net/ipv4/ping.c

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              "Ping" sockets
   7  *
   8  *              This program is free software; you can redistribute it and/or
   9  *              modify it under the terms of the GNU General Public License
  10  *              as published by the Free Software Foundation; either version
  11  *              2 of the License, or (at your option) any later version.
  12  *
  13  * Based on ipv4/udp.c code.
  14  *
  15  * Authors:     Vasiliy Kulikov / Openwall (for Linux 2.6),
  16  *              Pavel Kankovsky (for Linux 2.4.32)
  17  *
  18  * Pavel gave all rights to bugs to Vasiliy,
  19  * none of the bugs are Pavel's now.
  20  *
  21  */
  22
  23 #include <linux/uaccess.h>
  24 #include <linux/types.h>
  25 #include <linux/fcntl.h>
  26 #include <linux/socket.h>
  27 #include <linux/sockios.h>
  28 #include <linux/in.h>
  29 #include <linux/errno.h>
  30 #include <linux/timer.h>
  31 #include <linux/mm.h>
  32 #include <linux/inet.h>
  33 #include <linux/netdevice.h>
  34 #include <net/snmp.h>
  35 #include <net/ip.h>
  36 #include <net/icmp.h>
  37 #include <net/protocol.h>
  38 #include <linux/skbuff.h>
  39 #include <linux/proc_fs.h>
  40 #include <linux/export.h>
  41 #include <net/sock.h>
  42 #include <net/ping.h>
  43 #include <net/udp.h>
  44 #include <net/route.h>
  45 #include <net/inet_common.h>
  46 #include <net/checksum.h>
  47
  48 #if IS_ENABLED(CONFIG_IPV6)
  49 #include <linux/in6.h>
  50 #include <linux/icmpv6.h>
  51 #include <net/addrconf.h>
  52 #include <net/ipv6.h>
  53 #include <net/transp_v6.h>
  54 #endif
  55
  56 struct ping_table {
  57         struct hlist_nulls_head hash[PING_HTABLE_SIZE];
  58         rwlock_t                lock;
  59 };
  60
  61 static struct ping_table ping_table;
  62 struct pingv6_ops pingv6_ops;
  63 EXPORT_SYMBOL_GPL(pingv6_ops);
  64
  65 static u16 ping_port_rover;
  66
  67 static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
  68 {
  69         u32 res = (num + net_hash_mix(net)) & mask;
  70
  71         pr_debug("hash(%u) = %u\n", num, res);
  72         return res;
  73 }
  74 EXPORT_SYMBOL_GPL(ping_hash);
  75
  76 static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
  77                                              struct net *net, unsigned int num)
  78 {
  79         return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
  80 }
  81
  82 int ping_get_port(struct sock *sk, unsigned short ident)
  83 {
  84         struct hlist_nulls_node *node;
  85         struct hlist_nulls_head *hlist;
  86         struct inet_sock *isk, *isk2;
  87         struct sock *sk2 = NULL;
  88
  89         isk = inet_sk(sk);
  90         write_lock_bh(&ping_table.lock);
  91         if (ident == 0) {
  92                 u32 i;
  93                 u16 result = ping_port_rover + 1;
  94
  95                 for (i = 0; i < (1L << 16); i++, result++) {
  96                         if (!result)
  97                                 result++; /* avoid zero */
  98                         hlist = ping_hashslot(&ping_table, sock_net(sk),
  99                                             result);
 100                         ping_portaddr_for_each_entry(sk2, node, hlist) {
 101                                 isk2 = inet_sk(sk2);
 102
 103                                 if (isk2->inet_num == result)
 104                                         goto next_port;
 105                         }
 106
 107                         /* found */
 108                         ping_port_rover = ident = result;
 109                         break;
 110 next_port:
 111                         ;
 112                 }
 113                 if (i >= (1L << 16))
 114                         goto fail;
 115         } else {
 116                 hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
 117                 ping_portaddr_for_each_entry(sk2, node, hlist) {
 118                         isk2 = inet_sk(sk2);
 119
 120                         /* BUG? Why is this reuse and not reuseaddr? ping.c
 121                          * doesn't turn off SO_REUSEADDR, and it doesn't expect
 122                          * that other ping processes can steal its packets.
