xref: /openbmc/linux/net/ipv6/ip6_output.c (revision e1f52208bb968291f7d9142eff60b62984b4a511)
11da177e4SLinus Torvalds /*
21da177e4SLinus Torvalds  *	IPv6 output functions
31da177e4SLinus Torvalds  *	Linux INET6 implementation
41da177e4SLinus Torvalds  *
51da177e4SLinus Torvalds  *	Authors:
61da177e4SLinus Torvalds  *	Pedro Roque		<roque@di.fc.ul.pt>
71da177e4SLinus Torvalds  *
81da177e4SLinus Torvalds  *	$Id: ip6_output.c,v 1.34 2002/02/01 22:01:04 davem Exp $
91da177e4SLinus Torvalds  *
101da177e4SLinus Torvalds  *	Based on linux/net/ipv4/ip_output.c
111da177e4SLinus Torvalds  *
121da177e4SLinus Torvalds  *	This program is free software; you can redistribute it and/or
131da177e4SLinus Torvalds  *      modify it under the terms of the GNU General Public License
141da177e4SLinus Torvalds  *      as published by the Free Software Foundation; either version
151da177e4SLinus Torvalds  *      2 of the License, or (at your option) any later version.
161da177e4SLinus Torvalds  *
171da177e4SLinus Torvalds  *	Changes:
181da177e4SLinus Torvalds  *	A.N.Kuznetsov	:	airthmetics in fragmentation.
191da177e4SLinus Torvalds  *				extension headers are implemented.
201da177e4SLinus Torvalds  *				route changes now work.
211da177e4SLinus Torvalds  *				ip6_forward does not confuse sniffers.
221da177e4SLinus Torvalds  *				etc.
231da177e4SLinus Torvalds  *
241da177e4SLinus Torvalds  *      H. von Brand    :       Added missing #include <linux/string.h>
251da177e4SLinus Torvalds  *	Imran Patel	: 	frag id should be in NBO
261da177e4SLinus Torvalds  *      Kazunori MIYAZAWA @USAGI
271da177e4SLinus Torvalds  *			:       add ip6_append_data and related functions
281da177e4SLinus Torvalds  *				for datagram xmit
291da177e4SLinus Torvalds  */
301da177e4SLinus Torvalds 
311da177e4SLinus Torvalds #include <linux/errno.h>
321da177e4SLinus Torvalds #include <linux/types.h>
331da177e4SLinus Torvalds #include <linux/string.h>
341da177e4SLinus Torvalds #include <linux/socket.h>
351da177e4SLinus Torvalds #include <linux/net.h>
361da177e4SLinus Torvalds #include <linux/netdevice.h>
371da177e4SLinus Torvalds #include <linux/if_arp.h>
381da177e4SLinus Torvalds #include <linux/in6.h>
391da177e4SLinus Torvalds #include <linux/tcp.h>
401da177e4SLinus Torvalds #include <linux/route.h>
41b59f45d0SHerbert Xu #include <linux/module.h>
421da177e4SLinus Torvalds 
431da177e4SLinus Torvalds #include <linux/netfilter.h>
441da177e4SLinus Torvalds #include <linux/netfilter_ipv6.h>
451da177e4SLinus Torvalds 
461da177e4SLinus Torvalds #include <net/sock.h>
471da177e4SLinus Torvalds #include <net/snmp.h>
481da177e4SLinus Torvalds 
491da177e4SLinus Torvalds #include <net/ipv6.h>
501da177e4SLinus Torvalds #include <net/ndisc.h>
511da177e4SLinus Torvalds #include <net/protocol.h>
521da177e4SLinus Torvalds #include <net/ip6_route.h>
531da177e4SLinus Torvalds #include <net/addrconf.h>
541da177e4SLinus Torvalds #include <net/rawv6.h>
551da177e4SLinus Torvalds #include <net/icmp.h>
561da177e4SLinus Torvalds #include <net/xfrm.h>
571da177e4SLinus Torvalds #include <net/checksum.h>
581da177e4SLinus Torvalds 
591da177e4SLinus Torvalds static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
601da177e4SLinus Torvalds 
611da177e4SLinus Torvalds static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr)
621da177e4SLinus Torvalds {
631da177e4SLinus Torvalds 	static u32 ipv6_fragmentation_id = 1;
641da177e4SLinus Torvalds 	static DEFINE_SPINLOCK(ip6_id_lock);
651da177e4SLinus Torvalds 
661da177e4SLinus Torvalds 	spin_lock_bh(&ip6_id_lock);
671da177e4SLinus Torvalds 	fhdr->identification = htonl(ipv6_fragmentation_id);
681da177e4SLinus Torvalds 	if (++ipv6_fragmentation_id == 0)
691da177e4SLinus Torvalds 		ipv6_fragmentation_id = 1;
701da177e4SLinus Torvalds 	spin_unlock_bh(&ip6_id_lock);
711da177e4SLinus Torvalds }
721da177e4SLinus Torvalds 
731da177e4SLinus Torvalds static inline int ip6_output_finish(struct sk_buff *skb)
741da177e4SLinus Torvalds {
751da177e4SLinus Torvalds 	struct dst_entry *dst = skb->dst;
761da177e4SLinus Torvalds 
773644f0ceSStephen Hemminger 	if (dst->hh)
783644f0ceSStephen Hemminger 		return neigh_hh_output(dst->hh, skb);
793644f0ceSStephen Hemminger 	else if (dst->neighbour)
801da177e4SLinus Torvalds 		return dst->neighbour->output(skb);
811da177e4SLinus Torvalds 
82a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
831da177e4SLinus Torvalds 	kfree_skb(skb);
841da177e4SLinus Torvalds 	return -EINVAL;
851da177e4SLinus Torvalds 
861da177e4SLinus Torvalds }
871da177e4SLinus Torvalds 
881da177e4SLinus Torvalds /* dev_loopback_xmit for use with netfilter. */
891da177e4SLinus Torvalds static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
901da177e4SLinus Torvalds {
91459a98edSArnaldo Carvalho de Melo 	skb_reset_mac_header(newskb);
92bbe735e4SArnaldo Carvalho de Melo 	__skb_pull(newskb, skb_network_offset(newskb));
931da177e4SLinus Torvalds 	newskb->pkt_type = PACKET_LOOPBACK;
941da177e4SLinus Torvalds 	newskb->ip_summed = CHECKSUM_UNNECESSARY;
951da177e4SLinus Torvalds 	BUG_TRAP(newskb->dst);
961da177e4SLinus Torvalds 
971da177e4SLinus Torvalds 	netif_rx(newskb);
981da177e4SLinus Torvalds 	return 0;
991da177e4SLinus Torvalds }
1001da177e4SLinus Torvalds 
1011da177e4SLinus Torvalds 
1021da177e4SLinus Torvalds static int ip6_output2(struct sk_buff *skb)
1031da177e4SLinus Torvalds {
1041da177e4SLinus Torvalds 	struct dst_entry *dst = skb->dst;
1051da177e4SLinus Torvalds 	struct net_device *dev = dst->dev;
1061da177e4SLinus Torvalds 
1071da177e4SLinus Torvalds 	skb->protocol = htons(ETH_P_IPV6);
1081da177e4SLinus Torvalds 	skb->dev = dev;
1091da177e4SLinus Torvalds 
1100660e03fSArnaldo Carvalho de Melo 	if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
1111da177e4SLinus Torvalds 		struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL;
112a11d206dSYOSHIFUJI Hideaki 		struct inet6_dev *idev = ip6_dst_idev(skb->dst);
1131da177e4SLinus Torvalds 
1141da177e4SLinus Torvalds 		if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) &&
1150660e03fSArnaldo Carvalho de Melo 		    ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
1160660e03fSArnaldo Carvalho de Melo 					&ipv6_hdr(skb)->saddr)) {
1171da177e4SLinus Torvalds 			struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
1181da177e4SLinus Torvalds 
1191da177e4SLinus Torvalds 			/* Do not check for IFF_ALLMULTI; multicast routing
1201da177e4SLinus Torvalds 			   is not supported in any case.
1211da177e4SLinus Torvalds 			 */
1221da177e4SLinus Torvalds 			if (newskb)
1231da177e4SLinus Torvalds 				NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL,
1241da177e4SLinus Torvalds 					newskb->dev,
1251da177e4SLinus Torvalds 					ip6_dev_loopback_xmit);
1261da177e4SLinus Torvalds 
1270660e03fSArnaldo Carvalho de Melo 			if (ipv6_hdr(skb)->hop_limit == 0) {
128a11d206dSYOSHIFUJI Hideaki 				IP6_INC_STATS(idev, IPSTATS_MIB_OUTDISCARDS);
1291da177e4SLinus Torvalds 				kfree_skb(skb);
1301da177e4SLinus Torvalds 				return 0;
1311da177e4SLinus Torvalds 			}
1321da177e4SLinus Torvalds 		}
1331da177e4SLinus Torvalds 
134a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS(idev, IPSTATS_MIB_OUTMCASTPKTS);
1351da177e4SLinus Torvalds 	}
1361da177e4SLinus Torvalds 
1371da177e4SLinus Torvalds 	return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish);
1381da177e4SLinus Torvalds }
1391da177e4SLinus Torvalds 
140628a5c56SJohn Heffner static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
141628a5c56SJohn Heffner {
142628a5c56SJohn Heffner 	struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
143628a5c56SJohn Heffner 
144628a5c56SJohn Heffner 	return (np && np->pmtudisc == IPV6_PMTUDISC_PROBE) ?
145628a5c56SJohn Heffner 	       skb->dst->dev->mtu : dst_mtu(skb->dst);
146628a5c56SJohn Heffner }
147628a5c56SJohn Heffner 
1481da177e4SLinus Torvalds int ip6_output(struct sk_buff *skb)
1491da177e4SLinus Torvalds {
150628a5c56SJohn Heffner 	if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
151e89e9cf5SAnanda Raju 				dst_allfrag(skb->dst))
1521da177e4SLinus Torvalds 		return ip6_fragment(skb, ip6_output2);
1531da177e4SLinus Torvalds 	else
1541da177e4SLinus Torvalds 		return ip6_output2(skb);
1551da177e4SLinus Torvalds }
1561da177e4SLinus Torvalds 
1571da177e4SLinus Torvalds /*
1581da177e4SLinus Torvalds  *	xmit an sk_buff (used by TCP)
1591da177e4SLinus Torvalds  */
1601da177e4SLinus Torvalds 
1611da177e4SLinus Torvalds int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
1621da177e4SLinus Torvalds 	     struct ipv6_txoptions *opt, int ipfragok)
1631da177e4SLinus Torvalds {
164b30bd282SPatrick McHardy 	struct ipv6_pinfo *np = inet6_sk(sk);
1651da177e4SLinus Torvalds 	struct in6_addr *first_hop = &fl->fl6_dst;
1661da177e4SLinus Torvalds 	struct dst_entry *dst = skb->dst;
1671da177e4SLinus Torvalds 	struct ipv6hdr *hdr;
1681da177e4SLinus Torvalds 	u8  proto = fl->proto;
1691da177e4SLinus Torvalds 	int seg_len = skb->len;
17041a1f8eaSYOSHIFUJI Hideaki 	int hlimit, tclass;
1711da177e4SLinus Torvalds 	u32 mtu;
1721da177e4SLinus Torvalds 
1731da177e4SLinus Torvalds 	if (opt) {
1741da177e4SLinus Torvalds 		int head_room;
1751da177e4SLinus Torvalds 
1761da177e4SLinus Torvalds 		/* First: exthdrs may take lots of space (~8K for now)
1771da177e4SLinus Torvalds 		   MAX_HEADER is not enough.
