Use Delivered-To header as a last resort for identity selection (#1488840)

CHANGELOG

@@ -1,6 +1,7 @@
 CHANGELOG Roundcube Webmail
 ===========================
 
+- Use Delivered-To header as a last resort for identity selection (#1488840)
 - Fix XSS vulnerability using Flash files (#1488828)
 - Fix absolute positioning in HTML messages (#1488819)
 - Fix cache (in)validation after setting \Deleted flag

program/lib/Roundcube/rcube_imap_generic.php

@@ -2206,10 +2206,13 @@ class rcube_imap_generic
                             }
                             break;
                         default:
-                            if (strlen($field) > 2) {
-                                $result[$id]->others[$field] = $string;
+                            if (strlen($field) < 3) {
+                                break;
                             }
-                            break;
+                            if ($result[$id]->others[$field]) {
+                                $string = array_merge((array)$result[$id]->others[$field], (array)$string);
+                            }
+                            $result[$id]->others[$field] = $string;
                         }
                     }
                 }
@@ -2217,7 +2220,6 @@ class rcube_imap_generic
 
             // VANISHED response (QRESYNC RFC5162)
             // Sample: * VANISHED (EARLIER) 300:310,405,411
-
             else if (preg_match('/^\* VANISHED [()EARLIER]*/i', $line, $match)) {
                 $line   = substr($line, strlen($match[0]));
                 $v_data = $this->tokenizeResponse($line, 1);

program/lib/Roundcube/rcube_storage.php

@@ -64,6 +64,7 @@ abstract class rcube_storage
         'MAIL-FOLLOWUP-TO',
         'MAIL-REPLY-TO',
         'RETURN-PATH',
+        'DELIVERED-TO',
     );
 
     const UNKNOWN       = 0;

program/steps/mail/compose.inc

@@ -298,7 +298,6 @@ else if (count($MESSAGE->identities)) {
   $from_idx         = null;
   $found_idx        = null;
   $default_identity = 0; // default identity is always first on the list
-  $return_path      = $MESSAGE->headers->others['return-path'];
 
   // Select identity
   foreach ($MESSAGE->identities as $idx => $ident) {
@@ -332,8 +331,8 @@ else if (count($MESSAGE->identities)) {
     $from_idx = $found_idx;
   }
 
-  // Fallback using Return-Path
-  if ($from_idx === null && $return_path) {
+  // Try Return-Path
+  if ($from_idx === null && ($return_path = $MESSAGE->headers->others['return-path'])) {
     foreach ($MESSAGE->identities as $idx => $ident) {
       if (strpos($return_path, str_replace('@', '=', $ident['email_ascii']).'@') !== false) {
         $from_idx = $idx;
@@ -342,6 +341,16 @@ else if (count($MESSAGE->identities)) {
     }
   }
 
+  // Fallback using Delivered-To
+  if ($from_idx === null && ($delivered_to = $MESSAGE->headers->others['delivered-to'])) {
+    foreach ($MESSAGE->identities as $idx => $ident) {
+      if (in_array($ident['email_ascii'], $delivered_to)) {
+        $from_idx = $idx;
+        break;
+      }
+    }
+  }
+
   $ident   = $MESSAGE->identities[$from_idx !== null ? $from_idx : $default_identity];
   $from_id = $ident['identity_id'];