net/ipv6/udp.c

   1 /*
   2  *      UDP over IPv6
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      Based on linux/ipv4/udp.c
   9  *
  10  *      $Id: udp.c,v 1.65 2002/02/01 22:01:04 davem Exp $
  11  *
  12  *      Fixes:
  13  *      Hideaki YOSHIFUJI       :       sin6_scope_id support
  14  *      YOSHIFUJI Hideaki @USAGI and:   Support IPV6_V6ONLY socket option, which
  15  *      Alexey Kuznetsov                allow both IPv4 and IPv6 sockets to bind
  16  *                                      a single port at the same time.
  17  *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
  18  *      YOSHIFUJI Hideaki @USAGI:       convert /proc/net/udp6 to seq_file.
  19  *
  20  *      This program is free software; you can redistribute it and/or
  21  *      modify it under the terms of the GNU General Public License
  22  *      as published by the Free Software Foundation; either version
  23  *      2 of the License, or (at your option) any later version.
  24  */
  25
  26 #include <linux/config.h>
  27 #include <linux/errno.h>
  28 #include <linux/types.h>
  29 #include <linux/socket.h>
  30 #include <linux/sockios.h>
  31 #include <linux/sched.h>
  32 #include <linux/net.h>
  33 #include <linux/in6.h>
  34 #include <linux/netdevice.h>
  35 #include <linux/if_arp.h>
  36 #include <linux/ipv6.h>
  37 #include <linux/icmpv6.h>
  38 #include <linux/init.h>
  39 #include <asm/uaccess.h>
  40
  41 #include <net/sock.h>
  42 #include <net/snmp.h>
  43
  44 #include <net/ipv6.h>
  45 #include <net/ndisc.h>
  46 #include <net/protocol.h>
  47 #include <net/transp_v6.h>
  48 #include <net/ip6_route.h>
  49 #include <net/addrconf.h>
  50 #include <net/ip.h>
  51 #include <net/udp.h>
  52 #include <net/raw.h>
  53 #include <net/inet_common.h>
  54 #include <net/tcp_states.h>
  55
  56 #include <net/ip6_checksum.h>
  57 #include <net/xfrm.h>
  58
  59 #include <linux/proc_fs.h>
  60 #include <linux/seq_file.h>
  61
  62 DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6) __read_mostly;
  63
  64 /* Grrr, addr_type already calculated by caller, but I don't want
  65  * to add some silly "cookie" argument to this method just for that.
  66  */
  67 static int udp_v6_get_port(struct sock *sk, unsigned short snum)
  68 {
  69         struct sock *sk2;
  70         struct hlist_node *node;
  71
  72         write_lock_bh(&udp_hash_lock);
  73         if (snum == 0) {
  74                 int best_size_so_far, best, result, i;
  75
  76                 if (udp_port_rover > sysctl_local_port_range[1] ||
  77                     udp_port_rover < sysctl_local_port_range[0])
  78                         udp_port_rover = sysctl_local_port_range[0];
  79                 best_size_so_far = 32767;
  80                 best = result = udp_port_rover;
  81                 for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) {
  82                         int size;
  83                         struct hlist_head *list;
  84
  85                         list = &udp_hash[result & (UDP_HTABLE_SIZE - 1)];
  86                         if (hlist_empty(list)) {
  87                                 if (result > sysctl_local_port_range[1])
  88                                         result = sysctl_local_port_range[0] +
  89                                                 ((result - sysctl_local_port_range[0]) &
  90                                                  (UDP_HTABLE_SIZE - 1));
  91                                 goto gotit;
  92                         }
  93                         size = 0;
  94                         sk_for_each(sk2, node, list)
  95                                 if (++size >= best_size_so_far)
  96                                         goto next;
  97                         best_size_so_far = size;
  98                         best = result;
  99                 next:;
 100                 }
 101                 result = best;
 102                 for(;; result += UDP_HTABLE_SIZE) {
 103                         if (result > sysctl_local_port_range[1])
 104                                 result = sysctl_local_port_range[0]
 105                                         + ((result - sysctl_local_port_range[0]) &
 106                                            (UDP_HTABLE_SIZE - 1));
 107                         if (!udp_lport_inuse(result))
 108                                 break;
 109                 }
 110 gotit:
 111                 udp_port_rover = snum = result;
 112         } else {
 113                 sk_for_each(sk2, node,
 114                             &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]) {
 115                         if (inet_sk(sk2)->num == snum &&
 116                             sk2 != sk &&
 117                             (!sk2->sk_bound_dev_if ||
 118                              !sk->sk_bound_dev_if ||
 119                              sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 120                             (!sk2->sk_reuse || !sk->sk_reuse) &&
 121                             ipv6_rcv_saddr_equal(sk, sk2))
 122                                 goto fail;
 123                 }
 124         }
 125
 126         inet_sk(sk)->num = snum;
 127         if (sk_unhashed(sk)) {
 128                 sk_add_node(sk, &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]);
 129                 sock_prot_inc_use(sk->sk_prot);
 130         }
 131         write_unlock_bh(&udp_hash_lock);
 132         return 0;
