[IPV6]: Fix per-socket multicast filtering in sk_reuse case
[linux-3.10.git] / net / ipv6 / udp.c
1 /*
2  *      UDP over IPv6
3  *      Linux INET6 implementation 
4  *
5  *      Authors:
6  *      Pedro Roque             <roque@di.fc.ul.pt>     
7  *
8  *      Based on linux/ipv4/udp.c
9  *
10  *      $Id: udp.c,v 1.65 2002/02/01 22:01:04 davem Exp $
11  *
12  *      Fixes:
13  *      Hideaki YOSHIFUJI       :       sin6_scope_id support
14  *      YOSHIFUJI Hideaki @USAGI and:   Support IPV6_V6ONLY socket option, which
15  *      Alexey Kuznetsov                allow both IPv4 and IPv6 sockets to bind
16  *                                      a single port at the same time.
17  *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
18  *      YOSHIFUJI Hideaki @USAGI:       convert /proc/net/udp6 to seq_file.
19  *
20  *      This program is free software; you can redistribute it and/or
21  *      modify it under the terms of the GNU General Public License
22  *      as published by the Free Software Foundation; either version
23  *      2 of the License, or (at your option) any later version.
24  */
25
26 #include <linux/config.h>
27 #include <linux/errno.h>
28 #include <linux/types.h>
29 #include <linux/socket.h>
30 #include <linux/sockios.h>
31 #include <linux/sched.h>
32 #include <linux/net.h>
33 #include <linux/in6.h>
34 #include <linux/netdevice.h>
35 #include <linux/if_arp.h>
36 #include <linux/ipv6.h>
37 #include <linux/icmpv6.h>
38 #include <linux/init.h>
39 #include <asm/uaccess.h>
40
41 #include <net/sock.h>
42 #include <net/snmp.h>
43
44 #include <net/ipv6.h>
45 #include <net/ndisc.h>
46 #include <net/protocol.h>
47 #include <net/transp_v6.h>
48 #include <net/ip6_route.h>
49 #include <net/addrconf.h>
50 #include <net/ip.h>
51 #include <net/udp.h>
52 #include <net/raw.h>
53 #include <net/inet_common.h>
54 #include <net/tcp_states.h>
55
56 #include <net/ip6_checksum.h>
57 #include <net/xfrm.h>
58
59 #include <linux/proc_fs.h>
60 #include <linux/seq_file.h>
61
62 DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6) __read_mostly;
63
64 /* Grrr, addr_type already calculated by caller, but I don't want
65  * to add some silly "cookie" argument to this method just for that.
66  */
67 static int udp_v6_get_port(struct sock *sk, unsigned short snum)
68 {
69         struct sock *sk2;
70         struct hlist_node *node;
71
72         write_lock_bh(&udp_hash_lock);
73         if (snum == 0) {
74                 int best_size_so_far, best, result, i;
75
76                 if (udp_port_rover > sysctl_local_port_range[1] ||
77                     udp_port_rover < sysctl_local_port_range[0])
78                         udp_port_rover = sysctl_local_port_range[0];
79                 best_size_so_far = 32767;
80                 best = result = udp_port_rover;
81                 for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) {
82                         int size;
83                         struct hlist_head *list;
84
85                         list = &udp_hash[result & (UDP_HTABLE_SIZE - 1)];
86                         if (hlist_empty(list)) {
87                                 if (result > sysctl_local_port_range[1])
88                                         result = sysctl_local_port_range[0] +
89                                                 ((result - sysctl_local_port_range[0]) &
90                                                  (UDP_HTABLE_SIZE - 1));
91                                 goto gotit;
92                         }
93                         size = 0;
94                         sk_for_each(sk2, node, list)
95                                 if (++size >= best_size_so_far)
96                                         goto next;
97                         best_size_so_far = size;
98                         best = result;
99                 next:;
100                 }
101                 result = best;
102                 for(;; result += UDP_HTABLE_SIZE) {
103                         if (result > sysctl_local_port_range[1])
104                                 result = sysctl_local_port_range[0]
105                                         + ((result - sysctl_local_port_range[0]) &
106                                            (UDP_HTABLE_SIZE - 1));
107                         if (!udp_lport_inuse(result))
108                                 break;
109                 }
110 gotit:
111                 udp_port_rover = snum = result;
112         } else {
113                 sk_for_each(sk2, node,
114                             &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]) {
115                         if (inet_sk(sk2)->num == snum &&
116                             sk2 != sk &&
117                             (!sk2->sk_bound_dev_if ||
118                              !sk->sk_bound_dev_if ||
119                              sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
120                             (!sk2->sk_reuse || !sk->sk_reuse) &&
121                             ipv6_rcv_saddr_equal(sk, sk2))
122                                 goto fail;
123                 }
124         }
125
126         inet_sk(sk)->num = snum;
127         if (sk_unhashed(sk)) {
128                 sk_add_node(sk, &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]);
129                 sock_prot_inc_use(sk->sk_prot);
