📄 dhcpoption.java
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* DHO_STDA_SERVER(76)
* DHO_NDS_SERVERS(85)
* </pre>
*
* @param code the option code.
* @param val the value array
* @throws IllegalArgumentException the option code is not in the list above.
*/
public static DHCPOption newOptionAsInetAddresses(byte code, InetAddress[] val) {
if (!isOptionAsInetAddrs(code)) {
throw new IllegalArgumentException("DHCP option type ("+code+") is not InetAddresses");
}
return new DHCPOption(code, inetAddresses2Bytes(val));
}
/**
* Creates a DHCP Option as String format.
*
* <p>This method is only allowed for the following option codes:
* <pre>
* DHO_HOST_NAME(12)
* DHO_MERIT_DUMP(14)
* DHO_DOMAIN_NAME(15)
* DHO_ROOT_PATH(17)
* DHO_EXTENSIONS_PATH(18)
* DHO_NETBIOS_SCOPE(47)
* DHO_DHCP_MESSAGE(56)
* DHO_VENDOR_CLASS_IDENTIFIER(60)
* DHO_NWIP_DOMAIN_NAME(62)
* DHO_NIS_DOMAIN(64)
* DHO_NIS_SERVER(65)
* DHO_TFTP_SERVER(66)
* DHO_BOOTFILE(67)
* DHO_NDS_TREE_NAME(86)
* DHO_USER_AUTHENTICATION_PROTOCOL(98)
* </pre>
*
* @param code the option code.
* @param val the value
* @throws IllegalArgumentException the option code is not in the list above.
*/
public static DHCPOption newOptionAsString(byte code, String val) {
if (!isOptionAsString(code)) {
throw new IllegalArgumentException("DHCP option type ("+code+") is not string");
}
return new DHCPOption(code, DHCPPacket.stringToBytes(val));
}
/**
* Get the option value based on the context, i.e. the client's request.
*
* <p>This should be the only method used with this class to get relevant values.
*
* @param request the client's DHCP requets
* @return the value of the specific option in the client request
* @throws NullPointerException if <tt>request</tt> is <tt>null</tt>.
*/
public DHCPOption applyOption(DHCPPacket request) {
if (request == null) {
throw new NullPointerException("request is null");
}
if (this.mirror) {
DHCPOption res = request.getOption(this.getCode());
return (res != null ? res : this); // return res or this
} else {
return this;
}
}
/**
* Appends to this string builder a detailed string representation of the DHCP datagram.
*
* <p>This multi-line string details: the static, options and padding parts
* of the object. This is useful for debugging, but not efficient.
*
* @param buffer the string builder the string representation of this object should be appended.
*/
public void append(StringBuilder buffer) {
// check for readable option name
if (_DHO_NAMES.containsKey(this.code)) {
buffer.append(_DHO_NAMES.get(this.code));
}
buffer.append('(')
.append(unsignedByte(this.code))
.append(")=");
if (this.mirror) {
buffer.append("<mirror>");
}
// check for value printing
if (this.value == null) {
buffer.append("<null>");
} else if (this.code == DHO_DHCP_MESSAGE_TYPE) {
Byte cmd = this.getValueAsByte();
if (_DHCP_CODES.containsKey(cmd)) {
buffer.append(_DHCP_CODES.get(cmd));
} else {
buffer.append(cmd);
}
} else if (this.code == DHO_USER_CLASS) {
buffer.append(userClassToString(this.value));
} else if (this.code == DHO_DHCP_AGENT_OPTIONS) {
buffer.append(agentOptionsToString(this.value));
} else if (_DHO_FORMATS.containsKey(this.code)) {
// formatted output
try { // catch malformed values
switch (_DHO_FORMATS.get(this.code)) {
case INET:
DHCPPacket.appendHostAddress(buffer, this.getValueAsInetAddr());
break;
case INETS:
for (InetAddress addr : this.getValueAsInetAddrs()) {
DHCPPacket.appendHostAddress(buffer, addr);
buffer.append(' ');
}
break;
case INT:
buffer.append(this.getValueAsInt());
break;
case SHORT:
buffer.append(this.getValueAsShort());
break;
case SHORTS:
for (short aShort : this.getValueAsShorts()) {
buffer.append(aShort)
.append(' ');
}
break;
case BYTE:
buffer.append(this.getValueAsByte());
break;
case STRING:
buffer.append('"')
.append(this.getValueAsString())
.append('"');
break;
case BYTES:
if (this.value != null) {
for (byte aValue : this.value) {
buffer.append(unsignedByte(aValue))
.append(' ');
}
}
break;
default:
buffer.append("0x");
DHCPPacket.appendHex(buffer, this.value);
break;
}
} catch (IllegalArgumentException e) {
// fallback to bytes
buffer.append("0x");
DHCPPacket.appendHex(buffer, this.value);
}
} else {
// unformatted raw output
buffer.append("0x");
DHCPPacket.appendHex(buffer, this.value);
}
}
/**
* Returns a detailed string representation of the DHCP datagram.
*
* <p>This multi-line string details: the static, options and padding parts
* of the object. This is useful for debugging, but not efficient.
*
* @return a string representation of the object.
