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;
 272
 273         b = skb->tail;
 274
 275         event |= NFNL_SUBSYS_CTNETLINK << 8;
 276         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 277         nfmsg  = NLMSG_DATA(nlh);
 278
 279         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 280         nfmsg->nfgen_family =
 281                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 282         nfmsg->version      = NFNETLINK_V0;
 283         nfmsg->res_id       = 0;
 284
 285         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 286         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 287                 goto nfattr_failure;
 288         NFA_NEST_END(skb, nest_parms);
 289
 290         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 291         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 292                 goto nfattr_failure;
 293         NFA_NEST_END(skb, nest_parms);
 294
 295         if (ctnetlink_dump_status(skb, ct) < 0 ||
 296             ctnetlink_dump_timeout(skb, ct) < 0 ||
 297             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 298             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 299             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 300             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 301             ctnetlink_dump_mark(skb, ct) < 0 ||
 302             ctnetlink_dump_id(skb, ct) < 0 ||
 303             ctnetlink_dump_use(skb, ct) < 0)
 304                 goto nfattr_failure;
 305
 306         nlh->nlmsg_len = skb->tail - b;
 307         return skb->len;
 308
 309 nlmsg_failure:
 310 nfattr_failure:
 311         skb_trim(skb, b - skb->data);
 312         return -1;
 313 }
 314
 315 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 316 static int ctnetlink_conntrack_event(struct notifier_block *this,
 317                                      unsigned long events, void *ptr)
 318 {
 319         struct nlmsghdr *nlh;
 320         struct nfgenmsg *nfmsg;
 321         struct nfattr *nest_parms;
 322         struct nf_conn *ct = (struct nf_conn *)ptr;
 323         struct sk_buff *skb;
 324         unsigned int type;
 325         unsigned char *b;
 326         unsigned int flags = 0, group;
 327
 328         /* ignore our fake conntrack entry */
 329         if (ct == &nf_conntrack_untracked)
 330                 return NOTIFY_DONE;
 331
 332         if (events & IPCT_DESTROY) {
 333                 type = IPCTNL_MSG_CT_DELETE;
 334                 group = NFNLGRP_CONNTRACK_DESTROY;
 335         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 336                 type = IPCTNL_MSG_CT_NEW;
 337                 flags = NLM_F_CREATE|NLM_F_EXCL;
 338                 group = NFNLGRP_CONNTRACK_NEW;
 339         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 340                 type = IPCTNL_MSG_CT_NEW;
 341                 group = NFNLGRP_CONNTRACK_UPDATE;
 342         } else
 343                 return NOTIFY_DONE;
 344
 345         if (!nfnetlink_has_listeners(group))
 346                 return NOTIFY_DONE;
 347
 348         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 349         if (!skb)
 350                 return NOTIFY_DONE;
 351
 352         b = skb->tail;
 353
 354         type |= NFNL_SUBSYS_CTNETLINK << 8;
 355         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 356         nfmsg = NLMSG_DATA(nlh);
 357
 358         nlh->nlmsg_flags    = flags;
 359         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 360         nfmsg->version  = NFNETLINK_V0;
 361         nfmsg->res_id   = 0;
 362
 363         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 364         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 365                 goto nfattr_failure;
 366         NFA_NEST_END(skb, nest_parms);
 367
 368         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 369         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 370                 goto nfattr_failure;
 371         NFA_NEST_END(skb, nest_parms);
 372
 373         if (events & IPCT_DESTROY) {
 374                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 375                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 376                         goto nfattr_failure;
 377         } else {
 378                 if (ctnetlink_dump_status(skb, ct) < 0)
 379                         goto nfattr_failure;
 380
 381                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 382                         goto nfattr_failure;
 383
 384                 if (events & IPCT_PROTOINFO
 385                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 386                         goto nfattr_failure;
 387
 388                 if ((events & IPCT_HELPER || nfct_help(ct))
 389                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 390                         goto nfattr_failure;
 391
 392 #ifdef CONFIG_NF_CONNTRACK_MARK
 393                 if ((events & IPCT_MARK || ct->mark)
 394                     && ctnetlink_dump_mark(skb, ct) < 0)
 395                         goto nfattr_failure;
 396 #endif
 397
 398                 if (events & IPCT_COUNTER_FILLING &&
 399                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 400                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
 401                         goto nfattr_failure;
 402         }
 403
 404         nlh->nlmsg_len = skb->tail - b;
 405         nfnetlink_send(skb, 0, group, 0);
 406         return NOTIFY_DONE;
 407
 408 nlmsg_failure:
 409 nfattr_failure:
 410         kfree_skb(skb);
 411         return NOTIFY_DONE;
 412 }
 413 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 414
 415 static int ctnetlink_done(struct netlink_callback *cb)
 416 {
 417         if (cb->args[1])
 418                 nf_ct_put((struct nf_conn *)cb->args[1]);
 419         return 0;
 420 }
 421
 422 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 423
 424 static int
 425 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 426 {
 427         struct nf_conn *ct, *last;
 428         struct nf_conntrack_tuple_hash *h;
 429         struct list_head *i;
 430         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 431         u_int8_t l3proto = nfmsg->nfgen_family;
 432
 433         read_lock_bh(&nf_conntrack_lock);
 434         last = (struct nf_conn *)cb->args[1];
 435         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
 436 restart:
 437                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 438                         h = (struct nf_conntrack_tuple_hash *) i;
 439                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 440                                 continue;
 441                         ct = nf_ct_tuplehash_to_ctrack(h);
 442                         /* Dump entries of a given L3 protocol number.
