net/ipv4/tcp_diag.c

   1 /*
   2  * tcp_diag.c   Module for monitoring TCP sockets.
   3  *
   4  * Version:     $Id: tcp_diag.c,v 1.3 2002/02/01 22:01:04 davem 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 #include <linux/time.h>
  22
  23 #include <net/icmp.h>
  24 #include <net/tcp.h>
  25 #include <net/ipv6.h>
  26 #include <net/inet_common.h>
  27
  28 #include <linux/inet.h>
  29 #include <linux/stddef.h>
  30
  31 #include <linux/tcp_diag.h>
  32
  33 struct tcpdiag_entry
  34 {
  35         u32 *saddr;
  36         u32 *daddr;
  37         u16 sport;
  38         u16 dport;
  39         u16 family;
  40         u16 userlocks;
  41 };
  42
  43 static struct sock *tcpnl;
  44
  45
  46 #define TCPDIAG_PUT(skb, attrtype, attrlen) \
  47 ({ int rtalen = RTA_LENGTH(attrlen);        \
  48    struct rtattr *rta;                      \
  49    if (skb_tailroom(skb) < RTA_ALIGN(rtalen)) goto nlmsg_failure; \
  50    rta = (void*)__skb_put(skb, RTA_ALIGN(rtalen)); \
  51    rta->rta_type = attrtype;                \
  52    rta->rta_len = rtalen;                   \
  53    RTA_DATA(rta); })
  54
  55 static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
  56                         int ext, u32 pid, u32 seq, u16 nlmsg_flags)
  57 {
  58         struct inet_sock *inet = inet_sk(sk);
  59         struct tcp_sock *tp = tcp_sk(sk);
  60         struct tcpdiagmsg *r;
  61         struct nlmsghdr  *nlh;
  62         struct tcp_info  *info = NULL;
  63         struct tcpdiag_meminfo  *minfo = NULL;
  64         struct tcpvegas_info *vinfo = NULL;
  65         unsigned char    *b = skb->tail;
  66
  67         nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
  68         nlh->nlmsg_flags = nlmsg_flags;
  69         r = NLMSG_DATA(nlh);
  70         if (sk->sk_state != TCP_TIME_WAIT) {
  71                 if (ext & (1<<(TCPDIAG_MEMINFO-1)))
  72                         minfo = TCPDIAG_PUT(skb, TCPDIAG_MEMINFO, sizeof(*minfo));
  73                 if (ext & (1<<(TCPDIAG_INFO-1)))
  74                         info = TCPDIAG_PUT(skb, TCPDIAG_INFO, sizeof(*info));
  75
  76                 if ((tcp_is_westwood(tp) || tcp_is_vegas(tp))
  77                     && (ext & (1<<(TCPDIAG_VEGASINFO-1))))
  78                         vinfo = TCPDIAG_PUT(skb, TCPDIAG_VEGASINFO, sizeof(*vinfo));
  79         }
  80         r->tcpdiag_family = sk->sk_family;
  81         r->tcpdiag_state = sk->sk_state;
  82         r->tcpdiag_timer = 0;
  83         r->tcpdiag_retrans = 0;
  84
  85         r->id.tcpdiag_if = sk->sk_bound_dev_if;
  86         r->id.tcpdiag_cookie[0] = (u32)(unsigned long)sk;
  87         r->id.tcpdiag_cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1);
  88
  89         if (r->tcpdiag_state == TCP_TIME_WAIT) {
  90                 struct tcp_tw_bucket *tw = (struct tcp_tw_bucket*)sk;
  91                 long tmo = tw->tw_ttd - jiffies;
  92                 if (tmo < 0)
  93                         tmo = 0;
  94
  95                 r->id.tcpdiag_sport = tw->tw_sport;
  96                 r->id.tcpdiag_dport = tw->tw_dport;
  97                 r->id.tcpdiag_src[0] = tw->tw_rcv_saddr;
  98                 r->id.tcpdiag_dst[0] = tw->tw_daddr;
  99                 r->tcpdiag_state = tw->tw_substate;
 100                 r->tcpdiag_timer = 3;
 101                 r->tcpdiag_expires = (tmo*1000+HZ-1)/HZ;
 102                 r->tcpdiag_rqueue = 0;
 103                 r->tcpdiag_wqueue = 0;
 104                 r->tcpdiag_uid = 0;
 105                 r->tcpdiag_inode = 0;
 106 #ifdef CONFIG_IP_TCPDIAG_IPV6
 107                 if (r->tcpdiag_family == AF_INET6) {
