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) 2005-2011 by Pablo Neira Ayuso <pablo@netfilter.org>
   8  *
   9  * Initial connection tracking via netlink development funded and
  10  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
  11  *
  12  * Further development of this code funded by Astaro AG (http://www.astaro.com)
  13  *
  14  * This software may be used and distributed according to the terms
  15  * of the GNU General Public License, incorporated herein by reference.
  16  */
  17
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/rculist.h>
  22 #include <linux/rculist_nulls.h>
  23 #include <linux/types.h>
  24 #include <linux/timer.h>
  25 #include <linux/security.h>
  26 #include <linux/skbuff.h>
  27 #include <linux/errno.h>
  28 #include <linux/netlink.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/slab.h>
  32
  33 #include <linux/netfilter.h>
  34 #include <net/netlink.h>
  35 #include <net/sock.h>
  36 #include <net/netfilter/nf_conntrack.h>
  37 #include <net/netfilter/nf_conntrack_core.h>
  38 #include <net/netfilter/nf_conntrack_expect.h>
  39 #include <net/netfilter/nf_conntrack_helper.h>
  40 #include <net/netfilter/nf_conntrack_l3proto.h>
  41 #include <net/netfilter/nf_conntrack_l4proto.h>
  42 #include <net/netfilter/nf_conntrack_tuple.h>
  43 #include <net/netfilter/nf_conntrack_acct.h>
  44 #include <net/netfilter/nf_conntrack_zones.h>
  45 #include <net/netfilter/nf_conntrack_timestamp.h>
  46 #ifdef CONFIG_NF_NAT_NEEDED
  47 #include <net/netfilter/nf_nat_core.h>
  48 #include <net/netfilter/nf_nat_protocol.h>
  49 #endif
  50
  51 #include <linux/netfilter/nfnetlink.h>
  52 #include <linux/netfilter/nfnetlink_conntrack.h>
  53
  54 MODULE_LICENSE("GPL");
  55
  56 static char __initdata version[] = "0.93";
  57
  58 static inline int
  59 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
  60                             const struct nf_conntrack_tuple *tuple,
  61                             struct nf_conntrack_l4proto *l4proto)
  62 {
  63         int ret = 0;
  64         struct nlattr *nest_parms;
  65
  66         nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO | NLA_F_NESTED);
  67         if (!nest_parms)
  68                 goto nla_put_failure;
  69         NLA_PUT_U8(skb, CTA_PROTO_NUM, tuple->dst.protonum);
  70
  71         if (likely(l4proto->tuple_to_nlattr))
  72                 ret = l4proto->tuple_to_nlattr(skb, tuple);
  73
  74         nla_nest_end(skb, nest_parms);
  75
  76         return ret;
  77
  78 nla_put_failure:
  79         return -1;
  80 }
  81
  82 static inline int
  83 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
  84                          const struct nf_conntrack_tuple *tuple,
  85                          struct nf_conntrack_l3proto *l3proto)
  86 {
  87         int ret = 0;
  88         struct nlattr *nest_parms;
  89
  90         nest_parms = nla_nest_start(skb, CTA_TUPLE_IP | NLA_F_NESTED);
  91         if (!nest_parms)
  92                 goto nla_put_failure;
  93
  94         if (likely(l3proto->tuple_to_nlattr))
  95                 ret = l3proto->tuple_to_nlattr(skb, tuple);
  96
  97         nla_nest_end(skb, nest_parms);
  98
  99         return ret;
 100
 101 nla_put_failure:
 102         return -1;
 103 }
 104
 105 static int
 106 ctnetlink_dump_tuples(struct sk_buff *skb,
 107                       const struct nf_conntrack_tuple *tuple)
 108 {
 109         int ret;
 110         struct nf_conntrack_l3proto *l3proto;
 111         struct nf_conntrack_l4proto *l4proto;
 112
 113         l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
 114         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
 115
 116         if (unlikely(ret < 0))
 117                 return ret;
 118
 119         l4proto = __nf_ct_l4proto_find(tuple->src.l3num, tuple->dst.protonum);
 120         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
 121
 122         return ret;
 123 }
 124
 125 static inline int
 126 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
 127 {
 128         NLA_PUT_BE32(skb, CTA_STATUS, htonl(ct->status));
 129         return 0;
 130
 131 nla_put_failure:
 132         return -1;
 133 }
 134
 135 static inline int
 136 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
 137 {
 138         long timeout = ((long)ct->timeout.expires - (long)jiffies) / HZ;
 139
 140         if (timeout < 0)
 141                 timeout = 0;
 142
 143         NLA_PUT_BE32(skb, CTA_TIMEOUT, htonl(timeout));
 144         return 0;
 145
 146 nla_put_failure:
 147         return -1;
 148 }
 149
 150 static inline int
 151 ctnetlink_dump_protoinfo(struct sk_buff *skb, struct nf_conn *ct)
 152 {
 153         struct nf_conntrack_l4proto *l4proto;
 154         struct nlattr *nest_proto;
 155         int ret;
 156
 157         l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
 158         if (!l4proto->to_nlattr)
 159                 return 0;
 160
 161         nest_proto = nla_nest_start(skb, CTA_PROTOINFO | NLA_F_NESTED);
 162         if (!nest_proto)
 163                 goto nla_put_failure;
 164
 165         ret = l4proto->to_nlattr(skb, nest_proto, ct);
 166
 167         nla_nest_end(skb, nest_proto);
 168
 169         return ret;
 170
 171 nla_put_failure:
 172         return -1;
 173 }
 174
 175 static inline int
 176 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 177 {
 178         struct nlattr *nest_helper;
 179         const struct nf_conn_help *help = nfct_help(ct);
 180         struct nf_conntrack_helper *helper;
 181
 182         if (!help)
 183                 return 0;
 184
 185         helper = rcu_dereference(help->helper);
 186         if (!helper)
 187                 goto out;
 188
 189         nest_helper = nla_nest_start(skb, CTA_HELP | NLA_F_NESTED);
 190         if (!nest_helper)
 191                 goto nla_put_failure;
 192         NLA_PUT_STRING(skb, CTA_HELP_NAME, helper->name);
 193
 194         if (helper->to_nlattr)
 195                 helper->to_nlattr(skb, ct);
 196
 197         nla_nest_end(skb, nest_helper);
 198 out:
 199         return 0;
 200
 201 nla_put_failure:
 202         return -1;
 203 }
 204
 205 static int
 206 dump_counters(struct sk_buff *skb, u64 pkts, u64 bytes,
 207               enum ip_conntrack_dir dir)
 208 {
 209         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
 210         struct nlattr *nest_count;
 211
 212         nest_count = nla_nest_start(skb, type | NLA_F_NESTED);
 213         if (!nest_count)
 214                 goto nla_put_failure;
 215
 216         NLA_PUT_BE64(skb, CTA_COUNTERS_PACKETS, cpu_to_be64(pkts));
 217         NLA_PUT_BE64(skb, CTA_COUNTERS_BYTES, cpu_to_be64(bytes));
 218
 219         nla_nest_end(skb, nest_count);
 220
 221         return 0;
 222
 223 nla_put_failure:
 224         return -1;
 225 }
 226
 227 static int
 228 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
 229                         enum ip_conntrack_dir dir, int type)
 230 {
 231         struct nf_conn_counter *acct;
 232         u64 pkts, bytes;
 233
 234         acct = nf_conn_acct_find(ct);
 235         if (!acct)
 236                 return 0;
 237
 238         if (type == IPCTNL_MSG_CT_GET_CTRZERO) {
 239                 pkts = atomic64_xchg(&acct[dir].packets, 0);
 240                 bytes = atomic64_xchg(&acct[dir].bytes, 0);
 241         } else {
 242                 pkts = atomic64_read(&acct[dir].packets);
 243                 bytes = atomic64_read(&acct[dir].bytes);
 244         }
 245         return dump_counters(skb, pkts, bytes, dir);
 246 }
 247
 248 static int
 249 ctnetlink_dump_timestamp(struct sk_buff *skb, const struct nf_conn *ct)
 250 {
 251         struct nlattr *nest_count;
 252         const struct nf_conn_tstamp *tstamp;
 253
 254         tstamp = nf_conn_tstamp_find(ct);
 255         if (!tstamp)
 256                 return 0;
 257
 258         nest_count = nla_nest_start(skb, CTA_TIMESTAMP | NLA_F_NESTED);
 259         if (!nest_count)
 260                 goto nla_put_failure;
 261
 262         NLA_PUT_BE64(skb, CTA_TIMESTAMP_START, cpu_to_be64(tstamp->start));
 263         if (tstamp->stop != 0) {
 264                 NLA_PUT_BE64(skb, CTA_TIMESTAMP_STOP,
 265                              cpu_to_be64(tstamp->stop));
 266         }
 267         nla_nest_end(skb, nest_count);
 268
 269         return 0;
 270
 271 nla_put_failure:
 272         return -1;
 273 }
 274
 275 #ifdef CONFIG_NF_CONNTRACK_MARK
 276 static inline int
 277 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 278 {
 279         NLA_PUT_BE32(skb, CTA_MARK, htonl(ct->mark));
 280         return 0;
 281
 282 nla_put_failure:
 283         return -1;
 284 }
 285 #else
 286 #define ctnetlink_dump_mark(a, b) (0)
 287 #endif
 288
 289 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 290 static inline int
 291 ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
 292 {
 293         struct nlattr *nest_secctx;
 294         int len, ret;
 295         char *secctx;
 296
 297         ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
 298         if (ret)
 299                 return 0;
 300
 301         ret = -1;
 302         nest_secctx = nla_nest_start(skb, CTA_SECCTX | NLA_F_NESTED);
 303         if (!nest_secctx)
 304                 goto nla_put_failure;
 305
 306         NLA_PUT_STRING(skb, CTA_SECCTX_NAME, secctx);
 307         nla_nest_end(skb, nest_secctx);
 308
 309         ret = 0;
 310 nla_put_failure:
 311         security_release_secctx(secctx, len);
 312         return ret;
 313 }
 314 #else
 315 #define ctnetlink_dump_secctx(a, b) (0)
 316 #endif
 317
 318 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
 319
 320 static inline int
 321 ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
 322 {
 323         struct nlattr *nest_parms;
 324
 325         if (!(ct->status & IPS_EXPECTED))
 326                 return 0;
 327
 328         nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER | NLA_F_NESTED);
 329         if (!nest_parms)
 330                 goto nla_put_failure;
 331         if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
 332                 goto nla_put_failure;
 333         nla_nest_end(skb, nest_parms);
 334
 335         return 0;
