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/inet_common.h>
  53
  54 #include <net/checksum.h>
  55 #include <net/xfrm.h>
  56
  57 #include <linux/proc_fs.h>
  58 #include <linux/seq_file.h>
  59
  60 DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6);
  61
  62 /* Grrr, addr_type already calculated by caller, but I don't want
  63  * to add some silly "cookie" argument to this method just for that.
  64  */
  65 static int udp_v6_get_port(struct sock *sk, unsigned short snum)
  66 {
  67         struct sock *sk2;
  68         struct hlist_node *node;
  69
  70         write_lock_bh(&udp_hash_lock);
  71         if (snum == 0) {
  72                 int best_size_so_far, best, result, i;
  73
  74                 if (udp_port_rover > sysctl_local_port_range[1] ||
  75                     udp_port_rover < sysctl_local_port_range[0])
  76                         udp_port_rover = sysctl_local_port_range[0];
  77                 best_size_so_far = 32767;
  78                 best = result = udp_port_rover;
  79                 for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) {
  80                         int size;
  81                         struct hlist_head *list;
  82
  83                         list = &udp_hash[result & (UDP_HTABLE_SIZE - 1)];
  84                         if (hlist_empty(list)) {
  85                                 if (result > sysctl_local_port_range[1])
  86                                         result = sysctl_local_port_range[0] +
  87                                                 ((result - sysctl_local_port_range[0]) &
  88                                                  (UDP_HTABLE_SIZE - 1));
  89                                 goto gotit;
  90                         }
  91                         size = 0;
  92                         sk_for_each(sk2, node, list)
  93                                 if (++size >= best_size_so_far)
  94                                         goto next;
  95                         best_size_so_far = size;
  96                         best = result;
  97                 next:;
  98                 }
  99                 result = best;
 100                 for(;; result += UDP_HTABLE_SIZE) {
 101                         if (result > sysctl_local_port_range[1])
 102                                 result = sysctl_local_port_range[0]
 103                                         + ((result - sysctl_local_port_range[0]) &
 104                                            (UDP_HTABLE_SIZE - 1));
 105                         if (!udp_lport_inuse(result))
 106                                 break;
 107                 }
 108 gotit:
 109                 udp_port_rover = snum = result;
 110         } else {
 111                 sk_for_each(sk2, node,
 112                             &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]) {
 113                         if (inet_sk(sk2)->num == snum &&
 114                             sk2 != sk &&
 115                             (!sk2->sk_bound_dev_if ||
 116                              !sk->sk_bound_dev_if ||
 117                              sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 118                             (!sk2->sk_reuse || !sk->sk_reuse) &&
 119                             ipv6_rcv_saddr_equal(sk, sk2))
 120                                 goto fail;
 121                 }
 122         }
 123
 124         inet_sk(sk)->num = snum;
 125         if (sk_unhashed(sk)) {
 126                 sk_add_node(sk, &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]);
 127                 sock_prot_inc_use(sk->sk_prot);
 128         }
 129         write_unlock_bh(&udp_hash_lock);
 130         return 0;
 131
 132 fail:
 133         write_unlock_bh(&udp_hash_lock);
 134         return 1;
 135 }
 136
 137 static void udp_v6_hash(struct sock *sk)
 138 {
 139         BUG();
 140 }
 141
 142 static void udp_v6_unhash(struct sock *sk)
 143 {
 144         write_lock_bh(&udp_hash_lock);
 145         if (sk_del_node_init(sk)) {
 146                 inet_sk(sk)->num = 0;
 147                 sock_prot_dec_use(sk->sk_prot);
 148         }
 149         write_unlock_bh(&udp_hash_lock);
 150 }
 151
 152 static struct sock *udp_v6_lookup(struct in6_addr *saddr, u16 sport,
 153                                   struct in6_addr *daddr, u16 dport, int dif)
 154 {
 155         struct sock *sk, *result = NULL;
 156         struct hlist_node *node;
 157         unsigned short hnum = ntohs(dport);
 158         int badness = -1;
 159
 160         read_lock(&udp_hash_lock);
 161         sk_for_each(sk, node, &udp_hash[hnum & (UDP_HTABLE_SIZE - 1)]) {
 162                 struct inet_opt *inet = inet_sk(sk);
 163
 164                 if (inet->num == hnum && sk->sk_family == PF_INET6) {
 165                         struct ipv6_pinfo *np = inet6_sk(sk);
 166                         int score = 0;
 167                         if (inet->dport) {
 168                                 if (inet->dport != sport)
 169                                         continue;
 170                                 score++;
 171                         }
 172                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 173                                 if (ipv6_addr_cmp(&np->rcv_saddr, daddr))
 174                                         continue;
 175                                 score++;
 176                         }
 177                         if (!ipv6_addr_any(&np->daddr)) {
 178                                 if (ipv6_addr_cmp(&np->daddr, saddr))
 179                                         continue;
 180                                 score++;
 181                         }
 182                         if (sk->sk_bound_dev_if) {
 183                                 if (sk->sk_bound_dev_if != dif)
 184                                         continue;
 185                                 score++;
 186                         }
 187                         if(score == 4) {
 188                                 result = sk;
 189                                 break;
 190                         } else if(score > badness) {
