[OVN] classless-static-route DHCP option is not sanitized and overrides default routes

[Lucas Alvares Gomes]

Reported at: https://bugzilla.redhat.com/show_bug.cgi?id=2283515

extra-dhcp-option classless-static-route is not working properly. It sets the value in the SBDB without {} and overrides default routes.

Steps to Reproduce:

1. after port creation:
~~~
ovn-sbctl --db=$SBDB find logical_flow external_ids:stage-name=ls_in_dhcp_options | grep -B 2 -A 6 192.168.210.114
_uuid : 57c306d2-5e5b-460b-b314-9e581bb44e12
actions : "reg0[3] = put_dhcp_opts(offerip = 192.168.210.114, classless_static_route = {169.254.169.254/32,192.168.210.100, 0.0.0.0/0,192.168.210.1}, dns_server = {172.16.0.1, 10.0.0.1}, lease_time = 43200, mtu = 1442, netmask = 255.255.255.0, router = 192.168.210.1, server_id = 192.168.210.1); next;"
--
_uuid : cbe4a7b9-6536-4a28-833c-b941eecd7886
actions : "reg0[3] = put_dhcp_opts(offerip = 192.168.210.114, classless_static_route = {169.254.169.254/32,192.168.210.100, 0.0.0.0/0,192.168.210.1}, dns_server = {172.16.0.1, 10.0.0.1}, lease_time = 43200, mtu = 1442, netmask = 255.255.255.0, router = 192.168.210.1, server_id = 192.168.210.1); next;"
~~~

2. then if we set a set static route:
~~~
openstack port set --extra-dhcp-option name=classless-static-route,value=128.128.128.128/32,22.2.0.2,ip-version=4 a02943c7-6761-43ed-bcfd-2ac01afd2cb8
~~~

3. We will lose the default static route and it creates a syntax error because remove the {}
~~~
[root@compute-1 /]# ovn-sbctl --db=$SBDB find logical_flow external_ids:stage-name=ls_in_dhcp_options | grep -B 2 -A 6 192.168.210.114

_uuid : 8ead0f38-60fa-4d4e-88d1-63c39a03563f
actions : "reg0[3] = put_dhcp_opts(offerip = 192.168.210.114, classless_static_route = 128.128.128.128/32,22.2.0.2, dns_server = {172.16.0.1, 10.0.0.1}, lease_time = 43200, mtu = 1442, netmask = 255.255.255.0, router = 192.168.210.1, server_id = 192.168.210.1); next;"
--
_uuid : 36084950-18f7-4c41-9142-e34abdae4094
actions : "reg0[3] = put_dhcp_opts(offerip = 192.168.210.114, classless_static_route = 128.128.128.128/32,22.2.0.2, dns_server = {172.16.0.1, 10.0.0.1}, lease_time = 43200, mtu = 1442, netmask = 255.255.255.0, router = 192.168.210.1, server_id = 192.168.210.1); next;"
~~~

4. we can see the syntax error in the logs:
~~~
2024-05-27T08:53:12.951Z|328987|lflow|WARN|error parsing actions "reg0[3] = put_dhcp_opts(offerip = 192.168.210.114, classless_static_route = 128.128.128.128/32,22.2.0.2, dns_server = {192.168.210.212, 192.168.210.213}, lease_time = 43200, mtu = 1500, netmask = 255.255.255.0, router = 192.168.210.1, server_id = 192.168.210.1, tftp_server_address = 10.0.0.1); next;": Syntax error at `22.2.0.2'.
~~~

as a Workaround I pass the static route with the default ones in the {}, something like:
~~~
openstack port set --extra-dhcp-option name=classless-static-route,value="{169.254.169.254/32,192.168.210.100,0.0.0.0/0,192.168.210.1,128.128.128.128/32,22.2.0.2},ip-version=4" a02943c7-6761-43ed-bcfd-2ac01afd2cb8
~~~

ML2/OVN should not only sanitize this option (e.g making sure that it's wrapped with {} as expected by OVN) but also merge both the user routes and the default routers that comes from the subnet.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/neutron/+/922119