 336
 337 nla_put_failure:
 338         return -1;
 339 }
 340
 341 #ifdef CONFIG_NF_NAT_NEEDED
 342 static int
 343 dump_nat_seq_adj(struct sk_buff *skb, const struct nf_nat_seq *natseq, int type)
 344 {
 345         struct nlattr *nest_parms;
 346
 347         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
 348         if (!nest_parms)
 349                 goto nla_put_failure;
 350
 351         NLA_PUT_BE32(skb, CTA_NAT_SEQ_CORRECTION_POS,
 352                      htonl(natseq->correction_pos));
 353         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_BEFORE,
 354                      htonl(natseq->offset_before));
 355         NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_AFTER,
 356                      htonl(natseq->offset_after));
 357
 358         nla_nest_end(skb, nest_parms);
 359
 360         return 0;
 361
 362 nla_put_failure:
 363         return -1;
 364 }
 365
 366 static inline int
 367 ctnetlink_dump_nat_seq_adj(struct sk_buff *skb, const struct nf_conn *ct)
 368 {
 369         struct nf_nat_seq *natseq;
 370         struct nf_conn_nat *nat = nfct_nat(ct);
 371
 372         if (!(ct->status & IPS_SEQ_ADJUST) || !nat)
 373                 return 0;
 374
 375         natseq = &nat->seq[IP_CT_DIR_ORIGINAL];
 376         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_ORIG) == -1)
 377                 return -1;
 378
 379         natseq = &nat->seq[IP_CT_DIR_REPLY];
 380         if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_REPLY) == -1)
 381                 return -1;
 382
 383         return 0;
 384 }
 385 #else
 386 #define ctnetlink_dump_nat_seq_adj(a, b) (0)
 387 #endif
 388
 389 static inline int
 390 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
 391 {
 392         NLA_PUT_BE32(skb, CTA_ID, htonl((unsigned long)ct));
 393         return 0;
 394
 395 nla_put_failure:
 396         return -1;
 397 }
 398
 399 static inline int
 400 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
 401 {
 402         NLA_PUT_BE32(skb, CTA_USE, htonl(atomic_read(&ct->ct_general.use)));
 403         return 0;
 404
 405 nla_put_failure:
 406         return -1;
 407 }
 408
 409 static int
 410 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq, u32 type,
 411                     struct nf_conn *ct)
 412 {
 413         struct nlmsghdr *nlh;
 414         struct nfgenmsg *nfmsg;
 415         struct nlattr *nest_parms;
 416         unsigned int flags = pid ? NLM_F_MULTI : 0, event;
 417
 418         event = (NFNL_SUBSYS_CTNETLINK << 8 | IPCTNL_MSG_CT_NEW);
 419         nlh = nlmsg_put(skb, pid, seq, event, sizeof(*nfmsg), flags);
 420         if (nlh == NULL)
 421                 goto nlmsg_failure;
 422
 423         nfmsg = nlmsg_data(nlh);
 424         nfmsg->nfgen_family = nf_ct_l3num(ct);
 425         nfmsg->version      = NFNETLINK_V0;
 426         nfmsg->res_id       = 0;
 427
 428         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
 429         if (!nest_parms)
 430                 goto nla_put_failure;
 431         if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 432                 goto nla_put_failure;
 433         nla_nest_end(skb, nest_parms);
 434
 435         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
 436         if (!nest_parms)
 437                 goto nla_put_failure;
 438         if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
 439                 goto nla_put_failure;
 440         nla_nest_end(skb, nest_parms);
 441
 442         if (nf_ct_zone(ct))
 443                 NLA_PUT_BE16(skb, CTA_ZONE, htons(nf_ct_zone(ct)));
 444
 445         if (ctnetlink_dump_status(skb, ct) < 0 ||
 446             ctnetlink_dump_timeout(skb, ct) < 0 ||
 447             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL, type) < 0 ||
 448             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY, type) < 0 ||
 449             ctnetlink_dump_timestamp(skb, ct) < 0 ||
 450             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
 451             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
 452             ctnetlink_dump_mark(skb, ct) < 0 ||
 453             ctnetlink_dump_secctx(skb, ct) < 0 ||
 454             ctnetlink_dump_id(skb, ct) < 0 ||
 455             ctnetlink_dump_use(skb, ct) < 0 ||
 456             ctnetlink_dump_master(skb, ct) < 0 ||
 457             ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
 458                 goto nla_put_failure;
 459
 460         nlmsg_end(skb, nlh);
 461         return skb->len;
 462
 463 nlmsg_failure:
 464 nla_put_failure:
 465         nlmsg_cancel(skb, nlh);
 466         return -1;
 467 }
 468
 469 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 470 static inline size_t
 471 ctnetlink_proto_size(const struct nf_conn *ct)
 472 {
 473         struct nf_conntrack_l3proto *l3proto;
 474         struct nf_conntrack_l4proto *l4proto;
 475         size_t len = 0;
 476
 477         rcu_read_lock();
 478         l3proto = __nf_ct_l3proto_find(nf_ct_l3num(ct));
 479         len += l3proto->nla_size;
 480
 481         l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
 482         len += l4proto->nla_size;
 483         rcu_read_unlock();
 484
 485         return len;
 486 }
 487
 488 static inline size_t
 489 ctnetlink_counters_size(const struct nf_conn *ct)
 490 {
 491         if (!nf_ct_ext_exist(ct, NF_CT_EXT_ACCT))
 492                 return 0;
 493         return 2 * nla_total_size(0) /* CTA_COUNTERS_ORIG|REPL */
 494                + 2 * nla_total_size(sizeof(uint64_t)) /* CTA_COUNTERS_PACKETS */
 495                + 2 * nla_total_size(sizeof(uint64_t)) /* CTA_COUNTERS_BYTES */
 496                ;
 497 }
 498
 499 static inline int
 500 ctnetlink_secctx_size(const struct nf_conn *ct)
 501 {
 502 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 503         int len, ret;
 504
 505         ret = security_secid_to_secctx(ct->secmark, NULL, &len);
 506         if (ret)
 507                 return 0;
 508
 509         return nla_total_size(0) /* CTA_SECCTX */
 510                + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
 511 #else
 512         return 0;
 513 #endif
 514 }
 515
 516 static inline size_t
 517 ctnetlink_timestamp_size(const struct nf_conn *ct)
 518 {
 519 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
 520         if (!nf_ct_ext_exist(ct, NF_CT_EXT_TSTAMP))
 521                 return 0;
 522         return nla_total_size(0) + 2 * nla_total_size(sizeof(uint64_t));
 523 #else
 524         return 0;
 525 #endif
 526 }
 527
 528 static inline size_t
 529 ctnetlink_nlmsg_size(const struct nf_conn *ct)
 530 {
 531         return NLMSG_ALIGN(sizeof(struct nfgenmsg))
 532                + 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
 533                + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
 534                + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
 535                + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
 536                + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
 537                + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
 538                + ctnetlink_counters_size(ct)
 539                + ctnetlink_timestamp_size(ct)
 540                + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
 541                + nla_total_size(0) /* CTA_PROTOINFO */
 542                + nla_total_size(0) /* CTA_HELP */
 543                + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
 544                + ctnetlink_secctx_size(ct)
 545 #ifdef CONFIG_NF_NAT_NEEDED
 546                + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
 547                + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
 548 #endif
 549 #ifdef CONFIG_NF_CONNTRACK_MARK
 550                + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
 551 #endif
 552                + ctnetlink_proto_size(ct)
 553                ;
 554 }
 555
 556 static int
 557 ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item)
 558 {
 559         struct net *net;
 560         struct nlmsghdr *nlh;
 561         struct nfgenmsg *nfmsg;
 562         struct nlattr *nest_parms;
 563         struct nf_conn *ct = item->ct;
 564         struct sk_buff *skb;
 565         unsigned int type;
 566         unsigned int flags = 0, group;
 567         int err;
 568
 569         /* ignore our fake conntrack entry */
 570         if (nf_ct_is_untracked(ct))
 571                 return 0;
 572
 573         if (events & (1 << IPCT_DESTROY)) {
 574                 type = IPCTNL_MSG_CT_DELETE;
 575                 group = NFNLGRP_CONNTRACK_DESTROY;
 576         } else  if (events & ((1 << IPCT_NEW) | (1 << IPCT_RELATED))) {
 577                 type = IPCTNL_MSG_CT_NEW;
 578                 flags = NLM_F_CREATE|NLM_F_EXCL;
 579                 group = NFNLGRP_CONNTRACK_NEW;
 580         } else  if (events) {
 581                 type = IPCTNL_MSG_CT_NEW;
 582                 group = NFNLGRP_CONNTRACK_UPDATE;
 583         } else
 584                 return 0;
 585
 586         net = nf_ct_net(ct);
 587         if (!item->report && !nfnetlink_has_listeners(net, group))
 588                 return 0;
 589
 590         skb = nlmsg_new(ctnetlink_nlmsg_size(ct), GFP_ATOMIC);
 591         if (skb == NULL)
 592                 goto errout;
 593
 594         type |= NFNL_SUBSYS_CTNETLINK << 8;
 595         nlh = nlmsg_put(skb, item->pid, 0, type, sizeof(*nfmsg), flags);
 596         if (nlh == NULL)
 597                 goto nlmsg_failure;
 598
 599         nfmsg = nlmsg_data(nlh);
 600         nfmsg->nfgen_family = nf_ct_l3num(ct);
 601         nfmsg->version  = NFNETLINK_V0;
 602         nfmsg->res_id   = 0;
 603
 604         rcu_read_lock();
 605         nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
 606         if (!nest_parms)
 607                 goto nla_put_failure;
 608         if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
 609                 goto nla_put_failure;
 610         nla_nest_end(skb, nest_parms);
 611
 612         nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
 613         if (!nest_parms)
 614                 goto nla_put_failure;
 615         if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