 108                         ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_src,
 109                                        &tw->tw_v6_rcv_saddr);
 110                         ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_dst,
 111                                        &tw->tw_v6_daddr);
 112                 }
 113 #endif
 114                 nlh->nlmsg_len = skb->tail - b;
 115                 return skb->len;
 116         }
 117
 118         r->id.tcpdiag_sport = inet->sport;
 119         r->id.tcpdiag_dport = inet->dport;
 120         r->id.tcpdiag_src[0] = inet->rcv_saddr;
 121         r->id.tcpdiag_dst[0] = inet->daddr;
 122
 123 #ifdef CONFIG_IP_TCPDIAG_IPV6
 124         if (r->tcpdiag_family == AF_INET6) {
 125                 struct ipv6_pinfo *np = inet6_sk(sk);
 126
 127                 ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_src,
 128                                &np->rcv_saddr);
 129                 ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_dst,
 130                                &np->daddr);
 131         }
 132 #endif
 133
 134 #define EXPIRES_IN_MS(tmo)  ((tmo-jiffies)*1000+HZ-1)/HZ
 135
 136         if (tp->pending == TCP_TIME_RETRANS) {
 137                 r->tcpdiag_timer = 1;
 138                 r->tcpdiag_retrans = tp->retransmits;
 139                 r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
 140         } else if (tp->pending == TCP_TIME_PROBE0) {
 141                 r->tcpdiag_timer = 4;
 142                 r->tcpdiag_retrans = tp->probes_out;
 143                 r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
 144         } else if (timer_pending(&sk->sk_timer)) {
 145                 r->tcpdiag_timer = 2;
 146                 r->tcpdiag_retrans = tp->probes_out;
 147                 r->tcpdiag_expires = EXPIRES_IN_MS(sk->sk_timer.expires);
 148         } else {
 149                 r->tcpdiag_timer = 0;
 150                 r->tcpdiag_expires = 0;
 151         }
 152 #undef EXPIRES_IN_MS
 153
 154         r->tcpdiag_rqueue = tp->rcv_nxt - tp->copied_seq;
 155         r->tcpdiag_wqueue = tp->write_seq - tp->snd_una;
 156         r->tcpdiag_uid = sock_i_uid(sk);
 157         r->tcpdiag_inode = sock_i_ino(sk);
 158
 159         if (minfo) {
 160                 minfo->tcpdiag_rmem = atomic_read(&sk->sk_rmem_alloc);
 161                 minfo->tcpdiag_wmem = sk->sk_wmem_queued;
 162                 minfo->tcpdiag_fmem = sk->sk_forward_alloc;
 163                 minfo->tcpdiag_tmem = atomic_read(&sk->sk_wmem_alloc);
 164         }
 165
 166         if (info)
 167                 tcp_get_info(sk, info);
 168
 169         if (vinfo) {
 170                 if (tcp_is_vegas(tp)) {
 171                         vinfo->tcpv_enabled = tp->vegas.doing_vegas_now;
 172                         vinfo->tcpv_rttcnt = tp->vegas.cntRTT;
 173                         vinfo->tcpv_rtt = jiffies_to_usecs(tp->vegas.baseRTT);
 174                         vinfo->tcpv_minrtt = jiffies_to_usecs(tp->vegas.minRTT);
 175                 } else {
 176                         vinfo->tcpv_enabled = 0;
 177                         vinfo->tcpv_rttcnt = 0;
 178                         vinfo->tcpv_rtt = jiffies_to_usecs(tp->westwood.rtt);
 179                         vinfo->tcpv_minrtt = jiffies_to_usecs(tp->westwood.rtt_min);
 180                 }
 181         }
 182
 183         nlh->nlmsg_len = skb->tail - b;
 184         return skb->len;
 185
 186 nlmsg_failure:
 187         skb_trim(skb, b - skb->data);
 188         return -1;
 189 }
 190
 191 extern struct sock *tcp_v4_lookup(u32 saddr, u16 sport, u32 daddr, u16 dport,
