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         DEBUGP("entered %s\n", __FUNCTION__);
 411         return 0;
 412 }
 413
 414 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
 415
 416 static int
 417 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 418 {
 419         struct nf_conn *ct = NULL;
 420         struct nf_conntrack_tuple_hash *h;
 421         struct list_head *i;
 422         u_int32_t *id = (u_int32_t *) &cb->args[1];
 423         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 424         u_int8_t l3proto = nfmsg->nfgen_family;
 425
 426         DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__,
 427                         cb->args[0], *id);
 428
 429         read_lock_bh(&nf_conntrack_lock);
 430         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 431                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 432                         h = (struct nf_conntrack_tuple_hash *) i;
 433                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 434                                 continue;
 435                         ct = nf_ct_tuplehash_to_ctrack(h);
 436                         /* Dump entries of a given L3 protocol number.
 437                          * If it is not specified, ie. l3proto == 0,
 438                          * then dump everything. */
 439                         if (l3proto && L3PROTO(ct) != l3proto)
 440                                 continue;
 441                         if (ct->id <= *id)
 442                                 continue;
 443                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 444                                                 cb->nlh->nlmsg_seq,
 445                                                 IPCTNL_MSG_CT_NEW,
 446                                                 1, ct) < 0)
 447                                 goto out;
 448                         *id = ct->id;
 449                 }
 450         }
 451 out:
 452         read_unlock_bh(&nf_conntrack_lock);
 453
 454         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 455
 456         return skb->len;
 457 }
 458
 459 #ifdef CONFIG_NF_CT_ACCT
 460 static int
 461 ctnetlink_dump_table_w(struct sk_buff *skb, struct netlink_callback *cb)
 462 {
 463         struct nf_conn *ct = NULL;
 464         struct nf_conntrack_tuple_hash *h;
 465         struct list_head *i;
 466         u_int32_t *id = (u_int32_t *) &cb->args[1];
 467         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
 468         u_int8_t l3proto = nfmsg->nfgen_family;
 469
 470         DEBUGP("entered %s, last bucket=%u id=%u\n", __FUNCTION__,
 471                         cb->args[0], *id);
 472
 473         write_lock_bh(&nf_conntrack_lock);
 474         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) {
 475                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
 476                         h = (struct nf_conntrack_tuple_hash *) i;
 477                         if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 478                                 continue;
 479                         ct = nf_ct_tuplehash_to_ctrack(h);
 480                         if (l3proto && L3PROTO(ct) != l3proto)
 481                                 continue;
 482                         if (ct->id <= *id)
 483                                 continue;
 484                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 485                                                 cb->nlh->nlmsg_seq,
 486                                                 IPCTNL_MSG_CT_NEW,
 487                                                 1, ct) < 0)
 488                                 goto out;
 489                         *id = ct->id;
 490
 491                         memset(&ct->counters, 0, sizeof(ct->counters));
 492                 }
 493         }
 494 out:
 495         write_unlock_bh(&nf_conntrack_lock);
 496
 497         DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
 498
 499         return skb->len;
 500 }
 501 #endif
 502
 503 static inline int
 504 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
 505 {
 506         struct nfattr *tb[CTA_IP_MAX];
 507         struct nf_conntrack_l3proto *l3proto;
 508         int ret = 0;
 509
 510         DEBUGP("entered %s\n", __FUNCTION__);
 511
 512         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
 513
 514         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
 515
 516         if (likely(l3proto->nfattr_to_tuple))
 517                 ret = l3proto->nfattr_to_tuple(tb, tuple);
 518
 519         nf_ct_l3proto_put(l3proto);
 520
 521         DEBUGP("leaving\n");
 522
 523         return ret;
 524 }
 525
 526 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
 527         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
 528 };
 529
 530 static inline int
 531 ctnetlink_parse_tuple_proto(struct nfattr *attr,
 532                             struct nf_conntrack_tuple *tuple)
 533 {
 534         struct nfattr *tb[CTA_PROTO_MAX];
 535         struct nf_conntrack_protocol *proto;
 536         int ret = 0;
 537
 538         DEBUGP("entered %s\n", __FUNCTION__);
 539
 540         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
 541
 542         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
 543                 return -EINVAL;
 544
 545         if (!tb[CTA_PROTO_NUM-1])
 546                 return -EINVAL;
 547         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
 548
 549         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
 550
 551         if (likely(proto->nfattr_to_tuple))
 552                 ret = proto->nfattr_to_tuple(tb, tuple);
 553
 554         nf_ct_proto_put(proto);
 555
 556         return ret;
 557 }
 558
 559 static inline int
 560 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