130         }
131         write_unlock_bh(&udp_hash_lock);
132         return 0;
133
134 fail:
135         write_unlock_bh(&udp_hash_lock);
136         return 1;
137 }
138
139 static void udp_v6_hash(struct sock *sk)
140 {
141         BUG();
142 }
143
144 static void udp_v6_unhash(struct sock *sk)
145 {
146         write_lock_bh(&udp_hash_lock);
147         if (sk_del_node_init(sk)) {
148                 inet_sk(sk)->num = 0;
149                 sock_prot_dec_use(sk->sk_prot);
150         }
151         write_unlock_bh(&udp_hash_lock);
152 }
153
154 static struct sock *udp_v6_lookup(struct in6_addr *saddr, u16 sport,
155                                   struct in6_addr *daddr, u16 dport, int dif)
156 {
157         struct sock *sk, *result = NULL;
158         struct hlist_node *node;
159         unsigned short hnum = ntohs(dport);
160         int badness = -1;
161
162         read_lock(&udp_hash_lock);
163         sk_for_each(sk, node, &udp_hash[hnum & (UDP_HTABLE_SIZE - 1)]) {
164                 struct inet_sock *inet = inet_sk(sk);
165
166                 if (inet->num == hnum && sk->sk_family == PF_INET6) {
167                         struct ipv6_pinfo *np = inet6_sk(sk);
168                         int score = 0;
169                         if (inet->dport) {
170                                 if (inet->dport != sport)
171                                         continue;
172                                 score++;
173                         }
174                         if (!ipv6_addr_any(&np->rcv_saddr)) {
175                                 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
176                                         continue;
177                                 score++;
178                         }
179                         if (!ipv6_addr_any(&np->daddr)) {
180                                 if (!ipv6_addr_equal(&np->daddr, saddr))
181                                         continue;
182                                 score++;
183                         }
184                         if (sk->sk_bound_dev_if) {
185                                 if (sk->sk_bound_dev_if != dif)
186                                         continue;
187                                 score++;
188                         }
189                         if(score == 4) {
190                                 result = sk;
191                                 break;
192                         } else if(score > badness) {
193                                 result = sk;
194                                 badness = score;
195                         }
196                 }
197         }
198         if (result)
199                 sock_hold(result);
200         read_unlock(&udp_hash_lock);
201         return result;
202 }
203
204 /*
205  *
206  */
207
208 static void udpv6_close(struct sock *sk, long timeout)
209 {
210         sk_common_release(sk);
211 }
212
213 /*
214  *      This should be easy, if there is something there we
215  *      return it, otherwise we block.
216  */
217
218 static int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk, 
219                   struct msghdr *msg, size_t len,
220                   int noblock, int flags, int *addr_len)
221 {
222         struct ipv6_pinfo *np = inet6_sk(sk);
223         struct inet_sock *inet = inet_sk(sk);
224         struct sk_buff *skb;
225         size_t copied;
226         int err;
227
228         if (addr_len)
229                 *addr_len=sizeof(struct sockaddr_in6);
230   
231         if (flags & MSG_ERRQUEUE)
232                 return ipv6_recv_error(sk, msg, len);
233
234 try_again:
235         skb = skb_recv_datagram(sk, flags, noblock, &err);
236         if (!skb)
237                 goto out;
238
239         copied = skb->len - sizeof(struct udphdr);
240         if (copied > len) {
241                 copied = len;
242                 msg->msg_flags |= MSG_TRUNC;
243         }
244
245         if (skb->ip_summed==CHECKSUM_UNNECESSARY) {
246                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
247                                               copied);
248         } else if (msg->msg_flags&MSG_TRUNC) {
249                 if ((unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)))
250                         goto csum_copy_err;
251                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
252                                               copied);
253         } else {
254                 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
255                 if (err == -EINVAL)
256                         goto csum_copy_err;
257         }
258         if (err)
259                 goto out_free;
260
261         sock_recv_timestamp(msg, sk, skb);
262
263         /* Copy the address. */
264         if (msg->msg_name) {
265                 struct sockaddr_in6 *sin6;
266           
267                 sin6 = (struct sockaddr_in6 *) msg->msg_name;
268                 sin6->sin6_family = AF_INET6;
269                 sin6->sin6_port = skb->h.uh->source;
270                 sin6->sin6_flowinfo = 0;
271                 sin6->sin6_scope_id = 0;
272
273                 if (skb->protocol == htons(ETH_P_IP))
274                         ipv6_addr_set(&sin6->sin6_addr, 0, 0,
275                                       htonl(0xffff), skb->nh.iph->saddr);