 616                 goto nla_put_failure;
 617         nla_nest_end(skb, nest_parms);
 618
 619         if (nf_ct_zone(ct))
 620                 NLA_PUT_BE16(skb, CTA_ZONE, htons(nf_ct_zone(ct)));
 621
 622         if (ctnetlink_dump_id(skb, ct) < 0)
 623                 goto nla_put_failure;
 624
 625         if (ctnetlink_dump_status(skb, ct) < 0)
 626                 goto nla_put_failure;
 627
 628         if (events & (1 << IPCT_DESTROY)) {
 629                 if (ctnetlink_dump_counters(skb, ct,
 630                                             IP_CT_DIR_ORIGINAL, type) < 0 ||
 631                     ctnetlink_dump_counters(skb, ct,
 632                                             IP_CT_DIR_REPLY, type) < 0 ||
 633                     ctnetlink_dump_timestamp(skb, ct) < 0)
 634                         goto nla_put_failure;
 635         } else {
 636                 if (ctnetlink_dump_timeout(skb, ct) < 0)
 637                         goto nla_put_failure;
 638
 639                 if (events & (1 << IPCT_PROTOINFO)
 640                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
 641                         goto nla_put_failure;
 642
 643                 if ((events & (1 << IPCT_HELPER) || nfct_help(ct))
 644                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
 645                         goto nla_put_failure;
 646
 647 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 648                 if ((events & (1 << IPCT_SECMARK) || ct->secmark)
 649                     && ctnetlink_dump_secctx(skb, ct) < 0)
 650                         goto nla_put_failure;
 651 #endif
 652
 653                 if (events & (1 << IPCT_RELATED) &&
 654                     ctnetlink_dump_master(skb, ct) < 0)
 655                         goto nla_put_failure;
 656
 657                 if (events & (1 << IPCT_NATSEQADJ) &&
 658                     ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
 659                         goto nla_put_failure;
 660         }
 661
 662 #ifdef CONFIG_NF_CONNTRACK_MARK
 663         if ((events & (1 << IPCT_MARK) || ct->mark)
 664             && ctnetlink_dump_mark(skb, ct) < 0)
 665                 goto nla_put_failure;
 666 #endif
 667         rcu_read_unlock();
 668
 669         nlmsg_end(skb, nlh);
 670         err = nfnetlink_send(skb, net, item->pid, group, item->report,
 671                              GFP_ATOMIC);
 672         if (err == -ENOBUFS || err == -EAGAIN)
 673                 return -ENOBUFS;
 674
 675         return 0;
 676
 677 nla_put_failure:
 678         rcu_read_unlock();
 679         nlmsg_cancel(skb, nlh);
 680 nlmsg_failure:
 681         kfree_skb(skb);
 682 errout:
 683         if (nfnetlink_set_err(net, 0, group, -ENOBUFS) > 0)
 684                 return -ENOBUFS;
 685
 686         return 0;
 687 }
 688 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 689
 690 static int ctnetlink_done(struct netlink_callback *cb)
 691 {
 692         if (cb->args[1])
 693                 nf_ct_put((struct nf_conn *)cb->args[1]);
 694         return 0;
 695 }
 696
 697 static int
 698 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
 699 {
 700         struct net *net = sock_net(skb->sk);
 701         struct nf_conn *ct, *last;
 702         struct nf_conntrack_tuple_hash *h;
 703         struct hlist_nulls_node *n;
 704         struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
 705         u_int8_t l3proto = nfmsg->nfgen_family;
 706
 707         spin_lock_bh(&nf_conntrack_lock);
 708         last = (struct nf_conn *)cb->args[1];
 709         for (; cb->args[0] < net->ct.htable_size; cb->args[0]++) {
 710 restart:
 711                 hlist_nulls_for_each_entry(h, n, &net->ct.hash[cb->args[0]],
 712                                          hnnode) {
 713                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
 714                                 continue;
 715                         ct = nf_ct_tuplehash_to_ctrack(h);
 716                         /* Dump entries of a given L3 protocol number.
 717                          * If it is not specified, ie. l3proto == 0,
 718                          * then dump everything. */
 719                         if (l3proto && nf_ct_l3num(ct) != l3proto)
 720                                 continue;
 721                         if (cb->args[1]) {
 722                                 if (ct != last)
 723                                         continue;
 724                                 cb->args[1] = 0;
 725                         }
 726                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
 727                                                 cb->nlh->nlmsg_seq,
 728                                                 NFNL_MSG_TYPE(
 729                                                         cb->nlh->nlmsg_type),
 730                                                 ct) < 0) {
 731                                 nf_conntrack_get(&ct->ct_general);
 732                                 cb->args[1] = (unsigned long)ct;
 733                                 goto out;
 734                         }
 735                 }
 736                 if (cb->args[1]) {
 737                         cb->args[1] = 0;
 738                         goto restart;
 739                 }
 740         }
 741 out:
 742         spin_unlock_bh(&nf_conntrack_lock);
 743         if (last)
 744                 nf_ct_put(last);
 745
 746         return skb->len;
 747 }
 748
 749 static inline int
 750 ctnetlink_parse_tuple_ip(struct nlattr *attr, struct nf_conntrack_tuple *tuple)
 751 {
 752         struct nlattr *tb[CTA_IP_MAX+1];
 753         struct nf_conntrack_l3proto *l3proto;
 754         int ret = 0;
 755
 756         nla_parse_nested(tb, CTA_IP_MAX, attr, NULL);
 757
 758         rcu_read_lock();
 759         l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
 760
 761         if (likely(l3proto->nlattr_to_tuple)) {
 762                 ret = nla_validate_nested(attr, CTA_IP_MAX,
 763                                           l3proto->nla_policy);
 764                 if (ret == 0)
 765                         ret = l3proto->nlattr_to_tuple(tb, tuple);
 766         }
 767
 768         rcu_read_unlock();
 769
 770         return ret;
 771 }
 772
 773 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
 774         [CTA_PROTO_NUM] = { .type = NLA_U8 },
 775 };
 776
 777 static inline int
 778 ctnetlink_parse_tuple_proto(struct nlattr *attr,
 779                             struct nf_conntrack_tuple *tuple)
 780 {
 781         struct nlattr *tb[CTA_PROTO_MAX+1];
 782         struct nf_conntrack_l4proto *l4proto;
 783         int ret = 0;
 784
 785         ret = nla_parse_nested(tb, CTA_PROTO_MAX, attr, proto_nla_policy);
 786         if (ret < 0)
 787                 return ret;
 788
 789         if (!tb[CTA_PROTO_NUM])
 790                 return -EINVAL;
 791         tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
 792
 793         rcu_read_lock();
 794         l4proto = __nf_ct_l4proto_find(tuple->src.l3num, tuple->dst.protonum);
 795
 796         if (likely(l4proto->nlattr_to_tuple)) {
 797                 ret = nla_validate_nested(attr, CTA_PROTO_MAX,
 798                                           l4proto->nla_policy);
 799                 if (ret == 0)
 800                         ret = l4proto->nlattr_to_tuple(tb, tuple);
 801         }
 802
 803         rcu_read_unlock();
 804
 805         return ret;
 806 }
 807
 808 static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = {
 809         [CTA_TUPLE_IP]          = { .type = NLA_NESTED },
 810         [CTA_TUPLE_PROTO]       = { .type = NLA_NESTED },
 811 };
 812
 813 static int
 814 ctnetlink_parse_tuple(const struct nlattr * const cda[],
 815                       struct nf_conntrack_tuple *tuple,
 816                       enum ctattr_type type, u_int8_t l3num)
 817 {
 818         struct nlattr *tb[CTA_TUPLE_MAX+1];
 819         int err;
 820
 821         memset(tuple, 0, sizeof(*tuple));
 822
 823         nla_parse_nested(tb, CTA_TUPLE_MAX, cda[type], tuple_nla_policy);
 824
 825         if (!tb[CTA_TUPLE_IP])
 826                 return -EINVAL;
 827
 828         tuple->src.l3num = l3num;
 829
 830         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple);
 831         if (err < 0)
 832                 return err;
 833
 834         if (!tb[CTA_TUPLE_PROTO])
 835                 return -EINVAL;
 836
 837         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple);
 838         if (err < 0)
 839                 return err;
 840
 841         /* orig and expect tuples get DIR_ORIGINAL */
 842         if (type == CTA_TUPLE_REPLY)
 843                 tuple->dst.dir = IP_CT_DIR_REPLY;
 844         else
 845                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
 846
 847         return 0;
 848 }
 849
 850 static int
 851 ctnetlink_parse_zone(const struct nlattr *attr, u16 *zone)
 852 {
 853         if (attr)
 854 #ifdef CONFIG_NF_CONNTRACK_ZONES
 855                 *zone = ntohs(nla_get_be16(attr));
 856 #else
 857                 return -EOPNOTSUPP;
 858 #endif
 859         else
 860                 *zone = 0;
 861
 862         return 0;
 863 }
 864
 865 static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
 866         [CTA_HELP_NAME]         = { .type = NLA_NUL_STRING },
 867 };
 868
 869 static inline int
 870 ctnetlink_parse_help(const struct nlattr *attr, char **helper_name)
 871 {
 872         struct nlattr *tb[CTA_HELP_MAX+1];
 873
 874         nla_parse_nested(tb, CTA_HELP_MAX, attr, help_nla_policy);
 875
 876         if (!tb[CTA_HELP_NAME])
 877                 return -EINVAL;
 878
 879         *helper_name = nla_data(tb[CTA_HELP_NAME]);
 880
 881         return 0;
 882 }
 883
 884 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
 885         [CTA_TUPLE_ORIG]        = { .type = NLA_NESTED },
 886         [CTA_TUPLE_REPLY]       = { .type = NLA_NESTED },
 887         [CTA_STATUS]            = { .type = NLA_U32 },
 888         [CTA_PROTOINFO]         = { .type = NLA_NESTED },
 889         [CTA_HELP]              = { .type = NLA_NESTED },
 890         [CTA_NAT_SRC]           = { .type = NLA_NESTED },
 891         [CTA_TIMEOUT]           = { .type = NLA_U32 },
