1 /*
2 * Copyright 2020-2023 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 <openssl/err.h>
17 #include <openssl/core_names.h>
18 #ifndef FIPS_MODULE
19 #include <openssl/x509.h>
20 #endif
21 #include "internal/param_build_set.h"
22 #include "crypto/dh.h"
23 #include "dh_local.h"
24
25 /*
26 * The intention with the "backend" source file is to offer backend functions
27 * for legacy backends (EVP_PKEY_ASN1_METHOD and EVP_PKEY_METHOD) and provider
28 * implementations alike.
29 */
30
dh_ffc_params_fromdata(DH * dh,const OSSL_PARAM params[])31 static int dh_ffc_params_fromdata(DH *dh, const OSSL_PARAM params[])
32 {
33 int ret;
34 FFC_PARAMS *ffc = ossl_dh_get0_params(dh);
35
36 ret = ossl_ffc_params_fromdata(ffc, params);
37 if (ret)
38 ossl_dh_cache_named_group(dh); /* This increments dh->dirty_cnt */
39 return ret;
40 }
41
ossl_dh_params_fromdata(DH * dh,const OSSL_PARAM params[])42 int ossl_dh_params_fromdata(DH *dh, const OSSL_PARAM params[])
43 {
44 const OSSL_PARAM *param_priv_len;
45 long priv_len;
46
47 if (!dh_ffc_params_fromdata(dh, params))
48 return 0;
49
50 param_priv_len = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_DH_PRIV_LEN);
51 if (param_priv_len != NULL
52 && (!OSSL_PARAM_get_long(param_priv_len, &priv_len)
53 || !DH_set_length(dh, priv_len)))
54 return 0;
55
56 return 1;
57 }
58
ossl_dh_key_fromdata(DH * dh,const OSSL_PARAM params[],int include_private)59 int ossl_dh_key_fromdata(DH *dh, const OSSL_PARAM params[], int include_private)
60 {
61 const OSSL_PARAM *param_priv_key, *param_pub_key;
62 BIGNUM *priv_key = NULL, *pub_key = NULL;
63
64 if (dh == NULL)
65 return 0;
66
67 param_priv_key = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PRIV_KEY);
68 param_pub_key = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PUB_KEY);
69
70 if (include_private
71 && param_priv_key != NULL
72 && !OSSL_PARAM_get_BN(param_priv_key, &priv_key))
73 goto err;
74
75 if (param_pub_key != NULL
76 && !OSSL_PARAM_get_BN(param_pub_key, &pub_key))
77 goto err;
78
79 if (!DH_set0_key(dh, pub_key, priv_key))
80 goto err;
81
82 return 1;
83
84 err:
85 BN_clear_free(priv_key);
86 BN_free(pub_key);
87 return 0;
88 }
89
ossl_dh_params_todata(DH * dh,OSSL_PARAM_BLD * bld,OSSL_PARAM params[])90 int ossl_dh_params_todata(DH *dh, OSSL_PARAM_BLD *bld, OSSL_PARAM params[])
91 {
92 long l = DH_get_length(dh);
93
94 if (!ossl_ffc_params_todata(ossl_dh_get0_params(dh), bld, params))
95 return 0;
96 if (l > 0
97 && !ossl_param_build_set_long(bld, params, OSSL_PKEY_PARAM_DH_PRIV_LEN, l))
98 return 0;
99 return 1;
100 }
101
ossl_dh_key_todata(DH * dh,OSSL_PARAM_BLD * bld,OSSL_PARAM params[],int include_private)102 int ossl_dh_key_todata(DH *dh, OSSL_PARAM_BLD *bld, OSSL_PARAM params[],
103 int include_private)
104 {
105 const BIGNUM *priv = NULL, *pub = NULL;
106
107 if (dh == NULL)
108 return 0;
109
110 DH_get0_key(dh, &pub, &priv);
111 if (priv != NULL
112 && include_private
113 && !ossl_param_build_set_bn(bld, params, OSSL_PKEY_PARAM_PRIV_KEY, priv))
114 return 0;
115 if (pub != NULL
116 && !ossl_param_build_set_bn(bld, params, OSSL_PKEY_PARAM_PUB_KEY, pub))
117 return 0;
118
119 return 1;
120 }
121
ossl_dh_is_foreign(const DH * dh)122 int ossl_dh_is_foreign(const DH *dh)
