Detailed changes
@@ -5,8 +5,19 @@ package de.measite.minidns;
*/
public interface DNSCache {
+ /**
+ * Add an an dns answer/response for a given dns question. Implementations
+ * should honor the ttl / receive timestamp.
+ * @param q The question.
+ * @param message The dns message.
+ */
void put(Question q, DNSMessage message);
+ /**
+ * Request a cached dns response.
+ * @param q The dns question.
+ * @return The dns message.
+ */
DNSMessage get(Question q);
}
@@ -4,39 +4,89 @@ import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
+import java.util.Arrays;
import de.measite.minidns.Record.CLASS;
import de.measite.minidns.Record.TYPE;
import de.measite.minidns.util.NameUtil;
+/**
+ * A DNS question (request).
+ */
public class Question {
+ /**
+ * The question string (e.g. "measite.de").
+ */
private final String name;
+ /**
+ * The question type (e.g. A).
+ */
private final TYPE type;
+ /**
+ * The question class (usually IN / internet).
+ */
private final CLASS clazz;
+ /**
+ * Cache for the serialized object.
+ */
private byte[] byteArray;
+ /**
+ * Create a dns question for the given name/type/class.
+ * @param name The name e.g. "measite.de".
+ * @param type The type, e.g. A.
+ * @param clazz The class, usually IN (internet).
+ */
public Question(String name, TYPE type, CLASS clazz) {
this.name = name;
this.type = type;
this.clazz = clazz;
}
+ /**
+ * Create a dns question for the given name/type/IN (internet class).
+ * @param name The name e.g. "measite.de".
+ * @param type The type, e.g. A.
+ */
+ public Question(String name, TYPE type) {
+ this(name, type, CLASS.IN);
+ }
+
+ /**
+ * Retrieve the type of this question.
+ * @return The type.
+ */
public TYPE getType() {
return type;
}
+ /**
+ * Retrieve the class of this dns question (usually internet).
+ * @return The class of this dns question.
+ */
public CLASS getClazz() {
return clazz;
}
+ /**
+ * Retrieve the name of this dns question (e.g. "measite.de").
+ * @return The name of this dns question.
+ */
public String getName() {
return name;
}
+ /**
+ * Parse a byte array and rebuild the dns question from it.
+ * @param dis The input stream.
+ * @param data The plain data (for dns name references).
+ * @return The parsed dns question.
+ * @throws IOException On errors (read outside of packet).
+ */
public static Question parse(DataInputStream dis, byte[] data) throws IOException {
String name = NameUtil.parse(dis, data);
TYPE type = TYPE.getType(dis.readUnsignedShort());
@@ -44,6 +94,10 @@ public class Question {
return new Question (name, type, clazz);
}
+ /**
+ * Generate a binary paket for this dns question.
+ * @return The dns question.
+ */
public byte[] toByteArray() {
if (byteArray == null) {
ByteArrayOutputStream baos = new ByteArrayOutputStream(512);
@@ -65,7 +119,7 @@ public class Question {
@Override
public int hashCode() {
- return toByteArray().hashCode();
+ return Arrays.hashCode(toByteArray());
}
@Override
@@ -76,6 +130,8 @@ public class Question {
if (!(other instanceof Question)) {
return false;
}
- return this.hashCode() == other.hashCode();
+ byte t[] = toByteArray();
+ byte o[] = ((Question)other).toByteArray();
+ return Arrays.equals(t, o);
}
}
@@ -286,10 +286,18 @@ public class Record {
(q.getName().equals(name));
}
+ /**
+ * The generic record name, e.g. "measite.de".
+ * @return The record name.
+ */
public String getName() {
return name;
}
+ /**
+ * The payload data, usually a subclass of data (A, AAAA, CNAME, ...).
+ * @return The payload data.
+ */
public Data getPayload() {
return payloadData;
}
@@ -5,8 +5,14 @@ import java.io.IOException;
import de.measite.minidns.Record.TYPE;
+/**
+ * A record payload (ip pointer).
+ */
public class A implements Data {
+ /**
+ * Target IP.
+ */
private byte[] ip;
@Override
@@ -5,8 +5,14 @@ import java.io.IOException;
import de.measite.minidns.Record.TYPE;
+/**
+ * AAAA payload (an ipv6 pointer).
+ */
public class AAAA implements Data {
+ /**
+ * The ipv6 address.
+ */
private byte[] ip;
@Override
@@ -6,6 +6,9 @@ import java.io.IOException;
import de.measite.minidns.Record.TYPE;
import de.measite.minidns.util.NameUtil;
+/**
+ * CNAME payload (pointer to another domain / address).
+ */
public class CNAME implements Data {
protected String name;
@@ -20,8 +23,7 @@ public class CNAME implements Data {
@Override
public byte[] toByteArray() {
- // TODO Auto-generated method stub
- return null;
+ throw new UnsupportedOperationException("Not implemented yet");
}
@Override
@@ -5,12 +5,30 @@ import java.io.IOException;
import de.measite.minidns.Record.TYPE;
+/**
+ * Generic payload class.
