1 /*
2  * Copyright 2013-2021 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  * DH low level APIs are deprecated for public use, but still ok for
12  * internal use.
13  */
14 #include "internal/deprecated.h"
15 
16 #include "e_os.h"
17 #include "e_os.h"
18 #include <string.h>
19 #include <openssl/core_names.h>
20 #include <openssl/dh.h>
21 #include <openssl/evp.h>
22 #include <openssl/asn1.h>
23 #include <openssl/kdf.h>
24 #include "internal/provider.h"
25 #include "crypto/dh.h"
26 
27 /* Key derivation function from X9.63/SECG */
ossl_dh_kdf_X9_42_asn1(unsigned char * out,size_t outlen,const unsigned char * Z,size_t Zlen,const char * cek_alg,const unsigned char * ukm,size_t ukmlen,const EVP_MD * md,OSSL_LIB_CTX * libctx,const char * propq)28 int ossl_dh_kdf_X9_42_asn1(unsigned char *out, size_t outlen,
29                            const unsigned char *Z, size_t Zlen,
30                            const char *cek_alg,
31                            const unsigned char *ukm, size_t ukmlen,
32                            const EVP_MD *md,
33                            OSSL_LIB_CTX *libctx, const char *propq)
34 {
35     int ret = 0;
36     EVP_KDF_CTX *kctx = NULL;
37     EVP_KDF *kdf = NULL;
38     OSSL_PARAM params[5], *p = params;
39     const char *mdname = EVP_MD_get0_name(md);
40 
41     kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_X942KDF_ASN1, propq);
42     kctx = EVP_KDF_CTX_new(kdf);
43     if (kctx == NULL)
44         goto err;
45 
46     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
47                                             (char *)mdname, 0);
48     *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
49                                              (unsigned char *)Z, Zlen);
50     if (ukm != NULL)
51         *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_UKM,
52                                                  (unsigned char *)ukm, ukmlen);
53     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_CEK_ALG,
54                                             (char *)cek_alg, 0);
55     *p = OSSL_PARAM_construct_end();
56     ret = EVP_KDF_derive(kctx, out, outlen, params) > 0;
57 err:
58     EVP_KDF_CTX_free(kctx);
59     EVP_KDF_free(kdf);
60     return ret;
61 }
62 
63 #if !defined(FIPS_MODULE)
DH_KDF_X9_42(unsigned char * out,size_t outlen,const unsigned char * Z,size_t Zlen,ASN1_OBJECT * key_oid,const unsigned char * ukm,size_t ukmlen,const EVP_MD * md)64 int DH_KDF_X9_42(unsigned char *out, size_t outlen,
65                  const unsigned char *Z, size_t Zlen,
66                  ASN1_OBJECT *key_oid,
67                  const unsigned char *ukm, size_t ukmlen, const EVP_MD *md)
68 {
69     char key_alg[OSSL_MAX_NAME_SIZE];
70     const OSSL_PROVIDER *prov = EVP_MD_get0_provider(md);
71     OSSL_LIB_CTX *libctx = ossl_provider_libctx(prov);
72 
73     if (!OBJ_obj2txt(key_alg, sizeof(key_alg), key_oid, 0))
74         return 0;
75 
76     return ossl_dh_kdf_X9_42_asn1(out, outlen, Z, Zlen, key_alg,
77                                   ukm, ukmlen, md, libctx, NULL);
78 }
79 #endif /* !defined(FIPS_MODULE) */
80