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