 561                       enum ctattr_tuple type, u_int8_t l3num)
 562 {
 563         struct nfattr *tb[CTA_TUPLE_MAX];
 564         int err;
 565
 566         DEBUGP("entered %s\n", __FUNCTION__);
 567
 568         memset(tuple, 0, sizeof(*tuple));
 569
 570         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
 571
 572         if (!tb[CTA_TUPLE_IP-1])
 573                 return -EINVAL;
 574
 575         tuple->src.l3num = l3num;
 576
 577         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
 578         if (err < 0)
 579                 return err;
 580
 581         if (!tb[CTA_TUPLE_PROTO-1])
 582                 return -EINVAL;
 583
 584         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
 585         if (err < 0)
 586                 return err;
 587
 588         /* orig and expect tuples get DIR_ORIGINAL */
 589         if (type == CTA_TUPLE_REPLY)
 590                 tuple->dst.dir = IP_CT_DIR_REPLY;
 591         else
 592                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 593
 594         NF_CT_DUMP_TUPLE(tuple);
 595
 596         DEBUGP("leaving\n");
 597
 598         return 0;
 599 }
 600
 601 #ifdef CONFIG_IP_NF_NAT_NEEDED
 602 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
 603         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
 604         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
 605 };
 606
 607 static int ctnetlink_parse_nat_proto(struct nfattr *attr,
 608                                      const struct nf_conn *ct,
 609                                      struct ip_nat_range *range)
 610 {
 611         struct nfattr *tb[CTA_PROTONAT_MAX];
 612         struct ip_nat_protocol *npt;
 613
 614         DEBUGP("entered %s\n", __FUNCTION__);
 615
 616         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
 617
 618         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
 619                 return -EINVAL;
 620
 621         npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
 622
 623         if (!npt->nfattr_to_range) {
 624                 ip_nat_proto_put(npt);
 625                 return 0;
 626         }
 627
 628         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
 629         if (npt->nfattr_to_range(tb, range) > 0)
 630                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
 631
 632         ip_nat_proto_put(npt);
 633
 634         DEBUGP("leaving\n");
 635         return 0;
 636 }
 637
 638 static const size_t cta_min_nat[CTA_NAT_MAX] = {
 639         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
 640         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
 641 };
 642
 643 static inline int
 644 ctnetlink_parse_nat(struct nfattr *cda[],
 645                     const struct nf_conn *ct, struct ip_nat_range *range)
 646 {
 647         struct nfattr *tb[CTA_NAT_MAX];
 648         int err;
 649
 650         DEBUGP("entered %s\n", __FUNCTION__);
 651
 652         memset(range, 0, sizeof(*range));
 653
 654         nfattr_parse_nested(tb, CTA_NAT_MAX, cda[CTA_NAT-1]);
 655
 656         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
 657                 return -EINVAL;
 658
 659         if (tb[CTA_NAT_MINIP-1])
 660                 range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
 661
 662         if (!tb[CTA_NAT_MAXIP-1])
 663                 range->max_ip = range->min_ip;
 664         else
 665                 range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
 666
 667         if (range->min_ip)
 668                 range->flags |= IP_NAT_RANGE_MAP_IPS;
 669
 670         if (!tb[CTA_NAT_PROTO-1])
 671                 return 0;
 672
 673         err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
 674         if (err < 0)
 675                 return err;
 676
 677         DEBUGP("leaving\n");
 678         return 0;
 679 }
 680 #endif
 681
 682 static inline int
 683 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
 684 {
 685         struct nfattr *tb[CTA_HELP_MAX];
 686
 687         DEBUGP("entered %s\n", __FUNCTION__);
 688
 689         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
 690
 691         if (!tb[CTA_HELP_NAME-1])
 692                 return -EINVAL;
 693
 694         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
 695
 696         return 0;
 697 }
 698
 699 static const size_t cta_min[CTA_MAX] = {
 700         [CTA_STATUS-1]          = sizeof(u_int32_t),
 701         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
 702         [CTA_MARK-1]            = sizeof(u_int32_t),
 703         [CTA_USE-1]             = sizeof(u_int32_t),
 704         [CTA_ID-1]              = sizeof(u_int32_t)
 705 };
 706
 707 static int
 708 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 709                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 710 {
 711         struct nf_conntrack_tuple_hash *h;
 712         struct nf_conntrack_tuple tuple;
 713         struct nf_conn *ct;
 714         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 715         u_int8_t u3 = nfmsg->nfgen_family;
 716         int err = 0;
 717
 718         DEBUGP("entered %s\n", __FUNCTION__);
 719
 720         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 721                 return -EINVAL;
 722
 723         if (cda[CTA_TUPLE_ORIG-1])
 724                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 725         else if (cda[CTA_TUPLE_REPLY-1])
 726                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 727         else {
 728                 /* Flush the whole table */
 729                 nf_conntrack_flush();
 730                 return 0;
 731         }
 732
 733         if (err < 0)
 734                 return err;
 735
 736         h = nf_conntrack_find_get(&tuple, NULL);
 737         if (!h) {
