2 * IPv6 output functions
3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
8 * Based on linux/net/ipv4/ip_output.c
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
16 * A.N.Kuznetsov : airthmetics in fragmentation.
17 * extension headers are implemented.
18 * route changes now work.
19 * ip6_forward does not confuse sniffers.
22 * H. von Brand : Added missing #include <linux/string.h>
23 * Imran Patel : frag id should be in NBO
24 * Kazunori MIYAZAWA @USAGI
25 * : add ip6_append_data and related functions
29 #include <linux/errno.h>
30 #include <linux/kernel.h>
31 #include <linux/string.h>
32 #include <linux/socket.h>
33 #include <linux/net.h>
34 #include <linux/netdevice.h>
35 #include <linux/if_arp.h>
36 #include <linux/in6.h>
37 #include <linux/tcp.h>
38 #include <linux/route.h>
39 #include <linux/module.h>
40 #include <linux/slab.h>
42 #include <linux/netfilter.h>
43 #include <linux/netfilter_ipv6.h>
49 #include <net/ndisc.h>
50 #include <net/protocol.h>
51 #include <net/ip6_route.h>
52 #include <net/addrconf.h>
53 #include <net/rawv6.h>
56 #include <net/checksum.h>
57 #include <linux/mroute6.h>
58 #include <net/l3mdev.h>
60 static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb)
62 struct dst_entry *dst = skb_dst(skb);
63 struct net_device *dev = dst->dev;
64 struct neighbour *neigh;
65 struct in6_addr *nexthop;
68 skb->protocol = htons(ETH_P_IPV6);
71 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
72 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
74 if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(sk) &&
75 ((mroute6_socket(net, skb) &&
76 !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||
77 ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
78 &ipv6_hdr(skb)->saddr))) {
79 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
81 /* Do not check for IFF_ALLMULTI; multicast routing
82 is not supported in any case.
85 NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING,
86 net, sk, newskb, NULL, newskb->dev,
89 if (ipv6_hdr(skb)->hop_limit == 0) {
90 IP6_INC_STATS(net, idev,
91 IPSTATS_MIB_OUTDISCARDS);
97 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, skb->len);
99 if (IPV6_ADDR_MC_SCOPE(&ipv6_hdr(skb)->daddr) <=
100 IPV6_ADDR_SCOPE_NODELOCAL &&
101 !(dev->flags & IFF_LOOPBACK)) {
108 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
109 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
110 if (unlikely(!neigh))
111 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
112 if (!IS_ERR(neigh)) {
113 ret = dst_neigh_output(dst, neigh, skb);
114 rcu_read_unlock_bh();
117 rcu_read_unlock_bh();
119 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
124 static int ip6_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
126 if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
127 dst_allfrag(skb_dst(skb)) ||
128 (IP6CB(skb)->frag_max_size && skb->len > IP6CB(skb)->frag_max_size))
129 return ip6_fragment(net, sk, skb, ip6_finish_output2);
131 return ip6_finish_output2(net, sk, skb);
134 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
136 struct net_device *dev = skb_dst(skb)->dev;
137 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
139 if (unlikely(idev->cnf.disable_ipv6)) {
140 IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
145 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
146 net, sk, skb, NULL, dev,
148 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
152 * xmit an sk_buff (used by TCP, SCTP and DCCP)
153 * Note : socket lock is not held for SYNACK packets, but might be modified
154 * by calls to skb_set_owner_w() and ipv6_local_error(),
155 * which are using proper atomic operations or spinlocks.
157 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
158 struct ipv6_txoptions *opt, int tclass)
160 struct net *net = sock_net(sk);
161 const struct ipv6_pinfo *np = inet6_sk(sk);
162 struct in6_addr *first_hop = &fl6->daddr;
163 struct dst_entry *dst = skb_dst(skb);
165 u8 proto = fl6->flowi6_proto;
166 int seg_len = skb->len;
171 unsigned int head_room;
173 /* First: exthdrs may take lots of space (~8K for now)
174 MAX_HEADER is not enough.
176 head_room = opt->opt_nflen + opt->opt_flen;
177 seg_len += head_room;
178 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
180 if (skb_headroom(skb) < head_room) {
181 struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
183 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
184 IPSTATS_MIB_OUTDISCARDS);
190 /* skb_set_owner_w() changes sk->sk_wmem_alloc atomically,
191 * it is safe to call in our context (socket lock not held)
193 skb_set_owner_w(skb, (struct sock *)sk);
196 ipv6_push_frag_opts(skb, opt, &proto);
198 ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
201 skb_push(skb, sizeof(struct ipv6hdr));
202 skb_reset_network_header(skb);
206 * Fill in the IPv6 header
209 hlimit = np->hop_limit;
211 hlimit = ip6_dst_hoplimit(dst);
213 ip6_flow_hdr(hdr, tclass, ip6_make_flowlabel(net, skb, fl6->flowlabel,
214 np->autoflowlabel, fl6));
216 hdr->payload_len = htons(seg_len);
217 hdr->nexthdr = proto;
218 hdr->hop_limit = hlimit;
220 hdr->saddr = fl6->saddr;
221 hdr->daddr = *first_hop;
223 skb->protocol = htons(ETH_P_IPV6);
224 skb->priority = sk->sk_priority;
225 skb->mark = sk->sk_mark;
228 if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) {
229 IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
230 IPSTATS_MIB_OUT, skb->len);
231 /* hooks should never assume socket lock is held.
