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 static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
 734                                struct netlink_callback *cb,
 735                                const struct inet_diag_req_v2 *r,
 736                                const struct nlattr *bc)
 737 {
 738         struct inet_connection_sock *icsk = inet_csk(sk);
 739         struct inet_sock *inet = inet_sk(sk);
 740         struct inet_diag_entry entry;
 741         int j, s_j, reqnum, s_reqnum;
 742         struct listen_sock *lopt;
 743         int err = 0;
 744
 745         s_j = cb->args[3];
 746         s_reqnum = cb->args[4];
 747
 748         if (s_j > 0)
 749                 s_j--;
 750
 751         entry.family = sk->sk_family;
 752
 753         spin_lock(&icsk->icsk_accept_queue.syn_wait_lock);
 754
 755         lopt = icsk->icsk_accept_queue.listen_opt;
 756         if (!lopt || !listen_sock_qlen(lopt))
 757                 goto out;
 758
 759         if (bc) {
 760                 entry.sport = inet->inet_num;
 761                 entry.userlocks = sk->sk_userlocks;
 762         }
 763
 764         for (j = s_j; j < lopt->nr_table_entries; j++) {
 765                 struct request_sock *req, *head = lopt->syn_table[j];
 766
 767                 reqnum = 0;
 768                 for (req = head; req; reqnum++, req = req->dl_next) {
 769                         struct inet_request_sock *ireq = inet_rsk(req);
 770
 771                         if (reqnum < s_reqnum)
 772                                 continue;
 773                         if (r->id.idiag_dport != ireq->ir_rmt_port &&
 774                             r->id.idiag_dport)
 775                                 continue;
 776
 777                         if (bc) {
 778                                 /* Note: entry.sport and entry.userlocks are already set */
 779                                 entry_fill_addrs(&entry, req_to_sk(req));
 780                                 entry.dport = ntohs(ireq->ir_rmt_port);
 781
 782                                 if (!inet_diag_bc_run(bc, &entry))
 783                                         continue;
 784                         }
 785
 786                         err = inet_req_diag_fill(req_to_sk(req), skb,
 787                                                  NETLINK_CB(cb->skb).portid,
 788                                                  cb->nlh->nlmsg_seq,
 789                                                  NLM_F_MULTI, cb->nlh);
 790                         if (err < 0) {
 791                                 cb->args[3] = j + 1;
 792                                 cb->args[4] = reqnum;
 793                                 goto out;
 794                         }
 795                 }
 796
 797                 s_reqnum = 0;
 798         }
 799
 800 out:
 801         spin_unlock(&icsk->icsk_accept_queue.syn_wait_lock);
 802
 803         return err;
 804 }
 805
 806 void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
 807                          struct netlink_callback *cb,
 808                          const struct inet_diag_req_v2 *r, struct nlattr *bc)
 809 {
 810         struct net *net = sock_net(skb->sk);
 811         int i, num, s_i, s_num;
 812
 813         s_i = cb->args[1];
 814         s_num = num = cb->args[2];
 815
 816         if (cb->args[0] == 0) {
 817                 if (!(r->idiag_states & (TCPF_LISTEN | TCPF_SYN_RECV)))
 818                         goto skip_listen_ht;
 819
 820                 for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
 821                         struct inet_listen_hashbucket *ilb;
 822                         struct hlist_nulls_node *node;
 823                         struct sock *sk;
 824
 825                         num = 0;
 826                         ilb = &hashinfo->listening_hash[i];
 827                         spin_lock_bh(&ilb->lock);
 828                         sk_nulls_for_each(sk, node, &ilb->head) {
 829                                 struct inet_sock *inet = inet_sk(sk);
 830
 831                                 if (!net_eq(sock_net(sk), net))
 832                                         continue;
 833
 834                                 if (num < s_num) {
 835                                         num++;
 836                                         continue;
 837                                 }
 838
 839                                 if (r->sdiag_family != AF_UNSPEC &&
 840                                     sk->sk_family != r->sdiag_family)
 841                                         goto next_listen;
 842
 843                                 if (r->id.idiag_sport != inet->inet_sport &&
