net/netfilter/nf_conntrack_netlink.c

   1 /* Connection tracking via netlink socket. Allows for user space
   2  * protocol helpers and general trouble making from userspace.
   3  *
   4  * (C) 2001 by Jay Schulist <jschlst@samba.org>
   5  * (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
   6  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
   7  * (C) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net>
   8  *
   9  * I've reworked this stuff to use attributes instead of conntrack
  10  * structures. 5.44 am. I need more tea. --pablo 05/07/11.
  11  *
  12  * Initial connection tracking via netlink development funded and
  13  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
  14  *
  15  * Further development of this code funded by Astaro AG (http://www.astaro.com)
  16  *
  17  * This software may be used and distributed according to the terms
  18  * of the GNU General Public License, incorporated herein by reference.
  19  *
  20  * Derived from ip_conntrack_netlink.c: Port by Pablo Neira Ayuso (05/11/14)
  21  */
  22
  23 #include <linux/init.h>
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/types.h>
  27 #include <linux/timer.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/errno.h>
  30 #include <linux/netlink.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/interrupt.h>
  33 #include <linux/notifier.h>
  34
  35 #include <linux/netfilter.h>
  36 #include <net/netfilter/nf_conntrack.h>
  37 #include <net/netfilter/nf_conntrack_core.h>
  38 #include <net/netfilter/nf_conntrack_helper.h>
  39 #include <net/netfilter/nf_conntrack_l3proto.h>
  40 #include <net/netfilter/nf_conntrack_protocol.h>
  41 #include <linux/netfilter_ipv4/ip_nat_protocol.h>
  42
  43 #include <linux/netfilter/nfnetlink.h>
  44 #include <linux/netfilter/nfnetlink_conntrack.h>
  45
  46 MODULE_LICENSE("GPL");
  47
  48 static char __initdata version[] = "0.93";
  49
  50 #if 0
  51 #define DEBUGP printk
  52 #else
  53 #define DEBUGP(format, args...)
  54 #endif
  55
  56
  57 static inline int
  58 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  59                             const struct nf_conntrack_tuple *tuple,
  60                             struct nf_conntrack_protocol *proto)
  61 {
  62         int ret = 0;
  63         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
  64
  65         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
  66
  67         if (likely(proto->tuple_to_nfattr))
  68                 ret = proto->tuple_to_nfattr(skb, tuple);
  69
  70         NFA_NEST_END(skb, nest_parms);
  71
  72         return ret;
  73
  74 nfattr_failure:
  75         return -1;
  76 }
  77
  78 static inline int
  79 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  80                          const struct nf_conntrack_tuple *tuple,
  81                          struct nf_conntrack_l3proto *l3proto)
  82 {
  83         int ret = 0;
  84         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
  85
  86         if (likely(l3proto->tuple_to_nfattr))
  87                 ret = l3proto->tuple_to_nfattr(skb, tuple);
  88
  89         NFA_NEST_END(skb, nest_parms);
  90
  91         return ret;
  92
  93 nfattr_failure:
  94         return -1;
  95 }
  96
  97 static inline int
  98 ctnetlink_dump_tuples(struct sk_buff *skb,
  99                       const struct nf_conntrack_tuple *tuple)
 100 {
 101         int ret;
 102         struct nf_conntrack_l3proto *l3proto;
 103         struct nf_conntrack_protocol *proto;
 104
 105         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 106         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 107         nf_ct_l3proto_put(l3proto);
 108
 109         if (unlikely(ret < 0))
 110                 return ret;
 111
 112         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 113         ret = ctnetlink_dump_tuples_proto(skb, tuple, proto);
 114         nf_ct_proto_put(proto);
 115
 116         return ret;
 117 }
 118
 119 static inline int
 120 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 121 {
 122         u_int32_t status = htonl((u_int32_t) ct->status);
 123         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
 124         return 0;
 125
 126 nfattr_failure:
 127         return -1;
 128 }
 129
 130 static inline int
 131 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 132 {
 133         long timeout_l = ct->timeout.expires - jiffies;
 134         u_int32_t timeout;
 135
 136         if (timeout_l < 0)
 137                 timeout = 0;
 138         else
 139                 timeout = htonl(timeout_l / HZ);
 140
 141         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
 142         return 0;
 143
 144 nfattr_failure:
 145         return -1;
 146 }
 147
 148 static inline int
 149 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
 150 {
 151         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);
 152         struct nfattr *nest_proto;
 153         int ret;
 154
 155         if (!proto->to_nfattr) {
 156                 nf_ct_proto_put(proto);
 157                 return 0;
 158         }
 159
 160         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
 161
 162         ret = proto->to_nfattr(skb, nest_proto, ct);
 163
 164         nf_ct_proto_put(proto);
 165
 166         NFA_NEST_END(skb, nest_proto);
 167
 168         return ret;
 169
 170 nfattr_failure:
 171         return -1;
 172 }
 173
 174 static inline int
 175 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 176 {
 177         struct nfattr *nest_helper;
 178         const struct nf_conn_help *help = nfct_help(ct);
 179
 180         if (!help || !help->helper)
 181                 return 0;
 182
 183         nest_helper = NFA_NEST(skb, CTA_HELP);
 184         NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
 185
 186         if (help->helper->to_nfattr)
 187                 help->helper->to_nfattr(skb, ct);
 188
 189         NFA_NEST_END(skb, nest_helper);
 190
 191         return 0;
 192
 193 nfattr_failure:
 194         return -1;
 195 }
 196
 197 #ifdef CONFIG_NF_CT_ACCT
 198 static inline int
 199 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 200                         enum ip_conntrack_dir dir)
 201 {
 202         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 203         struct nfattr *nest_count = NFA_NEST(skb, type);
 204         u_int32_t tmp;
 205
 206         tmp = htonl(ct->counters[dir].packets);
 207         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
 208
 209         tmp = htonl(ct->counters[dir].bytes);
 210         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
 211
 212         NFA_NEST_END(skb, nest_count);
 213
 214         return 0;
 215
 216 nfattr_failure:
 217         return -1;
 218 }
 219 #else
 220 #define ctnetlink_dump_counters(a, b, c) (0)
 221 #endif
 222
 223 #ifdef CONFIG_NF_CONNTRACK_MARK
 224 static inline int
 225 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 226 {
 227         u_int32_t mark = htonl(ct->mark);
 228
 229         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
 230         return 0;
 231
 232 nfattr_failure:
 233         return -1;
 234 }
 235 #else
 236 #define ctnetlink_dump_mark(a, b) (0)
 237 #endif
 238
 239 static inline int
