- Exclude MIME functionality from rcube_imap class into rcube_mime class

1 files changed, 484 insertions, 0 deletions

diff --git a/program/include/rcube_mime.php b/program/include/rcube_mime.php
new file mode 100644
index 000000000..4d97199c3
--- /dev/null
+++ b/program/include/rcube_mime.php
@@ -0,0 +1,484 @@
+<?php
+
+/**
+ +-----------------------------------------------------------------------+
+ | program/include/rcube_mime.php                                        |
+ |                                                                       |
+ | This file is part of the Roundcube Webmail client                     |
+ | Copyright (C) 2005-2012, The Roundcube Dev Team                       |
+ | Copyright (C) 2011-2012, Kolab Systems AG                             |
+ | Licensed under the GNU GPL                                            |
+ |                                                                       |
+ | PURPOSE:                                                              |
+ |   MIME message parsing utilities                                      |
+ |                                                                       |
+ +-----------------------------------------------------------------------+
+ | Author: Thomas Bruederli <roundcube@gmail.com>                        |
+ | Author: Aleksander Machniak <alec@alec.pl>                            |
+ +-----------------------------------------------------------------------+
+
+ $Id$
+
+*/
+
+
+/**
+ * Class for parsing MIME messages
+ *
+ * @package Mail
+ * @author  Thomas Bruederli <roundcube@gmail.com>
+ * @author  Aleksander Machniak <alec@alec.pl>
+ */
+class rcube_mime
+{
+    private static $default_charset = RCMAIL_CHARSET;
+
+
+    /**
+     * Object constructor.
+     */
+    function __construct($default_charset = null)
+    {
+        if ($default_charset) {
+            self::$default_charset = $default_charset;
+        }
+        else {
+            self::$default_charset = rcmail::get_instance()->config->get('default_charset', RCMAIL_CHARSET);
+        }
+    }
+
+
+    /**
+     * Split an address list into a structured array list
+     *
+     * @param string  $input    Input string
+     * @param int     $max      List only this number of addresses
+     * @param boolean $decode   Decode address strings
+     * @param string  $fallback Fallback charset if none specified
+     *
+     * @return array  Indexed list of addresses
+     */
+    static function decode_address_list($input, $max = null, $decode = true, $fallback = null)
+    {
+        $a   = self::parse_address_list($input, $decode, $fallback);
+        $out = array();
+        $j   = 0;
+
+        // Special chars as defined by RFC 822 need to in quoted string (or escaped).
+        $special_chars = '[\(\)\<\>\\\.\[\]@,;:"]';
+
+        if (!is_array($a))
+            return $out;
+
+        foreach ($a as $val) {
+            $j++;
+            $address = trim($val['address']);
+            $name    = trim($val['name']);
+
+            if ($name && $address && $name != $address)
+                $string = sprintf('%s <%s>', preg_match("/$special_chars/", $name) ? '"'.addcslashes($name, '"').'"' : $name, $address);
+            else if ($address)
+                $string = $address;
+            else if ($name)
+                $string = $name;
+
+            $out[$j] = array(
+                'name'   => $name,
+                'mailto' => $address,
+                'string' => $string
+            );
+
+            if ($max && $j==$max)
+                break;
+        }
+
+        return $out;
+    }
+
+
+    /**
+     * Decode a message header value
+     *
+     * @param string  $input         Header value
+     * @param string  $fallback      Fallback charset if none specified
+     *
+     * @return string Decoded string
+     */
+    public static function decode_header($input, $fallback = null)
+    {
+        $str = self::decode_mime_string((string)$input, $fallback);
+
+        return $str;
+    }
+
+
+    /**
+     * Decode a mime-encoded string to internal charset
+     *
+     * @param string $input    Header value
+     * @param string $fallback Fallback charset if none specified
+     *
+     * @return string Decoded string
+     */
+    public static function decode_mime_string($input, $fallback = null)
+    {
+        $default_charset = !empty($fallback) ? $fallback : self::$default_charset;
+
+        // rfc: all line breaks or other characters not found
+        // in the Base64 Alphabet must be ignored by decoding software
+        // delete all blanks between MIME-lines, differently we can
+        // receive unnecessary blanks and broken utf-8 symbols
+        $input = preg_replace("/\?=\s+=\?/", '?==?', $input);
+
+        // encoded-word regexp
+        $re = '/=\?([^?]+)\?([BbQq])\?([^\n]*?)\?=/';
+
+        // Find all RFC2047's encoded words
+        if (preg_match_all($re, $input, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER)) {
+            // Initialize variables
+            $tmp   = array();
+            $out   = '';
+            $start = 0;
+
+            foreach ($matches as $idx => $m) {
+                $pos      = $m[0][1];
+                $charset  = $m[1][0];
+                $encoding = $m[2][0];
+                $text     = $m[3][0];
+                $length   = strlen($m[0][0]);
+
+                // Append everything that is before the text to be decoded
+                if ($start != $pos) {
+                    $substr = substr($input, $start, $pos-$start);
+                    $out   .= rcube_charset_convert($substr, $default_charset);
+                    $start  = $pos;
+                }
+                $start += $length;
+
+                // Per RFC2047, each string part "MUST represent an integral number
+                // of characters . A multi-octet character may not be split across
+                // adjacent encoded-words." However, some mailers break this, so we
+                // try to handle characters spanned across parts anyway by iterating
+                // through and aggregating sequential encoded parts with the same
+                // character set and encoding, then perform the decoding on the
+                // aggregation as a whole.
