1 /* hash a key 2 *-------------------------------------------------------------------------------------- 3 * The "hash seed" feature was added in Perl 5.8.1 to perturb the results 4 * to avoid "algorithmic complexity attacks". 5 * 6 * If USE_HASH_SEED is defined, hash randomisation is done by default 7 * (see also perl.c:perl_parse() and S_init_tls_and_interp() and util.c:get_hash_seed()) 8 */ 9 #ifndef PERL_SEEN_HV_FUNC_H_ /* compile once */ 10 #define PERL_SEEN_HV_FUNC_H_ 11 #include "hv_macro.h" 12 13 #if !( 0 \ 14 || defined(PERL_HASH_FUNC_SIPHASH) \ 15 || defined(PERL_HASH_FUNC_SIPHASH13) \ 16 || defined(PERL_HASH_FUNC_ZAPHOD32) \ 17 ) 18 # ifdef CAN64BITHASH 19 # define PERL_HASH_FUNC_SIPHASH13 20 # else 21 # define PERL_HASH_FUNC_ZAPHOD32 22 # endif 23 #endif 24 25 #ifndef PERL_HASH_USE_SBOX32_ALSO 26 # if defined(PERL_HASH_USE_SBOX32) || !defined(PERL_HASH_NO_SBOX32) 27 # define PERL_HASH_USE_SBOX32_ALSO 1 28 # else 29 # define PERL_HASH_USE_SBOX32_ALSO 0 30 # endif 31 #endif 32 33 #undef PERL_HASH_USE_SBOX32 34 #undef PERL_HASH_NO_SBOX32 35 #if PERL_HASH_USE_SBOX32_ALSO != 0 36 # define PERL_HASH_USE_SBOX32 37 #else 38 # define PERL_HASH_NO_SBOX32 39 #endif 40 41 #ifndef SBOX32_MAX_LEN 42 #define SBOX32_MAX_LEN 24 43 #endif 44 45 /* this must be after the SBOX32_MAX_LEN define */ 46 #include "sbox32_hash.h" 47 48 #if defined(PERL_HASH_FUNC_SIPHASH) 49 # define PERL_HASH_FUNC_DEFINE "PERL_HASH_FUNC_SIPHASH" 50 # define PVT__PERL_HASH_FUNC "SIPHASH_2_4" 51 # define PVT__PERL_HASH_WORD_TYPE U64 52 # define PVT__PERL_HASH_WORD_SIZE sizeof(PVT__PERL_HASH_WORD_TYPE) 53 # define PVT__PERL_HASH_SEED_BYTES (PVT__PERL_HASH_WORD_SIZE * 2) 54 # define PVT__PERL_HASH_STATE_BYTES (PVT__PERL_HASH_WORD_SIZE * 4) 55 # define PVT__PERL_HASH_SEED_STATE(seed,state) S_perl_siphash_seed_state(seed,state) 56 # define PVT__PERL_HASH_WITH_STATE(state,str,len) S_perl_hash_siphash_2_4_with_state((state),(U8*)(str),(len)) 57 #elif defined(PERL_HASH_FUNC_SIPHASH13) 58 # define PERL_HASH_FUNC_DEFINE "PERL_HASH_FUNC_SIPHASH13" 59 # define PVT__PERL_HASH_FUNC "SIPHASH_1_3" 60 # define PVT__PERL_HASH_WORD_TYPE U64 61 # define PVT__PERL_HASH_WORD_SIZE sizeof(PVT__PERL_HASH_WORD_TYPE) 62 # define PVT__PERL_HASH_SEED_BYTES (PVT__PERL_HASH_WORD_SIZE * 2) 63 # define PVT__PERL_HASH_STATE_BYTES (PVT__PERL_HASH_WORD_SIZE * 4) 64 # define PVT__PERL_HASH_SEED_STATE(seed,state) S_perl_siphash_seed_state(seed,state) 65 # define PVT__PERL_HASH_WITH_STATE(state,str,len) S_perl_hash_siphash_1_3_with_state((state),(const U8*)(str),(len)) 66 #elif defined(PERL_HASH_FUNC_ZAPHOD32) 67 # define PERL_HASH_FUNC_DEFINE "PERL_HASH_FUNC_ZAPHOD32" 68 # define