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