upload tizen1.0 sourceHEADmaster2.0alpha

1 files changed, 898 insertions, 0 deletions

diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
new file mode 100644
index 00000000..262f105d
--- /dev/null
+++ b/net/ipv6/exthdrs.c
@@ -0,0 +1,898 @@
+/*
+ *	Extension Header handling for IPv6
+ *	Linux INET6 implementation
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>
+ *	Andi Kleen		<ak@muc.de>
+ *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
+ *
+ *	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:
+ *	yoshfuji		: ensure not to overrun while parsing
+ *				  tlv options.
+ *	Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs().
+ *	YOSHIFUJI Hideaki @USAGI  Register inbound extension header
+ *				  handlers as inet6_protocol{}.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/in6.h>
+#include <linux/icmpv6.h>
+#include <linux/slab.h>
+
+#include <net/dst.h>
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/transp_v6.h>
+#include <net/rawv6.h>
+#include <net/ndisc.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+#include <net/xfrm.h>
+#endif
+
+#include <asm/uaccess.h>
+
+int ipv6_find_tlv(struct sk_buff *skb, int offset, int type)
+{
+	const unsigned char *nh = skb_network_header(skb);
+	int packet_len = skb->tail - skb->network_header;
+	struct ipv6_opt_hdr *hdr;
+	int len;
+
+	if (offset + 2 > packet_len)
+		goto bad;
+	hdr = (struct ipv6_opt_hdr *)(nh + offset);
+	len = ((hdr->hdrlen + 1) << 3);
+
+	if (offset + len > packet_len)
+		goto bad;
+
+	offset += 2;
+	len -= 2;
+
+	while (len > 0) {
+		int opttype = nh[offset];
+		int optlen;
+
+		if (opttype == type)
+			return offset;
+
+		switch (opttype) {
+		case IPV6_TLV_PAD0:
+			optlen = 1;
+			break;
+		default:
+			optlen = nh[offset + 1] + 2;
+			if (optlen > len)
+				goto bad;
+			break;
+		}
+		offset += optlen;
+		len -= optlen;
+	}
+	/* not_found */
+ bad:
+	return -1;
+}
+EXPORT_SYMBOL_GPL(ipv6_find_tlv);
+
+/*
+ *	Parsing tlv encoded headers.
+ *
+ *	Parsing function "func" returns 1, if parsing succeed
+ *	and 0, if it failed.
+ *	It MUST NOT touch skb->h.
+ */
+
+struct tlvtype_proc {
+	int	type;
+	int	(*func)(struct sk_buff *skb, int offset);
+};
+
+/*********************
+  Generic functions
+ *********************/
+
+/* An unknown option is detected, decide what to do */
+
+static int ip6_tlvopt_unknown(struct sk_buff *skb, int optoff)
+{
+	switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
+	case 0: /* ignore */
+		return 1;
+
+	case 1: /* drop packet */
+		break;
+
+	case 3: /* Send ICMP if not a multicast address and drop packet */
+		/* Actually, it is redundant check. icmp_send
+		   will recheck in any case.
+		 */
+		if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
+			break;
+	case 2: /* send ICMP PARM PROB regardless and drop packet */
+		icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
+		return 0;
+	}
+
+	kfree_skb(skb);
+	return 0;
+}
+
+/* Parse tlv encoded option header (hop-by-hop or destination) */
+
+static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff *skb)
+{
+	struct tlvtype_proc *curr;
+	const unsigned char *nh = skb_network_header(skb);
+	int off = skb_network_header_len(skb);
+	int len = (skb_transport_header(skb)[1] + 1) << 3;
+
+	if (skb_transport_offset(skb) + len > skb_headlen(skb))
+		goto bad;
+
+	off += 2;
+	len -= 2;
+
+	while (len > 0) {
+		int optlen = nh[off + 1] + 2;
+
+		switch (nh[off]) {
+		case IPV6_TLV_PAD0:
+			optlen = 1;
+			break;
+
+		case IPV6_TLV_PADN:
+			break;
+
+		default: /* Other TLV code so scan list */
+			if (optlen > len)
+				goto bad;
+			for (curr=procs; curr->type >= 0; curr++) {
+				if (curr->type == nh[off]) {
+					/* type specific length/alignment
+					   checks will be performed in the
+					   func(). */
+					if (curr->func(skb, off) == 0)
+						return 0;
+					break;
+				}
+			}
+			if (curr->type < 0) {
+				if (ip6_tlvopt_unknown(skb, off) == 0)
+					return 0;
+			}
+			break;
+		}
+		off += optlen;
+		len -= optlen;
+	}
+	if (len == 0)
+		return 1;
+bad:
+	kfree_skb(skb);
+	return 0;
+}
+
+/*****************************
+  Destination options header.
