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* regarding copyright ownership. The ASF licenses this file *
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* "License"); you may not use this file except in compliance *
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package org.apache.james.protocols.smtp.core.fastfail;
import org.apache.james.protocols.api.ProtocolSession.State;
import org.apache.james.protocols.smtp.SMTPSession;
import org.apache.james.protocols.smtp.hook.HookResult;
import org.apache.james.protocols.smtp.hook.HookReturnCode;
import org.apache.james.protocols.smtp.hook.UnknownHook;
/**
* {@link UnknownHook} implementation which disconnect the client after a issue to many unknown commands
*
*
*/
public class MaxUnknownCmdHandler implements UnknownHook{
public final static int DEFAULT_MAX_UNKOWN = 5;
private final static String UNKOWN_COMMAND_COUNT = "UNKNOWN_COMMAND_COUNT";
private int maxUnknown;
public void setMaxUnknownCmdCount(int maxUnknown) {
this.maxUnknown = maxUnknown;
}
/*
* (non-Javadoc)
* @see org.apache.james.protocols.smtp.hook.UnknownHook#doUnknown(org.apache.james.protocols.smtp.SMTPSession, java.lang.String)
*/
public HookResult doUnknown(SMTPSession session, String command) {
Integer count = (Integer) session.getAttachment(UNKOWN_COMMAND_COUNT, State.Transaction);
if (count == null) {
count = 1;
} else {
count++;
}
session.setAttachment(UNKOWN_COMMAND_COUNT, count, State.Transaction);
if (count > maxUnknown) {
return new HookResult(HookReturnCode.DENY | HookReturnCode.DISCONNECT, "521", "Closing connection as to many unknown commands received");
} else {
return HookResult.declined();
}
}
}