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dorcky

Contributor

Registered: 2020-04-04

Posts: 2

Mifare classic 1k algo

Hello everyone!

I play around with a mifare classic 1k card and I try to get out the algo behind one sector of the card. The line is the last one of sector 1, because the 1st and 2nd, it is always the same and never change.

Here are the first 2 lines:

00 00 78 03 00 00 00 00 00 00 1B 1C 01 00 00 40
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0B

And here are some samples of the last line...

49 B4 7B 38 00 00 00 00 00 00 00 00 95 03 00 6E 
4F B4 7E 38 00 00 00 00 00 00 00 00 96 03 00 41 
B1 B4 7E 38 00 00 00 00 00 00 00 00 97 03 00 9F 
A4 A9 83 28 00 00 00 00 00 00 00 00 98 03 00 E6 
D2 A9 83 28 00 00 00 00 00 00 00 00 99 03 00 31 
2F 50 86 28 00 00 00 00 00 00 00 00 9B 03 00 AB 
11 15 7F 38 00 00 00 00 00 00 00 00 A0 03 00 30 
28 15 7F 38 00 00 00 00 00 00 00 00 A1 03 00 E5 
6B 2F 87 28 00 00 00 00 00 00 00 00 A3 03 00 06 
8D 96 7F 38 00 00 00 00 00 00 00 00 A4 03 00 49 
DC 9A 82 38 00 00 00 00 00 00 00 00 AC 03 00 58 
EE 9A 82 38 00 00 00 00 00 00 00 00 AD 03 00 05 
FC 9A 82 38 00 00 00 00 00 00 00 00 AE 03 00 68 
0D 9B 82 38 00 00 00 00 00 00 00 00 AF 03 00 53 
1D 9B 82 38 00 00 00 00 00 00 00 00 B0 03 00 5A 
4C 39 89 28 00 00 00 00 00 00 00 00 B1 03 00 10 
5B 39 89 28 00 00 00 00 00 00 00 00 B2 03 00 AA 
6C 39 89 28 00 00 00 00 00 00 00 00 B3 03 00 20 
7B 39 89 28 00 00 00 00 00 00 00 00 B4 03 00 9C 
8C 39 89 28 00 00 00 00 00 00 00 00 B5 03 00 BC 
9B 39 89 28 00 00 00 00 00 00 00 00 B6 03 00 06 
21 A6 82 38 00 00 00 00 00 00 00 00 B7 03 00 8B

P.S. the line was dumped from card, after was used in diffrent locations:

I found that exist an increment byte on "0C" location, witch is incremented each time when the card is used. (sorry for skipping some readings)
I think the first 8 bytes are timestamp (not 100% sure) but is definately incremented after each use.
Maybe the last byte is a checksum of the last line ? Or the last 3 line (hole sector)?  Not sure yet.
If anyone has a clue..

Thank`s for now!

iceman

Administrator

Registered: 2013-04-25

Posts: 9,537

Website

Re: Mifare classic 1k algo

You would need to show us complete dumps,  as is this is way too little information to go with.
You would also need to tell which system,  what its purpose,  company name,  in order to find information / datasheets about it.