xref: /openbsd-src/lib/libcrypto/dh/dh_lib.c (revision ce6fc0900b2b4e5edea1b1b8e032cab822e464e9)
1 /* crypto/dh/dh_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 #include <stdio.h>
60 #include "cryptlib.h"
61 #include <openssl/bn.h>
62 #include <openssl/dh.h>
63 #include <openssl/engine.h>
64 
65 const char *DH_version="Diffie-Hellman" OPENSSL_VERSION_PTEXT;
66 
67 static DH_METHOD *default_DH_method;
68 static int dh_meth_num = 0;
69 static STACK_OF(CRYPTO_EX_DATA_FUNCS) *dh_meth = NULL;
70 
71 void DH_set_default_openssl_method(DH_METHOD *meth)
72 {
73 	ENGINE *e;
74 	/* We'll need to notify the "openssl" ENGINE of this
75 	 * change too. We won't bother locking things down at
76 	 * our end as there was never any locking in these
77 	 * functions! */
78 	if(default_DH_method != meth)
79 		{
80 		default_DH_method = meth;
81 		e = ENGINE_by_id("openssl");
82 		if(e)
83 			{
84 			ENGINE_set_DH(e, meth);
85 			ENGINE_free(e);
86 			}
87 		}
88 }
89 
90 DH_METHOD *DH_get_default_openssl_method(void)
91 {
92 	if(!default_DH_method) default_DH_method = DH_OpenSSL();
93 	return default_DH_method;
94 }
95 
96 #if 0
97 DH_METHOD *DH_set_method(DH *dh, DH_METHOD *meth)
98 {
99         DH_METHOD *mtmp;
100         mtmp = dh->meth;
101         if (mtmp->finish) mtmp->finish(dh);
102         dh->meth = meth;
103         if (meth->init) meth->init(dh);
104         return mtmp;
105 }
106 #else
107 int DH_set_method(DH *dh, ENGINE *engine)
108 {
109 	ENGINE *mtmp;
110 	DH_METHOD *meth;
111 	mtmp = dh->engine;
112 	meth = ENGINE_get_DH(mtmp);
113 	if (!ENGINE_init(engine))
114 		return 0;
115 	if (meth->finish) meth->finish(dh);
116 	dh->engine= engine;
117 	meth = ENGINE_get_DH(engine);
118 	if (meth->init) meth->init(dh);
119 	/* SHOULD ERROR CHECK THIS!!! */
120 	ENGINE_finish(mtmp);
121 	return 1;
122 }
123 #endif
124 
125 DH *DH_new(void)
126 {
127 	return DH_new_method(NULL);
128 }
129 
130 #if 0
131 DH *DH_new_method(DH_METHOD *meth)
132 #else
133 DH *DH_new_method(ENGINE *engine)
134 #endif
135 	{
136 	DH_METHOD *meth;
137 	DH *ret;
138 	ret=(DH *)OPENSSL_malloc(sizeof(DH));
139 
140 	if (ret == NULL)
141 		{
142 		DHerr(DH_F_DH_NEW,ERR_R_MALLOC_FAILURE);
143 		return(NULL);
144 		}
145 	if(engine)
146 		ret->engine = engine;
147 	else
148 		{
149 		if((ret->engine=ENGINE_get_default_DH()) == NULL)
150 			{
151 			OPENSSL_free(ret);
152 			return NULL;
153 			}
154 		}
155 	meth = ENGINE_get_DH(ret->engine);
156 	ret->pad=0;
157 	ret->version=0;
158 	ret->p=NULL;
159 	ret->g=NULL;
160 	ret->length=0;
161 	ret->pub_key=NULL;
162 	ret->priv_key=NULL;
163 	ret->q=NULL;
164 	ret->j=NULL;
165 	ret->seed = NULL;
166 	ret->seedlen = 0;
167 	ret->counter = NULL;
168 	ret->method_mont_p=NULL;
169 	ret->references = 1;
170 	ret->flags=meth->flags;
171 	CRYPTO_new_ex_data(dh_meth,ret,&ret->ex_data);
172 	if ((meth->init != NULL) && !meth->init(ret))
173 		{
174 		CRYPTO_free_ex_data(dh_meth,ret,&ret->ex_data);
175 		OPENSSL_free(ret);
176 		ret=NULL;
177 		}
178 	return(ret);
179 	}
180 
181 void DH_free(DH *r)
182 	{
183 	DH_METHOD *meth;
184 	int i;
185 	if(r == NULL) return;
186 	i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH);
187 #ifdef REF_PRINT
188 	REF_PRINT("DH",r);
189 #endif
190 	if (i > 0) return;
191 #ifdef REF_CHECK
192 	if (i < 0)
193 		{
194 		fprintf(stderr,"DH_free, bad reference count\n");
195 		abort();
196 	}
197 #endif
198 
199 	meth = ENGINE_get_DH(r->engine);
200 	if(meth->finish) meth->finish(r);
201 	ENGINE_finish(r->engine);
202 
203 	CRYPTO_free_ex_data(dh_meth, r, &r->ex_data);
204 
205 	if (r->p != NULL) BN_clear_free(r->p);
206 	if (r->g != NULL) BN_clear_free(r->g);
207 	if (r->q != NULL) BN_clear_free(r->q);
208 	if (r->j != NULL) BN_clear_free(r->j);
209 	if (r->seed) OPENSSL_free(r->seed);
210 	if (r->counter != NULL) BN_clear_free(r->counter);
211 	if (r->pub_key != NULL) BN_clear_free(r->pub_key);
212 	if (r->priv_key != NULL) BN_clear_free(r->priv_key);
213 	OPENSSL_free(r);
214 	}
215 
216 int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
217 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
218         {
219 	dh_meth_num++;
220 	return(CRYPTO_get_ex_new_index(dh_meth_num-1,
221 		&dh_meth,argl,argp,new_func,dup_func,free_func));
222         }
223 
224 int DH_set_ex_data(DH *d, int idx, void *arg)
225 	{
226 	return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
227 	}
228 
229 void *DH_get_ex_data(DH *d, int idx)
230 	{
231 	return(CRYPTO_get_ex_data(&d->ex_data,idx));
232 	}
233 
234 int DH_size(DH *dh)
235 	{
236 	return(BN_num_bytes(dh->p));
237 	}
238