1/* crypto/ec/ec_key.c */
2/*
3 * Written by Nils Larsch for the OpenSSL project.
4 */
5/* ====================================================================
6 * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 *    software must display the following acknowledgment:
22 *    "This product includes software developed by the OpenSSL Project
23 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 *    endorse or promote products derived from this software without
27 *    prior written permission. For written permission, please contact
28 *    openssl-core@openssl.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 *    nor may "OpenSSL" appear in their names without prior written
32 *    permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58/* ====================================================================
59 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
60 * Portions originally developed by SUN MICROSYSTEMS, INC., and
61 * contributed to the OpenSSL project.
62 */
63
64#include <string.h>
65#include "ec_lcl.h"
66#include <openssl/err.h>
67#ifdef OPENSSL_FIPS
68#include <openssl/fips.h>
69#endif
70
71EC_KEY *EC_KEY_new(void)
72	{
73	EC_KEY *ret;
74
75	ret=(EC_KEY *)OPENSSL_malloc(sizeof(EC_KEY));
76	if (ret == NULL)
77		{
78		ECerr(EC_F_EC_KEY_NEW, ERR_R_MALLOC_FAILURE);
79		return(NULL);
80		}
81
82	ret->version = 1;
83	ret->flags = 0;
84	ret->group   = NULL;
85	ret->pub_key = NULL;
86	ret->priv_key= NULL;
87	ret->enc_flag= 0;
88	ret->nonce_from_hash_flag = 0;
89	ret->conv_form = POINT_CONVERSION_UNCOMPRESSED;
90	ret->references= 1;
91	ret->method_data = NULL;
92	return(ret);
93	}
94
95EC_KEY *EC_KEY_new_by_curve_name(int nid)
96	{
97	EC_KEY *ret = EC_KEY_new();
98	if (ret == NULL)
99		return NULL;
100	ret->group = EC_GROUP_new_by_curve_name(nid);
101	if (ret->group == NULL)
102		{
103		EC_KEY_free(ret);
104		return NULL;
105		}
106	return ret;
107	}
108
109void EC_KEY_free(EC_KEY *r)
110	{
111	int i;
112
113	if (r == NULL) return;
114
115	i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_EC);
116#ifdef REF_PRINT
117	REF_PRINT("EC_KEY",r);
118#endif
119	if (i > 0) return;
120#ifdef REF_CHECK
121	if (i < 0)
122		{
123		fprintf(stderr,"EC_KEY_free, bad reference count\n");
124		abort();
125		}
126#endif
127
128	if (r->group    != NULL)
129		EC_GROUP_free(r->group);
130	if (r->pub_key  != NULL)
131		EC_POINT_free(r->pub_key);
132	if (r->priv_key != NULL)
133		BN_clear_free(r->priv_key);
134
135	EC_EX_DATA_free_all_data(&r->method_data);
136
137	OPENSSL_cleanse((void *)r, sizeof(EC_KEY));
138
139	OPENSSL_free(r);
140	}
141
142EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src)
143	{
144	EC_EXTRA_DATA *d;
145
146	if (dest == NULL || src == NULL)
147		{
148		ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER);
149		return NULL;
150		}
151	/* copy the parameters */
152	if (src->group)
153		{
154		const EC_METHOD *meth = EC_GROUP_method_of(src->group);
155		/* clear the old group */
156		if (dest->group)
157			EC_GROUP_free(dest->group);
158		dest->group = EC_GROUP_new(meth);
159		if (dest->group == NULL)
160			return NULL;
161		if (!EC_GROUP_copy(dest->group, src->group))
162			return NULL;
163		}
164	/*  copy the public key */
165	if (src->pub_key && src->group)
166		{
167		if (dest->pub_key)
168			EC_POINT_free(dest->pub_key);
169		dest->pub_key = EC_POINT_new(src->group);
170		if (dest->pub_key == NULL)
171			return NULL;
172		if (!EC_POINT_copy(dest->pub_key, src->pub_key))
173			return NULL;
174		}
175	/* copy the private key */
176	if (src->priv_key)
177		{
178		if (dest->priv_key == NULL)
179			{
180			dest->priv_key = BN_new();
181			if (dest->priv_key == NULL)
182				return NULL;
183			}
184		if (!BN_copy(dest->priv_key, src->priv_key))
185			return NULL;
186		}
187	/* copy method/extra data */
188	EC_EX_DATA_free_all_data(&dest->method_data);
189
190	for (d = src->method_data; d != NULL; d = d->next)
191		{
192		void *t = d->dup_func(d->data);
193
194		if (t == NULL)
195			return 0;
196		if (!EC_EX_DATA_set_data(&dest->method_data, t, d->dup_func, d->free_func, d->clear_free_func))
197			return 0;
198		}
199
200	/* copy the rest */
201	dest->enc_flag  = src->enc_flag;
202	dest->nonce_from_hash_flag = src->nonce_from_hash_flag;
203	dest->conv_form = src->conv_form;
204	dest->version   = src->version;
205	dest->flags = src->flags;
206
207	return dest;
208	}
209
210EC_KEY *EC_KEY_dup(const EC_KEY *ec_key)
211	{
212	EC_KEY *ret = EC_KEY_new();
213	if (ret == NULL)
214		return NULL;
215	if (EC_KEY_copy(ret, ec_key) == NULL)
216		{
217		EC_KEY_free(ret);
218		return NULL;
219		}
220	return ret;
221	}
222
223int EC_KEY_up_ref(EC_KEY *r)
224	{
225	int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_EC);
226#ifdef REF_PRINT
227	REF_PRINT("EC_KEY",r);
228#endif
229#ifdef REF_CHECK
230	if (i < 2)
231		{
232		fprintf(stderr, "EC_KEY_up, bad reference count\n");
233		abort();
234		}
235#endif
236	return ((i > 1) ? 1 : 0);
