Hi,
Now, does this mean that we also need to restrict what kind of message
body types we allow in INVITE, re-INVITE and UPDATE?
Not really. INVITE means something: it means "I'm trying to set up a
session, and here's a description of that session." The first half ("I'm
trying to set up a session") has specific semantics associated with it. The
second half ("here's a description of that session") tells you exactly what
goes in the body.
INFO just says "Here's a framed chunk of data."
There is no valid comparison between the two.
I agree that the semantics of the commands are different. However, one IS
allowed to include any kind of message body in the INVITE request, to provide
whatever "extra information" about the session (text, HTML, whatever...), so
someone could argue that whatever stuff they put into the INVITE does provide
"extra information" about the session...
There is a huge difference that you are ignorning.