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DES encryption Key from a passphrase

bv flag

I have been given a DES encryption assignment. I was given the Cipher text, the Plain text and the "passphrase". The passphrase consist of a 4 byte hex string. I have studied several different tutorials on you-tube about the workings of DES but I still can't seem to be able to figure out the key. I have tried to add nulls between each character to create a 64 bit key and I have reversed the characters to create the same 64 bit key. Is there anyone here that can tell me of different ways to turn the 4 byte passphrase into a 64 bit key??? Maybe there are different ways to perform DES that I have not seen yet.

kodlu avatar
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The LSB bit of each DES key byte is a parity check which ensures odd parity. See the link. Do your bytes obey this? [1]: https://crypto.stackexchange.com/questions/66904/parity-checking-on-des-key-if-using-ascii-chars
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