1 /* $OpenBSD: dh_lib.c,v 1.37 2022/06/27 12:31:38 tb Exp $ */
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 <limits.h>
60 #include <stdio.h>
61
62 #include <openssl/opensslconf.h>
63
64 #include <openssl/bn.h>
65 #include <openssl/dh.h>
66 #include <openssl/err.h>
67
68 #ifndef OPENSSL_NO_ENGINE
69 #include <openssl/engine.h>
70 #endif
71
72 #include "dh_local.h"
73
74 static const DH_METHOD *default_DH_method = NULL;
75
76 void
DH_set_default_method(const DH_METHOD * meth)77 DH_set_default_method(const DH_METHOD *meth)
78 {
79 default_DH_method = meth;
80 }
81
82 const DH_METHOD *
DH_get_default_method(void)83 DH_get_default_method(void)
84 {
85 if (!default_DH_method)
86 default_DH_method = DH_OpenSSL();
87 return default_DH_method;
88 }
89
90 int
DH_set_method(DH * dh,const DH_METHOD * meth)91 DH_set_method(DH *dh, const DH_METHOD *meth)
92 {
93 /*
94 * NB: The caller is specifically setting a method, so it's not up to us
95 * to deal with which ENGINE it comes from.
96 */
97 const DH_METHOD *mtmp;
98
99 mtmp = dh->meth;
100 if (mtmp->finish)
101 mtmp->finish(dh);
102 #ifndef OPENSSL_NO_ENGINE
103 ENGINE_finish(dh->engine);
104 dh->engine = NULL;
105 #endif
106 dh->meth = meth;
107 if (meth->init)
108 meth->init(dh);
109 return 1;
110 }
111
112 DH *
DH_new(void)113 DH_new(void)
114 {
115 return DH_new_method(NULL);
116 }
117
118 DH *
DH_new_method(ENGINE * engine)119 DH_new_method(ENGINE *engine)
120 {
121 DH *ret;
122
123 ret = malloc(sizeof(DH));
124 if (ret == NULL) {
125 DHerror(ERR_R_MALLOC_FAILURE);
126 return NULL;
127 }
128
129 ret->meth = DH_get_default_method();
130 #ifndef OPENSSL_NO_ENGINE
131 if (engine) {
132 if (!ENGINE_init(engine)) {
133 DHerror(ERR_R_ENGINE_LIB);
134 free(ret);
135 return NULL;
136 }
137 ret->engine = engine;
138 } else
139 ret->engine = ENGINE_get_default_DH();
140 if(ret->engine) {
141 ret->meth = ENGINE_get_DH(ret->engine);
142 if (ret->meth == NULL) {
143 DHerror(ERR_R_ENGINE_LIB);
144 ENGINE_finish(ret->engine);
145 free(ret);
146 return NULL;
147 }
148 }
149 #endif
150
151 ret->pad = 0;
152 ret->version = 0;
153 ret->p = NULL;
154 ret->g = NULL;
155 ret->length = 0;
156 ret->pub_key = NULL;
157 ret->priv_key = NULL;
158 ret->q = NULL;
159 ret->j = NULL;
160 ret->seed = NULL;
161 ret->seedlen = 0;
162 ret->counter = NULL;
163 ret->method_mont_p=NULL;
164 ret->references = 1;
165 ret->flags = ret->meth->flags & ~DH_FLAG_NON_FIPS_ALLOW;
166 CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
167 if (ret->meth->init != NULL && !ret->meth->init(ret)) {
168 #ifndef OPENSSL_NO_ENGINE
169 ENGINE_finish(ret->engine);
170 #endif
171 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
172 free(ret);
173 ret = NULL;
174 }
175 return ret;
176 }
177
178 void
DH_free(DH * r)179 DH_free(DH *r)
180 {
181 int i;
182
183 if (r == NULL)
184 return;
185 i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH);
186 if (i > 0)
187 return;
188
189 if (r->meth->finish)
190 r->meth->finish(r);
191 #ifndef OPENSSL_NO_ENGINE
192 ENGINE_finish(r->engine);
193 #endif
194
195 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data);
196
197 BN_clear_free(r->p);
198 BN_clear_free(r->g);
199 BN_clear_free(r->q);
200 BN_clear_free(r->j);
201 free(r->seed);
202 BN_clear_free(r->counter);
203 BN_clear_free(r->pub_key);
204 BN_clear_free(r->priv_key);
205 free(r);
206 }
207
208 int
DH_up_ref(DH * r)209 DH_up_ref(DH *r)
210 {
211 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH);
212
213 return i > 1 ? 1 : 0;
214 }
215
216 int
DH_get_ex_new_index(long argl,void * argp,CRYPTO_EX_new * new_func,CRYPTO_EX_dup * dup_func,CRYPTO_EX_free * free_func)217 DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