232 * we promote our socket to non const
234 return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
235 net, (struct sock *)sk, skb, NULL, dst->dev,
240 /* ipv6_local_error() does not require socket lock,
241 * we promote our socket to non const
243 ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu);
245 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
249 EXPORT_SYMBOL(ip6_xmit);
251 static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
253 struct ip6_ra_chain *ra;
254 struct sock *last = NULL;
256 read_lock(&ip6_ra_lock);
257 for (ra = ip6_ra_chain; ra; ra = ra->next) {
258 struct sock *sk = ra->sk;
259 if (sk && ra->sel == sel &&
260 (!sk->sk_bound_dev_if ||
261 sk->sk_bound_dev_if == skb->dev->ifindex)) {
263 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
265 rawv6_rcv(last, skb2);
272 rawv6_rcv(last, skb);
273 read_unlock(&ip6_ra_lock);
276 read_unlock(&ip6_ra_lock);
280 static int ip6_forward_proxy_check(struct sk_buff *skb)
282 struct ipv6hdr *hdr = ipv6_hdr(skb);
283 u8 nexthdr = hdr->nexthdr;
287 if (ipv6_ext_hdr(nexthdr)) {
288 offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr, &frag_off);
292 offset = sizeof(struct ipv6hdr);
294 if (nexthdr == IPPROTO_ICMPV6) {
295 struct icmp6hdr *icmp6;
297 if (!pskb_may_pull(skb, (skb_network_header(skb) +
298 offset + 1 - skb->data)))
301 icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
303 switch (icmp6->icmp6_type) {
304 case NDISC_ROUTER_SOLICITATION:
305 case NDISC_ROUTER_ADVERTISEMENT:
306 case NDISC_NEIGHBOUR_SOLICITATION:
307 case NDISC_NEIGHBOUR_ADVERTISEMENT:
309 /* For reaction involving unicast neighbor discovery
310 * message destined to the proxied address, pass it to
320 * The proxying router can't forward traffic sent to a link-local
321 * address, so signal the sender and discard the packet. This
322 * behavior is clarified by the MIPv6 specification.
324 if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
325 dst_link_failure(skb);
332 static inline int ip6_forward_finish(struct net *net, struct sock *sk,
335 return dst_output(net, sk, skb);
338 static unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst)
341 struct inet6_dev *idev;
343 if (dst_metric_locked(dst, RTAX_MTU)) {
344 mtu = dst_metric_raw(dst, RTAX_MTU);
351 idev = __in6_dev_get(dst->dev);
353 mtu = idev->cnf.mtu6;
359 static bool ip6_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
364 /* ipv6 conntrack defrag sets max_frag_size + ignore_df */
365 if (IP6CB(skb)->frag_max_size && IP6CB(skb)->frag_max_size > mtu)
371 if (skb_is_gso(skb) && skb_gso_network_seglen(skb) <= mtu)
377 int ip6_forward(struct sk_buff *skb)
379 struct dst_entry *dst = skb_dst(skb);
380 struct ipv6hdr *hdr = ipv6_hdr(skb);
381 struct inet6_skb_parm *opt = IP6CB(skb);
382 struct net *net = dev_net(dst->dev);
385 if (net->ipv6.devconf_all->forwarding == 0)
388 if (skb->pkt_type != PACKET_HOST)
391 if (unlikely(skb->sk))
394 if (skb_warn_if_lro(skb))
397 if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
398 __IP6_INC_STATS(net, ip6_dst_idev(dst),
399 IPSTATS_MIB_INDISCARDS);
403 skb_forward_csum(skb);
406 * We DO NOT make any processing on
407 * RA packets, pushing them to user level AS IS
408 * without ane WARRANTY that application will be able
409 * to interpret them. The reason is that we
410 * cannot make anything clever here.
412 * We are not end-node, so that if packet contains
413 * AH/ESP, we cannot make anything.
414 * Defragmentation also would be mistake, RA packets
415 * cannot be fragmented, because there is no warranty
416 * that different fragments will go along one path. --ANK
418 if (unlikely(opt->flags & IP6SKB_ROUTERALERT)) {
419 if (ip6_call_ra_chain(skb, ntohs(opt->ra)))
424 * check and decrement ttl
426 if (hdr->hop_limit <= 1) {
427 /* Force OUTPUT device used as source address */
429 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 0);
430 __IP6_INC_STATS(net, ip6_dst_idev(dst),
431 IPSTATS_MIB_INHDRERRORS);
437 /* XXX: idev->cnf.proxy_ndp? */
438 if (net->ipv6.devconf_all->proxy_ndp &&
439 pneigh_lookup(&nd_tbl, net, &hdr->daddr, skb->dev, 0)) {
440 int proxied = ip6_forward_proxy_check(skb);
442 return ip6_input(skb);
443 else if (proxied < 0) {
444 __IP6_INC_STATS(net, ip6_dst_idev(dst),
445 IPSTATS_MIB_INDISCARDS);
450 if (!xfrm6_route_forward(skb)) {
451 __IP6_INC_STATS(net, ip6_dst_idev(dst),
452 IPSTATS_MIB_INDISCARDS);
457 /* IPv6 specs say nothing about it, but it is clear that we cannot
458 send redirects to source routed frames.
