.NET library for FNV, MurmurHash3 and SipHash algorithms
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README.md

HashDepot

NuGet Version Build Status

I have been implementing various hash functions that are absent in .NET framework. I decided to converge them into a library. My primary goals are to provide well-tested and performant implementations. The library currently supports SipHash, MurmurHash3, FNV-1 and FNV-1a.

To install it on NuGet:

Install-Package HashDepot

SipHash

SipHash is resistant to hash-flood attacks against hashtables and uses a key parameter to ensure HMAC-like authenticity yet faster. Unfortuantely a native .NET implementation does not exist. It is my take on it, and it is really fast for a managed environment. It's standard SipHash-2-4 implementation with 64-bit. To use it:

using HashDepot;
var buffer = Encoding.ASCII.GetBytes("some string");
var key = new byte[16] { .. your random key here .. };
ulong result = SipHash.Hash64(buffer, key);

Note: The largest buffer size supported for hashing is 2GB. Streaming hashing is not supported.

MurmurHash3

MurmurHash3 provides a good balance between performance and homogenity but is essentially prone to hash-flood attacks (trivial to force collisions). An example use is:

using HashDepot;
var buffer = Encoding.ASCII.GetBytes("some string");
uint seed = .. preferred seed value ...
uint result = MurmurHash3.Hash32(buffer, seed);

FNV

A straightforward implementation of FNV-1 and FNV-1a hash algorithm for .NET. Usage is very simple. For instance to calculate 32-bit FNV-1a hash of ASCII string "some string":

using HashDepot;
var buffer = Encoding.ASCII.GetBytes("some string");
uint result = Fnv1a.Hash32(buffer); // 32-bit hash
ulong result = Fnv1a.Hash64(buffer); // 64-bit hash

I started out creating a full blown HashAlgorithm implementation first but it seemed more suitable for cryptographic hash algorithms. FNV-series are more oriented towards hashing simple data, like ASCII strings. So I kept them as static functions.

Benchmarks

CPU: Intel Core i7-7700K Kaby Lake @ 3.60Ghz 1000 iterations over 1048576 bytes of buffer

Name Ops/sec
Checksum (32-bit) 2754.57
Fnv1a (32-bit) 906.26
Fnv1a (64-bit) 945.38
MurmurHash3 (32-bit) 3421.65
SipHash (64-bit) 2226.59

License

MIT License. See LICENSE file for details