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One common pitfall when implementing HMAC(key, data) is mishandling the case when key is longer than the underlying hash block. In your case salt is 80 octets, which is longer that SHA-256 "block" (64 octets) so the salt have to be run through SHA-256 before being XOR'ed with i_padin the HMAC. Without seeing any actual code, and provided that the test ...


4

The problem doesn't lie with curves in Weierstrass form necessarily, but with naive implementations of elliptic curve arithmetic on such curves. Basically, if you implement an ECC scheme (ECDH, ECDSA or whatever) on a smart card using a curve in Weierstrass form in the most straightforward way possible (by writing a simple double-and-add loop for ...


3

A conceivable attack is inspired by this extract of LUKS On-Disk Format Specification Version 1.1.1, section 1: A partition can have as many user passwords as there are key slots. To access a partition, the user has to supply only one of these passwords. If a password is changed, the old copy of the master key encrypted by the old password must be ...


2

T' method was introduced in the paper Cryptanalysis of Block Ciphers with Overdefined Systems of Equations by Nicolas Courtois and Josef Pieprzyk (see section 6.1 and Appendix E). It is a part of XSL attack on block ciphers (such as Rijndael and Serpent). During XSL attack cipher is represented as a system of multivariate quadratic polynomials and the goal ...


1

This hastily written implementation of HKDF in C# agrees with the RFC test vectors: private const int SHA1 = 1; private const int SHA256 = 2; private static HMAC NewHMAC(int h, byte[] key) { switch (h) { case SHA1: return new HMACSHA1(key); case SHA256: return new ...



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