net/ipv4/inet_diag.c

   1 /*
   2  * inet_diag.c  Module for monitoring INET transport protocols sockets.
   3  *
   4  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/fcntl.h>
  16 #include <linux/random.h>
  17 #include <linux/slab.h>
  18 #include <linux/cache.h>
  19 #include <linux/init.h>
  20 #include <linux/time.h>
  21
  22 #include <net/icmp.h>
  23 #include <net/tcp.h>
  24 #include <net/ipv6.h>
  25 #include <net/inet_common.h>
  26 #include <net/inet_connection_sock.h>
  27 #include <net/inet_hashtables.h>
  28 #include <net/inet_timewait_sock.h>
  29 #include <net/inet6_hashtables.h>
  30 #include <net/netlink.h>
  31
  32 #include <linux/inet.h>
  33 #include <linux/stddef.h>
  34
  35 #include <linux/inet_diag.h>
  36 #include <linux/sock_diag.h>
  37
  38 static const struct inet_diag_handler **inet_diag_table;
  39
  40 struct inet_diag_entry {
  41         const __be32 *saddr;
  42         const __be32 *daddr;
  43         u16 sport;
  44         u16 dport;
  45         u16 family;
  46         u16 userlocks;
  47 };
  48
  49 static DEFINE_MUTEX(inet_diag_table_mutex);
  50
  51 static const struct inet_diag_handler *inet_diag_lock_handler(int proto)
  52 {
  53         if (!inet_diag_table[proto])
  54                 request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
  55                                NETLINK_SOCK_DIAG, AF_INET, proto);
  56
  57         mutex_lock(&inet_diag_table_mutex);
  58         if (!inet_diag_table[proto])
  59                 return ERR_PTR(-ENOENT);
  60
  61         return inet_diag_table[proto];
  62 }
  63
  64 static void inet_diag_unlock_handler(const struct inet_diag_handler *handler)
  65 {
  66         mutex_unlock(&inet_diag_table_mutex);
  67 }
  68
  69 void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk)
  70 {
  71         r->idiag_family = sk->sk_family;
  72
  73         r->id.idiag_sport = htons(sk->sk_num);
  74         r->id.idiag_dport = sk->sk_dport;
  75         r->id.idiag_if = sk->sk_bound_dev_if;
  76         sock_diag_save_cookie(sk, r->id.idiag_cookie);
  77
  78 #if IS_ENABLED(CONFIG_IPV6)
  79         if (sk->sk_family == AF_INET6) {
  80                 *(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr;
  81                 *(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr;
  82         } else
  83 #endif
  84         {
  85         memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
  86         memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
  87
  88         r->id.idiag_src[0] = sk->sk_rcv_saddr;
  89         r->id.idiag_dst[0] = sk->sk_daddr;
  90         }
  91 }
  92 EXPORT_SYMBOL_GPL(inet_diag_msg_common_fill);
  93
  94 static size_t inet_sk_attr_size(void)
  95 {
  96         return    nla_total_size(sizeof(struct tcp_info))
  97                 + nla_total_size(1) /* INET_DIAG_SHUTDOWN */
  98                 + nla_total_size(1) /* INET_DIAG_TOS */
  99                 + nla_total_size(1) /* INET_DIAG_TCLASS */
 100                 + nla_total_size(sizeof(struct inet_diag_meminfo))
 101                 + nla_total_size(sizeof(struct inet_diag_msg))
 102                 + nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
 103                 + nla_total_size(TCP_CA_NAME_MAX)
 104                 + nla_total_size(sizeof(struct tcpvegas_info))
 105                 + 64;
 106 }
 107
 108 int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
 109                              struct inet_diag_msg *r, int ext,
 110                              struct user_namespace *user_ns)
 111 {
 112         const struct inet_sock *inet = inet_sk(sk);
 113
 114         if (nla_put_u8(skb, INET_DIAG_SHUTDOWN, sk->sk_shutdown))
 115                 goto errout;
 116
 117         /* IPv6 dual-stack sockets use inet->tos for IPv4 connections,
 118          * hence this needs to be included regardless of socket family.