 443                          * If it is not specified, ie. l3proto == 0,
 444                          * then dump everything. */
 445                         if (l3proto && L3PROTO(ct) != l3proto)
 446                                 continue;
 447                         if (cb->args[1]) {
 448                                 if (ct != last)
 449                                         continue;
 450                                 cb->args[1] = 0;
 451                         }
 452                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 453                                                 cb->nlh->nlmsg_seq,
 454                                                 IPCTNL_MSG_CT_NEW,
 455                                                 1, ct) < 0) {
 456                                 nf_conntrack_get(&ct->ct_general);
 457                                 cb->args[1] = (unsigned long)ct;
 458                                 goto out;
 459                         }
 460 #ifdef CONFIG_NF_CT_ACCT
 461                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 462                                                 IPCTNL_MSG_CT_GET_CTRZERO)
 463                                 memset(&ct->counters, 0, sizeof(ct->counters));
 464 #endif
 465                 }
 466                 if (cb->args[1]) {
 467                         cb->args[1] = 0;
 468                         goto restart;
 469                 }
 470         }
 471 out:
 472         read_unlock_bh(&nf_conntrack_lock);
 473         if (last)
 474                 nf_ct_put(last);
 475
 476         return skb->len;
 477 }
 478
 479 static inline int
 480 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 481 {
 482         struct nfattr *tb[CTA_IP_MAX];
 483         struct nf_conntrack_l3proto *l3proto;
 484         int ret = 0;
 485
 486         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 487
 488         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 489
 490         if (likely(l3proto->nfattr_to_tuple))
 491                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 492
 493         nf_ct_l3proto_put(l3proto);
 494
 495         return ret;
 496 }
 497
 498 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 499         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 500 };
 501
 502 static inline int
 503 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 504                             struct nf_conntrack_tuple *tuple)
 505 {
 506         struct nfattr *tb[CTA_PROTO_MAX];
 507         struct nf_conntrack_l4proto *l4proto;
 508         int ret = 0;
 509
 510         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 511
 512         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 513                 return -EINVAL;
 514
 515         if (!tb[CTA_PROTO_NUM-1])
 516                 return -EINVAL;
 517         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 518
 519         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 520
 521         if (likely(l4proto->nfattr_to_tuple))
 522                 ret = l4proto->nfattr_to_tuple(tb, tuple);
 523
 524         nf_ct_l4proto_put(l4proto);
 525
 526         return ret;
 527 }
 528
 529 static inline int
 530 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 531                       enum ctattr_tuple type, u_int8_t l3num)
 532 {
 533         struct nfattr *tb[CTA_TUPLE_MAX];
 534         int err;
 535
 536         memset(tuple, 0, sizeof(*tuple));
 537
 538         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 539
 540         if (!tb[CTA_TUPLE_IP-1])
 541                 return -EINVAL;
 542
 543         tuple->src.l3num = l3num;
 544
 545         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 546         if (err < 0)
 547                 return err;
 548
 549         if (!tb[CTA_TUPLE_PROTO-1])
 550                 return -EINVAL;
 551
 552         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 553         if (err < 0)
 554                 return err;
 555
 556         /* orig and expect tuples get DIR_ORIGINAL */
 557         if (type == CTA_TUPLE_REPLY)
 558                 tuple->dst.dir = IP_CT_DIR_REPLY;
 559         else
 560                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 561
 562         return 0;
 563 }
 564
 565 #ifdef CONFIG_NF_NAT_NEEDED
 566 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 567         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 568         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 569 };
 570
 571 static int nfnetlink_parse_nat_proto(struct nfattr *attr,
 572                                      const struct nf_conn *ct,
 573                                      struct nf_nat_range *range)
 574 {
 575         struct nfattr *tb[CTA_PROTONAT_MAX];
 576         struct nf_nat_protocol *npt;
 577
 578         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 579
 580         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 581                 return -EINVAL;
 582
 583         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 584
 585         if (!npt->nfattr_to_range) {
 586                 nf_nat_proto_put(npt);
 587                 return 0;
 588         }
 589
 590         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 591         if (npt->nfattr_to_range(tb, range) > 0)
 592                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 593
 594         nf_nat_proto_put(npt);
 595
 596         return 0;
 597 }
 598
 599 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 600         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 601         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 602 };
 603
 604 static inline int
 605 nfnetlink_parse_nat(struct nfattr *nat,
 606                     const struct nf_conn *ct, struct nf_nat_range *range)
 607 {
 608         struct nfattr *tb[CTA_NAT_MAX];
 609         int err;
 610
 611         memset(range, 0, sizeof(*range));
