xref: /linux/net/ipv6/udp.c (revision 6e8331ac6973435b1e7604c30f2ad394035b46e1)
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 	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
349 		kfree_skb(skb);
350 		return -1;
351 	}
352 
353 	if (skb_checksum_complete(skb)) {
354 		UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
355 		kfree_skb(skb);
356 		return 0;
357 	}
358 
359 	if (sock_queue_rcv_skb(sk,skb)<0) {
360 		UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
361 		kfree_skb(skb);
362 		return 0;
363 	}
364 	UDP6_INC_STATS_BH(UDP_MIB_INDATAGRAMS);
365 	return 0;
366 }
367 
368 static struct sock *udp_v6_mcast_next(struct sock *sk,
369 				      u16 loc_port, struct in6_addr *loc_addr,
370 				      u16 rmt_port, struct in6_addr *rmt_addr,
371 				      int dif)
372 {
373 	struct hlist_node *node;
374 	struct sock *s = sk;
375 	unsigned short num = ntohs(loc_port);
376 
377 	sk_for_each_from(s, node) {
378 		struct inet_sock *inet = inet_sk(s);
379 
380 		if (inet->num == num && s->sk_family == PF_INET6) {
381 			struct ipv6_pinfo *np = inet6_sk(s);
382 			if (inet->dport) {
383 				if (inet->dport != rmt_port)
384 					continue;
385 			}
386 			if (!ipv6_addr_any(&np->daddr) &&
387 			    !ipv6_addr_equal(&np->daddr, rmt_addr))
388 				continue;
389 
390 			if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
391 				continue;
392 
393 			if (!ipv6_addr_any(&np->rcv_saddr)) {
394 				if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
395 					continue;
396 			}
397 			if(!inet6_mc_check(s, loc_addr, rmt_addr))
398 				continue;
399 			return s;
400 		}
401 	}
402 	return NULL;
403 }
404 
405 /*
406  * Note: called only from the BH handler context,
407  * so we don't need to lock the hashes.
408  */
409 static void udpv6_mcast_deliver(struct udphdr *uh,
410 				struct in6_addr *saddr, struct in6_addr *daddr,
411 				struct sk_buff *skb)
412 {
413 	struct sock *sk, *sk2;
414 	int dif;
415 
416 	read_lock(&udp_hash_lock);
417 	sk = sk_head(&udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]);
418 	dif = skb->dev->ifindex;
419 	sk = udp_v6_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif);
420 	if (!sk) {
421 		kfree_skb(skb);
422 		goto out;
423 	}
424 
425 	sk2 = sk;
426 	while ((sk2 = udp_v6_mcast_next(sk_next(sk2), uh->dest, daddr,
427 					uh->source, saddr, dif))) {
428 		struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC);
429 		if (buff)
430 			udpv6_queue_rcv_skb(sk2, buff);
431 	}
432 	udpv6_queue_rcv_skb(sk, skb);
433 out:
434 	read_unlock(&udp_hash_lock);
435 }
436 
437 static int udpv6_rcv(struct sk_buff **pskb)
438 {
439 	struct sk_buff *skb = *pskb;
440 	struct sock *sk;
441   	struct udphdr *uh;
442 	struct net_device *dev = skb->dev;
443 	struct in6_addr *saddr, *daddr;
444 	u32 ulen = 0;
445 
446 	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
447 		goto short_packet;
448 
449 	saddr = &skb->nh.ipv6h->saddr;
450 	daddr = &skb->nh.ipv6h->daddr;
451 	uh = skb->h.uh;
452 
453 	ulen = ntohs(uh->len);
454 
455 	/* Check for jumbo payload */
456 	if (ulen == 0)
457 		ulen = skb->len;
458 
459 	if (ulen > skb->len || ulen < sizeof(*uh))
460 		goto short_packet;
461 
462 	if (uh->check == 0) {
463 		/* RFC 2460 section 8.1 says that we SHOULD log
464 		   this error. Well, it is reasonable.
