hostage/src/de/tudarmstadt/informatik/hostage/format/TELNETFormatter.java

package de.tudarmstadt.informatik.hostage.format;

import de.tudarmstadt.informatik.hostage.commons.HelperUtils;

/**
 * Telnet log view formatter.
 * 
 * @author Wulf Pfeiffer
 */
public class TELNETFormatter implements ProtocolFormatter {

	public String format(String packet) {
		byte[] bytes = HelperUtils.hexStringToBytes(packet);
		String options = "Options:\n" + checkForOptions(bytes) + "\n";
		String content = "Content: " + HelperUtils.byteToStr(bytes);
		return options + content;
	}

	/**
	 * Checks a packet for option commands and returns their names as Strings.
	 * @param bytes that are checked.
	 * @return names of the option commands as String.
	 */
	private String checkForOptions(byte[] bytes) {
		StringBuffer options = new StringBuffer();
		for (int i = 0; i < bytes.length; i++) {
			if (bytes[i] == (byte) 0xff && i + 2 < bytes.length) {
				options.append(checkMode(bytes[i + 1]));
				// option name
				options.append(checkCommand(bytes[i + 2]));
			}
		}
		return options.toString();
	}
	
	/**
	 * Checks a byte for its mode value.
	 * @param b byte that is checked.
	 * @return name of the mode.
	 */
	private String checkMode(byte b) {
		switch (b) {
		case (byte) 0xfb:	return " WILL ";
		case (byte) 0xfc:	return " WON'T ";
		case (byte) 0xfd:	return " DO ";
		case (byte) 0xfe:	return " DON'T ";
		default:			return " unkown command ";
		}
	}
	
	/**
	 * Checks a byte for its command value.
	 * @param b byte that is checked.
	 * @return name of the command.
	 */
	private String checkCommand(byte b) {
		switch (b) {
		case 0x00:	return "Binary Transmission\n";
		case 0x01:	return "Echo\n";
		case 0x02:	return "Reconnection\n";
		case 0x03:	return "Suppress Go Ahead\n";
		case 0x04:	return "Approx Message Size Negotiation\n";
		case 0x05:	return "Status\n";
		case 0x06:	return "Timing Mark\n";
		case 0x07:	return "Remote Controlled Trans and Echo\n";
		case 0x08:	return "Output Line Width\n";
		case 0x09:	return "Output Page Size\n";
		case 0x0a:	return "Output Carriage-Return Disposition\n";
		case 0x0b:	return "Output Horizontal Tab Stops\n";
		case 0x0c:	return "Output Horizontal Tab Disposition\n";
		case 0x0d:	return "Output Formfeed Disposition\n";
		case 0x0e:	return "Output Vertical Tabstops\n";
		case 0x0f:	return "Output Vertical Tab Disposition\n";
		case 0x10:	return "Output Linefeed Disposition\n";
		case 0x11:	return "Extended ASCII\n";
		case 0x12:	return "Logout\n";
		case 0x13:	return "Byte Macro\n";
		case 0x14:	return "Data Entry Terminal\n";
		case 0x15:	return "SUPDUP\n";
		case 0x16:	return "SUPDUP Output\n";
		case 0x17:	return "Send Location\n";
		case 0x18:	return "Terminal Type\n";
		case 0x19:	return "End of Record\n";
		case 0x1a:	return "TACACS User Identification\n";
		case 0x1b:	return "Output Marking\n";
		case 0x1c:	return "Terminal Location Number\n";
		case 0x1d:	return "Telnet 3270 Regime\n";
		case 0x1e:	return "X.3 PAD\n";
		case 0x1f:	return "Negotiate About Window Size\n";
		case 0x20:	return "Terminal Speed\n";
		case 0x21:	return "Remote Flow Control\n";
		case 0x22:	return "Linemode\n";
		case 0x23:	return "X Display Location\n";
		case (byte) 0xff:	return "Extended-Options-List\n";
		default:	return "unknown option\n";
		}
	}

}