net/netfilter/nf_conntrack_netlink.c

   1 /* Connection tracking via netlink socket. Allows for user space
   2  * protocol helpers and general trouble making from userspace.
   3  *
   4  * (C) 2001 by Jay Schulist <jschlst@samba.org>
   5  * (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
   6  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
   7  * (C) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net>
   8  *
   9  * Initial connection tracking via netlink development funded and
  10  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
  11  *
  12  * Further development of this code funded by Astaro AG (http://www.astaro.com)
  13  *
  14  * This software may be used and distributed according to the terms
  15  * of the GNU General Public License, incorporated herein by reference.
  16  */
  17
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/types.h>
  22 #include <linux/timer.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/errno.h>
  25 #include <linux/netlink.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/notifier.h>
  29
  30 #include <linux/netfilter.h>
  31 #include <net/netlink.h>
  32 #include <net/netfilter/nf_conntrack.h>
  33 #include <net/netfilter/nf_conntrack_core.h>
  34 #include <net/netfilter/nf_conntrack_expect.h>
  35 #include <net/netfilter/nf_conntrack_helper.h>
  36 #include <net/netfilter/nf_conntrack_l3proto.h>
  37 #include <net/netfilter/nf_conntrack_l4proto.h>
  38 #include <net/netfilter/nf_conntrack_tuple.h>
  39 #ifdef CONFIG_NF_NAT_NEEDED
  40 #include <net/netfilter/nf_nat_core.h>
  41 #include <net/netfilter/nf_nat_protocol.h>
  42 #endif
  43
  44 #include <linux/netfilter/nfnetlink.h>
  45 #include <linux/netfilter/nfnetlink_conntrack.h>
  46
  47 MODULE_LICENSE("GPL");
  48
  49 static char __initdata version[] = "0.93";
  50
  51 static inline int
  52 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  53                             const struct nf_conntrack_tuple *tuple,
  54                             struct nf_conntrack_l4proto *l4proto)
  55 {
  56         int ret = 0;
  57         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  58
  59         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  60
  61         if (likely(l4proto->tuple_to_nfattr))
  62                 ret = l4proto->tuple_to_nfattr(skb, tuple);
  63
  64         NFA_NEST_END(skb, nest_parms);
  65
  66         return ret;
  67
  68 nfattr_failure:
  69         return -1;
  70 }
  71
  72 static inline int
  73 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  74                          const struct nf_conntrack_tuple *tuple,
  75                          struct nf_conntrack_l3proto *l3proto)
  76 {
  77         int ret = 0;
  78         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  79
  80         if (likely(l3proto->tuple_to_nfattr))
  81                 ret = l3proto->tuple_to_nfattr(skb, tuple);
  82
  83         NFA_NEST_END(skb, nest_parms);
  84
  85         return ret;
  86
  87 nfattr_failure:
  88         return -1;
  89 }
  90
  91 static inline int
  92 ctnetlink_dump_tuples(struct sk_buff *skb,
  93                       const struct nf_conntrack_tuple *tuple)
  94 {
  95         int ret;
  96         struct nf_conntrack_l3proto *l3proto;
  97         struct nf_conntrack_l4proto *l4proto;
  98
  99         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 100         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 101         nf_ct_l3proto_put(l3proto);
 102
 103         if (unlikely(ret < 0))
 104                 return ret;
 105
 106         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 107         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
 108         nf_ct_l4proto_put(l4proto);
 109
 110         return ret;
 111 }
 112
 113 static inline int
 114 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 115 {
 116         __be32 status = htonl((u_int32_t) ct->status);
 117         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 118         return 0;
 119
 120 nfattr_failure:
 121         return -1;
 122 }
 123
 124 static inline int
 125 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 126 {
 127         long timeout_l = ct->timeout.expires - jiffies;
 128         __be32 timeout;
 129
 130         if (timeout_l < 0)
 131                 timeout = 0;
 132         else
 133                 timeout = htonl(timeout_l / HZ);
 134
 135         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 136         return 0;
 137
 138 nfattr_failure:
 139         return -1;
 140 }
 141
 142 static inline int
 143 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 144 {
 145         struct nf_conntrack_l4proto *l4proto = nf_ct_l4proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 146         struct nfattr *nest_proto;
 147         int ret;
 148
 149         if (!l4proto->to_nfattr) {
 150                 nf_ct_l4proto_put(l4proto);
 151                 return 0;
 152         }
 153
 154         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 155
 156         ret = l4proto->to_nfattr(skb, nest_proto, ct);
 157
 158         nf_ct_l4proto_put(l4proto);
 159
 160         NFA_NEST_END(skb, nest_proto);
 161
 162         return ret;
 163
 164 nfattr_failure:
 165         nf_ct_l4proto_put(l4proto);
 166         return -1;
 167 }
 168
 169 static inline int
 170 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 171 {
 172         struct nfattr *nest_helper;
 173         const struct nf_conn_help *help = nfct_help(ct);
 174
 175         if (!help || !help->helper)
 176                 return 0;
 177
 178         nest_helper = NFA_NEST(skb, CTA_HELP);
 179         NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
 180
 181         if (help->helper->to_nfattr)
 182                 help->helper->to_nfattr(skb, ct);
 183
 184         NFA_NEST_END(skb, nest_helper);
 185
 186         return 0;
 187
 188 nfattr_failure:
 189         return -1;
 190 }
 191
 192 #ifdef CONFIG_NF_CT_ACCT
 193 static inline int
 194 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 195                         enum ip_conntrack_dir dir)
 196 {
 197         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 198         struct nfattr *nest_count = NFA_NEST(skb, type);
 199         __be32 tmp;
 200
 201         tmp = htonl(ct->counters[dir].packets);
 202         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 203
 204         tmp = htonl(ct->counters[dir].bytes);
 205         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 206
 207         NFA_NEST_END(skb, nest_count);
 208
 209         return 0;
 210
 211 nfattr_failure:
 212         return -1;
 213 }
 214 #else
 215 #define ctnetlink_dump_counters(a, b, c) (0)
 216 #endif
 217
 218 #ifdef CONFIG_NF_CONNTRACK_MARK
 219 static inline int
 220 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 221 {
 222         __be32 mark = htonl(ct->mark);
 223
 224         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 225         return 0;
 226
 227 nfattr_failure:
 228         return -1;
 229 }
 230 #else
 231 #define ctnetlink_dump_mark(a, b) (0)
 232 #endif
 233
 234 static inline int
 235 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 236 {
 237         __be32 id = htonl(ct->id);
 238         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 239         return 0;
 240
 241 nfattr_failure:
 242         return -1;
 243 }
 244
 245 static inline int
 246 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 247 {