465 		 */
466 		LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
467 		goto discard;
468 	}
469 
470 	if (ulen < skb->len) {
471 		if (pskb_trim_rcsum(skb, ulen))
472 			goto discard;
473 		saddr = &skb->nh.ipv6h->saddr;
474 		daddr = &skb->nh.ipv6h->daddr;
475 		uh = skb->h.uh;
476 	}
477 
478 	if (skb->ip_summed == CHECKSUM_HW &&
479 	    !csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, skb->csum))
480 		skb->ip_summed = CHECKSUM_UNNECESSARY;
481 
482 	if (skb->ip_summed != CHECKSUM_UNNECESSARY)
483 		skb->csum = ~csum_ipv6_magic(saddr, daddr, ulen, IPPROTO_UDP, 0);
484 
485 	/*
486 	 *	Multicast receive code
487 	 */
488 	if (ipv6_addr_is_multicast(daddr)) {
489 		udpv6_mcast_deliver(uh, saddr, daddr, skb);
490 		return 0;
491 	}
492 
493 	/* Unicast */
494 
495 	/*
496 	 * check socket cache ... must talk to Alan about his plans
497 	 * for sock caches... i'll skip this for now.
498 	 */
499 	sk = udp_v6_lookup(saddr, uh->source, daddr, uh->dest, dev->ifindex);
500 
501 	if (sk == NULL) {
502 		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
503 			goto discard;
504 
505 		if (skb_checksum_complete(skb))
506 			goto discard;
507 		UDP6_INC_STATS_BH(UDP_MIB_NOPORTS);
508 
509 		icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0, dev);
510 
511 		kfree_skb(skb);
512 		return(0);
513 	}
514 
515 	/* deliver */
516 
517 	udpv6_queue_rcv_skb(sk, skb);
518 	sock_put(sk);
519 	return(0);
520 
521 short_packet:
522 	if (net_ratelimit())
523 		printk(KERN_DEBUG "UDP: short packet: %d/%u\n", ulen, skb->len);
524 
525 discard:
526 	UDP6_INC_STATS_BH(UDP_MIB_INERRORS);
527 	kfree_skb(skb);
528 	return(0);
529 }
530 /*
531  * Throw away all pending data and cancel the corking. Socket is locked.
532  */
533 static void udp_v6_flush_pending_frames(struct sock *sk)
534 {
535 	struct udp_sock *up = udp_sk(sk);
536 
537 	if (up->pending) {
538 		up->len = 0;
539 		up->pending = 0;
540 		ip6_flush_pending_frames(sk);
541         }
542 }
543 
544 /*
545  *	Sending
546  */
547 
548 static int udp_v6_push_pending_frames(struct sock *sk, struct udp_sock *up)
549 {
550 	struct sk_buff *skb;
551 	struct udphdr *uh;
552 	struct inet_sock *inet = inet_sk(sk);
553 	struct flowi *fl = &inet->cork.fl;
554 	int err = 0;
555 
556 	/* Grab the skbuff where UDP header space exists. */
557 	if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
558 		goto out;
559 
560 	/*
561 	 * Create a UDP header
562 	 */
563 	uh = skb->h.uh;
564 	uh->source = fl->fl_ip_sport;
565 	uh->dest = fl->fl_ip_dport;
566 	uh->len = htons(up->len);
567 	uh->check = 0;
568 
569 	if (sk->sk_no_check == UDP_CSUM_NOXMIT) {
570 		skb->ip_summed = CHECKSUM_NONE;
571 		goto send;
572 	}
573 
574 	if (skb_queue_len(&sk->sk_write_queue) == 1) {
575 		skb->csum = csum_partial((char *)uh,
576 				sizeof(struct udphdr), skb->csum);
577 		uh->check = csum_ipv6_magic(&fl->fl6_src,
578 					    &fl->fl6_dst,
579 					    up->len, fl->proto, skb->csum);
580 	} else {
581 		u32 tmp_csum = 0;
582 
583 		skb_queue_walk(&sk->sk_write_queue, skb) {
584 			tmp_csum = csum_add(tmp_csum, skb->csum);
585 		}
586 		tmp_csum = csum_partial((char *)uh,
587 				sizeof(struct udphdr), tmp_csum);
588                 tmp_csum = csum_ipv6_magic(&fl->fl6_src,
589 					   &fl->fl6_dst,
590 					   up->len, fl->proto, tmp_csum);
591                 uh->check = tmp_csum;
592 
593 	}