276                 else {
277                         ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
278                         if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
279                                 sin6->sin6_scope_id = IP6CB(skb)->iif;
280                 }
281
282         }
283         if (skb->protocol == htons(ETH_P_IP)) {
284                 if (inet->cmsg_flags)
285                         ip_cmsg_recv(msg, skb);
286         } else {
287                 if (np->rxopt.all)
288                         datagram_recv_ctl(sk, msg, skb);
289         }
290
291         err = copied;
292         if (flags & MSG_TRUNC)
293                 err = skb->len - sizeof(struct udphdr);
294
295 out_free:
296         skb_free_datagram(sk, skb);
297 out:
298         return err;
299
300 csum_copy_err:
301         /* Clear queue. */
302         if (flags&MSG_PEEK) {
303                 int clear = 0;
304                 spin_lock_bh(&sk->sk_receive_queue.lock);
305                 if (skb == skb_peek(&sk->sk_receive_queue)) {
306                         __skb_unlink(skb, &sk->sk_receive_queue);
307                         clear = 1;
308                 }
309                 spin_unlock_bh(&sk->sk_receive_queue.lock);
310                 if (clear)
311                         kfree_skb(skb);
312         }
313
314         skb_free_datagram(sk, skb);
315
316         if (flags & MSG_DONTWAIT) {
317                 UDP6_INC_STATS_USER(UDP_MIB_INERRORS);
318                 return -EAGAIN;
319         }
320         goto try_again;
321 }
322
323 static void udpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
324                int type, int code, int offset, __u32 info)
325 {
326         struct ipv6_pinfo *np;
327         struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
328         struct net_device *dev = skb->dev;
329         struct in6_addr *saddr = &hdr->saddr;
330         struct in6_addr *daddr = &hdr->daddr;
331         struct udphdr *uh = (struct udphdr*)(skb->data+offset);
332         struct sock *sk;
333         int err;
334
335         sk = udp_v6_lookup(daddr, uh->dest, saddr, uh->source, dev->ifindex);
336    
337         if (sk == NULL)
338                 return;
339
340         np = inet6_sk(sk);
341
342         if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
343                 goto out;
344
345         if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
346                 goto out;
347
348         if (np->recverr)
349                 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
350
351         sk->sk_err = err;
352         sk->sk_error_report(sk);
353 out:
354         sock_put(sk);
355 }
356
357 static inline int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
358 {
359         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
360                 kfree_skb(skb);
361                 return -1;
362         }
363
364         if (skb->ip_summed != CHECKSUM_UNNECESSARY) {
365                 if ((unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum))) {
366                         UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
367                         kfree_skb(skb);
368                         return 0;
369                 }
370                 skb->ip_summed = CHECKSUM_UNNECESSARY;
371         }
372
373         if (sock_queue_rcv_skb(sk,skb)<0) {
374                 UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
375                 kfree_skb(skb);
376                 return 0;
377         }
378         UDP6_INC_STATS_BH(UDP_MIB_INDATAGRAMS);
379         return 0;
380 }
381
382 static struct sock *udp_v6_mcast_next(struct sock *sk,
383                                       u16 loc_port, struct in6_addr *loc_addr,
384                                       u16 rmt_port, struct in6_addr *rmt_addr,
385                                       int dif)
386 {
387         struct hlist_node *node;
388         struct sock *s = sk;
389         unsigned short num = ntohs(loc_port);
390
391         sk_for_each_from(s, node) {
392                 struct inet_sock *inet = inet_sk(s);
393
394                 if (inet->num == num && s->sk_family == PF_INET6) {
395                         struct ipv6_pinfo *np = inet6_sk(s);
396                         if (inet->dport) {
397                                 if (inet->dport != rmt_port)
398                                         continue;
399                         }
400                         if (!ipv6_addr_any(&np->daddr) &&
401                             !ipv6_addr_equal(&np->daddr, rmt_addr))
402                                 continue;
403
404                         if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
405                                 continue;
406
407                         if (!ipv6_addr_any(&np->rcv_saddr)) {
408                                 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
409                                         continue;
410                         }
411                         if(!inet6_mc_check(s, loc_addr, rmt_addr))
412                                 continue;
413                         return s;
414                 }
415         }
416         return NULL;
417 }
418
419 /*
420  * Note: called only from the BH handler context,
421  * so we don't need to lock the hashes.