 248         __be32 use = htonl(atomic_read(&ct->ct_general.use));
 249
 250         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 251         return 0;
 252
 253 nfattr_failure:
 254         return -1;
 255 }
 256
 257 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 258
 259 static int
 260 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 261                     int event, int nowait,
 262                     const struct nf_conn *ct)
 263 {
 264         struct nlmsghdr *nlh;
 265         struct nfgenmsg *nfmsg;
 266         struct nfattr *nest_parms;
 267         unsigned char *b = skb_tail_pointer(skb);
 268
 269         event |= NFNL_SUBSYS_CTNETLINK << 8;
 270         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 271         nfmsg  = NLMSG_DATA(nlh);
 272
 273         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 274         nfmsg->nfgen_family =
 275                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 276         nfmsg->version      = NFNETLINK_V0;
 277         nfmsg->res_id       = 0;
 278
 279         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 280         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 281                 goto nfattr_failure;
 282         NFA_NEST_END(skb, nest_parms);
 283
 284         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 285         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 286                 goto nfattr_failure;
 287         NFA_NEST_END(skb, nest_parms);
 288
 289         if (ctnetlink_dump_status(skb, ct) < 0 ||
 290             ctnetlink_dump_timeout(skb, ct) < 0 ||
 291             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 292             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 293             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 294             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 295             ctnetlink_dump_mark(skb, ct) < 0 ||
 296             ctnetlink_dump_id(skb, ct) < 0 ||
 297             ctnetlink_dump_use(skb, ct) < 0)
 298                 goto nfattr_failure;
 299
 300         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 301         return skb->len;
 302
 303 nlmsg_failure:
 304 nfattr_failure:
 305         nlmsg_trim(skb, b);
 306         return -1;
 307 }
 308
 309 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 310 static int ctnetlink_conntrack_event(struct notifier_block *this,
 311                                      unsigned long events, void *ptr)
 312 {
 313         struct nlmsghdr *nlh;
 314         struct nfgenmsg *nfmsg;
 315         struct nfattr *nest_parms;
 316         struct nf_conn *ct = (struct nf_conn *)ptr;
 317         struct sk_buff *skb;
 318         unsigned int type;
 319         sk_buff_data_t b;
 320         unsigned int flags = 0, group;
 321
 322         /* ignore our fake conntrack entry */
 323         if (ct == &nf_conntrack_untracked)
 324                 return NOTIFY_DONE;
 325
 326         if (events & IPCT_DESTROY) {
 327                 type = IPCTNL_MSG_CT_DELETE;
 328                 group = NFNLGRP_CONNTRACK_DESTROY;
 329         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 330                 type = IPCTNL_MSG_CT_NEW;
 331                 flags = NLM_F_CREATE|NLM_F_EXCL;
 332                 group = NFNLGRP_CONNTRACK_NEW;
 333         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
 334                 type = IPCTNL_MSG_CT_NEW;
 335                 group = NFNLGRP_CONNTRACK_UPDATE;
 336         } else
 337                 return NOTIFY_DONE;
 338
 339         if (!nfnetlink_has_listeners(group))
 340                 return NOTIFY_DONE;
 341
 342         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 343         if (!skb)
 344                 return NOTIFY_DONE;
 345
 346         b = skb->tail;
 347
 348         type |= NFNL_SUBSYS_CTNETLINK << 8;
 349         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 350         nfmsg = NLMSG_DATA(nlh);
 351
 352         nlh->nlmsg_flags    = flags;
 353         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 354         nfmsg->version  = NFNETLINK_V0;
 355         nfmsg->res_id   = 0;
 356
 357         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 358         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 359                 goto nfattr_failure;
 360         NFA_NEST_END(skb, nest_parms);
 361
 362         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 363         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 364                 goto nfattr_failure;
 365         NFA_NEST_END(skb, nest_parms);
 366
 367         if (events & IPCT_DESTROY) {
 368                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 369                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 370                         goto nfattr_failure;
 371         } else {
 372                 if (ctnetlink_dump_status(skb, ct) < 0)
 373                         goto nfattr_failure;
 374
 375                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 376                         goto nfattr_failure;
 377
 378                 if (events & IPCT_PROTOINFO
 379                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 380                         goto nfattr_failure;
 381
 382                 if ((events & IPCT_HELPER || nfct_help(ct))
 383                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 384                         goto nfattr_failure;
 385
 386 #ifdef CONFIG_NF_CONNTRACK_MARK
 387                 if ((events & IPCT_MARK || ct->mark)
 388                     && ctnetlink_dump_mark(skb, ct) < 0)
 389                         goto nfattr_failure;
 390 #endif
 391
 392                 if (events & IPCT_COUNTER_FILLING &&
 393                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 394                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
 395                         goto nfattr_failure;
 396         }
 397
 398         nlh->nlmsg_len = skb->tail - b;
 399         nfnetlink_send(skb, 0, group, 0);
 400         return NOTIFY_DONE;
 401
 402 nlmsg_failure:
 403 nfattr_failure:
 404         kfree_skb(skb);
 405         return NOTIFY_DONE;
 406 }
 407 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 408
 409 static int ctnetlink_done(struct netlink_callback *cb)
 410 {
 411         if (cb->args[1])
 412                 nf_ct_put((struct nf_conn *)cb->args[1]);
 413         return 0;
 414 }
 415
 416 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 417
 418 static int
 419 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 420 {
 421         struct nf_conn *ct, *last;
 422         struct nf_conntrack_tuple_hash *h;
 423         struct list_head *i;
 424         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 425         u_int8_t l3proto = nfmsg->nfgen_family;
 426
 427         read_lock_bh(&nf_conntrack_lock);
 428         last = (struct nf_conn *)cb->args[1];
 429         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
 430 restart:
 431                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 432                         h = (struct nf_conntrack_tuple_hash *) i;
 433                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 434                                 continue;
 435                         ct = nf_ct_tuplehash_to_ctrack(h);
 436                         /* Dump entries of a given L3 protocol number.
