This is merely a historical archive of years 2008-2021, before the migration to mailman3.
A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/osmocom-net-gprs@lists.osmocom.org/.
Steve Markgraf steve at steve-m.deHi,
I noticed a bug in the dissector, which seems to happen when then
Exist_A5_bits field is set to 0, and results in the following fields
(Exist_Multislot_capability/Exist_GPRS_multislot_class) being decoded
incorrectly. Thus, get_ms_class_by_capability() is returning NULL
instead of the GPRS_multislot_class, which is interestingly dissected
correctly.
This is one of the messages where this happens:
4017dfb83a3f628a7045500898f28109100297e0080b2b
If I add it to the RLCMACTest it fails, so I propose it should be added
;)
My quite recent version of Wireshark (1.8.2) is decoding this message
fine, see the attachment. I've gone through the recent changes on
packet-gsm_rlcmac.c and packet-csn1.c in Wireshark, but couldn't spot
the commit that fixed it so far.
Regards,
Steve
-------------- next part --------------
raw bytes: 4017dfb83a3f628a7045500898f28109100297e0080b2b
GSM RLC/MAC: PACKET_RESOURCE_REQUEST (Uplink)
01.. .... = PayloadType: 1
..00 000. = spare: 0
.... ...0 = R: 0
0001 01.. = MESSAGE_TYPE: 5
.... ..1. Exist_ACCESS_TYPE
.... ...1 1... .... = ACCESS_TYPE: 3
ID
.1.. .... Choice: PacketResourceRequestID (1)
PacketResourceRequestID
..01 1111 1011 1000 0011 1010 0011 1111 01.. .... = TLLI: 2128668925
..1. .... Exist_MS_Radio_Access_capability
MS_Radio_Access_capability
MS_RA_capability_value[0]
...0 001. Choice: MS_RA_capability_value_Choice (1)
MS_RA_capability_value_Choice
.... ...0 1000 10.. u.Content length: 34
u.Content
.... ..10 0... .... = RF_Power_Capability: 4
.1.. .... Exist_A5_bits
..11 0000 0... .... = A5_bits: 96
.1.. .... = ES_IND: 1
..0. .... = PS: 0
...0 .... = VGCS: 0
.... 0... = VBS: 0
.... .1.. Exist_Multislot_capability
Multislot_capability
.... ..0. Exist_HSCSD_multislot_class
.... ...1 Exist_GPRS_multislot_class
0101 0... = GPRS_multislot_class: 10
.... .0.. = GPRS_Extended_Dynamic_Allocation_Capability: 0
.... ..0. Exist_SM
.... ...0 Exist_ECSD_multislot_class
0... .... Exist_EGPRS_multislot_class
.0.. .... Exist_DTM_GPRS_multislot_class
..0. .... Exist_Eight_PSK_Power_Capability
...0 .... = COMPACT_Interference_Measurement_Capability: 0
.... 1... = Revision_Level_Indicator: 1
.... .0.. = UMTS_FDD_Radio_Access_Technology_Capability: 0
.... ..0. = UMTS_384_TDD_Radio_Access_Technology_Capability: 0
.... ...0 = CDMA2000_Radio_Access_Technology_Capability: 0
[NULL data]: UMTS_128_TDD_Radio_Access_Technology_Capability Not Present
[NULL data]: GERAN_Feature_Package_1 Not Present
[NULL data]: Modulation_based_multislot_class_support Not Present
[NULL data]: GMSK_MultislotPowerProfile Not Present
[NULL data]: EightPSK_MultislotProfile Not Present
[NULL data]: MultipleTBF_Capability Not Present
[NULL data]: DownlinkAdvancedReceiverPerformance Not Present
[NULL data]: ExtendedRLC_MAC_ControlMessageSegmentionsCapability Not Present
[NULL data]: DTM_EnhancementsCapability Not Present
[NULL data]: PS_HandoverCapability Not Present
1... .... Exist:MS_RA_capability_value[1]
MS_RA_capability_value[1]
.001 1... Choice: MS_RA_capability_value_Choice (3)
MS_RA_capability_value_Choice
.... .000 1111 .... u.Content length: 15
u.Content
.... 001. = RF_Power_Capability: 1
.... ...0 Exist_A5_bits
1... .... = ES_IND: 1
.0.. .... = PS: 0
..0. .... = VGCS: 0
...0 .... = VBS: 0
.... 0... Exist_Multislot_capability
.... .0.. Exist_Eight_PSK_Power_Capability
.... ..0. = COMPACT_Interference_Measurement_Capability: 0
.... ...1 = Revision_Level_Indicator: 1
0... .... = UMTS_FDD_Radio_Access_Technology_Capability: 0
.0.. .... = UMTS_384_TDD_Radio_Access_Technology_Capability: 0
..0. .... = CDMA2000_Radio_Access_Technology_Capability: 0
[NULL data]: UMTS_128_TDD_Radio_Access_Technology_Capability Not Present
[NULL data]: GERAN_Feature_Package_1 Not Present
[NULL data]: Modulation_based_multislot_class_support Not Present
[NULL data]: GMSK_MultislotPowerProfile Not Present
[NULL data]: EightPSK_MultislotProfile Not Present
[NULL data]: MultipleTBF_Capability Not Present
[NULL data]: DownlinkAdvancedReceiverPerformance Not Present
[NULL data]: ExtendedRLC_MAC_ControlMessageSegmentionsCapability Not Present
[NULL data]: DTM_EnhancementsCapability Not Present
[NULL data]: PS_HandoverCapability Not Present
...0 .... Exist:MS_RA_capability_value[2]
Channel_Request_Description
.... 1001 = PEAK_THROUGHPUT_CLASS: 9
00.. .... = RADIO_PRIORITY: 0
..0. .... RLC_MODE
...1 .... LLC_PDU_TYPE
.... 0000 0000 0010 1001 .... = RLC_OCTET_COUNT: 41
.... 0... Exist_CHANGE_MARK
.... .111 111. .... = C_VALUE: 63
...0 .... Exist_SIGN_VAR
Slot[0]
.... 0... Exist
Slot[1]
.... .0.. Exist
Slot[2]
.... ..0. Exist
Slot[3]
.... ...0 Exist
Slot[4]
0... .... Exist
Slot[5]
.0.. .... Exist
Slot[6]
..0. .... Exist
Slot[7]
...0 .... Exist
.... 1... Exist_AdditionsR99
AdditionsR99
.... .0.. Exist_EGPRS_BEP_LinkQualityMeasurements
.... ..0. Exist_EGPRS_TimeslotLinkQualityMeasurements
.... ...0 Exist_PFI
0... .... = MS_RAC_AdditionalInformationAvailable: 0
.0.. .... = RetransmissionOfPRR: 0
Padding Bits
..00 1011 Padding