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/notifier.h>
  33
  34 #include <linux/netfilter.h>
  35 #include <net/netfilter/nf_conntrack.h>
  36 #include <net/netfilter/nf_conntrack_core.h>
  37 #include <net/netfilter/nf_conntrack_helper.h>
  38 #include <net/netfilter/nf_conntrack_l3proto.h>
  39 #include <net/netfilter/nf_conntrack_protocol.h>
  40 #include <linux/netfilter_ipv4/ip_nat_protocol.h>
  41
  42 #include <linux/netfilter/nfnetlink.h>
  43 #include <linux/netfilter/nfnetlink_conntrack.h>
  44
  45 MODULE_LICENSE("GPL");
  46
  47 static char __initdata version[] = "0.93";
  48
  49 #if 0
  50 #define DEBUGP printk
  51 #else
  52 #define DEBUGP(format, args...)
  53 #endif
  54
  55
  56 static inline int
  57 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  58                             const struct nf_conntrack_tuple *tuple,
  59                             struct nf_conntrack_protocol *proto)
  60 {
  61         int ret = 0;
  62         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  63
  64         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  65
  66         if (likely(proto->tuple_to_nfattr))
  67                 ret = proto->tuple_to_nfattr(skb, tuple);
  68
  69         NFA_NEST_END(skb, nest_parms);
  70
  71         return ret;
  72
  73 nfattr_failure:
  74         return -1;
  75 }
  76
  77 static inline int
  78 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  79                          const struct nf_conntrack_tuple *tuple,
  80                          struct nf_conntrack_l3proto *l3proto)
  81 {
  82         int ret = 0;
  83         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  84
  85         if (likely(l3proto->tuple_to_nfattr))
  86                 ret = l3proto->tuple_to_nfattr(skb, tuple);
  87
  88         NFA_NEST_END(skb, nest_parms);
  89
  90         return ret;
  91
  92 nfattr_failure:
  93         return -1;
  94 }
  95
  96 static inline int
  97 ctnetlink_dump_tuples(struct sk_buff *skb,
  98                       const struct nf_conntrack_tuple *tuple)
  99 {
 100         int ret;
 101         struct nf_conntrack_l3proto *l3proto;
 102         struct nf_conntrack_protocol *proto;
 103
 104         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 105         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 106         nf_ct_l3proto_put(l3proto);
 107
 108         if (unlikely(ret < 0))
 109                 return ret;
 110
 111         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 112         ret = ctnetlink_dump_tuples_proto(skb, tuple, proto);
 113         nf_ct_proto_put(proto);
 114
 115         return ret;
 116 }
 117
 118 static inline int
 119 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 120 {
 121         u_int32_t status = htonl((u_int32_t) ct->status);
 122         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 123         return 0;
 124
 125 nfattr_failure:
 126         return -1;
 127 }
 128
 129 static inline int
 130 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 131 {
 132         long timeout_l = ct->timeout.expires - jiffies;
 133         u_int32_t timeout;
 134
 135         if (timeout_l < 0)
 136                 timeout = 0;
 137         else
 138                 timeout = htonl(timeout_l / HZ);
 139
 140         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 141         return 0;
 142
 143 nfattr_failure:
 144         return -1;
 145 }
 146
 147 static inline int
 148 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 149 {
 150         struct nf_conntrack_protocol *proto = nf_ct_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 151         struct nfattr *nest_proto;
 152         int ret;
 153
 154         if (!proto->to_nfattr) {
 155                 nf_ct_proto_put(proto);
 156                 return 0;
 157         }
 158
 159         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 160
 161         ret = proto->to_nfattr(skb, nest_proto, ct);
 162
 163         nf_ct_proto_put(proto);
 164
 165         NFA_NEST_END(skb, nest_proto);
 166
 167         return ret;
 168
 169 nfattr_failure:
 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         u_int32_t 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         u_int32_t 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         u_int32_t 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         u_int32_t 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                 /* dump everything */
 339                 events = ~0UL;
 340                 group = NFNLGRP_CONNTRACK_NEW;
 341         } else  if (events & (IPCT_STATUS |
 342                       IPCT_PROTOINFO |
 343                       IPCT_HELPER |
 344                       IPCT_HELPINFO |
 345                       IPCT_NATINFO)) {
 346                 type = IPCTNL_MSG_CT_NEW;
 347                 group = NFNLGRP_CONNTRACK_UPDATE;
 348         } else
 349                 return NOTIFY_DONE;
 350
 351         if (!nfnetlink_has_listeners(group))
 352                 return NOTIFY_DONE;
 353
 354         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 355         if (!skb)
 356                 return NOTIFY_DONE;
 357
 358         b = skb->tail;
 359
 360         type |= NFNL_SUBSYS_CTNETLINK << 8;
 361         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 362         nfmsg = NLMSG_DATA(nlh);
 363
 364         nlh->nlmsg_flags    = flags;
 365         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 366         nfmsg->version  = NFNETLINK_V0;
 367         nfmsg->res_id   = 0;
 368
 369         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 370         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 371                 goto nfattr_failure;
 372         NFA_NEST_END(skb, nest_parms);
 373
 374         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 375         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 376                 goto nfattr_failure;
 377         NFA_NEST_END(skb, nest_parms);
 378
 379         /* NAT stuff is now a status flag */
 380         if ((events & IPCT_STATUS || events & IPCT_NATINFO)
 381             && ctnetlink_dump_status(skb, ct) < 0)
 382                 goto nfattr_failure;
 383         if (events & IPCT_REFRESH
 384             && ctnetlink_dump_timeout(skb, ct) < 0)
 385                 goto nfattr_failure;
 386         if (events & IPCT_PROTOINFO
 387             && ctnetlink_dump_protoinfo(skb, ct) < 0)
 388                 goto nfattr_failure;
 389         if (events & IPCT_HELPINFO
 390             && ctnetlink_dump_helpinfo(skb, ct) < 0)
 391                 goto nfattr_failure;
 392
