SAFE public projects git trees. - safe/jmp/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) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net>
   8  *
   9  * Initial connection tracking via netlink development funded and
  10  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
  11  *
  12  * Further development of this code funded by Astaro AG (http://www.astaro.com)
  13  *
  14  * This software may be used and distributed according to the terms
  15  * of the GNU General Public License, incorporated herein by reference.
  16  */
  17
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/types.h>
  22 #include <linux/timer.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/errno.h>
  25 #include <linux/netlink.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/notifier.h>
  29
  30 #include <linux/netfilter.h>
  31 #include <net/netlink.h>
  32 #include <net/netfilter/nf_conntrack.h>
  33 #include <net/netfilter/nf_conntrack_core.h>
  34 #include <net/netfilter/nf_conntrack_expect.h>
  35 #include <net/netfilter/nf_conntrack_helper.h>
  36 #include <net/netfilter/nf_conntrack_l3proto.h>
  37 #include <net/netfilter/nf_conntrack_l4proto.h>
  38 #include <net/netfilter/nf_conntrack_tuple.h>
  39 #ifdef CONFIG_NF_NAT_NEEDED
  40 #include <net/netfilter/nf_nat_core.h>
  41 #include <net/netfilter/nf_nat_protocol.h>
  42 #endif
  43
  44 #include <linux/netfilter/nfnetlink.h>
  45 #include <linux/netfilter/nfnetlink_conntrack.h>
  46
  47 MODULE_LICENSE("GPL");
  48
  49 static char __initdata version[] = "0.93";
  50
  51 static inline int
  52 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  53                             const struct nf_conntrack_tuple *tuple,
  54                             struct nf_conntrack_l4proto *l4proto)
  55 {
  56         int ret = 0;
  57         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  58
  59         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  60
  61         if (likely(l4proto->tuple_to_nfattr))
  62                 ret = l4proto->tuple_to_nfattr(skb, tuple);
  63
  64         NFA_NEST_END(skb, nest_parms);
  65
  66         return ret;
  67
  68 nfattr_failure:
  69         return -1;
  70 }
  71
  72 static inline int
  73 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  74                          const struct nf_conntrack_tuple *tuple,
  75                          struct nf_conntrack_l3proto *l3proto)
  76 {
  77         int ret = 0;
  78         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  79
  80         if (likely(l3proto->tuple_to_nfattr))
  81                 ret = l3proto->tuple_to_nfattr(skb, tuple);
  82
  83         NFA_NEST_END(skb, nest_parms);
  84
  85         return ret;
  86
  87 nfattr_failure:
  88         return -1;
  89 }
  90
  91 static inline int
  92 ctnetlink_dump_tuples(struct sk_buff *skb,
  93                       const struct nf_conntrack_tuple *tuple)
  94 {
  95         int ret;
  96         struct nf_conntrack_l3proto *l3proto;
  97         struct nf_conntrack_l4proto *l4proto;
  98
  99         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 100         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 101         nf_ct_l3proto_put(l3proto);
 102
 103         if (unlikely(ret < 0))
 104                 return ret;
 105
 106         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 107         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
 108         nf_ct_l4proto_put(l4proto);
 109
 110         return ret;
 111 }
 112
 113 static inline int
 114 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 115 {
 116         __be32 status = htonl((u_int32_t) ct->status);
 117         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 118         return 0;
 119
 120 nfattr_failure:
 121         return -1;
 122 }
 123
 124 static inline int
 125 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 126 {
 127         long timeout_l = ct->timeout.expires - jiffies;
 128         __be32 timeout;
 129
 130         if (timeout_l < 0)
 131                 timeout = 0;
 132         else
 133                 timeout = htonl(timeout_l / HZ);
 134
 135         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 136         return 0;
 137
 138 nfattr_failure:
 139         return -1;
 140 }
 141
 142 static inline int
 143 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 144 {
 145         struct nf_conntrack_l4proto *l4proto = nf_ct_l4proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 146         struct nfattr *nest_proto;
 147         int ret;
 148
 149         if (!l4proto->to_nfattr) {
 150                 nf_ct_l4proto_put(l4proto);
 151                 return 0;
 152         }
 153
 154         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 155
 156         ret = l4proto->to_nfattr(skb, nest_proto, ct);
 157
 158         nf_ct_l4proto_put(l4proto);
 159
 160         NFA_NEST_END(skb, nest_proto);
 161
 162         return ret;
 163
 164 nfattr_failure:
 165         nf_ct_l4proto_put(l4proto);
 166         return -1;
 167 }
 168
 169 static inline int
 170 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 171 {
 172         struct nfattr *nest_helper;
 173         const struct nf_conn_help *help = nfct_help(ct);
 174         struct nf_conntrack_helper *helper;
 175
 176         if (!help)
 177                 return 0;
 178
 179         rcu_read_lock();
 180         helper = rcu_dereference(help->helper);
 181         if (!helper)
 182                 goto out;
 183
 184         nest_helper = NFA_NEST(skb, CTA_HELP);
 185         NFA_PUT(skb, CTA_HELP_NAME, strlen(helper->name), helper->name);
 186
 187         if (helper->to_nfattr)
 188                 helper->to_nfattr(skb, ct);
 189
 190         NFA_NEST_END(skb, nest_helper);
 191 out:
 192         rcu_read_unlock();
 193         return 0;
 194
 195 nfattr_failure:
 196         rcu_read_unlock();
 197         return -1;
 198 }
 199
 200 #ifdef CONFIG_NF_CT_ACCT
 201 static inline int
 202 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 203                         enum ip_conntrack_dir dir)
 204 {
 205         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 206         struct nfattr *nest_count = NFA_NEST(skb, type);
 207         __be32 tmp;
 208
 209         tmp = htonl(ct->counters[dir].packets);
 210         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 211
 212         tmp = htonl(ct->counters[dir].bytes);
 213         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 214
 215         NFA_NEST_END(skb, nest_count);
 216
 217         return 0;
 218
 219 nfattr_failure:
 220         return -1;
 221 }
 222 #else
 223 #define ctnetlink_dump_counters(a, b, c) (0)
 224 #endif
 225
 226 #ifdef CONFIG_NF_CONNTRACK_MARK
 227 static inline int
 228 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 229 {
 230         __be32 mark = htonl(ct->mark);
 231
 232         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 233         return 0;
 234
 235 nfattr_failure:
 236         return -1;
 237 }
 238 #else
 239 #define ctnetlink_dump_mark(a, b) (0)
 240 #endif
 241
 242 static inline int
 243 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 244 {
 245         __be32 id = htonl(ct->id);
 246         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 247         return 0;
 248
 249 nfattr_failure:
 250         return -1;
 251 }
 252
 253 static inline int
 254 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 255 {