459 We don't send redirects to frames decapsulated from IPsec.
461 if (skb->dev == dst->dev && opt->srcrt == 0 && !skb_sec_path(skb)) {
462 struct in6_addr *target = NULL;
463 struct inet_peer *peer;
467 * incoming and outgoing devices are the same
471 rt = (struct rt6_info *) dst;
472 if (rt->rt6i_flags & RTF_GATEWAY)
473 target = &rt->rt6i_gateway;
475 target = &hdr->daddr;
477 peer = inet_getpeer_v6(net->ipv6.peers, &hdr->daddr, 1);
479 /* Limit redirects both by destination (here)
480 and by source (inside ndisc_send_redirect)
482 if (inet_peer_xrlim_allow(peer, 1*HZ))
483 ndisc_send_redirect(skb, target);
487 int addrtype = ipv6_addr_type(&hdr->saddr);
489 /* This check is security critical. */
490 if (addrtype == IPV6_ADDR_ANY ||
491 addrtype & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LOOPBACK))
493 if (addrtype & IPV6_ADDR_LINKLOCAL) {
494 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
495 ICMPV6_NOT_NEIGHBOUR, 0);
500 mtu = ip6_dst_mtu_forward(dst);
501 if (mtu < IPV6_MIN_MTU)
504 if (ip6_pkt_too_big(skb, mtu)) {
505 /* Again, force OUTPUT device used as source address */
507 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
508 __IP6_INC_STATS(net, ip6_dst_idev(dst),
509 IPSTATS_MIB_INTOOBIGERRORS);
510 __IP6_INC_STATS(net, ip6_dst_idev(dst),
511 IPSTATS_MIB_FRAGFAILS);
516 if (skb_cow(skb, dst->dev->hard_header_len)) {
517 __IP6_INC_STATS(net, ip6_dst_idev(dst),
518 IPSTATS_MIB_OUTDISCARDS);
524 /* Mangling hops number delayed to point after skb COW */
528 __IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
529 __IP6_ADD_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTOCTETS, skb->len);
530 return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
531 net, NULL, skb, skb->dev, dst->dev,
535 __IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
541 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
543 to->pkt_type = from->pkt_type;
544 to->priority = from->priority;
545 to->protocol = from->protocol;
547 skb_dst_set(to, dst_clone(skb_dst(from)));
549 to->mark = from->mark;
551 #ifdef CONFIG_NET_SCHED
552 to->tc_index = from->tc_index;
555 skb_copy_secmark(to, from);
558 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
559 int (*output)(struct net *, struct sock *, struct sk_buff *))
561 struct sk_buff *frag;
562 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
563 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
564 inet6_sk(skb->sk) : NULL;
565 struct ipv6hdr *tmp_hdr;
567 unsigned int mtu, hlen, left, len;
570 int ptr, offset = 0, err = 0;
571 u8 *prevhdr, nexthdr = 0;
573 hlen = ip6_find_1stfragopt(skb, &prevhdr);
576 mtu = ip6_skb_dst_mtu(skb);
578 /* We must not fragment if the socket is set to force MTU discovery
579 * or if the skb it not generated by a local socket.
581 if (unlikely(!skb->ignore_df && skb->len > mtu))
584 if (IP6CB(skb)->frag_max_size) {
585 if (IP6CB(skb)->frag_max_size > mtu)
588 /* don't send fragments larger than what we received */
589 mtu = IP6CB(skb)->frag_max_size;
590 if (mtu < IPV6_MIN_MTU)
594 if (np && np->frag_size < mtu) {
598 if (mtu < hlen + sizeof(struct frag_hdr) + 8)
600 mtu -= hlen + sizeof(struct frag_hdr);
602 frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr,
603 &ipv6_hdr(skb)->saddr);
605 if (skb->ip_summed == CHECKSUM_PARTIAL &&
606 (err = skb_checksum_help(skb)))
609 hroom = LL_RESERVED_SPACE(rt->dst.dev);
610 if (skb_has_frag_list(skb)) {
611 int first_len = skb_pagelen(skb);
612 struct sk_buff *frag2;
614 if (first_len - hlen > mtu ||
615 ((first_len - hlen) & 7) ||
617 skb_headroom(skb) < (hroom + sizeof(struct frag_hdr)))
620 skb_walk_frags(skb, frag) {
621 /* Correct geometry. */
622 if (frag->len > mtu ||
623 ((frag->len & 7) && frag->next) ||
624 skb_headroom(frag) < (hlen + hroom + sizeof(struct frag_hdr)))
625 goto slow_path_clean;
627 /* Partially cloned skb? */
628 if (skb_shared(frag))
629 goto slow_path_clean;
634 frag->destructor = sock_wfree;
636 skb->truesize -= frag->truesize;
643 *prevhdr = NEXTHDR_FRAGMENT;
644 tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
646 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
647 IPSTATS_MIB_FRAGFAILS);
651 frag = skb_shinfo(skb)->frag_list;
652 skb_frag_list_init(skb);
654 __skb_pull(skb, hlen);
655 fh = (struct frag_hdr *)__skb_push(skb, sizeof(struct frag_hdr));
656 __skb_push(skb, hlen);
657 skb_reset_network_header(skb);
658 memcpy(skb_network_header(skb), tmp_hdr, hlen);
660 fh->nexthdr = nexthdr;
662 fh->frag_off = htons(IP6_MF);
663 fh->identification = frag_id;
665 first_len = skb_pagelen(skb);
666 skb->data_len = first_len - skb_headlen(skb);
667 skb->len = first_len;
668 ipv6_hdr(skb)->payload_len = htons(first_len -
669 sizeof(struct ipv6hdr));
674 /* Prepare header of the next frame,
675 * before previous one went down. */
677 frag->ip_summed = CHECKSUM_NONE;
678 skb_reset_transport_header(frag);
679 fh = (struct frag_hdr *)__skb_push(frag, sizeof(struct frag_hdr));
680 __skb_push(frag, hlen);
681 skb_reset_network_header(frag);
682 memcpy(skb_network_header(frag), tmp_hdr,
684 offset += skb->len - hlen - sizeof(struct frag_hdr);
685 fh->nexthdr = nexthdr;
687 fh->frag_off = htons(offset);
689 fh->frag_off |= htons(IP6_MF);
690 fh->identification = frag_id;
691 ipv6_hdr(frag)->payload_len =
693 sizeof(struct ipv6hdr));
694 ip6_copy_metadata(frag, skb);
697 err = output(net, sk, skb);
699 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
700 IPSTATS_MIB_FRAGCREATES);
713 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
714 IPSTATS_MIB_FRAGOKS);
719 kfree_skb_list(frag);
721 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
722 IPSTATS_MIB_FRAGFAILS);
727 skb_walk_frags(skb, frag2) {
731 frag2->destructor = NULL;
732 skb->truesize += frag2->truesize;
737 left = skb->len - hlen; /* Space per frame */
738 ptr = hlen; /* Where to start from */
741 * Fragment the datagram.