1781da177e4SLinus Torvalds 		 */
1791da177e4SLinus Torvalds 		head_room = opt->opt_nflen + opt->opt_flen;
1801da177e4SLinus Torvalds 		seg_len += head_room;
1811da177e4SLinus Torvalds 		head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
1821da177e4SLinus Torvalds 
1831da177e4SLinus Torvalds 		if (skb_headroom(skb) < head_room) {
1841da177e4SLinus Torvalds 			struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
185a11d206dSYOSHIFUJI Hideaki 			if (skb2 == NULL) {
186a11d206dSYOSHIFUJI Hideaki 				IP6_INC_STATS(ip6_dst_idev(skb->dst),
187a11d206dSYOSHIFUJI Hideaki 					      IPSTATS_MIB_OUTDISCARDS);
1881da177e4SLinus Torvalds 				kfree_skb(skb);
1891da177e4SLinus Torvalds 				return -ENOBUFS;
1901da177e4SLinus Torvalds 			}
191a11d206dSYOSHIFUJI Hideaki 			kfree_skb(skb);
192a11d206dSYOSHIFUJI Hideaki 			skb = skb2;
1931da177e4SLinus Torvalds 			if (sk)
1941da177e4SLinus Torvalds 				skb_set_owner_w(skb, sk);
1951da177e4SLinus Torvalds 		}
1961da177e4SLinus Torvalds 		if (opt->opt_flen)
1971da177e4SLinus Torvalds 			ipv6_push_frag_opts(skb, opt, &proto);
1981da177e4SLinus Torvalds 		if (opt->opt_nflen)
1991da177e4SLinus Torvalds 			ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
2001da177e4SLinus Torvalds 	}
2011da177e4SLinus Torvalds 
202e2d1bca7SArnaldo Carvalho de Melo 	skb_push(skb, sizeof(struct ipv6hdr));
203e2d1bca7SArnaldo Carvalho de Melo 	skb_reset_network_header(skb);
2040660e03fSArnaldo Carvalho de Melo 	hdr = ipv6_hdr(skb);
2051da177e4SLinus Torvalds 
2061da177e4SLinus Torvalds 	/*
2071da177e4SLinus Torvalds 	 *	Fill in the IPv6 header
2081da177e4SLinus Torvalds 	 */
2091da177e4SLinus Torvalds 
2101da177e4SLinus Torvalds 	hlimit = -1;
2111da177e4SLinus Torvalds 	if (np)
2121da177e4SLinus Torvalds 		hlimit = np->hop_limit;
2131da177e4SLinus Torvalds 	if (hlimit < 0)
2141da177e4SLinus Torvalds 		hlimit = dst_metric(dst, RTAX_HOPLIMIT);
2151da177e4SLinus Torvalds 	if (hlimit < 0)
2161da177e4SLinus Torvalds 		hlimit = ipv6_get_hoplimit(dst->dev);
2171da177e4SLinus Torvalds 
21841a1f8eaSYOSHIFUJI Hideaki 	tclass = -1;
21941a1f8eaSYOSHIFUJI Hideaki 	if (np)
22041a1f8eaSYOSHIFUJI Hideaki 		tclass = np->tclass;
22141a1f8eaSYOSHIFUJI Hideaki 	if (tclass < 0)
22241a1f8eaSYOSHIFUJI Hideaki 		tclass = 0;
22341a1f8eaSYOSHIFUJI Hideaki 
22490bcaf7bSAl Viro 	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel;
22541a1f8eaSYOSHIFUJI Hideaki 
2261da177e4SLinus Torvalds 	hdr->payload_len = htons(seg_len);
2271da177e4SLinus Torvalds 	hdr->nexthdr = proto;
2281da177e4SLinus Torvalds 	hdr->hop_limit = hlimit;
2291da177e4SLinus Torvalds 
2301da177e4SLinus Torvalds 	ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
2311da177e4SLinus Torvalds 	ipv6_addr_copy(&hdr->daddr, first_hop);
2321da177e4SLinus Torvalds 
233a2c2064fSPatrick McHardy 	skb->priority = sk->sk_priority;
234a2c2064fSPatrick McHardy 
2351da177e4SLinus Torvalds 	mtu = dst_mtu(dst);
23689114afdSHerbert Xu 	if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) {
237a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS(ip6_dst_idev(skb->dst),
238a11d206dSYOSHIFUJI Hideaki 			      IPSTATS_MIB_OUTREQUESTS);
2396869c4d8SHarald Welte 		return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev,
2406869c4d8SHarald Welte 				dst_output);
2411da177e4SLinus Torvalds 	}
2421da177e4SLinus Torvalds 
2431da177e4SLinus Torvalds 	if (net_ratelimit())
2441da177e4SLinus Torvalds 		printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
2451da177e4SLinus Torvalds 	skb->dev = dst->dev;
2461da177e4SLinus Torvalds 	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
247a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
2481da177e4SLinus Torvalds 	kfree_skb(skb);
2491da177e4SLinus Torvalds 	return -EMSGSIZE;
2501da177e4SLinus Torvalds }
2511da177e4SLinus Torvalds 
2527159039aSYOSHIFUJI Hideaki EXPORT_SYMBOL(ip6_xmit);
2537159039aSYOSHIFUJI Hideaki 
2541da177e4SLinus Torvalds /*
2551da177e4SLinus Torvalds  *	To avoid extra problems ND packets are send through this
2561da177e4SLinus Torvalds  *	routine. It's code duplication but I really want to avoid
2571da177e4SLinus Torvalds  *	extra checks since ipv6_build_header is used by TCP (which
2581da177e4SLinus Torvalds  *	is for us performance critical)
2591da177e4SLinus Torvalds  */
2601da177e4SLinus Torvalds 
2611da177e4SLinus Torvalds int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev,
2621da177e4SLinus Torvalds 	       struct in6_addr *saddr, struct in6_addr *daddr,
2631da177e4SLinus Torvalds 	       int proto, int len)
2641da177e4SLinus Torvalds {
2651da177e4SLinus Torvalds 	struct ipv6_pinfo *np = inet6_sk(sk);
2661da177e4SLinus Torvalds 	struct ipv6hdr *hdr;
2671da177e4SLinus Torvalds 	int totlen;
2681da177e4SLinus Torvalds 
2691da177e4SLinus Torvalds 	skb->protocol = htons(ETH_P_IPV6);
2701da177e4SLinus Torvalds 	skb->dev = dev;
2711da177e4SLinus Torvalds 
2721da177e4SLinus Torvalds 	totlen = len + sizeof(struct ipv6hdr);
2731da177e4SLinus Torvalds 
27455f79cc0SArnaldo Carvalho de Melo 	skb_reset_network_header(skb);
27555f79cc0SArnaldo Carvalho de Melo 	skb_put(skb, sizeof(struct ipv6hdr));
2760660e03fSArnaldo Carvalho de Melo 	hdr = ipv6_hdr(skb);
2771da177e4SLinus Torvalds 
278ae08e1f0SAl Viro 	*(__be32*)hdr = htonl(0x60000000);
2791da177e4SLinus Torvalds 
2801da177e4SLinus Torvalds 	hdr->payload_len = htons(len);
2811da177e4SLinus Torvalds 	hdr->nexthdr = proto;
2821da177e4SLinus Torvalds 	hdr->hop_limit = np->hop_limit;
2831da177e4SLinus Torvalds 
2841da177e4SLinus Torvalds 	ipv6_addr_copy(&hdr->saddr, saddr);
2851da177e4SLinus Torvalds 	ipv6_addr_copy(&hdr->daddr, daddr);
2861da177e4SLinus Torvalds 
2871da177e4SLinus Torvalds 	return 0;
2881da177e4SLinus Torvalds }
2891da177e4SLinus Torvalds 
2901da177e4SLinus Torvalds static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
2911da177e4SLinus Torvalds {
2921da177e4SLinus Torvalds 	struct ip6_ra_chain *ra;
2931da177e4SLinus Torvalds 	struct sock *last = NULL;
2941da177e4SLinus Torvalds 
2951da177e4SLinus Torvalds 	read_lock(&ip6_ra_lock);
2961da177e4SLinus Torvalds 	for (ra = ip6_ra_chain; ra; ra = ra->next) {
2971da177e4SLinus Torvalds 		struct sock *sk = ra->sk;
2980bd1b59bSAndrew McDonald 		if (sk && ra->sel == sel &&
2990bd1b59bSAndrew McDonald 		    (!sk->sk_bound_dev_if ||
3000bd1b59bSAndrew McDonald 		     sk->sk_bound_dev_if == skb->dev->ifindex)) {
3011da177e4SLinus Torvalds 			if (last) {
3021da177e4SLinus Torvalds 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
3031da177e4SLinus Torvalds 				if (skb2)
3041da177e4SLinus Torvalds 					rawv6_rcv(last, skb2);
3051da177e4SLinus Torvalds 			}
3061da177e4SLinus Torvalds 			last = sk;
3071da177e4SLinus Torvalds 		}
3081da177e4SLinus Torvalds 	}
3091da177e4SLinus Torvalds 
3101da177e4SLinus Torvalds 	if (last) {
3111da177e4SLinus Torvalds 		rawv6_rcv(last, skb);
3121da177e4SLinus Torvalds 		read_unlock(&ip6_ra_lock);
3131da177e4SLinus Torvalds 		return 1;
3141da177e4SLinus Torvalds 	}
3151da177e4SLinus Torvalds 	read_unlock(&ip6_ra_lock);
3161da177e4SLinus Torvalds 	return 0;
3171da177e4SLinus Torvalds }
3181da177e4SLinus Torvalds 
319e21e0b5fSVille Nuorvala static int ip6_forward_proxy_check(struct sk_buff *skb)
320e21e0b5fSVille Nuorvala {
3210660e03fSArnaldo Carvalho de Melo 	struct ipv6hdr *hdr = ipv6_hdr(skb);
322e21e0b5fSVille Nuorvala 	u8 nexthdr = hdr->nexthdr;
323e21e0b5fSVille Nuorvala 	int offset;
324e21e0b5fSVille Nuorvala 
325e21e0b5fSVille Nuorvala 	if (ipv6_ext_hdr(nexthdr)) {
326e21e0b5fSVille Nuorvala 		offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr);
327e21e0b5fSVille Nuorvala 		if (offset < 0)
328e21e0b5fSVille Nuorvala 			return 0;
329e21e0b5fSVille Nuorvala 	} else
330e21e0b5fSVille Nuorvala 		offset = sizeof(struct ipv6hdr);
331e21e0b5fSVille Nuorvala 
332e21e0b5fSVille Nuorvala 	if (nexthdr == IPPROTO_ICMPV6) {
333e21e0b5fSVille Nuorvala 		struct icmp6hdr *icmp6;
334e21e0b5fSVille Nuorvala 
335d56f90a7SArnaldo Carvalho de Melo 		if (!pskb_may_pull(skb, (skb_network_header(skb) +
336d56f90a7SArnaldo Carvalho de Melo 					 offset + 1 - skb->data)))
337e21e0b5fSVille Nuorvala 			return 0;
338e21e0b5fSVille Nuorvala 
339d56f90a7SArnaldo Carvalho de Melo 		icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
340e21e0b5fSVille Nuorvala 
341e21e0b5fSVille Nuorvala 		switch (icmp6->icmp6_type) {
342e21e0b5fSVille Nuorvala 		case NDISC_ROUTER_SOLICITATION:
343e21e0b5fSVille Nuorvala 		case NDISC_ROUTER_ADVERTISEMENT:
344e21e0b5fSVille Nuorvala 		case NDISC_NEIGHBOUR_SOLICITATION:
345e21e0b5fSVille Nuorvala 		case NDISC_NEIGHBOUR_ADVERTISEMENT:
346e21e0b5fSVille Nuorvala 		case NDISC_REDIRECT:
347e21e0b5fSVille Nuorvala 			/* For reaction involving unicast neighbor discovery
348e21e0b5fSVille Nuorvala 			 * message destined to the proxied address, pass it to
349e21e0b5fSVille Nuorvala 			 * input function.
350e21e0b5fSVille Nuorvala 			 */
351e21e0b5fSVille Nuorvala 			return 1;
352e21e0b5fSVille Nuorvala 		default:
353e21e0b5fSVille Nuorvala 			break;
354e21e0b5fSVille Nuorvala 		}
355e21e0b5fSVille Nuorvala 	}
356e21e0b5fSVille Nuorvala 
35774553b09SVille Nuorvala 	/*
35874553b09SVille Nuorvala 	 * The proxying router can't forward traffic sent to a link-local
35974553b09SVille Nuorvala 	 * address, so signal the sender and discard the packet. This
36074553b09SVille Nuorvala 	 * behavior is clarified by the MIPv6 specification.