422  */
423 static void udpv6_mcast_deliver(struct udphdr *uh,
424                                 struct in6_addr *saddr, struct in6_addr *daddr,
425                                 struct sk_buff *skb)
426 {
427         struct sock *sk, *sk2;
428         int dif;
429
430         read_lock(&udp_hash_lock);
431         sk = sk_head(&udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]);
432         dif = skb->dev->ifindex;
433         sk = udp_v6_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif);
434         if (!sk) {
435                 kfree_skb(skb);
436                 goto out;
437         }
438
439         sk2 = sk;
440         while ((sk2 = udp_v6_mcast_next(sk_next(sk2), uh->dest, daddr,
441                                         uh->source, saddr, dif))) {
442                 struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC);
443                 if (buff)
444                         udpv6_queue_rcv_skb(sk2, buff);
445         }
446         udpv6_queue_rcv_skb(sk, skb);
447 out:
448         read_unlock(&udp_hash_lock);
449 }
450
451 static int udpv6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
452 {
453         struct sk_buff *skb = *pskb;
454         struct sock *sk;
455         struct udphdr *uh;
456         struct net_device *dev = skb->dev;
457         struct in6_addr *saddr, *daddr;
458         u32 ulen = 0;
459
460         if (!pskb_may_pull(skb, sizeof(struct udphdr)))
461                 goto short_packet;
462
463         saddr = &skb->nh.ipv6h->saddr;
464         daddr = &skb->nh.ipv6h->daddr;
465         uh = skb->h.uh;
466
467         ulen = ntohs(uh->len);
468
469         /* Check for jumbo payload */
470         if (ulen == 0)
471                 ulen = skb->len;
472
473         if (ulen > skb->len || ulen < sizeof(*uh))
474                 goto short_packet;
475
476         if (uh->check == 0) {
477                 /* RFC 2460 section 8.1 says that we SHOULD log
478                    this error. Well, it is reasonable.
479                  */
480                 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
481                 goto discard;
482         }
483
484         if (ulen < skb->len) {
485                 if (pskb_trim_rcsum(skb, ulen))
486                         goto discard;
487                 saddr = &skb->nh.ipv6h->saddr;
488                 daddr = &skb->nh.ipv6h->daddr;
489                 uh = skb->h.uh;
490         }
491
492         if (skb->ip_summed==CHECKSUM_HW) {
493                 skb->ip_summed = CHECKSUM_UNNECESSARY;
494                 if (csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, skb->csum)) {
495                         LIMIT_NETDEBUG(KERN_DEBUG "udp v6 hw csum failure.\n");
496                         skb->ip_summed = CHECKSUM_NONE;
497                 }
498         }
499         if (skb->ip_summed != CHECKSUM_UNNECESSARY)
500                 skb->csum = ~csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, 0);
501
502         /* 
503          *      Multicast receive code 
504          */
505         if (ipv6_addr_is_multicast(daddr)) {
506                 udpv6_mcast_deliver(uh, saddr, daddr, skb);
507                 return 0;
508         }
509
510         /* Unicast */
511
512         /* 
513          * check socket cache ... must talk to Alan about his plans
514          * for sock caches... i'll skip this for now.
515          */
516         sk = udp_v6_lookup(saddr, uh->source, daddr, uh->dest, dev->ifindex);
517
518         if (sk == NULL) {
519                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
520                         goto discard;
521
522                 if (skb->ip_summed != CHECKSUM_UNNECESSARY &&
523                     (unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)))
524                         goto discard;
525                 UDP6_INC_STATS_BH(UDP_MIB_NOPORTS);
526
527                 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0, dev);
528
529                 kfree_skb(skb);
530                 return(0);
531         }
532         
533         /* deliver */
534         
535         udpv6_queue_rcv_skb(sk, skb);
536         sock_put(sk);
537         return(0);
538
539 short_packet:   
540         if (net_ratelimit())
541                 printk(KERN_DEBUG "UDP: short packet: %d/%u\n", ulen, skb->len);
542
543 discard:
544         UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
545         kfree_skb(skb);
546         return(0);      
547 }
548 /*
549  * Throw away all pending data and cancel the corking. Socket is locked.
