dh_lib.c revision 267654 
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#ifndef OPENSSL_NO_ENGINE
64#include <openssl/engine.h>
65#endif
66
67const char DH_version[]="Diffie-Hellman" OPENSSL_VERSION_PTEXT;
68
69static const DH_METHOD *default_DH_method = NULL;
70
71void DH_set_default_method(const DH_METHOD *meth)
72	{
73	default_DH_method = meth;
74	}
75
76const DH_METHOD *DH_get_default_method(void)
77	{
78	if(!default_DH_method)
79		default_DH_method = DH_OpenSSL();
80	return default_DH_method;
81	}
82
83int DH_set_method(DH *dh, const DH_METHOD *meth)
84	{
85	/* NB: The caller is specifically setting a method, so it's not up to us
86	 * to deal with which ENGINE it comes from. */
87        const DH_METHOD *mtmp;
88        mtmp = dh->meth;
89        if (mtmp->finish) mtmp->finish(dh);
90#ifndef OPENSSL_NO_ENGINE
91	if (dh->engine)
92		{
93		ENGINE_finish(dh->engine);
94		dh->engine = NULL;
95		}
96#endif
97        dh->meth = meth;
98        if (meth->init) meth->init(dh);
99        return 1;
100	}
101
102DH *DH_new(void)
103	{
104	return DH_new_method(NULL);
105	}
106
107DH *DH_new_method(ENGINE *engine)
108	{
109	DH *ret;
110
111	ret=(DH *)OPENSSL_malloc(sizeof(DH));
112	if (ret == NULL)
113		{
114		DHerr(DH_F_DH_NEW_METHOD,ERR_R_MALLOC_FAILURE);
115		return(NULL);
116		}
117
118	ret->meth = DH_get_default_method();
119#ifndef OPENSSL_NO_ENGINE
120	if (engine)
121		{
122		if (!ENGINE_init(engine))
123			{
124			DHerr(DH_F_DH_NEW_METHOD, ERR_R_ENGINE_LIB);
125			OPENSSL_free(ret);
126			return NULL;
127			}
128		ret->engine = engine;
129		}
130	else
131		ret->engine = ENGINE_get_default_DH();
132	if(ret->engine)
133		{
134		ret->meth = ENGINE_get_DH(ret->engine);
135		if(!ret->meth)
136			{
137			DHerr(DH_F_DH_NEW_METHOD,ERR_R_ENGINE_LIB);
138			ENGINE_finish(ret->engine);
139			OPENSSL_free(ret);
140			return NULL;
141			}
142		}
143#endif
144
145	ret->pad=0;
146	ret->version=0;
147	ret->p=NULL;
148	ret->g=NULL;
149	ret->length=0;
150	ret->pub_key=NULL;
151	ret->priv_key=NULL;
152	ret->q=NULL;
153	ret->j=NULL;
154	ret->seed = NULL;
155	ret->seedlen = 0;
156	ret->counter = NULL;
157	ret->method_mont_p=NULL;
158	ret->references = 1;
159	ret->flags=ret->meth->flags;
160	CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
161	if ((ret->meth->init != NULL) && !ret->meth->init(ret))
162		{
163#ifndef OPENSSL_NO_ENGINE
164		if (ret->engine)
165			ENGINE_finish(ret->engine);
166#endif
167		CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
168		OPENSSL_free(ret);
169		ret=NULL;
170		}
171	return(ret);
172	}
173
174void DH_free(DH *r)
175	{
176	int i;
177	if(r == NULL) return;
178	i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH);
179#ifdef REF_PRINT
180	REF_PRINT("DH",r);
181#endif
182	if (i > 0) return;
183#ifdef REF_CHECK
184	if (i < 0)
185		{
186		fprintf(stderr,"DH_free, bad reference count\n");
187		abort();
188	}
189#endif
190
191	if (r->meth->finish)
192		r->meth->finish(r);
193#ifndef OPENSSL_NO_ENGINE
194	if (r->engine)
195		ENGINE_finish(r->engine);
196#endif
197
198	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data);
199
200	if (r->p != NULL) BN_clear_free(r->p);
201	if (r->g != NULL) BN_clear_free(r->g);
202	if (r->q != NULL) BN_clear_free(r->q);
203	if (r->j != NULL) BN_clear_free(r->j);
204	if (r->seed) OPENSSL_free(r->seed);
205	if (r->counter != NULL) BN_clear_free(r->counter);
206	if (r->pub_key != NULL) BN_clear_free(r->pub_key);
207	if (r->priv_key != NULL) BN_clear_free(r->priv_key);
208	OPENSSL_free(r);
209	}
210
211int DH_up_ref(DH *r)
212	{
213	int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH);
214#ifdef REF_PRINT
215	REF_PRINT("DH",r);
216#endif
217#ifdef REF_CHECK
218	if (i < 2)
219		{
220		fprintf(stderr, "DH_up, bad reference count\n");
221		abort();
222		}
223#endif
224	return ((i > 1) ? 1 : 0);
225	}
226
227int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
228	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
229        {
230	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp,
231				new_func, dup_func, free_func);
232        }
233
234int DH_set_ex_data(DH *d, int idx, void *arg)
235	{
236	return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
237	}
238
239void *DH_get_ex_data(DH *d, int idx)
240	{
241	return(CRYPTO_get_ex_data(&d->ex_data,idx));
242	}
243
244int DH_size(const DH *dh)
245	{
246	return(BN_num_bytes(dh->p));
247	}
248