1 /* 2 * Copyright 2015-2021 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 /* 11 * ECDH low level APIs are deprecated for public use, but still ok for 12 * internal use. 13 */ 14 #include "internal/deprecated.h" 15 16 #include <string.h> 17 #include <openssl/core_names.h> 18 #include <openssl/ec.h> 19 #include <openssl/evp.h> 20 #include <openssl/kdf.h> 21 #include "ec_local.h" 22 23 /* Key derivation function from X9.63/SECG */ 24 int ossl_ecdh_kdf_X9_63(unsigned char *out, size_t outlen, 25 const unsigned char *Z, size_t Zlen, 26 const unsigned char *sinfo, size_t sinfolen, 27 const EVP_MD *md, 28 OSSL_LIB_CTX *libctx, const char *propq) 29 { 30 int ret = 0; 31 EVP_KDF_CTX *kctx = NULL; 32 OSSL_PARAM params[4], *p = params; 33 const char *mdname = EVP_MD_get0_name(md); 34 EVP_KDF *kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_X963KDF, propq); 35 36 if ((kctx = EVP_KDF_CTX_new(kdf)) != NULL) { 37 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, 38 (char *)mdname, 0); 39 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, 40 (void *)Z, Zlen); 41 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_INFO, 42 (void *)sinfo, sinfolen); 43 *p = OSSL_PARAM_construct_end(); 44 45 ret = EVP_KDF_derive(kctx, out, outlen, params) > 0; 46 EVP_KDF_CTX_free(kctx); 47 } 48 EVP_KDF_free(kdf); 49 return ret; 50 } 51 52 /*- 53 * The old name for ecdh_KDF_X9_63 54 * Retained for ABI compatibility 55 */ 56 #ifndef OPENSSL_NO_DEPRECATED_3_0 57 int ECDH_KDF_X9_62(unsigned char *out, size_t outlen, 58 const unsigned char *Z, size_t Zlen, 59 const unsigned char *sinfo, size_t sinfolen, 60 const EVP_MD *md) 61 { 62 return ossl_ecdh_kdf_X9_63(out, outlen, Z, Zlen, sinfo, sinfolen, md, NULL, 63 NULL); 64 } 65 #endif 66