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This OSGi bundle wraps ${pkgArtifactId} ${pkgVersion} jar file.
// SPDX-License-Identifier: BSD-3-Clause
// Copyright (c) 1999-2004 Brian Wellington ([email protected])
package org.xbill.DNS;
import java.io.IOException;
import java.util.Arrays;
/**
* DNS extension options, as described in RFC 6891. The rdata of an OPT record is defined as a list
* of options; this represents a single option.
*
* @author Brian Wellington
* @author Ming Zhou <[email protected]>, Beaumaris Networks
*/
public abstract class EDNSOption {
/**
* @see IANA
* DNS EDNS0 Option Codes (OPT)
*/
public static class Code {
private Code() {}
/** Apple's DNS Long-Lived Queries protocol, draft-sekar-dns-llq-06 */
public static final int LLQ = 1;
/** Dynamic DNS Update Leases, draft-sekar-dns-ul-02 */
public static final int UL = 2;
/** Name Server Identifier, RFC 5001 */
public static final int NSID = 3;
/** DNSSEC Algorithm Understood (DAU), RFC 6975 */
public static final int DAU = 5;
/** DNSSEC DS Hash Understood (DHU), RFC 6975 */
public static final int DHU = 6;
/** DNSSEC NSEC3 Hash Understood (N3U), RFC 6975 */
public static final int N3U = 7;
/** Client Subnet, RFC 7871 */
public static final int CLIENT_SUBNET = 8;
/** (EDNS) EXPIRE Option, RFC 7314 */
public static final int EDNS_EXPIRE = 9;
/** Cookie, RFC 7873 */
public static final int COOKIE = 10;
/** TCP Keepalive, RFC 7828 */
public static final int TCP_KEEPALIVE = 11;
/** EDNS(0) Padding Option, RFC 7830 */
public static final int PADDING = 12;
/** CHAIN Query Requests in DNS, RFC 7901 */
public static final int CHAIN = 13;
/** Signaling Trust Anchor Knowledge in DNS Security Extensions (DNSSEC), RFC 8145 */
public static final int EDNS_KEY_TAG = 14;
/** Extended DNS Errors, RFC 8914. */
public static final int EDNS_EXTENDED_ERROR = 15;
/** DNS EDNS Tags, draft-bellis-dnsop-edns-tags-01 */
public static final int EDNS_CLIENT_TAG = 16;
/** DNS EDNS Tags, draft-bellis-dnsop-edns-tags-01 */
public static final int EDNS_SERVER_TAG = 17;
private static final Mnemonic codes =
new Mnemonic("EDNS Option Codes", Mnemonic.CASE_SENSITIVE);
static {
codes.setMaximum(0xFFFF);
codes.setPrefix("CODE");
codes.setNumericAllowed(true);
codes.add(LLQ, "LLQ");
codes.add(UL, "UL");
codes.add(NSID, "NSID");
codes.add(DAU, "DAU");
codes.add(DHU, "DHU");
codes.add(N3U, "N3U");
codes.add(CLIENT_SUBNET, "edns-client-subnet");
codes.add(EDNS_EXPIRE, "EDNS_EXPIRE");
codes.add(COOKIE, "COOKIE");
codes.add(TCP_KEEPALIVE, "edns-tcp-keepalive");
codes.add(PADDING, "Padding");
codes.add(CHAIN, "CHAIN");
codes.add(EDNS_KEY_TAG, "edns-key-tag");
codes.add(EDNS_EXTENDED_ERROR, "Extended_DNS_Error");
codes.add(EDNS_CLIENT_TAG, "EDNS-Client-Tag");
codes.add(EDNS_SERVER_TAG, "EDNS-Server-Tag");
}
/** Converts an EDNS Option Code into its textual representation */
public static String string(int code) {
return codes.getText(code);
}
/**
* Converts a textual representation of an EDNS Option Code into its numeric value.
*
* @param s The textual representation of the option code
* @return The option code, or -1 on error.
*/
public static int value(String s) {
return codes.getValue(s);
}
}
private final int code;
/** Creates an option with the given option code and data. */
public EDNSOption(int code) {
this.code = Record.checkU16("code", code);
}
@Override
public String toString() {
return "{" + Code.string(code) + ": " + optionToString() + "}";
}
/**
* Returns the EDNS Option's code.
*
* @return the option code
*/
public int getCode() {
return code;
}
/**
* Returns the EDNS Option's data, as a byte array.
*
* @return the option data
*/
byte[] getData() {
DNSOutput out = new DNSOutput();
optionToWire(out);
return out.toByteArray();
}
/**
* Converts the wire format of an EDNS Option (the option data only) into the type-specific
* format.
*
* @param in The input Stream.
*/
abstract void optionFromWire(DNSInput in) throws IOException;
/**
* Converts the wire format of an EDNS Option (including code and length) into the type-specific
* format.
*
* @param in The input stream.
*/
static EDNSOption fromWire(DNSInput in) throws IOException {
int code, length;
code = in.readU16();
length = in.readU16();
if (in.remaining() < length) {
throw new WireParseException("truncated option");
}
int save = in.saveActive();
in.setActive(length);
EDNSOption option;
switch (code) {
case Code.NSID:
option = new NSIDOption();
break;
case Code.CLIENT_SUBNET:
option = new ClientSubnetOption();
break;
case Code.DAU:
case Code.DHU:
case Code.N3U:
option = new DnssecAlgorithmOption(code);
break;
case Code.COOKIE:
option = new CookieOption();
break;
case Code.TCP_KEEPALIVE:
option = new TcpKeepaliveOption();
break;
case Code.EDNS_EXTENDED_ERROR:
option = new ExtendedErrorCodeOption();
break;
default:
option = new GenericEDNSOption(code);
break;
}
option.optionFromWire(in);
in.restoreActive(save);
return option;
}
/**
* Converts the wire format of an EDNS Option (including code and length) into the type-specific
* format.
*
* @return The option, in wire format.
*/
public static EDNSOption fromWire(byte[] b) throws IOException {
return fromWire(new DNSInput(b));
}
/**
* Converts an EDNS Option (the type-specific option data only) into wire format.
*
* @param out The output stream.
*/
abstract void optionToWire(DNSOutput out);
/**
* Converts an EDNS Option (including code and length) into wire format.
*
* @param out The output stream.
*/
void toWire(DNSOutput out) {
out.writeU16(code);
int lengthPosition = out.current();
out.writeU16(0); /* until we know better */
optionToWire(out);
int length = out.current() - lengthPosition - 2;
out.writeU16At(length, lengthPosition);
}
/**
* Converts an EDNS Option (including code and length) into wire format.
*
* @return The option, in wire format.
*/
public byte[] toWire() {
DNSOutput out = new DNSOutput();
toWire(out);
return out.toByteArray();
}
/**
* Determines if two EDNS Options are identical.
*
* @param arg The option to compare to
* @return true if the options are equal, false otherwise.
*/
@Override
public boolean equals(Object arg) {
if (!(arg instanceof EDNSOption)) {
return false;
}
EDNSOption opt = (EDNSOption) arg;
if (code != opt.code) {
return false;
}
return Arrays.equals(getData(), opt.getData());
}
/** Generates a hash code based on the EDNS Option's data. */
@Override
public int hashCode() {
byte[] array = getData();
int hashval = 0;
for (byte b : array) {
hashval += (hashval << 3) + (b & 0xFF);
}
return hashval;
}
abstract String optionToString();
}
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