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_expect.h>
  39 #include <net/netfilter/nf_conntrack_helper.h>
  40 #include <net/netfilter/nf_conntrack_l3proto.h>
  41 #include <net/netfilter/nf_conntrack_l4proto.h>
  42 #include <net/netfilter/nf_conntrack_tuple.h>
  43 #ifdef CONFIG_NF_NAT_NEEDED
  44 #include <net/netfilter/nf_nat_core.h>
  45 #include <net/netfilter/nf_nat_protocol.h>
  46 #endif
  47
  48 #include <linux/netfilter/nfnetlink.h>
  49 #include <linux/netfilter/nfnetlink_conntrack.h>
  50
  51 MODULE_LICENSE("GPL");
  52
  53 static char __initdata version[] = "0.93";
  54
  55 static inline int
  56 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  57                             const struct nf_conntrack_tuple *tuple,
  58                             struct nf_conntrack_l4proto *l4proto)
  59 {
  60         int ret = 0;
  61         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  62
  63         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  64
  65         if (likely(l4proto->tuple_to_nfattr))
  66                 ret = l4proto->tuple_to_nfattr(skb, tuple);
  67
  68         NFA_NEST_END(skb, nest_parms);
  69
  70         return ret;
  71
  72 nfattr_failure:
  73         return -1;
  74 }
  75
  76 static inline int
  77 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  78                          const struct nf_conntrack_tuple *tuple,
  79                          struct nf_conntrack_l3proto *l3proto)
  80 {
  81         int ret = 0;
  82         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  83
  84         if (likely(l3proto->tuple_to_nfattr))
  85                 ret = l3proto->tuple_to_nfattr(skb, tuple);
  86
  87         NFA_NEST_END(skb, nest_parms);
  88
  89         return ret;
  90
  91 nfattr_failure:
  92         return -1;
  93 }
  94
  95 static inline int
  96 ctnetlink_dump_tuples(struct sk_buff *skb,
  97                       const struct nf_conntrack_tuple *tuple)
  98 {
  99         int ret;
 100         struct nf_conntrack_l3proto *l3proto;
 101         struct nf_conntrack_l4proto *l4proto;
 102
 103         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 104         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 105         nf_ct_l3proto_put(l3proto);
 106
 107         if (unlikely(ret < 0))
 108                 return ret;
 109
 110         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 111         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
 112         nf_ct_l4proto_put(l4proto);
 113
 114         return ret;
 115 }
 116
 117 static inline int
 118 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 119 {
 120         __be32 status = htonl((u_int32_t) ct->status);
 121         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 122         return 0;
 123
 124 nfattr_failure:
 125         return -1;
 126 }
 127
 128 static inline int
 129 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 130 {
 131         long timeout_l = ct->timeout.expires - jiffies;
 132         __be32 timeout;
 133
 134         if (timeout_l < 0)
 135                 timeout = 0;
 136         else
 137                 timeout = htonl(timeout_l / HZ);
 138
 139         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 140         return 0;
 141
 142 nfattr_failure:
 143         return -1;
 144 }
 145
 146 static inline int
 147 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 148 {
 149         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);
 150         struct nfattr *nest_proto;
 151         int ret;
 152
 153         if (!l4proto->to_nfattr) {
 154                 nf_ct_l4proto_put(l4proto);
 155                 return 0;
 156         }
 157
 158         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 159
 160         ret = l4proto->to_nfattr(skb, nest_proto, ct);
 161
 162         nf_ct_l4proto_put(l4proto);
 163
 164         NFA_NEST_END(skb, nest_proto);
 165
 166         return ret;
 167
 168 nfattr_failure:
 169         nf_ct_l4proto_put(l4proto);
 170         return -1;
 171 }
 172
 173 static inline int
 174 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 175 {
 176         struct nfattr *nest_helper;
 177         const struct nf_conn_help *help = nfct_help(ct);
 178
 179         if (!help || !help->helper)
 180                 return 0;
 181
 182         nest_helper = NFA_NEST(skb, CTA_HELP);
 183         NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
 184
 185         if (help->helper->to_nfattr)
 186                 help->helper->to_nfattr(skb, ct);
 187
 188         NFA_NEST_END(skb, nest_helper);
 189
 190         return 0;
 191
 192 nfattr_failure:
 193         return -1;
 194 }
 195
 196 #ifdef CONFIG_NF_CT_ACCT
 197 static inline int
 198 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 199                         enum ip_conntrack_dir dir)
 200 {
 201         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 202         struct nfattr *nest_count = NFA_NEST(skb, type);
 203         __be32 tmp;
 204
 205         tmp = htonl(ct->counters[dir].packets);
 206         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 207
 208         tmp = htonl(ct->counters[dir].bytes);
 209         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 210
 211         NFA_NEST_END(skb, nest_count);
 212
 213         return 0;
 214
 215 nfattr_failure:
 216         return -1;
 217 }
 218 #else
 219 #define ctnetlink_dump_counters(a, b, c) (0)
 220 #endif
 221
 222 #ifdef CONFIG_NF_CONNTRACK_MARK
 223 static inline int
 224 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 225 {
 226         __be32 mark = htonl(ct->mark);
 227
 228         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 229         return 0;
 230
 231 nfattr_failure:
 232         return -1;
 233 }
 234 #else
 235 #define ctnetlink_dump_mark(a, b) (0)
 236 #endif
 237
 238 static inline int
 239 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 240 {
 241         __be32 id = htonl(ct->id);
 242         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 243         return 0;
 244
 245 nfattr_failure:
 246         return -1;
 247 }
 248
 249 static inline int
 250 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 251 {
 252         __be32 use = htonl(atomic_read(&ct->ct_general.use));
 253
 254         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 255         return 0;
 256
 257 nfattr_failure:
 258         return -1;
 259 }
 260
 261 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 262
 263 static int
 264 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 265                     int event, int nowait,
 266                     const struct nf_conn *ct)
 267 {
 268         struct nlmsghdr *nlh;
 269         struct nfgenmsg *nfmsg;
 270         struct nfattr *nest_parms;