 191                                 result = sk;
 192                                 badness = score;
 193                         }
 194                 }
 195         }
 196         if (result)
 197                 sock_hold(result);
 198         read_unlock(&udp_hash_lock);
 199         return result;
 200 }
 201
 202 /*
 203  *
 204  */
 205
 206 int udpv6_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 207 {
 208         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
 209         struct inet_opt         *inet = inet_sk(sk);
 210         struct ipv6_pinfo       *np = inet6_sk(sk);
 211         struct in6_addr         *daddr;
 212         struct dst_entry        *dst;
 213         struct flowi            fl;
 214         struct ip6_flowlabel    *flowlabel = NULL;
 215         int                     addr_type;
 216         int                     err;
 217
 218         if (usin->sin6_family == AF_INET) {
 219                 if (__ipv6_only_sock(sk))
 220                         return -EAFNOSUPPORT;
 221                 err = udp_connect(sk, uaddr, addr_len);
 222                 goto ipv4_connected;
 223         }
 224
 225         if (addr_len < SIN6_LEN_RFC2133)
 226                 return -EINVAL;
 227
 228         if (usin->sin6_family != AF_INET6)
 229                 return -EAFNOSUPPORT;
 230
 231         memset(&fl, 0, sizeof(fl));
 232         if (np->sndflow) {
 233                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
 234                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
 235                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
 236                         if (flowlabel == NULL)
 237                                 return -EINVAL;
 238                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
 239                 }
 240         }
 241
 242         addr_type = ipv6_addr_type(&usin->sin6_addr);
 243
 244         if (addr_type == IPV6_ADDR_ANY) {
 245                 /*
 246                  *      connect to self
 247                  */
 248                 usin->sin6_addr.s6_addr[15] = 0x01;
 249         }
 250
 251         daddr = &usin->sin6_addr;
 252
 253         if (addr_type == IPV6_ADDR_MAPPED) {
 254                 struct sockaddr_in sin;
 255
 256                 if (__ipv6_only_sock(sk)) {
 257                         err = -ENETUNREACH;
 258                         goto out;
 259                 }
 260                 sin.sin_family = AF_INET;
 261                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
 262                 sin.sin_port = usin->sin6_port;
 263
 264                 err = udp_connect(sk, (struct sockaddr*) &sin, sizeof(sin));
 265
 266 ipv4_connected:
 267                 if (err)
 268                         goto out;
 269
 270                 ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
 271
 272                 if (ipv6_addr_any(&np->saddr)) {
 273                         ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
 274                                       inet->saddr);
 275                 }
 276
 277                 if (ipv6_addr_any(&np->rcv_saddr)) {
 278                         ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
 279                                       inet->rcv_saddr);
 280                 }
 281                 goto out;
 282         }
 283
 284         if (addr_type&IPV6_ADDR_LINKLOCAL) {
 285                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 286                     usin->sin6_scope_id) {
 287                         if (sk->sk_bound_dev_if &&
 288                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
 289                                 err = -EINVAL;
 290                                 goto out;
 291                         }
 292                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 293                         if (!sk->sk_bound_dev_if &&
 294                             (addr_type & IPV6_ADDR_MULTICAST))
 295                                 fl.oif = np->mcast_oif;
 296                 }
 297
 298                 /* Connect to link-local address requires an interface */
 299                 if (!sk->sk_bound_dev_if) {
 300                         err = -EINVAL;
 301                         goto out;
 302                 }
 303         }
 304
 305         ipv6_addr_copy(&np->daddr, daddr);
 306         np->flow_label = fl.fl6_flowlabel;
 307
 308         inet->dport = usin->sin6_port;
 309
 310         /*
 311          *      Check for a route to destination an obtain the
 312          *      destination cache for it.
 313          */
 314
 315         fl.proto = IPPROTO_UDP;
 316         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 317         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 318         fl.oif = sk->sk_bound_dev_if;
 319         fl.fl_ip_dport = inet->dport;
 320         fl.fl_ip_sport = inet->sport;
 321
 322         if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
 323                 fl.oif = np->mcast_oif;
 324
 325         if (flowlabel) {
 326                 if (flowlabel->opt && flowlabel->opt->srcrt) {
 327                         struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
 328                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 329                 }
 330         } else if (np->opt && np->opt->srcrt) {
 331                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
 332                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 333         }
 334
 335         err = ip6_dst_lookup(sk, &dst, &fl);
 336         if (err)
 337                 goto out;
 338
 339         /* source address lookup done in ip6_dst_lookup */
 340
 341         if (ipv6_addr_any(&np->saddr))
 342                 ipv6_addr_copy(&np->saddr, &fl.fl6_src);
 343
 344         if (ipv6_addr_any(&np->rcv_saddr)) {
 345                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
 346                 inet->rcv_saddr = LOOPBACK4_IPV6;
 347         }
 348
 349         ip6_dst_store(sk, dst,
 350                       !ipv6_addr_cmp(&fl.fl6_dst, &np->daddr) ?
