Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1197 insertions, 0 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
new file mode 100644
index 00000000000..49208ba7509
--- /dev/null
+++ b/net/ipv6/ip6_output.c
@@ -0,0 +1,1197 @@
+/*
+ *	IPv6 output functions
+ *	Linux INET6 implementation 
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>	
+ *
+ *	$Id: ip6_output.c,v 1.34 2002/02/01 22:01:04 davem Exp $
+ *
+ *	Based on linux/net/ipv4/ip_output.c
+ *
+ *	This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ *
+ *	Changes:
+ *	A.N.Kuznetsov	:	airthmetics in fragmentation.
+ *				extension headers are implemented.
+ *				route changes now work.
+ *				ip6_forward does not confuse sniffers.
+ *				etc.
+ *
+ *      H. von Brand    :       Added missing #include <linux/string.h>
+ *	Imran Patel	: 	frag id should be in NBO
+ *      Kazunori MIYAZAWA @USAGI
+ *			:       add ip6_append_data and related functions
+ *				for datagram xmit
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/in6.h>
+#include <linux/tcp.h>
+#include <linux/route.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/ndisc.h>
+#include <net/protocol.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/rawv6.h>
+#include <net/icmp.h>
+#include <net/xfrm.h>
+#include <net/checksum.h>
+
+static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
+
+static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr)
+{
+	static u32 ipv6_fragmentation_id = 1;
+	static DEFINE_SPINLOCK(ip6_id_lock);
+
+	spin_lock_bh(&ip6_id_lock);
+	fhdr->identification = htonl(ipv6_fragmentation_id);
+	if (++ipv6_fragmentation_id == 0)
+		ipv6_fragmentation_id = 1;
+	spin_unlock_bh(&ip6_id_lock);
+}
+
+static inline int ip6_output_finish(struct sk_buff *skb)
+{
+
+	struct dst_entry *dst = skb->dst;
+	struct hh_cache *hh = dst->hh;
+
+	if (hh) {
+		int hh_alen;
+
+		read_lock_bh(&hh->hh_lock);
+		hh_alen = HH_DATA_ALIGN(hh->hh_len);
+		memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
+		read_unlock_bh(&hh->hh_lock);
+	        skb_push(skb, hh->hh_len);
+		return hh->hh_output(skb);
+	} else if (dst->neighbour)
+		return dst->neighbour->output(skb);
+
+	IP6_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
+	kfree_skb(skb);
+	return -EINVAL;
+
+}
+
+/* dev_loopback_xmit for use with netfilter. */
+static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
+{
+	newskb->mac.raw = newskb->data;
+	__skb_pull(newskb, newskb->nh.raw - newskb->data);
+	newskb->pkt_type = PACKET_LOOPBACK;
+	newskb->ip_summed = CHECKSUM_UNNECESSARY;
+	BUG_TRAP(newskb->dst);
+
+	netif_rx(newskb);
+	return 0;
+}
+
+
+static int ip6_output2(struct sk_buff *skb)
+{
+	struct dst_entry *dst = skb->dst;
+	struct net_device *dev = dst->dev;
+
+	skb->protocol = htons(ETH_P_IPV6);
+	skb->dev = dev;
+
+	if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr)) {
+		struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL;
+
+		if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) &&
+		    ipv6_chk_mcast_addr(dev, &skb->nh.ipv6h->daddr,
+				&skb->nh.ipv6h->saddr)) {
+			struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
+
+			/* Do not check for IFF_ALLMULTI; multicast routing
+			   is not supported in any case.