 271         unsigned char *b = skb_tail_pointer(skb);
 272
 273         event |= NFNL_SUBSYS_CTNETLINK << 8;
 274         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 275         nfmsg  = NLMSG_DATA(nlh);
 276
 277         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 278         nfmsg->nfgen_family =
 279                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 280         nfmsg->version      = NFNETLINK_V0;
 281         nfmsg->res_id       = 0;
 282
 283         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 284         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 285                 goto nfattr_failure;
 286         NFA_NEST_END(skb, nest_parms);
 287
 288         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 289         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 290                 goto nfattr_failure;
 291         NFA_NEST_END(skb, nest_parms);
 292
 293         if (ctnetlink_dump_status(skb, ct) < 0 ||
 294             ctnetlink_dump_timeout(skb, ct) < 0 ||
 295             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 296             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 297             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 298             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 299             ctnetlink_dump_mark(skb, ct) < 0 ||
 300             ctnetlink_dump_id(skb, ct) < 0 ||
 301             ctnetlink_dump_use(skb, ct) < 0)
 302                 goto nfattr_failure;
 303
 304         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 305         return skb->len;
 306
 307 nlmsg_failure:
 308 nfattr_failure:
 309         skb_trim(skb, b - skb->data);
 310         return -1;
 311 }
 312
 313 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 314 static int ctnetlink_conntrack_event(struct notifier_block *this,
 315                                      unsigned long events, void *ptr)
 316 {
 317         struct nlmsghdr *nlh;
 318         struct nfgenmsg *nfmsg;
 319         struct nfattr *nest_parms;
 320         struct nf_conn *ct = (struct nf_conn *)ptr;
 321         struct sk_buff *skb;
 322         unsigned int type;
 323         sk_buff_data_t b;
 324         unsigned int flags = 0, group;
 325
 326         /* ignore our fake conntrack entry */
 327         if (ct == &nf_conntrack_untracked)
 328                 return NOTIFY_DONE;
 329
 330         if (events & IPCT_DESTROY) {
 331                 type = IPCTNL_MSG_CT_DELETE;
 332                 group = NFNLGRP_CONNTRACK_DESTROY;
 333         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 334                 type = IPCTNL_MSG_CT_NEW;
 335                 flags = NLM_F_CREATE|NLM_F_EXCL;
 336                 group = NFNLGRP_CONNTRACK_NEW;
 337         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 338                 type = IPCTNL_MSG_CT_NEW;
 339                 group = NFNLGRP_CONNTRACK_UPDATE;
 340         } else
 341                 return NOTIFY_DONE;
 342
 343         if (!nfnetlink_has_listeners(group))
 344                 return NOTIFY_DONE;
 345
 346         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 347         if (!skb)
 348                 return NOTIFY_DONE;
 349
 350         b = skb->tail;
 351
 352         type |= NFNL_SUBSYS_CTNETLINK << 8;
 353         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 354         nfmsg = NLMSG_DATA(nlh);
 355
 356         nlh->nlmsg_flags    = flags;
 357         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 358         nfmsg->version  = NFNETLINK_V0;
 359         nfmsg->res_id   = 0;
 360
 361         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 362         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 363                 goto nfattr_failure;
 364         NFA_NEST_END(skb, nest_parms);
 365
 366         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 367         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 368                 goto nfattr_failure;
 369         NFA_NEST_END(skb, nest_parms);
 370
 371         if (events & IPCT_DESTROY) {
 372                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 373                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 374                         goto nfattr_failure;
 375         } else {
 376                 if (ctnetlink_dump_status(skb, ct) < 0)
 377                         goto nfattr_failure;
 378
 379                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 380                         goto nfattr_failure;
 381
 382                 if (events & IPCT_PROTOINFO
 383                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 384                         goto nfattr_failure;
 385
 386                 if ((events & IPCT_HELPER || nfct_help(ct))
 387                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 388                         goto nfattr_failure;
 389
 390 #ifdef CONFIG_NF_CONNTRACK_MARK
 391                 if ((events & IPCT_MARK || ct->mark)
 392                     && ctnetlink_dump_mark(skb, ct) < 0)
 393                         goto nfattr_failure;
 394 #endif
 395
 396                 if (events & IPCT_COUNTER_FILLING &&
 397                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 398                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
 399                         goto nfattr_failure;
 400         }
 401
 402         nlh->nlmsg_len = skb->tail - b;
 403         nfnetlink_send(skb, 0, group, 0);
 404         return NOTIFY_DONE;
 405
 406 nlmsg_failure:
 407 nfattr_failure:
 408         kfree_skb(skb);
 409         return NOTIFY_DONE;
 410 }
 411 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 412
 413 static int ctnetlink_done(struct netlink_callback *cb)
 414 {
 415         if (cb->args[1])
 416                 nf_ct_put((struct nf_conn *)cb->args[1]);
 417         return 0;
 418 }
 419
 420 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 421
 422 static int
 423 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 424 {
 425         struct nf_conn *ct, *last;
 426         struct nf_conntrack_tuple_hash *h;
 427         struct list_head *i;
 428         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 429         u_int8_t l3proto = nfmsg->nfgen_family;
 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 (NF_CT_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 #ifdef CONFIG_NF_CT_ACCT
 459                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 460                                                 IPCTNL_MSG_CT_GET_CTRZERO)
 461                                 memset(&ct->counters, 0, sizeof(ct->counters));
 462 #endif
 463                 }
 464                 if (cb->args[1]) {
