Sanity check if the encrypted password isn't found in one source, to avoid a crash when invoking crypt() on it

Monotone-Parent: cbeb8ed4edd6c44d422f9251785ee9bfad432e71
Monotone-Revision: 4a37382e84f4a00ccbbc0542ef0ae4a99a954cdd

Monotone-Author: ludovic@Sophos.ca
Monotone-Date: 2011-03-29T14:34:14
Monotone-Branch: ca.inverse.sogo

SoObjects/SOGo/SQLSource.m

@@ -133,6 +133,9 @@
 - (BOOL) _isPassword: (NSString *) plainPassword
              equalTo: (NSString *) encryptedPassword
 {
+  if (!plainPassword || !encryptedPassword)
+    return NO;
+
   if ([_userPasswordAlgorithm caseInsensitiveCompare: @"none"] == NSOrderedSame)
     {
       return [plainPassword isEqualToString: encryptedPassword];