OF-1092: SaslServer props argument can be null.

The method signature defines that the 'props' argument is allowed to be null. Our
implementation should not throw a nullpointerexception.

src/java/org/jivesoftware/openfire/sasl/SaslServerFactoryImpl.java

@@ -132,7 +132,9 @@ public class SaslServerFactoryImpl implements SaslServerFactory
 
         for ( final Mechanism mechanism : allMechanisms )
         {
-            if ( mechanism.allowsAnonymous && props.containsKey( Sasl.POLICY_NOANONYMOUS ) && Boolean.parseBoolean( (String) props.get( Sasl.POLICY_NOANONYMOUS ) ) )
+            if ( props != null )
+            {
+                if ( mechanism.allowsAnonymous && props.containsKey( Sasl.POLICY_NOANONYMOUS ) && (Boolean) props.get( Sasl.POLICY_NOANONYMOUS ) )
                 {
                     // Do not include a mechanism that allows anonymous authentication when the 'no anonymous' policy is set.
                     continue;
@@ -143,6 +145,7 @@ public class SaslServerFactoryImpl implements SaslServerFactory
                     // Do not include a mechanism that is susceptible to simple plain passive attacks when the 'no plaintext' policy is set.
                     continue;
                 }
+            }
 
             // Mechanism passed all filters. It should be part of the result.
             result.add( mechanism.name );