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                 if ((events & IPCT_MARK || ct->mark)
 393                     && ctnetlink_dump_mark(skb, ct) < 0)
 394                         goto nfattr_failure;
 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;
1154
1155         b = skb->tail;
1156
1157         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1158         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1159         nfmsg  = NLMSG_DATA(nlh);
1160
1161         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1162         nfmsg->nfgen_family = exp->tuple.src.l3num;
1163         nfmsg->version      = NFNETLINK_V0;
1164         nfmsg->res_id       = 0;
1165
1166         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1167                 goto nfattr_failure;
1168
1169         nlh->nlmsg_len = skb->tail - b;
1170         return skb->len;
1171
1172 nlmsg_failure:
1173 nfattr_failure:
1174         skb_trim(skb, b - skb->data);
1175         return -1;
1176 }
1177
1178 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1179 static int ctnetlink_expect_event(struct notifier_block *this,
1180                                   unsigned long events, void *ptr)
1181 {
1182         struct nlmsghdr *nlh;
1183         struct nfgenmsg *nfmsg;
1184         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1185         struct sk_buff *skb;
1186         unsigned int type;
1187         unsigned char *b;
1188         int flags = 0;
1189
1190         if (events & IPEXP_NEW) {
1191                 type = IPCTNL_MSG_EXP_NEW;
1192                 flags = NLM_F_CREATE|NLM_F_EXCL;
1193         } else
1194                 return NOTIFY_DONE;
1195
1196         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1197                 return NOTIFY_DONE;
1198
1199         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1200         if (!skb)
1201                 return NOTIFY_DONE;
1202
1203         b = skb->tail;
1204
1205         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1206         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1207         nfmsg = NLMSG_DATA(nlh);
1208
1209         nlh->nlmsg_flags    = flags;
1210         nfmsg->nfgen_family = exp->tuple.src.l3num;
1211         nfmsg->version      = NFNETLINK_V0;
1212         nfmsg->res_id       = 0;
1213
1214         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1215                 goto nfattr_failure;
1216
1217         nlh->nlmsg_len = skb->tail - b;
1218         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1219         return NOTIFY_DONE;
1220
1221 nlmsg_failure:
1222 nfattr_failure:
1223         kfree_skb(skb);
1224         return NOTIFY_DONE;
1225 }
1226 #endif
1227
1228 static int
1229 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1230 {
1231         struct nf_conntrack_expect *exp = NULL;
1232         struct list_head *i;
1233         u_int32_t *id = (u_int32_t *) &cb->args[0];
1234         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1235         u_int8_t l3proto = nfmsg->nfgen_family;
1236
1237         read_lock_bh(&nf_conntrack_lock);
1238         list_for_each_prev(i, &nf_conntrack_expect_list) {
1239                 exp = (struct nf_conntrack_expect *) i;
1240                 if (l3proto && exp->tuple.src.l3num != l3proto)
1241                         continue;
1242                 if (exp->id <= *id)
1243                         continue;
1244                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1245                                             cb->nlh->nlmsg_seq,
1246                                             IPCTNL_MSG_EXP_NEW,
1247                                             1, exp) < 0)
1248                         goto out;
1249                 *id = exp->id;
1250         }
1251 out:
1252         read_unlock_bh(&nf_conntrack_lock);
1253
1254         return skb->len;
1255 }
1256
1257 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1258         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1259         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1260 };
1261
1262 static int
1263 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1264                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1265 {
1266         struct nf_conntrack_tuple tuple;
1267         struct nf_conntrack_expect *exp;
1268         struct sk_buff *skb2;
1269         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1270         u_int8_t u3 = nfmsg->nfgen_family;
1271         int err = 0;
1272
1273         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1274                 return -EINVAL;
1275
1276         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1277                 u32 rlen;
1278
1279                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1280                                                 ctnetlink_exp_dump_table,
1281                                                 ctnetlink_done)) != 0)
1282                         return -EINVAL;
1283                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1284                 if (rlen > skb->len)
1285                         rlen = skb->len;
1286                 skb_pull(skb, rlen);
1287                 return 0;
1288         }
1289
1290         if (cda[CTA_EXPECT_MASTER-1])
1291                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1292         else
1293                 return -EINVAL;
1294
1295         if (err < 0)
1296                 return err;
1297
1298         exp = nf_conntrack_expect_find_get(&tuple);
1299         if (!exp)
1300                 return -ENOENT;
1301
1302         if (cda[CTA_EXPECT_ID-1]) {
1303                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1304                 if (exp->id != ntohl(id)) {
1305                         nf_conntrack_expect_put(exp);
1306                         return -ENOENT;
1307                 }
1308         }
1309