 437                          * If it is not specified, ie. l3proto == 0,
 438                          * then dump everything. */
 439                         if (l3proto && L3PROTO(ct) != l3proto)
 440                                 continue;
 441                         if (cb->args[1]) {
 442                                 if (ct != last)
 443                                         continue;
 444                                 cb->args[1] = 0;
 445                         }
 446                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 447                                                 cb->nlh->nlmsg_seq,
 448                                                 IPCTNL_MSG_CT_NEW,
 449                                                 1, ct) < 0) {
 450                                 nf_conntrack_get(&ct->ct_general);
 451                                 cb->args[1] = (unsigned long)ct;
 452                                 goto out;
 453                         }
 454 #ifdef CONFIG_NF_CT_ACCT
 455                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
 456                                                 IPCTNL_MSG_CT_GET_CTRZERO)
 457                                 memset(&ct->counters, 0, sizeof(ct->counters));
 458 #endif
 459                 }
 460                 if (cb->args[1]) {
 461                         cb->args[1] = 0;
 462                         goto restart;
 463                 }
 464         }
 465 out:
 466         read_unlock_bh(&nf_conntrack_lock);
 467         if (last)
 468                 nf_ct_put(last);
 469
 470         return skb->len;
 471 }
 472
 473 static inline int
 474 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 475 {
 476         struct nfattr *tb[CTA_IP_MAX];
 477         struct nf_conntrack_l3proto *l3proto;
 478         int ret = 0;
 479
 480         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 481
 482         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 483
 484         if (likely(l3proto->nfattr_to_tuple))
 485                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 486
 487         nf_ct_l3proto_put(l3proto);
 488
 489         return ret;
 490 }
 491
 492 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 493         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 494 };
 495
 496 static inline int
 497 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 498                             struct nf_conntrack_tuple *tuple)
 499 {
 500         struct nfattr *tb[CTA_PROTO_MAX];
 501         struct nf_conntrack_l4proto *l4proto;
 502         int ret = 0;
 503
 504         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 505
 506         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 507                 return -EINVAL;
 508
 509         if (!tb[CTA_PROTO_NUM-1])
 510                 return -EINVAL;
 511         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 512
 513         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 514
 515         if (likely(l4proto->nfattr_to_tuple))
 516                 ret = l4proto->nfattr_to_tuple(tb, tuple);
 517
 518         nf_ct_l4proto_put(l4proto);
 519
 520         return ret;
 521 }
 522
 523 static inline int
 524 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 525                       enum ctattr_tuple type, u_int8_t l3num)
 526 {
 527         struct nfattr *tb[CTA_TUPLE_MAX];
 528         int err;
 529
 530         memset(tuple, 0, sizeof(*tuple));
 531
 532         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 533
 534         if (!tb[CTA_TUPLE_IP-1])
 535                 return -EINVAL;
 536
 537         tuple->src.l3num = l3num;
 538
 539         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 540         if (err < 0)
 541                 return err;
 542
 543         if (!tb[CTA_TUPLE_PROTO-1])
 544                 return -EINVAL;
 545
 546         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 547         if (err < 0)
 548                 return err;
 549
 550         /* orig and expect tuples get DIR_ORIGINAL */
 551         if (type == CTA_TUPLE_REPLY)
 552                 tuple->dst.dir = IP_CT_DIR_REPLY;
 553         else
 554                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 555
 556         return 0;
 557 }
 558
 559 #ifdef CONFIG_NF_NAT_NEEDED
 560 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 561         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 562         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 563 };
 564
 565 static int nfnetlink_parse_nat_proto(struct nfattr *attr,
 566                                      const struct nf_conn *ct,
 567                                      struct nf_nat_range *range)
 568 {
 569         struct nfattr *tb[CTA_PROTONAT_MAX];
 570         struct nf_nat_protocol *npt;
 571
 572         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 573
 574         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 575                 return -EINVAL;
 576
 577         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 578
 579         if (!npt->nfattr_to_range) {
 580                 nf_nat_proto_put(npt);
 581                 return 0;
 582         }
 583
 584         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 585         if (npt->nfattr_to_range(tb, range) > 0)
 586                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 587
 588         nf_nat_proto_put(npt);
 589
 590         return 0;
 591 }
 592
 593 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 594         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 595         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 596 };
 597
 598 static inline int
 599 nfnetlink_parse_nat(struct nfattr *nat,
 600                     const struct nf_conn *ct, struct nf_nat_range *range)
 601 {
 602         struct nfattr *tb[CTA_NAT_MAX];
 603         int err;
 604
 605         memset(range, 0, sizeof(*range));
 606
 607         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 608
 609         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 610                 return -EINVAL;
 611
 612         if (tb[CTA_NAT_MINIP-1])
 613                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 614
 615         if (!tb[CTA_NAT_MAXIP-1])
