3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
8 * Based on linux/ipv4/udp.c
11 * Hideaki YOSHIFUJI : sin6_scope_id support
12 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
13 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
14 * a single port at the same time.
15 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data
16 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file.
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/in6.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_arp.h>
32 #include <linux/ipv6.h>
33 #include <linux/icmpv6.h>
34 #include <linux/init.h>
35 #include <linux/module.h>
36 #include <linux/skbuff.h>
37 #include <linux/slab.h>
38 #include <asm/uaccess.h>
40 #include <net/ndisc.h>
41 #include <net/protocol.h>
42 #include <net/transp_v6.h>
43 #include <net/ip6_route.h>
45 #include <net/tcp_states.h>
46 #include <net/ip6_checksum.h>
48 #include <net/inet6_hashtables.h>
49 #include <net/busy_poll.h>
51 #include <linux/proc_fs.h>
52 #include <linux/seq_file.h>
53 #include <trace/events/skb.h>
56 static unsigned int udp6_ehashfn(struct net
*net
,
57 const struct in6_addr
*laddr
,
59 const struct in6_addr
*faddr
,
62 static u32 udp6_ehash_secret __read_mostly
;
63 static u32 udp_ipv6_hash_secret __read_mostly
;
67 net_get_random_once(&udp6_ehash_secret
,
68 sizeof(udp6_ehash_secret
));
69 net_get_random_once(&udp_ipv6_hash_secret
,
70 sizeof(udp_ipv6_hash_secret
));
72 lhash
= (__force u32
)laddr
->s6_addr32
[3];
73 fhash
= __ipv6_addr_jhash(faddr
, udp_ipv6_hash_secret
);
75 return __inet6_ehashfn(lhash
, lport
, fhash
, fport
,
76 udp_ipv6_hash_secret
+ net_hash_mix(net
));
79 int ipv6_rcv_saddr_equal(const struct sock
*sk
, const struct sock
*sk2
)
81 const struct in6_addr
*sk2_rcv_saddr6
= inet6_rcv_saddr(sk2
);
82 int sk2_ipv6only
= inet_v6_ipv6only(sk2
);
83 int addr_type
= ipv6_addr_type(&sk
->sk_v6_rcv_saddr
);
84 int addr_type2
= sk2_rcv_saddr6
? ipv6_addr_type(sk2_rcv_saddr6
) : IPV6_ADDR_MAPPED
;
86 /* if both are mapped, treat as IPv4 */
87 if (addr_type
== IPV6_ADDR_MAPPED
&& addr_type2
== IPV6_ADDR_MAPPED
)
88 return (!sk2_ipv6only
&&
89 (!sk
->sk_rcv_saddr
|| !sk2
->sk_rcv_saddr
||
90 sk
->sk_rcv_saddr
== sk2
->sk_rcv_saddr
));
92 if (addr_type2
== IPV6_ADDR_ANY
&&
93 !(sk2_ipv6only
&& addr_type
== IPV6_ADDR_MAPPED
))
96 if (addr_type
== IPV6_ADDR_ANY
&&
97 !(ipv6_only_sock(sk
) && addr_type2
== IPV6_ADDR_MAPPED
))
100 if (sk2_rcv_saddr6
&&
101 ipv6_addr_equal(&sk
->sk_v6_rcv_saddr
, sk2_rcv_saddr6
))
107 static unsigned int udp6_portaddr_hash(struct net
*net
,
108 const struct in6_addr
*addr6
,
111 unsigned int hash
, mix
= net_hash_mix(net
);
113 if (ipv6_addr_any(addr6
))
114 hash
= jhash_1word(0, mix
);
115 else if (ipv6_addr_v4mapped(addr6
))
116 hash
= jhash_1word((__force u32
)addr6
->s6_addr32
[3], mix
);
118 hash
= jhash2((__force u32
*)addr6
->s6_addr32
, 4, mix
);
124 int udp_v6_get_port(struct sock
*sk
, unsigned short snum
)
126 unsigned int hash2_nulladdr
=
127 udp6_portaddr_hash(sock_net(sk
), &in6addr_any
, snum
);
128 unsigned int hash2_partial
=
129 udp6_portaddr_hash(sock_net(sk
), &sk
->sk_v6_rcv_saddr
, 0);
131 /* precompute partial secondary hash */
132 udp_sk(sk
)->udp_portaddr_hash
= hash2_partial
;
133 return udp_lib_get_port(sk
, snum
, ipv6_rcv_saddr_equal
, hash2_nulladdr
);
136 static void udp_v6_rehash(struct sock
*sk
)
138 u16 new_hash
= udp6_portaddr_hash(sock_net(sk
),
139 &sk
->sk_v6_rcv_saddr
,
140 inet_sk(sk
)->inet_num
);
142 udp_lib_rehash(sk
, new_hash
);
145 static inline int compute_score(struct sock
*sk
, struct net
*net
,
147 const struct in6_addr
*saddr
, __be16 sport
,
148 const struct in6_addr
*daddr
, __be16 dport
,
153 if (net_eq(sock_net(sk
), net
) && udp_sk(sk
)->udp_port_hash
== hnum
&&
154 sk
->sk_family
== PF_INET6
) {
155 struct inet_sock
*inet
= inet_sk(sk
);
158 if (inet
->inet_dport
) {
159 if (inet
->inet_dport
!= sport
)
163 if (!ipv6_addr_any(&sk
->sk_v6_rcv_saddr
)) {
164 if (!ipv6_addr_equal(&sk
->sk_v6_rcv_saddr
, daddr
))
168 if (!ipv6_addr_any(&sk
->sk_v6_daddr
)) {
169 if (!ipv6_addr_equal(&sk
->sk_v6_daddr
, saddr
))
173 if (sk
->sk_bound_dev_if
) {
174 if (sk
->sk_bound_dev_if
!= dif
)
182 #define SCORE2_MAX (1 + 1 + 1)
183 static inline int compute_score2(struct sock
*sk
, struct net
*net
,