594 	if (uh->check == 0)
595 		uh->check = -1;
596 
597 send:
598 	err = ip6_push_pending_frames(sk);
599 out:
600 	up->len = 0;
601 	up->pending = 0;
602 	return err;
603 }
604 
605 static int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
606 		  struct msghdr *msg, size_t len)
607 {
608 	struct ipv6_txoptions opt_space;
609 	struct udp_sock *up = udp_sk(sk);
610 	struct inet_sock *inet = inet_sk(sk);
611 	struct ipv6_pinfo *np = inet6_sk(sk);
612 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
613 	struct in6_addr *daddr, *final_p = NULL, final;
614 	struct ipv6_txoptions *opt = NULL;
615 	struct ip6_flowlabel *flowlabel = NULL;
616 	struct flowi *fl = &inet->cork.fl;
617 	struct dst_entry *dst;
618 	int addr_len = msg->msg_namelen;
619 	int ulen = len;
620 	int hlimit = -1;
621 	int tclass = -1;
622 	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
623 	int err;
624 	int connected = 0;
625 
626 	/* destination address check */
627 	if (sin6) {
628 		if (addr_len < offsetof(struct sockaddr, sa_data))
629 			return -EINVAL;
630 
631 		switch (sin6->sin6_family) {
632 		case AF_INET6:
633 			if (addr_len < SIN6_LEN_RFC2133)
634 				return -EINVAL;
635 			daddr = &sin6->sin6_addr;
636 			break;
637 		case AF_INET:
638 			goto do_udp_sendmsg;
639 		case AF_UNSPEC:
640 			msg->msg_name = sin6 = NULL;
641 			msg->msg_namelen = addr_len = 0;
642 			daddr = NULL;
643 			break;
644 		default:
645 			return -EINVAL;
646 		}
647 	} else if (!up->pending) {
648 		if (sk->sk_state != TCP_ESTABLISHED)
649 			return -EDESTADDRREQ;
650 		daddr = &np->daddr;
651 	} else
652 		daddr = NULL;
653 
654 	if (daddr) {
655 		if (ipv6_addr_type(daddr) == IPV6_ADDR_MAPPED) {
656 			struct sockaddr_in sin;
657 			sin.sin_family = AF_INET;
658 			sin.sin_port = sin6 ? sin6->sin6_port : inet->dport;
659 			sin.sin_addr.s_addr = daddr->s6_addr32[3];
660 			msg->msg_name = &sin;
661 			msg->msg_namelen = sizeof(sin);
662 do_udp_sendmsg:
663 			if (__ipv6_only_sock(sk))
664 				return -ENETUNREACH;
665 			return udp_sendmsg(iocb, sk, msg, len);
666 		}
667 	}
668 
669 	if (up->pending == AF_INET)
670 		return udp_sendmsg(iocb, sk, msg, len);
671 
672 	/* Rough check on arithmetic overflow,
673 	   better check is made in ip6_build_xmit
674 	   */
675 	if (len > INT_MAX - sizeof(struct udphdr))
676 		return -EMSGSIZE;
677 
678 	if (up->pending) {
679 		/*
680 		 * There are pending frames.
681 		 * The socket lock must be held while it's corked.
682 		 */
683 		lock_sock(sk);
684 		if (likely(up->pending)) {
685 			if (unlikely(up->pending != AF_INET6)) {
686 				release_sock(sk);
687 				return -EAFNOSUPPORT;
688 			}
689 			dst = NULL;
690 			goto do_append_data;
691 		}
692 		release_sock(sk);
693 	}
694 	ulen += sizeof(struct udphdr);
695 
696 	memset(fl, 0, sizeof(*fl));
697 
698 	if (sin6) {
699 		if (sin6->sin6_port == 0)
700 			return -EINVAL;
701 
702 		fl->fl_ip_dport = sin6->sin6_port;
703 		daddr = &sin6->sin6_addr;
704 
705 		if (np->sndflow) {
706 			fl->fl6_flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
707 			if (fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
708 				flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
709 				if (flowlabel == NULL)
710 					return -EINVAL;
711 				daddr = &flowlabel->dst;
712 			}
713 		}
714 
715 		/*
716 		 * Otherwise it will be difficult to maintain
717 		 * sk->sk_dst_cache.
