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/errno.h>
  27 #include <linux/types.h>
  28 #include <linux/socket.h>
  29 #include <linux/sockios.h>
  30 #include <linux/sched.h>
  31 #include <linux/net.h>
  32 #include <linux/in6.h>
  33 #include <linux/netdevice.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/ipv6.h>
  36 #include <linux/icmpv6.h>
  37 #include <linux/init.h>
  38 #include <linux/skbuff.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(i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++, 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                 if (i >= (1 << 16) / UDP_HTABLE_SIZE)
 111                         goto fail;
 112 gotit:
 113                 udp_port_rover = snum = result;
 114         } else {
 115                 sk_for_each(sk2, node,
 116                             &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]) {
 117                         if (inet_sk(sk2)->num == snum &&
 118                             sk2 != sk &&
 119                             (!sk2->sk_bound_dev_if ||
 120                              !sk->sk_bound_dev_if ||
 121                              sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 122                             (!sk2->sk_reuse || !sk->sk_reuse) &&
 123                             ipv6_rcv_saddr_equal(sk, sk2))
 124                                 goto fail;
 125                 }
 126         }
 127
 128         inet_sk(sk)->num = snum;
 129         if (sk_unhashed(sk)) {
 130                 sk_add_node(sk, &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]);
 131                 sock_prot_inc_use(sk->sk_prot);
 132         }
 133         write_unlock_bh(&udp_hash_lock);
 134         return 0;
 135
 136 fail:
 137         write_unlock_bh(&udp_hash_lock);
 138         return 1;
 139 }
 140
 141 static void udp_v6_hash(struct sock *sk)
 142 {
 143         BUG();
 144 }
 145
 146 static void udp_v6_unhash(struct sock *sk)
 147 {
 148         write_lock_bh(&udp_hash_lock);
 149         if (sk_del_node_init(sk)) {
 150                 inet_sk(sk)->num = 0;
 151                 sock_prot_dec_use(sk->sk_prot);
 152         }
 153         write_unlock_bh(&udp_hash_lock);
 154 }
 155
 156 static struct sock *udp_v6_lookup(struct in6_addr *saddr, u16 sport,
 157                                   struct in6_addr *daddr, u16 dport, int dif)
 158 {
 159         struct sock *sk, *result = NULL;
 160         struct hlist_node *node;
 161         unsigned short hnum = ntohs(dport);
 162         int badness = -1;
 163
 164         read_lock(&udp_hash_lock);
 165         sk_for_each(sk, node, &udp_hash[hnum & (UDP_HTABLE_SIZE - 1)]) {
 166                 struct inet_sock *inet = inet_sk(sk);
 167
 168                 if (inet->num == hnum && sk->sk_family == PF_INET6) {
 169                         struct ipv6_pinfo *np = inet6_sk(sk);
 170                         int score = 0;
 171                         if (inet->dport) {
 172                                 if (inet->dport != sport)
 173                                         continue;
 174                                 score++;
 175                         }
 176                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 177                                 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
 178                                         continue;
 179                                 score++;
 180                         }
 181                         if (!ipv6_addr_any(&np->daddr)) {
 182                                 if (!ipv6_addr_equal(&np->daddr, saddr))
 183                                         continue;
 184                                 score++;
 185                         }
 186                         if (sk->sk_bound_dev_if) {
 187                                 if (sk->sk_bound_dev_if != dif)
 188                                         continue;
 189                                 score++;
 190                         }
 191                         if(score == 4) {
 192                                 result = sk;
 193                                 break;
 194                         } else if(score > badness) {
 195                                 result = sk;
 196                                 badness = score;
 197                         }
 198                 }
 199         }
 200         if (result)
 201                 sock_hold(result);
 202         read_unlock(&udp_hash_lock);
 203         return result;
 204 }
 205
 206 /*
 207  *
 208  */
 209
 210 static void udpv6_close(struct sock *sk, long timeout)
 211 {
 212         sk_common_release(sk);
 213 }
 214
 215 /*
 216  *      This should be easy, if there is something there we
 217  *      return it, otherwise we block.
