1 /* 2 * xxHash - Extremely Fast Hash algorithm 3 * Copyright (C) 2012-2016, Yann Collet. 4 * 5 * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are 9 * met: 10 * 11 * * Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * * Redistributions in binary form must reproduce the above 14 * copyright notice, this list of conditions and the following disclaimer 15 * in the documentation and/or other materials provided with the 16 * distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * This program is free software; you can redistribute it and/or modify it under 31 * the terms of the GNU General Public License version 2 as published by the 32 * Free Software Foundation. This program is dual-licensed; you may select 33 * either version 2 of the GNU General Public License ("GPL") or BSD license 34 * ("BSD"). 35 * 36 * You can contact the author at: 37 * - xxHash homepage: https://cyan4973.github.io/xxHash/ 38 * - xxHash source repository: https://github.com/Cyan4973/xxHash 39 */ 40 41 #include <asm/unaligned.h> 42 #include <linux/errno.h> 43 #include <linux/compiler.h> 44 #include <linux/kernel.h> 45 #include <linux/module.h> 46 #include <linux/string.h> 47 #include <linux/xxhash.h> 48 49 /*-************************************* 50 * Macros 51 **************************************/ 52 #define xxh_rotl32(x, r) ((x << r) | (x >> (32 - r))) 53 #define xxh_rotl64(x, r) ((x << r) | (x >> (64 - r))) 54 55 #ifdef __LITTLE_ENDIAN 56 # define XXH_CPU_LITTLE_ENDIAN 1 57 #else 58 # define XXH_CPU_LITTLE_ENDIAN 0 59 #endif 60 61 /*-************************************* 62 * Constants 63 **************************************/ 64 static const uint32_t PRIME32_1 = 2654435761U; 65 static const uint32_t PRIME32_2 = 2246822519U; 66 static const uint32_t PRIME32_3 = 3266489917U; 67 static const uint32_t PRIME32_4 = 668265263U; 68 static const uint32_t PRIME32_5 = 374761393U; 69 70 static const uint64_t PRIME64_1 = 11400714785074694791ULL; 71 static const uint64_t PRIME64_2 = 14029467366897019727ULL; 72 static const uint64_t PRIME64_3 = 1609587929392839161ULL; 73 static const uint64_t PRIME64_4 = 9650029242287828579ULL; 74 static const uint64_t PRIME64_5 = 2870177450012600261ULL; 75 76 /*-************************** 77 * Utils 78 ***************************/ 79 void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src) 80 { 81 memcpy(dst, src, sizeof(*dst)); 82 } 83 EXPORT_SYMBOL(xxh32_copy_state); 84 85 void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src) 86 { 87 memcpy(dst, src, sizeof(*dst)); 88 } 89 EXPORT_SYMBOL(xxh64_copy_state); 90 91 /*-*************************** 92 * Simple Hash Functions 93 ****************************/ 94 static uint32_t xxh32_round(uint32_t seed, const uint32_t input) 95 { 96 seed += input * PRIME32_2; 97 seed = xxh_rotl32(seed, 13); 98 seed *= PRIME32_1; 99 return seed; 100 } 101 102 uint32_t xxh32(const void *input, const size_t len, const uint32_t seed) 103 { 104 const uint8_t *p = (const uint8_t *)input; 105 const uint8_t *b_end = p + len; 106 uint32_t h32; 107 108 if (len >= 16) { 109 const uint8_t *const limit = b_end - 16; 110 uint32_t v1 = seed + PRIME32_1 + PRIME32_2; 111 uint32_t v2 = seed + PRIME32_2; 112 uint32_t v3 = seed + 0; 113 uint32_t v4 = seed - PRIME32_1; 114 115 do { 116 v1 = xxh32_round(v1, get_unaligned_le32(p)); 