Blowfish is an encryption algorithm that can be used as a replacement for the DES or IDEA algorithms. Blowfish was designed in 1993 by Bruce Schneier as an alternative to existing encryption algorithms. Designed with 32-bit instruction processors in mind, it is significantly faster than DES. Since ...
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Can one efficiently iterate valid bcrypt hash output values?
bcrypt is an intentionally slow hash algorithm. In my last protocol idea, I wanted to use it to expand a password and then only transfer the bcrypt-hashed password.
An efficient attack on this would ...
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Why exactly is Blowfish faster than AES?
I've not been able to understand exactly the reason behind Blowfish being faster than AES. Is it dependent on the block size? Or is it processor dependent? (if Yes, then lets assume that AES ...
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Is Blowfish strong enough for VPN encryption?
I'm looking at an OpenVPN connection between two sites configured to use 128 bit Blowfish in CBC mode, and trying to figure out how to assess the strength, but I just don't know enough of the maths.
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Understanding a Blowfish cryptanalysis
I'm reading a cryptanalysis on Blowfish, and I've come across something that I don't quite get. Let's denote
$$\delta = a \oplus a'$$
where a and a' are bytes that cause a collision in some S-box ...
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AES vs Blowfish taking key-length into account
I understand that Blowfish is getting old, but is still a secure algorithm, and that AES is very popular, and is recommended by most people. My question is, how do the two compare when a 256-bit key ...
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Blowfish Encryptions in Bcrypt hashing algorithm
I am trying to understand the ExpandKey function used in the bcrypt hashing algorithm. As per the documentation of bcrypt hashing algorithm on USENIX here:
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Hashing a password with SHA256 on the client then bcrypt on the server
I'm trying to implement a cryptographically secured storage site (not Mega, or anything similar) and am trying to prevent the user's password from ever touching the server. The password is used to ...
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Can iterated key expansion in Blowfish slow down bruteforce attacks on small key sizes?
Suppose I have to use 64-bit keys for encryption (e.g. to comply with export restrictions). For this question, assume this key is truly random, and the encryption algorithm is Blowfish.
Blowfish key ...
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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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Blowfish: hex digits of pi used for s-boxes?
Preface: here is the official site for the Blowfish algorithm:
http://www.schneier.com/blowfish.html
The Blowfish algorithm uses an s-box, which consists of hex digits of pi (found here: ...
