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 <linux/skbuff.h>
  40 #include <asm/uaccess.h>
  41
  42 #include <net/sock.h>
  43 #include <net/snmp.h>
  44
  45 #include <net/ipv6.h>
  46 #include <net/ndisc.h>
  47 #include <net/protocol.h>
  48 #include <net/transp_v6.h>
  49 #include <net/ip6_route.h>
  50 #include <net/addrconf.h>
  51 #include <net/ip.h>
  52 #include <net/udp.h>
  53 #include <net/raw.h>
  54 #include <net/inet_common.h>
  55 #include <net/tcp_states.h>
  56
  57 #include <net/ip6_checksum.h>
  58 #include <net/xfrm.h>
  59
  60 #include <linux/proc_fs.h>
  61 #include <linux/seq_file.h>
  62
  63 DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6) __read_mostly;
  64
  65 /* Grrr, addr_type already calculated by caller, but I don't want
  66  * to add some silly "cookie" argument to this method just for that.
  67  */
  68 static int udp_v6_get_port(struct sock *sk, unsigned short snum)
  69 {
  70         struct sock *sk2;
  71         struct hlist_node *node;
  72
  73         write_lock_bh(&udp_hash_lock);
  74         if (snum == 0) {
  75                 int best_size_so_far, best, result, i;
  76
  77                 if (udp_port_rover > sysctl_local_port_range[1] ||
  78                     udp_port_rover < sysctl_local_port_range[0])
  79                         udp_port_rover = sysctl_local_port_range[0];
  80                 best_size_so_far = 32767;
  81                 best = result = udp_port_rover;
  82                 for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) {
  83                         int size;
  84                         struct hlist_head *list;
  85
  86                         list = &udp_hash[result & (UDP_HTABLE_SIZE - 1)];
  87                         if (hlist_empty(list)) {
  88                                 if (result > sysctl_local_port_range[1])
  89                                         result = sysctl_local_port_range[0] +
  90                                                 ((result - sysctl_local_port_range[0]) &
  91                                                  (UDP_HTABLE_SIZE - 1));
  92                                 goto gotit;
  93                         }
  94                         size = 0;
  95                         sk_for_each(sk2, node, list)
  96                                 if (++size >= best_size_so_far)
  97                                         goto next;
  98                         best_size_so_far = size;
  99                         best = result;
 100                 next:;
 101                 }
 102                 result = best;
 103                 for(i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++, result += UDP_HTABLE_SIZE) {
 104                         if (result > sysctl_local_port_range[1])
 105                                 result = sysctl_local_port_range[0]
 106                                         + ((result - sysctl_local_port_range[0]) &
 107                                            (UDP_HTABLE_SIZE - 1));
 108                         if (!udp_lport_inuse(result))
 109                                 break;
 110                 }
 111                 if (i >= (1 << 16) / UDP_HTABLE_SIZE)
 112                         goto fail;
 113 gotit:
 114                 udp_port_rover = snum = result;
 115         } else {
 116                 sk_for_each(sk2, node,
 117                             &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]) {
 118                         if (inet_sk(sk2)->num == snum &&
 119                             sk2 != sk &&
 120                             (!sk2->sk_bound_dev_if ||
 121                              !sk->sk_bound_dev_if ||
 122                              sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 123                             (!sk2->sk_reuse || !sk->sk_reuse) &&
 124                             ipv6_rcv_saddr_equal(sk, sk2))
 125                                 goto fail;
 126                 }
 127         }
 128
 129         inet_sk(sk)->num = snum;
 130         if (sk_unhashed(sk)) {
 131                 sk_add_node(sk, &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]);
 132                 sock_prot_inc_use(sk->sk_prot);
 133         }
 134         write_unlock_bh(&udp_hash_lock);
 135         return 0;
 136
 137 fail:
 138         write_unlock_bh(&udp_hash_lock);
 139         return 1;
 140 }
 141
 142 static void udp_v6_hash(struct sock *sk)
 143 {
 144         BUG();
 145 }
 146
 147 static void udp_v6_unhash(struct sock *sk)
 148 {
 149         write_lock_bh(&udp_hash_lock);
 150         if (sk_del_node_init(sk)) {
 151                 inet_sk(sk)->num = 0;
 152                 sock_prot_dec_use(sk->sk_prot);
 153         }
 154         write_unlock_bh(&udp_hash_lock);
 155 }