+			 */
+			if (newskb)
+				NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL,
+					newskb->dev,
+					ip6_dev_loopback_xmit);
+
+			if (skb->nh.ipv6h->hop_limit == 0) {
+				IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
+				kfree_skb(skb);
+				return 0;
+			}
+		}
+
+		IP6_INC_STATS(IPSTATS_MIB_OUTMCASTPKTS);
+	}
+
+	return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish);
+}
+
+int ip6_output(struct sk_buff *skb)
+{
+	if (skb->len > dst_mtu(skb->dst) || dst_allfrag(skb->dst))
+		return ip6_fragment(skb, ip6_output2);
+	else
+		return ip6_output2(skb);
+}
+
+#ifdef CONFIG_NETFILTER
+int ip6_route_me_harder(struct sk_buff *skb)
+{
+	struct ipv6hdr *iph = skb->nh.ipv6h;
+	struct dst_entry *dst;
+	struct flowi fl = {
+		.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
+		.nl_u =
+		{ .ip6_u =
+		  { .daddr = iph->daddr,
+		    .saddr = iph->saddr, } },
+		.proto = iph->nexthdr,
+	};
+
+	dst = ip6_route_output(skb->sk, &fl);
+
+	if (dst->error) {
+		IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
+		LIMIT_NETDEBUG(
+			printk(KERN_DEBUG "ip6_route_me_harder: No more route.\n"));
+		dst_release(dst);
+		return -EINVAL;
+	}
+
+	/* Drop old route. */
+	dst_release(skb->dst);
+
+	skb->dst = dst;
+	return 0;
+}
+#endif
+
+static inline int ip6_maybe_reroute(struct sk_buff *skb)
+{
+#ifdef CONFIG_NETFILTER
+	if (skb->nfcache & NFC_ALTERED){
+		if (ip6_route_me_harder(skb) != 0){
+			kfree_skb(skb);
+			return -EINVAL;
+		}
+	}
+#endif /* CONFIG_NETFILTER */
+	return dst_output(skb);
+}
+
+/*
+ *	xmit an sk_buff (used by TCP)
+ */
+
+int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
+	     struct ipv6_txoptions *opt, int ipfragok)
+{
+	struct ipv6_pinfo *np = sk ? inet6_sk(sk) : NULL;
+	struct in6_addr *first_hop = &fl->fl6_dst;
+	struct dst_entry *dst = skb->dst;
+	struct ipv6hdr *hdr;
+	u8  proto = fl->proto;
+	int seg_len = skb->len;
+	int hlimit;
+	u32 mtu;
+
+	if (opt) {
+		int head_room;
+
+		/* First: exthdrs may take lots of space (~8K for now)
+		   MAX_HEADER is not enough.
+		 */
+		head_room = opt->opt_nflen + opt->opt_flen;
+		seg_len += head_room;
+		head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
+
+		if (skb_headroom(skb) < head_room) {
+			struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
+			kfree_skb(skb);
+			skb = skb2;
+			if (skb == NULL) {	
+				IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
+				return -ENOBUFS;
+			}
+			if (sk)
+				skb_set_owner_w(skb, sk);
+		}
+		if (opt->opt_flen)
+			ipv6_push_frag_opts(skb, opt, &proto);
+		if (opt->opt_nflen)
+			ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
+	}
+
+	hdr = skb->nh.ipv6h = (struct ipv6hdr*)skb_push(skb, sizeof(struct ipv6hdr));
+
+	/*
+	 *	Fill in the IPv6 header
+	 */
+
+	*(u32*)hdr = htonl(0x60000000) | fl->fl6_flowlabel;
+	hlimit = -1;
+	if (np)
+		hlimit = np->hop_limit;
+	if (hlimit < 0)
+		hlimit = dst_metric(dst, RTAX_HOPLIMIT);
+	if (hlimit < 0)
+		hlimit = ipv6_get_hoplimit(dst->dev);
+
+	hdr->payload_len = htons(seg_len);
+	hdr->nexthdr = proto;
+	hdr->hop_limit = hlimit;
+
+	ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
+	ipv6_addr_copy(&hdr->daddr, first_hop);
+
+	mtu = dst_mtu(dst);
+	if ((skb->len <= mtu) || ipfragok) {
+		IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
+		return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, ip6_maybe_reroute);
+	}
+
+	if (net_ratelimit())
+		printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
+	skb->dev = dst->dev;
+	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
+	IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
+	kfree_skb(skb);
+	return -EMSGSIZE;
+}
+
+/*
+ *	To avoid extra problems ND packets are send through this
+ *	routine. It's code duplication but I really want to avoid
+ *	extra checks since ipv6_build_header is used by TCP (which
+ *	is for us performance critical)
+ */
+
+int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev,
+	       struct in6_addr *saddr, struct in6_addr *daddr,
+	       int proto, int len)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct ipv6hdr *hdr;
+	int totlen;
+
+	skb->protocol = htons(ETH_P_IPV6);
+	skb->dev = dev;
+
+	totlen = len + sizeof(struct ipv6hdr);
+
+	hdr = (struct ipv6hdr *) skb_put(skb, sizeof(struct ipv6hdr));