 256         __be32 use = htonl(atomic_read(&ct->ct_general.use));
 257
 258         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 259         return 0;
 260
 261 nfattr_failure:
 262         return -1;
 263 }
 264
 265 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 266
 267 static int
 268 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 269                     int event, int nowait,
 270                     const struct nf_conn *ct)
 271 {
 272         struct nlmsghdr *nlh;
 273         struct nfgenmsg *nfmsg;
 274         struct nfattr *nest_parms;
 275         unsigned char *b = skb_tail_pointer(skb);
 276
 277         event |= NFNL_SUBSYS_CTNETLINK << 8;
 278         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 279         nfmsg  = NLMSG_DATA(nlh);
 280
 281         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 282         nfmsg->nfgen_family =
 283                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 284         nfmsg->version      = NFNETLINK_V0;
 285         nfmsg->res_id       = 0;
 286
 287         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 288         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 289                 goto nfattr_failure;
 290         NFA_NEST_END(skb, nest_parms);
 291
 292         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 293         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 294                 goto nfattr_failure;
 295         NFA_NEST_END(skb, nest_parms);
 296
 297         if (ctnetlink_dump_status(skb, ct) < 0 ||
 298             ctnetlink_dump_timeout(skb, ct) < 0 ||
 299             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 300             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 301             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 302             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 303             ctnetlink_dump_mark(skb, ct) < 0 ||
 304             ctnetlink_dump_id(skb, ct) < 0 ||
 305             ctnetlink_dump_use(skb, ct) < 0)
 306                 goto nfattr_failure;
 307
 308         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 309         return skb->len;
 310
 311 nlmsg_failure:
 312 nfattr_failure:
 313         nlmsg_trim(skb, b);
 314         return -1;
 315 }
 316
 317 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 318 static int ctnetlink_conntrack_event(struct notifier_block *this,
 319                                      unsigned long events, void *ptr)
 320 {
 321         struct nlmsghdr *nlh;
 322         struct nfgenmsg *nfmsg;
 323         struct nfattr *nest_parms;
 324         struct nf_conn *ct = (struct nf_conn *)ptr;
 325         struct sk_buff *skb;
 326         unsigned int type;
 327         sk_buff_data_t b;
 328         unsigned int flags = 0, group;
 329
 330         /* ignore our fake conntrack entry */
 331         if (ct == &nf_conntrack_untracked)
 332                 return NOTIFY_DONE;
 333
 334         if (events & IPCT_DESTROY) {
 335                 type = IPCTNL_MSG_CT_DELETE;
 336                 group = NFNLGRP_CONNTRACK_DESTROY;
 337         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 338                 type = IPCTNL_MSG_CT_NEW;
 339                 flags = NLM_F_CREATE|NLM_F_EXCL;
 340                 group = NFNLGRP_CONNTRACK_NEW;
 341         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 342                 type = IPCTNL_MSG_CT_NEW;
 343                 group = NFNLGRP_CONNTRACK_UPDATE;
 344         } else
 345                 return NOTIFY_DONE;
 346
 347         if (!nfnetlink_has_listeners(group))
 348                 return NOTIFY_DONE;
 349
 350         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 351         if (!skb)
 352                 return NOTIFY_DONE;
 353
 354         b = skb->tail;
 355
 356         type |= NFNL_SUBSYS_CTNETLINK << 8;
 357         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 358         nfmsg = NLMSG_DATA(nlh);
 359
 360         nlh->nlmsg_flags    = flags;
 361         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 362         nfmsg->version  = NFNETLINK_V0;
 363         nfmsg->res_id   = 0;
 364
 365         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 366         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 367                 goto nfattr_failure;
 368         NFA_NEST_END(skb, nest_parms);
 369
 370         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 371         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 372                 goto nfattr_failure;
 373         NFA_NEST_END(skb, nest_parms);
 374
 375         if (events & IPCT_DESTROY) {
 376                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 377                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 378                         goto nfattr_failure;
 379         } else {
 380                 if (ctnetlink_dump_status(skb, ct) < 0)
 381                         goto nfattr_failure;
 382
 383                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 384                         goto nfattr_failure;
 385
 386                 if (events & IPCT_PROTOINFO
 387                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 388                         goto nfattr_failure;
 389
 390                 if ((events & IPCT_HELPER || nfct_help(ct))
 391                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 392                         goto nfattr_failure;
 393
 394 #ifdef CONFIG_NF_CONNTRACK_MARK
 395                 if ((events & IPCT_MARK || ct->mark)
 396                     && ctnetlink_dump_mark(skb, ct) < 0)
 397                         goto nfattr_failure;
 398 #endif
 399
 400                 if (events & IPCT_COUNTER_FILLING &&
 401                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 402                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
 403                         goto nfattr_failure;
 404         }
 405
 406         nlh->nlmsg_len = skb->tail - b;
 407         nfnetlink_send(skb, 0, group, 0);
 408         return NOTIFY_DONE;
 409
 410 nlmsg_failure:
 411 nfattr_failure:
 412         kfree_skb(skb);
 413         return NOTIFY_DONE;
 414 }
 415 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 416
 417 static int ctnetlink_done(struct netlink_callback *cb)
 418 {
 419         if (cb->args[1])
 420                 nf_ct_put((struct nf_conn *)cb->args[1]);
 421         return 0;
 422 }
 423
 424 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 425
 426 static int
 427 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 428 {
 429         struct nf_conn *ct, *last;
 430         struct nf_conntrack_tuple_hash *h;
 431         struct list_head *i;
 432         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 433         u_int8_t l3proto = nfmsg->nfgen_family;
 434
 435         read_lock_bh(&nf_conntrack_lock);
 436         last = (struct nf_conn *)cb->args[1];
 437         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
 438 restart:
 439                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 440                         h = (struct nf_conntrack_tuple_hash *) i;
 441                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 442                                 continue;
 443                         ct = nf_ct_tuplehash_to_ctrack(h);
 444                         /* Dump entries of a given L3 protocol number.
