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/bpf-cgroup.h>
43 #include <linux/netfilter.h>
44 #include <linux/netfilter_ipv6.h>
50 #include <net/ndisc.h>
51 #include <net/protocol.h>
52 #include <net/ip6_route.h>
53 #include <net/addrconf.h>
54 #include <net/rawv6.h>
57 #include <net/checksum.h>
58 #include <linux/mroute6.h>
59 #include <net/l3mdev.h>
60 #include <net/lwtunnel.h>
62 static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb)
64 struct dst_entry *dst = skb_dst(skb);
65 struct net_device *dev = dst->dev;
66 struct neighbour *neigh;
67 struct in6_addr *nexthop;
70 skb->protocol = htons(ETH_P_IPV6);
73 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
74 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
76 if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(sk) &&
77 ((mroute6_socket(net, skb) &&
78 !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||
79 ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
80 &ipv6_hdr(skb)->saddr))) {
81 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
83 /* Do not check for IFF_ALLMULTI; multicast routing
84 is not supported in any case.
87 NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING,
88 net, sk, newskb, NULL, newskb->dev,
91 if (ipv6_hdr(skb)->hop_limit == 0) {
92 IP6_INC_STATS(net, idev,
93 IPSTATS_MIB_OUTDISCARDS);
99 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, skb->len);
101 if (IPV6_ADDR_MC_SCOPE(&ipv6_hdr(skb)->daddr) <=
102 IPV6_ADDR_SCOPE_NODELOCAL &&
103 !(dev->flags & IFF_LOOPBACK)) {
109 if (lwtunnel_xmit_redirect(dst->lwtstate)) {
110 int res = lwtunnel_xmit(skb);
112 if (res < 0 || res == LWTUNNEL_XMIT_DONE)
117 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
118 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
119 if (unlikely(!neigh))
120 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
121 if (!IS_ERR(neigh)) {
122 ret = dst_neigh_output(dst, neigh, skb);
123 rcu_read_unlock_bh();
126 rcu_read_unlock_bh();
128 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
133 static int ip6_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
137 ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb);
143 if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
144 dst_allfrag(skb_dst(skb)) ||
145 (IP6CB(skb)->frag_max_size && skb->len > IP6CB(skb)->frag_max_size))
146 return ip6_fragment(net, sk, skb, ip6_finish_output2);
148 return ip6_finish_output2(net, sk, skb);
151 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
153 struct net_device *dev = skb_dst(skb)->dev;
154 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
156 if (unlikely(idev->cnf.disable_ipv6)) {
157 IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
162 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
163 net, sk, skb, NULL, dev,
165 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
169 * xmit an sk_buff (used by TCP, SCTP and DCCP)
170 * Note : socket lock is not held for SYNACK packets, but might be modified
171 * by calls to skb_set_owner_w() and ipv6_local_error(),
172 * which are using proper atomic operations or spinlocks.
174 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
175 __u32 mark, struct ipv6_txoptions *opt, int tclass)
177 struct net *net = sock_net(sk);
178 const struct ipv6_pinfo *np = inet6_sk(sk);
179 struct in6_addr *first_hop = &fl6->daddr;
180 struct dst_entry *dst = skb_dst(skb);
182 u8 proto = fl6->flowi6_proto;
183 int seg_len = skb->len;
188 unsigned int head_room;
190 /* First: exthdrs may take lots of space (~8K for now)
191 MAX_HEADER is not enough.
193 head_room = opt->opt_nflen + opt->opt_flen;
194 seg_len += head_room;
195 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
197 if (skb_headroom(skb) < head_room) {
198 struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
200 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
201 IPSTATS_MIB_OUTDISCARDS);
207 /* skb_set_owner_w() changes sk->sk_wmem_alloc atomically,
208 * it is safe to call in our context (socket lock not held)
210 skb_set_owner_w(skb, (struct sock *)sk);
213 ipv6_push_frag_opts(skb, opt, &proto);
215 ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop,
219 skb_push(skb, sizeof(struct ipv6hdr));
220 skb_reset_network_header(skb);
224 * Fill in the IPv6 header
227 hlimit = np->hop_limit;
229 hlimit = ip6_dst_hoplimit(dst);
231 ip6_flow_hdr(hdr, tclass, ip6_make_flowlabel(net, skb, fl6->flowlabel,
232 np->autoflowlabel, fl6));
234 hdr->payload_len = htons(seg_len);
235 hdr->nexthdr = proto;
236 hdr->hop_limit = hlimit;
238 hdr->saddr = fl6->saddr;
239 hdr->daddr = *first_hop;
241 skb->protocol = htons(ETH_P_IPV6);
242 skb->priority = sk->sk_priority;
246 if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) {
247 IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
248 IPSTATS_MIB_OUT, skb->len);
250 /* if egress device is enslaved to an L3 master device pass the
251 * skb to its handler for processing
253 skb = l3mdev_ip6_out((struct sock *)sk, skb);
257 /* hooks should never assume socket lock is held.