 119          */
 120         if (ext & (1 << (INET_DIAG_TOS - 1)))
 121                 if (nla_put_u8(skb, INET_DIAG_TOS, inet->tos) < 0)
 122                         goto errout;
 123
 124 #if IS_ENABLED(CONFIG_IPV6)
 125         if (r->idiag_family == AF_INET6) {
 126                 if (ext & (1 << (INET_DIAG_TCLASS - 1)))
 127                         if (nla_put_u8(skb, INET_DIAG_TCLASS,
 128                                        inet6_sk(sk)->tclass) < 0)
 129                                 goto errout;
 130
 131                 if (((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
 132                     nla_put_u8(skb, INET_DIAG_SKV6ONLY, ipv6_only_sock(sk)))
 133                         goto errout;
 134         }
 135 #endif
 136
 137         r->idiag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
 138         r->idiag_inode = sock_i_ino(sk);
 139
 140         return 0;
 141 errout:
 142         return 1;
 143 }
 144 EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill);
 145
 146 int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
 147                       struct sk_buff *skb, const struct inet_diag_req_v2 *req,
 148                       struct user_namespace *user_ns,
 149                       u32 portid, u32 seq, u16 nlmsg_flags,
 150                       const struct nlmsghdr *unlh)
 151 {
 152         const struct tcp_congestion_ops *ca_ops;
 153         const struct inet_diag_handler *handler;
 154         int ext = req->idiag_ext;
 155         struct inet_diag_msg *r;
 156         struct nlmsghdr  *nlh;
 157         struct nlattr *attr;
 158         void *info = NULL;
 159
 160         handler = inet_diag_table[req->sdiag_protocol];
 161         BUG_ON(!handler);
 162
 163         nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
 164                         nlmsg_flags);
 165         if (!nlh)
 166                 return -EMSGSIZE;
 167
 168         r = nlmsg_data(nlh);
 169         BUG_ON(!sk_fullsock(sk));
 170
 171         inet_diag_msg_common_fill(r, sk);
 172         r->idiag_state = sk->sk_state;
 173         r->idiag_timer = 0;
 174         r->idiag_retrans = 0;
 175
 176         if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns))
 177                 goto errout;
 178
 179         if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
 180                 struct inet_diag_meminfo minfo = {
 181                         .idiag_rmem = sk_rmem_alloc_get(sk),
 182                         .idiag_wmem = sk->sk_wmem_queued,
 183                         .idiag_fmem = sk->sk_forward_alloc,
 184                         .idiag_tmem = sk_wmem_alloc_get(sk),
 185                 };
 186
 187                 if (nla_put(skb, INET_DIAG_MEMINFO, sizeof(minfo), &minfo) < 0)
 188                         goto errout;
 189         }
 190
 191         if (ext & (1 << (INET_DIAG_SKMEMINFO - 1)))
 192                 if (sock_diag_put_meminfo(sk, skb, INET_DIAG_SKMEMINFO))
 193                         goto errout;
 194
 195         if (!icsk) {
 196                 handler->idiag_get_info(sk, r, NULL);
 197                 goto out;
 198         }
 199
 200         if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
 201             icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS ||
 202             icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
 203                 r->idiag_timer = 1;
 204                 r->idiag_retrans = icsk->icsk_retransmits;
 205                 r->idiag_expires =
 206                         jiffies_to_msecs(icsk->icsk_timeout - jiffies);
 207         } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
 208                 r->idiag_timer = 4;
 209                 r->idiag_retrans = icsk->icsk_probes_out;
 210                 r->idiag_expires =
 211                         jiffies_to_msecs(icsk->icsk_timeout - jiffies);
 212         } else if (timer_pending(&sk->sk_timer)) {
 213                 r->idiag_timer = 2;
 214                 r->idiag_retrans = icsk->icsk_probes_out;
 215                 r->idiag_expires =
 216                         jiffies_to_msecs(sk->sk_timer.expires - jiffies);
 217         } else {
 218                 r->idiag_timer = 0;
 219                 r->idiag_expires = 0;
 220         }
 221
 222         if ((ext & (1 << (INET_DIAG_INFO - 1))) && handler->idiag_info_size) {
 223                 attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
 224                                          handler->idiag_info_size,
 225                                          INET_DIAG_PAD);
 226                 if (!attr)
 227                         goto errout;
 228
 229                 info = nla_data(attr);
 230         }
 231
 232         if (ext & (1 << (INET_DIAG_CONG - 1))) {
 233                 int err = 0;
 234
 235                 rcu_read_lock();
 236                 ca_ops = READ_ONCE(icsk->icsk_ca_ops);
 237                 if (ca_ops)
 238                         err = nla_put_string(skb, INET_DIAG_CONG, ca_ops->name);
 239                 rcu_read_unlock();
 240                 if (err < 0)
 241                         goto errout;
 242         }
 243
 244         handler->idiag_get_info(sk, r, info);
 245
 246         if (sk->sk_state < TCP_TIME_WAIT) {
 247                 union tcp_cc_info info;
 248                 size_t sz = 0;
 249                 int attr;
 250
 251                 rcu_read_lock();
 252                 ca_ops = READ_ONCE(icsk->icsk_ca_ops);
 253                 if (ca_ops && ca_ops->get_info)