 192                                   int dif);
 193 #ifdef CONFIG_IP_TCPDIAG_IPV6
 194 extern struct sock *tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
 195                                   struct in6_addr *daddr, u16 dport,
 196                                   int dif);
 197 #else
 198 static inline struct sock *tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
 199                                          struct in6_addr *daddr, u16 dport,
 200                                          int dif)
 201 {
 202         return NULL;
 203 }
 204 #endif
 205
 206 static int tcpdiag_get_exact(struct sk_buff *in_skb, const struct nlmsghdr *nlh)
 207 {
 208         int err;
 209         struct sock *sk;
 210         struct tcpdiagreq *req = NLMSG_DATA(nlh);
 211         struct sk_buff *rep;
 212
 213         if (req->tcpdiag_family == AF_INET) {
 214                 sk = tcp_v4_lookup(req->id.tcpdiag_dst[0], req->id.tcpdiag_dport,
 215                                    req->id.tcpdiag_src[0], req->id.tcpdiag_sport,
 216                                    req->id.tcpdiag_if);
 217         }
 218 #ifdef CONFIG_IP_TCPDIAG_IPV6
 219         else if (req->tcpdiag_family == AF_INET6) {
 220                 sk = tcp_v6_lookup((struct in6_addr*)req->id.tcpdiag_dst, req->id.tcpdiag_dport,
 221                                    (struct in6_addr*)req->id.tcpdiag_src, req->id.tcpdiag_sport,
 222                                    req->id.tcpdiag_if);
 223         }
 224 #endif
 225         else {
 226                 return -EINVAL;
 227         }
 228
 229         if (sk == NULL)
 230                 return -ENOENT;
 231
 232         err = -ESTALE;
 233         if ((req->id.tcpdiag_cookie[0] != TCPDIAG_NOCOOKIE ||
 234              req->id.tcpdiag_cookie[1] != TCPDIAG_NOCOOKIE) &&
 235             ((u32)(unsigned long)sk != req->id.tcpdiag_cookie[0] ||
 236              (u32)((((unsigned long)sk) >> 31) >> 1) != req->id.tcpdiag_cookie[1]))
 237                 goto out;
 238
 239         err = -ENOMEM;
 240         rep = alloc_skb(NLMSG_SPACE(sizeof(struct tcpdiagmsg)+
 241                                     sizeof(struct tcpdiag_meminfo)+
 242                                     sizeof(struct tcp_info)+64), GFP_KERNEL);
 243         if (!rep)
 244                 goto out;
 245
 246         if (tcpdiag_fill(rep, sk, req->tcpdiag_ext,
 247                          NETLINK_CB(in_skb).pid,
 248                          nlh->nlmsg_seq, 0) <= 0)
 249                 BUG();
 250
 251         err = netlink_unicast(tcpnl, rep, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
 252         if (err > 0)
 253                 err = 0;
 254
 255 out:
 256         if (sk) {
 257                 if (sk->sk_state == TCP_TIME_WAIT)
 258                         tcp_tw_put((struct tcp_tw_bucket*)sk);
 259                 else
 260                         sock_put(sk);
 261         }
 262         return err;
 263 }
 264
 265 static int bitstring_match(const u32 *a1, const u32 *a2, int bits)
 266 {
 267         int words = bits >> 5;
 268
 269         bits &= 0x1f;
 270
 271         if (words) {
 272                 if (memcmp(a1, a2, words << 2))
 273                         return 0;
 274         }
 275         if (bits) {
 276                 __u32 w1, w2;
 277                 __u32 mask;
 278
 279                 w1 = a1[words];
 280                 w2 = a2[words];
 281
 282                 mask = htonl((0xffffffff) << (32 - bits));
 283
 284                 if ((w1 ^ w2) & mask)
 285                         return 0;
 286         }
 287
 288         return 1;
 289 }
 290
 291
 292 static int tcpdiag_bc_run(const void *bc, int len,
