Wireshark-bugs: [Wireshark-bugs] [Bug 10842] Cannot dissect gtp prime data record with rel. 7.5.

Date: Tue, 13 Jan 2015 08:40:08 +0000

Comment # 4 on bug 10842 from
(In reply to Mato from comment #3)
> (In reply to Anders Broman from comment #1)
> > From what I can see the record type is:
> > 
> > ...1 0101 = Tag: 21
> > 
> > GPRSRecord	::= CHOICE 
> > --
> > -- Record values 20, 22..27 are specific
> > -- Record values 76, 77, 86 are MBMS specific
> > -- Record values 78,79 and 92, 95, 96 are EPC specific 
> > --
> > {
> > 	sgsnPDPRecord			[20] SGSNPDPRecord,
> > 	sgsnMMRecord			[22] SGSNMMRecord,
> > 
> > Which isn't specified in the ASN1 description, should it have been record
> > type 20? or what type of record is it supposed to be?
> 
> I just successfully(In reply to Anders Broman from comment #1)
> > From what I can see the record type is:
> > 
> > ...1 0101 = Tag: 21
> > 
> > GPRSRecord	::= CHOICE 
> > --
> > -- Record values 20, 22..27 are specific
> > -- Record values 76, 77, 86 are MBMS specific
> > -- Record values 78,79 and 92, 95, 96 are EPC specific 
> > --
> > {
> > 	sgsnPDPRecord			[20] SGSNPDPRecord,
> > 	sgsnMMRecord			[22] SGSNMMRecord,
> > 
> > Which isn't specified in the ASN1 description, should it have been record
> > type 20? or what type of record is it supposed to be?
> 
> I just successfully decoded contents in Wireshark 1.8.10 as:
>    GPRSCallEventRecord: ggsnPDPRecord (21)
>      recordType: ggsnPDPRecord (19)

Ok, the current code in packet-gtp.c is
            if(format==1) {
                if(rel_id == 6){
                    dissect_gprscdr_GPRSCallEventRecord_PDU(next_tvb, pinfo,
cdr_dr_tree, NULL);
                }else if(rel_id >6){
                    dissect_gprscdr_GPRSRecord_PDU(next_tvb, pinfo,
cdr_dr_tree, NULL);
                }
If I remember correctly the spec at some point changed the naming from
GPRSCallEventRecord to GPRSRecord and apparently the defentions changed. So
either your rel_id does not fit the CDR format or Wiresharks code is wrong :-)
(I'm not sure when I'll have the time to check which one it is).


You are receiving this mail because:
  • You are watching all bug changes.