+
+                $tmp[] = $text;
+                if ($next_match = $matches[$idx+1]) {
+                    if ($next_match[0][1] == $start
+                        && $next_match[1][0] == $charset
+                        && $next_match[2][0] == $encoding
+                    ) {
+                        continue;
+                    }
+                }
+
+                $count = count($tmp);
+                $text  = '';
+
+                // Decode and join encoded-word's chunks
+                if ($encoding == 'B' || $encoding == 'b') {
+                    // base64 must be decoded a segment at a time
+                    for ($i=0; $i<$count; $i++)
+                        $text .= base64_decode($tmp[$i]);
+                }
+                else { //if ($encoding == 'Q' || $encoding == 'q') {
+                    // quoted printable can be combined and processed at once
+                    for ($i=0; $i<$count; $i++)
+                        $text .= $tmp[$i];
+
+                    $text = str_replace('_', ' ', $text);
+                    $text = quoted_printable_decode($text);
+                }
+
+                $out .= rcube_charset_convert($text, $charset);
+                $tmp = array();
+            }
+
+            // add the last part of the input string
+            if ($start != strlen($input)) {
+                $out .= rcube_charset_convert(substr($input, $start), $default_charset);
+            }
+
+            // return the results
+            return $out;
+        }
+
+        // no encoding information, use fallback
+        return rcube_charset_convert($input, $default_charset);
+    }
+
+
+    /**
+     * Decode a mime part
+     *
+     * @param string $input    Input string
+     * @param string $encoding Part encoding
+     * @return string Decoded string
+     */
+    public static function decode($input, $encoding = '7bit')
+    {
+        switch (strtolower($encoding)) {
+        case 'quoted-printable':
+            return quoted_printable_decode($input);
+        case 'base64':
+            return base64_decode($input);
+        case 'x-uuencode':
+        case 'x-uue':
+        case 'uue':
+        case 'uuencode':
+            return convert_uudecode($input);
+        case '7bit':
+        default:
+            return $input;
+        }
+    }
+
+
+    /**
+     * Split RFC822 header string into an associative array
+     * @access private
+     */
+    public static function parse_headers($headers)
+    {
+        $a_headers = array();
+        $headers = preg_replace('/\r?\n(\t| )+/', ' ', $headers);
+        $lines = explode("\n", $headers);
+        $c = count($lines);
+
+        for ($i=0; $i<$c; $i++) {
+            if ($p = strpos($lines[$i], ': ')) {
+                $field = strtolower(substr($lines[$i], 0, $p));
+                $value = trim(substr($lines[$i], $p+1));
+                if (!empty($value))
+                    $a_headers[$field] = $value;
+            }
+        }
+
+        return $a_headers;
+    }
+
+
+    /**
+     * @access private
+     */
+    private static function parse_address_list($str, $decode = true, $fallback = null)
+    {
+        // remove any newlines and carriage returns before
+        $str = preg_replace('/\r?\n(\s|\t)?/', ' ', $str);
+
+        // extract list items, remove comments
+        $str = self::explode_header_string(',;', $str, true);
+        $result = array();
+
+        // simplified regexp, supporting quoted local part
+        $email_rx = '(\S+|("\s*(?:[^"\f\n\r\t\v\b\s]+\s*)+"))@\S+';
+
+        foreach ($str as $key => $val) {
+            $name    = '';
+            $address = '';
+            $val     = trim($val);
+
+            if (preg_match('/(.*)<('.$email_rx.')>$/', $val, $m)) {
+                $address = $m[2];
+                $name    = trim($m[1]);
+            }
+            else if (preg_match('/^('.$email_rx.')$/', $val, $m)) {
+                $address = $m[1];
+                $name    = '';
+            }
+            else {
+                $name = $val;
+            }
+
+            // dequote and/or decode name
+            if ($name) {
+                if ($name[0] == '"' && $name[strlen($name)-1] == '"') {
+                    $name = substr($name, 1, -1);
+                    $name = stripslashes($name);
+                }
+                if ($decode) {
+                    $name = self::decode_header($name, $fallback);
+                }
+            }
+
+            if (!$address && $name) {
+                $address = $name;
+            }
+
+            if ($address) {
+                $result[$key] = array('name' => $name, 'address' => $address);
+            }
+        }
+
+        return $result;
+    }
+
+
+    /**
+     * Explodes header (e.g. address-list) string into array of strings
+     * using specified separator characters with proper handling
+     * of quoted-strings and comments (RFC2822)
+     *
+     * @param string $separator       String containing separator characters
