xref: /openbsd/lib/libcrypto/dsa/dsa_lib.c (revision 404b540a)
1 /* crypto/dsa/dsa_lib.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 /* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
60 
61 #include <stdio.h>
62 #include "cryptlib.h"
63 #include <openssl/bn.h>
64 #include <openssl/dsa.h>
65 #include <openssl/asn1.h>
66 #ifndef OPENSSL_NO_ENGINE
67 #include <openssl/engine.h>
68 #endif
69 #ifndef OPENSSL_NO_DH
70 #include <openssl/dh.h>
71 #endif
72 
73 const char DSA_version[]="DSA" OPENSSL_VERSION_PTEXT;
74 
75 static const DSA_METHOD *default_DSA_method = NULL;
76 
77 void DSA_set_default_method(const DSA_METHOD *meth)
78 	{
79 #ifdef OPENSSL_FIPS
80 	if (FIPS_mode() && !(meth->flags & DSA_FLAG_FIPS_METHOD))
81 		{
82 		DSAerr(DSA_F_DSA_SET_DEFAULT_METHOD, DSA_R_NON_FIPS_METHOD);
83 		return;
84 		}
85 #endif
86 
87 	default_DSA_method = meth;
88 	}
89 
90 const DSA_METHOD *DSA_get_default_method(void)
91 	{
92 	if(!default_DSA_method)
93 		default_DSA_method = DSA_OpenSSL();
94 	return default_DSA_method;
95 	}
96 
97 DSA *DSA_new(void)
98 	{
99 	return DSA_new_method(NULL);
100 	}
101 
102 int DSA_set_method(DSA *dsa, const DSA_METHOD *meth)
103 	{
104 	/* NB: The caller is specifically setting a method, so it's not up to us
105 	 * to deal with which ENGINE it comes from. */
106         const DSA_METHOD *mtmp;
107 #ifdef OPENSSL_FIPS
108 	if (FIPS_mode() && !(meth->flags & DSA_FLAG_FIPS_METHOD))
109 		{
110 		DSAerr(DSA_F_DSA_SET_METHOD, DSA_R_NON_FIPS_METHOD);
111 		return 0;
112 		}
113 #endif
114         mtmp = dsa->meth;
115         if (mtmp->finish) mtmp->finish(dsa);
116 #ifndef OPENSSL_NO_ENGINE
117 	if (dsa->engine)
118 		{
119 		ENGINE_finish(dsa->engine);
120 		dsa->engine = NULL;
121 		}
122 #endif
123         dsa->meth = meth;
124         if (meth->init) meth->init(dsa);
125         return 1;
126 	}
127 
128 DSA *DSA_new_method(ENGINE *engine)
129 	{
130 	DSA *ret;
131 
132 	ret=(DSA *)OPENSSL_malloc(sizeof(DSA));
133 	if (ret == NULL)
134 		{
135 		DSAerr(DSA_F_DSA_NEW_METHOD,ERR_R_MALLOC_FAILURE);
136 		return(NULL);
137 		}
138 	ret->meth = DSA_get_default_method();
139 #ifndef OPENSSL_NO_ENGINE
140 	if (engine)
141 		{
142 		if (!ENGINE_init(engine))
143 			{
144 			DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_ENGINE_LIB);
145 			OPENSSL_free(ret);
146 			return NULL;
147 			}
148 		ret->engine = engine;
149 		}
150 	else
151 		ret->engine = ENGINE_get_default_DSA();
152 	if(ret->engine)
153 		{
154 		ret->meth = ENGINE_get_DSA(ret->engine);
155 		if(!ret->meth)
156 			{
157 			DSAerr(DSA_F_DSA_NEW_METHOD,
158 				ERR_R_ENGINE_LIB);
159 			ENGINE_finish(ret->engine);
160 			OPENSSL_free(ret);
161 			return NULL;
162 			}
163 		}
164 #endif
165 #ifdef OPENSSL_FIPS
166 	if (FIPS_mode() && !(ret->meth->flags & DSA_FLAG_FIPS_METHOD))
167 		{
168 		DSAerr(DSA_F_DSA_NEW_METHOD, DSA_R_NON_FIPS_METHOD);
169 #ifndef OPENSSL_NO_ENGINE
170 		if (ret->engine)
171 			ENGINE_finish(ret->engine);
172 #endif
173 		OPENSSL_free(ret);
174 		return NULL;
175 		}
176 #endif
177 
178 	ret->pad=0;
179 	ret->version=0;
180 	ret->write_params=1;
181 	ret->p=NULL;
182 	ret->q=NULL;
183 	ret->g=NULL;
184 
185 	ret->pub_key=NULL;
186 	ret->priv_key=NULL;