184 const struct in6_addr
*saddr
, __be16 sport
,
185 const struct in6_addr
*daddr
, unsigned short hnum
,
190 if (net_eq(sock_net(sk
), net
) && udp_sk(sk
)->udp_port_hash
== hnum
&&
191 sk
->sk_family
== PF_INET6
) {
192 struct inet_sock
*inet
= inet_sk(sk
);
194 if (!ipv6_addr_equal(&sk
->sk_v6_rcv_saddr
, daddr
))
197 if (inet
->inet_dport
) {
198 if (inet
->inet_dport
!= sport
)
202 if (!ipv6_addr_any(&sk
->sk_v6_daddr
)) {
203 if (!ipv6_addr_equal(&sk
->sk_v6_daddr
, saddr
))
207 if (sk
->sk_bound_dev_if
) {
208 if (sk
->sk_bound_dev_if
!= dif
)
217 /* called with read_rcu_lock() */
218 static struct sock
*udp6_lib_lookup2(struct net
*net
,
219 const struct in6_addr
*saddr
, __be16 sport
,
220 const struct in6_addr
*daddr
, unsigned int hnum
, int dif
,
221 struct udp_hslot
*hslot2
, unsigned int slot2
)
223 struct sock
*sk
, *result
;
224 struct hlist_nulls_node
*node
;
225 int score
, badness
, matches
= 0, reuseport
= 0;
231 udp_portaddr_for_each_entry_rcu(sk
, node
, &hslot2
->head
) {
232 score
= compute_score2(sk
, net
, saddr
, sport
,
234 if (score
> badness
) {
237 reuseport
= sk
->sk_reuseport
;
239 hash
= udp6_ehashfn(net
, daddr
, hnum
,
242 } else if (score
== SCORE2_MAX
)
244 } else if (score
== badness
&& reuseport
) {
246 if (((u64
)hash
* matches
) >> 32 == 0)
248 hash
= next_pseudo_random32(hash
);
252 * if the nulls value we got at the end of this lookup is
253 * not the expected one, we must restart lookup.
254 * We probably met an item that was moved to another chain.
256 if (get_nulls_value(node
) != slot2
)
261 if (unlikely(!atomic_inc_not_zero_hint(&result
->sk_refcnt
, 2)))
263 else if (unlikely(compute_score2(result
, net
, saddr
, sport
,
264 daddr
, hnum
, dif
) < badness
)) {
272 struct sock
*__udp6_lib_lookup(struct net
*net
,
273 const struct in6_addr
*saddr
, __be16 sport
,
274 const struct in6_addr
*daddr
, __be16 dport
,
275 int dif
, struct udp_table
*udptable
)
277 struct sock
*sk
, *result
;
278 struct hlist_nulls_node
*node
;
279 unsigned short hnum
= ntohs(dport
);
280 unsigned int hash2
, slot2
, slot
= udp_hashfn(net
, hnum
, udptable
->mask
);
281 struct udp_hslot
*hslot2
, *hslot
= &udptable
->hash
[slot
];
282 int score
, badness
, matches
= 0, reuseport
= 0;
286 if (hslot
->count
> 10) {
287 hash2
= udp6_portaddr_hash(net
, daddr
, hnum
);
288 slot2
= hash2
& udptable
->mask
;
289 hslot2
= &udptable
->hash2
[slot2
];
290 if (hslot
->count
< hslot2
->count
)
293 result
= udp6_lib_lookup2(net
, saddr
, sport
,
297 hash2
= udp6_portaddr_hash(net
, &in6addr_any
, hnum
);
298 slot2
= hash2
& udptable
->mask
;
299 hslot2
= &udptable
->hash2
[slot2
];
300 if (hslot
->count
< hslot2
->count
)
303 result
= udp6_lib_lookup2(net
, saddr
, sport
,
304 &in6addr_any
, hnum
, dif
,
313 sk_nulls_for_each_rcu(sk
, node
, &hslot
->head
) {
314 score
= compute_score(sk
, net
, hnum
, saddr
, sport
, daddr
, dport
, dif
);
315 if (score
> badness
) {
318 reuseport
= sk
->sk_reuseport
;
320 hash
= udp6_ehashfn(net
, daddr
, hnum
,
324 } else if (score
== badness
&& reuseport
) {
326 if (((u64
)hash
* matches
) >> 32 == 0)
328 hash
= next_pseudo_random32(hash
);
332 * if the nulls value we got at the end of this lookup is
333 * not the expected one, we must restart lookup.
334 * We probably met an item that was moved to another chain.
336 if (get_nulls_value(node
) != slot
)
340 if (unlikely(!atomic_inc_not_zero_hint(&result
->sk_refcnt
, 2)))
342 else if (unlikely(compute_score(result
, net
, hnum
, saddr
, sport
,
343 daddr
, dport
, dif
) < badness
)) {
351 EXPORT_SYMBOL_GPL(__udp6_lib_lookup
);
353 static struct sock
*__udp6_lib_lookup_skb(struct sk_buff
*skb
,
354 __be16 sport
, __be16 dport
,
355 struct udp_table
*udptable
)
358 const struct ipv6hdr
*iph
= ipv6_hdr(skb
);
360 if (unlikely(sk
= skb_steal_sock(skb
)))
362 return __udp6_lib_lookup(dev_net(skb_dst(skb
)->dev
), &iph
->saddr
, sport
,
363 &iph
->daddr
, dport
, inet6_iif(skb
),
367 struct sock
*udp6_lib_lookup(struct net
*net
, const struct in6_addr
*saddr
, __be16 sport
,
368 const struct in6_addr
*daddr
, __be16 dport
, int dif
)
370 return __udp6_lib_lookup(net
, saddr
, sport
, daddr
, dport
, dif
, &udp_table
);
372 EXPORT_SYMBOL_GPL(udp6_lib_lookup
);
376 * This should be easy, if there is something there we
377 * return it, otherwise we block.
