ecs_lib.c revision 296465 
1/* crypto/ecdsa/ecs_lib.c */
2/* ====================================================================
3 * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in
14 *    the documentation and/or other materials provided with the
15 *    distribution.
16 *
17 * 3. All advertising materials mentioning features or use of this
18 *    software must display the following acknowledgment:
19 *    "This product includes software developed by the OpenSSL Project
20 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
21 *
22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
23 *    endorse or promote products derived from this software without
24 *    prior written permission. For written permission, please contact
25 *    openssl-core@OpenSSL.org.
26 *
27 * 5. Products derived from this software may not be called "OpenSSL"
28 *    nor may "OpenSSL" appear in their names without prior written
29 *    permission of the OpenSSL Project.
30 *
31 * 6. Redistributions of any form whatsoever must retain the following
32 *    acknowledgment:
33 *    "This product includes software developed by the OpenSSL Project
34 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
39 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
47 * OF THE POSSIBILITY OF SUCH DAMAGE.
48 * ====================================================================
49 *
50 * This product includes cryptographic software written by Eric Young
51 * (eay@cryptsoft.com).  This product includes software written by Tim
52 * Hudson (tjh@cryptsoft.com).
53 *
54 */
55
56#include <string.h>
57#include "ecs_locl.h"
58#ifndef OPENSSL_NO_ENGINE
59# include <openssl/engine.h>
60#endif
61#include <openssl/err.h>
62#include <openssl/bn.h>
63
64const char ECDSA_version[] = "ECDSA" OPENSSL_VERSION_PTEXT;
65
66static const ECDSA_METHOD *default_ECDSA_method = NULL;
67
68static void *ecdsa_data_new(void);
69static void *ecdsa_data_dup(void *);
70static void ecdsa_data_free(void *);
71
72void ECDSA_set_default_method(const ECDSA_METHOD *meth)
73{
74    default_ECDSA_method = meth;
75}
76
77const ECDSA_METHOD *ECDSA_get_default_method(void)
78{
79    if (!default_ECDSA_method)
80        default_ECDSA_method = ECDSA_OpenSSL();
81    return default_ECDSA_method;
82}
83
84int ECDSA_set_method(EC_KEY *eckey, const ECDSA_METHOD *meth)
85{
86    ECDSA_DATA *ecdsa;
87
88    ecdsa = ecdsa_check(eckey);
89
90    if (ecdsa == NULL)
91        return 0;
92
93#ifndef OPENSSL_NO_ENGINE
94    if (ecdsa->engine) {
95        ENGINE_finish(ecdsa->engine);
96        ecdsa->engine = NULL;
97    }
98#endif
99    ecdsa->meth = meth;
100
101    return 1;
102}
103
104static ECDSA_DATA *ECDSA_DATA_new_method(ENGINE *engine)
105{
106    ECDSA_DATA *ret;
107
108    ret = (ECDSA_DATA *)OPENSSL_malloc(sizeof(ECDSA_DATA));
109    if (ret == NULL) {
110        ECDSAerr(ECDSA_F_ECDSA_DATA_NEW_METHOD, ERR_R_MALLOC_FAILURE);
111        return (NULL);
112    }
113
114    ret->init = NULL;
115
116    ret->meth = ECDSA_get_default_method();
117    ret->engine = engine;
118#ifndef OPENSSL_NO_ENGINE
119    if (!ret->engine)
120        ret->engine = ENGINE_get_default_ECDSA();
121    if (ret->engine) {
122        ret->meth = ENGINE_get_ECDSA(ret->engine);
123        if (!ret->meth) {
124            ECDSAerr(ECDSA_F_ECDSA_DATA_NEW_METHOD, ERR_R_ENGINE_LIB);
125            ENGINE_finish(ret->engine);
126            OPENSSL_free(ret);
127            return NULL;
128        }
129    }
130#endif
131
132    ret->flags = ret->meth->flags;
133    CRYPTO_new_ex_data(CRYPTO_EX_INDEX_ECDSA, ret, &ret->ex_data);
