SHA-2 is a family of cryptographic hash functions designed by the NSA and published by NIST in 2001. The family includes various output lengths (224, 256, 384, and 512 bits). The SHA-2 family will eventually be replaced by the winner of NIST's hash function competition.
It's been said that CRC-64 is bijective for a 64-bit block. It the corresponding statement true for SHA-2?
I've come up with this little routine for doing encryption using the SHA-2 (in this case SHA-256) hash function. As such it is a block cipher with a 256 bit (32 byte) block size and an arbitrary key ...
In terms of security strength, Is there any difference in using the SHA-256 algorithm vs using any random 256 bits of the output of the SHA-512 algorithm? Similarly, what is the security difference ...
I'm reading the book Network Security Essentials written by William Stallings. To create a message digest with SHA-512, we have to go through some steps: append padding bits. append length ...
There is already a question asking "Why initialize SHA1 with specific buffer?" and my question follows on from this: Why are the initial states of hash functions often non-zero? For most, I have ...
Are there any known collisions for the hash functions SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512? By that, I mean are there known values of $a$ and $b$ where $F(a) = F(b)$ and $a ≠ b$?
Generate a 256-bit random nonce. XOR it with a 256-bit reusable symmetric key. This is x. We represent numbers in simple binary instead of a counting function. ...