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();
}
private Record parseRR(MyStringTokenizer st, boolean useLast, Record last, Name origin)
throws IOException {
Name name;
int ttl;
short type, dclass;
if (!useLast) name = new Name(st.nextToken(), origin);
else name = last.getName();
String s = st.nextToken();
try {
ttl = TTL.parseTTL(s);
s = st.nextToken();
} catch (NumberFormatException e) {
if (!useLast || last == null) ttl = defaultTTL;
else ttl = last.getTTL();
}
if ((dclass = DClass.value(s)) > 0) s = st.nextToken();
else dclass = DClass.IN;
if ((type = Type.value(s)) < 0) throw new IOException("Parse error");
return Record.fromString(name, type, dclass, ttl, st, origin);
}
/**
* Adds a record to the Zone
*
* @param r The record to be added
* @see Record
*/
public void addRecord(Record r) {
Name name = r.getName();
short type = r.getRRsetType();
RRset rrset = (RRset) findExactSet(name, type);
if (rrset == null) addSet(name, type, rrset = new RRset());
rrset.addRR(r);
}
/* Returns the number of records not successfully rendered. */
private int sectionToWire(DNSOutput out, int section, Compression c, int maxLength) {
int n = sections[section].size();
int pos = out.current();
int rendered = 0;
int skipped = 0;
Record lastrec = null;
for (int i = 0; i < n; i++) {
Record rec = (Record) sections[section].get(i);
if (section == Section.ADDITIONAL && rec instanceof OPTRecord) {
skipped++;
continue;
}
if (lastrec != null && !sameSet(rec, lastrec)) {
pos = out.current();
rendered = i;
}
lastrec = rec;
rec.toWire(out, section, c);
if (out.current() > maxLength) {
out.jump(pos);
return n - rendered + skipped;
}
}
return skipped;
}
/**
* Builds a new Record from its textual representation
*
* @param name The owner name of the record.
* @param type The record's type.
* @param dclass The record's class.
* @param ttl The record's time to live.
* @param st A tokenizer containing the textual representation of the rdata.
* @param origin The default origin to be appended to relative domain names.
* @return The new record
* @throws IOException The text format was invalid.
*/
public static Record fromString(
Name name, int type, int dclass, long ttl, Tokenizer st, Name origin) throws IOException {
Record rec;
if (!name.isAbsolute()) throw new RelativeNameException(name);
Type.check(type);
DClass.check(dclass);
TTL.check(ttl);
Tokenizer.Token t = st.get();
if (t.type == Tokenizer.IDENTIFIER && t.value.equals("\\#")) {
int length = st.getUInt16();
byte[] data = st.getHex();
if (data == null) {
data = new byte[0];
}
if (length != data.length)
throw st.exception("invalid unknown RR encoding: " + "length mismatch");
DNSInput in = new DNSInput(data);
return newRecord(name, type, dclass, ttl, length, in);
}
st.unget();
rec = getEmptyRecord(name, type, dclass, ttl, true);
rec.rdataFromString(st, origin);
t = st.get();
if (t.type != Tokenizer.EOL && t.type != Tokenizer.EOF) {
throw st.exception("unexpected tokens at end of record");
}
return rec;
}
/**
* Determines if two Records are identical. This compares the name, type, class, and rdata (with
* names canonicalized). The TTLs are not compared.
*
* @param arg The record to compare to
* @return true if the records are equal, false otherwise.
*/
public boolean equals(Object arg) {
if (arg == null || !(arg instanceof Record)) return false;
Record r = (Record) arg;
if (type != r.type || dclass != r.dclass || !name.equals(r.name)) return false;
byte[] array1 = rdataToWireCanonical();
byte[] array2 = r.rdataToWireCanonical();
return Arrays.equals(array1, array2);
}
/**
* 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);
}
/**
* Removes a record from the Zone
*
* @param r The record to be removed
* @see Record
*/
public void removeRecord(Record r) {
Name name = r.getName();
short type = r.getRRsetType();
RRset rrset = (RRset) findExactSet(name, type);
if (rrset != null) {
rrset.deleteRR(r);
if (rrset.size() == 0) removeSet(name, type, rrset);
}
}
/**
* Removes a record from the Zone
*
* @param r The record to be removed
* @see Record
*/
public void removeRecord(Record r) {
Name name = r.getName();
int rtype = r.getRRsetType();
synchronized (this) {
RRset rrset = findRRset(name, rtype);
if (rrset == null) return;
rrset.deleteRR(r);
if (rrset.size() == 0) removeRRset(name, rtype);
}
}
private static final Record getEmptyRecord(
Name name, int type, int dclass, long ttl, boolean hasData) {
Record rec;
if (hasData) rec = getTypedObject(type).getObject();
else rec = new EmptyRecord();
rec.name = name;
rec.type = type;
rec.dclass = dclass;
rec.ttl = ttl;
return rec;
}
void toWire(DNSOutput out) {
header.toWire(out);
Compression c = new Compression();
for (int i = 0; i < 4; i++) {
if (sections[i] == null) continue;
for (int j = 0; j < sections[i].size(); j++) {
Record rec = (Record) sections[i].get(j);
rec.toWire(out, i, c);
}
}
}
/**
* Adds a Record to the Zone
*