 616                 range->max_ip = range->min_ip;
 617         else
 618                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 619
 620         if (range->min_ip)
 621                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 622
 623         if (!tb[CTA_NAT_PROTO-1])
 624                 return 0;
 625
 626         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 627         if (err < 0)
 628                 return err;
 629
 630         return 0;
 631 }
 632 #endif
 633
 634 static inline int
 635 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 636 {
 637         struct nfattr *tb[CTA_HELP_MAX];
 638
 639         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 640
 641         if (!tb[CTA_HELP_NAME-1])
 642                 return -EINVAL;
 643
 644         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 645
 646         return 0;
 647 }
 648
 649 static const size_t cta_min[CTA_MAX] = {
 650         [CTA_STATUS-1]          = sizeof(u_int32_t),
 651         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 652         [CTA_MARK-1]            = sizeof(u_int32_t),
 653         [CTA_USE-1]             = sizeof(u_int32_t),
 654         [CTA_ID-1]              = sizeof(u_int32_t)
 655 };
 656
 657 static int
 658 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 659                         struct nlmsghdr *nlh, struct nfattr *cda[])
 660 {
 661         struct nf_conntrack_tuple_hash *h;
 662         struct nf_conntrack_tuple tuple;
 663         struct nf_conn *ct;
 664         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 665         u_int8_t u3 = nfmsg->nfgen_family;
 666         int err = 0;
 667
 668         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 669                 return -EINVAL;
 670
 671         if (cda[CTA_TUPLE_ORIG-1])
 672                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 673         else if (cda[CTA_TUPLE_REPLY-1])
 674                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 675         else {
 676                 /* Flush the whole table */
 677                 nf_conntrack_flush();
 678                 return 0;
 679         }
 680
 681         if (err < 0)
 682                 return err;
 683
 684         h = nf_conntrack_find_get(&tuple, NULL);
 685         if (!h)
 686                 return -ENOENT;
 687
 688         ct = nf_ct_tuplehash_to_ctrack(h);
 689
 690         if (cda[CTA_ID-1]) {
 691                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
 692                 if (ct->id != id) {
 693                         nf_ct_put(ct);
 694                         return -ENOENT;
 695                 }
 696         }
 697         if (del_timer(&ct->timeout))
 698                 ct->timeout.function((unsigned long)ct);
 699
 700         nf_ct_put(ct);
 701
 702         return 0;
 703 }
 704
 705 static int
 706 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 707                         struct nlmsghdr *nlh, struct nfattr *cda[])
 708 {
 709         struct nf_conntrack_tuple_hash *h;
 710         struct nf_conntrack_tuple tuple;
 711         struct nf_conn *ct;
 712         struct sk_buff *skb2 = NULL;
 713         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 714         u_int8_t u3 = nfmsg->nfgen_family;
 715         int err = 0;
 716
 717         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 718 #ifndef CONFIG_NF_CT_ACCT
 719                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
 720                         return -ENOTSUPP;
 721 #endif
 722                 return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
 723                                           ctnetlink_done);
 724         }
 725
 726         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 727                 return -EINVAL;
 728
 729         if (cda[CTA_TUPLE_ORIG-1])
 730                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 731         else if (cda[CTA_TUPLE_REPLY-1])
 732                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 733         else
 734                 return -EINVAL;
 735
 736         if (err < 0)
 737                 return err;
 738
 739         h = nf_conntrack_find_get(&tuple, NULL);
 740         if (!h)
 741                 return -ENOENT;
 742
 743         ct = nf_ct_tuplehash_to_ctrack(h);
 744
 745         err = -ENOMEM;
 746         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 747         if (!skb2) {
 748                 nf_ct_put(ct);
 749                 return -ENOMEM;
 750         }
 751
 752         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 753                                   IPCTNL_MSG_CT_NEW, 1, ct);
 754         nf_ct_put(ct);
 755         if (err <= 0)
 756                 goto free;
 757
 758         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 759         if (err < 0)
 760                 goto out;
 761
 762         return 0;
 763
 764 free:
 765         kfree_skb(skb2);
 766 out:
 767         return err;
 768 }
 769
 770 static inline int
 771 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 772 {
 773         unsigned long d;
 774         unsigned int status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));
 775         d = ct->status ^ status;
 776
 777         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 778                 /* unchangeable */
 779                 return -EINVAL;
 780
 781         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 782                 /* SEEN_REPLY bit can only be set */
 783                 return -EINVAL;
 784
 785
 786         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 787                 /* ASSURED bit can only be set */
 788                 return -EINVAL;
 789
 790         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 791 #ifndef CONFIG_NF_NAT_NEEDED
 792                 return -EINVAL;
 793 #else
 794                 struct nf_nat_range range;
 795
 796                 if (cda[CTA_NAT_DST-1]) {
 797                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 798                                                 &range) < 0)
 799                                 return -EINVAL;
 800                         if (nf_nat_initialized(ct,
 801                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 802                                 return -EEXIST;