+	skb->nh.ipv6h = hdr;
+
+	*(u32*)hdr = htonl(0x60000000);
+
+	hdr->payload_len = htons(len);
+	hdr->nexthdr = proto;
+	hdr->hop_limit = np->hop_limit;
+
+	ipv6_addr_copy(&hdr->saddr, saddr);
+	ipv6_addr_copy(&hdr->daddr, daddr);
+
+	return 0;
+}
+
+static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
+{
+	struct ip6_ra_chain *ra;
+	struct sock *last = NULL;
+
+	read_lock(&ip6_ra_lock);
+	for (ra = ip6_ra_chain; ra; ra = ra->next) {
+		struct sock *sk = ra->sk;
+		if (sk && ra->sel == sel) {
+			if (last) {
+				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
+				if (skb2)
+					rawv6_rcv(last, skb2);
+			}
+			last = sk;
+		}
+	}
+
+	if (last) {
+		rawv6_rcv(last, skb);
+		read_unlock(&ip6_ra_lock);
+		return 1;
+	}
+	read_unlock(&ip6_ra_lock);
+	return 0;
+}
+
+static inline int ip6_forward_finish(struct sk_buff *skb)
+{
+	return dst_output(skb);
+}
+
+int ip6_forward(struct sk_buff *skb)
+{
+	struct dst_entry *dst = skb->dst;
+	struct ipv6hdr *hdr = skb->nh.ipv6h;
+	struct inet6_skb_parm *opt = IP6CB(skb);
+	
+	if (ipv6_devconf.forwarding == 0)
+		goto error;
+
+	if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
+		IP6_INC_STATS(IPSTATS_MIB_INDISCARDS);
+		goto drop;
+	}
+
+	skb->ip_summed = CHECKSUM_NONE;
+
+	/*
+	 *	We DO NOT make any processing on
+	 *	RA packets, pushing them to user level AS IS
+	 *	without ane WARRANTY that application will be able
+	 *	to interpret them. The reason is that we
+	 *	cannot make anything clever here.
+	 *
+	 *	We are not end-node, so that if packet contains
+	 *	AH/ESP, we cannot make anything.
+	 *	Defragmentation also would be mistake, RA packets
+	 *	cannot be fragmented, because there is no warranty
+	 *	that different fragments will go along one path. --ANK
+	 */
+	if (opt->ra) {
+		u8 *ptr = skb->nh.raw + opt->ra;
+		if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
+			return 0;
+	}
+
+	/*
+	 *	check and decrement ttl
+	 */
+	if (hdr->hop_limit <= 1) {
+		/* Force OUTPUT device used as source address */
+		skb->dev = dst->dev;
+		icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
+			    0, skb->dev);
+
+		kfree_skb(skb);
+		return -ETIMEDOUT;
+	}
+
+	if (!xfrm6_route_forward(skb)) {
+		IP6_INC_STATS(IPSTATS_MIB_INDISCARDS);
+		goto drop;
+	}
+	dst = skb->dst;
+
+	/* IPv6 specs say nothing about it, but it is clear that we cannot
+	   send redirects to source routed frames.
+	 */
+	if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0) {
+		struct in6_addr *target = NULL;
+		struct rt6_info *rt;
+		struct neighbour *n = dst->neighbour;
+
+		/*
+		 *	incoming and outgoing devices are the same
+		 *	send a redirect.
+		 */
+
+		rt = (struct rt6_info *) dst;
+		if ((rt->rt6i_flags & RTF_GATEWAY))
+			target = (struct in6_addr*)&n->primary_key;
+		else
+			target = &hdr->daddr;
+
+		/* Limit redirects both by destination (here)
+		   and by source (inside ndisc_send_redirect)
+		 */
+		if (xrlim_allow(dst, 1*HZ))
+			ndisc_send_redirect(skb, n, target);
+	} else if (ipv6_addr_type(&hdr->saddr)&(IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK
+						|IPV6_ADDR_LINKLOCAL)) {
+		/* This check is security critical. */
+		goto error;
+	}
+
+	if (skb->len > dst_mtu(dst)) {
+		/* Again, force OUTPUT device used as source address */
+		skb->dev = dst->dev;
+		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev);
+		IP6_INC_STATS_BH(IPSTATS_MIB_INTOOBIGERRORS);
+		IP6_INC_STATS_BH(IPSTATS_MIB_FRAGFAILS);
+		kfree_skb(skb);
+		return -EMSGSIZE;
+	}
+
+	if (skb_cow(skb, dst->dev->hard_header_len)) {
+		IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
+		goto drop;
+	}
+
+	hdr = skb->nh.ipv6h;
+
+	/* Mangling hops number delayed to point after skb COW */
+ 
+	hdr->hop_limit--;
+
+	IP6_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS);
+	return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish);
+
+error:
+	IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS);
+drop:
+	kfree_skb(skb);
+	return -EINVAL;
+}
+
+static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
+{
+	to->pkt_type = from->pkt_type;
+	to->priority = from->priority;
+	to->protocol = from->protocol;
+	to->security = from->security;
+	dst_release(to->dst);
+	to->dst = dst_clone(from->dst);
+	to->dev = from->dev;
+
+#ifdef CONFIG_NET_SCHED
+	to->tc_index = from->tc_index;