36174553b09SVille Nuorvala 	 */
36274553b09SVille Nuorvala 	if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
36374553b09SVille Nuorvala 		dst_link_failure(skb);
36474553b09SVille Nuorvala 		return -1;
36574553b09SVille Nuorvala 	}
36674553b09SVille Nuorvala 
367e21e0b5fSVille Nuorvala 	return 0;
368e21e0b5fSVille Nuorvala }
369e21e0b5fSVille Nuorvala 
3701da177e4SLinus Torvalds static inline int ip6_forward_finish(struct sk_buff *skb)
3711da177e4SLinus Torvalds {
3721da177e4SLinus Torvalds 	return dst_output(skb);
3731da177e4SLinus Torvalds }
3741da177e4SLinus Torvalds 
3751da177e4SLinus Torvalds int ip6_forward(struct sk_buff *skb)
3761da177e4SLinus Torvalds {
3771da177e4SLinus Torvalds 	struct dst_entry *dst = skb->dst;
3780660e03fSArnaldo Carvalho de Melo 	struct ipv6hdr *hdr = ipv6_hdr(skb);
3791da177e4SLinus Torvalds 	struct inet6_skb_parm *opt = IP6CB(skb);
3801da177e4SLinus Torvalds 
3811da177e4SLinus Torvalds 	if (ipv6_devconf.forwarding == 0)
3821da177e4SLinus Torvalds 		goto error;
3831da177e4SLinus Torvalds 
3841da177e4SLinus Torvalds 	if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
385a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
3861da177e4SLinus Torvalds 		goto drop;
3871da177e4SLinus Torvalds 	}
3881da177e4SLinus Torvalds 
38935fc92a9SHerbert Xu 	skb_forward_csum(skb);
3901da177e4SLinus Torvalds 
3911da177e4SLinus Torvalds 	/*
3921da177e4SLinus Torvalds 	 *	We DO NOT make any processing on
3931da177e4SLinus Torvalds 	 *	RA packets, pushing them to user level AS IS
3941da177e4SLinus Torvalds 	 *	without ane WARRANTY that application will be able
3951da177e4SLinus Torvalds 	 *	to interpret them. The reason is that we
3961da177e4SLinus Torvalds 	 *	cannot make anything clever here.
3971da177e4SLinus Torvalds 	 *
3981da177e4SLinus Torvalds 	 *	We are not end-node, so that if packet contains
3991da177e4SLinus Torvalds 	 *	AH/ESP, we cannot make anything.
4001da177e4SLinus Torvalds 	 *	Defragmentation also would be mistake, RA packets
4011da177e4SLinus Torvalds 	 *	cannot be fragmented, because there is no warranty
4021da177e4SLinus Torvalds 	 *	that different fragments will go along one path. --ANK
4031da177e4SLinus Torvalds 	 */
4041da177e4SLinus Torvalds 	if (opt->ra) {
405d56f90a7SArnaldo Carvalho de Melo 		u8 *ptr = skb_network_header(skb) + opt->ra;
4061da177e4SLinus Torvalds 		if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
4071da177e4SLinus Torvalds 			return 0;
4081da177e4SLinus Torvalds 	}
4091da177e4SLinus Torvalds 
4101da177e4SLinus Torvalds 	/*
4111da177e4SLinus Torvalds 	 *	check and decrement ttl
4121da177e4SLinus Torvalds 	 */
4131da177e4SLinus Torvalds 	if (hdr->hop_limit <= 1) {
4141da177e4SLinus Torvalds 		/* Force OUTPUT device used as source address */
4151da177e4SLinus Torvalds 		skb->dev = dst->dev;
4161da177e4SLinus Torvalds 		icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
4171da177e4SLinus Torvalds 			    0, skb->dev);
418a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
4191da177e4SLinus Torvalds 
4201da177e4SLinus Torvalds 		kfree_skb(skb);
4211da177e4SLinus Torvalds 		return -ETIMEDOUT;
4221da177e4SLinus Torvalds 	}
4231da177e4SLinus Torvalds 
424fbea49e1SYOSHIFUJI Hideaki 	/* XXX: idev->cnf.proxy_ndp? */
425fbea49e1SYOSHIFUJI Hideaki 	if (ipv6_devconf.proxy_ndp &&
426fbea49e1SYOSHIFUJI Hideaki 	    pneigh_lookup(&nd_tbl, &hdr->daddr, skb->dev, 0)) {
42774553b09SVille Nuorvala 		int proxied = ip6_forward_proxy_check(skb);
42874553b09SVille Nuorvala 		if (proxied > 0)
429e21e0b5fSVille Nuorvala 			return ip6_input(skb);
43074553b09SVille Nuorvala 		else if (proxied < 0) {
431a11d206dSYOSHIFUJI Hideaki 			IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
43274553b09SVille Nuorvala 			goto drop;
43374553b09SVille Nuorvala 		}
434e21e0b5fSVille Nuorvala 	}
435e21e0b5fSVille Nuorvala 
4361da177e4SLinus Torvalds 	if (!xfrm6_route_forward(skb)) {
437a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
4381da177e4SLinus Torvalds 		goto drop;
4391da177e4SLinus Torvalds 	}
4401da177e4SLinus Torvalds 	dst = skb->dst;
4411da177e4SLinus Torvalds 
4421da177e4SLinus Torvalds 	/* IPv6 specs say nothing about it, but it is clear that we cannot
4431da177e4SLinus Torvalds 	   send redirects to source routed frames.
4441da177e4SLinus Torvalds 	 */
4451da177e4SLinus Torvalds 	if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0) {
4461da177e4SLinus Torvalds 		struct in6_addr *target = NULL;
4471da177e4SLinus Torvalds 		struct rt6_info *rt;
4481da177e4SLinus Torvalds 		struct neighbour *n = dst->neighbour;
4491da177e4SLinus Torvalds 
4501da177e4SLinus Torvalds 		/*
4511da177e4SLinus Torvalds 		 *	incoming and outgoing devices are the same
4521da177e4SLinus Torvalds 		 *	send a redirect.
4531da177e4SLinus Torvalds 		 */
4541da177e4SLinus Torvalds 
4551da177e4SLinus Torvalds 		rt = (struct rt6_info *) dst;
4561da177e4SLinus Torvalds 		if ((rt->rt6i_flags & RTF_GATEWAY))
4571da177e4SLinus Torvalds 			target = (struct in6_addr*)&n->primary_key;
4581da177e4SLinus Torvalds 		else
4591da177e4SLinus Torvalds 			target = &hdr->daddr;
4601da177e4SLinus Torvalds 
4611da177e4SLinus Torvalds 		/* Limit redirects both by destination (here)
4621da177e4SLinus Torvalds 		   and by source (inside ndisc_send_redirect)
4631da177e4SLinus Torvalds 		 */
4641da177e4SLinus Torvalds 		if (xrlim_allow(dst, 1*HZ))
4651da177e4SLinus Torvalds 			ndisc_send_redirect(skb, n, target);
4665bb1ab09SDavid L Stevens 	} else {
4675bb1ab09SDavid L Stevens 		int addrtype = ipv6_addr_type(&hdr->saddr);
4685bb1ab09SDavid L Stevens 
4691da177e4SLinus Torvalds 		/* This check is security critical. */
4705bb1ab09SDavid L Stevens 		if (addrtype & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK))
4711da177e4SLinus Torvalds 			goto error;
4725bb1ab09SDavid L Stevens 		if (addrtype & IPV6_ADDR_LINKLOCAL) {
4735bb1ab09SDavid L Stevens 			icmpv6_send(skb, ICMPV6_DEST_UNREACH,
4745bb1ab09SDavid L Stevens 				ICMPV6_NOT_NEIGHBOUR, 0, skb->dev);
4755bb1ab09SDavid L Stevens 			goto error;
4765bb1ab09SDavid L Stevens 		}
4771da177e4SLinus Torvalds 	}
4781da177e4SLinus Torvalds 
4791da177e4SLinus Torvalds 	if (skb->len > dst_mtu(dst)) {
4801da177e4SLinus Torvalds 		/* Again, force OUTPUT device used as source address */
4811da177e4SLinus Torvalds 		skb->dev = dst->dev;
4821da177e4SLinus Torvalds 		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev);
483a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS);
484a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS);
4851da177e4SLinus Torvalds 		kfree_skb(skb);
4861da177e4SLinus Torvalds 		return -EMSGSIZE;
4871da177e4SLinus Torvalds 	}
4881da177e4SLinus Torvalds 
4891da177e4SLinus Torvalds 	if (skb_cow(skb, dst->dev->hard_header_len)) {
490a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS);
4911da177e4SLinus Torvalds 		goto drop;
4921da177e4SLinus Torvalds 	}
4931da177e4SLinus Torvalds 
4940660e03fSArnaldo Carvalho de Melo 	hdr = ipv6_hdr(skb);
4951da177e4SLinus Torvalds 
4961da177e4SLinus Torvalds 	/* Mangling hops number delayed to point after skb COW */
4971da177e4SLinus Torvalds 
4981da177e4SLinus Torvalds 	hdr->hop_limit--;
4991da177e4SLinus Torvalds 
500a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
5011da177e4SLinus Torvalds 	return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish);
5021da177e4SLinus Torvalds 
5031da177e4SLinus Torvalds error:
504a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
5051da177e4SLinus Torvalds drop:
5061da177e4SLinus Torvalds 	kfree_skb(skb);
5071da177e4SLinus Torvalds 	return -EINVAL;
5081da177e4SLinus Torvalds }
5091da177e4SLinus Torvalds 
5101da177e4SLinus Torvalds static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
5111da177e4SLinus Torvalds {
5121da177e4SLinus Torvalds 	to->pkt_type = from->pkt_type;
5131da177e4SLinus Torvalds 	to->priority = from->priority;
5141da177e4SLinus Torvalds 	to->protocol = from->protocol;
5151da177e4SLinus Torvalds 	dst_release(to->dst);
5161da177e4SLinus Torvalds 	to->dst = dst_clone(from->dst);
5171da177e4SLinus Torvalds 	to->dev = from->dev;
51882e91ffeSThomas Graf 	to->mark = from->mark;
5191da177e4SLinus Torvalds 
5201da177e4SLinus Torvalds #ifdef CONFIG_NET_SCHED
5211da177e4SLinus Torvalds 	to->tc_index = from->tc_index;
5221da177e4SLinus Torvalds #endif
523e7ac05f3SYasuyuki Kozakai 	nf_copy(to, from);
524ba9dda3aSJozsef Kadlecsik #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
525ba9dda3aSJozsef Kadlecsik     defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
526ba9dda3aSJozsef Kadlecsik 	to->nf_trace = from->nf_trace;
527ba9dda3aSJozsef Kadlecsik #endif
528984bc16cSJames Morris 	skb_copy_secmark(to, from);
5291da177e4SLinus Torvalds }
5301da177e4SLinus Torvalds 
5311da177e4SLinus Torvalds int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
5321da177e4SLinus Torvalds {
5331da177e4SLinus Torvalds 	u16 offset = sizeof(struct ipv6hdr);
5340660e03fSArnaldo Carvalho de Melo 	struct ipv6_opt_hdr *exthdr =
5350660e03fSArnaldo Carvalho de Melo 				(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
53627a884dcSArnaldo Carvalho de Melo 	unsigned int packet_len = skb->tail - skb->network_header;
5371da177e4SLinus Torvalds 	int found_rhdr = 0;
5380660e03fSArnaldo Carvalho de Melo 	*nexthdr = &ipv6_hdr(skb)->nexthdr;
5391da177e4SLinus Torvalds 
5401da177e4SLinus Torvalds 	while (offset + 1 <= packet_len) {
5411da177e4SLinus Torvalds 
5421da177e4SLinus Torvalds 		switch (**nexthdr) {
5431da177e4SLinus Torvalds 
5441da177e4SLinus Torvalds 		case NEXTHDR_HOP:
54527637df9SMasahide NAKAMURA 			break;
5461da177e4SLinus Torvalds 		case NEXTHDR_ROUTING:
54727637df9SMasahide NAKAMURA 			found_rhdr = 1;
54827637df9SMasahide NAKAMURA 			break;
5491da177e4SLinus Torvalds 		case NEXTHDR_DEST:
55059fbb3a6SMasahide NAKAMURA #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
55127637df9SMasahide NAKAMURA 			if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
55227637df9SMasahide NAKAMURA 				break;
55327637df9SMasahide NAKAMURA #endif
55427637df9SMasahide NAKAMURA 			if (found_rhdr)
55527637df9SMasahide NAKAMURA 				return offset;
5561da177e4SLinus Torvalds 			break;
5571da177e4SLinus Torvalds 		default :
5581da177e4SLinus Torvalds 			return offset;
5591da177e4SLinus Torvalds 		}
56027637df9SMasahide NAKAMURA 
56127637df9SMasahide NAKAMURA 		offset += ipv6_optlen(exthdr);
56227637df9SMasahide NAKAMURA 		*nexthdr = &exthdr->nexthdr;
563d56f90a7SArnaldo Carvalho de Melo 		exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
564d56f90a7SArnaldo Carvalho de Melo 						 offset);
5651da177e4SLinus Torvalds 	}
5661da177e4SLinus Torvalds 
5671da177e4SLinus Torvalds 	return offset;
5681da177e4SLinus Torvalds }
569b59f45d0SHerbert Xu EXPORT_SYMBOL_GPL(ip6_find_1stfragopt);
5701da177e4SLinus Torvalds 
5711da177e4SLinus Torvalds static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
5721da177e4SLinus Torvalds {
5731da177e4SLinus Torvalds 	struct net_device *dev;
5741da177e4SLinus Torvalds 	struct sk_buff *frag;
5751da177e4SLinus Torvalds 	struct rt6_info *rt = (struct rt6_info*)skb->dst;
576d91675f9SYOSHIFUJI Hideaki 	struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
5771da177e4SLinus Torvalds 	struct ipv6hdr *tmp_hdr;
5781da177e4SLinus Torvalds 	struct frag_hdr *fh;
5791da177e4SLinus Torvalds 	unsigned int mtu, hlen, left, len;
580ae08e1f0SAl Viro 	__be32 frag_id = 0;
5811da177e4SLinus Torvalds 	int ptr, offset = 0, err=0;
5821da177e4SLinus Torvalds 	u8 *prevhdr, nexthdr = 0;
5831da177e4SLinus Torvalds 
5841da177e4SLinus Torvalds 	dev = rt->u.dst.dev;
5851da177e4SLinus Torvalds 	hlen = ip6_find_1stfragopt(skb, &prevhdr);
5861da177e4SLinus Torvalds 	nexthdr = *prevhdr;
5871da177e4SLinus Torvalds 
588628a5c56SJohn Heffner 	mtu = ip6_skb_dst_mtu(skb);
589b881ef76SJohn Heffner 
590b881ef76SJohn Heffner 	/* We must not fragment if the socket is set to force MTU discovery
591b881ef76SJohn Heffner 	 * or if the skb it not generated by a local socket.  (This last
592b881ef76SJohn Heffner 	 * check should be redundant, but it's free.)