 803                         nf_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
 804                 }
 805                 if (cda[CTA_NAT_SRC-1]) {
 806                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 807                                                 &range) < 0)
 808                                 return -EINVAL;
 809                         if (nf_nat_initialized(ct,
 810                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 811                                 return -EEXIST;
 812                         nf_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
 813                 }
 814 #endif
 815         }
 816
 817         /* Be careful here, modifying NAT bits can screw up things,
 818          * so don't let users modify them directly if they don't pass
 819          * nf_nat_range. */
 820         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 821         return 0;
 822 }
 823
 824
 825 static inline int
 826 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 827 {
 828         struct nf_conntrack_helper *helper;
 829         struct nf_conn_help *help = nfct_help(ct);
 830         char *helpname;
 831         int err;
 832
 833         if (!help) {
 834                 /* FIXME: we need to reallocate and rehash */
 835                 return -EBUSY;
 836         }
 837
 838         /* don't change helper of sibling connections */
 839         if (ct->master)
 840                 return -EINVAL;
 841
 842         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 843         if (err < 0)
 844                 return err;
 845
 846         helper = __nf_conntrack_helper_find_byname(helpname);
 847         if (!helper) {
 848                 if (!strcmp(helpname, ""))
 849                         helper = NULL;
 850                 else
 851                         return -EINVAL;
 852         }
 853
 854         if (help->helper) {
 855                 if (!helper) {
 856                         /* we had a helper before ... */
 857                         nf_ct_remove_expectations(ct);
 858                         help->helper = NULL;
 859                 } else {
 860                         /* need to zero data of old helper */
 861                         memset(&help->help, 0, sizeof(help->help));
 862                 }
 863         }
 864
 865         help->helper = helper;
 866
 867         return 0;
 868 }
 869
 870 static inline int
 871 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 872 {
 873         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 874
 875         if (!del_timer(&ct->timeout))
 876                 return -ETIME;
 877
 878         ct->timeout.expires = jiffies + timeout * HZ;
 879         add_timer(&ct->timeout);
 880
 881         return 0;
 882 }
 883
 884 static inline int
 885 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 886 {
 887         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 888         struct nf_conntrack_l4proto *l4proto;
 889         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 890         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 891         int err = 0;
 892
 893         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 894
 895         l4proto = nf_ct_l4proto_find_get(l3num, npt);
 896
 897         if (l4proto->from_nfattr)
 898                 err = l4proto->from_nfattr(tb, ct);
 899         nf_ct_l4proto_put(l4proto);
 900
 901         return err;
 902 }
 903
 904 static int
 905 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
 906 {
 907         int err;
 908
 909         if (cda[CTA_HELP-1]) {
 910                 err = ctnetlink_change_helper(ct, cda);
 911                 if (err < 0)
 912                         return err;
 913         }
 914
 915         if (cda[CTA_TIMEOUT-1]) {
 916                 err = ctnetlink_change_timeout(ct, cda);
 917                 if (err < 0)
 918                         return err;
 919         }
 920
 921         if (cda[CTA_STATUS-1]) {
 922                 err = ctnetlink_change_status(ct, cda);
 923                 if (err < 0)
 924                         return err;
 925         }
 926
 927         if (cda[CTA_PROTOINFO-1]) {
 928                 err = ctnetlink_change_protoinfo(ct, cda);
 929                 if (err < 0)
 930                         return err;
 931         }
 932
 933 #if defined(CONFIG_NF_CONNTRACK_MARK)
 934         if (cda[CTA_MARK-1])
 935                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 936 #endif
 937
 938         return 0;
 939 }
 940
 941 static int
 942 ctnetlink_create_conntrack(struct nfattr *cda[],
 943                            struct nf_conntrack_tuple *otuple,
 944                            struct nf_conntrack_tuple *rtuple)
 945 {
 946         struct nf_conn *ct;
 947         int err = -EINVAL;
 948         struct nf_conn_help *help;
 949
 950         ct = nf_conntrack_alloc(otuple, rtuple);
 951         if (ct == NULL || IS_ERR(ct))
 952                 return -ENOMEM;
 953
 954         if (!cda[CTA_TIMEOUT-1])
 955                 goto err;
 956         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 957
 958         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
 959         ct->status |= IPS_CONFIRMED;
 960
 961         if (cda[CTA_STATUS-1]) {
 962                 err = ctnetlink_change_status(ct, cda);
 963                 if (err < 0)
 964                         goto err;
 965         }
 966
 967         if (cda[CTA_PROTOINFO-1]) {
 968                 err = ctnetlink_change_protoinfo(ct, cda);
 969                 if (err < 0)
 970                         goto err;
 971         }
 972
 973 #if defined(CONFIG_NF_CONNTRACK_MARK)
 974         if (cda[CTA_MARK-1])
 975                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
 976 #endif
 977
 978         help = nfct_help(ct);
 979         if (help)
 980                 help->helper = nf_ct_helper_find_get(rtuple);
 981
 982         add_timer(&ct->timeout);
 983         nf_conntrack_hash_insert(ct);
 984
 985         if (help && help->helper)
 986                 nf_ct_helper_put(help->helper);
 987
 988         return 0;
 989
 990 err:
 991         nf_conntrack_free(ct);
 992         return err;
 993 }
 994
 995 static int
 996 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