+#endif
+#ifdef CONFIG_NETFILTER
+	to->nfmark = from->nfmark;
+	/* Connection association is same as pre-frag packet */
+	to->nfct = from->nfct;
+	nf_conntrack_get(to->nfct);
+	to->nfctinfo = from->nfctinfo;
+#ifdef CONFIG_BRIDGE_NETFILTER
+	nf_bridge_put(to->nf_bridge);
+	to->nf_bridge = from->nf_bridge;
+	nf_bridge_get(to->nf_bridge);
+#endif
+#ifdef CONFIG_NETFILTER_DEBUG
+	to->nf_debug = from->nf_debug;
+#endif
+#endif
+}
+
+int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
+{
+	u16 offset = sizeof(struct ipv6hdr);
+	struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
+	unsigned int packet_len = skb->tail - skb->nh.raw;
+	int found_rhdr = 0;
+	*nexthdr = &skb->nh.ipv6h->nexthdr;
+
+	while (offset + 1 <= packet_len) {
+
+		switch (**nexthdr) {
+
+		case NEXTHDR_HOP:
+		case NEXTHDR_ROUTING:
+		case NEXTHDR_DEST:
+			if (**nexthdr == NEXTHDR_ROUTING) found_rhdr = 1;
+			if (**nexthdr == NEXTHDR_DEST && found_rhdr) return offset;
+			offset += ipv6_optlen(exthdr);
+			*nexthdr = &exthdr->nexthdr;
+			exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
+			break;
+		default :
+			return offset;
+		}
+	}
+
+	return offset;
+}
+
+static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
+{
+	struct net_device *dev;
+	struct sk_buff *frag;
+	struct rt6_info *rt = (struct rt6_info*)skb->dst;
+	struct ipv6hdr *tmp_hdr;
+	struct frag_hdr *fh;
+	unsigned int mtu, hlen, left, len;
+	u32 frag_id = 0;
+	int ptr, offset = 0, err=0;
+	u8 *prevhdr, nexthdr = 0;
+
+	dev = rt->u.dst.dev;
+	hlen = ip6_find_1stfragopt(skb, &prevhdr);
+	nexthdr = *prevhdr;
+
+	mtu = dst_mtu(&rt->u.dst) - hlen - sizeof(struct frag_hdr);
+
+	if (skb_shinfo(skb)->frag_list) {
+		int first_len = skb_pagelen(skb);
+
+		if (first_len - hlen > mtu ||
+		    ((first_len - hlen) & 7) ||
+		    skb_cloned(skb))
+			goto slow_path;
+
+		for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
+			/* Correct geometry. */
+			if (frag->len > mtu ||
+			    ((frag->len & 7) && frag->next) ||
+			    skb_headroom(frag) < hlen)
+			    goto slow_path;
+
+			/* Correct socket ownership. */
+			if (frag->sk == NULL)
+				goto slow_path;
+
+			/* Partially cloned skb? */
+			if (skb_shared(frag))
+				goto slow_path;
+		}
+
+		err = 0;
+		offset = 0;
+		frag = skb_shinfo(skb)->frag_list;
+		skb_shinfo(skb)->frag_list = NULL;
+		/* BUILD HEADER */
+
+		tmp_hdr = kmalloc(hlen, GFP_ATOMIC);
+		if (!tmp_hdr) {
+			IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
+			return -ENOMEM;
+		}
+
+		*prevhdr = NEXTHDR_FRAGMENT;
+		memcpy(tmp_hdr, skb->nh.raw, hlen);
+		__skb_pull(skb, hlen);
+		fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
+		skb->nh.raw = __skb_push(skb, hlen);
+		memcpy(skb->nh.raw, tmp_hdr, hlen);
+
+		ipv6_select_ident(skb, fh);
+		fh->nexthdr = nexthdr;
+		fh->reserved = 0;
+		fh->frag_off = htons(IP6_MF);
+		frag_id = fh->identification;
+
+		first_len = skb_pagelen(skb);
+		skb->data_len = first_len - skb_headlen(skb);
+		skb->len = first_len;
+		skb->nh.ipv6h->payload_len = htons(first_len - sizeof(struct ipv6hdr));
+ 
+
+		for (;;) {
+			/* Prepare header of the next frame,
+			 * before previous one went down. */
+			if (frag) {
+				frag->ip_summed = CHECKSUM_NONE;
+				frag->h.raw = frag->data;
+				fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
+				frag->nh.raw = __skb_push(frag, hlen);
+				memcpy(frag->nh.raw, tmp_hdr, hlen);
+				offset += skb->len - hlen - sizeof(struct frag_hdr);
+				fh->nexthdr = nexthdr;
+				fh->reserved = 0;
+				fh->frag_off = htons(offset);
+				if (frag->next != NULL)
+					fh->frag_off |= htons(IP6_MF);
+				fh->identification = frag_id;
+				frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr));
+				ip6_copy_metadata(frag, skb);
+			}
+			
+			err = output(skb);
+			if (err || !frag)
+				break;
+
+			skb = frag;
+			frag = skb->next;
+			skb->next = NULL;
+		}
+
+		if (tmp_hdr)
+			kfree(tmp_hdr);
+
+		if (err == 0) {
+			IP6_INC_STATS(IPSTATS_MIB_FRAGOKS);
+			return 0;
+		}
+
+		while (frag) {
+			skb = frag->next;
+			kfree_skb(frag);
+			frag = skb;
+		}
+
+		IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
+		return err;
+	}
+
+slow_path:
+	left = skb->len - hlen;		/* Space per frame */
+	ptr = hlen;			/* Where to start from */
+
+	/*
+	 *	Fragment the datagram.