 254                         sz = ca_ops->get_info(sk, ext, &attr, &info);
 255                 rcu_read_unlock();
 256                 if (sz && nla_put(skb, attr, sz, &info) < 0)
 257                         goto errout;
 258         }
 259
 260 out:
 261         nlmsg_end(skb, nlh);
 262         return 0;
 263
 264 errout:
 265         nlmsg_cancel(skb, nlh);
 266         return -EMSGSIZE;
 267 }
 268 EXPORT_SYMBOL_GPL(inet_sk_diag_fill);
 269
 270 static int inet_csk_diag_fill(struct sock *sk,
 271                               struct sk_buff *skb,
 272                               const struct inet_diag_req_v2 *req,
 273                               struct user_namespace *user_ns,
 274                               u32 portid, u32 seq, u16 nlmsg_flags,
 275                               const struct nlmsghdr *unlh)
 276 {
 277         return inet_sk_diag_fill(sk, inet_csk(sk), skb, req,
 278                                  user_ns, portid, seq, nlmsg_flags, unlh);
 279 }
 280
 281 static int inet_twsk_diag_fill(struct sock *sk,
 282                                struct sk_buff *skb,
 283                                u32 portid, u32 seq, u16 nlmsg_flags,
 284                                const struct nlmsghdr *unlh)
 285 {
 286         struct inet_timewait_sock *tw = inet_twsk(sk);
 287         struct inet_diag_msg *r;
 288         struct nlmsghdr *nlh;
 289         long tmo;
 290
 291         nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
 292                         nlmsg_flags);
 293         if (!nlh)
 294                 return -EMSGSIZE;
 295
 296         r = nlmsg_data(nlh);
 297         BUG_ON(tw->tw_state != TCP_TIME_WAIT);
 298
 299         tmo = tw->tw_timer.expires - jiffies;
 300         if (tmo < 0)
 301                 tmo = 0;
 302
 303         inet_diag_msg_common_fill(r, sk);
 304         r->idiag_retrans      = 0;
 305
 306         r->idiag_state        = tw->tw_substate;
 307         r->idiag_timer        = 3;
 308         r->idiag_expires      = jiffies_to_msecs(tmo);
 309         r->idiag_rqueue       = 0;
 310         r->idiag_wqueue       = 0;
 311         r->idiag_uid          = 0;
 312         r->idiag_inode        = 0;
 313
 314         nlmsg_end(skb, nlh);
 315         return 0;
 316 }
 317
 318 static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
 319                               u32 portid, u32 seq, u16 nlmsg_flags,
 320                               const struct nlmsghdr *unlh)
 321 {
 322         struct inet_diag_msg *r;
 323         struct nlmsghdr *nlh;
 324         long tmo;
 325
 326         nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
 327                         nlmsg_flags);
 328         if (!nlh)
 329                 return -EMSGSIZE;
 330
 331         r = nlmsg_data(nlh);
 332         inet_diag_msg_common_fill(r, sk);
 333         r->idiag_state = TCP_SYN_RECV;
 334         r->idiag_timer = 1;
 335         r->idiag_retrans = inet_reqsk(sk)->num_retrans;
 336
 337         BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
 338                      offsetof(struct sock, sk_cookie));
 339
 340         tmo = inet_reqsk(sk)->rsk_timer.expires - jiffies;
 341         r->idiag_expires = (tmo >= 0) ? jiffies_to_msecs(tmo) : 0;
 342         r->idiag_rqueue = 0;
 343         r->idiag_wqueue = 0;
 344         r->idiag_uid    = 0;
 345         r->idiag_inode  = 0;
 346
 347         nlmsg_end(skb, nlh);
 348         return 0;
 349 }
 350
 351 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
 352                         const struct inet_diag_req_v2 *r,
 353                         struct user_namespace *user_ns,
 354                         u32 portid, u32 seq, u16 nlmsg_flags,
 355                         const struct nlmsghdr *unlh)
 356 {
 357         if (sk->sk_state == TCP_TIME_WAIT)
 358                 return inet_twsk_diag_fill(sk, skb, portid, seq,
 359                                            nlmsg_flags, unlh);
 360
 361         if (sk->sk_state == TCP_NEW_SYN_RECV)
 362                 return inet_req_diag_fill(sk, skb, portid, seq,
 363                                           nlmsg_flags, unlh);
 364
 365         return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq,
 366                                   nlmsg_flags, unlh);
 367 }
 368
 369 struct sock *inet_diag_find_one_icsk(struct net *net,
 370                                      struct inet_hashinfo *hashinfo,
 371                                      const struct inet_diag_req_v2 *req)
 372 {
 373         struct sock *sk;
 374
 375         rcu_read_lock();
 376         if (req->sdiag_family == AF_INET)
 377                 sk = inet_lookup(net, hashinfo, NULL, 0, req->id.idiag_dst[0],
 378                                  req->id.idiag_dport, req->id.idiag_src[0],
 379                                  req->id.idiag_sport, req->id.idiag_if);
 380 #if IS_ENABLED(CONFIG_IPV6)
 381         else if (req->sdiag_family == AF_INET6) {
 382                 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
 383                     ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
 384                         sk = inet_lookup(net, hashinfo, NULL, 0, req->id.idiag_dst[3],
 385                                          req->id.idiag_dport, req->id.idiag_src[3],
 386                                          req->id.idiag_sport, req->id.idiag_if);
 387                 else
 388                         sk = inet6_lookup(net, hashinfo, NULL, 0,
