T6100: Added NAT migration from IP/Netmask to Network/Netmask (backport #3291)

[mergify]

Change Summary

Added NAT migration from IP/Netmask to Network/Netmask.
In 1.3 allowed using IP/Netmask in Nat rules.
In 1.4 and 1.5 it is prohibited. Allowed Network/Netmask.

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/T6100

Related PR(s)

Component(s) name

nat

Proposed changes

Added NAT migration from IP/Netmask to Network/Netmask.
In 1.3 allowed using IP/Netmask in Nat rules.
In 1.4 and 1.5 it is prohibited. Allowed Network/Netmask.

How to test

For example:
VyOS 1.3.6 configuration:

set nat destination rule 2060 destination port '5060,10000-20000'
set nat destination rule 2060 inbound-interface 'eth4'
set nat destination rule 2060 protocol 'udp'
set nat destination rule 2060 source address '!192.0.2.226/27'
set nat destination rule 2060 translation address '10.250.1.3'

Netfilter config in 1.3.6

table ip nat {
        chain PREROUTING {
                type nat hook prerouting priority dstnat; policy accept;
                counter packets 411 bytes 72404 jump VYATTA_PRE_DNAT_HOOK
                iifname "eth4" meta l4proto udp ip saddr != 192.0.2.224/27 udp dport { 5060,10000-20000} counter packets 0 bytes 0 dnat to 10.250.1.3 comment "DST-NAT-2060"
        }

Migration to 1.4 or 1.5 fails, because

vyos@vyos# set nat destination rule 2060 source address '!192.0.2.226/27'

  Error: 192.0.2.226/27 is not a valid IPv4 address range

  Error: 192.0.2.226/27 is not a valid IPv4 prefix

  Error: 192.0.2.226/27 is not a valid IPv4 address

  Error: !192.0.2.226/27 is not a valid IPv4 address range

  Error: !192.0.2.226/27 is not a valid IPv4 prefix

  Error: !192.0.2.226/27 is not a valid IPv4 address



  Invalid value
  Value validation failed
  Set failed

[edit]

After changes:
After migration from 1.3 to 1.4 or 1.5. VyOS config looks

set nat destination rule 2060 destination port '5060,10000-20000'
set nat destination rule 2060 inbound-interface name 'eth4'
set nat destination rule 2060 protocol 'udp'
set nat destination rule 2060 source address '!192.0.2.224/27'
set nat destination rule 2060 translation address '10.250.1.3'

Smoketest result

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

---

This is an automatic backport of pull request #3291 done by [Mergify](https://mergify.com).