Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [blowfish]

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 its origin, it has been analyzed considerably. Blowfish is unpatented, license-free, and available free for all uses.

Blowfish is an encryption algorithm that can be used as a replacement for the DES or IDEA algorithms. It is a symmetric (that is, a secret or private key) block cipher that uses a variable-length key, from 32 bits to 448 bits, making it useful for both domestic and exportable use. (The U. S. government forbids the exportation of encryption software using keys larger than 40 bits except in special cases.) 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 its origin, it has been analyzed considerably. Blowfish is unpatented, license-free, and available free for all uses.

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Blowfish Weak keys

I've read about the weak key issue with Blowfish, but can't seem to find anything that explains the practical effect of weak keys on Blowfish with the full 16 rounds. Is there any actual attack upon non-reduced-round Blowfish, in the event that a…
Blowfish
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Blowfish encryption with different keys produces same ciphertext

I have set up a test app with Blowfish encryption taken from someone else's library. I have been astonished to find that password "Test" gives the same encrypted text as password "TestTestTestTest". Is this normal behavior of the algorithm or is it…
Mariusz
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Blowfish, Sboxes and the digits of PI, and the P_Array

I am trying to use the Blowfish algorithm, however, I am trying to understand SBoxes that were used in the algorithm. I saw that it uses the hex digits of PI. I looked around in the web and found some codes that implements Blowfish and saw that…
User
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Decrypting a blowfish cipher with three keys

Disclaimer: I'm pretty new to cryptography and I don't have a strong mathematical background. I apologize in advance if I missed something blatantly obvious. I participated in a security CTF this weekend and I was unable to solve one of the…
GnP
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S boxes in Blowfish

I know how the s-boxes in blowfish are initialized, but how is the output sorted, I mean which bit from the input goes where in the box ? and what do mean they have 256 entries if they are 32-bit S-Boxes ?
user29481
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How to force non-negative int64_t output for blowfish encryption with int32_t input?

I would like to encrypt a series of small integers one by one. The range of them is about 0~10^8. The output must be non-negative int64_t integers. Since Blowfish is 64-bit cipher, I prefer to use it as symmetric encryption algorithm. The problems…
ShenLei
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