 389                                           (struct in6_addr *)req->id.idiag_dst,
 390                                           req->id.idiag_dport,
 391                                           (struct in6_addr *)req->id.idiag_src,
 392                                           req->id.idiag_sport,
 393                                           req->id.idiag_if);
 394         }
 395 #endif
 396         else {
 397                 rcu_read_unlock();
 398                 return ERR_PTR(-EINVAL);
 399         }
 400         rcu_read_unlock();
 401         if (!sk)
 402                 return ERR_PTR(-ENOENT);
 403
 404         if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
 405                 sock_gen_put(sk);
 406                 return ERR_PTR(-ENOENT);
 407         }
 408
 409         return sk;
 410 }
 411 EXPORT_SYMBOL_GPL(inet_diag_find_one_icsk);
 412
 413 int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
 414                             struct sk_buff *in_skb,
 415                             const struct nlmsghdr *nlh,
 416                             const struct inet_diag_req_v2 *req)
 417 {
 418         struct net *net = sock_net(in_skb->sk);
 419         struct sk_buff *rep;
 420         struct sock *sk;
 421         int err;
 422
 423         sk = inet_diag_find_one_icsk(net, hashinfo, req);
 424         if (IS_ERR(sk))
 425                 return PTR_ERR(sk);
 426
 427         rep = nlmsg_new(inet_sk_attr_size(), GFP_KERNEL);
 428         if (!rep) {
 429                 err = -ENOMEM;
 430                 goto out;
 431         }
 432
 433         err = sk_diag_fill(sk, rep, req,
 434                            sk_user_ns(NETLINK_CB(in_skb).sk),
 435                            NETLINK_CB(in_skb).portid,
 436                            nlh->nlmsg_seq, 0, nlh);
 437         if (err < 0) {
 438                 WARN_ON(err == -EMSGSIZE);
 439                 nlmsg_free(rep);
 440                 goto out;
 441         }
 442         err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
 443                               MSG_DONTWAIT);
 444         if (err > 0)
 445                 err = 0;
 446
 447 out:
 448         if (sk)
 449                 sock_gen_put(sk);
 450
 451         return err;
 452 }
 453 EXPORT_SYMBOL_GPL(inet_diag_dump_one_icsk);
 454
 455 static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb,
 456                                const struct nlmsghdr *nlh,
 457                                const struct inet_diag_req_v2 *req)
 458 {
 459         const struct inet_diag_handler *handler;
 460         int err;
 461
 462         handler = inet_diag_lock_handler(req->sdiag_protocol);
 463         if (IS_ERR(handler))
 464                 err = PTR_ERR(handler);
 465         else if (cmd == SOCK_DIAG_BY_FAMILY)
 466                 err = handler->dump_one(in_skb, nlh, req);
 467         else if (cmd == SOCK_DESTROY && handler->destroy)
 468                 err = handler->destroy(in_skb, req);
 469         else
 470                 err = -EOPNOTSUPP;
 471         inet_diag_unlock_handler(handler);
 472
 473         return err;
 474 }
 475
 476 static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits)
 477 {
 478         int words = bits >> 5;
 479
 480         bits &= 0x1f;
 481
 482         if (words) {
 483                 if (memcmp(a1, a2, words << 2))
 484                         return 0;
 485         }
 486         if (bits) {
 487                 __be32 w1, w2;
 488                 __be32 mask;
 489
 490                 w1 = a1[words];
 491                 w2 = a2[words];
 492
 493                 mask = htonl((0xffffffff) << (32 - bits));
 494
 495                 if ((w1 ^ w2) & mask)
 496                         return 0;
 497         }
 498
 499         return 1;
 500 }
 501
 502 static int inet_diag_bc_run(const struct nlattr *_bc,
 503                             const struct inet_diag_entry *entry)
 504 {
 505         const void *bc = nla_data(_bc);
 506         int len = nla_len(_bc);
 507
 508         while (len > 0) {
 509                 int yes = 1;
 510                 const struct inet_diag_bc_op *op = bc;
 511
 512                 switch (op->code) {
 513                 case INET_DIAG_BC_NOP:
 514                         break;
 515                 case INET_DIAG_BC_JMP:
 516                         yes = 0;
 517                         break;
 518                 case INET_DIAG_BC_S_GE:
 519                         yes = entry->sport >= op[1].no;
 520                         break;
 521                 case INET_DIAG_BC_S_LE:
 522                         yes = entry->sport <= op[1].no;
 523                         break;
 524                 case INET_DIAG_BC_D_GE:
 525                         yes = entry->dport >= op[1].no;
 526                         break;
 527                 case INET_DIAG_BC_D_LE:
 528                         yes = entry->dport <= op[1].no;
 529                         break;
 530                 case INET_DIAG_BC_AUTO:
 531                         yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
 532                         break;
 533                 case INET_DIAG_BC_S_COND:
 534                 case INET_DIAG_BC_D_COND: {
 535                         const struct inet_diag_hostcond *cond;
 536                         const __be32 *addr;
 537
 538                         cond = (const struct inet_diag_hostcond *)(op + 1);
 539                         if (cond->port != -1 &&
 540                             cond->port != (op->code == INET_DIAG_BC_S_COND ?