 612
 613         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 614
 615         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 616                 return -EINVAL;
 617
 618         if (tb[CTA_NAT_MINIP-1])
 619                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 620
 621         if (!tb[CTA_NAT_MAXIP-1])
 622                 range->max_ip = range->min_ip;
 623         else
 624                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 625
 626         if (range->min_ip)
 627                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 628
 629         if (!tb[CTA_NAT_PROTO-1])
 630                 return 0;
 631
 632         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 633         if (err < 0)
 634                 return err;
 635
 636         return 0;
 637 }
 638 #endif
 639
 640 static inline int
 641 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 642 {
 643         struct nfattr *tb[CTA_HELP_MAX];
 644
 645         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 646
 647         if (!tb[CTA_HELP_NAME-1])
 648                 return -EINVAL;
 649
 650         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 651
 652         return 0;
 653 }
 654
 655 static const size_t cta_min[CTA_MAX] = {
 656         [CTA_STATUS-1]          = sizeof(u_int32_t),
 657         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 658         [CTA_MARK-1]            = sizeof(u_int32_t),
 659         [CTA_USE-1]             = sizeof(u_int32_t),
 660         [CTA_ID-1]              = sizeof(u_int32_t)
 661 };
 662
 663 static int
 664 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 665                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 666 {
 667         struct nf_conntrack_tuple_hash *h;
 668         struct nf_conntrack_tuple tuple;
 669         struct nf_conn *ct;
 670         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 671         u_int8_t u3 = nfmsg->nfgen_family;
 672         int err = 0;
 673
 674         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 675                 return -EINVAL;
 676
 677         if (cda[CTA_TUPLE_ORIG-1])
 678                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 679         else if (cda[CTA_TUPLE_REPLY-1])
 680                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 681         else {
 682                 /* Flush the whole table */
 683                 nf_conntrack_flush();
 684                 return 0;
 685         }
 686
 687         if (err < 0)
 688                 return err;
 689
 690         h = nf_conntrack_find_get(&tuple, NULL);
 691         if (!h)
 692                 return -ENOENT;
 693
 694         ct = nf_ct_tuplehash_to_ctrack(h);
 695
 696         if (cda[CTA_ID-1]) {
 697                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
 698                 if (ct->id != id) {
 699                         nf_ct_put(ct);
 700                         return -ENOENT;
 701                 }
 702         }
 703         if (del_timer(&ct->timeout))
 704                 ct->timeout.function((unsigned long)ct);
 705
 706         nf_ct_put(ct);
 707
 708         return 0;
 709 }
 710
 711 static int
 712 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 713                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 714 {
 715         struct nf_conntrack_tuple_hash *h;
 716         struct nf_conntrack_tuple tuple;
 717         struct nf_conn *ct;
 718         struct sk_buff *skb2 = NULL;
 719         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 720         u_int8_t u3 = nfmsg->nfgen_family;
 721         int err = 0;
 722
 723         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 724                 u32 rlen;
 725
 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                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 731                                                 ctnetlink_dump_table,
 732                                                 ctnetlink_done)) != 0)
 733                         return -EINVAL;
 734
 735                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 736                 if (rlen > skb->len)
 737                         rlen = skb->len;
 738                 skb_pull(skb, rlen);
 739                 return 0;
 740         }
 741
 742         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 743                 return -EINVAL;
 744
 745         if (cda[CTA_TUPLE_ORIG-1])
 746                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 747         else if (cda[CTA_TUPLE_REPLY-1])
 748                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 749         else
 750                 return -EINVAL;
 751
 752         if (err < 0)
 753                 return err;
 754
 755         h = nf_conntrack_find_get(&tuple, NULL);
 756         if (!h)
 757                 return -ENOENT;
 758
 759         ct = nf_ct_tuplehash_to_ctrack(h);
 760
 761         err = -ENOMEM;
 762         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 763         if (!skb2) {
 764                 nf_ct_put(ct);
 765                 return -ENOMEM;
 766         }
 767
 768         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 769                                   IPCTNL_MSG_CT_NEW, 1, ct);
 770         nf_ct_put(ct);
 771         if (err <= 0)
 772                 goto free;
 773
 774         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 775         if (err < 0)
 776                 goto out;
 777
 778         return 0;
 779
 780 free:
 781         kfree_skb(skb2);
 782 out:
 783         return err;
 784 }
 785
 786 static inline int
 787 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 788 {
 789         unsigned long d;
 790         unsigned int status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));
 791         d = ct->status ^ status;
 792
 793         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 794                 /* unchangeable */