 133
 134 fail:
 135         write_unlock_bh(&udp_hash_lock);
 136         return 1;
 137 }
 138
 139 static void udp_v6_hash(struct sock *sk)
 140 {
 141         BUG();
 142 }
 143
 144 static void udp_v6_unhash(struct sock *sk)
 145 {
 146         write_lock_bh(&udp_hash_lock);
 147         if (sk_del_node_init(sk)) {
 148                 inet_sk(sk)->num = 0;
 149                 sock_prot_dec_use(sk->sk_prot);
 150         }
 151         write_unlock_bh(&udp_hash_lock);
 152 }
 153
 154 static struct sock *udp_v6_lookup(struct in6_addr *saddr, u16 sport,
 155                                   struct in6_addr *daddr, u16 dport, int dif)
 156 {
 157         struct sock *sk, *result = NULL;
 158         struct hlist_node *node;
 159         unsigned short hnum = ntohs(dport);
 160         int badness = -1;
 161
 162         read_lock(&udp_hash_lock);
 163         sk_for_each(sk, node, &udp_hash[hnum & (UDP_HTABLE_SIZE - 1)]) {
 164                 struct inet_sock *inet = inet_sk(sk);
 165
 166                 if (inet->num == hnum && sk->sk_family == PF_INET6) {
 167                         struct ipv6_pinfo *np = inet6_sk(sk);
 168                         int score = 0;
 169                         if (inet->dport) {
 170                                 if (inet->dport != sport)
 171                                         continue;
 172                                 score++;
 173                         }
 174                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 175                                 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
 176                                         continue;
 177                                 score++;
 178                         }
 179                         if (!ipv6_addr_any(&np->daddr)) {
 180                                 if (!ipv6_addr_equal(&np->daddr, saddr))
 181                                         continue;
 182                                 score++;
 183                         }
 184                         if (sk->sk_bound_dev_if) {
 185                                 if (sk->sk_bound_dev_if != dif)
 186                                         continue;
 187                                 score++;
 188                         }
 189                         if(score == 4) {
 190                                 result = sk;
 191                                 break;
 192                         } else if(score > badness) {
 193                                 result = sk;
 194                                 badness = score;
 195                         }
 196                 }
 197         }
 198         if (result)
 199                 sock_hold(result);
 200         read_unlock(&udp_hash_lock);
 201         return result;
 202 }
 203
 204 /*
 205  *
 206  */
 207
 208 static void udpv6_close(struct sock *sk, long timeout)
 209 {
 210         sk_common_release(sk);
 211 }
 212
 213 /*
 214  *      This should be easy, if there is something there we
 215  *      return it, otherwise we block.
 216  */
 217
 218 static int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 219                   struct msghdr *msg, size_t len,
 220                   int noblock, int flags, int *addr_len)
 221 {
 222         struct ipv6_pinfo *np = inet6_sk(sk);
 223         struct inet_sock *inet = inet_sk(sk);
 224         struct sk_buff *skb;
 225         size_t copied;
 226         int err;
 227
 228         if (addr_len)
 229                 *addr_len=sizeof(struct sockaddr_in6);
 230
 231         if (flags & MSG_ERRQUEUE)
 232                 return ipv6_recv_error(sk, msg, len);
 233
 234 try_again:
 235         skb = skb_recv_datagram(sk, flags, noblock, &err);
 236         if (!skb)
 237                 goto out;
 238
 239         copied = skb->len - sizeof(struct udphdr);
 240         if (copied > len) {
 241                 copied = len;
 242                 msg->msg_flags |= MSG_TRUNC;
 243         }
 244
 245         if (skb->ip_summed==CHECKSUM_UNNECESSARY) {
 246                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 247                                               copied);
 248         } else if (msg->msg_flags&MSG_TRUNC) {
 249                 if ((unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)))
 250                         goto csum_copy_err;
 251                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 252                                               copied);
 253         } else {
 254                 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 255                 if (err == -EINVAL)
 256                         goto csum_copy_err;
 257         }
 258         if (err)
 259                 goto out_free;
 260
 261         sock_recv_timestamp(msg, sk, skb);
 262
 263         /* Copy the address. */
 264         if (msg->msg_name) {
 265                 struct sockaddr_in6 *sin6;
 266
 267                 sin6 = (struct sockaddr_in6 *) msg->msg_name;
 268                 sin6->sin6_family = AF_INET6;
 269                 sin6->sin6_port = skb->h.uh->source;
 270                 sin6->sin6_flowinfo = 0;
 271                 sin6->sin6_scope_id = 0;
 272
 273                 if (skb->protocol == htons(ETH_P_IP))
 274                         ipv6_addr_set(&sin6->sin6_addr, 0, 0,
 275                                       htonl(0xffff), skb->nh.iph->saddr);
 276                 else {
 277                         ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