 218  */
 219
 220 static int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 221                   struct msghdr *msg, size_t len,
 222                   int noblock, int flags, int *addr_len)
 223 {
 224         struct ipv6_pinfo *np = inet6_sk(sk);
 225         struct inet_sock *inet = inet_sk(sk);
 226         struct sk_buff *skb;
 227         size_t copied;
 228         int err;
 229
 230         if (addr_len)
 231                 *addr_len=sizeof(struct sockaddr_in6);
 232
 233         if (flags & MSG_ERRQUEUE)
 234                 return ipv6_recv_error(sk, msg, len);
 235
 236 try_again:
 237         skb = skb_recv_datagram(sk, flags, noblock, &err);
 238         if (!skb)
 239                 goto out;
 240
 241         copied = skb->len - sizeof(struct udphdr);
 242         if (copied > len) {
 243                 copied = len;
 244                 msg->msg_flags |= MSG_TRUNC;
 245         }
 246
 247         if (skb->ip_summed==CHECKSUM_UNNECESSARY) {
 248                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 249                                               copied);
 250         } else if (msg->msg_flags&MSG_TRUNC) {
 251                 if (__skb_checksum_complete(skb))
 252                         goto csum_copy_err;
 253                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 254                                               copied);
 255         } else {
 256                 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 257                 if (err == -EINVAL)
 258                         goto csum_copy_err;
 259         }
 260         if (err)
 261                 goto out_free;
 262
 263         sock_recv_timestamp(msg, sk, skb);
 264
 265         /* Copy the address. */
 266         if (msg->msg_name) {
 267                 struct sockaddr_in6 *sin6;
 268
 269                 sin6 = (struct sockaddr_in6 *) msg->msg_name;
 270                 sin6->sin6_family = AF_INET6;
 271                 sin6->sin6_port = skb->h.uh->source;
 272                 sin6->sin6_flowinfo = 0;
 273                 sin6->sin6_scope_id = 0;
 274
 275                 if (skb->protocol == htons(ETH_P_IP))
 276                         ipv6_addr_set(&sin6->sin6_addr, 0, 0,
 277                                       htonl(0xffff), skb->nh.iph->saddr);
 278                 else {
 279                         ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
 280                         if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 281                                 sin6->sin6_scope_id = IP6CB(skb)->iif;
 282                 }
 283
 284         }
 285         if (skb->protocol == htons(ETH_P_IP)) {
 286                 if (inet->cmsg_flags)
 287                         ip_cmsg_recv(msg, skb);
 288         } else {
 289                 if (np->rxopt.all)
 290                         datagram_recv_ctl(sk, msg, skb);
 291         }
 292
 293         err = copied;
 294         if (flags & MSG_TRUNC)
 295                 err = skb->len - sizeof(struct udphdr);
 296
 297 out_free:
 298         skb_free_datagram(sk, skb);
 299 out:
 300         return err;
 301
 302 csum_copy_err:
 303         skb_kill_datagram(sk, skb, flags);
 304
 305         if (flags & MSG_DONTWAIT) {
 306                 UDP6_INC_STATS_USER(UDP_MIB_INERRORS);
 307                 return -EAGAIN;
 308         }
 309         goto try_again;
 310 }
 311
 312 static void udpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 313                int type, int code, int offset, __u32 info)
 314 {
 315         struct ipv6_pinfo *np;
 316         struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
 317         struct net_device *dev = skb->dev;
 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, dev->ifindex);
 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         int rc;
 349
 350         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
 351                 kfree_skb(skb);
 352                 return -1;
 353         }
 354
 355         if (skb_checksum_complete(skb)) {
 356                 UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 357                 kfree_skb(skb);
 358                 return 0;
 359         }
 360
 361         if ((rc = sock_queue_rcv_skb(sk,skb)) < 0) {
 362                 /* Note that an ENOMEM error is charged twice */
 363                 if (rc == -ENOMEM)
 364                         UDP_INC_STATS_BH(UDP_MIB_RCVBUFERRORS);
 365                 UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 366                 kfree_skb(skb);
 367                 return 0;
 368         }
 369         UDP6_INC_STATS_BH(UDP_MIB_INDATAGRAMS);
 370         return 0;
 371 }
 372
 373 static struct sock *udp_v6_mcast_next(struct sock *sk,
 374                                       u16 loc_port, struct in6_addr *loc_addr,
 375                                       u16 rmt_port, struct in6_addr *rmt_addr,
 376                                       int dif)
 377 {
 378         struct hlist_node *node;
 379         struct sock *s = sk;
 380         unsigned short num = ntohs(loc_port);
 381
 382         sk_for_each_from(s, node) {
 383                 struct inet_sock *inet = inet_sk(s);
 384
 385                 if (inet->num == num && s->sk_family == PF_INET6) {
 386                         struct ipv6_pinfo *np = inet6_sk(s);
 387                         if (inet->dport) {
 388                                 if (inet->dport != rmt_port)
 389                                         continue;
 390                         }
 391                         if (!ipv6_addr_any(&np->daddr) &&
 392                             !ipv6_addr_equal(&np->daddr, rmt_addr))
 393                                 continue;
 394
 395                         if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 396                                 continue;
 397
 398                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 399                                 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
 400                                         continue;
 401                         }
 402                         if(!inet6_mc_check(s, loc_addr, rmt_addr))
 403                                 continue;
 404                         return s;
 405                 }
 406         }
 407         return NULL;
 408 }
 409
 410 /*
 411  * Note: called only from the BH handler context,
 412  * so we don't need to lock the hashes.