 465                         cb->args[1] = 0;
 466                         goto restart;
 467                 }
 468         }
 469 out:
 470         read_unlock_bh(&nf_conntrack_lock);
 471         if (last)
 472                 nf_ct_put(last);
 473
 474         return skb->len;
 475 }
 476
 477 static inline int
 478 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 479 {
 480         struct nfattr *tb[CTA_IP_MAX];
 481         struct nf_conntrack_l3proto *l3proto;
 482         int ret = 0;
 483
 484         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 485
 486         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 487
 488         if (likely(l3proto->nfattr_to_tuple))
 489                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 490
 491         nf_ct_l3proto_put(l3proto);
 492
 493         return ret;
 494 }
 495
 496 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 497         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 498 };
 499
 500 static inline int
 501 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 502                             struct nf_conntrack_tuple *tuple)
 503 {
 504         struct nfattr *tb[CTA_PROTO_MAX];
 505         struct nf_conntrack_l4proto *l4proto;
 506         int ret = 0;
 507
 508         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 509
 510         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 511                 return -EINVAL;
 512
 513         if (!tb[CTA_PROTO_NUM-1])
 514                 return -EINVAL;
 515         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 516
 517         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 518
 519         if (likely(l4proto->nfattr_to_tuple))
 520                 ret = l4proto->nfattr_to_tuple(tb, tuple);
 521
 522         nf_ct_l4proto_put(l4proto);
 523
 524         return ret;
 525 }
 526
 527 static inline int
 528 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 529                       enum ctattr_tuple type, u_int8_t l3num)
 530 {
 531         struct nfattr *tb[CTA_TUPLE_MAX];
 532         int err;
 533
 534         memset(tuple, 0, sizeof(*tuple));
 535
 536         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 537
 538         if (!tb[CTA_TUPLE_IP-1])
 539                 return -EINVAL;
 540
 541         tuple->src.l3num = l3num;
 542
 543         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 544         if (err < 0)
 545                 return err;
 546
 547         if (!tb[CTA_TUPLE_PROTO-1])
 548                 return -EINVAL;
 549
 550         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 551         if (err < 0)
 552                 return err;
 553
 554         /* orig and expect tuples get DIR_ORIGINAL */
 555         if (type == CTA_TUPLE_REPLY)
 556                 tuple->dst.dir = IP_CT_DIR_REPLY;
 557         else
 558                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 559
 560         return 0;
 561 }
 562
 563 #ifdef CONFIG_NF_NAT_NEEDED
 564 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 565         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 566         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 567 };
 568
 569 static int nfnetlink_parse_nat_proto(struct nfattr *attr,
 570                                      const struct nf_conn *ct,
 571                                      struct nf_nat_range *range)
 572 {
 573         struct nfattr *tb[CTA_PROTONAT_MAX];
 574         struct nf_nat_protocol *npt;
 575
 576         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 577
 578         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 579                 return -EINVAL;
 580
 581         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 582
 583         if (!npt->nfattr_to_range) {
 584                 nf_nat_proto_put(npt);
 585                 return 0;
 586         }
 587
 588         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 589         if (npt->nfattr_to_range(tb, range) > 0)
 590                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 591
 592         nf_nat_proto_put(npt);
 593
 594         return 0;
 595 }
 596
 597 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 598         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 599         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 600 };
 601
 602 static inline int
 603 nfnetlink_parse_nat(struct nfattr *nat,
 604                     const struct nf_conn *ct, struct nf_nat_range *range)
 605 {
 606         struct nfattr *tb[CTA_NAT_MAX];
 607         int err;
 608
 609         memset(range, 0, sizeof(*range));
 610
 611         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 612
 613         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 614                 return -EINVAL;
 615
 616         if (tb[CTA_NAT_MINIP-1])
 617                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 618
 619         if (!tb[CTA_NAT_MAXIP-1])
 620                 range->max_ip = range->min_ip;
 621         else
 622                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 623
 624         if (range->min_ip)
 625                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 626
 627         if (!tb[CTA_NAT_PROTO-1])
 628                 return 0;
 629
 630         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 631         if (err < 0)
 632                 return err;
 633
 634         return 0;
 635 }
 636 #endif
 637
 638 static inline int
 639 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 640 {
 641         struct nfattr *tb[CTA_HELP_MAX];
 642
 643         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 644
 645         if (!tb[CTA_HELP_NAME-1])
 646                 return -EINVAL;
 647
 648         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 649
 650         return 0;
 651 }
 652
 653 static const size_t cta_min[CTA_MAX] = {
 654         [CTA_STATUS-1]          = sizeof(u_int32_t),
 655         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 656         [CTA_MARK-1]            = sizeof(u_int32_t),
 657         [CTA_USE-1]             = sizeof(u_int32_t),
 658         [CTA_ID-1]              = sizeof(u_int32_t)
 659 };
 660
 661 static int
 662 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 663                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 664 {
 665         struct nf_conntrack_tuple_hash *h;
 666         struct nf_conntrack_tuple tuple;
 667         struct nf_conn *ct;
 668         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 669         u_int8_t u3 = nfmsg->nfgen_family;
 670         int err = 0;
 671
 672         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 673                 return -EINVAL;
 674
 675         if (cda[CTA_TUPLE_ORIG-1])