+	 */
+
+	*prevhdr = NEXTHDR_FRAGMENT;
+
+	/*
+	 *	Keep copying data until we run out.
+	 */
+	while(left > 0)	{
+		len = left;
+		/* IF: it doesn't fit, use 'mtu' - the data space left */
+		if (len > mtu)
+			len = mtu;
+		/* IF: we are not sending upto and including the packet end
+		   then align the next start on an eight byte boundary */
+		if (len < left)	{
+			len &= ~7;
+		}
+		/*
+		 *	Allocate buffer.
+		 */
+
+		if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) {
+			NETDEBUG(printk(KERN_INFO "IPv6: frag: no memory for new fragment!\n"));
+			IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
+			err = -ENOMEM;
+			goto fail;
+		}
+
+		/*
+		 *	Set up data on packet
+		 */
+
+		ip6_copy_metadata(frag, skb);
+		skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev));
+		skb_put(frag, len + hlen + sizeof(struct frag_hdr));
+		frag->nh.raw = frag->data;
+		fh = (struct frag_hdr*)(frag->data + hlen);
+		frag->h.raw = frag->data + hlen + sizeof(struct frag_hdr);
+
+		/*
+		 *	Charge the memory for the fragment to any owner
+		 *	it might possess
+		 */
+		if (skb->sk)
+			skb_set_owner_w(frag, skb->sk);
+
+		/*
+		 *	Copy the packet header into the new buffer.
+		 */
+		memcpy(frag->nh.raw, skb->data, hlen);
+
+		/*
+		 *	Build fragment header.
+		 */
+		fh->nexthdr = nexthdr;
+		fh->reserved = 0;
+		if (frag_id) {
+			ipv6_select_ident(skb, fh);
+			frag_id = fh->identification;
+		} else
+			fh->identification = frag_id;
+
+		/*
+		 *	Copy a block of the IP datagram.
+		 */
+		if (skb_copy_bits(skb, ptr, frag->h.raw, len))
+			BUG();
+		left -= len;
+
+		fh->frag_off = htons(offset);
+		if (left > 0)
+			fh->frag_off |= htons(IP6_MF);
+		frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr));
+
+		ptr += len;
+		offset += len;
+
+		/*
+		 *	Put this fragment into the sending queue.
+		 */
+
+		IP6_INC_STATS(IPSTATS_MIB_FRAGCREATES);
+
+		err = output(frag);
+		if (err)
+			goto fail;
+	}
+	kfree_skb(skb);
+	IP6_INC_STATS(IPSTATS_MIB_FRAGOKS);
+	return err;
+
+fail:
+	kfree_skb(skb); 
+	IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
+	return err;
+}
+
+int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
+{
+	int err = 0;
+
+	*dst = NULL;
+	if (sk) {
+		struct ipv6_pinfo *np = inet6_sk(sk);
+	
+		*dst = sk_dst_check(sk, np->dst_cookie);
+		if (*dst) {
+			struct rt6_info *rt = (struct rt6_info*)*dst;
+	
+				/* Yes, checking route validity in not connected
+				   case is not very simple. Take into account,
+				   that we do not support routing by source, TOS,
+				   and MSG_DONTROUTE 		--ANK (980726)
+	
+				   1. If route was host route, check that
+				      cached destination is current.
