| From 42d3b8e69761bf8866b11bef2664fa8eacd9398d Mon Sep 17 00:00:00 2001 |
| From: Duan Jiong <djduanjiong@gmail.com> |
| Date: Fri, 14 Dec 2012 02:59:59 +0000 |
| Subject: ipv6: Change skb->data before using icmpv6_notify() to propagate redirect |
| |
| |
| From: Duan Jiong <djduanjiong@gmail.com> |
| |
| [ Upstream commit 093d04d42fa094f6740bb188f0ad0c215ff61e2c ] |
| |
| 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> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| include/net/ndisc.h | 7 +++++++ |
| net/ipv6/ndisc.c | 17 +++++++++++++++++ |
| 2 files changed, 24 insertions(+) |
| |
| --- a/include/net/ndisc.h |
| +++ b/include/net/ndisc.h |
| @@ -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; |
| --- a/net/ipv6/ndisc.c |
| +++ b/net/ipv6/ndisc.c |
| @@ -1333,6 +1333,12 @@ 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: |
| @@ -1349,6 +1355,17 @@ static void ndisc_redirect_rcv(struct sk |
| 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); |
| } |
| |