1 /* ========================================================================== 2 * siphash.h - SipHash-2-4 in a single header file 3 * -------------------------------------------------------------------------- 4 * Derived by William Ahern from the reference implementation[1] published[2] 5 * by Jean-Philippe Aumasson and Daniel J. Berstein. Licensed in kind. 6 * by Jean-Philippe Aumasson and Daniel J. Berstein. 7 * Minimal changes by Sebastian Pipping on top, details below. 8 * Licensed under the CC0 Public Domain Dedication license. 9 * 10 * 1. https://www.131002.net/siphash/siphash24.c 11 * 2. https://www.131002.net/siphash/ 12 * -------------------------------------------------------------------------- 13 * HISTORY: 14 * 15 * 2017-06-10 (Sebastian Pipping) 16 * - Clarify license note in the header 17 * - Address C89 issues: 18 * - Stop using inline keyword (and let compiler decide) 19 * - Turn integer suffix ULL to UL 20 * - Replace _Bool by int 21 * - Turn macro siphash24 into a function 22 * - Address invalid conversion (void pointer) by explicit cast 23 * - Always expose sip24_valid (for self-tests) 24 * 25 * 2012-11-04 - Born. (William Ahern) 26 * -------------------------------------------------------------------------- 27 * USAGE: 28 * 29 * SipHash-2-4 takes as input two 64-bit words as the key, some number of 30 * message bytes, and outputs a 64-bit word as the message digest. This 31 * implementation employs two data structures: a struct sipkey for 32 * representing the key, and a struct siphash for representing the hash 33 * state. 34 * 35 * For converting a 16-byte unsigned char array to a key, use either the 36 * macro sip_keyof or the routine sip_tokey. The former instantiates a 37 * compound literal key, while the latter requires a key object as a 38 * parameter. 39 * 40 * unsigned char secret[16]; 41 * arc4random_buf(secret, sizeof secret); 42 * struct sipkey *key = sip_keyof(secret); 43 * 44 * For hashing a message, use either the convenience macro siphash24 or the 45 * routines sip24_init, sip24_update, and sip24_final. 46 * 47 * struct siphash state; 48 * void *msg; 49 * size_t len; 50 * uint64_t hash; 51 * 52 * sip24_init(&state, key); 53 * sip24_update(&state, msg, len); 54 * hash = sip24_final(&state); 55 * 56 * or 57 * 58 * hash = siphash24(msg, len, key); 59 * 60 * To convert the 64-bit hash value to a canonical 8-byte little-endian 61 * binary representation, use either the macro sip_binof or the routine 62 * sip_tobin. The former instantiates and returns a compound literal array, 63 * while the latter requires an array object as a parameter. 64 * -------------------------------------------------------------------------- 65 * NOTES: 66 * 67 * o Neither sip_keyof, sip_binof, nor siphash24 will work with compilers 68 * lacking compound literal support. Instead, you must use the lower-level 69 * interfaces which take as parameters the temporary state objects. 