 541                                              entry->sport : entry->dport)) {
 542                                 yes = 0;
 543                                 break;
 544                         }
 545
 546                         if (op->code == INET_DIAG_BC_S_COND)
 547                                 addr = entry->saddr;
 548                         else
 549                                 addr = entry->daddr;
 550
 551                         if (cond->family != AF_UNSPEC &&
 552                             cond->family != entry->family) {
 553                                 if (entry->family == AF_INET6 &&
 554                                     cond->family == AF_INET) {
 555                                         if (addr[0] == 0 && addr[1] == 0 &&
 556                                             addr[2] == htonl(0xffff) &&
 557                                             bitstring_match(addr + 3,
 558                                                             cond->addr,
 559                                                             cond->prefix_len))
 560                                                 break;
 561                                 }
 562                                 yes = 0;
 563                                 break;
 564                         }
 565
 566                         if (cond->prefix_len == 0)
 567                                 break;
 568                         if (bitstring_match(addr, cond->addr,
 569                                             cond->prefix_len))
 570                                 break;
 571                         yes = 0;
 572                         break;
 573                 }
 574                 }
 575
 576                 if (yes) {
 577                         len -= op->yes;
 578                         bc += op->yes;
 579                 } else {
 580                         len -= op->no;
 581                         bc += op->no;
 582                 }
 583         }
 584         return len == 0;
 585 }
 586
 587 /* This helper is available for all sockets (ESTABLISH, TIMEWAIT, SYN_RECV)
 588  */
 589 static void entry_fill_addrs(struct inet_diag_entry *entry,
 590                              const struct sock *sk)
 591 {
 592 #if IS_ENABLED(CONFIG_IPV6)
 593         if (sk->sk_family == AF_INET6) {
 594                 entry->saddr = sk->sk_v6_rcv_saddr.s6_addr32;
 595                 entry->daddr = sk->sk_v6_daddr.s6_addr32;
 596         } else
 597 #endif
 598         {
 599                 entry->saddr = &sk->sk_rcv_saddr;
 600                 entry->daddr = &sk->sk_daddr;
 601         }
 602 }
 603
 604 int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
 605 {
 606         struct inet_sock *inet = inet_sk(sk);
 607         struct inet_diag_entry entry;
 608
 609         if (!bc)
 610                 return 1;
 611
 612         entry.family = sk->sk_family;
 613         entry_fill_addrs(&entry, sk);
 614         entry.sport = inet->inet_num;
 615         entry.dport = ntohs(inet->inet_dport);
 616         entry.userlocks = sk_fullsock(sk) ? sk->sk_userlocks : 0;
 617
 618         return inet_diag_bc_run(bc, &entry);
 619 }
 620 EXPORT_SYMBOL_GPL(inet_diag_bc_sk);
 621
 622 static int valid_cc(const void *bc, int len, int cc)
 623 {
 624         while (len >= 0) {
 625                 const struct inet_diag_bc_op *op = bc;
 626
 627                 if (cc > len)
 628                         return 0;
 629                 if (cc == len)
 630                         return 1;
 631                 if (op->yes < 4 || op->yes & 3)
 632                         return 0;
 633                 len -= op->yes;
 634                 bc  += op->yes;
 635         }
 636         return 0;
 637 }
 638
 639 /* Validate an inet_diag_hostcond. */
 640 static bool valid_hostcond(const struct inet_diag_bc_op *op, int len,
 641                            int *min_len)
 642 {
 643         struct inet_diag_hostcond *cond;
 644         int addr_len;
 645
 646         /* Check hostcond space. */
 647         *min_len += sizeof(struct inet_diag_hostcond);
 648         if (len < *min_len)
 649                 return false;
 650         cond = (struct inet_diag_hostcond *)(op + 1);
 651
 652         /* Check address family and address length. */
 653         switch (cond->family) {
 654         case AF_UNSPEC:
 655                 addr_len = 0;
 656                 break;
 657         case AF_INET:
 658                 addr_len = sizeof(struct in_addr);
 659                 break;
 660         case AF_INET6:
 661                 addr_len = sizeof(struct in6_addr);
 662                 break;
 663         default:
 664                 return false;
 665         }
 666         *min_len += addr_len;
 667         if (len < *min_len)
 668                 return false;
 669
 670         /* Check prefix length (in bits) vs address length (in bytes). */
 671         if (cond->prefix_len > 8 * addr_len)
 672                 return false;
 673
 674         return true;
 675 }
 676
 677 /* Validate a port comparison operator. */
 678 static bool valid_port_comparison(const struct inet_diag_bc_op *op,
 679                                   int len, int *min_len)
 680 {
 681         /* Port comparisons put the port in a follow-on inet_diag_bc_op. */
 682         *min_len += sizeof(struct inet_diag_bc_op);
 683         if (len < *min_len)
 684                 return false;
 685         return true;
 686 }
 687
 688 static int inet_diag_bc_audit(const void *bytecode, int bytecode_len)
 689 {
 690         const void *bc = bytecode;
 691         int  len = bytecode_len;
 692
 693         while (len > 0) {
 694                 int min_len = sizeof(struct inet_diag_bc_op);
 695                 const struct inet_diag_bc_op *op = bc;
 696
 697                 switch (op->code) {
 698                 case INET_DIAG_BC_S_COND:
 699                 case INET_DIAG_BC_D_COND:
 700                         if (!valid_hostcond(bc, len, &min_len))
 701                                 return -EINVAL;
 702                         break;
 703                 case INET_DIAG_BC_S_GE:
 704                 case INET_DIAG_BC_S_LE:
 705                 case INET_DIAG_BC_D_GE:
 706                 case INET_DIAG_BC_D_LE:
 707                         if (!valid_port_comparison(bc, len, &min_len))
 708                                 return -EINVAL;
 709                         break;
 710                 case INET_DIAG_BC_AUTO:
 711                 case INET_DIAG_BC_JMP:
 712                 case INET_DIAG_BC_NOP:
 713                         break;