 413  */
 414 static void udpv6_mcast_deliver(struct udphdr *uh,
 415                                 struct in6_addr *saddr, struct in6_addr *daddr,
 416                                 struct sk_buff *skb)
 417 {
 418         struct sock *sk, *sk2;
 419         int dif;
 420
 421         read_lock(&udp_hash_lock);
 422         sk = sk_head(&udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]);
 423         dif = skb->dev->ifindex;
 424         sk = udp_v6_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif);
 425         if (!sk) {
 426                 kfree_skb(skb);
 427                 goto out;
 428         }
 429
 430         sk2 = sk;
 431         while ((sk2 = udp_v6_mcast_next(sk_next(sk2), uh->dest, daddr,
 432                                         uh->source, saddr, dif))) {
 433                 struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC);
 434                 if (buff)
 435                         udpv6_queue_rcv_skb(sk2, buff);
 436         }
 437         udpv6_queue_rcv_skb(sk, skb);
 438 out:
 439         read_unlock(&udp_hash_lock);
 440 }
 441
 442 static int udpv6_rcv(struct sk_buff **pskb)
 443 {
 444         struct sk_buff *skb = *pskb;
 445         struct sock *sk;
 446         struct udphdr *uh;
 447         struct net_device *dev = skb->dev;
 448         struct in6_addr *saddr, *daddr;
 449         u32 ulen = 0;
 450
 451         if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 452                 goto short_packet;
 453
 454         saddr = &skb->nh.ipv6h->saddr;
 455         daddr = &skb->nh.ipv6h->daddr;
 456         uh = skb->h.uh;
 457
 458         ulen = ntohs(uh->len);
 459
 460         /* Check for jumbo payload */
 461         if (ulen == 0)
 462                 ulen = skb->len;
 463
 464         if (ulen > skb->len || ulen < sizeof(*uh))
 465                 goto short_packet;
 466
 467         if (uh->check == 0) {
 468                 /* RFC 2460 section 8.1 says that we SHOULD log
 469                    this error. Well, it is reasonable.
 470                  */
 471                 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
 472                 goto discard;
 473         }
 474
 475         if (ulen < skb->len) {
 476                 if (pskb_trim_rcsum(skb, ulen))
 477                         goto discard;
 478                 saddr = &skb->nh.ipv6h->saddr;
 479                 daddr = &skb->nh.ipv6h->daddr;
 480                 uh = skb->h.uh;
 481         }
 482
 483         if (skb->ip_summed == CHECKSUM_COMPLETE &&
 484             !csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, skb->csum))
 485                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 486
 487         if (skb->ip_summed != CHECKSUM_UNNECESSARY)
 488                 skb->csum = ~csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, 0);
 489
 490         /*
 491          *      Multicast receive code
 492          */
 493         if (ipv6_addr_is_multicast(daddr)) {
 494                 udpv6_mcast_deliver(uh, saddr, daddr, skb);
 495                 return 0;
 496         }
 497
 498         /* Unicast */
 499
 500         /*
 501          * check socket cache ... must talk to Alan about his plans
 502          * for sock caches... i'll skip this for now.