380 int udpv6_recvmsg(struct kiocb
*iocb
, struct sock
*sk
,
381 struct msghdr
*msg
, size_t len
,
382 int noblock
, int flags
, int *addr_len
)
384 struct ipv6_pinfo
*np
= inet6_sk(sk
);
385 struct inet_sock
*inet
= inet_sk(sk
);
387 unsigned int ulen
, copied
;
390 int is_udplite
= IS_UDPLITE(sk
);
394 if (flags
& MSG_ERRQUEUE
)
395 return ipv6_recv_error(sk
, msg
, len
, addr_len
);
397 if (np
->rxpmtu
&& np
->rxopt
.bits
.rxpmtu
)
398 return ipv6_recv_rxpmtu(sk
, msg
, len
, addr_len
);
401 skb
= __skb_recv_datagram(sk
, flags
| (noblock
? MSG_DONTWAIT
: 0),
402 &peeked
, &off
, &err
);
406 ulen
= skb
->len
- sizeof(struct udphdr
);
410 else if (copied
< ulen
)
411 msg
->msg_flags
|= MSG_TRUNC
;
413 is_udp4
= (skb
->protocol
== htons(ETH_P_IP
));
416 * If checksum is needed at all, try to do it while copying the
417 * data. If the data is truncated, or if we only want a partial
418 * coverage checksum (UDP-Lite), do it before the copy.
421 if (copied
< ulen
|| UDP_SKB_CB(skb
)->partial_cov
) {
422 if (udp_lib_checksum_complete(skb
))
426 if (skb_csum_unnecessary(skb
))
427 err
= skb_copy_datagram_iovec(skb
, sizeof(struct udphdr
),
428 msg
->msg_iov
, copied
);
430 err
= skb_copy_and_csum_datagram_iovec(skb
, sizeof(struct udphdr
), msg
->msg_iov
);
435 trace_kfree_skb(skb
, udpv6_recvmsg
);
437 atomic_inc(&sk
->sk_drops
);
439 UDP_INC_STATS_USER(sock_net(sk
),
443 UDP6_INC_STATS_USER(sock_net(sk
),
451 UDP_INC_STATS_USER(sock_net(sk
),
452 UDP_MIB_INDATAGRAMS
, is_udplite
);
454 UDP6_INC_STATS_USER(sock_net(sk
),
455 UDP_MIB_INDATAGRAMS
, is_udplite
);
458 sock_recv_ts_and_drops(msg
, sk
, skb
);
460 /* Copy the address. */
462 DECLARE_SOCKADDR(struct sockaddr_in6
*, sin6
, msg
->msg_name
);
463 sin6
->sin6_family
= AF_INET6
;
464 sin6
->sin6_port
= udp_hdr(skb
)->source
;
465 sin6
->sin6_flowinfo
= 0;
468 ipv6_addr_set_v4mapped(ip_hdr(skb
)->saddr
,
470 sin6
->sin6_scope_id
= 0;
472 sin6
->sin6_addr
= ipv6_hdr(skb
)->saddr
;
473 sin6
->sin6_scope_id
=
474 ipv6_iface_scope_id(&sin6
->sin6_addr
,
477 *addr_len
= sizeof(*sin6
);
481 ip6_datagram_recv_common_ctl(sk
, msg
, skb
);
484 if (inet
->cmsg_flags
)
485 ip_cmsg_recv(msg
, skb
);
488 ip6_datagram_recv_specific_ctl(sk
, msg
, skb
);
492 if (flags
& MSG_TRUNC
)
496 skb_free_datagram_locked(sk
, skb
);
501 slow
= lock_sock_fast(sk
);
502 if (!skb_kill_datagram(sk
, skb
, flags
)) {
504 UDP_INC_STATS_USER(sock_net(sk
),
505 UDP_MIB_CSUMERRORS
, is_udplite
);
506 UDP_INC_STATS_USER(sock_net(sk
),
507 UDP_MIB_INERRORS
, is_udplite
);
509 UDP6_INC_STATS_USER(sock_net(sk
),
510 UDP_MIB_CSUMERRORS
, is_udplite
);
511 UDP6_INC_STATS_USER(sock_net(sk
),
512 UDP_MIB_INERRORS
, is_udplite
);
515 unlock_sock_fast(sk
, slow
);
520 /* starting over for a new packet */
521 msg
->msg_flags
&= ~MSG_TRUNC
;
525 void __udp6_lib_err(struct sk_buff
*skb
, struct inet6_skb_parm
*opt
,
526 u8 type
, u8 code
, int offset
, __be32 info
,
527 struct udp_table
*udptable
)
529 struct ipv6_pinfo
*np
;
530 const struct ipv6hdr
*hdr
= (const struct ipv6hdr
*)skb
->data
;
531 const struct in6_addr
*saddr
= &hdr
->saddr
;
532 const struct in6_addr
*daddr
= &hdr
->daddr
;
533 struct udphdr
*uh
= (struct udphdr
*)(skb
->data
+offset
);
536 struct net
*net
= dev_net(skb
->dev
);
538 sk
= __udp6_lib_lookup(net
, daddr
, uh
->dest
,
539 saddr
, uh
->source
, inet6_iif(skb
), udptable
);
541 ICMP6_INC_STATS_BH(net
, __in6_dev_get(skb
->dev
),
546 if (type
== ICMPV6_PKT_TOOBIG
) {
547 if (!ip6_sk_accept_pmtu(sk
))
549 ip6_sk_update_pmtu(skb
, sk
, info
);
551 if (type
== NDISC_REDIRECT
) {
552 ip6_sk_redirect(skb
, sk
);
558 if (!icmpv6_err_convert(type
, code
, &err
) && !np
->recverr
)
561 if (sk
->sk_state
!= TCP_ESTABLISHED
&& !np
->recverr
)
565 ipv6_icmp_error(sk
, skb
, err
, uh
->dest
, ntohl(info
), (u8
*)(uh
+1));
568 sk
->sk_error_report(sk
);
573 static int __udpv6_queue_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
)
577 if (!ipv6_addr_any(&sk
->sk_v6_daddr
)) {
578 sock_rps_save_rxhash(sk
, skb
);
579 sk_mark_napi_id(sk
, skb
);
582 rc
= sock_queue_rcv_skb(sk
, skb
);
584 int is_udplite
= IS_UDPLITE(sk
);
586 /* Note that an ENOMEM error is charged twice */
588 UDP6_INC_STATS_BH(sock_net(sk
),
589 UDP_MIB_RCVBUFERRORS
, is_udplite
);
590 UDP6_INC_STATS_BH(sock_net(sk
), UDP_MIB_INERRORS
, is_udplite
);
597 static __inline__
void udpv6_err(struct sk_buff
*skb
,
598 struct inet6_skb_parm
*opt
, u8 type
,
599 u8 code
, int offset
, __be32 info
)
601 __udp6_lib_err(skb
, opt
, type
, code
, offset
, info
, &udp_table
);
604 static struct static_key udpv6_encap_needed __read_mostly
;
605 void udpv6_encap_enable(void)
607 if (!static_key_enabled(&udpv6_encap_needed
))
608 static_key_slow_inc(&udpv6_encap_needed
);
610 EXPORT_SYMBOL(udpv6_encap_enable
);
612 int udpv6_queue_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
)
614 struct udp_sock
*up
= udp_sk(sk
);
616 int is_udplite
= IS_UDPLITE(sk
);
618 if (!xfrm6_policy_check(sk
, XFRM_POLICY_IN
, skb
))
621 if (static_key_false(&udpv6_encap_needed
) && up
->encap_type
) {
622 int (*encap_rcv
)(struct sock
*sk
, struct sk_buff
*skb
);
625 * This is an encapsulation socket so pass the skb to
626 * the socket's udp_encap_rcv() hook. Otherwise, just
627 * fall through and pass this up the UDP socket.