550  */
551 static void udp_v6_flush_pending_frames(struct sock *sk)
552 {
553         struct udp_sock *up = udp_sk(sk);
554
555         if (up->pending) {
556                 up->len = 0;
557                 up->pending = 0;
558                 ip6_flush_pending_frames(sk);
559         }
560 }
561
562 /*
563  *      Sending
564  */
565
566 static int udp_v6_push_pending_frames(struct sock *sk, struct udp_sock *up)
567 {
568         struct sk_buff *skb;
569         struct udphdr *uh;
570         struct inet_sock *inet = inet_sk(sk);
571         struct flowi *fl = &inet->cork.fl;
572         int err = 0;
573
574         /* Grab the skbuff where UDP header space exists. */
575         if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
576                 goto out;
577
578         /*
579          * Create a UDP header
580          */
581         uh = skb->h.uh;
582         uh->source = fl->fl_ip_sport;
583         uh->dest = fl->fl_ip_dport;
584         uh->len = htons(up->len);
585         uh->check = 0;
586
587         if (sk->sk_no_check == UDP_CSUM_NOXMIT) {
588                 skb->ip_summed = CHECKSUM_NONE;
589                 goto send;
590         }
591
592         if (skb_queue_len(&sk->sk_write_queue) == 1) {
593                 skb->csum = csum_partial((char *)uh,
594                                 sizeof(struct udphdr), skb->csum);
595                 uh->check = csum_ipv6_magic(&fl->fl6_src,
596                                             &fl->fl6_dst,
597                                             up->len, fl->proto, skb->csum);
598         } else {
599                 u32 tmp_csum = 0;
600
601                 skb_queue_walk(&sk->sk_write_queue, skb) {
602                         tmp_csum = csum_add(tmp_csum, skb->csum);
603                 }
604                 tmp_csum = csum_partial((char *)uh,
605                                 sizeof(struct udphdr), tmp_csum);
606                 tmp_csum = csum_ipv6_magic(&fl->fl6_src,
607                                            &fl->fl6_dst,
608                                            up->len, fl->proto, tmp_csum);
609                 uh->check = tmp_csum;
610
611         }
612         if (uh->check == 0)
613                 uh->check = -1;
614
615 send:
616         err = ip6_push_pending_frames(sk);
617 out:
618         up->len = 0;
619         up->pending = 0;
620         return err;
621 }
622
623 static int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk, 
624                   struct msghdr *msg, size_t len)
625 {
626         struct ipv6_txoptions opt_space;
627         struct udp_sock *up = udp_sk(sk);
628         struct inet_sock *inet = inet_sk(sk);
629         struct ipv6_pinfo *np = inet6_sk(sk);
630         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
631         struct in6_addr *daddr, *final_p = NULL, final;
632         struct ipv6_txoptions *opt = NULL;
633         struct ip6_flowlabel *flowlabel = NULL;
634         struct flowi *fl = &inet->cork.fl;
635         struct dst_entry *dst;
636         int addr_len = msg->msg_namelen;
637         int ulen = len;
638         int hlimit = -1;
639         int tclass = -1;
640         int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
641         int err;
642
643         /* destination address check */
644         if (sin6) {
645                 if (addr_len < offsetof(struct sockaddr, sa_data))
646                         return -EINVAL;
647
648                 switch (sin6->sin6_family) {
649                 case AF_INET6:
650                         if (addr_len < SIN6_LEN_RFC2133)
651                                 return -EINVAL;
652                         daddr = &sin6->sin6_addr;
653                         break;
654                 case AF_INET:
655                         goto do_udp_sendmsg;
656                 case AF_UNSPEC:
657                         msg->msg_name = sin6 = NULL;
658                         msg->msg_namelen = addr_len = 0;
659                         daddr = NULL;
660                         break;
661                 default:
662                         return -EINVAL;
663                 }
664         } else if (!up->pending) {
665                 if (sk->sk_state != TCP_ESTABLISHED)
666                         return -EDESTADDRREQ;
667                 daddr = &np->daddr;
668         } else 
669                 daddr = NULL;
670
671         if (daddr) {
672                 if (ipv6_addr_type(daddr) == IPV6_ADDR_MAPPED) {
673                         struct sockaddr_in sin;
674                         sin.sin_family = AF_INET;
675                         sin.sin_port = sin6 ? sin6->sin6_port : inet->dport;
676                         sin.sin_addr.s_addr = daddr->s6_addr32[3];
677                         msg->msg_name = &sin;
678                         msg->msg_namelen = sizeof(sin);
679 do_udp_sendmsg:
680                         if (__ipv6_only_sock(sk))
681                                 return -ENETUNREACH;
682                         return udp_sendmsg(iocb, sk, msg, len);
683                 }
684         }
685
686         if (up->pending == AF_INET)
687                 return udp_sendmsg(iocb, sk, msg, len);
688
689         /* Rough check on arithmetic overflow,
690            better check is made in ip6_build_xmit
691            */
692         if (len > INT_MAX - sizeof(struct udphdr))
693                 return -EMSGSIZE;
694         
695         if (up->pending) {
696                 /*
697                  * There are pending frames.