 123                          */
 124                         if ((isk2->inet_num == ident) &&
 125                             (sk2 != sk) &&
 126                             (!sk2->sk_reuse || !sk->sk_reuse))
 127                                 goto fail;
 128                 }
 129         }
 130
 131         pr_debug("found port/ident = %d\n", ident);
 132         isk->inet_num = ident;
 133         if (sk_unhashed(sk)) {
 134                 pr_debug("was not hashed\n");
 135                 sock_hold(sk);
 136                 hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
 137                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 138         }
 139         write_unlock_bh(&ping_table.lock);
 140         return 0;
 141
 142 fail:
 143         write_unlock_bh(&ping_table.lock);
 144         return 1;
 145 }
 146 EXPORT_SYMBOL_GPL(ping_get_port);
 147
 148 int ping_hash(struct sock *sk)
 149 {
 150         pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
 151         BUG(); /* "Please do not press this button again." */
 152
 153         return 0;
 154 }
 155
 156 void ping_unhash(struct sock *sk)
 157 {
 158         struct inet_sock *isk = inet_sk(sk);
 159
 160         pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
 161         write_lock_bh(&ping_table.lock);
 162         if (sk_hashed(sk)) {
 163                 hlist_nulls_del(&sk->sk_nulls_node);
 164                 sk_nulls_node_init(&sk->sk_nulls_node);
 165                 sock_put(sk);
 166                 isk->inet_num = 0;
 167                 isk->inet_sport = 0;
 168                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 169         }
 170         write_unlock_bh(&ping_table.lock);
 171 }
 172 EXPORT_SYMBOL_GPL(ping_unhash);
 173
 174 static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
 175 {
 176         struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
 177         struct sock *sk = NULL;
 178         struct inet_sock *isk;
 179         struct hlist_nulls_node *hnode;
 180         int dif, sdif;
 181
 182         if (skb->protocol == htons(ETH_P_IP)) {
 183                 dif = inet_iif(skb);
 184                 sdif = inet_sdif(skb);
 185                 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
 186                          (int)ident, &ip_hdr(skb)->daddr, dif);
 187 #if IS_ENABLED(CONFIG_IPV6)
 188         } else if (skb->protocol == htons(ETH_P_IPV6)) {
 189                 dif = inet6_iif(skb);
 190                 sdif = inet6_sdif(skb);
 191                 pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
 192                          (int)ident, &ipv6_hdr(skb)->daddr, dif);
 193 #endif
 194         } else {
 195                 return NULL;
 196         }
 197
 198         read_lock_bh(&ping_table.lock);
 199
 200         ping_portaddr_for_each_entry(sk, hnode, hslot) {
 201                 isk = inet_sk(sk);
 202
 203                 pr_debug("iterate\n");
 204                 if (isk->inet_num != ident)
 205                         continue;
 206
 207                 if (skb->protocol == htons(ETH_P_IP) &&
 208                     sk->sk_family == AF_INET) {
 209                         pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
 210                                  (int) isk->inet_num, &isk->inet_rcv_saddr,
 211                                  sk->sk_bound_dev_if);
 212
 213                         if (isk->inet_rcv_saddr &&
 214                             isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
 215                                 continue;
 216 #if IS_ENABLED(CONFIG_IPV6)
 217                 } else if (skb->protocol == htons(ETH_P_IPV6) &&
 218                            sk->sk_family == AF_INET6) {
 219
 220                         pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
 221                                  (int) isk->inet_num,
 222                                  &sk->sk_v6_rcv_saddr,
 223                                  sk->sk_bound_dev_if);
 224
 225                         if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 226                             !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
 227                                              &ipv6_hdr(skb)->daddr))
 228                                 continue;
 229 #endif
 230                 } else {
 231                         continue;
 232                 }
 233
 234                 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif &&
 235                     sk->sk_bound_dev_if != sdif)
 236                         continue;
 237
 238                 sock_hold(sk);
 239                 goto exit;
 240         }
 241
 242         sk = NULL;
 243 exit:
 244         read_unlock_bh(&ping_table.lock);
 245
 246         return sk;
 247 }
 248
 249 static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
 250                                           kgid_t *high)
 251 {
 252         kgid_t *data = net->ipv4.ping_group_range.range;
 253         unsigned int seq;
 254
 255         do {
 256                 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
 257
 258                 *low = data[0];
 259                 *high = data[1];
 260         } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
 261 }
 262
 263
 264 int ping_init_sock(struct sock *sk)
 265 {
 266         struct net *net = sock_net(sk);
 267         kgid_t group = current_egid();
 268         struct group_info *group_info;
 269         int i;
 270         kgid_t low, high;
 271         int ret = 0;
 272
 273         if (sk->sk_family == AF_INET6)
 274                 sk->sk_ipv6only = 1;
 275
 276         inet_get_ping_group_range_net(net, &low, &high);
 277         if (gid_lte(low, group) && gid_lte(group, high))
 278                 return 0;
 279
 280         group_info = get_current_groups();
 281         for (i = 0; i < group_info->ngroups; i++) {
 282                 kgid_t gid = group_info->gid[i];
 283
 284                 if (gid_lte(low, gid) && gid_lte(gid, high))
 285                         goto out_release_group;
 286         }
 287
 288         ret = -EACCES;
 289
 290 out_release_group:
 291         put_group_info(group_info);
 292         return ret;
 293 }
 294 EXPORT_SYMBOL_GPL(ping_init_sock);
 295
 296 void ping_close(struct sock *sk, long timeout)
 297 {
 298         pr_debug("ping_close(sk=%p,sk->num=%u)\n",
 299                  inet_sk(sk), inet_sk(sk)->inet_num);
 300         pr_debug("isk->refcnt = %d\n", refcount_read(&sk->sk_refcnt));
 301
 302         sk_common_release(sk);
 303 }
 304 EXPORT_SYMBOL_GPL(ping_close);
 305
 306 /* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
 307 static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
 308                                 struct sockaddr *uaddr, int addr_len) {
 309         struct net *net = sock_net(sk);
 310         if (sk->sk_family == AF_INET) {
 311                 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