 156
 157 static struct sock *udp_v6_lookup(struct in6_addr *saddr, u16 sport,
 158                                   struct in6_addr *daddr, u16 dport, int dif)
 159 {
 160         struct sock *sk, *result = NULL;
 161         struct hlist_node *node;
 162         unsigned short hnum = ntohs(dport);
 163         int badness = -1;
 164
 165         read_lock(&udp_hash_lock);
 166         sk_for_each(sk, node, &udp_hash[hnum & (UDP_HTABLE_SIZE - 1)]) {
 167                 struct inet_sock *inet = inet_sk(sk);
 168
 169                 if (inet->num == hnum && sk->sk_family == PF_INET6) {
 170                         struct ipv6_pinfo *np = inet6_sk(sk);
 171                         int score = 0;
 172                         if (inet->dport) {
 173                                 if (inet->dport != sport)
 174                                         continue;
 175                                 score++;
 176                         }
 177                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 178                                 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
 179                                         continue;
 180                                 score++;
 181                         }
 182                         if (!ipv6_addr_any(&np->daddr)) {
 183                                 if (!ipv6_addr_equal(&np->daddr, saddr))
 184                                         continue;
 185                                 score++;
 186                         }
 187                         if (sk->sk_bound_dev_if) {
 188                                 if (sk->sk_bound_dev_if != dif)
 189                                         continue;
 190                                 score++;
 191                         }
 192                         if(score == 4) {
 193                                 result = sk;
 194                                 break;
 195                         } else if(score > badness) {
 196                                 result = sk;
 197                                 badness = score;
 198                         }
 199                 }
 200         }
 201         if (result)
 202                 sock_hold(result);
 203         read_unlock(&udp_hash_lock);
 204         return result;
 205 }
 206
 207 /*
 208  *
 209  */
 210
 211 static void udpv6_close(struct sock *sk, long timeout)
 212 {
 213         sk_common_release(sk);
 214 }
 215
 216 /*
 217  *      This should be easy, if there is something there we
 218  *      return it, otherwise we block.
 219  */
 220
 221 static int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 222                   struct msghdr *msg, size_t len,
 223                   int noblock, int flags, int *addr_len)
 224 {
 225         struct ipv6_pinfo *np = inet6_sk(sk);
 226         struct inet_sock *inet = inet_sk(sk);
 227         struct sk_buff *skb;
 228         size_t copied;
 229         int err;
 230
 231         if (addr_len)
 232                 *addr_len=sizeof(struct sockaddr_in6);
 233
 234         if (flags & MSG_ERRQUEUE)
 235                 return ipv6_recv_error(sk, msg, len);
 236
 237 try_again:
 238         skb = skb_recv_datagram(sk, flags, noblock, &err);
 239         if (!skb)
 240                 goto out;
 241
 242         copied = skb->len - sizeof(struct udphdr);
 243         if (copied > len) {
 244                 copied = len;
 245                 msg->msg_flags |= MSG_TRUNC;
 246         }
 247
 248         if (skb->ip_summed==CHECKSUM_UNNECESSARY) {
 249                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 250                                               copied);
 251         } else if (msg->msg_flags&MSG_TRUNC) {
 252                 if (__skb_checksum_complete(skb))
 253                         goto csum_copy_err;
 254                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 255                                               copied);
 256         } else {
 257                 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 258                 if (err == -EINVAL)
 259                         goto csum_copy_err;
 260         }
 261         if (err)
 262                 goto out_free;
 263
 264         sock_recv_timestamp(msg, sk, skb);
 265
 266         /* Copy the address. */
 267         if (msg->msg_name) {
 268                 struct sockaddr_in6 *sin6;
 269
 270                 sin6 = (struct sockaddr_in6 *) msg->msg_name;
 271                 sin6->sin6_family = AF_INET6;
 272                 sin6->sin6_port = skb->h.uh->source;
 273                 sin6->sin6_flowinfo = 0;
 274                 sin6->sin6_scope_id = 0;
 275
 276                 if (skb->protocol == htons(ETH_P_IP))
 277                         ipv6_addr_set(&sin6->sin6_addr, 0, 0,
