2 * Copyright 2017-2019 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 "internal/evp_int.h"
18 #include "internal/numbers.h"
19 #include "internal/provider_algs.h"
20 #include "internal/provider_ctx.h"
21 #include "internal/providercommonerr.h"
22 #include "internal/provider_algs.h"
24 #ifndef OPENSSL_NO_SCRYPT
26 static OSSL_OP_kdf_newctx_fn kdf_scrypt_new;
27 static OSSL_OP_kdf_freectx_fn kdf_scrypt_free;
28 static OSSL_OP_kdf_reset_fn kdf_scrypt_reset;
29 static OSSL_OP_kdf_derive_fn kdf_scrypt_derive;
30 static OSSL_OP_kdf_settable_ctx_params_fn kdf_scrypt_settable_ctx_params;
31 static OSSL_OP_kdf_set_ctx_params_fn kdf_scrypt_set_ctx_params;
33 static int scrypt_alg(const char *pass, size_t passlen,
34 const unsigned char *salt, size_t saltlen,
35 uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
36 unsigned char *key, size_t keylen, EVP_MD *sha256);
46 uint64_t maxmem_bytes;
50 static void kdf_scrypt_init(KDF_SCRYPT *ctx);
52 static void *kdf_scrypt_new(void *provctx)
56 ctx = OPENSSL_zalloc(sizeof(*ctx));
58 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
61 ctx->provctx = provctx;
62 ctx->sha256 = EVP_MD_fetch(PROV_LIBRARY_CONTEXT_OF(provctx),
64 if (ctx->sha256 == NULL) {
66 ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256);
73 static void kdf_scrypt_free(void *vctx)
75 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
77 kdf_scrypt_reset(ctx);
78 EVP_MD_meth_free(ctx->sha256);
82 static void kdf_scrypt_reset(void *vctx)
84 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
86 OPENSSL_free(ctx->salt);
87 OPENSSL_clear_free(ctx->pass, ctx->pass_len);
88 memset(ctx, 0, sizeof(*ctx));
92 static void kdf_scrypt_init(KDF_SCRYPT *ctx)
94 /* Default values are the most conservative recommendation given in the
95 * original paper of C. Percival. Derivation uses roughly 1 GiB of memory
96 * for this parameter choice (approx. 128 * r * N * p bytes).
101 ctx->maxmem_bytes = 1025 * 1024 * 1024;
104 static int scrypt_set_membuf(unsigned char **buffer, size_t *buflen,
107 OPENSSL_clear_free(*buffer, *buflen);
108 if (p->data_size == 0) {
109 if ((*buffer = OPENSSL_malloc(1)) == NULL) {
110 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
113 } else if (p->data != NULL) {
115 if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
121 static int kdf_scrypt_derive(void *vctx, unsigned char *key,
124 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
126 if (ctx->pass == NULL) {
127 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
131 if (ctx->salt == NULL) {
132 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
136 return scrypt_alg((char *)ctx->pass, ctx->pass_len, ctx->salt,
137 ctx->salt_len, ctx->N, ctx->r, ctx->p,
138 ctx->maxmem_bytes, key, keylen, ctx->sha256);
141 static int is_power_of_two(uint64_t value)
143 return (value != 0) && ((value & (value - 1)) == 0);
146 static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[])
149 KDF_SCRYPT *ctx = vctx;
152 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
153 if (!scrypt_set_membuf(&ctx->pass, &ctx->pass_len, p))
156 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL)
157 if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p))
160 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N))
162 if (!OSSL_PARAM_get_uint64(p, &u64_value)
164 || !is_power_of_two(u64_value))
169 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R))
171 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
176 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P))
178 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
183 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM))
185 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
187 ctx->maxmem_bytes = u64_value;
192 static const OSSL_PARAM *kdf_scrypt_settable_ctx_params(void)
194 static const OSSL_PARAM known_settable_ctx_params[] = {
195 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0),
196 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
197 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N, NULL),
198 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R, NULL),
199 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P, NULL),
200 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, NULL),
203 return known_settable_ctx_params;
206 static int kdf_scrypt_get_ctx_params(void *vctx, OSSL_PARAM params[])
210 if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
211 return OSSL_PARAM_set_size_t(p, SIZE_MAX);
215 static const OSSL_PARAM *kdf_scrypt_gettable_ctx_params(void)
217 static const OSSL_PARAM known_gettable_ctx_params[] = {
218 OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
221 return known_gettable_ctx_params;
224 const OSSL_DISPATCH kdf_scrypt_functions[] = {
225 { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_scrypt_new },
226 { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_scrypt_free },
227 { OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_scrypt_reset },
228 { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_scrypt_derive },
229 { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
230 (void(*)(void))kdf_scrypt_settable_ctx_params },
231 { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_scrypt_set_ctx_params },