698                  * The socket lock must be held while it's corked.
699                  */
700                 lock_sock(sk);
701                 if (likely(up->pending)) {
702                         if (unlikely(up->pending != AF_INET6)) {
703                                 release_sock(sk);
704                                 return -EAFNOSUPPORT;
705                         }
706                         dst = NULL;
707                         goto do_append_data;
708                 }
709                 release_sock(sk);
710         }
711         ulen += sizeof(struct udphdr);
712
713         memset(fl, 0, sizeof(*fl));
714
715         if (sin6) {
716                 if (sin6->sin6_port == 0)
717                         return -EINVAL;
718
719                 fl->fl_ip_dport = sin6->sin6_port;
720                 daddr = &sin6->sin6_addr;
721
722                 if (np->sndflow) {
723                         fl->fl6_flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
724                         if (fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
725                                 flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
726                                 if (flowlabel == NULL)
727                                         return -EINVAL;
728                                 daddr = &flowlabel->dst;
729                         }
730                 }
731
732                 /*
733                  * Otherwise it will be difficult to maintain
734                  * sk->sk_dst_cache.
735                  */
736                 if (sk->sk_state == TCP_ESTABLISHED &&
737                     ipv6_addr_equal(daddr, &np->daddr))
738                         daddr = &np->daddr;
739
740                 if (addr_len >= sizeof(struct sockaddr_in6) &&
741                     sin6->sin6_scope_id &&
742                     ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
743                         fl->oif = sin6->sin6_scope_id;
744         } else {
745                 if (sk->sk_state != TCP_ESTABLISHED)
746                         return -EDESTADDRREQ;
747
748                 fl->fl_ip_dport = inet->dport;
749                 daddr = &np->daddr;
750                 fl->fl6_flowlabel = np->flow_label;
751         }
752
753         if (!fl->oif)
754                 fl->oif = sk->sk_bound_dev_if;
755
756         if (msg->msg_controllen) {
757                 opt = &opt_space;
758                 memset(opt, 0, sizeof(struct ipv6_txoptions));
759                 opt->tot_len = sizeof(*opt);
760
761                 err = datagram_send_ctl(msg, fl, opt, &hlimit, &tclass);
762                 if (err < 0) {
763                         fl6_sock_release(flowlabel);
764                         return err;
765                 }
766                 if ((fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
767                         flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
768                         if (flowlabel == NULL)
769                                 return -EINVAL;
770                 }
771                 if (!(opt->opt_nflen|opt->opt_flen))
772                         opt = NULL;
773         }
774         if (opt == NULL)
775                 opt = np->opt;
776         opt = fl6_merge_options(&opt_space, flowlabel, opt);
777
778         fl->proto = IPPROTO_UDP;
779         ipv6_addr_copy(&fl->fl6_dst, daddr);
780         if (ipv6_addr_any(&fl->fl6_src) && !ipv6_addr_any(&np->saddr))
781                 ipv6_addr_copy(&fl->fl6_src, &np->saddr);
782         fl->fl_ip_sport = inet->sport;
783         
784         /* merge ip6_build_xmit from ip6_output */
785         if (opt && opt->srcrt) {
786                 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
787                 ipv6_addr_copy(&final, &fl->fl6_dst);
788                 ipv6_addr_copy(&fl->fl6_dst, rt0->addr);
789                 final_p = &final;
790         }
791
792         if (!fl->oif && ipv6_addr_is_multicast(&fl->fl6_dst))
793                 fl->oif = np->mcast_oif;
794
795         err = ip6_dst_lookup(sk, &dst, fl);
796         if (err)
797                 goto out;
798         if (final_p)
799                 ipv6_addr_copy(&fl->fl6_dst, final_p);
800
801         if ((err = xfrm_lookup(&dst, fl, sk, 0)) < 0)
802                 goto out;
803
804         if (hlimit < 0) {
805                 if (ipv6_addr_is_multicast(&fl->fl6_dst))
806                         hlimit = np->mcast_hops;
807                 else
808                         hlimit = np->hop_limit;