 351                       &np->daddr : NULL);
 352
 353         sk->sk_state = TCP_ESTABLISHED;
 354 out:
 355         fl6_sock_release(flowlabel);
 356         return err;
 357 }
 358
 359 static void udpv6_close(struct sock *sk, long timeout)
 360 {
 361         inet_sock_release(sk);
 362 }
 363
 364 /*
 365  *      This should be easy, if there is something there we
 366  *      return it, otherwise we block.
 367  */
 368
 369 static int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
 370                   struct msghdr *msg, size_t len,
 371                   int noblock, int flags, int *addr_len)
 372 {
 373         struct ipv6_pinfo *np = inet6_sk(sk);
 374         struct sk_buff *skb;
 375         size_t copied;
 376         int err;
 377
 378         if (addr_len)
 379                 *addr_len=sizeof(struct sockaddr_in6);
 380
 381         if (flags & MSG_ERRQUEUE)
 382                 return ipv6_recv_error(sk, msg, len);
 383
 384 try_again:
 385         skb = skb_recv_datagram(sk, flags, noblock, &err);
 386         if (!skb)
 387                 goto out;
 388
 389         copied = skb->len - sizeof(struct udphdr);
 390         if (copied > len) {
 391                 copied = len;
 392                 msg->msg_flags |= MSG_TRUNC;
 393         }
 394
 395         if (skb->ip_summed==CHECKSUM_UNNECESSARY) {
 396                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 397                                               copied);
 398         } else if (msg->msg_flags&MSG_TRUNC) {
 399                 if ((unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)))
 400                         goto csum_copy_err;
 401                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
 402                                               copied);
 403         } else {
 404                 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
 405                 if (err == -EINVAL)
 406                         goto csum_copy_err;
 407         }
 408         if (err)
 409                 goto out_free;
 410
 411         sock_recv_timestamp(msg, sk, skb);
 412
 413         /* Copy the address. */
 414         if (msg->msg_name) {
 415                 struct sockaddr_in6 *sin6;
 416
 417                 sin6 = (struct sockaddr_in6 *) msg->msg_name;
 418                 sin6->sin6_family = AF_INET6;
 419                 sin6->sin6_port = skb->h.uh->source;
 420                 sin6->sin6_flowinfo = 0;
 421                 sin6->sin6_scope_id = 0;
 422
 423                 if (skb->protocol == htons(ETH_P_IP)) {
 424                         struct inet_opt *inet = inet_sk(sk);
 425
 426                         ipv6_addr_set(&sin6->sin6_addr, 0, 0,
 427                                       htonl(0xffff), skb->nh.iph->saddr);
 428                         if (inet->cmsg_flags)
 429                                 ip_cmsg_recv(msg, skb);
 430                 } else {
 431                         ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
 432
 433                         if (np->rxopt.all)
 434                                 datagram_recv_ctl(sk, msg, skb);
 435                         if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 436                                 sin6->sin6_scope_id = IP6CB(skb)->iif;
 437                 }
 438         }
 439         err = copied;
 440
 441 out_free:
 442         skb_free_datagram(sk, skb);
 443 out:
 444         return err;
 445
 446 csum_copy_err:
 447         /* Clear queue. */
 448         if (flags&MSG_PEEK) {
 449                 int clear = 0;
 450                 spin_lock_irq(&sk->sk_receive_queue.lock);
 451                 if (skb == skb_peek(&sk->sk_receive_queue)) {
 452                         __skb_unlink(skb, &sk->sk_receive_queue);
 453                         clear = 1;
 454                 }
 455                 spin_unlock_irq(&sk->sk_receive_queue.lock);
 456                 if (clear)
 457                         kfree_skb(skb);
 458         }
 459
 460         skb_free_datagram(sk, skb);
 461
 462         if (flags & MSG_DONTWAIT) {
 463                 UDP6_INC_STATS_USER(UdpInErrors);
 464                 return -EAGAIN;
 465         }
 466         goto try_again;
 467 }
 468
 469 static void udpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 470                int type, int code, int offset, __u32 info)
 471 {
 472         struct ipv6_pinfo *np;
 473         struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
 474         struct net_device *dev = skb->dev;
 475         struct in6_addr *saddr = &hdr->saddr;
 476         struct in6_addr *daddr = &hdr->daddr;
 477         struct udphdr *uh = (struct udphdr*)(skb->data+offset);
 478         struct sock *sk;
 479         int err;
 480
 481         sk = udp_v6_lookup(daddr, uh->dest, saddr, uh->source, dev->ifindex);
 482
 483         if (sk == NULL)
 484                 return;
 485
 486         np = inet6_sk(sk);
 487
 488         if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
 489                 goto out;
 490
