net/ipv4/tcp_diag.c

   1 /*
   2  * tcp_diag.c   Module for monitoring TCP sockets.
   3  *
   4  * Version:     $Id: tcp_diag.c,v 1.1.1.1 2005/04/11 02:51:13 jack Exp $
   5  *
   6  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 #include <linux/config.h>
  15 #include <linux/module.h>
  16 #include <linux/types.h>
  17 #include <linux/fcntl.h>
  18 #include <linux/random.h>
  19 #include <linux/cache.h>
  20 #include <linux/init.h>
  21
  22 #include <net/icmp.h>
  23 #include <net/tcp.h>
  24 #include <net/ipv6.h>
  25 #include <net/inet_common.h>
  26
  27 #include <linux/inet.h>
  28 #include <linux/stddef.h>
  29
  30 #include <linux/tcp_diag.h>
  31
  32 static struct sock *tcpnl;
  33
  34
  35 #define TCPDIAG_PUT(skb, attrtype, attrlen) \
  36 ({ int rtalen = RTA_LENGTH(attrlen);        \
  37    struct rtattr *rta;                      \
  38    if (skb_tailroom(skb) < RTA_ALIGN(rtalen)) goto nlmsg_failure; \
  39    rta = (void*)__skb_put(skb, RTA_ALIGN(rtalen)); \
  40    rta->rta_type = attrtype;                \
  41    rta->rta_len = rtalen;                   \
  42    RTA_DATA(rta); })
  43
  44 static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
  45                         int ext, u32 pid, u32 seq)
  46 {
  47         struct tcp_opt *tp = &sk->tp_pinfo.af_tcp;
  48         struct tcpdiagmsg *r;
  49         struct nlmsghdr  *nlh;
  50         struct tcp_info  *info = NULL;
  51         struct tcpdiag_meminfo  *minfo = NULL;
  52         unsigned char    *b = skb->tail;
  53
  54         nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
  55         r = NLMSG_DATA(nlh);
  56         if (sk->state != TCP_TIME_WAIT) {
  57                 if (ext & (1<<(TCPDIAG_MEMINFO-1)))
  58                         minfo = TCPDIAG_PUT(skb, TCPDIAG_MEMINFO, sizeof(*minfo));
  59                 if (ext & (1<<(TCPDIAG_INFO-1)))
  60                         info = TCPDIAG_PUT(skb, TCPDIAG_INFO, sizeof(*info));
  61         }
  62         r->tcpdiag_family = sk->family;
  63         r->tcpdiag_state = sk->state;
  64         r->tcpdiag_timer = 0;
  65         r->tcpdiag_retrans = 0;
  66
  67         r->id.tcpdiag_sport = sk->sport;
  68         r->id.tcpdiag_dport = sk->dport;
  69         r->id.tcpdiag_src[0] = sk->rcv_saddr;
  70         r->id.tcpdiag_dst[0] = sk->daddr;
  71         r->id.tcpdiag_if = sk->bound_dev_if;
  72         r->id.tcpdiag_cookie[0] = (u32)(unsigned long)sk;
  73         r->id.tcpdiag_cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1);
  74
  75         if (r->tcpdiag_state == TCP_TIME_WAIT) {
  76                 struct tcp_tw_bucket *tw = (struct tcp_tw_bucket*)sk;
  77                 long tmo = tw->ttd - jiffies;
  78                 if (tmo < 0)
  79                         tmo = 0;
  80
  81                 r->tcpdiag_state = tw->substate;
  82                 r->tcpdiag_timer = 3;
  83                 r->tcpdiag_expires = (tmo*1000+HZ-1)/HZ;
  84                 r->tcpdiag_rqueue = 0;
  85                 r->tcpdiag_wqueue = 0;
  86                 r->tcpdiag_uid = 0;
  87                 r->tcpdiag_inode = 0;
  88 #ifdef CONFIG_IPV6
  89                 if (r->tcpdiag_family == AF_INET6) {
  90                         memcpy(r->id.tcpdiag_src, &tw->v6_rcv_saddr, 16);
  91                         memcpy(r->id.tcpdiag_dst, &tw->v6_daddr, 16);
  92                 }
  93 #endif
  94                 nlh->nlmsg_len = skb->tail - b;
  95                 return skb->len;
  96         }
  97
  98 #ifdef CONFIG_IPV6
  99         if (r->tcpdiag_family == AF_INET6) {
 100                 memcpy(r->id.tcpdiag_src, &sk->net_pinfo.af_inet6.rcv_saddr, 16);
 101                 memcpy(r->id.tcpdiag_dst, &sk->net_pinfo.af_inet6.daddr, 16);
 102         }
 103 #endif
 104
 105 #define EXPIRES_IN_MS(tmo)  ((tmo-jiffies)*1000+HZ-1)/HZ
 106
 107         if (tp->pending == TCP_TIME_RETRANS) {
 108                 r->tcpdiag_timer = 1;
 109                 r->tcpdiag_retrans = tp->retransmits;
 110                 r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
 111         } else if (tp->pending == TCP_TIME_PROBE0) {
 112                 r->tcpdiag_timer = 4;