 795                 return -EINVAL;
 796
 797         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 798                 /* SEEN_REPLY bit can only be set */
 799                 return -EINVAL;
 800
 801
 802         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 803                 /* ASSURED bit can only be set */
 804                 return -EINVAL;
 805
 806         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 807 #ifndef CONFIG_NF_NAT_NEEDED
 808                 return -EINVAL;
 809 #else
 810                 struct nf_nat_range range;
 811
 812                 if (cda[CTA_NAT_DST-1]) {
 813                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 814                                                 &range) < 0)
 815                                 return -EINVAL;
 816                         if (nf_nat_initialized(ct,
 817                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 818                                 return -EEXIST;
 819                         nf_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
 820                 }
 821                 if (cda[CTA_NAT_SRC-1]) {
 822                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 823                                                 &range) < 0)
 824                                 return -EINVAL;
 825                         if (nf_nat_initialized(ct,
 826                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 827                                 return -EEXIST;
 828                         nf_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
 829                 }
 830 #endif
 831         }
 832
 833         /* Be careful here, modifying NAT bits can screw up things,
 834          * so don't let users modify them directly if they don't pass
 835          * nf_nat_range. */
 836         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 837         return 0;
 838 }
 839
 840
 841 static inline int
 842 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 843 {
 844         struct nf_conntrack_helper *helper;
 845         struct nf_conn_help *help = nfct_help(ct);
 846         char *helpname;
 847         int err;
 848
 849         if (!help) {
 850                 /* FIXME: we need to reallocate and rehash */
 851                 return -EBUSY;
 852         }
 853
 854         /* don't change helper of sibling connections */
 855         if (ct->master)
 856                 return -EINVAL;
 857
 858         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 859         if (err < 0)
 860                 return err;
 861
 862         helper = __nf_conntrack_helper_find_byname(helpname);
 863         if (!helper) {
 864                 if (!strcmp(helpname, ""))
 865                         helper = NULL;
 866                 else
 867                         return -EINVAL;
 868         }
 869
 870         if (help->helper) {
 871                 if (!helper) {
 872                         /* we had a helper before ... */
 873                         nf_ct_remove_expectations(ct);
 874                         help->helper = NULL;
 875                 } else {
 876                         /* need to zero data of old helper */
 877                         memset(&help->help, 0, sizeof(help->help));
 878                 }
 879         }
 880
 881         help->helper = helper;
 882
 883         return 0;
 884 }
 885
 886 static inline int
 887 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 888 {
 889         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 890
 891         if (!del_timer(&ct->timeout))
 892                 return -ETIME;
 893
 894         ct->timeout.expires = jiffies + timeout * HZ;
 895         add_timer(&ct->timeout);
 896
 897         return 0;
 898 }
 899
 900 static inline int
 901 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 902 {
 903         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 904         struct nf_conntrack_l4proto *l4proto;
 905         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 906         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 907         int err = 0;
 908
 909         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 910
 911         l4proto = nf_ct_l4proto_find_get(l3num, npt);
 912
 913         if (l4proto->from_nfattr)
 914                 err = l4proto->from_nfattr(tb, ct);
 915         nf_ct_l4proto_put(l4proto);
 916
 917         return err;
 918 }
 919
 920 static int
 921 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
 922 {
 923         int err;
 924
 925         if (cda[CTA_HELP-1]) {
 926                 err = ctnetlink_change_helper(ct, cda);
 927                 if (err < 0)
 928                         return err;
 929         }
 930
 931         if (cda[CTA_TIMEOUT-1]) {
 932                 err = ctnetlink_change_timeout(ct, cda);
 933                 if (err < 0)
 934                         return err;
 935         }
 936
 937         if (cda[CTA_STATUS-1]) {
 938                 err = ctnetlink_change_status(ct, cda);
 939                 if (err < 0)
 940                         return err;
 941         }
 942
 943         if (cda[CTA_PROTOINFO-1]) {
 944                 err = ctnetlink_change_protoinfo(ct, cda);
 945                 if (err < 0)
 946                         return err;
 947         }
 948
 949 #if defined(CONFIG_NF_CONNTRACK_MARK)
 950         if (cda[CTA_MARK-1])
 951                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 952 #endif
 953
 954         return 0;
 955 }
 956
 957 static int
 958 ctnetlink_create_conntrack(struct nfattr *cda[],
 959                            struct nf_conntrack_tuple *otuple,
 960                            struct nf_conntrack_tuple *rtuple)
 961 {
 962         struct nf_conn *ct;
 963         int err = -EINVAL;
 964         struct nf_conn_help *help;
 965
 966         ct = nf_conntrack_alloc(otuple, rtuple);