 293                           const struct tcpdiag_entry *entry)
 294 {
 295         while (len > 0) {
 296                 int yes = 1;
 297                 const struct tcpdiag_bc_op *op = bc;
 298
 299                 switch (op->code) {
 300                 case TCPDIAG_BC_NOP:
 301                         break;
 302                 case TCPDIAG_BC_JMP:
 303                         yes = 0;
 304                         break;
 305                 case TCPDIAG_BC_S_GE:
 306                         yes = entry->sport >= op[1].no;
 307                         break;
 308                 case TCPDIAG_BC_S_LE:
 309                         yes = entry->dport <= op[1].no;
 310                         break;
 311                 case TCPDIAG_BC_D_GE:
 312                         yes = entry->dport >= op[1].no;
 313                         break;
 314                 case TCPDIAG_BC_D_LE:
 315                         yes = entry->dport <= op[1].no;
 316                         break;
 317                 case TCPDIAG_BC_AUTO:
 318                         yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
 319                         break;
 320                 case TCPDIAG_BC_S_COND:
 321                 case TCPDIAG_BC_D_COND:
 322                 {
 323                         struct tcpdiag_hostcond *cond = (struct tcpdiag_hostcond*)(op+1);
 324                         u32 *addr;
 325
 326                         if (cond->port != -1 &&
 327                             cond->port != (op->code == TCPDIAG_BC_S_COND ?
 328                                              entry->sport : entry->dport)) {
 329                                 yes = 0;
 330                                 break;
 331                         }
 332
 333                         if (cond->prefix_len == 0)
 334                                 break;
 335
 336                         if (op->code == TCPDIAG_BC_S_COND)
 337                                 addr = entry->saddr;
 338                         else
 339                                 addr = entry->daddr;
 340
 341                         if (bitstring_match(addr, cond->addr, cond->prefix_len))
 342                                 break;
 343                         if (entry->family == AF_INET6 &&
 344                             cond->family == AF_INET) {
 345                                 if (addr[0] == 0 && addr[1] == 0 &&
 346                                     addr[2] == htonl(0xffff) &&
 347                                     bitstring_match(addr+3, cond->addr, cond->prefix_len))
 348                                         break;
 349                         }
 350                         yes = 0;
 351                         break;
 352                 }
 353                 }
 354
 355                 if (yes) {
 356                         len -= op->yes;
 357                         bc += op->yes;
 358                 } else {
 359                         len -= op->no;
 360                         bc += op->no;
 361                 }
 362         }
 363         return (len == 0);
 364 }
 365
 366 static int valid_cc(const void *bc, int len, int cc)
 367 {
 368         while (len >= 0) {
 369                 const struct tcpdiag_bc_op *op = bc;
 370
 371                 if (cc > len)
 372                         return 0;
 373                 if (cc == len)
 374                         return 1;
 375                 if (op->yes < 4)
 376                         return 0;
 377                 len -= op->yes;
 378                 bc  += op->yes;
 379         }
 380         return 0;
 381 }
 382