 491         if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
 492                 goto out;
 493
 494         if (np->recverr)
 495                 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
 496
 497         sk->sk_err = err;
 498         sk->sk_error_report(sk);
 499 out:
 500         sock_put(sk);
 501 }
 502
 503 static inline int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
 504 {
 505         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
 506                 kfree_skb(skb);
 507                 return -1;
 508         }
 509
 510         if (sk->sk_filter && skb->ip_summed != CHECKSUM_UNNECESSARY) {
 511                 if ((unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum))) {
 512                         UDP6_INC_STATS_BH(UdpInErrors);
 513                         kfree_skb(skb);
 514                         return 0;
 515                 }
 516                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 517         }
 518
 519         if (sock_queue_rcv_skb(sk,skb)<0) {
 520                 UDP6_INC_STATS_BH(UdpInErrors);
 521                 kfree_skb(skb);
 522                 return 0;
 523         }
 524         UDP6_INC_STATS_BH(UdpInDatagrams);
 525         return 0;
 526 }
 527
 528 static struct sock *udp_v6_mcast_next(struct sock *sk,
 529                                       u16 loc_port, struct in6_addr *loc_addr,
 530                                       u16 rmt_port, struct in6_addr *rmt_addr,
 531                                       int dif)
 532 {
 533         struct hlist_node *node;
 534         struct sock *s = sk;
 535         unsigned short num = ntohs(loc_port);
 536
 537         sk_for_each_from(s, node) {
 538                 struct inet_opt *inet = inet_sk(s);
 539
 540                 if (inet->num == num && s->sk_family == PF_INET6) {
 541                         struct ipv6_pinfo *np = inet6_sk(s);
 542                         if (inet->dport) {
 543                                 if (inet->dport != rmt_port)
 544                                         continue;
 545                         }
 546                         if (!ipv6_addr_any(&np->daddr) &&
 547                             ipv6_addr_cmp(&np->daddr, rmt_addr))
 548                                 continue;
 549
 550                         if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
 551                                 continue;
 552
 553                         if (!ipv6_addr_any(&np->rcv_saddr)) {
 554                                 if (!ipv6_addr_cmp(&np->rcv_saddr, loc_addr))
 555                                         return s;
 556                                 continue;
 557                         }
 558                         if(!inet6_mc_check(s, loc_addr, rmt_addr))
 559                                 continue;
 560                         return s;
 561                 }
 562         }
 563         return NULL;
 564 }
 565
 566 /*
 567  * Note: called only from the BH handler context,
 568  * so we don't need to lock the hashes.
 569  */
 570 static void udpv6_mcast_deliver(struct udphdr *uh,
 571                                 struct in6_addr *saddr, struct in6_addr *daddr,
 572                                 struct sk_buff *skb)
 573 {
 574         struct sock *sk, *sk2;
 575         int dif;
 576
 577         read_lock(&udp_hash_lock);
 578         sk = sk_head(&udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]);
 579         dif = skb->dev->ifindex;
 580         sk = udp_v6_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif);
 581         if (!sk) {
 582                 kfree_skb(skb);
 583                 goto out;
 584         }
 585
 586         sk2 = sk;
 587         while ((sk2 = udp_v6_mcast_next(sk_next(sk2), uh->dest, daddr,
 588                                         uh->source, saddr, dif))) {
 589                 struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC);
 590                 if (buff)
 591                         udpv6_queue_rcv_skb(sk2, buff);
 592         }
 593         udpv6_queue_rcv_skb(sk, skb);
 594 out:
 595         read_unlock(&udp_hash_lock);
 596 }
 597
 598 static int udpv6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
 599 {
 600         struct sk_buff *skb = *pskb;
 601         struct sock *sk;
 602         struct udphdr *uh;
 603         struct net_device *dev = skb->dev;
 604         struct in6_addr *saddr, *daddr;
 605         u32 ulen = 0;
 606
 607         if (!pskb_may_pull(skb, sizeof(struct udphdr)))
 608                 goto short_packet;
 609
 610         saddr = &skb->nh.ipv6h->saddr;
 611         daddr = &skb->nh.ipv6h->daddr;
 612         uh = skb->h.uh;
 613
 614         ulen = ntohs(uh->len);
 615
 616         /* Check for jumbo payload */
 617         if (ulen == 0)
 618                 ulen = skb->len;
 619
 620         if (ulen > skb->len || ulen < sizeof(*uh))
 621                 goto short_packet;
 622
 623         if (uh->check == 0) {
 624                 /* RFC 2460 section 8.1 says that we SHOULD log
 625                    this error. Well, it is reasonable.