 278                                       htonl(0xffff), skb->nh.iph->saddr);
 279                 else {
 280                         ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
 281                         if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 282                                 sin6->sin6_scope_id = IP6CB(skb)->iif;
 283                 }
 284
 285         }
 286         if (skb->protocol == htons(ETH_P_IP)) {
 287                 if (inet->cmsg_flags)
 288                         ip_cmsg_recv(msg, skb);
 289         } else {
 290                 if (np->rxopt.all)
 291                         datagram_recv_ctl(sk, msg, skb);
 292         }
 293
 294         err = copied;
 295         if (flags & MSG_TRUNC)
 296                 err = skb->len - sizeof(struct udphdr);
 297
 298 out_free:
 299         skb_free_datagram(sk, skb);
 300 out:
 301         return err;
 302
 303 csum_copy_err:
 304         skb_kill_datagram(sk, skb, flags);
 305
 306         if (flags & MSG_DONTWAIT) {
 307                 UDP6_INC_STATS_USER(UDP_MIB_INERRORS);
 308                 return -EAGAIN;
 309         }
 310         goto try_again;
 311 }
 312
 313 static void udpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 314                int type, int code, int offset, __u32 info)
 315 {
 316         struct ipv6_pinfo *np;
 317         struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
 318         struct in6_addr *saddr = &hdr->saddr;
 319         struct in6_addr *daddr = &hdr->daddr;
 320         struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 321         struct sock *sk;
 322         int err;
 323
 324         sk = udp_v6_lookup(daddr, uh->dest, saddr, uh->source, inet6_iif(skb));
 325
 326         if (sk == NULL)
 327                 return;
 328
 329         np = inet6_sk(sk);
 330
 331         if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 332                 goto out;
 333
 334         if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 335                 goto out;
 336
 337         if (np->recverr)
 338                 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 339
 340         sk->sk_err = err;
 341         sk->sk_error_report(sk);
 342 out:
 343         sock_put(sk);
 344 }
 345
 346 static inline int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
 347 {
 348         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
 349                 kfree_skb(skb);
 350                 return -1;
 351         }
 352
 353         if (skb_checksum_complete(skb)) {
 354                 UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 355                 kfree_skb(skb);
 356                 return 0;
 357         }
 358
 359         if (sock_queue_rcv_skb(sk,skb)<0) {
 360                 UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 361                 kfree_skb(skb);
 362                 return 0;
 363         }
 364         UDP6_INC_STATS_BH(UDP_MIB_INDATAGRAMS);
 365         return 0;
 366 }
 367
 368 static struct sock *udp_v6_mcast_next(struct sock *sk,
 369                                       u16 loc_port, struct in6_addr *loc_addr,
 370                                       u16 rmt_port, struct in6_addr *rmt_addr,
 371                                       int dif)
 372 {
 373         struct hlist_node *node;
 374         struct sock *s = sk;
 375         unsigned short num = ntohs(loc_port);
 376
 377         sk_for_each_from(s, node) {
 378                 struct inet_sock *inet = inet_sk(s);
 379
 380                 if (inet->num == num && s->sk_family == PF_INET6) {
 381                         struct ipv6_pinfo *np = inet6_sk(s);
 382                         if (inet->dport) {
 383                                 if (inet->dport != rmt_port)
 384                                         continue;
 385                         }
 386                         if (!ipv6_addr_any(&np->daddr) &&
 387                             !ipv6_addr_equal(&np->daddr, rmt_addr))
 388                                 continue;
 389
 390                         if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 391                                 continue;
 392
 393                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 394                                 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
 395                                         continue;
 396                         }
 397                         if(!inet6_mc_check(s, loc_addr, rmt_addr))
 398                                 continue;
 399                         return s;
 400                 }
 401         }
 402         return NULL;
 403 }
 404
 405 /*
 406  * Note: called only from the BH handler context,
 407  * so we don't need to lock the hashes.
