[ovs-dev] [PATCHv2] tunnel: add ip6gretap support.

Eli Britstein elibr at mellanox.com
Thu Jun 20 17:00:54 UTC 2019


On 6/20/2019 6:55 PM, William Tu wrote:
> The patch adds ip6gretap support. Tunnel type ip6gretap is a layer 2 GRE
> tunnel over IPv6, carrying inner ethernet packets and encap with GRE header
> with outer IPv6 header.  I tested it by running:
>    # make check-kernel
> under kernel 5.2 and for userspace:
>    # make check TESTSUITEFLAGS='-k ip6gretap'
>
> Signed-off-by: William Tu <u9012063 at gmail.com>
> ---
> v1-v2: rebase to master
>
> ---
>   Documentation/faq/configuration.rst | 12 +++++++
>   NEWS                                |  1 +
>   datapath/linux/compat/ip6_gre.c     |  2 +-
>   lib/dpif-netlink-rtnl.c             |  2 +-
>   lib/dpif-netlink.c                  |  4 ++-
>   lib/netdev-vport.c                  |  4 +--
>   lib/tnl-ports.c                     |  3 +-
>   tests/system-traffic.at             | 40 ++++++++++++++++++++++
>   tests/tunnel-push-pop-ipv6.at       | 68 +++++++++++++++++++++++++++++++++++++
>   9 files changed, 130 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/faq/configuration.rst b/Documentation/faq/configuration.rst
> index cb2c6b4eca98..c9bcfa8a790d 100644
> --- a/Documentation/faq/configuration.rst
> +++ b/Documentation/faq/configuration.rst
> @@ -212,6 +212,18 @@ Q: Does Open vSwitch support ERSPAN?
>                   options:erspan_ver=2 options:erspan_dir=1 \
>                   options:erspan_hwid=4
>   
> +Q: Does Open vSwitch support IPv6 GRE?
> +
> +    A: Yes. L2 tunnel interface GRE over IPv6 is supported.
> +    L3 GRE tunnel over IPv6 is not supported.
> +
> +    ::
> +
> +        $ ovs-vsctl add-br br0
> +        $ ovs-vsctl add-port br0 at_gretap0 -- \
> +                set int at_gretap0 type=ip6gretap \
> +                options:remote_ip=fc00:100::1
> +
>   Q: How do I connect two bridges?
>   
>       A: First, why do you want to do this?  Two connected bridges are not much
> diff --git a/NEWS b/NEWS
> index a38ab258fc6c..c7e84ed7931d 100644
> --- a/NEWS
> +++ b/NEWS
> @@ -47,6 +47,7 @@ Post-v2.11.0
>      - Linux datapath:
>        * Support for the kernel versions 4.19.x and 4.20.x.
>        * Support for the kernel version 5.0.x.
> +   - Add L2 GRE tunnel over IPv6 support.
>   
>   
>   v2.11.0 - 19 Feb 2019
> diff --git a/datapath/linux/compat/ip6_gre.c b/datapath/linux/compat/ip6_gre.c
> index ca4e66133570..ab50c72d0753 100644
> --- a/datapath/linux/compat/ip6_gre.c
> +++ b/datapath/linux/compat/ip6_gre.c
> @@ -2550,7 +2550,7 @@ static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
>   };
>   
>   static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
> -	.kind		= "ip6gre",
> +	.kind		= "ip6gretap",
>   	.maxtype	= RPL_IFLA_GRE_MAX,
>   	.policy		= ip6gre_policy,
>   	.priv_size	= sizeof(struct ip6_tnl),
> diff --git a/lib/dpif-netlink-rtnl.c b/lib/dpif-netlink-rtnl.c