 714                 default:
 715                         return -EINVAL;
 716                 }
 717
 718                 if (op->code != INET_DIAG_BC_NOP) {
 719                         if (op->no < min_len || op->no > len + 4 || op->no & 3)
 720                                 return -EINVAL;
 721                         if (op->no < len &&
 722                             !valid_cc(bytecode, bytecode_len, len - op->no))
 723                                 return -EINVAL;
 724                 }
 725
 726                 if (op->yes < min_len || op->yes > len + 4 || op->yes & 3)
 727                         return -EINVAL;
 728                 bc  += op->yes;
 729                 len -= op->yes;
 730         }
 731         return len == 0 ? 0 : -EINVAL;
 732 }
 733
 734 static int inet_csk_diag_dump(struct sock *sk,
 735                               struct sk_buff *skb,
 736                               struct netlink_callback *cb,
 737                               const struct inet_diag_req_v2 *r,
 738                               const struct nlattr *bc)
 739 {
 740         if (!inet_diag_bc_sk(bc, sk))
 741                 return 0;
 742
 743         return inet_csk_diag_fill(sk, skb, r,
 744                                   sk_user_ns(NETLINK_CB(cb->skb).sk),
 745                                   NETLINK_CB(cb->skb).portid,
 746                                   cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
 747 }
 748
 749 static void twsk_build_assert(void)
 750 {
 751         BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_family) !=
 752                      offsetof(struct sock, sk_family));
 753
 754         BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_num) !=
 755                      offsetof(struct inet_sock, inet_num));
 756
 757         BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_dport) !=
 758                      offsetof(struct inet_sock, inet_dport));
 759
 760         BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_rcv_saddr) !=
 761                      offsetof(struct inet_sock, inet_rcv_saddr));
 762
 763         BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_daddr) !=
 764                      offsetof(struct inet_sock, inet_daddr));
 765
 766 #if IS_ENABLED(CONFIG_IPV6)
 767         BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_rcv_saddr) !=
 768                      offsetof(struct sock, sk_v6_rcv_saddr));
 769
 770         BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_daddr) !=
 771                      offsetof(struct sock, sk_v6_daddr));
 772 #endif
 773 }
 774
 775 void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
 776                          struct netlink_callback *cb,
 777                          const struct inet_diag_req_v2 *r, struct nlattr *bc)
 778 {
 779         struct net *net = sock_net(skb->sk);
 780         int i, num, s_i, s_num;
 781         u32 idiag_states = r->idiag_states;
 782
 783         if (idiag_states & TCPF_SYN_RECV)
 784                 idiag_states |= TCPF_NEW_SYN_RECV;
 785         s_i = cb->args[1];
 786         s_num = num = cb->args[2];
 787
 788         if (cb->args[0] == 0) {
 789                 if (!(idiag_states & TCPF_LISTEN))
 790                         goto skip_listen_ht;
 791
 792                 for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
 793                         struct inet_listen_hashbucket *ilb;
 794                         struct sock *sk;
 795
 796                         num = 0;
 797                         ilb = &hashinfo->listening_hash[i];
 798                         spin_lock_bh(&ilb->lock);
 799                         sk_for_each(sk, &ilb->head) {
 800                                 struct inet_sock *inet = inet_sk(sk);
 801
 802                                 if (!net_eq(sock_net(sk), net))
 803                                         continue;
 804
 805                                 if (num < s_num) {
 806                                         num++;
 807                                         continue;
 808                                 }
 809
 810                                 if (r->sdiag_family != AF_UNSPEC &&
 811                                     sk->sk_family != r->sdiag_family)
 812                                         goto next_listen;
 813
 814                                 if (r->id.idiag_sport != inet->inet_sport &&
 815                                     r->id.idiag_sport)
 816                                         goto next_listen;
 817
 818                                 if (r->id.idiag_dport ||
 819                                     cb->args[3] > 0)
 820                                         goto next_listen;
 821
 822                                 if (inet_csk_diag_dump(sk, skb, cb, r, bc) < 0) {
 823                                         spin_unlock_bh(&ilb->lock);
 824                                         goto done;
 825                                 }
 826
 827 next_listen:
 828                                 cb->args[3] = 0;
 829                                 cb->args[4] = 0;
 830                                 ++num;
 831                         }
 832                         spin_unlock_bh(&ilb->lock);
 833
 834                         s_num = 0;
 835                         cb->args[3] = 0;
 836                         cb->args[4] = 0;
 837                 }
 838 skip_listen_ht:
 839                 cb->args[0] = 1;
 840                 s_i = num = s_num = 0;
 841         }
 842
 843         if (!(idiag_states & ~TCPF_LISTEN))
 844                 goto out;
 845
 846         for (i = s_i; i <= hashinfo->ehash_mask; i++) {
 847                 struct inet_ehash_bucket *head = &hashinfo->ehash[i];
 848                 spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
 849                 struct hlist_nulls_node *node;
 850                 struct sock *sk;
 851
 852                 num = 0;
 853
 854                 if (hlist_nulls_empty(&head->chain))
 855                         continue;
 856
 857                 if (i > s_i)
 858                         s_num = 0;
 859
 860                 spin_lock_bh(lock);
 861                 sk_nulls_for_each(sk, node, &head->chain) {
 862                         int state, res;
 863
 864                         if (!net_eq(sock_net(sk), net))
 865                                 continue;
 866                         if (num < s_num)
 867                                 goto next_normal;
 868                         state = (sk->sk_state == TCP_TIME_WAIT) ?