134#if 0
135    if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
136        CRYPTO_free_ex_data(CRYPTO_EX_INDEX_ECDSA, ret, &ret->ex_data);
137        OPENSSL_free(ret);
138        ret = NULL;
139    }
140#endif
141    return (ret);
142}
143
144static void *ecdsa_data_new(void)
145{
146    return (void *)ECDSA_DATA_new_method(NULL);
147}
148
149static void *ecdsa_data_dup(void *data)
150{
151    ECDSA_DATA *r = (ECDSA_DATA *)data;
152
153    /* XXX: dummy operation */
154    if (r == NULL)
155        return NULL;
156
157    return ecdsa_data_new();
158}
159
160static void ecdsa_data_free(void *data)
161{
162    ECDSA_DATA *r = (ECDSA_DATA *)data;
163
164#ifndef OPENSSL_NO_ENGINE
165    if (r->engine)
166        ENGINE_finish(r->engine);
167#endif
168    CRYPTO_free_ex_data(CRYPTO_EX_INDEX_ECDSA, r, &r->ex_data);
169
170    OPENSSL_cleanse((void *)r, sizeof(ECDSA_DATA));
171
172    OPENSSL_free(r);
173}
174
175ECDSA_DATA *ecdsa_check(EC_KEY *key)
176{
177    ECDSA_DATA *ecdsa_data;
178
179    void *data = EC_KEY_get_key_method_data(key, ecdsa_data_dup,
180                                            ecdsa_data_free, ecdsa_data_free);
181    if (data == NULL) {
182        ecdsa_data = (ECDSA_DATA *)ecdsa_data_new();
183        if (ecdsa_data == NULL)
184            return NULL;
185        data = EC_KEY_insert_key_method_data(key, (void *)ecdsa_data,
186                                             ecdsa_data_dup, ecdsa_data_free,
187                                             ecdsa_data_free);
188        if (data != NULL) {
189            /*
190             * Another thread raced us to install the key_method data and
191             * won.
192             */
193            ecdsa_data_free(ecdsa_data);
194            ecdsa_data = (ECDSA_DATA *)data;
195        }
196    } else
197        ecdsa_data = (ECDSA_DATA *)data;
198
199    return ecdsa_data;
200}
201
202int ECDSA_size(const EC_KEY *r)
203{
204    int ret, i;
205    ASN1_INTEGER bs;
206    BIGNUM *order = NULL;
207    unsigned char buf[4];
208    const EC_GROUP *group;
209
210    if (r == NULL)
211        return 0;
212    group = EC_KEY_get0_group(r);
213    if (group == NULL)
214        return 0;
215
216    if ((order = BN_new()) == NULL)
217        return 0;
218    if (!EC_GROUP_get_order(group, order, NULL)) {
219        BN_clear_free(order);
220        return 0;
221    }
222    i = BN_num_bits(order);
223    bs.length = (i + 7) / 8;
224    bs.data = buf;
225    bs.type = V_ASN1_INTEGER;
226    /* If the top bit is set the asn1 encoding is 1 larger. */
227    buf[0] = 0xff;
228
229    i = i2d_ASN1_INTEGER(&bs, NULL);
230    i += i;                     /* r and s */
231    ret = ASN1_object_size(1, i, V_ASN1_SEQUENCE);
232    BN_clear_free(order);
233    return (ret);
234}
235
236int ECDSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
237                           CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
238{
239    return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_ECDSA, argl, argp,
240                                   new_func, dup_func, free_func);
241}
242
243int ECDSA_set_ex_data(EC_KEY *d, int idx, void *arg)
244{
245    ECDSA_DATA *ecdsa;
246    ecdsa = ecdsa_check(d);
247    if (ecdsa == NULL)
248        return 0;
249    return (CRYPTO_set_ex_data(&ecdsa->ex_data, idx, arg));
250}
251
252void *ECDSA_get_ex_data(EC_KEY *d, int idx)
253{
254    ECDSA_DATA *ecdsa;
255    ecdsa = ecdsa_check(d);
256    if (ecdsa == NULL)
257        return NULL;
258    return (CRYPTO_get_ex_data(&ecdsa->ex_data, idx));
259}
260