BIRD 3.2.1, 3.1.6, 2.18.1, and 2.17.4 released

[Ondřej Caletka]

Hello Maria,

thanks for the release. I was wondering whether there will be some 
Easter egg in it. I believe I found one :)

On 05/04/2026 21:10, Maria Matejka via Bird-users wrote:
> There is the ASPA fix you are waiting for, fixing broken downstream 
> validation. Thanks for reporting and contributing; that was a stupid 
> mistake. More on that hopefully at RIPE 92 in Edinburgh.

Looking forward for that presentation.

I tried downstream ASPA validation in BIRD 3.2.1. The good news is that 
it does not mark valid or unknown paths as invalid.

The not so good news is that is marks some unknown paths as valid. I 
peeked into the source code again and thanks to the extensive 
documentation, it is obvious where the error is and why it manifests on 
paths like this one:

1.1.1.0/24           unicast [peer_as3333_eqix3_v4 2026-04-07] * (100) 
[AS13335i]
         bgp_path: 3333 13335
         valid_roa: 1
         valid_aspa: 1

There is no ASPA for either of the ASNs, so the algorithm ends with 
min_up = 1 and min_down = 0 as it is the untouched initial state.

This means that the condition (min_up <= min_down + !force_upstream) is 
fulfilled and path is considered valid.

At least this kind of error is pretty harmless for the time being, it 
only skews the statistics a bit.

--
Best regards,

Ondřej Caletka