include/heimdal/asnencode.php

   1 <?php
   2 /*
   3  * asnencode.php,v 1.0 2006/08/25 21:00:00
   4  *
   5  * Copyright 2006 Alejandro Escanero Blanco <aescanero@chaosdimension.org>
   6  *
   7  * See the enclosed file COPYING for license information (GPL).  If you
   8  * did not receive this file, see http://www.fsf.org/copyleft/gpl.html.
   9  */
  10
  11
  12 class stream{
  13
  14         var $stream;
  15         var $len;
  16
  17         function stream(){
  18                 $this->stream=array();
  19                 $len=0;
  20         }
  21
  22         function writeVal($val){
  23                 $val=($val & 0xff); //Only one byte
  24                 array_push($this->stream,$val);
  25                 $this->len++;
  26         }
  27
  28         function writeArray($arr){
  29                 foreach ($arr as $val)
  30                         array_push($this->stream,$val);
  31
  32                 $this->len+=count($arr);
  33         }
  34
  35         function writeStream($stream){
  36                 $str=$stream->getStream();
  37 //              print_r($this->stream);
  38                 foreach ($str as $val)
  39                         array_push($this->stream,$val);
  40                 $this->len+=count($str);
  41         }
  42
  43         function writeOctetString($os){
  44                 $len=strlen($os);
  45                 $arr=array($len);
  46                 for($i=0;$i<$len;$i++) $arr[$i]=ord(substr($os,$i,1));
  47                 $this->writeArray($arr);
  48         }
  49
  50         function getStream(){
  51                 return($this->stream);
  52         }
  53
  54         function getLen(){
  55                 return($this->len);
  56         }
  57
  58         function printOut($debug=false,$msg=""){
  59                 if($debug) printf("%s len: %d\n",$msg,$this->len);
  60 //              print_r($this->stream);
  61                 $stringh="";
  62                 for ($i=0;$i<$this->len;$i++) $stringh.=sprintf(" %d %02x\n",$i,$this->stream[$i]);
  63                 printf("%s ASN: %s\n",$msg,$stringh);
  64         }
  65
  66         function printString($debug=false,$msg=""){
  67                 $stringh="";
  68                 for ($i=0;$i<$this->len;$i++) $stringh.=chr($this->stream[$i]);
  69                 return($stringh);
  70         }
  71 };
  72
  73
  74 class asnEncode{
  75
  76         var $stream;
  77
  78         function asnEncode(){
  79                 $this->stream=new stream();
  80         }
  81
  82         function encodeOctetString($os){
  83                 $len=strlen($os);
  84                 $this->encodeTag(UNIVERSAL,OCTET_STRING,false,&$this->stream);
  85                 $this->encodeLen($len,&$this->stream);
  86                 $this->stream->writeOctetString($os);
  87         }
  88
  89         function encodeTag($clazz,$value,$constructed,$stream){
  90                 if ($constructed)
  91                         $clazz |= 0x20;
  92                 if ($value < 0x1F){
  93                         $stream->writeVal($clazz | $value);
  94                 } else {
  95                         $stream->writeVal($clazz | 0x1F);
  96                         $clazz = $value;
  97                         while ($clazz > 63) {
  98                                 $stream->writeVal(63);
  99                                 $clazz -= 63;
 100                         }
 101                         $stream->writeVal($clazz);
 102                 }
 103                 return($stream);
 104         }
 105
 106         function encodeInteger($val){
 107
 108                 $dh=dechex($val);
 109                 $ldh=strlen($dh);
 110                 if($ldh%2 !=0){
 111                         $ldh="0".$ldh;
 112                         $ldh++;
 113                 }
 114                 $cero=0;
 115                 if($i==0)
 116                                 if(hexdec(substr($dh,0,2))>127) $cero=1;
 117                 $this->encodeTag(UNIVERSAL,INTEGER,false,&$this->stream);
 118                 $this->encodeLen(($ldh/2)+$cero,&$this->stream);
 119                 for($i=0;$i<($ldh/2);$i++){
 120                         if($i==0 && $cero==1) $this->stream->writeVal(0);
 121                         $this->stream->writeVal(hexdec(substr($dh,$i*2,2)));
 122                 }
 123         }
 124
 125
 126         function encodeLen($val,$stream){
 127                 if ($val < 128) { // short definite form
 128                         $stream->writeVal($val);
 129                         return;
 130                 }
 131                 if ($val < 256) { // long definite form
 132                         //$this->stream->writeVal(-127);
 133                         $stream->writeVal(0x81);
 134                         $stream->writeVal($val);
 135                         return;
 136                 }
 137                 if ($val < 65536) {
 138                         //$this->stream->writeVal(-126);
 139                         $stream->writeVal(0x80);
 140                         $stream->writeVal($val >> 8);
 141                         $stream->writeVal($val);
 142                         return;
 143                 }
 144                 if ($val < 16777216) {
 145                         //$this->stream->writeVal(-125);
 146                         $stream->writeVal(0x79);
 147                         $stream->writeVal($val >> 16);
 148                         $stream->writeVal($val >>  8);
 149                         $stream->writeVal($val);
 150                         return;
 151                 }
 152                 //$this->stream->writeVal(-124);
 153                 $stream->writeVal(0x78);
 154                 $stream->writeVal($val >> 24);
 155                 $stream->writeVal($val >> 16);
 156                 $stream->writeVal($val >>  8);
 157                 $stream->writeVal($val);
 158                 return($stream);
 159         }
 160
 161         function printOut(){
 162                 $this->stream->printOut();
 163         }
 164
 165         function printString(){
 166                 return($this->stream->printString());
 167         }
 168
 169         function getStream(){
 170                 return($this->stream);
 171         }
 172
 173         function encodeSequence($ix,$stream){
 174                 $hix=0xa0+$ix;
 175                 $len=$stream->getLen();
 176                 $local=new stream();
 177                 $local->writeVal($hix);
 178                 $this->encodeLen($len,&$local);
 179                 $local->writeStream($stream);
 180                 $this->stream->writeStream($local);
 181                 return($local);
 182         }
 183
 184         function encodeObject($tag,$stream){
 185                 $len=$stream->getLen();
 186                 //$this->encodeTag(UNIVERSAL,$tag,false,&$this->stream);
 187                 $this->stream->writeVal($tag);
 188                 $this->encodeLen($len,&$this->stream);
 189                 $this->stream->writeStream($stream);
 190         }
 191
 192 };
 193
 194 ?>