 967         if (ct == NULL || IS_ERR(ct))
 968                 return -ENOMEM;
 969
 970         if (!cda[CTA_TIMEOUT-1])
 971                 goto err;
 972         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 973
 974         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
 975         ct->status |= IPS_CONFIRMED;
 976
 977         if (cda[CTA_STATUS-1]) {
 978                 err = ctnetlink_change_status(ct, cda);
 979                 if (err < 0)
 980                         goto err;
 981         }
 982
 983         if (cda[CTA_PROTOINFO-1]) {
 984                 err = ctnetlink_change_protoinfo(ct, cda);
 985                 if (err < 0)
 986                         goto err;
 987         }
 988
 989 #if defined(CONFIG_NF_CONNTRACK_MARK)
 990         if (cda[CTA_MARK-1])
 991                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 992 #endif
 993
 994         help = nfct_help(ct);
 995         if (help)
 996                 help->helper = nf_ct_helper_find_get(rtuple);
 997
 998         add_timer(&ct->timeout);
 999         nf_conntrack_hash_insert(ct);
1000
1001         if (help && help->helper)
1002                 nf_ct_helper_put(help->helper);
1003
1004         return 0;
1005
1006 err:
1007         nf_conntrack_free(ct);
1008         return err;
1009 }
1010
1011 static int
1012 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1013                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1014 {
1015         struct nf_conntrack_tuple otuple, rtuple;
1016         struct nf_conntrack_tuple_hash *h = NULL;
1017         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1018         u_int8_t u3 = nfmsg->nfgen_family;
1019         int err = 0;
1020
1021         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1022                 return -EINVAL;
1023
1024         if (cda[CTA_TUPLE_ORIG-1]) {
1025                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1026                 if (err < 0)
1027                         return err;
1028         }
1029
1030         if (cda[CTA_TUPLE_REPLY-1]) {
1031                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1032                 if (err < 0)
1033                         return err;
1034         }
1035
1036         write_lock_bh(&nf_conntrack_lock);
1037         if (cda[CTA_TUPLE_ORIG-1])
1038                 h = __nf_conntrack_find(&otuple, NULL);
1039         else if (cda[CTA_TUPLE_REPLY-1])
1040                 h = __nf_conntrack_find(&rtuple, NULL);
1041
1042         if (h == NULL) {
1043                 write_unlock_bh(&nf_conntrack_lock);
1044                 err = -ENOENT;
1045                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1046                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1047                 return err;
1048         }
1049         /* implicit 'else' */
1050
1051         /* we only allow nat config for new conntracks */
1052         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1053                 err = -EINVAL;
1054                 goto out_unlock;
1055         }
1056
1057         /* We manipulate the conntrack inside the global conntrack table lock,
1058          * so there's no need to increase the refcount */
1059         err = -EEXIST;
1060         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1061                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1062
1063 out_unlock:
1064         write_unlock_bh(&nf_conntrack_lock);
1065         return err;
1066 }
1067
1068 /***********************************************************************
1069  * EXPECT
1070  ***********************************************************************/
1071
1072 static inline int
1073 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1074                          const struct nf_conntrack_tuple *tuple,
1075                          enum ctattr_expect type)
1076 {
1077         struct nfattr *nest_parms = NFA_NEST(skb, type);
1078
1079         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1080                 goto nfattr_failure;
1081
1082         NFA_NEST_END(skb, nest_parms);
1083
1084         return 0;
1085
1086 nfattr_failure:
1087         return -1;
1088 }
1089
1090 static inline int
1091 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1092                         const struct nf_conntrack_tuple *tuple,
1093                         const struct nf_conntrack_tuple *mask)
1094 {
1095         int ret;
1096         struct nf_conntrack_l3proto *l3proto;
1097         struct nf_conntrack_l4proto *l4proto;
1098         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1099
1100         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1101         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1102         nf_ct_l3proto_put(l3proto);
1103
1104         if (unlikely(ret < 0))
1105                 goto nfattr_failure;
1106
1107         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1108         ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);
1109         nf_ct_l4proto_put(l4proto);
1110         if (unlikely(ret < 0))
1111                 goto nfattr_failure;
1112
1113         NFA_NEST_END(skb, nest_parms);
1114
1115         return 0;
1116
1117 nfattr_failure:
1118         return -1;
1119 }
1120
1121 static inline int
1122 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1123                           const struct nf_conntrack_expect *exp)
1124 {
1125         struct nf_conn *master = exp->master;
1126         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1127         __be32 id = htonl(exp->id);
1128
1129         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1130                 goto nfattr_failure;
1131         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1132                 goto nfattr_failure;
1133         if (ctnetlink_exp_dump_tuple(skb,
1134                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1135                                  CTA_EXPECT_MASTER) < 0)