258 * we promote our socket to non const
260 return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
261 net, (struct sock *)sk, skb, NULL, dst->dev,
266 /* ipv6_local_error() does not require socket lock,
267 * we promote our socket to non const
269 ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu);
271 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
275 EXPORT_SYMBOL(ip6_xmit);
277 static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
279 struct ip6_ra_chain *ra;
280 struct sock *last = NULL;
282 read_lock(&ip6_ra_lock);
283 for (ra = ip6_ra_chain; ra; ra = ra->next) {
284 struct sock *sk = ra->sk;
285 if (sk && ra->sel == sel &&
286 (!sk->sk_bound_dev_if ||
287 sk->sk_bound_dev_if == skb->dev->ifindex)) {
289 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
291 rawv6_rcv(last, skb2);
298 rawv6_rcv(last, skb);
299 read_unlock(&ip6_ra_lock);
302 read_unlock(&ip6_ra_lock);
306 static int ip6_forward_proxy_check(struct sk_buff *skb)
308 struct ipv6hdr *hdr = ipv6_hdr(skb);
309 u8 nexthdr = hdr->nexthdr;
313 if (ipv6_ext_hdr(nexthdr)) {
314 offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr, &frag_off);
318 offset = sizeof(struct ipv6hdr);
320 if (nexthdr == IPPROTO_ICMPV6) {
321 struct icmp6hdr *icmp6;
323 if (!pskb_may_pull(skb, (skb_network_header(skb) +
324 offset + 1 - skb->data)))
327 icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
329 switch (icmp6->icmp6_type) {
330 case NDISC_ROUTER_SOLICITATION:
331 case NDISC_ROUTER_ADVERTISEMENT:
332 case NDISC_NEIGHBOUR_SOLICITATION:
333 case NDISC_NEIGHBOUR_ADVERTISEMENT:
335 /* For reaction involving unicast neighbor discovery
336 * message destined to the proxied address, pass it to
346 * The proxying router can't forward traffic sent to a link-local
347 * address, so signal the sender and discard the packet. This
348 * behavior is clarified by the MIPv6 specification.
350 if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
351 dst_link_failure(skb);
358 static inline int ip6_forward_finish(struct net *net, struct sock *sk,
361 return dst_output(net, sk, skb);
364 static unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst)
367 struct inet6_dev *idev;
369 if (dst_metric_locked(dst, RTAX_MTU)) {
370 mtu = dst_metric_raw(dst, RTAX_MTU);
377 idev = __in6_dev_get(dst->dev);
379 mtu = idev->cnf.mtu6;
385 static bool ip6_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
390 /* ipv6 conntrack defrag sets max_frag_size + ignore_df */
391 if (IP6CB(skb)->frag_max_size && IP6CB(skb)->frag_max_size > mtu)
397 if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))
403 int ip6_forward(struct sk_buff *skb)
405 struct dst_entry *dst = skb_dst(skb);
406 struct ipv6hdr *hdr = ipv6_hdr(skb);
407 struct inet6_skb_parm *opt = IP6CB(skb);
408 struct net *net = dev_net(dst->dev);
411 if (net->ipv6.devconf_all->forwarding == 0)
414 if (skb->pkt_type != PACKET_HOST)
417 if (unlikely(skb->sk))
420 if (skb_warn_if_lro(skb))
423 if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
424 __IP6_INC_STATS(net, ip6_dst_idev(dst),
425 IPSTATS_MIB_INDISCARDS);
429 skb_forward_csum(skb);
432 * We DO NOT make any processing on
433 * RA packets, pushing them to user level AS IS
434 * without ane WARRANTY that application will be able
435 * to interpret them. The reason is that we
436 * cannot make anything clever here.
438 * We are not end-node, so that if packet contains
439 * AH/ESP, we cannot make anything.
440 * Defragmentation also would be mistake, RA packets
441 * cannot be fragmented, because there is no warranty
442 * that different fragments will go along one path. --ANK
444 if (unlikely(opt->flags & IP6SKB_ROUTERALERT)) {
445 if (ip6_call_ra_chain(skb, ntohs(opt->ra)))
450 * check and decrement ttl
452 if (hdr->hop_limit <= 1) {
453 /* Force OUTPUT device used as source address */
455 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 0);
456 __IP6_INC_STATS(net, ip6_dst_idev(dst),
457 IPSTATS_MIB_INHDRERRORS);
463 /* XXX: idev->cnf.proxy_ndp? */
464 if (net->ipv6.devconf_all->proxy_ndp &&
465 pneigh_lookup(&nd_tbl, net, &hdr->daddr, skb->dev, 0)) {
466 int proxied = ip6_forward_proxy_check(skb);
468 return ip6_input(skb);
469 else if (proxied < 0) {
470 __IP6_INC_STATS(net, ip6_dst_idev(dst),
471 IPSTATS_MIB_INDISCARDS);
476 if (!xfrm6_route_forward(skb)) {
477 __IP6_INC_STATS(net, ip6_dst_idev(dst),
478 IPSTATS_MIB_INDISCARDS);
483 /* IPv6 specs say nothing about it, but it is clear that we cannot
484 send redirects to source routed frames.
