1 /*
2 * Copyright 2017-2021 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
kdf_scrypt_new(void * provctx)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
kdf_scrypt_free(void * vctx)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
kdf_scrypt_reset(void * vctx)86 static void kdf_scrypt_reset(void *vctx)
87 {
88 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
89
90 OPENSSL_free(ctx->salt);
91 OPENSSL_clear_free(ctx->pass, ctx->pass_len);
92 kdf_scrypt_init(ctx);
93 }
94
kdf_scrypt_init(KDF_SCRYPT * ctx)95 static void kdf_scrypt_init(KDF_SCRYPT *ctx)
96 {
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).
100 */
101 ctx->N = 1 << 20;
102 ctx->r = 8;
103 ctx->p = 1;
104 ctx->maxmem_bytes = 1025 * 1024 * 1024;
105 }
106
scrypt_set_membuf(unsigned char ** buffer,size_t * buflen,const OSSL_PARAM * p)107 static int scrypt_set_membuf(unsigned char **buffer, size_t *buflen,
108 const OSSL_PARAM *p)
109 {
110 OPENSSL_clear_free(*buffer, *buflen);
111 *buffer = NULL;
112 *buflen = 0;
113
114 if (p->data_size == 0) {
115 if ((*buffer = OPENSSL_malloc(1)) == NULL) {
116 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
117 return 0;
118 }
119 } else if (p->data != NULL) {
120 if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
121 return 0;
122 }
123 return 1;
124 }
125
set_digest(KDF_SCRYPT * ctx)126 static int set_digest(KDF_SCRYPT *ctx)
127 {
128 EVP_MD_free(ctx->sha256);
129 ctx->sha256 = EVP_MD_fetch(ctx->libctx, "sha256", ctx->propq);
130 if (ctx->sha256 == NULL) {
131 OPENSSL_free(ctx);
132 ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256);
133 return 0;
134 }
135 return 1;
136 }
137
set_property_query(KDF_SCRYPT * ctx,const char * propq)138 static int set_property_query(KDF_SCRYPT *ctx, const char *propq)
139 {
140 OPENSSL_free(ctx->propq);
141 ctx->propq = NULL;
142 if (propq != NULL) {
143 ctx->propq = OPENSSL_strdup(propq);
144 if (ctx->propq == NULL) {
145 ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
146 return 0;
147 }
148 }
149 return 1;
150 }
151
kdf_scrypt_derive(void * vctx,unsigned char * key,size_t keylen,const OSSL_PARAM params[])152 static int kdf_scrypt_derive(void *vctx, unsigned char *key, size_t keylen,
153 const OSSL_PARAM params[])
154 {
155 KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
156
157 if (!ossl_prov_is_running() || !kdf_scrypt_set_ctx_params(ctx, params))
158 return 0;
159
160 if (ctx->pass == NULL) {
161 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
162 return 0;
163 }
164
165 if (ctx->salt == NULL) {
166 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
167 return 0;
168 }
169
170 if (ctx->sha256 == NULL && !set_digest(ctx))
171 return 0;
172
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);
177 }
178
is_power_of_two(uint64_t value)179 static int is_power_of_two(uint64_t value)
180 {
181 return (value != 0) && ((value & (value - 1)) == 0);
182 }
183
kdf_scrypt_set_ctx_params(void * vctx,const OSSL_PARAM params[])184 static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[])
185 {
186 const OSSL_PARAM *p;
187 KDF_SCRYPT *ctx = vctx;
188 uint64_t u64_value;
189
190 if (params == NULL)
191 return 1;
192
193 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
194 if (!scrypt_set_membuf(&ctx->pass, &ctx->pass_len, p))
195 return 0;
196
197 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL)
198 if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p))
199 return 0;
200
201 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N))
202 != NULL) {
203 if (!OSSL_PARAM_get_uint64(p, &u64_value)
204 || u64_value <= 1
205 || !is_power_of_two(u64_value))
206 return 0;
207 ctx->N = u64_value;
208 }
209
210 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R))
211 != NULL) {
212 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
213 return 0;
214 ctx->r = u64_value;
215 }
216
217 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P))
218 != NULL) {
219 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
220 return 0;
221 ctx->p = u64_value;
222 }
223
224 if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM))
225 != NULL) {
226 if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
227 return 0;
228 ctx->maxmem_bytes = u64_value;
229 }
230
231 p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PROPERTIES);
232 if (p != NULL) {
233 if (p->data_type != OSSL_PARAM_UTF8_STRING
234 || !set_property_query(ctx, p->data)
235 || !set_digest(ctx))
236 return 0;
237 }
238 return 1;
239 }
240
kdf_scrypt_settable_ctx_params(ossl_unused void * ctx,ossl_unused void * p_ctx)241 static const OSSL_PARAM *kdf_scrypt_settable_ctx_params(ossl_unused void *ctx,
242 ossl_unused void *p_ctx)
243 {
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),
252 OSSL_PARAM_END
253 };
254 return known_settable_ctx_params;
255 }
256
kdf_scrypt_get_ctx_params(void * vctx,OSSL_PARAM params[])257 static int kdf_scrypt_get_ctx_params(void *vctx, OSSL_PARAM params[])
258 {
259 OSSL_PARAM *p;
260
261 if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
262 return OSSL_PARAM_set_size_t(p, SIZE_MAX);
263 return -2;
264 }
265
kdf_scrypt_gettable_ctx_params(ossl_unused void * ctx,ossl_unused void * p_ctx)266 static const OSSL_PARAM *kdf_scrypt_gettable_ctx_params(ossl_unused void *ctx,