 393         if (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         nlh->nlmsg_len = skb->tail - b;
 398         nfnetlink_send(skb, 0, group, 0);
 399         return NOTIFY_DONE;
 400
 401 nlmsg_failure:
 402 nfattr_failure:
 403         kfree_skb(skb);
 404         return NOTIFY_DONE;
 405 }
 406 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 407
 408 static int ctnetlink_done(struct netlink_callback *cb)
 409 {
 410         if (cb->args[1])
 411                 nf_ct_put((struct nf_conn *)cb->args[1]);
 412         DEBUGP("entered %s\n", __FUNCTION__);
 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         DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__,
 428                         cb->args[0], *id);
 429
 430         read_lock_bh(&nf_conntrack_lock);
 431         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
 432 restart:
 433                 last = (struct nf_conn *)cb->args[1];
 434                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 435                         h = (struct nf_conntrack_tuple_hash *) i;
 436                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 437                                 continue;
 438                         ct = nf_ct_tuplehash_to_ctrack(h);
 439                         /* Dump entries of a given L3 protocol number.
 440                          * If it is not specified, ie. l3proto == 0,
 441                          * then dump everything. */
 442                         if (l3proto && L3PROTO(ct) != l3proto)
 443                                 continue;
 444                         if (last != NULL) {
 445                                 if (ct == last) {
 446                                         nf_ct_put(last);
 447                                         cb->args[1] = 0;
 448                                         last = NULL;
 449                                 } else
 450                                         continue;
 451                         }
 452                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 453                                                 cb->nlh->nlmsg_seq,
 454                                                 IPCTNL_MSG_CT_NEW,
 455                                                 1, ct) < 0) {
 456                                 nf_conntrack_get(&ct->ct_general);
 457                                 cb->args[1] = (unsigned long)ct;
 458                                 goto out;
 459                         }
 460                 }
 461                 if (last != NULL) {
 462                         nf_ct_put(last);
 463                         cb->args[1] = 0;
 464                         goto restart;
 465                 }
 466         }
 467 out:
 468         read_unlock_bh(&nf_conntrack_lock);
 469
 470         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 471
 472         return skb->len;
 473 }
 474
 475 #ifdef CONFIG_NF_CT_ACCT
 476 static int
 477 ctnetlink_dump_table_w(struct sk_buff *skb, struct netlink_callback *cb)
 478 {
 479         struct nf_conn *ct = NULL;
 480         struct nf_conntrack_tuple_hash *h;
 481         struct list_head *i;
 482         u_int32_t *id = (u_int32_t *) &cb->args[1];
 483         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 484         u_int8_t l3proto = nfmsg->nfgen_family;
 485
 486         DEBUGP("entered %s, last bucket=%u id=%u\n", __FUNCTION__,
 487                         cb->args[0], *id);
 488
 489         write_lock_bh(&nf_conntrack_lock);
 490         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 491                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 492                         h = (struct nf_conntrack_tuple_hash *) i;
 493                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 494                                 continue;
 495                         ct = nf_ct_tuplehash_to_ctrack(h);
 496                         if (l3proto && L3PROTO(ct) != l3proto)
 497                                 continue;
 498                         if (ct->id <= *id)
 499                                 continue;
 500                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 501                                                 cb->nlh->nlmsg_seq,
 502                                                 IPCTNL_MSG_CT_NEW,
 503                                                 1, ct) < 0)
 504                                 goto out;
 505                         *id = ct->id;
 506
 507                         memset(&ct->counters, 0, sizeof(ct->counters));
 508                 }
 509         }
 510 out:
 511         write_unlock_bh(&nf_conntrack_lock);
 512
 513         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 514
 515         return skb->len;
 516 }
 517 #endif
 518
 519 static inline int
 520 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 521 {
 522         struct nfattr *tb[CTA_IP_MAX];
 523         struct nf_conntrack_l3proto *l3proto;
 524         int ret = 0;
 525
 526         DEBUGP("entered %s\n", __FUNCTION__);
 527
 528         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 529
 530         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 531
 532         if (likely(l3proto->nfattr_to_tuple))
 533                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 534
 535         nf_ct_l3proto_put(l3proto);
 536
 537         DEBUGP("leaving\n");
 538
 539         return ret;
 540 }
 541
 542 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 543         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 544 };
 545
 546 static inline int
 547 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 548                             struct nf_conntrack_tuple *tuple)
 549 {
 550         struct nfattr *tb[CTA_PROTO_MAX];
 551         struct nf_conntrack_protocol *proto;
 552         int ret = 0;
 553
 554         DEBUGP("entered %s\n", __FUNCTION__);
 555
 556         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 557
 558         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 559                 return -EINVAL;
 560
 561         if (!tb[CTA_PROTO_NUM-1])
 562                 return -EINVAL;
 563         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 564
 565         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 566
 567         if (likely(proto->nfattr_to_tuple))
 568                 ret = proto->nfattr_to_tuple(tb, tuple);
 569
 570         nf_ct_proto_put(proto);
 571
 572         return ret;
 573 }
 574
 575 static inline int
 576 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 577                       enum ctattr_tuple type, u_int8_t l3num)
 578 {
 579         struct nfattr *tb[CTA_TUPLE_MAX];
 580         int err;
 581