*/
@Override
public String toString() {
StringBuilder s = new StringBuilder();
this.append(s);
return s.toString();
}
/**
* Convert unsigned byte to int
*/
private static int unsignedByte(byte b) {
return (b & 0xFF);
}
/**************************************************************************
*
* Type converters.
*
**************************************************************************/
public static byte[] byte2Bytes(byte val) {
byte[] raw = { val };
return raw;
}
public static byte[] short2Bytes(short val) {
byte[] raw = { (byte) ((val & 0xFF00) >>> 8), (byte) (val & 0XFF) };
return raw;
}
public static byte[] int2Bytes(int val) {
byte[] raw = { (byte) ((val & 0xFF000000) >>> 24),
(byte) ((val & 0X00FF0000) >>> 16),
(byte) ((val & 0x0000FF00) >>> 8),
(byte) ((val & 0x000000FF) ) };
return raw;
}
public static byte[] inetAddress2Bytes(InetAddress val) {
if (val == null){
return null;
}
if (!(val instanceof Inet4Address)) {
throw new IllegalArgumentException("Adress must be of subclass Inet4Address");
}
return val.getAddress();
}
public static byte[] inetAddresses2Bytes(InetAddress[] val) {
if (val == null) {
return null;
}
byte[] buf = new byte[val.length * 4];
for (int i=0; i<val.length; i++) {
InetAddress addr = val[i];
if (!(addr instanceof Inet4Address)) {
throw new IllegalArgumentException("Adress must be of subclass Inet4Address");
}
System.arraycopy(addr.getAddress(), 0, buf, i*4, 4);
}
return buf;
}
/**
* Convert DHO_USER_CLASS (77) option to a List.
*
* @param buf option value of type User Class.
* @return List of String values.
*/
public static List<String> userClassToList(byte[] buf) {
if (buf == null) {
return null;
}
LinkedList<String> list = new LinkedList<String>();
int i=0;
while (i<buf.length) {
int size = unsignedByte(buf[i++]);
int instock = buf.length - i;
if (size > instock) {
size = instock;
}
list.add(DHCPPacket.bytesToString(buf, i, size));
i += size;
}
return list;
}
/**
* Converts DHO_USER_CLASS (77) option to a printable string
*
* @param buf option value of type User Class.
* @return printable string.
*/
public static String userClassToString(byte[] buf) {
if (buf == null) {
return null;
}
List list = userClassToList(buf);
Iterator it = list.iterator();
StringBuffer s = new StringBuffer();
while (it.hasNext()) {
s.append('"').append((String) it.next()).append('"');
if (it.hasNext()) {
s.append(',');
}
}
return s.toString();
}
/**
* Converts this list of strings to a DHO_USER_CLASS (77) option.
*
* @param list the list of strings
* @return byte[] buffer to use with <tt>setOptionRaw</tt>, <tt>null</tt> if list is null
* @throws IllegalArgumentException if List contains anything else than String
*/
public static byte[] stringListToUserClass(List<String> list) {
if (list == null) { return null; }
ByteArrayOutputStream buf = new ByteArrayOutputStream(32);
DataOutputStream out = new DataOutputStream(buf);
try {
for (String s : list) {
byte[] bytes = DHCPPacket.stringToBytes(s);
int size = bytes.length;
if (size > 255) { size = 255; }
out.writeByte(size);
out.write(bytes, 0, size);
}
return buf.toByteArray();
} catch (IOException e) {
logger.log(Level.SEVERE, "Unexpected IOException", e);
return buf.toByteArray();
}
}
/**
* Converts DHO_DHCP_AGENT_OPTIONS (82) option type to a printable string
*
* @param buf option value of type Agent Option.
* @return printable string.
*/
public static String agentOptionsToString(byte[] buf) {
if (buf == null) {
return null;
}
Map<Byte, String> map = agentOptionsToMap(buf);
StringBuffer s = new StringBuffer();
for (Entry<Byte, String> entry : map.entrySet()) {
s.append('{').append(unsignedByte(entry.getKey())).append("}\"");
s.append(entry.getValue()).append('\"');
s.append(',');
}
if (s.length() > 0) {
s.setLength(s.length() - 1);
}
return s.toString();
}
/**
* Converts Map<Byte,String> to DHO_DHCP_AGENT_OPTIONS (82) option.
*
* <p>LinkedHashMap are preferred as they preserve insertion order. Regular
* HashMap order is randon.
*
* @param map Map<Byte,String> couples
* @return byte[] buffer to use with <tt>setOptionRaw</tt>
* @throws IllegalArgumentException if List contains anything else than String
*/
public static byte[] agentOptionToRaw(Map<Byte, String> map) {
if (map == null) {
return null;
}
ByteArrayOutputStream buf = new ByteArrayOutputStream(64);
DataOutputStream out = new DataOutputStream(buf);
try {
for (Entry<Byte, String> entry : map.entrySet()) {
byte[] bufTemp = DHCPPacket.stringToBytes(entry.getValue());
int size = bufTemp.length;
assert (size >= 0);
if (size > 255) {
throw new IllegalArgumentException("Value size is greater then 255 bytes");
}
out.writeByte(entry.getKey());
out.writeByte(size);
out.write(bufTemp, 0, size);
}
return buf.toByteArray();
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