srv6: T6984: add locator format configuration

[jvoss]

Change Summary

Add the format configuration option to segment-routing SRv6 locators

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

• https://vyos.dev/T6984

Related PR(s)

Component(s) name

segment-routing, srv6

Proposed changes

Add a new configuration option to specify the format of the SRv6 locator. This option in FRR is useful when using uSIDs with 32-bit block and 16-bit node (3216) allocations.

VyOS configuration example:

protocols {
  segment-routing {
    srv6 {
       locator MAIN {
           behavior-usid
           block-len 32
           format usid-f3216      <<< new option
           func-bits 16
           node-len 16
           prefix fdff:0:1::/48
       }
    }
  }
}

Resulting FRR configuration:

!
segment-routing
 srv6
  locators
   locator MAIN
    prefix fdff:0:1::/48 block-len 32 node-len 16 func-bits 16
    behavior usid
    format usid-f3216
    exit
    !
  exit
  !
exit
!

How to test

1. Apply the configuration example shown above
2. Verify the rendered configuration (/run/frr/config/vyos.frr.conf) includes the format option as shown in the FRR configuration above
3. Verify the FRR running configuration contains the same format option (vtysh -c "show run")

Smoketest result

vyos@vyos:~$ /usr/libexec/vyos/tests/smoke/cli/test_protocols_segment-routing.py
test_srv6 (__main__.TestProtocolsSegmentRouting.test_srv6) ... ok
test_srv6_sysctl (__main__.TestProtocolsSegmentRouting.test_srv6_sysctl) ... ok

----------------------------------------------------------------------
Ran 2 tests in 44.963s

OK

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[github-actions]

👍
No issues in PR Title / Commit Title

[dmbaturin]

Looks good but I'd remove some superfluous words from help strings.

[jvoss]

Looks good but I'd remove some superfluous words from help strings.

No problem. They were verbatim copies from the help strings in FRR.

fyi - manually squashed these suggestions into a single commit since GitHub did not let me batch them.

[c-po]

Can you please extend the smoketests to aso cover the format CLI option?

[jvoss]

Can you please extend the smoketests to aso cover the format CLI option?

Done (see updated PR summary for smoketest results).
Note that ruff required additional changes tosmoketest/scripts/cli/test_protocols_segment-routing.py

[jvoss]

FYI - rebased on current (ec80c75) to resolve merge conflict.

[github-actions]

CI integration ❌ failed!

Details

CI logs

• CLI Smoketests (no interfaces) ❌ failed
• CLI Smoketests (interfaces only) ❌ failed
• Config tests 👍 passed
• RAID1 tests 👍 passed
• TPM tests 👍 passed