 312                 u32 tb_id = RT_TABLE_LOCAL;
 313                 int chk_addr_ret;
 314
 315                 if (addr_len < sizeof(*addr))
 316                         return -EINVAL;
 317
 318                 if (addr->sin_family != AF_INET &&
 319                     !(addr->sin_family == AF_UNSPEC &&
 320                       addr->sin_addr.s_addr == htonl(INADDR_ANY)))
 321                         return -EAFNOSUPPORT;
 322
 323                 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
 324                          sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
 325
 326                 tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
 327                 chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
 328
 329                 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
 330                         chk_addr_ret = RTN_LOCAL;
 331
 332                 if ((net->ipv4.sysctl_ip_nonlocal_bind == 0 &&
 333                     isk->freebind == 0 && isk->transparent == 0 &&
 334                      chk_addr_ret != RTN_LOCAL) ||
 335                     chk_addr_ret == RTN_MULTICAST ||
 336                     chk_addr_ret == RTN_BROADCAST)
 337                         return -EADDRNOTAVAIL;
 338
 339 #if IS_ENABLED(CONFIG_IPV6)
 340         } else if (sk->sk_family == AF_INET6) {
 341                 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
 342                 int addr_type, scoped, has_addr;
 343                 struct net_device *dev = NULL;
 344
 345                 if (addr_len < sizeof(*addr))
 346                         return -EINVAL;
 347
 348                 if (addr->sin6_family != AF_INET6)
 349                         return -EAFNOSUPPORT;
 350
 351                 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
 352                          sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
 353
 354                 addr_type = ipv6_addr_type(&addr->sin6_addr);
 355                 scoped = __ipv6_addr_needs_scope_id(addr_type);
 356                 if ((addr_type != IPV6_ADDR_ANY &&
 357                      !(addr_type & IPV6_ADDR_UNICAST)) ||
 358                     (scoped && !addr->sin6_scope_id))
 359                         return -EINVAL;
 360
 361                 rcu_read_lock();
 362                 if (addr->sin6_scope_id) {
 363                         dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
 364                         if (!dev) {
 365                                 rcu_read_unlock();
 366                                 return -ENODEV;
 367                         }
 368                 }
 369
 370                 if (!dev && sk->sk_bound_dev_if) {
 371                         dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 372                         if (!dev) {
 373                                 rcu_read_unlock();
 374                                 return -ENODEV;
 375                         }
 376                 }
 377                 has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
 378                                                     scoped);
 379                 rcu_read_unlock();
 380
 381                 if (!(net->ipv6.sysctl.ip_nonlocal_bind ||
 382                       isk->freebind || isk->transparent || has_addr ||
 383                       addr_type == IPV6_ADDR_ANY))
 384                         return -EADDRNOTAVAIL;
 385
 386                 if (scoped)
 387                         sk->sk_bound_dev_if = addr->sin6_scope_id;
 388 #endif
 389         } else {
 390                 return -EAFNOSUPPORT;
 391         }
 392         return 0;
 393 }
 394
 395 static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
 396 {
 397         if (saddr->sa_family == AF_INET) {
 398                 struct inet_sock *isk = inet_sk(sk);
 399                 struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
 400                 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
 401 #if IS_ENABLED(CONFIG_IPV6)
 402         } else if (saddr->sa_family == AF_INET6) {
 403                 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
 404                 struct ipv6_pinfo *np = inet6_sk(sk);
 405                 sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
 406 #endif
 407         }
 408 }
 409
 410 static void ping_clear_saddr(struct sock *sk, int dif)
 411 {
 412         sk->sk_bound_dev_if = dif;
 413         if (sk->sk_family == AF_INET) {
 414                 struct inet_sock *isk = inet_sk(sk);
 415                 isk->inet_rcv_saddr = isk->inet_saddr = 0;
 416 #if IS_ENABLED(CONFIG_IPV6)
 417         } else if (sk->sk_family == AF_INET6) {
 418                 struct ipv6_pinfo *np = inet6_sk(sk);
 419                 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
 420                 memset(&np->saddr, 0, sizeof(np->saddr));
 421 #endif
 422         }
 423 }
 424 /*
 425  * We need our own bind because there are no privileged id's == local ports.
 426  * Moreover, we don't allow binding to multi- and broadcast addresses.
 427  */
 428
 429 int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 430 {
 431         struct inet_sock *isk = inet_sk(sk);
 432         unsigned short snum;
 433         int err;
 434         int dif = sk->sk_bound_dev_if;
 435
 436         err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
 437         if (err)
 438                 return err;
 439
 440         lock_sock(sk);
 441
 442         err = -EINVAL;
 443         if (isk->inet_num != 0)
 444                 goto out;
 445
 446         err = -EADDRINUSE;
 447         ping_set_saddr(sk, uaddr);
 448         snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
 449         if (ping_get_port(sk, snum) != 0) {
 450                 ping_clear_saddr(sk, dif);
 451                 goto out;
 452         }
 453
 454         pr_debug("after bind(): num = %hu, dif = %d\n",
 455                  isk->inet_num,
 456                  sk->sk_bound_dev_if);
 457
 458         err = 0;
 459         if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
 460                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 461 #if IS_ENABLED(CONFIG_IPV6)
 462         if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 463                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 464 #endif
 465
 466         if (snum)
 467                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 468         isk->inet_sport = htons(isk->inet_num);
 469         isk->inet_daddr = 0;
 470         isk->inet_dport = 0;
 471
 472 #if IS_ENABLED(CONFIG_IPV6)
 473         if (sk->sk_family == AF_INET6)
 474                 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
 475 #endif
 476
 477         sk_dst_reset(sk);
 478 out:
 479         release_sock(sk);
 480         pr_debug("ping_v4_bind -> %d\n", err);
 481         return err;
 482 }
 483 EXPORT_SYMBOL_GPL(ping_bind);
 484
 485 /*
 486  * Is this a supported type of ICMP message?