628 * up->encap_rcv() returns the following value:
629 * =0 if skb was successfully passed to the encap
630 * handler or was discarded by it.
631 * >0 if skb should be passed on to UDP.
632 * <0 if skb should be resubmitted as proto -N
635 /* if we're overly short, let UDP handle it */
636 encap_rcv
= ACCESS_ONCE(up
->encap_rcv
);
637 if (skb
->len
> sizeof(struct udphdr
) && encap_rcv
!= NULL
) {
640 /* Verify checksum before giving to encap */
641 if (udp_lib_checksum_complete(skb
))
644 ret
= encap_rcv(sk
, skb
);
646 UDP_INC_STATS_BH(sock_net(sk
),
653 /* FALLTHROUGH -- it's a UDP Packet */
657 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
659 if ((is_udplite
& UDPLITE_RECV_CC
) && UDP_SKB_CB(skb
)->partial_cov
) {
661 if (up
->pcrlen
== 0) { /* full coverage was set */
662 LIMIT_NETDEBUG(KERN_WARNING
"UDPLITE6: partial coverage"
663 " %d while full coverage %d requested\n",
664 UDP_SKB_CB(skb
)->cscov
, skb
->len
);
667 if (UDP_SKB_CB(skb
)->cscov
< up
->pcrlen
) {
668 LIMIT_NETDEBUG(KERN_WARNING
"UDPLITE6: coverage %d "
669 "too small, need min %d\n",
670 UDP_SKB_CB(skb
)->cscov
, up
->pcrlen
);
675 if (rcu_access_pointer(sk
->sk_filter
)) {
676 if (udp_lib_checksum_complete(skb
))
680 if (sk_rcvqueues_full(sk
, sk
->sk_rcvbuf
)) {
681 UDP6_INC_STATS_BH(sock_net(sk
),
682 UDP_MIB_RCVBUFERRORS
, is_udplite
);
690 if (!sock_owned_by_user(sk
))
691 rc
= __udpv6_queue_rcv_skb(sk
, skb
);
692 else if (sk_add_backlog(sk
, skb
, sk
->sk_rcvbuf
)) {
701 UDP6_INC_STATS_BH(sock_net(sk
), UDP_MIB_CSUMERRORS
, is_udplite
);
703 UDP6_INC_STATS_BH(sock_net(sk
), UDP_MIB_INERRORS
, is_udplite
);
704 atomic_inc(&sk
->sk_drops
);
709 static bool __udp_v6_is_mcast_sock(struct net
*net
, struct sock
*sk
,
710 __be16 loc_port
, const struct in6_addr
*loc_addr
,
711 __be16 rmt_port
, const struct in6_addr
*rmt_addr
,
712 int dif
, unsigned short hnum
)
714 struct inet_sock
*inet
= inet_sk(sk
);
716 if (!net_eq(sock_net(sk
), net
))
719 if (udp_sk(sk
)->udp_port_hash
!= hnum
||
720 sk
->sk_family
!= PF_INET6
||
721 (inet
->inet_dport
&& inet
->inet_dport
!= rmt_port
) ||
722 (!ipv6_addr_any(&sk
->sk_v6_daddr
) &&
723 !ipv6_addr_equal(&sk
->sk_v6_daddr
, rmt_addr
)) ||
724 (sk
->sk_bound_dev_if
&& sk
->sk_bound_dev_if
!= dif
))
726 if (!inet6_mc_check(sk
, loc_addr
, rmt_addr
))
731 static void flush_stack(struct sock
**stack
, unsigned int count
,
732 struct sk_buff
*skb
, unsigned int final
)
734 struct sk_buff
*skb1
= NULL
;
738 for (i
= 0; i
< count
; i
++) {
740 if (likely(skb1
== NULL
))
741 skb1
= (i
== final
) ? skb
: skb_clone(skb
, GFP_ATOMIC
);
743 atomic_inc(&sk
->sk_drops
);
744 UDP6_INC_STATS_BH(sock_net(sk
), UDP_MIB_RCVBUFERRORS
,
746 UDP6_INC_STATS_BH(sock_net(sk
), UDP_MIB_INERRORS
,
750 if (skb1
&& udpv6_queue_rcv_skb(sk
, skb1
) <= 0)
758 static void udp6_csum_zero_error(struct sk_buff
*skb
)
760 /* RFC 2460 section 8.1 says that we SHOULD log
761 * this error. Well, it is reasonable.
763 LIMIT_NETDEBUG(KERN_INFO
"IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
764 &ipv6_hdr(skb
)->saddr
, ntohs(udp_hdr(skb
)->source
),
765 &ipv6_hdr(skb
)->daddr
, ntohs(udp_hdr(skb
)->dest
));
769 * Note: called only from the BH handler context,
770 * so we don't need to lock the hashes.
