From e110861f86094cd78cc85593b873970092deb43a Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Tue, 13 May 2014 10:17:33 -0700 Subject: net: add a sysctl to reflect the fwmark on replies Kernel-originated IP packets that have no user socket associated with them (e.g., ICMP errors and echo replies, TCP RSTs, etc.) are emitted with a mark of zero. Add a sysctl to make them have the same mark as the packet they are replying to. This allows an administrator that wishes to do so to use mark-based routing, firewalling, etc. for these replies by marking the original packets inbound. Tested using user-mode linux: - ICMP/ICMPv6 echo replies and errors. - TCP RST packets (IPv4 and IPv6). Signed-off-by: Lorenzo Colitti Signed-off-by: David S. Miller --- net/ipv4/ip_output.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/ipv4/ip_output.c') diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 6aa4380fde1a..6e231ab58d65 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -1546,7 +1546,8 @@ void ip_send_unicast_reply(struct net *net, struct sk_buff *skb, __be32 daddr, daddr = replyopts.opt.opt.faddr; } - flowi4_init_output(&fl4, arg->bound_dev_if, 0, + flowi4_init_output(&fl4, arg->bound_dev_if, + IP4_REPLY_MARK(net, skb->mark), RT_TOS(arg->tos), RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol, ip_reply_arg_flowi_flags(arg), -- cgit v1.2.2