Make the base for the SquirrelMail URL configurable. Adds a new variable

config_base_location to config.php and a new option to conf.pl. This is
to prevent problems in installs where our heuristic doesn't work
correctly (#1521299, #1460675, #1110064, #1000850, #1113791)

I believe this is one of the most commonly reported issues in current
stable. That's why I've created the code to be minimally invasive: it only
allows to set the proto+host+port part, because this means all changes
can remain within get_location().

I want to backport this bugfix to stable so I appreciate any feedback
on it. And also of course if you think that this is the wrong way to
solve it :)

ChangeLog

@@ -100,6 +100,10 @@ Version 1.5.2 - CVS
     type options from spamcop plugin.
   - Removed trailing ?> from function scripts.
   - Added checks for non-existent backend to AddressBook class.
+  - Make the base for the SquirrelMail URL configurable. Adds a new variable
+    config_base_location to config.php and a new option to conf.pl. This is
+    to prevent problems in installs where our heuristic doesn't work
+    correctly (#1521299, #1460675, #1110064, #1000850, #1113791).
 
 Version 1.5.1 (branched on 2006-02-12)
 --------------------------------------

config/conf.pl

@@ -391,6 +391,7 @@ $abook_global_file_listing = 'true'     if ( !$abook_global_file_listing );
 $encode_header_key = ''                 if ( !$encode_header_key );
 $hide_auth_header = 'false'             if ( !$hide_auth_header );
 $time_zone_type = '0'                   if ( !$time_zone_type );
+$config_location_base = ''              if ( !$config_location_base );
 $prefs_user_size = 128                  if ( !$prefs_user_size );
 $prefs_key_size = 64                    if ( !$prefs_key_size );
 $prefs_val_size = 65536                 if ( !$prefs_val_size );
@@ -596,6 +597,7 @@ while ( ( $command ne "q" ) && ( $command ne "Q" ) && ( $command ne ":q" ) ) {
         print "13. Allow advanced search       : $WHT$allow_advanced_search$NRM\n";
         print "14. PHP session name            : $WHT$session_name$NRM\n";
         print "15. Time zone configuration     : $WHT$time_zone_type$NRM\n";
+        print "16. Location base               : $WHT$config_location_base$NRM\n";
         print "\n";
         print "R   Return to Main Menu\n";
     } elsif ( $menu == 5 ) {
@@ -831,6 +833,7 @@ while ( ( $command ne "q" ) && ( $command ne "Q" ) && ( $command ne ":q" ) ) {
             elsif ( $command == 13 ) { $allow_advanced_search    = command316(); }
             elsif ( $command == 14 ) { $session_name             = command317(); }
             elsif ( $command == 15 ) { $time_zone_type           = command318(); }
+            elsif ( $command == 16 ) { $config_location_base     = command319(); }
         } elsif ( $menu == 5 ) {
             if ( $command == 1 ) { $templateset_default = command_templates(); }
             elsif ( $command == 2 ) { $theme_css = command42(); }
@@ -2441,6 +2444,25 @@ sub command318 {
     return $time_zone_type;
 }
 
+# set the location base for redirects (since 1.5.2)
+sub command319 {
+    print "Here you can set the base part of the SquirrelMail URL.\n";
+    print "It is normally autodetected but if that fails, use this\n";
+    print "option to override.\n";
+    print "It should contain only the protocol and hostname/port parts\n";
+    print "of the URL; the full path will be appended automatically.\n\n";
+    print "Examples:\nhttp://webmail.example.org\nhttp://webmail.example.com:8080\nhttps://webmail.example.com:6691\n\n";
+    print "Do not add any path elements.\n";
+
+    print "URL base? [" .$WHT."autodetect$NRM]: $WHT";
+    $new_config_location_base = <STDIN>;
+    chomp($new_config_location_base);
+    $config_location_base = $new_config_location_base;
+    
+    return $config_location_base;
+}
+
+
 
 sub command41 {
     print "\nDefine the themes that you wish to use.  If you have added ";
@@ -3971,9 +3993,9 @@ sub save_data {
         # boolean
         print CF "\$hide_auth_header         = $hide_auth_header;\n";
         # boolean
-        print CF "\$disable_thread_sort     = $disable_thread_sort;\n";
+        print CF "\$disable_thread_sort      = $disable_thread_sort;\n";
         # boolean
-        print CF "\$disable_server_sort     = $disable_server_sort;\n";
+        print CF "\$disable_server_sort      = $disable_server_sort;\n";
         # boolean
         print CF "\$allow_charset_search     = $allow_charset_search;\n";
         # integer
@@ -3982,6 +4004,9 @@ sub save_data {
         # integer
         print CF "\$time_zone_type           = $time_zone_type;\n";
         print CF "\n";
+        # string
+        print CF "\$config_location_base     = '$config_location_base';\n";
+        print CF "\n";
 