1136                 goto nfattr_failure;
1137
1138         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1139         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1140
1141         return 0;
1142
1143 nfattr_failure:
1144         return -1;
1145 }
1146
1147 static int
1148 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1149                     int event,
1150                     int nowait,
1151                     const struct nf_conntrack_expect *exp)
1152 {
1153         struct nlmsghdr *nlh;
1154         struct nfgenmsg *nfmsg;
1155         unsigned char *b;
1156
1157         b = skb->tail;
1158
1159         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1160         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1161         nfmsg  = NLMSG_DATA(nlh);
1162
1163         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1164         nfmsg->nfgen_family = exp->tuple.src.l3num;
1165         nfmsg->version      = NFNETLINK_V0;
1166         nfmsg->res_id       = 0;
1167
1168         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1169                 goto nfattr_failure;
1170
1171         nlh->nlmsg_len = skb->tail - b;
1172         return skb->len;
1173
1174 nlmsg_failure:
1175 nfattr_failure:
1176         skb_trim(skb, b - skb->data);
1177         return -1;
1178 }
1179
1180 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1181 static int ctnetlink_expect_event(struct notifier_block *this,
1182                                   unsigned long events, void *ptr)
1183 {
1184         struct nlmsghdr *nlh;
1185         struct nfgenmsg *nfmsg;
1186         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1187         struct sk_buff *skb;
1188         unsigned int type;
1189         unsigned char *b;
1190         int flags = 0;
1191
1192         if (events & IPEXP_NEW) {
1193                 type = IPCTNL_MSG_EXP_NEW;
1194                 flags = NLM_F_CREATE|NLM_F_EXCL;
1195         } else
1196                 return NOTIFY_DONE;
1197
1198         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1199                 return NOTIFY_DONE;
1200
1201         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1202         if (!skb)
1203                 return NOTIFY_DONE;
1204
1205         b = skb->tail;
1206
1207         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1208         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1209         nfmsg = NLMSG_DATA(nlh);
1210
1211         nlh->nlmsg_flags    = flags;
1212         nfmsg->nfgen_family = exp->tuple.src.l3num;
1213         nfmsg->version      = NFNETLINK_V0;
1214         nfmsg->res_id       = 0;
1215
1216         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1217                 goto nfattr_failure;
1218
1219         nlh->nlmsg_len = skb->tail - b;
1220         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1221         return NOTIFY_DONE;
1222
1223 nlmsg_failure:
1224 nfattr_failure:
1225         kfree_skb(skb);
1226         return NOTIFY_DONE;
1227 }
1228 #endif
1229
1230 static int
1231 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1232 {
1233         struct nf_conntrack_expect *exp = NULL;
1234         struct list_head *i;
1235         u_int32_t *id = (u_int32_t *) &cb->args[0];
1236         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1237         u_int8_t l3proto = nfmsg->nfgen_family;
1238
1239         read_lock_bh(&nf_conntrack_lock);
1240         list_for_each_prev(i, &nf_conntrack_expect_list) {
1241                 exp = (struct nf_conntrack_expect *) i;
1242                 if (l3proto && exp->tuple.src.l3num != l3proto)
1243                         continue;
1244                 if (exp->id <= *id)
1245                         continue;
1246                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1247                                             cb->nlh->nlmsg_seq,
1248                                             IPCTNL_MSG_EXP_NEW,
1249                                             1, exp) < 0)
1250                         goto out;
1251                 *id = exp->id;
1252         }
1253 out:
1254         read_unlock_bh(&nf_conntrack_lock);
1255
1256         return skb->len;
1257 }
1258
1259 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1260         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1261         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1262 };
1263
1264 static int
1265 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1266                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1267 {
1268         struct nf_conntrack_tuple tuple;
1269         struct nf_conntrack_expect *exp;
1270         struct sk_buff *skb2;
1271         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1272         u_int8_t u3 = nfmsg->nfgen_family;
1273         int err = 0;
1274
1275         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1276                 return -EINVAL;
1277
1278         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1279                 u32 rlen;
1280
1281                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1282                                                 ctnetlink_exp_dump_table,
1283                                                 ctnetlink_done)) != 0)
1284                         return -EINVAL;
1285                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1286                 if (rlen > skb->len)
1287                         rlen = skb->len;
1288                 skb_pull(skb, rlen);
1289                 return 0;
1290         }
1291
1292         if (cda[CTA_EXPECT_MASTER-1])
1293                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1294         else
1295                 return -EINVAL;
1296
1297         if (err < 0)
1298                 return err;
1299
1300         exp = nf_conntrack_expect_find_get(&tuple);
1301         if (!exp)
1302                 return -ENOENT;
1303