 113                 r->tcpdiag_retrans = tp->probes_out;
 114                 r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
 115         } else if (timer_pending(&sk->timer)) {
 116                 r->tcpdiag_timer = 2;
 117                 r->tcpdiag_retrans = tp->probes_out;
 118                 r->tcpdiag_expires = EXPIRES_IN_MS(sk->timer.expires);
 119         } else {
 120                 r->tcpdiag_timer = 0;
 121                 r->tcpdiag_expires = 0;
 122         }
 123 #undef EXPIRES_IN_MS
 124
 125         r->tcpdiag_rqueue = tp->rcv_nxt - tp->copied_seq;
 126         r->tcpdiag_wqueue = tp->write_seq - tp->snd_una;
 127         r->tcpdiag_uid = sock_i_uid(sk);
 128         r->tcpdiag_inode = sock_i_ino(sk);
 129
 130         if (minfo) {
 131                 minfo->tcpdiag_rmem = atomic_read(&sk->rmem_alloc);
 132                 minfo->tcpdiag_wmem = sk->wmem_queued;
 133                 minfo->tcpdiag_fmem = sk->forward_alloc;
 134                 minfo->tcpdiag_tmem = atomic_read(&sk->wmem_alloc);
 135         }
 136
 137         if (info) {
 138                 u32 now = tcp_time_stamp;
 139
 140                 info->tcpi_state = sk->state;
 141                 info->tcpi_ca_state = tp->ca_state;
 142                 info->tcpi_retransmits = tp->retransmits;
 143                 info->tcpi_probes = tp->probes_out;
 144                 info->tcpi_backoff = tp->backoff;
 145                 info->tcpi_options = 0;
 146                 if (tp->tstamp_ok)
 147                         info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
 148                 if (tp->sack_ok)
 149                         info->tcpi_options |= TCPI_OPT_SACK;
 150                 if (tp->wscale_ok) {
 151                         info->tcpi_options |= TCPI_OPT_WSCALE;
 152                         info->tcpi_snd_wscale = tp->snd_wscale;
 153                         info->tcpi_rcv_wscale = tp->rcv_wscale;
 154                 } else {
 155                         info->tcpi_snd_wscale = 0;
 156                         info->tcpi_rcv_wscale = 0;
 157                 }
 158 #ifdef CONFIG_INET_ECN
 159                 if (tp->ecn_flags&TCP_ECN_OK)
 160                         info->tcpi_options |= TCPI_OPT_ECN;
 161 #endif
 162
 163                 info->tcpi_rto = (1000000*tp->rto)/HZ;
 164                 info->tcpi_ato = (1000000*tp->ack.ato)/HZ;
 165                 info->tcpi_snd_mss = tp->mss_cache;
 166                 info->tcpi_rcv_mss = tp->ack.rcv_mss;
 167
 168                 info->tcpi_unacked = tp->packets_out;
 169                 info->tcpi_sacked = tp->sacked_out;
 170                 info->tcpi_lost = tp->lost_out;
 171                 info->tcpi_retrans = tp->retrans_out;
 172                 info->tcpi_fackets = tp->fackets_out;
 173
 174                 info->tcpi_last_data_sent = ((now - tp->lsndtime)*1000)/HZ;
 175                 info->tcpi_last_ack_sent = 0;
 176                 info->tcpi_last_data_recv = ((now - tp->ack.lrcvtime)*1000)/HZ;
 177                 info->tcpi_last_ack_recv = ((now - tp->rcv_tstamp)*1000)/HZ;
 178
 179                 info->tcpi_pmtu = tp->pmtu_cookie;
 180                 info->tcpi_rcv_ssthresh = tp->rcv_ssthresh;
 181                 info->tcpi_rtt = ((1000000*tp->srtt)/HZ)>>3;
 182                 info->tcpi_rttvar = ((1000000*tp->mdev)/HZ)>>2;
 183                 info->tcpi_snd_ssthresh = tp->snd_ssthresh;
 184                 info->tcpi_snd_cwnd = tp->snd_cwnd;
 185                 info->tcpi_advmss = tp->advmss;
 186                 info->tcpi_reordering = tp->reordering;
 187         }
 188
 189         nlh->nlmsg_len = skb->tail - b;
 190         return skb->len;
 191
 192 nlmsg_failure:
 193         skb_trim(skb, b - skb->data);
 194         return -1;
 195 }
 196
 197 extern struct sock *tcp_v4_lookup(u32 saddr, u16 sport, u32 daddr, u16 dport, int dif);
 198 #ifdef CONFIG_IPV6
 199 extern struct sock *tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
 200                                   struct in6_addr *daddr, u16 dport,
 201                                   int dif);
 202 #endif
 203