809                 if (hlimit < 0)
810                         hlimit = dst_metric(dst, RTAX_HOPLIMIT);
811                 if (hlimit < 0)
812                         hlimit = ipv6_get_hoplimit(dst->dev);
813         }
814
815         if (tclass < 0) {
816                 tclass = np->tclass;
817                 if (tclass < 0)
818                         tclass = 0;
819         }
820
821         if (msg->msg_flags&MSG_CONFIRM)
822                 goto do_confirm;
823 back_from_confirm:
824
825         lock_sock(sk);
826         if (unlikely(up->pending)) {
827                 /* The socket is already corked while preparing it. */
828                 /* ... which is an evident application bug. --ANK */
829                 release_sock(sk);
830
831                 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
832                 err = -EINVAL;
833                 goto out;
834         }
835
836         up->pending = AF_INET6;
837
838 do_append_data:
839         up->len += ulen;
840         err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov, ulen,
841                 sizeof(struct udphdr), hlimit, tclass, opt, fl,
842                 (struct rt6_info*)dst,
843                 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
844         if (err)
845                 udp_v6_flush_pending_frames(sk);
846         else if (!corkreq)
847                 err = udp_v6_push_pending_frames(sk, up);
848
849         if (dst)
850                 ip6_dst_store(sk, dst,
851                               ipv6_addr_equal(&fl->fl6_dst, &np->daddr) ?
852                               &np->daddr : NULL);
853         if (err > 0)
854                 err = np->recverr ? net_xmit_errno(err) : 0;
855         release_sock(sk);
856 out:
857         fl6_sock_release(flowlabel);
858         if (!err) {
859                 UDP6_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS);
860                 return len;
861         }
862         return err;
863
864 do_confirm:
865         dst_confirm(dst);
866         if (!(msg->msg_flags&MSG_PROBE) || len)
867                 goto back_from_confirm;
868         err = 0;
869         goto out;
870 }
871
872 static int udpv6_destroy_sock(struct sock *sk)
873 {
874         lock_sock(sk);
875         udp_v6_flush_pending_frames(sk);
876         release_sock(sk);
877
878         inet6_destroy_sock(sk);
879
880         return 0;
881 }
882
883 /*
884  *      Socket option code for UDP
885  */
886 static int udpv6_setsockopt(struct sock *sk, int level, int optname, 
887                           char __user *optval, int optlen)
888 {
889         struct udp_sock *up = udp_sk(sk);
890         int val;
891         int err = 0;
892
893         if (level != SOL_UDP)
894                 return ipv6_setsockopt(sk, level, optname, optval, optlen);
895
896         if(optlen<sizeof(int))
897                 return -EINVAL;
898
899         if (get_user(val, (int __user *)optval))
900                 return -EFAULT;
901
902         switch(optname) {
903         case UDP_CORK:
904                 if (val != 0) {
905                         up->corkflag = 1;
906                 } else {
907                         up->corkflag = 0;
908                         lock_sock(sk);
909                         udp_v6_push_pending_frames(sk, up);
910                         release_sock(sk);
911                 }
912                 break;
913                 
914         case UDP_ENCAP:
915                 switch (val) {
916                 case 0:
917                         up->encap_type = val;
918                         break;
919                 default:
920                         err = -ENOPROTOOPT;
921                         break;
922                 }
923                 break;
924
925         default:
926                 err = -ENOPROTOOPT;
927                 break;
928         };
929
930         return err;
931 }
932
933 static int udpv6_getsockopt(struct sock *sk, int level, int optname, 
934                           char __user *optval, int __user *optlen)
935 {
936         struct udp_sock *up = udp_sk(sk);
937         int val, len;
938
939         if (level != SOL_UDP)
940                 return ipv6_getsockopt(sk, level, optname, optval, optlen);
941
942         if(get_user(len,optlen))
943                 return -EFAULT;
944
945         len = min_t(unsigned int, len, sizeof(int));
946         
947         if(len < 0)
948                 return -EINVAL;
949
950         switch(optname) {
951         case UDP_CORK:
952                 val = up->corkflag;
953                 break;