 240 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 241 {
 242         u_int32_t id = htonl(ct->id);
 243         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
 244         return 0;
 245
 246 nfattr_failure:
 247         return -1;
 248 }
 249
 250 static inline int
 251 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 252 {
 253         u_int32_t use = htonl(atomic_read(&ct->ct_general.use));
 254
 255         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
 256         return 0;
 257
 258 nfattr_failure:
 259         return -1;
 260 }
 261
 262 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
 263
 264 static int
 265 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
 266                     int event, int nowait,
 267                     const struct nf_conn *ct)
 268 {
 269         struct nlmsghdr *nlh;
 270         struct nfgenmsg *nfmsg;
 271         struct nfattr *nest_parms;
 272         unsigned char *b;
 273
 274         b = skb->tail;
 275
 276         event |= NFNL_SUBSYS_CTNETLINK << 8;
 277         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
 278         nfmsg  = NLMSG_DATA(nlh);
 279
 280         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
 281         nfmsg->nfgen_family =
 282                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 283         nfmsg->version      = NFNETLINK_V0;
 284         nfmsg->res_id       = 0;
 285
 286         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 287         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 288                 goto nfattr_failure;
 289         NFA_NEST_END(skb, nest_parms);
 290
 291         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 292         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 293                 goto nfattr_failure;
 294         NFA_NEST_END(skb, nest_parms);
 295
 296         if (ctnetlink_dump_status(skb, ct) < 0 ||
 297             ctnetlink_dump_timeout(skb, ct) < 0 ||
 298             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 299             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
 300             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 301             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 302             ctnetlink_dump_mark(skb, ct) < 0 ||
 303             ctnetlink_dump_id(skb, ct) < 0 ||
 304             ctnetlink_dump_use(skb, ct) < 0)
 305                 goto nfattr_failure;
 306
 307         nlh->nlmsg_len = skb->tail - b;
 308         return skb->len;
 309
 310 nlmsg_failure:
 311 nfattr_failure:
 312         skb_trim(skb, b - skb->data);
 313         return -1;
 314 }
 315
 316 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 317 static int ctnetlink_conntrack_event(struct notifier_block *this,
 318                                      unsigned long events, void *ptr)
 319 {
 320         struct nlmsghdr *nlh;
 321         struct nfgenmsg *nfmsg;
 322         struct nfattr *nest_parms;
 323         struct nf_conn *ct = (struct nf_conn *)ptr;
 324         struct sk_buff *skb;
 325         unsigned int type;
 326         unsigned char *b;
 327         unsigned int flags = 0, group;
 328
 329         /* ignore our fake conntrack entry */
 330         if (ct == &nf_conntrack_untracked)
 331                 return NOTIFY_DONE;
 332
 333         if (events & IPCT_DESTROY) {
 334                 type = IPCTNL_MSG_CT_DELETE;
 335                 group = NFNLGRP_CONNTRACK_DESTROY;
 336         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
 337                 type = IPCTNL_MSG_CT_NEW;
 338                 flags = NLM_F_CREATE|NLM_F_EXCL;
 339                 /* dump everything */
 340                 events = ~0UL;
 341                 group = NFNLGRP_CONNTRACK_NEW;
 342         } else  if (events & (IPCT_STATUS |
 343                       IPCT_PROTOINFO |
 344                       IPCT_HELPER |
 345                       IPCT_HELPINFO |
 346                       IPCT_NATINFO)) {
 347                 type = IPCTNL_MSG_CT_NEW;
 348                 group = NFNLGRP_CONNTRACK_UPDATE;
 349         } else
 350                 return NOTIFY_DONE;
 351
 352         if (!nfnetlink_has_listeners(group))
 353                 return NOTIFY_DONE;
 354
 355         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 356         if (!skb)
 357                 return NOTIFY_DONE;
 358
 359         b = skb->tail;
 360
 361         type |= NFNL_SUBSYS_CTNETLINK << 8;
 362         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
 363         nfmsg = NLMSG_DATA(nlh);
 364
 365         nlh->nlmsg_flags    = flags;
 366         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 367         nfmsg->version  = NFNETLINK_V0;
 368         nfmsg->res_id   = 0;
 369
 370         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
 371         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 372                 goto nfattr_failure;
 373         NFA_NEST_END(skb, nest_parms);
 374
 375         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
 376         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
 377                 goto nfattr_failure;
 378         NFA_NEST_END(skb, nest_parms);
 379
 380         /* NAT stuff is now a status flag */
 381         if ((events & IPCT_STATUS || events & IPCT_NATINFO)
 382             && ctnetlink_dump_status(skb, ct) < 0)
 383                 goto nfattr_failure;
 384         if (events & IPCT_REFRESH
 385             && ctnetlink_dump_timeout(skb, ct) < 0)
 386                 goto nfattr_failure;
 387         if (events & IPCT_PROTOINFO
 388             && ctnetlink_dump_protoinfo(skb, ct) < 0)
 389                 goto nfattr_failure;
 390         if (events & IPCT_HELPINFO
 391             && ctnetlink_dump_helpinfo(skb, ct) < 0)
 392                 goto nfattr_failure;
 393
 394         if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
 395             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
 396                 goto nfattr_failure;
 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         DEBUGP("entered %s\n", __FUNCTION__);
 414         return 0;
 415 }
 416
 417 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 418
 419 static int
 420 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 421 {
 422         struct nf_conn *ct, *last;
 423         struct nf_conntrack_tuple_hash *h;
 424         struct list_head *i;
 425         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 426         u_int8_t l3proto = nfmsg->nfgen_family;
 427
 428         DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__,
 429                         cb->args[0], *id);
 430
 431         read_lock_bh(&nf_conntrack_lock);
 432         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
 433 restart:
 434                 last = (struct nf_conn *)cb->args[1];
 435                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 436                         h = (struct nf_conntrack_tuple_hash *) i;
 437                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 438                                 continue;
 439                         ct = nf_ct_tuplehash_to_ctrack(h);
 440                         /* Dump entries of a given L3 protocol number.