 892         [CTA_MARK]              = { .type = NLA_U32 },
 893         [CTA_ID]                = { .type = NLA_U32 },
 894         [CTA_NAT_DST]           = { .type = NLA_NESTED },
 895         [CTA_TUPLE_MASTER]      = { .type = NLA_NESTED },
 896         [CTA_ZONE]              = { .type = NLA_U16 },
 897 };
 898
 899 static int
 900 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
 901                         const struct nlmsghdr *nlh,
 902                         const struct nlattr * const cda[])
 903 {
 904         struct net *net = sock_net(ctnl);
 905         struct nf_conntrack_tuple_hash *h;
 906         struct nf_conntrack_tuple tuple;
 907         struct nf_conn *ct;
 908         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
 909         u_int8_t u3 = nfmsg->nfgen_family;
 910         u16 zone;
 911         int err;
 912
 913         err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
 914         if (err < 0)
 915                 return err;
 916
 917         if (cda[CTA_TUPLE_ORIG])
 918                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 919         else if (cda[CTA_TUPLE_REPLY])
 920                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 921         else {
 922                 /* Flush the whole table */
 923                 nf_conntrack_flush_report(net,
 924                                          NETLINK_CB(skb).pid,
 925                                          nlmsg_report(nlh));
 926                 return 0;
 927         }
 928
 929         if (err < 0)
 930                 return err;
 931
 932         h = nf_conntrack_find_get(net, zone, &tuple);
 933         if (!h)
 934                 return -ENOENT;
 935
 936         ct = nf_ct_tuplehash_to_ctrack(h);
 937
 938         if (cda[CTA_ID]) {
 939                 u_int32_t id = ntohl(nla_get_be32(cda[CTA_ID]));
 940                 if (id != (u32)(unsigned long)ct) {
 941                         nf_ct_put(ct);
 942                         return -ENOENT;
 943                 }
 944         }
 945
 946         if (nf_conntrack_event_report(IPCT_DESTROY, ct,
 947                                       NETLINK_CB(skb).pid,
 948                                       nlmsg_report(nlh)) < 0) {
 949                 nf_ct_delete_from_lists(ct);
 950                 /* we failed to report the event, try later */
 951                 nf_ct_insert_dying_list(ct);
 952                 nf_ct_put(ct);
 953                 return 0;
 954         }
 955
 956         /* death_by_timeout would report the event again */
 957         set_bit(IPS_DYING_BIT, &ct->status);
 958
 959         nf_ct_kill(ct);
 960         nf_ct_put(ct);
 961
 962         return 0;
 963 }
 964
 965 static int
 966 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 967                         const struct nlmsghdr *nlh,
 968                         const struct nlattr * const cda[])
 969 {
 970         struct net *net = sock_net(ctnl);
 971         struct nf_conntrack_tuple_hash *h;
 972         struct nf_conntrack_tuple tuple;
 973         struct nf_conn *ct;
 974         struct sk_buff *skb2 = NULL;
 975         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
 976         u_int8_t u3 = nfmsg->nfgen_family;
 977         u16 zone;
 978         int err;
 979
 980         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 981                 struct netlink_dump_control c = {
 982                         .dump = ctnetlink_dump_table,
 983                         .done = ctnetlink_done,
 984                 };
 985                 return netlink_dump_start(ctnl, skb, nlh, &c);
 986         }
 987
 988         err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
 989         if (err < 0)
 990                 return err;
 991
 992         if (cda[CTA_TUPLE_ORIG])
 993                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
 994         else if (cda[CTA_TUPLE_REPLY])
 995                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
 996         else
 997                 return -EINVAL;
 998
 999         if (err < 0)
1000                 return err;
1001
1002         h = nf_conntrack_find_get(net, zone, &tuple);
1003         if (!h)
1004                 return -ENOENT;
1005
1006         ct = nf_ct_tuplehash_to_ctrack(h);
1007
1008         err = -ENOMEM;
1009         skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1010         if (skb2 == NULL) {
1011                 nf_ct_put(ct);
1012                 return -ENOMEM;
1013         }
1014
1015         rcu_read_lock();
1016         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
1017                                   NFNL_MSG_TYPE(nlh->nlmsg_type), ct);
1018         rcu_read_unlock();
1019         nf_ct_put(ct);
1020         if (err <= 0)
1021                 goto free;
1022
1023         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1024         if (err < 0)
1025                 goto out;
1026
1027         return 0;
1028
1029 free:
1030         kfree_skb(skb2);
1031 out:
1032         /* this avoids a loop in nfnetlink. */
1033         return err == -EAGAIN ? -ENOBUFS : err;
1034 }
1035
1036 #ifdef CONFIG_NF_NAT_NEEDED
1037 static int
1038 ctnetlink_parse_nat_setup(struct nf_conn *ct,
1039                           enum nf_nat_manip_type manip,
1040                           const struct nlattr *attr)
1041 {
1042         typeof(nfnetlink_parse_nat_setup_hook) parse_nat_setup;
1043
1044         parse_nat_setup = rcu_dereference(nfnetlink_parse_nat_setup_hook);
1045         if (!parse_nat_setup) {
1046 #ifdef CONFIG_MODULES
1047                 rcu_read_unlock();
1048                 spin_unlock_bh(&nf_conntrack_lock);
1049                 nfnl_unlock();
1050                 if (request_module("nf-nat-ipv4") < 0) {
1051                         nfnl_lock();
1052                         spin_lock_bh(&nf_conntrack_lock);
1053                         rcu_read_lock();
1054                         return -EOPNOTSUPP;
1055                 }
1056                 nfnl_lock();
1057                 spin_lock_bh(&nf_conntrack_lock);
1058                 rcu_read_lock();
1059                 if (nfnetlink_parse_nat_setup_hook)
1060                         return -EAGAIN;
1061 #endif
1062                 return -EOPNOTSUPP;
1063         }
1064
1065         return parse_nat_setup(ct, manip, attr);
1066 }
1067 #endif
1068
1069 static int
1070 ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[])
1071 {
1072         unsigned long d;
1073         unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
1074         d = ct->status ^ status;
1075
1076         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
1077                 /* unchangeable */
1078                 return -EBUSY;
1079
1080         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
1081                 /* SEEN_REPLY bit can only be set */
1082                 return -EBUSY;
1083
1084         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
1085                 /* ASSURED bit can only be set */
1086                 return -EBUSY;
1087
1088         /* Be careful here, modifying NAT bits can screw up things,
1089          * so don't let users modify them directly if they don't pass
1090          * nf_nat_range. */
1091         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
1092         return 0;
1093 }
1094
1095 static int
1096 ctnetlink_change_nat(struct nf_conn *ct, const struct nlattr * const cda[])
1097 {
1098 #ifdef CONFIG_NF_NAT_NEEDED
1099         int ret;
1100
1101         if (cda[CTA_NAT_DST]) {
1102                 ret = ctnetlink_parse_nat_setup(ct,
1103                                                 NF_NAT_MANIP_DST,
1104                                                 cda[CTA_NAT_DST]);
1105                 if (ret < 0)
1106                         return ret;
1107         }
1108         if (cda[CTA_NAT_SRC]) {
1109                 ret = ctnetlink_parse_nat_setup(ct,
1110                                                 NF_NAT_MANIP_SRC,
1111                                                 cda[CTA_NAT_SRC]);
1112                 if (ret < 0)
1113                         return ret;
1114         }
1115         return 0;
1116 #else
1117         return -EOPNOTSUPP;
1118 #endif
1119 }
1120
1121 static inline int
1122 ctnetlink_change_helper(struct nf_conn *ct, const struct nlattr * const cda[])
1123 {
1124         struct nf_conntrack_helper *helper;
1125         struct nf_conn_help *help = nfct_help(ct);
1126         char *helpname = NULL;
1127         int err;
1128
1129         /* don't change helper of sibling connections */
1130         if (ct->master)
1131                 return -EBUSY;
1132
1133         err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
1134         if (err < 0)
1135                 return err;
1136
1137         if (!strcmp(helpname, "")) {
1138                 if (help && help->helper) {
1139                         /* we had a helper before ... */
1140                         nf_ct_remove_expectations(ct);
1141                         RCU_INIT_POINTER(help->helper, NULL);
1142                 }
1143
1144                 return 0;
1145         }
1146
1147         helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1148                                             nf_ct_protonum(ct));
1149         if (helper == NULL) {
1150 #ifdef CONFIG_MODULES
1151                 spin_unlock_bh(&nf_conntrack_lock);
1152
1153                 if (request_module("nfct-helper-%s", helpname) < 0) {
1154                         spin_lock_bh(&nf_conntrack_lock);
1155                         return -EOPNOTSUPP;
1156                 }
1157
1158                 spin_lock_bh(&nf_conntrack_lock);
1159                 helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1160                                                     nf_ct_protonum(ct));
1161                 if (helper)
1162                         return -EAGAIN;
1163 #endif
1164                 return -EOPNOTSUPP;
1165         }
1166
1167         if (help) {
1168                 if (help->helper == helper)
1169                         return 0;
1170                 if (help->helper)
1171                         return -EBUSY;
