lib/gnutls_num.c

   1 /*
   2  * Copyright (C) 2000-2012 Free Software Foundation, Inc.
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GnuTLS.
   7  *
   8  * The GnuTLS is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 3 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>
  20  *
  21  */
  22
  23 /* This file contains the functions needed for 64 bit integer support in
  24  * TLS, and functions which ease the access to TLS vectors (data of given size).
  25  */
  26
  27 #include <gnutls_int.h>
  28 #include <gnutls_num.h>
  29 #include <gnutls_errors.h>
  30
  31 #include <byteswap.h>
  32
  33 /* This function will add one to uint64 x.
  34  * Returns 0 on success, or -1 if the uint64 max limit
  35  * has been reached.
  36  */
  37 int
  38 _gnutls_uint64pp (uint64 * x)
  39 {
  40   register int i, y = 0;
  41
  42   for (i = 7; i >= 0; i--)
  43     {
  44       y = 0;
  45       if (x->i[i] == 0xff)
  46         {
  47           x->i[i] = 0;
  48           y = 1;
  49         }
  50       else
  51         x->i[i]++;
  52
  53       if (y == 0)
  54         break;
  55     }
  56   if (y != 0)
  57     return -1;                  /* over 64 bits! WOW */
  58
  59   return 0;
  60 }
  61
  62 /* This function will add one to uint48 x.
  63  * Returns 0 on success, or -1 if the uint48 max limit
  64  * has been reached.
  65  */
  66 int
  67 _gnutls_uint48pp (uint64 * x)
  68 {
  69   register int i, y = 0;
  70
  71   for (i = 7; i >= 3; i--)
  72     {
  73       y = 0;
  74       if (x->i[i] == 0xff)
  75         {
  76           x->i[i] = 0;
  77           y = 1;
  78         }
  79       else
  80         x->i[i]++;
  81
  82       if (y == 0)
  83         break;
  84     }
  85   if (y != 0)
  86     return -1;                  /* over 48 bits */
  87
  88   return 0;
  89 }
  90
  91 uint32_t
  92 _gnutls_uint24touint32 (uint24 num)
  93 {
  94   uint32_t ret = 0;
  95
  96   ((uint8_t *) & ret)[1] = num.pint[0];
  97   ((uint8_t *) & ret)[2] = num.pint[1];
  98   ((uint8_t *) & ret)[3] = num.pint[2];
  99   return ret;
 100 }
 101
 102 uint24
 103 _gnutls_uint32touint24 (uint32_t num)
 104 {
 105   uint24 ret;
 106
 107   ret.pint[0] = ((uint8_t *) & num)[1];
 108   ret.pint[1] = ((uint8_t *) & num)[2];
 109   ret.pint[2] = ((uint8_t *) & num)[3];
 110   return ret;
 111
 112 }
 113
 114 /* data should be at least 3 bytes */
 115 uint32_t
 116 _gnutls_read_uint24 (const uint8_t * data)
 117 {
 118   uint32_t res;
 119   uint24 num;
 120
 121   num.pint[0] = data[0];
 122   num.pint[1] = data[1];
 123   num.pint[2] = data[2];
 124
 125   res = _gnutls_uint24touint32 (num);
 126 #ifndef WORDS_BIGENDIAN
 127   res = bswap_32 (res);
 128 #endif
 129   return res;
 130 }
 131
 132 void
 133 _gnutls_write_uint64 (uint64_t num, uint8_t * data)
 134 {
 135 #ifndef WORDS_BIGENDIAN
 136   num = bswap_64 (num);
 137 #endif
 138   memcpy(data, &num, 8);
 139 }
 140
 141 void
 142 _gnutls_write_uint24 (uint32_t num, uint8_t * data)
 143 {
 144   uint24 tmp;
 145
 146 #ifndef WORDS_BIGENDIAN
 147   num = bswap_32 (num);
 148 #endif
 149   tmp = _gnutls_uint32touint24 (num);
 150
 151   data[0] = tmp.pint[0];
 152   data[1] = tmp.pint[1];
 153   data[2] = tmp.pint[2];
 154 }
 155
 156 uint32_t
 157 _gnutls_read_uint32 (const uint8_t * data)
 158 {
 159   uint32_t res;
 160
 161   memcpy (&res, data, sizeof (uint32_t));
 162 #ifndef WORDS_BIGENDIAN
 163   res = bswap_32 (res);
 164 #endif
 165   return res;
 166 }
 167
 168 void
 169 _gnutls_write_uint32 (uint32_t num, uint8_t * data)
 170 {
 171
 172 #ifndef WORDS_BIGENDIAN
 173   num = bswap_32 (num);
 174 #endif
 175   memcpy (data, &num, sizeof (uint32_t));
 176 }
 177
 178 uint16_t
 179 _gnutls_read_uint16 (const uint8_t * data)
 180 {
 181   uint16_t res;
 182   memcpy (&res, data, sizeof (uint16_t));
 183 #ifndef WORDS_BIGENDIAN
 184   res = bswap_16 (res);
 185 #endif
 186   return res;
 187 }
 188
 189 void
 190 _gnutls_write_uint16 (uint16_t num, uint8_t * data)
 191 {
 192
 193 #ifndef WORDS_BIGENDIAN
 194   num = bswap_16 (num);
 195 #endif
 196   memcpy (data, &num, sizeof (uint16_t));
 197 }
 198
 199 uint32_t
 200 _gnutls_conv_uint32 (uint32_t data)
 201 {
 202 #ifndef WORDS_BIGENDIAN
 203   return bswap_32 (data);
 204 #else
 205   return data;
 206 #endif
 207 }
 208
 209 uint16_t
 210 _gnutls_conv_uint16 (uint16_t data)
 211 {
 212 #ifndef WORDS_BIGENDIAN
 213   return bswap_16 (data);
 214 #else
 215   return data;
 216 #endif
 217 }
 218
 219 uint32_t
 220 _gnutls_uint64touint32 (const uint64 * num)
 221 {
 222   uint32_t ret;
 223
 224   memcpy (&ret, &num->i[4], 4);
 225 #ifndef WORDS_BIGENDIAN
 226   ret = bswap_32 (ret);
 227 #endif
 228
 229   return ret;
 230 }
 231