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
);
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
, size_t keylen
,
151 const OSSL_PARAM params
[])
153 KDF_SCRYPT
*ctx
= (KDF_SCRYPT
*)vctx
;
155 if (!ossl_prov_is_running() || !kdf_scrypt_set_ctx_params(ctx
, params
))
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 *ctx
,
237 ossl_unused
void *p_ctx
)
239 static const OSSL_PARAM known_settable_ctx_params
[] = {
240 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD
, NULL
, 0),
241 OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT
, NULL
, 0),
242 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N
, NULL
),
243 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R
, NULL
),
244 OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P
, NULL
),
245 OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM
, NULL
),
246 OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES
, NULL
, 0),
249 return known_settable_ctx_params
;
252 static int kdf_scrypt_get_ctx_params(void *vctx
, OSSL_PARAM params
[])
256 if ((p
= OSSL_PARAM_locate(params
, OSSL_KDF_PARAM_SIZE
)) != NULL
)
257 return OSSL_PARAM_set_size_t(p
, SIZE_MAX
);
261 static const OSSL_PARAM
*kdf_scrypt_gettable_ctx_params(ossl_unused
void *ctx
,
262 ossl_unused
void *p_ctx
)
264 static const OSSL_PARAM known_gettable_ctx_params
[] = {
265 OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE
, NULL
),
268 return known_gettable_ctx_params
;
271 const OSSL_DISPATCH ossl_kdf_scrypt_functions
[] = {
272 { OSSL_FUNC_KDF_NEWCTX
, (void(*)(void))kdf_scrypt_new
},
273 { OSSL_FUNC_KDF_FREECTX
, (void(*)(void))kdf_scrypt_free
},
274 { OSSL_FUNC_KDF_RESET
, (void(*)(void))kdf_scrypt_reset
},
275 { OSSL_FUNC_KDF_DERIVE
, (void(*)(void))kdf_scrypt_derive
},
276 { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS
,
277 (void(*)(void))kdf_scrypt_settable_ctx_params
},
278 { OSSL_FUNC_KDF_SET_CTX_PARAMS
, (void(*)(void))kdf_scrypt_set_ctx_params
},
279 { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS
,
280 (void(*)(void))kdf_scrypt_gettable_ctx_params
},
281 { OSSL_FUNC_KDF_GET_CTX_PARAMS
, (void(*)(void))kdf_scrypt_get_ctx_params
},
285 #define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
286 static void salsa208_word_specification(uint32_t inout
[16])
291 memcpy(x
, inout
, sizeof(x
));
292 for (i
= 8; i
> 0; i
-= 2) {
293 x
[4] ^= R(x
[0] + x
[12], 7);
294 x
[8] ^= R(x
[4] + x
[0], 9);
295 x
[12] ^= R(x
[8] + x
[4], 13);
296 x
[0] ^= R(x
[12] + x
[8], 18);
297 x
[9] ^= R(x
[5] + x
[1], 7);
298 x
[13] ^= R(x
[9] + x
[5], 9);
299 x
[1] ^= R(x
[13] + x
[9], 13);
300 x
[5] ^= R(x
[1] + x
[13], 18);
301 x
[14] ^= R(x
[10] + x
[6], 7);
302 x
[2] ^= R(x
[14] + x
[10], 9);
303 x
[6] ^= R(x
[2] + x
[14], 13);
304 x
[10] ^= R(x
[6] + x
[2], 18);
305 x
[3] ^= R(x
[15] + x
[11], 7);
306 x
[7] ^= R(x
[3] + x
[15], 9);
307 x
[11] ^= R(x
[7] + x
[3], 13);
308 x
[15] ^= R(x
[11] + x
[7], 18);
309 x
[1] ^= R(x
[0] + x
[3], 7);
310 x
[2] ^= R(x
[1] + x
[0], 9);
311 x
[3] ^= R(x
[2] + x
[1], 13);
312 x
[0] ^= R(x
[3] + x
[2], 18);
313 x
[6] ^= R(x
[5] + x
[4], 7);
314 x
[7] ^= R(x
[6] + x
[5], 9);
315 x
[4] ^= R(x
[7] + x
[6], 13);
316 x
[5] ^= R(x
[4] + x
[7], 18);
317 x
[11] ^= R(x
[10] + x
[9], 7);
318 x
[8] ^= R(x
[11] + x
[10], 9);
319 x
[9] ^= R(x
[8] + x
[11], 13);
320 x
[10] ^= R(x
[9] + x
[8], 18);
321 x
[12] ^= R(x
[15] + x
[14], 7);
322 x
[13] ^= R(x
[12] + x
[15], 9);
323 x
[14] ^= R(x
[13] + x
[12], 13);
324 x
[15] ^= R(x
[14] + x
[13], 18);
326 for (i
= 0; i
< 16; ++i
)
328 OPENSSL_cleanse(x
, sizeof(x
));
331 static void scryptBlockMix(uint32_t *B_
, uint32_t *B
, uint64_t r
)
336 memcpy(X
, B
+ (r
* 2 - 1) * 16, sizeof(X
));
338 for (i
= 0; i
< r
* 2; i
++) {
339 for (j
= 0; j
< 16; j
++)