 503          */
 504         sk = udp_v6_lookup(saddr, uh->source, daddr, uh->dest, dev->ifindex);
 505
 506         if (sk == NULL) {
 507                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 508                         goto discard;
 509
 510                 if (skb_checksum_complete(skb))
 511                         goto discard;
 512                 UDP6_INC_STATS_BH(UDP_MIB_NOPORTS);
 513
 514                 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0, dev);
 515
 516                 kfree_skb(skb);
 517                 return(0);
 518         }
 519
 520         /* deliver */
 521
 522         udpv6_queue_rcv_skb(sk, skb);
 523         sock_put(sk);
 524         return(0);
 525
 526 short_packet:
 527         if (net_ratelimit())
 528                 printk(KERN_DEBUG "UDP: short packet: %d/%u\n", ulen, skb->len);
 529
 530 discard:
 531         UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
 532         kfree_skb(skb);
 533         return(0);
 534 }
 535 /*
 536  * Throw away all pending data and cancel the corking. Socket is locked.
 537  */
 538 static void udp_v6_flush_pending_frames(struct sock *sk)
 539 {
 540         struct udp_sock *up = udp_sk(sk);
 541
 542         if (up->pending) {
 543                 up->len = 0;
 544                 up->pending = 0;
 545                 ip6_flush_pending_frames(sk);
 546         }
 547 }
 548
 549 /*
 550  *      Sending
 551  */
 552
 553 static int udp_v6_push_pending_frames(struct sock *sk, struct udp_sock *up)
 554 {
 555         struct sk_buff *skb;
 556         struct udphdr *uh;
 557         struct inet_sock *inet = inet_sk(sk);
 558         struct flowi *fl = &inet->cork.fl;
 559         int err = 0;
 560
 561         /* Grab the skbuff where UDP header space exists. */
 562         if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 563                 goto out;
 564
 565         /*
 566          * Create a UDP header
 567          */
 568         uh = skb->h.uh;
 569         uh->source = fl->fl_ip_sport;
 570         uh->dest = fl->fl_ip_dport;
 571         uh->len = htons(up->len);
 572         uh->check = 0;
 573
 574         if (sk->sk_no_check == UDP_CSUM_NOXMIT) {
 575                 skb->ip_summed = CHECKSUM_NONE;
 576                 goto send;
 577         }
 578
 579         if (skb_queue_len(&sk->sk_write_queue) == 1) {
 580                 skb->csum = csum_partial((char *)uh,
 581                                 sizeof(struct udphdr), skb->csum);
 582                 uh->check = csum_ipv6_magic(&fl->fl6_src,
 583                                             &fl->fl6_dst,
 584                                             up->len, fl->proto, skb->csum);
 585         } else {
 586                 u32 tmp_csum = 0;
 587
 588                 skb_queue_walk(&sk->sk_write_queue, skb) {
 589                         tmp_csum = csum_add(tmp_csum, skb->csum);
 590                 }
 591                 tmp_csum = csum_partial((char *)uh,
 592                                 sizeof(struct udphdr), tmp_csum);
 593                 tmp_csum = csum_ipv6_magic(&fl->fl6_src,
 594                                            &fl->fl6_dst,
 595                                            up->len, fl->proto, tmp_csum);
 596                 uh->check = tmp_csum;
 597
 598         }
 599         if (uh->check == 0)
 600                 uh->check = -1;
 601
 602 send:
 603         err = ip6_push_pending_frames(sk);
 604 out:
 605         up->len = 0;
 606         up->pending = 0;
 607         return err;
 608 }
 609
 610 static int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 611                   struct msghdr *msg, size_t len)
 612 {
 613         struct ipv6_txoptions opt_space;
 614         struct udp_sock *up = udp_sk(sk);
 615         struct inet_sock *inet = inet_sk(sk);
 616         struct ipv6_pinfo *np = inet6_sk(sk);
 617         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
 618         struct in6_addr *daddr, *final_p = NULL, final;
 619         struct ipv6_txoptions *opt = NULL;
 620         struct ip6_flowlabel *flowlabel = NULL;
 621         struct flowi *fl = &inet->cork.fl;
