1// SPDX-License-Identifier: (GPL-2.0 or BSD-2-Clause) 2/* 3 * xxHash - Extremely Fast Hash algorithm 4 * Copyright (C) 2012-2016, Yann Collet. 5 * 6 * You can contact the author at: 7 * - xxHash homepage: http://cyan4973.github.io/xxHash/ 8 * - xxHash source repository: https://github.com/Cyan4973/xxHash 9 */ 10 11#include <asm/unaligned.h> 12#include <linux/errno.h> 13#include <linux/compiler.h> 14#include <linux/kernel.h> 15#include <linux/compat.h> 16#include <linux/string.h> 17#include <linux/xxhash.h> 18 19/*-************************************* 20 * Macros 21 **************************************/ 22#define xxh_rotl32(x, r) ((x << r) | (x >> (32 - r))) 23#define xxh_rotl64(x, r) ((x << r) | (x >> (64 - r))) 24 25#ifdef __LITTLE_ENDIAN 26# define XXH_CPU_LITTLE_ENDIAN 1 27#else 28# define XXH_CPU_LITTLE_ENDIAN 0 29#endif 30 31/*-************************************* 32 * Constants 33 **************************************/ 34static const uint32_t PRIME32_1 = 2654435761U; 35static const uint32_t PRIME32_2 = 2246822519U; 36static const uint32_t PRIME32_3 = 3266489917U; 37static const uint32_t PRIME32_4 = 668265263U; 38static const uint32_t PRIME32_5 = 374761393U; 39 40static const uint64_t PRIME64_1 = 11400714785074694791ULL; 41static const uint64_t PRIME64_2 = 14029467366897019727ULL; 42static const uint64_t PRIME64_3 = 1609587929392839161ULL; 43static const uint64_t PRIME64_4 = 9650029242287828579ULL; 44static const uint64_t PRIME64_5 = 2870177450012600261ULL; 45 46/*-************************** 47 * Utils 48 ***************************/ 49void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src) 50{ 51 memcpy(dst, src, sizeof(*dst)); 52} 53EXPORT_SYMBOL(xxh32_copy_state); 54 55void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src) 56{ 57 memcpy(dst, src, sizeof(*dst)); 58} 59EXPORT_SYMBOL(xxh64_copy_state); 60 61/*-*************************** 62 * Simple Hash Functions 63 ****************************/ 64static uint32_t xxh32_round(uint32_t seed, const uint32_t input) 65{ 66 seed += input * PRIME32_2; 67 seed = xxh_rotl32(seed, 13); 68 seed *= PRIME32_1; 69 return seed; 70} 71 72uint32_t xxh32(const void *input, const size_t len, const uint32_t seed) 73{ 74 const uint8_t *p = (const uint8_t *)input; 75 const uint8_t *b_end = p + len; 76 uint32_t h32; 77 78 if (len >= 16) { 79 const uint8_t *const limit = b_end - 16; 80 uint32_t v1 = seed + PRIME32_1 + PRIME32_2; 81 uint32_t v2 = seed + PRIME32_2; 82 uint32_t v3 = seed + 0; 83 uint32_t v4 = seed - PRIME32_1; 84 85 do { 86 v1 = xxh32_round(v1, get_unaligned_le32(p)); 87 p += 4; 88 v2 = xxh32_round(v2, get_unaligned_le32(p)); 89 p += 4; 90 v3 = xxh32_round(v3, get_unaligned_le32(p)); 91 p += 4; 92 v4 = xxh32_round(v4, get_unaligned_le32(p)); 93 p += 4; 94 } while (p <= limit); 95 96 h32 = xxh_rotl32(v1, 1) + xxh_rotl32(v2, 7) + 97 xxh_rotl32(v3, 12) + xxh_rotl32(v4, 18); 98 } else { 99 h32 = seed + PRIME32_5; 100 } 101 102 h32 += (uint32_t)len; 103 104 while (p + 4 <= b_end) { 105 h32 += get_unaligned_le32(p) * PRIME32_3; 106 h32 = xxh_rotl32(h32, 17) * PRIME32_4; 107 p += 4; 