brmlab

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====== DMR aka MotoTRBO ======
{{template>project:infobox|
name=DMR|
image=dmr.jpg|
founder=[[user:sysop]]|
interested=[[user:sysop]]\\ [[user:sysop]]|
}}

~~META:
status = idea
&relation firstimage = :project:10076716473_fb5380cf36.jpg
~~



===== Goals =====

The goals of this project:

Improve existing DMR decoding tools.

===== Resources =====

  * Documentation
    * [[https://www.etsi.org/deliver/etsi_tr/102300_102399/102398/01.04.01_60/tr_102398v010401p.pdf|ETSI TR 102 398 General system design]]
    * [[https://www.etsi.org/deliver/etsi_ts/102300_102399/10236101/02.05.01_60/ts_10236101v020501p.pdf|ETSI TS 102 361-1 Part 1: DMR air interface (AI) protocol]]
    * [[https://www.etsi.org/deliver/etsi_ts/102300_102399/10236102/02.04.01_60/ts_10236102v020401p.pdf|ETSI TS 102 361-2 Part 2: DMR voice and generic services]]
    * [[https://www.etsi.org/deliver/etsi_ts/102300_102399/10236103/01.03.01_60/ts_10236103v010301p.pdf|ETSI TS 102 361-3 Part 3: DMR data protocol]]
    * [[https://www.etsi.org/deliver/etsi_ts/102300_102399/10236104/01.10.01_60/ts_10236104v011001p.pdf|ETSI TS 102 361-4 Part 4: DMR trunking protocol]]
    * [[https://patents.google.com/patent/EP2347540B1|Patent - EP2347540B1 - Method and device for sending encryption parameters]]
    * [[https://patents.google.com/patent/RU2469485C1/en|Patent - RU2469485C1 - Method and device for transmission of coding parameters]]
    * [[https://forums.radioreference.com/threads/official-standards-documents-for-dmr-encryption.399358/|Encryption]]
  * Existing implementations
    * [[https://github.com/szechyjs/dsd|DSD]]
    * [[https://github.com/f4exb/dsdcc|DSDcc]]
    * [[https://www.dsdplus.com/|DSDPlus]]
    * [[https://github.com/IanWraith/DMRDecode|DMRDecode]]
    * [[https://github.com/DSheirer/sdrtrunk|SDRTrunk]]
    * [[https://github.com/KD8EYF/TRBO-NET|TRBO-NET]]
    * [[https://github.com/cyber5tar86/DMRlink|DMRlink]] - Motorola MotoTRBO IPSC Client
    * [[https://github.com/pd0mz/go-dmr|go-dmr]] - Golang Digital Mobile Radio protocols.
    * [[https://www.rtl-sdr.com/forum/viewtopic.php?f=3&t=5057&start=100|OpenEar]]
  * Firmware reversing projects:
    * [[https://github.com/travisgoodspeed/md380tools|md380tools]]
    * [[https://github.com/pchickey/md380-re|md380-re]]
    * [[https://www.youtube.com/watch?v=cE4f6JaBfSI]]
    * [[https://github.com/rogerclarkmelbourne/OpenGD77|OpenGD77]]
    * [[https://kk4vcz.com/posts/th-d74-firmware/|Reverse Engineering Kenwood TH-D74 Firmware]]

===== Encryption =====
Basic: Using Basic "encryption" is more of a vendor lock. It offers absolutely no security whatsoever and can be monitored in real-time with software. Guessing the key is trivial. The advantage of Basic privacy is that it does not degrade audio quality, however it is proprietary to Motorola. Any implementation of Basic Privacy means Motorola-only.

Enhanced: This is ARC4 40-bit encryption. RC4 is defined as part of the DMR standard. There are 1,099,511,627,775‬ possible keys. Keys are entered as a 5-byte (10 character) hex (0-F) number. This may seem secure, but it's far from it. This number is trivial and a modern computer can blast through the key-space in near real-time.

You should also know the DMR standard was not designed with encryption/privacy in mind. Encryption was an afterthought. To address this, Motorola devised a method to incorporate the Key ID, algorithm ID and IV into a transmission, by substituting some bits of the voice payload. Motorola filed the patent for this in Oct. 2009. What's this mean? It means when encryption is used on DMR, the audio quality is sacrificed to some extent.

Symmetric: Symmetric refers to Symmetric keys, as in the AES-256 ("AES") standard (FIPS 197). AES-256 is also part of the DMR standard.

* [[https://web.archive.org/web/20150317142628/https://communications.support/threads/7014-MOTOTRBO-AES256-Facts|MOTOTRBO AES256 Facts]]