237	}
238
239int EC_KEY_generate_key(EC_KEY *eckey)
240	{
241	int	ok = 0;
242	BN_CTX	*ctx = NULL;
243	BIGNUM	*priv_key = NULL, *order = NULL;
244	EC_POINT *pub_key = NULL;
245
246#ifdef OPENSSL_FIPS
247	if (FIPS_mode())
248		return FIPS_ec_key_generate_key(eckey);
249#endif
250
251	if (!eckey || !eckey->group)
252		{
253		ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER);
254		return 0;
255		}
256
257	if ((order = BN_new()) == NULL) goto err;
258	if ((ctx = BN_CTX_new()) == NULL) goto err;
259
260	if (eckey->priv_key == NULL)
261		{
262		priv_key = BN_new();
263		if (priv_key == NULL)
264			goto err;
265		}
266	else
267		priv_key = eckey->priv_key;
268
269	if (!EC_GROUP_get_order(eckey->group, order, ctx))
270		goto err;
271
272	do
273		if (!BN_rand_range(priv_key, order))
274			goto err;
275	while (BN_is_zero(priv_key));
276
277	if (eckey->pub_key == NULL)
278		{
279		pub_key = EC_POINT_new(eckey->group);
280		if (pub_key == NULL)
281			goto err;
282		}
283	else
284		pub_key = eckey->pub_key;
285
286	if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx))
287		goto err;
288
289	eckey->priv_key = priv_key;
290	eckey->pub_key  = pub_key;
291
292	ok=1;
293
294err:
295	if (order)
296		BN_free(order);
297	if (pub_key  != NULL && eckey->pub_key  == NULL)
298		EC_POINT_free(pub_key);
299	if (priv_key != NULL && eckey->priv_key == NULL)
300		BN_free(priv_key);
301	if (ctx != NULL)
302		BN_CTX_free(ctx);
303	return(ok);
304	}
305
306int EC_KEY_check_key(const EC_KEY *eckey)
307	{
308	int	ok   = 0;
309	BN_CTX	*ctx = NULL;
310	const BIGNUM	*order  = NULL;
311	EC_POINT *point = NULL;
312
313	if (!eckey || !eckey->group || !eckey->pub_key)
314		{
315		ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_PASSED_NULL_PARAMETER);
316		return 0;
317		}
318
319	if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key))
320		{
321		ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_AT_INFINITY);
322		goto err;
323		}
324
325	if ((ctx = BN_CTX_new()) == NULL)
326		goto err;
327	if ((point = EC_POINT_new(eckey->group)) == NULL)
328		goto err;
329
330	/* testing whether the pub_key is on the elliptic curve */
331	if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx))
332		{
333		ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_IS_NOT_ON_CURVE);
334		goto err;
335		}
336	/* testing whether pub_key * order is the point at infinity */
337	order = &eckey->group->order;
338	if (BN_is_zero(order))
339		{
340		ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_GROUP_ORDER);
341		goto err;
342		}
343	if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx))
344		{
345		ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB);
346		goto err;
347		}
348	if (!EC_POINT_is_at_infinity(eckey->group, point))
349		{
350		ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER);
351		goto err;
352		}
353	/* in case the priv_key is present :
354	 * check if generator * priv_key == pub_key
355	 */
356	if (eckey->priv_key)
357		{
358		if (BN_cmp(eckey->priv_key, order) >= 0)
359			{
360			ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER);
361			goto err;
362			}
363		if (!EC_POINT_mul(eckey->group, point, eckey->priv_key,
364			NULL, NULL, ctx))
365			{
366			ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB);
367			goto err;
368			}
369		if (EC_POINT_cmp(eckey->group, point, eckey->pub_key,
370			ctx) != 0)
371			{
372			ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_PRIVATE_KEY);
373			goto err;
374			}
375		}
376	ok = 1;
377err:
378	if (ctx   != NULL)
379		BN_CTX_free(ctx);
380	if (point != NULL)
381		EC_POINT_free(point);
382	return(ok);
383	}
384
385int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, BIGNUM *y)
386	{
387	BN_CTX *ctx = NULL;
388	BIGNUM *tx, *ty;
389	EC_POINT *point = NULL;
390	int ok = 0, tmp_nid, is_char_two = 0;
391
392	if (!key || !key->group || !x || !y)
393		{
394		ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES,
395						ERR_R_PASSED_NULL_PARAMETER);
396		return 0;
397		}
398	ctx = BN_CTX_new();
399	if (!ctx)
400		goto err;
401
402	point = EC_POINT_new(key->group);
403
404	if (!point)
405		goto err;
406
407	tmp_nid = EC_METHOD_get_field_type(EC_GROUP_method_of(key->group));
408
409        if (tmp_nid == NID_X9_62_characteristic_two_field)
410		is_char_two = 1;
411
412	tx = BN_CTX_get(ctx);
413	ty = BN_CTX_get(ctx);
414#ifndef OPENSSL_NO_EC2M
415	if (is_char_two)
416		{
417		if (!EC_POINT_set_affine_coordinates_GF2m(key->group, point,
418								x, y, ctx))
419			goto err;
420		if (!EC_POINT_get_affine_coordinates_GF2m(key->group, point,
421								tx, ty, ctx))
422			goto err;
423		}
424	else
425#endif
426		{
427		if (!EC_POINT_set_affine_coordinates_GFp(key->group, point,
428								x, y, ctx))
429			goto err;
430		if (!EC_POINT_get_affine_coordinates_GFp(key->group, point,
431								tx, ty, ctx))
432			goto err;
433		}
434	/* Check if retrieved coordinates match originals: if not values
435	 * are out of range.
