2 * Copyright 2017-2021 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 <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"
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_LIBCTX_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
);
114 if (p
->data_size
== 0) {
115 if ((*buffer
= OPENSSL_malloc(1)) == NULL
) {
116 ERR_raise(ERR_LIB_PROV
, ERR_R_MALLOC_FAILURE
);
119 } else if (p
->data
!= NULL
) {
120 if (!OSSL_PARAM_get_octet_string(p
, (void **)buffer
, 0, buflen
))
126 static int set_digest(KDF_SCRYPT
*ctx
)
128 EVP_MD_free(ctx
->sha256
);
129 ctx
->sha256
= EVP_MD_fetch(ctx
->libctx
, "sha256", ctx
->propq
);
130 if (ctx
->sha256
== NULL
) {
132 ERR_raise(ERR_LIB_PROV
, PROV_R_UNABLE_TO_LOAD_SHA256
);
138 static int set_property_query(KDF_SCRYPT
*ctx
, const char *propq
)
140 OPENSSL_free(ctx
->propq
);
143 ctx
->propq
= OPENSSL_strdup(propq
);
144 if (ctx
->propq
== NULL
) {
145 ERR_raise(ERR_LIB_PROV
, ERR_R_MALLOC_FAILURE
);
152 static int kdf_scrypt_derive(void *vctx
, unsigned char *key
, size_t keylen
,
153 const OSSL_PARAM params
[])
155 KDF_SCRYPT
*ctx
= (KDF_SCRYPT
*)vctx
;
157 if (!ossl_prov_is_running() || !kdf_scrypt_set_ctx_params(ctx
, params
))
160 if (ctx
->pass
== NULL
) {
161 ERR_raise(ERR_LIB_PROV
, PROV_R_MISSING_PASS
);
165 if (ctx
->salt
== NULL
) {
166 ERR_raise(ERR_LIB_PROV
, PROV_R_MISSING_SALT
);
170 if (ctx
->sha256
== NULL
&& !set_digest(ctx
))
173 return scrypt_alg((char *)ctx
->pass
, ctx
->pass_len
, ctx
->salt
,
174 ctx
->salt_len
, ctx
->N
, ctx
->r
, ctx
->p
,
175 ctx
->maxmem_bytes
, key
, keylen
, ctx
->sha256
,
176 ctx
->libctx
, ctx
->propq
);
179 static int is_power_of_two(uint64_t value
)
181 return (value
!= 0) && ((value
& (value
- 1)) == 0);
184 static int kdf_scrypt_set_ctx_params(void *vctx
, const OSSL_PARAM params
[])
187 KDF_SCRYPT
*ctx
= vctx
;
193 if ((p
= OSSL_PARAM_locate_const(params
, OSSL_KDF_PARAM_PASSWORD
)) != NULL
)
194 if (!scrypt_set_membuf(&ctx
->pass
, &ctx
->pass_len
, p
))
197 if ((p
= OSSL_PARAM_locate_const(params
, OSSL_KDF_PARAM_SALT
)) != NULL
)
198 if (!scrypt_set_membuf(&ctx
->salt
, &ctx
->salt_len
, p
))
201 if ((p
= OSSL_PARAM_locate_const(params
, OSSL_KDF_PARAM_SCRYPT_N
))
203 if (!OSSL_PARAM_get_uint64(p
, &u64_value
)
205 || !is_power_of_two(u64_value
))
210 if ((p
= OSSL_PARAM_locate_const(params
, OSSL_KDF_PARAM_SCRYPT_R
))
212 if (!OSSL_PARAM_get_uint64(p
, &u64_value
) || u64_value
< 1)
217 if ((p
= OSSL_PARAM_locate_const(params
, OSSL_KDF_PARAM_SCRYPT_P
))
219 if (!OSSL_PARAM_get_uint64(p
, &u64_value
) || u64_value
< 1)
224 if ((p
= OSSL_PARAM_locate_const(params
, OSSL_KDF_PARAM_SCRYPT_MAXMEM
))
226 if (!OSSL_PARAM_get_uint64(p
, &u64_value
) || u64_value
< 1)
228 ctx
->maxmem_bytes
= u64_value
;
231 p
= OSSL_PARAM_locate_const(params
, OSSL_KDF_PARAM_PROPERTIES
);
233 if (p
->data_type
!= OSSL_PARAM_UTF8_STRING
234 || !set_property_query(ctx
, p
->data
)
241 static const OSSL_PARAM
*kdf_scrypt_settable_ctx_params(ossl_unused
void *ctx
,
242 ossl_unused
void *p_ctx
)
244 static const OSSL_PARAM known_settable_ctx_params
[] = {
245 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD
, NULL
, 0),
246 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT
, NULL
, 0),
247 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N
, NULL
),
248 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R
, NULL
),