         # all plugins are strings
         for ( $ct = 0 ; $ct <= $#plugins ; $ct++ ) {

config/config_default.php

@@ -1119,6 +1119,29 @@ $lossy_encoding = false;
  */
 $time_zone_type = 0;
 
+/**
+ * Location base
+ * 
+ * This is used to build the URL to the SquirrelMail location.
+ * It should contain only the protocol and hostname/port parts
+ * of the URL; the full path will be appended automatically.
+ *
+ * If not specified or empty, it will be autodetected.
+ *
+ * Examples:
+ * http://webmail.example.org
+ * http://webmail.example.com:8080
+ * https://webmail.example.com:6691
+ *
+ * To be clear: do not include any of the path elements, so if
+ * SquirrelMail is at http://www.example.net/web/mail/src/login.php, you
+ * write: http://www.example.net
+ *
+ * @global string $config_location_base;
+ * @since 1.5.2
+ */
+$config_location_base = '';
+
 /*** Tweaks ***/
 /**
  * Iframe sandbox code control

functions/strings.php

@@ -460,18 +460,17 @@ function readShortMailboxName($haystack, $needle) {
  *
  * Determines the location to forward to, relative to your server.
  * This is used in HTTP Location: redirects.
- * If this doesnt work correctly for you (although it should), you can
- * remove all this code except the last two lines, and have it return
- * the right URL for your site, something like:
  *
- *   http://www.example.com/squirrelmail/
+ * If set, it uses $config_location_base as the first part of the URL,
+ * specifically, the protocol, hostname and port parts. The path is
+ * always autodetected.
  *
  * @return string the base url for this SquirrelMail installation
  * @since 1.0
  */
 function get_location () {
 
-    global $imap_server_type;
+    global $imap_server_type, $config_location_base;
 
     /* Get the path, handle virtual directories */
     if(strpos(php_self(), '?')) {
@@ -480,9 +479,16 @@ function get_location () {
         $path = php_self();
     }
     $path = substr($path, 0, strrpos($path, '/'));
+
+    // proto+host+port are already set in config:
+    if ( !empty($config_location_base) ) {
+        return $config_location_base . $path ;
+    }
+    // we computed it before, get it from the session:
     if ( sqgetGlobalVar('sq_base_url', $full_url, SQ_SESSION) ) {
       return $full_url . $path;
     }
+    // else: autodetect
 
     /* Check if this is a HTTPS or regular HTTP request. */
     $proto = 'http://';
@@ -518,19 +524,19 @@ function get_location () {
         }
     }
 
-   /* this is a workaround for the weird macosx caching that
-      causes Apache to return 16080 as the port number, which causes
-      SM to bail */
+    /* this is a workaround for the weird macosx caching that
+     * causes Apache to return 16080 as the port number, which causes
+     * SM to bail */
 
-   if ($imap_server_type == 'macosx' && $port == ':16080') {
+    if ($imap_server_type == 'macosx' && $port == ':16080') {
         $port = '';
-   }
+    }
 
-   /* Fallback is to omit the server name and use a relative */
-   /* URI, although this is not RFC 2616 compliant.          */
-   $full_url = ($host ? $proto . $host . $port : '');
-   sqsession_register($full_url, 'sq_base_url');
-   return $full_url . $path;
+    /* Fallback is to omit the server name and use a relative */
+    /* URI, although this is not RFC 2616 compliant.          */
+    $full_url = ($host ? $proto . $host . $port : '');
+    sqsession_register($full_url, 'sq_base_url');
+    return $full_url . $path;
 }
 
 

src/configtest.php

@@ -301,7 +301,9 @@ if ( $squirrelmail_default_language != 'en_US' ) {
     echo $IND . "Default language OK.<br />\n";
 }
 
-echo $IND . "Base URL detected as: <tt>" . htmlspecialchars($test_location) . "</tt><br />\n";
+echo $IND . "Base URL detected as: <tt>" . htmlspecialchars($test_location) .
+    "</tt> (location base " . (empty($config_location_base) ? 'autodetected' : 'set to <tt>' .
+    htmlspecialchars($config_location_base)."</tt>") . ")<br />\n";
 
 /* check minimal requirements for other security options */