 383 static int tcpdiag_bc_audit(const void *bytecode, int bytecode_len)
 384 {
 385         const unsigned char *bc = bytecode;
 386         int  len = bytecode_len;
 387
 388         while (len > 0) {
 389                 struct tcpdiag_bc_op *op = (struct tcpdiag_bc_op*)bc;
 390
 391 //printk("BC: %d %d %d {%d} / %d\n", op->code, op->yes, op->no, op[1].no, len);
 392                 switch (op->code) {
 393                 case TCPDIAG_BC_AUTO:
 394                 case TCPDIAG_BC_S_COND:
 395                 case TCPDIAG_BC_D_COND:
 396                 case TCPDIAG_BC_S_GE:
 397                 case TCPDIAG_BC_S_LE:
 398                 case TCPDIAG_BC_D_GE:
 399                 case TCPDIAG_BC_D_LE:
 400                         if (op->yes < 4 || op->yes > len+4)
 401                                 return -EINVAL;
 402                 case TCPDIAG_BC_JMP:
 403                         if (op->no < 4 || op->no > len+4)
 404                                 return -EINVAL;
 405                         if (op->no < len &&
 406                             !valid_cc(bytecode, bytecode_len, len-op->no))
 407                                 return -EINVAL;
 408                         break;
 409                 case TCPDIAG_BC_NOP:
 410                         if (op->yes < 4 || op->yes > len+4)
 411                                 return -EINVAL;
 412                         break;
 413                 default:
 414                         return -EINVAL;
 415                 }
 416                 bc += op->yes;
 417                 len -= op->yes;
 418         }
 419         return len == 0 ? 0 : -EINVAL;
 420 }
 421
 422 static int tcpdiag_dump_sock(struct sk_buff *skb, struct sock *sk,
 423                              struct netlink_callback *cb)
 424 {
 425         struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
 426
 427         if (cb->nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(*r))) {
 428                 struct tcpdiag_entry entry;
 429                 struct rtattr *bc = (struct rtattr *)(r + 1);
 430                 struct inet_sock *inet = inet_sk(sk);
 431
 432                 entry.family = sk->sk_family;
 433 #ifdef CONFIG_IP_TCPDIAG_IPV6
 434                 if (entry.family == AF_INET6) {
 435                         struct ipv6_pinfo *np = inet6_sk(sk);
 436
 437                         entry.saddr = np->rcv_saddr.s6_addr32;
 438                         entry.daddr = np->daddr.s6_addr32;
 439                 } else
 440 #endif
 441                 {
 442                         entry.saddr = &inet->rcv_saddr;
 443                         entry.daddr = &inet->daddr;
 444                 }
 445                 entry.sport = inet->num;
 446                 entry.dport = ntohs(inet->dport);
 447                 entry.userlocks = sk->sk_userlocks;
 448
 449                 if (!tcpdiag_bc_run(RTA_DATA(bc), RTA_PAYLOAD(bc), &entry))
 450                         return 0;
 451         }
 452
 453         return tcpdiag_fill(skb, sk, r->tcpdiag_ext, NETLINK_CB(cb->skb).pid,
 454                             cb->nlh->nlmsg_seq, NLM_F_MULTI);
 455 }
 456
 457 static int tcpdiag_fill_req(struct sk_buff *skb, struct sock *sk,
 458                             struct open_request *req,
 459                             u32 pid, u32 seq)
 460 {
 461         struct inet_sock *inet = inet_sk(sk);
 462         unsigned char *b = skb->tail;
 463         struct tcpdiagmsg *r;
 464         struct nlmsghdr *nlh;
 465         long tmo;
 466
 467         nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
 468         nlh->nlmsg_flags = NLM_F_MULTI;
 469         r = NLMSG_DATA(nlh);
 470