436	 */
437	if (BN_cmp(x, tx) || BN_cmp(y, ty))
438		{
439		ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES,
440			EC_R_COORDINATES_OUT_OF_RANGE);
441		goto err;
442		}
443
444	if (!EC_KEY_set_public_key(key, point))
445		goto err;
446
447	if (EC_KEY_check_key(key) == 0)
448		goto err;
449
450	ok = 1;
451
452	err:
453	if (ctx)
454		BN_CTX_free(ctx);
455	if (point)
456		EC_POINT_free(point);
457	return ok;
458
459	}
460
461const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key)
462	{
463	return key->group;
464	}
465
466int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group)
467	{
468	if (key->group != NULL)
469		EC_GROUP_free(key->group);
470	key->group = EC_GROUP_dup(group);
471	return (key->group == NULL) ? 0 : 1;
472	}
473
474const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key)
475	{
476	return key->priv_key;
477	}
478
479int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key)
480	{
481	if (key->priv_key)
482		BN_clear_free(key->priv_key);
483	key->priv_key = BN_dup(priv_key);
484	return (key->priv_key == NULL) ? 0 : 1;
485	}
486
487const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key)
488	{
489	return key->pub_key;
490	}
491
492int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key)
493	{
494	if (key->pub_key != NULL)
495		EC_POINT_free(key->pub_key);
496	key->pub_key = EC_POINT_dup(pub_key, key->group);
497	return (key->pub_key == NULL) ? 0 : 1;
498	}
499
500unsigned int EC_KEY_get_enc_flags(const EC_KEY *key)
501	{
502	return key->enc_flag;
503	}
504
505void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags)
506	{
507	key->enc_flag = flags;
508	}
509
510int EC_KEY_get_nonce_from_hash(const EC_KEY *key)
511	{
512	return key->nonce_from_hash_flag;
513	}
514
515void EC_KEY_set_nonce_from_hash(EC_KEY *key, int on)
516	{
517	key->nonce_from_hash_flag = on != 0;
518	}
519
520point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key)
521	{
522	return key->conv_form;
523	}
524
525void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform)
526	{
527	key->conv_form = cform;
528	if (key->group != NULL)
529		EC_GROUP_set_point_conversion_form(key->group, cform);
530	}
531
532void *EC_KEY_get_key_method_data(EC_KEY *key,
533	void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *))
534	{
535	void *ret;
536
537	CRYPTO_r_lock(CRYPTO_LOCK_EC);
538	ret = EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func);
539	CRYPTO_r_unlock(CRYPTO_LOCK_EC);
540
541	return ret;
542	}
543
544void *EC_KEY_insert_key_method_data(EC_KEY *key, void *data,
545	void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *))
546	{
547	EC_EXTRA_DATA *ex_data;
548
549	CRYPTO_w_lock(CRYPTO_LOCK_EC);
550	ex_data = EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func);
551	if (ex_data == NULL)
552		EC_EX_DATA_set_data(&key->method_data, data, dup_func, free_func, clear_free_func);
553	CRYPTO_w_unlock(CRYPTO_LOCK_EC);
554
555	return ex_data;
556	}
557
558void EC_KEY_set_asn1_flag(EC_KEY *key, int flag)
559	{
560	if (key->group != NULL)
561		EC_GROUP_set_asn1_flag(key->group, flag);
562	}
563
564int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx)
565	{
566	if (key->group == NULL)
567		return 0;
568	return EC_GROUP_precompute_mult(key->group, ctx);
569	}
570
571int EC_KEY_get_flags(const EC_KEY *key)
572	{
573	return key->flags;
574	}
575
576void EC_KEY_set_flags(EC_KEY *key, int flags)
577	{
578	key->flags |= flags;
579	}
580
581void EC_KEY_clear_flags(EC_KEY *key, int flags)
582	{
583	key->flags &= ~flags;
584	}
585