744 *prevhdr = NEXTHDR_FRAGMENT;
745 troom = rt->dst.dev->needed_tailroom;
748 * Keep copying data until we run out.
752 /* IF: it doesn't fit, use 'mtu' - the data space left */
755 /* IF: we are not sending up to and including the packet end
756 then align the next start on an eight byte boundary */
761 /* Allocate buffer */
762 frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
763 hroom + troom, GFP_ATOMIC);
765 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
766 IPSTATS_MIB_FRAGFAILS);
772 * Set up data on packet
775 ip6_copy_metadata(frag, skb);
776 skb_reserve(frag, hroom);
777 skb_put(frag, len + hlen + sizeof(struct frag_hdr));
778 skb_reset_network_header(frag);
779 fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
780 frag->transport_header = (frag->network_header + hlen +
781 sizeof(struct frag_hdr));
784 * Charge the memory for the fragment to any owner
788 skb_set_owner_w(frag, skb->sk);
791 * Copy the packet header into the new buffer.
793 skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
796 * Build fragment header.
798 fh->nexthdr = nexthdr;
800 fh->identification = frag_id;
803 * Copy a block of the IP datagram.
805 BUG_ON(skb_copy_bits(skb, ptr, skb_transport_header(frag),
809 fh->frag_off = htons(offset);
811 fh->frag_off |= htons(IP6_MF);
812 ipv6_hdr(frag)->payload_len = htons(frag->len -
813 sizeof(struct ipv6hdr));
819 * Put this fragment into the sending queue.
821 err = output(net, sk, frag);
825 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
826 IPSTATS_MIB_FRAGCREATES);
828 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
829 IPSTATS_MIB_FRAGOKS);
834 if (skb->sk && dst_allfrag(skb_dst(skb)))
835 sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);
837 skb->dev = skb_dst(skb)->dev;
838 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
842 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
843 IPSTATS_MIB_FRAGFAILS);
848 static inline int ip6_rt_check(const struct rt6key *rt_key,
849 const struct in6_addr *fl_addr,
850 const struct in6_addr *addr_cache)
852 return (rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
853 (!addr_cache || !ipv6_addr_equal(fl_addr, addr_cache));
856 static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
857 struct dst_entry *dst,
858 const struct flowi6 *fl6)
860 struct ipv6_pinfo *np = inet6_sk(sk);
866 if (dst->ops->family != AF_INET6) {
871 rt = (struct rt6_info *)dst;
872 /* Yes, checking route validity in not connected
873 * case is not very simple. Take into account,
874 * that we do not support routing by source, TOS,
875 * and MSG_DONTROUTE --ANK (980726)
877 * 1. ip6_rt_check(): If route was host route,
878 * check that cached destination is current.
879 * If it is network route, we still may
880 * check its validity using saved pointer
881 * to the last used address: daddr_cache.
882 * We do not want to save whole address now,
883 * (because main consumer of this service
884 * is tcp, which has not this problem),
885 * so that the last trick works only on connected
887 * 2. oif also should be the same.
889 if (ip6_rt_check(&rt->rt6i_dst, &fl6->daddr, np->daddr_cache) ||
890 #ifdef CONFIG_IPV6_SUBTREES
891 ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) ||
893 (!(fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF) &&
894 (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex))) {
903 static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
904 struct dst_entry **dst, struct flowi6 *fl6)
906 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
913 /* The correct way to handle this would be to do
914 * ip6_route_get_saddr, and then ip6_route_output; however,
915 * the route-specific preferred source forces the
916 * ip6_route_output call _before_ ip6_route_get_saddr.
918 * In source specific routing (no src=any default route),
919 * ip6_route_output will fail given src=any saddr, though, so
920 * that's why we try it again later.
922 if (ipv6_addr_any(&fl6->saddr) && (!*dst || !(*dst)->error)) {
924 bool had_dst = *dst != NULL;
927 *dst = ip6_route_output(net, sk, fl6);
928 rt = (*dst)->error ? NULL : (struct rt6_info *)*dst;
929 err = ip6_route_get_saddr(net, rt, &fl6->daddr,
930 sk ? inet6_sk(sk)->srcprefs : 0,
933 goto out_err_release;
935 /* If we had an erroneous initial result, pretend it
936 * never existed and let the SA-enabled version take
939 if (!had_dst && (*dst)->error) {
945 flags |= RT6_LOOKUP_F_IFACE;
949 *dst = ip6_route_output_flags(net, sk, fl6, flags);
953 goto out_err_release;
955 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
957 * Here if the dst entry we've looked up
958 * has a neighbour entry that is in the INCOMPLETE
959 * state and the src address from the flow is
960 * marked as OPTIMISTIC, we release the found
961 * dst entry and replace it instead with the
962 * dst entry of the nexthop router
964 rt = (struct rt6_info *) *dst;
966 n = __ipv6_neigh_lookup_noref(rt->dst.dev,
967 rt6_nexthop(rt, &fl6->daddr));
968 err = n && !(n->nud_state & NUD_VALID) ? -EINVAL : 0;
969 rcu_read_unlock_bh();
972 struct inet6_ifaddr *ifp;
973 struct flowi6 fl_gw6;
976 ifp = ipv6_get_ifaddr(net, &fl6->saddr,
979 redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
985 * We need to get the dst entry for the
986 * default router instead
989 memcpy(&fl_gw6, fl6, sizeof(struct flowi6));
990 memset(&fl_gw6.daddr, 0, sizeof(struct in6_addr));
991 *dst = ip6_route_output(net, sk, &fl_gw6);
994 goto out_err_release;
1002 if (err == -ENETUNREACH)
1003 IP6_INC_STATS(net, NULL, IPSTATS_MIB_OUTNOROUTES);
1010 * ip6_dst_lookup - perform route lookup on flow
1011 * @sk: socket which provides route info
1012 * @dst: pointer to dst_entry * for result
1013 * @fl6: flow to lookup
1015 * This function performs a route lookup on the given flow.