 997                         struct nlmsghdr *nlh, struct nfattr *cda[])
 998 {
 999         struct nf_conntrack_tuple otuple, rtuple;
1000         struct nf_conntrack_tuple_hash *h = NULL;
1001         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1002         u_int8_t u3 = nfmsg->nfgen_family;
1003         int err = 0;
1004
1005         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1006                 return -EINVAL;
1007
1008         if (cda[CTA_TUPLE_ORIG-1]) {
1009                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1010                 if (err < 0)
1011                         return err;
1012         }
1013
1014         if (cda[CTA_TUPLE_REPLY-1]) {
1015                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1016                 if (err < 0)
1017                         return err;
1018         }
1019
1020         write_lock_bh(&nf_conntrack_lock);
1021         if (cda[CTA_TUPLE_ORIG-1])
1022                 h = __nf_conntrack_find(&otuple, NULL);
1023         else if (cda[CTA_TUPLE_REPLY-1])
1024                 h = __nf_conntrack_find(&rtuple, NULL);
1025
1026         if (h == NULL) {
1027                 write_unlock_bh(&nf_conntrack_lock);
1028                 err = -ENOENT;
1029                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1030                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1031                 return err;
1032         }
1033         /* implicit 'else' */
1034
1035         /* we only allow nat config for new conntracks */
1036         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1037                 err = -EINVAL;
1038                 goto out_unlock;
1039         }
1040
1041         /* We manipulate the conntrack inside the global conntrack table lock,
1042          * so there's no need to increase the refcount */
1043         err = -EEXIST;
1044         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1045                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1046
1047 out_unlock:
1048         write_unlock_bh(&nf_conntrack_lock);
1049         return err;
1050 }
1051
1052 /***********************************************************************
1053  * EXPECT
1054  ***********************************************************************/
1055
1056 static inline int
1057 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1058                          const struct nf_conntrack_tuple *tuple,
1059                          enum ctattr_expect type)
1060 {
1061         struct nfattr *nest_parms = NFA_NEST(skb, type);
1062
1063         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1064                 goto nfattr_failure;
1065
1066         NFA_NEST_END(skb, nest_parms);
1067
1068         return 0;
1069
1070 nfattr_failure:
1071         return -1;
1072 }
1073
1074 static inline int
1075 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1076                         const struct nf_conntrack_tuple *tuple,
1077                         const struct nf_conntrack_tuple *mask)
1078 {
1079         int ret;
1080         struct nf_conntrack_l3proto *l3proto;
1081         struct nf_conntrack_l4proto *l4proto;
1082         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1083
1084         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1085         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1086         nf_ct_l3proto_put(l3proto);
1087
1088         if (unlikely(ret < 0))
1089                 goto nfattr_failure;
1090
1091         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1092         ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);
1093         nf_ct_l4proto_put(l4proto);
1094         if (unlikely(ret < 0))
1095                 goto nfattr_failure;
1096
1097         NFA_NEST_END(skb, nest_parms);
1098
1099         return 0;
1100
1101 nfattr_failure:
1102         return -1;
1103 }
1104
1105 static inline int
1106 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1107                           const struct nf_conntrack_expect *exp)
1108 {
1109         struct nf_conn *master = exp->master;
1110         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1111         __be32 id = htonl(exp->id);
1112
1113         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1114                 goto nfattr_failure;
1115         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1116                 goto nfattr_failure;
1117         if (ctnetlink_exp_dump_tuple(skb,
1118                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1119                                  CTA_EXPECT_MASTER) < 0)
1120                 goto nfattr_failure;
1121
1122         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1123         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1124
1125         return 0;
1126
1127 nfattr_failure:
1128         return -1;
1129 }
1130
1131 static int
1132 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1133                     int event,
1134                     int nowait,
1135                     const struct nf_conntrack_expect *exp)
1136 {
1137         struct nlmsghdr *nlh;
1138         struct nfgenmsg *nfmsg;
1139         unsigned char *b = skb_tail_pointer(skb);
1140
1141         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1142         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1143         nfmsg  = NLMSG_DATA(nlh);
1144
1145         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1146         nfmsg->nfgen_family = exp->tuple.src.l3num;
1147         nfmsg->version      = NFNETLINK_V0;
1148         nfmsg->res_id       = 0;
1149
1150         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1151                 goto nfattr_failure;
1152
1153         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1154         return skb->len;
1155
1156 nlmsg_failure:
1157 nfattr_failure:
1158         nlmsg_trim(skb, b);
1159         return -1;
1160 }
1161
1162 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1163 static int ctnetlink_expect_event(struct notifier_block *this,
1164                                   unsigned long events, void *ptr)
1165 {
1166         struct nlmsghdr *nlh;
1167         struct nfgenmsg *nfmsg;
1168         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1169         struct sk_buff *skb;
1170         unsigned int type;