70 * 71 * o Uppercase macros may evaluate parameters more than once. Lowercase 72 * macros should not exhibit any such side effects. 73 * ========================================================================== 74 */ 75 #ifndef SIPHASH_H 76 #define SIPHASH_H 77 78 #include <stddef.h> /* size_t */ 79 #include <stdint.h> /* uint64_t uint32_t uint8_t */ 80 81 82 #define SIP_ROTL(x, b) (uint64_t)(((x) << (b)) | ( (x) >> (64 - (b)))) 83 84 #define SIP_U32TO8_LE(p, v) \ 85 (p)[0] = (uint8_t)((v) >> 0); (p)[1] = (uint8_t)((v) >> 8); \ 86 (p)[2] = (uint8_t)((v) >> 16); (p)[3] = (uint8_t)((v) >> 24); 87 88 #define SIP_U64TO8_LE(p, v) \ 89 SIP_U32TO8_LE((p) + 0, (uint32_t)((v) >> 0)); \ 90 SIP_U32TO8_LE((p) + 4, (uint32_t)((v) >> 32)); 91 92 #define SIP_U8TO64_LE(p) \ 93 (((uint64_t)((p)[0]) << 0) | \ 94 ((uint64_t)((p)[1]) << 8) | \ 95 ((uint64_t)((p)[2]) << 16) | \ 96 ((uint64_t)((p)[3]) << 24) | \ 97 ((uint64_t)((p)[4]) << 32) | \ 98 ((uint64_t)((p)[5]) << 40) | \ 99 ((uint64_t)((p)[6]) << 48) | \ 100 ((uint64_t)((p)[7]) << 56)) 101 102 103 #define SIPHASH_INITIALIZER { 0, 0, 0, 0, { 0 }, 0, 0 } 104 105 struct siphash { 106 uint64_t v0, v1, v2, v3; 107 108 unsigned char buf[8], *p; 109 uint64_t c; 110 }; /* struct siphash */ 111 112 113 #define SIP_KEYLEN 16 114 115 struct sipkey { 116 uint64_t k[2]; 117 }; /* struct sipkey */ 118 119 #define sip_keyof(k) sip_tokey(&(struct sipkey){ { 0 } }, (k)) 120 121 static struct sipkey *sip_tokey(struct sipkey *key, const void *src) { 122 key->k[0] = SIP_U8TO64_LE((const unsigned char *)src); 123 key->k[1] = SIP_U8TO64_LE((const unsigned char *)src + 8); 124 return key; 125 } /* sip_tokey() */ 126 127 128 #define sip_binof(v) sip_tobin((unsigned char[8]){ 0 }, (v)) 129 130 static void *sip_tobin(void *dst, uint64_t u64) { 131 SIP_U64TO8_LE((unsigned char *)dst, u64); 132 return dst; 133 } /* sip_tobin() */ 134 135 136 static void sip_round(struct siphash *H, const int rounds) { 137 int i; 138 139 for (i = 0; i < rounds; i++) { 140 H->v0 += H->v1; 141 H->v1 = SIP_ROTL(H->v1, 13); 142 H->v1 ^= H->v0; 143 H->v0 = SIP_ROTL(H->v0, 32); 144 145 H->v2 += H->v3; 146 H->v3 = SIP_ROTL(H->v3, 16); 147 H->v3 ^= H->v2; 148 149 H->v0 += H->v3; 150 H->v3 = SIP_ROTL(H->v3, 21); 151 H->v3 ^= H->v0; 152 153 H->v2 += H->v1; 154 H->v1 = SIP_ROTL(H->v1, 17); 155 H->v1 ^= H->v2; 156 H->v2 = SIP_ROTL(H->v2, 32); 157 } 158 } /* sip_round() */ 159 160 161 static struct siphash *sip24_init(struct siphash *H, const struct sipkey *key) { 162 H->v0 = 0x736f6d6570736575UL ^ key->k[0]; 163 H->v1 = 0x646f72616e646f6dUL ^ key->k[1]; 164 H->v2 = 0x6c7967656e657261UL ^ key->k[0]; 165 H->v3 = 0x7465646279746573UL ^ key->k[1]; 166 167 H->p = H->buf; 168 H->c = 0; 169 170 return H; 171 } /* sip24_init() */ 172 173 174 #define sip_endof(a) (&(a)[sizeof (a) / sizeof *(a)]) 175 176 static struct siphash *sip24_update(struct siphash *H, const void *src, size_t len) { 177 const unsigned char *p = (const unsigned char *)src, *pe = p + len; 178 uint64_t m; 179 180 do { 181 while (p < pe && H->p < sip_endof(H->buf)) 182 *H->p++ = *p++; 183 184 if (H->p < sip_endof(H->buf)) 185 break; 186 187 m = SIP_U8TO64_LE(H->buf); 188 H->v3 ^= m; 189 sip_round(H, 2); 190 H->v0 ^= m; 191 192 H->p = H->buf; 193 H->c += 8; 194 } while (p < pe); 195 196 return H; 197 } /* sip24_update() */ 198 199 200 static uint64_t sip24_final(struct siphash *H) { 201 char left = H->p - H->buf; 202 uint64_t b = (H->c + left) << 56; 203 204 switch (left) { 205 case 7: b |= (uint64_t)H->buf[6] << 48; 206 case 6: b |= (uint64_t)H->buf[5] << 40; 207 case 5: b |= (uint64_t)H->buf[4] << 32; 208 case 4: b |= (uint64_t)H->buf[3] << 24; 209 case 3: b |= (uint64_t)H->buf[2] << 16; 210 case 2: b |= (uint64_t)H->buf[1] << 8; 211 case 1: b |= (uint64_t)H->buf[0] << 0; 212 case 0: break; 213 } 214 215 H->v3 ^= b; 216 sip_round(H, 2); 217 H->v0 ^= b; 218 H->v2 ^= 0xff; 219 sip_round(H, 4); 220 221 return H->v0 ^ H->v1 ^ H->v2 ^ H->v3; 222 } /* sip24_final() */ 223 224 225 static uint64_t siphash24(const void *src, size_t len, const struct sipkey *key) { 226 struct siphash state = SIPHASH_INITIALIZER; 227 return sip24_final(sip24_update(sip24_init(&state, key), src, len)); 228 } /* siphash24() */ 229 230 231 /* 232 * SipHash-2-4 output with 233 * k = 00 01 02 ... 234 * and 235 * in = (empty string) 236 * in = 00 (1 byte) 237 * in = 00 01 (2 bytes) 238 * in = 00 01 02 (3 bytes) 239 * ... 240 * in = 00 01 02 ... 3e (63 bytes) 241 */ 242 static int sip24_valid(void) { 243 static const unsigned char vectors[64][8] = { 244 { 0x31, 0x0e, 0x0e, 0xdd, 0x47, 0xdb, 0x6f, 0x72, }, 245 { 0xfd, 0x67, 0xdc, 0x93, 0xc5, 0x39, 0xf8, 0x74, }, 246 { 0x5a, 0x4f, 0xa9, 0xd9, 0x09, 0x80, 0x6c, 0x0d, }, 247 { 0x2d, 0x7e, 0xfb, 0xd7, 0x96, 0x66, 0x67, 0x85, }, 248 { 0xb7, 0x87, 0x71, 0x27, 0xe0, 0x94, 0x27, 0xcf, }, 249 { 0x8d, 0xa6, 0x99, 0xcd, 0x64, 0x55, 0x76, 0x18, }, 250 { 0xce, 0xe3, 0xfe, 0x58, 0x6e, 0x46, 0xc9, 0xcb, }, 251 { 0x37, 0xd1, 0x01, 0x8b, 0xf5, 0x00, 0x02, 0xab, }, 252 { 0x62, 0x24, 0x93, 0x9a, 0x79, 0xf5, 0xf5, 0x93, }, 253 { 0xb0, 0xe4, 0xa9, 0x0b, 0xdf, 0x82, 0x00, 0x9e, }, 254 { 0xf3, 0xb9, 0xdd, 0x94, 0xc5, 0xbb, 0x5d, 0x7a, }, 255 { 0xa7, 0xad, 0x6b, 0x22, 0x46, 0x2f, 0xb3, 0xf4, }, 256 { 0xfb, 0xe5, 0x0e, 0x86, 0xbc, 0x8f, 0x1e, 0x75, }, 257 { 0x90, 0x3d, 0x84, 0xc0, 0x27, 0x56, 0xea, 0x14, }, 258 { 0xee, 0xf2, 0x7a, 0x8e, 0x90, 0xca, 0x23, 0xf7, }, 259 { 0xe5, 0x45, 0xbe, 0x49, 0x61, 0xca, 0x29, 0xa1, }, 260 { 0xdb, 0x9b, 0xc2, 0x57, 0x7f, 0xcc, 0x2a, 0x3f, }, 261 { 0x94, 0x47, 0xbe, 0x2c, 0xf5, 0xe9, 0x9a, 0x69, }, 262 { 0x9c, 0xd3, 0x8d, 0x96, 0xf0, 0xb3, 0xc1, 0x4b, }, 263 { 0xbd, 0x61, 0x79, 0xa7, 0x1d, 0xc9, 0x6d, 0xbb, }, 264 { 0x98, 0xee, 0xa2, 0x1a, 0xf2, 0x5c, 0xd6, 0xbe, }, 265 { 0xc7, 0x67, 0x3b, 0x2e, 0xb0, 0xcb, 0xf2, 0xd0, }, 266 { 0x88, 0x3e, 0xa3, 0xe3, 0x95, 0x67, 0x53, 0x93, }, 267 { 0xc8, 0xce, 0x5c, 