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Edit File: hv_func.h
/* hash a key *-------------------------------------------------------------------------------------- * The "hash seed" feature was added in Perl 5.8.1 to perturb the results * to avoid "algorithmic complexity attacks". * * If USE_HASH_SEED is defined, hash randomisation is done by default * (see also perl.c:perl_parse() and S_init_tls_and_interp() and util.c:get_hash_seed()) */ #ifndef PERL_SEEN_HV_FUNC_H /* compile once */ #define PERL_SEEN_HV_FUNC_H #include "hv_macro.h" #if !( 0 \ || defined(PERL_HASH_FUNC_SIPHASH) \ || defined(PERL_HASH_FUNC_SIPHASH13) \ || defined(PERL_HASH_FUNC_STADTX) \ || defined(PERL_HASH_FUNC_ZAPHOD32) \ ) # ifdef CAN64BITHASH # define PERL_HASH_FUNC_STADTX # else # define PERL_HASH_FUNC_ZAPHOD32 # endif #endif #ifndef PERL_HASH_USE_SBOX32_ALSO #define PERL_HASH_USE_SBOX32_ALSO 1 #endif #ifndef SBOX32_MAX_LEN #define SBOX32_MAX_LEN 24 #endif /* this must be after the SBOX32_MAX_LEN define */ #include "sbox32_hash.h" #if defined(PERL_HASH_FUNC_SIPHASH) # define __PERL_HASH_FUNC "SIPHASH_2_4" # define __PERL_HASH_SEED_BYTES 16 # define __PERL_HASH_STATE_BYTES 32 # define __PERL_HASH_SEED_STATE(seed,state) S_perl_siphash_seed_state(seed,state) # define __PERL_HASH_WITH_STATE(state,str,len) S_perl_hash_siphash_2_4_with_state((state),(U8*)(str),(len)) #elif defined(PERL_HASH_FUNC_SIPHASH13) # define __PERL_HASH_FUNC "SIPHASH_1_3" # define __PERL_HASH_SEED_BYTES 16 # define __PERL_HASH_STATE_BYTES 32 # define __PERL_HASH_SEED_STATE(seed,state) S_perl_siphash_seed_state(seed,state) # define __PERL_HASH_WITH_STATE(state,str,len) S_perl_hash_siphash_1_3_with_state((state),(U8*)(str),(len)) #elif defined(PERL_HASH_FUNC_STADTX) # define __PERL_HASH_FUNC "STATDX" # define __PERL_HASH_SEED_BYTES 16 # define __PERL_HASH_STATE_BYTES 32 # define __PERL_HASH_SEED_STATE(seed,state) stadtx_seed_state(seed,state) # define __PERL_HASH_WITH_STATE(state,str,len) (U32)stadtx_hash_with_state((state),(U8*)(str),(len)) # include "stadtx_hash.h" #elif defined(PERL_HASH_FUNC_ZAPHOD32) # define __PERL_HASH_FUNC "ZAPHOD32" # define __PERL_HASH_SEED_BYTES 12 # define __PERL_HASH_STATE_BYTES 12 # define __PERL_HASH_SEED_STATE(seed,state) zaphod32_seed_state(seed,state) # define __PERL_HASH_WITH_STATE(state,str,len) (U32)zaphod32_hash_with_state((state),(U8*)(str),(len)) # include "zaphod32_hash.h" #endif #ifndef __PERL_HASH_WITH_STATE #error "No hash function defined!" #endif #ifndef __PERL_HASH_SEED_BYTES #error "__PERL_HASH_SEED_BYTES not defined" #endif #ifndef __PERL_HASH_FUNC #error "__PERL_HASH_FUNC not defined" #endif #if PERL_HASH_USE_SBOX32_ALSO != 1 # define _PERL_HASH_FUNC __PERL_HASH_FUNC # define _PERL_HASH_SEED_BYTES __PERL_HASH_SEED_BYTES # define _PERL_HASH_STATE_BYTES __PERL_HASH_STATE_BYTES # define _PERL_HASH_SEED_STATE(seed,state) __PERL_HASH_SEED_STATE(seed,state) # define _PERL_HASH_WITH_STATE(state,str,len) __PERL_HASH_WITH_STATE(state,str,len) #else #define _PERL_HASH_FUNC "SBOX32_WITH_" __PERL_HASH_FUNC #define _PERL_HASH_SEED_BYTES ( __PERL_HASH_SEED_BYTES + (int)( 3 * sizeof(U32) ) ) #define _PERL_HASH_STATE_BYTES \ ( __PERL_HASH_STATE_BYTES + ( ( 1 + ( 256 * SBOX32_MAX_LEN ) ) * sizeof(U32) ) ) #define _PERL_HASH_SEED_STATE(seed,state) STMT_START { \ __PERL_HASH_SEED_STATE(seed,state); \ sbox32_seed_state96(seed + __PERL_HASH_SEED_BYTES, state + __PERL_HASH_STATE_BYTES); \ } STMT_END #define _PERL_HASH_WITH_STATE(state,str,len) \ (LIKELY(len <= SBOX32_MAX_LEN) \ ? sbox32_hash_with_state((state + __PERL_HASH_STATE_BYTES),(U8*)(str),(len)) \ : __PERL_HASH_WITH_STATE((state),(str),(len))) #endif PERL_STATIC_INLINE U32 S_perl_hash_with_seed(const U8 * const seed, const U8 * const str, const STRLEN len) { U8 state[_PERL_HASH_STATE_BYTES]; _PERL_HASH_SEED_STATE(seed,state); return _PERL_HASH_WITH_STATE(state,str,len); } #define PERL_HASH_WITH_SEED(seed,hash,str,len) \ (hash) = S_perl_hash_with_seed((const U8 *) seed, (const U8 *) str,len) #define PERL_HASH_WITH_STATE(state,hash,str,len) \ (hash) = _PERL_HASH_WITH_STATE((state),(U8*)(str),(len)) #define PERL_HASH_SEED_STATE(seed,state) _PERL_HASH_SEED_STATE(seed,state) #define PERL_HASH_SEED_BYTES _PERL_HASH_SEED_BYTES #define PERL_HASH_STATE_BYTES _PERL_HASH_STATE_BYTES #define PERL_HASH_FUNC _PERL_HASH_FUNC #ifdef PERL_USE_SINGLE_CHAR_HASH_CACHE #define PERL_HASH(state,str,len) \ (hash) = ((len) < 2 ? ( (len) == 0 ? PL_hash_chars[256] : PL_hash_chars[(U8)(str)[0]] ) \ : _PERL_HASH_WITH_STATE(PL_hash_state,(U8*)(str),(len))) #else #define PERL_HASH(hash,str,len) \ PERL_HASH_WITH_STATE(PL_hash_state,hash,(U8*)(str),(len)) #endif /* Setup the hash seed, either we do things dynamically at start up, * including reading from the environment, or we randomly setup the * seed. The seed will be passed into the PERL_HASH_SEED_STATE() function * defined for the configuration defined for this perl, which will then * initialze whatever state it might need later in hashing. */ #ifndef PERL_HASH_SEED # if defined(USE_HASH_SEED) # define PERL_HASH_SEED PL_hash_seed # else /* this is a 512 bit seed, which should be more than enough for the * configuration of any of our hash functions (with or without sbox). * If you actually use a hard coded seed, you are strongly encouraged * to replace this with something else of the correct length * for the hash function you are using (24-32 bytes depending on build * options). Repeat, you are *STRONGLY* encouraged not to use the value * provided here. */ # define PERL_HASH_SEED \ ((const U8 *)"A long string of pseudorandomly " \ "chosen bytes for hashing in Perl") # endif #endif /* legacy - only mod_perl should be doing this. */ #ifdef PERL_HASH_INTERNAL_ACCESS #define PERL_HASH_INTERNAL(hash,str,len) PERL_HASH(hash,str,len) #endif /* 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 U32 \ FNC ## _with_state \ (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; \ case 6: b |= ( ( U64 )in[ 5] ) << 40; \ case 5: b |= ( ( U64 )in[ 4] ) << 32; \ case 4: b |= ( ( U64 )in[ 3] ) << 24; \ case 3: b |= ( ( U64 )in[ 2] ) << 16; \ case 2: b |= ( ( U64 )in[ 1] ) << 8; \ 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 (U32)(b & U32_MAX); \ } \ \ 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) */ #endif /*compile once*/ /* * ex: set ts=8 sts=4 sw=4 et: */