+     * @param string $str             Header string
+     * @param bool   $remove_comments Enable to remove comments
+     *
+     * @return array Header items
+     */
+    public static function explode_header_string($separator, $str, $remove_comments = false)
+    {
+        $length  = strlen($str);
+        $result  = array();
+        $quoted  = false;
+        $comment = 0;
+        $out     = '';
+
+        for ($i=0; $i<$length; $i++) {
+            // we're inside a quoted string
+            if ($quoted) {
+                if ($str[$i] == '"') {
+                    $quoted = false;
+                }
+                else if ($str[$i] == "\\") {
+                    if ($comment <= 0) {
+                        $out .= "\\";
+                    }
+                    $i++;
+                }
+            }
+            // we are inside a comment string
+            else if ($comment > 0) {
+                if ($str[$i] == ')') {
+                    $comment--;
+                }
+                else if ($str[$i] == '(') {
+                    $comment++;
+                }
+                else if ($str[$i] == "\\") {
+                    $i++;
+                }
+                continue;
+            }
+            // separator, add to result array
+            else if (strpos($separator, $str[$i]) !== false) {
+                if ($out) {
+                    $result[] = $out;
+                }
+                $out = '';
+                continue;
+            }
+            // start of quoted string
+            else if ($str[$i] == '"') {
+                $quoted = true;
+            }
+            // start of comment
+            else if ($remove_comments && $str[$i] == '(') {
+                $comment++;
+            }
+
+            if ($comment <= 0) {
+                $out .= $str[$i];
+            }
+        }
+
+        if ($out && $comment <= 0) {
+            $result[] = $out;
+        }
+
+        return $result;
+    }
+
+
+    /**
+     * Interpret a format=flowed message body according to RFC 2646
+     *
+     * @param string  $text Raw body formatted as flowed text
+     *
+     * @return string Interpreted text with unwrapped lines and stuffed space removed
+     */
+    public static function unfold_flowed($text)
+    {
+        $text = preg_split('/\r?\n/', $text);
+        $last = -1;
+        $q_level = 0;
+
+        foreach ($text as $idx => $line) {
+            if ($line[0] == '>' && preg_match('/^(>+\s*)/', $line, $regs)) {
+                $q = strlen(str_replace(' ', '', $regs[0]));
+                $line = substr($line, strlen($regs[0]));
+
+                if ($q == $q_level && $line
+                    && isset($text[$last])
+                    && $text[$last][strlen($text[$last])-1] == ' '
+                ) {
+                    $text[$last] .= $line;
+                    unset($text[$idx]);
+                }
+                else {
+                    $last = $idx;
+                }
+            }
+            else {
+                $q = 0;
+                if ($line == '-- ') {
+                    $last = $idx;
+                }
+                else {
+                    // remove space-stuffing
+                    $line = preg_replace('/^\s/', '', $line);
+
+                    if (isset($text[$last]) && $line
+                        && $text[$last] != '-- '
+                        && $text[$last][strlen($text[$last])-1] == ' '
+                    ) {
+                        $text[$last] .= $line;
+                        unset($text[$idx]);
+                    }
+                    else {
+                        $text[$idx] = $line;
+                        $last = $idx;
+                    }
+                }
+            }
+            $q_level = $q;
+        }
+
+        return implode("\r\n", $text);
+    }
+
+
+    /**
+     * Wrap the given text to comply with RFC 2646
+     *
+     * @param string $text Text to wrap
+     * @param int $length Length
+     *
+     * @return string Wrapped text
+     */
+    public static function format_flowed($text, $length = 72)
+    {
+        $text = preg_split('/\r?\n/', $text);
+
+        foreach ($text as $idx => $line) {
+            if ($line != '-- ') {
+                if ($line[0] == '>' && preg_match('/^(>+)/', $line, $regs)) {
+                    $prefix = $regs[0];
+                    $level = strlen($prefix);
+                    $line  = rtrim(substr($line, $level));
+                    $line  = $prefix . rc_wordwrap($line, $length - $level - 2, " \r\n$prefix ");
+                }
+                else if ($line) {
+                    $line = rc_wordwrap(rtrim($line), $length - 2, " \r\n");
+                    // space-stuffing
+                    $line = preg_replace('/(^|\r\n)(From| |>)/', '\\1 \\2', $line);
+                }
+
+                $text[$idx] = $line;
+            }
+        }
+
+        return implode("\r\n", $text);
+    }
+
+}