 278                         if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 279                                 sin6->sin6_scope_id = IP6CB(skb)->iif;
 280                 }
 281
 282         }
 283         if (skb->protocol == htons(ETH_P_IP)) {
 284                 if (inet->cmsg_flags)
 285                         ip_cmsg_recv(msg, skb);
 286         } else {
 287                 if (np->rxopt.all)
 288                         datagram_recv_ctl(sk, msg, skb);
 289         }
 290
 291         err = copied;
 292         if (flags & MSG_TRUNC)
 293                 err = skb->len - sizeof(struct udphdr);
 294
 295 out_free:
 296         skb_free_datagram(sk, skb);
 297 out:
 298         return err;
 299
 300 csum_copy_err:
 301         /* Clear queue. */
 302         if (flags&MSG_PEEK) {
 303                 int clear = 0;
 304                 spin_lock_bh(&sk->sk_receive_queue.lock);
 305                 if (skb == skb_peek(&sk->sk_receive_queue)) {
 306                         __skb_unlink(skb, &sk->sk_receive_queue);
 307                         clear = 1;
 308                 }
 309                 spin_unlock_bh(&sk->sk_receive_queue.lock);
 310                 if (clear)
 311                         kfree_skb(skb);
 312         }
 313
 314         skb_free_datagram(sk, skb);
 315
 316         if (flags & MSG_DONTWAIT) {
 317                 UDP6_INC_STATS_USER(UDP_MIB_INERRORS);
 318                 return -EAGAIN;
 319         }
 320         goto try_again;
 321 }
 322
 323 static void udpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 324                int type, int code, int offset, __u32 info)
 325 {
 326         struct ipv6_pinfo *np;
 327         struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
 328         struct net_device *dev = skb->dev;
 329         struct in6_addr *saddr = &hdr->saddr;
 330         struct in6_addr *daddr = &hdr->daddr;
 331         struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 332         struct sock *sk;
 333         int err;
 334
 335         sk = udp_v6_lookup(daddr, uh->dest, saddr, uh->source, dev->ifindex);
 336
 337         if (sk == NULL)
 338                 return;
 339
 340         np = inet6_sk(sk);
 341
 342         if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 343                 goto out;
 344
 345         if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 346                 goto out;
 347
 348         if (np->recverr)
 349                 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 350
 351         sk->sk_err = err;
 352         sk->sk_error_report(sk);
 353 out:
 354         sock_put(sk);
 355 }
 356
 357 static inline int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
 358 {
 359         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
 360                 kfree_skb(skb);
 361                 return -1;
 362         }
 363
 364         if (skb->ip_summed != CHECKSUM_UNNECESSARY) {
 365                 if ((unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum))) {
 366                         UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 367                         kfree_skb(skb);
 368                         return 0;
 369                 }
 370                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 371         }
 372
 373         if (sock_queue_rcv_skb(sk,skb)<0) {
 374                 UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 375                 kfree_skb(skb);
 376                 return 0;
 377         }
 378         UDP6_INC_STATS_BH(UDP_MIB_INDATAGRAMS);
 379         return 0;
 380 }
 381
 382 static struct sock *udp_v6_mcast_next(struct sock *sk,
 383                                       u16 loc_port, struct in6_addr *loc_addr,
 384                                       u16 rmt_port, struct in6_addr *rmt_addr,
 385                                       int dif)
 386 {
 387         struct hlist_node *node;
 388         struct sock *s = sk;
 389         unsigned short num = ntohs(loc_port);
 390
 391         sk_for_each_from(s, node) {
 392                 struct inet_sock *inet = inet_sk(s);
 393
 394                 if (inet->num == num && s->sk_family == PF_INET6) {
 395                         struct ipv6_pinfo *np = inet6_sk(s);
 396                         if (inet->dport) {
 397                                 if (inet->dport != rmt_port)
 398                                         continue;
 399                         }
 400                         if (!ipv6_addr_any(&np->daddr) &&
 401                             !ipv6_addr_equal(&np->daddr, rmt_addr))
 402                                 continue;
 403
 404                         if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 405                                 continue;
 406
 407                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 408                                 if (ipv6_addr_equal(&np->rcv_saddr, loc_addr))
 409                                         return s;
 410                                 continue;
 411                         }
 412                         if(!inet6_mc_check(s, loc_addr, rmt_addr))
 413                                 continue;
 414                         return s;
 415                 }
 416         }
 417         return NULL;
 418 }
 419
 420 /*
 421  * Note: called only from the BH handler context,
 422  * so we don't need to lock the hashes.
