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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_ZAPHOD32) \ ) # ifdef CAN64BITHASH # define PERL_HASH_FUNC_SIPHASH13 # 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_WORD_TYPE U64 # define __PERL_HASH_WORD_SIZE sizeof(__PERL_HASH_WORD_TYPE) # define __PERL_HASH_SEED_BYTES (__PERL_HASH_WORD_SIZE * 2) # define __PERL_HASH_STATE_BYTES (__PERL_HASH_WORD_SIZE * 4) # 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_WORD_TYPE U64 # define __PERL_HASH_WORD_SIZE sizeof(__PERL_HASH_WORD_TYPE) # define __PERL_HASH_SEED_BYTES (__PERL_HASH_WORD_SIZE * 2) # define __PERL_HASH_STATE_BYTES (__PERL_HASH_WORD_SIZE * 4) # 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_ZAPHOD32) # define __PERL_HASH_FUNC "ZAPHOD32" # define __PERL_HASH_WORD_TYPE U32 # define __PERL_HASH_WORD_SIZE sizeof(__PERL_HASH_WORD_TYPE) # define __PERL_HASH_SEED_BYTES (__PERL_HASH_WORD_SIZE * 3) # define __PERL_HASH_STATE_BYTES (__PERL_HASH_WORD_SIZE * 3) # 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 /* Some siphash static functions are needed by XS::APItest even when siphash isn't the current hash. For SipHash builds this needs to be before the S_perl_hash_with_seed() definition. */ #include "perl_siphash.h" #define __PERL_HASH_SEED_roundup(x, y) ( ( ( (x) + ( (y) - 1 ) ) / (y) ) * (y) ) #define _PERL_HASH_SEED_roundup(x) __PERL_HASH_SEED_roundup(x,__PERL_HASH_WORD_SIZE) #define PL_hash_seed ((U8 *)PL_hash_seed_w) #define PL_hash_state ((U8 *)PL_hash_state_w) #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 /* note the 4 in the below code comes from the fact the seed to initialize the SBOX is 128 bits */ #define _PERL_HASH_SEED_BYTES ( __PERL_HASH_SEED_BYTES + (int)( 4 * 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_state128(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 #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_roundup(_PERL_HASH_SEED_BYTES) #define PERL_HASH_STATE_BYTES _PERL_HASH_SEED_roundup(_PERL_HASH_STATE_BYTES) #define PERL_HASH_FUNC _PERL_HASH_FUNC #define PERL_HASH_SEED_WORDS (PERL_HASH_SEED_BYTES/__PERL_HASH_WORD_SIZE) #define PERL_HASH_STATE_WORDS (PERL_HASH_STATE_BYTES/__PERL_HASH_WORD_SIZE) #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 * initialize 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 PERL_STATIC_INLINE U32 S_perl_hash_with_seed(const U8 * seed, const U8 *str, STRLEN len) { __PERL_HASH_WORD_TYPE state[PERL_HASH_STATE_WORDS]; _PERL_HASH_SEED_STATE(seed,(U8*)state); return _PERL_HASH_WITH_STATE((U8*)state,str,len); } #endif /*compile once*/ /* * ex: set ts=8 sts=4 sw=4 et: */