 738                 DEBUGP("tuple not found in conntrack hash\n");
 739                 return -ENOENT;
 740         }
 741
 742         ct = nf_ct_tuplehash_to_ctrack(h);
 743
 744         if (cda[CTA_ID-1]) {
 745                 u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1]));
 746                 if (ct->id != id) {
 747                         nf_ct_put(ct);
 748                         return -ENOENT;
 749                 }
 750         }
 751         if (del_timer(&ct->timeout))
 752                 ct->timeout.function((unsigned long)ct);
 753
 754         nf_ct_put(ct);
 755         DEBUGP("leaving\n");
 756
 757         return 0;
 758 }
 759
 760 static int
 761 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 762                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
 763 {
 764         struct nf_conntrack_tuple_hash *h;
 765         struct nf_conntrack_tuple tuple;
 766         struct nf_conn *ct;
 767         struct sk_buff *skb2 = NULL;
 768         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
 769         u_int8_t u3 = nfmsg->nfgen_family;
 770         int err = 0;
 771
 772         DEBUGP("entered %s\n", __FUNCTION__);
 773
 774         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 775                 u32 rlen;
 776
 777                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) ==
 778                                         IPCTNL_MSG_CT_GET_CTRZERO) {
 779 #ifdef CONFIG_NF_CT_ACCT
 780                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 781                                                 ctnetlink_dump_table_w,
 782                                                 ctnetlink_done)) != 0)
 783                                 return -EINVAL;
 784 #else
 785                         return -ENOTSUPP;
 786 #endif
 787                 } else {
 788                         if ((*errp = netlink_dump_start(ctnl, skb, nlh,
 789                                                         ctnetlink_dump_table,
 790                                                         ctnetlink_done)) != 0)
 791                         return -EINVAL;
 792                 }
 793
 794                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 795                 if (rlen > skb->len)
 796                         rlen = skb->len;
 797                 skb_pull(skb, rlen);
 798                 return 0;
 799         }
 800
 801         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
 802                 return -EINVAL;
 803
 804         if (cda[CTA_TUPLE_ORIG-1])
 805                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 806         else if (cda[CTA_TUPLE_REPLY-1])
 807                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 808         else
 809                 return -EINVAL;
 810
 811         if (err < 0)
 812                 return err;
 813
 814         h = nf_conntrack_find_get(&tuple, NULL);
 815         if (!h) {
 816                 DEBUGP("tuple not found in conntrack hash");
 817                 return -ENOENT;
 818         }
 819         DEBUGP("tuple found\n");
 820         ct = nf_ct_tuplehash_to_ctrack(h);
 821
 822         err = -ENOMEM;
 823         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 824         if (!skb2) {
 825                 nf_ct_put(ct);
 826                 return -ENOMEM;
 827         }
 828         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
 829
 830         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
 831                                   IPCTNL_MSG_CT_NEW, 1, ct);
 832         nf_ct_put(ct);
 833         if (err <= 0)
 834                 goto free;
 835
 836         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
 837         if (err < 0)
 838                 goto out;
 839
 840         DEBUGP("leaving\n");
 841         return 0;
 842
 843 free:
 844         kfree_skb(skb2);
 845 out:
 846         return err;
 847 }
 848
 849 static inline int
 850 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
 851 {
 852         unsigned long d;
 853         unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1]));
 854         d = ct->status ^ status;
 855
 856         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
 857                 /* unchangeable */
 858                 return -EINVAL;
 859
 860         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
 861                 /* SEEN_REPLY bit can only be set */
 862                 return -EINVAL;
 863
 864
 865         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
 866                 /* ASSURED bit can only be set */
 867                 return -EINVAL;
 868
 869         if (cda[CTA_NAT-1]) {
 870 #ifndef CONFIG_IP_NF_NAT_NEEDED
 871                 return -EINVAL;
 872 #else
 873                 unsigned int hooknum;
 874                 struct ip_nat_range range;
 875
 876                 if (ctnetlink_parse_nat(cda, ct, &range) < 0)
 877                         return -EINVAL;
 878
 879                 DEBUGP("NAT: %u.%u.%u.%u-%u.%u.%u.%u:%u-%u\n",
 880                        NIPQUAD(range.min_ip), NIPQUAD(range.max_ip),
 881                        htons(range.min.all), htons(range.max.all));
 882
 883                 /* This is tricky but it works. ip_nat_setup_info needs the
 884                  * hook number as parameter, so let's do the correct
 885                  * conversion and run away */
 886                 if (status & IPS_SRC_NAT_DONE)
 887                         hooknum = NF_IP_POST_ROUTING; /* IP_NAT_MANIP_SRC */
 888                 else if (status & IPS_DST_NAT_DONE)
 889                         hooknum = NF_IP_PRE_ROUTING;  /* IP_NAT_MANIP_DST */
 890                 else
 891                         return -EINVAL; /* Missing NAT flags */
 892
 893                 DEBUGP("NAT status: %lu\n",
