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-rw-r--r--src/de/measite/minidns/Record.java293
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diff --git a/src/de/measite/minidns/Record.java b/src/de/measite/minidns/Record.java
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+package de.measite.minidns;
+
+import java.io.DataInputStream;
+import java.io.IOException;
+import java.util.HashMap;
+
+import de.measite.minidns.record.A;
+import de.measite.minidns.record.AAAA;
+import de.measite.minidns.record.CNAME;
+import de.measite.minidns.record.Data;
+import de.measite.minidns.record.NS;
+import de.measite.minidns.record.SRV;
+import de.measite.minidns.util.NameUtil;
+
+/**
+ * A generic DNS record.
+ */
+public class Record {
+
+ /**
+ * The record type.
+ * {@see http://www.iana.org/assignments/dns-parameters}
+ */
+ public static enum TYPE {
+ A(1),
+ NS(2),
+ MD(3),
+ MF(4),
+ CNAME(5),
+ SOA(6),
+ MB(7),
+ MG(8),
+ MR(9),
+ NULL(10),
+ WKS(11),
+ PTR(12),
+ HINFO(13),
+ MINFO(14),
+ MX(15),
+ TXT(16),
+ RP(17),
+ AFSDB(18),
+ X25(19),
+ ISDN(20),
+ RT(21),
+ NSAP(22),
+ NSAP_PTR(23),
+ SIG(24),
+ KEY(25),
+ PX(26),
+ GPOS(27),
+ AAAA(28),
+ LOC(29),
+ NXT(30),
+ EID(31),
+ NIMLOC(32),
+ SRV(33),
+ ATMA(34),
+ NAPTR(35),
+ KX(36),
+ CERT(37),
+ A6(38),
+ DNAME(39),
+ SINK(40),
+ OPT(41),
+ APL(42),
+ DS(43),
+ SSHFP(44),
+ IPSECKEY(45),
+ RRSIG(46),
+ NSEC(47),
+ DNSKEY(48),
+ DHCID(49),
+ NSEC3(50),
+ NSEC3PARAM(51),
+ HIP(55),
+ NINFO(56),
+ RKEY(57),
+ TALINK(58),
+ SPF(99),
+ UINFO(100),
+ UID(101),
+ GID(102),
+ TKEY(249),
+ TSIG(250),
+ IXFR(251),
+ AXFR(252),
+ MAILB(253),
+ MAILA(254),
+ ANY(255),
+ TA(32768),
+ DLV(32769);
+
+ /**
+ * The value of this DNS record type.
+ */
+ private final int value;
+
+ /**
+ * Internal lookup table to map values to types.
+ */
+ private final static HashMap<Integer, TYPE> INVERSE_LUT =
+ new HashMap<Integer, TYPE>();
+
+ /**
+ * Initialize the reverse lookup table.
+ */
+ static {
+ for(TYPE t: TYPE.values()) {
+ INVERSE_LUT.put(t.getValue(), t);
+ }
+ }
+
+ /**
+ * Create a new record type.
+ * @param value The binary value of this type.
+ */
+ private TYPE(int value) {
+ this.value = value;
+ }
+
+ /**
+ * Retrieve the binary value of this type.
+ * @return The binary value.
+ */
+ public int getValue() {
+ return value;
+ }
+
+ /**
+ * Retrieve the symbolic type of the binary value.
+ * @param value The binary type value.
+ * @return The symbolic tpye.
+ */
+ public static TYPE getType(int value) {
+ return INVERSE_LUT.get(value);
+ }
+ };
+
+ /**
+ * The symbolic class of a DNS record (usually IN for Internet).
+ */
+ public static enum CLASS {
+ IN(1),
+ CH(3),
+ HS(4),
+ NONE(254),
+ ANY(255);
+
+ /**
+ * Internal reverse lookup table to map binary class values to symbolic
+ * names.
+ */
+ private final static HashMap<Integer, CLASS> INVERSE_LUT =
+ new HashMap<Integer, CLASS>();
+
+ /**
+ * Initialize the interal reverse lookup table.
+ */
+ static {
+ for(CLASS c: CLASS.values()) {
+ INVERSE_LUT.put(c.getValue(), c);
+ }
+ }
+
+ /**
+ * The binary value of this dns class.
+ */
+ private final int value;
+
+ /**
+ * Create a new DNS class based on a binary value.
+ * @param value The binary value of this DNS class.
+ */
+ private CLASS(int value) {
+ this.value = value;
+ }
+
+ /**
+ * Retrieve the binary value of this DNS class.
+ * @return The binary value of this DNS class.
+ */
+ public int getValue() {
+ return value;
+ }
+
+ /**
+ * Retrieve the symbolic DNS class for a binary class value.
+ * @param value The binary DNS class value.
+ * @return The symbolic class instance.
+ */
+ public static CLASS getClass(int value) {
+ return INVERSE_LUT.get(value);
+ }
+
+ }
+
+ /**
+ * The generic name of this record.
+ */
+ protected String name;
+
+ /**
+ * The type (and payload type) of this record.
+ */
+ protected TYPE type;
+
+ /**
+ * The record class (usually CLASS.IN).
+ */
+ protected CLASS clazz;
+
+ /**
+ * The ttl of this record.
+ */
+ protected long ttl;
+
+ /**
+ * The payload object of this record.
+ */
+ protected Data payloadData;
+
+ /**
+ * Parse a given record based on the full message data and the current
+ * stream position.
+ * @param dis The DataInputStream positioned at the first record byte.
+ * @param data The full message data.
+ * @throws IOException In case of malformed replies.
+ */
+ public void parse(DataInputStream dis, byte[] data) throws IOException {
+ this.name = NameUtil.parse(dis, data);
+ this.type = TYPE.getType(dis.readUnsignedShort());
+ this.clazz = CLASS.getClass(dis.readUnsignedShort());
+ this.ttl = (((long)dis.readUnsignedShort()) << 32) +
+ dis.readUnsignedShort();
+ int payloadLength = dis.readUnsignedShort();
+ switch (this.type) {
+ case SRV:
+ this.payloadData = new SRV();
+ break;
+ case AAAA:
+ this.payloadData = new AAAA();
+ break;
+ case A:
+ this.payloadData = new A();
+ break;
+ case NS:
+ this.payloadData = new NS();
+ break;
+ case CNAME:
+ this.payloadData = new CNAME();
+ break;
+ default:
+ System.out.println("Unparsed type " + type);
+ this.payloadData = null;
+ for (int i = 0; i < payloadLength; i++) {
+ dis.readByte();
+ }
+ break;
+ }
+ if (this.payloadData != null) {
+ this.payloadData.parse(dis, data, payloadLength);
+ }
+ }
+
+ /**
+ * Retrieve a textual representation of this resource record.
+ * @return String
+ */
+ @Override
+ public String toString() {
+ if (payloadData == null) {
+ return "RR " + type + "/" + clazz;
+ }
+ return "RR " + type + "/" + clazz + ": " + payloadData.toString();
+ };
+
+ /**
+ * Check if this record answers a given query.
+ * @param q The query.
+ * @return True if this record is a valid answer.
+ */
+ public boolean isAnswer(Question q) {
+ return ((q.getType() == type) || (q.getType() == TYPE.ANY)) &&
+ ((q.getClazz() == clazz) || (q.getClazz() == CLASS.ANY)) &&
+ (q.getName().equals(name));
+ }
+
+ public Data getPayload() {
+ return payloadData;
+ }
+
+}