593b881ef76SJohn Heffner 	 */
594b881ef76SJohn Heffner 	if (!np || np->pmtudisc >= IPV6_PMTUDISC_DO) {
595b881ef76SJohn Heffner 		skb->dev = skb->dst->dev;
596b881ef76SJohn Heffner 		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
597b881ef76SJohn Heffner 		IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
598b881ef76SJohn Heffner 		kfree_skb(skb);
599b881ef76SJohn Heffner 		return -EMSGSIZE;
600b881ef76SJohn Heffner 	}
601b881ef76SJohn Heffner 
602d91675f9SYOSHIFUJI Hideaki 	if (np && np->frag_size < mtu) {
603d91675f9SYOSHIFUJI Hideaki 		if (np->frag_size)
604d91675f9SYOSHIFUJI Hideaki 			mtu = np->frag_size;
605d91675f9SYOSHIFUJI Hideaki 	}
606d91675f9SYOSHIFUJI Hideaki 	mtu -= hlen + sizeof(struct frag_hdr);
6071da177e4SLinus Torvalds 
6081da177e4SLinus Torvalds 	if (skb_shinfo(skb)->frag_list) {
6091da177e4SLinus Torvalds 		int first_len = skb_pagelen(skb);
6101da177e4SLinus Torvalds 
6111da177e4SLinus Torvalds 		if (first_len - hlen > mtu ||
6121da177e4SLinus Torvalds 		    ((first_len - hlen) & 7) ||
6131da177e4SLinus Torvalds 		    skb_cloned(skb))
6141da177e4SLinus Torvalds 			goto slow_path;
6151da177e4SLinus Torvalds 
6161da177e4SLinus Torvalds 		for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
6171da177e4SLinus Torvalds 			/* Correct geometry. */
6181da177e4SLinus Torvalds 			if (frag->len > mtu ||
6191da177e4SLinus Torvalds 			    ((frag->len & 7) && frag->next) ||
6201da177e4SLinus Torvalds 			    skb_headroom(frag) < hlen)
6211da177e4SLinus Torvalds 			    goto slow_path;
6221da177e4SLinus Torvalds 
6231da177e4SLinus Torvalds 			/* Partially cloned skb? */
6241da177e4SLinus Torvalds 			if (skb_shared(frag))
6251da177e4SLinus Torvalds 				goto slow_path;
6262fdba6b0SHerbert Xu 
6272fdba6b0SHerbert Xu 			BUG_ON(frag->sk);
6282fdba6b0SHerbert Xu 			if (skb->sk) {
6292fdba6b0SHerbert Xu 				sock_hold(skb->sk);
6302fdba6b0SHerbert Xu 				frag->sk = skb->sk;
6312fdba6b0SHerbert Xu 				frag->destructor = sock_wfree;
6322fdba6b0SHerbert Xu 				skb->truesize -= frag->truesize;
6332fdba6b0SHerbert Xu 			}
6341da177e4SLinus Torvalds 		}
6351da177e4SLinus Torvalds 
6361da177e4SLinus Torvalds 		err = 0;
6371da177e4SLinus Torvalds 		offset = 0;
6381da177e4SLinus Torvalds 		frag = skb_shinfo(skb)->frag_list;
6391da177e4SLinus Torvalds 		skb_shinfo(skb)->frag_list = NULL;
6401da177e4SLinus Torvalds 		/* BUILD HEADER */
6411da177e4SLinus Torvalds 
6429a217a1cSYOSHIFUJI Hideaki 		*prevhdr = NEXTHDR_FRAGMENT;
643d56f90a7SArnaldo Carvalho de Melo 		tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
6441da177e4SLinus Torvalds 		if (!tmp_hdr) {
645a11d206dSYOSHIFUJI Hideaki 			IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
6461da177e4SLinus Torvalds 			return -ENOMEM;
6471da177e4SLinus Torvalds 		}
6481da177e4SLinus Torvalds 
6491da177e4SLinus Torvalds 		__skb_pull(skb, hlen);
6501da177e4SLinus Torvalds 		fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
651e2d1bca7SArnaldo Carvalho de Melo 		__skb_push(skb, hlen);
652e2d1bca7SArnaldo Carvalho de Melo 		skb_reset_network_header(skb);
653d56f90a7SArnaldo Carvalho de Melo 		memcpy(skb_network_header(skb), tmp_hdr, hlen);
6541da177e4SLinus Torvalds 
6551da177e4SLinus Torvalds 		ipv6_select_ident(skb, fh);
6561da177e4SLinus Torvalds 		fh->nexthdr = nexthdr;
6571da177e4SLinus Torvalds 		fh->reserved = 0;
6581da177e4SLinus Torvalds 		fh->frag_off = htons(IP6_MF);
6591da177e4SLinus Torvalds 		frag_id = fh->identification;
6601da177e4SLinus Torvalds 
6611da177e4SLinus Torvalds 		first_len = skb_pagelen(skb);
6621da177e4SLinus Torvalds 		skb->data_len = first_len - skb_headlen(skb);
6631da177e4SLinus Torvalds 		skb->len = first_len;
6640660e03fSArnaldo Carvalho de Melo 		ipv6_hdr(skb)->payload_len = htons(first_len -
6650660e03fSArnaldo Carvalho de Melo 						   sizeof(struct ipv6hdr));
6661da177e4SLinus Torvalds 
667a11d206dSYOSHIFUJI Hideaki 		dst_hold(&rt->u.dst);
6681da177e4SLinus Torvalds 
6691da177e4SLinus Torvalds 		for (;;) {
6701da177e4SLinus Torvalds 			/* Prepare header of the next frame,
6711da177e4SLinus Torvalds 			 * before previous one went down. */
6721da177e4SLinus Torvalds 			if (frag) {
6731da177e4SLinus Torvalds 				frag->ip_summed = CHECKSUM_NONE;
674badff6d0SArnaldo Carvalho de Melo 				skb_reset_transport_header(frag);
6751da177e4SLinus Torvalds 				fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
676e2d1bca7SArnaldo Carvalho de Melo 				__skb_push(frag, hlen);
677e2d1bca7SArnaldo Carvalho de Melo 				skb_reset_network_header(frag);
678d56f90a7SArnaldo Carvalho de Melo 				memcpy(skb_network_header(frag), tmp_hdr,
679d56f90a7SArnaldo Carvalho de Melo 				       hlen);
6801da177e4SLinus Torvalds 				offset += skb->len - hlen - sizeof(struct frag_hdr);
6811da177e4SLinus Torvalds 				fh->nexthdr = nexthdr;
6821da177e4SLinus Torvalds 				fh->reserved = 0;
6831da177e4SLinus Torvalds 				fh->frag_off = htons(offset);
6841da177e4SLinus Torvalds 				if (frag->next != NULL)
6851da177e4SLinus Torvalds 					fh->frag_off |= htons(IP6_MF);
6861da177e4SLinus Torvalds 				fh->identification = frag_id;
6870660e03fSArnaldo Carvalho de Melo 				ipv6_hdr(frag)->payload_len =
6880660e03fSArnaldo Carvalho de Melo 						htons(frag->len -
6890660e03fSArnaldo Carvalho de Melo 						      sizeof(struct ipv6hdr));
6901da177e4SLinus Torvalds 				ip6_copy_metadata(frag, skb);
6911da177e4SLinus Torvalds 			}
6921da177e4SLinus Torvalds 
6931da177e4SLinus Torvalds 			err = output(skb);
694dafee490SWei Dong 			if(!err)
695a11d206dSYOSHIFUJI Hideaki 				IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGCREATES);
696dafee490SWei Dong 
6971da177e4SLinus Torvalds 			if (err || !frag)
6981da177e4SLinus Torvalds 				break;
6991da177e4SLinus Torvalds 
7001da177e4SLinus Torvalds 			skb = frag;
7011da177e4SLinus Torvalds 			frag = skb->next;
7021da177e4SLinus Torvalds 			skb->next = NULL;
7031da177e4SLinus Torvalds 		}
7041da177e4SLinus Torvalds 
7051da177e4SLinus Torvalds 		kfree(tmp_hdr);
7061da177e4SLinus Torvalds 
7071da177e4SLinus Torvalds 		if (err == 0) {
708a11d206dSYOSHIFUJI Hideaki 			IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGOKS);
709a11d206dSYOSHIFUJI Hideaki 			dst_release(&rt->u.dst);
7101da177e4SLinus Torvalds 			return 0;
7111da177e4SLinus Torvalds 		}
7121da177e4SLinus Torvalds 
7131da177e4SLinus Torvalds 		while (frag) {
7141da177e4SLinus Torvalds 			skb = frag->next;
7151da177e4SLinus Torvalds 			kfree_skb(frag);
7161da177e4SLinus Torvalds 			frag = skb;
7171da177e4SLinus Torvalds 		}
7181da177e4SLinus Torvalds 
719a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGFAILS);
720a11d206dSYOSHIFUJI Hideaki 		dst_release(&rt->u.dst);
7211da177e4SLinus Torvalds 		return err;
7221da177e4SLinus Torvalds 	}
7231da177e4SLinus Torvalds 
7241da177e4SLinus Torvalds slow_path:
7251da177e4SLinus Torvalds 	left = skb->len - hlen;		/* Space per frame */
7261da177e4SLinus Torvalds 	ptr = hlen;			/* Where to start from */
7271da177e4SLinus Torvalds 
7281da177e4SLinus Torvalds 	/*
7291da177e4SLinus Torvalds 	 *	Fragment the datagram.