+ */
public interface Data {
+ /**
+ * The payload type.
+ * @return The payload type.
+ */
TYPE getType();
+ /**
+ * Binary representation of this payload.
+ * @return The binary representation of this payload.
+ */
byte[] toByteArray();
+ /**
+ * Parse this payload.
+ * @param dis The input stream.
+ * @param data The plain data (needed for name cross references).
+ * @param length The payload length.
+ * @throws IOException on io error (read past paket boundary).
+ */
void parse(DataInputStream dis, byte data[], int length) throws IOException;
}
@@ -2,6 +2,9 @@ package de.measite.minidns.record;
import de.measite.minidns.Record.TYPE;
+/**
+ * Nameserver record.
+ */
public class NS extends CNAME {
@Override
@@ -6,49 +6,99 @@ import java.io.IOException;
import de.measite.minidns.Record.TYPE;
import de.measite.minidns.util.NameUtil;
+/**
+ * SRV record payload (service pointer).
+ */
public class SRV implements Data {
+ /**
+ * The priority of this service.
+ */
protected int priority;
+
+ /**
+ * The weight of this service.
+ */
protected int weight;
+
+ /**
+ * The target port.
+ */
protected int port;
+
+ /**
+ * The target server.
+ */
protected String name;
+ /**
+ * The priority of this service. Lower values mean higher priority.
+ * @return The priority.
+ */
public int getPriority() {
return priority;
}
+ /**
+ * Set the priority of this service entry. Lower values have higher priority.
+ * @param priority The new priority.
+ */
public void setPriority(int priority) {
this.priority = priority;
}
+ /**
+ * The weight of this service. Services with the same priority should be
+ * balanced based on weight.
+ * @return The weight of this service.
+ */
public int getWeight() {
return weight;
}
+ /**
+ * Set the weight of this service.
+ * @param weight The new weight of this service.
+ */
public void setWeight(int weight) {
this.weight = weight;
}
+ /**
+ * The target port of this service.
+ * @return The target port of this service.
+ */
public int getPort() {
return port;
}
+ /**
+ * Set the target port of this service.
+ * @param port The new target port.
+ */
public void setPort(int port) {
this.port = port;
}
+ /**
+ * The name of the target server.
+ * @return The target servers name.
+ */
public String getName() {
return name;
}
+ /**
+ * Set the name of the target server.
+ * @param name The new target servers name.
+ */
public void setName(String name) {
this.name = name;
}
@Override
public byte[] toByteArray() {
- // TODO Auto-generated method stub
- return null;
+ throw new UnsupportedOperationException("Not implemented yet");
}
@Override
@@ -8,12 +8,28 @@ import java.net.IDN;
import java.util.HashSet;
import java.util.Arrays;
+/**
+ * Utilities related to internationalized domain names and dns name handling.
+ */
public class NameUtil {
+ /**
+ * Retrieve the rough binary length of a string
+ * (length + 2 bytes length prefix).
+ * @param name The name string.
+ * @return The binary size of the string (length + 2).
+ */
public static int size(String name) {
return name.length() + 2;
}
+ /**
+ * Check if two internationalized domain names are equal, possibly causing
+ * a serialization of both domain names.
+ * @param name1 The first domain name.
+ * @param name2 The second domain name.
+ * @return True if both domain names are the same.
+ */
public static boolean idnEquals(String name1, String name2) {
if (name1 == name2) return true; // catches null, null
if (name1 == null) return false;
@@ -27,6 +43,12 @@ public class NameUtil {
}
}
+ /**
+ * Serialize a domain name under IDN rules.
+ * @param name The domain name.
+ * @return The binary domain name representation.
+ * @throws IOException Should never happen.
+ */
public static byte[] toByteArray(String name) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream(64);
DataOutputStream dos = new DataOutputStream(baos);
@@ -38,8 +60,16 @@ public class NameUtil {
dos.writeByte(0);
dos.flush();
return baos.toByteArray();
- }
+ }
+ /**
+ * Parse a domain name starting at the current offset and moving the input
+ * stream pointer past this domain name (even if cross references occure).
+ * @param dis The input stream.
+ * @param data The raw data (for cross references).
+ * @return The domain name string.
+ * @throws IOException Should never happen.
+ */
public static String parse(DataInputStream dis, byte data[])
throws IOException
{
@@ -63,6 +93,14 @@ public class NameUtil {
return s;
}
+ /**
+ * Parse a domain name starting at the given offset.
+ * @param data The raw data.
+ * @param offset The offset.
+ * @param jumps The list of jumps (by now).
+ * @return The parsed domain name.
+ * @throws IllegalStateException on cycles.
+ */
public static String parse(
byte data[],
int offset,