functions/imap_utf7_local.php

   1 <?php
   2
   3 /**
   4  * functions/imap_utf7_local.php - utf7-imap functions
   5  *
   6  * This implements all functions that do imap UTF7 conversions.
   7  * Before 1.3.2 functions were stored in imap_utf7_decode_local.php and
   8  * imap_utf7_encode_local.php files.
   9  *
  10  * @copyright &copy; 1999-2007 The SquirrelMail Project Team
  11  * @license http://opensource.org/licenses/gpl-license.php GNU Public License
  12  * @version $Id$
  13  * @package squirrelmail
  14  * @subpackage imap
  15  * @since 1.3.2
  16  */
  17
  18 /**
  19  * Function that uses php mbstring functions to convert from and to utf7-imap charset
  20  *
  21  * Since 1.5.1 list of supported charsets depends sq_mb_list_encoding function.
  22  * Before that it was hardcoded to iso-8859-x, utf-8 and iso-2022-jp.
  23  * @param string $str folder name
  24  * @param string $to_encoding name of resulting charset
  25  * @param string $from_encoding name of original charset
  26  * @param string $default_charset default charset used by translation.
  27  * @return string encoded folder name or ''
  28  * @since 1.4.2
  29  */
  30 function sqimap_mb_convert_encoding($str, $to_encoding, $from_encoding, $default_charset) {
  31     $supported_encodings=sq_mb_list_encodings();
  32     if ( in_array(strtolower($default_charset),$supported_encodings) &&
  33          function_exists('mb_convert_encoding')) {
  34         return mb_convert_encoding($str, $to_encoding, $from_encoding);
  35     }
  36     return '';
  37 }
  38
  39 /**
  40  * encode folder name to utf7-imap
  41  *
  42  * If mbstring functions do not support charset used by translation, falls back to iso-8859-1
  43  * @param string $s folder name
  44  * @return string utf7-imap encoded folder name
  45  * @since 1.2.7
  46  */
  47 function imap_utf7_encode_local($s) {
  48     global $languages, $squirrelmail_language;
  49
  50     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
  51             function_exists($languages[$squirrelmail_language]['XTRA_CODE'].'_utf7_imap_encode')) {
  52         return call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_utf7_imap_encode', $s);
  53     }
  54
  55     if ($s == '')    //If empty, don't bother
  56         return '';
  57
  58     global $default_charset;
  59     set_my_charset();    //must be called before using $default_charset
  60     if ((strtolower($default_charset) != 'iso-8859-1') && ($default_charset != '')) {
  61         $utf7_s = sqimap_mb_convert_encoding($s, 'UTF7-IMAP', $default_charset, $default_charset);
  62         if ($utf7_s != '')
  63             return $utf7_s;
  64     }
  65
  66     // Later code works only for ISO-8859-1
  67
  68     $b64_s = '';     // buffer for substring to be base64-encoded
  69     $utf7_s = '';    // imap-utf7-encoded string
  70     for ($i = 0; $i < strlen($s); $i++) {
  71         $c = $s[$i];
  72         $ord_c = ord($c);
  73         if ((($ord_c >= 0x20) and ($ord_c <= 0x25)) or
  74                 (($ord_c >= 0x27) and ($ord_c <= 0x7e))) {
  75             if ($b64_s) {
  76                 $utf7_s = $utf7_s . '&' . encodeBASE64($b64_s) .'-';
  77                 $b64_s = '';
  78             }
  79             $utf7_s = $utf7_s . $c;
  80         } elseif ($ord_c == 0x26) {
  81             if ($b64_s) {
  82                 $utf7_s = $utf7_s . '&' . encodeBASE64($b64_s) . '-';
  83                 $b64_s = '';
  84             }
  85             $utf7_s = $utf7_s . '&-';
  86         } else {
  87             $b64_s = $b64_s . chr(0) . $c;
  88         }
  89     }
  90     //
  91     // flush buffer
  92     //
  93     if ($b64_s) {
  94         $utf7_s = $utf7_s . '&' . encodeBASE64($b64_s) . '-';
  95         $b64_s = '';
  96     }
  97     return $utf7_s;
  98 }
  99
 100 /**
 101  * converts folder name from utf7-imap to charset used by translation
 102  *
 103  * If mbstring functions do not support charset used by translation, falls back to iso-8859-1
 104  * @param string $s folder name in utf7-imap
 105  * @return string folder name in charset used by translation
 106  * @since 1.2.7
 107  */
 108 function imap_utf7_decode_local($s) {
 109     global $languages, $squirrelmail_language;
 110
 111     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 112             function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_utf7_imap_decode')) {
 113         return call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_utf7_imap_decode', $s);
 114     }
 115
 116     if ($s == '')    //If empty, don't bother
 117         return '';
 118
 119     global $default_charset;
 120     set_my_charset();    //must be called before using $default_charset
 121     if ((strtolower($default_charset) != 'iso-8859-1') && ($default_charset != '')) {
 122         $utf7_s = sqimap_mb_convert_encoding($s, $default_charset, 'UTF7-IMAP', $default_charset);
 123         if ($utf7_s != '')
 124             return $utf7_s;
 125     }
 126
 127     // Later code works only for ISO-8859-1
 128
 129     $b64_s = '';
 130     $iso_8859_1_s = '';
 131     for ($i = 0, $len = strlen($s); $i < $len; $i++) {
 132         $c = $s[$i];
 133         if (strlen($b64_s) > 0) {
 134             if ($c == '-') {
 135                 if ($b64_s == '&') {
 136                     $iso_8859_1_s = $iso_8859_1_s . '&';
 137                 } else {
 138                     $iso_8859_1_s = $iso_8859_1_s .