187 
188 	ret->kinv=NULL;
189 	ret->r=NULL;
190 	ret->method_mont_p=NULL;
191 
192 	ret->references=1;
193 	ret->flags=ret->meth->flags;
194 	CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
195 	if ((ret->meth->init != NULL) && !ret->meth->init(ret))
196 		{
197 #ifndef OPENSSL_NO_ENGINE
198 		if (ret->engine)
199 			ENGINE_finish(ret->engine);
200 #endif
201 		CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
202 		OPENSSL_free(ret);
203 		ret=NULL;
204 		}
205 
206 	return(ret);
207 	}
208 
209 void DSA_free(DSA *r)
210 	{
211 	int i;
212 
213 	if (r == NULL) return;
214 
215 	i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_DSA);
216 #ifdef REF_PRINT
217 	REF_PRINT("DSA",r);
218 #endif
219 	if (i > 0) return;
220 #ifdef REF_CHECK
221 	if (i < 0)
222 		{
223 		fprintf(stderr,"DSA_free, bad reference count\n");
224 		abort();
225 		}
226 #endif
227 
228 	if(r->meth->finish)
229 		r->meth->finish(r);
230 #ifndef OPENSSL_NO_ENGINE
231 	if(r->engine)
232 		ENGINE_finish(r->engine);
233 #endif
234 
235 	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, r, &r->ex_data);
236 
237 	if (r->p != NULL) BN_clear_free(r->p);
238 	if (r->q != NULL) BN_clear_free(r->q);
239 	if (r->g != NULL) BN_clear_free(r->g);
240 	if (r->pub_key != NULL) BN_clear_free(r->pub_key);
241 	if (r->priv_key != NULL) BN_clear_free(r->priv_key);
242 	if (r->kinv != NULL) BN_clear_free(r->kinv);
243 	if (r->r != NULL) BN_clear_free(r->r);
244 	OPENSSL_free(r);
245 	}
246 
247 int DSA_up_ref(DSA *r)
248 	{
249 	int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DSA);
250 #ifdef REF_PRINT
251 	REF_PRINT("DSA",r);
252 #endif
253 #ifdef REF_CHECK
254 	if (i < 2)
255 		{
256 		fprintf(stderr, "DSA_up_ref, bad reference count\n");
257 		abort();
258 		}
259 #endif
260 	return ((i > 1) ? 1 : 0);
261 	}
262 
263 int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
264 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
265         {
266 	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DSA, argl, argp,
267 				new_func, dup_func, free_func);
268         }
269 
270 int DSA_set_ex_data(DSA *d, int idx, void *arg)
271 	{
272 	return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
273 	}
274 
275 void *DSA_get_ex_data(DSA *d, int idx)
276 	{
277 	return(CRYPTO_get_ex_data(&d->ex_data,idx));
278 	}
279 
280 #ifndef OPENSSL_NO_DH
281 DH *DSA_dup_DH(const DSA *r)
282 	{
283 	/* DSA has p, q, g, optional pub_key, optional priv_key.
284 	 * DH has p, optional length, g, optional pub_key, optional priv_key.
285 	 */
286 
287 	DH *ret = NULL;
288 
289 	if (r == NULL)
290 		goto err;
291 	ret = DH_new();
292 	if (ret == NULL)
293 		goto err;
294 	if (r->p != NULL)
295 		if ((ret->p = BN_dup(r->p)) == NULL)
296 			goto err;
297 	if (r->q != NULL)
298 		ret->length = BN_num_bits(r->q);
299 	if (r->g != NULL)
300 		if ((ret->g = BN_dup(r->g)) == NULL)
301 			goto err;
302 	if (r->pub_key != NULL)
303 		if ((ret->pub_key = BN_dup(r->pub_key)) == NULL)
304 			goto err;
305 	if (r->priv_key != NULL)
306 		if ((ret->priv_key = BN_dup(r->priv_key)) == NULL)
307 			goto err;
308 
309 	return ret;
310 
311  err:
312 	if (ret != NULL)
313 		DH_free(ret);
314 	return NULL;
315 	}
316 #endif
317