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Restore "Move utility macros to their own file"
[perl5.git] / hv_func.h
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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
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7 * (see also perl.c:perl_parse() and S_init_tls_and_interp() and util.c:get_hash_seed())
8 */
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9#ifndef PERL_SEEN_HV_FUNC_H /* compile once */
10#define PERL_SEEN_HV_FUNC_H
1c4b2386 11#include "hv_macro.h"
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12
13#if !( 0 \
14 || defined(PERL_HASH_FUNC_SIPHASH) \
15 || defined(PERL_HASH_FUNC_SIPHASH13) \
16 || defined(PERL_HASH_FUNC_STADTX) \
17 || defined(PERL_HASH_FUNC_ZAPHOD32) \
18 )
19# ifdef CAN64BITHASH
20# define PERL_HASH_FUNC_STADTX
21# else
22# define PERL_HASH_FUNC_ZAPHOD32
23# endif
24#endif
25
26#ifndef PERL_HASH_USE_SBOX32_ALSO
27#define PERL_HASH_USE_SBOX32_ALSO 1
28#endif
29
30#ifndef SBOX32_MAX_LEN
31#define SBOX32_MAX_LEN 24
32#endif
33
34/* this must be after the SBOX32_MAX_LEN define */
35#include "sbox32_hash.h"
36
37#if defined(PERL_HASH_FUNC_SIPHASH)
38# define __PERL_HASH_FUNC "SIPHASH_2_4"
39# define __PERL_HASH_SEED_BYTES 16
40# define __PERL_HASH_STATE_BYTES 32
41# define __PERL_HASH_SEED_STATE(seed,state) S_perl_siphash_seed_state(seed,state)
42# define __PERL_HASH_WITH_STATE(state,str,len) S_perl_hash_siphash_2_4_with_state((state),(U8*)(str),(len))
43#elif defined(PERL_HASH_FUNC_SIPHASH13)
44# define __PERL_HASH_FUNC "SIPHASH_1_3"
45# define __PERL_HASH_SEED_BYTES 16
46# define __PERL_HASH_STATE_BYTES 32
47# define __PERL_HASH_SEED_STATE(seed,state) S_perl_siphash_seed_state(seed,state)
48# define __PERL_HASH_WITH_STATE(state,str,len) S_perl_hash_siphash_1_3_with_state((state),(U8*)(str),(len))
49#elif defined(PERL_HASH_FUNC_STADTX)
50# define __PERL_HASH_FUNC "STATDX"
51# define __PERL_HASH_SEED_BYTES 16
52# define __PERL_HASH_STATE_BYTES 32
53# define __PERL_HASH_SEED_STATE(seed,state) stadtx_seed_state(seed,state)
54# define __PERL_HASH_WITH_STATE(state,str,len) (U32)stadtx_hash_with_state((state),(U8*)(str),(len))
55# include "stadtx_hash.h"
56#elif defined(PERL_HASH_FUNC_ZAPHOD32)
57# define __PERL_HASH_FUNC "ZAPHOD32"
58# define __PERL_HASH_SEED_BYTES 12
59# define __PERL_HASH_STATE_BYTES 12
60# define __PERL_HASH_SEED_STATE(seed,state) zaphod32_seed_state(seed,state)
61# define __PERL_HASH_WITH_STATE(state,str,len) (U32)zaphod32_hash_with_state((state),(U8*)(str),(len))
62# include "zaphod32_hash.h"
63#endif
64
65#ifndef __PERL_HASH_WITH_STATE
66#error "No hash function defined!"
