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Crypto Algorithm Question - Xor Encryption


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  #1  
Old January 3rd, 2013, 09:40 AM
contrast61 contrast61 is offline
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Crypto Algorithm Question - Xor Encryption
Hi all ....i have a xor encryption file and the sender told me that :
When you read it out it is crypted, with xor coding, 8 unfined hex value d2, subract 8bit unfined 4C then the file
is a ordinary bin file.
I dont understand what can i do to decrypt the file.
pls someone help me
Thanks in Advance
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Old January 3rd, 2013, 10:12 AM
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salem salem is offline
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Well if by "unfined" you mean "unsigned", then perhaps

Code:
unsigned char c = a byte from your file
c ^= 0xd2;
c -= 0x4c;
// write c to your new file
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Old January 3rd, 2013, 12:11 PM
contrat61 contrat61 is offline
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Salem thanks for your fast reply ...so i will must open the file with winhex or hexplorer or Notepad++ and what can i do to decrypt the file? Or if you have a better sugestion pls tell me it is very important for me.
Thanks again
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Old January 3rd, 2013, 01:38 PM
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You're right Salem for your message on another forum but I'm trying to find a way that I can read the file ... I know it's very annoying guys like me to ask questions that may seem stupid to someone who knows.
Thank you so much giving me immediately replied with the code should be put'll try to find a way to finish
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Old January 4th, 2013, 07:51 AM
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I did finally with your help ... Thank Salem
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