+ *****************************/
+
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+static int ipv6_dest_hao(struct sk_buff *skb, int optoff)
+{
+	struct ipv6_destopt_hao *hao;
+	struct inet6_skb_parm *opt = IP6CB(skb);
+	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+	struct in6_addr tmp_addr;
+	int ret;
+
+	if (opt->dsthao) {
+		LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n");
+		goto discard;
+	}
+	opt->dsthao = opt->dst1;
+	opt->dst1 = 0;
+
+	hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
+
+	if (hao->length != 16) {
+		LIMIT_NETDEBUG(
+			KERN_DEBUG "hao invalid option length = %d\n", hao->length);
+		goto discard;
+	}
+
+	if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) {
+		LIMIT_NETDEBUG(
+			KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr);
+		goto discard;
+	}
+
+	ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr,
+			       (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS);
+	if (unlikely(ret < 0))
+		goto discard;
+
+	if (skb_cloned(skb)) {
+		if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+			goto discard;
+
+		/* update all variable using below by copied skbuff */
+		hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) +
+						  optoff);
+		ipv6h = ipv6_hdr(skb);
+	}
+
+	if (skb->ip_summed == CHECKSUM_COMPLETE)
+		skb->ip_summed = CHECKSUM_NONE;
+
+	ipv6_addr_copy(&tmp_addr, &ipv6h->saddr);
+	ipv6_addr_copy(&ipv6h->saddr, &hao->addr);
+	ipv6_addr_copy(&hao->addr, &tmp_addr);
+
+	if (skb->tstamp.tv64 == 0)
+		__net_timestamp(skb);
+
+	return 1;
+
+ discard:
+	kfree_skb(skb);
+	return 0;
+}
+#endif
+
+static struct tlvtype_proc tlvprocdestopt_lst[] = {
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+	{
+		.type	= IPV6_TLV_HAO,
+		.func	= ipv6_dest_hao,
+	},
+#endif
+	{-1,			NULL}
+};
+
+static int ipv6_destopt_rcv(struct sk_buff *skb)
+{
+	struct inet6_skb_parm *opt = IP6CB(skb);
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+	__u16 dstbuf;
+#endif
+	struct dst_entry *dst;
+
+	if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
+	    !pskb_may_pull(skb, (skb_transport_offset(skb) +
+				 ((skb_transport_header(skb)[1] + 1) << 3)))) {
+		IP6_INC_STATS_BH(dev_net(skb_dst(skb)->dev), ip6_dst_idev(skb_dst(skb)),
+				 IPSTATS_MIB_INHDRERRORS);
+		kfree_skb(skb);
+		return -1;
+	}
+
+	opt->lastopt = opt->dst1 = skb_network_header_len(skb);
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+	dstbuf = opt->dst1;
+#endif
+
+	dst = dst_clone(skb_dst(skb));
+	if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) {
+		dst_release(dst);
+		skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
+		opt = IP6CB(skb);
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+		opt->nhoff = dstbuf;
+#else
+		opt->nhoff = opt->dst1;
+#endif
+		return 1;
+	}
+
+	IP6_INC_STATS_BH(dev_net(dst->dev),
+			 ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
+	dst_release(dst);
+	return -1;
+}
+
+/********************************
+  Routing header.