 626                  */
 627                 LIMIT_NETDEBUG(
 628                         printk(KERN_INFO "IPv6: udp checksum is 0\n"));
 629                 goto discard;
 630         }
 631
 632         if (ulen < skb->len) {
 633                 if (__pskb_trim(skb, ulen))
 634                         goto discard;
 635                 saddr = &skb->nh.ipv6h->saddr;
 636                 daddr = &skb->nh.ipv6h->daddr;
 637                 uh = skb->h.uh;
 638         }
 639
 640         if (skb->ip_summed==CHECKSUM_HW) {
 641                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 642                 if (csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, skb->csum)) {
 643                         LIMIT_NETDEBUG(printk(KERN_DEBUG "udp v6 hw csum failure.\n"));
 644                         skb->ip_summed = CHECKSUM_NONE;
 645                 }
 646         }
 647         if (skb->ip_summed != CHECKSUM_UNNECESSARY)
 648                 skb->csum = ~csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, 0);
 649
 650         /*
 651          *      Multicast receive code
 652          */
 653         if (ipv6_addr_is_multicast(daddr)) {
 654                 udpv6_mcast_deliver(uh, saddr, daddr, skb);
 655                 return 0;
 656         }
 657
 658         /* Unicast */
 659
 660         /*
 661          * check socket cache ... must talk to Alan about his plans
 662          * for sock caches... i'll skip this for now.
 663          */
 664         sk = udp_v6_lookup(saddr, uh->source, daddr, uh->dest, dev->ifindex);
 665
 666         if (sk == NULL) {
 667                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 668                         goto discard;
 669
 670                 if (skb->ip_summed != CHECKSUM_UNNECESSARY &&
 671                     (unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)))
 672                         goto discard;
 673                 UDP6_INC_STATS_BH(UdpNoPorts);
 674
 675                 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0, dev);
 676
 677                 kfree_skb(skb);
 678                 return(0);
 679         }
 680
 681         /* deliver */
 682
 683         udpv6_queue_rcv_skb(sk, skb);
 684         sock_put(sk);
 685         return(0);
 686
 687 short_packet:
 688         if (net_ratelimit())
 689                 printk(KERN_DEBUG "UDP: short packet: %d/%u\n", ulen, skb->len);
 690
 691 discard:
 692         UDP6_INC_STATS_BH(UdpInErrors);
 693         kfree_skb(skb);
 694         return(0);
 695 }
 696 /*
 697  * Throw away all pending data and cancel the corking. Socket is locked.
 698  */
 699 static void udp_v6_flush_pending_frames(struct sock *sk)
 700 {
 701         struct udp_opt *up = udp_sk(sk);
 702
 703         if (up->pending) {
 704                 up->len = 0;
 705                 up->pending = 0;
 706                 ip6_flush_pending_frames(sk);
 707         }
 708 }
 709
 710 /*
 711  *      Sending
 712  */
 713
 714 static int udp_v6_push_pending_frames(struct sock *sk, struct udp_opt *up)
 715 {
 716         struct sk_buff *skb;
 717         struct udphdr *uh;
 718         struct inet_opt *inet = inet_sk(sk);
 719         struct flowi *fl = &inet->cork.fl;
 720         int err = 0;
 721
 722         /* Grab the skbuff where UDP header space exists. */
 723         if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
 724                 goto out;
 725
 726         /*
 727          * Create a UDP header
 728          */
 729         uh = skb->h.uh;
 730         uh->source = fl->fl_ip_sport;
 731         uh->dest = fl->fl_ip_dport;
 732         uh->len = htons(up->len);
 733         uh->check = 0;
 734
 735         if (sk->sk_no_check == UDP_CSUM_NOXMIT) {
 736                 skb->ip_summed = CHECKSUM_NONE;
 737                 goto send;
 738         }
 739
 740         if (skb_queue_len(&sk->sk_write_queue) == 1) {
 741                 skb->csum = csum_partial((char *)uh,
 742                                 sizeof(struct udphdr), skb->csum);
 743                 uh->check = csum_ipv6_magic(&fl->fl6_src,
 744                                             &fl->fl6_dst,
 745                                             up->len, fl->proto, skb->csum);
 746         } else {
 747                 u32 tmp_csum = 0;
 748
 749                 skb_queue_walk(&sk->sk_write_queue, skb) {
 750                         tmp_csum = csum_add(tmp_csum, skb->csum);
 751                 }
 752                 tmp_csum = csum_partial((char *)uh,
 753                                 sizeof(struct udphdr), tmp_csum);
 754                 tmp_csum = csum_ipv6_magic(&fl->fl6_src,
 755                                            &fl->fl6_dst,
 756                                            up->len, fl->proto, tmp_csum);
 757                 uh->check = tmp_csum;
 758
 759         }
 760         if (uh->check == 0)
