Change array representation of binary polynomials to make GF2m part of
[openssl.git] / crypto / ec / ec_print.c
1 /* crypto/ec/ec_print.c */
2 /* ====================================================================
3  * Copyright (c) 1998-2002 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
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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,
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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 <openssl/crypto.h>
57 #include "ec_lcl.h"
58
59 BIGNUM *EC_POINT_point2bn(const EC_GROUP *group, 
60                           const EC_POINT *point, 
61                           point_conversion_form_t form,
62                           BIGNUM *ret,
63                           BN_CTX *ctx)
64         {
65         size_t        buf_len=0;
66         unsigned char *buf;
67
68         buf_len = EC_POINT_point2oct(group, point, form,
69                                      NULL, 0, ctx);
70         if (buf_len == 0)
71                 return NULL;
72
73         if ((buf = OPENSSL_malloc(buf_len)) == NULL)
74                 return NULL;
75
76         if (!EC_POINT_point2oct(group, point, form, buf, buf_len, ctx))
77                 {
78                 OPENSSL_free(buf);
79                 return NULL;
80                 }
81
82         ret = BN_bin2bn(buf, buf_len, ret);
83
84         OPENSSL_free(buf);
85
86         return ret;
87 }
88
89 EC_POINT *EC_POINT_bn2point(const EC_GROUP *group,
90                             const BIGNUM *bn,
91                             EC_POINT *point, 
92                             BN_CTX *ctx)
93         {
94         size_t        buf_len=0;
95         unsigned char *buf;
96         EC_POINT      *ret;
97
98         if ((buf_len = BN_num_bytes(bn)) == 0) return NULL;
99         buf = OPENSSL_malloc(buf_len);
100         if (buf == NULL)
101                 return NULL;
102
103         if (!BN_bn2bin(bn, buf)) 
104                 {
105                 OPENSSL_free(buf);
106                 return NULL;
107                 }
108
109         if (point == NULL)
110                 {
111                 if ((ret = EC_POINT_new(group)) == NULL)
112                         {
113                         OPENSSL_free(buf);
114                         return NULL;
115                         }
116                 }
117         else
118                 ret = point;
119
120         if (!EC_POINT_oct2point(group, ret, buf, buf_len, ctx))
121                 {
122                 if (point == NULL)
123                         EC_POINT_clear_free(ret);
124                 OPENSSL_free(buf);
125                 return NULL;
126                 }
127
128         OPENSSL_free(buf);
129         return ret;
130         }
131
132 static const char *HEX_DIGITS = "0123456789ABCDEF";
133
134 /* the return value must be freed (using OPENSSL_free()) */
135 char *EC_POINT_point2hex(const EC_GROUP *group,
136                          const EC_POINT *point,
137                          point_conversion_form_t form,
138                          BN_CTX *ctx)
139         {
140         char          *ret, *p;
141         size_t        buf_len=0,i;
142         unsigned char *buf, *pbuf;
143
144         buf_len = EC_POINT_point2oct(group, point, form,
145                                      NULL, 0, ctx);
146         if (buf_len == 0)
147                 return NULL;
148
149         if ((buf = OPENSSL_malloc(buf_len)) == NULL)
150                 return NULL;
151
152         if (!EC_POINT_point2oct(group, point, form, buf, buf_len, ctx))
153                 {
154                 OPENSSL_free(buf);
155                 return NULL;
156                 }
157
158         ret = (char *)OPENSSL_malloc(buf_len*2+2);
159         if (ret == NULL)
160                 {
161                 OPENSSL_free(buf);
162                 return NULL;
163                 }
164         p = ret;
165         pbuf = buf;
166         for (i=buf_len; i > 0; i--)
167                 {
168                         int v = (int) *(pbuf++);
169                         *(p++)=HEX_DIGITS[v>>4];
170                         *(p++)=HEX_DIGITS[v&0x0F];
171                 }
172         *p='\0';
173
174         OPENSSL_free(buf);
175
176         return ret;
177         }
178
179 EC_POINT *EC_POINT_hex2point(const EC_GROUP *group,
180                              const char *buf,
181                              EC_POINT *point,
182                              BN_CTX *ctx)
183         {
184         EC_POINT *ret=NULL;
185         BIGNUM   *tmp_bn=NULL;
186
187         if (!BN_hex2bn(&tmp_bn, buf))
188                 return NULL;
189
190         ret = EC_POINT_bn2point(group, tmp_bn, point, ctx);
191
192         BN_clear_free(tmp_bn);
193
194         return ret;
195         }