From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Wei Subject: [PATCH] ipv4: Save nexthop address of LSRR/SSRR option to IPCB. Date: Wed, 23 Nov 2011 17:33:10 +0800 Message-ID: <4ECCBDD6.8080708@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 7bit Cc: netdev To: "David S. Miller" Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:56588 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750959Ab1KWJc7 (ORCPT ); Wed, 23 Nov 2011 04:32:59 -0500 Sender: netdev-owner@vger.kernel.org List-ID: We can not update iph->daddr in ip_options_rcv_srr(), It is too early. When some exception ocurred later (eg. in ip_forward() when goto sr_failed) we need the ip header be identical to the original one as ICMP need it. Add a field 'nexthop' in struct ip_options to save nexthop of LSRR or SSRR option. Signed-off-by: Li Wei --- include/net/inet_sock.h | 2 ++ net/ipv4/ip_forward.c | 2 +- net/ipv4/ip_options.c | 5 +++-- 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index b897d6e..f941964 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -31,6 +31,7 @@ /** struct ip_options - IP Options * * @faddr - Saved first hop address + * @nexthop - Saved nexthop address in LSRR and SSRR * @is_data - Options in __data, rather than skb * @is_strictroute - Strict source route * @srr_is_hit - Packet destination addr was our one @@ -41,6 +42,7 @@ */ struct ip_options { __be32 faddr; + __be32 nexthop; unsigned char optlen; unsigned char srr; unsigned char rr; diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c index 3b34d1c..29a07b6 100644 --- a/net/ipv4/ip_forward.c +++ b/net/ipv4/ip_forward.c @@ -84,7 +84,7 @@ int ip_forward(struct sk_buff *skb) rt = skb_rtable(skb); - if (opt->is_strictroute && ip_hdr(skb)->daddr != rt->rt_gateway) + if (opt->is_strictroute && opt->nexthop != rt->rt_gateway) goto sr_failed; if (unlikely(skb->len > dst_mtu(&rt->dst) && !skb_is_gso(skb) && diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c index 05d20cc..1e60f76 100644 --- a/net/ipv4/ip_options.c +++ b/net/ipv4/ip_options.c @@ -568,12 +568,13 @@ void ip_forward_options(struct sk_buff *skb) ) { if (srrptr + 3 > srrspace) break; - if (memcmp(&ip_hdr(skb)->daddr, &optptr[srrptr-1], 4) == 0) + if (memcmp(&opt->nexthop, &optptr[srrptr-1], 4) == 0) break; } if (srrptr + 3 <= srrspace) { opt->is_changed = 1; ip_rt_get_source(&optptr[srrptr-1], skb, rt); + ip_hdr(skb)->daddr = opt->nexthop; optptr[2] = srrptr+4; } else if (net_ratelimit()) printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n"); @@ -640,7 +641,7 @@ int ip_options_rcv_srr(struct sk_buff *skb) } if (srrptr <= srrspace) { opt->srr_is_hit = 1; - iph->daddr = nexthop; + opt->nexthop = nexthop; opt->is_changed = 1; } return 0; -- 1.7.3.2