Prefix ID is Out of Range under Advanced Configuration Mode

[aque]

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Describe the bug

I get a "You specified an IPv6 prefix ID that is out of range." error on interfaces with Prefix ID > 0x0, even though the WAN is delegated a /62 prefix. This is caused by dhcp6-ia-pd-len == 0. In Basic DHCPv6 configuration mode, changing "Prefix delegation size" affects dhcp6-ia-pd-len, but I could not find an equivalent under Advanced configuration.

I checked 23.1.11 and 23.7.2, and both versions are affected.

To Reproduce

Steps to reproduce the behavior:

1. Set DHCPv6 Configuration Mode to Basic
2. Set Prefix delegation size to 64
3. Apply config
4. Set DHCPv6 Configuration Mode to Advanced
5. Configure IPv6 PD for a /62 prefix
   • Send Options: ia-pd 0
   • Prefix Delegation: CHECK
   • id-assoc pd ID: 0
   • Prefix: 2603:3018:xxxx:xx34::/62
   • Preferred Lifetime: infinity
   • Prefix Interface Site-Level Aggregation Length: 2
6. Apply config
7. Configure LAN interface to Track WAN using Prefix ID 0x2 (2603:3018:xxxx:xx36::/64)
8. Error pops up when attempting to save

Expected behavior

Prefix ID 0x2 on LAN is acceptable with a /62 PD under Advanced configuration mode. dhcp6-ia-pd-len is set to 2.

Describe alternatives you considered

Two workarounds:

1. Download config.xml and set <dhcp6-ia-pd-len> to the correct value (2).
2. Switch WAN Configuration Mode to Basic and change "Prefix delegation size" to the proper value (/62). Then, switch back to Advanced.

Possible solution: If configuration mode is Advanced, adv_dhcp6_prefix_interface_statement_sla_len could set dhcp6-ia-pd-len. It would have a value of 0 if adv_dhcp6_prefix_interface_statement_sla_len is blank.

Additional context

Advanced Configuration Mode is required to request a specific IPv6 prefix.

Environment

Lab is VMware: OPNsense 23.1.11_1-amd64 FreeBSD 13.1-RELEASE-p8 OpenSSL 1.1.1u 30 May 2023 em interface driver

Production is bare metal: OPNsense 23.7.2-amd64 FreeBSD 13.2-RELEASE-p2 OpenSSL 1.1.1v 1 Aug 2023 igb interface driver

[fichtner]

@aque thanks for the report. Does this help? 819689d

Cheers, Franco

[aque]

Thanks @fichtner for looking into this and for that quick fix. I loaded it into my lab and it is working. Is this issue safe to close, or do you prefer to keep it open until released?

[fichtner]

Safe to close. I’ll add this to 23.7.4 because 23.7.3 comes out today already.

Cheers, Franco