341 salsa208_word_specification(X
);
342 memcpy(B_
+ (i
/ 2 + (i
& 1) * r
) * 16, X
, sizeof(X
));
344 OPENSSL_cleanse(X
, sizeof(X
));
347 static void scryptROMix(unsigned char *B
, uint64_t r
, uint64_t N
,
348 uint32_t *X
, uint32_t *T
, uint32_t *V
)
354 /* Convert from little endian input */
355 for (pV
= V
, i
= 0, pB
= B
; i
< 32 * r
; i
++, pV
++) {
359 *pV
|= (uint32_t)*pB
++ << 24;
362 for (i
= 1; i
< N
; i
++, pV
+= 32 * r
)
363 scryptBlockMix(pV
, pV
- 32 * r
, r
);
365 scryptBlockMix(X
, V
+ (N
- 1) * 32 * r
, r
);
367 for (i
= 0; i
< N
; i
++) {
369 j
= X
[16 * (2 * r
- 1)] % N
;
371 for (k
= 0; k
< 32 * r
; k
++)
373 scryptBlockMix(X
, T
, r
);
375 /* Convert output to little endian */
376 for (i
= 0, pB
= B
; i
< 32 * r
; i
++) {
377 uint32_t xtmp
= X
[i
];
379 *pB
++ = (xtmp
>> 8) & 0xff;
380 *pB
++ = (xtmp
>> 16) & 0xff;
381 *pB
++ = (xtmp
>> 24) & 0xff;
386 # define SIZE_MAX ((size_t)-1)
390 * Maximum power of two that will fit in uint64_t: this should work on
391 * most (all?) platforms.
394 #define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1)
397 * Maximum value of p * r:
398 * p <= ((2^32-1) * hLen) / MFLen =>
399 * p <= ((2^32-1) * 32) / (128 * r) =>
403 #define SCRYPT_PR_MAX ((1 << 30) - 1)
405 static int scrypt_alg(const char *pass
, size_t passlen
,
406 const unsigned char *salt
, size_t saltlen
,
407 uint64_t N
, uint64_t r
, uint64_t p
, uint64_t maxmem
,
408 unsigned char *key
, size_t keylen
, EVP_MD
*sha256
,
409 OSSL_LIB_CTX
*libctx
, const char *propq
)
414 uint64_t i
, Blen
, Vlen
;
416 /* Sanity check parameters */
417 /* initial check, r,p must be non zero, N >= 2 and a power of 2 */
418 if (r
== 0 || p
== 0 || N
< 2 || (N
& (N
- 1)))
420 /* Check p * r < SCRYPT_PR_MAX avoiding overflow */
421 if (p
> SCRYPT_PR_MAX
/ r
) {
422 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
427 * Need to check N: if 2^(128 * r / 8) overflows limit this is
428 * automatically satisfied since N <= UINT64_MAX.
431 if (16 * r
<= LOG2_UINT64_MAX
) {
432 if (N
>= (((uint64_t)1) << (16 * r
))) {
433 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
438 /* Memory checks: check total allocated buffer size fits in uint64_t */
441 * B size in section 5 step 1.S
442 * Note: we know p * 128 * r < UINT64_MAX because we already checked
443 * p * r < SCRYPT_PR_MAX
447 * Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
448 * have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
450 if (Blen
> INT_MAX
) {
451 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
456 * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
457 * This is combined size V, X and T (section 4)
459 i
= UINT64_MAX
/ (32 * sizeof(uint32_t));
461 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
464 Vlen
= 32 * r
* (N
+ 2) * sizeof(uint32_t);
466 /* check total allocated size fits in uint64_t */
467 if (Blen
> UINT64_MAX
- Vlen
) {
468 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
472 /* Check that the maximum memory doesn't exceed a size_t limits */
473 if (maxmem
> SIZE_MAX
)
476 if (Blen
+ Vlen
> maxmem
) {
477 ERR_raise(ERR_LIB_EVP
, EVP_R_MEMORY_LIMIT_EXCEEDED
);
481 /* If no key return to indicate parameters are OK */
485 B
= OPENSSL_malloc((size_t)(Blen
+ Vlen
));
487 ERR_raise(ERR_LIB_EVP
, ERR_R_MALLOC_FAILURE
);
490 X
= (uint32_t *)(B
+ Blen
);
493 if (pkcs5_pbkdf2_hmac_ex(pass
, passlen
, salt
, saltlen
, 1, sha256
, (int)Blen
,
494 B
, libctx
, propq
) == 0)
497 for (i
= 0; i
< p
; i
++)
498 scryptROMix(B
+ 128 * r
* i
, r
, N
, X
, T
, V
);
500 if (pkcs5_pbkdf2_hmac_ex(pass
, passlen
, B
, (int)Blen
, 1, sha256
, keylen
,
501 key
, libctx
, propq
) == 0)
506 ERR_raise(ERR_LIB_EVP
, EVP_R_PBKDF2_ERROR
);
508 OPENSSL_clear_free(B
, (size_t)(Blen
+ Vlen
));