1 /* 2 * Copyright 2017-2025 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include <stdlib.h> 11 #include <stdarg.h> 12 #include <string.h> 13 #include <openssl/evp.h> 14 #include <openssl/kdf.h> 15 #include <openssl/err.h> 16 #include <openssl/core_names.h> 17 #include <openssl/proverr.h> 18 #include "crypto/evp.h" 19 #include "internal/numbers.h" 20 #include "prov/implementations.h" 21 #include "prov/provider_ctx.h" 22 #include "prov/providercommon.h" 23 #include "prov/implementations.h" 24 25 #ifndef OPENSSL_NO_SCRYPT 26 27 static OSSL_FUNC_kdf_newctx_fn kdf_scrypt_new; 28 static OSSL_FUNC_kdf_freectx_fn kdf_scrypt_free; 29 static OSSL_FUNC_kdf_reset_fn kdf_scrypt_reset; 30 static OSSL_FUNC_kdf_derive_fn kdf_scrypt_derive; 31 static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_scrypt_settable_ctx_params; 32 static OSSL_FUNC_kdf_set_ctx_params_fn kdf_scrypt_set_ctx_params; 33 static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_scrypt_gettable_ctx_params; 34 static OSSL_FUNC_kdf_get_ctx_params_fn kdf_scrypt_get_ctx_params; 35 36 static int scrypt_alg(const char *pass, size_t passlen, 37 const unsigned char *salt, size_t saltlen, 38 uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem, 39 unsigned char *key, size_t keylen, EVP_MD *sha256, 40 OSSL_LIB_CTX *libctx, const char *propq); 41 42 typedef struct { 43 OSSL_LIB_CTX *libctx; 44 char *propq; 45 unsigned char *pass; 46 size_t pass_len; 47 unsigned char *salt; 48 size_t salt_len; 49 uint64_t N; 50 uint64_t r, p; 51 uint64_t maxmem_bytes; 52 EVP_MD *sha256; 53 } KDF_SCRYPT; 54 55 static void kdf_scrypt_init(KDF_SCRYPT *ctx); 56 57 static void *kdf_scrypt_new(void *provctx) 58 { 59 KDF_SCRYPT *ctx; 60 61 if (!ossl_prov_is_running()) 62 return NULL; 63 64 ctx = OPENSSL_zalloc(sizeof(*ctx)); 65 if (ctx == NULL) { 66 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE); 67 return NULL; 68 } 69 ctx->libctx = PROV_LIBCTX_OF(provctx); 70 kdf_scrypt_init(ctx); 71 return ctx; 72 } 73 74 static void kdf_scrypt_free(void *vctx) 75 { 76 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx; 77 78 if (ctx != NULL) { 79 OPENSSL_free(ctx->propq); 80 EVP_MD_free(ctx->sha256); 81 kdf_scrypt_reset(ctx); 82 OPENSSL_free(ctx); 83 } 84 } 85 86 static void kdf_scrypt_reset(void *vctx) 87 { 88 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx; 89 90 OPENSSL_free(ctx->salt); 91 ctx->salt = NULL; 92 OPENSSL_clear_free(ctx->pass, ctx->pass_len); 93 ctx->pass = NULL; 94 kdf_scrypt_init(ctx); 95 } 96 97 static void kdf_scrypt_init(KDF_SCRYPT *ctx) 98 { 99 /* Default values are the most conservative recommendation given in the 100 * original paper of C. Percival. Derivation uses roughly 1 GiB of memory 101 * for this parameter choice (approx. 128 * r * N * p bytes). 102 */ 103 ctx->N = 1 << 20; 104 ctx->r = 8; 105 ctx->p = 1; 106 ctx->maxmem_bytes = 1025 * 1024 * 1024; 107 } 108 109 static int scrypt_set_membuf(unsigned char **buffer, size_t *buflen, 110 const OSSL_PARAM *p) 111 { 112 OPENSSL_clear_free(*buffer, *buflen); 113 *buffer = NULL; 114 *buflen = 0; 115 116 if (p->data_size == 0) { 117 if ((*buffer = OPENSSL_malloc(1)) == NULL) { 118 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE); 119 return 0; 120 } 121 } else if (p->data != NULL) { 122 if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen)) 123 return 0; 124 } 125 return 1; 126 } 127 128 static int set_digest(KDF_SCRYPT *ctx) 129 { 130 EVP_MD_free(ctx->sha256); 131 ctx->sha256 = EVP_MD_fetch(ctx->libctx, "sha256", ctx->propq); 132 if (ctx->sha256 == NULL) { 133 ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256); 134 return 0; 135 } 136 return 1; 137 } 138 139 static int set_property_query(KDF_SCRYPT *ctx, const char *propq) 140 { 141 OPENSSL_free(ctx->propq); 142 ctx->propq = NULL; 143 if (propq != NULL) { 144 ctx->propq = OPENSSL_strdup(propq); 145 if (ctx->propq == NULL) { 146 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE); 147 return 0; 148 } 149 } 150 return 1; 151 } 152 153 static int kdf_scrypt_derive(void *vctx, unsigned char *key, size_t keylen, 154 const OSSL_PARAM params[]) 155 { 156 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx; 157 158 if (!ossl_prov_is_running() || !kdf_scrypt_set_ctx_params(ctx, params)) 159 return 0; 160 161 if (ctx->pass == NULL) { 162 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS); 163 return 0; 164 } 165 166 if (ctx->salt == NULL) { 167 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT); 168 return 0; 169 } 170 171 if (ctx->sha256 == NULL && !set_digest(ctx)) 172 return 0; 173 174 return scrypt_alg((char *)ctx->pass, ctx->pass_len, ctx->salt, 175 ctx->salt_len, ctx->N, ctx->r, ctx->p, 176 ctx->maxmem_bytes, key, keylen, ctx->sha256, 177 ctx->libctx, ctx->propq); 178 } 179 180 static int is_power_of_two(uint64_t value) 181 { 182 return (value != 0) && ((value & (value - 1)) == 0); 183 } 184 185 static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[]) 186 { 187 const OSSL_PARAM *p; 188 KDF_SCRYPT *ctx = vctx; 189 uint64_t u64_value; 190 191 if (params == NULL) 192 return 1; 193 194 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL) 195 if (!scrypt_set_membuf(&ctx->pass, &ctx->pass_len, p)) 196 return 0; 197 198 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL) 199 if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p)) 200 return 0; 201 202 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N)) 203 != NULL) { 204 if (!OSSL_PARAM_get_uint64(p, &u64_value) 205 || u64_value <= 1 206 || !is_power_of_two(u64_value)) 207 return 0; 208 ctx->N = u64_value; 209 } 210 211 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R)) 212 != NULL) { 213 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1) 214 return 0; 215 ctx->r = u64_value; 216 } 217 218 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P)) 219 != NULL) { 220 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1) 221 return 0; 222 ctx->p = u64_value; 223 } 224 225 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM)) 226 != NULL) { 227 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1) 228 return 0; 229 ctx->maxmem_bytes = u64_value; 230 } 231 232 p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PROPERTIES); 233 if (p != NULL) { 234 if (p->data_type != OSSL_PARAM_UTF8_STRING 235 || !set_property_query(ctx, p->data) 236 || !set_digest(ctx)) 237 return 0; 238 } 239 return 1; 240 } 241 242 static const OSSL_PARAM *kdf_scrypt_settable_ctx_params(ossl_unused void *ctx, 243 ossl_unused void *p_ctx) 244 { 245 static const OSSL_PARAM known_settable_ctx_params[] = { 246 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0), 247 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0), 248 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N, NULL), 249 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R, NULL), 250 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P, NULL), 251 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, NULL), 252 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0), 253 OSSL_PARAM_END 254 }; 255 return known_settable_ctx_params; 256 } 257 258 static int kdf_scrypt_get_ctx_params(void *vctx, OSSL_PARAM params[]) 259 { 260 OSSL_PARAM *p; 261 262 if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL) 263 return OSSL_PARAM_set_size_t(p, SIZE_MAX); 264 return -2; 265 } 266 267 static const OSSL_PARAM *kdf_scrypt_gettable_ctx_params(ossl_unused