release/src/router/matrixssl/src/crypto/peersec/base64.c

   1 /*
   2  *      base64.c
   3  *      Release $Name: MATRIXSSL_1_8_8_OPEN $
   4  *
   5  *      Base64 operations
   6  */
   7 /*
   8  *      Copyright (c) PeerSec Networks, 2002-2009. All Rights Reserved.
   9  *      The latest version of this code is available at http://www.matrixssl.org
  10  *
  11  *      This software is open source; you can redistribute it and/or modify
  12  *      it under the terms of the GNU General Public License as published by
  13  *      the Free Software Foundation; either version 2 of the License, or
  14  *      (at your option) any later version.
  15  *
  16  *      This General Public License does NOT permit incorporating this software
  17  *      into proprietary programs.  If you are unable to comply with the GPL, a
  18  *      commercial license for this software may be purchased from PeerSec Networks
  19  *      at http://www.peersec.com
  20  *
  21  *      This program is distributed in WITHOUT ANY WARRANTY; without even the
  22  *      implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  23  *      See the GNU General Public License for more details.
  24  *
  25  *      You should have received a copy of the GNU General Public License
  26  *      along with this program; if not, write to the Free Software
  27  *      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  28  *      http://www.gnu.org/copyleft/gpl.html
  29  */
  30 /******************************************************************************/
  31
  32 #include "../cryptoLayer.h"
  33
  34 static const unsigned char map[256] = {
  35 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  36 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  37 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  38 255, 255, 255, 255, 255, 255, 255,  62, 255, 255, 255,  63,
  39  52,  53,  54,  55,  56,  57,  58,  59,  60,  61, 255, 255,
  40 255, 254, 255, 255, 255,   0,   1,   2,   3,   4,   5,   6,
  41   7,   8,   9,  10,  11,  12,  13,  14,  15,  16,  17,  18,
  42  19,  20,  21,  22,  23,  24,  25, 255, 255, 255, 255, 255,
  43 255,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,
  44  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,  48,
  45  49,  50,  51, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  46 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  47 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  48 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  49 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  50 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  51 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  52 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  53 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  54 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  55 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
  56 255, 255, 255, 255 };
  57
  58 int32 ps_base64_decode(const unsigned char *in,  uint32 len,
  59                                         unsigned char *out, uint32 *outlen)
  60 {
  61         unsigned long   t, x, y, z;
  62         unsigned char   c;
  63         int32                           g;
  64
  65         if (in == NULL || out == NULL || outlen == NULL) {
  66                 return -1;
  67         }
  68         g = 3;
  69         for (x = y = z = t = 0; x < len; x++) {
  70                 c = map[in[x]&0xFF];
  71                 if (c == 255) {
  72                         continue;
  73                 }
  74 /*
  75         the final = symbols are read and used to trim the remaining bytes
  76  */
  77         if (c == 254) {
  78                 c = 0;
  79 /*
  80                 prevent g < 0 which would potentially allow an overflow later
  81  */
  82                 if (--g < 0) {
  83                         return CRYPT_INVALID_PACKET;
  84                 }
  85         } else if (g != 3) {
  86 /*
  87                 we only allow = to be at the end
  88  */
  89                 return CRYPT_INVALID_PACKET;
  90         }
  91
  92                 t = (t<<6)|c;
  93
  94                 if (++y == 4) {
  95                         if (z + g > *outlen) {
  96                                 return CRYPT_BUFFER_OVERFLOW;
  97                         }
  98                         out[z++] = (unsigned char)((t>>16)&255);
  99                         if (g > 1) {
 100                                 out[z++] = (unsigned char)((t>>8)&255);
 101                         }
 102                         if (g > 2) {
 103                                 out[z++] = (unsigned char)(t&255);
 104                         }
 105                         y = t = 0;
 106                 }
 107         }
 108         if (y != 0) {
 109                 return -1;
 110         }
 111         *outlen = z;
 112         return 0;
 113 }
 114
 115 /******************************************************************************/
 116