 471         r->tcpdiag_family = sk->sk_family;
 472         r->tcpdiag_state = TCP_SYN_RECV;
 473         r->tcpdiag_timer = 1;
 474         r->tcpdiag_retrans = req->retrans;
 475
 476         r->id.tcpdiag_if = sk->sk_bound_dev_if;
 477         r->id.tcpdiag_cookie[0] = (u32)(unsigned long)req;
 478         r->id.tcpdiag_cookie[1] = (u32)(((unsigned long)req >> 31) >> 1);
 479
 480         tmo = req->expires - jiffies;
 481         if (tmo < 0)
 482                 tmo = 0;
 483
 484         r->id.tcpdiag_sport = inet->sport;
 485         r->id.tcpdiag_dport = req->rmt_port;
 486         r->id.tcpdiag_src[0] = req->af.v4_req.loc_addr;
 487         r->id.tcpdiag_dst[0] = req->af.v4_req.rmt_addr;
 488         r->tcpdiag_expires = jiffies_to_msecs(tmo),
 489         r->tcpdiag_rqueue = 0;
 490         r->tcpdiag_wqueue = 0;
 491         r->tcpdiag_uid = sock_i_uid(sk);
 492         r->tcpdiag_inode = 0;
 493 #ifdef CONFIG_IP_TCPDIAG_IPV6
 494         if (r->tcpdiag_family == AF_INET6) {
 495                 ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_src,
 496                                &req->af.v6_req.loc_addr);
 497                 ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_dst,
 498                                &req->af.v6_req.rmt_addr);
 499         }
 500 #endif
 501         nlh->nlmsg_len = skb->tail - b;
 502
 503         return skb->len;
 504
 505 nlmsg_failure:
 506         skb_trim(skb, b - skb->data);
 507         return -1;
 508 }
 509
 510 static int tcpdiag_dump_reqs(struct sk_buff *skb, struct sock *sk,
 511                              struct netlink_callback *cb)
 512 {
 513         struct tcpdiag_entry entry;
 514         struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
 515         struct tcp_sock *tp = tcp_sk(sk);
 516         struct tcp_listen_opt *lopt;
 517         struct rtattr *bc = NULL;
 518         struct inet_sock *inet = inet_sk(sk);
 519         int j, s_j;
 520         int reqnum, s_reqnum;
 521         int err = 0;
 522
 523         s_j = cb->args[3];
 524         s_reqnum = cb->args[4];
 525
 526         if (s_j > 0)
 527                 s_j--;
 528
 529         entry.family = sk->sk_family;
 530
 531         read_lock_bh(&tp->syn_wait_lock);
 532
 533         lopt = tp->listen_opt;
 534         if (!lopt || !lopt->qlen)
 535                 goto out;
 536
 537         if (cb->nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(*r))) {
 538                 bc = (struct rtattr *)(r + 1);
 539                 entry.sport = inet->num;
 540                 entry.userlocks = sk->sk_userlocks;
 541         }
 542
 543         for (j = s_j; j < TCP_SYNQ_HSIZE; j++) {
 544                 struct open_request *req, *head = lopt->syn_table[j];
 545
 546                 reqnum = 0;
 547                 for (req = head; req; reqnum++, req = req->dl_next) {
 548                         if (reqnum < s_reqnum)
 549                                 continue;
 550                         if (r->id.tcpdiag_dport != req->rmt_port &&
 551                             r->id.tcpdiag_dport)
 552                                 continue;
 553
 554                         if (bc) {
 555                                 entry.saddr =
 556 #ifdef CONFIG_IP_TCPDIAG_IPV6
 557                                         (entry.family == AF_INET6) ?
 558                                         req->af.v6_req.loc_addr.s6_addr32 :
 559 #endif
 560                                         &req->af.v4_req.loc_addr;
 561                                 entry.daddr =
 562 #ifdef CONFIG_IP_TCPDIAG_IPV6
 563                                         (entry.family == AF_INET6) ?