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/neutron/+/922119
Committed: https://opendev.org/openstack/neutron/commit/ceee380a1835d706579aa0f3597ad9e0ce1a37ee
Submitter: "Zuul (22348)"
Branch: master

commit ceee380a1835d706579aa0f3597ad9e0ce1a37ee
Author: Lucas Alvares Gomes <email address hidden>
Date: Mon Jun 17 13:53:04 2024 +0100

    [OVN] Sanitize the classless-static-route DHCP option

    This patch ensures that the "classless-static-route" is wrapped in {} as
    expected by OVN and also merges the default routes with the user
    inputted ones so everything works as expected.

    Closes-Bug: #2069625
    Change-Id: I302a872161c55df447a05b31d99c702537502a2f
    Signed-off-by: Lucas Alvares Gomes <email address hidden>

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/2024.1
Review: https://review.opendev.org/c/openstack/neutron/+/922323

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/2023.2
Review: https://review.opendev.org/c/openstack/neutron/+/922324

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/2023.1
Review: https://review.opendev.org/c/openstack/neutron/+/922325

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/neutron/+/922323
Committed: https://opendev.org/openstack/neutron/commit/3d97c4f2ac34ee2402d1067d6828f5f3e53e713c
Submitter: "Zuul (22348)"
Branch: stable/2024.1

commit 3d97c4f2ac34ee2402d1067d6828f5f3e53e713c
Author: Lucas Alvares Gomes <email address hidden>
Date: Mon Jun 17 13:53:04 2024 +0100

    [OVN] Sanitize the classless-static-route DHCP option

    This patch ensures that the "classless-static-route" is wrapped in {} as
    expected by OVN and also merges the default routes with the user
    inputted ones so everything works as expected.

    Closes-Bug: #2069625
    Change-Id: I302a872161c55df447a05b31d99c702537502a2f
    Signed-off-by: Lucas Alvares Gomes <email address hidden>
    (cherry picked from commit ceee380a1835d706579aa0f3597ad9e0ce1a37ee)

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/neutron/+/922325
Committed: https://opendev.org/openstack/neutron/commit/0fb74dbbe1f3edb8167e591984b3593bf1bd5fbb
Submitter: "Zuul (22348)"
Branch: stable/2023.1

commit 0fb74dbbe1f3edb8167e591984b3593bf1bd5fbb
Author: Lucas Alvares Gomes <email address hidden>
Date: Mon Jun 17 13:53:04 2024 +0100

    [OVN] Sanitize the classless-static-route DHCP option

    This patch ensures that the "classless-static-route" is wrapped in {} as
    expected by OVN and also merges the default routes with the user
    inputted ones so everything works as expected.

    Closes-Bug: #2069625
    Change-Id: I302a872161c55df447a05b31d99c702537502a2f
    Signed-off-by: Lucas Alvares Gomes <email address hidden>
    (cherry picked from commit ceee380a1835d706579aa0f3597ad9e0ce1a37ee)

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/neutron/+/922324
Committed: https://opendev.org/openstack/neutron/commit/f6ec99d1b8d90010ed1bf445d6a127c900ab1892
Submitter: "Zuul (22348)"
Branch: stable/2023.2

commit f6ec99d1b8d90010ed1bf445d6a127c900ab1892
Author: Lucas Alvares Gomes <email address hidden>
Date: Mon Jun 17 13:53:04 2024 +0100

    [OVN] Sanitize the classless-static-route DHCP option

    This patch ensures that the "classless-static-route" is wrapped in {} as
    expected by OVN and also merges the default routes with the user
    inputted ones so everything works as expected.

    Closes-Bug: #2069625
    Change-Id: I302a872161c55df447a05b31d99c702537502a2f
    Signed-off-by: Lucas Alvares Gomes <email address hidden>
    (cherry picked from commit ceee380a1835d706579aa0f3597ad9e0ce1a37ee)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 25.0.0.0b1 development milestone.