 582         DEBUGP("entered %s\n", __FUNCTION__);
 583
 584         memset(tuple, 0, sizeof(*tuple));
 585
 586         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 587
 588         if (!tb[CTA_TUPLE_IP-1])
 589                 return -EINVAL;
 590
 591         tuple->src.l3num = l3num;
 592
 593         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 594         if (err < 0)
 595                 return err;
 596
 597         if (!tb[CTA_TUPLE_PROTO-1])
 598                 return -EINVAL;
 599
 600         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 601         if (err < 0)
 602                 return err;
 603
 604         /* orig and expect tuples get DIR_ORIGINAL */
 605         if (type == CTA_TUPLE_REPLY)
 606                 tuple->dst.dir = IP_CT_DIR_REPLY;
 607         else
 608                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 609
 610         NF_CT_DUMP_TUPLE(tuple);
 611
 612         DEBUGP("leaving\n");
 613
 614         return 0;
 615 }
 616
 617 #ifdef CONFIG_IP_NF_NAT_NEEDED
 618 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 619         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 620         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 621 };
 622
 623 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 624                                      const struct nf_conn *ct,
 625                                      struct ip_nat_range *range)
 626 {
 627         struct nfattr *tb[CTA_PROTONAT_MAX];
 628         struct ip_nat_protocol *npt;
 629
 630         DEBUGP("entered %s\n", __FUNCTION__);
 631
 632         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 633
 634         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 635                 return -EINVAL;
 636
 637         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 638
 639         if (!npt->nfattr_to_range) {
 640                 ip_nat_proto_put(npt);
 641                 return 0;
 642         }
 643
 644         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 645         if (npt->nfattr_to_range(tb, range) > 0)
 646                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 647
 648         ip_nat_proto_put(npt);
 649
 650         DEBUGP("leaving\n");
 651         return 0;
 652 }
 653
 654 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 655         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 656         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 657 };
 658
 659 static inline int
 660 ctnetlink_parse_nat(struct nfattr *nat,
 661                     const struct nf_conn *ct, struct ip_nat_range *range)
 662 {
 663         struct nfattr *tb[CTA_NAT_MAX];
 664         int err;
 665
 666         DEBUGP("entered %s\n", __FUNCTION__);
 667
 668         memset(range, 0, sizeof(*range));
 669
 670         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 671
 672         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 673                 return -EINVAL;
 674
 675         if (tb[CTA_NAT_MINIP-1])
 676                 range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 677
 678         if (!tb[CTA_NAT_MAXIP-1])
 679                 range->max_ip = range->min_ip;
 680         else
 681                 range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 682
 683         if (range->min_ip)
 684                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 685
 686         if (!tb[CTA_NAT_PROTO-1])
 687                 return 0;
 688
 689         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 690         if (err < 0)
 691                 return err;
 692
 693         DEBUGP("leaving\n");
 694         return 0;
 695 }
 696 #endif
 697
 698 static inline int
 699 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 700 {
 701         struct nfattr *tb[CTA_HELP_MAX];
 702
 703         DEBUGP("entered %s\n", __FUNCTION__);
 704
 705         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 706
 707         if (!tb[CTA_HELP_NAME-1])
 708                 return -EINVAL;
 709
 710         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 711
 712         return 0;
 713 }
 714
 715 static const size_t cta_min[CTA_MAX] = {
 716         [CTA_STATUS-1]          = sizeof(u_int32_t),
 717         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 718         [CTA_MARK-1]            = sizeof(u_int32_t),
 719         [CTA_USE-1]             = sizeof(u_int32_t),
 720         [CTA_ID-1]              = sizeof(u_int32_t)
 721 };
 722
 723 static int
 724 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 725                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 726 {
 727         struct nf_conntrack_tuple_hash *h;
 728         struct nf_conntrack_tuple tuple;
 729         struct nf_conn *ct;
 730         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 731         u_int8_t u3 = nfmsg->nfgen_family;
 732         int err = 0;
 733
 734         DEBUGP("entered %s\n", __FUNCTION__);
 735
 736         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 737                 return -EINVAL;
 738
 739         if (cda[CTA_TUPLE_ORIG-1])
 740                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 741         else if (cda[CTA_TUPLE_REPLY-1])
 742                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 743         else {
 744                 /* Flush the whole table */
 745                 nf_conntrack_flush();
 746                 return 0;
 747         }
 748
 749         if (err < 0)
 750                 return err;
 751
 752         h = nf_conntrack_find_get(&tuple, NULL);
 753         if (!h) {
 754                 DEBUGP("tuple not found in conntrack hash\n");
 755                 return -ENOENT;
 756         }
 757
 758         ct = nf_ct_tuplehash_to_ctrack(h);
 759
 760         if (cda[CTA_ID-1]) {
 761                 u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1]));
 762                 if (ct->id != id) {
 763                         nf_ct_put(ct);
 764                         return -ENOENT;
 765                 }
 766         }
 767         if (del_timer(&ct->timeout))
 768                 ct->timeout.function((unsigned long)ct);
 769
 770         nf_ct_put(ct);
 771         DEBUGP("leaving\n");
 772
 773         return 0;
 774 }
 775
 776 static int
 777 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 778                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 779 {
 780         struct nf_conntrack_tuple_hash *h;
 781         struct nf_conntrack_tuple tuple;
 782         struct nf_conn *ct;
 783         struct sk_buff *skb2 = NULL;
 784         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 785         u_int8_t u3 = nfmsg->nfgen_family;