 894                        status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK));
 895
 896                 if (ip_nat_initialized(ct, HOOK2MANIP(hooknum)))
 897                         return -EEXIST;
 898                 ip_nat_setup_info(ct, &range, hooknum);
 899
 900                 DEBUGP("NAT status after setup_info: %lu\n",
 901                        ct->status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK));
 902 #endif
 903         }
 904
 905         /* Be careful here, modifying NAT bits can screw up things,
 906          * so don't let users modify them directly if they don't pass
 907          * ip_nat_range. */
 908         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
 909         return 0;
 910 }
 911
 912
 913 static inline int
 914 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 915 {
 916         struct nf_conntrack_helper *helper;
 917         struct nf_conn_help *help = nfct_help(ct);
 918         char *helpname;
 919         int err;
 920
 921         DEBUGP("entered %s\n", __FUNCTION__);
 922
 923         if (!help) {
 924                 /* FIXME: we need to reallocate and rehash */
 925                 return -EBUSY;
 926         }
 927
 928         /* don't change helper of sibling connections */
 929         if (ct->master)
 930                 return -EINVAL;
 931
 932         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
 933         if (err < 0)
 934                 return err;
 935
 936         helper = __nf_conntrack_helper_find_byname(helpname);
 937         if (!helper) {
 938                 if (!strcmp(helpname, ""))
 939                         helper = NULL;
 940                 else
 941                         return -EINVAL;
 942         }
 943
 944         if (help->helper) {
 945                 if (!helper) {
 946                         /* we had a helper before ... */
 947                         nf_ct_remove_expectations(ct);
 948                         help->helper = NULL;
 949                 } else {
 950                         /* need to zero data of old helper */
 951                         memset(&help->help, 0, sizeof(help->help));
 952                 }
 953         }
 954
 955         help->helper = helper;
 956
 957         return 0;
 958 }
 959
 960 static inline int
 961 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
 962 {
 963         u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
 964
 965         if (!del_timer(&ct->timeout))
 966                 return -ETIME;
 967
 968         ct->timeout.expires = jiffies + timeout * HZ;
 969         add_timer(&ct->timeout);
 970
 971         return 0;
 972 }
 973
 974 static inline int
 975 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
 976 {
 977         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
 978         struct nf_conntrack_protocol *proto;
 979         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
 980         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 981         int err = 0;
 982
 983         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
 984
 985         proto = nf_ct_proto_find_get(l3num, npt);
 986
 987         if (proto->from_nfattr)
 988                 err = proto->from_nfattr(tb, ct);
 989         nf_ct_proto_put(proto);
 990
 991         return err;
 992 }
 993
 994 static int
 995 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
 996 {
 997         int err;
 998
 999         DEBUGP("entered %s\n", __FUNCTION__);
1000
1001         if (cda[CTA_HELP-1]) {
1002                 err = ctnetlink_change_helper(ct, cda);
1003                 if (err < 0)
1004                         return err;
1005         }
1006
1007         if (cda[CTA_TIMEOUT-1]) {
1008                 err = ctnetlink_change_timeout(ct, cda);
1009                 if (err < 0)
1010                         return err;
1011         }
1012
1013         if (cda[CTA_STATUS-1]) {
1014                 err = ctnetlink_change_status(ct, cda);
1015                 if (err < 0)
1016                         return err;
1017         }
1018
1019         if (cda[CTA_PROTOINFO-1]) {
1020                 err = ctnetlink_change_protoinfo(ct, cda);
1021                 if (err < 0)
1022                         return err;
1023         }
1024
1025 #if defined(CONFIG_NF_CONNTRACK_MARK)
1026         if (cda[CTA_MARK-1])
1027                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1028 #endif
1029
1030         DEBUGP("all done\n");
1031         return 0;
1032 }
1033
1034 static int
1035 ctnetlink_create_conntrack(struct nfattr *cda[],
1036                            struct nf_conntrack_tuple *otuple,
1037                            struct nf_conntrack_tuple *rtuple)
1038 {
1039         struct nf_conn *ct;
1040         int err = -EINVAL;
1041
1042         DEBUGP("entered %s\n", __FUNCTION__);
1043
1044         ct = nf_conntrack_alloc(otuple, rtuple);
1045         if (ct == NULL || IS_ERR(ct))
1046                 return -ENOMEM;
1047
1048         if (!cda[CTA_TIMEOUT-1])
1049                 goto err;
1050         ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1]));
1051
1052         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1053         ct->status |= IPS_CONFIRMED;
1054
1055         err = ctnetlink_change_status(ct, cda);
1056         if (err < 0)
1057                 goto err;
1058
1059         if (cda[CTA_PROTOINFO-1]) {
1060                 err = ctnetlink_change_protoinfo(ct, cda);
1061                 if (err < 0)
1062                         return err;
1063         }
1064
1065 #if defined(CONFIG_NF_CONNTRACK_MARK)
1066         if (cda[CTA_MARK-1])
1067                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
1068 #endif
1069
1070         add_timer(&ct->timeout);
1071         nf_conntrack_hash_insert(ct);
1072
