crypto/ec/ec_print.c

   1 /* ====================================================================
   2  * Copyright (c) 1998-2002 The OpenSSL Project.  All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  *
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in
  13  *    the documentation and/or other materials provided with the
  14  *    distribution.
  15  *
  16  * 3. All advertising materials mentioning features or use of this
  17  *    software must display the following acknowledgment:
  18  *    "This product includes software developed by the OpenSSL Project
  19  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  20  *
  21  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  22  *    endorse or promote products derived from this software without
  23  *    prior written permission. For written permission, please contact
  24  *    openssl-core@openssl.org.
  25  *
  26  * 5. Products derived from this software may not be called "OpenSSL"
  27  *    nor may "OpenSSL" appear in their names without prior written
  28  *    permission of the OpenSSL Project.
  29  *
  30  * 6. Redistributions of any form whatsoever must retain the following
  31  *    acknowledgment:
  32  *    "This product includes software developed by the OpenSSL Project
  33  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  34  *
  35  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  36  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  37  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  38  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  39  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  41  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  42  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  44  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  45  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  46  * OF THE POSSIBILITY OF SUCH DAMAGE.
  47  * ====================================================================
  48  *
  49  * This product includes cryptographic software written by Eric Young
  50  * (eay@cryptsoft.com).  This product includes software written by Tim
  51  * Hudson (tjh@cryptsoft.com).
  52  *
  53  */
  54
  55 #include <openssl/crypto.h>
  56 #include "ec_lcl.h"
  57
  58 BIGNUM *EC_POINT_point2bn(const EC_GROUP *group,
  59                           const EC_POINT *point,
  60                           point_conversion_form_t form,
  61                           BIGNUM *ret, BN_CTX *ctx)
  62 {
  63     size_t buf_len = 0;
  64     unsigned char *buf;
  65
  66     buf_len = EC_POINT_point2buf(group, point, form, &buf, ctx);
  67
  68     if (buf_len == 0)
  69         return NULL;
  70
  71     ret = BN_bin2bn(buf, buf_len, ret);
  72
  73     OPENSSL_free(buf);
  74
  75     return ret;
  76 }
  77
  78 EC_POINT *EC_POINT_bn2point(const EC_GROUP *group,
  79                             const BIGNUM *bn, EC_POINT *point, BN_CTX *ctx)
  80 {
  81     size_t buf_len = 0;
  82     unsigned char *buf;
  83     EC_POINT *ret;
  84
  85     if ((buf_len = BN_num_bytes(bn)) == 0)
  86         return NULL;
  87     buf = OPENSSL_malloc(buf_len);
  88     if (buf == NULL)
  89         return NULL;
  90
  91     if (!BN_bn2bin(bn, buf)) {
  92         OPENSSL_free(buf);
  93         return NULL;
  94     }
  95
  96     if (point == NULL) {
  97         if ((ret = EC_POINT_new(group)) == NULL) {
  98             OPENSSL_free(buf);
  99             return NULL;
 100         }
 101     } else
 102         ret = point;
 103
 104     if (!EC_POINT_oct2point(group, ret, buf, buf_len, ctx)) {
 105         if (ret != point)
 106             EC_POINT_clear_free(ret);
 107         OPENSSL_free(buf);
 108         return NULL;
 109     }
 110
 111     OPENSSL_free(buf);
 112     return ret;
 113 }
 114
 115 static const char *HEX_DIGITS = "0123456789ABCDEF";
 116
 117 /* the return value must be freed (using OPENSSL_free()) */
 118 char *EC_POINT_point2hex(const EC_GROUP *group,
 119                          const EC_POINT *point,
 120                          point_conversion_form_t form, BN_CTX *ctx)
 121 {
 122     char *ret, *p;
 123     size_t buf_len = 0, i;
 124     unsigned char *buf = NULL, *pbuf;
 125
 126     buf_len = EC_POINT_point2buf(group, point, form, &buf, ctx);
 127
 128     if (buf_len == 0)
 129         return NULL;
 130
 131     ret = OPENSSL_malloc(buf_len * 2 + 2);
 132     if (ret == NULL) {
 133         OPENSSL_free(buf);
 134         return NULL;
 135     }
 136     p = ret;
 137     pbuf = buf;
 138     for (i = buf_len; i > 0; i--) {
 139         int v = (int)*(pbuf++);
 140         *(p++) = HEX_DIGITS[v >> 4];
 141         *(p++) = HEX_DIGITS[v & 0x0F];
 142     }
 143     *p = '\0';
 144
 145     OPENSSL_free(buf);
 146
 147     return ret;
 148 }
 149
 150 EC_POINT *EC_POINT_hex2point(const EC_GROUP *group,
 151                              const char *buf, EC_POINT *point, BN_CTX *ctx)
 152 {
 153     EC_POINT *ret = NULL;
 154     BIGNUM *tmp_bn = NULL;
 155
 156     if (!BN_hex2bn(&tmp_bn, buf))
 157         return NULL;
 158
 159     ret = EC_POINT_bn2point(group, tmp_bn, point, ctx);
 160
 161     BN_clear_free(tmp_bn);
 162
 163     return ret;
 164 }