1304         if (cda[CTA_EXPECT_ID-1]) {
1305                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1306                 if (exp->id != ntohl(id)) {
1307                         nf_conntrack_expect_put(exp);
1308                         return -ENOENT;
1309                 }
1310         }
1311
1312         err = -ENOMEM;
1313         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1314         if (!skb2)
1315                 goto out;
1316
1317         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1318                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1319                                       1, exp);
1320         if (err <= 0)
1321                 goto free;
1322
1323         nf_conntrack_expect_put(exp);
1324
1325         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1326
1327 free:
1328         kfree_skb(skb2);
1329 out:
1330         nf_conntrack_expect_put(exp);
1331         return err;
1332 }
1333
1334 static int
1335 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1336                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1337 {
1338         struct nf_conntrack_expect *exp, *tmp;
1339         struct nf_conntrack_tuple tuple;
1340         struct nf_conntrack_helper *h;
1341         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1342         u_int8_t u3 = nfmsg->nfgen_family;
1343         int err;
1344
1345         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1346                 return -EINVAL;
1347
1348         if (cda[CTA_EXPECT_TUPLE-1]) {
1349                 /* delete a single expect by tuple */
1350                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1351                 if (err < 0)
1352                         return err;
1353
1354                 /* bump usage count to 2 */
1355                 exp = nf_conntrack_expect_find_get(&tuple);
1356                 if (!exp)
1357                         return -ENOENT;
1358
1359                 if (cda[CTA_EXPECT_ID-1]) {
1360                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1361                         if (exp->id != ntohl(id)) {
1362                                 nf_conntrack_expect_put(exp);
1363                                 return -ENOENT;
1364                         }
1365                 }
1366
1367                 /* after list removal, usage count == 1 */
1368                 nf_conntrack_unexpect_related(exp);
1369                 /* have to put what we 'get' above.
1370                  * after this line usage count == 0 */
1371                 nf_conntrack_expect_put(exp);
1372         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1373                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1374
1375                 /* delete all expectations for this helper */
1376                 write_lock_bh(&nf_conntrack_lock);
1377                 h = __nf_conntrack_helper_find_byname(name);
1378                 if (!h) {
1379                         write_unlock_bh(&nf_conntrack_lock);
1380                         return -EINVAL;
1381                 }
1382                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1383                                          list) {
1384                         struct nf_conn_help *m_help = nfct_help(exp->master);
1385                         if (m_help->helper == h
1386                             && 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         } else {
1393                 /* This basically means we have to flush everything*/
1394                 write_lock_bh(&nf_conntrack_lock);
1395                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1396                                          list) {
1397                         if (del_timer(&exp->timeout)) {
1398                                 nf_ct_unlink_expect(exp);
1399                                 nf_conntrack_expect_put(exp);
1400                         }
1401                 }
1402                 write_unlock_bh(&nf_conntrack_lock);
1403         }
1404
1405         return 0;
1406 }
1407 static int
1408 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1409 {
1410         return -EOPNOTSUPP;
1411 }
1412
1413 static int
1414 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1415 {
1416         struct nf_conntrack_tuple tuple, mask, master_tuple;
1417         struct nf_conntrack_tuple_hash *h = NULL;
1418         struct nf_conntrack_expect *exp;
1419         struct nf_conn *ct;
1420         struct nf_conn_help *help;
1421         int err = 0;
1422
1423         /* caller guarantees that those three CTA_EXPECT_* exist */
1424         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1425         if (err < 0)
1426                 return err;
1427         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1428         if (err < 0)
1429                 return err;
1430         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1431         if (err < 0)
1432                 return err;
1433
1434         /* Look for master conntrack of this expectation */
1435         h = nf_conntrack_find_get(&master_tuple, NULL);
1436         if (!h)
1437                 return -ENOENT;
1438         ct = nf_ct_tuplehash_to_ctrack(h);
1439         help = nfct_help(ct);
1440
1441         if (!help || !help->helper) {
1442                 /* such conntrack hasn't got any helper, abort */
1443                 err = -EINVAL;
1444                 goto out;
1445         }
1446
1447         exp = nf_conntrack_expect_alloc(ct);
1448         if (!exp) {
1449                 err = -ENOMEM;
1450                 goto out;
1451         }
1452
1453         exp->expectfn = NULL;
1454         exp->flags = 0;
1455         exp->master = ct;
1456         exp->helper = NULL;
1457         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1458         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1459
1460         err = nf_conntrack_expect_related(exp);