 445                          * If it is not specified, ie. l3proto == 0,
 446                          * then dump everything. */
 447                         if (l3proto && L3PROTO(ct) != l3proto)
 448                                 continue;
 449                         if (cb->args[1]) {
 450                                 if (ct != last)
 451                                         continue;
 452                                 cb->args[1] = 0;
 453                         }
 454                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 455                                                 cb->nlh->nlmsg_seq,
 456                                                 IPCTNL_MSG_CT_NEW,
 457                                                 1, ct) < 0) {
 458                                 nf_conntrack_get(&ct->ct_general);
 459                                 cb->args[1] = (unsigned long)ct;
 460                                 goto out;
 461                         }
 462 #ifdef CONFIG_NF_CT_ACCT
 463                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 464                                                 IPCTNL_MSG_CT_GET_CTRZERO)
 465                                 memset(&ct->counters, 0, sizeof(ct->counters));
 466 #endif
 467                 }
 468                 if (cb->args[1]) {
 469                         cb->args[1] = 0;
 470                         goto restart;
 471                 }
 472         }
 473 out:
 474         read_unlock_bh(&nf_conntrack_lock);
 475         if (last)
 476                 nf_ct_put(last);
 477
 478         return skb->len;
 479 }
 480
 481 static inline int
 482 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 483 {
 484         struct nfattr *tb[CTA_IP_MAX];
 485         struct nf_conntrack_l3proto *l3proto;
 486         int ret = 0;
 487
 488         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 489
 490         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 491
 492         if (likely(l3proto->nfattr_to_tuple))
 493                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 494
 495         nf_ct_l3proto_put(l3proto);
 496
 497         return ret;
 498 }
 499
 500 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 501         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 502 };
 503
 504 static inline int
 505 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 506                             struct nf_conntrack_tuple *tuple)
 507 {
 508         struct nfattr *tb[CTA_PROTO_MAX];
 509         struct nf_conntrack_l4proto *l4proto;
 510         int ret = 0;
 511
 512         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 513
 514         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 515                 return -EINVAL;
 516
 517         if (!tb[CTA_PROTO_NUM-1])
 518                 return -EINVAL;
 519         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 520
 521         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 522
 523         if (likely(l4proto->nfattr_to_tuple))
 524                 ret = l4proto->nfattr_to_tuple(tb, tuple);
 525
 526         nf_ct_l4proto_put(l4proto);
 527
 528         return ret;
 529 }
 530
 531 static inline int
 532 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 533                       enum ctattr_tuple type, u_int8_t l3num)
 534 {
 535         struct nfattr *tb[CTA_TUPLE_MAX];
 536         int err;
 537
 538         memset(tuple, 0, sizeof(*tuple));
 539
 540         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 541
 542         if (!tb[CTA_TUPLE_IP-1])
 543                 return -EINVAL;
 544
 545         tuple->src.l3num = l3num;
 546
 547         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 548         if (err < 0)
 549                 return err;
 550
 551         if (!tb[CTA_TUPLE_PROTO-1])
 552                 return -EINVAL;
 553
 554         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 555         if (err < 0)
 556                 return err;
 557
 558         /* orig and expect tuples get DIR_ORIGINAL */
 559         if (type == CTA_TUPLE_REPLY)
 560                 tuple->dst.dir = IP_CT_DIR_REPLY;
 561         else
 562                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 563
 564         return 0;
 565 }
 566
 567 #ifdef CONFIG_NF_NAT_NEEDED
 568 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 569         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 570         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 571 };
 572
 573 static int nfnetlink_parse_nat_proto(struct nfattr *attr,
 574                                      const struct nf_conn *ct,
 575                                      struct nf_nat_range *range)
 576 {
 577         struct nfattr *tb[CTA_PROTONAT_MAX];
 578         struct nf_nat_protocol *npt;
 579
 580         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 581
 582         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 583                 return -EINVAL;
 584
 585         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 586
 587         if (!npt->nfattr_to_range) {
 588                 nf_nat_proto_put(npt);
 589                 return 0;
 590         }
 591
 592         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 593         if (npt->nfattr_to_range(tb, range) > 0)
 594                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 595
 596         nf_nat_proto_put(npt);
 597
 598         return 0;
 599 }
 600
 601 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 602         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 603         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 604 };
 605
 606 static inline int
 607 nfnetlink_parse_nat(struct nfattr *nat,
 608                     const struct nf_conn *ct, struct nf_nat_range *range)
 609 {
 610         struct nfattr *tb[CTA_NAT_MAX];
 611         int err;
 612
 613         memset(range, 0, sizeof(*range));
 614
 615         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 616
 617         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 618                 return -EINVAL;
 619
 620         if (tb[CTA_NAT_MINIP-1])
 621                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 622
 623         if (!tb[CTA_NAT_MAXIP-1])
