[Dnsmasq-discuss] Question about tcp_request in 2.91

[Tijs Van Buggenhout]

Hi Simon,

I have a question about commit 6656790f in regard changes to tcp_request 
function.

commit 6656790f2498f2a0b21086bc4ab47a2e38429a7c
Author: Simon Kelley <simon at thekelleys.org.uk>
Date:   Tue Jan 7 20:46:33 2025 +0000

    Handle queries with EDNS client subnet fields better.

The call to add_edns0_config moved up, even before the "find_pseudoheader" 
condition that sets have_pseudoheader. To my understanding add_edns0_config 
prepares the original request to be forwarded (with regard to EDNS).
Since the function adds EDNS to the packet, the original query is altered even 
before it has been processed and decided whether to handle locally or forward, 
ie. it invalidates "have_pseudoheader".

The general logic in receive_query differs from tcp_request:

1. checks
2. find_pseudoheader
3. flags
4. answer : {disallowed,auth, saved_question + request (from cache)} => send
5. forward if not (local) answered

vs

1. checks
2. saved_question
3. find_pseudoheader
4. flags
5. answer : {disallowed,auth,request (from cache)} => send
6. forward if not (local) answered

Kind regards,
Tijs
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: This is a digitally signed message part.
URL: <http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/attachments/20250228/bf50dd59/attachment.sig>