 844                                     r->id.idiag_sport)
 845                                         goto next_listen;
 846
 847                                 if (!(r->idiag_states & TCPF_LISTEN) ||
 848                                     r->id.idiag_dport ||
 849                                     cb->args[3] > 0)
 850                                         goto syn_recv;
 851
 852                                 if (inet_csk_diag_dump(sk, skb, cb, r, bc) < 0) {
 853                                         spin_unlock_bh(&ilb->lock);
 854                                         goto done;
 855                                 }
 856
 857 syn_recv:
 858                                 if (!(r->idiag_states & TCPF_SYN_RECV))
 859                                         goto next_listen;
 860
 861                                 if (inet_diag_dump_reqs(skb, sk, cb, r, bc) < 0) {
 862                                         spin_unlock_bh(&ilb->lock);
 863                                         goto done;
 864                                 }
 865
 866 next_listen:
 867                                 cb->args[3] = 0;
 868                                 cb->args[4] = 0;
 869                                 ++num;
 870                         }
 871                         spin_unlock_bh(&ilb->lock);
 872
 873                         s_num = 0;
 874                         cb->args[3] = 0;
 875                         cb->args[4] = 0;
 876                 }
 877 skip_listen_ht:
 878                 cb->args[0] = 1;
 879                 s_i = num = s_num = 0;
 880         }
 881
 882         if (!(r->idiag_states & ~(TCPF_LISTEN | TCPF_SYN_RECV)))
 883                 goto out;
 884
 885         for (i = s_i; i <= hashinfo->ehash_mask; i++) {
 886                 struct inet_ehash_bucket *head = &hashinfo->ehash[i];
 887                 spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
 888                 struct hlist_nulls_node *node;
 889                 struct sock *sk;
 890
 891                 num = 0;
 892
 893                 if (hlist_nulls_empty(&head->chain))
 894                         continue;
 895
 896                 if (i > s_i)
 897                         s_num = 0;
 898
 899                 spin_lock_bh(lock);
 900                 sk_nulls_for_each(sk, node, &head->chain) {
 901                         int state, res;
 902
 903                         if (!net_eq(sock_net(sk), net))
 904                                 continue;
 905                         if (num < s_num)
 906                                 goto next_normal;
 907                         state = (sk->sk_state == TCP_TIME_WAIT) ?
 908                                 inet_twsk(sk)->tw_substate : sk->sk_state;
 909                         if (!(r->idiag_states & (1 << state)))
 910                                 goto next_normal;
 911                         if (r->sdiag_family != AF_UNSPEC &&
 912                             sk->sk_family != r->sdiag_family)
 913                                 goto next_normal;
 914                         if (r->id.idiag_sport != htons(sk->sk_num) &&
 915                             r->id.idiag_sport)
 916                                 goto next_normal;
 917                         if (r->id.idiag_dport != sk->sk_dport &&
 918                             r->id.idiag_dport)
 919                                 goto next_normal;
 920                         twsk_build_assert();
 921
 922                         if (!inet_diag_bc_sk(bc, sk))
 923                                 goto next_normal;
 924
 925                         res = sk_diag_fill(sk, skb, r,
 926                                            sk_user_ns(NETLINK_CB(cb->skb).sk),
 927                                            NETLINK_CB(cb->skb).portid,
 928                                            cb->nlh->nlmsg_seq, NLM_F_MULTI,
 929                                            cb->nlh);
 930                         if (res < 0) {
 931                                 spin_unlock_bh(lock);
 932                                 goto done;
 933                         }
 934 next_normal:
 935                         ++num;
 936                 }
 937
 938                 spin_unlock_bh(lock);
 939         }
 940
 941 done:
 942         cb->args[1] = i;
 943         cb->args[2] = num;
 944 out:
 945         ;
 946 }
 947 EXPORT_SYMBOL_GPL(inet_diag_dump_icsk);
 948
 949 static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 950                             const struct inet_diag_req_v2 *r,
 951                             struct nlattr *bc)
 952 {
 953         const struct inet_diag_handler *handler;
 954         int err = 0;
 955