 408  */
 409 static void udpv6_mcast_deliver(struct udphdr *uh,
 410                                 struct in6_addr *saddr, struct in6_addr *daddr,
 411                                 struct sk_buff *skb)
 412 {
 413         struct sock *sk, *sk2;
 414         int dif;
 415
 416         read_lock(&udp_hash_lock);
 417         sk = sk_head(&udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]);
 418         dif = inet6_iif(skb);
 419         sk = udp_v6_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif);
 420         if (!sk) {
 421                 kfree_skb(skb);
 422                 goto out;
 423         }
 424
 425         sk2 = sk;
 426         while ((sk2 = udp_v6_mcast_next(sk_next(sk2), uh->dest, daddr,
 427                                         uh->source, saddr, dif))) {
 428                 struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC);
 429                 if (buff)
 430                         udpv6_queue_rcv_skb(sk2, buff);
 431         }
 432         udpv6_queue_rcv_skb(sk, skb);
 433 out:
 434         read_unlock(&udp_hash_lock);
 435 }
 436
 437 static int udpv6_rcv(struct sk_buff **pskb)
 438 {
 439         struct sk_buff *skb = *pskb;
 440         struct sock *sk;
 441         struct udphdr *uh;
 442         struct net_device *dev = skb->dev;
 443         struct in6_addr *saddr, *daddr;
 444         u32 ulen = 0;
 445
 446         if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 447                 goto short_packet;
 448
 449         saddr = &skb->nh.ipv6h->saddr;
 450         daddr = &skb->nh.ipv6h->daddr;
 451         uh = skb->h.uh;
 452
 453         ulen = ntohs(uh->len);
 454
 455         /* Check for jumbo payload */
 456         if (ulen == 0)
 457                 ulen = skb->len;
 458
 459         if (ulen > skb->len || ulen < sizeof(*uh))
 460                 goto short_packet;
 461
 462         if (uh->check == 0) {
 463                 /* RFC 2460 section 8.1 says that we SHOULD log
 464                    this error. Well, it is reasonable.
 465                  */
 466                 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
 467                 goto discard;
 468         }
 469
 470         if (ulen < skb->len) {
 471                 if (pskb_trim_rcsum(skb, ulen))
 472                         goto discard;
 473                 saddr = &skb->nh.ipv6h->saddr;
 474                 daddr = &skb->nh.ipv6h->daddr;
 475                 uh = skb->h.uh;
 476         }
 477
 478         if (skb->ip_summed == CHECKSUM_HW &&
 479             !csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, skb->csum))
 480                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 481
 482         if (skb->ip_summed != CHECKSUM_UNNECESSARY)
 483                 skb->csum = ~csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, 0);
 484
 485         /*
 486          *      Multicast receive code
 487          */
 488         if (ipv6_addr_is_multicast(daddr)) {
 489                 udpv6_mcast_deliver(uh, saddr, daddr, skb);
 490                 return 0;
 491         }
 492
 493         /* Unicast */
 494
 495         /*
 496          * check socket cache ... must talk to Alan about his plans
 497          * for sock caches... i'll skip this for now.
 498          */
 499         sk = udp_v6_lookup(saddr, uh->source, daddr, uh->dest, inet6_iif(skb));
 500
 501         if (sk == NULL) {
 502                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 503                         goto discard;
 504
 505                 if (skb_checksum_complete(skb))
 506                         goto discard;
 507                 UDP6_INC_STATS_BH(UDP_MIB_NOPORTS);
 508
 509                 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0, dev);
 510
 511                 kfree_skb(skb);
 512                 return(0);
 513         }
 514
 515         /* deliver */
 516
 517         udpv6_queue_rcv_skb(sk, skb);
 518         sock_put(sk);
 519         return(0);
 520
 521 short_packet:
 522         if (net_ratelimit())
 523                 printk(KERN_DEBUG "UDP: short packet: %d/%u\n", ulen, skb->len);
 524
 525 discard:
 526         UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 527         kfree_skb(skb);
 528         return(0);
 529 }
 530 /*
 531  * Throw away all pending data and cancel the corking. Socket is locked.