 423  */
 424 static void udpv6_mcast_deliver(struct udphdr *uh,
 425                                 struct in6_addr *saddr, struct in6_addr *daddr,
 426                                 struct sk_buff *skb)
 427 {
 428         struct sock *sk, *sk2;
 429         int dif;
 430
 431         read_lock(&udp_hash_lock);
 432         sk = sk_head(&udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]);
 433         dif = skb->dev->ifindex;
 434         sk = udp_v6_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif);
 435         if (!sk) {
 436                 kfree_skb(skb);
 437                 goto out;
 438         }
 439
 440         sk2 = sk;
 441         while ((sk2 = udp_v6_mcast_next(sk_next(sk2), uh->dest, daddr,
 442                                         uh->source, saddr, dif))) {
 443                 struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC);
 444                 if (buff)
 445                         udpv6_queue_rcv_skb(sk2, buff);
 446         }
 447         udpv6_queue_rcv_skb(sk, skb);
 448 out:
 449         read_unlock(&udp_hash_lock);
 450 }
 451
 452 static int udpv6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
 453 {
 454         struct sk_buff *skb = *pskb;
 455         struct sock *sk;
 456         struct udphdr *uh;
 457         struct net_device *dev = skb->dev;
 458         struct in6_addr *saddr, *daddr;
 459         u32 ulen = 0;
 460
 461         if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 462                 goto short_packet;
 463
 464         saddr = &skb->nh.ipv6h->saddr;
 465         daddr = &skb->nh.ipv6h->daddr;
 466         uh = skb->h.uh;
 467
 468         ulen = ntohs(uh->len);
 469
 470         /* Check for jumbo payload */
 471         if (ulen == 0)
 472                 ulen = skb->len;
 473
 474         if (ulen > skb->len || ulen < sizeof(*uh))
 475                 goto short_packet;
 476
 477         if (uh->check == 0) {
 478                 /* RFC 2460 section 8.1 says that we SHOULD log
 479                    this error. Well, it is reasonable.
 480                  */
 481                 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
 482                 goto discard;
 483         }
 484
 485         if (ulen < skb->len) {
 486                 if (__pskb_trim(skb, ulen))
 487                         goto discard;
 488                 saddr = &skb->nh.ipv6h->saddr;
 489                 daddr = &skb->nh.ipv6h->daddr;
 490                 uh = skb->h.uh;
 491         }
 492
 493         if (skb->ip_summed==CHECKSUM_HW) {
 494                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 495                 if (csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, skb->csum)) {
 496                         LIMIT_NETDEBUG(KERN_DEBUG "udp v6 hw csum failure.\n");
 497                         skb->ip_summed = CHECKSUM_NONE;
 498                 }
 499         }
 500         if (skb->ip_summed != CHECKSUM_UNNECESSARY)
 501                 skb->csum = ~csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, 0);
 502
 503         /*
 504          *      Multicast receive code
 505          */
 506         if (ipv6_addr_is_multicast(daddr)) {
 507                 udpv6_mcast_deliver(uh, saddr, daddr, skb);
 508                 return 0;
 509         }
 510
 511         /* Unicast */
 512
 513         /*
 514          * check socket cache ... must talk to Alan about his plans
 515          * for sock caches... i'll skip this for now.
 516          */
 517         sk = udp_v6_lookup(saddr, uh->source, daddr, uh->dest, dev->ifindex);
 518
 519         if (sk == NULL) {
 520                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 521                         goto discard;
 522
 523                 if (skb->ip_summed != CHECKSUM_UNNECESSARY &&
 524                     (unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)))
 525                         goto discard;
 526                 UDP6_INC_STATS_BH(UDP_MIB_NOPORTS);
 527
 528                 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0, dev);
 529
 530                 kfree_skb(skb);
 531                 return(0);
 532         }
 533
 534         /* deliver */
 535
 536         udpv6_queue_rcv_skb(sk, skb);
 537         sock_put(sk);
 538         return(0);
 539
 540 short_packet:
 541         if (net_ratelimit())
 542                 printk(KERN_DEBUG "UDP: short packet: %d/%u\n", ulen, skb->len);
 543
 544 discard:
 545         UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 546         kfree_skb(skb);
 547         return(0);
 548 }
 549 /*
 550  * Throw away all pending data and cancel the corking. Socket is locked.
