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