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 int EC_POINT_set_compressed_coordinates_GFp(const EC_GROUP *group,
  53                                             EC_POINT *point, const BIGNUM *x,
  54                                             int y_bit, BN_CTX *ctx)
  55 {
  56     return EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx);
  57 }
  58
  59 #ifndef OPENSSL_NO_EC2M
  60 int EC_POINT_set_compressed_coordinates_GF2m(const EC_GROUP *group,
  61                                              EC_POINT *point, const BIGNUM *x,
  62                                              int y_bit, BN_CTX *ctx)
  63 {
  64     return EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx);
  65 }
  66 #endif
  67
  68 size_t EC_POINT_point2oct(const EC_GROUP *group, const EC_POINT *point,
  69                           point_conversion_form_t form, unsigned char *buf,
  70                           size_t len, BN_CTX *ctx)
  71 {
  72     if (group->meth->point2oct == 0
  73         && !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
  74         ECerr(EC_F_EC_POINT_POINT2OCT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
  75         return 0;
  76     }
  77     if (!ec_point_is_compat(point, group)) {
  78         ECerr(EC_F_EC_POINT_POINT2OCT, EC_R_INCOMPATIBLE_OBJECTS);
  79         return 0;
  80     }
  81     if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
  82         if (group->meth->field_type == NID_X9_62_prime_field)
  83             return ec_GFp_simple_point2oct(group, point, form, buf, len, ctx);
  84         else
  85 #ifdef OPENSSL_NO_EC2M
  86         {
  87             ECerr(EC_F_EC_POINT_POINT2OCT, EC_R_GF2M_NOT_SUPPORTED);
  88             return 0;
  89         }
  90 #else
  91             return ec_GF2m_simple_point2oct(group, point,
  92                                             form, buf, len, ctx);
  93 #endif
  94     }
  95
  96     return group->meth->point2oct(group, point, form, buf, len, ctx);
  97 }
  98
  99 int EC_POINT_oct2point(const EC_GROUP *group, EC_POINT *point,
 100                        const unsigned char *buf, size_t len, BN_CTX *ctx)
 101 {
 102     if (group->meth->oct2point == 0
 103         && !(group->meth->flags & EC_FLAGS_DEFAULT_OCT)) {
 104         ECerr(EC_F_EC_POINT_OCT2POINT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 105         return 0;
 106     }
 107     if (!ec_point_is_compat(point, group)) {
 108         ECerr(EC_F_EC_POINT_OCT2POINT, EC_R_INCOMPATIBLE_OBJECTS);
 109         return 0;
 110     }
 111     if (group->meth->flags & EC_FLAGS_DEFAULT_OCT) {
 112         if (group->meth->field_type == NID_X9_62_prime_field)
 113             return ec_GFp_simple_oct2point(group, point, buf, len, ctx);
 114         else
 115 #ifdef OPENSSL_NO_EC2M
 116         {
 117             ECerr(EC_F_EC_POINT_OCT2POINT, EC_R_GF2M_NOT_SUPPORTED);
 118             return 0;
 119         }
 120 #else
 121             return ec_GF2m_simple_oct2point(group, point, buf, len, ctx);
 122 #endif
 123     }
 124     return group->meth->oct2point(group, point, buf, len, ctx);
 125 }
 126
 127 size_t EC_POINT_point2buf(const EC_GROUP *group, const EC_POINT *point,
 128                           point_conversion_form_t form,
 129                           unsigned char **pbuf, BN_CTX *ctx)
 130 {
 131     size_t len;
 132     unsigned char *buf;
 133
 134     len = EC_POINT_point2oct(group, point, form, NULL, 0, NULL);
 135     if (len == 0)
 136         return 0;
 137     if ((buf = OPENSSL_malloc(len)) == NULL) {
 138         ECerr(EC_F_EC_POINT_POINT2BUF, ERR_R_MALLOC_FAILURE);
 139         return 0;
 140     }
 141     len = EC_POINT_point2oct(group, point, form, buf, len, ctx);
 142     if (len == 0) {
 143         OPENSSL_free(buf);
 144         return 0;
 145     }
 146     *pbuf = buf;
 147     return len;
 148 }