 676                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 677         else if (cda[CTA_TUPLE_REPLY-1])
 678                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 679         else {
 680                 /* Flush the whole table */
 681                 nf_conntrack_flush();
 682                 return 0;
 683         }
 684
 685         if (err < 0)
 686                 return err;
 687
 688         h = nf_conntrack_find_get(&tuple, NULL);
 689         if (!h)
 690                 return -ENOENT;
 691
 692         ct = nf_ct_tuplehash_to_ctrack(h);
 693
 694         if (cda[CTA_ID-1]) {
 695                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
 696                 if (ct->id != id) {
 697                         nf_ct_put(ct);
 698                         return -ENOENT;
 699                 }
 700         }
 701         if (del_timer(&ct->timeout))
 702                 ct->timeout.function((unsigned long)ct);
 703
 704         nf_ct_put(ct);
 705
 706         return 0;
 707 }
 708
 709 static int
 710 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 711                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 712 {
 713         struct nf_conntrack_tuple_hash *h;
 714         struct nf_conntrack_tuple tuple;
 715         struct nf_conn *ct;
 716         struct sk_buff *skb2 = NULL;
 717         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 718         u_int8_t u3 = nfmsg->nfgen_family;
 719         int err = 0;
 720
 721         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 722                 u32 rlen;
 723
 724 #ifndef CONFIG_NF_CT_ACCT
 725                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
 726                         return -ENOTSUPP;
 727 #endif
 728                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 729                                                 ctnetlink_dump_table,
 730                                                 ctnetlink_done)) != 0)
 731                         return -EINVAL;
 732
 733                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 734                 if (rlen > skb->len)
 735                         rlen = skb->len;
 736                 skb_pull(skb, rlen);
 737                 return 0;
 738         }
 739
 740         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 741                 return -EINVAL;
 742
 743         if (cda[CTA_TUPLE_ORIG-1])
 744                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 745         else if (cda[CTA_TUPLE_REPLY-1])
 746                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 747         else
 748                 return -EINVAL;
 749
 750         if (err < 0)
 751                 return err;
 752
 753         h = nf_conntrack_find_get(&tuple, NULL);
 754         if (!h)
 755                 return -ENOENT;
 756
 757         ct = nf_ct_tuplehash_to_ctrack(h);
 758
 759         err = -ENOMEM;
 760         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 761         if (!skb2) {
 762                 nf_ct_put(ct);
 763                 return -ENOMEM;
 764         }
 765
 766         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 767                                   IPCTNL_MSG_CT_NEW, 1, ct);
 768         nf_ct_put(ct);
 769         if (err <= 0)
 770                 goto free;
 771
 772         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 773         if (err < 0)
 774                 goto out;
 775
 776         return 0;
 777
 778 free:
 779         kfree_skb(skb2);
 780 out:
 781         return err;
 782 }
 783
 784 static inline int
 785 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 786 {
 787         unsigned long d;
 788         unsigned int status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));
 789         d = ct->status ^ status;
 790
 791         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 792                 /* unchangeable */
 793                 return -EINVAL;
 794
 795         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 796                 /* SEEN_REPLY bit can only be set */
 797                 return -EINVAL;
 798
 799
 800         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 801                 /* ASSURED bit can only be set */
 802                 return -EINVAL;
 803
 804         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 805 #ifndef CONFIG_NF_NAT_NEEDED
 806                 return -EINVAL;
 807 #else
 808                 struct nf_nat_range range;
 809
 810                 if (cda[CTA_NAT_DST-1]) {
 811                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 812                                                 &range) < 0)
 813                                 return -EINVAL;
 814                         if (nf_nat_initialized(ct,
 815                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 816                                 return -EEXIST;
 817                         nf_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
 818                 }
 819                 if (cda[CTA_NAT_SRC-1]) {
 820                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 821                                                 &range) < 0)
 822                                 return -EINVAL;
 823                         if (nf_nat_initialized(ct,
 824                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 825                                 return -EEXIST;
 826                         nf_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
 827                 }
 828 #endif
 829         }
 830
 831         /* Be careful here, modifying NAT bits can screw up things,
 832          * so don't let users modify them directly if they don't pass
 833          * nf_nat_range. */
 834         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 835         return 0;
 836 }
 837
 838
 839 static inline int
 840 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 841 {
 842         struct nf_conntrack_helper *helper;
 843         struct nf_conn_help *help = nfct_help(ct);
 844         char *helpname;
 845         int err;
 846
 847         if (!help) {
 848                 /* FIXME: we need to reallocate and rehash */
 849                 return -EBUSY;
 850         }
 851
 852         /* don't change helper of sibling connections */
 853         if (ct->master)
 854                 return -EINVAL;
 855
 856         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 857         if (err < 0)
 858                 return err;
 859
 860         helper = __nf_conntrack_helper_find_byname(helpname);
 861         if (!helper) {
 862                 if (!strcmp(helpname, ""))
 863                         helper = NULL;
 864                 else
