Commit dd3332bf authored by YOSHIFUJI Hideaki / 吉藤英明's avatar YOSHIFUJI Hideaki / 吉藤英明 Committed by David S. Miller
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ipv6: Store Router Alert option in IP6CB directly. 



Router Alert option is very small and we can store the value
itself in the skb.

Signed-off-by: default avatarYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 2b464f61

include/linux/ipv6.h

+2 −1
Original line number Diff line number Diff line
@@ -84,7 +84,7 @@ static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb) 


struct inet6_skb_parm {

	int			iif;

	__u16			ra;

	__be16			ra;

	__u16			hop;

	__u16			dst0;

	__u16			srcrt;
@@ -100,6 +100,7 @@ struct inet6_skb_parm { 
#define IP6SKB_XFRM_TRANSFORMED	1

#define IP6SKB_FORWARDED	2

#define IP6SKB_REROUTED		4

#define IP6SKB_ROUTERALERT	8

};



#define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))

include/uapi/linux/ipv6.h

+2 −0
Original line number Diff line number Diff line
@@ -63,6 +63,8 @@ struct ipv6_opt_hdr { 
#define ipv6_destopt_hdr ipv6_opt_hdr

#define ipv6_hopopt_hdr  ipv6_opt_hdr



/* Router Alert option values (RFC2711) */

#define IPV6_OPT_ROUTERALERT_MLD	0x0000	/* MLD(RFC2710) */



/*

 *	routing header type 0 (used in cmsghdr struct)

net/ipv6/exthdrs.c

+2 −1
Original line number Diff line number Diff line
@@ -553,7 +553,8 @@ static bool 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;

		IP6CB(skb)->flags |= IP6SKB_ROUTERALERT;

		memcpy(&IP6CB(skb)->ra, nh + optoff + 2, sizeof(IP6CB(skb)->ra));

		return true;

	}

	LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n",

net/ipv6/ip6_input.c

+2 −3
Original line number Diff line number Diff line
@@ -280,9 +280,8 @@ int ip6_mc_input(struct sk_buff *skb) 
		struct inet6_skb_parm *opt = IP6CB(skb);



		/* Check for MLD */

		if (unlikely(opt->ra)) {

		if (unlikely(opt->flags & IP6SKB_ROUTERALERT)) {

			/* Check if this is a mld message */

			u8 *ptr = skb_network_header(skb) + opt->ra;

			u8 nexthdr = hdr->nexthdr;

			__be16 frag_off;

			int offset;
@@ -290,7 +289,7 @@ int ip6_mc_input(struct sk_buff *skb) 
			/* Check if the value of Router Alert

			 * is for MLD (0x0000).

			 */

			if ((ptr[2] | ptr[3]) == 0) {

			if (opt->ra == htons(IPV6_OPT_ROUTERALERT_MLD)) {

				deliver = false;



				if (!ipv6_ext_hdr(nexthdr)) {