1 | /* |
2 | * Copyright 2015-2018 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 <openssl/evp.h> |
11 | #include <openssl/err.h> |
12 | #include <openssl/kdf.h> |
13 | #include <openssl/core_names.h> |
14 | #include "internal/numbers.h" |
15 | |
16 | #ifndef OPENSSL_NO_SCRYPT |
17 | |
18 | /* |
19 | * Maximum permitted memory allow this to be overridden with Configuration |
20 | * option: e.g. -DSCRYPT_MAX_MEM=0 for maximum possible. |
21 | */ |
22 | |
23 | #ifdef SCRYPT_MAX_MEM |
24 | # if SCRYPT_MAX_MEM == 0 |
25 | # undef SCRYPT_MAX_MEM |
26 | /* |
27 | * Although we could theoretically allocate SIZE_MAX memory that would leave |
28 | * no memory available for anything else so set limit as half that. |
29 | */ |
30 | # define SCRYPT_MAX_MEM (SIZE_MAX/2) |
31 | # endif |
32 | #else |
33 | /* Default memory limit: 32 MB */ |
34 | # define SCRYPT_MAX_MEM (1024 * 1024 * 32) |
35 | #endif |
36 | |
37 | int EVP_PBE_scrypt(const char *pass, size_t passlen, |
38 | const unsigned char *salt, size_t saltlen, |
39 | uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem, |
40 | unsigned char *key, size_t keylen) |
41 | { |
42 | const char *empty = "" ; |
43 | int rv = 1; |
44 | EVP_KDF *kdf; |
45 | EVP_KDF_CTX *kctx; |
46 | OSSL_PARAM params[7], *z = params; |
47 | |
48 | if (r > UINT32_MAX || p > UINT32_MAX) { |
49 | EVPerr(EVP_F_EVP_PBE_SCRYPT, EVP_R_PARAMETER_TOO_LARGE); |
50 | return 0; |
51 | } |
52 | |
53 | /* Maintain existing behaviour. */ |
54 | if (pass == NULL) { |
55 | pass = empty; |
56 | passlen = 0; |
57 | } |
58 | if (salt == NULL) { |
59 | salt = (const unsigned char *)empty; |
60 | saltlen = 0; |
61 | } |
62 | if (maxmem == 0) |
63 | maxmem = SCRYPT_MAX_MEM; |
64 | |
65 | kdf = EVP_KDF_fetch(NULL, OSSL_KDF_NAME_SCRYPT, NULL); |
66 | kctx = EVP_KDF_CTX_new(kdf); |
67 | EVP_KDF_free(kdf); |
68 | if (kctx == NULL) |
69 | return 0; |
70 | |
71 | *z++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PASSWORD, |
72 | (unsigned char *)pass, |
73 | passlen); |
74 | *z++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, |
75 | (unsigned char *)salt, saltlen); |
76 | *z++ = OSSL_PARAM_construct_uint64(OSSL_KDF_PARAM_SCRYPT_N, &N); |
77 | *z++ = OSSL_PARAM_construct_uint64(OSSL_KDF_PARAM_SCRYPT_R, &r); |
78 | *z++ = OSSL_PARAM_construct_uint64(OSSL_KDF_PARAM_SCRYPT_P, &p); |
79 | *z++ = OSSL_PARAM_construct_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, &maxmem); |
80 | *z = OSSL_PARAM_construct_end(); |
81 | if (EVP_KDF_CTX_set_params(kctx, params) != 1 |
82 | || EVP_KDF_derive(kctx, key, keylen) != 1) |
83 | rv = 0; |
84 | |
85 | EVP_KDF_CTX_free(kctx); |
86 | return rv; |
87 | } |
88 | |
89 | #endif |
90 | |