123 {
124 #ifndef FIPS_MODULE
125 if (dh->engine != NULL || ossl_dh_get_method(dh) != DH_OpenSSL())
126 return 1;
127 #endif
128 return 0;
129 }
130
dh_bn_dup_check(BIGNUM ** out,const BIGNUM * f)131 static ossl_inline int dh_bn_dup_check(BIGNUM **out, const BIGNUM *f)
132 {
133 if (f != NULL && (*out = BN_dup(f)) == NULL)
134 return 0;
135 return 1;
136 }
137
ossl_dh_dup(const DH * dh,int selection)138 DH *ossl_dh_dup(const DH *dh, int selection)
139 {
140 DH *dupkey = NULL;
141
142 /* Do not try to duplicate foreign DH keys */
143 if (ossl_dh_is_foreign(dh))
144 return NULL;
145
146 if ((dupkey = ossl_dh_new_ex(dh->libctx)) == NULL)
147 return NULL;
148
149 dupkey->length = DH_get_length(dh);
150 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0
151 && !ossl_ffc_params_copy(&dupkey->params, &dh->params))
152 goto err;
153
154 dupkey->flags = dh->flags;
155
156 if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0
157 && ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0
158 || !dh_bn_dup_check(&dupkey->pub_key, dh->pub_key)))
159 goto err;
160
161 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0
162 && ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0
163 || !dh_bn_dup_check(&dupkey->priv_key, dh->priv_key)))
164 goto err;
165
166 #ifndef FIPS_MODULE
167 if (!CRYPTO_dup_ex_data(CRYPTO_EX_INDEX_DH,
168 &dupkey->ex_data, &dh->ex_data))
169 goto err;
170 #endif
171
172 return dupkey;
173
174 err:
175 DH_free(dupkey);
176 return NULL;
177 }
178
179 #ifndef FIPS_MODULE
ossl_dh_key_from_pkcs8(const PKCS8_PRIV_KEY_INFO * p8inf,OSSL_LIB_CTX * libctx,const char * propq)180 DH *ossl_dh_key_from_pkcs8(const PKCS8_PRIV_KEY_INFO *p8inf,
181 OSSL_LIB_CTX *libctx, const char *propq)
182 {
183 const unsigned char *p, *pm;
184 int pklen, pmlen;
185 int ptype;
186 const void *pval;
187 const ASN1_STRING *pstr;
188 const X509_ALGOR *palg;
189 BIGNUM *privkey_bn = NULL;
190 ASN1_INTEGER *privkey = NULL;
191 DH *dh = NULL;
192
193 if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8inf))
194 return 0;
195
196 X509_ALGOR_get0(NULL, &ptype, &pval, palg);
197
198 if (ptype != V_ASN1_SEQUENCE)
199 goto decerr;
200 if ((privkey = d2i_ASN1_INTEGER(NULL, &p, pklen)) == NULL)
201 goto decerr;
202
203 pstr = pval;
204 pm = pstr->data;
205 pmlen = pstr->length;
206 switch (OBJ_obj2nid(palg->algorithm)) {
207 case NID_dhKeyAgreement:
208 dh = d2i_DHparams(NULL, &pm, pmlen);
209 break;
210 case NID_dhpublicnumber:
211 dh = d2i_DHxparams(NULL, &pm, pmlen);
212 break;
213 default:
214 goto decerr;
215 }
216 if (dh == NULL)
217 goto decerr;
218
219 /* We have parameters now set private key */
220 if ((privkey_bn = BN_secure_new()) == NULL
221 || !ASN1_INTEGER_to_BN(privkey, privkey_bn)) {
222 ERR_raise(ERR_LIB_DH, DH_R_BN_ERROR);
223 BN_clear_free(privkey_bn);
224 goto dherr;
225 }
226 if (!DH_set0_key(dh, NULL, privkey_bn))
227 goto dherr;
228 /* Calculate public key, increments dirty_cnt */
229 if (!DH_generate_key(dh))
230 goto dherr;
231
232 goto done;
233
234 decerr:
235 ERR_raise(ERR_LIB_DH, EVP_R_DECODE_ERROR);
236 dherr:
237 DH_free(dh);
238 dh = NULL;
239 done:
240 ASN1_STRING_clear_free(privkey);
241 return dh;
242 }
243 #endif
244