[lwip-devel] [bug #20595] LWIP IGMP ignores IGMP v3 packets

[INVALID.NOREPLY]

URL:
  <http://savannah.nongnu.org/bugs/?20595>

                 Summary: LWIP IGMP ignores IGMP v3 packets 
                 Project: lwIP - A Lightweight TCP/IP stack
            Submitted by: thedoctor
            Submitted on: Thursday 26/07/07 at 14:57
                Category: None
                Severity: 3 - Normal
              Item Group: Faulty Behaviour
                  Status: None
                 Privacy: Public
             Assigned to: None
             Open/Closed: Open
         Discussion Lock: Any
         Planned Release: 

    _______________________________________________________

Details:

LWIP IGMP discards IGMP v3 query messages because it does not check the
checksum over the entire PDU as required by RFC2236 clause 2.3. Instead it
assumes the PDU is only 8 bytes long.

Note that an IGMP v3 query message is the same as an IGMP v2 query but has
additional fields after the Group Address (See RFC3376 clause 4.1). These
additional fields are included in the checksum. 

My suggested fix is attached. I've tested it and it works.



    _______________________________________________________

File Attachments:


-------------------------------------------------------
Date: Thursday 26/07/07 at 14:57  Name: igmp.c.patch  Size: 1kB   By:
thedoctor
Correct IGMP sumcheck validation
<http://savannah.nongnu.org/bugs/download.php?file_id=13478>

    _______________________________________________________

Reply to this item at:

  <http://savannah.nongnu.org/bugs/?20595>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.nongnu.org/