From d8e2262a5044c1a05b4da51e5d0976f10c487a9f Mon Sep 17 00:00:00 2001 From: Saif Hasan Date: Fri, 21 Sep 2018 14:30:05 -0700 Subject: [PATCH] mpls: allow routes on ip6gre devices Summary: This appears to be necessary and sufficient change to enable `MPLS` on `ip6gre` tunnels (RFC4023). This diff allows IP6GRE devices to be recognized by MPLS kernel module and hence user can configure interface to accept packets with mpls headers as well setup mpls routes on them. Test Plan: Test plan consists of multiple containers connected via GRE-V6 tunnel. Then carrying out testing steps as below. - Carry out necessary sysctl settings on all containers ``` sysctl -w net.mpls.platform_labels=65536 sysctl -w net.mpls.ip_ttl_propagate=1 sysctl -w net.mpls.conf.lo.input=1 ``` - Establish IP6GRE tunnels ``` ip -6 tunnel add name if_1_2_1 mode ip6gre \ local 2401:db00:21:6048:feed:0::1 \ remote 2401:db00:21:6048:feed:0::2 key 1 ip link set dev if_1_2_1 up sysctl -w net.mpls.conf.if_1_2_1.input=1 ip -4 addr add 169.254.0.2/31 dev if_1_2_1 scope link ip -6 tunnel add name if_1_3_1 mode ip6gre \ local 2401:db00:21:6048:feed:0::1 \ remote 2401:db00:21:6048:feed:0::3 key 1 ip link set dev if_1_3_1 up sysctl -w net.mpls.conf.if_1_3_1.input=1 ip -4 addr add 169.254.0.4/31 dev if_1_3_1 scope link ``` - Install MPLS encap rules on node-1 towards node-2 ``` ip route add 192.168.0.11/32 nexthop encap mpls 32/64 \ via inet 169.254.0.3 dev if_1_2_1 ``` - Install MPLS forwarding rules on node-2 and node-3 ``` // node2 ip -f mpls route add 32 via inet 169.254.0.7 dev if_2_4_1 // node3 ip -f mpls route add 64 via inet 169.254.0.12 dev if_4_3_1 ``` - Ping 192.168.0.11 (node4) from 192.168.0.1 (node1) (where routing towards 192.168.0.1 is via IP route directly towards node1 from node4) ``` ping 192.168.0.11 ``` - tcpdump on interface to capture ping packets wrapped within MPLS header which inturn wrapped within IP6GRE header ``` 16:43:41.121073 IP6 2401:db00:21:6048:feed::1 > 2401:db00:21:6048:feed::2: DSTOPT GREv0, key=0x1, length 100: MPLS (label 32, exp 0, ttl 255) (label 64, exp 0, [S], ttl 255) IP 192.168.0.1 > 192.168.0.11: ICMP echo request, id 1208, seq 45, length 64 0x0000: 6000 2cdb 006c 3c3f 2401 db00 0021 6048 `.,..l Signed-off-by: David S. Miller --- net/mpls/af_mpls.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index 7a4de6d618b1..8fbe6cdbe255 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -1533,10 +1533,14 @@ static int mpls_dev_notify(struct notifier_block *this, unsigned long event, unsigned int flags; if (event == NETDEV_REGISTER) { - /* For now just support Ethernet, IPGRE, SIT and IPIP devices */ + + /* For now just support Ethernet, IPGRE, IP6GRE, SIT and + * IPIP devices + */ if (dev->type == ARPHRD_ETHER || dev->type == ARPHRD_LOOPBACK || dev->type == ARPHRD_IPGRE || + dev->type == ARPHRD_IP6GRE || dev->type == ARPHRD_SIT || dev->type == ARPHRD_TUNNEL) { mdev = mpls_add_dev(dev); -- GitLab