@@ -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))
@@ -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)
@@ -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",
@@ -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)) {
Router Alert option is very small and we can store the value itself in the skb. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> --- include/linux/ipv6.h | 3 ++- include/uapi/linux/ipv6.h | 2 ++ net/ipv6/exthdrs.c | 3 ++- net/ipv6/ip6_input.c | 5 ++--- 4 files changed, 8 insertions(+), 5 deletions(-)