 204 static int tcpdiag_get_exact(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 205 {
 206         int err;
 207         struct sock *sk;
 208         struct tcpdiagreq *req = NLMSG_DATA(nlh);
 209         struct sk_buff *rep;
 210
 211         if (req->tcpdiag_family == AF_INET) {
 212                 sk = tcp_v4_lookup(req->id.tcpdiag_dst[0], req->id.tcpdiag_dport,
 213                                    req->id.tcpdiag_src[0], req->id.tcpdiag_sport,
 214                                    req->id.tcpdiag_if);
 215         }
 216 #ifdef CONFIG_IPV6
 217         else if (req->tcpdiag_family == AF_INET6) {
 218                 sk = tcp_v6_lookup((struct in6_addr*)req->id.tcpdiag_dst, req->id.tcpdiag_dport,
 219                                    (struct in6_addr*)req->id.tcpdiag_src, req->id.tcpdiag_sport,
 220                                    req->id.tcpdiag_if);
 221         }
 222 #endif
 223         else {
 224                 return -EINVAL;
 225         }
 226
 227         if (sk == NULL)
 228                 return -ENOENT;
 229
 230         err = -ESTALE;
 231         if ((req->id.tcpdiag_cookie[0] != TCPDIAG_NOCOOKIE ||
 232              req->id.tcpdiag_cookie[1] != TCPDIAG_NOCOOKIE) &&
 233             ((u32)(unsigned long)sk != req->id.tcpdiag_cookie[0] ||
 234              (u32)((((unsigned long)sk) >> 31) >> 1) != req->id.tcpdiag_cookie[1]))
 235                 goto out;
 236
 237         err = -ENOMEM;
 238         rep = alloc_skb(NLMSG_SPACE(sizeof(struct tcpdiagmsg)+
 239                                     sizeof(struct tcpdiag_meminfo)+
 240                                     sizeof(struct tcp_info)+64), GFP_KERNEL);
 241         if (!rep)
 242                 goto out;
 243
 244         if (tcpdiag_fill(rep, sk, req->tcpdiag_ext,
 245                          NETLINK_CB(in_skb).pid,
 246                          nlh->nlmsg_seq) <= 0)
 247                 BUG();
 248
 249         err = netlink_unicast(tcpnl, rep, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
 250         if (err > 0)
 251                 err = 0;
 252
 253 out:
 254         if (sk) {
 255                 if (sk->state == TCP_TIME_WAIT)
 256                         tcp_tw_put((struct tcp_tw_bucket*)sk);
 257                 else
 258                         sock_put(sk);
 259         }
 260         return err;
 261 }
 262
 263 int bitstring_match(u32 *a1, u32 *a2, int bits)
 264 {
 265         int words = bits >> 5;
 266
 267         bits &= 0x1f;
 268
 269         if (words) {
 270                 if (memcmp(a1, a2, words << 2))
 271                         return 0;
 272         }
 273         if (bits) {
 274                 __u32 w1, w2;
 275                 __u32 mask;
 276
 277                 w1 = a1[words];
 278                 w2 = a2[words];
 279
 280                 mask = htonl((0xffffffff) << (32 - bits));
 281
 282                 if ((w1 ^ w2) & mask)
 283                         return 0;
 284         }
 285
 286         return 1;
 287 }
 288
 289
 290 int tcpdiag_bc_run(char *bc, int len, struct sock *sk)
 291 {
 292         while (len > 0) {
 293                 int yes = 1;
 294                 struct tcpdiag_bc_op *op = (struct tcpdiag_bc_op*)bc;
 295
 296                 switch (op->code) {
 297                 case TCPDIAG_BC_NOP:
 298                         break;
 299                 case TCPDIAG_BC_JMP:
 300                         yes = 0;
 301                         break;
 302                 case TCPDIAG_BC_S_GE:
 303                         yes = (sk->num >= op[1].no);
 304                         break;
 305                 case TCPDIAG_BC_S_LE:
 306                         yes = (sk->num <= op[1].no);
 307                         break;
 308                 case TCPDIAG_BC_D_GE:
 309                         yes = (ntohs(sk->dport) >= op[1].no);
 310                         break;
 311                 case TCPDIAG_BC_D_LE:
 312                         yes = (ntohs(sk->dport) <= op[1].no);
 313                         break;
 314                 case TCPDIAG_BC_AUTO:
 315                         yes = !(sk->userlocks&SOCK_BINDPORT_LOCK);
 316                         break;
 317                 case TCPDIAG_BC_S_COND:
