2 * Copyright 2017-2020 The OpenSSL Project Authors. All Rights Reserved.
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
13 #include <openssl/evp.h>
14 #include <openssl/kdf.h>
15 #include <openssl/err.h>
16 #include <openssl/core_names.h>
17 #include "crypto/evp.h"
18 #include "internal/numbers.h"
19 #include "prov/implementations.h"
20 #include "prov/provider_ctx.h"
21 #include "prov/providercommon.h"
22 #include "prov/providercommonerr.h"
23 #include "prov/implementations.h"
25 #ifndef OPENSSL_NO_SCRYPT
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;
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);
51 uint64_t maxmem_bytes;
55 static void kdf_scrypt_init(KDF_SCRYPT *ctx);
57 static void *kdf_scrypt_new(void *provctx)
61 if (!ossl_prov_is_running())
64 ctx = OPENSSL_zalloc(sizeof(*ctx));
66 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
69 ctx->libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
74 static void kdf_scrypt_free(void *vctx)
76 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
79 OPENSSL_free(ctx->propq);
80 EVP_MD_free(ctx->sha256);
81 kdf_scrypt_reset(ctx);
86 static void kdf_scrypt_reset(void *vctx)
88 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
90 OPENSSL_free(ctx->salt);
91 OPENSSL_clear_free(ctx->pass, ctx->pass_len);
95 static void kdf_scrypt_init(KDF_SCRYPT *ctx)
97 /* Default values are the most conservative recommendation given in the
98 * original paper of C. Percival. Derivation uses roughly 1 GiB of memory
99 * for this parameter choice (approx. 128 * r * N * p bytes).
104 ctx->maxmem_bytes = 1025 * 1024 * 1024;
107 static int scrypt_set_membuf(unsigned char **buffer, size_t *buflen,
110 OPENSSL_clear_free(*buffer, *buflen);
111 if (p->data_size == 0) {
112 if ((*buffer = OPENSSL_malloc(1)) == NULL) {
113 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
116 } else if (p->data != NULL) {
118 if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
124 static int set_digest(KDF_SCRYPT *ctx)
126 EVP_MD_free(ctx->sha256);
127 ctx->sha256 = EVP_MD_fetch(ctx->libctx, "sha256", ctx->propq);
128 if (ctx->sha256 == NULL) {
130 ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256);
136 static int set_property_query(KDF_SCRYPT *ctx, const char *propq)
138 OPENSSL_free(ctx->propq);
141 ctx->propq = OPENSSL_strdup(propq);
142 if (ctx->propq == NULL) {
143 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
150 static int kdf_scrypt_derive(void *vctx, unsigned char *key,
153 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
155 if (!ossl_prov_is_running())
158 if (ctx->pass == NULL) {
159 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
163 if (ctx->salt == NULL) {
164 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
168 if (ctx->sha256 == NULL && !set_digest(ctx))
171 return scrypt_alg((char *)ctx->pass, ctx->pass_len, ctx->salt,
172 ctx->salt_len, ctx->N, ctx->r, ctx->p,
173 ctx->maxmem_bytes, key, keylen, ctx->sha256,
174 ctx->libctx, ctx->propq);
177 static int is_power_of_two(uint64_t value)
179 return (value != 0) && ((value & (value - 1)) == 0);
182 static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[])
185 KDF_SCRYPT *ctx = vctx;
188 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
189 if (!scrypt_set_membuf(&ctx->pass, &ctx->pass_len, p))
192 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL)
193 if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p))
196 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N))
198 if (!OSSL_PARAM_get_uint64(p, &u64_value)
200 || !is_power_of_two(u64_value))
205 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R))
207 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
212 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P))
214 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
219 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM))
221 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
223 ctx->maxmem_bytes = u64_value;
226 p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PROPERTIES);
228 if (p->data_type != OSSL_PARAM_UTF8_STRING
229 || !set_property_query(ctx, p->data)
236 static const OSSL_PARAM *kdf_scrypt_settable_ctx_params(ossl_unused void *p_ctx)