267 ossl_unused void *p_ctx)
268 {
269 static const OSSL_PARAM known_gettable_ctx_params[] = {
270 OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
271 OSSL_PARAM_END
272 };
273 return known_gettable_ctx_params;
274 }
275
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 },
287 { 0, NULL }
288 };
289
290 #define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
salsa208_word_specification(uint32_t inout[16])291 static void salsa208_word_specification(uint32_t inout[16])
292 {
293 int i;
294 uint32_t x[16];
295
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);
330 }
331 for (i = 0; i < 16; ++i)
332 inout[i] += x[i];
333 OPENSSL_cleanse(x, sizeof(x));
334 }
335
scryptBlockMix(uint32_t * B_,uint32_t * B,uint64_t r)336 static void scryptBlockMix(uint32_t *B_, uint32_t *B, uint64_t r)
337 {
338 uint64_t i, j;
339 uint32_t X[16], *pB;
340
341 memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
342 pB = B;
343 for (i = 0; i < r * 2; i++) {
344 for (j = 0; j < 16; j++)
345 X[j] ^= *pB++;
346 salsa208_word_specification(X);
347 memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
348 }
349 OPENSSL_cleanse(X, sizeof(X));
350 }
351
scryptROMix(unsigned char * B,uint64_t r,uint64_t N,uint32_t * X,uint32_t * T,uint32_t * V)352 static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
353 uint32_t *X, uint32_t *T, uint32_t *V)
354 {
355 unsigned char *pB;
356 uint32_t *pV;
357 uint64_t i, k;
358
359 /* Convert from little endian input */
360 for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
361 *pV = *pB++;
362 *pV |= *pB++ << 8;
363 *pV |= *pB++ << 16;
364 *pV |= (uint32_t)*pB++ << 24;
365 }
366
367 for (i = 1; i < N; i++, pV += 32 * r)
368 scryptBlockMix(pV, pV - 32 * r, r);
369
370 scryptBlockMix(X, V + (N - 1) * 32 * r, r);
371
372 for (i = 0; i < N; i++) {
373 uint32_t j;
374 j = X[16 * (2 * r - 1)] % N;
375 pV = V + 32 * r * j;
376 for (k = 0; k < 32 * r; k++)
377 T[k] = X[k] ^ *pV++;
378 scryptBlockMix(X, T, r);
379 }
380 /* Convert output to little endian */
381 for (i = 0, pB = B; i < 32 * r; i++) {
382 uint32_t xtmp = X[i];
383 *pB++ = xtmp & 0xff;
384 *pB++ = (xtmp >> 8) & 0xff;
385 *pB++ = (xtmp >> 16) & 0xff;
386 *pB++ = (xtmp >> 24) & 0xff;
387 }
388 }
389
390 #ifndef SIZE_MAX
391 # define SIZE_MAX ((size_t)-1)
392 #endif
393
394 /*
395 * Maximum power of two that will fit in uint64_t: this should work on
396 * most (all?) platforms.
397 */
398
399 #define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1)
400
401 /*
402 * Maximum value of p * r:
403 * p <= ((2^32-1) * hLen) / MFLen =>
404 * p <= ((2^32-1) * 32) / (128 * r) =>
405 * p * r <= (2^30-1)
406 */
407
408 #define SCRYPT_PR_MAX ((1 << 30) - 1)
409
scrypt_alg(const char * pass,size_t passlen,const unsigned char * salt,size_t saltlen,uint64_t N,uint64_t r,uint64_t p,uint64_t maxmem,unsigned char * key,size_t keylen,EVP_MD * sha256,OSSL_LIB_CTX * libctx,const char * propq)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)
415 {
416 int rv = 0;
417 unsigned char *B;
418 uint32_t *X, *V, *T;
419 uint64_t i, Blen, Vlen;
420
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)))
424 return 0;
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);
428 return 0;
429 }
430
431 /*
432 * Need to check N: if 2^(128 * r / 8) overflows limit this is
433 * automatically satisfied since N <= UINT64_MAX.
434 */
435
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);
439 return 0;
440 }
441 }
442
443 /* Memory checks: check total allocated buffer size fits in uint64_t */
444
445 /*
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
449 */
450 Blen = p * 128 * r;
451 /*
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.]
454 */
455 if (Blen > INT_MAX) {
456 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
457 return 0;
458 }
459
460 /*
461 * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
462 * This is combined size V, X and T (section 4)
463 */
464 i = UINT64_MAX / (32 * sizeof(uint32_t));
465 if (N + 2 > i / r) {
466 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
467 return 0;
468 }
469 Vlen = 32 * r * (N + 2) * sizeof(uint32_t);
470
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);
474 return 0;
475 }
476
477 /* Check that the maximum memory doesn't exceed a size_t limits */
478 if (maxmem > SIZE_MAX)
479 maxmem = SIZE_MAX;
480
481 if (Blen + Vlen > maxmem) {
482 ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
483 return 0;
484 }
485
486 /* If no key return to indicate parameters are OK */
487 if (key == NULL)
488 return 1;
489
490 B = OPENSSL_malloc((size_t)(Blen + Vlen));
491 if (B == NULL) {
492 ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
493 return 0;
494 }
495 X = (uint32_t *)(B + Blen);
496 T = X + 32 * r;
497 V = T + 32 * r;
498 if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, 1, sha256,
499 (int)Blen, B, libctx, propq) == 0)
500 goto err;
501
502 for (i = 0; i < p; i++)
503 scryptROMix(B + 128 * r * i, r, N, X, T, V);
504
505 if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, B, (int)Blen, 1, sha256,
506 keylen, key, libctx, propq) == 0)
507 goto err;
508 rv = 1;
509 err:
510 if (rv == 0)
511 ERR_raise(ERR_LIB_EVP, EVP_R_PBKDF2_ERROR);
512
513 OPENSSL_clear_free(B, (size_t)(Blen + Vlen));
514 return rv;
515 }
516
517 #endif
518