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Diffstat (limited to 'README')
| -rw-r--r-- | README | 32 |
1 files changed, 32 insertions, 0 deletions
@@ -9,3 +9,35 @@ the necessary utility. In general all Qualcomm devices that export DIAG should be supported. We have tested it with the Quectel UC20, EC20 and EC25 devices. + +The convenient way to create a pcap dump of the messages is to run +capture.sh -s /dev/ttyUSB0 -G +This requires tcpdump, as well as the required permissions +to capture, i.e. on ubuntu this can be conveniently achieved by +sudo setcap cap_net_raw,cap_net_admin=ep /usr/sbin/tcpdump + +Additionally wireshark needs Edit->Preferences->Protocols->NAS-EPS +"Force dissect as plain EPS" set to true, since capturing encrypted NAS +messages is fairly useless (although possible), so unencrypted +unprotected NAS messages are emitted, but wireshark will by default +refuse to dissect plain messages because according to the spec most +messages need to be at least integrity protected. + +Ubuntus ModemManager will interfere with the modem, so it needs to be +told to leave the modem alone. This can be accomplished by adding the +following line to +/etc/udev/rules.d/69-block-mm.rules : +ATTRS{idVendor}=="2c7c" ATTRS{idProduct}=="0125", ENV{ID_MM_DEVICE_IGNORE}="1 + +This example is for quectel ec25-e, adjust the USB VID:PID according to +what lsusb tells you about your particular modem. The rules then need to +be reloaded and ModemManager restarted: +sudo udevadm control --reload-rules +sudo udevadm trigger +sudo systemctl restart ModemManager + +There appears to be a bug on Ubuntu 18.04 and the ModemManager will still +interfere, see +https://bugs.launchpad.net/ubuntu/+source/modemmanager/+bug/1827328 + + |