 551  */
 552 static void udp_v6_flush_pending_frames(struct sock *sk)
 553 {
 554         struct udp_sock *up = udp_sk(sk);
 555
 556         if (up->pending) {
 557                 up->len = 0;
 558                 up->pending = 0;
 559                 ip6_flush_pending_frames(sk);
 560         }
 561 }
 562
 563 /*
 564  *      Sending
 565  */
 566
 567 static int udp_v6_push_pending_frames(struct sock *sk, struct udp_sock *up)
 568 {
 569         struct sk_buff *skb;
 570         struct udphdr *uh;
 571         struct inet_sock *inet = inet_sk(sk);
 572         struct flowi *fl = &inet->cork.fl;
 573         int err = 0;
 574
 575         /* Grab the skbuff where UDP header space exists. */
 576         if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 577                 goto out;
 578
 579         /*
 580          * Create a UDP header
 581          */
 582         uh = skb->h.uh;
 583         uh->source = fl->fl_ip_sport;
 584         uh->dest = fl->fl_ip_dport;
 585         uh->len = htons(up->len);
 586         uh->check = 0;
 587
 588         if (sk->sk_no_check == UDP_CSUM_NOXMIT) {
 589                 skb->ip_summed = CHECKSUM_NONE;
 590                 goto send;
 591         }
 592
 593         if (skb_queue_len(&sk->sk_write_queue) == 1) {
 594                 skb->csum = csum_partial((char *)uh,
 595                                 sizeof(struct udphdr), skb->csum);
 596                 uh->check = csum_ipv6_magic(&fl->fl6_src,
 597                                             &fl->fl6_dst,
 598                                             up->len, fl->proto, skb->csum);
 599         } else {
 600                 u32 tmp_csum = 0;
 601
 602                 skb_queue_walk(&sk->sk_write_queue, skb) {
 603                         tmp_csum = csum_add(tmp_csum, skb->csum);
 604                 }
 605                 tmp_csum = csum_partial((char *)uh,
 606                                 sizeof(struct udphdr), tmp_csum);
 607                 tmp_csum = csum_ipv6_magic(&fl->fl6_src,
 608                                            &fl->fl6_dst,
 609                                            up->len, fl->proto, tmp_csum);
 610                 uh->check = tmp_csum;
 611
 612         }
 613         if (uh->check == 0)
 614                 uh->check = -1;
 615
 616 send:
 617         err = ip6_push_pending_frames(sk);
 618 out:
 619         up->len = 0;
 620         up->pending = 0;
 621         return err;
 622 }
 623
 624 static int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 625                   struct msghdr *msg, size_t len)
 626 {
 627         struct ipv6_txoptions opt_space;
 628         struct udp_sock *up = udp_sk(sk);
 629         struct inet_sock *inet = inet_sk(sk);
 630         struct ipv6_pinfo *np = inet6_sk(sk);
 631         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
 632         struct in6_addr *daddr, *final_p = NULL, final;
 633         struct ipv6_txoptions *opt = NULL;
 634         struct ip6_flowlabel *flowlabel = NULL;
 635         struct flowi *fl = &inet->cork.fl;
 636         struct dst_entry *dst;
 637         int addr_len = msg->msg_namelen;
 638         int ulen = len;
 639         int hlimit = -1;
 640         int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
 641         int err;
 642
 643         /* destination address check */
 644         if (sin6) {
 645                 if (addr_len < offsetof(struct sockaddr, sa_data))
 646                         return -EINVAL;
 647
 648                 switch (sin6->sin6_family) {
 649                 case AF_INET6:
 650                         if (addr_len < SIN6_LEN_RFC2133)
 651                                 return -EINVAL;
 652                         daddr = &sin6->sin6_addr;
 653                         break;
 654                 case AF_INET:
 655                         goto do_udp_sendmsg;
 656                 case AF_UNSPEC:
 657                         msg->msg_name = sin6 = NULL;
 658                         msg->msg_namelen = addr_len = 0;
 659                         daddr = NULL;
 660                         break;
 661                 default:
 662                         return -EINVAL;
 663                 }
 664         } else if (!up->pending) {
 665                 if (sk->sk_state != TCP_ESTABLISHED)
 666                         return -EDESTADDRREQ;
 667                 daddr = &np->daddr;
 668         } else
 669                 daddr = NULL;
 670
 671         if (daddr) {
 672                 if (ipv6_addr_type(daddr) == IPV6_ADDR_MAPPED) {
 673                         struct sockaddr_in sin;
 674                         sin.sin_family = AF_INET;
 675                         sin.sin_port = sin6 ? sin6->sin6_port : inet->dport;
 676                         sin.sin_addr.s_addr = daddr->s6_addr32[3];
 677                         msg->msg_name = &sin;
 678                         msg->msg_namelen = sizeof(sin);
 679 do_udp_sendmsg:
 680                         if (__ipv6_only_sock(sk))
 681                                 return -ENETUNREACH;
 682                         return udp_sendmsg(iocb, sk, msg, len);
 683                 }
 684         }
 685
 686         if (up->pending == AF_INET)
 687                 return udp_sendmsg(iocb, sk, msg, len);
 688
 689         /* Rough check on arithmetic overflow,
 690            better check is made in ip6_build_xmit
 691            */
 692         if (len > INT_MAX - sizeof(struct udphdr))
 693                 return -EMSGSIZE;
 694
 695         if (up->pending) {
 696                 /*
 697                  * There are pending frames.
