bind used as resolver: matching the source ip

[pm8pm8 at t-online.de]

Dear all,
 
As far as I understand, BIND is not only used for authoritative name 
servers, but is also often used as a (recursive) resolver.
When receiving a response to a DNS query, does BIND match the source ip of 
the response to the destination ip of the query and discard the response if 
they do not match? Does it match the ports?
I.e. apart from checking
query.transactionID == response.transactionID
does BIND check for
query.destinationIP == response.sourceIP
and
query.destinationPort == response.sourcePort?
Can you point me to the function in the source code where this check does 
or does not happen?
Any help is appreciated.


<div style=\"border:0;border-bottom:1px solid black;width:100%;\"> 
Gesendet mit Telekom Mail <https://t-online.de/email-kostenlos> - kostenlos 
und sicher für alle!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.isc.org/pipermail/bind-users/attachments/20160818/0f8e5a48/attachment.html>