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