Questions tagged [rijndael]

Rijndael is a family of symmetric block-ciphers with block and keys sizes of 128, 160, 192, 224, or 256 bits.

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Implement Twofish cipher with 16-bit blocksize?

I've seen implementation of Rijndael cipher with 16-bit blocksize. And I have also tried to implement 16-bit Rijndael cipher by myself with only a little sneak peeking at the example of the ...
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How can I find or reverse engineer the whitening in an AES algorithm?

I am working with this black box cryptography scheme. I know the plain text, cipher text, and everything else except how they whiten the data (or key?). Everything is 128 bit, 16 bytes. I have two ...
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How can the Rijndael SBox be written as a linearized polynomial?

In Cryptanalysis of Block Ciphers with Overdefined Systems of Equations Nicolas Courtois and Josef Pieprzyk state (in Appendix A) that the Rijndael SBox can be written as a "linearized polynomial" $S(...
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Rijndael - is there some difference in resistance between counter in generator input and in IV?

I am thinking about Rijndael implementation in order to store tokens (cannot be hashed) - one token for one user. And finally I get stuck with key/IV generation problem :( The questions are: 1) Is ...
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Risks using .NET RijndaelManaged with static Key and IV

A company I'm consulting for has a (quite old) home grown web SSO solution based on an encrypted cookie. The auth flow looks more or less like this: User hits protected page on integrated site Site ...
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AES - Size of T-Boxes and obtaining T-Box values

In article "A high performance ST-Box based unified AES encryption/decryption architecture on FPGA" (http://www.sciencedirect.com/science/article/pii/S0141933115001945) two 32Kb dual-port BRAMs are ...
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equation of mixcolumn in the aes field

$c(y) = (03)y^3 + (01) y^2 + (01) y + (02)$ Let $d = (01)b$ in the AES field $GF(2^8)$. Provide exact equations for the bits $d_i, 0 \leq i \leq 7$, in terms of the bits $b_i$ of b. Can ...
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Rijndaelcipher mix column query

I quote a wikipedi para that says The operation consists in the modular multiplication of two four-term polynomials whose coefficients are elements of ${\displaystyle \operatorname {GF} (2^{8})} $. ...