 441                          * If it is not specified, ie. l3proto == 0,
 442                          * then dump everything. */
 443                         if (l3proto && L3PROTO(ct) != l3proto)
 444                                 continue;
 445                         if (last != NULL) {
 446                                 if (ct == last) {
 447                                         nf_ct_put(last);
 448                                         cb->args[1] = 0;
 449                                         last = NULL;
 450                                 } else
 451                                         continue;
 452                         }
 453                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 454                                                 cb->nlh->nlmsg_seq,
 455                                                 IPCTNL_MSG_CT_NEW,
 456                                                 1, ct) < 0) {
 457                                 nf_conntrack_get(&ct->ct_general);
 458                                 cb->args[1] = (unsigned long)ct;
 459                                 goto out;
 460                         }
 461                 }
 462                 if (last != NULL) {
 463                         nf_ct_put(last);
 464                         cb->args[1] = 0;
 465                         goto restart;
 466                 }
 467         }
 468 out:
 469         read_unlock_bh(&nf_conntrack_lock);
 470
 471         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 472
 473         return skb->len;
 474 }
 475
 476 #ifdef CONFIG_NF_CT_ACCT
 477 static int
 478 ctnetlink_dump_table_w(struct sk_buff *skb, struct netlink_callback *cb)
 479 {
 480         struct nf_conn *ct = NULL;
 481         struct nf_conntrack_tuple_hash *h;
 482         struct list_head *i;
 483         u_int32_t *id = (u_int32_t *) &cb->args[1];
 484         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 485         u_int8_t l3proto = nfmsg->nfgen_family;
 486
 487         DEBUGP("entered %s, last bucket=%u id=%u\n", __FUNCTION__,
 488                         cb->args[0], *id);
 489
 490         write_lock_bh(&nf_conntrack_lock);
 491         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 492                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 493                         h = (struct nf_conntrack_tuple_hash *) i;
 494                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 495                                 continue;
 496                         ct = nf_ct_tuplehash_to_ctrack(h);
 497                         if (l3proto && L3PROTO(ct) != l3proto)
 498                                 continue;
 499                         if (ct->id <= *id)
 500                                 continue;
 501                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 502                                                 cb->nlh->nlmsg_seq,
 503                                                 IPCTNL_MSG_CT_NEW,
 504                                                 1, ct) < 0)
 505                                 goto out;
 506                         *id = ct->id;
 507
 508                         memset(&ct->counters, 0, sizeof(ct->counters));
 509                 }
 510         }
 511 out:
 512         write_unlock_bh(&nf_conntrack_lock);
 513
 514         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 515
 516         return skb->len;
 517 }
 518 #endif
 519
 520 static inline int
 521 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 522 {
 523         struct nfattr *tb[CTA_IP_MAX];
 524         struct nf_conntrack_l3proto *l3proto;
 525         int ret = 0;
 526
 527         DEBUGP("entered %s\n", __FUNCTION__);
 528
 529         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 530
 531         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 532
 533         if (likely(l3proto->nfattr_to_tuple))
 534                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 535
 536         nf_ct_l3proto_put(l3proto);
 537
 538         DEBUGP("leaving\n");
 539
 540         return ret;
 541 }
 542
 543 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 544         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 545 };
 546
 547 static inline int
 548 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 549                             struct nf_conntrack_tuple *tuple)
 550 {
 551         struct nfattr *tb[CTA_PROTO_MAX];
 552         struct nf_conntrack_protocol *proto;
 553         int ret = 0;
 554
 555         DEBUGP("entered %s\n", __FUNCTION__);
 556
 557         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 558
 559         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 560                 return -EINVAL;
 561
 562         if (!tb[CTA_PROTO_NUM-1])
 563                 return -EINVAL;
 564         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 565
 566         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 567
 568         if (likely(proto->nfattr_to_tuple))
 569                 ret = proto->nfattr_to_tuple(tb, tuple);
 570
 571         nf_ct_proto_put(proto);
 572
 573         return ret;
 574 }
 575
 576 static inline int
 577 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 578                       enum ctattr_tuple type, u_int8_t l3num)
 579 {
 580         struct nfattr *tb[CTA_TUPLE_MAX];
 581         int err;
 582
 583         DEBUGP("entered %s\n", __FUNCTION__);
 584
 585         memset(tuple, 0, sizeof(*tuple));
 586
 587         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 588
 589         if (!tb[CTA_TUPLE_IP-1])
 590                 return -EINVAL;
 591
 592         tuple->src.l3num = l3num;
 593
 594         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 595         if (err < 0)
 596                 return err;
 597
 598         if (!tb[CTA_TUPLE_PROTO-1])
 599                 return -EINVAL;
 600
 601         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 602         if (err < 0)
 603                 return err;
 604
 605         /* orig and expect tuples get DIR_ORIGINAL */
 606         if (type == CTA_TUPLE_REPLY)
 607                 tuple->dst.dir = IP_CT_DIR_REPLY;
 608         else
 609                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 610
 611         NF_CT_DUMP_TUPLE(tuple);
 612
 613         DEBUGP("leaving\n");
 614
 615         return 0;
 616 }
 617
 618 #ifdef CONFIG_IP_NF_NAT_NEEDED
 619 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 620         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 621         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 622 };
 623
 624 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 625                                      const struct nf_conn *ct,
 626                                      struct ip_nat_range *range)
 627 {
 628         struct nfattr *tb[CTA_PROTONAT_MAX];
 629         struct ip_nat_protocol *npt;
 630
 631         DEBUGP("entered %s\n", __FUNCTION__);
 632
 633         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 634
 635         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 636                 return -EINVAL;
 637
