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).
Change-Id: I95d896647b278d092ef331d1377b959da1deb042
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Git-commit: 3356997e1e1b2aa9959f046203e6d0b193bbd7f7
Git-repo: https://android.googlesource.com/kernel/common.git
[imaund@codeaurora.org: Resolve trivial merge conflicts.]
Signed-off-by: Ian Maund <imaund@codeaurora.org>
Signed-off-by: Samir Mehta <samirn@codeaurora.org>
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 3171f7f..f4ae36f 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -788,6 +788,13 @@
.mode = 0644,
.proc_handler = ipv4_tcp_mem,
},
+ {
+ .procname = "fwmark_reflect",
+ .data = &init_net.ipv4.sysctl_fwmark_reflect,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
{ }
};