485 We don't send redirects to frames decapsulated from IPsec.
487 if (skb->dev == dst->dev && opt->srcrt == 0 && !skb_sec_path(skb)) {
488 struct in6_addr *target = NULL;
489 struct inet_peer *peer;
493 * incoming and outgoing devices are the same
497 rt = (struct rt6_info *) dst;
498 if (rt->rt6i_flags & RTF_GATEWAY)
499 target = &rt->rt6i_gateway;
501 target = &hdr->daddr;
503 peer = inet_getpeer_v6(net->ipv6.peers, &hdr->daddr, 1);
505 /* Limit redirects both by destination (here)
506 and by source (inside ndisc_send_redirect)
508 if (inet_peer_xrlim_allow(peer, 1*HZ))
509 ndisc_send_redirect(skb, target);
513 int addrtype = ipv6_addr_type(&hdr->saddr);
515 /* This check is security critical. */
516 if (addrtype == IPV6_ADDR_ANY ||
517 addrtype & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LOOPBACK))
519 if (addrtype & IPV6_ADDR_LINKLOCAL) {
520 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
521 ICMPV6_NOT_NEIGHBOUR, 0);
526 mtu = ip6_dst_mtu_forward(dst);
527 if (mtu < IPV6_MIN_MTU)
530 if (ip6_pkt_too_big(skb, mtu)) {
531 /* Again, force OUTPUT device used as source address */
533 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
534 __IP6_INC_STATS(net, ip6_dst_idev(dst),
535 IPSTATS_MIB_INTOOBIGERRORS);
536 __IP6_INC_STATS(net, ip6_dst_idev(dst),
537 IPSTATS_MIB_FRAGFAILS);
542 if (skb_cow(skb, dst->dev->hard_header_len)) {
543 __IP6_INC_STATS(net, ip6_dst_idev(dst),
544 IPSTATS_MIB_OUTDISCARDS);
550 /* Mangling hops number delayed to point after skb COW */
554 __IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
555 __IP6_ADD_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTOCTETS, skb->len);
556 return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
557 net, NULL, skb, skb->dev, dst->dev,
561 __IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
567 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
569 to->pkt_type = from->pkt_type;
570 to->priority = from->priority;
571 to->protocol = from->protocol;
573 skb_dst_set(to, dst_clone(skb_dst(from)));
575 to->mark = from->mark;
577 #ifdef CONFIG_NET_SCHED
578 to->tc_index = from->tc_index;
581 skb_copy_secmark(to, from);
584 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
585 int (*output)(struct net *, struct sock *, struct sk_buff *))
587 struct sk_buff *frag;
588 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
589 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
590 inet6_sk(skb->sk) : NULL;
591 struct ipv6hdr *tmp_hdr;
593 unsigned int mtu, hlen, left, len;
596 int ptr, offset = 0, err = 0;
597 u8 *prevhdr, nexthdr = 0;
599 hlen = ip6_find_1stfragopt(skb, &prevhdr);
602 mtu = ip6_skb_dst_mtu(skb);
604 /* We must not fragment if the socket is set to force MTU discovery
605 * or if the skb it not generated by a local socket.
607 if (unlikely(!skb->ignore_df && skb->len > mtu))
610 if (IP6CB(skb)->frag_max_size) {
611 if (IP6CB(skb)->frag_max_size > mtu)
614 /* don't send fragments larger than what we received */
615 mtu = IP6CB(skb)->frag_max_size;
616 if (mtu < IPV6_MIN_MTU)
620 if (np && np->frag_size < mtu) {
624 if (mtu < hlen + sizeof(struct frag_hdr) + 8)
626 mtu -= hlen + sizeof(struct frag_hdr);
628 frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr,
629 &ipv6_hdr(skb)->saddr);
631 if (skb->ip_summed == CHECKSUM_PARTIAL &&
632 (err = skb_checksum_help(skb)))
635 hroom = LL_RESERVED_SPACE(rt->dst.dev);
636 if (skb_has_frag_list(skb)) {
637 unsigned int first_len = skb_pagelen(skb);
638 struct sk_buff *frag2;
640 if (first_len - hlen > mtu ||
641 ((first_len - hlen) & 7) ||
643 skb_headroom(skb) < (hroom + sizeof(struct frag_hdr)))
646 skb_walk_frags(skb, frag) {
647 /* Correct geometry. */
648 if (frag->len > mtu ||
649 ((frag->len & 7) && frag->next) ||
650 skb_headroom(frag) < (hlen + hroom + sizeof(struct frag_hdr)))
651 goto slow_path_clean;
653 /* Partially cloned skb? */
654 if (skb_shared(frag))
655 goto slow_path_clean;
660 frag->destructor = sock_wfree;
662 skb->truesize -= frag->truesize;
669 *prevhdr = NEXTHDR_FRAGMENT;
670 tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
672 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
673 IPSTATS_MIB_FRAGFAILS);
677 frag = skb_shinfo(skb)->frag_list;
678 skb_frag_list_init(skb);
680 __skb_pull(skb, hlen);
681 fh = (struct frag_hdr *)__skb_push(skb, sizeof(struct frag_hdr));
682 __skb_push(skb, hlen);
683 skb_reset_network_header(skb);
684 memcpy(skb_network_header(skb), tmp_hdr, hlen);
686 fh->nexthdr = nexthdr;
688 fh->frag_off = htons(IP6_MF);
689 fh->identification = frag_id;
691 first_len = skb_pagelen(skb);
692 skb->data_len = first_len - skb_headlen(skb);
693 skb->len = first_len;
694 ipv6_hdr(skb)->payload_len = htons(first_len -
695 sizeof(struct ipv6hdr));
700 /* Prepare header of the next frame,
701 * before previous one went down. */
703 frag->ip_summed = CHECKSUM_NONE;
704 skb_reset_transport_header(frag);
705 fh = (struct frag_hdr *)__skb_push(frag, sizeof(struct frag_hdr));
706 __skb_push(frag, hlen);
707 skb_reset_network_header(frag);
708 memcpy(skb_network_header(frag), tmp_hdr,
710 offset += skb->len - hlen - sizeof(struct frag_hdr);
711 fh->nexthdr = nexthdr;
713 fh->frag_off = htons(offset);
715 fh->frag_off |= htons(IP6_MF);
716 fh->identification = frag_id;
717 ipv6_hdr(frag)->payload_len =
719 sizeof(struct ipv6hdr));
720 ip6_copy_metadata(frag, skb);
723 err = output(net, sk, skb);
725 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
726 IPSTATS_MIB_FRAGCREATES);
739 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
740 IPSTATS_MIB_FRAGOKS);
745 kfree_skb_list(frag);
747 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
748 IPSTATS_MIB_FRAGFAILS);
753 skb_walk_frags(skb, frag2) {
757 frag2->destructor = NULL;
758 skb->truesize += frag2->truesize;
763 left = skb->len - hlen; /* Space per frame */
764 ptr = hlen; /* Where to start from */
767 * Fragment the datagram.
770 *prevhdr = NEXTHDR_FRAGMENT;
771 troom = rt->dst.dev->needed_tailroom;
774 * Keep copying data until we run out.