 761                 uh->check = -1;
 762
 763 send:
 764         err = ip6_push_pending_frames(sk);
 765 out:
 766         up->len = 0;
 767         up->pending = 0;
 768         return err;
 769 }
 770
 771 static int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
 772                   struct msghdr *msg, size_t len)
 773 {
 774         struct ipv6_txoptions opt_space;
 775         struct udp_opt *up = udp_sk(sk);
 776         struct inet_opt *inet = inet_sk(sk);
 777         struct ipv6_pinfo *np = inet6_sk(sk);
 778         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
 779         struct in6_addr *daddr;
 780         struct ipv6_txoptions *opt = NULL;
 781         struct ip6_flowlabel *flowlabel = NULL;
 782         struct flowi *fl = &inet->cork.fl;
 783         struct dst_entry *dst;
 784         int addr_len = msg->msg_namelen;
 785         int ulen = len;
 786         int hlimit = -1;
 787         int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
 788         int err;
 789
 790         /* destination address check */
 791         if (sin6) {
 792                 if (addr_len < offsetof(struct sockaddr, sa_data))
 793                         return -EINVAL;
 794
 795                 switch (sin6->sin6_family) {
 796                 case AF_INET6:
 797                         if (addr_len < SIN6_LEN_RFC2133)
 798                                 return -EINVAL;
 799                         daddr = &sin6->sin6_addr;
 800                         break;
 801                 case AF_INET:
 802                         goto do_udp_sendmsg;
 803                 case AF_UNSPEC:
 804                         msg->msg_name = sin6 = NULL;
 805                         msg->msg_namelen = addr_len = 0;
 806                         daddr = NULL;
 807                         break;
 808                 default:
 809                         return -EINVAL;
 810                 }
 811         } else if (!up->pending) {
 812                 if (sk->sk_state != TCP_ESTABLISHED)
 813                         return -EDESTADDRREQ;
 814                 daddr = &np->daddr;
 815         } else
 816                 daddr = NULL;
 817
 818         if (daddr) {
 819                 if (ipv6_addr_type(daddr) == IPV6_ADDR_MAPPED) {
 820                         struct sockaddr_in sin;
 821                         sin.sin_family = AF_INET;
 822                         sin.sin_port = sin6 ? sin6->sin6_port : inet->dport;
 823                         sin.sin_addr.s_addr = daddr->s6_addr32[3];
 824                         msg->msg_name = &sin;
 825                         msg->msg_namelen = sizeof(sin);
 826 do_udp_sendmsg:
 827                         if (__ipv6_only_sock(sk))
 828                                 return -ENETUNREACH;
 829                         return udp_sendmsg(iocb, sk, msg, len);
 830                 }
 831         }
 832
 833         if (up->pending == AF_INET)
 834                 return udp_sendmsg(iocb, sk, msg, len);
 835
 836         /* Rough check on arithmetic overflow,
 837            better check is made in ip6_build_xmit
 838            */
 839         if (len > INT_MAX - sizeof(struct udphdr))
 840                 return -EMSGSIZE;
 841
 842         if (up->pending) {
 843                 /*
 844                  * There are pending frames.
 845                  * The socket lock must be held while it's corked.
 846                  */
 847                 lock_sock(sk);
 848                 if (likely(up->pending)) {
 849                         if (unlikely(up->pending != AF_INET6)) {
 850                                 release_sock(sk);
 851                                 return -EINVAL;
 852                         }
 853                         dst = NULL;
 854                         goto do_append_data;
 855                 }
 856                 release_sock(sk);
 857         }
 858         ulen += sizeof(struct udphdr);
 859
 860         memset(fl, 0, sizeof(*fl));
 861
 862         if (sin6) {
 863                 if (sin6->sin6_port == 0)
 864                         return -EINVAL;
 865
 866                 fl->fl_ip_dport = sin6->sin6_port;
 867                 daddr = &sin6->sin6_addr;
 868
 869                 if (np->sndflow) {
 870                         fl->fl6_flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
 871                         if (fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
 872                                 flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 873                                 if (flowlabel == NULL)
 874                                         return -EINVAL;
 875                                 daddr = &flowlabel->dst;
 876                         }
 877                 }
 878
 879                 /*
 880                  * Otherwise it will be difficult to maintain
 881                  * sk->sk_dst_cache.