 786         int err = 0;
 787
 788         DEBUGP("entered %s\n", __FUNCTION__);
 789
 790         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 791                 u32 rlen;
 792
 793                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) ==
 794                                         IPCTNL_MSG_CT_GET_CTRZERO) {
 795 #ifdef CONFIG_NF_CT_ACCT
 796                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 797                                                 ctnetlink_dump_table_w,
 798                                                 ctnetlink_done)) != 0)
 799                                 return -EINVAL;
 800 #else
 801                         return -ENOTSUPP;
 802 #endif
 803                 } else {
 804                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 805                                                         ctnetlink_dump_table,
 806                                                         ctnetlink_done)) != 0)
 807                         return -EINVAL;
 808                 }
 809
 810                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 811                 if (rlen > skb->len)
 812                         rlen = skb->len;
 813                 skb_pull(skb, rlen);
 814                 return 0;
 815         }
 816
 817         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 818                 return -EINVAL;
 819
 820         if (cda[CTA_TUPLE_ORIG-1])
 821                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 822         else if (cda[CTA_TUPLE_REPLY-1])
 823                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 824         else
 825                 return -EINVAL;
 826
 827         if (err < 0)
 828                 return err;
 829
 830         h = nf_conntrack_find_get(&tuple, NULL);
 831         if (!h) {
 832                 DEBUGP("tuple not found in conntrack hash");
 833                 return -ENOENT;
 834         }
 835         DEBUGP("tuple found\n");
 836         ct = nf_ct_tuplehash_to_ctrack(h);
 837
 838         err = -ENOMEM;
 839         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 840         if (!skb2) {
 841                 nf_ct_put(ct);
 842                 return -ENOMEM;
 843         }
 844         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
 845
 846         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 847                                   IPCTNL_MSG_CT_NEW, 1, ct);
 848         nf_ct_put(ct);
 849         if (err <= 0)
 850                 goto free;
 851
 852         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 853         if (err < 0)
 854                 goto out;
 855
 856         DEBUGP("leaving\n");
 857         return 0;
 858
 859 free:
 860         kfree_skb(skb2);
 861 out:
 862         return err;
 863 }
 864
 865 static inline int
 866 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 867 {
 868         unsigned long d;
 869         unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1]));
 870         d = ct->status ^ status;
 871
 872         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 873                 /* unchangeable */
 874                 return -EINVAL;
 875
 876         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 877                 /* SEEN_REPLY bit can only be set */
 878                 return -EINVAL;
 879
 880
 881         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 882                 /* ASSURED bit can only be set */
 883                 return -EINVAL;
 884
 885         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 886 #ifndef CONFIG_IP_NF_NAT_NEEDED
 887                 return -EINVAL;
 888 #else
 889                 struct ip_nat_range range;
 890
 891                 if (cda[CTA_NAT_DST-1]) {
 892                         if (ctnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 893                                                 &range) < 0)
 894                                 return -EINVAL;
 895                         if (ip_nat_initialized(ct,
 896                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 897                                 return -EEXIST;
 898                         ip_nat_setup_info(ct, &range, hooknum);
 899                 }
 900                 if (cda[CTA_NAT_SRC-1]) {
 901                         if (ctnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 902                                                 &range) < 0)
 903                                 return -EINVAL;
 904                         if (ip_nat_initialized(ct,
 905                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 906                                 return -EEXIST;
 907                         ip_nat_setup_info(ct, &range, hooknum);
 908                 }
 909 #endif
 910         }
 911
 912         /* Be careful here, modifying NAT bits can screw up things,
 913          * so don't let users modify them directly if they don't pass
 914          * ip_nat_range. */
 915         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 916         return 0;
 917 }
 918
 919
 920 static inline int
 921 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 922 {
 923         struct nf_conntrack_helper *helper;
 924         struct nf_conn_help *help = nfct_help(ct);
 925         char *helpname;
 926         int err;
 927
 928         DEBUGP("entered %s\n", __FUNCTION__);
 929
 930         if (!help) {
 931                 /* FIXME: we need to reallocate and rehash */
 932                 return -EBUSY;
 933         }
 934
 935         /* don't change helper of sibling connections */
 936         if (ct->master)
 937                 return -EINVAL;
 938
 939         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 940         if (err < 0)
 941                 return err;
 942
 943         helper = __nf_conntrack_helper_find_byname(helpname);
 944         if (!helper) {
 945                 if (!strcmp(helpname, ""))
 946                         helper = NULL;
 947                 else
 948                         return -EINVAL;
 949         }
 950
 951         if (help->helper) {
 952                 if (!helper) {
 953                         /* we had a helper before ... */
 954                         nf_ct_remove_expectations(ct);
 955                         help->helper = NULL;
 956                 } else {
 957                         /* need to zero data of old helper */
 958                         memset(&help->help, 0, sizeof(help->help));
 959                 }
 960         }
 961
 962         help->helper = helper;
 963
 964         return 0;
 965 }
 966
 967 static inline int