 318                 case TCPDIAG_BC_D_COND:
 319                 {
 320                         struct tcpdiag_hostcond *cond = (struct tcpdiag_hostcond*)(op+1);
 321                         u32 *addr;
 322
 323                         if (cond->port != -1 &&
 324                             cond->port != (op->code == TCPDIAG_BC_S_COND ? sk->num : ntohs(sk->dport))) {
 325                                 yes = 0;
 326                                 break;
 327                         }
 328
 329                         if (cond->prefix_len == 0)
 330                                 break;
 331
 332 #ifdef CONFIG_IPV6
 333                         if (sk->family == AF_INET6) {
 334                                 if (op->code == TCPDIAG_BC_S_COND)
 335                                         addr = (u32*)&sk->net_pinfo.af_inet6.rcv_saddr;
 336                                 else
 337                                         addr = (u32*)&sk->net_pinfo.af_inet6.daddr;
 338                         } else
 339 #endif
 340                         {
 341                                 if (op->code == TCPDIAG_BC_S_COND)
 342                                         addr = &sk->rcv_saddr;
 343                                 else
 344                                         addr = &sk->daddr;
 345                         }
 346
 347                         if (bitstring_match(addr, cond->addr, cond->prefix_len))
 348                                 break;
 349                         if (sk->family == AF_INET6 && cond->family == AF_INET) {
 350                                 if (addr[0] == 0 && addr[1] == 0 &&
 351                                     addr[2] == htonl(0xffff) &&
 352                                     bitstring_match(addr+3, cond->addr, cond->prefix_len))
 353                                         break;
 354                         }
 355                         yes = 0;
 356                         break;
 357                 }
 358                 }
 359
 360                 if (yes) {
 361                         len -= op->yes;
 362                         bc += op->yes;
 363                 } else {
 364                         len -= op->no;
 365                         bc += op->no;
 366                 }
 367         }
 368         return (len == 0);
 369 }
 370
 371 int valid_cc(char *bc, int len, int cc)
 372 {
 373         while (len >= 0) {
 374                 struct tcpdiag_bc_op *op = (struct tcpdiag_bc_op*)bc;
 375
 376                 if (cc > len)
 377                         return 0;
 378                 if (cc == len)
 379                         return 1;
 380                 if (op->yes < 4)
 381                         return 0;
 382                 len -= op->yes;
 383                 bc  += op->yes;
 384         }
 385         return 0;
 386 }
 387
 388 int tcpdiag_bc_audit(char *bytecode, int bytecode_len)
 389 {
 390         char *bc = bytecode;
 391         int  len = bytecode_len;
 392
 393         while (len > 0) {
 394                 struct tcpdiag_bc_op *op = (struct tcpdiag_bc_op*)bc;
 395
 396 //printk("BC: %d %d %d {%d} / %d\n", op->code, op->yes, op->no, op[1].no, len);
 397                 switch (op->code) {
 398                 case TCPDIAG_BC_AUTO:
 399                 case TCPDIAG_BC_S_COND:
 400                 case TCPDIAG_BC_D_COND:
 401                 case TCPDIAG_BC_S_GE:
 402                 case TCPDIAG_BC_S_LE:
 403                 case TCPDIAG_BC_D_GE:
 404                 case TCPDIAG_BC_D_LE:
 405                         if (op->yes < 4 || op->yes > len+4)
 406                                 return -EINVAL;
 407                 case TCPDIAG_BC_JMP:
 408                         if (op->no < 4 || op->no > len+4)
 409                                 return -EINVAL;
 410                         if (op->no < len &&
 411                             !valid_cc(bytecode, bytecode_len, len-op->no))
 412                                 return -EINVAL;
 413                         break;
 414                 case TCPDIAG_BC_NOP:
 415                         if (op->yes < 4 || op->yes > len+4)
 416                                 return -EINVAL;