 532  */
 533 static void udp_v6_flush_pending_frames(struct sock *sk)
 534 {
 535         struct udp_sock *up = udp_sk(sk);
 536
 537         if (up->pending) {
 538                 up->len = 0;
 539                 up->pending = 0;
 540                 ip6_flush_pending_frames(sk);
 541         }
 542 }
 543
 544 /*
 545  *      Sending
 546  */
 547
 548 static int udp_v6_push_pending_frames(struct sock *sk, struct udp_sock *up)
 549 {
 550         struct sk_buff *skb;
 551         struct udphdr *uh;
 552         struct inet_sock *inet = inet_sk(sk);
 553         struct flowi *fl = &inet->cork.fl;
 554         int err = 0;
 555
 556         /* Grab the skbuff where UDP header space exists. */
 557         if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 558                 goto out;
 559
 560         /*
 561          * Create a UDP header
 562          */
 563         uh = skb->h.uh;
 564         uh->source = fl->fl_ip_sport;
 565         uh->dest = fl->fl_ip_dport;
 566         uh->len = htons(up->len);
 567         uh->check = 0;
 568
 569         if (sk->sk_no_check == UDP_CSUM_NOXMIT) {
 570                 skb->ip_summed = CHECKSUM_NONE;
 571                 goto send;
 572         }
 573
 574         if (skb_queue_len(&sk->sk_write_queue) == 1) {
 575                 skb->csum = csum_partial((char *)uh,
 576                                 sizeof(struct udphdr), skb->csum);
 577                 uh->check = csum_ipv6_magic(&fl->fl6_src,
 578                                             &fl->fl6_dst,
 579                                             up->len, fl->proto, skb->csum);
 580         } else {
 581                 u32 tmp_csum = 0;
 582
 583                 skb_queue_walk(&sk->sk_write_queue, skb) {
 584                         tmp_csum = csum_add(tmp_csum, skb->csum);
 585                 }
 586                 tmp_csum = csum_partial((char *)uh,
 587                                 sizeof(struct udphdr), tmp_csum);
 588                 tmp_csum = csum_ipv6_magic(&fl->fl6_src,
 589                                            &fl->fl6_dst,
 590                                            up->len, fl->proto, tmp_csum);
 591                 uh->check = tmp_csum;
 592
 593         }
 594         if (uh->check == 0)
 595                 uh->check = -1;
 596
 597 send:
 598         err = ip6_push_pending_frames(sk);
 599 out:
 600         up->len = 0;
 601         up->pending = 0;
 602         return err;
 603 }
 604
 605 static int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 606                   struct msghdr *msg, size_t len)
 607 {
 608         struct ipv6_txoptions opt_space;
 609         struct udp_sock *up = udp_sk(sk);
 610         struct inet_sock *inet = inet_sk(sk);
 611         struct ipv6_pinfo *np = inet6_sk(sk);
 612         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
 613         struct in6_addr *daddr, *final_p = NULL, final;
 614         struct ipv6_txoptions *opt = NULL;
 615         struct ip6_flowlabel *flowlabel = NULL;
 616         struct flowi *fl = &inet->cork.fl;
 617         struct dst_entry *dst;
 618         int addr_len = msg->msg_namelen;
 619         int ulen = len;
 620         int hlimit = -1;
 621         int tclass = -1;
 622         int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
 623         int err;
 624         int connected = 0;
 625
 626         /* destination address check */
 627         if (sin6) {
 628                 if (addr_len < offsetof(struct sockaddr, sa_data))
 629                         return -EINVAL;
 630
 631                 switch (sin6->sin6_family) {
 632                 case AF_INET6:
 633                         if (addr_len < SIN6_LEN_RFC2133)
 634                                 return -EINVAL;
 635                         daddr = &sin6->sin6_addr;
 636                         break;
 637                 case AF_INET:
 638                         goto do_udp_sendmsg;
 639                 case AF_UNSPEC:
 640                         msg->msg_name = sin6 = NULL;
 641                         msg->msg_namelen = addr_len = 0;
 642                         daddr = NULL;
 643                         break;
 644                 default:
 645                         return -EINVAL;
 646                 }
 647         } else if (!up->pending) {
 648                 if (sk->sk_state != TCP_ESTABLISHED)
 649                         return -EDESTADDRREQ;
 650                 daddr = &np->daddr;
 651         } else
 652                 daddr = NULL;
 653
 654         if (daddr) {
 655                 if (ipv6_addr_type(daddr) == IPV6_ADDR_MAPPED) {
 656                         struct sockaddr_in sin;
 657                         sin.sin_family = AF_INET;
 658                         sin.sin_port = sin6 ? sin6->sin6_port : inet->dport;
 659                         sin.sin_addr.s_addr = daddr->s6_addr32[3];
 660                         msg->msg_name = &sin;
 661                         msg->msg_namelen = sizeof(sin);
 662 do_udp_sendmsg:
 663                         if (__ipv6_only_sock(sk))
 664                                 return -ENETUNREACH;
 665                         return udp_sendmsg(iocb, sk, msg, len);
 666                 }
 667         }
 668
 669         if (up->pending == AF_INET)
 670                 return udp_sendmsg(iocb, sk, msg, len);
 671
 672         /* Rough check on arithmetic overflow,
 673            better check is made in ip6_build_xmit
 674            */
 675         if (len > INT_MAX - sizeof(struct udphdr))
 676                 return -EMSGSIZE;
 677
 678         if (up->pending) {
 679                 /*
 680                  * There are pending frames.
 681                  * The socket lock must be held while it's corked.
