DSD FME

[lwvmobile]

DMRA RC4 keystream bits are applied to all 49 bits of an AMBE frame, and the left over 7 bits of the last byte of each RC4 package is discarded, so effectively, each AMBE frame needs 7 bytes, or 56 bits worth of keystream. 18 ambe frames x 7 bytes each = 126 bytes of keystream for the voice application.

 

[9a7jjg]

Thanks Iwvmobile for the explanation!
Just to note that I'm not hacking anything, I'm just testing with a known key.
Is the keystream generated for 162(9X18) or 126(7X18) bytes? In my example:
IV = bytes.fromhex('12345678')
CK = bytes.fromhex('AAAAABBBBB')
KEY = IV + CK
57aad6c42d1b79
f3452f7c8cdeab
80fb3ce939ff16
..................
or
57aad6c42d1b79f345
2f7c8cdeab80fb3ce9
39ff16b5327ecc39f9
................................
Thanks

 

[ki4hyf]

How are you implementing the KSA? When I take your IV(MI) and Key, I get:

MI/IV: 12345678
Key: AAAAABBBBB

49 bit Keystream Frames:
A8087DA0D24100
A41941041D8500
2260B4BAB82D00

56 bit Keystream Frames:
A8087DA0D24146
A41941041D855D
2260B4BAB82D70

Of course, I could be wrong.

 

[lwvmobile]

Of course, I could be wrong.

Looks alright to me.

 

[ki4hyf]

That's cool! Bookmarked.

 

[9a7jjg]

Then it is not KEY=IV+CK but KEY=CK+IV.
Are 162 or 126 bytes generated for one superframe, are all 72 bits of one frame encrypted?
Thanks

 

[ki4hyf]

Are 162 or 126 bytes generated for one superframe, are all 72 bits of one frame encrypted?

This has already been answered.

 

[radioopperator]

OK I just installed DSD-FME from github via Cygin system? I have tried all kinds of commands like this:
dsd-fme -ft -i rtl:0:770.44375M:49:+32:8:0: -C channel_map.csv -N 2> log.ans By tweaking Ive heard a few words of audio but that's all.

Can someone PLEASE configure me the correct configuration for I'm told I have to run two instances of dsd-fme at the same time to see and hear things? I use the RTL-xxxx dongles.

P.s. I can't seem to collect any log file information in the home directory?

Thanks.

 

[lwvmobile]

A little bit more information on what kind of system it is will be helpful. Is it DMR, or P25? Is it possibly a simulcast system?

Also, on your start up command, let's look at the rtl input. Is your PPM 32?

You have a channel.csv file, but aren't specifying what to do with it. If you need to trunk, you need to include the -T command. If you need to scan with it, you need to use -Y

Also, we don't need the ending colon on the rtl portion, that may be interpreted to grab the next thing it sees and try to make that a parameter and overflow the settings.

Just gonna go on a guess here, but try this command, and see what happens.

dsd-fme -ft -i rtl:0:770.44375M:0:32:12:0 -T -C channel_map.csv -N 2> log.ans

Then, if you want to see the log, going by your own code, it will be in the log.ans file.

Can someone PLEASE configure me the correct configuration for I'm told I have to run two instances of dsd-fme at the same time to see and hear things? I use the RTL-xxxx dongles.

Absolutely not true. Not sure what birdie told you that one.

 

[radioopperator]

To: Lwvmobile THANK YOU! And any others.
DMR, or P25? Is it possibly a simulcast system? (YES) to all would be the goal and conventional.

Is your PPM 32? Yes PPM in DSDPlus is 32 so I used the same.
You have a channel.csv file, but aren't specifying what to do with it. If you need to trunk, you need to include the -T command. If you need to scan with it, you need to use -Y Not knowing what to do ? I put names like channel.csv in ware I found the LOG.ANS in the home directory. But I don't know enough on what switches to turn on or off? or if I need a colon between things?

Ok, I used your line of code on a 700 simulcast ADP mostly encrypted system I heard blips of encryption (BUT) on the screen I see more data on it than ever!

I may of mist this? but has anyone been nice enough to post some ware we can find working code like this
dsd-fme -ft -i rtl:0:770.44375M:0:32:12:0 -T -C channel_map.csv -N 2> log.ans
and noted with each one like conventional DMR, privacy plus trunking, P25 conventional, p25 trunking something that is complete that we like change the frequency and PPM to get us up and running so we can learn how to customize it for our needs.

Thanks for all the help..