 956         handler = inet_diag_lock_handler(r->sdiag_protocol);
 957         if (!IS_ERR(handler))
 958                 handler->dump(skb, cb, r, bc);
 959         else
 960                 err = PTR_ERR(handler);
 961         inet_diag_unlock_handler(handler);
 962
 963         return err ? : skb->len;
 964 }
 965
 966 static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 967 {
 968         int hdrlen = sizeof(struct inet_diag_req_v2);
 969         struct nlattr *bc = NULL;
 970
 971         if (nlmsg_attrlen(cb->nlh, hdrlen))
 972                 bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
 973
 974         return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh), bc);
 975 }
 976
 977 static int inet_diag_type2proto(int type)
 978 {
 979         switch (type) {
 980         case TCPDIAG_GETSOCK:
 981                 return IPPROTO_TCP;
 982         case DCCPDIAG_GETSOCK:
 983                 return IPPROTO_DCCP;
 984         default:
 985                 return 0;
 986         }
 987 }
 988
 989 static int inet_diag_dump_compat(struct sk_buff *skb,
 990                                  struct netlink_callback *cb)
 991 {
 992         struct inet_diag_req *rc = nlmsg_data(cb->nlh);
 993         int hdrlen = sizeof(struct inet_diag_req);
 994         struct inet_diag_req_v2 req;
 995         struct nlattr *bc = NULL;
 996
 997         req.sdiag_family = AF_UNSPEC; /* compatibility */
 998         req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type);
 999         req.idiag_ext = rc->idiag_ext;
1000         req.idiag_states = rc->idiag_states;
1001         req.id = rc->id;
1002
1003         if (nlmsg_attrlen(cb->nlh, hdrlen))
1004                 bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
1005
1006         return __inet_diag_dump(skb, cb, &req, bc);
1007 }
1008
1009 static int inet_diag_get_exact_compat(struct sk_buff *in_skb,
1010                                       const struct nlmsghdr *nlh)
1011 {
1012         struct inet_diag_req *rc = nlmsg_data(nlh);
1013         struct inet_diag_req_v2 req;
1014
1015         req.sdiag_family = rc->idiag_family;
1016         req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type);
1017         req.idiag_ext = rc->idiag_ext;
1018         req.idiag_states = rc->idiag_states;
1019         req.id = rc->id;
1020
1021         return inet_diag_get_exact(in_skb, nlh, &req);
1022 }
1023
1024 static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
1025 {
1026         int hdrlen = sizeof(struct inet_diag_req);
1027         struct net *net = sock_net(skb->sk);
1028
1029         if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX ||
1030             nlmsg_len(nlh) < hdrlen)
1031                 return -EINVAL;
1032
1033         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1034                 if (nlmsg_attrlen(nlh, hdrlen)) {
1035                         struct nlattr *attr;
1036
1037                         attr = nlmsg_find_attr(nlh, hdrlen,
1038                                                INET_DIAG_REQ_BYTECODE);
1039                         if (!attr ||
1040                             nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
1041                             inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
1042                                 return -EINVAL;
1043                 }
1044                 {
1045                         struct netlink_dump_control c = {
1046                                 .dump = inet_diag_dump_compat,
1047                         };
1048                         return netlink_dump_start(net->diag_nlsk, skb, nlh, &c);
1049                 }
1050         }
1051
1052         return inet_diag_get_exact_compat(skb, nlh);
1053 }
1054
1055 static int inet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
1056 {
1057         int hdrlen = sizeof(struct inet_diag_req_v2);
1058         struct net *net = sock_net(skb->sk);
1059
1060         if (nlmsg_len(h) < hdrlen)
1061                 return -EINVAL;
1062
1063         if (h->nlmsg_flags & NLM_F_DUMP) {
1064                 if (nlmsg_attrlen(h, hdrlen)) {
1065                         struct nlattr *attr;
1066
1067                         attr = nlmsg_find_attr(h, hdrlen,
1068                                                INET_DIAG_REQ_BYTECODE);
1069                         if (!attr ||
1070                             nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
1071                             inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
1072                                 return -EINVAL;
1073                 }
1074                 {
1075                         struct netlink_dump_control c = {
1076                                 .dump = inet_diag_dump,