7301da177e4SLinus Torvalds 	 */
7311da177e4SLinus Torvalds 
7321da177e4SLinus Torvalds 	*prevhdr = NEXTHDR_FRAGMENT;
7331da177e4SLinus Torvalds 
7341da177e4SLinus Torvalds 	/*
7351da177e4SLinus Torvalds 	 *	Keep copying data until we run out.
7361da177e4SLinus Torvalds 	 */
7371da177e4SLinus Torvalds 	while(left > 0)	{
7381da177e4SLinus Torvalds 		len = left;
7391da177e4SLinus Torvalds 		/* IF: it doesn't fit, use 'mtu' - the data space left */
7401da177e4SLinus Torvalds 		if (len > mtu)
7411da177e4SLinus Torvalds 			len = mtu;
7421da177e4SLinus Torvalds 		/* IF: we are not sending upto and including the packet end
7431da177e4SLinus Torvalds 		   then align the next start on an eight byte boundary */
7441da177e4SLinus Torvalds 		if (len < left)	{
7451da177e4SLinus Torvalds 			len &= ~7;
7461da177e4SLinus Torvalds 		}
7471da177e4SLinus Torvalds 		/*
7481da177e4SLinus Torvalds 		 *	Allocate buffer.
7491da177e4SLinus Torvalds 		 */
7501da177e4SLinus Torvalds 
7511da177e4SLinus Torvalds 		if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) {
75264ce2073SPatrick McHardy 			NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
753a11d206dSYOSHIFUJI Hideaki 			IP6_INC_STATS(ip6_dst_idev(skb->dst),
754a11d206dSYOSHIFUJI Hideaki 				      IPSTATS_MIB_FRAGFAILS);
7551da177e4SLinus Torvalds 			err = -ENOMEM;
7561da177e4SLinus Torvalds 			goto fail;
7571da177e4SLinus Torvalds 		}
7581da177e4SLinus Torvalds 
7591da177e4SLinus Torvalds 		/*
7601da177e4SLinus Torvalds 		 *	Set up data on packet
7611da177e4SLinus Torvalds 		 */
7621da177e4SLinus Torvalds 
7631da177e4SLinus Torvalds 		ip6_copy_metadata(frag, skb);
7641da177e4SLinus Torvalds 		skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev));
7651da177e4SLinus Torvalds 		skb_put(frag, len + hlen + sizeof(struct frag_hdr));
766c1d2bbe1SArnaldo Carvalho de Melo 		skb_reset_network_header(frag);
767badff6d0SArnaldo Carvalho de Melo 		fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
768b0e380b1SArnaldo Carvalho de Melo 		frag->transport_header = (frag->network_header + hlen +
769b0e380b1SArnaldo Carvalho de Melo 					  sizeof(struct frag_hdr));
7701da177e4SLinus Torvalds 
7711da177e4SLinus Torvalds 		/*
7721da177e4SLinus Torvalds 		 *	Charge the memory for the fragment to any owner
7731da177e4SLinus Torvalds 		 *	it might possess
7741da177e4SLinus Torvalds 		 */
7751da177e4SLinus Torvalds 		if (skb->sk)
7761da177e4SLinus Torvalds 			skb_set_owner_w(frag, skb->sk);
7771da177e4SLinus Torvalds 
7781da177e4SLinus Torvalds 		/*
7791da177e4SLinus Torvalds 		 *	Copy the packet header into the new buffer.
7801da177e4SLinus Torvalds 		 */
781d626f62bSArnaldo Carvalho de Melo 		skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
7821da177e4SLinus Torvalds 
7831da177e4SLinus Torvalds 		/*
7841da177e4SLinus Torvalds 		 *	Build fragment header.
7851da177e4SLinus Torvalds 		 */
7861da177e4SLinus Torvalds 		fh->nexthdr = nexthdr;
7871da177e4SLinus Torvalds 		fh->reserved = 0;
788f36d6ab1SYan Zheng 		if (!frag_id) {
7891da177e4SLinus Torvalds 			ipv6_select_ident(skb, fh);
7901da177e4SLinus Torvalds 			frag_id = fh->identification;
7911da177e4SLinus Torvalds 		} else
7921da177e4SLinus Torvalds 			fh->identification = frag_id;
7931da177e4SLinus Torvalds 
7941da177e4SLinus Torvalds 		/*
7951da177e4SLinus Torvalds 		 *	Copy a block of the IP datagram.
7961da177e4SLinus Torvalds 		 */
7978984e41dSWei Yongjun 		if (skb_copy_bits(skb, ptr, skb_transport_header(frag), len))
7981da177e4SLinus Torvalds 			BUG();
7991da177e4SLinus Torvalds 		left -= len;
8001da177e4SLinus Torvalds 
8011da177e4SLinus Torvalds 		fh->frag_off = htons(offset);
8021da177e4SLinus Torvalds 		if (left > 0)
8031da177e4SLinus Torvalds 			fh->frag_off |= htons(IP6_MF);
8040660e03fSArnaldo Carvalho de Melo 		ipv6_hdr(frag)->payload_len = htons(frag->len -
8050660e03fSArnaldo Carvalho de Melo 						    sizeof(struct ipv6hdr));
8061da177e4SLinus Torvalds 
8071da177e4SLinus Torvalds 		ptr += len;
8081da177e4SLinus Torvalds 		offset += len;
8091da177e4SLinus Torvalds 
8101da177e4SLinus Torvalds 		/*
8111da177e4SLinus Torvalds 		 *	Put this fragment into the sending queue.
8121da177e4SLinus Torvalds 		 */
8131da177e4SLinus Torvalds 		err = output(frag);
8141da177e4SLinus Torvalds 		if (err)
8151da177e4SLinus Torvalds 			goto fail;
816dafee490SWei Dong 
817a11d206dSYOSHIFUJI Hideaki 		IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGCREATES);
8181da177e4SLinus Torvalds 	}
819a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS(ip6_dst_idev(skb->dst),
820a11d206dSYOSHIFUJI Hideaki 		      IPSTATS_MIB_FRAGOKS);
8211da177e4SLinus Torvalds 	kfree_skb(skb);
8221da177e4SLinus Torvalds 	return err;
8231da177e4SLinus Torvalds 
8241da177e4SLinus Torvalds fail:
825a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS(ip6_dst_idev(skb->dst),
826a11d206dSYOSHIFUJI Hideaki 		      IPSTATS_MIB_FRAGFAILS);
8271da177e4SLinus Torvalds 	kfree_skb(skb);
8281da177e4SLinus Torvalds 	return err;
8291da177e4SLinus Torvalds }
8301da177e4SLinus Torvalds 
831cf6b1982SYOSHIFUJI Hideaki static inline int ip6_rt_check(struct rt6key *rt_key,
832cf6b1982SYOSHIFUJI Hideaki 			       struct in6_addr *fl_addr,
833cf6b1982SYOSHIFUJI Hideaki 			       struct in6_addr *addr_cache)
834cf6b1982SYOSHIFUJI Hideaki {
835cf6b1982SYOSHIFUJI Hideaki 	return ((rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
836cf6b1982SYOSHIFUJI Hideaki 		(addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache)));
837cf6b1982SYOSHIFUJI Hideaki }
838cf6b1982SYOSHIFUJI Hideaki 
839497c615aSHerbert Xu static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
840497c615aSHerbert Xu 					  struct dst_entry *dst,
841497c615aSHerbert Xu 					  struct flowi *fl)
8421da177e4SLinus Torvalds {
8431da177e4SLinus Torvalds 	struct ipv6_pinfo *np = inet6_sk(sk);
844497c615aSHerbert Xu 	struct rt6_info *rt = (struct rt6_info *)dst;
8451da177e4SLinus Torvalds 
846497c615aSHerbert Xu 	if (!dst)
847497c615aSHerbert Xu 		goto out;
8481da177e4SLinus Torvalds 
8491da177e4SLinus Torvalds 	/* Yes, checking route validity in not connected
850d76e60a5SDavid S. Miller 	 * case is not very simple. Take into account,
851d76e60a5SDavid S. Miller 	 * that we do not support routing by source, TOS,
852d76e60a5SDavid S. Miller 	 * and MSG_DONTROUTE 		--ANK (980726)
853d76e60a5SDavid S. Miller 	 *
854cf6b1982SYOSHIFUJI Hideaki 	 * 1. ip6_rt_check(): If route was host route,
855cf6b1982SYOSHIFUJI Hideaki 	 *    check that cached destination is current.
856d76e60a5SDavid S. Miller 	 *    If it is network route, we still may
857d76e60a5SDavid S. Miller 	 *    check its validity using saved pointer
858d76e60a5SDavid S. Miller 	 *    to the last used address: daddr_cache.
859d76e60a5SDavid S. Miller 	 *    We do not want to save whole address now,
860d76e60a5SDavid S. Miller 	 *    (because main consumer of this service
861d76e60a5SDavid S. Miller 	 *    is tcp, which has not this problem),
862d76e60a5SDavid S. Miller 	 *    so that the last trick works only on connected
863d76e60a5SDavid S. Miller 	 *    sockets.
864d76e60a5SDavid S. Miller 	 * 2. oif also should be the same.
8651da177e4SLinus Torvalds 	 */
866cf6b1982SYOSHIFUJI Hideaki 	if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) ||
8678e1ef0a9SYOSHIFUJI Hideaki #ifdef CONFIG_IPV6_SUBTREES
8688e1ef0a9SYOSHIFUJI Hideaki 	    ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) ||
8698e1ef0a9SYOSHIFUJI Hideaki #endif
870cf6b1982SYOSHIFUJI Hideaki 	    (fl->oif && fl->oif != dst->dev->ifindex)) {
871497c615aSHerbert Xu 		dst_release(dst);
872497c615aSHerbert Xu 		dst = NULL;
8731da177e4SLinus Torvalds 	}
874497c615aSHerbert Xu 
875497c615aSHerbert Xu out:
876497c615aSHerbert Xu 	return dst;
8771da177e4SLinus Torvalds }
878497c615aSHerbert Xu 
879497c615aSHerbert Xu static int ip6_dst_lookup_tail(struct sock *sk,
880497c615aSHerbert Xu 			       struct dst_entry **dst, struct flowi *fl)
881497c615aSHerbert Xu {
882497c615aSHerbert Xu 	int err;
8831da177e4SLinus Torvalds 
8841da177e4SLinus Torvalds 	if (*dst == NULL)
8851da177e4SLinus Torvalds 		*dst = ip6_route_output(sk, fl);
8861da177e4SLinus Torvalds 
8871da177e4SLinus Torvalds 	if ((err = (*dst)->error))
8881da177e4SLinus Torvalds 		goto out_err_release;
8891da177e4SLinus Torvalds 
8901da177e4SLinus Torvalds 	if (ipv6_addr_any(&fl->fl6_src)) {
8911da177e4SLinus Torvalds 		err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src);
89244456d37SOlaf Hering 		if (err)
8931da177e4SLinus Torvalds 			goto out_err_release;
8941da177e4SLinus Torvalds 	}
8951da177e4SLinus Torvalds 
89695c385b4SNeil Horman #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
89795c385b4SNeil Horman 		/*
89895c385b4SNeil Horman 		 * Here if the dst entry we've looked up
89995c385b4SNeil Horman 		 * has a neighbour entry that is in the INCOMPLETE
90095c385b4SNeil Horman 		 * state and the src address from the flow is
90195c385b4SNeil Horman 		 * marked as OPTIMISTIC, we release the found
90295c385b4SNeil Horman 		 * dst entry and replace it instead with the
90395c385b4SNeil Horman 		 * dst entry of the nexthop router
90495c385b4SNeil Horman 		 */
90595c385b4SNeil Horman 		if (!((*dst)->neighbour->nud_state & NUD_VALID)) {
90695c385b4SNeil Horman 			struct inet6_ifaddr *ifp;
90795c385b4SNeil Horman 			struct flowi fl_gw;
90895c385b4SNeil Horman 			int redirect;
90995c385b4SNeil Horman 
91095c385b4SNeil Horman 			ifp = ipv6_get_ifaddr(&fl->fl6_src, (*dst)->dev, 1);
91195c385b4SNeil Horman 
91295c385b4SNeil Horman 			redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
91395c385b4SNeil Horman 			if (ifp)
91495c385b4SNeil Horman 				in6_ifa_put(ifp);
91595c385b4SNeil Horman 
91695c385b4SNeil Horman 			if (redirect) {
91795c385b4SNeil Horman 				/*
91895c385b4SNeil Horman 				 * We need to get the dst entry for the
91995c385b4SNeil Horman 				 * default router instead
92095c385b4SNeil Horman 				 */
92195c385b4SNeil Horman 				dst_release(*dst);
92295c385b4SNeil Horman 				memcpy(&fl_gw, fl, sizeof(struct flowi));
92395c385b4SNeil Horman 				memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr));
92495c385b4SNeil Horman 				*dst = ip6_route_output(sk, &fl_gw);
92595c385b4SNeil Horman 				if ((err = (*dst)->error))
92695c385b4SNeil Horman 					goto out_err_release;
92795c385b4SNeil Horman 			}
92895c385b4SNeil Horman 		}
92995c385b4SNeil Horman #endif
93095c385b4SNeil Horman 
9311da177e4SLinus Torvalds 	return 0;
9321da177e4SLinus Torvalds 
9331da177e4SLinus Torvalds out_err_release:
9341da177e4SLinus Torvalds 	dst_release(*dst);
9351da177e4SLinus Torvalds 	*dst = NULL;
9361da177e4SLinus Torvalds 	return err;
9371da177e4SLinus Torvalds }
93834a0b3cdSAdrian Bunk 
939497c615aSHerbert Xu /**
940497c615aSHerbert Xu  *	ip6_dst_lookup - perform route lookup on flow
941497c615aSHerbert Xu  *	@sk: socket which provides route info
942497c615aSHerbert Xu  *	@dst: pointer to dst_entry * for result
943497c615aSHerbert Xu  *	@fl: flow to lookup
944497c615aSHerbert Xu  *
945497c615aSHerbert Xu  *	This function performs a route lookup on the given flow.
