[SR-Users] decode_mime_type error

[Bucur Marius]

Hello Jijo,

It seems like the decode_mime_type is a somehow broken. The comma is very well allowed in boundary, as you said. The BNF specified in RFC2046 permits it.
But, the decode_mime_type function ignores everything coming after comma. More than that, it notifies the function caller that this content type has multiple mime types.
I think the author of the function thought of something like:

Content-Type: text/html, image/jpeg // very weird, though

This is wrong, hence the comma can be in a parameter (like in your case).
I think the best fix, as you said is to remove that check, hence a non-NULL return value doesn't mean anything (that the content type has multiple mime types).
Another fix is to write a "good" decode_mime_type, that checks if the comma is inside a parameter. I don't know if effort is worth it.

One thing we need to do is to check if there are any functions in Kamailio that call decode_mime_type and also perform this check (ret != end).

Cheers,
Marius


________________________________
From: Jijo <realjijo at gmail.com>
To: sr-users at lists.sip-router.org; sr-dev at lists.sip-router.org
Sent: Wednesday, August 17, 2011 10:54 AM
Subject: [SR-Users] decode_mime_type error


Hi All,

The function parse_content_type_hdr() is failing in decode_mime_type() when Content-Type parameter "boundary" has value comma as below. The error message is "ERROR:parse_content_type_hdr: CONTENT_TYPE hdr contains "
            "more then one mime type :-(!

Content Type Header is as below, It works fine if the boundary value is without comma.

Content-Type: multipart/mixed;boundary=",AW"

The parse_content_type_hdr() is failing in the following code,

    ret = decode_mime_type(msg->content_type->body.s, end , &mime);
    if (ret==0)
        goto error;
    if (ret!=end) {

         LOG(L_INFO,"ERROR:parse_content_type_hdr: CONTENT_TYPE hdr contains "
            "more then one mime type :-(!\n");
           goto error ; 
    }

I thought of fixing this issue by commenting the code for condition ret !=end. I'm  not sure why we we need that check, as mime variable has the information to process the content.

Please let me know if you see any impact.

Thanks
Jijo





_______________________________________________
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
sr-users at lists.sip-router.org
http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users