1461         nf_conntrack_expect_put(exp);
1462
1463 out:
1464         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1465         return err;
1466 }
1467
1468 static int
1469 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1470                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1471 {
1472         struct nf_conntrack_tuple tuple;
1473         struct nf_conntrack_expect *exp;
1474         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1475         u_int8_t u3 = nfmsg->nfgen_family;
1476         int err = 0;
1477
1478         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1479                 return -EINVAL;
1480
1481         if (!cda[CTA_EXPECT_TUPLE-1]
1482             || !cda[CTA_EXPECT_MASK-1]
1483             || !cda[CTA_EXPECT_MASTER-1])
1484                 return -EINVAL;
1485
1486         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1487         if (err < 0)
1488                 return err;
1489
1490         write_lock_bh(&nf_conntrack_lock);
1491         exp = __nf_conntrack_expect_find(&tuple);
1492
1493         if (!exp) {
1494                 write_unlock_bh(&nf_conntrack_lock);
1495                 err = -ENOENT;
1496                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1497                         err = ctnetlink_create_expect(cda, u3);
1498                 return err;
1499         }
1500
1501         err = -EEXIST;
1502         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1503                 err = ctnetlink_change_expect(exp, cda);
1504         write_unlock_bh(&nf_conntrack_lock);
1505
1506         return err;
1507 }
1508
1509 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1510 static struct notifier_block ctnl_notifier = {
1511         .notifier_call  = ctnetlink_conntrack_event,
1512 };
1513
1514 static struct notifier_block ctnl_notifier_exp = {
1515         .notifier_call  = ctnetlink_expect_event,
1516 };
1517 #endif
1518
1519 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1520         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1521                                             .attr_count = CTA_MAX, },
1522         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1523                                             .attr_count = CTA_MAX, },
1524         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1525                                             .attr_count = CTA_MAX, },
1526         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1527                                             .attr_count = CTA_MAX, },
1528 };
1529
1530 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1531         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1532                                             .attr_count = CTA_EXPECT_MAX, },
1533         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1534                                             .attr_count = CTA_EXPECT_MAX, },
1535         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1536                                             .attr_count = CTA_EXPECT_MAX, },
1537 };
1538
1539 static struct nfnetlink_subsystem ctnl_subsys = {
1540         .name                           = "conntrack",
1541         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1542         .cb_count                       = IPCTNL_MSG_MAX,
1543         .cb                             = ctnl_cb,
1544 };
1545
1546 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1547         .name                           = "conntrack_expect",
1548         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1549         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1550         .cb                             = ctnl_exp_cb,
1551 };
1552
1553 MODULE_ALIAS("ip_conntrack_netlink");
1554 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1555 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1556
1557 static int __init ctnetlink_init(void)
1558 {
1559         int ret;
1560
1561         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1562         ret = nfnetlink_subsys_register(&ctnl_subsys);
1563         if (ret < 0) {
1564                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1565                 goto err_out;
1566         }
1567
1568         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1569         if (ret < 0) {
1570                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1571                 goto err_unreg_subsys;
1572         }
1573
1574 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1575         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1576         if (ret < 0) {
1577                 printk("ctnetlink_init: cannot register notifier.\n");
1578                 goto err_unreg_exp_subsys;
1579         }
1580
1581         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1582         if (ret < 0) {
1583                 printk("ctnetlink_init: cannot expect register notifier.\n");
1584                 goto err_unreg_notifier;
1585         }
1586 #endif
1587
1588         return 0;
1589
1590 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1591 err_unreg_notifier:
1592         nf_conntrack_unregister_notifier(&ctnl_notifier);
1593 err_unreg_exp_subsys:
1594         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1595 #endif
1596 err_unreg_subsys:
1597         nfnetlink_subsys_unregister(&ctnl_subsys);
1598 err_out:
1599         return ret;
1600 }
1601
1602 static void __exit ctnetlink_exit(void)
1603 {
1604         printk("ctnetlink: unregistering from nfnetlink.\n");
1605
1606 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1607         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1608         nf_conntrack_unregister_notifier(&ctnl_notifier);
1609 #endif
1610
1611         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1612         nfnetlink_subsys_unregister(&ctnl_subsys);
1613         return;
1614 }
1615
1616 module_init(ctnetlink_init);
1617 module_exit(ctnetlink_exit);