249 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P
, NULL
),
250 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM
, NULL
),
251 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES
, NULL
, 0),
254 return known_settable_ctx_params
;
257 static int kdf_scrypt_get_ctx_params(void *vctx
, OSSL_PARAM params
[])
261 if ((p
= OSSL_PARAM_locate(params
, OSSL_KDF_PARAM_SIZE
)) != NULL
)
262 return OSSL_PARAM_set_size_t(p
, SIZE_MAX
);
266 static const OSSL_PARAM
*kdf_scrypt_gettable_ctx_params(ossl_unused
void *ctx
,
267 ossl_unused
void *p_ctx
)
269 static const OSSL_PARAM known_gettable_ctx_params
[] = {
270 OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE
, NULL
),
273 return known_gettable_ctx_params
;
276 const OSSL_DISPATCH ossl_kdf_scrypt_functions
[] = {
277 { OSSL_FUNC_KDF_NEWCTX
, (void(*)(void))kdf_scrypt_new
},
278 { OSSL_FUNC_KDF_FREECTX
, (void(*)(void))kdf_scrypt_free
},
279 { OSSL_FUNC_KDF_RESET
, (void(*)(void))kdf_scrypt_reset
},
280 { OSSL_FUNC_KDF_DERIVE
, (void(*)(void))kdf_scrypt_derive
},
281 { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS
,
282 (void(*)(void))kdf_scrypt_settable_ctx_params
},
283 { OSSL_FUNC_KDF_SET_CTX_PARAMS
, (void(*)(void))kdf_scrypt_set_ctx_params
},
284 { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS
,
285 (void(*)(void))kdf_scrypt_gettable_ctx_params
},
286 { OSSL_FUNC_KDF_GET_CTX_PARAMS
, (void(*)(void))kdf_scrypt_get_ctx_params
},
290 #define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
291 static void salsa208_word_specification(uint32_t inout
[16])
296 memcpy(x
, inout
, sizeof(x
));
297 for (i
= 8; i
> 0; i
-= 2) {
298 x
[4] ^= R(x
[0] + x
[12], 7);
299 x
[8] ^= R(x
[4] + x
[0], 9);
300 x
[12] ^= R(x
[8] + x
[4], 13);
301 x
[0] ^= R(x
[12] + x
[8], 18);
302 x
[9] ^= R(x
[5] + x
[1], 7);
303 x
[13] ^= R(x
[9] + x
[5], 9);
304 x
[1] ^= R(x
[13] + x
[9], 13);
305 x
[5] ^= R(x
[1] + x
[13], 18);
306 x
[14] ^= R(x
[10] + x
[6], 7);
307 x
[2] ^= R(x
[14] + x
[10], 9);
308 x
[6] ^= R(x
[2] + x
[14], 13);
309 x
[10] ^= R(x
[6] + x
[2], 18);
310 x
[3] ^= R(x
[15] + x
[11], 7);
311 x
[7] ^= R(x
[3] + x
[15], 9);
312 x
[11] ^= R(x
[7] + x
[3], 13);
313 x
[15] ^= R(x
[11] + x
[7], 18);
314 x
[1] ^= R(x
[0] + x
[3], 7);
315 x
[2] ^= R(x
[1] + x
[0], 9);
316 x
[3] ^= R(x
[2] + x
[1], 13);
317 x
[0] ^= R(x
[3] + x
[2], 18);
318 x
[6] ^= R(x
[5] + x
[4], 7);
319 x
[7] ^= R(x
[6] + x
[5], 9);
320 x
[4] ^= R(x
[7] + x
[6], 13);
321 x
[5] ^= R(x
[4] + x
[7], 18);
322 x
[11] ^= R(x
[10] + x
[9], 7);
323 x
[8] ^= R(x
[11] + x
[10], 9);
324 x
[9] ^= R(x
[8] + x
[11], 13);
325 x
[10] ^= R(x
[9] + x
[8], 18);
326 x
[12] ^= R(x
[15] + x
[14], 7);
327 x
[13] ^= R(x
[12] + x
[15], 9);
328 x
[14] ^= R(x
[13] + x
[12], 13);
329 x
[15] ^= R(x
[14] + x
[13], 18);
331 for (i
= 0; i
< 16; ++i
)
333 OPENSSL_cleanse(x
, sizeof(x
));
336 static void scryptBlockMix(uint32_t *B_
, uint32_t *B
, uint64_t r
)
341 memcpy(X
, B
+ (r
* 2 - 1) * 16, sizeof(X
));
343 for (i
= 0; i
< r
* 2; i
++) {
344 for (j
= 0; j
< 16; j
++)
346 salsa208_word_specification(X
);
347 memcpy(B_
+ (i
/ 2 + (i
& 1) * r
) * 16, X
, sizeof(X
));
349 OPENSSL_cleanse(X
, sizeof(X
));
352 static void scryptROMix(unsigned char *B
, uint64_t r
, uint64_t N
,
353 uint32_t *X
, uint32_t *T
, uint32_t *V
)
359 /* Convert from little endian input */
360 for (pV
= V
, i
= 0, pB
= B
; i
< 32 * r
; i
++, pV
++) {
364 *pV
