| Message ID | alpine.LFD.2.00.1108072158050.1423@ja.ssi.bg |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Julian Anastasov <ja@ssi.bg> Date: Sun, 7 Aug 2011 22:11:00 +0300 (EEST) > > TCP in some cases uses different global (raw) socket > to send RST and ACK. The transparent flag is not set there. > Currently, it is a problem for rerouting after the previous > change. > > Fix it by simplifying the checks in ip_route_me_harder > and use FLOWI_FLAG_ANYSRC even for sockets. It looks safe > because the initial routing allowed this source address to > be used and now we just have to make sure the packet is rerouted. > > As a side effect this also allows rerouting for normal > raw sockets that use spoofed source addresses which was not possible > even before we eliminated the ip_route_input call. > > Signed-off-by: Julian Anastasov <ja@ssi.bg> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff -urp v3.0/linux/net/ipv4/netfilter.c linux/net/ipv4/netfilter.c --- v3.0/linux/net/ipv4/netfilter.c 2011-07-22 09:43:32.862081622 +0300 +++ linux/net/ipv4/netfilter.c 2011-08-07 19:22:05.772347388 +0300 @@ -18,17 +18,15 @@ int ip_route_me_harder(struct sk_buff *s struct rtable *rt; struct flowi4 fl4 = {}; __be32 saddr = iph->saddr; - __u8 flags = 0; + __u8 flags = skb->sk ? inet_sk_flowi_flags(skb->sk) : 0; unsigned int hh_len; - if (!skb->sk && addr_type != RTN_LOCAL) { - if (addr_type == RTN_UNSPEC) - addr_type = inet_addr_type(net, saddr); - if (addr_type == RTN_LOCAL || addr_type == RTN_UNICAST) - flags |= FLOWI_FLAG_ANYSRC; - else - saddr = 0; - } + if (addr_type == RTN_UNSPEC) + addr_type = inet_addr_type(net, saddr); + if (addr_type == RTN_LOCAL || addr_type == RTN_UNICAST) + flags |= FLOWI_FLAG_ANYSRC; + else + saddr = 0; /* some non-standard hacks like ipt_REJECT.c:send_reset() can cause * packets with foreign saddr to appear on the NF_INET_LOCAL_OUT hook. @@ -38,7 +36,7 @@ int ip_route_me_harder(struct sk_buff *s fl4.flowi4_tos = RT_TOS(iph->tos); fl4.flowi4_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0; fl4.flowi4_mark = skb->mark; - fl4.flowi4_flags = skb->sk ? inet_sk_flowi_flags(skb->sk) : flags; + fl4.flowi4_flags = flags; rt = ip_route_output_key(net, &fl4); if (IS_ERR(rt)) return -1;
TCP in some cases uses different global (raw) socket to send RST and ACK. The transparent flag is not set there. Currently, it is a problem for rerouting after the previous change. Fix it by simplifying the checks in ip_route_me_harder and use FLOWI_FLAG_ANYSRC even for sockets. It looks safe because the initial routing allowed this source address to be used and now we just have to make sure the packet is rerouted. As a side effect this also allows rerouting for normal raw sockets that use spoofed source addresses which was not possible even before we eliminated the ip_route_input call. Signed-off-by: Julian Anastasov <ja@ssi.bg> --- -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html