lib/gnutls_num.c

   1 /*
   2  * Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2010 Free
   3  * Software Foundation, Inc.
   4  *
   5  * Author: Nikos Mavrogiannopoulos
   6  *
   7  * This file is part of GnuTLS.
   8  *
   9  * The GnuTLS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  22  * USA
  23  *
  24  */
  25
  26 /* This file contains the functions needed for 64 bit integer support in
  27  * TLS, and functions which ease the access to TLS vectors (data of given size).
  28  */
  29
  30 #include <gnutls_int.h>
  31 #include <gnutls_num.h>
  32 #include <gnutls_errors.h>
  33
  34 #include <byteswap.h>
  35
  36 /* This function will add one to uint64 x.
  37  * Returns 0 on success, or -1 if the uint64 max limit
  38  * has been reached.
  39  */
  40 int
  41 _gnutls_uint64pp (uint64 * x)
  42 {
  43   register int i, y = 0;
  44
  45   for (i = 7; i >= 0; i--)
  46     {
  47       y = 0;
  48       if (x->i[i] == 0xff)
  49         {
  50           x->i[i] = 0;
  51           y = 1;
  52         }
  53       else
  54         x->i[i]++;
  55
  56       if (y == 0)
  57         break;
  58     }
  59   if (y != 0)
  60     return -1;                  /* over 64 bits! WOW */
  61
  62   return 0;
  63 }
  64
  65 /* This function will add one to uint48 x.
  66  * Returns 0 on success, or -1 if the uint48 max limit
  67  * has been reached.
  68  */
  69 int
  70 _gnutls_uint48pp (uint64 * x)
  71 {
  72   register int i, y = 0;
  73
  74   for (i = 7; i >= 3; i--)
  75     {
  76       y = 0;
  77       if (x->i[i] == 0xff)
  78         {
  79           x->i[i] = 0;
  80           y = 1;
  81         }
  82       else
  83         x->i[i]++;
  84
  85       if (y == 0)
  86         break;
  87     }
  88   if (y != 0)
  89     return -1;                  /* over 48 bits */
  90
  91   return 0;
  92 }
  93
  94 uint32_t
  95 _gnutls_uint24touint32 (uint24 num)
  96 {
  97   uint32_t ret = 0;
  98
  99   ((uint8_t *) & ret)[1] = num.pint[0];
 100   ((uint8_t *) & ret)[2] = num.pint[1];
 101   ((uint8_t *) & ret)[3] = num.pint[2];
 102   return ret;
 103 }
 104
 105 uint24
 106 _gnutls_uint32touint24 (uint32_t num)
 107 {
 108   uint24 ret;
 109
 110   ret.pint[0] = ((uint8_t *) & num)[1];
 111   ret.pint[1] = ((uint8_t *) & num)[2];
 112   ret.pint[2] = ((uint8_t *) & num)[3];
 113   return ret;
 114
 115 }
 116
 117 /* data should be at least 3 bytes */
 118 uint32_t
 119 _gnutls_read_uint24 (const opaque * data)
 120 {
 121   uint32_t res;
 122   uint24 num;
 123
 124   num.pint[0] = data[0];
 125   num.pint[1] = data[1];
 126   num.pint[2] = data[2];
 127
 128   res = _gnutls_uint24touint32 (num);
 129 #ifndef WORDS_BIGENDIAN
 130   res = bswap_32 (res);
 131 #endif
 132   return res;
 133 }
 134
 135 void
 136 _gnutls_write_uint24 (uint32_t num, opaque * data)
 137 {
 138   uint24 tmp;
 139
 140 #ifndef WORDS_BIGENDIAN
 141   num = bswap_32 (num);
 142 #endif
 143   tmp = _gnutls_uint32touint24 (num);
 144
 145   data[0] = tmp.pint[0];
 146   data[1] = tmp.pint[1];
 147   data[2] = tmp.pint[2];
 148 }
 149
 150 uint32_t
 151 _gnutls_read_uint32 (const opaque * data)
 152 {
 153   uint32_t res;
 154
 155   memcpy (&res, data, sizeof (uint32_t));
 156 #ifndef WORDS_BIGENDIAN
 157   res = bswap_32 (res);
 158 #endif
 159   return res;
 160 }
 161
 162 void
 163 _gnutls_write_uint32 (uint32_t num, opaque * data)
 164 {
 165
 166 #ifndef WORDS_BIGENDIAN
 167   num = bswap_32 (num);
 168 #endif
 169   memcpy (data, &num, sizeof (uint32_t));
 170 }
 171
 172 uint16_t
 173 _gnutls_read_uint16 (const opaque * data)
 174 {
 175   uint16_t res;
 176   memcpy (&res, data, sizeof (uint16_t));
 177 #ifndef WORDS_BIGENDIAN
 178   res = bswap_16 (res);
 179 #endif
 180   return res;
 181 }
 182
 183 void
 184 _gnutls_write_uint16 (uint16_t num, opaque * data)
 185 {
 186
 187 #ifndef WORDS_BIGENDIAN
 188   num = bswap_16 (num);
 189 #endif
 190   memcpy (data, &num, sizeof (uint16_t));
 191 }
 192
 193 uint32_t
 194 _gnutls_conv_uint32 (uint32_t data)
 195 {
 196 #ifndef WORDS_BIGENDIAN
 197   return bswap_32 (data);
 198 #else
 199   return data;
 200 #endif
 201 }
 202
 203 uint16_t
 204 _gnutls_conv_uint16 (uint16_t data)
 205 {
 206 #ifndef WORDS_BIGENDIAN
 207   return bswap_16 (data);
 208 #else
 209   return data;
 210 #endif
 211 }
 212
 213 uint32_t
 214 _gnutls_uint64touint32 (const uint64 * num)
 215 {
 216   uint32_t ret;
 217
 218   memcpy (&ret, &num->i[4], 4);
 219 #ifndef WORDS_BIGENDIAN
 220   ret = bswap_32 (ret);
 221 #endif
 222
 223   return ret;
 224 }
 225