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.

                                          April 25, 2017                           highwayhash(3)