108 } 109 110 while (p < b_end) { 111 h32 += (*p) * PRIME32_5; 112 h32 = xxh_rotl32(h32, 11) * PRIME32_1; 113 p++; 114 } 115 116 h32 ^= h32 >> 15; 117 h32 *= PRIME32_2; 118 h32 ^= h32 >> 13; 119 h32 *= PRIME32_3; 120 h32 ^= h32 >> 16; 121 122 return h32; 123} 124EXPORT_SYMBOL(xxh32); 125 126static uint64_t xxh64_round(uint64_t acc, const uint64_t input) 127{ 128 acc += input * PRIME64_2; 129 acc = xxh_rotl64(acc, 31); 130 acc *= PRIME64_1; 131 return acc; 132} 133 134static uint64_t xxh64_merge_round(uint64_t acc, uint64_t val) 135{ 136 val = xxh64_round(0, val); 137 acc ^= val; 138 acc = acc * PRIME64_1 + PRIME64_4; 139 return acc; 140} 141 142uint64_t xxh64(const void *input, const size_t len, const uint64_t seed) 143{ 144 const uint8_t *p = (const uint8_t *)input; 145 const uint8_t *const b_end = p + len; 146 uint64_t h64; 147 148 if (len >= 32) { 149 const uint8_t *const limit = b_end - 32; 150 uint64_t v1 = seed + PRIME64_1 + PRIME64_2; 151 uint64_t v2 = seed + PRIME64_2; 152 uint64_t v3 = seed + 0; 153 uint64_t v4 = seed - PRIME64_1; 154 155 do { 156 v1 = xxh64_round(v1, get_unaligned_le64(p)); 157 p += 8; 158 v2 = xxh64_round(v2, get_unaligned_le64(p)); 159 p += 8; 160 v3 = xxh64_round(v3, get_unaligned_le64(p)); 161 p += 8; 162 v4 = xxh64_round(v4, get_unaligned_le64(p)); 163 p += 8; 164 } while (p <= limit); 165 166 h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) + 167 xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18); 168 h64 = xxh64_merge_round(h64, v1); 169 h64 = xxh64_merge_round(h64, v2); 170 h64 = xxh64_merge_round(h64, v3); 171 h64 = xxh64_merge_round(h64, v4); 172 173 } else { 174 h64 = seed + PRIME64_5; 175 } 176 177 h64 += (uint64_t)len; 178 179 while (p + 8 <= b_end) { 180 const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p)); 181 182 h64 ^= k1; 183 h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4; 184 p += 8; 185 } 186 187 if (p + 4 <= b_end) { 188 h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1; 189 h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3; 190 p += 4; 191 } 192 193 while (p < b_end) { 194 h64 ^= (*p) * PRIME64_5; 195 h64 = xxh_rotl64(h64, 11) * PRIME64_1; 196 p++; 197 } 198 199 h64 ^= h64 >> 33; 200 h64 *= PRIME64_2; 201 h64 ^= h64 >> 29; 202 h64 *= PRIME64_3; 203 h64 ^= h64 >> 32; 204 205 return h64; 206} 207EXPORT_SYMBOL(xxh64); 208 209/*-************************************************** 210 * Advanced Hash Functions 211 ***************************************************/ 212void xxh32_reset(struct xxh32_state *statePtr, const uint32_t seed) 213{ 214 /* use a local state for memcpy() to avoid strict-aliasing warnings */ 215 struct xxh32_state state; 216 217 memset(&state, 0, sizeof(state)); 218 state.v1 = seed + PRIME32_1 + PRIME32_2; 219 state.v2 = seed + PRIME32_2; 220 state.v3 = seed + 0; 221 state.v4 = seed - PRIME32_1; 222 memcpy(statePtr, &state, sizeof(state)); 223} 224EXPORT_SYMBOL(xxh32_reset); 225 226void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed) 227{ 228 /* use a local state for memcpy() to avoid strict-aliasing warnings */ 229 struct