238 static const OSSL_PARAM known_settable_ctx_params[] = {
239 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0),
240 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
241 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N, NULL),
242 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R, NULL),
243 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P, NULL),
244 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, NULL),
245 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
248 return known_settable_ctx_params;
251 static int kdf_scrypt_get_ctx_params(void *vctx, OSSL_PARAM params[])
255 if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
256 return OSSL_PARAM_set_size_t(p, SIZE_MAX);
260 static const OSSL_PARAM *kdf_scrypt_gettable_ctx_params(ossl_unused void *p_ctx)
262 static const OSSL_PARAM known_gettable_ctx_params[] = {
263 OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
266 return known_gettable_ctx_params;
269 const OSSL_DISPATCH ossl_kdf_scrypt_functions[] = {
270 { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_scrypt_new },
271 { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_scrypt_free },
272 { OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_scrypt_reset },
273 { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_scrypt_derive },
274 { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
275 (void(*)(void))kdf_scrypt_settable_ctx_params },
276 { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_scrypt_set_ctx_params },
277 { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
278 (void(*)(void))kdf_scrypt_gettable_ctx_params },
279 { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_scrypt_get_ctx_params },
283 #define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
284 static void salsa208_word_specification(uint32_t inout[16])
289 memcpy(x, inout, sizeof(x));
290 for (i = 8; i > 0; i -= 2) {
291 x[4] ^= R(x[0] + x[12], 7);
292 x[8] ^= R(x[4] + x[0], 9);
293 x[12] ^= R(x[8] + x[4], 13);
294 x[0] ^= R(x[12] + x[8], 18);
295 x[9] ^= R(x[5] + x[1], 7);
296 x[13] ^= R(x[9] + x[5], 9);
297 x[1] ^= R(x[13] + x[9], 13);
298 x[5] ^= R(x[1] + x[13], 18);
299 x[14] ^= R(x[10] + x[6], 7);
300 x[2] ^= R(x[14] + x[10], 9);
301 x[6] ^= R(x[2] + x[14], 13);
302 x[10] ^= R(x[6] + x[2], 18);
303 x[3] ^= R(x[15] + x[11], 7);
304 x[7] ^= R(x[3] + x[15], 9);
305 x[11] ^= R(x[7] + x[3], 13);
306 x[15] ^= R(x[11] + x[7], 18);
307 x[1] ^= R(x[0] + x[3], 7);
308 x[2] ^= R(x[1] + x[0], 9);
309 x[3] ^= R(x[2] + x[1], 13);
310 x[0] ^= R(x[3] + x[2], 18);
311 x[6] ^= R(x[5] + x[4], 7);
312 x[7] ^= R(x[6] + x[5], 9);
313 x[4] ^= R(x[7] + x[6], 13);
314 x[5] ^= R(x[4] + x[7], 18);
315 x[11] ^= R(x[10] + x[9], 7);
316 x[8] ^= R(x[11] + x[10], 9);
317 x[9] ^= R(x[8] + x[11], 13);
318 x[10] ^= R(x[9] + x[8], 18);
319 x[12] ^= R(x[15] + x[14], 7);
320 x[13] ^= R(x[12] + x[15], 9);
321 x[14] ^= R(x[13] + x[12], 13);
322 x[15] ^= R(x[14] + x[13], 18);
324 for (i = 0; i < 16; ++i)
326 OPENSSL_cleanse(x, sizeof(x));
329 static void scryptBlockMix(uint32_t *B_, uint32_t *B, uint64_t r)
334 memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
336 for (i = 0; i < r * 2; i++) {
337 for (j = 0; j < 16; j++)
339 salsa208_word_specification(X);
340 memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
342 OPENSSL_cleanse(X, sizeof(X));
345 static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
346 uint32_t *X, uint32_t *T, uint32_t *V)
352 /* Convert from little endian input */
353 for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
357 *pV |= (uint32_t)*pB++ << 24;
360 for (i = 1; i < N; i++, pV += 32 * r)
361 scryptBlockMix(pV, pV - 32 * r, r);
363 scryptBlockMix(X, V + (N - 1) * 32 * r, r);
365 for (i = 0; i < N; i++) {
367 j = X[16 * (2 * r - 1)] % N;
369 for (k = 0; k < 32 * r; k++)
371 scryptBlockMix(X, T, r);
373 /* Convert output to little endian */
374 for (i = 0, pB = B; i < 32 * r; i++) {
375 uint32_t xtmp = X[i];
377 *pB++ = (xtmp >> 8) & 0xff;
378 *pB++ = (xtmp >> 16) & 0xff;
379 *pB++ = (xtmp >> 24) & 0xff;
384 # define SIZE_MAX ((size_t)-1)
388 * Maximum power of two that will fit in uint64_t: this should work on
389 * most (all?) platforms.