 564                                         req->af.v6_req.rmt_addr.s6_addr32 :
 565 #endif
 566                                         &req->af.v4_req.rmt_addr;
 567                                 entry.dport = ntohs(req->rmt_port);
 568
 569                                 if (!tcpdiag_bc_run(RTA_DATA(bc),
 570                                                     RTA_PAYLOAD(bc), &entry))
 571                                         continue;
 572                         }
 573
 574                         err = tcpdiag_fill_req(skb, sk, req,
 575                                                NETLINK_CB(cb->skb).pid,
 576                                                cb->nlh->nlmsg_seq);
 577                         if (err < 0) {
 578                                 cb->args[3] = j + 1;
 579                                 cb->args[4] = reqnum;
 580                                 goto out;
 581                         }
 582                 }
 583
 584                 s_reqnum = 0;
 585         }
 586
 587 out:
 588         read_unlock_bh(&tp->syn_wait_lock);
 589
 590         return err;
 591 }
 592
 593 static int tcpdiag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 594 {
 595         int i, num;
 596         int s_i, s_num;
 597         struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
 598
 599         s_i = cb->args[1];
 600         s_num = num = cb->args[2];
 601
 602         if (cb->args[0] == 0) {
 603                 if (!(r->tcpdiag_states&(TCPF_LISTEN|TCPF_SYN_RECV)))
 604                         goto skip_listen_ht;
 605                 tcp_listen_lock();
 606                 for (i = s_i; i < TCP_LHTABLE_SIZE; i++) {
 607                         struct sock *sk;
 608                         struct hlist_node *node;
 609
 610                         num = 0;
 611                         sk_for_each(sk, node, &tcp_listening_hash[i]) {
 612                                 struct inet_sock *inet = inet_sk(sk);
 613
 614                                 if (num < s_num) {
 615                                         num++;
 616                                         continue;
 617                                 }
 618
 619                                 if (r->id.tcpdiag_sport != inet->sport &&
 620                                     r->id.tcpdiag_sport)
 621                                         goto next_listen;
 622
 623                                 if (!(r->tcpdiag_states&TCPF_LISTEN) ||
 624                                     r->id.tcpdiag_dport ||
 625                                     cb->args[3] > 0)
 626                                         goto syn_recv;
 627
 628                                 if (tcpdiag_dump_sock(skb, sk, cb) < 0) {
 629                                         tcp_listen_unlock();
 630                                         goto done;
 631                                 }
 632
 633 syn_recv:
 634                                 if (!(r->tcpdiag_states&TCPF_SYN_RECV))
 635                                         goto next_listen;
 636
 637                                 if (tcpdiag_dump_reqs(skb, sk, cb) < 0) {
 638                                         tcp_listen_unlock();
 639                                         goto done;
 640                                 }
 641
 642 next_listen:
 643                                 cb->args[3] = 0;
 644                                 cb->args[4] = 0;
 645                                 ++num;
 646                         }
 647
 648                         s_num = 0;
 649                         cb->args[3] = 0;
 650                         cb->args[4] = 0;
 651                 }
 652                 tcp_listen_unlock();
 653 skip_listen_ht:
 654                 cb->args[0] = 1;
 655                 s_i = num = s_num = 0;
 656         }
 657
 658         if (!(r->tcpdiag_states&~(TCPF_LISTEN|TCPF_SYN_RECV)))
 659                 return skb->len;
 660
 661         for (i = s_i; i < tcp_ehash_size; i++) {
 662                 struct tcp_ehash_bucket *head = &tcp_ehash[i];
 663                 struct sock *sk;
 664                 struct hlist_node *node;
 665
 666                 if (i > s_i)
 667                         s_num = 0;
 668
 669                 read_lock_bh(&head->lock);
 670
 671                 num = 0;
 672                 sk_for_each(sk, node, &head->chain) {
 673                         struct inet_sock *inet = inet_sk(sk);
 674
 675                         if (num < s_num)
 676                                 goto next_normal;
 677                         if (!(r->tcpdiag_states & (1 << sk->sk_state)))
 678                                 goto next_normal;
 679                         if (r->id.tcpdiag_sport != inet->sport &&