 622         struct dst_entry *dst;
 623         int addr_len = msg->msg_namelen;
 624         int ulen = len;
 625         int hlimit = -1;
 626         int tclass = -1;
 627         int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
 628         int err;
 629         int connected = 0;
 630
 631         /* destination address check */
 632         if (sin6) {
 633                 if (addr_len < offsetof(struct sockaddr, sa_data))
 634                         return -EINVAL;
 635
 636                 switch (sin6->sin6_family) {
 637                 case AF_INET6:
 638                         if (addr_len < SIN6_LEN_RFC2133)
 639                                 return -EINVAL;
 640                         daddr = &sin6->sin6_addr;
 641                         break;
 642                 case AF_INET:
 643                         goto do_udp_sendmsg;
 644                 case AF_UNSPEC:
 645                         msg->msg_name = sin6 = NULL;
 646                         msg->msg_namelen = addr_len = 0;
 647                         daddr = NULL;
 648                         break;
 649                 default:
 650                         return -EINVAL;
 651                 }
 652         } else if (!up->pending) {
 653                 if (sk->sk_state != TCP_ESTABLISHED)
 654                         return -EDESTADDRREQ;
 655                 daddr = &np->daddr;
 656         } else
 657                 daddr = NULL;
 658
 659         if (daddr) {
 660                 if (ipv6_addr_type(daddr) == IPV6_ADDR_MAPPED) {
 661                         struct sockaddr_in sin;
 662                         sin.sin_family = AF_INET;
 663                         sin.sin_port = sin6 ? sin6->sin6_port : inet->dport;
 664                         sin.sin_addr.s_addr = daddr->s6_addr32[3];
 665                         msg->msg_name = &sin;
 666                         msg->msg_namelen = sizeof(sin);
 667 do_udp_sendmsg:
 668                         if (__ipv6_only_sock(sk))
 669                                 return -ENETUNREACH;
 670                         return udp_sendmsg(iocb, sk, msg, len);
 671                 }
 672         }
 673
 674         if (up->pending == AF_INET)
 675                 return udp_sendmsg(iocb, sk, msg, len);
 676
 677         /* Rough check on arithmetic overflow,
 678            better check is made in ip6_build_xmit
 679            */
 680         if (len > INT_MAX - sizeof(struct udphdr))
 681                 return -EMSGSIZE;
 682
 683         if (up->pending) {
 684                 /*
 685                  * There are pending frames.
 686                  * The socket lock must be held while it's corked.
 687                  */
 688                 lock_sock(sk);
 689                 if (likely(up->pending)) {
 690                         if (unlikely(up->pending != AF_INET6)) {
 691                                 release_sock(sk);
 692                                 return -EAFNOSUPPORT;
 693                         }
 694                         dst = NULL;
 695                         goto do_append_data;
 696                 }
 697                 release_sock(sk);
 698         }
 699         ulen += sizeof(struct udphdr);
 700
 701         memset(fl, 0, sizeof(*fl));
 702
 703         if (sin6) {
 704                 if (sin6->sin6_port == 0)
 705                         return -EINVAL;
 706
 707                 fl->fl_ip_dport = sin6->sin6_port;
 708                 daddr = &sin6->sin6_addr;
 709
 710                 if (np->sndflow) {
 711                         fl->fl6_flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
 712                         if (fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
 713                                 flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 714                                 if (flowlabel == NULL)
 715                                         return -EINVAL;
 716                                 daddr = &flowlabel->dst;
 717                         }
 718                 }
 719
 720                 /*
 721                  * Otherwise it will be difficult to maintain
 722                  * sk->sk_dst_cache.