 487  */
 488
 489 static inline int ping_supported(int family, int type, int code)
 490 {
 491         return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
 492                (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
 493 }
 494
 495 /*
 496  * This routine is called by the ICMP module when it gets some
 497  * sort of error condition.
 498  */
 499
 500 void ping_err(struct sk_buff *skb, int offset, u32 info)
 501 {
 502         int family;
 503         struct icmphdr *icmph;
 504         struct inet_sock *inet_sock;
 505         int type;
 506         int code;
 507         struct net *net = dev_net(skb->dev);
 508         struct sock *sk;
 509         int harderr;
 510         int err;
 511
 512         if (skb->protocol == htons(ETH_P_IP)) {
 513                 family = AF_INET;
 514                 type = icmp_hdr(skb)->type;
 515                 code = icmp_hdr(skb)->code;
 516                 icmph = (struct icmphdr *)(skb->data + offset);
 517         } else if (skb->protocol == htons(ETH_P_IPV6)) {
 518                 family = AF_INET6;
 519                 type = icmp6_hdr(skb)->icmp6_type;
 520                 code = icmp6_hdr(skb)->icmp6_code;
 521                 icmph = (struct icmphdr *) (skb->data + offset);
 522         } else {
 523                 BUG();
 524         }
 525
 526         /* We assume the packet has already been checked by icmp_unreach */
 527
 528         if (!ping_supported(family, icmph->type, icmph->code))
 529                 return;
 530
 531         pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
 532                  skb->protocol, type, code, ntohs(icmph->un.echo.id),
 533                  ntohs(icmph->un.echo.sequence));
 534
 535         sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 536         if (!sk) {
 537                 pr_debug("no socket, dropping\n");
 538                 return; /* No socket for error */
 539         }
 540         pr_debug("err on socket %p\n", sk);
 541
 542         err = 0;
 543         harderr = 0;
 544         inet_sock = inet_sk(sk);
 545
 546         if (skb->protocol == htons(ETH_P_IP)) {
 547                 switch (type) {
 548                 default:
 549                 case ICMP_TIME_EXCEEDED:
 550                         err = EHOSTUNREACH;
 551                         break;
 552                 case ICMP_SOURCE_QUENCH:
 553                         /* This is not a real error but ping wants to see it.
 554                          * Report it with some fake errno.
 555                          */
 556                         err = EREMOTEIO;
 557                         break;
 558                 case ICMP_PARAMETERPROB:
 559                         err = EPROTO;
 560                         harderr = 1;
 561                         break;
 562                 case ICMP_DEST_UNREACH:
 563                         if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
 564                                 ipv4_sk_update_pmtu(skb, sk, info);
 565                                 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
 566                                         err = EMSGSIZE;
 567                                         harderr = 1;
 568                                         break;
 569                                 }
 570                                 goto out;
 571                         }
 572                         err = EHOSTUNREACH;
 573                         if (code <= NR_ICMP_UNREACH) {
 574                                 harderr = icmp_err_convert[code].fatal;
 575                                 err = icmp_err_convert[code].errno;
 576                         }
 577                         break;
 578                 case ICMP_REDIRECT:
 579                         /* See ICMP_SOURCE_QUENCH */
 580                         ipv4_sk_redirect(skb, sk);
 581                         err = EREMOTEIO;
 582                         break;
 583                 }
 584 #if IS_ENABLED(CONFIG_IPV6)
 585         } else if (skb->protocol == htons(ETH_P_IPV6)) {
 586                 harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
 587 #endif
 588         }
 589
 590         /*
 591          *      RFC1122: OK.  Passes ICMP errors back to application, as per
 592          *      4.1.3.3.
 593          */
 594         if ((family == AF_INET && !inet_sock->recverr) ||
 595             (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
 596                 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 597                         goto out;
 598         } else {
 599                 if (family == AF_INET) {
 600                         ip_icmp_error(sk, skb, err, 0 /* no remote port */,
 601                                       info, (u8 *)icmph);
 602 #if IS_ENABLED(CONFIG_IPV6)
 603                 } else if (family == AF_INET6) {
 604                         pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
 605                                                    info, (u8 *)icmph);
 606 #endif
 607                 }
 608         }
 609         sk->sk_err = err;
 610         sk->sk_error_report(sk);
 611 out:
 612         sock_put(sk);
 613 }
 614 EXPORT_SYMBOL_GPL(ping_err);
 615
 616 /*
 617  *      Copy and checksum an ICMP Echo packet from user space into a buffer
 618  *      starting from the payload.