+				      If it is network route, we still may
+				      check its validity using saved pointer
+				      to the last used address: daddr_cache.
+				      We do not want to save whole address now,
+				      (because main consumer of this service
+				       is tcp, which has not this problem),
+				      so that the last trick works only on connected
+				      sockets.
+				   2. oif also should be the same.
+				 */
+	
+			if (((rt->rt6i_dst.plen != 128 ||
+			      !ipv6_addr_equal(&fl->fl6_dst, &rt->rt6i_dst.addr))
+			     && (np->daddr_cache == NULL ||
+				 !ipv6_addr_equal(&fl->fl6_dst, np->daddr_cache)))
+			    || (fl->oif && fl->oif != (*dst)->dev->ifindex)) {
+				dst_release(*dst);
+				*dst = NULL;
+			}
+		}
+	}
+
+	if (*dst == NULL)
+		*dst = ip6_route_output(sk, fl);
+
+	if ((err = (*dst)->error))
+		goto out_err_release;
+
+	if (ipv6_addr_any(&fl->fl6_src)) {
+		err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src);
+
+		if (err) {
+#if IP6_DEBUG >= 2
+			printk(KERN_DEBUG "ip6_dst_lookup: "
+			       "no available source address\n");
+#endif
+			goto out_err_release;
+		}
+	}
+
+	return 0;
+
+out_err_release:
+	dst_release(*dst);
+	*dst = NULL;
+	return err;
+}
+
+int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb),
+		    void *from, int length, int transhdrlen,
+		    int hlimit, struct ipv6_txoptions *opt, struct flowi *fl, struct rt6_info *rt,
+		    unsigned int flags)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct sk_buff *skb;
+	unsigned int maxfraglen, fragheaderlen;
+	int exthdrlen;
+	int hh_len;
+	int mtu;
+	int copy;
+	int err;
+	int offset = 0;
+	int csummode = CHECKSUM_NONE;
+
+	if (flags&MSG_PROBE)
+		return 0;
+	if (skb_queue_empty(&sk->sk_write_queue)) {
+		/*
+		 * setup for corking
+		 */
+		if (opt) {
+			if (np->cork.opt == NULL) {
+				np->cork.opt = kmalloc(opt->tot_len,
+						       sk->sk_allocation);
+				if (unlikely(np->cork.opt == NULL))
+					return -ENOBUFS;
+			} else if (np->cork.opt->tot_len < opt->tot_len) {
+				printk(KERN_DEBUG "ip6_append_data: invalid option length\n");
+				return -EINVAL;
+			}
+			memcpy(np->cork.opt, opt, opt->tot_len);
+			inet->cork.flags |= IPCORK_OPT;
+			/* need source address above miyazawa*/
+		}
+		dst_hold(&rt->u.dst);
+		np->cork.rt = rt;
+		inet->cork.fl = *fl;
+		np->cork.hop_limit = hlimit;
+		inet->cork.fragsize = mtu = dst_mtu(rt->u.dst.path);
+		if (dst_allfrag(rt->u.dst.path))
+			inet->cork.flags |= IPCORK_ALLFRAG;
+		inet->cork.length = 0;
+		sk->sk_sndmsg_page = NULL;
+		sk->sk_sndmsg_off = 0;
+		exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0);
+		length += exthdrlen;
+		transhdrlen += exthdrlen;
+	} else {
+		rt = np->cork.rt;
+		fl = &inet->cork.fl;
+		if (inet->cork.flags & IPCORK_OPT)
+			opt = np->cork.opt;
+		transhdrlen = 0;
+		exthdrlen = 0;
+		mtu = inet->cork.fragsize;
+	}
+
+	hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
+
+	fragheaderlen = sizeof(struct ipv6hdr) + (opt ? opt->opt_nflen : 0);
+	maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
+
+	if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
+		if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
+			ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen);
+			return -EMSGSIZE;
+		}
+	}
+
+	/*
+	 * Let's try using as much space as possible.
+	 * Use MTU if total length of the message fits into the MTU.
+	 * Otherwise, we need to reserve fragment header and
+	 * fragment alignment (= 8-15 octects, in total).
+	 *
+	 * Note that we may need to "move" the data from the tail of
+	 * of the buffer to the new fragment when we split 
+	 * the message.
+	 *
+	 * FIXME: It may be fragmented into multiple chunks 
+	 *        at once if non-fragmentable extension headers
+	 *        are too large.