PVT__PERL_HASH_FUNC "ZAPHOD32" 69 # define PVT__PERL_HASH_WORD_TYPE U32 70 # define PVT__PERL_HASH_WORD_SIZE sizeof(PVT__PERL_HASH_WORD_TYPE) 71 # define PVT__PERL_HASH_SEED_BYTES (PVT__PERL_HASH_WORD_SIZE * 3) 72 # define PVT__PERL_HASH_STATE_BYTES (PVT__PERL_HASH_WORD_SIZE * 3) 73 # define PVT__PERL_HASH_SEED_STATE(seed,state) zaphod32_seed_state(seed,state) 74 # define PVT__PERL_HASH_WITH_STATE(state,str,len) (U32)zaphod32_hash_with_state((state),(U8*)(str),(len)) 75 # include "zaphod32_hash.h" 76 #endif 77 78 #ifndef PVT__PERL_HASH_WITH_STATE 79 #error "No hash function defined!" 80 #endif 81 #ifndef PVT__PERL_HASH_SEED_BYTES 82 #error "PVT__PERL_HASH_SEED_BYTES not defined" 83 #endif 84 #ifndef PVT__PERL_HASH_FUNC 85 #error "PVT__PERL_HASH_FUNC not defined" 86 #endif 87 88 /* Some siphash static functions are needed by XS::APItest even when 89 siphash isn't the current hash. For SipHash builds this needs to 90 be before the S_perl_hash_with_seed() definition. 91 */ 92 #include "perl_siphash.h" 93 94 #define PVT__PERL_HASH_SEED_roundup(x, y) ( ( ( (x) + ( (y) - 1 ) ) / (y) ) * (y) ) 95 #define PVT_PERL_HASH_SEED_roundup(x) PVT__PERL_HASH_SEED_roundup(x,PVT__PERL_HASH_WORD_SIZE) 96 97 #define PL_hash_seed ((U8 *)PL_hash_seed_w) 98 #define PL_hash_state ((U8 *)PL_hash_state_w) 99 100 #if PERL_HASH_USE_SBOX32_ALSO == 0 101 # define PVT_PERL_HASH_FUNC PVT__PERL_HASH_FUNC 102 # define PVT_PERL_HASH_SEED_BYTES PVT__PERL_HASH_SEED_BYTES 103 # define PVT_PERL_HASH_STATE_BYTES PVT__PERL_HASH_STATE_BYTES 104 # define PVT_PERL_HASH_SEED_STATE(seed,state) PVT__PERL_HASH_SEED_STATE(seed,state) 105 # define PVT_PERL_HASH_WITH_STATE(state,str,len) PVT__PERL_HASH_WITH_STATE(state,str,len) 106 #else 107 108 #define PVT_PERL_HASH_FUNC "SBOX32_WITH_" PVT__PERL_HASH_FUNC 109 /* note the 4 in the below code comes from the fact the seed to initialize the SBOX is 128 bits */ 110 #define PVT_PERL_HASH_SEED_BYTES ( PVT__PERL_HASH_SEED_BYTES + (int)( 4 * sizeof(U32)) ) 111 112 #define PVT_PERL_HASH_STATE_BYTES \ 113 ( PVT__PERL_HASH_STATE_BYTES + ( ( 1 + ( 256 * SBOX32_MAX_LEN ) ) * sizeof(U32) ) ) 114 115 #define PVT_PERL_HASH_SEED_STATE(seed,state) STMT_START { \ 116 PVT__PERL_HASH_SEED_STATE(seed,state); \ 117 sbox32_seed_state128(seed + PVT__PERL_HASH_SEED_BYTES, state + PVT__PERL_HASH_STATE_BYTES); \ 118 } STMT_END 119 120 #define PVT_PERL_HASH_WITH_STATE(state,str,len) \ 121 (LIKELY(len <= SBOX32_MAX_LEN) \ 122 ? sbox32_hash_with_state((state + PVT__PERL_HASH_STATE_BYTES),(const U8*)(str),(len)) \ 123 : PVT__PERL_HASH_WITH_STATE((state),(str),(len))) 124 125 #endif 126 127 #define PERL_HASH_WITH_SEED(seed,hash,str,len) \ 128 (hash) = S_perl_hash_with_seed((const U8 *) seed, (const U8 *) str,len) 129 #define PERL_HASH_WITH_STATE(state,hash,str,len) \ 130 (hash) = PVT_PERL_HASH_WITH_STATE((state),(const U8*)(str),(len)) 131 132 #define PERL_HASH_SEED_STATE(seed,state) PVT_PERL_HASH_SEED_STATE(seed,state) 133 #define PERL_HASH_SEED_BYTES PVT_PERL_HASH_SEED_roundup(PVT_PERL_HASH_SEED_BYTES) 134 #define PERL_HASH_STATE_BYTES PVT_PERL_HASH_SEED_roundup(PVT_PERL_HASH_STATE_BYTES) 135 #define PERL_HASH_FUNC PVT_PERL_HASH_FUNC 136 137 #define PERL_HASH_SEED_WORDS (PERL_HASH_SEED_BYTES/PVT__PERL_HASH_WORD_SIZE) 138 #define PERL_HASH_STATE_WORDS (PERL_HASH_STATE_BYTES/PVT__PERL_HASH_WORD_SIZE) 139 140 #ifdef PERL_USE_SINGLE_CHAR_HASH_CACHE 141 #define PERL_HASH(state,str,len) \ 142 (hash) = ((len) < 2 ? ( (len) == 0 ? PL_hash_chars[256] : PL_hash_chars[(U8)(str)[0]] ) \ 143 : PVT_PERL_HASH_WITH_STATE(PL_hash_state,(U8*)(str),(len))) 144 #else 145 #define PERL_HASH(hash,str,len) \ 146 PERL_HASH_WITH_STATE(PL_hash_state,hash,(U8*)(str),(len)) 147 #endif 148 149 /* Setup the hash seed, either we do things dynamically at start up, 150 * including reading from the environment, or we randomly setup the 151 * seed. The seed will be passed into the PERL_HASH_SEED_STATE() function 152 * defined for the configuration defined for this perl, which will then 153 * initialize whatever state it might need later in hashing. */ 154 155 #ifndef PERL_HASH_SEED 156 # if defined(USE_HASH_SEED) 157 # define PERL_HASH_SEED PL_hash_seed 158 # else 159 /* this is a 512 bit seed, which should be more than enough for the 160 * configuration of any of our hash functions (with or without sbox). 161 * If you actually use a hard coded seed, you are strongly encouraged 162 * to replace this with something else of the correct length 163 * for the hash function you are using (24-32 bytes depending on build 164 * options). Repeat, you are *STRONGLY* encouraged not to use the value 165 * provided here. 166 */ 167 # define PERL_HASH_SEED \ 168 ((const U8 *)"A long string of pseudorandomly " \ 169 "chosen bytes for hashing in Perl") 170 # endif 171 #endif 172 173 /* legacy - only mod_perl should be doing this. */ 174 #ifdef PERL_HASH_INTERNAL_ACCESS 175 #define PERL_HASH_INTERNAL(hash,str,len) PERL_HASH(hash,str,len) 176 #endif 177 178 PERL_STATIC_INLINE U32 179 S_perl_hash_with_seed(const U8 * seed, const U8 *str, STRLEN len) { 180 PVT__PERL_HASH_WORD_TYPE state[PERL_HASH_STATE_WORDS]; 181 PVT_PERL_HASH_SEED_STATE(seed,(U8*)state); 182 return PVT_PERL_HASH_WITH_STATE((U8*)state,str,len); 183 } 184 185 #endif /*compile once*/ 186 187 /* 188 * ex: set ts=8 sts=4 sw=4 et: 189 */ 190