 619  */
 620
 621 int ping_getfrag(void *from, char *to,
 622                  int offset, int fraglen, int odd, struct sk_buff *skb)
 623 {
 624         struct pingfakehdr *pfh = (struct pingfakehdr *)from;
 625
 626         if (offset == 0) {
 627                 fraglen -= sizeof(struct icmphdr);
 628                 if (fraglen < 0)
 629                         BUG();
 630                 if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
 631                             fraglen, &pfh->wcheck,
 632                             &pfh->msg->msg_iter))
 633                         return -EFAULT;
 634         } else if (offset < sizeof(struct icmphdr)) {
 635                         BUG();
 636         } else {
 637                 if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
 638                                             &pfh->msg->msg_iter))
 639                         return -EFAULT;
 640         }
 641
 642 #if IS_ENABLED(CONFIG_IPV6)
 643         /* For IPv6, checksum each skb as we go along, as expected by
 644          * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
 645          * wcheck, it will be finalized in ping_v4_push_pending_frames.
 646          */
 647         if (pfh->family == AF_INET6) {
 648                 skb->csum = pfh->wcheck;
 649                 skb->ip_summed = CHECKSUM_NONE;
 650                 pfh->wcheck = 0;
 651         }
 652 #endif
 653
 654         return 0;
 655 }
 656 EXPORT_SYMBOL_GPL(ping_getfrag);
 657
 658 static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
 659                                        struct flowi4 *fl4)
 660 {
 661         struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
 662
 663         if (!skb)
 664                 return 0;
 665         pfh->wcheck = csum_partial((char *)&pfh->icmph,
 666                 sizeof(struct icmphdr), pfh->wcheck);
 667         pfh->icmph.checksum = csum_fold(pfh->wcheck);
 668         memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
 669         skb->ip_summed = CHECKSUM_NONE;
 670         return ip_push_pending_frames(sk, fl4);
 671 }
 672
 673 int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
 674                         void *user_icmph, size_t icmph_len) {
 675         u8 type, code;
 676
 677         if (len > 0xFFFF)
 678                 return -EMSGSIZE;
 679
 680         /* Must have at least a full ICMP header. */
 681         if (len < icmph_len)
 682                 return -EINVAL;
 683
 684         /*
 685          *      Check the flags.
 686          */
 687
 688         /* Mirror BSD error message compatibility */
 689         if (msg->msg_flags & MSG_OOB)
 690                 return -EOPNOTSUPP;
 691
 692         /*
 693          *      Fetch the ICMP header provided by the userland.
 694          *      iovec is modified! The ICMP header is consumed.
 695          */
 696         if (memcpy_from_msg(user_icmph, msg, icmph_len))
 697                 return -EFAULT;
 698
 699         if (family == AF_INET) {
 700                 type = ((struct icmphdr *) user_icmph)->type;
 701                 code = ((struct icmphdr *) user_icmph)->code;
 702 #if IS_ENABLED(CONFIG_IPV6)
 703         } else if (family == AF_INET6) {
 704                 type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
 705                 code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
 706 #endif
 707         } else {
 708                 BUG();
 709         }
 710
 711         if (!ping_supported(family, type, code))
 712                 return -EINVAL;
 713
 714         return 0;
 715 }
 716 EXPORT_SYMBOL_GPL(ping_common_sendmsg);
 717
 718 static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 719 {
 720         struct net *net = sock_net(sk);
 721         struct flowi4 fl4;
 722         struct inet_sock *inet = inet_sk(sk);
 723         struct ipcm_cookie ipc;
 724         struct icmphdr user_icmph;
 725         struct pingfakehdr pfh;
 726         struct rtable *rt = NULL;
 727         struct ip_options_data opt_copy;
 728         int free = 0;
 729         __be32 saddr, daddr, faddr;
 730         u8  tos;
 731         int err;
 732
 733         pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 734
 735         err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
 736                                   sizeof(user_icmph));
 737         if (err)
 738                 return err;
 739
 740         /*
 741          *      Get and verify the address.