 865                         return -EINVAL;
 866         }
 867
 868         if (help->helper) {
 869                 if (!helper) {
 870                         /* we had a helper before ... */
 871                         nf_ct_remove_expectations(ct);
 872                         help->helper = NULL;
 873                 } else {
 874                         /* need to zero data of old helper */
 875                         memset(&help->help, 0, sizeof(help->help));
 876                 }
 877         }
 878
 879         help->helper = helper;
 880
 881         return 0;
 882 }
 883
 884 static inline int
 885 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 886 {
 887         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 888
 889         if (!del_timer(&ct->timeout))
 890                 return -ETIME;
 891
 892         ct->timeout.expires = jiffies + timeout * HZ;
 893         add_timer(&ct->timeout);
 894
 895         return 0;
 896 }
 897
 898 static inline int
 899 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 900 {
 901         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 902         struct nf_conntrack_l4proto *l4proto;
 903         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 904         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 905         int err = 0;
 906
 907         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 908
 909         l4proto = nf_ct_l4proto_find_get(l3num, npt);
 910
 911         if (l4proto->from_nfattr)
 912                 err = l4proto->from_nfattr(tb, ct);
 913         nf_ct_l4proto_put(l4proto);
 914
 915         return err;
 916 }
 917
 918 static int
 919 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
 920 {
 921         int err;
 922
 923         if (cda[CTA_HELP-1]) {
 924                 err = ctnetlink_change_helper(ct, cda);
 925                 if (err < 0)
 926                         return err;
 927         }
 928
 929         if (cda[CTA_TIMEOUT-1]) {
 930                 err = ctnetlink_change_timeout(ct, cda);
 931                 if (err < 0)
 932                         return err;
 933         }
 934
 935         if (cda[CTA_STATUS-1]) {
 936                 err = ctnetlink_change_status(ct, cda);
 937                 if (err < 0)
 938                         return err;
 939         }
 940
 941         if (cda[CTA_PROTOINFO-1]) {
 942                 err = ctnetlink_change_protoinfo(ct, cda);
 943                 if (err < 0)
 944                         return err;
 945         }
 946
 947 #if defined(CONFIG_NF_CONNTRACK_MARK)
 948         if (cda[CTA_MARK-1])
 949                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 950 #endif
 951
 952         return 0;
 953 }
 954
 955 static int
 956 ctnetlink_create_conntrack(struct nfattr *cda[],
 957                            struct nf_conntrack_tuple *otuple,
 958                            struct nf_conntrack_tuple *rtuple)
 959 {
 960         struct nf_conn *ct;
 961         int err = -EINVAL;
 962         struct nf_conn_help *help;
 963
 964         ct = nf_conntrack_alloc(otuple, rtuple);
 965         if (ct == NULL || IS_ERR(ct))
 966                 return -ENOMEM;
 967
 968         if (!cda[CTA_TIMEOUT-1])
 969                 goto err;
 970         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 971
 972         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
 973         ct->status |= IPS_CONFIRMED;
 974
 975         if (cda[CTA_STATUS-1]) {
 976                 err = ctnetlink_change_status(ct, cda);
 977                 if (err < 0)
 978                         goto err;
 979         }
 980
 981         if (cda[CTA_PROTOINFO-1]) {
 982                 err = ctnetlink_change_protoinfo(ct, cda);
 983                 if (err < 0)
 984                         goto err;
 985         }
 986
 987 #if defined(CONFIG_NF_CONNTRACK_MARK)
 988         if (cda[CTA_MARK-1])
 989                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 990 #endif
 991
 992         help = nfct_help(ct);
 993         if (help)
 994                 help->helper = nf_ct_helper_find_get(rtuple);
 995
 996         add_timer(&ct->timeout);
 997         nf_conntrack_hash_insert(ct);
 998
 999         if (help && help->helper)
1000                 nf_ct_helper_put(help->helper);
1001
1002         return 0;
1003
1004 err:
1005         nf_conntrack_free(ct);
1006         return err;
1007 }
1008
1009 static int
1010 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1011                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1012 {
1013         struct nf_conntrack_tuple otuple, rtuple;
1014         struct nf_conntrack_tuple_hash *h = NULL;
1015         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1016         u_int8_t u3 = nfmsg->nfgen_family;
1017         int err = 0;
1018
1019         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1020                 return -EINVAL;
1021
1022         if (cda[CTA_TUPLE_ORIG-1]) {
1023                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1024                 if (err < 0)
1025                         return err;
1026         }
1027
1028         if (cda[CTA_TUPLE_REPLY-1]) {
1029                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1030                 if (err < 0)
1031                         return err;
1032         }
1033
1034         write_lock_bh(&nf_conntrack_lock);
1035         if (cda[CTA_TUPLE_ORIG-1])
1036                 h = __nf_conntrack_find(&otuple, NULL);
1037         else if (cda[CTA_TUPLE_REPLY-1])
1038                 h = __nf_conntrack_find(&rtuple, NULL);
1039
1040         if (h == NULL) {
1041                 write_unlock_bh(&nf_conntrack_lock);
1042                 err = -ENOENT;
1043                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1044                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1045                 return err;
1046         }
1047         /* implicit 'else' */
1048
1049         /* we only allow nat config for new conntracks */
1050         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1051                 err = -EINVAL;
1052                 goto out_unlock;
1053         }
1054
1055         /* We manipulate the conntrack inside the global conntrack table lock,
1056          * so there's no need to increase the refcount */
1057         err = -EEXIST;
1058         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1059                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1060
1061 out_unlock:
1062         write_unlock_bh(&nf_conntrack_lock);
1063         return err;
1064 }
1065
1066 /***********************************************************************
1067  * EXPECT
1068  ***********************************************************************/
1069
1070 static inline int