 698                  * The socket lock must be held while it's corked.
 699                  */
 700                 lock_sock(sk);
 701                 if (likely(up->pending)) {
 702                         if (unlikely(up->pending != AF_INET6)) {
 703                                 release_sock(sk);
 704                                 return -EAFNOSUPPORT;
 705                         }
 706                         dst = NULL;
 707                         goto do_append_data;
 708                 }
 709                 release_sock(sk);
 710         }
 711         ulen += sizeof(struct udphdr);
 712
 713         memset(fl, 0, sizeof(*fl));
 714
 715         if (sin6) {
 716                 if (sin6->sin6_port == 0)
 717                         return -EINVAL;
 718
 719                 fl->fl_ip_dport = sin6->sin6_port;
 720                 daddr = &sin6->sin6_addr;
 721
 722                 if (np->sndflow) {
 723                         fl->fl6_flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
 724                         if (fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
 725                                 flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 726                                 if (flowlabel == NULL)
 727                                         return -EINVAL;
 728                                 daddr = &flowlabel->dst;
 729                         }
 730                 }
 731
 732                 /*
 733                  * Otherwise it will be difficult to maintain
 734                  * sk->sk_dst_cache.
 735                  */
 736                 if (sk->sk_state == TCP_ESTABLISHED &&
 737                     ipv6_addr_equal(daddr, &np->daddr))
 738                         daddr = &np->daddr;
 739
 740                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 741                     sin6->sin6_scope_id &&
 742                     ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
 743                         fl->oif = sin6->sin6_scope_id;
 744         } else {
 745                 if (sk->sk_state != TCP_ESTABLISHED)
 746                         return -EDESTADDRREQ;
 747
 748                 fl->fl_ip_dport = inet->dport;
 749                 daddr = &np->daddr;
 750                 fl->fl6_flowlabel = np->flow_label;
 751         }
 752
 753         if (!fl->oif)
 754                 fl->oif = sk->sk_bound_dev_if;
 755
 756         if (msg->msg_controllen) {
 757                 opt = &opt_space;
 758                 memset(opt, 0, sizeof(struct ipv6_txoptions));
 759                 opt->tot_len = sizeof(*opt);
 760
 761                 err = datagram_send_ctl(msg, fl, opt, &hlimit);
 762                 if (err < 0) {
 763                         fl6_sock_release(flowlabel);
 764                         return err;
 765                 }
 766                 if ((fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
 767                         flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 768                         if (flowlabel == NULL)
 769                                 return -EINVAL;
 770                 }
 771                 if (!(opt->opt_nflen|opt->opt_flen))
 772                         opt = NULL;
 773         }
 774         if (opt == NULL)
 775                 opt = np->opt;
 776         opt = fl6_merge_options(&opt_space, flowlabel, opt);
 777
 778         fl->proto = IPPROTO_UDP;
 779         ipv6_addr_copy(&fl->fl6_dst, daddr);
 780         if (ipv6_addr_any(&fl->fl6_src) && !ipv6_addr_any(&np->saddr))
 781                 ipv6_addr_copy(&fl->fl6_src, &np->saddr);
 782         fl->fl_ip_sport = inet->sport;
 783
 784         /* merge ip6_build_xmit from ip6_output */
 785         if (opt && opt->srcrt) {
 786                 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
 787                 ipv6_addr_copy(&final, &fl->fl6_dst);
 788                 ipv6_addr_copy(&fl->fl6_dst, rt0->addr);
 789                 final_p = &final;
 790         }
 791
 792         if (!fl->oif && ipv6_addr_is_multicast(&fl->fl6_dst))
 793                 fl->oif = np->mcast_oif;
 794
 795         err = ip6_dst_lookup(sk, &dst, fl);
 796         if (err)
 797                 goto out;
 798         if (final_p)
 799                 ipv6_addr_copy(&fl->fl6_dst, final_p);
 800
 801         if ((err = xfrm_lookup(&dst, fl, sk, 0)) < 0) {
 802                 dst_release(dst);
 803                 goto out;
 804         }
 805
 806         if (hlimit < 0) {
 807                 if (ipv6_addr_is_multicast(&fl->fl6_dst))
 808                         hlimit = np->mcast_hops;