232 { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
233 (void(*)(void))kdf_scrypt_gettable_ctx_params },
234 { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_scrypt_get_ctx_params },
238 #define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
239 static void salsa208_word_specification(uint32_t inout[16])
244 memcpy(x, inout, sizeof(x));
245 for (i = 8; i > 0; i -= 2) {
246 x[4] ^= R(x[0] + x[12], 7);
247 x[8] ^= R(x[4] + x[0], 9);
248 x[12] ^= R(x[8] + x[4], 13);
249 x[0] ^= R(x[12] + x[8], 18);
250 x[9] ^= R(x[5] + x[1], 7);
251 x[13] ^= R(x[9] + x[5], 9);
252 x[1] ^= R(x[13] + x[9], 13);
253 x[5] ^= R(x[1] + x[13], 18);
254 x[14] ^= R(x[10] + x[6], 7);
255 x[2] ^= R(x[14] + x[10], 9);
256 x[6] ^= R(x[2] + x[14], 13);
257 x[10] ^= R(x[6] + x[2], 18);
258 x[3] ^= R(x[15] + x[11], 7);
259 x[7] ^= R(x[3] + x[15], 9);
260 x[11] ^= R(x[7] + x[3], 13);
261 x[15] ^= R(x[11] + x[7], 18);
262 x[1] ^= R(x[0] + x[3], 7);
263 x[2] ^= R(x[1] + x[0], 9);
264 x[3] ^= R(x[2] + x[1], 13);
265 x[0] ^= R(x[3] + x[2], 18);
266 x[6] ^= R(x[5] + x[4], 7);
267 x[7] ^= R(x[6] + x[5], 9);
268 x[4] ^= R(x[7] + x[6], 13);
269 x[5] ^= R(x[4] + x[7], 18);
270 x[11] ^= R(x[10] + x[9], 7);
271 x[8] ^= R(x[11] + x[10], 9);
272 x[9] ^= R(x[8] + x[11], 13);
273 x[10] ^= R(x[9] + x[8], 18);
274 x[12] ^= R(x[15] + x[14], 7);
275 x[13] ^= R(x[12] + x[15], 9);
276 x[14] ^= R(x[13] + x[12], 13);
277 x[15] ^= R(x[14] + x[13], 18);
279 for (i = 0; i < 16; ++i)
281 OPENSSL_cleanse(x, sizeof(x));
284 static void scryptBlockMix(uint32_t *B_, uint32_t *B, uint64_t r)
289 memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
291 for (i = 0; i < r * 2; i++) {
292 for (j = 0; j < 16; j++)
294 salsa208_word_specification(X);
295 memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
297 OPENSSL_cleanse(X, sizeof(X));
300 static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
301 uint32_t *X, uint32_t *T, uint32_t *V)
307 /* Convert from little endian input */
308 for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
312 *pV |= (uint32_t)*pB++ << 24;
315 for (i = 1; i < N; i++, pV += 32 * r)
316 scryptBlockMix(pV, pV - 32 * r, r);
318 scryptBlockMix(X, V + (N - 1) * 32 * r, r);
320 for (i = 0; i < N; i++) {
322 j = X[16 * (2 * r - 1)] % N;
324 for (k = 0; k < 32 * r; k++)
326 scryptBlockMix(X, T, r);
328 /* Convert output to little endian */
329 for (i = 0, pB = B; i < 32 * r; i++) {
330 uint32_t xtmp = X[i];
332 *pB++ = (xtmp >> 8) & 0xff;
333 *pB++ = (xtmp >> 16) & 0xff;
334 *pB++ = (xtmp >> 24) & 0xff;
339 # define SIZE_MAX ((size_t)-1)
343 * Maximum power of two that will fit in uint64_t: this should work on
344 * most (all?) platforms.
347 #define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1)
350 * Maximum value of p * r:
351 * p <= ((2^32-1) * hLen) / MFLen =>
352 * p <= ((2^32-1) * 32) / (128 * r) =>
356 #define SCRYPT_PR_MAX ((1 << 30) - 1)
358 static int scrypt_alg(const char *pass, size_t passlen,
359 const unsigned char *salt, size_t saltlen,
360 uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
361 unsigned char *key, size_t keylen, EVP_MD *sha256)
366 uint64_t i, Blen, Vlen;
368 /* Sanity check parameters */
369 /* initial check, r,p must be non zero, N >= 2 and a power of 2 */
370 if (r == 0 || p == 0 || N < 2 || (N & (N - 1)))
372 /* Check p * r < SCRYPT_PR_MAX avoiding overflow */
373 if (p > SCRYPT_PR_MAX / r) {
374 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
379 * Need to check N: if 2^(128 * r / 8) overflows limit this is
380 * automatically satisfied since N <= UINT64_MAX.
383 if (16 * r <= LOG2_UINT64_MAX) {
384 if (N >= (((uint64_t)1) << (16 * r))) {
385 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
390 /* Memory checks: check total allocated buffer size fits in uint64_t */
393 * B size in section 5 step 1.S
394 * Note: we know p * 128 * r < UINT64_MAX because we already checked
395 * p * r < SCRYPT_PR_MAX
399 * Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
400 * have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
402 if (Blen > INT_MAX) {
403 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
408 * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
409 * This is combined size V, X and T (section 4)
411 i = UINT64_MAX / (32 * sizeof(uint32_t));
413 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
416 Vlen = 32 * r * (N + 2) * sizeof(uint32_t);
418 /* check total allocated size fits in uint64_t */
419 if (Blen > UINT64_MAX - Vlen) {
420 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
424 /* Check that the maximum memory doesn't exceed a size_t limits */
425 if (maxmem > SIZE_MAX)
428 if (Blen + Vlen > maxmem) {
429 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_MEMORY_LIMIT_EXCEEDED);
433 /* If no key return to indicate parameters are OK */
437 B = OPENSSL_malloc((size_t)(Blen + Vlen));
439 EVPerr(EVP_F_SCRYPT_ALG, ERR_R_MALLOC_FAILURE);
442 X = (uint32_t *)(B + Blen);
445 if (PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, 1, sha256,
449 for (i = 0; i < p; i++)
450 scryptROMix(B + 128 * r * i, r, N, X, T, V);
452 if (PKCS5_PBKDF2_HMAC(pass, passlen, B, (int)Blen, 1, sha256,
458 EVPerr(EVP_F_SCRYPT_ALG, EVP_R_PBKDF2_ERROR);
460 OPENSSL_clear_free(B, (size_t)(Blen + Vlen));