117 p += 4; 118 v2 = xxh32_round(v2, get_unaligned_le32(p)); 119 p += 4; 120 v3 = xxh32_round(v3, get_unaligned_le32(p)); 121 p += 4; 122 v4 = xxh32_round(v4, get_unaligned_le32(p)); 123 p += 4; 124 } while (p <= limit); 125 126 h32 = xxh_rotl32(v1, 1) + xxh_rotl32(v2, 7) + 127 xxh_rotl32(v3, 12) + xxh_rotl32(v4, 18); 128 } else { 129 h32 = seed + PRIME32_5; 130 } 131 132 h32 += (uint32_t)len; 133 134 while (p + 4 <= b_end) { 135 h32 += get_unaligned_le32(p) * PRIME32_3; 136 h32 = xxh_rotl32(h32, 17) * PRIME32_4; 137 p += 4; 138 } 139 140 while (p < b_end) { 141 h32 += (*p) * PRIME32_5; 142 h32 = xxh_rotl32(h32, 11) * PRIME32_1; 143 p++; 144 } 145 146 h32 ^= h32 >> 15; 147 h32 *= PRIME32_2; 148 h32 ^= h32 >> 13; 149 h32 *= PRIME32_3; 150 h32 ^= h32 >> 16; 151 152 return h32; 153 } 154 EXPORT_SYMBOL(xxh32); 155 156 static uint64_t xxh64_round(uint64_t acc, const uint64_t input) 157 { 158 acc += input * PRIME64_2; 159 acc = xxh_rotl64(acc, 31); 160 acc *= PRIME64_1; 161 return acc; 162 } 163 164 static uint64_t xxh64_merge_round(uint64_t acc, uint64_t val) 165 { 166 val = xxh64_round(0, val); 167 acc ^= val; 168 acc = acc * PRIME64_1 + PRIME64_4; 169 return acc; 170 } 171 172 uint64_t xxh64(const void *input, const size_t len, const uint64_t seed) 173 { 174 const uint8_t *p = (const uint8_t *)input; 175 const uint8_t *const b_end = p + len; 176 uint64_t h64; 177 178 if (len >= 32) { 179 const uint8_t *const limit = b_end - 32; 180 uint64_t v1 = seed + PRIME64_1 + PRIME64_2; 181 uint64_t v2 = seed + PRIME64_2; 182 uint64_t v3 = seed + 0; 183 uint64_t v4 = seed - PRIME64_1; 184 185 do { 186 v1 = xxh64_round(v1, get_unaligned_le64(p)); 187 p += 8; 188 v2 = xxh64_round(v2, get_unaligned_le64(p)); 189 p += 8; 190 v3 = xxh64_round(v3, get_unaligned_le64(p)); 191 p += 8; 192 v4 = xxh64_round(v4, get_unaligned_le64(p)); 193 p += 8; 194 } while (p <= limit); 195 196 h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) + 197 xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18); 198 h64 = xxh64_merge_round(h64, v1); 199 h64 = xxh64_merge_round(h64, v2); 200 h64 = xxh64_merge_round(h64, v3); 201 h64 = xxh64_merge_round(h64, v4); 202 203 } else { 204 h64 = seed + PRIME64_5; 205 } 206 207 h64 += (uint64_t)len; 208 209 while (p + 8 <= b_end) { 210 const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p)); 211 212 h64 ^= k1; 213 h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4; 214 p += 8; 215 } 216 217 if (p + 4 <= b_end) { 218 h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1; 219 h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3; 220 p += 4; 221 } 222 223 while (p < b_end) { 224 h64 ^= (*p) * PRIME64_5; 225 h64 = xxh_rotl64(h64, 11) * PRIME64_1; 226 p++; 227 } 228 229 h64 ^= h64 >> 33; 230 h64 *= PRIME64_2; 231 h64 ^= h64 >> 29; 232 h64 *= PRIME64_3; 233 h64 ^= h64 >> 32; 234 235 return h64; 236 } 237 EXPORT_SYMBOL(xxh64); 238 239 /*-************************************************** 240 * Advanced Hash Functions 241 ***************************************************/ 242 void xxh32_reset(struct xxh32_state *statePtr, const uint32_t seed) 243 { 244 /* use a local state for memcpy() to avoid strict-aliasing warnings */ 245 struct xxh32_state state; 246 247 memset(&state, 0, sizeof(state)); 248 state.v1 = seed + PRIME32_1 + PRIME32_2; 