 869                                 inet_twsk(sk)->tw_substate : sk->sk_state;
 870                         if (!(idiag_states & (1 << state)))
 871                                 goto next_normal;
 872                         if (r->sdiag_family != AF_UNSPEC &&
 873                             sk->sk_family != r->sdiag_family)
 874                                 goto next_normal;
 875                         if (r->id.idiag_sport != htons(sk->sk_num) &&
 876                             r->id.idiag_sport)
 877                                 goto next_normal;
 878                         if (r->id.idiag_dport != sk->sk_dport &&
 879                             r->id.idiag_dport)
 880                                 goto next_normal;
 881                         twsk_build_assert();
 882
 883                         if (!inet_diag_bc_sk(bc, sk))
 884                                 goto next_normal;
 885
 886                         res = sk_diag_fill(sk, skb, r,
 887                                            sk_user_ns(NETLINK_CB(cb->skb).sk),
 888                                            NETLINK_CB(cb->skb).portid,
 889                                            cb->nlh->nlmsg_seq, NLM_F_MULTI,
 890                                            cb->nlh);
 891                         if (res < 0) {
 892                                 spin_unlock_bh(lock);
 893                                 goto done;
 894                         }
 895 next_normal:
 896                         ++num;
 897                 }
 898
 899                 spin_unlock_bh(lock);
 900                 cond_resched();
 901         }
 902
 903 done:
 904         cb->args[1] = i;
 905         cb->args[2] = num;
 906 out:
 907         ;
 908 }
 909 EXPORT_SYMBOL_GPL(inet_diag_dump_icsk);
 910
 911 static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 912                             const struct inet_diag_req_v2 *r,
 913                             struct nlattr *bc)
 914 {
 915         const struct inet_diag_handler *handler;
 916         int err = 0;
 917
 918         handler = inet_diag_lock_handler(r->sdiag_protocol);
 919         if (!IS_ERR(handler))
 920                 handler->dump(skb, cb, r, bc);
 921         else
 922                 err = PTR_ERR(handler);
 923         inet_diag_unlock_handler(handler);
 924
 925         return err ? : skb->len;
 926 }
 927
 928 static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 929 {
 930         int hdrlen = sizeof(struct inet_diag_req_v2);
 931         struct nlattr *bc = NULL;
 932
 933         if (nlmsg_attrlen(cb->nlh, hdrlen))
 934                 bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
 935
 936         return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh), bc);
 937 }
 938
 939 static int inet_diag_type2proto(int type)
 940 {
 941         switch (type) {
 942         case TCPDIAG_GETSOCK:
 943                 return IPPROTO_TCP;
 944         case DCCPDIAG_GETSOCK:
 945                 return IPPROTO_DCCP;
 946         default:
 947                 return 0;
 948         }
 949 }
 950
 951 static int inet_diag_dump_compat(struct sk_buff *skb,
 952                                  struct netlink_callback *cb)
 953 {
 954         struct inet_diag_req *rc = nlmsg_data(cb->nlh);
 955         int hdrlen = sizeof(struct inet_diag_req);
 956         struct inet_diag_req_v2 req;
 957         struct nlattr *bc = NULL;
 958
 959         req.sdiag_family = AF_UNSPEC; /* compatibility */
 960         req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type);
 961         req.idiag_ext = rc->idiag_ext;
 962         req.idiag_states = rc->idiag_states;
 963         req.id = rc->id;
 964
 965         if (nlmsg_attrlen(cb->nlh, hdrlen))
 966                 bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
 967
 968         return __inet_diag_dump(skb, cb, &req, bc);
 969 }
 970
 971 static int inet_diag_get_exact_compat(struct sk_buff *in_skb,
 972                                       const struct nlmsghdr *nlh)
 973 {
 974         struct inet_diag_req *rc = nlmsg_data(nlh);
 975         struct inet_diag_req_v2 req;
 976
 977         req.sdiag_family = rc->idiag_family;
 978         req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type);
 979         req.idiag_ext = rc->idiag_ext;
 980         req.idiag_states = rc->idiag_states;
 981         req.id = rc->id;
 982
 983         return inet_diag_cmd_exact(SOCK_DIAG_BY_FAMILY, in_skb, nlh, &req);
 984 }
 985
 986 static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
 987 {
 988         int hdrlen = sizeof(struct inet_diag_req);
 989         struct net *net = sock_net(skb->sk);
 990
 991         if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX ||
 992             nlmsg_len(nlh) < hdrlen)
 993                 return -EINVAL;
 994
 995         if (nlh->nlmsg_flags & NLM_F_DUMP) {
 996                 if (nlmsg_attrlen(nlh, hdrlen)) {
 997                         struct nlattr *attr;
 998
 999                         attr = nlmsg_find_attr(nlh, hdrlen,
1000                                                INET_DIAG_REQ_BYTECODE);
1001                         if (!attr ||
1002                             nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
1003                             inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
1004                                 return -EINVAL;
1005                 }
1006                 {
1007                         struct netlink_dump_control c = {
1008                                 .dump = inet_diag_dump_compat,
1009                         };
1010                         return netlink_dump_start(net->diag_nlsk, skb, nlh, &c);
1011                 }
1012         }
1013
1014         return inet_diag_get_exact_compat(skb, nlh);
1015 }
1016
1017 static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h)
1018 {
