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