Random musings
One of the most important properties of a cryptographic hash function is that of “Strong collision-resistance“, that is, it should be "computationally infeasible" to find distinct inputs x1, x2 such that hash(x1) = hash(x2). For the SHA-1 hash function, which generates a 160 bit hash, to have strong collision resistance, only a brute force attack … Read more
Snow3G is one of the two algorithms (the other being AES) algorithms used in LTE (4G) mobile network. The specifications for LTE come from the standards body called 3GPP and include the specification and reference implementation in C for the Snow 3G algorithm. There is an algorithm for confidentiality (encryption/decryption), and an algorithm for integrity. … Read more
Elliptic Curve Cryptography: computing shared key If Alice and Bob want to exchange encrypted messages, they need to first agree on a Key. This shared key (also known as symmetric key) will be used to by both parties to encrypt messages. There are many ways of arriving at the shared key (including the old fashioned … Read more
There is no substitute for detailed code reviews, more so if the code is related to security. Any changes to such code, however minor, should be reviewed. However, in addition, it also helps if the compiler, tools etc can help in flagging potential errors. Take the case of the very serious security error in ios/mac … Read more
Note 1: This article is executable code. You can copy and paste this article in a file with extension .lhs (say crypto.lhs), load it in a haskell interpreter and run the examples! You can get started by installing the haskell platform on Windows, Linux or Mac. You can learn Haskell by reading the excellent tutorial … Read more