1071 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1072                          const struct nf_conntrack_tuple *tuple,
1073                          enum ctattr_expect type)
1074 {
1075         struct nfattr *nest_parms = NFA_NEST(skb, type);
1076
1077         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1078                 goto nfattr_failure;
1079
1080         NFA_NEST_END(skb, nest_parms);
1081
1082         return 0;
1083
1084 nfattr_failure:
1085         return -1;
1086 }
1087
1088 static inline int
1089 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1090                         const struct nf_conntrack_tuple *tuple,
1091                         const struct nf_conntrack_tuple *mask)
1092 {
1093         int ret;
1094         struct nf_conntrack_l3proto *l3proto;
1095         struct nf_conntrack_l4proto *l4proto;
1096         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1097
1098         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1099         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1100         nf_ct_l3proto_put(l3proto);
1101
1102         if (unlikely(ret < 0))
1103                 goto nfattr_failure;
1104
1105         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1106         ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);
1107         nf_ct_l4proto_put(l4proto);
1108         if (unlikely(ret < 0))
1109                 goto nfattr_failure;
1110
1111         NFA_NEST_END(skb, nest_parms);
1112
1113         return 0;
1114
1115 nfattr_failure:
1116         return -1;
1117 }
1118
1119 static inline int
1120 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1121                           const struct nf_conntrack_expect *exp)
1122 {
1123         struct nf_conn *master = exp->master;
1124         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1125         __be32 id = htonl(exp->id);
1126
1127         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1128                 goto nfattr_failure;
1129         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1130                 goto nfattr_failure;
1131         if (ctnetlink_exp_dump_tuple(skb,
1132                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1133                                  CTA_EXPECT_MASTER) < 0)
1134                 goto nfattr_failure;
1135
1136         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1137         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1138
1139         return 0;
1140
1141 nfattr_failure:
1142         return -1;
1143 }
1144
1145 static int
1146 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1147                     int event,
1148                     int nowait,
1149                     const struct nf_conntrack_expect *exp)
1150 {
1151         struct nlmsghdr *nlh;
1152         struct nfgenmsg *nfmsg;
1153         unsigned char *b = skb_tail_pointer(skb);
1154
1155         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1156         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1157         nfmsg  = NLMSG_DATA(nlh);
1158
1159         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1160         nfmsg->nfgen_family = exp->tuple.src.l3num;
1161         nfmsg->version      = NFNETLINK_V0;
1162         nfmsg->res_id       = 0;
1163
1164         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1165                 goto nfattr_failure;
1166
1167         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1168         return skb->len;
1169
1170 nlmsg_failure:
1171 nfattr_failure:
1172         skb_trim(skb, b - skb->data);
1173         return -1;
1174 }
1175
1176 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1177 static int ctnetlink_expect_event(struct notifier_block *this,
1178                                   unsigned long events, void *ptr)
1179 {
1180         struct nlmsghdr *nlh;
1181         struct nfgenmsg *nfmsg;
1182         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1183         struct sk_buff *skb;
1184         unsigned int type;
1185         sk_buff_data_t b;
1186         int flags = 0;
1187
1188         if (events & IPEXP_NEW) {
1189                 type = IPCTNL_MSG_EXP_NEW;
1190                 flags = NLM_F_CREATE|NLM_F_EXCL;
1191         } else
1192                 return NOTIFY_DONE;
1193
1194         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1195                 return NOTIFY_DONE;
1196
1197         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1198         if (!skb)
1199                 return NOTIFY_DONE;
1200
1201         b = skb->tail;
1202
1203         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1204         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1205         nfmsg = NLMSG_DATA(nlh);
1206
1207         nlh->nlmsg_flags    = flags;
1208         nfmsg->nfgen_family = exp->tuple.src.l3num;
1209         nfmsg->version      = NFNETLINK_V0;
1210         nfmsg->res_id       = 0;
1211
1212         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1213                 goto nfattr_failure;
1214
1215         nlh->nlmsg_len = skb->tail - b;
1216         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1217         return NOTIFY_DONE;
1218
1219 nlmsg_failure:
1220 nfattr_failure:
1221         kfree_skb(skb);
1222         return NOTIFY_DONE;
1223 }
1224 #endif
1225
1226 static int
1227 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1228 {
1229         struct nf_conntrack_expect *exp = NULL;
1230         struct list_head *i;
1231         u_int32_t *id = (u_int32_t *) &cb->args[0];
1232         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1233         u_int8_t l3proto = nfmsg->nfgen_family;
1234
1235         read_lock_bh(&nf_conntrack_lock);
1236         list_for_each_prev(i, &nf_conntrack_expect_list) {
1237                 exp = (struct nf_conntrack_expect *) i;
1238                 if (l3proto && exp->tuple.src.l3num != l3proto)
1239                         continue;
1240                 if (exp->id <= *id)
1241                         continue;
1242                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1243                                             cb->nlh->nlmsg_seq,
1244                                             IPCTNL_MSG_EXP_NEW,
1245                                             1, exp) < 0)
1246                         goto out;
1247                 *id = exp->id;
1248         }
1249 out:
1250         read_unlock_bh(&nf_conntrack_lock);
1251
1252         return skb->len;
1253 }
1254
1255 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1256         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1257         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1258 };
1259
1260 static int