772 static int __udp6_lib_mcast_deliver(struct net
*net
, struct sk_buff
*skb
,
773 const struct in6_addr
*saddr
, const struct in6_addr
*daddr
,
774 struct udp_table
*udptable
)
776 struct sock
*sk
, *stack
[256 / sizeof(struct sock
*)];
777 const struct udphdr
*uh
= udp_hdr(skb
);
778 struct hlist_nulls_node
*node
;
779 unsigned short hnum
= ntohs(uh
->dest
);
780 struct udp_hslot
*hslot
= udp_hashslot(udptable
, net
, hnum
);
781 int dif
= inet6_iif(skb
);
782 unsigned int count
= 0, offset
= offsetof(typeof(*sk
), sk_nulls_node
);
783 unsigned int hash2
= 0, hash2_any
= 0, use_hash2
= (hslot
->count
> 10);
786 hash2_any
= udp6_portaddr_hash(net
, &in6addr_any
, hnum
) &
788 hash2
= udp6_portaddr_hash(net
, daddr
, hnum
) & udp_table
.mask
;
790 hslot
= &udp_table
.hash2
[hash2
];
791 offset
= offsetof(typeof(*sk
), __sk_common
.skc_portaddr_node
);
794 spin_lock(&hslot
->lock
);
795 sk_nulls_for_each_entry_offset(sk
, node
, &hslot
->head
, offset
) {
796 if (__udp_v6_is_mcast_sock(net
, sk
,
800 /* If zero checksum and no_check is not on for
801 * the socket then skip it.
803 (uh
->check
|| udp_sk(sk
)->no_check6_rx
)) {
804 if (unlikely(count
== ARRAY_SIZE(stack
))) {
805 flush_stack(stack
, count
, skb
, ~0);
813 spin_unlock(&hslot
->lock
);
815 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
816 if (use_hash2
&& hash2
!= hash2_any
) {
822 flush_stack(stack
, count
, skb
, count
- 1);
829 int __udp6_lib_rcv(struct sk_buff
*skb
, struct udp_table
*udptable
,
832 struct net
*net
= dev_net(skb
->dev
);
835 const struct in6_addr
*saddr
, *daddr
;
838 if (!pskb_may_pull(skb
, sizeof(struct udphdr
)))
841 saddr
= &ipv6_hdr(skb
)->saddr
;
842 daddr
= &ipv6_hdr(skb
)->daddr
;
845 ulen
= ntohs(uh
->len
);
849 if (proto
== IPPROTO_UDP
) {
850 /* UDP validates ulen. */
852 /* Check for jumbo payload */
856 if (ulen
< sizeof(*uh
))
859 if (ulen
< skb
->len
) {
860 if (pskb_trim_rcsum(skb
, ulen
))
862 saddr
= &ipv6_hdr(skb
)->saddr
;
863 daddr
= &ipv6_hdr(skb
)->daddr
;
868 if (udp6_csum_init(skb
, uh
, proto
))
872 * Multicast receive code
874 if (ipv6_addr_is_multicast(daddr
))
875 return __udp6_lib_mcast_deliver(net
, skb
,
876 saddr
, daddr
, udptable
);
881 * check socket cache ... must talk to Alan about his plans
882 * for sock caches... i'll skip this for now.
884 sk
= __udp6_lib_lookup_skb(skb
, uh
->source
, uh
->dest
, udptable
);
888 if (!uh
->check
&& !udp_sk(sk
)->no_check6_rx
) {
890 udp6_csum_zero_error(skb
);
894 ret
= udpv6_queue_rcv_skb(sk
, skb
);
897 /* a return value > 0 means to resubmit the input, but
898 * it wants the return to be -protocol, or 0
907 udp6_csum_zero_error(skb
);
911 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
914 if (udp_lib_checksum_complete(skb
))
917 UDP6_INC_STATS_BH(net
, UDP_MIB_NOPORTS
, proto
== IPPROTO_UDPLITE
);
918 icmpv6_send(skb
, ICMPV6_DEST_UNREACH
, ICMPV6_PORT_UNREACH
, 0);
924 LIMIT_NETDEBUG(KERN_DEBUG
"UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
925 proto
== IPPROTO_UDPLITE
? "-Lite" : "",
934 UDP6_INC_STATS_BH(net
, UDP_MIB_CSUMERRORS
, proto
== IPPROTO_UDPLITE
);
936 UDP6_INC_STATS_BH(net
, UDP_MIB_INERRORS
, proto
== IPPROTO_UDPLITE
);
941 static __inline__
int udpv6_rcv(struct sk_buff
*skb
)
943 return __udp6_lib_rcv(skb
, &udp_table
, IPPROTO_UDP
);
947 * Throw away all pending data and cancel the corking. Socket is locked.