1310         err = -ENOMEM;
1311         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1312         if (!skb2)
1313                 goto out;
1314
1315         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1316                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1317                                       1, exp);
1318         if (err <= 0)
1319                 goto free;
1320
1321         nf_conntrack_expect_put(exp);
1322
1323         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1324
1325 free:
1326         kfree_skb(skb2);
1327 out:
1328         nf_conntrack_expect_put(exp);
1329         return err;
1330 }
1331
1332 static int
1333 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1334                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1335 {
1336         struct nf_conntrack_expect *exp, *tmp;
1337         struct nf_conntrack_tuple tuple;
1338         struct nf_conntrack_helper *h;
1339         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1340         u_int8_t u3 = nfmsg->nfgen_family;
1341         int err;
1342
1343         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1344                 return -EINVAL;
1345
1346         if (cda[CTA_EXPECT_TUPLE-1]) {
1347                 /* delete a single expect by tuple */
1348                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1349                 if (err < 0)
1350                         return err;
1351
1352                 /* bump usage count to 2 */
1353                 exp = nf_conntrack_expect_find_get(&tuple);
1354                 if (!exp)
1355                         return -ENOENT;
1356
1357                 if (cda[CTA_EXPECT_ID-1]) {
1358                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1359                         if (exp->id != ntohl(id)) {
1360                                 nf_conntrack_expect_put(exp);
1361                                 return -ENOENT;
1362                         }
1363                 }
1364
1365                 /* after list removal, usage count == 1 */
1366                 nf_conntrack_unexpect_related(exp);
1367                 /* have to put what we 'get' above.
1368                  * after this line usage count == 0 */
1369                 nf_conntrack_expect_put(exp);
1370         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1371                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1372
1373                 /* delete all expectations for this helper */
1374                 write_lock_bh(&nf_conntrack_lock);
1375                 h = __nf_conntrack_helper_find_byname(name);
1376                 if (!h) {
1377                         write_unlock_bh(&nf_conntrack_lock);
1378                         return -EINVAL;
1379                 }
1380                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1381                                          list) {
1382                         struct nf_conn_help *m_help = nfct_help(exp->master);
1383                         if (m_help->helper == h
1384                             && del_timer(&exp->timeout)) {
1385                                 nf_ct_unlink_expect(exp);
1386                                 nf_conntrack_expect_put(exp);
1387                         }
1388                 }
1389                 write_unlock_bh(&nf_conntrack_lock);
1390         } else {
1391                 /* This basically means we have to flush everything*/
1392                 write_lock_bh(&nf_conntrack_lock);
1393                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1394                                          list) {
1395                         if (del_timer(&exp->timeout)) {
1396                                 nf_ct_unlink_expect(exp);
1397                                 nf_conntrack_expect_put(exp);
1398                         }
1399                 }
1400                 write_unlock_bh(&nf_conntrack_lock);
1401         }
1402
1403         return 0;
1404 }
1405 static int
1406 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1407 {
1408         return -EOPNOTSUPP;
1409 }
1410
1411 static int
1412 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1413 {
1414         struct nf_conntrack_tuple tuple, mask, master_tuple;
1415         struct nf_conntrack_tuple_hash *h = NULL;
1416         struct nf_conntrack_expect *exp;
1417         struct nf_conn *ct;
1418         struct nf_conn_help *help;
1419         int err = 0;
1420
1421         /* caller guarantees that those three CTA_EXPECT_* exist */
1422         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1423         if (err < 0)
1424                 return err;
1425         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1426         if (err < 0)
1427                 return err;
1428         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1429         if (err < 0)
1430                 return err;
1431
1432         /* Look for master conntrack of this expectation */
1433         h = nf_conntrack_find_get(&master_tuple, NULL);
1434         if (!h)
1435                 return -ENOENT;
1436         ct = nf_ct_tuplehash_to_ctrack(h);
1437         help = nfct_help(ct);
1438
1439         if (!help || !help->helper) {
1440                 /* such conntrack hasn't got any helper, abort */
1441                 err = -EINVAL;
1442                 goto out;
1443         }
1444
1445         exp = nf_conntrack_expect_alloc(ct);
1446         if (!exp) {
1447                 err = -ENOMEM;
1448                 goto out;
1449         }
1450
1451         exp->expectfn = NULL;
1452         exp->flags = 0;
1453         exp->master = ct;
1454         exp->helper = NULL;
1455         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1456         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1457
1458         err = nf_conntrack_expect_related(exp);
1459         nf_conntrack_expect_put(exp);
1460
1461 out:
