1 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
2  * project 2006.
3  */
4 /* ====================================================================
5  * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in
16  *    the documentation and/or other materials provided with the
17  *    distribution.
18  *
19  * 3. All advertising materials mentioning features or use of this
20  *    software must display the following acknowledgment:
21  *    "This product includes software developed by the OpenSSL Project
22  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
23  *
24  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
25  *    endorse or promote products derived from this software without
26  *    prior written permission. For written permission, please contact
27  *    licensing@OpenSSL.org.
28  *
29  * 5. Products derived from this software may not be called "OpenSSL"
30  *    nor may "OpenSSL" appear in their names without prior written
31  *    permission of the OpenSSL Project.
32  *
33  * 6. Redistributions of any form whatsoever must retain the following
34  *    acknowledgment:
35  *    "This product includes software developed by the OpenSSL Project
36  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
37  *
38  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
39  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
41  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
42  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
47  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
48  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
49  * OF THE POSSIBILITY OF SUCH DAMAGE.
50  * ====================================================================
51  *
52  * This product includes cryptographic software written by Eric Young
53  * (eay@cryptsoft.com).  This product includes software written by Tim
54  * Hudson (tjh@cryptsoft.com).
55  *
56  */
57 
58 #include <stdio.h>
59 #include "cryptlib.h"
60 #include <openssl/x509.h>
61 #include <openssl/asn1.h>
62 #include <openssl/dh.h>
63 #include <openssl/bn.h>
64 #include "asn1_locl.h"
65 
66 static void int_dh_free(EVP_PKEY *pkey)
67 	{
68 	DH_free(pkey->pkey.dh);
69 	}
70 
71 static int dh_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
72 	{
73 	const unsigned char *p, *pm;
74 	int pklen, pmlen;
75 	int ptype;
76 	void *pval;
77 	ASN1_STRING *pstr;
78 	X509_ALGOR *palg;
79 	ASN1_INTEGER *public_key = NULL;
80 
81 	DH *dh = NULL;
82 
83 	if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
84 		return 0;
85 	X509_ALGOR_get0(NULL, &ptype, &pval, palg);
86 
87 	if (ptype != V_ASN1_SEQUENCE)
88 		{
89 		DHerr(DH_F_DH_PUB_DECODE, DH_R_PARAMETER_ENCODING_ERROR);
90 		goto err;
91 		}
92 
93 	pstr = pval;
94 	pm = pstr->data;
95 	pmlen = pstr->length;
96 
97 	if (!(dh = d2i_DHparams(NULL, &pm, pmlen)))
98 		{
99 		DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
100 		goto err;
101 		}
102 
103 	if (!(public_key=d2i_ASN1_INTEGER(NULL, &p, pklen)))
104 		{
105 		DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
106 		goto err;
107 		}
108 
109 	/* We have parameters now set public key */
110 	if (!(dh->pub_key = ASN1_INTEGER_to_BN(public_key, NULL)))
111 		{
112 		DHerr(DH_F_DH_PUB_DECODE, DH_R_BN_DECODE_ERROR);
113 		goto err;
114 		}
115 
116 	ASN1_INTEGER_free(public_key);
117 	EVP_PKEY_assign_DH(pkey, dh);
118 	return 1;
119 
120 	err:
121 	if (public_key)
122 		ASN1_INTEGER_free(public_key);
123 	if (dh)
124 		DH_free(dh);
125 	return 0;
126 
127 	}
128 
129 static int dh_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
130 	{
131 	DH *dh;
132 	void *pval = NULL;
133 	int ptype;
134 	unsigned char *penc = NULL;
135 	int penclen;
136 	ASN1_STRING *str;
137 	ASN1_INTEGER *pub_key = NULL;
138 
139 	dh=pkey->pkey.dh;
140 
141 	str = ASN1_STRING_new();
142 	str->length = i2d_DHparams(dh, &str->data);
143 	if (str->length <= 0)
144 		{
145 		DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
146 		goto err;
147 		}
148 	pval = str;
149 	ptype = V_ASN1_SEQUENCE;
150 
151 	pub_key = BN_to_ASN1_INTEGER(dh->pub_key, NULL);
152 	if (!pub_key)
153 		goto err;
154 
155 	penclen = i2d_ASN1_INTEGER(pub_key, &penc);
156 
157 	ASN1_INTEGER_free(pub_key);
158 
159 	if (penclen <= 0)
160 		{
161 		DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
162 		goto err;
163 		}
164 
165 	if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_DH),
166 				ptype, pval, penc, penclen))
167 		return 1;
168 
169 	err:
170 	if (penc)
171 		OPENSSL_free(penc);
172 	if (pval)
173 		ASN1_STRING_free(pval);
174 
175 	return 0;
176 	}
177 
178 
179 /* PKCS#8 DH is defined in PKCS#11 of all places. It is similar to DH in
180  * that the AlgorithmIdentifier contains the paramaters, the private key
181  * is explcitly included and the pubkey must be recalculated.
