kdf: make function naming consistent.
[openssl.git] / crypto / ec / ecdh_kdf.c
1 /*
2  * Copyright 2015-2020 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 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 {
29     int ret = 0;
30     EVP_KDF_CTX *kctx = NULL;
31     OSSL_PARAM params[4], *p = params;
32     const char *mdname = EVP_MD_name(md);
33     EVP_KDF *kdf = EVP_KDF_fetch(NULL, OSSL_KDF_NAME_X963KDF, NULL);
34
35     if ((kctx = EVP_KDF_new_ctx(kdf)) != NULL) {
36         *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
37                                                 (char *)mdname, 0);
38         *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
39                                                  (void *)Z, Zlen);
40         *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_INFO,
41                                                  (void *)sinfo, sinfolen);
42         *p = OSSL_PARAM_construct_end();
43
44         ret = EVP_KDF_set_ctx_params(kctx, params) > 0
45             && EVP_KDF_derive(kctx, out, outlen) > 0;
46         EVP_KDF_free_ctx(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 ecdh_KDF_X9_63(out, outlen, Z, Zlen, sinfo, sinfolen, md);
63 }
64 #endif