 682                  */
 683                 lock_sock(sk);
 684                 if (likely(up->pending)) {
 685                         if (unlikely(up->pending != AF_INET6)) {
 686                                 release_sock(sk);
 687                                 return -EAFNOSUPPORT;
 688                         }
 689                         dst = NULL;
 690                         goto do_append_data;
 691                 }
 692                 release_sock(sk);
 693         }
 694         ulen += sizeof(struct udphdr);
 695
 696         memset(fl, 0, sizeof(*fl));
 697
 698         if (sin6) {
 699                 if (sin6->sin6_port == 0)
 700                         return -EINVAL;
 701
 702                 fl->fl_ip_dport = sin6->sin6_port;
 703                 daddr = &sin6->sin6_addr;
 704
 705                 if (np->sndflow) {
 706                         fl->fl6_flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
 707                         if (fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
 708                                 flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 709                                 if (flowlabel == NULL)
 710                                         return -EINVAL;
 711                                 daddr = &flowlabel->dst;
 712                         }
 713                 }
 714
 715                 /*
 716                  * Otherwise it will be difficult to maintain
 717                  * sk->sk_dst_cache.
 718                  */
 719                 if (sk->sk_state == TCP_ESTABLISHED &&
 720                     ipv6_addr_equal(daddr, &np->daddr))
 721                         daddr = &np->daddr;
 722
 723                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 724                     sin6->sin6_scope_id &&
 725                     ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
 726                         fl->oif = sin6->sin6_scope_id;
 727         } else {
 728                 if (sk->sk_state != TCP_ESTABLISHED)
 729                         return -EDESTADDRREQ;
 730
 731                 fl->fl_ip_dport = inet->dport;
 732                 daddr = &np->daddr;
 733                 fl->fl6_flowlabel = np->flow_label;
 734                 connected = 1;
 735         }
 736
 737         if (!fl->oif)
 738                 fl->oif = sk->sk_bound_dev_if;
 739
 740         if (msg->msg_controllen) {
 741                 opt = &opt_space;
 742                 memset(opt, 0, sizeof(struct ipv6_txoptions));
 743                 opt->tot_len = sizeof(*opt);
 744
 745                 err = datagram_send_ctl(msg, fl, opt, &hlimit, &tclass);
 746                 if (err < 0) {
 747                         fl6_sock_release(flowlabel);
 748                         return err;
 749                 }
 750                 if ((fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
 751                         flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 752                         if (flowlabel == NULL)
 753                                 return -EINVAL;
 754                 }
 755                 if (!(opt->opt_nflen|opt->opt_flen))
 756                         opt = NULL;
 757                 connected = 0;
 758         }
 759         if (opt == NULL)
 760                 opt = np->opt;
 761         if (flowlabel)
 762                 opt = fl6_merge_options(&opt_space, flowlabel, opt);
 763         opt = ipv6_fixup_options(&opt_space, opt);
 764
 765         fl->proto = IPPROTO_UDP;
 766         ipv6_addr_copy(&fl->fl6_dst, daddr);
 767         if (ipv6_addr_any(&fl->fl6_src) && !ipv6_addr_any(&np->saddr))
 768                 ipv6_addr_copy(&fl->fl6_src, &np->saddr);
 769         fl->fl_ip_sport = inet->sport;
 770
 771         /* merge ip6_build_xmit from ip6_output */
 772         if (opt && opt->srcrt) {
 773                 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
 774                 ipv6_addr_copy(&final, &fl->fl6_dst);
 775                 ipv6_addr_copy(&fl->fl6_dst, rt0->addr);
 776                 final_p = &final;
 777                 connected = 0;
 778         }
 779
 780         if (!fl->oif && ipv6_addr_is_multicast(&fl->fl6_dst)) {
 781                 fl->oif = np->mcast_oif;
 782                 connected = 0;
 783         }
 784
 785         err = ip6_dst_lookup(sk, &dst, fl);
 786         if (err)
 787                 goto out;
 788         if (final_p)
 789                 ipv6_addr_copy(&fl->fl6_dst, final_p);
 790
 791         if ((err = xfrm_lookup(&dst, fl, sk, 0)) < 0)
 792                 goto out;
 793
 794         if (hlimit < 0) {
 795                 if (ipv6_addr_is_multicast(&fl->fl6_dst))
 796                         hlimit = np->mcast_hops;
 797                 else
 798                         hlimit = np->hop_limit;
 799                 if (hlimit < 0)
 800                         hlimit = dst_metric(dst, RTAX_HOPLIMIT);
 801                 if (hlimit < 0)
 802                         hlimit = ipv6_get_hoplimit(dst->dev);
 803         }
 804
 805         if (tclass < 0) {
 806                 tclass = np->tclass;
 807                 if (tclass < 0)
 808                         tclass = 0;
 809         }
 810
 811         if (msg->msg_flags&MSG_CONFIRM)
 812                 goto do_confirm;
 813 back_from_confirm:
 814
 815         lock_sock(sk);
 816         if (unlikely(up->pending)) {
 817                 /* The socket is already corked while preparing it. */
 818                 /* ... which is an evident application bug. --ANK */
 819                 release_sock(sk);
 820
 821                 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
 822                 err = -EINVAL;
 823                 goto out;
 824         }
 825
 826         up->pending = AF_INET6;
 827
 828 do_append_data:
 829         up->len += ulen;
 830         err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov, ulen,
 831                 sizeof(struct udphdr), hlimit, tclass, opt, fl,
 832                 (struct rt6_info*)dst,
 833                 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 834         if (err)
 835                 udp_v6_flush_pending_frames(sk);
 836         else if (!corkreq)
 837                 err = udp_v6_push_pending_frames(sk, up);
 838
 839         if (dst) {
 840                 if (connected) {
 841                         ip6_dst_store(sk, dst,
 842                                       ipv6_addr_equal(&fl->fl6_dst, &np->daddr) ?