1073         DEBUGP("conntrack with id %u inserted\n", ct->id);
1074         return 0;
1075
1076 err:
1077         nf_conntrack_free(ct);
1078         return err;
1079 }
1080
1081 static int
1082 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1083                         struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1084 {
1085         struct nf_conntrack_tuple otuple, rtuple;
1086         struct nf_conntrack_tuple_hash *h = NULL;
1087         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1088         u_int8_t u3 = nfmsg->nfgen_family;
1089         int err = 0;
1090
1091         DEBUGP("entered %s\n", __FUNCTION__);
1092
1093         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1094                 return -EINVAL;
1095
1096         if (cda[CTA_TUPLE_ORIG-1]) {
1097                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1098                 if (err < 0)
1099                         return err;
1100         }
1101
1102         if (cda[CTA_TUPLE_REPLY-1]) {
1103                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1104                 if (err < 0)
1105                         return err;
1106         }
1107
1108         write_lock_bh(&nf_conntrack_lock);
1109         if (cda[CTA_TUPLE_ORIG-1])
1110                 h = __nf_conntrack_find(&otuple, NULL);
1111         else if (cda[CTA_TUPLE_REPLY-1])
1112                 h = __nf_conntrack_find(&rtuple, NULL);
1113
1114         if (h == NULL) {
1115                 write_unlock_bh(&nf_conntrack_lock);
1116                 DEBUGP("no such conntrack, create new\n");
1117                 err = -ENOENT;
1118                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1119                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1120                 return err;
1121         }
1122         /* implicit 'else' */
1123
1124         /* we only allow nat config for new conntracks */
1125         if (cda[CTA_NAT-1]) {
1126                 err = -EINVAL;
1127                 goto out_unlock;
1128         }
1129
1130         /* We manipulate the conntrack inside the global conntrack table lock,
1131          * so there's no need to increase the refcount */
1132         DEBUGP("conntrack found\n");
1133         err = -EEXIST;
1134         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1135                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1136
1137 out_unlock:
1138         write_unlock_bh(&nf_conntrack_lock);
1139         return err;
1140 }
1141
1142 /***********************************************************************
1143  * EXPECT
1144  ***********************************************************************/
1145
1146 static inline int
1147 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1148                          const struct nf_conntrack_tuple *tuple,
1149                          enum ctattr_expect type)
1150 {
1151         struct nfattr *nest_parms = NFA_NEST(skb, type);
1152
1153         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1154                 goto nfattr_failure;
1155
1156         NFA_NEST_END(skb, nest_parms);
1157
1158         return 0;
1159
1160 nfattr_failure:
1161         return -1;
1162 }
1163
1164 static inline int
1165 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1166                         const struct nf_conntrack_tuple *tuple,
1167                         const struct nf_conntrack_tuple *mask)
1168 {
1169         int ret;
1170         struct nf_conntrack_l3proto *l3proto;
1171         struct nf_conntrack_protocol *proto;
1172         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1173
1174         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1175         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1176         nf_ct_l3proto_put(l3proto);
1177
1178         if (unlikely(ret < 0))
1179                 goto nfattr_failure;
1180
1181         proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1182         ret = ctnetlink_dump_tuples_proto(skb, mask, proto);
1183         nf_ct_proto_put(proto);
1184         if (unlikely(ret < 0))
1185                 goto nfattr_failure;
1186
1187         NFA_NEST_END(skb, nest_parms);
1188
1189         return 0;
1190
1191 nfattr_failure:
1192         return -1;
1193 }
1194
1195 static inline int
1196 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1197                           const struct nf_conntrack_expect *exp)
1198 {
1199         struct nf_conn *master = exp->master;
1200         u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1201         u_int32_t id = htonl(exp->id);
1202
1203         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1204                 goto nfattr_failure;
1205         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1206                 goto nfattr_failure;
1207         if (ctnetlink_exp_dump_tuple(skb,
1208                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1209                                  CTA_EXPECT_MASTER) < 0)
1210                 goto nfattr_failure;
1211
1212         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1213         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1214
1215         return 0;
1216
1217 nfattr_failure:
1218         return -1;
1219 }
1220
1221 static int
1222 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1223                     int event,
1224                     int nowait,
1225                     const struct nf_conntrack_expect *exp)
1226 {
1227         struct nlmsghdr *nlh;
1228         struct nfgenmsg *nfmsg;
1229         unsigned char *b;
1230
1231         b = skb->tail;
1232
1233         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1234         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1235         nfmsg  = NLMSG_DATA(nlh);
1236
1237         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1238         nfmsg->nfgen_family = exp->tuple.src.l3num;
