decoding SMS and Kc

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josefh...@hushmail.com

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Mar 10, 2022, 11:05:23 AM3/10/22
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Hello list

since it seems that my mobile dosent support AT commands, I am trying to pull the KC
with tools like Simspy, but this tools says: "the key is not available"
(one SIM is really old, one SIM card is in use in a mobile using the GSM band and one SIM
is a 3G mobile)


Are there really SIM cards without KC's or am I doing something wrong?


Thanks!

Joe

Nikos Balkanas

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Mar 10, 2022, 11:41:00 AM3/10/22
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Hi Joe,

All sims have their keys. Otherwise they wouldn't be able to talk to the
BTS. A mobile without speech is trash...;-)

BR
Nikos
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josefh...@hushmail.com

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Mar 11, 2022, 10:38:36 AM3/11/22
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Thank's a lot Nikos for the feedbackj! May I ask you how you pull the kc from a SIM?

Joe

Nikos Balkanas

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Mar 11, 2022, 4:35:44 PM3/11/22
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Sorry, can't help with that.
I use kraken for gsm keys:(
However, you can find a lot of information about it in the web:)

BR
Nikos

josefh...@hushmail.com

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Apr 19, 2022, 11:02:06 AM4/19/22
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Thank's fot that info. I heard, that for that purpose, Kraken or Osmocom could be used too.
What approach/environment is easier to setup and handle?

Joe


On 10.3.2022 at 5:40 PM, "Nikos Balkanas" <nbal...@gmail.com> wrote:
>

Nikos Balkanas

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Apr 19, 2022, 12:11:00 PM4/19/22
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Osmocom, doesn't crack keys.
So, the only option is Kraken...

HTH
Nikos

josefh...@hushmail.com

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Apr 20, 2022, 10:46:36 AM4/20/22
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Thanks.
->Osmocom, doesn't crack keys.
Ok thats right! But according the following info's cracking is not even required, because there is an other approach. Pls see:


https://security.stackexchange.com/questions/95738/how-do-i-get-kc-from-my-sim-card

->OsmocomBB Mobile App
->Download and install the app
->Upload layer1 to your phone
->Run mobile -i 127.0.0.1
->telnet 127.0.0.1 4247
->After that simply say: show subscriber 1 At the top you should see the Kc printed.

Nikos Balkanas

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Apr 20, 2022, 11:57:47 AM4/20/22
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Ok. That's how you get your key from your own SIMM:)
I thought you were asking about other ppl keys...

Nikos

josefh...@hushmail.com

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Apr 22, 2022, 10:33:52 AM4/22/22
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Thank's Nikos!

->Ok. That's how you get your key from your own SIMM:)
That is my intention, just wanna decode the "undeliverable DLR" (the answer to my Ping SMS is sent before:)

Do I not the KC for that scenario?


Regards,

Joe

Nikos Balkanas

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Apr 22, 2022, 11:27:30 AM4/22/22
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Your phone has your key. It will decode the DLR for you.
No need to do anything yourself:)

Nikos

Nikos Balkanas

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Apr 23, 2022, 9:40:48 AM4/23/22
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Hi Joe,

Actually It's a little more involved than that:(
Try it, but I am not sure that your phone will display all you need.
You need a key to read the DLR in a 3rd party, like grgsm...
But you can't use your key to read his DLR. You need his key.
Unfortunately you need kraken for that:(

HTH
Nikos

josefh...@hushmail.com

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Apr 26, 2022, 11:25:16 AM4/26/22
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Hello Nikos

Thank you very much Nikos! This info does really help me! It's totally ok for me to learn Kraken, even I don't know
yet were to store the tables :)

At the moment there is still a question:

Do you know, if a "normal" ping-sms sent with a sendsms app like HushSMS, will trigger an undeliverable DLR
(sent back from the provider) or do i need to craft myself a blanc/corrupted SMS for that?