 882                  */
 883                 if (sk->sk_state == TCP_ESTABLISHED &&
 884                     !ipv6_addr_cmp(daddr, &np->daddr))
 885                         daddr = &np->daddr;
 886
 887                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 888                     sin6->sin6_scope_id &&
 889                     ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
 890                         fl->oif = sin6->sin6_scope_id;
 891         } else {
 892                 if (sk->sk_state != TCP_ESTABLISHED)
 893                         return -EDESTADDRREQ;
 894
 895                 fl->fl_ip_dport = inet->dport;
 896                 daddr = &np->daddr;
 897                 fl->fl6_flowlabel = np->flow_label;
 898         }
 899
 900         if (!fl->oif)
 901                 fl->oif = sk->sk_bound_dev_if;
 902
 903         if (msg->msg_controllen) {
 904                 opt = &opt_space;
 905                 memset(opt, 0, sizeof(struct ipv6_txoptions));
 906                 opt->tot_len = sizeof(*opt);
 907
 908                 err = datagram_send_ctl(msg, fl, opt, &hlimit);
 909                 if (err < 0) {
 910                         fl6_sock_release(flowlabel);
 911                         return err;
 912                 }
 913                 if ((fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
 914                         flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
 915                         if (flowlabel == NULL)
 916                                 return -EINVAL;
 917                 }
 918                 if (!(opt->opt_nflen|opt->opt_flen))
 919                         opt = NULL;
 920         }
 921         if (opt == NULL)
 922                 opt = np->opt;
 923         if (flowlabel)
 924                 opt = fl6_merge_options(&opt_space, flowlabel, opt);
 925
 926         fl->proto = IPPROTO_UDP;
 927         ipv6_addr_copy(&fl->fl6_dst, daddr);
 928         if (ipv6_addr_any(&fl->fl6_src) && !ipv6_addr_any(&np->saddr))
 929                 ipv6_addr_copy(&fl->fl6_src, &np->saddr);
 930         fl->fl_ip_sport = inet->sport;
 931
 932         /* merge ip6_build_xmit from ip6_output */
 933         if (opt && opt->srcrt) {
 934                 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
 935                 ipv6_addr_copy(&fl->fl6_dst, rt0->addr);
 936         }
 937
 938         if (!fl->oif && ipv6_addr_is_multicast(&fl->fl6_dst))
 939                 fl->oif = np->mcast_oif;
 940
 941         err = ip6_dst_lookup(sk, &dst, fl);
 942         if (err)
 943                 goto out;
 944
 945         if (hlimit < 0) {
 946                 if (ipv6_addr_is_multicast(&fl->fl6_dst))
 947                         hlimit = np->mcast_hops;
 948                 else
 949                         hlimit = np->hop_limit;
 950                 if (hlimit < 0)
 951                         hlimit = dst_metric(dst, RTAX_HOPLIMIT);
 952         }
 953
 954         if (msg->msg_flags&MSG_CONFIRM)
 955                 goto do_confirm;
 956 back_from_confirm:
 957
 958         lock_sock(sk);
 959         if (unlikely(up->pending)) {
 960                 /* The socket is already corked while preparing it. */
 961                 /* ... which is an evident application bug. --ANK */
 962                 release_sock(sk);
 963
 964                 LIMIT_NETDEBUG(printk(KERN_DEBUG "udp cork app bug 2\n"));
 965                 err = -EINVAL;
 966                 goto out;
 967         }
 968
 969         up->pending = AF_INET6;
 970
 971 do_append_data:
 972         up->len += ulen;
 973         err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov, ulen, sizeof(struct udphdr),
 974                               hlimit, opt, fl, (struct rt6_info*)dst,
 975                               corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
 976         if (err)
 977                 udp_v6_flush_pending_frames(sk);
 978         else if (!corkreq)
 979                 err = udp_v6_push_pending_frames(sk, up);
 980
 981         if (dst)
 982                 ip6_dst_store(sk, dst,
 983                               !ipv6_addr_cmp(&fl->fl6_dst, &np->daddr) ?
 984                               &np->daddr : NULL);
 985         if (err > 0)
 986                 err = np->recverr ? net_xmit_errno(err) : 0;
 987         release_sock(sk);
 988 out:
 989         fl6_sock_release(flowlabel);
 990         if (!err) {
 991                 UDP6_INC_STATS_USER(UdpOutDatagrams);
 992                 return len;
 993         }
 994         return err;
 995
 996 do_confirm:
 997         dst_confirm(dst);
 998         if (!(msg->msg_flags&MSG_PROBE) || len)
 999                 goto back_from_confirm;
1000         err = 0;
1001         goto out;
1002 }
1003
1004 static int udpv6_destroy_sock(struct sock *sk)
1005 {
1006         lock_sock(sk);
1007         udp_v6_flush_pending_frames(sk);
1008         release_sock(sk);
1009
1010         inet6_destroy_sock(sk);
1011
1012         return 0;
1013 }
1014
1015 /*
1016  *      Socket option code for UDP
1017  */
1018 static int udpv6_setsockopt(struct sock *sk, int level, int optname,
1019                           char __user *optval, int optlen)
1020 {
1021         struct udp_opt *up = udp_sk(sk);
1022         int val;
1023         int err = 0;
1024
1025         if (level != SOL_UDP)
1026                 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1027
1028         if(optlen<sizeof(int))
1029                 return -EINVAL;
1030
1031         if (get_user(val, (int __user *)optval))
1032                 return -EFAULT;
1033
1034         switch(optname) {
1035         case UDP_CORK:
1036                 if (val != 0) {
1037                         up->corkflag = 1;