 624                 range->max_ip = range->min_ip;
 625         else
 626                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 627
 628         if (range->min_ip)
 629                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 630
 631         if (!tb[CTA_NAT_PROTO-1])
 632                 return 0;
 633
 634         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 635         if (err < 0)
 636                 return err;
 637
 638         return 0;
 639 }
 640 #endif
 641
 642 static inline int
 643 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 644 {
 645         struct nfattr *tb[CTA_HELP_MAX];
 646
 647         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 648
 649         if (!tb[CTA_HELP_NAME-1])
 650                 return -EINVAL;
 651
 652         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 653
 654         return 0;
 655 }
 656
 657 static const size_t cta_min[CTA_MAX] = {
 658         [CTA_STATUS-1]          = sizeof(u_int32_t),
 659         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 660         [CTA_MARK-1]            = sizeof(u_int32_t),
 661         [CTA_USE-1]             = sizeof(u_int32_t),
 662         [CTA_ID-1]              = sizeof(u_int32_t)
 663 };
 664
 665 static int
 666 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 667                         struct nlmsghdr *nlh, struct nfattr *cda[])
 668 {
 669         struct nf_conntrack_tuple_hash *h;
 670         struct nf_conntrack_tuple tuple;
 671         struct nf_conn *ct;
 672         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 673         u_int8_t u3 = nfmsg->nfgen_family;
 674         int err = 0;
 675
 676         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 677                 return -EINVAL;
 678
 679         if (cda[CTA_TUPLE_ORIG-1])
 680                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 681         else if (cda[CTA_TUPLE_REPLY-1])
 682                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 683         else {
 684                 /* Flush the whole table */
 685                 nf_conntrack_flush();
 686                 return 0;
 687         }
 688
 689         if (err < 0)
 690                 return err;
 691
 692         h = nf_conntrack_find_get(&tuple, NULL);
 693         if (!h)
 694                 return -ENOENT;
 695
 696         ct = nf_ct_tuplehash_to_ctrack(h);
 697
 698         if (cda[CTA_ID-1]) {
 699                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
 700                 if (ct->id != id) {
 701                         nf_ct_put(ct);
 702                         return -ENOENT;
 703                 }
 704         }
 705         if (del_timer(&ct->timeout))
 706                 ct->timeout.function((unsigned long)ct);
 707
 708         nf_ct_put(ct);
 709
 710         return 0;
 711 }
 712
 713 static int
 714 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 715                         struct nlmsghdr *nlh, struct nfattr *cda[])
 716 {
 717         struct nf_conntrack_tuple_hash *h;
 718         struct nf_conntrack_tuple tuple;
 719         struct nf_conn *ct;
 720         struct sk_buff *skb2 = NULL;
 721         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 722         u_int8_t u3 = nfmsg->nfgen_family;
 723         int err = 0;
 724
 725         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 726 #ifndef CONFIG_NF_CT_ACCT
 727                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
 728                         return -ENOTSUPP;
 729 #endif
 730                 return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
 731                                           ctnetlink_done);
 732         }
 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                 return -EINVAL;
 743
 744         if (err < 0)
 745                 return err;
 746
 747         h = nf_conntrack_find_get(&tuple, NULL);
 748         if (!h)
 749                 return -ENOENT;
 750
 751         ct = nf_ct_tuplehash_to_ctrack(h);
 752
 753         err = -ENOMEM;
 754         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 755         if (!skb2) {
 756                 nf_ct_put(ct);
 757                 return -ENOMEM;
 758         }
 759
 760         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 761                                   IPCTNL_MSG_CT_NEW, 1, ct);
 762         nf_ct_put(ct);
 763         if (err <= 0)
 764                 goto free;
 765
 766         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 767         if (err < 0)
 768                 goto out;
 769
 770         return 0;
 771
 772 free:
 773         kfree_skb(skb2);
 774 out:
 775         return err;
 776 }
 777
 778 static inline int
 779 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 780 {
 781         unsigned long d;
 782         unsigned int status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));
 783         d = ct->status ^ status;
 784
 785         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 786                 /* unchangeable */
 787                 return -EINVAL;
 788
 789         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 790                 /* SEEN_REPLY bit can only be set */
 791                 return -EINVAL;
 792
 793
 794         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 795                 /* ASSURED bit can only be set */
 796                 return -EINVAL;
 797
 798         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 799 #ifndef CONFIG_NF_NAT_NEEDED
 800                 return -EINVAL;
 801 #else
 802                 struct nf_nat_range range;
 803
 804                 if (cda[CTA_NAT_DST-1]) {
 805                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 806                                                 &range) < 0)
 807                                 return -EINVAL;
 808                         if (nf_nat_initialized(ct,
 809                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 810                                 return -EEXIST;
 811                         nf_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
 812                 }
 813                 if (cda[CTA_NAT_SRC-1]) {
 814                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 815                                                 &range) < 0)