> index 2e23a8c14fcf..d666f239aeed 100644
> --- a/lib/dpif-netlink-rtnl.c
> +++ b/lib/dpif-netlink-rtnl.c
> @@ -104,7 +104,7 @@ vport_type_to_kind(enum ovs_vport_type type,
>       case OVS_VPORT_TYPE_IP6ERSPAN:
>           return "ip6erspan";
>       case OVS_VPORT_TYPE_IP6GRE:
> -        return "ip6gre";
> +        return "ip6gretap";
>       case OVS_VPORT_TYPE_NETDEV:
>       case OVS_VPORT_TYPE_INTERNAL:
>       case OVS_VPORT_TYPE_LISP:
> diff --git a/lib/dpif-netlink.c b/lib/dpif-netlink.c
> index ba80a0079181..fc1d1591975e 100644
> --- a/lib/dpif-netlink.c
> +++ b/lib/dpif-netlink.c
> @@ -699,7 +699,7 @@ get_vport_type(const struct dpif_netlink_vport *vport)
>           return "ip6erspan";
>   
>       case OVS_VPORT_TYPE_IP6GRE:
> -        return "ip6gre";
> +        return "ip6gretap";
>   
>       case OVS_VPORT_TYPE_UNSPEC:
>       case __OVS_VPORT_TYPE_MAX:
> @@ -730,6 +730,8 @@ netdev_to_ovs_vport_type(const char *type)
>           return OVS_VPORT_TYPE_ERSPAN;
>       } else if (!strcmp(type, "ip6erspan")) {
>           return OVS_VPORT_TYPE_IP6ERSPAN;
> +    } else if (!strcmp(type, "ip6gretap")) {
> +        return OVS_VPORT_TYPE_IP6GRE;
>       } else if (!strcmp(type, "ip6gre")) {
>           return OVS_VPORT_TYPE_IP6GRE;
>       } else if (!strcmp(type, "gre")) {
> diff --git a/lib/netdev-vport.c b/lib/netdev-vport.c
> index 92a256af16ed..5a20415529eb 100644
> --- a/lib/netdev-vport.c
> +++ b/lib/netdev-vport.c
> @@ -1212,10 +1212,10 @@ netdev_vport_tunnel_register(void)
>             },
>             {{NULL, NULL, 0, 0}}
>           },
> -        { "ip6gre_sys",
> +        { "ip6gretap_sys",
>             {
>                 TUNNEL_FUNCTIONS_COMMON,
> -              .type = "ip6gre",
> +              .type = "ip6gretap",
>                 .build_header = netdev_gre_build_header,
>                 .push_header = netdev_gre_push_header,
>                 .pop_header = netdev_gre_pop_header
> diff --git a/lib/tnl-ports.c b/lib/tnl-ports.c
> index 17353046cc6e..62065c0027cd 100644
> --- a/lib/tnl-ports.c
> +++ b/lib/tnl-ports.c
> @@ -172,7 +172,8 @@ tnl_type_to_nw_proto(const char type[])
>           return IPPROTO_TCP;
>       }
>       if (!strcmp(type, "gre") || !strcmp(type, "erspan") ||
> -        !strcmp(type, "ip6erspan") || !strcmp(type, "ip6gre")) {
> +        !strcmp(type, "ip6erspan") || !strcmp(type, "ip6gre") ||
> +        !strcmp(type, "ip6gretap")) {
>           return IPPROTO_GRE;
>       }
>       if (!strcmp(type, "vxlan")) {
> diff --git a/tests/system-traffic.at b/tests/system-traffic.at
> index d23ee897b0b2..43056733794a 100644
> --- a/tests/system-traffic.at
> +++ b/tests/system-traffic.at
> @@ -340,6 +340,46 @@ NS_CHECK_EXEC([at_ns0], [ping -s 3200 -q -c 3 -i 0.3 -w 2 10.1.1.100 | FORMAT_PI
>   OVS_TRAFFIC_VSWITCHD_STOP
>   AT_CLEANUP
>   
> +AT_SETUP([datapath - ping over ip6gretap tunnel])
> +OVS_CHECK_KERNEL_EXCL(3, 10, 4, 15)
> +OVS_CHECK_GRE()
