2 * Copyright 2020-2022 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
11 * DSA low level APIs are deprecated for public use, but still ok for
14 #include "internal/deprecated.h"
16 #include <openssl/core_names.h>
17 #include <openssl/err.h>
19 # include <openssl/x509.h>
21 #include "crypto/dsa.h"
22 #include "dsa_local.h"
25 * The intention with the "backend" source file is to offer backend support
26 * for legacy backends (EVP_PKEY_ASN1_METHOD and EVP_PKEY_METHOD) and provider
27 * implementations alike.
30 int ossl_dsa_key_fromdata(DSA *dsa, const OSSL_PARAM params[],
33 const OSSL_PARAM *param_priv_key = NULL, *param_pub_key;
34 BIGNUM *priv_key = NULL, *pub_key = NULL;
39 if (include_private) {
41 OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PRIV_KEY);
44 OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PUB_KEY);
46 /* It's ok if neither half is present */
47 if (param_priv_key == NULL && param_pub_key == NULL)
50 if (param_pub_key != NULL && !OSSL_PARAM_get_BN(param_pub_key, &pub_key))
52 if (param_priv_key != NULL && !OSSL_PARAM_get_BN(param_priv_key, &priv_key))
55 if (!DSA_set0_key(dsa, pub_key, priv_key))
61 BN_clear_free(priv_key);
66 int ossl_dsa_is_foreign(const DSA *dsa)
69 if (dsa->engine != NULL || DSA_get_method((DSA *)dsa) != DSA_OpenSSL())
75 static ossl_inline int dsa_bn_dup_check(BIGNUM **out, const BIGNUM *f)
77 if (f != NULL && (*out = BN_dup(f)) == NULL)
82 DSA *ossl_dsa_dup(const DSA *dsa, int selection)
86 /* Do not try to duplicate foreign DSA keys */
87 if (ossl_dsa_is_foreign(dsa))
90 if ((dupkey = ossl_dsa_new(dsa->libctx)) == NULL)
93 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0
94 && !ossl_ffc_params_copy(&dupkey->params, &dsa->params))
97 dupkey->flags = dsa->flags;
99 if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0
100 && ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0
101 || !dsa_bn_dup_check(&dupkey->pub_key, dsa->pub_key)))
104 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0
105 && ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0
106 || !dsa_bn_dup_check(&dupkey->priv_key, dsa->priv_key)))
110 if (!CRYPTO_dup_ex_data(CRYPTO_EX_INDEX_DSA,
111 &dupkey->ex_data, &dsa->ex_data))
123 DSA *ossl_dsa_key_from_pkcs8(const PKCS8_PRIV_KEY_INFO *p8inf,
124 OSSL_LIB_CTX *libctx, const char *propq)
126 const unsigned char *p, *pm;
130 const ASN1_STRING *pstr;
131 const X509_ALGOR *palg;
132 ASN1_INTEGER *privkey = NULL;
133 const BIGNUM *dsa_p, *dsa_g;
134 BIGNUM *dsa_pubkey = NULL, *dsa_privkey = NULL;
139 if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8inf))
141 X509_ALGOR_get0(NULL, &ptype, &pval, palg);
143 if ((privkey = d2i_ASN1_INTEGER(NULL, &p, pklen)) == NULL)
145 if (privkey->type == V_ASN1_NEG_INTEGER || ptype != V_ASN1_SEQUENCE)
150 pmlen = pstr->length;
151 if ((dsa = d2i_DSAparams(NULL, &pm, pmlen)) == NULL)
153 /* We have parameters now set private key */
154 if ((dsa_privkey = BN_secure_new()) == NULL
155 || !ASN1_INTEGER_to_BN(privkey, dsa_privkey)) {
156 ERR_raise(ERR_LIB_DSA, DSA_R_BN_ERROR);
159 /* Calculate public key */
160 if ((dsa_pubkey = BN_new()) == NULL) {
161 ERR_raise(ERR_LIB_DSA, ERR_R_BN_LIB);
164 if ((ctx = BN_CTX_new()) == NULL) {
165 ERR_raise(ERR_LIB_DSA, ERR_R_BN_LIB);
169 dsa_p = DSA_get0_p(dsa);
170 dsa_g = DSA_get0_g(dsa);
171 BN_set_flags(dsa_privkey, BN_FLG_CONSTTIME);
172 if (!BN_mod_exp(dsa_pubkey, dsa_g, dsa_privkey, dsa_p, ctx)) {
173 ERR_raise(ERR_LIB_DSA, DSA_R_BN_ERROR);
176 if (!DSA_set0_key(dsa, dsa_pubkey, dsa_privkey)) {
177 ERR_raise(ERR_LIB_DSA, ERR_R_INTERNAL_ERROR);
184 ERR_raise(ERR_LIB_DSA, DSA_R_DECODE_ERROR);
186 BN_free(dsa_privkey);
192 ASN1_STRING_clear_free(privkey);