718 		 */
719 		if (sk->sk_state == TCP_ESTABLISHED &&
720 		    ipv6_addr_equal(daddr, &np->daddr))
721 			daddr = &np->daddr;
722 
723 		if (addr_len >= sizeof(struct sockaddr_in6) &&
724 		    sin6->sin6_scope_id &&
725 		    ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
726 			fl->oif = sin6->sin6_scope_id;
727 	} else {
728 		if (sk->sk_state != TCP_ESTABLISHED)
729 			return -EDESTADDRREQ;
730 
731 		fl->fl_ip_dport = inet->dport;
732 		daddr = &np->daddr;
733 		fl->fl6_flowlabel = np->flow_label;
734 		connected = 1;
735 	}
736 
737 	if (!fl->oif)
738 		fl->oif = sk->sk_bound_dev_if;
739 
740 	if (msg->msg_controllen) {
741 		opt = &opt_space;
742 		memset(opt, 0, sizeof(struct ipv6_txoptions));
743 		opt->tot_len = sizeof(*opt);
744 
745 		err = datagram_send_ctl(msg, fl, opt, &hlimit, &tclass);
746 		if (err < 0) {
747 			fl6_sock_release(flowlabel);
748 			return err;
749 		}
750 		if ((fl->fl6_flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
751 			flowlabel = fl6_sock_lookup(sk, fl->fl6_flowlabel);
752 			if (flowlabel == NULL)
753 				return -EINVAL;
754 		}
755 		if (!(opt->opt_nflen|opt->opt_flen))
756 			opt = NULL;
757 		connected = 0;
758 	}
759 	if (opt == NULL)
760 		opt = np->opt;
761 	if (flowlabel)
762 		opt = fl6_merge_options(&opt_space, flowlabel, opt);
763 	opt = ipv6_fixup_options(&opt_space, opt);
764 
765 	fl->proto = IPPROTO_UDP;
766 	ipv6_addr_copy(&fl->fl6_dst, daddr);
767 	if (ipv6_addr_any(&fl->fl6_src) && !ipv6_addr_any(&np->saddr))
768 		ipv6_addr_copy(&fl->fl6_src, &np->saddr);
769 	fl->fl_ip_sport = inet->sport;
770 
771 	/* merge ip6_build_xmit from ip6_output */
772 	if (opt && opt->srcrt) {
773 		struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
774 		ipv6_addr_copy(&final, &fl->fl6_dst);
775 		ipv6_addr_copy(&fl->fl6_dst, rt0->addr);
776 		final_p = &final;
777 		connected = 0;
778 	}
779 
780 	if (!fl->oif && ipv6_addr_is_multicast(&fl->fl6_dst)) {
781 		fl->oif = np->mcast_oif;
782 		connected = 0;
783 	}
784 
785 	err = ip6_sk_dst_lookup(sk, &dst, fl);
786 	if (err)
787 		goto out;
788 	if (final_p)
789 		ipv6_addr_copy(&fl->fl6_dst, final_p);
790 
791 	if ((err = xfrm_lookup(&dst, fl, sk, 0)) < 0)
792 		goto out;
793 
794 	if (hlimit < 0) {
795 		if (ipv6_addr_is_multicast(&fl->fl6_dst))
796 			hlimit = np->mcast_hops;
797 		else
798 			hlimit = np->hop_limit;
799 		if (hlimit < 0)
800 			hlimit = dst_metric(dst, RTAX_HOPLIMIT);
801 		if (hlimit < 0)
802 			hlimit = ipv6_get_hoplimit(dst->dev);
803 	}
804 
805 	if (tclass < 0) {
806 		tclass = np->tclass;
807 		if (tclass < 0)
808 			tclass = 0;
809 	}
810 
811 	if (msg->msg_flags&MSG_CONFIRM)
812 		goto do_confirm;
813 back_from_confirm:
814 
815 	lock_sock(sk);
816 	if (unlikely(up->pending)) {
817 		/* The socket is already corked while preparing it. */
818 		/* ... which is an evident application bug. --ANK */
819 		release_sock(sk);
820 
821 		LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
822 		err = -EINVAL;
823 		goto out;
824 	}
825 
826 	up->pending = AF_INET6;
827 
828 do_append_data:
829 	up->len += ulen;
830 	err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov, ulen,
831 		sizeof(struct udphdr), hlimit, tclass, opt, fl,
832 		(struct rt6_info*)dst,
833 		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
834 	if (err)
835 		udp_v6_flush_pending_frames(sk);
836 	else if (!corkreq)
837 		err = udp_v6_push_pending_frames(sk, up);
838 
839 	if (dst) {
840 		if (connected) {
841 			ip6_dst_store(sk, dst,
842 				      ipv6_addr_equal(&fl->fl6_dst, &np->daddr) ?