+ ********************************/
+
+/* called with rcu_read_lock() */
+static int ipv6_rthdr_rcv(struct sk_buff *skb)
+{
+	struct inet6_skb_parm *opt = IP6CB(skb);
+	struct in6_addr *addr = NULL;
+	struct in6_addr daddr;
+	struct inet6_dev *idev;
+	int n, i;
+	struct ipv6_rt_hdr *hdr;
+	struct rt0_hdr *rthdr;
+	struct net *net = dev_net(skb->dev);
+	int accept_source_route = net->ipv6.devconf_all->accept_source_route;
+
+	idev = __in6_dev_get(skb->dev);
+	if (idev && accept_source_route > idev->cnf.accept_source_route)
+		accept_source_route = idev->cnf.accept_source_route;
+
+	if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
+	    !pskb_may_pull(skb, (skb_transport_offset(skb) +
+				 ((skb_transport_header(skb)[1] + 1) << 3)))) {
+		IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+				 IPSTATS_MIB_INHDRERRORS);
+		kfree_skb(skb);
+		return -1;
+	}
+
+	hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
+
+	if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ||
+	    skb->pkt_type != PACKET_HOST) {
+		IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+				 IPSTATS_MIB_INADDRERRORS);
+		kfree_skb(skb);
+		return -1;
+	}
+
+looped_back:
+	if (hdr->segments_left == 0) {
+		switch (hdr->type) {
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+		case IPV6_SRCRT_TYPE_2:
+			/* Silently discard type 2 header unless it was
+			 * processed by own
+			 */
+			if (!addr) {
+				IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+						 IPSTATS_MIB_INADDRERRORS);
+				kfree_skb(skb);
+				return -1;
+			}
+			break;
+#endif
+		default:
+			break;
+		}
+
+		opt->lastopt = opt->srcrt = skb_network_header_len(skb);
+		skb->transport_header += (hdr->hdrlen + 1) << 3;
+		opt->dst0 = opt->dst1;
+		opt->dst1 = 0;
+		opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
+		return 1;
+	}
+
+	switch (hdr->type) {
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+	case IPV6_SRCRT_TYPE_2:
+		if (accept_source_route < 0)
+			goto unknown_rh;
+		/* Silently discard invalid RTH type 2 */
+		if (hdr->hdrlen != 2 || hdr->segments_left != 1) {
+			IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+					 IPSTATS_MIB_INHDRERRORS);
+			kfree_skb(skb);
+			return -1;
+		}
+		break;
+#endif
+	default:
+		goto unknown_rh;
+	}
+
+	/*
+	 *	This is the routing header forwarding algorithm from
+	 *	RFC 2460, page 16.
+	 */
+
+	n = hdr->hdrlen >> 1;
+
+	if (hdr->segments_left > n) {
+		IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+				 IPSTATS_MIB_INHDRERRORS);
+		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+				  ((&hdr->segments_left) -
+				   skb_network_header(skb)));
+		return -1;
+	}
+
+	/* We are about to mangle packet header. Be careful!
+	   Do not damage packets queued somewhere.
+	 */
+	if (skb_cloned(skb)) {
+		/* the copy is a forwarded packet */
+		if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
+			IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+					 IPSTATS_MIB_OUTDISCARDS);
+			kfree_skb(skb);
+			return -1;
+		}
+		hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
+	}
+
+	if (skb->ip_summed == CHECKSUM_COMPLETE)
+		skb->ip_summed = CHECKSUM_NONE;
+
+	i = n - --hdr->segments_left;
+
+	rthdr = (struct rt0_hdr *) hdr;
+	addr = rthdr->addr;
+	addr += i - 1;
+
+	switch (hdr->type) {
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+	case IPV6_SRCRT_TYPE_2:
+		if (xfrm6_input_addr(skb, (xfrm_address_t *)addr,
+				     (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
+				     IPPROTO_ROUTING) < 0) {
+			IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+					 IPSTATS_MIB_INADDRERRORS);
+			kfree_skb(skb);
+			return -1;
+		}
+		if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) {
+			IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+					 IPSTATS_MIB_INADDRERRORS);
+			kfree_skb(skb);
+			return -1;
+		}
+		break;
+#endif
+	default:
+		break;
+	}
+
+	if (ipv6_addr_is_multicast(addr)) {
+		IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+				 IPSTATS_MIB_INADDRERRORS);
+		kfree_skb(skb);
+		return -1;
+	}
+
+	ipv6_addr_copy(&daddr, addr);
+	ipv6_addr_copy(addr, &ipv6_hdr(skb)->daddr);
+	ipv6_addr_copy(&ipv6_hdr(skb)->daddr, &daddr);
+
+	skb_dst_drop(skb);
+	ip6_route_input(skb);
+	if (skb_dst(skb)->error) {
+		skb_push(skb, skb->data - skb_network_header(skb));