|= (uint32_t)*pB
++ << 24;
367 for (i
= 1; i
< N
; i
++, pV
+= 32 * r
)
368 scryptBlockMix(pV
, pV
- 32 * r
, r
);
370 scryptBlockMix(X
, V
+ (N
- 1) * 32 * r
, r
);
372 for (i
= 0; i
< N
; i
++) {
374 j
= X
[16 * (2 * r
- 1)] % N
;
376 for (k
= 0; k
< 32 * r
; k
++)
378 scryptBlockMix(X
, T
, r
);
380 /* Convert output to little endian */
381 for (i
= 0, pB
= B
; i
< 32 * r
; i
++) {
382 uint32_t xtmp
= X
[i
];
384 *pB
++ = (xtmp
>> 8) & 0xff;
385 *pB
++ = (xtmp
>> 16) & 0xff;
386 *pB
++ = (xtmp
>> 24) & 0xff;
391 # define SIZE_MAX ((size_t)-1)
395 * Maximum power of two that will fit in uint64_t: this should work on
396 * most (all?) platforms.
399 #define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1)
402 * Maximum value of p * r:
403 * p <= ((2^32-1) * hLen) / MFLen =>
404 * p <= ((2^32-1) * 32) / (128 * r) =>
408 #define SCRYPT_PR_MAX ((1 << 30) - 1)
410 static int scrypt_alg(const char *pass
, size_t passlen
,
411 const unsigned char *salt
, size_t saltlen
,
412 uint64_t N
, uint64_t r
, uint64_t p
, uint64_t maxmem
,
413 unsigned char *key
, size_t keylen
, EVP_MD
*sha256
,
414 OSSL_LIB_CTX
*libctx
, const char *propq
)
419 uint64_t i
, Blen
, Vlen
;
421 /* Sanity check parameters */
422 /* initial check, r,p must be non zero, N >= 2 and a power of 2 */
423 if (r
== 0 || p
== 0 || N
< 2 || (N
& (N
- 1)))
425 /* Check p * r < SCRYPT_PR_MAX avoiding overflow */
426 if (p
> SCRYPT_PR_MAX
/ r
) {
427 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
432 * Need to check N: if 2^(128 * r / 8) overflows limit this is
433 * automatically satisfied since N <= UINT64_MAX.
436 if (16 * r
<= LOG2_UINT64_MAX
) {
437 if (N
>= (((uint64_t)1) << (16 * r
))) {
438 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
443 /* Memory checks: check total allocated buffer size fits in uint64_t */
446 * B size in section 5 step 1.S
447 * Note: we know p * 128 * r < UINT64_MAX because we already checked
448 * p * r < SCRYPT_PR_MAX
452 * Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
453 * have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
455 if (Blen
> INT_MAX
) {
456 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
461 * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
462 * This is combined size V, X and T (section 4)
464 i
= UINT64_MAX
/ (32 * sizeof(uint32_t));
466 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
469 Vlen
= 32 * r
* (N
+ 2) * sizeof(uint32_t);
471 /* check total allocated size fits in uint64_t */
472 if (Blen
> UINT64_MAX
- Vlen
) {
473 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
477 /* Check that the maximum memory doesn't exceed a size_t limits */
478 if (maxmem
> SIZE_MAX
)
481 if (Blen
+ Vlen
> maxmem
) {
482 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
486 /* If no key return to indicate parameters are OK */
490 B
= OPENSSL_malloc((size_t)(Blen
+ Vlen
));
492 ERR_raise(ERR_LIB_EVP
, ERR_R_MALLOC_FAILURE
);
495 X
= (uint32_t *)(B
+ Blen
);
498 if (ossl_pkcs5_pbkdf2_hmac_ex(pass
, passlen
, salt
, saltlen
, 1, sha256
,
499 (int)Blen
, B
, libctx
, propq
) == 0)
502 for (i
= 0; i
< p
; i
++)
503 scryptROMix(B
+ 128 * r
* i
, r
, N
, X
, T
, V
);
505 if (ossl_pkcs5_pbkdf2_hmac_ex(pass
, passlen
, B
, (int)Blen
, 1, sha256
,
506 keylen
, key
, libctx
, propq
) == 0)
511 ERR_raise(ERR_LIB_EVP
, EVP_R_PBKDF2_ERROR
);
513 OPENSSL_clear_free(B
, (size_t)(Blen
+ Vlen
));