1019         int hdrlen = sizeof(struct inet_diag_req_v2);
1020         struct net *net = sock_net(skb->sk);
1021
1022         if (nlmsg_len(h) < hdrlen)
1023                 return -EINVAL;
1024
1025         if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY &&
1026             h->nlmsg_flags & NLM_F_DUMP) {
1027                 if (nlmsg_attrlen(h, hdrlen)) {
1028                         struct nlattr *attr;
1029
1030                         attr = nlmsg_find_attr(h, hdrlen,
1031                                                INET_DIAG_REQ_BYTECODE);
1032                         if (!attr ||
1033                             nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
1034                             inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
1035                                 return -EINVAL;
1036                 }
1037                 {
1038                         struct netlink_dump_control c = {
1039                                 .dump = inet_diag_dump,
1040                         };
1041                         return netlink_dump_start(net->diag_nlsk, skb, h, &c);
1042                 }
1043         }
1044
1045         return inet_diag_cmd_exact(h->nlmsg_type, skb, h, nlmsg_data(h));
1046 }
1047
1048 static
1049 int inet_diag_handler_get_info(struct sk_buff *skb, struct sock *sk)
1050 {
1051         const struct inet_diag_handler *handler;
1052         struct nlmsghdr *nlh;
1053         struct nlattr *attr;
1054         struct inet_diag_msg *r;
1055         void *info = NULL;
1056         int err = 0;
1057
1058         nlh = nlmsg_put(skb, 0, 0, SOCK_DIAG_BY_FAMILY, sizeof(*r), 0);
1059         if (!nlh)
1060                 return -ENOMEM;
1061
1062         r = nlmsg_data(nlh);
1063         memset(r, 0, sizeof(*r));
1064         inet_diag_msg_common_fill(r, sk);
1065         if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_STREAM)
1066                 r->id.idiag_sport = inet_sk(sk)->inet_sport;
1067         r->idiag_state = sk->sk_state;
1068
1069         if ((err = nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))) {
1070                 nlmsg_cancel(skb, nlh);
1071                 return err;
1072         }
1073
1074         handler = inet_diag_lock_handler(sk->sk_protocol);
1075         if (IS_ERR(handler)) {
1076                 inet_diag_unlock_handler(handler);
1077                 nlmsg_cancel(skb, nlh);
1078                 return PTR_ERR(handler);
1079         }
1080
1081         attr = handler->idiag_info_size
1082                 ? nla_reserve_64bit(skb, INET_DIAG_INFO,
1083                                     handler->idiag_info_size,
1084                                     INET_DIAG_PAD)
1085                 : NULL;
1086         if (attr)
1087                 info = nla_data(attr);
1088
1089         handler->idiag_get_info(sk, r, info);
1090         inet_diag_unlock_handler(handler);
1091
1092         nlmsg_end(skb, nlh);
1093         return 0;
1094 }
1095
1096 static const struct sock_diag_handler inet_diag_handler = {
1097         .family = AF_INET,
1098         .dump = inet_diag_handler_cmd,
1099         .get_info = inet_diag_handler_get_info,
1100         .destroy = inet_diag_handler_cmd,
1101 };
1102
1103 static const struct sock_diag_handler inet6_diag_handler = {
1104         .family = AF_INET6,
1105         .dump = inet_diag_handler_cmd,
1106         .get_info = inet_diag_handler_get_info,
1107         .destroy = inet_diag_handler_cmd,
1108 };
1109
1110 int inet_diag_register(const struct inet_diag_handler *h)
1111 {
1112         const __u16 type = h->idiag_type;
1113         int err = -EINVAL;
1114
1115         if (type >= IPPROTO_MAX)
1116                 goto out;
1117
1118         mutex_lock(&inet_diag_table_mutex);
1119         err = -EEXIST;
1120         if (!inet_diag_table[type]) {
1121                 inet_diag_table[type] = h;
1122                 err = 0;
1123         }
1124         mutex_unlock(&inet_diag_table_mutex);
1125 out:
1126         return err;
1127 }
1128 EXPORT_SYMBOL_GPL(inet_diag_register);
1129
1130 void inet_diag_unregister(const struct inet_diag_handler *h)
1131 {
1132         const __u16 type = h->idiag_type;
1133
1134         if (type >= IPPROTO_MAX)
1135                 return;
1136
1137         mutex_lock(&inet_diag_table_mutex);
1138         inet_diag_table[type] = NULL;
1139         mutex_unlock(&inet_diag_table_mutex);
1140 }
1141 EXPORT_SYMBOL_GPL(inet_diag_unregister);
1142
1143 static int __init inet_diag_init(void)
1144 {
1145         const int inet_diag_table_size = (IPPROTO_MAX *
1146                                           sizeof(struct inet_diag_handler *));
1147         int err = -ENOMEM;
1148
1149         inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL);
1150         if (!inet_diag_table)
1151                 goto out;
1152
1153         err = sock_diag_register(&inet_diag_handler);
1154         if (err)
1155                 goto out_free_nl;
1156
1157         err = sock_diag_register(&inet6_diag_handler);
1158         if (err)
1159                 goto out_free_inet;
1160
1161         sock_diag_register_inet_compat(inet_diag_rcv_msg_compat);
1162 out:
1163         return err;
1164
1165 out_free_inet:
1166         sock_diag_unregister(&inet_diag_handler);
1167 out_free_nl:
1168         kfree(inet_diag_table);
1169         goto out;
1170 }
1171
1172 static void __exit inet_diag_exit(void)
1173 {
1174         sock_diag_unregister(&inet6_diag_handler);
1175         sock_diag_unregister(&inet_diag_handler);
1176         sock_diag_unregister_inet_compat(inet_diag_rcv_msg_compat);
1177         kfree(inet_diag_table);
1178 }
1179
1180 module_init(inet_diag_init);
1181 module_exit(inet_diag_exit);
1182 MODULE_LICENSE("GPL");
1183 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2 /* AF_INET */);
1184 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10 /* AF_INET6 */);