+		dst_input(skb);
+		return -1;
+	}
+
+	if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) {
+		if (ipv6_hdr(skb)->hop_limit <= 1) {
+			IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+					 IPSTATS_MIB_INHDRERRORS);
+			icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
+				    0);
+			kfree_skb(skb);
+			return -1;
+		}
+		ipv6_hdr(skb)->hop_limit--;
+		goto looped_back;
+	}
+
+	skb_push(skb, skb->data - skb_network_header(skb));
+	dst_input(skb);
+	return -1;
+
+unknown_rh:
+	IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS);
+	icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+			  (&hdr->type) - skb_network_header(skb));
+	return -1;
+}
+
+static const struct inet6_protocol rthdr_protocol = {
+	.handler	=	ipv6_rthdr_rcv,
+	.flags		=	INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR,
+};
+
+static const struct inet6_protocol destopt_protocol = {
+	.handler	=	ipv6_destopt_rcv,
+	.flags		=	INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR,
+};
+
+static const struct inet6_protocol nodata_protocol = {
+	.handler	=	dst_discard,
+	.flags		=	INET6_PROTO_NOPOLICY,
+};
+
+int __init ipv6_exthdrs_init(void)
+{
+	int ret;
+
+	ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING);
+	if (ret)
+		goto out;
+
+	ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
+	if (ret)
+		goto out_rthdr;
+
+	ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE);
+	if (ret)
+		goto out_destopt;
+
+out:
+	return ret;
+out_rthdr:
+	inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
+out_destopt:
+	inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
+	goto out;
+};
+
+void ipv6_exthdrs_exit(void)
+{
+	inet6_del_protocol(&nodata_protocol, IPPROTO_NONE);
+	inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
+	inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
+}
+
+/**********************************
+  Hop-by-hop options.
+ **********************************/
+
+/*
+ * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input().
+ */
+static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb)
+{
+	return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev);
+}
+
+static inline struct net *ipv6_skb_net(struct sk_buff *skb)
+{
+	return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev);
+}
+
+/* Router Alert as of RFC 2711 */
+
+static int ipv6_hop_ra(struct sk_buff *skb, int optoff)
+{
+	const unsigned char *nh = skb_network_header(skb);
+
+	if (nh[optoff + 1] == 2) {
+		IP6CB(skb)->ra = optoff;
+		return 1;
+	}
+	LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n",
+		       nh[optoff + 1]);
+	kfree_skb(skb);
+	return 0;
+}
+
+/* Jumbo payload */
+
+static int ipv6_hop_jumbo(struct sk_buff *skb, int optoff)
+{
+	const unsigned char *nh = skb_network_header(skb);
+	struct net *net = ipv6_skb_net(skb);
+	u32 pkt_len;
+
+	if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
+		LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
+			       nh[optoff+1]);
+		IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+				 IPSTATS_MIB_INHDRERRORS);
+		goto drop;
+	}
+
+	pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
+	if (pkt_len <= IPV6_MAXPLEN) {
+		IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+				 IPSTATS_MIB_INHDRERRORS);
+		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
+		return 0;
+	}
+	if (ipv6_hdr(skb)->payload_len) {
+		IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+				 IPSTATS_MIB_INHDRERRORS);
+		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
+		return 0;
+	}
+
+	if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
+		IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+				 IPSTATS_MIB_INTRUNCATEDPKTS);
+		goto drop;
+	}
+
+	if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
+		goto drop;
+
+	return 1;
+
+drop:
+	kfree_skb(skb);
+	return 0;
+}
+
+static struct tlvtype_proc tlvprochopopt_lst[] = {
+	{
+		.type	= IPV6_TLV_ROUTERALERT,
+		.func	= ipv6_hop_ra,
+	},
+	{
+		.type	= IPV6_TLV_JUMBO,
+		.func	= ipv6_hop_jumbo,
+	},
+	{ -1, }
+};
+
+int ipv6_parse_hopopts(struct sk_buff *skb)
+{
+	struct inet6_skb_parm *opt = IP6CB(skb);
+
+	/*
+	 * skb_network_header(skb) is equal to skb->data, and
+	 * skb_network_header_len(skb) is always equal to
+	 * sizeof(struct ipv6hdr) by definition of
+	 * hop-by-hop options.