946497c615aSHerbert Xu  *
947497c615aSHerbert Xu  *	It returns zero on success, or a standard errno code on error.
948497c615aSHerbert Xu  */
949497c615aSHerbert Xu int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
950497c615aSHerbert Xu {
951497c615aSHerbert Xu 	*dst = NULL;
952497c615aSHerbert Xu 	return ip6_dst_lookup_tail(sk, dst, fl);
953497c615aSHerbert Xu }
9543cf3dc6cSArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(ip6_dst_lookup);
9553cf3dc6cSArnaldo Carvalho de Melo 
956497c615aSHerbert Xu /**
957497c615aSHerbert Xu  *	ip6_sk_dst_lookup - perform socket cached route lookup on flow
958497c615aSHerbert Xu  *	@sk: socket which provides the dst cache and route info
959497c615aSHerbert Xu  *	@dst: pointer to dst_entry * for result
960497c615aSHerbert Xu  *	@fl: flow to lookup
961497c615aSHerbert Xu  *
962497c615aSHerbert Xu  *	This function performs a route lookup on the given flow with the
963497c615aSHerbert Xu  *	possibility of using the cached route in the socket if it is valid.
964497c615aSHerbert Xu  *	It will take the socket dst lock when operating on the dst cache.
965497c615aSHerbert Xu  *	As a result, this function can only be used in process context.
966497c615aSHerbert Xu  *
967497c615aSHerbert Xu  *	It returns zero on success, or a standard errno code on error.
968497c615aSHerbert Xu  */
969497c615aSHerbert Xu int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
970497c615aSHerbert Xu {
971497c615aSHerbert Xu 	*dst = NULL;
972497c615aSHerbert Xu 	if (sk) {
973497c615aSHerbert Xu 		*dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
974497c615aSHerbert Xu 		*dst = ip6_sk_dst_check(sk, *dst, fl);
975497c615aSHerbert Xu 	}
976497c615aSHerbert Xu 
977497c615aSHerbert Xu 	return ip6_dst_lookup_tail(sk, dst, fl);
978497c615aSHerbert Xu }
979497c615aSHerbert Xu EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup);
980497c615aSHerbert Xu 
98134a0b3cdSAdrian Bunk static inline int ip6_ufo_append_data(struct sock *sk,
982e89e9cf5SAnanda Raju 			int getfrag(void *from, char *to, int offset, int len,
983e89e9cf5SAnanda Raju 			int odd, struct sk_buff *skb),
984e89e9cf5SAnanda Raju 			void *from, int length, int hh_len, int fragheaderlen,
985e89e9cf5SAnanda Raju 			int transhdrlen, int mtu,unsigned int flags)
986e89e9cf5SAnanda Raju 
987e89e9cf5SAnanda Raju {
988e89e9cf5SAnanda Raju 	struct sk_buff *skb;
989e89e9cf5SAnanda Raju 	int err;
990e89e9cf5SAnanda Raju 
991e89e9cf5SAnanda Raju 	/* There is support for UDP large send offload by network
992e89e9cf5SAnanda Raju 	 * device, so create one single skb packet containing complete
993e89e9cf5SAnanda Raju 	 * udp datagram
994e89e9cf5SAnanda Raju 	 */
995e89e9cf5SAnanda Raju 	if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
996e89e9cf5SAnanda Raju 		skb = sock_alloc_send_skb(sk,
997e89e9cf5SAnanda Raju 			hh_len + fragheaderlen + transhdrlen + 20,
998e89e9cf5SAnanda Raju 			(flags & MSG_DONTWAIT), &err);
999e89e9cf5SAnanda Raju 		if (skb == NULL)
1000e89e9cf5SAnanda Raju 			return -ENOMEM;
1001e89e9cf5SAnanda Raju 
1002e89e9cf5SAnanda Raju 		/* reserve space for Hardware header */
1003e89e9cf5SAnanda Raju 		skb_reserve(skb, hh_len);
1004e89e9cf5SAnanda Raju 
1005e89e9cf5SAnanda Raju 		/* create space for UDP/IP header */
1006e89e9cf5SAnanda Raju 		skb_put(skb,fragheaderlen + transhdrlen);
1007e89e9cf5SAnanda Raju 
1008e89e9cf5SAnanda Raju 		/* initialize network header pointer */
1009c1d2bbe1SArnaldo Carvalho de Melo 		skb_reset_network_header(skb);
1010e89e9cf5SAnanda Raju 
1011e89e9cf5SAnanda Raju 		/* initialize protocol header pointer */
1012b0e380b1SArnaldo Carvalho de Melo 		skb->transport_header = skb->network_header + fragheaderlen;
1013e89e9cf5SAnanda Raju 
101484fa7933SPatrick McHardy 		skb->ip_summed = CHECKSUM_PARTIAL;
1015e89e9cf5SAnanda Raju 		skb->csum = 0;
1016e89e9cf5SAnanda Raju 		sk->sk_sndmsg_off = 0;
1017e89e9cf5SAnanda Raju 	}
1018e89e9cf5SAnanda Raju 
1019e89e9cf5SAnanda Raju 	err = skb_append_datato_frags(sk,skb, getfrag, from,
1020e89e9cf5SAnanda Raju 				      (length - transhdrlen));
1021e89e9cf5SAnanda Raju 	if (!err) {
1022e89e9cf5SAnanda Raju 		struct frag_hdr fhdr;
1023e89e9cf5SAnanda Raju 
1024e89e9cf5SAnanda Raju 		/* specify the length of each IP datagram fragment*/
10257967168cSHerbert Xu 		skb_shinfo(skb)->gso_size = mtu - fragheaderlen -
1026e89e9cf5SAnanda Raju 					    sizeof(struct frag_hdr);
1027f83ef8c0SHerbert Xu 		skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
1028e89e9cf5SAnanda Raju 		ipv6_select_ident(skb, &fhdr);
1029e89e9cf5SAnanda Raju 		skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
1030e89e9cf5SAnanda Raju 		__skb_queue_tail(&sk->sk_write_queue, skb);
1031e89e9cf5SAnanda Raju 
1032e89e9cf5SAnanda Raju 		return 0;
1033e89e9cf5SAnanda Raju 	}
1034e89e9cf5SAnanda Raju 	/* There is not enough support do UPD LSO,
1035e89e9cf5SAnanda Raju 	 * so follow normal path
1036e89e9cf5SAnanda Raju 	 */
1037e89e9cf5SAnanda Raju 	kfree_skb(skb);
1038e89e9cf5SAnanda Raju 
1039e89e9cf5SAnanda Raju 	return err;
1040e89e9cf5SAnanda Raju }
10411da177e4SLinus Torvalds 
104241a1f8eaSYOSHIFUJI Hideaki int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
104341a1f8eaSYOSHIFUJI Hideaki 	int offset, int len, int odd, struct sk_buff *skb),
10441da177e4SLinus Torvalds 	void *from, int length, int transhdrlen,
104541a1f8eaSYOSHIFUJI Hideaki 	int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl,
104641a1f8eaSYOSHIFUJI Hideaki 	struct rt6_info *rt, unsigned int flags)
10471da177e4SLinus Torvalds {
10481da177e4SLinus Torvalds 	struct inet_sock *inet = inet_sk(sk);
10491da177e4SLinus Torvalds 	struct ipv6_pinfo *np = inet6_sk(sk);
10501da177e4SLinus Torvalds 	struct sk_buff *skb;
10511da177e4SLinus Torvalds 	unsigned int maxfraglen, fragheaderlen;
10521da177e4SLinus Torvalds 	int exthdrlen;
10531da177e4SLinus Torvalds 	int hh_len;
10541da177e4SLinus Torvalds 	int mtu;
10551da177e4SLinus Torvalds 	int copy;
10561da177e4SLinus Torvalds 	int err;
10571da177e4SLinus Torvalds 	int offset = 0;
10581da177e4SLinus Torvalds 	int csummode = CHECKSUM_NONE;
10591da177e4SLinus Torvalds 
10601da177e4SLinus Torvalds 	if (flags&MSG_PROBE)
10611da177e4SLinus Torvalds 		return 0;
10621da177e4SLinus Torvalds 	if (skb_queue_empty(&sk->sk_write_queue)) {
10631da177e4SLinus Torvalds 		/*
10641da177e4SLinus Torvalds 		 * setup for corking
10651da177e4SLinus Torvalds 		 */
10661da177e4SLinus Torvalds 		if (opt) {
10671da177e4SLinus Torvalds 			if (np->cork.opt == NULL) {
10681da177e4SLinus Torvalds 				np->cork.opt = kmalloc(opt->tot_len,
10691da177e4SLinus Torvalds 						       sk->sk_allocation);
10701da177e4SLinus Torvalds 				if (unlikely(np->cork.opt == NULL))
10711da177e4SLinus Torvalds 					return -ENOBUFS;
10721da177e4SLinus Torvalds 			} else if (np->cork.opt->tot_len < opt->tot_len) {
10731da177e4SLinus Torvalds 				printk(KERN_DEBUG "ip6_append_data: invalid option length\n");
10741da177e4SLinus Torvalds 				return -EINVAL;
10751da177e4SLinus Torvalds 			}
10761da177e4SLinus Torvalds 			memcpy(np->cork.opt, opt, opt->tot_len);
10771da177e4SLinus Torvalds 			inet->cork.flags |= IPCORK_OPT;
10781da177e4SLinus Torvalds 			/* need source address above miyazawa*/
10791da177e4SLinus Torvalds 		}
10801da177e4SLinus Torvalds 		dst_hold(&rt->u.dst);
10811da177e4SLinus Torvalds 		np->cork.rt = rt;
10821da177e4SLinus Torvalds 		inet->cork.fl = *fl;
10831da177e4SLinus Torvalds 		np->cork.hop_limit = hlimit;
108441a1f8eaSYOSHIFUJI Hideaki 		np->cork.tclass = tclass;
1085628a5c56SJohn Heffner 		mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
1086628a5c56SJohn Heffner 		      rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path);
1087c7503609SDave Jones 		if (np->frag_size < mtu) {
1088d91675f9SYOSHIFUJI Hideaki 			if (np->frag_size)
1089d91675f9SYOSHIFUJI Hideaki 				mtu = np->frag_size;
1090d91675f9SYOSHIFUJI Hideaki 		}
1091d91675f9SYOSHIFUJI Hideaki 		inet->cork.fragsize = mtu;
10921da177e4SLinus Torvalds 		if (dst_allfrag(rt->u.dst.path))
10931da177e4SLinus Torvalds 			inet->cork.flags |= IPCORK_ALLFRAG;
10941da177e4SLinus Torvalds 		inet->cork.length = 0;
10951da177e4SLinus Torvalds 		sk->sk_sndmsg_page = NULL;
10961da177e4SLinus Torvalds 		sk->sk_sndmsg_off = 0;
10971da177e4SLinus Torvalds 		exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0);
10981da177e4SLinus Torvalds 		length += exthdrlen;
10991da177e4SLinus Torvalds 		transhdrlen += exthdrlen;
11001da177e4SLinus Torvalds 	} else {
11011da177e4SLinus Torvalds 		rt = np->cork.rt;
11021da177e4SLinus Torvalds 		fl = &inet->cork.fl;
11031da177e4SLinus Torvalds 		if (inet->cork.flags & IPCORK_OPT)
11041da177e4SLinus Torvalds 			opt = np->cork.opt;
11051da177e4SLinus Torvalds 		transhdrlen = 0;
11061da177e4SLinus Torvalds 		exthdrlen = 0;
11071da177e4SLinus Torvalds 		mtu = inet->cork.fragsize;
11081da177e4SLinus Torvalds 	}
11091da177e4SLinus Torvalds 
11101da177e4SLinus Torvalds 	hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
11111da177e4SLinus Torvalds 
11121b5c2299SMasahide NAKAMURA 	fragheaderlen = sizeof(struct ipv6hdr) + rt->u.dst.nfheader_len + (opt ? opt->opt_nflen : 0);
11131da177e4SLinus Torvalds 	maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
11141da177e4SLinus Torvalds 
11151da177e4SLinus Torvalds 	if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
11161da177e4SLinus Torvalds 		if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
11171da177e4SLinus Torvalds 			ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen);
11181da177e4SLinus Torvalds 			return -EMSGSIZE;
11191da177e4SLinus Torvalds 		}
11201da177e4SLinus Torvalds 	}
11211da177e4SLinus Torvalds 
11221da177e4SLinus Torvalds 	/*
11231da177e4SLinus Torvalds 	 * Let's try using as much space as possible.