 139                         decodeBASE64(substr($b64_s, 1));
 140                 }
 141                 $b64_s = '';
 142             } else {
 143                 $b64_s = $b64_s . $c;
 144             }
 145         } else {
 146             if ($c == '&') {
 147                 $b64_s = '&';
 148             } else {
 149                 $iso_8859_1_s = $iso_8859_1_s . $c;
 150             }
 151         }
 152     }
 153     return $iso_8859_1_s;
 154 }
 155 /**
 156  * Converts string to base64
 157  * @param string $s string
 158  * @return string base64 encoded string
 159  * @since 1.2.7
 160  */
 161 function encodeBASE64($s) {
 162     $B64Chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,';
 163     $p = 0;     // phase: 1 / 2 / 3 / 1 / 2 / 3...
 164     $e = '';    // base64-encoded string
 165     //foreach($s as $c) {
 166     for ($i = 0; $i < strlen($s); $i++) {
 167         $c = $s[$i];
 168         if ($p == 0) {
 169             $e = $e . substr($B64Chars, ((ord($c) & 252) >> 2), 1);
 170             $t = (ord($c) & 3);
 171             $p = 1;
 172         } elseif ($p == 1) {
 173             $e = $e . $B64Chars[($t << 4) + ((ord($c) & 240) >> 4)];
 174             $t = (ord($c) & 15);
 175             $p = 2;
 176         } elseif ($p == 2) {
 177             $e = $e . $B64Chars[($t << 2) + ((ord($c) & 192) >> 6)];
 178             $e = $e . $B64Chars[ord($c) & 63];
 179             $p = 0;
 180         }
 181     }
 182     //
 183     // flush buffer
 184     //
 185     if ($p == 1) {
 186         $e = $e . $B64Chars[$t << 4];
 187     } elseif ($p == 2) {
 188         $e = $e . $B64Chars[$t << 2];
 189     }
 190     return $e;
 191 }
 192
 193 /**
 194  * Converts string from base64
 195  * @param string $s base64 encoded string
 196  * @return string decoded string
 197  * @since 1.2.7
 198  */
 199 function decodeBASE64($s) {
 200     $B64Values = array(
 201             'A' =>  0, 'B' =>  1, 'C' =>  2, 'D' =>  3, 'E' =>  4, 'F' =>  5,
 202             'G' =>  6, 'H' =>  7, 'I' =>  8, 'J' =>  9, 'K' => 10, 'L' => 11,
 203             'M' => 12, 'N' => 13, 'O' => 14, 'P' => 15, 'Q' => 16, 'R' => 17,
 204             'S' => 18, 'T' => 19, 'U' => 20, 'V' => 21, 'W' => 22, 'X' => 23,
 205             'Y' => 24, 'Z' => 25,
 206             'a' => 26, 'b' => 27, 'c' => 28, 'd' => 29, 'e' => 30, 'f' => 31,
 207             'g' => 32, 'h' => 33, 'i' => 34, 'j' => 35, 'k' => 36, 'l' => 37,
 208             'm' => 38, 'n' => 39, 'o' => 40, 'p' => 41, 'q' => 42, 'r' => 43,
 209             's' => 44, 't' => 45, 'u' => 46, 'v' => 47, 'w' => 48, 'x' => 49,
 210             'y' => 50, 'z' => 51,
 211             '0' => 52, '1' => 53, '2' => 54, '3' => 55, '4' => 56, '5' => 57,
 212             '6' => 58, '7' => 59, '8' => 60, '9' => 61, '+' => 62, ',' => 63
 213             );
 214     $p = 0;
 215     $d = '';
 216     $unicodeNullByteToggle = 0;
 217     for ($i = 0, $len = strlen($s); $i < $len; $i++) {
 218         $c = $s[$i];
 219         if ($p == 0) {
 220             $t = $B64Values[$c];
 221             $p = 1;
 222         } elseif ($p == 1) {
 223             if ($unicodeNullByteToggle) {
 224                 $d = $d . chr(($t << 2) + (($B64Values[$c] & 48) >> 4));
 225                 $unicodeNullByteToggle = 0;
 226             } else {
 227                 $unicodeNullByteToggle = 1;
 228             }
 229             $t = ($B64Values[$c] & 15);
 230             $p = 2;
 231         } elseif ($p == 2) {
 232             if ($unicodeNullByteToggle) {
 233                 $d = $d . chr(($t << 4) + (($B64Values[$c] & 60) >> 2));
 234                 $unicodeNullByteToggle = 0;
 235             } else {
 236                 $unicodeNullByteToggle = 1;
 237             }
 238             $t = ($B64Values[$c] & 3);
 239             $p = 3;
 240         } elseif ($p == 3) {
 241             if ($unicodeNullByteToggle) {
 242                 $d = $d . chr(($t << 6) + $B64Values[$c]);
 243                 $unicodeNullByteToggle = 0;
 244             } else {
 245                 $unicodeNullByteToggle = 1;
 246             }
 247             $t = ($B64Values[$c] & 3);
 248             $p = 0;
 249         }
 250     }
 251     return $d;
 252 }