 638         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 639
 640         if (!npt->nfattr_to_range) {
 641                 ip_nat_proto_put(npt);
 642                 return 0;
 643         }
 644
 645         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 646         if (npt->nfattr_to_range(tb, range) > 0)
 647                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 648
 649         ip_nat_proto_put(npt);
 650
 651         DEBUGP("leaving\n");
 652         return 0;
 653 }
 654
 655 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 656         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 657         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 658 };
 659
 660 static inline int
 661 ctnetlink_parse_nat(struct nfattr *nat,
 662                     const struct nf_conn *ct, struct ip_nat_range *range)
 663 {
 664         struct nfattr *tb[CTA_NAT_MAX];
 665         int err;
 666
 667         DEBUGP("entered %s\n", __FUNCTION__);
 668
 669         memset(range, 0, sizeof(*range));
 670
 671         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
 672
 673         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 674                 return -EINVAL;
 675
 676         if (tb[CTA_NAT_MINIP-1])
 677                 range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 678
 679         if (!tb[CTA_NAT_MAXIP-1])
 680                 range->max_ip = range->min_ip;
 681         else
 682                 range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 683
 684         if (range->min_ip)
 685                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 686
 687         if (!tb[CTA_NAT_PROTO-1])
 688                 return 0;
 689
 690         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 691         if (err < 0)
 692                 return err;
 693
 694         DEBUGP("leaving\n");
 695         return 0;
 696 }
 697 #endif
 698
 699 static inline int
 700 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 701 {
 702         struct nfattr *tb[CTA_HELP_MAX];
 703
 704         DEBUGP("entered %s\n", __FUNCTION__);
 705
 706         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 707
 708         if (!tb[CTA_HELP_NAME-1])
 709                 return -EINVAL;
 710
 711         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 712
 713         return 0;
 714 }
 715
 716 static const size_t cta_min[CTA_MAX] = {
 717         [CTA_STATUS-1]          = sizeof(u_int32_t),
 718         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 719         [CTA_MARK-1]            = sizeof(u_int32_t),
 720         [CTA_USE-1]             = sizeof(u_int32_t),
 721         [CTA_ID-1]              = sizeof(u_int32_t)
 722 };
 723
 724 static int
 725 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 726                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 727 {
 728         struct nf_conntrack_tuple_hash *h;
 729         struct nf_conntrack_tuple tuple;
 730         struct nf_conn *ct;
 731         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 732         u_int8_t u3 = nfmsg->nfgen_family;
 733         int err = 0;
 734
 735         DEBUGP("entered %s\n", __FUNCTION__);
 736
 737         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 738                 return -EINVAL;
 739
 740         if (cda[CTA_TUPLE_ORIG-1])
 741                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 742         else if (cda[CTA_TUPLE_REPLY-1])
 743                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 744         else {
 745                 /* Flush the whole table */
 746                 nf_conntrack_flush();
 747                 return 0;
 748         }
 749
 750         if (err < 0)
 751                 return err;
 752
 753         h = nf_conntrack_find_get(&tuple, NULL);
 754         if (!h) {
 755                 DEBUGP("tuple not found in conntrack hash\n");
 756                 return -ENOENT;
 757         }
 758
 759         ct = nf_ct_tuplehash_to_ctrack(h);
 760
 761         if (cda[CTA_ID-1]) {
 762                 u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1]));
 763                 if (ct->id != id) {
 764                         nf_ct_put(ct);
 765                         return -ENOENT;
 766                 }
 767         }
 768         if (del_timer(&ct->timeout))
 769                 ct->timeout.function((unsigned long)ct);
 770
 771         nf_ct_put(ct);
 772         DEBUGP("leaving\n");
 773
 774         return 0;
 775 }
 776
 777 static int
 778 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 779                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 780 {
 781         struct nf_conntrack_tuple_hash *h;
 782         struct nf_conntrack_tuple tuple;
 783         struct nf_conn *ct;
 784         struct sk_buff *skb2 = NULL;
 785         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 786         u_int8_t u3 = nfmsg->nfgen_family;
 787         int err = 0;
 788
 789         DEBUGP("entered %s\n", __FUNCTION__);
 790
 791         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 792                 u32 rlen;
 793
 794                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) ==
 795                                         IPCTNL_MSG_CT_GET_CTRZERO) {
 796 #ifdef CONFIG_NF_CT_ACCT
 797                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 798                                                 ctnetlink_dump_table_w,
 799                                                 ctnetlink_done)) != 0)
 800                                 return -EINVAL;
 801 #else
 802                         return -ENOTSUPP;
 803 #endif
 804                 } else {
 805                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 806                                                         ctnetlink_dump_table,
 807                                                         ctnetlink_done)) != 0)
 808                         return -EINVAL;
 809                 }
 810
 811                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 812                 if (rlen > skb->len)
 813                         rlen = skb->len;
 814                 skb_pull(skb, rlen);
 815                 return 0;
 816         }
 817
 818         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 819                 return -EINVAL;
 820
 821         if (cda[CTA_TUPLE_ORIG-1])
 822                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 823         else if (cda[CTA_TUPLE_REPLY-1])
 824                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 825         else
 826                 return -EINVAL;
 827
 828         if (err < 0)
 829                 return err;
 830
 831         h = nf_conntrack_find_get(&tuple, NULL);
 832         if (!h) {
 833                 DEBUGP("tuple not found in conntrack hash");
 834                 return -ENOENT;
 835         }
 836         DEBUGP("tuple found\n");
 837         ct = nf_ct_tuplehash_to_ctrack(h);
 838
 839         err = -ENOMEM;
 840         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 841         if (!skb2) {
 842                 nf_ct_put(ct);