949 static void udp_v6_flush_pending_frames(struct sock
*sk
)
951 struct udp_sock
*up
= udp_sk(sk
);
953 if (up
->pending
== AF_INET
)
954 udp_flush_pending_frames(sk
);
955 else if (up
->pending
) {
958 ip6_flush_pending_frames(sk
);
963 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
964 * @sk: socket we are sending on
965 * @skb: sk_buff containing the filled-in UDP header
966 * (checksum field must be zeroed out)
968 static void udp6_hwcsum_outgoing(struct sock
*sk
, struct sk_buff
*skb
,
969 const struct in6_addr
*saddr
,
970 const struct in6_addr
*daddr
, int len
)
973 struct udphdr
*uh
= udp_hdr(skb
);
976 if (skb_queue_len(&sk
->sk_write_queue
) == 1) {
977 /* Only one fragment on the socket. */
978 skb
->csum_start
= skb_transport_header(skb
) - skb
->head
;
979 skb
->csum_offset
= offsetof(struct udphdr
, check
);
980 uh
->check
= ~csum_ipv6_magic(saddr
, daddr
, len
, IPPROTO_UDP
, 0);
983 * HW-checksum won't work as there are two or more
984 * fragments on the socket so that all csums of sk_buffs
987 offset
= skb_transport_offset(skb
);
988 skb
->csum
= skb_checksum(skb
, offset
, skb
->len
- offset
, 0);
990 skb
->ip_summed
= CHECKSUM_NONE
;
992 skb_queue_walk(&sk
->sk_write_queue
, skb
) {
993 csum
= csum_add(csum
, skb
->csum
);
996 uh
->check
= csum_ipv6_magic(saddr
, daddr
, len
, IPPROTO_UDP
,
999 uh
->check
= CSUM_MANGLED_0
;
1007 static int udp_v6_push_pending_frames(struct sock
*sk
)
1009 struct sk_buff
*skb
;
1011 struct udp_sock
*up
= udp_sk(sk
);
1012 struct inet_sock
*inet
= inet_sk(sk
);
1015 int is_udplite
= IS_UDPLITE(sk
);
1018 if (up
->pending
== AF_INET
)
1019 return udp_push_pending_frames(sk
);
1021 fl6
= &inet
->cork
.fl
.u
.ip6
;
1023 /* Grab the skbuff where UDP header space exists. */
1024 if ((skb
= skb_peek(&sk
->sk_write_queue
)) == NULL
)
1028 * Create a UDP header
1031 uh
->source
= fl6
->fl6_sport
;
1032 uh
->dest
= fl6
->fl6_dport
;
1033 uh
->len
= htons(up
->len
);
1037 csum
= udplite_csum_outgoing(sk
, skb
);
1038 else if (up
->no_check6_tx
) { /* UDP csum disabled */
1039 skb
->ip_summed
= CHECKSUM_NONE
;
1041 } else if (skb
->ip_summed
== CHECKSUM_PARTIAL
) { /* UDP hardware csum */
1042 udp6_hwcsum_outgoing(sk
, skb
, &fl6
->saddr
, &fl6
->daddr
,
1046 csum
= udp_csum_outgoing(sk
, skb
);
1048 /* add protocol-dependent pseudo-header */
1049 uh
->check
= csum_ipv6_magic(&fl6
->saddr
, &fl6
->daddr
,
1050 up
->len
, fl6
->flowi6_proto
, csum
);
1052 uh
->check
= CSUM_MANGLED_0
;
1055 err
= ip6_push_pending_frames(sk
);
1057 if (err
== -ENOBUFS
&& !inet6_sk(sk
)->recverr
) {
1058 UDP6_INC_STATS_USER(sock_net(sk
),
1059 UDP_MIB_SNDBUFERRORS
, is_udplite
);
1063 UDP6_INC_STATS_USER(sock_net(sk
),
1064 UDP_MIB_OUTDATAGRAMS
, is_udplite
);
1071 int udpv6_sendmsg(struct kiocb
*iocb
, struct sock
*sk
,
1072 struct msghdr
*msg
, size_t len
)
1074 struct ipv6_txoptions opt_space
;
1075 struct udp_sock
*up
= udp_sk(sk
);
1076 struct inet_sock
*inet
= inet_sk(sk
);
1077 struct ipv6_pinfo
*np
= inet6_sk(sk
);
1078 DECLARE_SOCKADDR(struct sockaddr_in6
*, sin6
, msg
->msg_name
);
1079 struct in6_addr
*daddr
, *final_p
, final
;
1080 struct ipv6_txoptions
*opt
= NULL
;
1081 struct ip6_flowlabel
*flowlabel
= NULL
;
1083 struct dst_entry
*dst
;
1084 int addr_len
= msg
->msg_namelen
;
1089 int corkreq
= up
->corkflag
|| msg
->msg_flags
&MSG_MORE
;
1092 int is_udplite
= IS_UDPLITE(sk
);
1093 int (*getfrag
)(void *, char *, int, int, int, struct sk_buff
*);
1095 /* destination address check */
1097 if (addr_len
< offsetof(struct sockaddr
, sa_data
))
1100 switch (sin6
->sin6_family
) {
1102 if (addr_len
< SIN6_LEN_RFC2133
)
1104 daddr
= &sin6
->sin6_addr
;
1107 goto do_udp_sendmsg
;
1109 msg
->msg_name
= sin6
= NULL
;
1110 msg
->msg_namelen
= addr_len
= 0;
1116 } else if (!up
->pending
) {
1117 if (sk
->sk_state
!= TCP_ESTABLISHED
)
1118 return -EDESTADDRREQ
;
1119 daddr
= &sk
->sk_v6_daddr
;
1124 if (ipv6_addr_v4mapped(daddr
)) {
1125 struct sockaddr_in sin
;
1126 sin
.sin_family
= AF_INET
;
1127 sin
.sin_port
= sin6
? sin6
->sin6_port
: inet
->inet_dport
;
1128 sin
.sin_addr
.s_addr
= daddr
->s6_addr32
[3];
1129 msg
->msg_name
= &sin
;
1130 msg
->msg_namelen
= sizeof(sin
);
1132 if (__ipv6_only_sock(sk
))
1133 return -ENETUNREACH
;
1134 return udp_sendmsg(iocb
, sk
, msg
, len
);
1138 if (up
->pending
== AF_INET
)
1139 return udp_sendmsg(iocb
, sk
, msg
, len
);
1141 /* Rough check on arithmetic overflow,
1142 better check is made in ip6_append_data().
1144 if (len
> INT_MAX
- sizeof(struct udphdr
))
1149 * There are pending frames.
1150 * The socket lock must be held while it's corked.