954
955         case UDP_ENCAP:
956                 val = up->encap_type;
957                 break;
958
959         default:
960                 return -ENOPROTOOPT;
961         };
962
963         if(put_user(len, optlen))
964                 return -EFAULT;
965         if(copy_to_user(optval, &val,len))
966                 return -EFAULT;
967         return 0;
968 }
969
970 static struct inet6_protocol udpv6_protocol = {
971         .handler        =       udpv6_rcv,
972         .err_handler    =       udpv6_err,
973         .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
974 };
975
976 /* ------------------------------------------------------------------------ */
977 #ifdef CONFIG_PROC_FS
978
979 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
980 {
981         struct inet_sock *inet = inet_sk(sp);
982         struct ipv6_pinfo *np = inet6_sk(sp);
983         struct in6_addr *dest, *src;
984         __u16 destp, srcp;
985
986         dest  = &np->daddr;
987         src   = &np->rcv_saddr;
988         destp = ntohs(inet->dport);
989         srcp  = ntohs(inet->sport);
990         seq_printf(seq,
991                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
992                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p\n",
993                    bucket,
994                    src->s6_addr32[0], src->s6_addr32[1],
995                    src->s6_addr32[2], src->s6_addr32[3], srcp,
996                    dest->s6_addr32[0], dest->s6_addr32[1],
997                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
998                    sp->sk_state, 
999                    atomic_read(&sp->sk_wmem_alloc),
1000                    atomic_read(&sp->sk_rmem_alloc),
1001                    0, 0L, 0,
1002                    sock_i_uid(sp), 0,
1003                    sock_i_ino(sp),
1004                    atomic_read(&sp->sk_refcnt), sp);
1005 }
1006
1007 static int udp6_seq_show(struct seq_file *seq, void *v)
1008 {
1009         if (v == SEQ_START_TOKEN)
1010                 seq_printf(seq,
1011                            "  sl  "
1012                            "local_address                         "
1013                            "remote_address                        "
1014                            "st tx_queue rx_queue tr tm->when retrnsmt"
1015                            "   uid  timeout inode\n");
1016         else
1017                 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1018         return 0;
1019 }
1020
1021 static struct file_operations udp6_seq_fops;
1022 static struct udp_seq_afinfo udp6_seq_afinfo = {
1023         .owner          = THIS_MODULE,
1024         .name           = "udp6",
1025         .family         = AF_INET6,
1026         .seq_show       = udp6_seq_show,
1027         .seq_fops       = &udp6_seq_fops,
1028 };
1029
1030 int __init udp6_proc_init(void)
1031 {
1032         return udp_proc_register(&udp6_seq_afinfo);
1033 }
1034
1035 void udp6_proc_exit(void) {
1036         udp_proc_unregister(&udp6_seq_afinfo);
1037 }
1038 #endif /* CONFIG_PROC_FS */
1039
1040 /* ------------------------------------------------------------------------ */
1041
1042 struct proto udpv6_prot = {
1043         .name =         "UDPv6",
1044         .owner =        THIS_MODULE,
1045         .close =        udpv6_close,
1046         .connect =      ip6_datagram_connect,
1047         .disconnect =   udp_disconnect,
1048         .ioctl =        udp_ioctl,
1049         .destroy =      udpv6_destroy_sock,
1050         .setsockopt =   udpv6_setsockopt,
1051         .getsockopt =   udpv6_getsockopt,
1052         .sendmsg =      udpv6_sendmsg,
1053         .recvmsg =      udpv6_recvmsg,
1054         .backlog_rcv =  udpv6_queue_rcv_skb,
1055         .hash =         udp_v6_hash,
1056         .unhash =       udp_v6_unhash,
1057         .get_port =     udp_v6_get_port,
1058         .obj_size =     sizeof(struct udp6_sock),
1059 };
1060
1061 static struct inet_protosw udpv6_protosw = {
1062         .type =      SOCK_DGRAM,
1063         .protocol =  IPPROTO_UDP,
1064         .prot =      &udpv6_prot,
1065         .ops =       &inet6_dgram_ops,
1066         .capability =-1,
1067         .no_check =  UDP_CSUM_DEFAULT,
1068         .flags =     INET_PROTOSW_PERMANENT,
1069 };
1070
1071
1072 void __init udpv6_init(void)
1073 {
1074         if (inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP) < 0)
1075                 printk(KERN_ERR "udpv6_init: Could not register protocol\n");
1076         inet6_register_protosw(&udpv6_protosw);
1077 }