From ded55a82a00dbfd3425cec63ed08114957241683 Mon Sep 17 00:00:00 2001 From: Yuxiang Zhu Date: Sun, 10 Sep 2023 16:22:02 +0000 Subject: T3655: Fix NAT problem with VRF Linux netfilter patch https://patchwork.ozlabs.org/project/netfilter-devel/patch/d0f84a97f9c86bec4d537536a26d0150873e640d.1439559328.git.daniel@iogearbox.net/ adds direction support for conntrack zones, which makes it possible to do NAT with conflicting IP address/port tuples from multiple, isolated tenants on a host. According to the description of the kernel patch: > ... overlapping tuples can be made unique with the zone identifier in original direction, where the NAT engine will then allocate a unique tuple in the commonly shared default zone for the reply direction. I did some basic tests in my lab and it worked fine to forward packets from eth0 to pppoe0. - eth0 192.168.1.1/24 in VRF red - pppoe0 dynamic public IP from ISP VRF default - set vrf name red protocols static route 0.0.0.0/0 interface pppoe0 vrf 'default' - set protocols static route 192.168.1.0/24 interface eth0 vrf 'red' `conntrack -L` shows something like: ``` tcp 6 113 ESTABLISHED src=192.168.1.2 dst=1.1.1.1 sport=58946 dport=80 zone-orig=250 packets=6 bytes=391 src=1.1.1.1 dst= sport=80 dport=58946 packets=4 bytes=602 [ASSURED] mark=0 helper=tns use=1 ``` It would be much appreciated if someone could test this with more complex VRF setup. --- data/templates/firewall/nftables-vrf-zones.j2 | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/data/templates/firewall/nftables-vrf-zones.j2 b/data/templates/firewall/nftables-vrf-zones.j2 index eecf47b78..3bce7312d 100644 --- a/data/templates/firewall/nftables-vrf-zones.j2 +++ b/data/templates/firewall/nftables-vrf-zones.j2 @@ -7,11 +7,11 @@ table inet vrf_zones { # Chain for inbound traffic chain vrf_zones_ct_in { type filter hook prerouting priority raw; policy accept; - counter ct zone set iifname map @ct_iface_map + counter ct original zone set iifname map @ct_iface_map } # Chain for locally-generated traffic chain vrf_zones_ct_out { type filter hook output priority raw; policy accept; - counter ct zone set oifname map @ct_iface_map + counter ct original zone set oifname map @ct_iface_map } } -- cgit v1.2.3