Regards,

Joe



On 23.4.2022 at 3:40 PM, "Nikos Balkanas" <nbal...@gmail.com> wrote:
>
>Hi Joe,
>
>gsm+uns...@googlegroups.com.

Nikos Balkanas

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Apr 26, 2022, 12:03:29 PM4/26/22
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Sorry, I don't know ping-sms or HushSMS:(
If in doubt, send a ping-sms to yourself, to see what you get.
If you get a notification in your phone, that's no good:(

josefh...@hushmail.com

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May 3, 2022, 10:21:20 AM5/3/22
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Ok I am going to learn Kraken. Will I have to learn how to de-hopping traffic for this scenario as well?

Thank's!

Joe


On 23.4.2022 at 3:40 PM, "Nikos Balkanas" <nbal...@gmail.com> wrote:
>
>Hi Joe,
>
>gsm+uns...@googlegroups.com.

Nikos Balkanas

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May 3, 2022, 12:09:52 PM5/3/22
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No, No hopping needed to get the DLR:)
I don't think you get hopping with SMS. They are very short:)

Nikos Balkanas

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May 3, 2022, 12:17:11 PM5/3/22
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Before you get in too deep with Kraken,
check with your (sender) phone if it displays what you need from the DLR...

Nikos Balkanas

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May 5, 2022, 7:41:22 AM5/5/22
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If not, get yourself an android phone, which is open source, and
modify it to display
the DLR fields that you are interested and even save the decrypted
packets to a log:)

Nikos

josefh...@hushmail.com

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May 5, 2022, 10:36:48 AM5/5/22
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I am on LineageOS:) Interesting...is your approach not accessing "the internal SMS storage"? And what means modify?

Thank's!

Joe

Nikos Balkanas

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May 5, 2022, 11:23:04 AM5/5/22
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LineageOS is open source android. Find what handles DLRS and change it
to meet your needs.

HTH
Nikos

josefh...@hushmail.com

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May 9, 2022, 10:39:52 AM5/9/22
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Hello and thank's again

it was easy to find out how to turn on "Delivery report" in LineageOS, But till now, I was unable to determine the TP-originating address :(

Are those infos needed afterwards in grgsm_decode?


Thank's and regards,

Joe

Nikos Balkanas

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May 9, 2022, 10:45:15 AM5/9/22
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DLR is optional. You need to request it to get it:)
You don't need anything else to see the DLR in grgsm, except for the
key from kraken.
On the other hand, if you want to see the DLR in your mobile, you
don;t need a key, your phone has the key.
but you have to find out a way to display the whole DLR packet in your phone:)

HTH
Nikos

josefh...@hushmail.com

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May 11, 2022, 10:21:49 AM5/11/22
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Hello

->DLR is optional. You need to request it to get it:)
I turned on the option "Delivery Report" in the Message App. Ok?

->but you have to find out a way to display the whole DLR packet in your phone
Can this info be found in the "hidden" "Phone Info", where infos like IMEI, Neighbor Cell Infos
are shown ?

2.
Is this info(DLR) not anymore available if the phone is rebooted, that means it is not stored on the
filesystem of the mobile?


Thanks and regards,

Joe

Nikos Balkanas

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May 11, 2022, 10:44:39 AM5/11/22
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See answers inlined.

BR
Nikos

On Wed, May 11, 2022 at 5:21 PM <josefh...@hushmail.com> wrote:
>
> Hello
>
> ->DLR is optional. You need to request it to get it:)
> I turned on the option "Delivery Report" in the Message App. Ok?

That's it:)
> ->but you have to find out a way to display the whole DLR packet in your phone
> Can this info be found in the "hidden" "Phone Info", where infos like IMEI, Neighbor Cell Infos
> are shown ?
> 2.
> Is this info(DLR) not anymore available if the phone is rebooted, that means it is not stored on the
> filesystem of the mobile?

I don't know android. You should talk to android users:)
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