Ethereal-dev: [Ethereal-dev] Decoding problem for GTPv1

Note: This archive is from the project's previous web site, ethereal.com. This list is no longer active.

From: "Wuttichai Wutti-Udomlert (DU/EDD)" <wuttichai.wutti-udomlert@xxxxxxxxxxxx>
Date: Thu, 11 Sep 2003 14:42:13 +0200
Hello,

I'm using Ethereal version 0.9.14 and 0.9.15 on Windows2000 for capturing GTPv1 protocol.  By the way, it is not possible to decode in some message.  Are there any posibility to decode the message correctly?  I've attach the example below.

BR/Wuttichai


*********************************************************

GPRS Tunnelling Protocol v1
    Flags: 0x32
        001. .... = Version: GTP release 99 version (1)
        ...1 .... = Protocol type: 1
        .... 0... = Spare bit: 0
        .... .0.. = Is Next Extension Header present?: no
        .... ..1. = Is Sequence Number present?: yes
        .... ...0 = Is N-PDU number present?: no
    Message Type: SGSN context response (0x33)
    Length: 482
    TEID: 0x000163b1
    Sequence Number: 0x07fe
    N-PDU Number: 0xff
    Next extension header type: 0x00
    [--- end of GTP v1 header, beginning of extension headers ---]
    Cause : Request accepted (128)
    IMSI: 214011500001004
    TEID Control Plane: 0x000000ed
    Radio Priority for NSAPI(80) : 1
    0101 .... = NSAPI in Radio Priority: 5
    .... 0... = Reserved: 0
    .... .001 = Radio Priority: 1
    MM context
        Length: 153
        Ciphering Key Sequence Number: 5
        Security type: 2 (UMTS key and quintuplets)
        No of triplets: 4
        Ciphering key CK: 2B975F90DB06754E93FF6ADAC25AC20A
        Integrity key CK: A63A691CBFC3116455BDF8B01E2EDC61
        Quintuplets length: 128
        Quintuplet #0
            Length: 1b34
            RAND: 0AE1A8630346FF59FF1C99230095088F
            XRES length: 15696
[Malformed Packet: GTPv1]