 742          */
 743
 744         if (msg->msg_name) {
 745                 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
 746                 if (msg->msg_namelen < sizeof(*usin))
 747                         return -EINVAL;
 748                 if (usin->sin_family != AF_INET)
 749                         return -EAFNOSUPPORT;
 750                 daddr = usin->sin_addr.s_addr;
 751                 /* no remote port */
 752         } else {
 753                 if (sk->sk_state != TCP_ESTABLISHED)
 754                         return -EDESTADDRREQ;
 755                 daddr = inet->inet_daddr;
 756                 /* no remote port */
 757         }
 758
 759         ipc.sockc.tsflags = sk->sk_tsflags;
 760         ipc.addr = inet->inet_saddr;
 761         ipc.opt = NULL;
 762         ipc.oif = sk->sk_bound_dev_if;
 763         ipc.tx_flags = 0;
 764         ipc.ttl = 0;
 765         ipc.tos = -1;
 766
 767         if (msg->msg_controllen) {
 768                 err = ip_cmsg_send(sk, msg, &ipc, false);
 769                 if (unlikely(err)) {
 770                         kfree(ipc.opt);
 771                         return err;
 772                 }
 773                 if (ipc.opt)
 774                         free = 1;
 775         }
 776         if (!ipc.opt) {
 777                 struct ip_options_rcu *inet_opt;
 778
 779                 rcu_read_lock();
 780                 inet_opt = rcu_dereference(inet->inet_opt);
 781                 if (inet_opt) {
 782                         memcpy(&opt_copy, inet_opt,
 783                                sizeof(*inet_opt) + inet_opt->opt.optlen);
 784                         ipc.opt = &opt_copy.opt;
 785                 }
 786                 rcu_read_unlock();
 787         }
 788
 789         sock_tx_timestamp(sk, ipc.sockc.tsflags, &ipc.tx_flags);
 790
 791         saddr = ipc.addr;
 792         ipc.addr = faddr = daddr;
 793
 794         if (ipc.opt && ipc.opt->opt.srr) {
 795                 if (!daddr) {
 796                         err = -EINVAL;
 797                         goto out_free;
 798                 }
 799                 faddr = ipc.opt->opt.faddr;
 800         }
 801         tos = get_rttos(&ipc, inet);
 802         if (sock_flag(sk, SOCK_LOCALROUTE) ||
 803             (msg->msg_flags & MSG_DONTROUTE) ||
 804             (ipc.opt && ipc.opt->opt.is_strictroute)) {
 805                 tos |= RTO_ONLINK;
 806         }
 807
 808         if (ipv4_is_multicast(daddr)) {
 809                 if (!ipc.oif)
 810                         ipc.oif = inet->mc_index;
 811                 if (!saddr)
 812                         saddr = inet->mc_addr;
 813         } else if (!ipc.oif)
 814                 ipc.oif = inet->uc_index;
 815
 816         flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
 817                            RT_SCOPE_UNIVERSE, sk->sk_protocol,
 818                            inet_sk_flowi_flags(sk), faddr, saddr, 0, 0,
 819                            sk->sk_uid);
 820
 821         fl4.fl4_icmp_type = user_icmph.type;
 822         fl4.fl4_icmp_code = user_icmph.code;
 823
 824         security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
 825         rt = ip_route_output_flow(net, &fl4, sk);
 826         if (IS_ERR(rt)) {
 827                 err = PTR_ERR(rt);
 828                 rt = NULL;
 829                 if (err == -ENETUNREACH)
 830                         IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 831                 goto out;
 832         }
 833
 834         err = -EACCES;
 835         if ((rt->rt_flags & RTCF_BROADCAST) &&
 836             !sock_flag(sk, SOCK_BROADCAST))
 837                 goto out;
 838
 839         if (msg->msg_flags & MSG_CONFIRM)
 840                 goto do_confirm;
 841 back_from_confirm:
 842
 843         if (!ipc.addr)
 844                 ipc.addr = fl4.daddr;
 845
 846         lock_sock(sk);
 847
 848         pfh.icmph.type = user_icmph.type; /* already checked */
 849         pfh.icmph.code = user_icmph.code; /* ditto */
 850         pfh.icmph.checksum = 0;
 851         pfh.icmph.un.echo.id = inet->inet_sport;
 852         pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
 853         pfh.msg = msg;
 854         pfh.wcheck = 0;
 855         pfh.family = AF_INET;
 856
 857         err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
 858                         0, &ipc, &rt, msg->msg_flags);
 859         if (err)
 860                 ip_flush_pending_frames(sk);
 861         else
 862                 err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
 863         release_sock(sk);
 864
 865 out:
 866         ip_rt_put(rt);
 867 out_free:
 868         if (free)
 869                 kfree(ipc.opt);
 870         if (!err) {
 871                 icmp_out_count(sock_net(sk), user_icmph.type);
 872                 return len;
 873         }
 874         return err;
 875
 876 do_confirm:
 877         if (msg->msg_flags & MSG_PROBE)
 878                 dst_confirm_neigh(&rt->dst, &fl4.daddr);
 879         if (!(msg->msg_flags & MSG_PROBE) || len)
 880                 goto back_from_confirm;
 881         err = 0;
 882         goto out;
 883 }
 884
 885 int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
 886                  int flags, int *addr_len)
 887 {
 888         struct inet_sock *isk = inet_sk(sk);
 889         int family = sk->sk_family;
 890         struct sk_buff *skb;
 891         int copied, err;
 892
 893         pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
 894
 895         err = -EOPNOTSUPP;
 896         if (flags & MSG_OOB)
 897                 goto out;
 898
 899         if (flags & MSG_ERRQUEUE)
 900                 return inet_recv_error(sk, msg, len, addr_len);
 901
 902         skb = skb_recv_datagram(sk, flags, noblock, &err);
 903         if (!skb)
 904                 goto out;
 905
 906         copied = skb->len;
 907         if (copied > len) {
 908                 msg->msg_flags |= MSG_TRUNC;
 909                 copied = len;
