I am replying to myself here because I've noticed something that I've missed
before.
This is a reply that has both 100 Continue AND final response (200 OK). It looks like
Kamailio's HTTP parser chokes on this type.
https://http.dev/100 says that
"HTTP response status code 100 Continue is one of the informational HTTP responses
returned by the server. It indicates that the HTTP session is progressing as expected and
is asking the client to continue to the next step. The client can safely ignore this HTTP
response if the HTTP request is complete."
I assume (didn't check yet) that Kamailio is sending headers+body, therefore the
request is complete, so the 100 Continue should be ignored and the parsing should start
from 200 OK.
Is this correct?