1172                 /* need to zero data of old helper */
1173                 memset(&help->help, 0, sizeof(help->help));
1174         } else {
1175                 /* we cannot set a helper for an existing conntrack */
1176                 return -EOPNOTSUPP;
1177         }
1178
1179         rcu_assign_pointer(help->helper, helper);
1180
1181         return 0;
1182 }
1183
1184 static inline int
1185 ctnetlink_change_timeout(struct nf_conn *ct, const struct nlattr * const cda[])
1186 {
1187         u_int32_t timeout = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
1188
1189         if (!del_timer(&ct->timeout))
1190                 return -ETIME;
1191
1192         ct->timeout.expires = jiffies + timeout * HZ;
1193         add_timer(&ct->timeout);
1194
1195         return 0;
1196 }
1197
1198 static const struct nla_policy protoinfo_policy[CTA_PROTOINFO_MAX+1] = {
1199         [CTA_PROTOINFO_TCP]     = { .type = NLA_NESTED },
1200         [CTA_PROTOINFO_DCCP]    = { .type = NLA_NESTED },
1201         [CTA_PROTOINFO_SCTP]    = { .type = NLA_NESTED },
1202 };
1203
1204 static inline int
1205 ctnetlink_change_protoinfo(struct nf_conn *ct, const struct nlattr * const cda[])
1206 {
1207         const struct nlattr *attr = cda[CTA_PROTOINFO];
1208         struct nlattr *tb[CTA_PROTOINFO_MAX+1];
1209         struct nf_conntrack_l4proto *l4proto;
1210         int err = 0;
1211
1212         nla_parse_nested(tb, CTA_PROTOINFO_MAX, attr, protoinfo_policy);
1213
1214         rcu_read_lock();
1215         l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
1216         if (l4proto->from_nlattr)
1217                 err = l4proto->from_nlattr(tb, ct);
1218         rcu_read_unlock();
1219
1220         return err;
1221 }
1222
1223 #ifdef CONFIG_NF_NAT_NEEDED
1224 static const struct nla_policy nat_seq_policy[CTA_NAT_SEQ_MAX+1] = {
1225         [CTA_NAT_SEQ_CORRECTION_POS]    = { .type = NLA_U32 },
1226         [CTA_NAT_SEQ_OFFSET_BEFORE]     = { .type = NLA_U32 },
1227         [CTA_NAT_SEQ_OFFSET_AFTER]      = { .type = NLA_U32 },
1228 };
1229
1230 static inline int
1231 change_nat_seq_adj(struct nf_nat_seq *natseq, const struct nlattr * const attr)
1232 {
1233         struct nlattr *cda[CTA_NAT_SEQ_MAX+1];
1234
1235         nla_parse_nested(cda, CTA_NAT_SEQ_MAX, attr, nat_seq_policy);
1236
1237         if (!cda[CTA_NAT_SEQ_CORRECTION_POS])
1238                 return -EINVAL;
1239
1240         natseq->correction_pos =
1241                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_CORRECTION_POS]));
1242
1243         if (!cda[CTA_NAT_SEQ_OFFSET_BEFORE])
1244                 return -EINVAL;
1245
1246         natseq->offset_before =
1247                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_BEFORE]));
1248
1249         if (!cda[CTA_NAT_SEQ_OFFSET_AFTER])
1250                 return -EINVAL;
1251
1252         natseq->offset_after =
1253                 ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_AFTER]));
1254
1255         return 0;
1256 }
1257
1258 static int
1259 ctnetlink_change_nat_seq_adj(struct nf_conn *ct,
1260                              const struct nlattr * const cda[])
1261 {
1262         int ret = 0;
1263         struct nf_conn_nat *nat = nfct_nat(ct);
1264
1265         if (!nat)
1266                 return 0;
1267
1268         if (cda[CTA_NAT_SEQ_ADJ_ORIG]) {
1269                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_ORIGINAL],
1270                                          cda[CTA_NAT_SEQ_ADJ_ORIG]);
1271                 if (ret < 0)
1272                         return ret;
1273
1274                 ct->status |= IPS_SEQ_ADJUST;
1275         }
1276
1277         if (cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1278                 ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_REPLY],
1279                                          cda[CTA_NAT_SEQ_ADJ_REPLY]);
1280                 if (ret < 0)
1281                         return ret;
1282
1283                 ct->status |= IPS_SEQ_ADJUST;
1284         }
1285
1286         return 0;
1287 }
1288 #endif
1289
1290 static int
1291 ctnetlink_change_conntrack(struct nf_conn *ct,
1292                            const struct nlattr * const cda[])
1293 {
1294         int err;
1295
1296         /* only allow NAT changes and master assignation for new conntracks */
1297         if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST] || cda[CTA_TUPLE_MASTER])
1298                 return -EOPNOTSUPP;
1299
1300         if (cda[CTA_HELP]) {
1301                 err = ctnetlink_change_helper(ct, cda);
1302                 if (err < 0)
1303                         return err;
1304         }
1305
1306         if (cda[CTA_TIMEOUT]) {
1307                 err = ctnetlink_change_timeout(ct, cda);
1308                 if (err < 0)
1309                         return err;
1310         }
1311
1312         if (cda[CTA_STATUS]) {
1313                 err = ctnetlink_change_status(ct, cda);
1314                 if (err < 0)
1315                         return err;
1316         }
1317
1318         if (cda[CTA_PROTOINFO]) {
1319                 err = ctnetlink_change_protoinfo(ct, cda);
1320                 if (err < 0)
1321                         return err;
1322         }
1323
1324 #if defined(CONFIG_NF_CONNTRACK_MARK)
1325         if (cda[CTA_MARK])
1326                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1327 #endif
1328
1329 #ifdef CONFIG_NF_NAT_NEEDED
1330         if (cda[CTA_NAT_SEQ_ADJ_ORIG] || cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1331                 err = ctnetlink_change_nat_seq_adj(ct, cda);
1332                 if (err < 0)
1333                         return err;
1334         }
1335 #endif
1336
1337         return 0;
1338 }
1339
1340 static struct nf_conn *
1341 ctnetlink_create_conntrack(struct net *net, u16 zone,
1342                            const struct nlattr * const cda[],
1343                            struct nf_conntrack_tuple *otuple,
1344                            struct nf_conntrack_tuple *rtuple,
1345                            u8 u3)
1346 {
1347         struct nf_conn *ct;
1348         int err = -EINVAL;
1349         struct nf_conntrack_helper *helper;
1350         struct nf_conn_tstamp *tstamp;
1351
1352         ct = nf_conntrack_alloc(net, zone, otuple, rtuple, GFP_ATOMIC);
1353         if (IS_ERR(ct))
1354                 return ERR_PTR(-ENOMEM);
1355
1356         if (!cda[CTA_TIMEOUT])
1357                 goto err1;
1358         ct->timeout.expires = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
1359
1360         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
1361
1362         rcu_read_lock();
1363         if (cda[CTA_HELP]) {
1364                 char *helpname = NULL;
1365
1366                 err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
1367                 if (err < 0)
1368                         goto err2;
1369
1370                 helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1371                                                     nf_ct_protonum(ct));
1372                 if (helper == NULL) {
1373                         rcu_read_unlock();
1374                         spin_unlock_bh(&nf_conntrack_lock);
1375 #ifdef CONFIG_MODULES
1376                         if (request_module("nfct-helper-%s", helpname) < 0) {
1377                                 spin_lock_bh(&nf_conntrack_lock);
1378                                 err = -EOPNOTSUPP;
1379                                 goto err1;
1380                         }
1381
1382                         spin_lock_bh(&nf_conntrack_lock);
1383                         rcu_read_lock();
1384                         helper = __nf_conntrack_helper_find(helpname,
1385                                                             nf_ct_l3num(ct),
1386                                                             nf_ct_protonum(ct));
1387                         if (helper) {
1388                                 err = -EAGAIN;
1389                                 goto err2;
1390                         }
1391                         rcu_read_unlock();
1392 #endif
1393                         err = -EOPNOTSUPP;
1394                         goto err1;
1395                 } else {
1396                         struct nf_conn_help *help;
1397
1398                         help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
1399                         if (help == NULL) {
1400                                 err = -ENOMEM;
1401                                 goto err2;
1402                         }
1403
1404                         /* not in hash table yet so not strictly necessary */
1405                         RCU_INIT_POINTER(help->helper, helper);
1406                 }
1407         } else {
1408                 /* try an implicit helper assignation */
1409                 err = __nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC);
1410                 if (err < 0)
1411                         goto err2;
1412         }
1413
1414         if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
1415                 err = ctnetlink_change_nat(ct, cda);
1416                 if (err < 0)
1417                         goto err2;
1418         }
1419
1420         nf_ct_acct_ext_add(ct, GFP_ATOMIC);
1421         nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
1422         nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC);
1423         /* we must add conntrack extensions before confirmation. */
1424         ct->status |= IPS_CONFIRMED;
1425
1426         if (cda[CTA_STATUS]) {
1427                 err = ctnetlink_change_status(ct, cda);
1428                 if (err < 0)
1429                         goto err2;
1430         }
1431
1432 #ifdef CONFIG_NF_NAT_NEEDED
1433         if (cda[CTA_NAT_SEQ_ADJ_ORIG] || cda[CTA_NAT_SEQ_ADJ_REPLY]) {
1434                 err = ctnetlink_change_nat_seq_adj(ct, cda);
1435                 if (err < 0)
1436                         goto err2;
1437         }
1438 #endif
1439
1440         memset(&ct->proto, 0, sizeof(ct->proto));
1441         if (cda[CTA_PROTOINFO]) {
1442                 err = ctnetlink_change_protoinfo(ct, cda);
1443                 if (err < 0)
1444                         goto err2;
1445         }