 843                                       &np->daddr : NULL);
 844                 } else {
 845                         dst_release(dst);
 846                 }
 847         }
 848
 849         if (err > 0)
 850                 err = np->recverr ? net_xmit_errno(err) : 0;
 851         release_sock(sk);
 852 out:
 853         fl6_sock_release(flowlabel);
 854         if (!err) {
 855                 UDP6_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS);
 856                 return len;
 857         }
 858         return err;
 859
 860 do_confirm:
 861         dst_confirm(dst);
 862         if (!(msg->msg_flags&MSG_PROBE) || len)
 863                 goto back_from_confirm;
 864         err = 0;
 865         goto out;
 866 }
 867
 868 static int udpv6_destroy_sock(struct sock *sk)
 869 {
 870         lock_sock(sk);
 871         udp_v6_flush_pending_frames(sk);
 872         release_sock(sk);
 873
 874         inet6_destroy_sock(sk);
 875
 876         return 0;
 877 }
 878
 879 /*
 880  *      Socket option code for UDP
 881  */
 882 static int udpv6_setsockopt(struct sock *sk, int level, int optname,
 883                           char __user *optval, int optlen)
 884 {
 885         struct udp_sock *up = udp_sk(sk);
 886         int val;
 887         int err = 0;
 888
 889         if (level != SOL_UDP)
 890                 return ipv6_setsockopt(sk, level, optname, optval, optlen);
 891
 892         if(optlen<sizeof(int))
 893                 return -EINVAL;
 894
 895         if (get_user(val, (int __user *)optval))
 896                 return -EFAULT;
 897
 898         switch(optname) {
 899         case UDP_CORK:
 900                 if (val != 0) {
 901                         up->corkflag = 1;
 902                 } else {
 903                         up->corkflag = 0;
 904                         lock_sock(sk);
 905                         udp_v6_push_pending_frames(sk, up);
 906                         release_sock(sk);
 907                 }
 908                 break;
 909
 910         case UDP_ENCAP:
 911                 switch (val) {
 912                 case 0:
 913                         up->encap_type = val;
 914                         break;
 915                 default:
 916                         err = -ENOPROTOOPT;
 917                         break;
 918                 }
 919                 break;
 920
 921         default:
 922                 err = -ENOPROTOOPT;
 923                 break;
 924         };
 925
 926         return err;
 927 }
 928
 929 static int udpv6_getsockopt(struct sock *sk, int level, int optname,
 930                           char __user *optval, int __user *optlen)
 931 {
 932         struct udp_sock *up = udp_sk(sk);
 933         int val, len;
 934
 935         if (level != SOL_UDP)
 936                 return ipv6_getsockopt(sk, level, optname, optval, optlen);
 937
 938         if(get_user(len,optlen))
 939                 return -EFAULT;
 940
 941         len = min_t(unsigned int, len, sizeof(int));
 942
 943         if(len < 0)
 944                 return -EINVAL;
 945
 946         switch(optname) {
 947         case UDP_CORK:
 948                 val = up->corkflag;
 949                 break;
 950
 951         case UDP_ENCAP:
 952                 val = up->encap_type;
 953                 break;
 954
 955         default:
 956                 return -ENOPROTOOPT;
 957         };
 958
 959         if(put_user(len, optlen))
 960                 return -EFAULT;
 961         if(copy_to_user(optval, &val,len))
 962                 return -EFAULT;
 963         return 0;
 964 }
 965
 966 static struct inet6_protocol udpv6_protocol = {
 967         .handler        =       udpv6_rcv,
 968         .err_handler    =       udpv6_err,
 969         .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
 970 };
 971
 972 /* ------------------------------------------------------------------------ */