1038                 } else {
1039                         up->corkflag = 0;
1040                         lock_sock(sk);
1041                         udp_v6_push_pending_frames(sk, up);
1042                         release_sock(sk);
1043                 }
1044                 break;
1045
1046         case UDP_ENCAP:
1047                 up->encap_type = val;
1048                 break;
1049
1050         default:
1051                 err = -ENOPROTOOPT;
1052                 break;
1053         };
1054
1055         return err;
1056 }
1057
1058 static int udpv6_getsockopt(struct sock *sk, int level, int optname,
1059                           char __user *optval, int __user *optlen)
1060 {
1061         struct udp_opt *up = udp_sk(sk);
1062         int val, len;
1063
1064         if (level != SOL_UDP)
1065                 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1066
1067         if(get_user(len,optlen))
1068                 return -EFAULT;
1069
1070         len = min_t(unsigned int, len, sizeof(int));
1071
1072         if(len < 0)
1073                 return -EINVAL;
1074
1075         switch(optname) {
1076         case UDP_CORK:
1077                 val = up->corkflag;
1078                 break;
1079
1080         case UDP_ENCAP:
1081                 val = up->encap_type;
1082                 break;
1083
1084         default:
1085                 return -ENOPROTOOPT;
1086         };
1087
1088         if(put_user(len, optlen))
1089                 return -EFAULT;
1090         if(copy_to_user(optval, &val,len))
1091                 return -EFAULT;
1092         return 0;
1093 }
1094
1095 static struct inet6_protocol udpv6_protocol = {
1096         .handler        =       udpv6_rcv,
1097         .err_handler    =       udpv6_err,
1098         .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1099 };
1100
1101 /* ------------------------------------------------------------------------ */
1102 #ifdef CONFIG_PROC_FS
1103
1104 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1105 {
1106         struct inet_opt *inet = inet_sk(sp);
1107         struct ipv6_pinfo *np = inet6_sk(sp);
1108         struct in6_addr *dest, *src;
1109         __u16 destp, srcp;
1110
1111         dest  = &np->daddr;
1112         src   = &np->rcv_saddr;
1113         destp = ntohs(inet->dport);
1114         srcp  = ntohs(inet->sport);
1115         seq_printf(seq,
1116                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1117                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p\n",
1118                    bucket,
1119                    src->s6_addr32[0], src->s6_addr32[1],
1120                    src->s6_addr32[2], src->s6_addr32[3], srcp,
1121                    dest->s6_addr32[0], dest->s6_addr32[1],
1122                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
1123                    sp->sk_state,
1124                    atomic_read(&sp->sk_wmem_alloc),
1125                    atomic_read(&sp->sk_rmem_alloc),
1126                    0, 0L, 0,
1127                    sock_i_uid(sp), 0,
1128                    sock_i_ino(sp),
1129                    atomic_read(&sp->sk_refcnt), sp);
1130 }
1131
1132 static int udp6_seq_show(struct seq_file *seq, void *v)
1133 {
1134         if (v == SEQ_START_TOKEN)
1135                 seq_printf(seq,
1136                            "  sl  "
1137                            "local_address                         "
1138                            "remote_address                        "
1139                            "st tx_queue rx_queue tr tm->when retrnsmt"
1140                            "   uid  timeout inode\n");
1141         else
1142                 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1143         return 0;
1144 }
1145
1146 static struct file_operations udp6_seq_fops;
1147 static struct udp_seq_afinfo udp6_seq_afinfo = {
1148         .owner          = THIS_MODULE,
1149         .name           = "udp6",
1150         .family         = AF_INET6,
1151         .seq_show       = udp6_seq_show,
1152         .seq_fops       = &udp6_seq_fops,
1153 };
1154
1155 int __init udp6_proc_init(void)
1156 {
1157         return udp_proc_register(&udp6_seq_afinfo);
1158 }
1159
1160 void udp6_proc_exit(void) {
1161         udp_proc_unregister(&udp6_seq_afinfo);
1162 }
1163 #endif /* CONFIG_PROC_FS */
1164
1165 /* ------------------------------------------------------------------------ */
1166
1167 struct proto udpv6_prot = {
1168         .name =         "UDP",
1169         .close =        udpv6_close,
1170         .connect =      udpv6_connect,
1171         .disconnect =   udp_disconnect,
1172         .ioctl =        udp_ioctl,
1173         .destroy =      udpv6_destroy_sock,
1174         .setsockopt =   udpv6_setsockopt,
1175         .getsockopt =   udpv6_getsockopt,
1176         .sendmsg =      udpv6_sendmsg,
1177         .recvmsg =      udpv6_recvmsg,
1178         .backlog_rcv =  udpv6_queue_rcv_skb,
1179         .hash =         udp_v6_hash,
1180         .unhash =       udp_v6_unhash,
1181         .get_port =     udp_v6_get_port,
1182 };
1183
1184 extern struct proto_ops inet6_dgram_ops;
1185
1186 static struct inet_protosw udpv6_protosw = {
1187         .type =      SOCK_DGRAM,
1188         .protocol =  IPPROTO_UDP,
1189         .prot =      &udpv6_prot,
1190         .ops =       &inet6_dgram_ops,
1191         .capability =-1,
1192         .no_check =  UDP_CSUM_DEFAULT,
1193         .flags =     INET_PROTOSW_PERMANENT,
1194 };
1195
1196
1197 void __init udpv6_init(void)
1198 {
1199         if (inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP) < 0)
1200                 printk(KERN_ERR "udpv6_init: Could not register protocol\n");
1201         inet6_register_protosw(&udpv6_protosw);
1202 }