1446
1447 #if defined(CONFIG_NF_CONNTRACK_MARK)
1448         if (cda[CTA_MARK])
1449                 ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1450 #endif
1451
1452         /* setup master conntrack: this is a confirmed expectation */
1453         if (cda[CTA_TUPLE_MASTER]) {
1454                 struct nf_conntrack_tuple master;
1455                 struct nf_conntrack_tuple_hash *master_h;
1456                 struct nf_conn *master_ct;
1457
1458                 err = ctnetlink_parse_tuple(cda, &master, CTA_TUPLE_MASTER, u3);
1459                 if (err < 0)
1460                         goto err2;
1461
1462                 master_h = nf_conntrack_find_get(net, zone, &master);
1463                 if (master_h == NULL) {
1464                         err = -ENOENT;
1465                         goto err2;
1466                 }
1467                 master_ct = nf_ct_tuplehash_to_ctrack(master_h);
1468                 __set_bit(IPS_EXPECTED_BIT, &ct->status);
1469                 ct->master = master_ct;
1470         }
1471         tstamp = nf_conn_tstamp_find(ct);
1472         if (tstamp)
1473                 tstamp->start = ktime_to_ns(ktime_get_real());
1474
1475         add_timer(&ct->timeout);
1476         nf_conntrack_hash_insert(ct);
1477         rcu_read_unlock();
1478
1479         return ct;
1480
1481 err2:
1482         rcu_read_unlock();
1483 err1:
1484         nf_conntrack_free(ct);
1485         return ERR_PTR(err);
1486 }
1487
1488 static int
1489 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1490                         const struct nlmsghdr *nlh,
1491                         const struct nlattr * const cda[])
1492 {
1493         struct net *net = sock_net(ctnl);
1494         struct nf_conntrack_tuple otuple, rtuple;
1495         struct nf_conntrack_tuple_hash *h = NULL;
1496         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1497         u_int8_t u3 = nfmsg->nfgen_family;
1498         u16 zone;
1499         int err;
1500
1501         err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1502         if (err < 0)
1503                 return err;
1504
1505         if (cda[CTA_TUPLE_ORIG]) {
1506                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1507                 if (err < 0)
1508                         return err;
1509         }
1510
1511         if (cda[CTA_TUPLE_REPLY]) {
1512                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1513                 if (err < 0)
1514                         return err;
1515         }
1516
1517         spin_lock_bh(&nf_conntrack_lock);
1518         if (cda[CTA_TUPLE_ORIG])
1519                 h = __nf_conntrack_find(net, zone, &otuple);
1520         else if (cda[CTA_TUPLE_REPLY])
1521                 h = __nf_conntrack_find(net, zone, &rtuple);
1522
1523         if (h == NULL) {
1524                 err = -ENOENT;
1525                 if (nlh->nlmsg_flags & NLM_F_CREATE) {
1526                         struct nf_conn *ct;
1527                         enum ip_conntrack_events events;
1528
1529                         ct = ctnetlink_create_conntrack(net, zone, cda, &otuple,
1530                                                         &rtuple, u3);
1531                         if (IS_ERR(ct)) {
1532                                 err = PTR_ERR(ct);
1533                                 goto out_unlock;
1534                         }
1535                         err = 0;
1536                         nf_conntrack_get(&ct->ct_general);
1537                         spin_unlock_bh(&nf_conntrack_lock);
1538                         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1539                                 events = IPCT_RELATED;
1540                         else
1541                                 events = IPCT_NEW;
1542
1543                         nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
1544                                                       (1 << IPCT_ASSURED) |
1545                                                       (1 << IPCT_HELPER) |
1546                                                       (1 << IPCT_PROTOINFO) |
1547                                                       (1 << IPCT_NATSEQADJ) |
1548                                                       (1 << IPCT_MARK) | events,
1549                                                       ct, NETLINK_CB(skb).pid,
1550                                                       nlmsg_report(nlh));
1551                         nf_ct_put(ct);
1552                 } else
1553                         spin_unlock_bh(&nf_conntrack_lock);
1554
1555                 return err;
1556         }
1557         /* implicit 'else' */
1558
1559         /* We manipulate the conntrack inside the global conntrack table lock,
1560          * so there's no need to increase the refcount */
1561         err = -EEXIST;
1562         if (!(nlh->nlmsg_flags & NLM_F_EXCL)) {
1563                 struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
1564
1565                 err = ctnetlink_change_conntrack(ct, cda);
1566                 if (err == 0) {
1567                         nf_conntrack_get(&ct->ct_general);
1568                         spin_unlock_bh(&nf_conntrack_lock);
1569                         nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
1570                                                       (1 << IPCT_ASSURED) |
1571                                                       (1 << IPCT_HELPER) |
1572                                                       (1 << IPCT_PROTOINFO) |
1573                                                       (1 << IPCT_NATSEQADJ) |
1574                                                       (1 << IPCT_MARK),
1575                                                       ct, NETLINK_CB(skb).pid,
1576                                                       nlmsg_report(nlh));
1577                         nf_ct_put(ct);
1578                 } else
1579                         spin_unlock_bh(&nf_conntrack_lock);
1580
1581                 return err;
1582         }
1583
1584 out_unlock:
1585         spin_unlock_bh(&nf_conntrack_lock);
1586         return err;
1587 }
1588
1589 /***********************************************************************
1590  * EXPECT
1591  ***********************************************************************/
1592
1593 static inline int
1594 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1595                          const struct nf_conntrack_tuple *tuple,
1596                          enum ctattr_expect type)
1597 {
1598         struct nlattr *nest_parms;
1599
1600         nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
1601         if (!nest_parms)
1602                 goto nla_put_failure;
1603         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1604                 goto nla_put_failure;
1605         nla_nest_end(skb, nest_parms);
1606
1607         return 0;
1608
1609 nla_put_failure:
1610         return -1;
1611 }
1612
1613 static inline int
1614 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1615                         const struct nf_conntrack_tuple *tuple,
1616                         const struct nf_conntrack_tuple_mask *mask)
1617 {
1618         int ret;
1619         struct nf_conntrack_l3proto *l3proto;
1620         struct nf_conntrack_l4proto *l4proto;
1621         struct nf_conntrack_tuple m;
1622         struct nlattr *nest_parms;
1623
1624         memset(&m, 0xFF, sizeof(m));
1625         memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
1626         m.src.u.all = mask->src.u.all;
1627         m.dst.protonum = tuple->dst.protonum;
1628
1629         nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK | NLA_F_NESTED);
1630         if (!nest_parms)
1631                 goto nla_put_failure;
1632
1633         l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
1634         ret = ctnetlink_dump_tuples_ip(skb, &m, l3proto);
1635
1636         if (unlikely(ret < 0))
1637                 goto nla_put_failure;
1638
1639         l4proto = __nf_ct_l4proto_find(tuple->src.l3num, tuple->dst.protonum);
1640         ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
1641         if (unlikely(ret < 0))
1642                 goto nla_put_failure;
1643
1644         nla_nest_end(skb, nest_parms);
1645
1646         return 0;
1647
1648 nla_put_failure:
1649         return -1;
1650 }
1651
1652 static int
1653 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1654                           const struct nf_conntrack_expect *exp)
1655 {
1656         struct nf_conn *master = exp->master;
1657         long timeout = ((long)exp->timeout.expires - (long)jiffies) / HZ;
1658         struct nf_conn_help *help;
1659
1660         if (timeout < 0)
1661                 timeout = 0;
1662
1663         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1664                 goto nla_put_failure;
1665         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1666                 goto nla_put_failure;
1667         if (ctnetlink_exp_dump_tuple(skb,
1668                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1669                                  CTA_EXPECT_MASTER) < 0)
1670                 goto nla_put_failure;
1671
1672         NLA_PUT_BE32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout));
1673         NLA_PUT_BE32(skb, CTA_EXPECT_ID, htonl((unsigned long)exp));
1674         NLA_PUT_BE32(skb, CTA_EXPECT_FLAGS, htonl(exp->flags));
1675         help = nfct_help(master);
1676         if (help) {
1677                 struct nf_conntrack_helper *helper;
1678
1679                 helper = rcu_dereference(help->helper);
1680                 if (helper)
1681                         NLA_PUT_STRING(skb, CTA_EXPECT_HELP_NAME, helper->name);
1682         }
1683
1684         return 0;
1685
1686 nla_put_failure:
1687         return -1;
1688 }
1689
1690 static int
1691 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1692                         int event, const struct nf_conntrack_expect *exp)
1693 {
1694         struct nlmsghdr *nlh;
1695         struct nfgenmsg *nfmsg;
1696         unsigned int flags = pid ? NLM_F_MULTI : 0;
1697
1698         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1699         nlh = nlmsg_put(skb, pid, seq, event, sizeof(*nfmsg), flags);