1261 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1262                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1263 {
1264         struct nf_conntrack_tuple tuple;
1265         struct nf_conntrack_expect *exp;
1266         struct sk_buff *skb2;
1267         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1268         u_int8_t u3 = nfmsg->nfgen_family;
1269         int err = 0;
1270
1271         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1272                 return -EINVAL;
1273
1274         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1275                 u32 rlen;
1276
1277                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1278                                                 ctnetlink_exp_dump_table,
1279                                                 ctnetlink_done)) != 0)
1280                         return -EINVAL;
1281                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1282                 if (rlen > skb->len)
1283                         rlen = skb->len;
1284                 skb_pull(skb, rlen);
1285                 return 0;
1286         }
1287
1288         if (cda[CTA_EXPECT_MASTER-1])
1289                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1290         else
1291                 return -EINVAL;
1292
1293         if (err < 0)
1294                 return err;
1295
1296         exp = nf_conntrack_expect_find_get(&tuple);
1297         if (!exp)
1298                 return -ENOENT;
1299
1300         if (cda[CTA_EXPECT_ID-1]) {
1301                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1302                 if (exp->id != ntohl(id)) {
1303                         nf_conntrack_expect_put(exp);
1304                         return -ENOENT;
1305                 }
1306         }
1307
1308         err = -ENOMEM;
1309         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1310         if (!skb2)
1311                 goto out;
1312
1313         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1314                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1315                                       1, exp);
1316         if (err <= 0)
1317                 goto free;
1318
1319         nf_conntrack_expect_put(exp);
1320
1321         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1322
1323 free:
1324         kfree_skb(skb2);
1325 out:
1326         nf_conntrack_expect_put(exp);
1327         return err;
1328 }
1329
1330 static int
1331 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1332                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1333 {
1334         struct nf_conntrack_expect *exp, *tmp;
1335         struct nf_conntrack_tuple tuple;
1336         struct nf_conntrack_helper *h;
1337         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1338         u_int8_t u3 = nfmsg->nfgen_family;
1339         int err;
1340
1341         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1342                 return -EINVAL;
1343
1344         if (cda[CTA_EXPECT_TUPLE-1]) {
1345                 /* delete a single expect by tuple */
1346                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1347                 if (err < 0)
1348                         return err;
1349
1350                 /* bump usage count to 2 */
1351                 exp = nf_conntrack_expect_find_get(&tuple);
1352                 if (!exp)
1353                         return -ENOENT;
1354
1355                 if (cda[CTA_EXPECT_ID-1]) {
1356                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1357                         if (exp->id != ntohl(id)) {
1358                                 nf_conntrack_expect_put(exp);
1359                                 return -ENOENT;
1360                         }
1361                 }
1362
1363                 /* after list removal, usage count == 1 */
1364                 nf_conntrack_unexpect_related(exp);
1365                 /* have to put what we 'get' above.
1366                  * after this line usage count == 0 */
1367                 nf_conntrack_expect_put(exp);
1368         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1369                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1370
1371                 /* delete all expectations for this helper */
1372                 write_lock_bh(&nf_conntrack_lock);
1373                 h = __nf_conntrack_helper_find_byname(name);
1374                 if (!h) {
1375                         write_unlock_bh(&nf_conntrack_lock);
1376                         return -EINVAL;
1377                 }
1378                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1379                                          list) {
1380                         struct nf_conn_help *m_help = nfct_help(exp->master);
1381                         if (m_help->helper == h
1382                             && del_timer(&exp->timeout)) {
1383                                 nf_ct_unlink_expect(exp);
1384                                 nf_conntrack_expect_put(exp);
1385                         }
1386                 }
1387                 write_unlock_bh(&nf_conntrack_lock);
1388         } else {
1389                 /* This basically means we have to flush everything*/
1390                 write_lock_bh(&nf_conntrack_lock);
1391                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1392                                          list) {
1393                         if (del_timer(&exp->timeout)) {
1394                                 nf_ct_unlink_expect(exp);
1395                                 nf_conntrack_expect_put(exp);
1396                         }
1397                 }
1398                 write_unlock_bh(&nf_conntrack_lock);
1399         }
1400
1401         return 0;
1402 }
1403 static int
1404 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1405 {
1406         return -EOPNOTSUPP;
1407 }
1408
1409 static int
1410 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1411 {
1412         struct nf_conntrack_tuple tuple, mask, master_tuple;
1413         struct nf_conntrack_tuple_hash *h = NULL;
1414         struct nf_conntrack_expect *exp;
1415         struct nf_conn *ct;
1416         struct nf_conn_help *help;
1417         int err = 0;
1418
1419         /* caller guarantees that those three CTA_EXPECT_* exist */
1420         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1421         if (err < 0)
1422                 return err;
1423         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1424         if (err < 0)
1425                 return err;
1426         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1427         if (err < 0)
1428                 return err;
1429
1430         /* Look for master conntrack of this expectation */
1431         h = nf_conntrack_find_get(&master_tuple, NULL);
1432         if (!h)
