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/rfc5869 20 */ 21 22 static unsigned char hkdf_salt[] = { 23 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 24 0x0c 25 }; 26 27 static unsigned char hkdf_ikm[] = { 28 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 29 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b 30 }; 31 32 static unsigned char hkdf_info[] = { 33 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9 34 }; 35 36 /* Expected output keying material */ 37 static unsigned char hkdf_okm[] = { 38 0x3c, 0xb2, 0x5f, 0x25, 0xfa, 0xac, 0xd5, 0x7a, 0x90, 0x43, 0x4f, 0x64, 39 0xd0, 0x36, 0x2f, 0x2a, 0x2d, 0x2d, 0x0a, 0x90, 0xcf, 0x1a, 0x5a, 0x4c, 40 0x5d, 0xb0, 0x2d, 0x56, 0xec, 0xc4, 0xc5, 0xbf, 0x34, 0x00, 0x72, 0x08, 41 0xd5, 0xb8, 0x87, 0x18, 0x58, 0x65 42 }; 43 44 int main(int argc, char **argv) 45 { 46 int rv = 1; 47 EVP_KDF *kdf = NULL; 48 EVP_KDF_CTX *kctx = NULL; 49 unsigned char out[42]; 50 OSSL_PARAM params[5], *p = params; 51 OSSL_LIB_CTX *library_context = NULL; 52 53 library_context = OSSL_LIB_CTX_new(); 54 if (library_context == NULL) { 55 fprintf(stderr, "OSSL_LIB_CTX_new() returned NULL\n"); 56 goto end; 57 } 58 59 /* Fetch the key derivation function implementation */ 60 kdf = EVP_KDF_fetch(library_context, "HKDF", NULL); 61 if (kdf == NULL) { 62 fprintf(stderr, "EVP_KDF_fetch() returned NULL\n"); 63 goto end; 64 } 65 66 /* Create a context for the key derivation operation */ 67 kctx = EVP_KDF_CTX_new(kdf); 68 if (kctx == NULL) { 69 fprintf(stderr, "EVP_KDF_CTX_new() returned NULL\n"); 70 goto end; 71 } 72 73 /* Set the underlying hash function used to derive the key */ 74 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, 75 "SHA256", 0); 76 /* Set input keying material */ 77 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, hkdf_ikm, 78 sizeof(hkdf_ikm)); 79 /* Set application specific information */ 80 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_INFO, hkdf_info, 81 sizeof(hkdf_info)); 82 /* Set salt */ 83 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, hkdf_salt, 84 sizeof(hkdf_salt)); 85 *p = OSSL_PARAM_construct_end(); 86 87 /* Derive the key */ 88 if (EVP_KDF_derive(kctx, out, sizeof(out), params) != 1) { 89 fprintf(stderr, "EVP_KDF_derive() failed\n"); 90 goto end; 91 } 92 93 if (CRYPTO_memcmp(hkdf_okm, out, sizeof(hkdf_okm)) != 0) { 94 fprintf(stderr, "Generated key does not match expected value\n"); 95 goto end; 96 } 97 98 rv = 0; 99 end: 100 EVP_KDF_CTX_free(kctx); 101 EVP_KDF_free(kdf); 102 OSSL_LIB_CTX_free(library_context); 103 return rv; 104 } 105