 417                         break;
 418                 default:
 419                         return -EINVAL;
 420                 }
 421                 bc += op->yes;
 422                 len -= op->yes;
 423         }
 424         return len == 0 ? 0 : -EINVAL;
 425 }
 426
 427
 428 int tcpdiag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 429 {
 430         int i, num;
 431         int s_i, s_num;
 432         struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
 433         struct rtattr *bc = NULL;
 434
 435         if (cb->nlh->nlmsg_len > 4+NLMSG_SPACE(sizeof(struct tcpdiagreq)))
 436                 bc = (struct rtattr*)(r+1);
 437
 438         s_i = cb->args[1];
 439         s_num = num = cb->args[2];
 440
 441         if (cb->args[0] == 0) {
 442                 if (!(r->tcpdiag_states&(TCPF_LISTEN|TCPF_SYN_RECV)))
 443                         goto skip_listen_ht;
 444                 tcp_listen_lock();
 445                 for (i = s_i; i < TCP_LHTABLE_SIZE; i++) {
 446                         struct sock *sk = tcp_listening_hash[i];
 447
 448                         if (i > s_i)
 449                                 s_num = 0;
 450
 451                         for (sk = tcp_listening_hash[i], num = 0;
 452                              sk != NULL;
 453                              sk = sk->next, num++) {
 454                                 if (num < s_num)
 455                                         continue;
 456                                 if (!(r->tcpdiag_states&TCPF_LISTEN) ||
 457                                     r->id.tcpdiag_dport)
 458                                         continue;
 459                                 if (r->id.tcpdiag_sport != sk->sport && r->id.tcpdiag_sport)
 460                                         continue;
 461                                 if (bc && !tcpdiag_bc_run(RTA_DATA(bc), RTA_PAYLOAD(bc), sk))
 462                                         continue;
 463                                 if (tcpdiag_fill(skb, sk, r->tcpdiag_ext,
 464                                                  NETLINK_CB(cb->skb).pid,
 465                                                  cb->nlh->nlmsg_seq) <= 0) {
 466                                         tcp_listen_unlock();
 467                                         goto done;
 468                                 }
 469                         }
 470                 }
 471                 tcp_listen_unlock();
 472 skip_listen_ht:
 473                 cb->args[0] = 1;
 474                 s_i = num = s_num = 0;
 475         }
 476
 477         if (!(r->tcpdiag_states&~(TCPF_LISTEN|TCPF_SYN_RECV)))
 478                 return skb->len;
 479
 480         for (i = s_i; i < tcp_ehash_size; i++) {
 481                 struct tcp_ehash_bucket *head = &tcp_ehash[i];
 482                 struct sock *sk;
 483
 484                 if (i > s_i)
 485                         s_num = 0;
 486
 487                 read_lock_bh(&head->lock);
 488
 489                 for (sk = head->chain, num = 0;
 490                      sk != NULL;
 491                      sk = sk->next, num++) {
 492                         if (num < s_num)
 493                                 continue;
 494                         if (!(r->tcpdiag_states&(1<<sk->state)))
 495                                 continue;
 496                         if (r->id.tcpdiag_sport != sk->sport && r->id.tcpdiag_sport)
 497                                 continue;
 498                         if (r->id.tcpdiag_dport != sk->dport && r->id.tcpdiag_dport)
 499                                 continue;
 500                         if (bc && !tcpdiag_bc_run(RTA_DATA(bc), RTA_PAYLOAD(bc), sk))
 501                                 continue;
 502                         if (tcpdiag_fill(skb, sk, r->tcpdiag_ext,
 503                                          NETLINK_CB(cb->skb).pid,
 504                                          cb->nlh->nlmsg_seq) <= 0) {
 505                                 read_unlock_bh(&head->lock);
 506                                 goto done;
 507                         }
 508                 }
 509