 816                                 return -EINVAL;
 817                         if (nf_nat_initialized(ct,
 818                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 819                                 return -EEXIST;
 820                         nf_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
 821                 }
 822 #endif
 823         }
 824
 825         /* Be careful here, modifying NAT bits can screw up things,
 826          * so don't let users modify them directly if they don't pass
 827          * nf_nat_range. */
 828         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 829         return 0;
 830 }
 831
 832
 833 static inline int
 834 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 835 {
 836         struct nf_conntrack_helper *helper;
 837         struct nf_conn_help *help = nfct_help(ct);
 838         char *helpname;
 839         int err;
 840
 841         /* don't change helper of sibling connections */
 842         if (ct->master)
 843                 return -EINVAL;
 844
 845         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 846         if (err < 0)
 847                 return err;
 848
 849         if (!strcmp(helpname, "")) {
 850                 if (help && help->helper) {
 851                         /* we had a helper before ... */
 852                         nf_ct_remove_expectations(ct);
 853                         rcu_assign_pointer(help->helper, NULL);
 854                 }
 855
 856                 return 0;
 857         }
 858
 859         if (!help) {
 860                 /* FIXME: we need to reallocate and rehash */
 861                 return -EBUSY;
 862         }
 863
 864         helper = __nf_conntrack_helper_find_byname(helpname);
 865         if (helper == NULL)
 866                 return -EINVAL;
 867
 868         if (help->helper == helper)
 869                 return 0;
 870
 871         if (help->helper)
 872                 return -EBUSY;
 873
 874         /* need to zero data of old helper */
 875         memset(&help->help, 0, sizeof(help->help));
 876         rcu_assign_pointer(help->helper, helper);
 877
 878         return 0;
 879 }
 880
 881 static inline int
 882 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 883 {
 884         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 885
 886         if (!del_timer(&ct->timeout))
 887                 return -ETIME;
 888
 889         ct->timeout.expires = jiffies + timeout * HZ;
 890         add_timer(&ct->timeout);
 891
 892         return 0;
 893 }
 894
 895 static inline int
 896 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 897 {
 898         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 899         struct nf_conntrack_l4proto *l4proto;
 900         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 901         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 902         int err = 0;
 903
 904         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 905
 906         l4proto = nf_ct_l4proto_find_get(l3num, npt);
 907
 908         if (l4proto->from_nfattr)
 909                 err = l4proto->from_nfattr(tb, ct);
 910         nf_ct_l4proto_put(l4proto);
 911
 912         return err;
 913 }
 914
 915 static int
 916 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
 917 {
 918         int err;
 919
 920         if (cda[CTA_HELP-1]) {
 921                 err = ctnetlink_change_helper(ct, cda);
 922                 if (err < 0)
 923                         return err;
 924         }
 925
 926         if (cda[CTA_TIMEOUT-1]) {
 927                 err = ctnetlink_change_timeout(ct, cda);
 928                 if (err < 0)
 929                         return err;
 930         }
 931
 932         if (cda[CTA_STATUS-1]) {
 933                 err = ctnetlink_change_status(ct, cda);
 934                 if (err < 0)
 935                         return err;
 936         }
 937
 938         if (cda[CTA_PROTOINFO-1]) {
 939                 err = ctnetlink_change_protoinfo(ct, cda);
 940                 if (err < 0)
 941                         return err;
 942         }
 943
 944 #if defined(CONFIG_NF_CONNTRACK_MARK)
 945         if (cda[CTA_MARK-1])
 946                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 947 #endif
 948
 949         return 0;
 950 }
 951
 952 static int
 953 ctnetlink_create_conntrack(struct nfattr *cda[],
 954                            struct nf_conntrack_tuple *otuple,
 955                            struct nf_conntrack_tuple *rtuple)
 956 {
 957         struct nf_conn *ct;
 958         int err = -EINVAL;
 959         struct nf_conn_help *help;
 960         struct nf_conntrack_helper *helper = NULL;
 961
 962         ct = nf_conntrack_alloc(otuple, rtuple);
 963         if (ct == NULL || IS_ERR(ct))
 964                 return -ENOMEM;
 965
 966         if (!cda[CTA_TIMEOUT-1])
 967                 goto err;
 968         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 969
 970         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
 971         ct->status |= IPS_CONFIRMED;
 972
 973         if (cda[CTA_STATUS-1]) {
 974                 err = ctnetlink_change_status(ct, cda);
 975                 if (err < 0)
 976                         goto err;
 977         }
 978
 979         if (cda[CTA_PROTOINFO-1]) {
 980                 err = ctnetlink_change_protoinfo(ct, cda);
 981                 if (err < 0)
 982                         goto err;
 983         }
 984
 985 #if defined(CONFIG_NF_CONNTRACK_MARK)
 986         if (cda[CTA_MARK-1])
 987                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 988 #endif
 989
 990         help = nfct_help(ct);
 991         if (help) {
 992                 helper = nf_ct_helper_find_get(rtuple);
 993                 /* not in hash table yet so not strictly necessary */
 994                 rcu_assign_pointer(help->helper, helper);
 995         }
 996
 997         add_timer(&ct->timeout);
 998         nf_conntrack_hash_insert(ct);
 999
1000         if (helper)
1001                 nf_ct_helper_put(helper);
1002
1003         return 0;
1004
1005 err:
1006         nf_conntrack_free(ct);
1007         return err;
1008 }
1009
1010 static int
1011 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1012                         struct nlmsghdr *nlh, struct nfattr *cda[])