0xcd, 0x8c, 0x03, 0x0c, 0xa8, }, 268 { 0x94, 0xaf, 0x49, 0xf6, 0xc6, 0x50, 0xad, 0xb8, }, 269 { 0xea, 0xb8, 0x85, 0x8a, 0xde, 0x92, 0xe1, 0xbc, }, 270 { 0xf3, 0x15, 0xbb, 0x5b, 0xb8, 0x35, 0xd8, 0x17, }, 271 { 0xad, 0xcf, 0x6b, 0x07, 0x63, 0x61, 0x2e, 0x2f, }, 272 { 0xa5, 0xc9, 0x1d, 0xa7, 0xac, 0xaa, 0x4d, 0xde, }, 273 { 0x71, 0x65, 0x95, 0x87, 0x66, 0x50, 0xa2, 0xa6, }, 274 { 0x28, 0xef, 0x49, 0x5c, 0x53, 0xa3, 0x87, 0xad, }, 275 { 0x42, 0xc3, 0x41, 0xd8, 0xfa, 0x92, 0xd8, 0x32, }, 276 { 0xce, 0x7c, 0xf2, 0x72, 0x2f, 0x51, 0x27, 0x71, }, 277 { 0xe3, 0x78, 0x59, 0xf9, 0x46, 0x23, 0xf3, 0xa7, }, 278 { 0x38, 0x12, 0x05, 0xbb, 0x1a, 0xb0, 0xe0, 0x12, }, 279 { 0xae, 0x97, 0xa1, 0x0f, 0xd4, 0x34, 0xe0, 0x15, }, 280 { 0xb4, 0xa3, 0x15, 0x08, 0xbe, 0xff, 0x4d, 0x31, }, 281 { 0x81, 0x39, 0x62, 0x29, 0xf0, 0x90, 0x79, 0x02, }, 282 { 0x4d, 0x0c, 0xf4, 0x9e, 0xe5, 0xd4, 0xdc, 0xca, }, 283 { 0x5c, 0x73, 0x33, 0x6a, 0x76, 0xd8, 0xbf, 0x9a, }, 284 { 0xd0, 0xa7, 0x04, 0x53, 0x6b, 0xa9, 0x3e, 0x0e, }, 285 { 0x92, 0x59, 0x58, 0xfc, 0xd6, 0x42, 0x0c, 0xad, }, 286 { 0xa9, 0x15, 0xc2, 0x9b, 0xc8, 0x06, 0x73, 0x18, }, 287 { 0x95, 0x2b, 0x79, 0xf3, 0xbc, 0x0a, 0xa6, 0xd4, }, 288 { 0xf2, 0x1d, 0xf2, 0xe4, 0x1d, 0x45, 0x35, 0xf9, }, 289 { 0x87, 0x57, 0x75, 0x19, 0x04, 0x8f, 0x53, 0xa9, }, 290 { 0x10, 0xa5, 0x6c, 0xf5, 0xdf, 0xcd, 0x9a, 0xdb, }, 291 { 0xeb, 0x75, 0x09, 0x5c, 0xcd, 0x98, 0x6c, 0xd0, }, 292 { 0x51, 0xa9, 0xcb, 0x9e, 0xcb, 0xa3, 0x12, 0xe6, }, 293 { 0x96, 0xaf, 0xad, 0xfc, 0x2c, 0xe6, 0x66, 0xc7, }, 294 { 0x72, 0xfe, 0x52, 0x97, 0x5a, 0x43, 0x64, 0xee, }, 295 { 0x5a, 0x16, 0x45, 0xb2, 0x76, 0xd5, 0x92, 0xa1, }, 296 { 0xb2, 0x74, 0xcb, 0x8e, 0xbf, 0x87, 0x87, 0x0a, }, 297 { 0x6f, 0x9b, 0xb4, 0x20, 0x3d, 0xe7, 0xb3, 0x81, }, 298 { 0xea, 0xec, 0xb2, 0xa3, 0x0b, 0x22, 0xa8, 0x7f, }, 299 { 0x99, 0x24, 0xa4, 0x3c, 0xc1, 0x31, 0x57, 0x24, }, 300 { 0xbd, 0x83, 0x8d, 0x3a, 0xaf, 0xbf, 0x8d, 0xb7, }, 301 { 0x0b, 0x1a, 0x2a, 0x32, 0x65, 0xd5, 0x1a, 0xea, }, 302 { 0x13, 0x50, 0x79, 0xa3, 0x23, 0x1c, 0xe6, 0x60, }, 303 { 0x93, 0x2b, 0x28, 0x46, 0xe4, 0xd7, 0x06, 0x66, }, 304 { 0xe1, 0x91, 0x5f, 0x5c, 0xb1, 0xec, 0xa4, 0x6c, }, 305 { 0xf3, 0x25, 0x96, 0x5c, 0xa1, 0x6d, 0x62, 0x9f, }, 306 { 0x57, 0x5f, 0xf2, 0x8e, 0x60, 0x38, 0x1b, 0xe5, }, 307 { 0x72, 0x45, 0x06, 0xeb, 0x4c, 0x32, 0x8a, 0x95, } 308 }; 309 unsigned char in[64]; 310 struct sipkey k; 311 size_t i; 312 313 sip_tokey(&k, "\000\001\002\003\004\005\006\007\010\011\012\013\014\015\016\017"); 314 315 for (i = 0; i < sizeof in; ++i) { 316 in[i] = i; 317 318 if (siphash24(in, i, &k) != SIP_U8TO64_LE(vectors[i])) 319 return 0; 320 } 321 322 return 1; 323 } /* sip24_valid() */ 324 325 326 #if SIPHASH_MAIN 327 328 #include <stdio.h> 329 330 int main(void) { 331 int ok = sip24_valid(); 332 333 if (ok) 334 puts("OK"); 335 else 336 puts("FAIL"); 337 338 return !ok; 339 } /* main() */ 340 341 #endif /* SIPHASH_MAIN */ 342 343 344 #endif /* SIPHASH_H */ 345