182  */
183 
184 static int dh_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
185 	{
186 	const unsigned char *p, *pm;
187 	int pklen, pmlen;
188 	int ptype;
189 	void *pval;
190 	ASN1_STRING *pstr;
191 	X509_ALGOR *palg;
192 	ASN1_INTEGER *privkey = NULL;
193 
194 	DH *dh = NULL;
195 
196 	if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
197 		return 0;
198 
199 	X509_ALGOR_get0(NULL, &ptype, &pval, palg);
200 
201 	if (ptype != V_ASN1_SEQUENCE)
202 			goto decerr;
203 
204 	if (!(privkey=d2i_ASN1_INTEGER(NULL, &p, pklen)))
205 		goto decerr;
206 
207 
208 	pstr = pval;
209 	pm = pstr->data;
210 	pmlen = pstr->length;
211 	if (!(dh = d2i_DHparams(NULL, &pm, pmlen)))
212 		goto decerr;
213 	/* We have parameters now set private key */
214 	if (!(dh->priv_key = ASN1_INTEGER_to_BN(privkey, NULL)))
215 		{
216 		DHerr(DH_F_DH_PRIV_DECODE,DH_R_BN_ERROR);
217 		goto dherr;
218 		}
219 	/* Calculate public key */
220 	if (!DH_generate_key(dh))
221 		goto dherr;
222 
223 	EVP_PKEY_assign_DH(pkey, dh);
224 
225 	ASN1_INTEGER_free(privkey);
226 
227 	return 1;
228 
229 	decerr:
230 	DHerr(DH_F_DH_PRIV_DECODE, EVP_R_DECODE_ERROR);
231 	dherr:
232 	DH_free(dh);
233 	return 0;
234 	}
235 
236 static int dh_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
237 {
238 	ASN1_STRING *params = NULL;
239 	ASN1_INTEGER *prkey = NULL;
240 	unsigned char *dp = NULL;
241 	int dplen;
242 
243 	params = ASN1_STRING_new();
244 
245 	if (!params)
246 		{
247 		DHerr(DH_F_DH_PRIV_ENCODE,ERR_R_MALLOC_FAILURE);
248 		goto err;
249 		}
250 
251 	params->length = i2d_DHparams(pkey->pkey.dh, &params->data);
252 	if (params->length <= 0)
253 		{
254 		DHerr(DH_F_DH_PRIV_ENCODE,ERR_R_MALLOC_FAILURE);
255 		goto err;
256 		}
257 	params->type = V_ASN1_SEQUENCE;
258 
259 	/* Get private key into integer */
260 	prkey = BN_to_ASN1_INTEGER(pkey->pkey.dh->priv_key, NULL);
261 
262 	if (!prkey)
263 		{
264 		DHerr(DH_F_DH_PRIV_ENCODE,DH_R_BN_ERROR);
265 		goto err;
266 		}
267 
268 	dplen = i2d_ASN1_INTEGER(prkey, &dp);
269 
270 	ASN1_INTEGER_free(prkey);
271 
272 	if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_dhKeyAgreement), 0,
273 				V_ASN1_SEQUENCE, params, dp, dplen))
274 		goto err;
275 
276 	return 1;
277 
278 err:
279 	if (dp != NULL)
280 		OPENSSL_free(dp);
281 	if (params != NULL)
282 		ASN1_STRING_free(params);
283 	if (prkey != NULL)
284 		ASN1_INTEGER_free(prkey);
285 	return 0;
286 }
287 
288 
289 static void update_buflen(const BIGNUM *b, size_t *pbuflen)
290 	{
291 	size_t i;
292 	if (!b)
293 		return;
294 	if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
295 			*pbuflen = i;
296 	}
297 
298 static int dh_param_decode(EVP_PKEY *pkey,
299 					const unsigned char **pder, int derlen)
300 	{
301 	DH *dh;
302 	if (!(dh = d2i_DHparams(NULL, pder, derlen)))
303 		{
304 		DHerr(DH_F_DH_PARAM_DECODE, ERR_R_DH_LIB);
305 		return 0;
306 		}
307 	EVP_PKEY_assign_DH(pkey, dh);
308 	return 1;
309 	}
310 
311 static int dh_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
312 	{
313 	return i2d_DHparams(pkey->pkey.dh, pder);
314 	}
315 
316 static int do_dh_print(BIO *bp, const DH *x, int indent,
317 						ASN1_PCTX *ctx, int ptype)
318 	{
319 	unsigned char *m=NULL;
320 	int reason=ERR_R_BUF_LIB,ret=0;
321 	size_t buf_len=0;
322 
323 	const char *ktype = NULL;
324 
325 	BIGNUM *priv_key, *pub_key;
326 
327 	if (ptype == 2)
328 		priv_key = x->priv_key;
329 	else
330 		priv_key = NULL;
331 
332 	if (ptype > 0)
333 		pub_key = x->pub_key;
334 	else
335 		pub_key = NULL;
336 
337 	update_buflen(x->p, &buf_len);
338 
339 	if (buf_len == 0)
340 		{
341 		reason = ERR_R_PASSED_NULL_PARAMETER;
342 		goto err;
343 		}