11241da177e4SLinus Torvalds 	 * Use MTU if total length of the message fits into the MTU.
11251da177e4SLinus Torvalds 	 * Otherwise, we need to reserve fragment header and
11261da177e4SLinus Torvalds 	 * fragment alignment (= 8-15 octects, in total).
11271da177e4SLinus Torvalds 	 *
11281da177e4SLinus Torvalds 	 * Note that we may need to "move" the data from the tail of
11291da177e4SLinus Torvalds 	 * of the buffer to the new fragment when we split
11301da177e4SLinus Torvalds 	 * the message.
11311da177e4SLinus Torvalds 	 *
11321da177e4SLinus Torvalds 	 * FIXME: It may be fragmented into multiple chunks
11331da177e4SLinus Torvalds 	 *        at once if non-fragmentable extension headers
11341da177e4SLinus Torvalds 	 *        are too large.
11351da177e4SLinus Torvalds 	 * --yoshfuji
11361da177e4SLinus Torvalds 	 */
11371da177e4SLinus Torvalds 
11381da177e4SLinus Torvalds 	inet->cork.length += length;
1139e89e9cf5SAnanda Raju 	if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) &&
1140e89e9cf5SAnanda Raju 	    (rt->u.dst.dev->features & NETIF_F_UFO)) {
1141e89e9cf5SAnanda Raju 
1142baa829d8SPatrick McHardy 		err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len,
1143baa829d8SPatrick McHardy 					  fragheaderlen, transhdrlen, mtu,
1144baa829d8SPatrick McHardy 					  flags);
1145baa829d8SPatrick McHardy 		if (err)
1146e89e9cf5SAnanda Raju 			goto error;
1147e89e9cf5SAnanda Raju 		return 0;
1148e89e9cf5SAnanda Raju 	}
11491da177e4SLinus Torvalds 
11501da177e4SLinus Torvalds 	if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
11511da177e4SLinus Torvalds 		goto alloc_new_skb;
11521da177e4SLinus Torvalds 
11531da177e4SLinus Torvalds 	while (length > 0) {
11541da177e4SLinus Torvalds 		/* Check if the remaining data fits into current packet. */
11551da177e4SLinus Torvalds 		copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
11561da177e4SLinus Torvalds 		if (copy < length)
11571da177e4SLinus Torvalds 			copy = maxfraglen - skb->len;
11581da177e4SLinus Torvalds 
11591da177e4SLinus Torvalds 		if (copy <= 0) {
11601da177e4SLinus Torvalds 			char *data;
11611da177e4SLinus Torvalds 			unsigned int datalen;
11621da177e4SLinus Torvalds 			unsigned int fraglen;
11631da177e4SLinus Torvalds 			unsigned int fraggap;
11641da177e4SLinus Torvalds 			unsigned int alloclen;
11651da177e4SLinus Torvalds 			struct sk_buff *skb_prev;
11661da177e4SLinus Torvalds alloc_new_skb:
11671da177e4SLinus Torvalds 			skb_prev = skb;
11681da177e4SLinus Torvalds 
11691da177e4SLinus Torvalds 			/* There's no room in the current skb */
11701da177e4SLinus Torvalds 			if (skb_prev)
11711da177e4SLinus Torvalds 				fraggap = skb_prev->len - maxfraglen;
11721da177e4SLinus Torvalds 			else
11731da177e4SLinus Torvalds 				fraggap = 0;
11741da177e4SLinus Torvalds 
11751da177e4SLinus Torvalds 			/*
11761da177e4SLinus Torvalds 			 * If remaining data exceeds the mtu,
11771da177e4SLinus Torvalds 			 * we know we need more fragment(s).
11781da177e4SLinus Torvalds 			 */
11791da177e4SLinus Torvalds 			datalen = length + fraggap;
11801da177e4SLinus Torvalds 			if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
11811da177e4SLinus Torvalds 				datalen = maxfraglen - fragheaderlen;
11821da177e4SLinus Torvalds 
11831da177e4SLinus Torvalds 			fraglen = datalen + fragheaderlen;
11841da177e4SLinus Torvalds 			if ((flags & MSG_MORE) &&
11851da177e4SLinus Torvalds 			    !(rt->u.dst.dev->features&NETIF_F_SG))
11861da177e4SLinus Torvalds 				alloclen = mtu;
11871da177e4SLinus Torvalds 			else
11881da177e4SLinus Torvalds 				alloclen = datalen + fragheaderlen;
11891da177e4SLinus Torvalds 
11901da177e4SLinus Torvalds 			/*
11911da177e4SLinus Torvalds 			 * The last fragment gets additional space at tail.
11921da177e4SLinus Torvalds 			 * Note: we overallocate on fragments with MSG_MODE
11931da177e4SLinus Torvalds 			 * because we have no idea if we're the last one.
11941da177e4SLinus Torvalds 			 */
11951da177e4SLinus Torvalds 			if (datalen == length + fraggap)
11961da177e4SLinus Torvalds 				alloclen += rt->u.dst.trailer_len;
11971da177e4SLinus Torvalds 
11981da177e4SLinus Torvalds 			/*
11991da177e4SLinus Torvalds 			 * We just reserve space for fragment header.
12001da177e4SLinus Torvalds 			 * Note: this may be overallocation if the message
12011da177e4SLinus Torvalds 			 * (without MSG_MORE) fits into the MTU.
12021da177e4SLinus Torvalds 			 */
12031da177e4SLinus Torvalds 			alloclen += sizeof(struct frag_hdr);
12041da177e4SLinus Torvalds 
12051da177e4SLinus Torvalds 			if (transhdrlen) {
12061da177e4SLinus Torvalds 				skb = sock_alloc_send_skb(sk,
12071da177e4SLinus Torvalds 						alloclen + hh_len,
12081da177e4SLinus Torvalds 						(flags & MSG_DONTWAIT), &err);
12091da177e4SLinus Torvalds 			} else {
12101da177e4SLinus Torvalds 				skb = NULL;
12111da177e4SLinus Torvalds 				if (atomic_read(&sk->sk_wmem_alloc) <=
12121da177e4SLinus Torvalds 				    2 * sk->sk_sndbuf)
12131da177e4SLinus Torvalds 					skb = sock_wmalloc(sk,
12141da177e4SLinus Torvalds 							   alloclen + hh_len, 1,
12151da177e4SLinus Torvalds 							   sk->sk_allocation);
12161da177e4SLinus Torvalds 				if (unlikely(skb == NULL))
12171da177e4SLinus Torvalds 					err = -ENOBUFS;
12181da177e4SLinus Torvalds 			}
12191da177e4SLinus Torvalds 			if (skb == NULL)
12201da177e4SLinus Torvalds 				goto error;
12211da177e4SLinus Torvalds 			/*
12221da177e4SLinus Torvalds 			 *	Fill in the control structures
12231da177e4SLinus Torvalds 			 */
12241da177e4SLinus Torvalds 			skb->ip_summed = csummode;
12251da177e4SLinus Torvalds 			skb->csum = 0;
12261da177e4SLinus Torvalds 			/* reserve for fragmentation */
12271da177e4SLinus Torvalds 			skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
12281da177e4SLinus Torvalds 
12291da177e4SLinus Torvalds 			/*
12301da177e4SLinus Torvalds 			 *	Find where to start putting bytes
12311da177e4SLinus Torvalds 			 */
12321da177e4SLinus Torvalds 			data = skb_put(skb, fraglen);
1233c14d2450SArnaldo Carvalho de Melo 			skb_set_network_header(skb, exthdrlen);
12341da177e4SLinus Torvalds 			data += fragheaderlen;
1235b0e380b1SArnaldo Carvalho de Melo 			skb->transport_header = (skb->network_header +
1236b0e380b1SArnaldo Carvalho de Melo 						 fragheaderlen);
12371da177e4SLinus Torvalds 			if (fraggap) {
12381da177e4SLinus Torvalds 				skb->csum = skb_copy_and_csum_bits(
12391da177e4SLinus Torvalds 					skb_prev, maxfraglen,
12401da177e4SLinus Torvalds 					data + transhdrlen, fraggap, 0);
12411da177e4SLinus Torvalds 				skb_prev->csum = csum_sub(skb_prev->csum,
12421da177e4SLinus Torvalds 							  skb->csum);
12431da177e4SLinus Torvalds 				data += fraggap;
1244e9fa4f7bSHerbert Xu 				pskb_trim_unique(skb_prev, maxfraglen);
12451da177e4SLinus Torvalds 			}
12461da177e4SLinus Torvalds 			copy = datalen - transhdrlen - fraggap;
12471da177e4SLinus Torvalds 			if (copy < 0) {
12481da177e4SLinus Torvalds 				err = -EINVAL;
12491da177e4SLinus Torvalds 				kfree_skb(skb);
12501da177e4SLinus Torvalds 				goto error;
12511da177e4SLinus Torvalds 			} else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
12521da177e4SLinus Torvalds 				err = -EFAULT;
12531da177e4SLinus Torvalds 				kfree_skb(skb);
12541da177e4SLinus Torvalds 				goto error;
12551da177e4SLinus Torvalds 			}
12561da177e4SLinus Torvalds 
12571da177e4SLinus Torvalds 			offset += copy;
12581da177e4SLinus Torvalds 			length -= datalen - fraggap;
12591da177e4SLinus Torvalds 			transhdrlen = 0;
12601da177e4SLinus Torvalds 			exthdrlen = 0;
12611da177e4SLinus Torvalds 			csummode = CHECKSUM_NONE;
12621da177e4SLinus Torvalds 
12631da177e4SLinus Torvalds 			/*
12641da177e4SLinus Torvalds 			 * Put the packet on the pending queue
12651da177e4SLinus Torvalds 			 */
12661da177e4SLinus Torvalds 			__skb_queue_tail(&sk->sk_write_queue, skb);
12671da177e4SLinus Torvalds 			continue;
12681da177e4SLinus Torvalds 		}
12691da177e4SLinus Torvalds 
12701da177e4SLinus Torvalds 		if (copy > length)
12711da177e4SLinus Torvalds 			copy = length;
12721da177e4SLinus Torvalds 
12731da177e4SLinus Torvalds 		if (!(rt->u.dst.dev->features&NETIF_F_SG)) {
12741da177e4SLinus Torvalds 			unsigned int off;
12751da177e4SLinus Torvalds 
12761da177e4SLinus Torvalds 			off = skb->len;
12771da177e4SLinus Torvalds 			if (getfrag(from, skb_put(skb, copy),
12781da177e4SLinus Torvalds 						offset, copy, off, skb) < 0) {
12791da177e4SLinus Torvalds 				__skb_trim(skb, off);
12801da177e4SLinus Torvalds 				err = -EFAULT;
12811da177e4SLinus Torvalds 				goto error;
12821da177e4SLinus Torvalds 			}
12831da177e4SLinus Torvalds 		} else {
12841da177e4SLinus Torvalds 			int i = skb_shinfo(skb)->nr_frags;
12851da177e4SLinus Torvalds 			skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1];