1017 * It returns zero on success, or a standard errno code on error.
1019 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1023 return ip6_dst_lookup_tail(net, sk, dst, fl6);
1025 EXPORT_SYMBOL_GPL(ip6_dst_lookup);
1028 * ip6_dst_lookup_flow - perform route lookup on flow with ipsec
1029 * @sk: socket which provides route info
1030 * @fl6: flow to lookup
1031 * @final_dst: final destination address for ipsec lookup
1033 * This function performs a route lookup on the given flow.
1035 * It returns a valid dst pointer on success, or a pointer encoded
1038 struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
1039 const struct in6_addr *final_dst)
1041 struct dst_entry *dst = NULL;
1044 err = ip6_dst_lookup_tail(sock_net(sk), sk, &dst, fl6);
1046 return ERR_PTR(err);
1048 fl6->daddr = *final_dst;
1049 if (!fl6->flowi6_oif)
1050 fl6->flowi6_oif = l3mdev_fib_oif(dst->dev);
1052 return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
1054 EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow);
1057 * ip6_sk_dst_lookup_flow - perform socket cached route lookup on flow
1058 * @sk: socket which provides the dst cache and route info
1059 * @fl6: flow to lookup
1060 * @final_dst: final destination address for ipsec lookup
1062 * This function performs a route lookup on the given flow with the
1063 * possibility of using the cached route in the socket if it is valid.
1064 * It will take the socket dst lock when operating on the dst cache.
1065 * As a result, this function can only be used in process context.
1067 * It returns a valid dst pointer on success, or a pointer encoded
1070 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1071 const struct in6_addr *final_dst)
1073 struct dst_entry *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
1075 dst = ip6_sk_dst_check(sk, dst, fl6);
1077 dst = ip6_dst_lookup_flow(sk, fl6, final_dst);
1081 EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup_flow);
1083 static inline int ip6_ufo_append_data(struct sock *sk,
1084 struct sk_buff_head *queue,
1085 int getfrag(void *from, char *to, int offset, int len,
1086 int odd, struct sk_buff *skb),
1087 void *from, int length, int hh_len, int fragheaderlen,
1088 int exthdrlen, int transhdrlen, int mtu,
1089 unsigned int flags, const struct flowi6 *fl6)
1092 struct sk_buff *skb;
1095 /* There is support for UDP large send offload by network
1096 * device, so create one single skb packet containing complete
1099 skb = skb_peek_tail(queue);
1101 skb = sock_alloc_send_skb(sk,
1102 hh_len + fragheaderlen + transhdrlen + 20,
1103 (flags & MSG_DONTWAIT), &err);
1107 /* reserve space for Hardware header */
1108 skb_reserve(skb, hh_len);
1110 /* create space for UDP/IP header */
1111 skb_put(skb, fragheaderlen + transhdrlen);
1113 /* initialize network header pointer */
1114 skb_set_network_header(skb, exthdrlen);
1116 /* initialize protocol header pointer */
1117 skb->transport_header = skb->network_header + fragheaderlen;
1119 skb->protocol = htons(ETH_P_IPV6);
1122 __skb_queue_tail(queue, skb);
1123 } else if (skb_is_gso(skb)) {
1127 skb->ip_summed = CHECKSUM_PARTIAL;
1128 /* Specify the length of each IPv6 datagram fragment.
1129 * It has to be a multiple of 8.
1131 skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
1132 sizeof(struct frag_hdr)) & ~7;
1133 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
1134 skb_shinfo(skb)->ip6_frag_id = ipv6_select_ident(sock_net(sk),
1139 return skb_append_datato_frags(sk, skb, getfrag, from,
1140 (length - transhdrlen));
1143 static inline struct ipv6_opt_hdr *ip6_opt_dup(struct ipv6_opt_hdr *src,
1146 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1149 static inline struct ipv6_rt_hdr *ip6_rthdr_dup(struct ipv6_rt_hdr *src,
1152 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1155 static void ip6_append_data_mtu(unsigned int *mtu,
1157 unsigned int fragheaderlen,
1158 struct sk_buff *skb,
1159 struct rt6_info *rt,
1160 unsigned int orig_mtu)
1162 if (!(rt->dst.flags & DST_XFRM_TUNNEL)) {
1164 /* first fragment, reserve header_len */
1165 *mtu = orig_mtu - rt->dst.header_len;
1169 * this fragment is not first, the headers
1170 * space is regarded as data space.