344 
345 	update_buflen(x->g, &buf_len);
346 	update_buflen(pub_key, &buf_len);
347 	update_buflen(priv_key, &buf_len);
348 
349 	if (ptype == 2)
350 		ktype = "PKCS#3 DH Private-Key";
351 	else if (ptype == 1)
352 		ktype = "PKCS#3 DH Public-Key";
353 	else
354 		ktype = "PKCS#3 DH Parameters";
355 
356 	m= OPENSSL_malloc(buf_len+10);
357 	if (m == NULL)
358 		{
359 		reason=ERR_R_MALLOC_FAILURE;
360 		goto err;
361 		}
362 
363 	BIO_indent(bp, indent, 128);
364 	if (BIO_printf(bp,"%s: (%d bit)\n", ktype, BN_num_bits(x->p)) <= 0)
365 		goto err;
366 	indent += 4;
367 
368 	if (!ASN1_bn_print(bp,"private-key:",priv_key,m,indent)) goto err;
369 	if (!ASN1_bn_print(bp,"public-key:",pub_key,m,indent)) goto err;
370 
371 	if (!ASN1_bn_print(bp,"prime:",x->p,m,indent)) goto err;
372 	if (!ASN1_bn_print(bp,"generator:",x->g,m,indent)) goto err;
373 	if (x->length != 0)
374 		{
375 		BIO_indent(bp, indent, 128);
376 		if (BIO_printf(bp,"recommended-private-length: %d bits\n",
377 			(int)x->length) <= 0) goto err;
378 		}
379 
380 
381 	ret=1;
382 	if (0)
383 		{
384 err:
385 		DHerr(DH_F_DO_DH_PRINT,reason);
386 		}
387 	if (m != NULL) OPENSSL_free(m);
388 	return(ret);
389 	}
390 
391 static int int_dh_size(const EVP_PKEY *pkey)
392 	{
393 	return(DH_size(pkey->pkey.dh));
394 	}
395 
396 static int dh_bits(const EVP_PKEY *pkey)
397 	{
398 	return BN_num_bits(pkey->pkey.dh->p);
399 	}
400 
401 static int dh_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
402 	{
403 	if (	BN_cmp(a->pkey.dh->p,b->pkey.dh->p) ||
404 		BN_cmp(a->pkey.dh->g,b->pkey.dh->g))
405 		return 0;
406 	else
407 		return 1;
408 	}
409 
410 static int dh_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
411 	{
412 	BIGNUM *a;
413 
414 	if ((a=BN_dup(from->pkey.dh->p)) == NULL)
415 		return 0;
416 	if (to->pkey.dh->p != NULL)
417 		BN_free(to->pkey.dh->p);
418 	to->pkey.dh->p=a;
419 
420 	if ((a=BN_dup(from->pkey.dh->g)) == NULL)
421 		return 0;
422 	if (to->pkey.dh->g != NULL)
423 		BN_free(to->pkey.dh->g);
424 	to->pkey.dh->g=a;
425 
426 	return 1;
427 	}
428 
429 static int dh_missing_parameters(const EVP_PKEY *a)
430 	{
431 	if (!a->pkey.dh->p || !a->pkey.dh->g)
432 		return 1;
433 	return 0;
434 	}
435 
436 static int dh_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
437 	{
438 	if (dh_cmp_parameters(a, b) == 0)
439 		return 0;
440 	if (BN_cmp(b->pkey.dh->pub_key,a->pkey.dh->pub_key) != 0)
441 		return 0;
442 	else
443 		return 1;
444 	}
445 
446 static int dh_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
447 							ASN1_PCTX *ctx)
448 	{
449 	return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 0);
450 	}
451 
452 static int dh_public_print(BIO *bp, const EVP_PKEY *pkey, int indent,
453 							ASN1_PCTX *ctx)
454 	{
455 	return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 1);
456 	}
457 
458 static int dh_private_print(BIO *bp, const EVP_PKEY *pkey, int indent,
459 							ASN1_PCTX *ctx)
460 	{
461 	return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 2);
462 	}
463 
464 int DHparams_print(BIO *bp, const DH *x)
465 	{
466 	return do_dh_print(bp, x, 4, NULL, 0);
467 	}
468 
469 const EVP_PKEY_ASN1_METHOD dh_asn1_meth =
470 	{
471 	EVP_PKEY_DH,
472 	EVP_PKEY_DH,
473 	0,
474 
475 	"DH",
476 	"OpenSSL PKCS#3 DH method",
477 
478 	dh_pub_decode,
479 	dh_pub_encode,
480 	dh_pub_cmp,
481 	dh_public_print,
482 
483 	dh_priv_decode,
484 	dh_priv_encode,
485 	dh_private_print,
486 
487 	int_dh_size,
488 	dh_bits,
489 
490 	dh_param_decode,
491 	dh_param_encode,
492 	dh_missing_parameters,
493 	dh_copy_parameters,
494 	dh_cmp_parameters,
495 	dh_param_print,
496 	0,
497 
498 	int_dh_free,
499 	0
500 	};
501 
502