249 state.v2 = seed + PRIME32_2; 250 state.v3 = seed + 0; 251 state.v4 = seed - PRIME32_1; 252 memcpy(statePtr, &state, sizeof(state)); 253 } 254 EXPORT_SYMBOL(xxh32_reset); 255 256 void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed) 257 { 258 /* use a local state for memcpy() to avoid strict-aliasing warnings */ 259 struct xxh64_state state; 260 261 memset(&state, 0, sizeof(state)); 262 state.v1 = seed + PRIME64_1 + PRIME64_2; 263 state.v2 = seed + PRIME64_2; 264 state.v3 = seed + 0; 265 state.v4 = seed - PRIME64_1; 266 memcpy(statePtr, &state, sizeof(state)); 267 } 268 EXPORT_SYMBOL(xxh64_reset); 269 270 int xxh32_update(struct xxh32_state *state, const void *input, const size_t len) 271 { 272 const uint8_t *p = (const uint8_t *)input; 273 const uint8_t *const b_end = p + len; 274 275 if (input == NULL) 276 return -EINVAL; 277 278 state->total_len_32 += (uint32_t)len; 279 state->large_len |= (len >= 16) | (state->total_len_32 >= 16); 280 281 if (state->memsize + len < 16) { /* fill in tmp buffer */ 282 memcpy((uint8_t *)(state->mem32) + state->memsize, input, len); 283 state->memsize += (uint32_t)len; 284 return 0; 285 } 286 287 if (state->memsize) { /* some data left from previous update */ 288 const uint32_t *p32 = state->mem32; 289 290 memcpy((uint8_t *)(state->mem32) + state->memsize, input, 291 16 - state->memsize); 292 293 state->v1 = xxh32_round(state->v1, get_unaligned_le32(p32)); 294 p32++; 295 state->v2 = xxh32_round(state->v2, get_unaligned_le32(p32)); 296 p32++; 297 state->v3 = xxh32_round(state->v3, get_unaligned_le32(p32)); 298 p32++; 299 state->v4 = xxh32_round(state->v4, get_unaligned_le32(p32)); 300 p32++; 301 302 p += 16-state->memsize; 303 state->memsize = 0; 304 } 305 306 if (p <= b_end - 16) { 307 const uint8_t *const limit = b_end - 16; 308 uint32_t v1 = state->v1; 309 uint32_t v2 = state->v2; 310 uint32_t v3 = state->v3; 311 uint32_t v4 = state->v4; 312 313 do { 314 v1 = xxh32_round(v1, get_unaligned_le32(p)); 315 p += 4; 316 v2 = xxh32_round(v2, get_unaligned_le32(p)); 317 p += 4; 318 v3 = xxh32_round(v3, get_unaligned_le32(p)); 319 p += 4; 320 v4 = xxh32_round(v4, get_unaligned_le32(p)); 321 p += 4; 322 } while (p <= limit); 323 324 state->v1 = v1; 325 state->v2 = v2; 326 state->v3 = v3; 327 state->v4 = v4; 328 } 329 330 if (p < b_end) { 331 memcpy(state->mem32, p, (size_t)(b_end-p)); 332 state->memsize = (uint32_t)(b_end-p); 333 } 334 335 return 0; 336 } 337 EXPORT_SYMBOL(xxh32_update); 338 339 uint32_t xxh32_digest(const struct xxh32_state *state) 340 { 341 const uint8_t *p = (const uint8_t *)state->mem32; 342 const uint8_t *const b_end = (const uint8_t *)(state->mem32) + 343 state->memsize; 344 uint32_t h32; 345 346 if (state->large_len) { 347 h32 = xxh_rotl32(state->v1, 1) + xxh_rotl32(state->v2, 7) + 348 xxh_rotl32(state->v3, 12) + xxh_rotl32(state->v4, 18); 349 } else { 350 h32 = state->v3 /* == seed */ + PRIME32_5; 351 } 352 353 h32 += state->total_len_32; 354 355 while (p + 4 <= b_end) { 356 h32 += get_unaligned_le32(p) * PRIME32_3; 357 h32 = xxh_rotl32(h32, 17) * PRIME32_4; 358 p += 4; 359 } 360 361 while (p < b_end) { 362 h32 += (*p) * PRIME32_5; 363 h32 = xxh_rotl32(h32, 11) * PRIME32_1; 364 p++; 365 } 366 367 h32 ^= h32 >> 15; 368 h32 *= PRIME32_2; 369 h32 ^= h32 >> 13; 370 h32 *= PRIME32_3; 371 h32 ^= h32 >> 16; 372 373 return h32; 374 } 375 EXPORT_SYMBOL(xxh32_digest); 376 377 int xxh64_update(struct xxh64_state *state, const void *input, const size_t len) 378 { 379 const uint8_t *p = (const uint8_t *)input; 380 const uint8_t *const b_end = p + len; 381 382 if (input == NULL) 383 return -EINVAL; 384 385 state->total_len += len; 386 387 if (state->memsize + len < 32) { /* fill in tmp buffer */ 388 memcpy(((uint8_t *)state->mem64) + state->memsize, input, len); 389 state->memsize += (uint32_t)len; 390 return 0; 391 } 392 393 if (state->memsize) { /* tmp buffer is full */ 394 uint64_t *p64 = state->mem64; 395 396 memcpy(((uint8_t *)p64) + state->memsize, input, 397 32 - state->memsize); 398 399 state->v1 = xxh64_round(state->v1, get_unaligned_le64(p64)); 400 p64++; 401 state->v2 = xxh64_round(state->v2, get_unaligned_le64(p64)); 402 p64++; 403 state->v3 = xxh64_round(state->v3, get_unaligned_le64(p64)); 404 p64++; 405 state->v4 = xxh64_round(state->v4, get_unaligned_le64(p64)); 406 407 p += 32 - state->memsize; 408 state->memsize = 0; 409 } 410 411 if (p + 32 <= b_end) { 412 const uint8_t *const limit = b_end - 32; 413 uint64_t v1 = state->v1; 414 uint64_t v2 = state->v2; 415 uint64_t v3 = state->v3; 416 uint64_t v4 = state->v4; 417 418 do { 419 v1 = xxh64_round(v1, get_unaligned_le64(p)); 420 p += 8; 421 v2 = xxh64_round(v2, get_unaligned_le64(p)); 422 p += 8; 423 v3 = xxh64_round(v3, get_unaligned_le64(p)); 424 p += 8; 425 v4 = xxh64_round(v4, get_unaligned_le64(p)); 426 p += 8; 427 } while (p <= limit); 428 429 state->v1 = v1; 430 state->v2 = v2; 431 state->v3 = v3; 432 state->v4 = v4; 433 } 434 435 if (p < b_end) { 436 memcpy(state->mem64, p, (size_t)(b_end-p)); 437 state->memsize = (uint32_t)(b_end - p); 438 } 439 440 return 0; 441 } 442 EXPORT_SYMBOL(xxh64_update); 443 444 uint64_t xxh64_digest(const struct xxh64_state *state) 445 { 446 const uint8_t *p = (const uint8_t *)state->mem64; 447 const uint8_t *const b_end = (const uint8_t *)state->mem64 + 448 state->memsize; 449 uint64_t h64; 450 451 if (state->total_len >= 32) { 452 const uint64_t v1 = state->v1; 453 const uint64_t v2 = state->v2; 454 const uint64_t v3 = state->v3; 455 const uint64_t v4 = state->v4; 456 457 h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) + 458 xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18); 459 h64 = xxh64_merge_round(h64, v1); 460 h64 = xxh64_merge_round(h64, v2); 461 h64 = xxh64_merge_round(h64, v3); 462 h64 = xxh64_merge_round(h64, v4); 463 } else { 464 h64 = state->v3 + PRIME64_5; 465 } 466 467 h64 += (uint64_t)state->total_len; 468 469 while (p + 8 <= b_end) { 470 const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p)); 471 472 h64 ^= k1; 473 h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4; 474 p += 8; 475 } 476 477 if (p + 4 <= b_end) { 478 h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1; 479 h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3; 480 p += 4; 481 } 482 483 while (p < b_end) { 484 h64 ^= (*p) * PRIME64_5; 485 h64 = xxh_rotl64(h64, 11) * PRIME64_1; 486 p++; 487 } 488 489 h64 ^= h64 >> 33; 490 h64 *= PRIME64_2; 491 h64 ^= h64 >> 29; 492 h64 *= PRIME64_3; 493 h64 ^= h64 >> 32; 494 495 return h64; 496 } 497 EXPORT_SYMBOL(xxh64_digest); 498 499 MODULE_LICENSE("Dual BSD/GPL"); 500 MODULE_DESCRIPTION("xxHash"); 501