xxh64_state state; 230 231 memset(&state, 0, sizeof(state)); 232 state.v1 = seed + PRIME64_1 + PRIME64_2; 233 state.v2 = seed + PRIME64_2; 234 state.v3 = seed + 0; 235 state.v4 = seed - PRIME64_1; 236 memcpy(statePtr, &state, sizeof(state)); 237} 238EXPORT_SYMBOL(xxh64_reset); 239 240int xxh32_update(struct xxh32_state *state, const void *input, const size_t len) 241{ 242 const uint8_t *p = (const uint8_t *)input; 243 const uint8_t *const b_end = p + len; 244 245 if (input == NULL) 246 return -EINVAL; 247 248 state->total_len_32 += (uint32_t)len; 249 state->large_len |= (len >= 16) | (state->total_len_32 >= 16); 250 251 if (state->memsize + len < 16) { /* fill in tmp buffer */ 252 memcpy((uint8_t *)(state->mem32) + state->memsize, input, len); 253 state->memsize += (uint32_t)len; 254 return 0; 255 } 256 257 if (state->memsize) { /* some data left from previous update */ 258 const uint32_t *p32 = state->mem32; 259 260 memcpy((uint8_t *)(state->mem32) + state->memsize, input, 261 16 - state->memsize); 262 263 state->v1 = xxh32_round(state->v1, get_unaligned_le32(p32)); 264 p32++; 265 state->v2 = xxh32_round(state->v2, get_unaligned_le32(p32)); 266 p32++; 267 state->v3 = xxh32_round(state->v3, get_unaligned_le32(p32)); 268 p32++; 269 state->v4 = xxh32_round(state->v4, get_unaligned_le32(p32)); 270 p32++; 271 272 p += 16-state->memsize; 273 state->memsize = 0; 274 } 275 276 if (p <= b_end - 16) { 277 const uint8_t *const limit = b_end - 16; 278 uint32_t v1 = state->v1; 279 uint32_t v2 = state->v2; 280 uint32_t v3 = state->v3; 281 uint32_t v4 = state->v4; 282 283 do { 284 v1 = xxh32_round(v1, get_unaligned_le32(p)); 285 p += 4; 286 v2 = xxh32_round(v2, get_unaligned_le32(p)); 287 p += 4; 288 v3 = xxh32_round(v3, get_unaligned_le32(p)); 289 p += 4; 290 v4 = xxh32_round(v4, get_unaligned_le32(p)); 291 p += 4; 292 } while (p <= limit); 293 294 state->v1 = v1; 295 state->v2 = v2; 296 state->v3 = v3; 297 state->v4 = v4; 298 } 299 300 if (p < b_end) { 301 memcpy(state->mem32, p, (size_t)(b_end-p)); 302 state->memsize = (uint32_t)(b_end-p); 303 } 304 305 return 0; 306} 307EXPORT_SYMBOL(xxh32_update); 308 309uint32_t xxh32_digest(const struct xxh32_state *state) 310{ 311 const uint8_t *p = (const uint8_t *)state->mem32; 312 const uint8_t *const b_end = (const uint8_t *)(state->mem32) + 313 state->memsize; 314 uint32_t h32; 315 316 if (state->large_len) { 317 h32 = xxh_rotl32(state->v1, 1) + xxh_rotl32(state->v2, 7) + 318 xxh_rotl32(state->v3, 12) + xxh_rotl32(state->v4, 18); 319 } else { 320 h32 = state->v3 /* == seed */ + PRIME32_5; 321 } 322 323 h32 += state->total_len_32; 324 325 while (p + 4 <= b_end) { 326 h32 += get_unaligned_le32(p) * PRIME32_3; 327 h32 = xxh_rotl32(h32, 17) * PRIME32_4; 328 p += 4; 329 } 330 331 while (p < b_end) { 332 h32 += (*p) * PRIME32_5; 333 h32 = xxh_rotl32(h32, 11) * PRIME32_1; 334 p++; 335 } 336 337 h32 ^= h32 >> 15; 338 h32 *= PRIME32_2; 339 h32 ^= h32 >> 13; 340 h32 *= PRIME32_3; 341 h32 ^= h32 >> 16; 342 343 return h32; 344} 345EXPORT_SYMBOL(xxh32_digest); 346 347int xxh64_update(struct xxh64_state *state, const void *input, const size_t len) 348{ 349 const uint8_t *p = (const uint8_t *)input; 350 const uint8_t *const b_end = p + len; 351 352 if (input == NULL) 353 return -EINVAL; 354 355 state->total_len += len; 356 357 if (state->memsize + len < 32) { /* fill in tmp buffer */ 358 memcpy(((uint8_t *)state->mem64) + state->memsize, input, len); 359 state->memsize += (uint32_t)len; 360 return 0; 361 } 362 363 if (state->memsize) { /* tmp buffer is full */ 364 uint64_t *p64 = state->mem64; 365 366 memcpy(((uint8_t *)p64) + state->memsize, input, 367 32 - state->memsize); 368 369 state->v1 = xxh64_round(state->v1, get_unaligned_le64(p64)); 370 p64++; 371 state->v2 = xxh64_round(state->v2, get_unaligned_le64(p64)); 372 p64++; 373 state->v3 = xxh64_round(state->v3, get_unaligned_le64(p64)); 374 p64++; 375 state->v4 = xxh64_round(state->v4, get_unaligned_le64(p64)); 376 377 p += 32 - state->memsize; 378 state->memsize = 0; 379 } 380 381 if (p + 32 <= b_end) { 382 const uint8_t *const limit = b_end - 32; 383 uint64_t v1 = state->v1; 384 uint64_t v2 = state->v2; 385 uint64_t v3 = state->v3; 386 uint64_t v4 = state->v4; 387 388 do { 389 v1 = xxh64_round(v1, get_unaligned_le64(p)); 390 p += 8; 391 v2 = xxh64_round(v2, get_unaligned_le64(p)); 392 p += 8; 393 v3 = xxh64_round(v3, get_unaligned_le64(p)); 394 p += 8; 395 v4 = xxh64_round(v4, get_unaligned_le64(p)); 396 p += 8; 397 } while (p <= limit); 398 399 state->v1 = v1; 400 state->v2 = v2; 401 state->v3 = v3; 402 state->v4 = v4; 403 } 404 405 if (p < b_end) { 406 memcpy(state->mem64, p, (size_t)(b_end-p)); 407 state->memsize = (uint32_t)(b_end - p); 408 } 409 410 return 0; 411} 412EXPORT_SYMBOL(xxh64_update); 413 414uint64_t xxh64_digest(const struct xxh64_state *state) 415{ 416 const uint8_t *p = (const uint8_t *)state->mem64; 417 const uint8_t *const b_end = (const uint8_t *)state->mem64 + 418 state->memsize; 419 uint64_t h64; 420 421 if (state->total_len >= 32) { 422 const uint64_t v1 = state->v1; 423 const uint64_t v2 = state->v2; 424 const uint64_t v3 = state->v3; 425 const uint64_t v4 = state->v4; 426 427 h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) + 428 xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18); 429 h64 = xxh64_merge_round(h64, v1); 430 h64 = xxh64_merge_round(h64, v2); 431 h64 = xxh64_merge_round(h64, v3); 432 h64 = xxh64_merge_round(h64, v4); 433 } else { 434 h64 = state->v3 + PRIME64_5; 435 } 436 437 h64 += (uint64_t)state->total_len; 438 439 while (p + 8 <= b_end) { 440 const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p)); 441 442 h64 ^= k1; 443 h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4; 444 p += 8; 445 } 446 447 if (p + 4 <= b_end) { 448 h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1; 449 h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3; 450 p += 4; 451 } 452 453 while (p < b_end) { 454 h64 ^= (*p) * PRIME64_5; 455 h64 = xxh_rotl64(h64, 11) * PRIME64_1; 456 p++; 457 } 458 459 h64 ^= h64 >> 33; 460 h64 *= PRIME64_2; 461 h64 ^= h64 >> 29; 462 h64 *= PRIME64_3; 463 h64 ^= h64 >> 32; 464 465 return h64; 466} 467EXPORT_SYMBOL(xxh64_digest); 468