1174 *maxfraglen = ((*mtu - fragheaderlen) & ~7)
1175 + fragheaderlen - sizeof(struct frag_hdr);
1179 static int ip6_setup_cork(struct sock *sk, struct inet_cork_full *cork,
1180 struct inet6_cork *v6_cork, struct ipcm6_cookie *ipc6,
1181 struct rt6_info *rt, struct flowi6 *fl6)
1183 struct ipv6_pinfo *np = inet6_sk(sk);
1185 struct ipv6_txoptions *opt = ipc6->opt;
1191 if (WARN_ON(v6_cork->opt))
1194 v6_cork->opt = kzalloc(opt->tot_len, sk->sk_allocation);
1195 if (unlikely(!v6_cork->opt))
1198 v6_cork->opt->tot_len = opt->tot_len;
1199 v6_cork->opt->opt_flen = opt->opt_flen;
1200 v6_cork->opt->opt_nflen = opt->opt_nflen;
1202 v6_cork->opt->dst0opt = ip6_opt_dup(opt->dst0opt,
1204 if (opt->dst0opt && !v6_cork->opt->dst0opt)
1207 v6_cork->opt->dst1opt = ip6_opt_dup(opt->dst1opt,
1209 if (opt->dst1opt && !v6_cork->opt->dst1opt)
1212 v6_cork->opt->hopopt = ip6_opt_dup(opt->hopopt,
1214 if (opt->hopopt && !v6_cork->opt->hopopt)
1217 v6_cork->opt->srcrt = ip6_rthdr_dup(opt->srcrt,
1219 if (opt->srcrt && !v6_cork->opt->srcrt)
1222 /* need source address above miyazawa*/
1225 cork->base.dst = &rt->dst;
1226 cork->fl.u.ip6 = *fl6;
1227 v6_cork->hop_limit = ipc6->hlimit;
1228 v6_cork->tclass = ipc6->tclass;
1229 if (rt->dst.flags & DST_XFRM_TUNNEL)
1230 mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ?
1231 rt->dst.dev->mtu : dst_mtu(&rt->dst);
1233 mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ?
1234 rt->dst.dev->mtu : dst_mtu(rt->dst.path);
1235 if (np->frag_size < mtu) {
1237 mtu = np->frag_size;
1239 cork->base.fragsize = mtu;
1240 if (dst_allfrag(rt->dst.path))
1241 cork->base.flags |= IPCORK_ALLFRAG;
1242 cork->base.length = 0;
1247 static int __ip6_append_data(struct sock *sk,
1249 struct sk_buff_head *queue,
1250 struct inet_cork *cork,
1251 struct inet6_cork *v6_cork,
1252 struct page_frag *pfrag,
1253 int getfrag(void *from, char *to, int offset,
1254 int len, int odd, struct sk_buff *skb),
1255 void *from, int length, int transhdrlen,
1256 unsigned int flags, struct ipcm6_cookie *ipc6,
1257 const struct sockcm_cookie *sockc)
1259 struct sk_buff *skb, *skb_prev = NULL;
1260 unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu;
1262 int dst_exthdrlen = 0;
1269 struct rt6_info *rt = (struct rt6_info *)cork->dst;
1270 struct ipv6_txoptions *opt = v6_cork->opt;
1271 int csummode = CHECKSUM_NONE;
1272 unsigned int maxnonfragsize, headersize;
1274 skb = skb_peek_tail(queue);
1276 exthdrlen = opt ? opt->opt_flen : 0;
1277 dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len;
1280 mtu = cork->fragsize;
1283 hh_len = LL_RESERVED_SPACE(rt->dst.dev);
1285 fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len +
1286 (opt ? opt->opt_nflen : 0);
1287 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen -
1288 sizeof(struct frag_hdr);
1290 headersize = sizeof(struct ipv6hdr) +
1291 (opt ? opt->opt_flen + opt->opt_nflen : 0) +
1292 (dst_allfrag(&rt->dst) ?
1293 sizeof(struct frag_hdr) : 0) +
1294 rt->rt6i_nfheader_len;
1296 if (cork->length + length > mtu - headersize && ipc6->dontfrag &&
1297 (sk->sk_protocol == IPPROTO_UDP ||
1298 sk->sk_protocol == IPPROTO_RAW)) {
1299 ipv6_local_rxpmtu(sk, fl6, mtu - headersize +
1300 sizeof(struct ipv6hdr));
1304 if (ip6_sk_ignore_df(sk))
1305 maxnonfragsize = sizeof(struct ipv6hdr) + IPV6_MAXPLEN;
1307 maxnonfragsize = mtu;
1309 if (cork->length + length > maxnonfragsize - headersize) {
1311 ipv6_local_error(sk, EMSGSIZE, fl6,
1313 sizeof(struct ipv6hdr));
1317 /* CHECKSUM_PARTIAL only with no extension headers and when
1318 * we are not going to fragment
1320 if (transhdrlen && sk->sk_protocol == IPPROTO_UDP &&
1321 headersize == sizeof(struct ipv6hdr) &&
1322 length < mtu - headersize &&
1323 !(flags & MSG_MORE) &&
1324 rt->dst.dev->features & (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))
1325 csummode = CHECKSUM_PARTIAL;
1327 if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) {
1328 sock_tx_timestamp(sk, sockc->tsflags, &tx_flags);
1329 if (tx_flags & SKBTX_ANY_SW_TSTAMP &&
1330 sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
1331 tskey = sk->sk_tskey++;
1335 * Let's try using as much space as possible.
1336 * Use MTU if total length of the message fits into the MTU.
1337 * Otherwise, we need to reserve fragment header and
1338 * fragment alignment (= 8-15 octects, in total).
1340 * Note that we may need to "move" the data from the tail of
1341 * of the buffer to the new fragment when we split
1344 * FIXME: It may be fragmented into multiple chunks
1345 * at once if non-fragmentable extension headers
1350 cork->length += length;
1351 if (((length > mtu) ||
1352 (skb && skb_is_gso(skb))) &&
1353 (sk->sk_protocol == IPPROTO_UDP) &&
1354 (rt->dst.dev->features & NETIF_F_UFO) &&
1355 (sk->sk_type == SOCK_DGRAM) && !udp_get_no_check6_tx(sk)) {
1356 err = ip6_ufo_append_data(sk, queue, getfrag, from, length,
1357 hh_len, fragheaderlen, exthdrlen,
1358 transhdrlen, mtu, flags, fl6);
1367 while (length > 0) {
1368 /* Check if the remaining data fits into current packet. */
1369 copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
1371 copy = maxfraglen - skb->len;
1375 unsigned int datalen;
1376 unsigned int fraglen;
1377 unsigned int fraggap;
1378 unsigned int alloclen;
1380 /* There's no room in the current skb */
1382 fraggap = skb->len - maxfraglen;
1385 /* update mtu and maxfraglen if necessary */
1386 if (!skb || !skb_prev)
1387 ip6_append_data_mtu(&mtu, &maxfraglen,
1388 fragheaderlen, skb, rt,
1394 * If remaining data exceeds the mtu,
1395 * we know we need more fragment(s).