392 #define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1)
395 * Maximum value of p * r:
396 * p <= ((2^32-1) * hLen) / MFLen =>
397 * p <= ((2^32-1) * 32) / (128 * r) =>
401 #define SCRYPT_PR_MAX ((1 << 30) - 1)
403 static int scrypt_alg(const char *pass, size_t passlen,
404 const unsigned char *salt, size_t saltlen,
405 uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
406 unsigned char *key, size_t keylen, EVP_MD *sha256,
407 OSSL_LIB_CTX *libctx, const char *propq)
412 uint64_t i, Blen, Vlen;
414 /* Sanity check parameters */
415 /* initial check, r,p must be non zero, N >= 2 and a power of 2 */
416 if (r == 0 || p == 0 || N < 2 || (N & (N - 1)))
418 /* Check p * r < SCRYPT_PR_MAX avoiding overflow */
419 if (p > SCRYPT_PR_MAX / r) {
420 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
425 * Need to check N: if 2^(128 * r / 8) overflows limit this is
426 * automatically satisfied since N <= UINT64_MAX.
429 if (16 * r <= LOG2_UINT64_MAX) {
430 if (N >= (((uint64_t)1) << (16 * r))) {
431 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
436 /* Memory checks: check total allocated buffer size fits in uint64_t */
439 * B size in section 5 step 1.S
440 * Note: we know p * 128 * r < UINT64_MAX because we already checked
441 * p * r < SCRYPT_PR_MAX
445 * Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
446 * have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
448 if (Blen > INT_MAX) {
449 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
454 * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
455 * This is combined size V, X and T (section 4)
457 i = UINT64_MAX / (32 * sizeof(uint32_t));
459 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
462 Vlen = 32 * r * (N + 2) * sizeof(uint32_t);
464 /* check total allocated size fits in uint64_t */
465 if (Blen > UINT64_MAX - Vlen) {
466 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
470 /* Check that the maximum memory doesn't exceed a size_t limits */
471 if (maxmem > SIZE_MAX)
474 if (Blen + Vlen > maxmem) {
475 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
479 /* If no key return to indicate parameters are OK */
483 B = OPENSSL_malloc((size_t)(Blen + Vlen));
485 EVPerr(EVP_F_SCRYPT_ALG, ERR_R_MALLOC_FAILURE);
488 X = (uint32_t *)(B + Blen);
491 if (pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, 1, sha256, (int)Blen,
492 B, libctx, propq) == 0)
495 for (i = 0; i < p; i++)
496 scryptROMix(B + 128 * r * i, r, N, X, T, V);
498 if (pkcs5_pbkdf2_hmac_ex(pass, passlen, B, (int)Blen, 1, sha256, keylen,
499 key, libctx, propq) == 0)
504 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_PBKDF2_ERROR);
506 OPENSSL_clear_free(B, (size_t)(Blen + Vlen));