1700         if (nlh == NULL)
1701                 goto nlmsg_failure;
1702
1703         nfmsg = nlmsg_data(nlh);
1704         nfmsg->nfgen_family = exp->tuple.src.l3num;
1705         nfmsg->version      = NFNETLINK_V0;
1706         nfmsg->res_id       = 0;
1707
1708         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1709                 goto nla_put_failure;
1710
1711         nlmsg_end(skb, nlh);
1712         return skb->len;
1713
1714 nlmsg_failure:
1715 nla_put_failure:
1716         nlmsg_cancel(skb, nlh);
1717         return -1;
1718 }
1719
1720 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1721 static int
1722 ctnetlink_expect_event(unsigned int events, struct nf_exp_event *item)
1723 {
1724         struct nf_conntrack_expect *exp = item->exp;
1725         struct net *net = nf_ct_exp_net(exp);
1726         struct nlmsghdr *nlh;
1727         struct nfgenmsg *nfmsg;
1728         struct sk_buff *skb;
1729         unsigned int type, group;
1730         int flags = 0;
1731
1732         if (events & (1 << IPEXP_DESTROY)) {
1733                 type = IPCTNL_MSG_EXP_DELETE;
1734                 group = NFNLGRP_CONNTRACK_EXP_DESTROY;
1735         } else if (events & (1 << IPEXP_NEW)) {
1736                 type = IPCTNL_MSG_EXP_NEW;
1737                 flags = NLM_F_CREATE|NLM_F_EXCL;
1738                 group = NFNLGRP_CONNTRACK_EXP_NEW;
1739         } else
1740                 return 0;
1741
1742         if (!item->report && !nfnetlink_has_listeners(net, group))
1743                 return 0;
1744
1745         skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1746         if (skb == NULL)
1747                 goto errout;
1748
1749         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1750         nlh = nlmsg_put(skb, item->pid, 0, type, sizeof(*nfmsg), flags);
1751         if (nlh == NULL)
1752                 goto nlmsg_failure;
1753
1754         nfmsg = nlmsg_data(nlh);
1755         nfmsg->nfgen_family = exp->tuple.src.l3num;
1756         nfmsg->version      = NFNETLINK_V0;
1757         nfmsg->res_id       = 0;
1758
1759         rcu_read_lock();
1760         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1761                 goto nla_put_failure;
1762         rcu_read_unlock();
1763
1764         nlmsg_end(skb, nlh);
1765         nfnetlink_send(skb, net, item->pid, group, item->report, GFP_ATOMIC);
1766         return 0;
1767
1768 nla_put_failure:
1769         rcu_read_unlock();
1770         nlmsg_cancel(skb, nlh);
1771 nlmsg_failure:
1772         kfree_skb(skb);
1773 errout:
1774         nfnetlink_set_err(net, 0, 0, -ENOBUFS);
1775         return 0;
1776 }
1777 #endif
1778 static int ctnetlink_exp_done(struct netlink_callback *cb)
1779 {
1780         if (cb->args[1])
1781                 nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
1782         return 0;
1783 }
1784
1785 static int
1786 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1787 {
1788         struct net *net = sock_net(skb->sk);
1789         struct nf_conntrack_expect *exp, *last;
1790         struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1791         struct hlist_node *n;
1792         u_int8_t l3proto = nfmsg->nfgen_family;
1793
1794         rcu_read_lock();
1795         last = (struct nf_conntrack_expect *)cb->args[1];
1796         for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
1797 restart:
1798                 hlist_for_each_entry(exp, n, &net->ct.expect_hash[cb->args[0]],
1799                                      hnode) {
1800                         if (l3proto && exp->tuple.src.l3num != l3proto)
1801                                 continue;
1802                         if (cb->args[1]) {
1803                                 if (exp != last)
1804                                         continue;
1805                                 cb->args[1] = 0;
1806                         }
1807                         if (ctnetlink_exp_fill_info(skb,
1808                                                     NETLINK_CB(cb->skb).pid,
1809                                                     cb->nlh->nlmsg_seq,
1810                                                     IPCTNL_MSG_EXP_NEW,
1811                                                     exp) < 0) {
1812                                 if (!atomic_inc_not_zero(&exp->use))
1813                                         continue;
1814                                 cb->args[1] = (unsigned long)exp;
1815                                 goto out;
1816                         }
1817                 }
1818                 if (cb->args[1]) {
1819                         cb->args[1] = 0;
1820                         goto restart;
1821                 }
1822         }
1823 out:
1824         rcu_read_unlock();
1825         if (last)
1826                 nf_ct_expect_put(last);
1827
1828         return skb->len;
1829 }
1830
1831 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
1832         [CTA_EXPECT_MASTER]     = { .type = NLA_NESTED },
1833         [CTA_EXPECT_TUPLE]      = { .type = NLA_NESTED },
1834         [CTA_EXPECT_MASK]       = { .type = NLA_NESTED },
1835         [CTA_EXPECT_TIMEOUT]    = { .type = NLA_U32 },
1836         [CTA_EXPECT_ID]         = { .type = NLA_U32 },
1837         [CTA_EXPECT_HELP_NAME]  = { .type = NLA_NUL_STRING },
1838         [CTA_EXPECT_ZONE]       = { .type = NLA_U16 },
1839         [CTA_EXPECT_FLAGS]      = { .type = NLA_U32 },
1840 };
1841
1842 static int
1843 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1844                      const struct nlmsghdr *nlh,
1845                      const struct nlattr * const cda[])
1846 {
1847         struct net *net = sock_net(ctnl);
1848         struct nf_conntrack_tuple tuple;
1849         struct nf_conntrack_expect *exp;
1850         struct sk_buff *skb2;
1851         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1852         u_int8_t u3 = nfmsg->nfgen_family;
1853         u16 zone;
1854         int err;
1855
1856         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1857                 struct netlink_dump_control c = {
1858                         .dump = ctnetlink_exp_dump_table,
1859                         .done = ctnetlink_exp_done,
1860                 };
1861                 return netlink_dump_start(ctnl, skb, nlh, &c);
1862         }
1863
1864         err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
1865         if (err < 0)
1866                 return err;
1867
1868         if (cda[CTA_EXPECT_TUPLE])
1869                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1870         else if (cda[CTA_EXPECT_MASTER])
1871                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1872         else
1873                 return -EINVAL;
1874
1875         if (err < 0)
1876                 return err;
1877
1878         exp = nf_ct_expect_find_get(net, zone, &tuple);
1879         if (!exp)
1880                 return -ENOENT;
1881
1882         if (cda[CTA_EXPECT_ID]) {
1883                 __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1884                 if (ntohl(id) != (u32)(unsigned long)exp) {
1885                         nf_ct_expect_put(exp);
1886                         return -ENOENT;
1887                 }
1888         }
1889
1890         err = -ENOMEM;
1891         skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1892         if (skb2 == NULL) {
1893                 nf_ct_expect_put(exp);
1894                 goto out;
1895         }
1896
1897         rcu_read_lock();
1898         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1899                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW, exp);
1900         rcu_read_unlock();
1901         nf_ct_expect_put(exp);
1902         if (err <= 0)
1903                 goto free;
1904
1905         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1906         if (err < 0)
1907                 goto out;
1908
1909         return 0;
1910
1911 free:
1912         kfree_skb(skb2);
1913 out:
1914         /* this avoids a loop in nfnetlink. */
1915         return err == -EAGAIN ? -ENOBUFS : err;
1916 }
1917
1918 static int
1919 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1920                      const struct nlmsghdr *nlh,
1921                      const struct nlattr * const cda[])
1922 {
1923         struct net *net = sock_net(ctnl);
1924         struct nf_conntrack_expect *exp;
1925         struct nf_conntrack_tuple tuple;
1926         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1927         struct hlist_node *n, *next;
1928         u_int8_t u3 = nfmsg->nfgen_family;
1929         unsigned int i;
1930         u16 zone;
1931         int err;
1932
1933         if (cda[CTA_EXPECT_TUPLE]) {
1934                 /* delete a single expect by tuple */
1935                 err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
1936                 if (err < 0)
1937                         return err;
1938
1939                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1940                 if (err < 0)
1941                         return err;
1942
1943                 /* bump usage count to 2 */
1944                 exp = nf_ct_expect_find_get(net, zone, &tuple);
1945                 if (!exp)
1946                         return -ENOENT;
1947
1948                 if (cda[CTA_EXPECT_ID]) {
1949                         __be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
1950                         if (ntohl(id) != (u32)(unsigned long)exp) {
1951                                 nf_ct_expect_put(exp);
1952                                 return -ENOENT;
1953                         }
1954                 }
1955
1956                 /* after list removal, usage count == 1 */
1957                 spin_lock_bh(&nf_conntrack_lock);
1958                 if (del_timer(&exp->timeout)) {
1959                         nf_ct_unlink_expect_report(exp, NETLINK_CB(skb).pid,
1960                                                    nlmsg_report(nlh));
1961                         nf_ct_expect_put(exp);
1962                 }
1963                 spin_unlock_bh(&nf_conntrack_lock);
1964                 /* have to put what we 'get' above.