 809                 else
 810                         hlimit = np->hop_limit;
 811                 if (hlimit < 0)
 812                         hlimit = dst_metric(dst, RTAX_HOPLIMIT);
 813                 if (hlimit < 0)
 814                         hlimit = ipv6_get_hoplimit(dst->dev);
 815         }
 816
 817         if (msg->msg_flags&MSG_CONFIRM)
 818                 goto do_confirm;
 819 back_from_confirm:
 820
 821         lock_sock(sk);
 822         if (unlikely(up->pending)) {
 823                 /* The socket is already corked while preparing it. */
 824                 /* ... which is an evident application bug. --ANK */
 825                 release_sock(sk);
 826
 827                 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
 828                 err = -EINVAL;
 829                 goto out;
 830         }
 831
 832         up->pending = AF_INET6;
 833
 834 do_append_data:
 835         up->len += ulen;
 836         err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov, ulen, sizeof(struct udphdr),
 837                               hlimit, opt, fl, (struct rt6_info*)dst,
 838                               corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 839         if (err)
 840                 udp_v6_flush_pending_frames(sk);
 841         else if (!corkreq)
 842                 err = udp_v6_push_pending_frames(sk, up);
 843
 844         if (dst)
 845                 ip6_dst_store(sk, dst,
 846                               ipv6_addr_equal(&fl->fl6_dst, &np->daddr) ?
 847                               &np->daddr : NULL);
 848         if (err > 0)
 849                 err = np->recverr ? net_xmit_errno(err) : 0;
 850         release_sock(sk);
 851 out:
 852         fl6_sock_release(flowlabel);
 853         if (!err) {
 854                 UDP6_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS);
 855                 return len;
 856         }
 857         return err;
 858
 859 do_confirm:
 860         dst_confirm(dst);
 861         if (!(msg->msg_flags&MSG_PROBE) || len)
 862                 goto back_from_confirm;
 863         err = 0;
 864         goto out;
 865 }
 866
 867 static int udpv6_destroy_sock(struct sock *sk)
 868 {
 869         lock_sock(sk);
 870         udp_v6_flush_pending_frames(sk);
 871         release_sock(sk);
 872
 873         inet6_destroy_sock(sk);
 874
 875         return 0;
 876 }
 877
 878 /*
 879  *      Socket option code for UDP
 880  */
 881 static int udpv6_setsockopt(struct sock *sk, int level, int optname,
 882                           char __user *optval, int optlen)
 883 {
 884         struct udp_sock *up = udp_sk(sk);
 885         int val;
 886         int err = 0;
 887
 888         if (level != SOL_UDP)
 889                 return ipv6_setsockopt(sk, level, optname, optval, optlen);
 890
 891         if(optlen<sizeof(int))
 892                 return -EINVAL;
 893
 894         if (get_user(val, (int __user *)optval))
 895                 return -EFAULT;
 896
 897         switch(optname) {
 898         case UDP_CORK:
 899                 if (val != 0) {
 900                         up->corkflag = 1;
 901                 } else {
 902                         up->corkflag = 0;
 903                         lock_sock(sk);
 904                         udp_v6_push_pending_frames(sk, up);
 905                         release_sock(sk);
 906                 }
 907                 break;
 908
 909         case UDP_ENCAP:
 910                 switch (val) {
 911                 case 0:
 912                         up->encap_type = val;
 913                         break;
 914                 default:
 915                         err = -ENOPROTOOPT;
 916                         break;
 917                 }
 918                 break;
 919
 920         default:
 921                 err = -ENOPROTOOPT;
 922                 break;
 923         };
 924
 925         return err;
 926 }
 927
 928 static int udpv6_getsockopt(struct sock *sk, int level, int optname,
 929                           char __user *optval, int __user *optlen)
 930 {
 931         struct udp_sock *up = udp_sk(sk);
 932         int val, len;
 933
 934         if (level != SOL_UDP)
 935                 return ipv6_getsockopt(sk, level, optname, optval, optlen);
 936
 937         if(get_user(len,optlen))
 938                 return -EFAULT;
 939
 940         len = min_t(unsigned int, len, sizeof(int));
 941
 942         if(len < 0)
 943                 return -EINVAL;
 944
 945         switch(optname) {
 946         case UDP_CORK:
 947                 val = up->corkflag;