 973 #ifdef CONFIG_PROC_FS
 974
 975 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
 976 {
 977         struct inet_sock *inet = inet_sk(sp);
 978         struct ipv6_pinfo *np = inet6_sk(sp);
 979         struct in6_addr *dest, *src;
 980         __u16 destp, srcp;
 981
 982         dest  = &np->daddr;
 983         src   = &np->rcv_saddr;
 984         destp = ntohs(inet->dport);
 985         srcp  = ntohs(inet->sport);
 986         seq_printf(seq,
 987                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
 988                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p\n",
 989                    bucket,
 990                    src->s6_addr32[0], src->s6_addr32[1],
 991                    src->s6_addr32[2], src->s6_addr32[3], srcp,
 992                    dest->s6_addr32[0], dest->s6_addr32[1],
 993                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
 994                    sp->sk_state,
 995                    atomic_read(&sp->sk_wmem_alloc),
 996                    atomic_read(&sp->sk_rmem_alloc),
 997                    0, 0L, 0,
 998                    sock_i_uid(sp), 0,
 999                    sock_i_ino(sp),
1000                    atomic_read(&sp->sk_refcnt), sp);
1001 }
1002
1003 static int udp6_seq_show(struct seq_file *seq, void *v)
1004 {
1005         if (v == SEQ_START_TOKEN)
1006                 seq_printf(seq,
1007                            "  sl  "
1008                            "local_address                         "
1009                            "remote_address                        "
1010                            "st tx_queue rx_queue tr tm->when retrnsmt"
1011                            "   uid  timeout inode\n");
1012         else
1013                 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1014         return 0;
1015 }
1016
1017 static struct file_operations udp6_seq_fops;
1018 static struct udp_seq_afinfo udp6_seq_afinfo = {
1019         .owner          = THIS_MODULE,
1020         .name           = "udp6",
1021         .family         = AF_INET6,
1022         .seq_show       = udp6_seq_show,
1023         .seq_fops       = &udp6_seq_fops,
1024 };
1025
1026 int __init udp6_proc_init(void)
1027 {
1028         return udp_proc_register(&udp6_seq_afinfo);
1029 }
1030
1031 void udp6_proc_exit(void) {
1032         udp_proc_unregister(&udp6_seq_afinfo);
1033 }
1034 #endif /* CONFIG_PROC_FS */
1035
1036 /* ------------------------------------------------------------------------ */
1037
1038 struct proto udpv6_prot = {
1039         .name =         "UDPv6",
1040         .owner =        THIS_MODULE,
1041         .close =        udpv6_close,
1042         .connect =      ip6_datagram_connect,
1043         .disconnect =   udp_disconnect,
1044         .ioctl =        udp_ioctl,
1045         .destroy =      udpv6_destroy_sock,
1046         .setsockopt =   udpv6_setsockopt,
1047         .getsockopt =   udpv6_getsockopt,
1048         .sendmsg =      udpv6_sendmsg,
1049         .recvmsg =      udpv6_recvmsg,
1050         .backlog_rcv =  udpv6_queue_rcv_skb,
1051         .hash =         udp_v6_hash,
1052         .unhash =       udp_v6_unhash,
1053         .get_port =     udp_v6_get_port,
1054         .obj_size =     sizeof(struct udp6_sock),
1055 };
1056
1057 static struct inet_protosw udpv6_protosw = {
1058         .type =      SOCK_DGRAM,
1059         .protocol =  IPPROTO_UDP,
1060         .prot =      &udpv6_prot,
1061         .ops =       &inet6_dgram_ops,
1062         .capability =-1,
1063         .no_check =  UDP_CSUM_DEFAULT,
1064         .flags =     INET_PROTOSW_PERMANENT,
1065 };
1066
1067
1068 void __init udpv6_init(void)
1069 {
1070         if (inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP) < 0)
1071                 printk(KERN_ERR "udpv6_init: Could not register protocol\n");
1072         inet6_register_protosw(&udpv6_protosw);
1073 }