 723                  */
 724                 if (sk->sk_state == TCP_ESTABLISHED &&
 725                     ipv6_addr_equal(daddr, &np->daddr))
 726                         daddr = &np->daddr;
 727
 728                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 729                     sin6->sin6_scope_id &&
 730                     ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
 731                         fl->oif = sin6->sin6_scope_id;
 732         } else {
 733                 if (sk->sk_state != TCP_ESTABLISHED)
 734                         return -EDESTADDRREQ;
 735
 736                 fl->fl_ip_dport = inet->dport;
 737                 daddr = &np->daddr;
 738                 fl->fl6_flowlabel = np->flow_label;
 739                 connected = 1;
 740         }
 741
 742         if (!fl->oif)
 743                 fl->oif = sk->sk_bound_dev_if;
 744
 745         if (msg->msg_controllen) {
 746                 opt = &opt_space;
 747                 memset(opt, 0, sizeof(struct ipv6_txoptions));
 748                 opt->tot_len = sizeof(*opt);
 749
 750                 err = datagram_send_ctl(msg, fl, opt, &hlimit, &tclass);
 751                 if (err < 0) {
 752                         fl6_sock_release(flowlabel);
 753                         return err;
 754                 }
 755                 if ((fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
 756                         flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 757                         if (flowlabel == NULL)
 758                                 return -EINVAL;
 759                 }
 760                 if (!(opt->opt_nflen|opt->opt_flen))
 761                         opt = NULL;
 762                 connected = 0;
 763         }
 764         if (opt == NULL)
 765                 opt = np->opt;
 766         if (flowlabel)
 767                 opt = fl6_merge_options(&opt_space, flowlabel, opt);
 768         opt = ipv6_fixup_options(&opt_space, opt);
 769
 770         fl->proto = IPPROTO_UDP;
 771         ipv6_addr_copy(&fl->fl6_dst, daddr);
 772         if (ipv6_addr_any(&fl->fl6_src) && !ipv6_addr_any(&np->saddr))
 773                 ipv6_addr_copy(&fl->fl6_src, &np->saddr);
 774         fl->fl_ip_sport = inet->sport;
 775
 776         /* merge ip6_build_xmit from ip6_output */
 777         if (opt && opt->srcrt) {
 778                 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
 779                 ipv6_addr_copy(&final, &fl->fl6_dst);
 780                 ipv6_addr_copy(&fl->fl6_dst, rt0->addr);
 781                 final_p = &final;
 782                 connected = 0;
 783         }
 784
 785         if (!fl->oif && ipv6_addr_is_multicast(&fl->fl6_dst)) {
 786                 fl->oif = np->mcast_oif;
 787                 connected = 0;
 788         }
 789
 790         security_sk_classify_flow(sk, fl);
 791
 792         err = ip6_sk_dst_lookup(sk, &dst, fl);
 793         if (err)
 794                 goto out;
 795         if (final_p)
 796                 ipv6_addr_copy(&fl->fl6_dst, final_p);
 797
 798         if ((err = xfrm_lookup(&dst, fl, sk, 0)) < 0)
 799                 goto out;
 800
 801         if (hlimit < 0) {
 802                 if (ipv6_addr_is_multicast(&fl->fl6_dst))
 803                         hlimit = np->mcast_hops;
 804                 else
 805                         hlimit = np->hop_limit;
 806                 if (hlimit < 0)
 807                         hlimit = dst_metric(dst, RTAX_HOPLIMIT);
 808                 if (hlimit < 0)
 809                         hlimit = ipv6_get_hoplimit(dst->dev);
 810         }
 811
 812         if (tclass < 0) {
 813                 tclass = np->tclass;
 814                 if (tclass < 0)
 815                         tclass = 0;
 816         }
 817
 818         if (msg->msg_flags&MSG_CONFIRM)
 819                 goto do_confirm;
 820 back_from_confirm:
 821
 822         lock_sock(sk);
 823         if (unlikely(up->pending)) {
 824                 /* The socket is already corked while preparing it. */
 825                 /* ... which is an evident application bug. --ANK */
 826                 release_sock(sk);
 827
 828                 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
 829                 err = -EINVAL;
 830                 goto out;
 831         }
 832
 833         up->pending = AF_INET6;
 834
 835 do_append_data:
 836         up->len += ulen;
 837         err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov, ulen,
 838                 sizeof(struct udphdr), hlimit, tclass, opt, fl,
 839                 (struct rt6_info*)dst,
 840                 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 841         if (err)
 842                 udp_v6_flush_pending_frames(sk);
 843         else if (!corkreq)
 844                 err = udp_v6_push_pending_frames(sk, up);
 845
 846         if (dst) {
 847                 if (connected) {
 848                         ip6_dst_store(sk, dst,
 849                                       ipv6_addr_equal(&fl->fl6_dst, &np->daddr) ?
 850                                       &np->daddr : NULL);
 851                 } else {
 852                         dst_release(dst);
 853                 }
 854         }
 855
 856         if (err > 0)
 857                 err = np->recverr ? net_xmit_errno(err) : 0;
 858         release_sock(sk);
 859 out:
 860         fl6_sock_release(flowlabel);
 861         if (!err) {
 862                 UDP6_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS);
 863                 return len;
 864         }
 865         /*
 866          * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
 867          * ENOBUFS might not be good (it's not tunable per se), but otherwise
 868          * we don't have a good statistic (IpOutDiscards but it can be too many
 869          * things).  We could add another new stat but at least for now that
 870          * seems like overkill.
