1 /* 2 * Copyright 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 <stdio.h> 11 #include <openssl/core_names.h> 12 #include <openssl/crypto.h> 13 #include <openssl/kdf.h> 14 #include <openssl/obj_mac.h> 15 #include <openssl/params.h> 16 17 /* 18 * test vector from 19 * https://datatracker.ietf.org/doc/html/rfc7914 20 */ 21 22 /* 23 * Hard coding a password into an application is very bad. 24 * It is done here solely for educational purposes. 25 */ 26 static unsigned char password[] = { 27 'P', 'a', 's', 's', 'w', 'o', 'r', 'd' 28 }; 29 30 /* 31 * The salt is better not being hard coded too. Each password should have a 32 * different salt if possible. The salt is not considered secret information 33 * and is safe to store with an encrypted password. 34 */ 35 static unsigned char pbkdf2_salt[] = { 36 'N', 'a', 'C', 'l' 37 }; 38 39 /* 40 * The iteration parameter can be variable or hard coded. The disadvantage with 41 * hard coding them is that they cannot easily be adjusted for future 42 * technological improvements appear. 43 */ 44 static unsigned int pbkdf2_iterations = 80000; 45 46 static const unsigned char expected_output[] = { 47 48 0x4d, 0xdc, 0xd8, 0xf6, 0x0b, 0x98, 0xbe, 0x21, 49 0x83, 0x0c, 0xee, 0x5e, 0xf2, 0x27, 0x01, 0xf9, 50 0x64, 0x1a, 0x44, 0x18, 0xd0, 0x4c, 0x04, 0x14, 51 0xae, 0xff, 0x08, 0x87, 0x6b, 0x34, 0xab, 0x56, 52 0xa1, 0xd4, 0x25, 0xa1, 0x22, 0x58, 0x33, 0x54, 53 0x9a, 0xdb, 0x84, 0x1b, 0x51, 0xc9, 0xb3, 0x17, 54 0x6a, 0x27, 0x2b, 0xde, 0xbb, 0xa1, 0xd0, 0x78, 55 0x47, 0x8f, 0x62, 0xb3, 0x97, 0xf3, 0x3c, 0x8d 56 }; 57 58 int main(int argc, char **argv) 59 { 60 int rv = 1; 61 EVP_KDF *kdf = NULL; 62 EVP_KDF_CTX *kctx = NULL; 63 unsigned char out[64]; 64 OSSL_PARAM params[5], *p = params; 65 OSSL_LIB_CTX *library_context = NULL; 66 67 library_context = OSSL_LIB_CTX_new(); 68 if (library_context == NULL) { 69 fprintf(stderr, "OSSL_LIB_CTX_new() returned NULL\n"); 70 goto end; 71 } 72 73 /* Fetch the key derivation function implementation */ 74 kdf = EVP_KDF_fetch(library_context, "PBKDF2", NULL); 75 if (kdf == NULL) { 76 fprintf(stderr, "EVP_KDF_fetch() returned NULL\n"); 77 goto end; 78 } 79 80 /* Create a context for the key derivation operation */ 81 kctx = EVP_KDF_CTX_new(kdf); 82 if (kctx == NULL) { 83 fprintf(stderr, "EVP_KDF_CTX_new() returned NULL\n"); 84 goto end; 85 } 86 87 /* Set password */ 88 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PASSWORD, password, 89 sizeof(password)); 90 /* Set salt */ 91 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, pbkdf2_salt, 92 sizeof(pbkdf2_salt)); 93 /* Set iteration count (default 2048) */ 94 *p++ = OSSL_PARAM_construct_uint(OSSL_KDF_PARAM_ITER, &pbkdf2_iterations); 95 /* Set the underlying hash function used to derive the key */ 96 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, 97 "SHA256", 0); 98 *p = OSSL_PARAM_construct_end(); 99 100 /* Derive the key */ 101 if (EVP_KDF_derive(kctx, out, sizeof(out), params) != 1) { 102 fprintf(stderr, "EVP_KDF_derive() failed\n"); 103 goto end; 104 } 105 106 if (CRYPTO_memcmp(expected_output, out, sizeof(expected_output)) != 0) { 107 fprintf(stderr, "Generated key does not match expected value\n"); 108 goto end; 109 } 110 111 rv = 0; 112 end: 113 EVP_KDF_CTX_free(kctx); 114 EVP_KDF_free(kdf); 115 OSSL_LIB_CTX_free(library_context); 116 return rv; 117 } 118