778 /* IF: it doesn't fit, use 'mtu' - the data space left */
781 /* IF: we are not sending up to and including the packet end
782 then align the next start on an eight byte boundary */
787 /* Allocate buffer */
788 frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
789 hroom + troom, GFP_ATOMIC);
791 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
792 IPSTATS_MIB_FRAGFAILS);
798 * Set up data on packet
801 ip6_copy_metadata(frag, skb);
802 skb_reserve(frag, hroom);
803 skb_put(frag, len + hlen + sizeof(struct frag_hdr));
804 skb_reset_network_header(frag);
805 fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
806 frag->transport_header = (frag->network_header + hlen +
807 sizeof(struct frag_hdr));
810 * Charge the memory for the fragment to any owner
814 skb_set_owner_w(frag, skb->sk);
817 * Copy the packet header into the new buffer.
819 skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
822 * Build fragment header.
824 fh->nexthdr = nexthdr;
826 fh->identification = frag_id;
829 * Copy a block of the IP datagram.
831 BUG_ON(skb_copy_bits(skb, ptr, skb_transport_header(frag),
835 fh->frag_off = htons(offset);
837 fh->frag_off |= htons(IP6_MF);
838 ipv6_hdr(frag)->payload_len = htons(frag->len -
839 sizeof(struct ipv6hdr));
845 * Put this fragment into the sending queue.
847 err = output(net, sk, frag);
851 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
852 IPSTATS_MIB_FRAGCREATES);
854 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
855 IPSTATS_MIB_FRAGOKS);
860 if (skb->sk && dst_allfrag(skb_dst(skb)))
861 sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);
863 skb->dev = skb_dst(skb)->dev;
864 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
868 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
869 IPSTATS_MIB_FRAGFAILS);
874 static inline int ip6_rt_check(const struct rt6key *rt_key,
875 const struct in6_addr *fl_addr,
876 const struct in6_addr *addr_cache)
878 return (rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
879 (!addr_cache || !ipv6_addr_equal(fl_addr, addr_cache));
882 static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
883 struct dst_entry *dst,
884 const struct flowi6 *fl6)
886 struct ipv6_pinfo *np = inet6_sk(sk);
892 if (dst->ops->family != AF_INET6) {
897 rt = (struct rt6_info *)dst;
898 /* Yes, checking route validity in not connected
899 * case is not very simple. Take into account,
900 * that we do not support routing by source, TOS,
901 * and MSG_DONTROUTE --ANK (980726)
903 * 1. ip6_rt_check(): If route was host route,
904 * check that cached destination is current.
905 * If it is network route, we still may
906 * check its validity using saved pointer
907 * to the last used address: daddr_cache.
908 * We do not want to save whole address now,
909 * (because main consumer of this service
910 * is tcp, which has not this problem),
911 * so that the last trick works only on connected
913 * 2. oif also should be the same.
915 if (ip6_rt_check(&rt->rt6i_dst, &fl6->daddr, np->daddr_cache) ||
916 #ifdef CONFIG_IPV6_SUBTREES
917 ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) ||
919 (!(fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF) &&
920 (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex))) {
929 static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
930 struct dst_entry **dst, struct flowi6 *fl6)
932 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
939 /* The correct way to handle this would be to do
940 * ip6_route_get_saddr, and then ip6_route_output; however,
941 * the route-specific preferred source forces the
942 * ip6_route_output call _before_ ip6_route_get_saddr.
944 * In source specific routing (no src=any default route),
945 * ip6_route_output will fail given src=any saddr, though, so
946 * that's why we try it again later.
948 if (ipv6_addr_any(&fl6->saddr) && (!*dst || !(*dst)->error)) {
950 bool had_dst = *dst != NULL;
953 *dst = ip6_route_output(net, sk, fl6);
954 rt = (*dst)->error ? NULL : (struct rt6_info *)*dst;
955 err = ip6_route_get_saddr(net, rt, &fl6->daddr,
956 sk ? inet6_sk(sk)->srcprefs : 0,
959 goto out_err_release;
961 /* If we had an erroneous initial result, pretend it
962 * never existed and let the SA-enabled version take
965 if (!had_dst && (*dst)->error) {
971 flags |= RT6_LOOKUP_F_IFACE;
975 *dst = ip6_route_output_flags(net, sk, fl6, flags);
979 goto out_err_release;
981 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
983 * Here if the dst entry we've looked up
984 * has a neighbour entry that is in the INCOMPLETE
985 * state and the src address from the flow is
986 * marked as OPTIMISTIC, we release the found
987 * dst entry and replace it instead with the
988 * dst entry of the nexthop router
990 rt = (struct rt6_info *) *dst;
992 n = __ipv6_neigh_lookup_noref(rt->dst.dev,
993 rt6_nexthop(rt, &fl6->daddr));
994 err = n && !(n->nud_state & NUD_VALID) ? -EINVAL : 0;
995 rcu_read_unlock_bh();
998 struct inet6_ifaddr *ifp;
999 struct flowi6 fl_gw6;
1002 ifp = ipv6_get_ifaddr(net, &fl6->saddr,
1005 redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
1011 * We need to get the dst entry for the
1012 * default router instead
1015 memcpy(&fl_gw6, fl6, sizeof(struct flowi6));
1016 memset(&fl_gw6.daddr, 0, sizeof(struct in6_addr));
1017 *dst = ip6_route_output(net, sk, &fl_gw6);
1018 err = (*dst)->error;
1020 goto out_err_release;
1024 if (ipv6_addr_v4mapped(&fl6->saddr) &&
1025 !(ipv6_addr_v4mapped(&fl6->daddr) || ipv6_addr_any(&fl6->daddr))) {
1026 err = -EAFNOSUPPORT;
1027 goto out_err_release;
1036 if (err == -ENETUNREACH)
1037 IP6_INC_STATS(net, NULL, IPSTATS_MIB_OUTNOROUTES);
1042 * ip6_dst_lookup - perform route lookup on flow
1043 * @sk: socket which provides route info
1044 * @dst: pointer to dst_entry * for result
1045 * @fl6: flow to lookup
1047 * This function performs a route lookup on the given flow.