1397 datalen = length + fraggap;
1399 if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
1400 datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len;
1401 if ((flags & MSG_MORE) &&
1402 !(rt->dst.dev->features&NETIF_F_SG))
1405 alloclen = datalen + fragheaderlen;
1407 alloclen += dst_exthdrlen;
1409 if (datalen != length + fraggap) {
1411 * this is not the last fragment, the trailer
1412 * space is regarded as data space.
1414 datalen += rt->dst.trailer_len;
1417 alloclen += rt->dst.trailer_len;
1418 fraglen = datalen + fragheaderlen;
1421 * We just reserve space for fragment header.
1422 * Note: this may be overallocation if the message
1423 * (without MSG_MORE) fits into the MTU.
1425 alloclen += sizeof(struct frag_hdr);
1428 skb = sock_alloc_send_skb(sk,
1430 (flags & MSG_DONTWAIT), &err);
1433 if (atomic_read(&sk->sk_wmem_alloc) <=
1435 skb = sock_wmalloc(sk,
1436 alloclen + hh_len, 1,
1444 * Fill in the control structures
1446 skb->protocol = htons(ETH_P_IPV6);
1447 skb->ip_summed = csummode;
1449 /* reserve for fragmentation and ipsec header */
1450 skb_reserve(skb, hh_len + sizeof(struct frag_hdr) +
1453 /* Only the initial fragment is time stamped */
1454 skb_shinfo(skb)->tx_flags = tx_flags;
1456 skb_shinfo(skb)->tskey = tskey;
1460 * Find where to start putting bytes
1462 data = skb_put(skb, fraglen);
1463 skb_set_network_header(skb, exthdrlen);
1464 data += fragheaderlen;
1465 skb->transport_header = (skb->network_header +
1468 skb->csum = skb_copy_and_csum_bits(
1469 skb_prev, maxfraglen,
1470 data + transhdrlen, fraggap, 0);
1471 skb_prev->csum = csum_sub(skb_prev->csum,
1474 pskb_trim_unique(skb_prev, maxfraglen);
1476 copy = datalen - transhdrlen - fraggap;
1482 } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
1489 length -= datalen - fraggap;
1495 * Put the packet on the pending queue
1497 __skb_queue_tail(queue, skb);
1504 if (!(rt->dst.dev->features&NETIF_F_SG)) {
1508 if (getfrag(from, skb_put(skb, copy),
1509 offset, copy, off, skb) < 0) {
1510 __skb_trim(skb, off);
1515 int i = skb_shinfo(skb)->nr_frags;
1518 if (!sk_page_frag_refill(sk, pfrag))
1521 if (!skb_can_coalesce(skb, i, pfrag->page,
1524 if (i == MAX_SKB_FRAGS)
1527 __skb_fill_page_desc(skb, i, pfrag->page,
1529 skb_shinfo(skb)->nr_frags = ++i;
1530 get_page(pfrag->page);
1532 copy = min_t(int, copy, pfrag->size - pfrag->offset);
1534 page_address(pfrag->page) + pfrag->offset,
1535 offset, copy, skb->len, skb) < 0)
1538 pfrag->offset += copy;
1539 skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
1541 skb->data_len += copy;
1542 skb->truesize += copy;
1543 atomic_add(copy, &sk->sk_wmem_alloc);
1554 cork->length -= length;
1555 IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
1559 int ip6_append_data(struct sock *sk,
1560 int getfrag(void *from, char *to, int offset, int len,
1561 int odd, struct sk_buff *skb),
1562 void *from, int length, int transhdrlen,
1563 struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1564 struct rt6_info *rt, unsigned int flags,
1565 const struct sockcm_cookie *sockc)
1567 struct inet_sock *inet = inet_sk(sk);
1568 struct ipv6_pinfo *np = inet6_sk(sk);
1572 if (flags&MSG_PROBE)
1574 if (skb_queue_empty(&sk->sk_write_queue)) {
1578 err = ip6_setup_cork(sk, &inet->cork, &np->cork,
1583 exthdrlen = (ipc6->opt ? ipc6->opt->opt_flen : 0);
1584 length += exthdrlen;
1585 transhdrlen += exthdrlen;
1587 fl6 = &inet->cork.fl.u.ip6;
1591 return __ip6_append_data(sk, fl6, &sk->sk_write_queue, &inet->cork.base,
1592 &np->cork, sk_page_frag(sk), getfrag,
1593 from, length, transhdrlen, flags, ipc6, sockc);
1595 EXPORT_SYMBOL_GPL(ip6_append_data);
1597 static void ip6_cork_release(struct inet_cork_full *cork,
1598 struct inet6_cork *v6_cork)
1601 kfree(v6_cork->opt->dst0opt);
1602 kfree(v6_cork->opt->dst1opt);
1603 kfree(v6_cork->opt->hopopt);
1604 kfree(v6_cork->opt->srcrt);
1605 kfree(v6_cork->opt);
1606 v6_cork->opt = NULL;
1609 if (cork->base.dst) {
1610 dst_release(cork->base.dst);
1611 cork->base.dst = NULL;
1612 cork->base.flags &= ~IPCORK_ALLFRAG;
1614 memset(&cork->fl, 0, sizeof(cork->fl));
1617 struct sk_buff *__ip6_make_skb(struct sock *sk,
1618 struct sk_buff_head *queue,
1619 struct inet_cork_full *cork,
1620 struct inet6_cork *v6_cork)