 871          */
 872         if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
 873                 UDP_INC_STATS_USER(UDP_MIB_SNDBUFERRORS);
 874         }
 875         return err;
 876
 877 do_confirm:
 878         dst_confirm(dst);
 879         if (!(msg->msg_flags&MSG_PROBE) || len)
 880                 goto back_from_confirm;
 881         err = 0;
 882         goto out;
 883 }
 884
 885 static int udpv6_destroy_sock(struct sock *sk)
 886 {
 887         lock_sock(sk);
 888         udp_v6_flush_pending_frames(sk);
 889         release_sock(sk);
 890
 891         inet6_destroy_sock(sk);
 892
 893         return 0;
 894 }
 895
 896 /*
 897  *      Socket option code for UDP
 898  */
 899 static int do_udpv6_setsockopt(struct sock *sk, int level, int optname,
 900                           char __user *optval, int optlen)
 901 {
 902         struct udp_sock *up = udp_sk(sk);
 903         int val;
 904         int err = 0;
 905
 906         if(optlen<sizeof(int))
 907                 return -EINVAL;
 908
 909         if (get_user(val, (int __user *)optval))
 910                 return -EFAULT;
 911
 912         switch(optname) {
 913         case UDP_CORK:
 914                 if (val != 0) {
 915                         up->corkflag = 1;
 916                 } else {
 917                         up->corkflag = 0;
 918                         lock_sock(sk);
 919                         udp_v6_push_pending_frames(sk, up);
 920                         release_sock(sk);
 921                 }
 922                 break;
 923
 924         case UDP_ENCAP:
 925                 switch (val) {
 926                 case 0:
 927                         up->encap_type = val;
 928                         break;
 929                 default:
 930                         err = -ENOPROTOOPT;
 931                         break;
 932                 }
 933                 break;
 934
 935         default:
 936                 err = -ENOPROTOOPT;
 937                 break;
 938         };
 939
 940         return err;
 941 }
 942
 943 static int udpv6_setsockopt(struct sock *sk, int level, int optname,
 944                           char __user *optval, int optlen)
 945 {
 946         if (level != SOL_UDP)
 947                 return ipv6_setsockopt(sk, level, optname, optval, optlen);
 948         return do_udpv6_setsockopt(sk, level, optname, optval, optlen);
 949 }
 950
 951 #ifdef CONFIG_COMPAT
 952 static int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
 953                                    char __user *optval, int optlen)
 954 {
 955         if (level != SOL_UDP)
 956                 return compat_ipv6_setsockopt(sk, level, optname,
 957                                               optval, optlen);
 958         return do_udpv6_setsockopt(sk, level, optname, optval, optlen);
 959 }
 960 #endif
 961
 962 static int do_udpv6_getsockopt(struct sock *sk, int level, int optname,
 963                           char __user *optval, int __user *optlen)
 964 {
 965         struct udp_sock *up = udp_sk(sk);
 966         int val, len;
 967
 968         if(get_user(len,optlen))
 969                 return -EFAULT;
 970
 971         len = min_t(unsigned int, len, sizeof(int));
 972
 973         if(len < 0)
 974                 return -EINVAL;
 975
 976         switch(optname) {
 977         case UDP_CORK:
 978                 val = up->corkflag;
 979                 break;
 980
 981         case UDP_ENCAP:
 982                 val = up->encap_type;
 983                 break;
 984
 985         default:
 986                 return -ENOPROTOOPT;
 987         };
 988
 989         if(put_user(len, optlen))
 990                 return -EFAULT;
 991         if(copy_to_user(optval, &val,len))
 992                 return -EFAULT;
 993         return 0;
 994 }
 995
 996 static int udpv6_getsockopt(struct sock *sk, int level, int optname,
 997                           char __user *optval, int __user *optlen)
 998 {
 999         if (level != SOL_UDP)
1000                 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1001         return do_udpv6_getsockopt(sk, level, optname, optval, optlen);
1002 }
1003
1004 #ifdef CONFIG_COMPAT
1005 static int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1006                                    char __user *optval, int __user *optlen)
1007 {
1008         if (level != SOL_UDP)
1009                 return compat_ipv6_getsockopt(sk, level, optname,
1010                                               optval, optlen);