+	 * --yoshfuji 
+	 */
+
+	inet->cork.length += length;
+
+	if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
+		goto alloc_new_skb;
+
+	while (length > 0) {
+		/* Check if the remaining data fits into current packet. */
+		copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
+		if (copy < length)
+			copy = maxfraglen - skb->len;
+
+		if (copy <= 0) {
+			char *data;
+			unsigned int datalen;
+			unsigned int fraglen;
+			unsigned int fraggap;
+			unsigned int alloclen;
+			struct sk_buff *skb_prev;
+alloc_new_skb:
+			skb_prev = skb;
+
+			/* There's no room in the current skb */
+			if (skb_prev)
+				fraggap = skb_prev->len - maxfraglen;
+			else
+				fraggap = 0;
+
+			/*
+			 * If remaining data exceeds the mtu,
+			 * we know we need more fragment(s).
+			 */
+			datalen = length + fraggap;
+			if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
+				datalen = maxfraglen - fragheaderlen;
+
+			fraglen = datalen + fragheaderlen;
+			if ((flags & MSG_MORE) &&
+			    !(rt->u.dst.dev->features&NETIF_F_SG))
+				alloclen = mtu;
+			else
+				alloclen = datalen + fragheaderlen;
+
+			/*
+			 * The last fragment gets additional space at tail.
+			 * Note: we overallocate on fragments with MSG_MODE
+			 * because we have no idea if we're the last one.
+			 */
+			if (datalen == length + fraggap)
+				alloclen += rt->u.dst.trailer_len;
+
+			/*
+			 * We just reserve space for fragment header.
+			 * Note: this may be overallocation if the message 
+			 * (without MSG_MORE) fits into the MTU.
+			 */
+			alloclen += sizeof(struct frag_hdr);
+
+			if (transhdrlen) {
+				skb = sock_alloc_send_skb(sk,
+						alloclen + hh_len,
+						(flags & MSG_DONTWAIT), &err);
+			} else {
+				skb = NULL;
+				if (atomic_read(&sk->sk_wmem_alloc) <=
+				    2 * sk->sk_sndbuf)
+					skb = sock_wmalloc(sk,
+							   alloclen + hh_len, 1,
+							   sk->sk_allocation);
+				if (unlikely(skb == NULL))
+					err = -ENOBUFS;
+			}
+			if (skb == NULL)
+				goto error;
+			/*
+			 *	Fill in the control structures
+			 */
+			skb->ip_summed = csummode;
+			skb->csum = 0;
+			/* reserve for fragmentation */
+			skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
+
+			/*
+			 *	Find where to start putting bytes
+			 */
+			data = skb_put(skb, fraglen);
+			skb->nh.raw = data + exthdrlen;
+			data += fragheaderlen;
+			skb->h.raw = data + exthdrlen;
+
+			if (fraggap) {
+				skb->csum = skb_copy_and_csum_bits(
+					skb_prev, maxfraglen,
+					data + transhdrlen, fraggap, 0);
+				skb_prev->csum = csum_sub(skb_prev->csum,
+							  skb->csum);
+				data += fraggap;
+				skb_trim(skb_prev, maxfraglen);
+			}
+			copy = datalen - transhdrlen - fraggap;
+			if (copy < 0) {
+				err = -EINVAL;
+				kfree_skb(skb);
+				goto error;
+			} else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
+				err = -EFAULT;
+				kfree_skb(skb);
+				goto error;
+			}
+
+			offset += copy;
+			length -= datalen - fraggap;
+			transhdrlen = 0;
+			exthdrlen = 0;
+			csummode = CHECKSUM_NONE;
+
+			/*
+			 * Put the packet on the pending queue
+			 */
+			__skb_queue_tail(&sk->sk_write_queue, skb);
+			continue;
+		}
+
+		if (copy > length)
+			copy = length;
+
+		if (!(rt->u.dst.dev->features&NETIF_F_SG)) {
+			unsigned int off;
+
+			off = skb->len;
+			if (getfrag(from, skb_put(skb, copy),
+						offset, copy, off, skb) < 0) {
+				__skb_trim(skb, off);
+				err = -EFAULT;
+				goto error;
+			}
+		} else {
+			int i = skb_shinfo(skb)->nr_frags;
+			skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1];
+			struct page *page = sk->sk_sndmsg_page;
+			int off = sk->sk_sndmsg_off;
+			unsigned int left;
+
+			if (page && (left = PAGE_SIZE - off) > 0) {
+				if (copy >= left)
+					copy = left;
+				if (page != frag->page) {
+					if (i == MAX_SKB_FRAGS) {
+						err = -EMSGSIZE;
+						goto error;
+					}
+					get_page(page);