 910         }
 911
 912         /* Don't bother checking the checksum */
 913         err = skb_copy_datagram_msg(skb, 0, msg, copied);
 914         if (err)
 915                 goto done;
 916
 917         sock_recv_timestamp(msg, sk, skb);
 918
 919         /* Copy the address and add cmsg data. */
 920         if (family == AF_INET) {
 921                 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
 922
 923                 if (sin) {
 924                         sin->sin_family = AF_INET;
 925                         sin->sin_port = 0 /* skb->h.uh->source */;
 926                         sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 927                         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 928                         *addr_len = sizeof(*sin);
 929                 }
 930
 931                 if (isk->cmsg_flags)
 932                         ip_cmsg_recv(msg, skb);
 933
 934 #if IS_ENABLED(CONFIG_IPV6)
 935         } else if (family == AF_INET6) {
 936                 struct ipv6_pinfo *np = inet6_sk(sk);
 937                 struct ipv6hdr *ip6 = ipv6_hdr(skb);
 938                 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 939
 940                 if (sin6) {
 941                         sin6->sin6_family = AF_INET6;
 942                         sin6->sin6_port = 0;
 943                         sin6->sin6_addr = ip6->saddr;
 944                         sin6->sin6_flowinfo = 0;
 945                         if (np->sndflow)
 946                                 sin6->sin6_flowinfo = ip6_flowinfo(ip6);
 947                         sin6->sin6_scope_id =
 948                                 ipv6_iface_scope_id(&sin6->sin6_addr,
 949                                                     inet6_iif(skb));
 950                         *addr_len = sizeof(*sin6);
 951                 }
 952
 953                 if (inet6_sk(sk)->rxopt.all)
 954                         pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
 955                 if (skb->protocol == htons(ETH_P_IPV6) &&
 956                     inet6_sk(sk)->rxopt.all)
 957                         pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
 958                 else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
 959                         ip_cmsg_recv(msg, skb);
 960 #endif
 961         } else {
 962                 BUG();
 963         }
 964
 965         err = copied;
 966
 967 done:
 968         skb_free_datagram(sk, skb);
 969 out:
 970         pr_debug("ping_recvmsg -> %d\n", err);
 971         return err;
 972 }
 973 EXPORT_SYMBOL_GPL(ping_recvmsg);
 974
 975 int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 976 {
 977         pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
 978                  inet_sk(sk), inet_sk(sk)->inet_num, skb);
 979         if (sock_queue_rcv_skb(sk, skb) < 0) {
 980                 kfree_skb(skb);
 981                 pr_debug("ping_queue_rcv_skb -> failed\n");
 982                 return -1;
 983         }
 984         return 0;
 985 }
 986 EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
 987
 988
 989 /*
 990  *      All we need to do is get the socket.
 991  */
 992
 993 bool ping_rcv(struct sk_buff *skb)
 994 {
 995         struct sock *sk;
 996         struct net *net = dev_net(skb->dev);
 997         struct icmphdr *icmph = icmp_hdr(skb);
 998         bool rc = false;
 999
1000         /* We assume the packet has already been checked by icmp_rcv */
1001
1002         pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
1003                  skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
1004
1005         /* Push ICMP header back */
1006         skb_push(skb, skb->data - (u8 *)icmph);
1007
1008         sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
1009         if (sk) {
1010                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1011
1012                 pr_debug("rcv on socket %p\n", sk);
1013                 if (skb2 && !ping_queue_rcv_skb(sk, skb2))
1014                         rc = true;
1015                 sock_put(sk);
1016         }
1017
1018         if (!rc)
1019                 pr_debug("no socket, dropping\n");
1020
1021         return rc;
1022 }
1023 EXPORT_SYMBOL_GPL(ping_rcv);
1024
1025 struct proto ping_prot = {
1026         .name =         "PING",
1027         .owner =        THIS_MODULE,
1028         .init =         ping_init_sock,
1029         .close =        ping_close,
1030         .connect =      ip4_datagram_connect,
1031         .disconnect =   __udp_disconnect,
1032         .setsockopt =   ip_setsockopt,
1033         .getsockopt =   ip_getsockopt,
1034         .sendmsg =      ping_v4_sendmsg,
1035         .recvmsg =      ping_recvmsg,
1036         .bind =         ping_bind,
1037         .backlog_rcv =  ping_queue_rcv_skb,
1038         .release_cb =   ip4_datagram_release_cb,
1039         .hash =         ping_hash,
1040         .unhash =       ping_unhash,
1041         .get_port =     ping_get_port,
1042         .obj_size =     sizeof(struct inet_sock),
1043 };
1044 EXPORT_SYMBOL(ping_prot);
1045
1046 #ifdef CONFIG_PROC_FS
1047
1048 static struct sock *ping_get_first(struct seq_file *seq, int start)
1049 {
1050         struct sock *sk;
1051         struct ping_iter_state *state = seq->private;
1052         struct net *net = seq_file_net(seq);
1053
1054         for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1055              ++state->bucket) {
1056                 struct hlist_nulls_node *node;
1057                 struct hlist_nulls_head *hslot;
1058
1059                 hslot = &ping_table.hash[state->bucket];
1060
1061                 if (hlist_nulls_empty(hslot))
1062                         continue;
1063
1064                 sk_nulls_for_each(sk, node, hslot) {
1065                         if (net_eq(sock_net(sk), net) &&
1066                             sk->sk_family == state->family)
1067                                 goto found;
1068                 }
