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Mini Shell
Mini Shell
/* 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) */
Zerion Mini Shell 1.0