1013 {
1014         struct nf_conntrack_tuple otuple, rtuple;
1015         struct nf_conntrack_tuple_hash *h = NULL;
1016         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1017         u_int8_t u3 = nfmsg->nfgen_family;
1018         int err = 0;
1019
1020         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1021                 return -EINVAL;
1022
1023         if (cda[CTA_TUPLE_ORIG-1]) {
1024                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1025                 if (err < 0)
1026                         return err;
1027         }
1028
1029         if (cda[CTA_TUPLE_REPLY-1]) {
1030                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1031                 if (err < 0)
1032                         return err;
1033         }
1034
1035         write_lock_bh(&nf_conntrack_lock);
1036         if (cda[CTA_TUPLE_ORIG-1])
1037                 h = __nf_conntrack_find(&otuple, NULL);
1038         else if (cda[CTA_TUPLE_REPLY-1])
1039                 h = __nf_conntrack_find(&rtuple, NULL);
1040
1041         if (h == NULL) {
1042                 write_unlock_bh(&nf_conntrack_lock);
1043                 err = -ENOENT;
1044                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1045                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1046                 return err;
1047         }
1048         /* implicit 'else' */
1049
1050         /* we only allow nat config for new conntracks */
1051         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1052                 err = -EINVAL;
1053                 goto out_unlock;
1054         }
1055
1056         /* We manipulate the conntrack inside the global conntrack table lock,
1057          * so there's no need to increase the refcount */
1058         err = -EEXIST;
1059         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1060                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1061
1062 out_unlock:
1063         write_unlock_bh(&nf_conntrack_lock);
1064         return err;
1065 }
1066
1067 /***********************************************************************
1068  * EXPECT
1069  ***********************************************************************/
1070
1071 static inline int
1072 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1073                          const struct nf_conntrack_tuple *tuple,
1074                          enum ctattr_expect type)
1075 {
1076         struct nfattr *nest_parms = NFA_NEST(skb, type);
1077
1078         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1079                 goto nfattr_failure;
1080
1081         NFA_NEST_END(skb, nest_parms);
1082
1083         return 0;
1084
1085 nfattr_failure:
1086         return -1;
1087 }
1088
1089 static inline int
1090 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1091                         const struct nf_conntrack_tuple *tuple,
1092                         const struct nf_conntrack_tuple *mask)
1093 {
1094         int ret;
1095         struct nf_conntrack_l3proto *l3proto;
1096         struct nf_conntrack_l4proto *l4proto;
1097         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1098
1099         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1100         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1101         nf_ct_l3proto_put(l3proto);
1102
1103         if (unlikely(ret < 0))
1104                 goto nfattr_failure;
1105
1106         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1107         ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);
1108         nf_ct_l4proto_put(l4proto);
1109         if (unlikely(ret < 0))
1110                 goto nfattr_failure;
1111
1112         NFA_NEST_END(skb, nest_parms);
1113
1114         return 0;
1115
1116 nfattr_failure:
1117         return -1;
1118 }
1119
1120 static inline int
1121 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1122                           const struct nf_conntrack_expect *exp)
1123 {
1124         struct nf_conn *master = exp->master;
1125         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1126         __be32 id = htonl(exp->id);
1127
1128         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1129                 goto nfattr_failure;
1130         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1131                 goto nfattr_failure;
1132         if (ctnetlink_exp_dump_tuple(skb,
1133                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1134                                  CTA_EXPECT_MASTER) < 0)
1135                 goto nfattr_failure;
1136
1137         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1138         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1139
1140         return 0;
1141
1142 nfattr_failure:
1143         return -1;
1144 }
1145
1146 static int
1147 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1148                     int event,
1149                     int nowait,
1150                     const struct nf_conntrack_expect *exp)
1151 {
1152         struct nlmsghdr *nlh;
1153         struct nfgenmsg *nfmsg;
1154         unsigned char *b = skb_tail_pointer(skb);
1155
1156         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1157         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1158         nfmsg  = NLMSG_DATA(nlh);
1159
1160         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1161         nfmsg->nfgen_family = exp->tuple.src.l3num;
1162         nfmsg->version      = NFNETLINK_V0;
1163         nfmsg->res_id       = 0;
1164
1165         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1166                 goto nfattr_failure;
1167
1168         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1169         return skb->len;
1170
1171 nlmsg_failure:
1172 nfattr_failure:
1173         nlmsg_trim(skb, b);
1174         return -1;
1175 }
1176
1177 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1178 static int ctnetlink_expect_event(struct notifier_block *this,
1179                                   unsigned long events, void *ptr)
1180 {
1181         struct nlmsghdr *nlh;
1182         struct nfgenmsg *nfmsg;
1183         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1184         struct sk_buff *skb;
1185         unsigned int type;