1239         nfmsg->version      = NFNETLINK_V0;
1240         nfmsg->res_id       = 0;
1241
1242         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1243                 goto nfattr_failure;
1244
1245         nlh->nlmsg_len = skb->tail - b;
1246         return skb->len;
1247
1248 nlmsg_failure:
1249 nfattr_failure:
1250         skb_trim(skb, b - skb->data);
1251         return -1;
1252 }
1253
1254 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1255 static int ctnetlink_expect_event(struct notifier_block *this,
1256                                   unsigned long events, void *ptr)
1257 {
1258         struct nlmsghdr *nlh;
1259         struct nfgenmsg *nfmsg;
1260         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1261         struct sk_buff *skb;
1262         unsigned int type;
1263         unsigned char *b;
1264         int flags = 0;
1265
1266         if (events & IPEXP_NEW) {
1267                 type = IPCTNL_MSG_EXP_NEW;
1268                 flags = NLM_F_CREATE|NLM_F_EXCL;
1269         } else
1270                 return NOTIFY_DONE;
1271
1272         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1273         if (!skb)
1274                 return NOTIFY_DONE;
1275
1276         b = skb->tail;
1277
1278         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1279         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1280         nfmsg = NLMSG_DATA(nlh);
1281
1282         nlh->nlmsg_flags    = flags;
1283         nfmsg->nfgen_family = exp->tuple.src.l3num;
1284         nfmsg->version      = NFNETLINK_V0;
1285         nfmsg->res_id       = 0;
1286
1287         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1288                 goto nfattr_failure;
1289
1290         nlh->nlmsg_len = skb->tail - b;
1291         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1292         return NOTIFY_DONE;
1293
1294 nlmsg_failure:
1295 nfattr_failure:
1296         kfree_skb(skb);
1297         return NOTIFY_DONE;
1298 }
1299 #endif
1300
1301 static int
1302 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1303 {
1304         struct nf_conntrack_expect *exp = NULL;
1305         struct list_head *i;
1306         u_int32_t *id = (u_int32_t *) &cb->args[0];
1307         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1308         u_int8_t l3proto = nfmsg->nfgen_family;
1309
1310         DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id);
1311
1312         read_lock_bh(&nf_conntrack_lock);
1313         list_for_each_prev(i, &nf_conntrack_expect_list) {
1314                 exp = (struct nf_conntrack_expect *) i;
1315                 if (l3proto && exp->tuple.src.l3num != l3proto)
1316                         continue;
1317                 if (exp->id <= *id)
1318                         continue;
1319                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1320                                             cb->nlh->nlmsg_seq,
1321                                             IPCTNL_MSG_EXP_NEW,
1322                                             1, exp) < 0)
1323                         goto out;
1324                 *id = exp->id;
1325         }
1326 out:
1327         read_unlock_bh(&nf_conntrack_lock);
1328
1329         DEBUGP("leaving, last id=%llu\n", *id);
1330
1331         return skb->len;
1332 }
1333
1334 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1335         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1336         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1337 };
1338
1339 static int
1340 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1341                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1342 {
1343         struct nf_conntrack_tuple tuple;
1344         struct nf_conntrack_expect *exp;
1345         struct sk_buff *skb2;
1346         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1347         u_int8_t u3 = nfmsg->nfgen_family;
1348         int err = 0;
1349
1350         DEBUGP("entered %s\n", __FUNCTION__);
1351
1352         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1353                 return -EINVAL;
1354
1355         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1356                 u32 rlen;
1357
1358                 if ((*errp = netlink_dump_start(ctnl, skb, nlh,
1359                                                 ctnetlink_exp_dump_table,
1360                                                 ctnetlink_done)) != 0)
1361                         return -EINVAL;
1362                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1363                 if (rlen > skb->len)
1364                         rlen = skb->len;
1365                 skb_pull(skb, rlen);
1366                 return 0;
1367         }
1368
1369         if (cda[CTA_EXPECT_MASTER-1])
1370                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1371         else
1372                 return -EINVAL;
1373
1374         if (err < 0)
1375                 return err;
1376
1377         exp = nf_conntrack_expect_find(&tuple);
1378         if (!exp)
1379                 return -ENOENT;
1380
1381         if (cda[CTA_EXPECT_ID-1]) {
1382                 u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1383                 if (exp->id != ntohl(id)) {
1384                         nf_conntrack_expect_put(exp);
1385                         return -ENOENT;
1386                 }
1387         }
1388
1389         err = -ENOMEM;
1390         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1391         if (!skb2)
1392                 goto out;
1393         NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid;
1394
1395         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1396                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1397                                       1, exp);