> +OVS_CHECK_ERSPAN()
> +
> +OVS_TRAFFIC_VSWITCHD_START()
> +ADD_BR([br-underlay])
> +
> +AT_CHECK([ovs-ofctl add-flow br0 "actions=normal"])
> +AT_CHECK([ovs-ofctl add-flow br-underlay "actions=normal"])
> +
> +ADD_NAMESPACES(at_ns0)
> +
> +dnl Set up underlay link from host into the namespace using veth pair.
> +ADD_VETH(p0, at_ns0, br-underlay, "fc00:100::1/96", [], [], nodad)
> +AT_CHECK([ip addr add dev br-underlay "fc00:100::100/96" nodad])
> +AT_CHECK([ip link set dev br-underlay up])
> +
> +dnl Set up tunnel endpoints on OVS outside the namespace and with a native
> +dnl linux device inside the namespace.
> +ADD_OVS_TUNNEL6([ip6gretap], [br0], [at_gretap0], [fc00:100::1], [10.1.1.100/24],
> +                [])
> +ADD_NATIVE_TUNNEL6([ip6gretap], [ns_gretap0], [at_ns0], [fc00:100::100],
> +                   [10.1.1.1/24], [local fc00:100::1])
> +
> +OVS_WAIT_UNTIL([ip netns exec at_ns0 ping6 -c 2 fc00:100::100])
> +
> +dnl First, check the underlay
> +NS_CHECK_EXEC([at_ns0], [ping6 -q -c 3 -i 0.3 -w 2 fc00:100::100 | FORMAT_PING], [0], [dnl
> +3 packets transmitted, 3 received, 0% packet loss, time 0ms
> +])
> +
> +dnl Okay, now check the overlay with different packet sizes
> +NS_CHECK_EXEC([at_ns0], [ping -q -c 3 -i 0.3 -w 2 10.1.1.100 | FORMAT_PING], [0], [dnl
> +3 packets transmitted, 3 received, 0% packet loss, time 0ms
> +])
> +OVS_TRAFFIC_VSWITCHD_STOP
> +AT_CLEANUP
> +
> +
>   AT_SETUP([datapath - ping over erspan v1 tunnel])
>   OVS_CHECK_KERNEL_EXCL(3, 10, 4, 15)
>   OVS_CHECK_GRE()
> diff --git a/tests/tunnel-push-pop-ipv6.at b/tests/tunnel-push-pop-ipv6.at
> index cbdd5a32f719..07dd6ab504a0 100644
> --- a/tests/tunnel-push-pop-ipv6.at
> +++ b/tests/tunnel-push-pop-ipv6.at
> @@ -1,5 +1,73 @@
>   AT_BANNER([tunnel_push_pop_ipv6])
>   
> +AT_SETUP([tunnel_push_pop_ipv6 - ip6gretap])
> +
> +OVS_VSWITCHD_START([add-port br0 p0 -- set Interface p0 type=dummy ofport_request=1 other-config:hwaddr=aa:55:aa:55:00:00])
> +AT_CHECK([ovs-vsctl add-br int-br -- set bridge int-br datapath_type=dummy], [0])
> +AT_CHECK([ovs-vsctl add-port int-br t2 -- set Interface t2 type=ip6gretap \
> +                       options:remote_ip=2001:cafe::92 ofport_request=2\
> +                       ], [0])
> +
> +AT_CHECK([ovs-appctl dpif/show], [0], [dnl
> +dummy at ovs-dummy: hit:0 missed:0
> +  br0:
> +    br0 65534/100: (dummy-internal)
> +    p0 1/1: (dummy)
> +  int-br:
> +    int-br 65534/2: (dummy-internal)
> +    t2 2/6: (ip6gretap: remote_ip=2001:cafe::92)
> +])
> +
> +dnl First setup dummy interface IP address, then add the route
> +dnl so that tnl-port table can get valid IP address for the device.
> +AT_CHECK([ovs-appctl netdev-dummy/ip6addr br0 2001:cafe::88/24], [0], [OK
> +])
> +AT_CHECK([ovs-appctl netdev-dummy/ip4addr br0 1.1.2.88/24], [0], [OK
> +])
> +AT_CHECK([ovs-appctl ovs/route/add 2001:cafe::92/24 br0], [0], [OK
> +])
> +
> +AT_CHECK([ovs-ofctl add-flow br0 action=normal])