1171         sk_buff_data_t b;
1172         int flags = 0;
1173
1174         if (events & IPEXP_NEW) {
1175                 type = IPCTNL_MSG_EXP_NEW;
1176                 flags = NLM_F_CREATE|NLM_F_EXCL;
1177         } else
1178                 return NOTIFY_DONE;
1179
1180         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1181                 return NOTIFY_DONE;
1182
1183         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1184         if (!skb)
1185                 return NOTIFY_DONE;
1186
1187         b = skb->tail;
1188
1189         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1190         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1191         nfmsg = NLMSG_DATA(nlh);
1192
1193         nlh->nlmsg_flags    = flags;
1194         nfmsg->nfgen_family = exp->tuple.src.l3num;
1195         nfmsg->version      = NFNETLINK_V0;
1196         nfmsg->res_id       = 0;
1197
1198         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1199                 goto nfattr_failure;
1200
1201         nlh->nlmsg_len = skb->tail - b;
1202         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1203         return NOTIFY_DONE;
1204
1205 nlmsg_failure:
1206 nfattr_failure:
1207         kfree_skb(skb);
1208         return NOTIFY_DONE;
1209 }
1210 #endif
1211
1212 static int
1213 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1214 {
1215         struct nf_conntrack_expect *exp = NULL;
1216         struct list_head *i;
1217         u_int32_t *id = (u_int32_t *) &cb->args[0];
1218         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1219         u_int8_t l3proto = nfmsg->nfgen_family;
1220
1221         read_lock_bh(&nf_conntrack_lock);
1222         list_for_each_prev(i, &nf_conntrack_expect_list) {
1223                 exp = (struct nf_conntrack_expect *) i;
1224                 if (l3proto && exp->tuple.src.l3num != l3proto)
1225                         continue;
1226                 if (exp->id <= *id)
1227                         continue;
1228                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1229                                             cb->nlh->nlmsg_seq,
1230                                             IPCTNL_MSG_EXP_NEW,
1231                                             1, exp) < 0)
1232                         goto out;
1233                 *id = exp->id;
1234         }
1235 out:
1236         read_unlock_bh(&nf_conntrack_lock);
1237
1238         return skb->len;
1239 }
1240
1241 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1242         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1243         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1244 };
1245
1246 static int
1247 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1248                      struct nlmsghdr *nlh, struct nfattr *cda[])
1249 {
1250         struct nf_conntrack_tuple tuple;
1251         struct nf_conntrack_expect *exp;
1252         struct sk_buff *skb2;
1253         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1254         u_int8_t u3 = nfmsg->nfgen_family;
1255         int err = 0;
1256
1257         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1258                 return -EINVAL;
1259
1260         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1261                 return netlink_dump_start(ctnl, skb, nlh,
1262                                           ctnetlink_exp_dump_table,
1263                                           ctnetlink_done);
1264         }
1265
1266         if (cda[CTA_EXPECT_MASTER-1])
1267                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1268         else
1269                 return -EINVAL;
1270
1271         if (err < 0)
1272                 return err;
1273
1274         exp = nf_conntrack_expect_find_get(&tuple);
1275         if (!exp)
1276                 return -ENOENT;
1277
1278         if (cda[CTA_EXPECT_ID-1]) {
1279                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1280                 if (exp->id != ntohl(id)) {
1281                         nf_conntrack_expect_put(exp);
1282                         return -ENOENT;
1283                 }
1284         }
1285
1286         err = -ENOMEM;
1287         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1288         if (!skb2)
1289                 goto out;
1290
1291         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1292                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1293                                       1, exp);
1294         if (err <= 0)
1295                 goto free;
1296
1297         nf_conntrack_expect_put(exp);
1298
1299         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1300
1301 free:
1302         kfree_skb(skb2);
1303 out:
1304         nf_conntrack_expect_put(exp);
1305         return err;
1306 }
1307
1308 static int
1309 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1310                      struct nlmsghdr *nlh, struct nfattr *cda[])
1311 {
1312         struct nf_conntrack_expect *exp, *tmp;
1313         struct nf_conntrack_tuple tuple;
1314         struct nf_conntrack_helper *h;
1315         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1316         u_int8_t u3 = nfmsg->nfgen_family;
1317         int err;
1318
1319         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1320                 return -EINVAL;
1321
1322         if (cda[CTA_EXPECT_TUPLE-1]) {
1323                 /* delete a single expect by tuple */
1324                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1325                 if (err < 0)
1326                         return err;
1327
1328                 /* bump usage count to 2 */
1329                 exp = nf_conntrack_expect_find_get(&tuple);
1330                 if (!exp)
1331                         return -ENOENT;
1332
1333                 if (cda[CTA_EXPECT_ID-1]) {
1334                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1335                         if (exp->id != ntohl(id)) {
1336                                 nf_conntrack_expect_put(exp);
1337                                 return -ENOENT;
1338                         }
1339                 }
1340
1341                 /* after list removal, usage count == 1 */
1342                 nf_conntrack_unexpect_related(exp);
1343                 /* have to put what we 'get' above.