void *ctx, 268 ossl_unused void *p_ctx) 269 { 270 static const OSSL_PARAM known_gettable_ctx_params[] = { 271 OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL), 272 OSSL_PARAM_END 273 }; 274 return known_gettable_ctx_params; 275 } 276 277 const OSSL_DISPATCH ossl_kdf_scrypt_functions[] = { 278 { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_scrypt_new }, 279 { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_scrypt_free }, 280 { OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_scrypt_reset }, 281 { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_scrypt_derive }, 282 { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS, 283 (void(*)(void))kdf_scrypt_settable_ctx_params }, 284 { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_scrypt_set_ctx_params }, 285 { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS, 286 (void(*)(void))kdf_scrypt_gettable_ctx_params }, 287 { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_scrypt_get_ctx_params }, 288 { 0, NULL } 289 }; 290 291 #define R(a,b) (((a) << (b)) | ((a) >> (32 - (b)))) 292 static void salsa208_word_specification(uint32_t inout[16]) 293 { 294 int i; 295 uint32_t x[16]; 296 297 memcpy(x, inout, sizeof(x)); 298 for (i = 8; i > 0; i -= 2) { 299 x[4] ^= R(x[0] + x[12], 7); 300 x[8] ^= R(x[4] + x[0], 9); 301 x[12] ^= R(x[8] + x[4], 13); 302 x[0] ^= R(x[12] + x[8], 18); 303 x[9] ^= R(x[5] + x[1], 7); 304 x[13] ^= R(x[9] + x[5], 9); 305 x[1] ^= R(x[13] + x[9], 13); 306 x[5] ^= R(x[1] + x[13], 18); 307 x[14] ^= R(x[10] + x[6], 7); 308 x[2] ^= R(x[14] + x[10], 9); 309 x[6] ^= R(x[2] + x[14], 13); 310 x[10] ^= R(x[6] + x[2], 18); 311 x[3] ^= R(x[15] + x[11], 7); 312 x[7] ^= R(x[3] + x[15], 9); 313 x[11] ^= R(x[7] + x[3], 13); 314 x[15] ^= R(x[11] + x[7], 18); 315 x[1] ^= R(x[0] + x[3], 7); 316 x[2] ^= R(x[1] + x[0], 9); 317 x[3] ^= R(x[2] + x[1], 13); 318 x[0] ^= R(x[3] + x[2], 18); 319 x[6] ^= R(x[5] + x[4], 7); 320 x[7] ^= R(x[6] + x[5], 9); 321 x[4] ^= R(x[7] + x[6], 13); 322 x[5] ^= R(x[4] + x[7], 18); 323 x[11] ^= R(x[10] + x[9], 7); 324 x[8] ^= R(x[11] + x[10], 9); 325 x[9] ^= R(x[8] + x[11], 13); 326 x[10] ^= R(x[9] + x[8], 18); 327 x[12] ^= R(x[15] + x[14], 7); 328 x[13] ^= R(x[12] + x[15], 9); 329 x[14] ^= R(x[13] + x[12], 13); 330 x[15] ^= R(x[14] + x[13], 18); 331 } 332 for (i = 0; i < 16; ++i) 333 inout[i] += x[i]; 334 OPENSSL_cleanse(x, sizeof(x)); 335 } 336 337 static void scryptBlockMix(uint32_t *B_, uint32_t *B, uint64_t r) 338 { 339 uint64_t i, j; 340 uint32_t X[16], *pB; 341 342 memcpy(X, B + (r * 2 - 1) * 16, sizeof(X)); 343 pB = B; 344 for (i = 0; i < r * 2; i++) { 345 for (j = 0; j < 16; j++) 346 X[j] ^= *pB++; 347 salsa208_word_specification(X); 348 memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X)); 349 } 350 OPENSSL_cleanse(X, sizeof(X)); 351 } 352 353 static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N, 354 uint32_t *X, uint32_t *T, uint32_t *V) 355 { 356 unsigned char *pB; 357 uint32_t *pV; 358 uint64_t i, k; 359 360 /* Convert from little endian input */ 361 for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) { 362 *pV = *pB++; 363 *pV |= *pB++ << 8; 364 *pV |= *pB++ << 16; 365 *pV |= (uint32_t)*pB++ << 24; 366 } 367 368 for (i = 1; i < N; i++, pV += 32 * r) 369 scryptBlockMix(pV, pV - 32 * r, r); 370 371 scryptBlockMix(X, V + (N - 1) * 32 * r, r); 372 373 for (i = 0; i < N; i++) { 374 uint32_t j; 375 j = X[16 * (2 * r - 1)] % N; 376 pV = V + 32 * r * j; 377 for (k = 0; k < 32 * r; k++) 378 T[k] = X[k] ^ *pV++; 379 scryptBlockMix(X, T, r); 380 } 381 /* Convert output to little endian */ 382 for (i = 0, pB = B; i < 32 * r; i++) { 383 uint32_t xtmp = X[i]; 384 *pB++ = xtmp & 0xff; 385 *pB++ = (xtmp >> 8) & 0xff; 386 *pB++ = (xtmp >> 16) & 0xff; 387 *pB++ = (xtmp >> 24) & 0xff; 388 } 389 } 390 391 #ifndef SIZE_MAX 392 # define SIZE_MAX ((size_t)-1) 393 #endif 394 395 /* 396 * Maximum power of two that will fit in uint64_t: this should work on 397 * most (all?) platforms. 