crypto/ec/ec_oct.c

   1 /*
   2  * Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
   4  *
   5  * Licensed under the OpenSSL license (the "License").  You may not use
   6  * this file except in compliance with the License.  You can obtain a copy
   7  * in the file LICENSE in the source distribution or at
   8  * https://www.openssl.org/source/license.html
   9  */
  10
  11 #include <string.h>
  12
  13 #include <openssl/err.h>
  14 #include <openssl/opensslv.h>
  15
  16 #include "ec_lcl.h"
  17
  18 int EC_POINT_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point,
  19                                         const BIGNUM *x, int y_bit, BN_CTX *ctx)
  20 {
  21     if (group->meth->point_set_compressed_coordinates == NULL
  22         && !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
  23         ECerr(EC_F_EC_POINT_SET_COMPRESSED_COORDINATES,
  24               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
  25         return 0;
  26     }
  27     if (!ec_point_is_compat(point, group)) {
  28         ECerr(EC_F_EC_POINT_SET_COMPRESSED_COORDINATES,
  29               EC_R_INCOMPATIBLE_OBJECTS);
  30         return 0;
  31     }
  32     if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
  33         if (group->meth->field_type == NID_X9_62_prime_field)
  34             return ec_GFp_simple_set_compressed_coordinates(group, point, x,
  35                                                             y_bit, ctx);
  36         else
  37 #ifdef OPENSSL_NO_EC2M
  38         {
  39             ECerr(EC_F_EC_POINT_SET_COMPRESSED_COORDINATES,
  40                   EC_R_GF2M_NOT_SUPPORTED);
  41             return 0;
  42         }
  43 #else
  44             return ec_GF2m_simple_set_compressed_coordinates(group, point, x,
  45                                                              y_bit, ctx);
  46 #endif
  47     }
  48     return group->meth->point_set_compressed_coordinates(group, point, x,
  49                                                          y_bit, ctx);
  50 }
  51
  52 #if OPENSSL_API_COMPAT < 0x10200000L
  53 int EC_POINT_set_compressed_coordinates_GFp(const EC_GROUP *group,
  54                                             EC_POINT *point, const BIGNUM *x,
  55                                             int y_bit, BN_CTX *ctx)
  56 {
  57     return EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx);
  58 }
  59
  60 # ifndef OPENSSL_NO_EC2M
  61 int EC_POINT_set_compressed_coordinates_GF2m(const EC_GROUP *group,
  62                                              EC_POINT *point, const BIGNUM *x,
  63                                              int y_bit, BN_CTX *ctx)
  64 {
  65     return EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx);
  66 }
  67 # endif
  68 #endif
  69
  70 size_t EC_POINT_point2oct(const EC_GROUP *group, const EC_POINT *point,
  71                           point_conversion_form_t form, unsigned char *buf,
  72                           size_t len, BN_CTX *ctx)
  73 {
  74     if (group->meth->point2oct == 0
  75         && !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
  76         ECerr(EC_F_EC_POINT_POINT2OCT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
  77         return 0;
  78     }
  79     if (!ec_point_is_compat(point, group)) {
  80         ECerr(EC_F_EC_POINT_POINT2OCT, EC_R_INCOMPATIBLE_OBJECTS);
  81         return 0;
  82     }
  83     if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
  84         if (group->meth->field_type == NID_X9_62_prime_field)
  85             return ec_GFp_simple_point2oct(group, point, form, buf, len, ctx);
  86         else
  87 #ifdef OPENSSL_NO_EC2M
  88         {
  89             ECerr(EC_F_EC_POINT_POINT2OCT, EC_R_GF2M_NOT_SUPPORTED);
  90             return 0;
  91         }
  92 #else
  93             return ec_GF2m_simple_point2oct(group, point,
  94                                             form, buf, len, ctx);
  95 #endif
  96     }
  97
  98     return group->meth->point2oct(group, point, form, buf, len, ctx);
  99 }
 100
 101 int EC_POINT_oct2point(const EC_GROUP *group, EC_POINT *point,
 102                        const unsigned char *buf, size_t len, BN_CTX *ctx)
 103 {
 104     if (group->meth->oct2point == 0
 105         && !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
 106         ECerr(EC_F_EC_POINT_OCT2POINT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 107         return 0;
 108     }
 109     if (!ec_point_is_compat(point, group)) {
 110         ECerr(EC_F_EC_POINT_OCT2POINT, EC_R_INCOMPATIBLE_OBJECTS);
 111         return 0;
 112     }
 113     if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
 114         if (group->meth->field_type == NID_X9_62_prime_field)
 115             return ec_GFp_simple_oct2point(group, point, buf, len, ctx);
 116         else
 117 #ifdef OPENSSL_NO_EC2M
 118         {
 119             ECerr(EC_F_EC_POINT_OCT2POINT, EC_R_GF2M_NOT_SUPPORTED);
 120             return 0;
 121         }
 122 #else
 123             return ec_GF2m_simple_oct2point(group, point, buf, len, ctx);
 124 #endif
 125     }
 126     return group->meth->oct2point(group, point, buf, len, ctx);
 127 }
 128
 129 size_t EC_POINT_point2buf(const EC_GROUP *group, const EC_POINT *point,
 130                           point_conversion_form_t form,
 131                           unsigned char **pbuf, BN_CTX *ctx)
 132 {
 133     size_t len;
 134     unsigned char *buf;
 135
 136     len = EC_POINT_point2oct(group, point, form, NULL, 0, NULL);
 137     if (len == 0)
 138         return 0;
 139     if ((buf = OPENSSL_malloc(len)) == NULL) {
 140         ECerr(EC_F_EC_POINT_POINT2BUF, ERR_R_MALLOC_FAILURE);
 141         return 0;
 142     }
 143     len = EC_POINT_point2oct(group, point, form, buf, len, ctx);
 144     if (len == 0) {
 145         OPENSSL_free(buf);
 146         return 0;
 147     }
 148     *pbuf = buf;
 149     return len;
 150 }