Hash Lab

Catalog

Algorithms

One page per hash function: definition, where it is used, internal structure, security status, known attacks, and references.

Cyclic redundancy checks

Polynomial division over GF(2). Detect random transmission errors; trivially defeatable by an adversary.

Checksums

Lightweight integrity verifiers. Faster than CRCs, weaker per output bit.

Non-cryptographic hash functions

Fast, well-distributed hashes for hash tables, Bloom filters, dedup, sketches. No security goal against an adversary.

Keyed cryptographic hash functions (MACs)

Message authentication codes. Produce a tag that can only be created or verified with the right key.

Unkeyed cryptographic hash functions

Collision-resistant hashes for signatures, content addressing, integrity. The bulk of the field.

Password hashing & KDFs

Deliberately slow / memory-hard hashes for storing passwords and deriving keys. Different security goal from collision resistance.