+					skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
+					frag = &skb_shinfo(skb)->frags[i];
+				}
+			} else if(i < MAX_SKB_FRAGS) {
+				if (copy > PAGE_SIZE)
+					copy = PAGE_SIZE;
+				page = alloc_pages(sk->sk_allocation, 0);
+				if (page == NULL) {
+					err = -ENOMEM;
+					goto error;
+				}
+				sk->sk_sndmsg_page = page;
+				sk->sk_sndmsg_off = 0;
+
+				skb_fill_page_desc(skb, i, page, 0, 0);
+				frag = &skb_shinfo(skb)->frags[i];
+				skb->truesize += PAGE_SIZE;
+				atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc);
+			} else {
+				err = -EMSGSIZE;
+				goto error;
+			}
+			if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) {
+				err = -EFAULT;
+				goto error;
+			}
+			sk->sk_sndmsg_off += copy;
+			frag->size += copy;
+			skb->len += copy;
+			skb->data_len += copy;
+		}
+		offset += copy;
+		length -= copy;
+	}
+	return 0;
+error:
+	inet->cork.length -= length;
+	IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
+	return err;
+}
+
+int ip6_push_pending_frames(struct sock *sk)
+{
+	struct sk_buff *skb, *tmp_skb;
+	struct sk_buff **tail_skb;
+	struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct ipv6hdr *hdr;
+	struct ipv6_txoptions *opt = np->cork.opt;
+	struct rt6_info *rt = np->cork.rt;
+	struct flowi *fl = &inet->cork.fl;
+	unsigned char proto = fl->proto;
+	int err = 0;
+
+	if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL)
+		goto out;
+	tail_skb = &(skb_shinfo(skb)->frag_list);
+
+	/* move skb->data to ip header from ext header */
+	if (skb->data < skb->nh.raw)
+		__skb_pull(skb, skb->nh.raw - skb->data);
+	while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
+		__skb_pull(tmp_skb, skb->h.raw - skb->nh.raw);
+		*tail_skb = tmp_skb;
+		tail_skb = &(tmp_skb->next);
+		skb->len += tmp_skb->len;
+		skb->data_len += tmp_skb->len;
+#if 0 /* Logically correct, but useless work, ip_fragment() will have to undo */
+		skb->truesize += tmp_skb->truesize;
+		__sock_put(tmp_skb->sk);
+		tmp_skb->destructor = NULL;
+		tmp_skb->sk = NULL;
+#endif
+	}
+
+	ipv6_addr_copy(final_dst, &fl->fl6_dst);
+	__skb_pull(skb, skb->h.raw - skb->nh.raw);
+	if (opt && opt->opt_flen)
+		ipv6_push_frag_opts(skb, opt, &proto);
+	if (opt && opt->opt_nflen)
+		ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
+
+	skb->nh.ipv6h = hdr = (struct ipv6hdr*) skb_push(skb, sizeof(struct ipv6hdr));
+	
+	*(u32*)hdr = fl->fl6_flowlabel | htonl(0x60000000);
+
+	if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN)
+		hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+	else
+		hdr->payload_len = 0;
+	hdr->hop_limit = np->cork.hop_limit;
+	hdr->nexthdr = proto;
+	ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
+	ipv6_addr_copy(&hdr->daddr, final_dst);
+
+	skb->dst = dst_clone(&rt->u.dst);
+	IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);	
+	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output);
+	if (err) {
+		if (err > 0)
+			err = inet->recverr ? net_xmit_errno(err) : 0;
+		if (err)
+			goto error;
+	}
+
+out:
+	inet->cork.flags &= ~IPCORK_OPT;
+	if (np->cork.opt) {
+		kfree(np->cork.opt);
+		np->cork.opt = NULL;
+	}
+	if (np->cork.rt) {
+		dst_release(&np->cork.rt->u.dst);
+		np->cork.rt = NULL;
+		inet->cork.flags &= ~IPCORK_ALLFRAG;
+	}
+	memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
+	return err;
+error:
+	goto out;
+}
+
+void ip6_flush_pending_frames(struct sock *sk)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct sk_buff *skb;
+
+	while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
+		IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
+		kfree_skb(skb);
+	}
+
+	inet->cork.flags &= ~IPCORK_OPT;
+
+	if (np->cork.opt) {
+		kfree(np->cork.opt);
+		np->cork.opt = NULL;
+	}
+	if (np->cork.rt) {
+		dst_release(&np->cork.rt->u.dst);
+		np->cork.rt = NULL;
+		inet->cork.flags &= ~IPCORK_ALLFRAG;
+	}
+	memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
+}