1049 * It returns zero on success, or a standard errno code on error.
1051 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1055 return ip6_dst_lookup_tail(net, sk, dst, fl6);
1057 EXPORT_SYMBOL_GPL(ip6_dst_lookup);
1060 * ip6_dst_lookup_flow - perform route lookup on flow with ipsec
1061 * @sk: socket which provides route info
1062 * @fl6: flow to lookup
1063 * @final_dst: final destination address for ipsec lookup
1065 * This function performs a route lookup on the given flow.
1067 * It returns a valid dst pointer on success, or a pointer encoded
1070 struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
1071 const struct in6_addr *final_dst)
1073 struct dst_entry *dst = NULL;
1076 err = ip6_dst_lookup_tail(sock_net(sk), sk, &dst, fl6);
1078 return ERR_PTR(err);
1080 fl6->daddr = *final_dst;
1082 return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
1084 EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow);
1087 * ip6_sk_dst_lookup_flow - perform socket cached route lookup on flow
1088 * @sk: socket which provides the dst cache and route info
1089 * @fl6: flow to lookup
1090 * @final_dst: final destination address for ipsec lookup
1092 * This function performs a route lookup on the given flow with the
1093 * possibility of using the cached route in the socket if it is valid.
1094 * It will take the socket dst lock when operating on the dst cache.
1095 * As a result, this function can only be used in process context.
1097 * It returns a valid dst pointer on success, or a pointer encoded
1100 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1101 const struct in6_addr *final_dst)
1103 struct dst_entry *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
1105 dst = ip6_sk_dst_check(sk, dst, fl6);
1107 dst = ip6_dst_lookup_flow(sk, fl6, final_dst);
1111 EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup_flow);
1113 static inline int ip6_ufo_append_data(struct sock *sk,
1114 struct sk_buff_head *queue,
1115 int getfrag(void *from, char *to, int offset, int len,
1116 int odd, struct sk_buff *skb),
1117 void *from, int length, int hh_len, int fragheaderlen,
1118 int exthdrlen, int transhdrlen, int mtu,
1119 unsigned int flags, const struct flowi6 *fl6)
1122 struct sk_buff *skb;
1125 /* There is support for UDP large send offload by network
1126 * device, so create one single skb packet containing complete
1129 skb = skb_peek_tail(queue);
1131 skb = sock_alloc_send_skb(sk,
1132 hh_len + fragheaderlen + transhdrlen + 20,
1133 (flags & MSG_DONTWAIT), &err);
1137 /* reserve space for Hardware header */
1138 skb_reserve(skb, hh_len);
1140 /* create space for UDP/IP header */
1141 skb_put(skb, fragheaderlen + transhdrlen);
1143 /* initialize network header pointer */
1144 skb_set_network_header(skb, exthdrlen);
1146 /* initialize protocol header pointer */
1147 skb->transport_header = skb->network_header + fragheaderlen;
1149 skb->protocol = htons(ETH_P_IPV6);
1152 __skb_queue_tail(queue, skb);
1153 } else if (skb_is_gso(skb)) {
1157 skb->ip_summed = CHECKSUM_PARTIAL;
1158 /* Specify the length of each IPv6 datagram fragment.
1159 * It has to be a multiple of 8.
1161 skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
1162 sizeof(struct frag_hdr)) & ~7;
1163 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
1164 skb_shinfo(skb)->ip6_frag_id = ipv6_select_ident(sock_net(sk),
1169 return skb_append_datato_frags(sk, skb, getfrag, from,
1170 (length - transhdrlen));
1173 static inline struct ipv6_opt_hdr *ip6_opt_dup(struct ipv6_opt_hdr *src,
1176 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1179 static inline struct ipv6_rt_hdr *ip6_rthdr_dup(struct ipv6_rt_hdr *src,
1182 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1185 static void ip6_append_data_mtu(unsigned int *mtu,
1187 unsigned int fragheaderlen,
1188 struct sk_buff *skb,
1189 struct rt6_info *rt,
1190 unsigned int orig_mtu)
1192 if (!(rt->dst.flags & DST_XFRM_TUNNEL)) {
1194 /* first fragment, reserve header_len */
1195 *mtu = orig_mtu - rt->dst.header_len;
1199 * this fragment is not first, the headers
1200 * space is regarded as data space.