1069         }
1070         sk = NULL;
1071 found:
1072         return sk;
1073 }
1074
1075 static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1076 {
1077         struct ping_iter_state *state = seq->private;
1078         struct net *net = seq_file_net(seq);
1079
1080         do {
1081                 sk = sk_nulls_next(sk);
1082         } while (sk && (!net_eq(sock_net(sk), net)));
1083
1084         if (!sk)
1085                 return ping_get_first(seq, state->bucket + 1);
1086         return sk;
1087 }
1088
1089 static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1090 {
1091         struct sock *sk = ping_get_first(seq, 0);
1092
1093         if (sk)
1094                 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1095                         --pos;
1096         return pos ? NULL : sk;
1097 }
1098
1099 void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1100         __acquires(ping_table.lock)
1101 {
1102         struct ping_iter_state *state = seq->private;
1103         state->bucket = 0;
1104         state->family = family;
1105
1106         read_lock_bh(&ping_table.lock);
1107
1108         return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1109 }
1110 EXPORT_SYMBOL_GPL(ping_seq_start);
1111
1112 static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1113 {
1114         return ping_seq_start(seq, pos, AF_INET);
1115 }
1116
1117 void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1118 {
1119         struct sock *sk;
1120
1121         if (v == SEQ_START_TOKEN)
1122                 sk = ping_get_idx(seq, 0);
1123         else
1124                 sk = ping_get_next(seq, v);
1125
1126         ++*pos;
1127         return sk;
1128 }
1129 EXPORT_SYMBOL_GPL(ping_seq_next);
1130
1131 void ping_seq_stop(struct seq_file *seq, void *v)
1132         __releases(ping_table.lock)
1133 {
1134         read_unlock_bh(&ping_table.lock);
1135 }
1136 EXPORT_SYMBOL_GPL(ping_seq_stop);
1137
1138 static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1139                 int bucket)
1140 {
1141         struct inet_sock *inet = inet_sk(sp);
1142         __be32 dest = inet->inet_daddr;
1143         __be32 src = inet->inet_rcv_saddr;
1144         __u16 destp = ntohs(inet->inet_dport);
1145         __u16 srcp = ntohs(inet->inet_sport);
1146
1147         seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1148                 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1149                 bucket, src, srcp, dest, destp, sp->sk_state,
1150                 sk_wmem_alloc_get(sp),
1151                 sk_rmem_alloc_get(sp),
1152                 0, 0L, 0,
1153                 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1154                 0, sock_i_ino(sp),
1155                 refcount_read(&sp->sk_refcnt), sp,
1156                 atomic_read(&sp->sk_drops));
1157 }
1158
1159 static int ping_v4_seq_show(struct seq_file *seq, void *v)
1160 {
1161         seq_setwidth(seq, 127);
1162         if (v == SEQ_START_TOKEN)
1163                 seq_puts(seq, "  sl  local_address rem_address   st tx_queue "
1164                            "rx_queue tr tm->when retrnsmt   uid  timeout "
1165                            "inode ref pointer drops");
1166         else {
1167                 struct ping_iter_state *state = seq->private;
1168
1169                 ping_v4_format_sock(v, seq, state->bucket);
1170         }
1171         seq_pad(seq, '\n');
1172         return 0;
1173 }
1174
1175 static int ping_seq_open(struct inode *inode, struct file *file)
1176 {
1177         struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1178         return seq_open_net(inode, file, &afinfo->seq_ops,
1179                            sizeof(struct ping_iter_state));
1180 }
1181
1182 const struct file_operations ping_seq_fops = {
1183         .open           = ping_seq_open,
1184         .read           = seq_read,
1185         .llseek         = seq_lseek,
1186         .release        = seq_release_net,
1187 };
1188 EXPORT_SYMBOL_GPL(ping_seq_fops);
1189
1190 static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1191         .name           = "icmp",
1192         .family         = AF_INET,
1193         .seq_fops       = &ping_seq_fops,
1194         .seq_ops        = {
1195                 .start          = ping_v4_seq_start,
1196                 .show           = ping_v4_seq_show,
1197                 .next           = ping_seq_next,
1198                 .stop           = ping_seq_stop,
1199         },
1200 };
1201
1202 int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1203 {
1204         struct proc_dir_entry *p;
1205         p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1206                              afinfo->seq_fops, afinfo);
1207         if (!p)
1208                 return -ENOMEM;
1209         return 0;
1210 }
1211 EXPORT_SYMBOL_GPL(ping_proc_register);
1212
1213 void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1214 {
1215         remove_proc_entry(afinfo->name, net->proc_net);
1216 }
1217 EXPORT_SYMBOL_GPL(ping_proc_unregister);
1218
1219 static int __net_init ping_v4_proc_init_net(struct net *net)
1220 {
1221         return ping_proc_register(net, &ping_v4_seq_afinfo);
1222 }
1223
1224 static void __net_exit ping_v4_proc_exit_net(struct net *net)
1225 {
1226         ping_proc_unregister(net, &ping_v4_seq_afinfo);
1227 }
1228
1229 static struct pernet_operations ping_v4_net_ops = {
1230         .init = ping_v4_proc_init_net,
1231         .exit = ping_v4_proc_exit_net,
1232 };
1233
1234 int __init ping_proc_init(void)
1235 {
1236         return register_pernet_subsys(&ping_v4_net_ops);
1237 }
1238
1239 void ping_proc_exit(void)
1240 {
1241         unregister_pernet_subsys(&ping_v4_net_ops);
1242 }
1243
1244 #endif
1245
1246 void __init ping_init(void)
1247 {
1248         int i;
1249
1250         for (i = 0; i < PING_HTABLE_SIZE; i++)
1251                 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1252         rwlock_init(&ping_table.lock);
1253 }