1965                  * after this line usage count == 0 */
1966                 nf_ct_expect_put(exp);
1967         } else if (cda[CTA_EXPECT_HELP_NAME]) {
1968                 char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
1969                 struct nf_conn_help *m_help;
1970
1971                 /* delete all expectations for this helper */
1972                 spin_lock_bh(&nf_conntrack_lock);
1973                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1974                         hlist_for_each_entry_safe(exp, n, next,
1975                                                   &net->ct.expect_hash[i],
1976                                                   hnode) {
1977                                 m_help = nfct_help(exp->master);
1978                                 if (!strcmp(m_help->helper->name, name) &&
1979                                     del_timer(&exp->timeout)) {
1980                                         nf_ct_unlink_expect_report(exp,
1981                                                         NETLINK_CB(skb).pid,
1982                                                         nlmsg_report(nlh));
1983                                         nf_ct_expect_put(exp);
1984                                 }
1985                         }
1986                 }
1987                 spin_unlock_bh(&nf_conntrack_lock);
1988         } else {
1989                 /* This basically means we have to flush everything*/
1990                 spin_lock_bh(&nf_conntrack_lock);
1991                 for (i = 0; i < nf_ct_expect_hsize; i++) {
1992                         hlist_for_each_entry_safe(exp, n, next,
1993                                                   &net->ct.expect_hash[i],
1994                                                   hnode) {
1995                                 if (del_timer(&exp->timeout)) {
1996                                         nf_ct_unlink_expect_report(exp,
1997                                                         NETLINK_CB(skb).pid,
1998                                                         nlmsg_report(nlh));
1999                                         nf_ct_expect_put(exp);
2000                                 }
2001                         }
2002                 }
2003                 spin_unlock_bh(&nf_conntrack_lock);
2004         }
2005
2006         return 0;
2007 }
2008 static int
2009 ctnetlink_change_expect(struct nf_conntrack_expect *x,
2010                         const struct nlattr * const cda[])
2011 {
2012         return -EOPNOTSUPP;
2013 }
2014
2015 static int
2016 ctnetlink_create_expect(struct net *net, u16 zone,
2017                         const struct nlattr * const cda[],
2018                         u_int8_t u3,
2019                         u32 pid, int report)
2020 {
2021         struct nf_conntrack_tuple tuple, mask, master_tuple;
2022         struct nf_conntrack_tuple_hash *h = NULL;
2023         struct nf_conntrack_expect *exp;
2024         struct nf_conn *ct;
2025         struct nf_conn_help *help;
2026         int err = 0;
2027
2028         /* caller guarantees that those three CTA_EXPECT_* exist */
2029         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
2030         if (err < 0)
2031                 return err;
2032         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
2033         if (err < 0)
2034                 return err;
2035         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
2036         if (err < 0)
2037                 return err;
2038
2039         /* Look for master conntrack of this expectation */
2040         h = nf_conntrack_find_get(net, zone, &master_tuple);
2041         if (!h)
2042                 return -ENOENT;
2043         ct = nf_ct_tuplehash_to_ctrack(h);
2044         exp = nf_ct_expect_alloc(ct);
2045         if (!exp) {
2046                 err = -ENOMEM;
2047                 goto out;
2048         }
2049         help = nfct_help(ct);
2050         if (!help) {
2051                 if (!cda[CTA_EXPECT_TIMEOUT]) {
2052                         err = -EINVAL;
2053                         goto out;
2054                 }
2055                 exp->timeout.expires =
2056                   jiffies + ntohl(nla_get_be32(cda[CTA_EXPECT_TIMEOUT])) * HZ;
2057
2058                 exp->flags = NF_CT_EXPECT_USERSPACE;
2059                 if (cda[CTA_EXPECT_FLAGS]) {
2060                         exp->flags |=
2061                                 ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
2062                 }
2063         } else {
2064                 if (cda[CTA_EXPECT_FLAGS]) {
2065                         exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
2066                         exp->flags &= ~NF_CT_EXPECT_USERSPACE;
2067                 } else
2068                         exp->flags = 0;
2069         }
2070
2071         exp->class = 0;
2072         exp->expectfn = NULL;
2073         exp->master = ct;
2074         exp->helper = NULL;
2075         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
2076         memcpy(&exp->mask.src.u3, &mask.src.u3, sizeof(exp->mask.src.u3));
2077         exp->mask.src.u.all = mask.src.u.all;
2078
2079         err = nf_ct_expect_related_report(exp, pid, report);
2080         nf_ct_expect_put(exp);
2081
2082 out:
2083         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
2084         return err;
2085 }
2086
2087 static int
2088 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
2089                      const struct nlmsghdr *nlh,
2090                      const struct nlattr * const cda[])
2091 {
2092         struct net *net = sock_net(ctnl);
2093         struct nf_conntrack_tuple tuple;
2094         struct nf_conntrack_expect *exp;
2095         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
2096         u_int8_t u3 = nfmsg->nfgen_family;
2097         u16 zone;
2098         int err;
2099
2100         if (!cda[CTA_EXPECT_TUPLE]
2101             || !cda[CTA_EXPECT_MASK]
2102             || !cda[CTA_EXPECT_MASTER])
2103                 return -EINVAL;
2104
2105         err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
2106         if (err < 0)
2107                 return err;
2108
2109         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
2110         if (err < 0)
2111                 return err;
2112
2113         spin_lock_bh(&nf_conntrack_lock);
2114         exp = __nf_ct_expect_find(net, zone, &tuple);
2115
2116         if (!exp) {
2117                 spin_unlock_bh(&nf_conntrack_lock);
2118                 err = -ENOENT;
2119                 if (nlh->nlmsg_flags & NLM_F_CREATE) {
2120                         err = ctnetlink_create_expect(net, zone, cda,
2121                                                       u3,
2122                                                       NETLINK_CB(skb).pid,
2123                                                       nlmsg_report(nlh));
2124                 }
2125                 return err;
2126         }
2127
2128         err = -EEXIST;
2129         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
2130                 err = ctnetlink_change_expect(exp, cda);
2131         spin_unlock_bh(&nf_conntrack_lock);
2132
2133         return err;
2134 }
2135
2136 #ifdef CONFIG_NF_CONNTRACK_EVENTS
2137 static struct nf_ct_event_notifier ctnl_notifier = {
2138         .fcn = ctnetlink_conntrack_event,
2139 };
2140
2141 static struct nf_exp_event_notifier ctnl_notifier_exp = {
2142         .fcn = ctnetlink_expect_event,
2143 };
2144 #endif
2145
2146 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
2147         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
2148                                             .attr_count = CTA_MAX,
2149                                             .policy = ct_nla_policy },
2150         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
2151                                             .attr_count = CTA_MAX,
2152                                             .policy = ct_nla_policy },
2153         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
2154                                             .attr_count = CTA_MAX,
2155                                             .policy = ct_nla_policy },
2156         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
2157                                             .attr_count = CTA_MAX,
2158                                             .policy = ct_nla_policy },
2159 };
2160
2161 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
2162         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
2163                                             .attr_count = CTA_EXPECT_MAX,
2164                                             .policy = exp_nla_policy },
2165         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
2166                                             .attr_count = CTA_EXPECT_MAX,
2167                                             .policy = exp_nla_policy },
2168         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
2169                                             .attr_count = CTA_EXPECT_MAX,
2170                                             .policy = exp_nla_policy },
2171 };
2172
2173 static const struct nfnetlink_subsystem ctnl_subsys = {
2174         .name                           = "conntrack",
2175         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
2176         .cb_count                       = IPCTNL_MSG_MAX,
2177         .cb                             = ctnl_cb,
2178 };
2179
2180 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
2181         .name                           = "conntrack_expect",
2182         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
2183         .cb_count                       = IPCTNL_MSG_EXP_MAX,
2184         .cb                             = ctnl_exp_cb,
2185 };
2186
2187 MODULE_ALIAS("ip_conntrack_netlink");
2188 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
2189 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
2190
2191 static int __net_init ctnetlink_net_init(struct net *net)
2192 {
2193 #ifdef CONFIG_NF_CONNTRACK_EVENTS
2194         int ret;
2195
2196         ret = nf_conntrack_register_notifier(net, &ctnl_notifier);
2197         if (ret < 0) {
2198                 pr_err("ctnetlink_init: cannot register notifier.\n");
2199                 goto err_out;
2200         }
2201
2202         ret = nf_ct_expect_register_notifier(net, &ctnl_notifier_exp);
2203         if (ret < 0) {
2204                 pr_err("ctnetlink_init: cannot expect register notifier.\n");
2205                 goto err_unreg_notifier;
2206         }
2207 #endif
2208         return 0;
2209
2210 #ifdef CONFIG_NF_CONNTRACK_EVENTS
2211 err_unreg_notifier:
2212         nf_conntrack_unregister_notifier(net, &ctnl_notifier);
2213 err_out:
2214         return ret;
2215 #endif
2216 }
2217
2218 static void ctnetlink_net_exit(struct net *net)
2219 {
2220 #ifdef CONFIG_NF_CONNTRACK_EVENTS
2221         nf_ct_expect_unregister_notifier(net, &ctnl_notifier_exp);
2222         nf_conntrack_unregister_notifier(net, &ctnl_notifier);
2223 #endif
2224 }
2225
2226 static void __net_exit ctnetlink_net_exit_batch(struct list_head *net_exit_list)
2227 {
2228         struct net *net;
2229
2230         list_for_each_entry(net, net_exit_list, exit_list)
2231                 ctnetlink_net_exit(net);
2232 }
2233
2234 static struct pernet_operations ctnetlink_net_ops = {
2235         .init           = ctnetlink_net_init,
2236         .exit_batch     = ctnetlink_net_exit_batch,
2237 };
2238
2239 static int __init ctnetlink_init(void)
2240 {
2241         int ret;
2242
2243         pr_info("ctnetlink v%s: registering with nfnetlink.\n", version);
2244         ret = nfnetlink_subsys_register(&ctnl_subsys);
2245         if (ret < 0) {
2246                 pr_err("ctnetlink_init: cannot register with nfnetlink.\n");
2247                 goto err_out;
2248         }
2249
2250         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
2251         if (ret < 0) {
2252                 pr_err("ctnetlink_init: cannot register exp with nfnetlink.\n");
2253                 goto err_unreg_subsys;
2254         }
2255
2256         if (register_pernet_subsys(&ctnetlink_net_ops)) {
2257                 pr_err("ctnetlink_init: cannot register pernet operations\n");
2258                 goto err_unreg_exp_subsys;
2259         }
2260
2261         return 0;
2262
2263 err_unreg_exp_subsys:
2264         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
2265 err_unreg_subsys:
2266         nfnetlink_subsys_unregister(&ctnl_subsys);
2267 err_out:
2268         return ret;
2269 }
2270
2271 static void __exit ctnetlink_exit(void)
2272 {
2273         pr_info("ctnetlink: unregistering from nfnetlink.\n");
2274
2275         unregister_pernet_subsys(&ctnetlink_net_ops);
2276         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
2277         nfnetlink_subsys_unregister(&ctnl_subsys);
2278 }
2279
2280 module_init(ctnetlink_init);
2281 module_exit(ctnetlink_exit);