 680                             r->id.tcpdiag_sport)
 681                                 goto next_normal;
 682                         if (r->id.tcpdiag_dport != inet->dport && r->id.tcpdiag_dport)
 683                                 goto next_normal;
 684                         if (tcpdiag_dump_sock(skb, sk, cb) < 0) {
 685                                 read_unlock_bh(&head->lock);
 686                                 goto done;
 687                         }
 688 next_normal:
 689                         ++num;
 690                 }
 691
 692                 if (r->tcpdiag_states&TCPF_TIME_WAIT) {
 693                         sk_for_each(sk, node,
 694                                     &tcp_ehash[i + tcp_ehash_size].chain) {
 695                                 struct inet_sock *inet = inet_sk(sk);
 696
 697                                 if (num < s_num)
 698                                         goto next_dying;
 699                                 if (r->id.tcpdiag_sport != inet->sport &&
 700                                     r->id.tcpdiag_sport)
 701                                         goto next_dying;
 702                                 if (r->id.tcpdiag_dport != inet->dport &&
 703                                     r->id.tcpdiag_dport)
 704                                         goto next_dying;
 705                                 if (tcpdiag_dump_sock(skb, sk, cb) < 0) {
 706                                         read_unlock_bh(&head->lock);
 707                                         goto done;
 708                                 }
 709 next_dying:
 710                                 ++num;
 711                         }
 712                 }
 713                 read_unlock_bh(&head->lock);
 714         }
 715
 716 done:
 717         cb->args[1] = i;
 718         cb->args[2] = num;
 719         return skb->len;
 720 }
 721
 722 static int tcpdiag_dump_done(struct netlink_callback *cb)
 723 {
 724         return 0;
 725 }
 726
 727
 728 static __inline__ int
 729 tcpdiag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 730 {
 731         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
 732                 return 0;
 733
 734         if (nlh->nlmsg_type != TCPDIAG_GETSOCK)
 735                 goto err_inval;
 736
 737         if (NLMSG_LENGTH(sizeof(struct tcpdiagreq)) > skb->len)
 738                 goto err_inval;
 739
 740         if (nlh->nlmsg_flags&NLM_F_DUMP) {
 741                 if (nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(struct tcpdiagreq))) {
 742                         struct rtattr *rta = (struct rtattr*)(NLMSG_DATA(nlh) + sizeof(struct tcpdiagreq));
 743                         if (rta->rta_type != TCPDIAG_REQ_BYTECODE ||
 744                             rta->rta_len < 8 ||
 745                             rta->rta_len > nlh->nlmsg_len - NLMSG_SPACE(sizeof(struct tcpdiagreq)))
 746                                 goto err_inval;
 747                         if (tcpdiag_bc_audit(RTA_DATA(rta), RTA_PAYLOAD(rta)))
 748                                 goto err_inval;
 749                 }
 750                 return netlink_dump_start(tcpnl, skb, nlh,
 751                                           tcpdiag_dump,
 752                                           tcpdiag_dump_done);
 753         } else {
 754                 return tcpdiag_get_exact(skb, nlh);
 755         }
 756
 757 err_inval:
 758         return -EINVAL;
 759 }
 760
 761
 762 static inline void tcpdiag_rcv_skb(struct sk_buff *skb)
 763 {
 764         int err;
 765         struct nlmsghdr * nlh;
 766
 767         if (skb->len >= NLMSG_SPACE(0)) {
 768                 nlh = (struct nlmsghdr *)skb->data;
 769                 if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
 770                         return;
 771                 err = tcpdiag_rcv_msg(skb, nlh);
 772                 if (err || nlh->nlmsg_flags & NLM_F_ACK)
 773                         netlink_ack(skb, nlh, err);
 774         }
 775 }
 776
 777 static void tcpdiag_rcv(struct sock *sk, int len)
 778 {
 779         struct sk_buff *skb;
 780
 781         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 782                 tcpdiag_rcv_skb(skb);
 783                 kfree_skb(skb);
 784         }
 785 }
 786
 787 static int __init tcpdiag_init(void)
 788 {
 789         tcpnl = netlink_kernel_create(NETLINK_TCPDIAG, tcpdiag_rcv);
 790         if (tcpnl == NULL)
 791                 return -ENOMEM;
 792         return 0;
 793 }
 794
 795 static void __exit tcpdiag_exit(void)
 796 {
 797         sock_release(tcpnl->sk_socket);
 798 }
 799
 800 module_init(tcpdiag_init);
 801 module_exit(tcpdiag_exit);
 802 MODULE_LICENSE("GPL");