+	 */
+	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) ||
+	    !pskb_may_pull(skb, (sizeof(struct ipv6hdr) +
+				 ((skb_transport_header(skb)[1] + 1) << 3)))) {
+		kfree_skb(skb);
+		return -1;
+	}
+
+	opt->hop = sizeof(struct ipv6hdr);
+	if (ip6_parse_tlv(tlvprochopopt_lst, skb)) {
+		skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
+		opt = IP6CB(skb);
+		opt->nhoff = sizeof(struct ipv6hdr);
+		return 1;
+	}
+	return -1;
+}
+
+/*
+ *	Creating outbound headers.
+ *
+ *	"build" functions work when skb is filled from head to tail (datagram)
+ *	"push"	functions work when headers are added from tail to head (tcp)
+ *
+ *	In both cases we assume, that caller reserved enough room
+ *	for headers.
+ */
+
+static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
+			    struct ipv6_rt_hdr *opt,
+			    struct in6_addr **addr_p)
+{
+	struct rt0_hdr *phdr, *ihdr;
+	int hops;
+
+	ihdr = (struct rt0_hdr *) opt;
+
+	phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3);
+	memcpy(phdr, ihdr, sizeof(struct rt0_hdr));
+
+	hops = ihdr->rt_hdr.hdrlen >> 1;
+
+	if (hops > 1)
+		memcpy(phdr->addr, ihdr->addr + 1,
+		       (hops - 1) * sizeof(struct in6_addr));
+
+	ipv6_addr_copy(phdr->addr + (hops - 1), *addr_p);
+	*addr_p = ihdr->addr;
+
+	phdr->rt_hdr.nexthdr = *proto;
+	*proto = NEXTHDR_ROUTING;
+}
+
+static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
+{
+	struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt));
+
+	memcpy(h, opt, ipv6_optlen(opt));
+	h->nexthdr = *proto;
+	*proto = type;
+}
+
+void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
+			  u8 *proto,
+			  struct in6_addr **daddr)
+{
+	if (opt->srcrt) {
+		ipv6_push_rthdr(skb, proto, opt->srcrt, daddr);
+		/*
+		 * IPV6_RTHDRDSTOPTS is ignored
+		 * unless IPV6_RTHDR is set (RFC3542).