 968 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 969 {
 970         u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 971
 972         if (!del_timer(&ct->timeout))
 973                 return -ETIME;
 974
 975         ct->timeout.expires = jiffies + timeout * HZ;
 976         add_timer(&ct->timeout);
 977
 978         return 0;
 979 }
 980
 981 static inline int
 982 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 983 {
 984         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 985         struct nf_conntrack_protocol *proto;
 986         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 987         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 988         int err = 0;
 989
 990         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 991
 992         proto = nf_ct_proto_find_get(l3num, npt);
 993
 994         if (proto->from_nfattr)
 995                 err = proto->from_nfattr(tb, ct);
 996         nf_ct_proto_put(proto);
 997
 998         return err;
 999 }
1000
1001 static int
1002 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
1003 {
1004         int err;
1005
1006         DEBUGP("entered %s\n", __FUNCTION__);
1007
1008         if (cda[CTA_HELP-1]) {
1009                 err = ctnetlink_change_helper(ct, cda);
1010                 if (err < 0)
1011                         return err;
1012         }
1013
1014         if (cda[CTA_TIMEOUT-1]) {
1015                 err = ctnetlink_change_timeout(ct, cda);
1016                 if (err < 0)
1017                         return err;
1018         }
1019
1020         if (cda[CTA_STATUS-1]) {
1021                 err = ctnetlink_change_status(ct, cda);
1022                 if (err < 0)
1023                         return err;
1024         }
1025
1026         if (cda[CTA_PROTOINFO-1]) {
1027                 err = ctnetlink_change_protoinfo(ct, cda);
1028                 if (err < 0)
1029                         return err;
1030         }
1031
1032 #if defined(CONFIG_NF_CONNTRACK_MARK)
1033         if (cda[CTA_MARK-1])
1034                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1035 #endif
1036
1037         DEBUGP("all done\n");
1038         return 0;
1039 }
1040
1041 static int
1042 ctnetlink_create_conntrack(struct nfattr *cda[],
1043                            struct nf_conntrack_tuple *otuple,
1044                            struct nf_conntrack_tuple *rtuple)
1045 {
1046         struct nf_conn *ct;
1047         int err = -EINVAL;
1048
1049         DEBUGP("entered %s\n", __FUNCTION__);
1050
1051         ct = nf_conntrack_alloc(otuple, rtuple);
1052         if (ct == NULL || IS_ERR(ct))
1053                 return -ENOMEM;
1054
1055         if (!cda[CTA_TIMEOUT-1])
1056                 goto err;
1057         ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
1058
1059         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1060         ct->status |= IPS_CONFIRMED;
1061
1062         err = ctnetlink_change_status(ct, cda);
1063         if (err < 0)
1064                 goto err;
1065
1066         if (cda[CTA_PROTOINFO-1]) {
1067                 err = ctnetlink_change_protoinfo(ct, cda);
1068                 if (err < 0)
1069                         return err;
1070         }
1071
1072 #if defined(CONFIG_NF_CONNTRACK_MARK)
1073         if (cda[CTA_MARK-1])
1074                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1075 #endif
1076
1077         add_timer(&ct->timeout);
1078         nf_conntrack_hash_insert(ct);
1079
1080         DEBUGP("conntrack with id %u inserted\n", ct->id);
1081         return 0;
1082
1083 err:
1084         nf_conntrack_free(ct);
1085         return err;
1086 }
1087
1088 static int
1089 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1090                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1091 {
1092         struct nf_conntrack_tuple otuple, rtuple;
1093         struct nf_conntrack_tuple_hash *h = NULL;
1094         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1095         u_int8_t u3 = nfmsg->nfgen_family;
1096         int err = 0;
1097
1098         DEBUGP("entered %s\n", __FUNCTION__);
1099
1100         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1101                 return -EINVAL;
1102
1103         if (cda[CTA_TUPLE_ORIG-1]) {
1104                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1105                 if (err < 0)
1106                         return err;
1107         }
1108
1109         if (cda[CTA_TUPLE_REPLY-1]) {
1110                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1111                 if (err < 0)
1112                         return err;
1113         }
1114
1115         write_lock_bh(&nf_conntrack_lock);
1116         if (cda[CTA_TUPLE_ORIG-1])
1117                 h = __nf_conntrack_find(&otuple, NULL);
1118         else if (cda[CTA_TUPLE_REPLY-1])
1119                 h = __nf_conntrack_find(&rtuple, NULL);
1120
1121         if (h == NULL) {
1122                 write_unlock_bh(&nf_conntrack_lock);
1123                 DEBUGP("no such conntrack, create new\n");
1124                 err = -ENOENT;
1125                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1126                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1127                 return err;
1128         }
1129         /* implicit 'else' */
1130
1131         /* we only allow nat config for new conntracks */
1132         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1133                 err = -EINVAL;
1134                 goto out_unlock;
1135         }
1136
1137         /* We manipulate the conntrack inside the global conntrack table lock,
1138          * so there's no need to increase the refcount */
1139         DEBUGP("conntrack found\n");
1140         err = -EEXIST;
1141         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1142                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1143
1144 out_unlock:
1145         write_unlock_bh(&nf_conntrack_lock);
1146         return err;
1147 }
1148
1149 /***********************************************************************
1150  * EXPECT
1151  ***********************************************************************/
1152
1153 static inline int
1154 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1155                          const struct nf_conntrack_tuple *tuple,
1156                          enum ctattr_expect type)
1157 {
1158         struct nfattr *nest_parms = NFA_NEST(skb, type);
1159
1160         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1161                 goto nfattr_failure;
1162
1163         NFA_NEST_END(skb, nest_parms);
1164
1165         return 0;
1166
1167 nfattr_failure:
1168         return -1;
1169 }
1170