1011         return do_udpv6_getsockopt(sk, level, optname, optval, optlen);
1012 }
1013 #endif
1014
1015 static struct inet6_protocol udpv6_protocol = {
1016         .handler        =       udpv6_rcv,
1017         .err_handler    =       udpv6_err,
1018         .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1019 };
1020
1021 /* ------------------------------------------------------------------------ */
1022 #ifdef CONFIG_PROC_FS
1023
1024 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1025 {
1026         struct inet_sock *inet = inet_sk(sp);
1027         struct ipv6_pinfo *np = inet6_sk(sp);
1028         struct in6_addr *dest, *src;
1029         __u16 destp, srcp;
1030
1031         dest  = &np->daddr;
1032         src   = &np->rcv_saddr;
1033         destp = ntohs(inet->dport);
1034         srcp  = ntohs(inet->sport);
1035         seq_printf(seq,
1036                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1037                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p\n",
1038                    bucket,
1039                    src->s6_addr32[0], src->s6_addr32[1],
1040                    src->s6_addr32[2], src->s6_addr32[3], srcp,
1041                    dest->s6_addr32[0], dest->s6_addr32[1],
1042                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
1043                    sp->sk_state,
1044                    atomic_read(&sp->sk_wmem_alloc),
1045                    atomic_read(&sp->sk_rmem_alloc),
1046                    0, 0L, 0,
1047                    sock_i_uid(sp), 0,
1048                    sock_i_ino(sp),
1049                    atomic_read(&sp->sk_refcnt), sp);
1050 }
1051
1052 static int udp6_seq_show(struct seq_file *seq, void *v)
1053 {
1054         if (v == SEQ_START_TOKEN)
1055                 seq_printf(seq,
1056                            "  sl  "
1057                            "local_address                         "
1058                            "remote_address                        "
1059                            "st tx_queue rx_queue tr tm->when retrnsmt"
1060                            "   uid  timeout inode\n");
1061         else
1062                 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1063         return 0;
1064 }
1065
1066 static struct file_operations udp6_seq_fops;
1067 static struct udp_seq_afinfo udp6_seq_afinfo = {
1068         .owner          = THIS_MODULE,
1069         .name           = "udp6",
1070         .family         = AF_INET6,
1071         .seq_show       = udp6_seq_show,
1072         .seq_fops       = &udp6_seq_fops,
1073 };
1074
1075 int __init udp6_proc_init(void)
1076 {
1077         return udp_proc_register(&udp6_seq_afinfo);
1078 }
1079
1080 void udp6_proc_exit(void) {
1081         udp_proc_unregister(&udp6_seq_afinfo);
1082 }
1083 #endif /* CONFIG_PROC_FS */
1084
1085 /* ------------------------------------------------------------------------ */
1086
1087 struct proto udpv6_prot = {
1088         .name              = "UDPv6",
1089         .owner             = THIS_MODULE,
1090         .close             = udpv6_close,
1091         .connect           = ip6_datagram_connect,
1092         .disconnect        = udp_disconnect,
1093         .ioctl             = udp_ioctl,
1094         .destroy           = udpv6_destroy_sock,
1095         .setsockopt        = udpv6_setsockopt,
1096         .getsockopt        = udpv6_getsockopt,
1097         .sendmsg           = udpv6_sendmsg,
1098         .recvmsg           = udpv6_recvmsg,
1099         .backlog_rcv       = udpv6_queue_rcv_skb,
1100         .hash              = udp_v6_hash,
1101         .unhash            = udp_v6_unhash,
1102         .get_port          = udp_v6_get_port,
1103         .obj_size          = sizeof(struct udp6_sock),
1104 #ifdef CONFIG_COMPAT
1105         .compat_setsockopt = compat_udpv6_setsockopt,
1106         .compat_getsockopt = compat_udpv6_getsockopt,
1107 #endif
1108 };
1109
1110 static struct inet_protosw udpv6_protosw = {
1111         .type =      SOCK_DGRAM,
1112         .protocol =  IPPROTO_UDP,
1113         .prot =      &udpv6_prot,
1114         .ops =       &inet6_dgram_ops,
1115         .capability =-1,
1116         .no_check =  UDP_CSUM_DEFAULT,
1117         .flags =     INET_PROTOSW_PERMANENT,
1118 };
1119
1120
1121 void __init udpv6_init(void)
1122 {
1123         if (inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP) < 0)
1124                 printk(KERN_ERR "udpv6_init: Could not register protocol\n");
1125         inet6_register_protosw(&udpv6_protosw);
1126 }