2 * Copyright 2017-2020 The OpenSSL Project Authors. All Rights Reserved.
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
10 /* DH parameters from RFC7919 and RFC3526 */
13 * DH low level APIs are deprecated for public use, but still ok for
16 #include "internal/deprecated.h"
19 #include "internal/cryptlib.h"
20 #include "internal/ffc.h"
22 #include <openssl/bn.h>
23 #include <openssl/objects.h>
24 #include "internal/nelem.h"
25 #include "crypto/dh.h"
26 #include "e_os.h" /* strcasecmp */
28 static DH *dh_param_init(OSSL_LIB_CTX *libctx, const DH_NAMED_GROUP *group)
30 DH *dh = dh_new_ex(libctx);
35 ossl_ffc_named_group_set_pqg(&dh->params, group);
36 dh->params.nid = ossl_ffc_named_group_get_uid(group);
37 dh->length = BN_num_bits(dh->params.q);
42 DH *dh_new_by_nid_ex(OSSL_LIB_CTX *libctx, int nid)
44 const DH_NAMED_GROUP *group;
46 if ((group = ossl_ffc_uid_to_dh_named_group(nid)) != NULL)
47 return dh_param_init(libctx, group);
49 ERR_raise(ERR_LIB_DH, DH_R_INVALID_PARAMETER_NID);
53 DH *DH_new_by_nid(int nid)
55 return dh_new_by_nid_ex(NULL, nid);
58 void dh_cache_named_group(DH *dh)
60 const DH_NAMED_GROUP *group;
65 dh->params.nid = NID_undef; /* flush cached value */
67 /* Exit if p or g is not set */
68 if (dh->params.p == NULL
69 || dh->params.g == NULL)
72 if ((group = ossl_ffc_numbers_to_dh_named_group(dh->params.p,
74 dh->params.g)) != NULL) {
75 if (dh->params.q == NULL)
76 dh->params.q = (BIGNUM *)ossl_ffc_named_group_get_q(group);
78 dh->params.nid = ossl_ffc_named_group_get_uid(group);
79 dh->length = BN_num_bits(dh->params.q);
84 int DH_get_nid(const DH *dh)
89 return dh->params.nid;