ipv6: Change skb->data before using icmpv6_notify() to propagate redirect

In function ndisc_redirect_rcv(), the skb->data points to the transport
header, but function icmpv6_notify() need the skb->data points to the
inner IP packet. So before using icmpv6_notify() to propagate redirect,
change skb->data to point the inner IP packet that triggered the sending
of the Redirect, and introduce struct rd_msg to make it easy.

Signed-off-by: Duan Jiong <djduanjiong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Duan Jiong 2012-12-14 02:59:59 +00:00 committed by David S. Miller
parent 1e9f954516
commit 093d04d42f
2 changed files with 24 additions and 0 deletions

View File

@ -78,6 +78,13 @@ struct ra_msg {
__be32 retrans_timer;
};
struct rd_msg {
struct icmp6hdr icmph;
struct in6_addr target;
struct in6_addr dest;
__u8 opt[0];
};
struct nd_opt_hdr {
__u8 nd_opt_type;
__u8 nd_opt_len;

View File

@ -1314,6 +1314,12 @@ out:
static void ndisc_redirect_rcv(struct sk_buff *skb)
{
u8 *hdr;
struct ndisc_options ndopts;
struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
u32 ndoptlen = skb->tail - (skb->transport_header +
offsetof(struct rd_msg, opt));
#ifdef CONFIG_IPV6_NDISC_NODETYPE
switch (skb->ndisc_nodetype) {
case NDISC_NODETYPE_HOST:
@ -1330,6 +1336,17 @@ static void ndisc_redirect_rcv(struct sk_buff *skb)
return;
}
if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts))
return;
if (!ndopts.nd_opts_rh)
return;
hdr = (u8 *)ndopts.nd_opts_rh;
hdr += 8;
if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
return;
icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
}