OsmocomDECT

h1. Dectmon

@dectmon@ is a DECT protocol decoder. It can decode DECT MAC, DLC and NWK layer messages and display them in a human readable format.

== Build instructions ==

<pre>

# sh autogen.sh

# sh configure

# make

</pre>

== Usage ==

Configure the cluster in PP monitor mode:

<pre>

# dect-cluster-add --name cluster0 --emc 0x12f5 --fpn 0x0be9f --mode PP

# dect-cell-add --name cell0 --cluster cluster0 --flags monitor

# dect-transceiver-bind --transceiver trx0 --cell cell0

</pre>

Then start the @dectmon@ application. By default only NWK layer messages are displayed, use @--dump-mac/-m=yes@ to dump MAC layer messages and

@--dump-dlc/-d=yes@ to dump DLC layer messages. To specify the PIN to use for calculating user authentication keys, use @--auth-pin/-p=PIN@.

h2. Deciphering

If dectmon is able to track the initial pairing of a phone, it calculates the resulting user authentication key, which is used to derive cipher keys

during authentication. dectmon calculates the cipher key and uses it to decipher encrypted connections. The user authentication key is permanently

stored in @$HOME/dectmon.keys@ and read from that file when a phone is first seen after a restart.