1622 struct sk_buff *skb, *tmp_skb;
1623 struct sk_buff **tail_skb;
1624 struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
1625 struct ipv6_pinfo *np = inet6_sk(sk);
1626 struct net *net = sock_net(sk);
1627 struct ipv6hdr *hdr;
1628 struct ipv6_txoptions *opt = v6_cork->opt;
1629 struct rt6_info *rt = (struct rt6_info *)cork->base.dst;
1630 struct flowi6 *fl6 = &cork->fl.u.ip6;
1631 unsigned char proto = fl6->flowi6_proto;
1633 skb = __skb_dequeue(queue);
1636 tail_skb = &(skb_shinfo(skb)->frag_list);
1638 /* move skb->data to ip header from ext header */
1639 if (skb->data < skb_network_header(skb))
1640 __skb_pull(skb, skb_network_offset(skb));
1641 while ((tmp_skb = __skb_dequeue(queue)) != NULL) {
1642 __skb_pull(tmp_skb, skb_network_header_len(skb));
1643 *tail_skb = tmp_skb;
1644 tail_skb = &(tmp_skb->next);
1645 skb->len += tmp_skb->len;
1646 skb->data_len += tmp_skb->len;
1647 skb->truesize += tmp_skb->truesize;
1648 tmp_skb->destructor = NULL;
1652 /* Allow local fragmentation. */
1653 skb->ignore_df = ip6_sk_ignore_df(sk);
1655 *final_dst = fl6->daddr;
1656 __skb_pull(skb, skb_network_header_len(skb));
1657 if (opt && opt->opt_flen)
1658 ipv6_push_frag_opts(skb, opt, &proto);
1659 if (opt && opt->opt_nflen)
1660 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
1662 skb_push(skb, sizeof(struct ipv6hdr));
1663 skb_reset_network_header(skb);
1664 hdr = ipv6_hdr(skb);
1666 ip6_flow_hdr(hdr, v6_cork->tclass,
1667 ip6_make_flowlabel(net, skb, fl6->flowlabel,
1668 np->autoflowlabel, fl6));
1669 hdr->hop_limit = v6_cork->hop_limit;
1670 hdr->nexthdr = proto;
1671 hdr->saddr = fl6->saddr;
1672 hdr->daddr = *final_dst;
1674 skb->priority = sk->sk_priority;
1675 skb->mark = sk->sk_mark;
1677 skb_dst_set(skb, dst_clone(&rt->dst));
1678 IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len);
1679 if (proto == IPPROTO_ICMPV6) {
1680 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
1682 ICMP6MSGOUT_INC_STATS(net, idev, icmp6_hdr(skb)->icmp6_type);
1683 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1686 ip6_cork_release(cork, v6_cork);
1691 int ip6_send_skb(struct sk_buff *skb)
1693 struct net *net = sock_net(skb->sk);
1694 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
1697 err = ip6_local_out(net, skb->sk, skb);
1700 err = net_xmit_errno(err);
1702 IP6_INC_STATS(net, rt->rt6i_idev,
1703 IPSTATS_MIB_OUTDISCARDS);
1709 int ip6_push_pending_frames(struct sock *sk)
1711 struct sk_buff *skb;
1713 skb = ip6_finish_skb(sk);
1717 return ip6_send_skb(skb);
1719 EXPORT_SYMBOL_GPL(ip6_push_pending_frames);
1721 static void __ip6_flush_pending_frames(struct sock *sk,
1722 struct sk_buff_head *queue,
1723 struct inet_cork_full *cork,
1724 struct inet6_cork *v6_cork)
1726 struct sk_buff *skb;
1728 while ((skb = __skb_dequeue_tail(queue)) != NULL) {
1730 IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb_dst(skb)),
1731 IPSTATS_MIB_OUTDISCARDS);
1735 ip6_cork_release(cork, v6_cork);
1738 void ip6_flush_pending_frames(struct sock *sk)
1740 __ip6_flush_pending_frames(sk, &sk->sk_write_queue,
1741 &inet_sk(sk)->cork, &inet6_sk(sk)->cork);
1743 EXPORT_SYMBOL_GPL(ip6_flush_pending_frames);
1745 struct sk_buff *ip6_make_skb(struct sock *sk,
1746 int getfrag(void *from, char *to, int offset,
1747 int len, int odd, struct sk_buff *skb),
1748 void *from, int length, int transhdrlen,
1749 struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1750 struct rt6_info *rt, unsigned int flags,
1751 const struct sockcm_cookie *sockc)
1753 struct inet_cork_full cork;
1754 struct inet6_cork v6_cork;
1755 struct sk_buff_head queue;
1756 int exthdrlen = (ipc6->opt ? ipc6->opt->opt_flen : 0);
1759 if (flags & MSG_PROBE)
1762 __skb_queue_head_init(&queue);
1764 cork.base.flags = 0;
1766 cork.base.opt = NULL;
1768 err = ip6_setup_cork(sk, &cork, &v6_cork, ipc6, rt, fl6);
1770 return ERR_PTR(err);
1772 if (ipc6->dontfrag < 0)
1773 ipc6->dontfrag = inet6_sk(sk)->dontfrag;
1775 err = __ip6_append_data(sk, fl6, &queue, &cork.base, &v6_cork,
1776 ¤t->task_frag, getfrag, from,
1777 length + exthdrlen, transhdrlen + exthdrlen,
1778 flags, ipc6, sockc);
1780 __ip6_flush_pending_frames(sk, &queue, &cork, &v6_cork);
1781 return ERR_PTR(err);
1784 return __ip6_make_skb(sk, &queue, &cork, &v6_cork);