1398         if (err <= 0)
1399                 goto free;
1400
1401         nf_conntrack_expect_put(exp);
1402
1403         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1404
1405 free:
1406         kfree_skb(skb2);
1407 out:
1408         nf_conntrack_expect_put(exp);
1409         return err;
1410 }
1411
1412 static int
1413 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1414                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1415 {
1416         struct nf_conntrack_expect *exp, *tmp;
1417         struct nf_conntrack_tuple tuple;
1418         struct nf_conntrack_helper *h;
1419         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1420         u_int8_t u3 = nfmsg->nfgen_family;
1421         int err;
1422
1423         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1424                 return -EINVAL;
1425
1426         if (cda[CTA_EXPECT_TUPLE-1]) {
1427                 /* delete a single expect by tuple */
1428                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1429                 if (err < 0)
1430                         return err;
1431
1432                 /* bump usage count to 2 */
1433                 exp = nf_conntrack_expect_find(&tuple);
1434                 if (!exp)
1435                         return -ENOENT;
1436
1437                 if (cda[CTA_EXPECT_ID-1]) {
1438                         u_int32_t id =
1439                                 *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1440                         if (exp->id != ntohl(id)) {
1441                                 nf_conntrack_expect_put(exp);
1442                                 return -ENOENT;
1443                         }
1444                 }
1445
1446                 /* after list removal, usage count == 1 */
1447                 nf_conntrack_unexpect_related(exp);
1448                 /* have to put what we 'get' above.
1449                  * after this line usage count == 0 */
1450                 nf_conntrack_expect_put(exp);
1451         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1452                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1453
1454                 /* delete all expectations for this helper */
1455                 write_lock_bh(&nf_conntrack_lock);
1456                 h = __nf_conntrack_helper_find_byname(name);
1457                 if (!h) {
1458                         write_unlock_bh(&nf_conntrack_lock);
1459                         return -EINVAL;
1460                 }
1461                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1462                                          list) {
1463                         struct nf_conn_help *m_help = nfct_help(exp->master);
1464                         if (m_help->helper == h
1465                             && del_timer(&exp->timeout)) {
1466                                 nf_ct_unlink_expect(exp);
1467                                 nf_conntrack_expect_put(exp);
1468                         }
1469                 }
1470                 write_unlock_bh(&nf_conntrack_lock);
1471         } else {
1472                 /* This basically means we have to flush everything*/
1473                 write_lock_bh(&nf_conntrack_lock);
1474                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1475                                          list) {
1476                         if (del_timer(&exp->timeout)) {
1477                                 nf_ct_unlink_expect(exp);
1478                                 nf_conntrack_expect_put(exp);
1479                         }
1480                 }
1481                 write_unlock_bh(&nf_conntrack_lock);
1482         }
1483
1484         return 0;
1485 }
1486 static int
1487 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1488 {
1489         return -EOPNOTSUPP;
1490 }
1491
1492 static int
1493 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1494 {
1495         struct nf_conntrack_tuple tuple, mask, master_tuple;
1496         struct nf_conntrack_tuple_hash *h = NULL;
1497         struct nf_conntrack_expect *exp;
1498         struct nf_conn *ct;
1499         struct nf_conn_help *help;
1500         int err = 0;
1501
1502         DEBUGP("entered %s\n", __FUNCTION__);
1503
1504         /* caller guarantees that those three CTA_EXPECT_* exist */
1505         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1506         if (err < 0)
1507                 return err;
1508         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1509         if (err < 0)
1510                 return err;
1511         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1512         if (err < 0)
1513                 return err;
1514
1515         /* Look for master conntrack of this expectation */
1516         h = nf_conntrack_find_get(&master_tuple, NULL);
1517         if (!h)
1518                 return -ENOENT;
1519         ct = nf_ct_tuplehash_to_ctrack(h);
1520         help = nfct_help(ct);
1521
1522         if (!help || !help->helper) {
1523                 /* such conntrack hasn't got any helper, abort */
1524                 err = -EINVAL;
1525                 goto out;
1526         }
1527
1528         exp = nf_conntrack_expect_alloc(ct);
1529         if (!exp) {
1530                 err = -ENOMEM;
1531                 goto out;
1532         }
1533
1534         exp->expectfn = NULL;
1535         exp->flags = 0;
1536         exp->master = ct;
1537         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1538         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1539
1540         err = nf_conntrack_expect_related(exp);
1541         nf_conntrack_expect_put(exp);
1542
1543 out:
1544         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1545         return err;
1546 }
1547
1548 static int