1186         sk_buff_data_t b;
1187         int flags = 0;
1188
1189         if (events & IPEXP_NEW) {
1190                 type = IPCTNL_MSG_EXP_NEW;
1191                 flags = NLM_F_CREATE|NLM_F_EXCL;
1192         } else
1193                 return NOTIFY_DONE;
1194
1195         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1196                 return NOTIFY_DONE;
1197
1198         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1199         if (!skb)
1200                 return NOTIFY_DONE;
1201
1202         b = skb->tail;
1203
1204         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1205         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1206         nfmsg = NLMSG_DATA(nlh);
1207
1208         nlh->nlmsg_flags    = flags;
1209         nfmsg->nfgen_family = exp->tuple.src.l3num;
1210         nfmsg->version      = NFNETLINK_V0;
1211         nfmsg->res_id       = 0;
1212
1213         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1214                 goto nfattr_failure;
1215
1216         nlh->nlmsg_len = skb->tail - b;
1217         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1218         return NOTIFY_DONE;
1219
1220 nlmsg_failure:
1221 nfattr_failure:
1222         kfree_skb(skb);
1223         return NOTIFY_DONE;
1224 }
1225 #endif
1226
1227 static int
1228 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1229 {
1230         struct nf_conntrack_expect *exp = NULL;
1231         struct list_head *i;
1232         u_int32_t *id = (u_int32_t *) &cb->args[0];
1233         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1234         u_int8_t l3proto = nfmsg->nfgen_family;
1235
1236         read_lock_bh(&nf_conntrack_lock);
1237         list_for_each_prev(i, &nf_conntrack_expect_list) {
1238                 exp = (struct nf_conntrack_expect *) i;
1239                 if (l3proto && exp->tuple.src.l3num != l3proto)
1240                         continue;
1241                 if (exp->id <= *id)
1242                         continue;
1243                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1244                                             cb->nlh->nlmsg_seq,
1245                                             IPCTNL_MSG_EXP_NEW,
1246                                             1, exp) < 0)
1247                         goto out;
1248                 *id = exp->id;
1249         }
1250 out:
1251         read_unlock_bh(&nf_conntrack_lock);
1252
1253         return skb->len;
1254 }
1255
1256 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1257         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1258         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1259 };
1260
1261 static int
1262 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1263                      struct nlmsghdr *nlh, struct nfattr *cda[])
1264 {
1265         struct nf_conntrack_tuple tuple;
1266         struct nf_conntrack_expect *exp;
1267         struct sk_buff *skb2;
1268         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1269         u_int8_t u3 = nfmsg->nfgen_family;
1270         int err = 0;
1271
1272         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1273                 return -EINVAL;
1274
1275         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1276                 return netlink_dump_start(ctnl, skb, nlh,
1277                                           ctnetlink_exp_dump_table,
1278                                           ctnetlink_done);
1279         }
1280
1281         if (cda[CTA_EXPECT_MASTER-1])
1282                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1283         else
1284                 return -EINVAL;
1285
1286         if (err < 0)
1287                 return err;
1288
1289         exp = nf_conntrack_expect_find_get(&tuple);
1290         if (!exp)
1291                 return -ENOENT;
1292
1293         if (cda[CTA_EXPECT_ID-1]) {
1294                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1295                 if (exp->id != ntohl(id)) {
1296                         nf_conntrack_expect_put(exp);
1297                         return -ENOENT;
1298                 }
1299         }
1300
1301         err = -ENOMEM;
1302         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1303         if (!skb2)
1304                 goto out;
1305
1306         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1307                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1308                                       1, exp);
1309         if (err <= 0)
1310                 goto free;
1311
1312         nf_conntrack_expect_put(exp);
1313
1314         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1315
1316 free:
1317         kfree_skb(skb2);
1318 out:
1319         nf_conntrack_expect_put(exp);
1320         return err;
1321 }
1322
1323 static int
1324 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1325                      struct nlmsghdr *nlh, struct nfattr *cda[])
1326 {
1327         struct nf_conntrack_expect *exp, *tmp;
1328         struct nf_conntrack_tuple tuple;
1329         struct nf_conntrack_helper *h;
1330         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1331         u_int8_t u3 = nfmsg->nfgen_family;
1332         int err;
1333
1334         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1335                 return -EINVAL;
1336
1337         if (cda[CTA_EXPECT_TUPLE-1]) {
1338                 /* delete a single expect by tuple */
1339                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1340                 if (err < 0)
1341                         return err;
1342
1343                 /* bump usage count to 2 */
1344                 exp = nf_conntrack_expect_find_get(&tuple);
1345                 if (!exp)
1346                         return -ENOENT;
1347
1348                 if (cda[CTA_EXPECT_ID-1]) {
1349                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1350                         if (exp->id != ntohl(id)) {
1351                                 nf_conntrack_expect_put(exp);
1352                                 return -ENOENT;
1353                         }
1354                 }
1355
1356                 /* after list removal, usage count == 1 */
1357                 nf_conntrack_unexpect_related(exp);
1358                 /* have to put what we 'get' above.