1462         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1463         return err;
1464 }
1465
1466 static int
1467 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1468                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1469 {
1470         struct nf_conntrack_tuple tuple;
1471         struct nf_conntrack_expect *exp;
1472         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1473         u_int8_t u3 = nfmsg->nfgen_family;
1474         int err = 0;
1475
1476         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1477                 return -EINVAL;
1478
1479         if (!cda[CTA_EXPECT_TUPLE-1]
1480             || !cda[CTA_EXPECT_MASK-1]
1481             || !cda[CTA_EXPECT_MASTER-1])
1482                 return -EINVAL;
1483
1484         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1485         if (err < 0)
1486                 return err;
1487
1488         write_lock_bh(&nf_conntrack_lock);
1489         exp = __nf_conntrack_expect_find(&tuple);
1490
1491         if (!exp) {
1492                 write_unlock_bh(&nf_conntrack_lock);
1493                 err = -ENOENT;
1494                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1495                         err = ctnetlink_create_expect(cda, u3);
1496                 return err;
1497         }
1498
1499         err = -EEXIST;
1500         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1501                 err = ctnetlink_change_expect(exp, cda);
1502         write_unlock_bh(&nf_conntrack_lock);
1503
1504         return err;
1505 }
1506
1507 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1508 static struct notifier_block ctnl_notifier = {
1509         .notifier_call  = ctnetlink_conntrack_event,
1510 };
1511
1512 static struct notifier_block ctnl_notifier_exp = {
1513         .notifier_call  = ctnetlink_expect_event,
1514 };
1515 #endif
1516
1517 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1518         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1519                                             .attr_count = CTA_MAX, },
1520         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1521                                             .attr_count = CTA_MAX, },
1522         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1523                                             .attr_count = CTA_MAX, },
1524         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1525                                             .attr_count = CTA_MAX, },
1526 };
1527
1528 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1529         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1530                                             .attr_count = CTA_EXPECT_MAX, },
1531         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1532                                             .attr_count = CTA_EXPECT_MAX, },
1533         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1534                                             .attr_count = CTA_EXPECT_MAX, },
1535 };
1536
1537 static struct nfnetlink_subsystem ctnl_subsys = {
1538         .name                           = "conntrack",
1539         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1540         .cb_count                       = IPCTNL_MSG_MAX,
1541         .cb                             = ctnl_cb,
1542 };
1543
1544 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1545         .name                           = "conntrack_expect",
1546         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1547         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1548         .cb                             = ctnl_exp_cb,
1549 };
1550
1551 MODULE_ALIAS("ip_conntrack_netlink");
1552 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1553 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1554
1555 static int __init ctnetlink_init(void)
1556 {
1557         int ret;
1558
1559         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1560         ret = nfnetlink_subsys_register(&ctnl_subsys);
1561         if (ret < 0) {
1562                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1563                 goto err_out;
1564         }
1565
1566         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1567         if (ret < 0) {
1568                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1569                 goto err_unreg_subsys;
1570         }
1571
1572 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1573         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1574         if (ret < 0) {
1575                 printk("ctnetlink_init: cannot register notifier.\n");
1576                 goto err_unreg_exp_subsys;
1577         }
1578
1579         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1580         if (ret < 0) {
1581                 printk("ctnetlink_init: cannot expect register notifier.\n");
1582                 goto err_unreg_notifier;
1583         }
1584 #endif
1585
1586         return 0;
1587
1588 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1589 err_unreg_notifier:
1590         nf_conntrack_unregister_notifier(&ctnl_notifier);
1591 err_unreg_exp_subsys:
1592         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1593 #endif
1594 err_unreg_subsys:
1595         nfnetlink_subsys_unregister(&ctnl_subsys);
1596 err_out:
1597         return ret;
1598 }
1599
1600 static void __exit ctnetlink_exit(void)
1601 {
1602         printk("ctnetlink: unregistering from nfnetlink.\n");
1603
1604 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1605         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1606         nf_conntrack_unregister_notifier(&ctnl_notifier);
1607 #endif
1608
1609         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1610         nfnetlink_subsys_unregister(&ctnl_subsys);
1611         return;
1612 }
1613
1614 module_init(ctnetlink_init);
1615 module_exit(ctnetlink_exit);