 843                 return -ENOMEM;
 844         }
 845         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
 846
 847         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 848                                   IPCTNL_MSG_CT_NEW, 1, ct);
 849         nf_ct_put(ct);
 850         if (err <= 0)
 851                 goto free;
 852
 853         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 854         if (err < 0)
 855                 goto out;
 856
 857         DEBUGP("leaving\n");
 858         return 0;
 859
 860 free:
 861         kfree_skb(skb2);
 862 out:
 863         return err;
 864 }
 865
 866 static inline int
 867 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 868 {
 869         unsigned long d;
 870         unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1]));
 871         d = ct->status ^ status;
 872
 873         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 874                 /* unchangeable */
 875                 return -EINVAL;
 876
 877         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 878                 /* SEEN_REPLY bit can only be set */
 879                 return -EINVAL;
 880
 881
 882         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 883                 /* ASSURED bit can only be set */
 884                 return -EINVAL;
 885
 886         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
 887 #ifndef CONFIG_IP_NF_NAT_NEEDED
 888                 return -EINVAL;
 889 #else
 890                 struct ip_nat_range range;
 891
 892                 if (cda[CTA_NAT_DST-1]) {
 893                         if (ctnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
 894                                                 &range) < 0)
 895                                 return -EINVAL;
 896                         if (ip_nat_initialized(ct,
 897                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
 898                                 return -EEXIST;
 899                         ip_nat_setup_info(ct, &range, hooknum);
 900                 }
 901                 if (cda[CTA_NAT_SRC-1]) {
 902                         if (ctnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
 903                                                 &range) < 0)
 904                                 return -EINVAL;
 905                         if (ip_nat_initialized(ct,
 906                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
 907                                 return -EEXIST;
 908                         ip_nat_setup_info(ct, &range, hooknum);
 909                 }
 910 #endif
 911         }
 912
 913         /* Be careful here, modifying NAT bits can screw up things,
 914          * so don't let users modify them directly if they don't pass
 915          * ip_nat_range. */
 916         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 917         return 0;
 918 }
 919
 920
 921 static inline int
 922 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 923 {
 924         struct nf_conntrack_helper *helper;
 925         struct nf_conn_help *help = nfct_help(ct);
 926         char *helpname;
 927         int err;
 928
 929         DEBUGP("entered %s\n", __FUNCTION__);
 930
 931         if (!help) {
 932                 /* FIXME: we need to reallocate and rehash */
 933                 return -EBUSY;
 934         }
 935
 936         /* don't change helper of sibling connections */
 937         if (ct->master)
 938                 return -EINVAL;
 939
 940         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 941         if (err < 0)
 942                 return err;
 943
 944         helper = __nf_conntrack_helper_find_byname(helpname);
 945         if (!helper) {
 946                 if (!strcmp(helpname, ""))
 947                         helper = NULL;
 948                 else
 949                         return -EINVAL;
 950         }
 951
 952         if (help->helper) {
 953                 if (!helper) {
 954                         /* we had a helper before ... */
 955                         nf_ct_remove_expectations(ct);
 956                         help->helper = NULL;
 957                 } else {
 958                         /* need to zero data of old helper */
 959                         memset(&help->help, 0, sizeof(help->help));
 960                 }
 961         }
 962
 963         help->helper = helper;
 964
 965         return 0;
 966 }
 967
 968 static inline int
 969 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 970 {
 971         u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 972
 973         if (!del_timer(&ct->timeout))
 974                 return -ETIME;
 975
 976         ct->timeout.expires = jiffies + timeout * HZ;
 977         add_timer(&ct->timeout);
 978
 979         return 0;
 980 }
 981
 982 static inline int
 983 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 984 {
 985         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 986         struct nf_conntrack_protocol *proto;
 987         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 988         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 989         int err = 0;
 990
 991         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 992
 993         proto = nf_ct_proto_find_get(l3num, npt);
 994
 995         if (proto->from_nfattr)
 996                 err = proto->from_nfattr(tb, ct);
 997         nf_ct_proto_put(proto);
 998
 999         return err;
1000 }
1001
1002 static int
1003 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
1004 {
1005         int err;
1006
1007         DEBUGP("entered %s\n", __FUNCTION__);
1008
1009         if (cda[CTA_HELP-1]) {
1010                 err = ctnetlink_change_helper(ct, cda);
1011                 if (err < 0)
1012                         return err;
1013         }
1014
1015         if (cda[CTA_TIMEOUT-1]) {
1016                 err = ctnetlink_change_timeout(ct, cda);
1017                 if (err < 0)
1018                         return err;
1019         }
1020
1021         if (cda[CTA_STATUS-1]) {
1022                 err = ctnetlink_change_status(ct, cda);
1023                 if (err < 0)
1024                         return err;
1025         }
1026
1027         if (cda[CTA_PROTOINFO-1]) {
1028                 err = ctnetlink_change_protoinfo(ct, cda);
1029                 if (err < 0)
1030                         return err;
1031         }
1032
1033 #if defined(CONFIG_NF_CONNTRACK_MARK)
1034         if (cda[CTA_MARK-1])
1035                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1036 #endif
1037
1038         DEBUGP("all done\n");
1039         return 0;
1040 }
1041
1042 static int
1043 ctnetlink_create_conntrack(struct nfattr *cda[],
1044                            struct nf_conntrack_tuple *otuple,
1045                            struct nf_conntrack_tuple *rtuple)
1046 {
1047         struct nf_conn *ct;
1048         int err = -EINVAL;
1049
1050         DEBUGP("entered %s\n", __FUNCTION__);
1051
1052         ct = nf_conntrack_alloc(otuple, rtuple);
1053         if (ct == NULL || IS_ERR(ct))
1054                 return -ENOMEM;
1055
1056         if (!cda[CTA_TIMEOUT-1])
1057                 goto err;
