1484                         }
1485                 }
1486                 write_unlock_bh(&nf_conntrack_lock);
1487         }
1488
1489         return 0;
1490 }
1491 static int
1492 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1493 {
1494         return -EOPNOTSUPP;
1495 }
1496
1497 static int
1498 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1499 {
1500         struct nf_conntrack_tuple tuple, mask, master_tuple;
1501         struct nf_conntrack_tuple_hash *h = NULL;
1502         struct nf_conntrack_expect *exp;
1503         struct nf_conn *ct;
1504         struct nf_conn_help *help;
1505         int err = 0;
1506
1507         DEBUGP("entered %s\n", __FUNCTION__);
1508
1509         /* caller guarantees that those three CTA_EXPECT_* exist */
1510         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1511         if (err < 0)
1512                 return err;
1513         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1514         if (err < 0)
1515                 return err;
1516         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1517         if (err < 0)
1518                 return err;
1519
1520         /* Look for master conntrack of this expectation */
1521         h = nf_conntrack_find_get(&master_tuple, NULL);
1522         if (!h)
1523                 return -ENOENT;
1524         ct = nf_ct_tuplehash_to_ctrack(h);
1525         help = nfct_help(ct);
1526
1527         if (!help || !help->helper) {
1528                 /* such conntrack hasn't got any helper, abort */
1529                 err = -EINVAL;
1530                 goto out;
1531         }
1532
1533         exp = nf_conntrack_expect_alloc(ct);
1534         if (!exp) {
1535                 err = -ENOMEM;
1536                 goto out;
1537         }
1538
1539         exp->expectfn = NULL;
1540         exp->flags = 0;
1541         exp->master = ct;
1542         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1543         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1544
1545         err = nf_conntrack_expect_related(exp);
1546         nf_conntrack_expect_put(exp);
1547
1548 out:
1549         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1550         return err;
1551 }
1552
1553 static int
1554 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1555                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1556 {
1557         struct nf_conntrack_tuple tuple;
1558         struct nf_conntrack_expect *exp;
1559         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1560         u_int8_t u3 = nfmsg->nfgen_family;
1561         int err = 0;
1562
1563         DEBUGP("entered %s\n", __FUNCTION__);
1564
1565         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1566                 return -EINVAL;
1567
1568         if (!cda[CTA_EXPECT_TUPLE-1]
1569             || !cda[CTA_EXPECT_MASK-1]
1570             || !cda[CTA_EXPECT_MASTER-1])
1571                 return -EINVAL;
1572
1573         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1574         if (err < 0)
1575                 return err;
1576
1577         write_lock_bh(&nf_conntrack_lock);
1578         exp = __nf_conntrack_expect_find(&tuple);
1579
1580         if (!exp) {
1581                 write_unlock_bh(&nf_conntrack_lock);
1582                 err = -ENOENT;
1583                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1584                         err = ctnetlink_create_expect(cda, u3);
1585                 return err;
1586         }
1587
1588         err = -EEXIST;
1589         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1590                 err = ctnetlink_change_expect(exp, cda);
1591         write_unlock_bh(&nf_conntrack_lock);
1592
1593         DEBUGP("leaving\n");
1594
1595         return err;
1596 }
1597
1598 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1599 static struct notifier_block ctnl_notifier = {
1600         .notifier_call  = ctnetlink_conntrack_event,
1601 };
1602
1603 static struct notifier_block ctnl_notifier_exp = {
1604         .notifier_call  = ctnetlink_expect_event,
1605 };
1606 #endif
1607
1608 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1609         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1610                                             .attr_count = CTA_MAX, },
1611         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1612                                             .attr_count = CTA_MAX, },
1613         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1614                                             .attr_count = CTA_MAX, },
1615         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1616                                             .attr_count = CTA_MAX, },
1617 };
1618
1619 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1620         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1621                                             .attr_count = CTA_EXPECT_MAX, },
1622         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1623                                             .attr_count = CTA_EXPECT_MAX, },
1624         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1625                                             .attr_count = CTA_EXPECT_MAX, },
1626 };
1627
1628 static struct nfnetlink_subsystem ctnl_subsys = {
1629         .name                           = "conntrack",
1630         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1631         .cb_count                       = IPCTNL_MSG_MAX,
1632         .cb                             = ctnl_cb,
1633 };
1634
1635 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1636         .name                           = "conntrack_expect",
1637         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1638         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1639         .cb                             = ctnl_exp_cb,
1640 };
1641
1642 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1643 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1644
1645 static int __init ctnetlink_init(void)
1646 {
1647         int ret;
1648
1649         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1650         ret = nfnetlink_subsys_register(&ctnl_subsys);
1651         if (ret < 0) {
1652                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1653                 goto err_out;
1654         }
1655
1656         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1657         if (ret < 0) {
1658                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1659                 goto err_unreg_subsys;
1660         }
1661
1662 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1663         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1664         if (ret < 0) {
1665                 printk("ctnetlink_init: cannot register notifier.\n");
1666                 goto err_unreg_exp_subsys;
1667         }
1668
1669         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1670         if (ret < 0) {
1671                 printk("ctnetlink_init: cannot expect register notifier.\n");
1672                 goto err_unreg_notifier;
1673         }
1674 #endif
1675
1676         return 0;
1677
1678 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1679 err_unreg_notifier:
1680         nf_conntrack_unregister_notifier(&ctnl_notifier);
1681 err_unreg_exp_subsys:
1682         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1683 #endif
1684 err_unreg_subsys:
1685         nfnetlink_subsys_unregister(&ctnl_subsys);
1686 err_out:
1687         return ret;
1688 }
1689
1690 static void __exit ctnetlink_exit(void)
1691 {
1692         printk("ctnetlink: unregistering from nfnetlink.\n");
1693
1694 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1695         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1696         nf_conntrack_unregister_notifier(&ctnl_notifier);
1697 #endif
1698
1699         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1700         nfnetlink_subsys_unregister(&ctnl_subsys);
1701         return;
1702 }
1703
1704 module_init(ctnetlink_init);
1705 module_exit(ctnetlink_exit);