HighwayHashSwift

This package is a Swift package manager wrapper for HighwayHash — a fast, stable, and dos-attack resistent hashing algorithm.

• HighwayHash is faster than SipHash (which backs Swift's Hashable implementation.)
• HighwayHash is stable for a given seed value. Unlike Swift's Hashable you can serialize HighwayHash output to match values across sessions.
• This package bundles the c++ implementation of HighwayHash and provides a simplified API to swift.
  • (No incremental hashing API is currently exposed. Open to code contributions.)
• This package is usable on arm64 and x86_64 variants of macOS, iOS, and linux.
• The bundled code, and this package, are Apache 2 licensed.
• The underlying library contains an implementation of SipHash. It is also re-exposed here.

Usage

HighwayHash (and SipHash) accept Data or String input and return a UInt64 hash.

    import HighwayHash

    // Choose a seed
    let seed = Seed(a: 1, b: 0, c: 6, d: 6)

    // Instantiate your hasher
    let hasher = HighwayHash(seed: seed)
    
    // Hash your data
    let output = hasher.hash(data: input)

    // Given a stable seed, observe a stable output value
    XCTAssertEqual(output, UInt64(10_502_827_635_072_092_050))

    // Note: the hasher instance is consumed and can't be reused.
    // Reinstantiate with the same seed if desired.