Message(DNSInput in) throws IOException {
this(new Header(in));
boolean isUpdate = (header.getOpcode() == Opcode.UPDATE);
boolean truncated = header.getFlag(Flags.TC);
try {
for (int i = 0; i < 4; i++) {
int count = header.getCount(i);
if (count > 0) sections[i] = new ArrayList(count);
for (int j = 0; j < count; j++) {
int pos = in.current();
Record rec = Record.fromWire(in, i, isUpdate);
sections[i].add(rec);
if (i == Section.ADDITIONAL) {
if (rec.getType() == Type.TSIG) tsigstart = pos;
if (rec.getType() == Type.SIG) {
SIGRecord sig = (SIGRecord) rec;
if (sig.getTypeCovered() == 0) sig0start = pos;
}
}
}
}
} catch (WireParseException e) {
if (!truncated) throw e;
}
size = in.current();
}
/**
* Determines if an RRset with the given name and type is already present in the given section.
*
* @see RRset
* @see Section
*/
public boolean findRRset(Name name, int type, int section) {
if (sections[section] == null) return false;
for (int i = 0; i < sections[section].size(); i++) {
Record r = (Record) sections[section].get(i);
if (r.getType() == type && name.equals(r.getName())) return true;
}
return false;
}
private final void maybeAddRecord(Record record) throws IOException {
int rtype = record.getType();
Name name = record.getName();
if (rtype == Type.SOA && !name.equals(origin)) {
throw new IOException("SOA owner " + name + " does not match zone origin " + origin);
}
if (name.subdomain(origin)) addRecord(record);
}
private final void maybeAddRecord(Record record, Cache cache, Object source) throws IOException {
int type = record.getType();
Name name = record.getName();
if (type == Type.SOA) {
if (!name.equals(origin))
throw new IOException("SOA owner " + name + " does not match zone origin " + origin);
else {
setOrigin(origin);
dclass = record.getDClass();
}
}
if (origin == null && type != Type.SOA)
throw new IOException("non-SOA record seen at " + name + " with no origin set");
if (name.subdomain(origin)) addRecord(record);
else if (cache != null) cache.addRecord(record, Credibility.GLUE, source);
}
/**
* Converts the given section of the Message to a String.
*
* @see Section
*/
public String sectionToString(int i) {
if (i > 3) return null;
StringBuffer sb = new StringBuffer();
Record[] records = getSectionArray(i);
for (int j = 0; j < records.length; j++) {
Record rec = records[j];
if (i == Section.QUESTION) {
sb.append(";;\t" + rec.name);
sb.append(", type = " + Type.string(rec.type));
sb.append(", class = " + DClass.string(rec.dclass));
} else if (rec.getType() == Type.OPT) continue;
else sb.append(rec);
sb.append("\n");
}
return sb.toString();
}
private int uniqueID(Message m) {
Record r = m.getQuestion();
return (((r.getName().hashCode() & 0xFFFF) << 16)
+ (r.getType() + hashCode() << 8)
+ (hashCode() & 0xFF));
}
public static Record[] getRecords(String namestr, short type, short dclass, byte cred) {
Message query;
Message response;
Record question;
Record[] answers;
int answerCount = 0, i = 0;
Enumeration e;
Name name = new Name(namestr);
/*System.out.println("lookup of " + name + " " + Type.string(type));*/
if (!Type.isRR(type) && type != Type.ANY) return null;
if (res == null) {
try {
eres = new ExtendedResolver();
} catch (UnknownHostException uhe) {
System.out.println("Failed to initialize resolver");
System.exit(-1);
}
}
if (cache == null) cache = new Cache();
CacheResponse cached = cache.lookupRecords(name, type, dclass, cred);
/*System.out.println(cached);*/
if (cached.isSuccessful()) {
RRset rrset = cached.answer();
answerCount = rrset.size();
e = rrset.rrs();
} else if (cached.isNegative()) {
answerCount = 0;
e = null;
} else {
question = Record.newRecord(name, type, dclass);
query = Message.newQuery(question);
if (res != null) response = res.send(query);
else response = eres.send(query);
short rcode = response.getHeader().getRcode();
if (rcode == Rcode.NOERROR || rcode == Rcode.NXDOMAIN) cache.addMessage(response);
if (rcode != Rcode.NOERROR) return null;
e = response.getSection(Section.ANSWER);
while (e.hasMoreElements()) {
Record r = (Record) e.nextElement();
if (matchType(r.getType(), type)) answerCount++;
}
e = response.getSection(Section.ANSWER);
}
if (answerCount == 0) return null;
answers = new Record[answerCount];
while (e.hasMoreElements()) {
Record r = (Record) e.nextElement();
if (matchType(r.getType(), type)) answers[i++] = r;
}
return answers;
}
/**
* Sends a message to a single server and waits for a response. No checking is done to ensure that
* the response is associated with the query.
*
* @param query The query to send.
* @return The response.
* @throws IOException An error occurred while sending or receiving.
*/
public Message send(Message query) throws IOException {
if (Options.check("verbose"))
System.err.println(
"Sending to " + address.getAddress().getHostAddress() + ":" + address.getPort());
if (query.getHeader().getOpcode() == Opcode.QUERY) {
Record question = query.getQuestion();
if (question != null && question.getType() == Type.AXFR) return sendAXFR(query);
}
query = (Message) query.clone();
applyEDNS(query);
if (tsig != null) {
tsig.apply(query, null);
}
byte[] out = query.toWire(Message.MAXLENGTH);
int udpSize = maxUDPSize(query);
boolean tcp = false;
long endTime = System.currentTimeMillis() + timeoutValue;
do {
byte[] b_in;
if (useTCP || out.length > udpSize) {
tcp = true;
}
if (tcp) {
b_in = TCPClient.sendrecv(localAddress, address, out, endTime);
} else {
b_in = UDPClient.sendrecv(localAddress, address, out, udpSize, endTime);
}
/*
* Check that the response is long enough.
*/
if (b_in.length < Header.LENGTH) {
throw new WireParseException("invalid DNS header - " + "too short");
}
/*
* Check that the response ID matches the query ID. We want
* to check this before actually parsing the message, so that
* if there's a malformed response that's not ours, it
* doesn't confuse us.
*/
int id = ((b_in[0] & 0xFF) << 8) + (b_in[1] & 0xFF);
int qid = query.getHeader().getID();
if (id != qid) {
String error = "invalid message id: expected " + qid + "; got id " + id;
if (tcp) {
throw new WireParseException(error);
} else {
if (Options.check("verbose")) {
System.err.println(error);
}
continue;
}
}
Message response = parseMessage(b_in);
verifyTSIG(query, response, b_in, tsig);
if (!tcp && !ignoreTruncation && response.getHeader().getFlag(Flags.TC)) {
tcp = true;
continue;
}
return response;
} while (true);
}