1058         ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
1059
1060         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1061         ct->status |= IPS_CONFIRMED;
1062
1063         err = ctnetlink_change_status(ct, cda);
1064         if (err < 0)
1065                 goto err;
1066
1067         if (cda[CTA_PROTOINFO-1]) {
1068                 err = ctnetlink_change_protoinfo(ct, cda);
1069                 if (err < 0)
1070                         return err;
1071         }
1072
1073 #if defined(CONFIG_NF_CONNTRACK_MARK)
1074         if (cda[CTA_MARK-1])
1075                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1076 #endif
1077
1078         add_timer(&ct->timeout);
1079         nf_conntrack_hash_insert(ct);
1080
1081         DEBUGP("conntrack with id %u inserted\n", ct->id);
1082         return 0;
1083
1084 err:
1085         nf_conntrack_free(ct);
1086         return err;
1087 }
1088
1089 static int
1090 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1091                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1092 {
1093         struct nf_conntrack_tuple otuple, rtuple;
1094         struct nf_conntrack_tuple_hash *h = NULL;
1095         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1096         u_int8_t u3 = nfmsg->nfgen_family;
1097         int err = 0;
1098
1099         DEBUGP("entered %s\n", __FUNCTION__);
1100
1101         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1102                 return -EINVAL;
1103
1104         if (cda[CTA_TUPLE_ORIG-1]) {
1105                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1106                 if (err < 0)
1107                         return err;
1108         }
1109
1110         if (cda[CTA_TUPLE_REPLY-1]) {
1111                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1112                 if (err < 0)
1113                         return err;
1114         }
1115
1116         write_lock_bh(&nf_conntrack_lock);
1117         if (cda[CTA_TUPLE_ORIG-1])
1118                 h = __nf_conntrack_find(&otuple, NULL);
1119         else if (cda[CTA_TUPLE_REPLY-1])
1120                 h = __nf_conntrack_find(&rtuple, NULL);
1121
1122         if (h == NULL) {
1123                 write_unlock_bh(&nf_conntrack_lock);
1124                 DEBUGP("no such conntrack, create new\n");
1125                 err = -ENOENT;
1126                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1127                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1128                 return err;
1129         }
1130         /* implicit 'else' */
1131
1132         /* we only allow nat config for new conntracks */
1133         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1134                 err = -EINVAL;
1135                 goto out_unlock;
1136         }
1137
1138         /* We manipulate the conntrack inside the global conntrack table lock,
1139          * so there's no need to increase the refcount */
1140         DEBUGP("conntrack found\n");
1141         err = -EEXIST;
1142         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1143                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1144
1145 out_unlock:
1146         write_unlock_bh(&nf_conntrack_lock);
1147         return err;
1148 }
1149
1150 /***********************************************************************
1151  * EXPECT
1152  ***********************************************************************/
1153
1154 static inline int
1155 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1156                          const struct nf_conntrack_tuple *tuple,
1157                          enum ctattr_expect type)
1158 {
1159         struct nfattr *nest_parms = NFA_NEST(skb, type);
1160
1161         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1162                 goto nfattr_failure;
1163
1164         NFA_NEST_END(skb, nest_parms);
1165
1166         return 0;
1167
1168 nfattr_failure:
1169         return -1;
1170 }
1171
1172 static inline int
1173 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1174                         const struct nf_conntrack_tuple *tuple,
1175                         const struct nf_conntrack_tuple *mask)
1176 {
1177         int ret;
1178         struct nf_conntrack_l3proto *l3proto;
1179         struct nf_conntrack_protocol *proto;
1180         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1181
1182         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1183         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1184         nf_ct_l3proto_put(l3proto);
1185
1186         if (unlikely(ret < 0))
1187                 goto nfattr_failure;
1188
1189         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1190         ret = ctnetlink_dump_tuples_proto(skb, mask, proto);
1191         nf_ct_proto_put(proto);
1192         if (unlikely(ret < 0))
1193                 goto nfattr_failure;
1194
1195         NFA_NEST_END(skb, nest_parms);
1196
1197         return 0;
1198
1199 nfattr_failure:
1200         return -1;
1201 }
1202
1203 static inline int
1204 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1205                           const struct nf_conntrack_expect *exp)
1206 {
1207         struct nf_conn *master = exp->master;
1208         u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1209         u_int32_t id = htonl(exp->id);
1210
1211         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1212                 goto nfattr_failure;
1213         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1214                 goto nfattr_failure;
1215         if (ctnetlink_exp_dump_tuple(skb,
1216                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1217                                  CTA_EXPECT_MASTER) < 0)
1218                 goto nfattr_failure;
1219
1220         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1221         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1222
1223         return 0;
1224
1225 nfattr_failure:
1226         return -1;
1227 }
1228
1229 static int
1230 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1231                     int event,
1232                     int nowait,
1233                     const struct nf_conntrack_expect *exp)
1234 {
1235         struct nlmsghdr *nlh;
1236         struct nfgenmsg *nfmsg;
1237         unsigned char *b;
1238
1239         b = skb->tail;
1240
1241         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1242         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1243         nfmsg  = NLMSG_DATA(nlh);
1244
1245         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1246         nfmsg->nfgen_family = exp->tuple.src.l3num;
1247         nfmsg->version      = NFNETLINK_V0;
1248         nfmsg->res_id       = 0;
1249
1250         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1251                 goto nfattr_failure;
1252
1253         nlh->nlmsg_len = skb->tail - b;
1254         return skb->len;
1255
1256 nlmsg_failure:
1257 nfattr_failure:
1258         skb_trim(skb, b - skb->data);
1259         return -1;
1260 }
1261
1262 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1263 static int ctnetlink_expect_event(struct notifier_block *this,