1171 static inline int
1172 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1173                         const struct nf_conntrack_tuple *tuple,
1174                         const struct nf_conntrack_tuple *mask)
1175 {
1176         int ret;
1177         struct nf_conntrack_l3proto *l3proto;
1178         struct nf_conntrack_protocol *proto;
1179         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1180
1181         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1182         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1183         nf_ct_l3proto_put(l3proto);
1184
1185         if (unlikely(ret < 0))
1186                 goto nfattr_failure;
1187
1188         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1189         ret = ctnetlink_dump_tuples_proto(skb, mask, proto);
1190         nf_ct_proto_put(proto);
1191         if (unlikely(ret < 0))
1192                 goto nfattr_failure;
1193
1194         NFA_NEST_END(skb, nest_parms);
1195
1196         return 0;
1197
1198 nfattr_failure:
1199         return -1;
1200 }
1201
1202 static inline int
1203 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1204                           const struct nf_conntrack_expect *exp)
1205 {
1206         struct nf_conn *master = exp->master;
1207         u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1208         u_int32_t id = htonl(exp->id);
1209
1210         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1211                 goto nfattr_failure;
1212         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1213                 goto nfattr_failure;
1214         if (ctnetlink_exp_dump_tuple(skb,
1215                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1216                                  CTA_EXPECT_MASTER) < 0)
1217                 goto nfattr_failure;
1218
1219         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1220         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1221
1222         return 0;
1223
1224 nfattr_failure:
1225         return -1;
1226 }
1227
1228 static int
1229 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1230                     int event,
1231                     int nowait,
1232                     const struct nf_conntrack_expect *exp)
1233 {
1234         struct nlmsghdr *nlh;
1235         struct nfgenmsg *nfmsg;
1236         unsigned char *b;
1237
1238         b = skb->tail;
1239
1240         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1241         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1242         nfmsg  = NLMSG_DATA(nlh);
1243
1244         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1245         nfmsg->nfgen_family = exp->tuple.src.l3num;
1246         nfmsg->version      = NFNETLINK_V0;
1247         nfmsg->res_id       = 0;
1248
1249         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1250                 goto nfattr_failure;
1251
1252         nlh->nlmsg_len = skb->tail - b;
1253         return skb->len;
1254
1255 nlmsg_failure:
1256 nfattr_failure:
1257         skb_trim(skb, b - skb->data);
1258         return -1;
1259 }
1260
1261 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1262 static int ctnetlink_expect_event(struct notifier_block *this,
1263                                   unsigned long events, void *ptr)
1264 {
1265         struct nlmsghdr *nlh;
1266         struct nfgenmsg *nfmsg;
1267         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1268         struct sk_buff *skb;
1269         unsigned int type;
1270         unsigned char *b;
1271         int flags = 0;
1272
1273         if (events & IPEXP_NEW) {
1274                 type = IPCTNL_MSG_EXP_NEW;
1275                 flags = NLM_F_CREATE|NLM_F_EXCL;
1276         } else
1277                 return NOTIFY_DONE;
1278
1279         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1280         if (!skb)
1281                 return NOTIFY_DONE;
1282
1283         b = skb->tail;
1284
1285         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1286         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1287         nfmsg = NLMSG_DATA(nlh);
1288
1289         nlh->nlmsg_flags    = flags;
1290         nfmsg->nfgen_family = exp->tuple.src.l3num;
1291         nfmsg->version      = NFNETLINK_V0;
1292         nfmsg->res_id       = 0;
1293
1294         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1295                 goto nfattr_failure;
1296
1297         nlh->nlmsg_len = skb->tail - b;
1298         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1299         return NOTIFY_DONE;
1300
1301 nlmsg_failure:
1302 nfattr_failure:
1303         kfree_skb(skb);
1304         return NOTIFY_DONE;
1305 }
1306 #endif
1307
1308 static int
1309 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1310 {
1311         struct nf_conntrack_expect *exp = NULL;
1312         struct list_head *i;
1313         u_int32_t *id = (u_int32_t *) &cb->args[0];
1314         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1315         u_int8_t l3proto = nfmsg->nfgen_family;
1316
1317         DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id);
1318
1319         read_lock_bh(&nf_conntrack_lock);
1320         list_for_each_prev(i, &nf_conntrack_expect_list) {
1321                 exp = (struct nf_conntrack_expect *) i;
1322                 if (l3proto && exp->tuple.src.l3num != l3proto)
1323                         continue;
1324                 if (exp->id <= *id)
1325                         continue;
1326                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1327                                             cb->nlh->nlmsg_seq,
1328                                             IPCTNL_MSG_EXP_NEW,
1329                                             1, exp) < 0)
1330                         goto out;
1331                 *id = exp->id;
1332         }
1333 out:
1334         read_unlock_bh(&nf_conntrack_lock);
1335
1336         DEBUGP("leaving, last id=%llu\n", *id);
1337
1338         return skb->len;
1339 }
1340
1341 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1342         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1343         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1344 };
1345
1346 static int
1347 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1348                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1349 {
1350         struct nf_conntrack_tuple tuple;
1351         struct nf_conntrack_expect *exp;
1352         struct sk_buff *skb2;
1353         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1354         u_int8_t u3 = nfmsg->nfgen_family;
1355         int err = 0;
1356
1357         DEBUGP("entered %s\n", __FUNCTION__);
1358