1204 *maxfraglen = ((*mtu - fragheaderlen) & ~7)
1205 + fragheaderlen - sizeof(struct frag_hdr);
1209 static int ip6_setup_cork(struct sock *sk, struct inet_cork_full *cork,
1210 struct inet6_cork *v6_cork, struct ipcm6_cookie *ipc6,
1211 struct rt6_info *rt, struct flowi6 *fl6)
1213 struct ipv6_pinfo *np = inet6_sk(sk);
1215 struct ipv6_txoptions *opt = ipc6->opt;
1221 if (WARN_ON(v6_cork->opt))
1224 v6_cork->opt = kzalloc(opt->tot_len, sk->sk_allocation);
1225 if (unlikely(!v6_cork->opt))
1228 v6_cork->opt->tot_len = opt->tot_len;
1229 v6_cork->opt->opt_flen = opt->opt_flen;
1230 v6_cork->opt->opt_nflen = opt->opt_nflen;
1232 v6_cork->opt->dst0opt = ip6_opt_dup(opt->dst0opt,
1234 if (opt->dst0opt && !v6_cork->opt->dst0opt)
1237 v6_cork->opt->dst1opt = ip6_opt_dup(opt->dst1opt,
1239 if (opt->dst1opt && !v6_cork->opt->dst1opt)
1242 v6_cork->opt->hopopt = ip6_opt_dup(opt->hopopt,
1244 if (opt->hopopt && !v6_cork->opt->hopopt)
1247 v6_cork->opt->srcrt = ip6_rthdr_dup(opt->srcrt,
1249 if (opt->srcrt && !v6_cork->opt->srcrt)
1252 /* need source address above miyazawa*/
1255 cork->base.dst = &rt->dst;
1256 cork->fl.u.ip6 = *fl6;
1257 v6_cork->hop_limit = ipc6->hlimit;
1258 v6_cork->tclass = ipc6->tclass;
1259 if (rt->dst.flags & DST_XFRM_TUNNEL)
1260 mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ?
1261 rt->dst.dev->mtu : dst_mtu(&rt->dst);
1263 mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ?
1264 rt->dst.dev->mtu : dst_mtu(rt->dst.path);
1265 if (np->frag_size < mtu) {
1267 mtu = np->frag_size;
1269 cork->base.fragsize = mtu;
1270 if (dst_allfrag(rt->dst.path))
1271 cork->base.flags |= IPCORK_ALLFRAG;
1272 cork->base.length = 0;
1277 static int __ip6_append_data(struct sock *sk,
1279 struct sk_buff_head *queue,
1280 struct inet_cork *cork,
1281 struct inet6_cork *v6_cork,
1282 struct page_frag *pfrag,
1283 int getfrag(void *from, char *to, int offset,
1284 int len, int odd, struct sk_buff *skb),
1285 void *from, int length, int transhdrlen,
1286 unsigned int flags, struct ipcm6_cookie *ipc6,
1287 const struct sockcm_cookie *sockc)
1289 struct sk_buff *skb, *skb_prev = NULL;
1290 unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu;
1292 int dst_exthdrlen = 0;
1299 struct rt6_info *rt = (struct rt6_info *)cork->dst;
1300 struct ipv6_txoptions *opt = v6_cork->opt;
1301 int csummode = CHECKSUM_NONE;
1302 unsigned int maxnonfragsize, headersize;
1304 skb = skb_peek_tail(queue);
1306 exthdrlen = opt ? opt->opt_flen : 0;
1307 dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len;
1310 mtu = cork->fragsize;
1313 hh_len = LL_RESERVED_SPACE(rt->dst.dev);
1315 fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len +
1316 (opt ? opt->opt_nflen : 0);
1317 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen -
1318 sizeof(struct frag_hdr);
1320 headersize = sizeof(struct ipv6hdr) +
1321 (opt ? opt->opt_flen + opt->opt_nflen : 0) +
1322 (dst_allfrag(&rt->dst) ?
1323 sizeof(struct frag_hdr) : 0) +
1324 rt->rt6i_nfheader_len;
1326 if (cork->length + length > mtu - headersize && ipc6->dontfrag &&
1327 (sk->sk_protocol == IPPROTO_UDP ||
1328 sk->sk_protocol == IPPROTO_RAW)) {
1329 ipv6_local_rxpmtu(sk, fl6, mtu - headersize +
1330 sizeof(struct ipv6hdr));
1334 if (ip6_sk_ignore_df(sk))
1335 maxnonfragsize = sizeof(struct ipv6hdr) + IPV6_MAXPLEN;
1337 maxnonfragsize = mtu;
1339 if (cork->length + length > maxnonfragsize - headersize) {
1341 ipv6_local_error(sk, EMSGSIZE, fl6,
1343 sizeof(struct ipv6hdr));
1347 /* CHECKSUM_PARTIAL only with no extension headers and when
1348 * we are not going to fragment
1350 if (transhdrlen && sk->sk_protocol == IPPROTO_UDP &&
1351 headersize == sizeof(struct ipv6hdr) &&
1352 length <= mtu - headersize &&
1353 !(flags & MSG_MORE) &&
1354 rt->dst.dev->features & (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))
1355 csummode = CHECKSUM_PARTIAL;
1357 if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) {
1358 sock_tx_timestamp(sk, sockc->tsflags, &tx_flags);
1359 if (tx_flags & SKBTX_ANY_SW_TSTAMP &&
1360 sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
1361 tskey = sk->sk_tskey++;
1365 * Let's try using as much space as possible.
1366 * Use MTU if total length of the message fits into the MTU.
1367 * Otherwise, we need to reserve fragment header and
1368 * fragment alignment (= 8-15 octects, in total).
1370 * Note that we may need to "move" the data from the tail of
1371 * of the buffer to the new fragment when we split
1374 * FIXME: It may be fragmented into multiple chunks
1375 * at once if non-fragmentable extension headers
1380 cork->length += length;
1381 if ((((length + fragheaderlen) > mtu) ||
1382 (skb && skb_is_gso(skb))) &&
1383 (sk->sk_protocol == IPPROTO_UDP) &&
1384 (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len &&
1385 (sk->sk_type == SOCK_DGRAM) && !udp_get_no_check6_tx(sk)) {
1386 err = ip6_ufo_append_data(sk, queue, getfrag, from, length,
1387 hh_len, fragheaderlen, exthdrlen,
1388 transhdrlen, mtu, flags, fl6);
1397 while (length > 0) {
1398 /* Check if the remaining data fits into current packet. */
1399 copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
1401 copy = maxfraglen - skb->len;
1405 unsigned int datalen;
1406 unsigned int fraglen;
1407 unsigned int fraggap;
1408 unsigned int alloclen;
1410 /* There's no room in the current skb */
1412 fraggap = skb->len - maxfraglen;
1415 /* update mtu and maxfraglen if necessary */
1416 if (!skb || !skb_prev)
1417 ip6_append_data_mtu(&mtu, &maxfraglen,
1418 fragheaderlen, skb, rt,
1424 * If remaining data exceeds the mtu,
1425 * we know we need more fragment(s).