 948                 break;
 949
 950         case UDP_ENCAP:
 951                 val = up->encap_type;
 952                 break;
 953
 954         default:
 955                 return -ENOPROTOOPT;
 956         };
 957
 958         if(put_user(len, optlen))
 959                 return -EFAULT;
 960         if(copy_to_user(optval, &val,len))
 961                 return -EFAULT;
 962         return 0;
 963 }
 964
 965 static struct inet6_protocol udpv6_protocol = {
 966         .handler        =       udpv6_rcv,
 967         .err_handler    =       udpv6_err,
 968         .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
 969 };
 970
 971 /* ------------------------------------------------------------------------ */
 972 #ifdef CONFIG_PROC_FS
 973
 974 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
 975 {
 976         struct inet_sock *inet = inet_sk(sp);
 977         struct ipv6_pinfo *np = inet6_sk(sp);
 978         struct in6_addr *dest, *src;
 979         __u16 destp, srcp;
 980
 981         dest  = &np->daddr;
 982         src   = &np->rcv_saddr;
 983         destp = ntohs(inet->dport);
 984         srcp  = ntohs(inet->sport);
 985         seq_printf(seq,
 986                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
 987                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p\n",
 988                    bucket,
 989                    src->s6_addr32[0], src->s6_addr32[1],
 990                    src->s6_addr32[2], src->s6_addr32[3], srcp,
 991                    dest->s6_addr32[0], dest->s6_addr32[1],
 992                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
 993                    sp->sk_state,
 994                    atomic_read(&sp->sk_wmem_alloc),
 995                    atomic_read(&sp->sk_rmem_alloc),
 996                    0, 0L, 0,
 997                    sock_i_uid(sp), 0,
 998                    sock_i_ino(sp),
 999                    atomic_read(&sp->sk_refcnt), sp);
1000 }
1001
1002 static int udp6_seq_show(struct seq_file *seq, void *v)
1003 {
1004         if (v == SEQ_START_TOKEN)
1005                 seq_printf(seq,
1006                            "  sl  "
1007                            "local_address                         "
1008                            "remote_address                        "
1009                            "st tx_queue rx_queue tr tm->when retrnsmt"
1010                            "   uid  timeout inode\n");
1011         else
1012                 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1013         return 0;
1014 }
1015
1016 static struct file_operations udp6_seq_fops;
1017 static struct udp_seq_afinfo udp6_seq_afinfo = {
1018         .owner          = THIS_MODULE,
1019         .name           = "udp6",
1020         .family         = AF_INET6,
1021         .seq_show       = udp6_seq_show,
1022         .seq_fops       = &udp6_seq_fops,
1023 };
1024
1025 int __init udp6_proc_init(void)
1026 {
1027         return udp_proc_register(&udp6_seq_afinfo);
1028 }
1029
1030 void udp6_proc_exit(void) {
1031         udp_proc_unregister(&udp6_seq_afinfo);
1032 }
1033 #endif /* CONFIG_PROC_FS */
1034
1035 /* ------------------------------------------------------------------------ */
1036
1037 struct proto udpv6_prot = {
1038         .name =         "UDPv6",
1039         .owner =        THIS_MODULE,
1040         .close =        udpv6_close,
1041         .connect =      ip6_datagram_connect,
1042         .disconnect =   udp_disconnect,
1043         .ioctl =        udp_ioctl,
1044         .destroy =      udpv6_destroy_sock,
1045         .setsockopt =   udpv6_setsockopt,
1046         .getsockopt =   udpv6_getsockopt,
1047         .sendmsg =      udpv6_sendmsg,
1048         .recvmsg =      udpv6_recvmsg,
1049         .backlog_rcv =  udpv6_queue_rcv_skb,
1050         .hash =         udp_v6_hash,
1051         .unhash =       udp_v6_unhash,
1052         .get_port =     udp_v6_get_port,
1053         .obj_size =     sizeof(struct udp6_sock),
1054 };
1055
1056 static struct inet_protosw udpv6_protosw = {
1057         .type =      SOCK_DGRAM,
1058         .protocol =  IPPROTO_UDP,
1059         .prot =      &udpv6_prot,
1060         .ops =       &inet6_dgram_ops,
1061         .capability =-1,
1062         .no_check =  UDP_CSUM_DEFAULT,
1063         .flags =     INET_PROTOSW_PERMANENT,
1064 };
1065
1066
1067 void __init udpv6_init(void)
1068 {
1069         if (inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP) < 0)
1070                 printk(KERN_ERR "udpv6_init: Could not register protocol\n");
1071         inet6_register_protosw(&udpv6_protosw);
1072 }