843 				      &np->daddr : NULL);
844 		} else {
845 			dst_release(dst);
846 		}
847 	}
848 
849 	if (err > 0)
850 		err = np->recverr ? net_xmit_errno(err) : 0;
851 	release_sock(sk);
852 out:
853 	fl6_sock_release(flowlabel);
854 	if (!err) {
855 		UDP6_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS);
856 		return len;
857 	}
858 	return err;
859 
860 do_confirm:
861 	dst_confirm(dst);
862 	if (!(msg->msg_flags&MSG_PROBE) || len)
863 		goto back_from_confirm;
864 	err = 0;
865 	goto out;
866 }
867 
868 static int udpv6_destroy_sock(struct sock *sk)
869 {
870 	lock_sock(sk);
871 	udp_v6_flush_pending_frames(sk);
872 	release_sock(sk);
873 
874 	inet6_destroy_sock(sk);
875 
876 	return 0;
877 }
878 
879 /*
880  *	Socket option code for UDP
881  */
882 static int do_udpv6_setsockopt(struct sock *sk, int level, int optname,
883 			  char __user *optval, int optlen)
884 {
885 	struct udp_sock *up = udp_sk(sk);
886 	int val;
887 	int err = 0;
888 
889 	if(optlen<sizeof(int))
890 		return -EINVAL;
891 
892 	if (get_user(val, (int __user *)optval))
893 		return -EFAULT;
894 
895 	switch(optname) {
896 	case UDP_CORK:
897 		if (val != 0) {
898 			up->corkflag = 1;
899 		} else {
900 			up->corkflag = 0;
901 			lock_sock(sk);
902 			udp_v6_push_pending_frames(sk, up);
903 			release_sock(sk);
904 		}
905 		break;
906 
907 	case UDP_ENCAP:
908 		switch (val) {
909 		case 0:
910 			up->encap_type = val;
911 			break;
912 		default:
913 			err = -ENOPROTOOPT;
914 			break;
915 		}
916 		break;
917 
918 	default:
919 		err = -ENOPROTOOPT;
920 		break;
921 	};
922 
923 	return err;
924 }
925 
926 static int udpv6_setsockopt(struct sock *sk, int level, int optname,
927 			  char __user *optval, int optlen)
928 {
929 	if (level != SOL_UDP)
930 		return ipv6_setsockopt(sk, level, optname, optval, optlen);
931 	return do_udpv6_setsockopt(sk, level, optname, optval, optlen);
932 }
933 
934 #ifdef CONFIG_COMPAT
935 static int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
936 				   char __user *optval, int optlen)
937 {
938 	if (level != SOL_UDP)
939 		return compat_ipv6_setsockopt(sk, level, optname,
940 					      optval, optlen);
941 	return do_udpv6_setsockopt(sk, level, optname, optval, optlen);
942 }
943 #endif
944 
945 static int do_udpv6_getsockopt(struct sock *sk, int level, int optname,
946 			  char __user *optval, int __user *optlen)
947 {
948 	struct udp_sock *up = udp_sk(sk);
949 	int val, len;
950 
951 	if(get_user(len,optlen))
952 		return -EFAULT;
953 
954 	len = min_t(unsigned int, len, sizeof(int));
955 
956 	if(len < 0)
957 		return -EINVAL;
958 
959 	switch(optname) {
960 	case UDP_CORK:
961 		val = up->corkflag;
962 		break;
963 
964 	case UDP_ENCAP:
965 		val = up->encap_type;
966 		break;
967 
968 	default:
969 		return -ENOPROTOOPT;
970 	};
971 
972   	if(put_user(len, optlen))
973   		return -EFAULT;
974 	if(copy_to_user(optval, &val,len))
975 		return -EFAULT;
976   	return 0;
977 }
978 
979 static int udpv6_getsockopt(struct sock *sk, int level, int optname,
980 			  char __user *optval, int __user *optlen)
981 {
982 	if (level != SOL_UDP)
983 		return ipv6_getsockopt(sk, level, optname, optval, optlen);
984 	return do_udpv6_getsockopt(sk, level, optname, optval, optlen);
985 }
986 
987 #ifdef CONFIG_COMPAT
988 static int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
989 				   char __user *optval, int __user *optlen)
990 {
991 	if (level != SOL_UDP)
992 		return compat_ipv6_getsockopt(sk, level, optname,
993 					      optval, optlen);
994 	return do_udpv6_getsockopt(sk, level, optname, optval, optlen);
995 }
996 #endif
997 