1359         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1360                 return -EINVAL;
1361
1362         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1363                 u32 rlen;
1364
1365                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1366                                                 ctnetlink_exp_dump_table,
1367                                                 ctnetlink_done)) != 0)
1368                         return -EINVAL;
1369                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1370                 if (rlen > skb->len)
1371                         rlen = skb->len;
1372                 skb_pull(skb, rlen);
1373                 return 0;
1374         }
1375
1376         if (cda[CTA_EXPECT_MASTER-1])
1377                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1378         else
1379                 return -EINVAL;
1380
1381         if (err < 0)
1382                 return err;
1383
1384         exp = nf_conntrack_expect_find(&tuple);
1385         if (!exp)
1386                 return -ENOENT;
1387
1388         if (cda[CTA_EXPECT_ID-1]) {
1389                 u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1390                 if (exp->id != ntohl(id)) {
1391                         nf_conntrack_expect_put(exp);
1392                         return -ENOENT;
1393                 }
1394         }
1395
1396         err = -ENOMEM;
1397         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1398         if (!skb2)
1399                 goto out;
1400         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
1401
1402         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1403                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1404                                       1, exp);
1405         if (err <= 0)
1406                 goto free;
1407
1408         nf_conntrack_expect_put(exp);
1409
1410         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1411
1412 free:
1413         kfree_skb(skb2);
1414 out:
1415         nf_conntrack_expect_put(exp);
1416         return err;
1417 }
1418
1419 static int
1420 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1421                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1422 {
1423         struct nf_conntrack_expect *exp, *tmp;
1424         struct nf_conntrack_tuple tuple;
1425         struct nf_conntrack_helper *h;
1426         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1427         u_int8_t u3 = nfmsg->nfgen_family;
1428         int err;
1429
1430         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1431                 return -EINVAL;
1432
1433         if (cda[CTA_EXPECT_TUPLE-1]) {
1434                 /* delete a single expect by tuple */
1435                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1436                 if (err < 0)
1437                         return err;
1438
1439                 /* bump usage count to 2 */
1440                 exp = nf_conntrack_expect_find(&tuple);
1441                 if (!exp)
1442                         return -ENOENT;
1443
1444                 if (cda[CTA_EXPECT_ID-1]) {
1445                         u_int32_t id =
1446                                 *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1447                         if (exp->id != ntohl(id)) {
1448                                 nf_conntrack_expect_put(exp);
1449                                 return -ENOENT;
1450                         }
1451                 }
1452
1453                 /* after list removal, usage count == 1 */
1454                 nf_conntrack_unexpect_related(exp);
1455                 /* have to put what we 'get' above.
1456                  * after this line usage count == 0 */
1457                 nf_conntrack_expect_put(exp);
1458         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1459                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1460
1461                 /* delete all expectations for this helper */
1462                 write_lock_bh(&nf_conntrack_lock);
1463                 h = __nf_conntrack_helper_find_byname(name);
1464                 if (!h) {
1465                         write_unlock_bh(&nf_conntrack_lock);
1466                         return -EINVAL;
1467                 }
1468                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1469                                          list) {
1470                         struct nf_conn_help *m_help = nfct_help(exp->master);
1471                         if (m_help->helper == h
1472                             && del_timer(&exp->timeout)) {
1473                                 nf_ct_unlink_expect(exp);
1474                                 nf_conntrack_expect_put(exp);
1475                         }
1476                 }
1477                 write_unlock_bh(&nf_conntrack_lock);
1478         } else {
1479                 /* This basically means we have to flush everything*/
1480                 write_lock_bh(&nf_conntrack_lock);
1481                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1482                                          list) {
1483                         if (del_timer(&exp->timeout)) {
1484                                 nf_ct_unlink_expect(exp);
1485                                 nf_conntrack_expect_put(exp);
1486                         }
1487                 }
1488                 write_unlock_bh(&nf_conntrack_lock);
1489         }
1490
1491         return 0;
1492 }
1493 static int
1494 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1495 {
1496         return -EOPNOTSUPP;
1497 }
1498
1499 static int
1500 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1501 {
1502         struct nf_conntrack_tuple tuple, mask, master_tuple;
1503         struct nf_conntrack_tuple_hash *h = NULL;
1504         struct nf_conntrack_expect *exp;
1505         struct nf_conn *ct;
1506         struct nf_conn_help *help;
1507         int err = 0;
1508
1509         DEBUGP("entered %s\n", __FUNCTION__);
1510
1511         /* caller guarantees that those three CTA_EXPECT_* exist */
1512         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1513         if (err < 0)
1514                 return err;
1515         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1516         if (err < 0)
1517                 return err;
1518         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1519         if (err < 0)
1520                 return err;
1521
1522         /* Look for master conntrack of this expectation */
1523         h = nf_conntrack_find_get(&master_tuple, NULL);
1524         if (!h)
1525                 return -ENOENT;
1526         ct = nf_ct_tuplehash_to_ctrack(h);