67#endif
68#ifndef __PERL_HASH_SEED_BYTES
69#error "__PERL_HASH_SEED_BYTES not defined"
70#endif
71#ifndef __PERL_HASH_FUNC
72#error "__PERL_HASH_FUNC not defined"
73#endif
74
75
76#if PERL_HASH_USE_SBOX32_ALSO == 1
77# define _PERL_HASH_FUNC __PERL_HASH_FUNC
78# define _PERL_HASH_SEED_BYTES __PERL_HASH_SEED_BYTES
79# define _PERL_HASH_STATE_BYTES __PERL_HASH_STATE_BYTES
80# define _PERL_HASH_SEED_STATE(seed,state) __PERL_HASH_SEED_STATE(seed,state)
81# define _PERL_HASH_WITH_STATE(state,str,len) __PERL_HASH_WITH_STATE(state,str,len)
82#else
83
84#define _PERL_HASH_FUNC "SBOX32_WITH_" __PERL_HASH_FUNC
85
86#define _PERL_HASH_SEED_BYTES ( __PERL_HASH_SEED_BYTES + ( 3 * sizeof(U32) ) )
87
88#define _PERL_HASH_STATE_BYTES \
89 ( __PERL_HASH_SEED_BYTES + ( ( 1 + ( 256 * SBOX32_MAX_LEN ) ) * sizeof(U32) ) )
90
91#define _PERL_HASH_SEED_STATE(seed,state) STMT_START { \
92 __PERL_HASH_SEED_STATE(seed,state); \
93 sbox32_seed_state96(seed + __PERL_HASH_SEED_BYTES , state + __PERL_HASH_STATE_BYTES); \
94} STMT_END
95
96#define _PERL_HASH_WITH_STATE(state,str,len) \
97 ((len <= SBOX32_MAX_LEN) \
98 ? sbox32_hash_with_state((state + __PERL_HASH_STATE_BYTES),(U8*)(str),(len)) \
99 : __PERL_HASH_WITH_STATE((state),(str),(len)))
100
101#endif
102
103PERL_STATIC_INLINE
104U32 S_perl_hash_with_seed(const U8 * const seed, const U8 * const str, const STRLEN len)
105{
106 U8 state[_PERL_HASH_STATE_BYTES];
107 _PERL_HASH_SEED_STATE(seed,state);
108 return _PERL_HASH_WITH_STATE(state,str,len);
109}
110
111#define PERL_HASH_WITH_SEED(seed,hash,str,len) \
112 (hash) = S_perl_hash_with_seed(seed,str,len)
113#define PERL_HASH_WITH_STATE(state,hash,str,len) \
114 (hash) = _PERL_HASH_WITH_STATE((state),(U8*)(str),(len))
115#define PERL_HASH_SEED_STATE(seed,state) _PERL_HASH_SEED_STATE(seed,state)
116#define PERL_HASH_SEED_BYTES _PERL_HASH_SEED_BYTES
117#define PERL_HASH_STATE_BYTES _PERL_HASH_STATE_BYTES
118#define PERL_HASH_FUNC _PERL_HASH_FUNC
119
120#ifdef PERL_USE_SINGLE_CHAR_HASH_CACHE
121#define PERL_HASH(state,str,len) \
122 (hash) = ((len) < 2 ? ( (len) == 0 ? PL_hash_chars[256] : PL_hash_chars[(U8)(str)[0]] ) \
123 : _PERL_HASH_WITH_STATE(PL_hash_state,(U8*)(str),(len)))
124#else
125#define PERL_HASH(hash,str,len) \
126 PERL_HASH_WITH_STATE(PL_hash_state,hash,(U8*)(str),(len))
127#endif
128
129/* Setup the hash seed, either we do things dynamically at start up,
130 * including reading from the environment, or we randomly setup the
131 * seed. The seed will be passed into the PERL_HASH_SEED_STATE() function
132 * defined for the configuration defined for this perl, which will then
133 * initialze whatever state it might need later in hashing. */
134
135#ifndef PERL_HASH_SEED
136# if defined(USE_HASH_SEED) || defined(USE_HASH_SEED_EXPLICIT)
137# define PERL_HASH_SEED PL_hash_seed
138# else
139 /* this is a 512 bit seed, which should be more than enough for the
140 * configuration of any of our hash functions (with or without sbox).
141 * If you actually use a hard coded seed, you are strongly encouraged
142 * to replace this with something else of the correct length
143 * for the hash function you are using (24-32 bytes depending on build
144 * options). Repeat, you are *STRONGLY* encouraged not to use the value
145 * provided here.
146 */
147# define PERL_HASH_SEED \
148 ((const U8 *)"A long string of pseudorandomly " \
149 "chosen bytes for hashing in Perl")
150# endif
151#endif
152
153/* legacy - only mod_perl should be doing this. */
154#ifdef PERL_HASH_INTERNAL_ACCESS
155#define PERL_HASH_INTERNAL(hash,str,len) PERL_HASH(hash,str,len)
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156#endif
157
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158/* This is SipHash by Jean-Philippe Aumasson and Daniel J. Bernstein.
159 * The authors claim it is relatively secure compared to the alternatives
160 * and that performance wise it is a suitable hash for languages like Perl.
161 * See:
162 *
163 * https://www.131002.net/siphash/
164 *
165 * This implementation seems to perform slightly slower than one-at-a-time for
166 * short keys, but degrades slower for longer keys. Murmur Hash outperforms it
167 * regardless of keys size.
168 *
169 * It is 64 bit only.