218 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
219 {
220 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp, new_func,
221 dup_func, free_func);
222 }
223
224 int
DH_set_ex_data(DH * d,int idx,void * arg)225 DH_set_ex_data(DH *d, int idx, void *arg)
226 {
227 return CRYPTO_set_ex_data(&d->ex_data, idx, arg);
228 }
229
230 void *
DH_get_ex_data(DH * d,int idx)231 DH_get_ex_data(DH *d, int idx)
232 {
233 return CRYPTO_get_ex_data(&d->ex_data, idx);
234 }
235
236 int
DH_size(const DH * dh)237 DH_size(const DH *dh)
238 {
239 return BN_num_bytes(dh->p);
240 }
241
242 int
DH_bits(const DH * dh)243 DH_bits(const DH *dh)
244 {
245 return BN_num_bits(dh->p);
246 }
247
248 int
DH_security_bits(const DH * dh)249 DH_security_bits(const DH *dh)
250 {
251 int N = -1;
252
253 if (dh->q != NULL)
254 N = BN_num_bits(dh->q);
255 else if (dh->length > 0)
256 N = dh->length;
257
258 return BN_security_bits(BN_num_bits(dh->p), N);
259 }
260
261 ENGINE *
DH_get0_engine(DH * dh)262 DH_get0_engine(DH *dh)
263 {
264 return dh->engine;
265 }
266
267 void
DH_get0_pqg(const DH * dh,const BIGNUM ** p,const BIGNUM ** q,const BIGNUM ** g)268 DH_get0_pqg(const DH *dh, const BIGNUM **p, const BIGNUM **q, const BIGNUM **g)
269 {
270 if (p != NULL)
271 *p = dh->p;
272 if (q != NULL)
273 *q = dh->q;
274 if (g != NULL)
275 *g = dh->g;
276 }
277
278 int
DH_set0_pqg(DH * dh,BIGNUM * p,BIGNUM * q,BIGNUM * g)279 DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g)
280 {
281 if ((dh->p == NULL && p == NULL) || (dh->g == NULL && g == NULL))
282 return 0;
283
284 if (p != NULL) {
285 BN_free(dh->p);
286 dh->p = p;
287 }
288 if (q != NULL) {
289 BN_free(dh->q);
290 dh->q = q;
291 dh->length = BN_num_bits(dh->q);
292 }
293 if (g != NULL) {
294 BN_free(dh->g);
295 dh->g = g;
296 }
297
298 return 1;
299 }
300
301 void
DH_get0_key(const DH * dh,const BIGNUM ** pub_key,const BIGNUM ** priv_key)302 DH_get0_key(const DH *dh, const BIGNUM **pub_key, const BIGNUM **priv_key)
303 {
304 if (pub_key != NULL)
305 *pub_key = dh->pub_key;
306 if (priv_key != NULL)
307 *priv_key = dh->priv_key;
308 }
309
310 int
DH_set0_key(DH * dh,BIGNUM * pub_key,BIGNUM * priv_key)311 DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key)
312 {
313 if (pub_key != NULL) {
314 BN_free(dh->pub_key);
315 dh->pub_key = pub_key;
316 }
317 if (priv_key != NULL) {
318 BN_free(dh->priv_key);
319 dh->priv_key = priv_key;
320 }
321
322 return 1;
323 }
324
325 const BIGNUM *
DH_get0_p(const DH * dh)326 DH_get0_p(const DH *dh)
327 {
328 return dh->p;
329 }
330
331 const BIGNUM *
DH_get0_q(const DH * dh)332 DH_get0_q(const DH *dh)
333 {
334 return dh->q;
335 }
336
337 const BIGNUM *
DH_get0_g(const DH * dh)338 DH_get0_g(const DH *dh)
339 {
340 return dh->g;
341 }
342
343 const BIGNUM *
DH_get0_priv_key(const DH * dh)344 DH_get0_priv_key(const DH *dh)
345 {
346 return dh->priv_key;
347 }
348
349 const BIGNUM *
DH_get0_pub_key(const DH * dh)350 DH_get0_pub_key(const DH *dh)
351 {
352 return dh->pub_key;
353 }
354
355 void
DH_clear_flags(DH * dh,int flags)356 DH_clear_flags(DH *dh, int flags)
357 {
358 dh->flags &= ~flags;
359 }
360
361 int
DH_test_flags(const DH * dh,int flags)362 DH_test_flags(const DH *dh, int flags)
363 {
364 return dh->flags & flags;
365 }
366
367 void
DH_set_flags(DH * dh,int flags)368 DH_set_flags(DH *dh, int flags)
369 {
370 dh->flags |= flags;
371 }
372
373 long
DH_get_length(const DH * dh)374 DH_get_length(const DH *dh)
375 {
376 return dh->length;
377 }
378
379 int
DH_set_length(DH * dh,long length)380 DH_set_length(DH *dh, long length)
381 {
382 if (length < 0 || length > INT_MAX)
383 return 0;
384
385 dh->length = length;
386 return 1;
387 }
388