1153 if (likely(up
->pending
)) {
1154 if (unlikely(up
->pending
!= AF_INET6
)) {
1156 return -EAFNOSUPPORT
;
1159 goto do_append_data
;
1163 ulen
+= sizeof(struct udphdr
);
1165 memset(&fl6
, 0, sizeof(fl6
));
1168 if (sin6
->sin6_port
== 0)
1171 fl6
.fl6_dport
= sin6
->sin6_port
;
1172 daddr
= &sin6
->sin6_addr
;
1175 fl6
.flowlabel
= sin6
->sin6_flowinfo
&IPV6_FLOWINFO_MASK
;
1176 if (fl6
.flowlabel
&IPV6_FLOWLABEL_MASK
) {
1177 flowlabel
= fl6_sock_lookup(sk
, fl6
.flowlabel
);
1178 if (flowlabel
== NULL
)
1184 * Otherwise it will be difficult to maintain
1187 if (sk
->sk_state
== TCP_ESTABLISHED
&&
1188 ipv6_addr_equal(daddr
, &sk
->sk_v6_daddr
))
1189 daddr
= &sk
->sk_v6_daddr
;
1191 if (addr_len
>= sizeof(struct sockaddr_in6
) &&
1192 sin6
->sin6_scope_id
&&
1193 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr
)))
1194 fl6
.flowi6_oif
= sin6
->sin6_scope_id
;
1196 if (sk
->sk_state
!= TCP_ESTABLISHED
)
1197 return -EDESTADDRREQ
;
1199 fl6
.fl6_dport
= inet
->inet_dport
;
1200 daddr
= &sk
->sk_v6_daddr
;
1201 fl6
.flowlabel
= np
->flow_label
;
1205 if (!fl6
.flowi6_oif
)
1206 fl6
.flowi6_oif
= sk
->sk_bound_dev_if
;
1208 if (!fl6
.flowi6_oif
)
1209 fl6
.flowi6_oif
= np
->sticky_pktinfo
.ipi6_ifindex
;
1211 fl6
.flowi6_mark
= sk
->sk_mark
;
1213 if (msg
->msg_controllen
) {
1215 memset(opt
, 0, sizeof(struct ipv6_txoptions
));
1216 opt
->tot_len
= sizeof(*opt
);
1218 err
= ip6_datagram_send_ctl(sock_net(sk
), sk
, msg
, &fl6
, opt
,
1219 &hlimit
, &tclass
, &dontfrag
);
1221 fl6_sock_release(flowlabel
);
1224 if ((fl6
.flowlabel
&IPV6_FLOWLABEL_MASK
) && !flowlabel
) {
1225 flowlabel
= fl6_sock_lookup(sk
, fl6
.flowlabel
);
1226 if (flowlabel
== NULL
)
1229 if (!(opt
->opt_nflen
|opt
->opt_flen
))
1236 opt
= fl6_merge_options(&opt_space
, flowlabel
, opt
);
1237 opt
= ipv6_fixup_options(&opt_space
, opt
);
1239 fl6
.flowi6_proto
= sk
->sk_protocol
;
1240 if (!ipv6_addr_any(daddr
))
1243 fl6
.daddr
.s6_addr
[15] = 0x1; /* :: means loopback (BSD'ism) */
1244 if (ipv6_addr_any(&fl6
.saddr
) && !ipv6_addr_any(&np
->saddr
))
1245 fl6
.saddr
= np
->saddr
;
1246 fl6
.fl6_sport
= inet
->inet_sport
;
1248 final_p
= fl6_update_dst(&fl6
, opt
, &final
);
1252 if (!fl6
.flowi6_oif
&& ipv6_addr_is_multicast(&fl6
.daddr
)) {
1253 fl6
.flowi6_oif
= np
->mcast_oif
;
1255 } else if (!fl6
.flowi6_oif
)
1256 fl6
.flowi6_oif
= np
->ucast_oif
;
1258 security_sk_classify_flow(sk
, flowi6_to_flowi(&fl6
));
1260 dst
= ip6_sk_dst_lookup_flow(sk
, &fl6
, final_p
);
1268 hlimit
= ip6_sk_dst_hoplimit(np
, &fl6
, dst
);
1271 tclass
= np
->tclass
;
1273 if (msg
->msg_flags
&MSG_CONFIRM
)
1278 if (unlikely(up
->pending
)) {
1279 /* The socket is already corked while preparing it. */
1280 /* ... which is an evident application bug. --ANK */
1283 LIMIT_NETDEBUG(KERN_DEBUG
"udp cork app bug 2\n");
1288 up
->pending
= AF_INET6
;
1292 dontfrag
= np
->dontfrag
;
1294 getfrag
= is_udplite
? udplite_getfrag
: ip_generic_getfrag
;
1295 err
= ip6_append_data(sk
, getfrag
, msg
->msg_iov
, ulen
,
1296 sizeof(struct udphdr
), hlimit
, tclass
, opt
, &fl6
,
1297 (struct rt6_info
*)dst
,
1298 corkreq
? msg
->msg_flags
|MSG_MORE
: msg
->msg_flags
, dontfrag
);
1300 udp_v6_flush_pending_frames(sk
);
1302 err
= udp_v6_push_pending_frames(sk
);
1303 else if (unlikely(skb_queue_empty(&sk
->sk_write_queue
)))
1308 ip6_dst_store(sk
, dst
,
1309 ipv6_addr_equal(&fl6
.daddr
, &sk
->sk_v6_daddr
) ?
1310 &sk
->sk_v6_daddr
: NULL
,
1311 #ifdef CONFIG_IPV6_SUBTREES
1312 ipv6_addr_equal(&fl6
.saddr
, &np
->saddr
) ?
1323 err
= np
->recverr
? net_xmit_errno(err
) : 0;
1327 fl6_sock_release(flowlabel
);
1331 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1332 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1333 * we don't have a good statistic (IpOutDiscards but it can be too many
1334 * things). We could add another new stat but at least for now that
1335 * seems like overkill.