1344                  * after this line usage count == 0 */
1345                 nf_conntrack_expect_put(exp);
1346         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1347                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1348
1349                 /* delete all expectations for this helper */
1350                 write_lock_bh(&nf_conntrack_lock);
1351                 h = __nf_conntrack_helper_find_byname(name);
1352                 if (!h) {
1353                         write_unlock_bh(&nf_conntrack_lock);
1354                         return -EINVAL;
1355                 }
1356                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1357                                          list) {
1358                         struct nf_conn_help *m_help = nfct_help(exp->master);
1359                         if (m_help->helper == h
1360                             && del_timer(&exp->timeout)) {
1361                                 nf_ct_unlink_expect(exp);
1362                                 nf_conntrack_expect_put(exp);
1363                         }
1364                 }
1365                 write_unlock_bh(&nf_conntrack_lock);
1366         } else {
1367                 /* This basically means we have to flush everything*/
1368                 write_lock_bh(&nf_conntrack_lock);
1369                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1370                                          list) {
1371                         if (del_timer(&exp->timeout)) {
1372                                 nf_ct_unlink_expect(exp);
1373                                 nf_conntrack_expect_put(exp);
1374                         }
1375                 }
1376                 write_unlock_bh(&nf_conntrack_lock);
1377         }
1378
1379         return 0;
1380 }
1381 static int
1382 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1383 {
1384         return -EOPNOTSUPP;
1385 }
1386
1387 static int
1388 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1389 {
1390         struct nf_conntrack_tuple tuple, mask, master_tuple;
1391         struct nf_conntrack_tuple_hash *h = NULL;
1392         struct nf_conntrack_expect *exp;
1393         struct nf_conn *ct;
1394         struct nf_conn_help *help;
1395         int err = 0;
1396
1397         /* caller guarantees that those three CTA_EXPECT_* exist */
1398         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1399         if (err < 0)
1400                 return err;
1401         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1402         if (err < 0)
1403                 return err;
1404         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1405         if (err < 0)
1406                 return err;
1407
1408         /* Look for master conntrack of this expectation */
1409         h = nf_conntrack_find_get(&master_tuple, NULL);
1410         if (!h)
1411                 return -ENOENT;
1412         ct = nf_ct_tuplehash_to_ctrack(h);
1413         help = nfct_help(ct);
1414
1415         if (!help || !help->helper) {
1416                 /* such conntrack hasn't got any helper, abort */
1417                 err = -EINVAL;
1418                 goto out;
1419         }
1420
1421         exp = nf_conntrack_expect_alloc(ct);
1422         if (!exp) {
1423                 err = -ENOMEM;
1424                 goto out;
1425         }
1426
1427         exp->expectfn = NULL;
1428         exp->flags = 0;
1429         exp->master = ct;
1430         exp->helper = NULL;
1431         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1432         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1433
1434         err = nf_conntrack_expect_related(exp);
1435         nf_conntrack_expect_put(exp);
1436
1437 out:
1438         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1439         return err;
1440 }
1441
1442 static int
1443 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1444                      struct nlmsghdr *nlh, struct nfattr *cda[])
1445 {
1446         struct nf_conntrack_tuple tuple;
1447         struct nf_conntrack_expect *exp;
1448         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1449         u_int8_t u3 = nfmsg->nfgen_family;
1450         int err = 0;
1451
1452         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1453                 return -EINVAL;
1454
1455         if (!cda[CTA_EXPECT_TUPLE-1]
1456             || !cda[CTA_EXPECT_MASK-1]
1457             || !cda[CTA_EXPECT_MASTER-1])
1458                 return -EINVAL;
1459
1460         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1461         if (err < 0)
1462                 return err;
1463
1464         write_lock_bh(&nf_conntrack_lock);
1465         exp = __nf_conntrack_expect_find(&tuple);
1466
1467         if (!exp) {
1468                 write_unlock_bh(&nf_conntrack_lock);
1469                 err = -ENOENT;
1470                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1471                         err = ctnetlink_create_expect(cda, u3);
1472                 return err;
1473         }
1474
1475         err = -EEXIST;
1476         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1477                 err = ctnetlink_change_expect(exp, cda);
1478         write_unlock_bh(&nf_conntrack_lock);
1479
1480         return err;
1481 }
1482
1483 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1484 static struct notifier_block ctnl_notifier = {
1485         .notifier_call  = ctnetlink_conntrack_event,
1486 };
1487
1488 static struct notifier_block ctnl_notifier_exp = {
1489         .notifier_call  = ctnetlink_expect_event,
1490 };
1491 #endif
1492
1493 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1494         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1495                                             .attr_count = CTA_MAX, },
1496         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1497                                             .attr_count = CTA_MAX, },
1498         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1499                                             .attr_count = CTA_MAX, },
1500         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1501                                             .attr_count = CTA_MAX, },
1502 };
1503
1504 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1505         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1506                                             .attr_count = CTA_EXPECT_MAX, },
1507         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1508                                             .attr_count = CTA_EXPECT_MAX, },
1509         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1510                                             .attr_count = CTA_EXPECT_MAX, },
1511 };
1512
1513 static struct nfnetlink_subsystem ctnl_subsys = {
1514         .name                           = "conntrack",
1515         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1516         .cb_count                       = IPCTNL_MSG_MAX,
1517         .cb                             = ctnl_cb,
1518 };
1519
1520 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1521         .name                           = "conntrack_expect",
1522         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1523         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1524         .cb                             = ctnl_exp_cb,
1525 };
1526
1527 MODULE_ALIAS("ip_conntrack_netlink");
1528 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1529 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1530
1531 static int __init ctnetlink_init(void)
1532 {
1533         int ret;
1534
1535         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1536         ret = nfnetlink_subsys_register(&ctnl_subsys);
1537         if (ret < 0) {
1538                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1539                 goto err_out;
1540         }
1541
1542         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1543         if (ret < 0) {
1544                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1545                 goto err_unreg_subsys;
1546         }
1547
1548 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1549         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1550         if (ret < 0) {
1551                 printk("ctnetlink_init: cannot register notifier.\n");
1552                 goto err_unreg_exp_subsys;
1553         }
1554
1555         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1556         if (ret < 0) {
1557                 printk("ctnetlink_init: cannot expect register notifier.\n");
1558                 goto err_unreg_notifier;
1559         }
1560 #endif
1561
1562         return 0;
1563
1564 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1565 err_unreg_notifier:
1566         nf_conntrack_unregister_notifier(&ctnl_notifier);
1567 err_unreg_exp_subsys:
1568         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1569 #endif
1570 err_unreg_subsys:
1571         nfnetlink_subsys_unregister(&ctnl_subsys);
1572 err_out:
1573         return ret;
1574 }
1575
1576 static void __exit ctnetlink_exit(void)
1577 {
1578         printk("ctnetlink: unregistering from nfnetlink.\n");
1579
1580 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1581         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1582         nf_conntrack_unregister_notifier(&ctnl_notifier);
1583 #endif
1584
1585         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1586         nfnetlink_subsys_unregister(&ctnl_subsys);
1587         return;
1588 }
1589
1590 module_init(ctnetlink_init);
1591 module_exit(ctnetlink_exit);