DHCP client/server ports incorrectly defined in constants file

[Brian Haley]

The DHCP client and server port numbers are incorrectly defined in the constants file:

DHCP_CLIENT_PORT = 67
DHCP_RESPONSE_PORT = 68

IANA defines these the opposite - 68 for the client and 67 for the server.

Neutron uses them backwards, so will also need an update to work-around so a new release of neutron-lib doesn't break things.

Also, other plugins seemed to have noticed and worked around this already, at least Dragonflow and Cisco have defined them correctly locally:

http://codesearch.openstack.org/?q=DHCP_CLIENT_PORT&i=nope&files=&repos=

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/734181

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/734182

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/734181
Committed: https://git.openstack.org/cgit/openstack/neutron-lib/commit/?id=d7900610163705a624493a9924c72abfbc338b49
Submitter: Zuul
Branch: master

commit d7900610163705a624493a9924c72abfbc338b49
Author: Brian Haley <email address hidden>
Date: Mon Jun 8 15:27:20 2020 -0400

    Correctly define DHCP port numbers for IPv4

    The client and server DHCP port numbers are opposite
    of what they should be according to the IANA definitions.

    Change-Id: Iaa74ec5d569a3dee65f7e788394ffe063748bab6
    Closes-bug: #1882588

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/738111

[OpenStack Infra (hudson-openstack)]

Change abandoned by Brian Haley (<email address hidden>) on branch: master
Review: https://review.opendev.org/738111
Reason: Squashed into https://review.opendev.org/#/c/734182/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/734182
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=0ffaac1db23d916c7a73437b13fab56bb9f6b6da
Submitter: Zuul
Branch: master

commit 0ffaac1db23d916c7a73437b13fab56bb9f6b6da
Author: Brian Haley <email address hidden>
Date: Mon Jun 8 15:29:13 2020 -0400

    Use the correct value for the DHCP client port number

    Version 2.4.0 of neutron-lib has the DHCP port numbers
    correct, so start using them.

    Also updated other code in linux/dhcp.py to use the
    constants as well, instead of re-defining them.

    Closes-bug: #1882588

    Change-Id: I5dc1d8e7bcc94efd1fab68d980d60e3130d5e5bc