1527         help = nfct_help(ct);
1528
1529         if (!help || !help->helper) {
1530                 /* such conntrack hasn't got any helper, abort */
1531                 err = -EINVAL;
1532                 goto out;
1533         }
1534
1535         exp = nf_conntrack_expect_alloc(ct);
1536         if (!exp) {
1537                 err = -ENOMEM;
1538                 goto out;
1539         }
1540
1541         exp->expectfn = NULL;
1542         exp->flags = 0;
1543         exp->master = ct;
1544         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1545         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1546
1547         err = nf_conntrack_expect_related(exp);
1548         nf_conntrack_expect_put(exp);
1549
1550 out:
1551         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1552         return err;
1553 }
1554
1555 static int
1556 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1557                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1558 {
1559         struct nf_conntrack_tuple tuple;
1560         struct nf_conntrack_expect *exp;
1561         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1562         u_int8_t u3 = nfmsg->nfgen_family;
1563         int err = 0;
1564
1565         DEBUGP("entered %s\n", __FUNCTION__);
1566
1567         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1568                 return -EINVAL;
1569
1570         if (!cda[CTA_EXPECT_TUPLE-1]
1571             || !cda[CTA_EXPECT_MASK-1]
1572             || !cda[CTA_EXPECT_MASTER-1])
1573                 return -EINVAL;
1574
1575         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1576         if (err < 0)
1577                 return err;
1578
1579         write_lock_bh(&nf_conntrack_lock);
1580         exp = __nf_conntrack_expect_find(&tuple);
1581
1582         if (!exp) {
1583                 write_unlock_bh(&nf_conntrack_lock);
1584                 err = -ENOENT;
1585                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1586                         err = ctnetlink_create_expect(cda, u3);
1587                 return err;
1588         }
1589
1590         err = -EEXIST;
1591         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1592                 err = ctnetlink_change_expect(exp, cda);
1593         write_unlock_bh(&nf_conntrack_lock);
1594
1595         DEBUGP("leaving\n");
1596
1597         return err;
1598 }
1599
1600 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1601 static struct notifier_block ctnl_notifier = {
1602         .notifier_call  = ctnetlink_conntrack_event,
1603 };
1604
1605 static struct notifier_block ctnl_notifier_exp = {
1606         .notifier_call  = ctnetlink_expect_event,
1607 };
1608 #endif
1609
1610 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1611         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1612                                             .attr_count = CTA_MAX, },
1613         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1614                                             .attr_count = CTA_MAX, },
1615         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1616                                             .attr_count = CTA_MAX, },
1617         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1618                                             .attr_count = CTA_MAX, },
1619 };
1620
1621 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1622         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1623                                             .attr_count = CTA_EXPECT_MAX, },
1624         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1625                                             .attr_count = CTA_EXPECT_MAX, },
1626         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1627                                             .attr_count = CTA_EXPECT_MAX, },
1628 };
1629
1630 static struct nfnetlink_subsystem ctnl_subsys = {
1631         .name                           = "conntrack",
1632         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1633         .cb_count                       = IPCTNL_MSG_MAX,
1634         .cb                             = ctnl_cb,
1635 };
1636
1637 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1638         .name                           = "conntrack_expect",
1639         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1640         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1641         .cb                             = ctnl_exp_cb,
1642 };
1643
1644 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1645 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1646
1647 static int __init ctnetlink_init(void)
1648 {
1649         int ret;
1650
1651         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1652         ret = nfnetlink_subsys_register(&ctnl_subsys);
1653         if (ret < 0) {
1654                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1655                 goto err_out;
1656         }
1657
1658         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1659         if (ret < 0) {
1660                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1661                 goto err_unreg_subsys;
1662         }
1663
1664 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1665         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1666         if (ret < 0) {
1667                 printk("ctnetlink_init: cannot register notifier.\n");
1668                 goto err_unreg_exp_subsys;
1669         }
1670
1671         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1672         if (ret < 0) {
1673                 printk("ctnetlink_init: cannot expect register notifier.\n");
1674                 goto err_unreg_notifier;
1675         }
1676 #endif
1677
1678         return 0;
1679
1680 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1681 err_unreg_notifier:
1682         nf_conntrack_unregister_notifier(&ctnl_notifier);
1683 err_unreg_exp_subsys:
1684         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1685 #endif
1686 err_unreg_subsys:
1687         nfnetlink_subsys_unregister(&ctnl_subsys);
1688 err_out:
1689         return ret;
1690 }
1691
1692 static void __exit ctnetlink_exit(void)
1693 {
1694         printk("ctnetlink: unregistering from nfnetlink.\n");
1695
1696 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1697         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1698         nf_conntrack_unregister_notifier(&ctnl_notifier);
1699 #endif
1700
1701         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1702         nfnetlink_subsys_unregister(&ctnl_subsys);
1703         return;
1704 }
1705
1706 module_init(ctnetlink_init);
1707 module_exit(ctnetlink_exit);