170 */
171
4d8c7823 172#ifdef CAN64BITHASH
4d3a042d 173
4d3a042d 174#define SIPROUND \
6b026047 175 STMT_START { \
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176 v0 += v1; v1=ROTL64(v1,13); v1 ^= v0; v0=ROTL64(v0,32); \
177 v2 += v3; v3=ROTL64(v3,16); v3 ^= v2; \
178 v0 += v3; v3=ROTL64(v3,21); v3 ^= v0; \
179 v2 += v1; v1=ROTL64(v1,17); v1 ^= v2; v2=ROTL64(v2,32); \
6b026047 180 } STMT_END
4d3a042d 181
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182#define SIPHASH_SEED_STATE(key,v0,v1,v2,v3) \
183do { \
184 v0 = v2 = U8TO64_LE(key + 0); \
185 v1 = v3 = U8TO64_LE(key + 8); \
186 /* "somepseudorandomlygeneratedbytes" */ \
187 v0 ^= 0x736f6d6570736575ull; \
188 v1 ^= 0x646f72616e646f6dull; \
189 v2 ^= 0x6c7967656e657261ull; \
190 v3 ^= 0x7465646279746573ull; \
191} while (0)
192
193PERL_STATIC_INLINE
194void S_perl_siphash_seed_state(const unsigned char * const seed_buf, unsigned char * state_buf) {
195 U64 *v= (U64*) state_buf;
196 SIPHASH_SEED_STATE(seed_buf, v[0],v[1],v[2],v[3]);
197}
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198
199#define PERL_SIPHASH_FNC(FNC,SIP_ROUNDS,SIP_FINAL_ROUNDS) \
200PERL_STATIC_INLINE U32 \
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201FNC ## _with_state \
202 (const unsigned char * const state, const unsigned char *in, const STRLEN inlen) \
203{ \
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204 const int left = inlen & 7; \
205 const U8 *end = in + inlen - left; \
206 \
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207 U64 b = ( ( U64 )(inlen) ) << 56; \
208 U64 m; \
209 U64 v0 = U8TO64_LE(state); \
210 U64 v1 = U8TO64_LE(state+8); \
211 U64 v2 = U8TO64_LE(state+16); \
212 U64 v3 = U8TO64_LE(state+24); \
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213 \
214 for ( ; in != end; in += 8 ) \
215 { \
216 m = U8TO64_LE( in ); \
217 v3 ^= m; \
218 \
219 SIP_ROUNDS; \
220 \
221 v0 ^= m; \
222 } \
223 \
224 switch( left ) \
225 { \
226 case 7: b |= ( ( U64 )in[ 6] ) << 48; \
227 case 6: b |= ( ( U64 )in[ 5] ) << 40; \
228 case 5: b |= ( ( U64 )in[ 4] ) << 32; \
229 case 4: b |= ( ( U64 )in[ 3] ) << 24; \
230 case 3: b |= ( ( U64 )in[ 2] ) << 16; \
231 case 2: b |= ( ( U64 )in[ 1] ) << 8; \
232 case 1: b |= ( ( U64 )in[ 0] ); break; \
233 case 0: break; \
234 } \
235 \
236 v3 ^= b; \
237 \
238 SIP_ROUNDS; \
239 \
240 v0 ^= b; \
241 \
242 v2 ^= 0xff; \
243 \
244 SIP_FINAL_ROUNDS \
245 \
246 b = v0 ^ v1 ^ v2 ^ v3; \
247 return (U32)(b & U32_MAX); \
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248} \
249 \
250PERL_STATIC_INLINE U32 \
251FNC (const unsigned char * const seed, const unsigned char *in, const STRLEN inlen) \
252{ \
253 U64 state[4]; \
254 SIPHASH_SEED_STATE(seed,state[0],state[1],state[2],state[3]); \
255 return FNC ## _with_state((U8*)state,in,inlen); \
4d3a042d 256}
6b026047 257
9d5e3f1a 258
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259PERL_SIPHASH_FNC(
260 S_perl_hash_siphash_1_3
261 ,SIPROUND;
262 ,SIPROUND;SIPROUND;SIPROUND;
263)
264
265PERL_SIPHASH_FNC(
266 S_perl_hash_siphash_2_4
267 ,SIPROUND;SIPROUND;
268 ,SIPROUND;SIPROUND;SIPROUND;SIPROUND;
269)
4d8c7823 270#endif /* defined(CAN64BITHASH) */
4d3a042d 271
6b026047 272
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273
274
275
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276#endif /*compile once*/
277
278/*
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279 * ex: set ts=8 sts=4 sw=4 et:
280 */