1359                  * after this line usage count == 0 */
1360                 nf_conntrack_expect_put(exp);
1361         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1362                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1363
1364                 /* delete all expectations for this helper */
1365                 write_lock_bh(&nf_conntrack_lock);
1366                 h = __nf_conntrack_helper_find_byname(name);
1367                 if (!h) {
1368                         write_unlock_bh(&nf_conntrack_lock);
1369                         return -EINVAL;
1370                 }
1371                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1372                                          list) {
1373                         struct nf_conn_help *m_help = nfct_help(exp->master);
1374                         if (m_help->helper == h
1375                             && del_timer(&exp->timeout)) {
1376                                 nf_ct_unlink_expect(exp);
1377                                 nf_conntrack_expect_put(exp);
1378                         }
1379                 }
1380                 write_unlock_bh(&nf_conntrack_lock);
1381         } else {
1382                 /* This basically means we have to flush everything*/
1383                 write_lock_bh(&nf_conntrack_lock);
1384                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1385                                          list) {
1386                         if (del_timer(&exp->timeout)) {
1387                                 nf_ct_unlink_expect(exp);
1388                                 nf_conntrack_expect_put(exp);
1389                         }
1390                 }
1391                 write_unlock_bh(&nf_conntrack_lock);
1392         }
1393
1394         return 0;
1395 }
1396 static int
1397 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1398 {
1399         return -EOPNOTSUPP;
1400 }
1401
1402 static int
1403 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1404 {
1405         struct nf_conntrack_tuple tuple, mask, master_tuple;
1406         struct nf_conntrack_tuple_hash *h = NULL;
1407         struct nf_conntrack_expect *exp;
1408         struct nf_conn *ct;
1409         struct nf_conn_help *help;
1410         int err = 0;
1411
1412         /* caller guarantees that those three CTA_EXPECT_* exist */
1413         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1414         if (err < 0)
1415                 return err;
1416         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1417         if (err < 0)
1418                 return err;
1419         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1420         if (err < 0)
1421                 return err;
1422
1423         /* Look for master conntrack of this expectation */
1424         h = nf_conntrack_find_get(&master_tuple, NULL);
1425         if (!h)
1426                 return -ENOENT;
1427         ct = nf_ct_tuplehash_to_ctrack(h);
1428         help = nfct_help(ct);
1429
1430         if (!help || !help->helper) {
1431                 /* such conntrack hasn't got any helper, abort */
1432                 err = -EINVAL;
1433                 goto out;
1434         }
1435
1436         exp = nf_conntrack_expect_alloc(ct);
1437         if (!exp) {
1438                 err = -ENOMEM;
1439                 goto out;
1440         }
1441
1442         exp->expectfn = NULL;
1443         exp->flags = 0;
1444         exp->master = ct;
1445         exp->helper = NULL;
1446         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1447         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1448
1449         err = nf_conntrack_expect_related(exp);
1450         nf_conntrack_expect_put(exp);
1451
1452 out:
1453         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1454         return err;
1455 }
1456
1457 static int
1458 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1459                      struct nlmsghdr *nlh, struct nfattr *cda[])
1460 {
1461         struct nf_conntrack_tuple tuple;
1462         struct nf_conntrack_expect *exp;
1463         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1464         u_int8_t u3 = nfmsg->nfgen_family;
1465         int err = 0;
1466
1467         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1468                 return -EINVAL;
1469
1470         if (!cda[CTA_EXPECT_TUPLE-1]
1471             || !cda[CTA_EXPECT_MASK-1]
1472             || !cda[CTA_EXPECT_MASTER-1])
1473                 return -EINVAL;
1474
1475         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1476         if (err < 0)
1477                 return err;
1478
1479         write_lock_bh(&nf_conntrack_lock);
1480         exp = __nf_conntrack_expect_find(&tuple);
1481
1482         if (!exp) {
1483                 write_unlock_bh(&nf_conntrack_lock);
1484                 err = -ENOENT;
1485                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1486                         err = ctnetlink_create_expect(cda, u3);
1487                 return err;
1488         }
1489
1490         err = -EEXIST;
1491         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1492                 err = ctnetlink_change_expect(exp, cda);
1493         write_unlock_bh(&nf_conntrack_lock);
1494
1495         return err;
1496 }
1497
1498 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1499 static struct notifier_block ctnl_notifier = {
1500         .notifier_call  = ctnetlink_conntrack_event,
1501 };
1502
1503 static struct notifier_block ctnl_notifier_exp = {
1504         .notifier_call  = ctnetlink_expect_event,
1505 };
1506 #endif
1507
1508 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1509         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1510                                             .attr_count = CTA_MAX, },
1511         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1512                                             .attr_count = CTA_MAX, },
1513         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1514                                             .attr_count = CTA_MAX, },
1515         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1516                                             .attr_count = CTA_MAX, },
1517 };
1518
1519 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1520         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1521                                             .attr_count = CTA_EXPECT_MAX, },
1522         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1523                                             .attr_count = CTA_EXPECT_MAX, },
1524         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1525                                             .attr_count = CTA_EXPECT_MAX, },
1526 };
1527
1528 static struct nfnetlink_subsystem ctnl_subsys = {
1529         .name                           = "conntrack",
1530         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1531         .cb_count                       = IPCTNL_MSG_MAX,
1532         .cb                             = ctnl_cb,
1533 };
1534
1535 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1536         .name                           = "conntrack_expect",
1537         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1538         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1539         .cb                             = ctnl_exp_cb,
1540 };
1541
1542 MODULE_ALIAS("ip_conntrack_netlink");
1543 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1544 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1545
1546 static int __init ctnetlink_init(void)
1547 {
1548         int ret;
1549
1550         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1551         ret = nfnetlink_subsys_register(&ctnl_subsys);
1552         if (ret < 0) {
1553                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1554                 goto err_out;
1555         }
1556
1557         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1558         if (ret < 0) {
1559                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1560                 goto err_unreg_subsys;
1561         }
1562
1563 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1564         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1565         if (ret < 0) {
1566                 printk("ctnetlink_init: cannot register notifier.\n");
1567                 goto err_unreg_exp_subsys;
1568         }
1569
1570         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1571         if (ret < 0) {
1572                 printk("ctnetlink_init: cannot expect register notifier.\n");
1573                 goto err_unreg_notifier;
1574         }
1575 #endif
1576
1577         return 0;
1578
1579 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1580 err_unreg_notifier:
1581         nf_conntrack_unregister_notifier(&ctnl_notifier);
1582 err_unreg_exp_subsys:
1583         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1584 #endif
1585 err_unreg_subsys:
1586         nfnetlink_subsys_unregister(&ctnl_subsys);
1587 err_out:
1588         return ret;
1589 }
1590
1591 static void __exit ctnetlink_exit(void)
1592 {
1593         printk("ctnetlink: unregistering from nfnetlink.\n");
1594
1595 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1596         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1597         nf_conntrack_unregister_notifier(&ctnl_notifier);
1598 #endif
1599
1600         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1601         nfnetlink_subsys_unregister(&ctnl_subsys);
1602         return;
1603 }
1604
1605 module_init(ctnetlink_init);
1606 module_exit(ctnetlink_exit);