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Edit File: perl_siphash.h
/* This is SipHash by Jean-Philippe Aumasson and Daniel J. Bernstein. * The authors claim it is relatively secure compared to the alternatives * and that performance wise it is a suitable hash for languages like Perl. * See: * * https://www.131002.net/siphash/ * * This implementation seems to perform slightly slower than one-at-a-time for * short keys, but degrades slower for longer keys. Murmur Hash outperforms it * regardless of keys size. * * It is 64 bit only. */ #ifdef CAN64BITHASH #define SIPROUND \ STMT_START { \ v0 += v1; v1=ROTL64(v1,13); v1 ^= v0; v0=ROTL64(v0,32); \ v2 += v3; v3=ROTL64(v3,16); v3 ^= v2; \ v0 += v3; v3=ROTL64(v3,21); v3 ^= v0; \ v2 += v1; v1=ROTL64(v1,17); v1 ^= v2; v2=ROTL64(v2,32); \ } STMT_END #define SIPHASH_SEED_STATE(key,v0,v1,v2,v3) \ do { \ v0 = v2 = U8TO64_LE(key + 0); \ v1 = v3 = U8TO64_LE(key + 8); \ /* "somepseudorandomlygeneratedbytes" */ \ v0 ^= UINT64_C(0x736f6d6570736575); \ v1 ^= UINT64_C(0x646f72616e646f6d); \ v2 ^= UINT64_C(0x6c7967656e657261); \ v3 ^= UINT64_C(0x7465646279746573); \ } while (0) PERL_STATIC_INLINE void S_perl_siphash_seed_state(const unsigned char * const seed_buf, unsigned char * state_buf) { U64 *v= (U64*) state_buf; SIPHASH_SEED_STATE(seed_buf, v[0],v[1],v[2],v[3]); } #define PERL_SIPHASH_FNC(FNC,SIP_ROUNDS,SIP_FINAL_ROUNDS) \ PERL_STATIC_INLINE U64 \ FNC ## _with_state_64 \ (const unsigned char * const state, const unsigned char *in, const STRLEN inlen) \ { \ const int left = inlen & 7; \ const U8 *end = in + inlen - left; \ \ U64 b = ( ( U64 )(inlen) ) << 56; \ U64 m; \ U64 v0 = U8TO64_LE(state); \ U64 v1 = U8TO64_LE(state+8); \ U64 v2 = U8TO64_LE(state+16); \ U64 v3 = U8TO64_LE(state+24); \ \ for ( ; in != end; in += 8 ) \ { \ m = U8TO64_LE( in ); \ v3 ^= m; \ \ SIP_ROUNDS; \ \ v0 ^= m; \ } \ \ switch( left ) \ { \ case 7: b |= ( ( U64 )in[ 6] ) << 48; /*FALLTHROUGH*/ \ case 6: b |= ( ( U64 )in[ 5] ) << 40; /*FALLTHROUGH*/ \ case 5: b |= ( ( U64 )in[ 4] ) << 32; /*FALLTHROUGH*/ \ case 4: b |= ( ( U64 )in[ 3] ) << 24; /*FALLTHROUGH*/ \ case 3: b |= ( ( U64 )in[ 2] ) << 16; /*FALLTHROUGH*/ \ case 2: b |= ( ( U64 )in[ 1] ) << 8; /*FALLTHROUGH*/ \ case 1: b |= ( ( U64 )in[ 0] ); break; \ case 0: break; \ } \ \ v3 ^= b; \ \ SIP_ROUNDS; \ \ v0 ^= b; \ \ v2 ^= 0xff; \ \ SIP_FINAL_ROUNDS \ \ b = v0 ^ v1 ^ v2 ^ v3; \ return b; \ } \ \ PERL_STATIC_INLINE U32 \ FNC ## _with_state \ (const unsigned char * const state, const unsigned char *in, const STRLEN inlen) \ { \ union { \ U64 h64; \ U32 h32[2]; \ } h; \ h.h64= FNC ## _with_state_64(state,in,inlen); \ return h.h32[0] ^ h.h32[1]; \ } \ \ \ PERL_STATIC_INLINE U32 \ FNC (const unsigned char * const seed, const unsigned char *in, const STRLEN inlen) \ { \ U64 state[4]; \ SIPHASH_SEED_STATE(seed,state[0],state[1],state[2],state[3]); \ return FNC ## _with_state((U8*)state,in,inlen); \ } PERL_SIPHASH_FNC( S_perl_hash_siphash_1_3 ,SIPROUND; ,SIPROUND;SIPROUND;SIPROUND; ) PERL_SIPHASH_FNC( S_perl_hash_siphash_2_4 ,SIPROUND;SIPROUND; ,SIPROUND;SIPROUND;SIPROUND;SIPROUND; ) #endif /* defined(CAN64BITHASH) */