From d25a2aa6cc495440511c279a92088e9fde6ad5b5 Mon Sep 17 00:00:00 2001
From: mguessan <mguessan@3d1905a2-6b24-0410-a738-b14d5a86fcbd>
Date: Thu, 12 Dec 2013 21:36:21 +0000
Subject: [PATCH] EWS: improve ItemId vs user provided item name detection

git-svn-id: http://svn.code.sf.net/p/davmail/code/trunk@2201 3d1905a2-6b24-0410-a738-b14d5a86fcbd
---
 src/java/davmail/exchange/ews/EwsExchangeSession.java | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/java/davmail/exchange/ews/EwsExchangeSession.java b/src/java/davmail/exchange/ews/EwsExchangeSession.java
index 9d97bae0..064162b3 100644
--- a/src/java/davmail/exchange/ews/EwsExchangeSession.java
+++ b/src/java/davmail/exchange/ews/EwsExchangeSession.java
@@ -2443,8 +2443,16 @@ public class EwsExchangeSession extends ExchangeSession {
         return dateFormatter.format(date);
     }
 
+    /**
+     * Check if itemName is long and base64 encoded.
+     * User generated item names are usually short
+     * @param itemName item name
+     * @return true if itemName is an EWS item id
+     */
     protected static boolean isItemId(String itemName) {
-        return itemName.length() >= 152;
+        return itemName.length() >= 152
+                // item name is base64
+                && itemName.matches("^([A-Za-z0-9+/]{4})*([A-Za-z0-9+/]{4}|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{2}==)$");
     }