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#1 2019-11-07 12:04:35

yukihama
Contributor
Registered: 2018-05-13
Posts: 133

[solved]first 4bytes of valid Mifare classic Block0 data ???

Hi
solved
for example:
printed card number is AH2378BC
then the valid block 0 data starting from BC7823AH

Last edited by yukihama (2019-11-09 09:09:38)

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#2 2019-11-07 17:02:20

iceman
Administrator
Registered: 2013-04-25
Posts: 9,497
Website

Re: [solved]first 4bytes of valid Mifare classic Block0 data ???

It would be easier if you had a larger sampleset to play with.

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#3 2019-11-08 03:38:37

yukihama
Contributor
Registered: 2018-05-13
Posts: 133

Re: [solved]first 4bytes of valid Mifare classic Block0 data ???

iceman wrote:

It would be easier if you had a larger sampleset to play with.

Hi Dear Mr iceman
have you played with it before?I have some data and thought they are some kind of CRC bits but tried many CRC alogorithm and failed....

Can you give me some hints about the algorithm of printed card number and valid block 0 data?  I am grateful...

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#4 2019-11-08 11:59:47

Onisan
Contributor
From: London
Registered: 2016-07-18
Posts: 88

Re: [solved]first 4bytes of valid Mifare classic Block0 data ???

Looks pretty straight forward.
Printed Card Number                                 AH 23 78 BC      (4 Byte ID)
Matches first 4 Bytes of MIFARE Card ID:    BC 78 23 AH  (in Reverse.)

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#5 2019-11-08 14:44:39

yukihama
Contributor
Registered: 2018-05-13
Posts: 133

Re: [solved]first 4bytes of valid Mifare classic Block0 data ???

[solved]valid Mifare classic Block0 data ???

Last edited by yukihama (2019-11-09 08:37:39)

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#6 2019-11-08 15:11:44

iceman
Administrator
Registered: 2013-04-25
Posts: 9,497
Website

Re: [solved]first 4bytes of valid Mifare classic Block0 data ???

try xoring all bytes together and see what you get

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#7 2019-11-09 08:36:33

yukihama
Contributor
Registered: 2018-05-13
Posts: 133

Re: [solved]first 4bytes of valid Mifare classic Block0 data ???

iceman wrote:

try xoring all bytes together and see what you get

Genuis please allow me to kiss your ass ,LOL

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#8 2019-11-09 09:30:14

piwi
Contributor
Registered: 2013-06-04
Posts: 704

Re: [solved]first 4bytes of valid Mifare classic Block0 data ???

This post would be more useful to others if you had not deleted the 5th byte and would correct the 'AH' byte.

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