2 * Copyright 2017-2022 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"
27 static DH *dh_param_init(OSSL_LIB_CTX *libctx, const DH_NAMED_GROUP *group)
29 DH *dh = ossl_dh_new_ex(libctx);
34 ossl_ffc_named_group_set_pqg(&dh->params, group);
35 dh->params.nid = ossl_ffc_named_group_get_uid(group);
40 DH *ossl_dh_new_by_nid_ex(OSSL_LIB_CTX *libctx, int nid)
42 const DH_NAMED_GROUP *group;
44 if ((group = ossl_ffc_uid_to_dh_named_group(nid)) != NULL)
45 return dh_param_init(libctx, group);
47 ERR_raise(ERR_LIB_DH, DH_R_INVALID_PARAMETER_NID);
51 DH *DH_new_by_nid(int nid)
53 return ossl_dh_new_by_nid_ex(NULL, nid);
56 void ossl_dh_cache_named_group(DH *dh)
58 const DH_NAMED_GROUP *group;
63 dh->params.nid = NID_undef; /* flush cached value */
65 /* Exit if p or g is not set */
66 if (dh->params.p == NULL
67 || dh->params.g == NULL)
70 if ((group = ossl_ffc_numbers_to_dh_named_group(dh->params.p,
72 dh->params.g)) != NULL) {
73 if (dh->params.q == NULL)
74 dh->params.q = (BIGNUM *)ossl_ffc_named_group_get_q(group);
76 dh->params.nid = ossl_ffc_named_group_get_uid(group);
81 int ossl_dh_is_named_safe_prime_group(const DH *dh)
83 int id = DH_get_nid(dh);
86 * Exclude RFC5114 groups (id = 1..3) since they do not have
92 int DH_get_nid(const DH *dh)
97 return dh->params.nid;