> +
> +dnl Check Neighbour discovery.
> +AT_CHECK([ovs-vsctl -- set Interface p0 options:pcap=p0.pcap])
> +
> +AT_CHECK([ovs-appctl netdev-dummy/receive int-br 'in_port(2),eth(src=aa:55:aa:55:00:00,dst=f8:bc:12:ff:ff:ff),eth_type(0x0800),ipv4(src=1.1.3.92,dst=1.1.3.88,proto=1,tos=0,ttl=64,frag=no),icmp(type=0,code=0)'])
> +AT_CHECK([ovs-pcap p0.pcap > p0.pcap.txt 2>&1])
> +
> +AT_CHECK([cat p0.pcap.txt | grep 92aa55aa55000086dd6000000000203aff2001cafe | uniq], [0], [dnl
> +3333ff000092aa55aa55000086dd6000000000203aff2001cafe000000000000000000000088ff0200000000000000000001ff00009287004d48000000002001cafe0000000000000000000000920101aa55aa550000
> +])
> +
> +dnl
> +AT_CHECK([ovs-appctl netdev-dummy/receive p0 'in_port(1),eth(src=f8:bc:12:44:34:b6,dst=aa:55:aa:55:00:00),eth_type(0x86dd),ipv6(src=2001:cafe::92,dst=2001:cafe::88,label=0,proto=58,tclass=0,hlimit=255,frag=no),icmpv6(type=136,code=0),nd(target=2001:cafe::92,sll=00:00:00:00:00:00,tll=f8:bc:12:44:34:b6)'])
> +
> +AT_CHECK([ovs-appctl tnl/arp/show | tail -n+3 | sort], [0], [dnl
> +2001:cafe::92                                 f8:bc:12:44:34:b6   br0
> +])
> +
> +AT_CHECK([ovs-appctl tnl/ports/show |sort], [0], [dnl
> +Listening ports:
> +ip6gretap_sys (6) ref_cnt=1
> +])
> +
> +dnl Check IPv6 GRE tunnel pop
> +AT_CHECK([ovs-appctl ofproto/trace ovs-dummy 'in_port(1),eth(src=f8:bc:12:44:34:b6,dst=aa:55:aa:55:00:00),eth_type(0x86dd),ipv6(src=2001:cafe::92,dst=2001:cafe::88,label=0,proto=47,tclass=0x0,hlimit=64)'], [0], [stdout])
> +AT_CHECK([tail -1 stdout], [0],
> +  [Datapath actions: tnl_pop(6)
> +])
> +
> +dnl Check IPv6 GRE tunnel push
> +AT_CHECK([ovs-ofctl add-flow int-br action=2])
> +AT_CHECK([ovs-appctl ofproto/trace ovs-dummy 'in_port(2),eth(src=f8:bc:12:44:34:b6,dst=aa:55:aa:55:00:01),eth_type(0x0800),ipv4(src=1.1.3.88,dst=1.1.3.112,proto=47,tos=0,ttl=64,frag=no)'], [0], [stdout])
> +
> +AT_CHECK([tail -1 stdout], [0],
> +  [Datapath actions: clone(tnl_push(tnl_port(6),header(size=58,type=109,eth(dst=f8:bc:12:44:34:b6,src=aa:55:aa:55:00:00,dl_type=0x86dd),ipv6(src=2001:cafe::88,dst=2001:cafe::92,label=0,proto=47,tclass=0x0,hlimit=64),gre((flags=0x0,proto=0x6558))),out_port(100)),1)
> +])
> +
> +OVS_VSWITCHD_STOP
> +AT_CLEANUP
> +
>   AT_SETUP([tunnel_push_pop_ipv6 - ip6erspan])
>   
>   OVS_VSWITCHD_START([add-port br0 p0 -- set Interface p0 type=dummy ofport_request=1 other-config:hwaddr=aa:55:aa:55:00:00])

Works for me. Thanks!

However, do we want to keep a separate configuration for IPv6 GRE vs 
IPv4 GRE? if so, some more documentation should be adapted, for example 
vswitchd/vswitch.xml make "gre" for IPv4 and not IPv4/IPv6, and more 
places add ip6gretap as a legitimate tunnel.

Alternatively, we can maybe detect the options:remote_ip to be an 
IPv4/IPv6 address in type=gre and do the proper adjustments behind the 
scenes.

What do you think?



More information about the dev mailing list