1264                                   unsigned long events, void *ptr)
1265 {
1266         struct nlmsghdr *nlh;
1267         struct nfgenmsg *nfmsg;
1268         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1269         struct sk_buff *skb;
1270         unsigned int type;
1271         unsigned char *b;
1272         int flags = 0;
1273
1274         if (events & IPEXP_NEW) {
1275                 type = IPCTNL_MSG_EXP_NEW;
1276                 flags = NLM_F_CREATE|NLM_F_EXCL;
1277         } else
1278                 return NOTIFY_DONE;
1279
1280         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1281         if (!skb)
1282                 return NOTIFY_DONE;
1283
1284         b = skb->tail;
1285
1286         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1287         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1288         nfmsg = NLMSG_DATA(nlh);
1289
1290         nlh->nlmsg_flags    = flags;
1291         nfmsg->nfgen_family = exp->tuple.src.l3num;
1292         nfmsg->version      = NFNETLINK_V0;
1293         nfmsg->res_id       = 0;
1294
1295         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1296                 goto nfattr_failure;
1297
1298         nlh->nlmsg_len = skb->tail - b;
1299         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1300         return NOTIFY_DONE;
1301
1302 nlmsg_failure:
1303 nfattr_failure:
1304         kfree_skb(skb);
1305         return NOTIFY_DONE;
1306 }
1307 #endif
1308
1309 static int
1310 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1311 {
1312         struct nf_conntrack_expect *exp = NULL;
1313         struct list_head *i;
1314         u_int32_t *id = (u_int32_t *) &cb->args[0];
1315         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1316         u_int8_t l3proto = nfmsg->nfgen_family;
1317
1318         DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id);
1319
1320         read_lock_bh(&nf_conntrack_lock);
1321         list_for_each_prev(i, &nf_conntrack_expect_list) {
1322                 exp = (struct nf_conntrack_expect *) i;
1323                 if (l3proto && exp->tuple.src.l3num != l3proto)
1324                         continue;
1325                 if (exp->id <= *id)
1326                         continue;
1327                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1328                                             cb->nlh->nlmsg_seq,
1329                                             IPCTNL_MSG_EXP_NEW,
1330                                             1, exp) < 0)
1331                         goto out;
1332                 *id = exp->id;
1333         }
1334 out:
1335         read_unlock_bh(&nf_conntrack_lock);
1336
1337         DEBUGP("leaving, last id=%llu\n", *id);
1338
1339         return skb->len;
1340 }
1341
1342 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1343         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1344         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1345 };
1346
1347 static int
1348 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1349                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1350 {
1351         struct nf_conntrack_tuple tuple;
1352         struct nf_conntrack_expect *exp;
1353         struct sk_buff *skb2;
1354         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1355         u_int8_t u3 = nfmsg->nfgen_family;
1356         int err = 0;
1357
1358         DEBUGP("entered %s\n", __FUNCTION__);
1359
1360         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1361                 return -EINVAL;
1362
1363         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1364                 u32 rlen;
1365
1366                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1367                                                 ctnetlink_exp_dump_table,
1368                                                 ctnetlink_done)) != 0)
1369                         return -EINVAL;
1370                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1371                 if (rlen > skb->len)
1372                         rlen = skb->len;
1373                 skb_pull(skb, rlen);
1374                 return 0;
1375         }
1376
1377         if (cda[CTA_EXPECT_MASTER-1])
1378                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1379         else
1380                 return -EINVAL;
1381
1382         if (err < 0)
1383                 return err;
1384
1385         exp = nf_conntrack_expect_find(&tuple);
1386         if (!exp)
1387                 return -ENOENT;
1388
1389         if (cda[CTA_EXPECT_ID-1]) {
1390                 u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1391                 if (exp->id != ntohl(id)) {
1392                         nf_conntrack_expect_put(exp);
1393                         return -ENOENT;
1394                 }
1395         }
1396
1397         err = -ENOMEM;
1398         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1399         if (!skb2)
1400                 goto out;
1401         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
1402
1403         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1404                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1405                                       1, exp);
1406         if (err <= 0)
1407                 goto free;
1408
1409         nf_conntrack_expect_put(exp);
1410
1411         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1412
1413 free:
1414         kfree_skb(skb2);
1415 out:
1416         nf_conntrack_expect_put(exp);
1417         return err;
1418 }
1419
1420 static int
1421 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1422                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1423 {
1424         struct nf_conntrack_expect *exp, *tmp;
1425         struct nf_conntrack_tuple tuple;
1426         struct nf_conntrack_helper *h;
1427         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1428         u_int8_t u3 = nfmsg->nfgen_family;
1429         int err;
1430
1431         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1432                 return -EINVAL;
1433
1434         if (cda[CTA_EXPECT_TUPLE-1]) {
1435                 /* delete a single expect by tuple */
1436                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1437                 if (err < 0)
1438                         return err;
1439
1440                 /* bump usage count to 2 */
1441                 exp = nf_conntrack_expect_find(&tuple);
1442                 if (!exp)
1443                         return -ENOENT;
1444
1445                 if (cda[CTA_EXPECT_ID-1]) {
1446                         u_int32_t id =
1447                                 *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1448                         if (exp->id != ntohl(id)) {
1449                                 nf_conntrack_expect_put(exp);
1450                                 return -ENOENT;
1451                         }
1452                 }
1453
1454                 /* after list removal, usage count == 1 */
1455                 nf_conntrack_unexpect_related(exp);
1456                 /* have to put what we 'get' above.