1337 if (err
== -ENOBUFS
|| test_bit(SOCK_NOSPACE
, &sk
->sk_socket
->flags
)) {
1338 UDP6_INC_STATS_USER(sock_net(sk
),
1339 UDP_MIB_SNDBUFERRORS
, is_udplite
);
1345 if (!(msg
->msg_flags
&MSG_PROBE
) || len
)
1346 goto back_from_confirm
;
1351 void udpv6_destroy_sock(struct sock
*sk
)
1353 struct udp_sock
*up
= udp_sk(sk
);
1355 udp_v6_flush_pending_frames(sk
);
1358 if (static_key_false(&udpv6_encap_needed
) && up
->encap_type
) {
1359 void (*encap_destroy
)(struct sock
*sk
);
1360 encap_destroy
= ACCESS_ONCE(up
->encap_destroy
);
1365 inet6_destroy_sock(sk
);
1369 * Socket option code for UDP
1371 int udpv6_setsockopt(struct sock
*sk
, int level
, int optname
,
1372 char __user
*optval
, unsigned int optlen
)
1374 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1375 return udp_lib_setsockopt(sk
, level
, optname
, optval
, optlen
,
1376 udp_v6_push_pending_frames
);
1377 return ipv6_setsockopt(sk
, level
, optname
, optval
, optlen
);
1380 #ifdef CONFIG_COMPAT
1381 int compat_udpv6_setsockopt(struct sock
*sk
, int level
, int optname
,
1382 char __user
*optval
, unsigned int optlen
)
1384 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1385 return udp_lib_setsockopt(sk
, level
, optname
, optval
, optlen
,
1386 udp_v6_push_pending_frames
);
1387 return compat_ipv6_setsockopt(sk
, level
, optname
, optval
, optlen
);
1391 int udpv6_getsockopt(struct sock
*sk
, int level
, int optname
,
1392 char __user
*optval
, int __user
*optlen
)
1394 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1395 return udp_lib_getsockopt(sk
, level
, optname
, optval
, optlen
);
1396 return ipv6_getsockopt(sk
, level
, optname
, optval
, optlen
);
1399 #ifdef CONFIG_COMPAT
1400 int compat_udpv6_getsockopt(struct sock
*sk
, int level
, int optname
,
1401 char __user
*optval
, int __user
*optlen
)
1403 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
1404 return udp_lib_getsockopt(sk
, level
, optname
, optval
, optlen
);
1405 return compat_ipv6_getsockopt(sk
, level
, optname
, optval
, optlen
);
1409 static const struct inet6_protocol udpv6_protocol
= {
1410 .handler
= udpv6_rcv
,
1411 .err_handler
= udpv6_err
,
1412 .flags
= INET6_PROTO_NOPOLICY
|INET6_PROTO_FINAL
,
1415 /* ------------------------------------------------------------------------ */
1416 #ifdef CONFIG_PROC_FS
1417 int udp6_seq_show(struct seq_file
*seq
, void *v
)
1419 if (v
== SEQ_START_TOKEN
) {
1420 seq_puts(seq
, IPV6_SEQ_DGRAM_HEADER
);
1422 int bucket
= ((struct udp_iter_state
*)seq
->private)->bucket
;
1423 struct inet_sock
*inet
= inet_sk(v
);
1424 __u16 srcp
= ntohs(inet
->inet_sport
);
1425 __u16 destp
= ntohs(inet
->inet_dport
);
1426 ip6_dgram_sock_seq_show(seq
, v
, srcp
, destp
, bucket
);
1431 static const struct file_operations udp6_afinfo_seq_fops
= {
1432 .owner
= THIS_MODULE
,
1433 .open
= udp_seq_open
,
1435 .llseek
= seq_lseek
,
1436 .release
= seq_release_net
1439 static struct udp_seq_afinfo udp6_seq_afinfo
= {
1442 .udp_table
= &udp_table
,
1443 .seq_fops
= &udp6_afinfo_seq_fops
,
1445 .show
= udp6_seq_show
,
1449 int __net_init
udp6_proc_init(struct net
*net
)
1451 return udp_proc_register(net
, &udp6_seq_afinfo
);
1454 void udp6_proc_exit(struct net
*net
) {
1455 udp_proc_unregister(net
, &udp6_seq_afinfo
);
1457 #endif /* CONFIG_PROC_FS */
1459 void udp_v6_clear_sk(struct sock
*sk
, int size
)
1461 struct inet_sock
*inet
= inet_sk(sk
);
1463 /* we do not want to clear pinet6 field, because of RCU lookups */
1464 sk_prot_clear_portaddr_nulls(sk
, offsetof(struct inet_sock
, pinet6
));
1466 size
-= offsetof(struct inet_sock
, pinet6
) + sizeof(inet
->pinet6
);
1467 memset(&inet
->pinet6
+ 1, 0, size
);
1470 /* ------------------------------------------------------------------------ */
1472 struct proto udpv6_prot
= {
1474 .owner
= THIS_MODULE
,
1475 .close
= udp_lib_close
,
1476 .connect
= ip6_datagram_connect
,
1477 .disconnect
= udp_disconnect
,
1479 .destroy
= udpv6_destroy_sock
,
1480 .setsockopt
= udpv6_setsockopt
,
1481 .getsockopt
= udpv6_getsockopt
,
1482 .sendmsg
= udpv6_sendmsg
,
1483 .recvmsg
= udpv6_recvmsg
,
1484 .backlog_rcv
= __udpv6_queue_rcv_skb
,
1485 .hash
= udp_lib_hash
,
1486 .unhash
= udp_lib_unhash
,
1487 .rehash
= udp_v6_rehash
,
1488 .get_port
= udp_v6_get_port
,
1489 .memory_allocated
= &udp_memory_allocated
,
1490 .sysctl_mem
= sysctl_udp_mem
,
1491 .sysctl_wmem
= &sysctl_udp_wmem_min
,
1492 .sysctl_rmem
= &sysctl_udp_rmem_min
,
1493 .obj_size
= sizeof(struct udp6_sock
),
1494 .slab_flags
= SLAB_DESTROY_BY_RCU
,
1495 .h
.udp_table
= &udp_table
,
1496 #ifdef CONFIG_COMPAT
1497 .compat_setsockopt
= compat_udpv6_setsockopt
,
1498 .compat_getsockopt
= compat_udpv6_getsockopt
,
1500 .clear_sk
= udp_v6_clear_sk
,
1503 static struct inet_protosw udpv6_protosw
= {
1505 .protocol
= IPPROTO_UDP
,
1506 .prot
= &udpv6_prot
,
1507 .ops
= &inet6_dgram_ops
,
1508 .flags
= INET_PROTOSW_PERMANENT
,
1512 int __init
udpv6_init(void)
1516 ret
= inet6_add_protocol(&udpv6_protocol
, IPPROTO_UDP
);
1520 ret
= inet6_register_protosw(&udpv6_protosw
);
1522 goto out_udpv6_protocol
;
1527 inet6_del_protocol(&udpv6_protocol
, IPPROTO_UDP
);
1531 void udpv6_exit(void)
1533 inet6_unregister_protosw(&udpv6_protosw
);
1534 inet6_del_protocol(&udpv6_protocol
, IPPROTO_UDP
);