highwayhash(3)

NAME
highwayhash - fast strong 64-bit hash functions

SYNOPSIS
#include <highwayhash/c_bindings.h> /* C */
    uint64_t SipHashC(const uint64_t* key, const char* bytes, const uint64_t size);
    uint64_t SipHash13C(const uint64_t* key, const char* bytes, const uint64_t size);
    uint64_t HighwayHash64(const HHKey key, const char* bytes, const uint64_t size); #include <highwayhash/highwayhash.h> /* C++ */
    using namespace highwayhash;
    void HighwayHashT(State* HH_RESTRICT state,
                      const char* HH_RESTRICT bytes, const size_t size,
                      Result* HH_RESTRICT hash); #include <highwayhash/sip_hash.h> /* C++ */
    using namespace highwayhash;
    HH_U64 SipHash(const SipHashState::Key& key, const char* bytes,const HH_U64 size); Link with -lhighwayhash

DESCRIPTION
Hash functions are widely used, so it is desirable to increase their speed and security. This package provides two 'strong' (well-distributed and unpredictable) hash functions: a faster version of SipHash, and an even faster algorithm we call HighwayHash. SipHash is a fast but 'cryptographically strong' pseudo-random function by Aumasson and Bernstein [https://www.131002.net/siphash/siphash.pdf]. HighwayHash is a new way of mixing inputs which may inspire new cryptographically strong hashes. Large inputs are processed at a rate of 0.24 cycles per byte, and latency remains low even for small inputs. HighwayHash is faster than SipHash for all input sizes, with 5 times higher throughput at 1 KiB. We discuss design choices and provide statistical analysis and preliminary cryptanalysis in https://arxiv.org/abs/1612.06257. Note, SipHash wants an uint64_t[2] key while HighwayHash uint64_t[4] .

EXAMPLES
64-bit SipHash for any CPU:
    #include "highwayhash/sip_hash.h"
    using namespace highwayhash;
    const HH_U64 key2[2] HH_ALIGNAS(16) = {1234, 5678};
    char in[8] = {1};
    return SipHash(key2, in, 8); 64, 128 or 256 bit HighwayHash for the CPU determined by compiler flags:
    #include "highwayhash/highwayhash.h"
    using namespace highwayhash;
    const HHKey key HH_ALIGNAS(32) = {1, 2, 3, 4};
    char in[8] = {1};
    HHResult64 result; // or HHResult128 or HHResult256
    HHStateT<HH_TARGET> state(key);
    HighwayHashT(&state, in, 8, &result); 64, 128 or 256 bit HighwayHash for the CPU on which we're currently running:
    #include "highwayhash/highwayhash_target.h"
    #include "highwayhash/instruction_sets.h"
    using namespace highwayhash;
    const HHKey key HH_ALIGNAS(32) = {1, 2, 3, 4};
    char in[8] = {1};
    HHResult64 result; // or HHResult128 or HHResult256
    InstructionSets::Run<HighwayHash>(key, in, 8, &result); C-callable 64-bit HighwayHash for the CPU on which we're currently running:
    #include "highwayhash/c_bindings.h"
    const uint64_t key[4] = {1, 2, 3, 4};
    char in[8] = {1};
    return HighwayHash64(key, in, 8);

SEE ALSO
/usr/include/highwayhash/c_bindings.h (C) /usr/include/highwayhash/highwayhash.h (C++)

BUGS
https://github.com/google/highwayhash/issues

AUTHOR
Upstream authors are Jan Wassenberg <jan.wassenberg@gmail.com> and Jyrki Alakuijala <jyrki.alakuijala@gmail.com>, updated 2017-02-07 This manpage was created by Adam Borowski <kilobyte@angband.pl>, and completed by Zhou Mo <cdluminate@gmail.com> according to upstream readme and header files.