1457                  * after this line usage count == 0 */
1458                 nf_conntrack_expect_put(exp);
1459         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1460                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1461
1462                 /* delete all expectations for this helper */
1463                 write_lock_bh(&nf_conntrack_lock);
1464                 h = __nf_conntrack_helper_find_byname(name);
1465                 if (!h) {
1466                         write_unlock_bh(&nf_conntrack_lock);
1467                         return -EINVAL;
1468                 }
1469                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1470                                          list) {
1471                         struct nf_conn_help *m_help = nfct_help(exp->master);
1472                         if (m_help->helper == h
1473                             && del_timer(&exp->timeout)) {
1474                                 nf_ct_unlink_expect(exp);
1475                                 nf_conntrack_expect_put(exp);
1476                         }
1477                 }
1478                 write_unlock_bh(&nf_conntrack_lock);
1479         } else {
1480                 /* This basically means we have to flush everything*/
1481                 write_lock_bh(&nf_conntrack_lock);
1482                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1483                                          list) {
1484                         if (del_timer(&exp->timeout)) {
1485                                 nf_ct_unlink_expect(exp);
1486                                 nf_conntrack_expect_put(exp);
1487                         }
1488                 }
1489                 write_unlock_bh(&nf_conntrack_lock);
1490         }
1491
1492         return 0;
1493 }
1494 static int
1495 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1496 {
1497         return -EOPNOTSUPP;
1498 }
1499
1500 static int
1501 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1502 {
1503         struct nf_conntrack_tuple tuple, mask, master_tuple;
1504         struct nf_conntrack_tuple_hash *h = NULL;
1505         struct nf_conntrack_expect *exp;
1506         struct nf_conn *ct;
1507         struct nf_conn_help *help;
1508         int err = 0;
1509
1510         DEBUGP("entered %s\n", __FUNCTION__);
1511
1512         /* caller guarantees that those three CTA_EXPECT_* exist */
1513         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1514         if (err < 0)
1515                 return err;
1516         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1517         if (err < 0)
1518                 return err;
1519         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1520         if (err < 0)
1521                 return err;
1522
1523         /* Look for master conntrack of this expectation */
1524         h = nf_conntrack_find_get(&master_tuple, NULL);
1525         if (!h)
1526                 return -ENOENT;
1527         ct = nf_ct_tuplehash_to_ctrack(h);
1528         help = nfct_help(ct);
1529
1530         if (!help || !help->helper) {
1531                 /* such conntrack hasn't got any helper, abort */
1532                 err = -EINVAL;
1533                 goto out;
1534         }
1535
1536         exp = nf_conntrack_expect_alloc(ct);
1537         if (!exp) {
1538                 err = -ENOMEM;
1539                 goto out;
1540         }
1541
1542         exp->expectfn = NULL;
1543         exp->flags = 0;
1544         exp->master = ct;
1545         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1546         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1547
1548         err = nf_conntrack_expect_related(exp);
1549         nf_conntrack_expect_put(exp);
1550
1551 out:
1552         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1553         return err;
1554 }
1555
1556 static int
1557 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1558                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1559 {
1560         struct nf_conntrack_tuple tuple;
1561         struct nf_conntrack_expect *exp;
1562         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1563         u_int8_t u3 = nfmsg->nfgen_family;
1564         int err = 0;
1565
1566         DEBUGP("entered %s\n", __FUNCTION__);
1567
1568         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1569                 return -EINVAL;
1570
1571         if (!cda[CTA_EXPECT_TUPLE-1]
1572             || !cda[CTA_EXPECT_MASK-1]
1573             || !cda[CTA_EXPECT_MASTER-1])
1574                 return -EINVAL;
1575
1576         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1577         if (err < 0)
1578                 return err;
1579
1580         write_lock_bh(&nf_conntrack_lock);
1581         exp = __nf_conntrack_expect_find(&tuple);
1582
1583         if (!exp) {
1584                 write_unlock_bh(&nf_conntrack_lock);
1585                 err = -ENOENT;
1586                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1587                         err = ctnetlink_create_expect(cda, u3);
1588                 return err;
1589         }
1590
1591         err = -EEXIST;
1592         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1593                 err = ctnetlink_change_expect(exp, cda);
1594         write_unlock_bh(&nf_conntrack_lock);
1595
1596         DEBUGP("leaving\n");
1597
1598         return err;
1599 }
1600
1601 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1602 static struct notifier_block ctnl_notifier = {
1603         .notifier_call  = ctnetlink_conntrack_event,
1604 };
1605
1606 static struct notifier_block ctnl_notifier_exp = {
1607         .notifier_call  = ctnetlink_expect_event,
1608 };
1609 #endif
1610
1611 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1612         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1613                                             .attr_count = CTA_MAX, },
1614         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1615                                             .attr_count = CTA_MAX, },
1616         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1617                                             .attr_count = CTA_MAX, },
1618         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1619                                             .attr_count = CTA_MAX, },
1620 };
1621
1622 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1623         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1624                                             .attr_count = CTA_EXPECT_MAX, },
1625         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1626                                             .attr_count = CTA_EXPECT_MAX, },
1627         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1628                                             .attr_count = CTA_EXPECT_MAX, },
1629 };
1630
1631 static struct nfnetlink_subsystem ctnl_subsys = {
1632         .name                           = "conntrack",
1633         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1634         .cb_count                       = IPCTNL_MSG_MAX,
1635         .cb                             = ctnl_cb,
1636 };
1637
1638 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1639         .name                           = "conntrack_expect",
1640         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1641         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1642         .cb                             = ctnl_exp_cb,
1643 };
1644
1645 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1646 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1647
1648 static int __init ctnetlink_init(void)
1649 {
1650         int ret;
1651
1652         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1653         ret = nfnetlink_subsys_register(&ctnl_subsys);
1654         if (ret < 0) {
1655                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1656                 goto err_out;
1657         }
1658
1659         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1660         if (ret < 0) {
1661                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1662                 goto err_unreg_subsys;
1663         }
1664
1665 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1666         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1667         if (ret < 0) {
1668                 printk("ctnetlink_init: cannot register notifier.\n");
1669                 goto err_unreg_exp_subsys;
1670         }
1671
1672         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1673         if (ret < 0) {
1674                 printk("ctnetlink_init: cannot expect register notifier.\n");
1675                 goto err_unreg_notifier;
1676         }
1677 #endif
1678
1679         return 0;
1680
1681 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1682 err_unreg_notifier:
1683         nf_conntrack_unregister_notifier(&ctnl_notifier);
1684 err_unreg_exp_subsys:
1685         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1686 #endif
1687 err_unreg_subsys:
1688         nfnetlink_subsys_unregister(&ctnl_subsys);
1689 err_out:
1690         return ret;
1691 }
1692
1693 static void __exit ctnetlink_exit(void)
1694 {
1695         printk("ctnetlink: unregistering from nfnetlink.\n");
1696
1697 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1698         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1699         nf_conntrack_unregister_notifier(&ctnl_notifier);
1700 #endif
1701
1702         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1703         nfnetlink_subsys_unregister(&ctnl_subsys);
1704         return;
1705 }
1706
1707 module_init(ctnetlink_init);
1708 module_exit(ctnetlink_exit);