Wireshark · Wireshark-dev: [Wireshark-dev] <Help> How to add fieldname for certain IEs

[Leon Liu <leon.liu@xxxxxxxxxxxx>]

Hi all,

 

Now what I want to do is extract certain IEs(which involve MS capability) from pcap files via tshark.

In my plan, I can achieve it using command 'tshark -r filename.dump -R filter(filter out 'attach request') -T field -e fieldname'.

But when I check the fieldname of IEs which I want to extract, I found that the fieldname is null.

 

So my question is how to add fieldname in source code?

The picture below shows the stacks of protocols and the IEs within the red ellipse are what I want.

 

Could someone help me to locate which source file I need to modify? And give me an simple example of how to achieve a new field name?

Thank you

 

 

Below shows the IEs I want which are marked as red.

 

Command:

$ tshark -r gb_link1_05212010_test_00001_20100522012000.dump -R gsm_a.dtap_msg_

gmm_type==0x1 -T pdml | less

 

 

    <field name="" show="MS Radio Access Capability" size="11" pos="91" value="0

a1453c32b2044c7960800">

      <field name="gsm_a.len" showname="Length: 10" size="1" pos="91" show="10"

value="0a"/>

      <field name="" show="MS RA capability 1" size="5" pos="92" value="1453c32b

20">

        <field name="gsm_a.gm.acc_tech_type" showname="0001 .... = Access Techno

logy Type: GSM E --note that GSM E covers GSM P (1)" size="1" pos="92" show="1"

value="14"/>

        <field name="gsm_a.gm.acc_cap_struct_len" showname=".... 0100  010. ....

= Length in bits: 0x22 (34)" size="2" pos="92" show="0x22" value="1453"/>

        <field name="" show="...1 00.. RF Power Capability, GMSK Power Class: 2

W (33 dBm) (4)" size="1" pos="93" value="53"/>

        <field name="" show="A5 Bits: A5 bits follow (1)" size="1" pos="93" valu

e="53"/>

        <field name="" show="A5/1: encryption algorithm available (1)" size="1"

pos="93" value="53"/>

        <field name="" show="A5/2: encryption algorithm available (1)" size="1"

pos="94" value="c3"/>

        <field name="" show="A5/3: encryption algorithm available (1)" size="1"

pos="94" value="c3"/>

        <field name="" show="A5/4: encryption algorithm not available (0)" size=

"1" pos="94" value="c3"/>

        <field name="" show="A5/5: encryption algorithm not available (0)" size=

"1" pos="94" value="c3"/>

        <field name="" show="A5/6: encryption algorithm not available (0)" size=

"1" pos="94" value="c3"/>

        <field name="" show="A5/7: encryption algorithm not available (0)" size=

"1" pos="94" value="c3"/>

        <field name="" show="Controlled early Classmark Sending: controlled earl

y Classmark Sending option is implemented (1)" size="1" pos="94" value="c3"/>

        <field name="" show="Pseudo Synchronisation: PS capability present (1)"

size="1" pos="94" value="c3"/>

        <field name="" show="Voice Group Call Service: no VGCS capability or no

notifications wanted (0)" size="1" pos="95" value="2b"/>

        <field name="" show="Voice Broadcast Service: no VBS capability or no no

tifications wanted (0)" size="1" pos="95" value="2b"/>

        <field name="" show="Multislot capability: Multislot capability struct a

vailable (1)" size="1" pos="95" value="2b"/>

        <field name="" show="HSCSD multislot class: Bits are not available (0)"

size="1" pos="95" value="2b"/>

        <field name="" show="GPRS multislot class: Max Rx-Slot/TDMA:4 Max Tx-Slo

t/TDMA:4 Max-Sum-Slot/TDMA:5 Tta:2 Ttb:1 Tra:2 Trb:1 Type:1 (12)" size="2" pos="

95" value="2b20"/>

        <field name="" show="GPRS Extended Dynamic Allocation Capability: Extend

ed Dynamic Allocation Capability for GPRS is implemented (1)" size="1" pos="96"

value="20"/>

        <field name="" show="SMS/SM values: Bits are not available (0)" size="1"

pos="96" value="20"/>

        <field name="" show="ECSD multislot class: Bits are not available (0)" s

ize="1" pos="96" value="20"/>

        <field name="" show="EGPRS multislot class: Bits are not available (0)"

size="1" pos="96" value="20"/>

        <field name="" show="DTM GPRS Multi Slot Class: Bits are not available (

0)" size="1" pos="96" value="20"/>

        <field name="" show="8PSK Power Capability: Bits are not available (0)"

size="1" pos="96" value="20"/>

        <field name="" show="COMPACT Interference Measurement Capability: COMPAC

T Interference Measurement Capability is not implemented (0)" size="1" pos="97"

value="44"/>

        <field name="" show="Revision Level Indicator: The ME is Release 99 onwa

rds (1)" size="1" pos="97" value="44"/>----------------------------------------------------------------------------------------> the field names of these IEs are all null.

        <field name="" show="UMTS FDD Radio Access Technology Capability: UMTS F

DD not supported (0)" size="1" pos="97" value="44"/>

        <field name="" show="UMTS 3.84 Mcps TDD Radio Access Technology Capabili

ty: UMTS 3.84 Mcps TDD not supported (0)" size="1" pos="97" value="44"/>

        <field name="" show="CDMA 2000 Radio Access Technology Capability: CDMA

2000 not supported (0)" size="1" pos="97" value="44"/>

 

Best Regards

Leon