398 */ 399 400 #define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1) 401 402 /* 403 * Maximum value of p * r: 404 * p <= ((2^32-1) * hLen) / MFLen => 405 * p <= ((2^32-1) * 32) / (128 * r) => 406 * p * r <= (2^30-1) 407 */ 408 409 #define SCRYPT_PR_MAX ((1 << 30) - 1) 410 411 static int scrypt_alg(const char *pass, size_t passlen, 412 const unsigned char *salt, size_t saltlen, 413 uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem, 414 unsigned char *key, size_t keylen, EVP_MD *sha256, 415 OSSL_LIB_CTX *libctx, const char *propq) 416 { 417 int rv = 0; 418 unsigned char *B; 419 uint32_t *X, *V, *T; 420 uint64_t i, Blen, Vlen; 421 422 /* Sanity check parameters */ 423 /* initial check, r,p must be non zero, N >= 2 and a power of 2 */ 424 if (r == 0 || p == 0 || N < 2 || (N & (N - 1))) 425 return 0; 426 /* Check p * r < SCRYPT_PR_MAX avoiding overflow */ 427 if (p > SCRYPT_PR_MAX / r) { 428 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED); 429 return 0; 430 } 431 432 /* 433 * Need to check N: if 2^(128 * r / 8) overflows limit this is 434 * automatically satisfied since N <= UINT64_MAX. 435 */ 436 437 if (16 * r <= LOG2_UINT64_MAX) { 438 if (N >= (((uint64_t)1) << (16 * r))) { 439 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED); 440 return 0; 441 } 442 } 443 444 /* Memory checks: check total allocated buffer size fits in uint64_t */ 445 446 /* 447 * B size in section 5 step 1.S 448 * Note: we know p * 128 * r < UINT64_MAX because we already checked 449 * p * r < SCRYPT_PR_MAX 450 */ 451 Blen = p * 128 * r; 452 /* 453 * Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would 454 * have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.] 455 */ 456 if (Blen > INT_MAX) { 457 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED); 458 return 0; 459 } 460 461 /* 462 * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t 463 * This is combined size V, X and T (section 4) 464 */ 465 i = UINT64_MAX / (32 * sizeof(uint32_t)); 466 if (N + 2 > i / r) { 467 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED); 468 return 0; 469 } 470 Vlen = 32 * r * (N + 2) * sizeof(uint32_t); 471 472 /* check total allocated size fits in uint64_t */ 473 if (Blen > UINT64_MAX - Vlen) { 474 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED); 475 return 0; 476 } 477 478 /* Check that the maximum memory doesn't exceed a size_t limits */ 479 if (maxmem > SIZE_MAX) 480 maxmem = SIZE_MAX; 481 482 if (Blen + Vlen > maxmem) { 483 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED); 484 return 0; 485 } 486 487 /* If no key return to indicate parameters are OK */ 488 if (key == NULL) 489 return 1; 490 491 B = OPENSSL_malloc((size_t)(Blen + Vlen)); 492 if (B == NULL) { 493 ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE); 494 return 0; 495 } 496 X = (uint32_t *)(B + Blen); 497 T = X + 32 * r; 498 V = T + 32 * r; 499 if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, 1, sha256, 500 (int)Blen, B, libctx, propq) == 0) 501 goto err; 502 503 for (i = 0; i < p; i++) 504 scryptROMix(B + 128 * r * i, r, N, X, T, V); 505 506 if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, B, (int)Blen, 1, sha256, 507 keylen, key, libctx, propq) == 0) 508 goto err; 509 rv = 1; 510 err: 511 if (rv == 0) 512 ERR_raise(ERR_LIB_EVP, EVP_R_PBKDF2_ERROR); 513 514 OPENSSL_clear_free(B, (size_t)(Blen + Vlen)); 515 return rv; 516 } 517 518 #endif 519