+		 */
+		if (opt->dst0opt)
+			ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt);
+	}
+	if (opt->hopopt)
+		ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt);
+}
+
+EXPORT_SYMBOL(ipv6_push_nfrag_opts);
+
+void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto)
+{
+	if (opt->dst1opt)
+		ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt);
+}
+
+struct ipv6_txoptions *
+ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt)
+{
+	struct ipv6_txoptions *opt2;
+
+	opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC);
+	if (opt2) {
+		long dif = (char*)opt2 - (char*)opt;
+		memcpy(opt2, opt, opt->tot_len);
+		if (opt2->hopopt)
+			*((char**)&opt2->hopopt) += dif;
+		if (opt2->dst0opt)
+			*((char**)&opt2->dst0opt) += dif;
+		if (opt2->dst1opt)
+			*((char**)&opt2->dst1opt) += dif;
+		if (opt2->srcrt)
+			*((char**)&opt2->srcrt) += dif;
+	}
+	return opt2;
+}
+
+EXPORT_SYMBOL_GPL(ipv6_dup_options);
+
+static int ipv6_renew_option(void *ohdr,
+			     struct ipv6_opt_hdr __user *newopt, int newoptlen,
+			     int inherit,
+			     struct ipv6_opt_hdr **hdr,
+			     char **p)
+{
+	if (inherit) {
+		if (ohdr) {
+			memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr));
+			*hdr = (struct ipv6_opt_hdr *)*p;
+			*p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr));
+		}
+	} else {
+		if (newopt) {
+			if (copy_from_user(*p, newopt, newoptlen))
+				return -EFAULT;
+			*hdr = (struct ipv6_opt_hdr *)*p;
+			if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen)
+				return -EINVAL;
+			*p += CMSG_ALIGN(newoptlen);
+		}
+	}
+	return 0;
+}
+
+struct ipv6_txoptions *
+ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
+		   int newtype,
+		   struct ipv6_opt_hdr __user *newopt, int newoptlen)
+{
+	int tot_len = 0;
+	char *p;
+	struct ipv6_txoptions *opt2;
+	int err;
+
+	if (opt) {
+		if (newtype != IPV6_HOPOPTS && opt->hopopt)
+			tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt));
+		if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt)
+			tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt));
+		if (newtype != IPV6_RTHDR && opt->srcrt)
+			tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt));
+		if (newtype != IPV6_DSTOPTS && opt->dst1opt)
+			tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt));
+	}
+
+	if (newopt && newoptlen)
+		tot_len += CMSG_ALIGN(newoptlen);
+
+	if (!tot_len)
+		return NULL;
+
+	tot_len += sizeof(*opt2);
+	opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC);
+	if (!opt2)
+		return ERR_PTR(-ENOBUFS);
+
+	memset(opt2, 0, tot_len);
+
+	opt2->tot_len = tot_len;
+	p = (char *)(opt2 + 1);
+
+	err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen,
+				newtype != IPV6_HOPOPTS,
+				&opt2->hopopt, &p);
+	if (err)
+		goto out;
+
+	err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen,
+				newtype != IPV6_RTHDRDSTOPTS,
+				&opt2->dst0opt, &p);
+	if (err)
+		goto out;
+
+	err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen,
+				newtype != IPV6_RTHDR,
+				(struct ipv6_opt_hdr **)&opt2->srcrt, &p);
+	if (err)
+		goto out;
+
+	err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen,
+				newtype != IPV6_DSTOPTS,
+				&opt2->dst1opt, &p);
+	if (err)
+		goto out;
+
+	opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) +
+			  (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) +
+			  (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0);
+	opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0);
+
+	return opt2;
+out:
+	sock_kfree_s(sk, opt2, opt2->tot_len);
+	return ERR_PTR(err);
+}
+
+struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
+					  struct ipv6_txoptions *opt)
+{
+	/*
+	 * ignore the dest before srcrt unless srcrt is being included.
+	 * --yoshfuji
+	 */
+	if (opt && opt->dst0opt && !opt->srcrt) {
+		if (opt_space != opt) {
+			memcpy(opt_space, opt, sizeof(*opt_space));
+			opt = opt_space;
+		}
+		opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
+		opt->dst0opt = NULL;
+	}
+
+	return opt;
+}
+
+/**
+ * fl6_update_dst - update flowi destination address with info given
+ *                  by srcrt option, if any.
+ *
+ * @fl: flowi for which fl6_dst is to be updated
+ * @opt: struct ipv6_txoptions in which to look for srcrt opt
+ * @orig: copy of original fl6_dst address if modified
+ *
+ * Returns NULL if no txoptions or no srcrt, otherwise returns orig
+ * and initial value of fl->fl6_dst set in orig
+ */
+struct in6_addr *fl6_update_dst(struct flowi *fl,
+				const struct ipv6_txoptions *opt,
+				struct in6_addr *orig)
+{
+	if (!opt || !opt->srcrt)
+		return NULL;
+
+	ipv6_addr_copy(orig, &fl->fl6_dst);
+	ipv6_addr_copy(&fl->fl6_dst, ((struct rt0_hdr *)opt->srcrt)->addr);
+	return orig;
+}
+
+EXPORT_SYMBOL_GPL(fl6_update_dst);