 

[RaleighGuy]

I may of mist this? but has anyone been nice enough to post some ware we can find working code like this
dsd-fme -ft -i rtl:0:770.44375M:0:32:12:0 -T -C channel_map.csv -N 2> log.ans
and noted with each one like conventional DMR, privacy plus trunking, P25 conventional, p25 trunking something that is complete that we like change the frequency and PPM to get us up and running so we can learn how to customize it for our needs.

Thanks for all the help..

A quick google search returned the Github DSD FME site with a full tutorial and explainations. Seriously, search is your friend.

dsd-fme/examples/Example_Usage.md at audio_work · lwvmobile/dsd-fme

Digital Speech Decoder - Florida Man Edition. Contribute to lwvmobile/dsd-fme development by creating an account on GitHub.

github.com

 

[lwvmobile]

Ok, I used your line of code on a 700 simulcast ADP mostly encrypted system I heard blips of encryption (BUT) on the screen I see more data on it than ever!

If its ADP, you're most likely getting the random blips of audio because trying to play the garbled audio before it gets a get decode on the encryption synchronization for P25. At that point, it would either mute the audio, or decrypt the audio if the correct key were presented to DSD-FME.

 

[radioopperator]

If its ADP, you're most likely getting the random blips of audio because trying to play the garbled audio before it gets a get decode on the encryption synchronization for P25. At that point, it would either mute the audio, or decrypt the audio if the correct key were presented to DSD-FME.

I looked in my version of DSD-FME have like 1-6 key options but I didn't see anything for ADP?
I would love to experiment with it?
Would it be possible to enter and store more than one key in the program?

Thanks for the help.

 

[lwvmobile]

ADP is RC4, so if you see mention of RC4, that'll be the one.

Yes, you can load keys in a csv file and load them in that way, see the examples folder for multi_key_hex.csv and load it with -K path/to/examples/multi_key_kex.csv , for example.

Also, just a note, but if you are doing P25, you don't need to specify the channel_map.csv file, that's just for systems that don't advertise their channel assignments. P25 for the most part always does that.

 

[radioopperator]

Ok, something not quite right unable to open `-K` error message?

dsd-fme -ft -i rtl:0:769.65625M:0:32:12:0 -T -C -k multi_key_hex.csv -N 2> log.ans

Thanks

 

[lwvmobile]

Ok, something not quite right unable to open `-K` error message?

What does the actual error message say in the log.ans file. You can open that file with NotePad++, for example, and see what it says. If there is any errors with opening files, it'll say what it is towards the very top. Most likely, probably an issue with the path to the file.

 

[ki4hyf]

dsd-fme -ft -i rtl:0:769.65625M:0:32:12:0 -T -C -k multi_key_hex.csv -N 2> log.ans

I see a couple of potential problems. You have a -C with no channel map file specified, and the "-k" should be capitalized.

 

[TheButcher]

I hope this helps someone re. file paths etc while invoking DSD-FME. Might be obvious for some, but not as much for others...


Make a batch file with this in it...

mode con: cols=119 lines=64
dsd-fme\dsd-fme.exe -fs -i tcp -U 4532 -T -C maps\maps.csv -G group\group.csv -K keys\keys.csv -P -N 2> log\log.ans


Then create these directories...

maps
groups
keys
log

Stick your x.csv files in respective directories. Log file will be created in the 'log' directory...


This batch file needs to be run from the directory just before the dsd-fme directory.

 

[radioopperator]

OK to all that have helped thank you! Not speaking enough GEEK In the last 72hrs I have learned a lot.
But I have a question on the DSD-FME PORTABLE version?
I'm trying to run something like this? -ft -i rtl:0:770.61875M:0:32:12:0 -T -K multi_key_hex.csv -N -H -Z -c capture.bin 2> log.ans
But with the % XXX % type stuff I have no idea how to insert it the correct way?

@rem Launch Tail to display the log in a seperate console window
start .\dsd-fme\tail.exe -n 40 -f %log%

@rem start dsd-fme with options and log
.\dsd-fme\dsd-fme.exe %options% 2> %log%

Is something like this correct?
.\dsd-fme\dsd-fme.exe -ft -i rtl:0:770.61875M:0:32:12:0 -T -K multi_key_hex.csv -N -H -Z -c capture.bin 2> %log%

Thanks

 

[lwvmobile]

Oh, if you are looking at the start-dsd-fme.bat file that is placed in the portable folder, the idea is to just edit the option line with all the options you want, and leave the rest of it alone, and what it will do is run with those options. All the other stuff in the log is just to create a log file with the current datetime in the log fodler and it'll open that log and follow it. So basically, just move all the stuff you wrote into the startup there and put it into options, or you can run it the way you have it there, either way should be fine.