998 static struct inet6_protocol udpv6_protocol = {
999 	.handler	=	udpv6_rcv,
1000 	.err_handler	=	udpv6_err,
1001 	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1002 };
1003 
1004 /* ------------------------------------------------------------------------ */
1005 #ifdef CONFIG_PROC_FS
1006 
1007 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1008 {
1009 	struct inet_sock *inet = inet_sk(sp);
1010 	struct ipv6_pinfo *np = inet6_sk(sp);
1011 	struct in6_addr *dest, *src;
1012 	__u16 destp, srcp;
1013 
1014 	dest  = &np->daddr;
1015 	src   = &np->rcv_saddr;
1016 	destp = ntohs(inet->dport);
1017 	srcp  = ntohs(inet->sport);
1018 	seq_printf(seq,
1019 		   "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1020 		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p\n",
1021 		   bucket,
1022 		   src->s6_addr32[0], src->s6_addr32[1],
1023 		   src->s6_addr32[2], src->s6_addr32[3], srcp,
1024 		   dest->s6_addr32[0], dest->s6_addr32[1],
1025 		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
1026 		   sp->sk_state,
1027 		   atomic_read(&sp->sk_wmem_alloc),
1028 		   atomic_read(&sp->sk_rmem_alloc),
1029 		   0, 0L, 0,
1030 		   sock_i_uid(sp), 0,
1031 		   sock_i_ino(sp),
1032 		   atomic_read(&sp->sk_refcnt), sp);
1033 }
1034 
1035 static int udp6_seq_show(struct seq_file *seq, void *v)
1036 {
1037 	if (v == SEQ_START_TOKEN)
1038 		seq_printf(seq,
1039 			   "  sl  "
1040 			   "local_address                         "
1041 			   "remote_address                        "
1042 			   "st tx_queue rx_queue tr tm->when retrnsmt"
1043 			   "   uid  timeout inode\n");
1044 	else
1045 		udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1046 	return 0;
1047 }
1048 
1049 static struct file_operations udp6_seq_fops;
1050 static struct udp_seq_afinfo udp6_seq_afinfo = {
1051 	.owner		= THIS_MODULE,
1052 	.name		= "udp6",
1053 	.family		= AF_INET6,
1054 	.seq_show	= udp6_seq_show,
1055 	.seq_fops	= &udp6_seq_fops,
1056 };
1057 
1058 int __init udp6_proc_init(void)
1059 {
1060 	return udp_proc_register(&udp6_seq_afinfo);
1061 }
1062 
1063 void udp6_proc_exit(void) {
1064 	udp_proc_unregister(&udp6_seq_afinfo);
1065 }
1066 #endif /* CONFIG_PROC_FS */
1067 
1068 /* ------------------------------------------------------------------------ */
1069 
1070 struct proto udpv6_prot = {
1071 	.name		   = "UDPv6",
1072 	.owner		   = THIS_MODULE,
1073 	.close		   = udpv6_close,
1074 	.connect	   = ip6_datagram_connect,
1075 	.disconnect	   = udp_disconnect,
1076 	.ioctl		   = udp_ioctl,
1077 	.destroy	   = udpv6_destroy_sock,
1078 	.setsockopt	   = udpv6_setsockopt,
1079 	.getsockopt	   = udpv6_getsockopt,
1080 	.sendmsg	   = udpv6_sendmsg,
1081 	.recvmsg	   = udpv6_recvmsg,
1082 	.backlog_rcv	   = udpv6_queue_rcv_skb,
1083 	.hash		   = udp_v6_hash,
1084 	.unhash		   = udp_v6_unhash,
1085 	.get_port	   = udp_v6_get_port,
1086 	.obj_size	   = sizeof(struct udp6_sock),
1087 #ifdef CONFIG_COMPAT
1088 	.compat_setsockopt = compat_udpv6_setsockopt,
1089 	.compat_getsockopt = compat_udpv6_getsockopt,
1090 #endif
1091 };
1092 
1093 static struct inet_protosw udpv6_protosw = {
1094 	.type =      SOCK_DGRAM,
1095 	.protocol =  IPPROTO_UDP,
1096 	.prot =      &udpv6_prot,
1097 	.ops =       &inet6_dgram_ops,
1098 	.capability =-1,
1099 	.no_check =  UDP_CSUM_DEFAULT,
1100 	.flags =     INET_PROTOSW_PERMANENT,
1101 };
1102 
1103 
1104 void __init udpv6_init(void)
1105 {
1106 	if (inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP) < 0)
1107 		printk(KERN_ERR "udpv6_init: Could not register protocol\n");
1108 	inet6_register_protosw(&udpv6_protosw);
1109 }
1110