12861da177e4SLinus Torvalds 			struct page *page = sk->sk_sndmsg_page;
12871da177e4SLinus Torvalds 			int off = sk->sk_sndmsg_off;
12881da177e4SLinus Torvalds 			unsigned int left;
12891da177e4SLinus Torvalds 
12901da177e4SLinus Torvalds 			if (page && (left = PAGE_SIZE - off) > 0) {
12911da177e4SLinus Torvalds 				if (copy >= left)
12921da177e4SLinus Torvalds 					copy = left;
12931da177e4SLinus Torvalds 				if (page != frag->page) {
12941da177e4SLinus Torvalds 					if (i == MAX_SKB_FRAGS) {
12951da177e4SLinus Torvalds 						err = -EMSGSIZE;
12961da177e4SLinus Torvalds 						goto error;
12971da177e4SLinus Torvalds 					}
12981da177e4SLinus Torvalds 					get_page(page);
12991da177e4SLinus Torvalds 					skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
13001da177e4SLinus Torvalds 					frag = &skb_shinfo(skb)->frags[i];
13011da177e4SLinus Torvalds 				}
13021da177e4SLinus Torvalds 			} else if(i < MAX_SKB_FRAGS) {
13031da177e4SLinus Torvalds 				if (copy > PAGE_SIZE)
13041da177e4SLinus Torvalds 					copy = PAGE_SIZE;
13051da177e4SLinus Torvalds 				page = alloc_pages(sk->sk_allocation, 0);
13061da177e4SLinus Torvalds 				if (page == NULL) {
13071da177e4SLinus Torvalds 					err = -ENOMEM;
13081da177e4SLinus Torvalds 					goto error;
13091da177e4SLinus Torvalds 				}
13101da177e4SLinus Torvalds 				sk->sk_sndmsg_page = page;
13111da177e4SLinus Torvalds 				sk->sk_sndmsg_off = 0;
13121da177e4SLinus Torvalds 
13131da177e4SLinus Torvalds 				skb_fill_page_desc(skb, i, page, 0, 0);
13141da177e4SLinus Torvalds 				frag = &skb_shinfo(skb)->frags[i];
13151da177e4SLinus Torvalds 				skb->truesize += PAGE_SIZE;
13161da177e4SLinus Torvalds 				atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc);
13171da177e4SLinus Torvalds 			} else {
13181da177e4SLinus Torvalds 				err = -EMSGSIZE;
13191da177e4SLinus Torvalds 				goto error;
13201da177e4SLinus Torvalds 			}
13211da177e4SLinus Torvalds 			if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) {
13221da177e4SLinus Torvalds 				err = -EFAULT;
13231da177e4SLinus Torvalds 				goto error;
13241da177e4SLinus Torvalds 			}
13251da177e4SLinus Torvalds 			sk->sk_sndmsg_off += copy;
13261da177e4SLinus Torvalds 			frag->size += copy;
13271da177e4SLinus Torvalds 			skb->len += copy;
13281da177e4SLinus Torvalds 			skb->data_len += copy;
13291da177e4SLinus Torvalds 		}
13301da177e4SLinus Torvalds 		offset += copy;
13311da177e4SLinus Torvalds 		length -= copy;
13321da177e4SLinus Torvalds 	}
13331da177e4SLinus Torvalds 	return 0;
13341da177e4SLinus Torvalds error:
13351da177e4SLinus Torvalds 	inet->cork.length -= length;
1336a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
13371da177e4SLinus Torvalds 	return err;
13381da177e4SLinus Torvalds }
13391da177e4SLinus Torvalds 
13401da177e4SLinus Torvalds int ip6_push_pending_frames(struct sock *sk)
13411da177e4SLinus Torvalds {
13421da177e4SLinus Torvalds 	struct sk_buff *skb, *tmp_skb;
13431da177e4SLinus Torvalds 	struct sk_buff **tail_skb;
13441da177e4SLinus Torvalds 	struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
13451da177e4SLinus Torvalds 	struct inet_sock *inet = inet_sk(sk);
13461da177e4SLinus Torvalds 	struct ipv6_pinfo *np = inet6_sk(sk);
13471da177e4SLinus Torvalds 	struct ipv6hdr *hdr;
13481da177e4SLinus Torvalds 	struct ipv6_txoptions *opt = np->cork.opt;
13491da177e4SLinus Torvalds 	struct rt6_info *rt = np->cork.rt;
13501da177e4SLinus Torvalds 	struct flowi *fl = &inet->cork.fl;
13511da177e4SLinus Torvalds 	unsigned char proto = fl->proto;
13521da177e4SLinus Torvalds 	int err = 0;
13531da177e4SLinus Torvalds 
13541da177e4SLinus Torvalds 	if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL)
13551da177e4SLinus Torvalds 		goto out;
13561da177e4SLinus Torvalds 	tail_skb = &(skb_shinfo(skb)->frag_list);
13571da177e4SLinus Torvalds 
13581da177e4SLinus Torvalds 	/* move skb->data to ip header from ext header */
1359d56f90a7SArnaldo Carvalho de Melo 	if (skb->data < skb_network_header(skb))
1360bbe735e4SArnaldo Carvalho de Melo 		__skb_pull(skb, skb_network_offset(skb));
13611da177e4SLinus Torvalds 	while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
1362cfe1fc77SArnaldo Carvalho de Melo 		__skb_pull(tmp_skb, skb_network_header_len(skb));
13631da177e4SLinus Torvalds 		*tail_skb = tmp_skb;
13641da177e4SLinus Torvalds 		tail_skb = &(tmp_skb->next);
13651da177e4SLinus Torvalds 		skb->len += tmp_skb->len;
13661da177e4SLinus Torvalds 		skb->data_len += tmp_skb->len;
13671da177e4SLinus Torvalds 		skb->truesize += tmp_skb->truesize;
13681da177e4SLinus Torvalds 		__sock_put(tmp_skb->sk);
13691da177e4SLinus Torvalds 		tmp_skb->destructor = NULL;
13701da177e4SLinus Torvalds 		tmp_skb->sk = NULL;
13711da177e4SLinus Torvalds 	}
13721da177e4SLinus Torvalds 
13731da177e4SLinus Torvalds 	ipv6_addr_copy(final_dst, &fl->fl6_dst);
1374cfe1fc77SArnaldo Carvalho de Melo 	__skb_pull(skb, skb_network_header_len(skb));
13751da177e4SLinus Torvalds 	if (opt && opt->opt_flen)
13761da177e4SLinus Torvalds 		ipv6_push_frag_opts(skb, opt, &proto);
13771da177e4SLinus Torvalds 	if (opt && opt->opt_nflen)
13781da177e4SLinus Torvalds 		ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
13791da177e4SLinus Torvalds 
1380e2d1bca7SArnaldo Carvalho de Melo 	skb_push(skb, sizeof(struct ipv6hdr));
1381e2d1bca7SArnaldo Carvalho de Melo 	skb_reset_network_header(skb);
13820660e03fSArnaldo Carvalho de Melo 	hdr = ipv6_hdr(skb);
13831da177e4SLinus Torvalds 
138490bcaf7bSAl Viro 	*(__be32*)hdr = fl->fl6_flowlabel |
138541a1f8eaSYOSHIFUJI Hideaki 		     htonl(0x60000000 | ((int)np->cork.tclass << 20));
13861da177e4SLinus Torvalds 
13871da177e4SLinus Torvalds 	if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN)
13881da177e4SLinus Torvalds 		hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
13891da177e4SLinus Torvalds 	else
13901da177e4SLinus Torvalds 		hdr->payload_len = 0;
13911da177e4SLinus Torvalds 	hdr->hop_limit = np->cork.hop_limit;
13921da177e4SLinus Torvalds 	hdr->nexthdr = proto;
13931da177e4SLinus Torvalds 	ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
13941da177e4SLinus Torvalds 	ipv6_addr_copy(&hdr->daddr, final_dst);
13951da177e4SLinus Torvalds 
1396a2c2064fSPatrick McHardy 	skb->priority = sk->sk_priority;
1397a2c2064fSPatrick McHardy 
13981da177e4SLinus Torvalds 	skb->dst = dst_clone(&rt->u.dst);
1399a11d206dSYOSHIFUJI Hideaki 	IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS);
14001da177e4SLinus Torvalds 	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output);
14011da177e4SLinus Torvalds 	if (err) {
14021da177e4SLinus Torvalds 		if (err > 0)
14033320da89SHerbert Xu 			err = np->recverr ? net_xmit_errno(err) : 0;
14041da177e4SLinus Torvalds 		if (err)
14051da177e4SLinus Torvalds 			goto error;
14061da177e4SLinus Torvalds 	}
14071da177e4SLinus Torvalds 
14081da177e4SLinus Torvalds out:
14091da177e4SLinus Torvalds 	inet->cork.flags &= ~IPCORK_OPT;
14101da177e4SLinus Torvalds 	kfree(np->cork.opt);
14111da177e4SLinus Torvalds 	np->cork.opt = NULL;
14121da177e4SLinus Torvalds 	if (np->cork.rt) {
14131da177e4SLinus Torvalds 		dst_release(&np->cork.rt->u.dst);
14141da177e4SLinus Torvalds 		np->cork.rt = NULL;
14151da177e4SLinus Torvalds 		inet->cork.flags &= ~IPCORK_ALLFRAG;
14161da177e4SLinus Torvalds 	}
14171da177e4SLinus Torvalds 	memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
14181da177e4SLinus Torvalds 	return err;
14191da177e4SLinus Torvalds error:
14201da177e4SLinus Torvalds 	goto out;
14211da177e4SLinus Torvalds }
14221da177e4SLinus Torvalds 
14231da177e4SLinus Torvalds void ip6_flush_pending_frames(struct sock *sk)
14241da177e4SLinus Torvalds {
14251da177e4SLinus Torvalds 	struct inet_sock *inet = inet_sk(sk);
14261da177e4SLinus Torvalds 	struct ipv6_pinfo *np = inet6_sk(sk);
14271da177e4SLinus Torvalds 	struct sk_buff *skb;
14281da177e4SLinus Torvalds 
14291da177e4SLinus Torvalds 	while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
1430*e1f52208SYOSHIFUJI Hideaki 		if (skb->dst)
1431a11d206dSYOSHIFUJI Hideaki 			IP6_INC_STATS(ip6_dst_idev(skb->dst),
1432a11d206dSYOSHIFUJI Hideaki 				      IPSTATS_MIB_OUTDISCARDS);
14331da177e4SLinus Torvalds 		kfree_skb(skb);
14341da177e4SLinus Torvalds 	}
14351da177e4SLinus Torvalds 
14361da177e4SLinus Torvalds 	inet->cork.flags &= ~IPCORK_OPT;
14371da177e4SLinus Torvalds 
14381da177e4SLinus Torvalds 	kfree(np->cork.opt);
14391da177e4SLinus Torvalds 	np->cork.opt = NULL;
14401da177e4SLinus Torvalds 	if (np->cork.rt) {
14411da177e4SLinus Torvalds 		dst_release(&np->cork.rt->u.dst);
14421da177e4SLinus Torvalds 		np->cork.rt = NULL;
14431da177e4SLinus Torvalds 		inet->cork.flags &= ~IPCORK_ALLFRAG;
14441da177e4SLinus Torvalds 	}
14451da177e4SLinus Torvalds 	memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
14461da177e4SLinus Torvalds }
1447