1427 datalen = length + fraggap;
1429 if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
1430 datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len;
1431 if ((flags & MSG_MORE) &&
1432 !(rt->dst.dev->features&NETIF_F_SG))
1435 alloclen = datalen + fragheaderlen;
1437 alloclen += dst_exthdrlen;
1439 if (datalen != length + fraggap) {
1441 * this is not the last fragment, the trailer
1442 * space is regarded as data space.
1444 datalen += rt->dst.trailer_len;
1447 alloclen += rt->dst.trailer_len;
1448 fraglen = datalen + fragheaderlen;
1451 * We just reserve space for fragment header.
1452 * Note: this may be overallocation if the message
1453 * (without MSG_MORE) fits into the MTU.
1455 alloclen += sizeof(struct frag_hdr);
1458 skb = sock_alloc_send_skb(sk,
1460 (flags & MSG_DONTWAIT), &err);
1463 if (atomic_read(&sk->sk_wmem_alloc) <=
1465 skb = sock_wmalloc(sk,
1466 alloclen + hh_len, 1,
1474 * Fill in the control structures
1476 skb->protocol = htons(ETH_P_IPV6);
1477 skb->ip_summed = csummode;
1479 /* reserve for fragmentation and ipsec header */
1480 skb_reserve(skb, hh_len + sizeof(struct frag_hdr) +
1483 /* Only the initial fragment is time stamped */
1484 skb_shinfo(skb)->tx_flags = tx_flags;
1486 skb_shinfo(skb)->tskey = tskey;
1490 * Find where to start putting bytes
1492 data = skb_put(skb, fraglen);
1493 skb_set_network_header(skb, exthdrlen);
1494 data += fragheaderlen;
1495 skb->transport_header = (skb->network_header +
1498 skb->csum = skb_copy_and_csum_bits(
1499 skb_prev, maxfraglen,
1500 data + transhdrlen, fraggap, 0);
1501 skb_prev->csum = csum_sub(skb_prev->csum,
1504 pskb_trim_unique(skb_prev, maxfraglen);
1506 copy = datalen - transhdrlen - fraggap;
1512 } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
1519 length -= datalen - fraggap;
1525 * Put the packet on the pending queue
1527 __skb_queue_tail(queue, skb);
1534 if (!(rt->dst.dev->features&NETIF_F_SG)) {
1538 if (getfrag(from, skb_put(skb, copy),
1539 offset, copy, off, skb) < 0) {
1540 __skb_trim(skb, off);
1545 int i = skb_shinfo(skb)->nr_frags;
1548 if (!sk_page_frag_refill(sk, pfrag))
1551 if (!skb_can_coalesce(skb, i, pfrag->page,
1554 if (i == MAX_SKB_FRAGS)
1557 __skb_fill_page_desc(skb, i, pfrag->page,
1559 skb_shinfo(skb)->nr_frags = ++i;
1560 get_page(pfrag->page);
1562 copy = min_t(int, copy, pfrag->size - pfrag->offset);
1564 page_address(pfrag->page) + pfrag->offset,
1565 offset, copy, skb->len, skb) < 0)
1568 pfrag->offset += copy;
1569 skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
1571 skb->data_len += copy;
1572 skb->truesize += copy;
1573 atomic_add(copy, &sk->sk_wmem_alloc);
1584 cork->length -= length;
1585 IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
1589 int ip6_append_data(struct sock *sk,
1590 int getfrag(void *from, char *to, int offset, int len,
1591 int odd, struct sk_buff *skb),
1592 void *from, int length, int transhdrlen,
1593 struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1594 struct rt6_info *rt, unsigned int flags,
1595 const struct sockcm_cookie *sockc)
1597 struct inet_sock *inet = inet_sk(sk);
1598 struct ipv6_pinfo *np = inet6_sk(sk);
1602 if (flags&MSG_PROBE)
1604 if (skb_queue_empty(&sk->sk_write_queue)) {
1608 err = ip6_setup_cork(sk, &inet->cork, &np->cork,
1613 exthdrlen = (ipc6->opt ? ipc6->opt->opt_flen : 0);
1614 length += exthdrlen;
1615 transhdrlen += exthdrlen;
1617 fl6 = &inet->cork.fl.u.ip6;
1621 return __ip6_append_data(sk, fl6, &sk->sk_write_queue, &inet->cork.base,
1622 &np->cork, sk_page_frag(sk), getfrag,
1623 from, length, transhdrlen, flags, ipc6, sockc);
1625 EXPORT_SYMBOL_GPL(ip6_append_data);
1627 static void ip6_cork_release(struct inet_cork_full *cork,
1628 struct inet6_cork *v6_cork)
1631 kfree(v6_cork->opt->dst0opt);
1632 kfree(v6_cork->opt->dst1opt);
1633 kfree(v6_cork->opt->hopopt);
1634 kfree(v6_cork->opt->srcrt);
1635 kfree(v6_cork->opt);
1636 v6_cork->opt = NULL;
1639 if (cork->base.dst) {
1640 dst_release(cork->base.dst);
1641 cork->base.dst = NULL;
1642 cork->base.flags &= ~IPCORK_ALLFRAG;
1644 memset(&cork->fl, 0, sizeof(cork->fl));
1647 struct sk_buff *__ip6_make_skb(struct sock *sk,
1648 struct sk_buff_head *queue,
1649 struct inet_cork_full *cork,
1650 struct inet6_cork *v6_cork)