1549 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1550                      struct nlmsghdr *nlh, struct nfattr *cda[], int *errp)
1551 {
1552         struct nf_conntrack_tuple tuple;
1553         struct nf_conntrack_expect *exp;
1554         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1555         u_int8_t u3 = nfmsg->nfgen_family;
1556         int err = 0;
1557
1558         DEBUGP("entered %s\n", __FUNCTION__);
1559
1560         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1561                 return -EINVAL;
1562
1563         if (!cda[CTA_EXPECT_TUPLE-1]
1564             || !cda[CTA_EXPECT_MASK-1]
1565             || !cda[CTA_EXPECT_MASTER-1])
1566                 return -EINVAL;
1567
1568         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1569         if (err < 0)
1570                 return err;
1571
1572         write_lock_bh(&nf_conntrack_lock);
1573         exp = __nf_conntrack_expect_find(&tuple);
1574
1575         if (!exp) {
1576                 write_unlock_bh(&nf_conntrack_lock);
1577                 err = -ENOENT;
1578                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1579                         err = ctnetlink_create_expect(cda, u3);
1580                 return err;
1581         }
1582
1583         err = -EEXIST;
1584         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1585                 err = ctnetlink_change_expect(exp, cda);
1586         write_unlock_bh(&nf_conntrack_lock);
1587
1588         DEBUGP("leaving\n");
1589
1590         return err;
1591 }
1592
1593 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1594 static struct notifier_block ctnl_notifier = {
1595         .notifier_call  = ctnetlink_conntrack_event,
1596 };
1597
1598 static struct notifier_block ctnl_notifier_exp = {
1599         .notifier_call  = ctnetlink_expect_event,
1600 };
1601 #endif
1602
1603 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1604         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1605                                             .attr_count = CTA_MAX, },
1606         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1607                                             .attr_count = CTA_MAX, },
1608         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1609                                             .attr_count = CTA_MAX, },
1610         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1611                                             .attr_count = CTA_MAX, },
1612 };
1613
1614 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1615         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1616                                             .attr_count = CTA_EXPECT_MAX, },
1617         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1618                                             .attr_count = CTA_EXPECT_MAX, },
1619         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1620                                             .attr_count = CTA_EXPECT_MAX, },
1621 };
1622
1623 static struct nfnetlink_subsystem ctnl_subsys = {
1624         .name                           = "conntrack",
1625         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1626         .cb_count                       = IPCTNL_MSG_MAX,
1627         .cb                             = ctnl_cb,
1628 };
1629
1630 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1631         .name                           = "conntrack_expect",
1632         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1633         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1634         .cb                             = ctnl_exp_cb,
1635 };
1636
1637 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1638 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1639
1640 static int __init ctnetlink_init(void)
1641 {
1642         int ret;
1643
1644         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1645         ret = nfnetlink_subsys_register(&ctnl_subsys);
1646         if (ret < 0) {
1647                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1648                 goto err_out;
1649         }
1650
1651         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1652         if (ret < 0) {
1653                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1654                 goto err_unreg_subsys;
1655         }
1656
1657 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1658         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1659         if (ret < 0) {
1660                 printk("ctnetlink_init: cannot register notifier.\n");
1661                 goto err_unreg_exp_subsys;
1662         }
1663
1664         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1665         if (ret < 0) {
1666                 printk("ctnetlink_init: cannot expect register notifier.\n");
1667                 goto err_unreg_notifier;
1668         }
1669 #endif
1670
1671         return 0;
1672
1673 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1674 err_unreg_notifier:
1675         nf_conntrack_unregister_notifier(&ctnl_notifier);
1676 err_unreg_exp_subsys:
1677         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1678 #endif
1679 err_unreg_subsys:
1680         nfnetlink_subsys_unregister(&ctnl_subsys);
1681 err_out:
1682         return ret;
1683 }
1684
1685 static void __exit ctnetlink_exit(void)
1686 {
1687         printk("ctnetlink: unregistering from nfnetlink.\n");
1688
1689 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1690         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1691         nf_conntrack_unregister_notifier(&ctnl_notifier);
1692 #endif
1693
1694         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1695         nfnetlink_subsys_unregister(&ctnl_subsys);
1696         return;
1697 }
1698
1699 module_init(ctnetlink_init);
1700 module_exit(ctnetlink_exit);