 510                 if (r->tcpdiag_states&TCPF_TIME_WAIT) {
 511                         for (sk = tcp_ehash[i+tcp_ehash_size].chain;
 512                              sk != NULL;
 513                              sk = sk->next, num++) {
 514                                 if (num < s_num)
 515                                         continue;
 516                                 if (!(r->tcpdiag_states&(1<<sk->zapped)))
 517                                         continue;
 518                                 if (r->id.tcpdiag_sport != sk->sport && r->id.tcpdiag_sport)
 519                                         continue;
 520                                 if (r->id.tcpdiag_dport != sk->dport && r->id.tcpdiag_dport)
 521                                         continue;
 522                                 if (bc && !tcpdiag_bc_run(RTA_DATA(bc), RTA_PAYLOAD(bc), sk))
 523                                         continue;
 524                                 if (tcpdiag_fill(skb, sk, r->tcpdiag_ext,
 525                                                  NETLINK_CB(cb->skb).pid,
 526                                                  cb->nlh->nlmsg_seq) <= 0) {
 527                                         read_unlock_bh(&head->lock);
 528                                         goto done;
 529                                 }
 530                         }
 531                 }
 532                 read_unlock_bh(&head->lock);
 533         }
 534
 535 done:
 536         cb->args[1] = i;
 537         cb->args[2] = num;
 538         return skb->len;
 539 }
 540
 541 static int tcpdiag_dump_done(struct netlink_callback *cb)
 542 {
 543         return 0;
 544 }
 545
 546
 547 static __inline__ int
 548 tcpdiag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 549 {
 550         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
 551                 return 0;
 552
 553         if (nlh->nlmsg_type != TCPDIAG_GETSOCK)
 554                 goto err_inval;
 555
 556         if (NLMSG_LENGTH(sizeof(struct tcpdiagreq)) > skb->len)
 557                 goto err_inval;
 558
 559         if (nlh->nlmsg_flags&NLM_F_DUMP) {
 560                 if (nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(struct tcpdiagreq))) {
 561                         struct rtattr *rta = (struct rtattr*)(NLMSG_DATA(nlh) + sizeof(struct tcpdiagreq));
 562                         if (rta->rta_type != TCPDIAG_REQ_BYTECODE ||
 563                             rta->rta_len < 8 ||
 564                             rta->rta_len > nlh->nlmsg_len - NLMSG_SPACE(sizeof(struct tcpdiagreq)))
 565                                 goto err_inval;
 566                         if (tcpdiag_bc_audit(RTA_DATA(rta), RTA_PAYLOAD(rta)))
 567                                 goto err_inval;
 568                 }
 569                 return netlink_dump_start(tcpnl, skb, nlh,
 570                                           tcpdiag_dump,
 571                                           tcpdiag_dump_done);
 572         } else {
 573                 return tcpdiag_get_exact(skb, nlh);
 574         }
 575
 576 err_inval:
 577         return -EINVAL;
 578 }
 579
 580
 581 extern __inline__ void tcpdiag_rcv_skb(struct sk_buff *skb)
 582 {
 583         int err;
 584         struct nlmsghdr * nlh;
 585
 586         if (skb->len >= NLMSG_SPACE(0)) {
 587                 nlh = (struct nlmsghdr *)skb->data;
 588                 if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
 589                         return;
 590                 err = tcpdiag_rcv_msg(skb, nlh);
 591                 if (err)
 592                         netlink_ack(skb, nlh, err);
 593         }
 594 }
 595
 596 static void tcpdiag_rcv(struct sock *sk, int len)
 597 {
 598         struct sk_buff *skb;
 599
 600         while ((skb = skb_dequeue(&sk->receive_queue)) != NULL) {
 601                 tcpdiag_rcv_skb(skb);
 602                 kfree_skb(skb);
 603         }
 604 }
 605
 606 void __init tcpdiag_init(void)
 607 {
 608         tcpnl = netlink_kernel_create(NETLINK_TCPDIAG, tcpdiag_rcv);
 609         if (tcpnl == NULL)
 610                 panic("tcpdiag_init: Cannot create netlink socket.");
 611 }