1077                         };
1078                         return netlink_dump_start(net->diag_nlsk, skb, h, &c);
1079                 }
1080         }
1081
1082         return inet_diag_get_exact(skb, h, nlmsg_data(h));
1083 }
1084
1085 static
1086 int inet_diag_handler_get_info(struct sk_buff *skb, struct sock *sk)
1087 {
1088         const struct inet_diag_handler *handler;
1089         struct nlmsghdr *nlh;
1090         struct nlattr *attr;
1091         struct inet_diag_msg *r;
1092         void *info = NULL;
1093         int err = 0;
1094
1095         nlh = nlmsg_put(skb, 0, 0, SOCK_DIAG_BY_FAMILY, sizeof(*r), 0);
1096         if (!nlh)
1097                 return -ENOMEM;
1098
1099         r = nlmsg_data(nlh);
1100         memset(r, 0, sizeof(*r));
1101         inet_diag_msg_common_fill(r, sk);
1102         if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_STREAM)
1103                 r->id.idiag_sport = inet_sk(sk)->inet_sport;
1104         r->idiag_state = sk->sk_state;
1105
1106         if ((err = nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))) {
1107                 nlmsg_cancel(skb, nlh);
1108                 return err;
1109         }
1110
1111         handler = inet_diag_lock_handler(sk->sk_protocol);
1112         if (IS_ERR(handler)) {
1113                 inet_diag_unlock_handler(handler);
1114                 nlmsg_cancel(skb, nlh);
1115                 return PTR_ERR(handler);
1116         }
1117
1118         attr = handler->idiag_info_size
1119                 ? nla_reserve(skb, INET_DIAG_INFO, handler->idiag_info_size)
1120                 : NULL;
1121         if (attr)
1122                 info = nla_data(attr);
1123
1124         handler->idiag_get_info(sk, r, info);
1125         inet_diag_unlock_handler(handler);
1126
1127         nlmsg_end(skb, nlh);
1128         return 0;
1129 }
1130
1131 static const struct sock_diag_handler inet_diag_handler = {
1132         .family = AF_INET,
1133         .dump = inet_diag_handler_dump,
1134         .get_info = inet_diag_handler_get_info,
1135 };
1136
1137 static const struct sock_diag_handler inet6_diag_handler = {
1138         .family = AF_INET6,
1139         .dump = inet_diag_handler_dump,
1140         .get_info = inet_diag_handler_get_info,
1141 };
1142
1143 int inet_diag_register(const struct inet_diag_handler *h)
1144 {
1145         const __u16 type = h->idiag_type;
1146         int err = -EINVAL;
1147
1148         if (type >= IPPROTO_MAX)
1149                 goto out;
1150
1151         mutex_lock(&inet_diag_table_mutex);
1152         err = -EEXIST;
1153         if (!inet_diag_table[type]) {
1154                 inet_diag_table[type] = h;
1155                 err = 0;
1156         }
1157         mutex_unlock(&inet_diag_table_mutex);
1158 out:
1159         return err;
1160 }
1161 EXPORT_SYMBOL_GPL(inet_diag_register);
1162
1163 void inet_diag_unregister(const struct inet_diag_handler *h)
1164 {
1165         const __u16 type = h->idiag_type;
1166
1167         if (type >= IPPROTO_MAX)
1168                 return;
1169
1170         mutex_lock(&inet_diag_table_mutex);
1171         inet_diag_table[type] = NULL;
1172         mutex_unlock(&inet_diag_table_mutex);
1173 }
1174 EXPORT_SYMBOL_GPL(inet_diag_unregister);
1175
1176 static int __init inet_diag_init(void)
1177 {
1178         const int inet_diag_table_size = (IPPROTO_MAX *
1179                                           sizeof(struct inet_diag_handler *));
1180         int err = -ENOMEM;
1181
1182         inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL);
1183         if (!inet_diag_table)
1184                 goto out;
1185
1186         err = sock_diag_register(&inet_diag_handler);
1187         if (err)
1188                 goto out_free_nl;
1189
1190         err = sock_diag_register(&inet6_diag_handler);
1191         if (err)
1192                 goto out_free_inet;
1193
1194         sock_diag_register_inet_compat(inet_diag_rcv_msg_compat);
1195 out:
1196         return err;
1197
1198 out_free_inet:
1199         sock_diag_unregister(&inet_diag_handler);
1200 out_free_nl:
1201         kfree(inet_diag_table);
1202         goto out;
1203 }
1204
1205 static void __exit inet_diag_exit(void)
1206 {
1207         sock_diag_unregister(&inet6_diag_handler);
1208         sock_diag_unregister(&inet_diag_handler);
1209         sock_diag_unregister_inet_compat(inet_diag_rcv_msg_compat);
1210         kfree(inet_diag_table);
1211 }
1212
1213 module_init(inet_diag_init);
1214 module_exit(inet_diag_exit);
1215 MODULE_LICENSE("GPL");
1216 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2 /* AF_INET */);
1217 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10 /* AF_INET6 */);