# All Questions

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### Known-plaintext attack on Blowfish in ECB mode

The protection scheme I faced recently seems so weak nowadays that a simple exhaustive key search would be enough to recover the user key in an acceptable amount of time (it's OK, since almost no ...
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### Given a certain entrophy per character, how long should a passphrase be to guarantee key strength?

Given an entrophy of 1.5 bits per character, how long does a passphrase have the be to guarantee a key strength of a 128 bit random key? Assuming an alphabet of 26, one character takes log2(26)=4.7 ...
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### May the problem with DES using OFB mode be generalized for all feistel ciphers

There is a problem with using DES as the block cipher in OFB mode, eg: the feedback that goes back into the next round will be encrypted with the same key $k$ resulting back into the plaintext IV used ...
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### Does the IV need to be known by AES (CBC mode)?

I was thinking about this today and thought I should ask. I think I understand IV's enough to say that they are basically the same thing as Salts when talking about hashes. They are there to improve ...
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### How do I generate decryption keys for the IDEA algorithm from the 128 bit key?

I am trying to implement IDEA algorithm in C#, just to learn how it works. I have taken a 128 bit binary key and generated the 52 encryption keys using the following code: ...
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### How secure is this perl script to use an AES encryption on files? [closed]

I am not entierly sure if it is appropriate to ask such a question here, but then again, I don't know a better place. If it is the wrong place, let me know, and I will remove it. Could someone share ...
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### PBKDF2 when dkLen and hLen have the same size

I was reading RFC 2898 and something is not clear to me. When I use PBKDF2 with SHA-256 and I want a derived key with length 32 bytes (the same length as my hash function output), your derived key ...
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### Is this hand cipher any more secure than the Vigenère cipher?

I know that inventing one's one crypto always sucks, but the problem is that hand ciphers are usually 1. very insecure 2. very slow. This is an attempt to make a relatively secure, keyable, and ...
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### AES ENCRYPTION ALGORITHM [closed]

What is the amount of decrease in the probability of decrypting a data encrypted using an AES algorithm? (That is by introducing each round out of ten whole rounds, how the probability of decryption ...
156 views

### What is the probability of breaking the AES algorithm?

I am doing a project which requires the encryption to be done using AES. Is it really possible (technically) to crack AES? If yes, please tell me: What is the probability of breaking AES? How ...