1652 struct sk_buff *skb, *tmp_skb;
1653 struct sk_buff **tail_skb;
1654 struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
1655 struct ipv6_pinfo *np = inet6_sk(sk);
1656 struct net *net = sock_net(sk);
1657 struct ipv6hdr *hdr;
1658 struct ipv6_txoptions *opt = v6_cork->opt;
1659 struct rt6_info *rt = (struct rt6_info *)cork->base.dst;
1660 struct flowi6 *fl6 = &cork->fl.u.ip6;
1661 unsigned char proto = fl6->flowi6_proto;
1663 skb = __skb_dequeue(queue);
1666 tail_skb = &(skb_shinfo(skb)->frag_list);
1668 /* move skb->data to ip header from ext header */
1669 if (skb->data < skb_network_header(skb))
1670 __skb_pull(skb, skb_network_offset(skb));
1671 while ((tmp_skb = __skb_dequeue(queue)) != NULL) {
1672 __skb_pull(tmp_skb, skb_network_header_len(skb));
1673 *tail_skb = tmp_skb;
1674 tail_skb = &(tmp_skb->next);
1675 skb->len += tmp_skb->len;
1676 skb->data_len += tmp_skb->len;
1677 skb->truesize += tmp_skb->truesize;
1678 tmp_skb->destructor = NULL;
1682 /* Allow local fragmentation. */
1683 skb->ignore_df = ip6_sk_ignore_df(sk);
1685 *final_dst = fl6->daddr;
1686 __skb_pull(skb, skb_network_header_len(skb));
1687 if (opt && opt->opt_flen)
1688 ipv6_push_frag_opts(skb, opt, &proto);
1689 if (opt && opt->opt_nflen)
1690 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst, &fl6->saddr);
1692 skb_push(skb, sizeof(struct ipv6hdr));
1693 skb_reset_network_header(skb);
1694 hdr = ipv6_hdr(skb);
1696 ip6_flow_hdr(hdr, v6_cork->tclass,
1697 ip6_make_flowlabel(net, skb, fl6->flowlabel,
1698 np->autoflowlabel, fl6));
1699 hdr->hop_limit = v6_cork->hop_limit;
1700 hdr->nexthdr = proto;
1701 hdr->saddr = fl6->saddr;
1702 hdr->daddr = *final_dst;
1704 skb->priority = sk->sk_priority;
1705 skb->mark = sk->sk_mark;
1707 skb_dst_set(skb, dst_clone(&rt->dst));
1708 IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len);
1709 if (proto == IPPROTO_ICMPV6) {
1710 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
1712 ICMP6MSGOUT_INC_STATS(net, idev, icmp6_hdr(skb)->icmp6_type);
1713 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1716 ip6_cork_release(cork, v6_cork);
1721 int ip6_send_skb(struct sk_buff *skb)
1723 struct net *net = sock_net(skb->sk);
1724 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
1727 err = ip6_local_out(net, skb->sk, skb);
1730 err = net_xmit_errno(err);
1732 IP6_INC_STATS(net, rt->rt6i_idev,
1733 IPSTATS_MIB_OUTDISCARDS);
1739 int ip6_push_pending_frames(struct sock *sk)
1741 struct sk_buff *skb;
1743 skb = ip6_finish_skb(sk);
1747 return ip6_send_skb(skb);
1749 EXPORT_SYMBOL_GPL(ip6_push_pending_frames);
1751 static void __ip6_flush_pending_frames(struct sock *sk,
1752 struct sk_buff_head *queue,
1753 struct inet_cork_full *cork,
1754 struct inet6_cork *v6_cork)
1756 struct sk_buff *skb;
1758 while ((skb = __skb_dequeue_tail(queue)) != NULL) {
1760 IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb_dst(skb)),
1761 IPSTATS_MIB_OUTDISCARDS);
1765 ip6_cork_release(cork, v6_cork);
1768 void ip6_flush_pending_frames(struct sock *sk)
1770 __ip6_flush_pending_frames(sk, &sk->sk_write_queue,
1771 &inet_sk(sk)->cork, &inet6_sk(sk)->cork);
1773 EXPORT_SYMBOL_GPL(ip6_flush_pending_frames);
1775 struct sk_buff *ip6_make_skb(struct sock *sk,
1776 int getfrag(void *from, char *to, int offset,
1777 int len, int odd, struct sk_buff *skb),
1778 void *from, int length, int transhdrlen,
1779 struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1780 struct rt6_info *rt, unsigned int flags,
1781 const struct sockcm_cookie *sockc)
1783 struct inet_cork_full cork;
1784 struct inet6_cork v6_cork;
1785 struct sk_buff_head queue;
1786 int exthdrlen = (ipc6->opt ? ipc6->opt->opt_flen : 0);
1789 if (flags & MSG_PROBE)
1792 __skb_queue_head_init(&queue);
1794 cork.base.flags = 0;
1796 cork.base.opt = NULL;
1798 err = ip6_setup_cork(sk, &cork, &v6_cork, ipc6, rt, fl6);
1800 return ERR_PTR(err);
1802 if (ipc6->dontfrag < 0)
1803 ipc6->dontfrag = inet6_sk(sk)->dontfrag;
1805 err = __ip6_append_data(sk, fl6, &queue, &cork.base, &v6_cork,
1806 ¤t->task_frag, getfrag, from,
1807 length + exthdrlen, transhdrlen + exthdrlen,
1808 flags, ipc6, sockc);
1810 __ip6_flush_pending_frames(sk, &queue, &cork, &v6_cork);
1811 return ERR_PTR(err);
1814 return __ip6_make_skb(sk, &queue, &cork, &v6_cork);