1433                 return -ENOENT;
1434         ct = nf_ct_tuplehash_to_ctrack(h);
1435         help = nfct_help(ct);
1436
1437         if (!help || !help->helper) {
1438                 /* such conntrack hasn't got any helper, abort */
1439                 err = -EINVAL;
1440                 goto out;
1441         }
1442
1443         exp = nf_conntrack_expect_alloc(ct);
1444         if (!exp) {
1445                 err = -ENOMEM;
1446                 goto out;
1447         }
1448
1449         exp->expectfn = NULL;
1450         exp->flags = 0;
1451         exp->master = ct;
1452         exp->helper = NULL;
1453         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1454         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1455
1456         err = nf_conntrack_expect_related(exp);
1457         nf_conntrack_expect_put(exp);
1458
1459 out:
1460         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1461         return err;
1462 }
1463
1464 static int
1465 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1466                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1467 {
1468         struct nf_conntrack_tuple tuple;
1469         struct nf_conntrack_expect *exp;
1470         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1471         u_int8_t u3 = nfmsg->nfgen_family;
1472         int err = 0;
1473
1474         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1475                 return -EINVAL;
1476
1477         if (!cda[CTA_EXPECT_TUPLE-1]
1478             || !cda[CTA_EXPECT_MASK-1]
1479             || !cda[CTA_EXPECT_MASTER-1])
1480                 return -EINVAL;
1481
1482         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1483         if (err < 0)
1484                 return err;
1485
1486         write_lock_bh(&nf_conntrack_lock);
1487         exp = __nf_conntrack_expect_find(&tuple);
1488
1489         if (!exp) {
1490                 write_unlock_bh(&nf_conntrack_lock);
1491                 err = -ENOENT;
1492                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1493                         err = ctnetlink_create_expect(cda, u3);
1494                 return err;
1495         }
1496
1497         err = -EEXIST;
1498         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1499                 err = ctnetlink_change_expect(exp, cda);
1500         write_unlock_bh(&nf_conntrack_lock);
1501
1502         return err;
1503 }
1504
1505 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1506 static struct notifier_block ctnl_notifier = {
1507         .notifier_call  = ctnetlink_conntrack_event,
1508 };
1509
1510 static struct notifier_block ctnl_notifier_exp = {
1511         .notifier_call  = ctnetlink_expect_event,
1512 };
1513 #endif
1514
1515 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1516         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1517                                             .attr_count = CTA_MAX, },
1518         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1519                                             .attr_count = CTA_MAX, },
1520         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1521                                             .attr_count = CTA_MAX, },
1522         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1523                                             .attr_count = CTA_MAX, },
1524 };
1525
1526 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1527         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1528                                             .attr_count = CTA_EXPECT_MAX, },
1529         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1530                                             .attr_count = CTA_EXPECT_MAX, },
1531         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1532                                             .attr_count = CTA_EXPECT_MAX, },
1533 };
1534
1535 static struct nfnetlink_subsystem ctnl_subsys = {
1536         .name                           = "conntrack",
1537         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1538         .cb_count                       = IPCTNL_MSG_MAX,
1539         .cb                             = ctnl_cb,
1540 };
1541
1542 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1543         .name                           = "conntrack_expect",
1544         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1545         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1546         .cb                             = ctnl_exp_cb,
1547 };
1548
1549 MODULE_ALIAS("ip_conntrack_netlink");
1550 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1551 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1552
1553 static int __init ctnetlink_init(void)
1554 {
1555         int ret;
1556
1557         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1558         ret = nfnetlink_subsys_register(&ctnl_subsys);
1559         if (ret < 0) {
1560                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1561                 goto err_out;
1562         }
1563
1564         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1565         if (ret < 0) {
1566                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1567                 goto err_unreg_subsys;
1568         }
1569
1570 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1571         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1572         if (ret < 0) {
1573                 printk("ctnetlink_init: cannot register notifier.\n");
1574                 goto err_unreg_exp_subsys;
1575         }
1576
1577         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1578         if (ret < 0) {
1579                 printk("ctnetlink_init: cannot expect register notifier.\n");
1580                 goto err_unreg_notifier;
1581         }
1582 #endif
1583
1584         return 0;
1585
1586 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1587 err_unreg_notifier:
1588         nf_conntrack_unregister_notifier(&ctnl_notifier);
1589 err_unreg_exp_subsys:
1590         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1591 #endif
1592 err_unreg_subsys:
1593         nfnetlink_subsys_unregister(&ctnl_subsys);
1594 err_out:
1595         return ret;
1596 }
1597
1598 static void __exit ctnetlink_exit(void)
1599 {
1600         printk("ctnetlink: unregistering from nfnetlink.\n");
1601
1602 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1603         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1604         nf_conntrack_unregister_notifier(&ctnl_notifier);
1605 #endif
1606
1607         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1608         nfnetlink_subsys_unregister(&ctnl_subsys);
1609         return;
1610 }
1611
1612 module_init(ctnetlink_init);
1613 module_exit(ctnetlink_exit);