* @param r The record to be added
* @see Record
*/
public void addRecord(Record r) {
Name name = r.getName();
int rtype = r.getRRsetType();
synchronized (this) {
RRset rrset = findRRset(name, rtype);
if (rrset == null) {
rrset = new RRset(r);
addRRset(name, rrset);
} else {
rrset.addRR(r);
}
}
}
private static Record newRecord(
Name name, int type, int dclass, long ttl, int length, DNSInput in) throws IOException {
Record rec;
int recstart;
rec = getEmptyRecord(name, type, dclass, ttl, in != null);
if (in != null) {
if (in.remaining() < length) throw new WireParseException("truncated record");
in.setActive(length);
rec.rrFromWire(in);
if (in.remaining() > 0) throw new WireParseException("invalid record length");
in.clearActive();
}
return rec;
}
@Test
public void itLogsServerErrors() throws Exception {
header.setRcode(Rcode.REFUSED);
Name name = Name.fromString("John Wayne.");
Record question = Record.newRecord(name, 65530, 43210);
Message query = Message.newQuery(question);
Message response = mock(Message.class);
when(response.getHeader()).thenReturn(header);
when(response.getSectionArray(Section.ANSWER)).thenReturn(null);
when(response.getQuestion()).thenReturn(question);
when(nameServer.query(
any(Message.class), any(InetAddress.class), any(DNSAccessRecord.Builder.class)))
.thenThrow(new RuntimeException("Aw snap!"));
FakeAbstractProtocol abstractProtocol = new FakeAbstractProtocol(client, query.toWire());
abstractProtocol.setNameServer(nameServer);
abstractProtocol.run();
verify(accessLogger)
.info(
"144140678.000 qtype=DNS chi=192.168.23.45 ttms=345.123 xn=65535 fqdn=John\\032Wayne. type=TYPE65530 class=CLASS43210 rcode=SERVFAIL rtype=- rloc=\"-\" rdtl=- rerr=\"Server Error:RuntimeException:Aw snap!\" ttl=\"-\" ans=\"-\"");
}
/**
* Asynchronously sends a message to a single server, registering a listener to receive a callback
* on success or exception. Multiple asynchronous lookups can be performed in parallel. Since the
* callback may be invoked before the function returns, external synchronization is necessary.
*
* @param query The query to send
* @param listener The object containing the callbacks.
* @return An identifier, which is also a parameter in the callback
*/
public Object sendAsync(final Message query, final ResolverListener listener) {
final Object id;
synchronized (this) {
id = new Integer(uniqueID++);
}
Record question = query.getQuestion();
String qname;
if (question != null) qname = question.getName().toString();
else qname = "(none)";
String name = this.getClass() + ": " + qname;
Thread thread = new ResolveThread(this, query, id, listener);
thread.setName(name);
thread.setDaemon(true);
thread.start();
return id;
}
/**
* Constructs and returns the next record in the expansion.
*
* @throws IOException The name or rdata was invalid after substitutions were performed.
*/
public Record nextRecord() throws IOException {
if (current > end) return null;
String namestr = substitute(namePattern, current);
Name name = Name.fromString(namestr, origin);
String rdata = substitute(rdataPattern, current);
current += step;
return Record.fromString(name, type, dclass, ttl, rdata, origin);
}
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);
}
/**
* Adds a record to the Cache.
*
* @param r The record to be added
* @param cred The credibility of the record
* @param o The source of the record (this could be a Message, for example)
* @see Record
*/
public void addRecord(Record r, byte cred, Object o) {
Name name = r.getName();
short type = r.getRRsetType();
if (!Type.isRR(type)) return;
boolean addrrset = false;
Element element = (Element) findExactSet(name, type);
if (element == null || cred > element.credibility) {
RRset rrset = new RRset();
rrset.addRR(r);
addRRset(rrset, cred);
} else if (cred == element.credibility) {
if (element instanceof PositiveElement) {
PositiveElement pe = (PositiveElement) element;
pe.rrset.addRR(r);
}
}
}
/**
* 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();
}
/**
* Compares this Record to another Object.
*
* @param o The Object to be compared.
* @return The value 0 if the argument is a record equivalent to this record; a value less than 0
* if the argument is less than this record in the canonical ordering, and a value greater
* than 0 if the argument is greater than this record in the canonical ordering. The canonical
* ordering is defined to compare by name, class, type, and rdata.
* @throws ClassCastException if the argument is not a Record.
*/
public int compareTo(Object o) {
Record arg = (Record) o;
if (this == arg) return (0);
int n = name.compareTo(arg.name);
if (n != 0) return (n);
n = dclass - arg.dclass;
if (n != 0) return (n);
n = type - arg.type;
if (n != 0) return (n);
byte[] rdata1 = rdataToWireCanonical();
byte[] rdata2 = arg.rdataToWireCanonical();
for (int i = 0; i < rdata1.length && i < rdata2.length; i++) {
n = (rdata1[i] & 0xFF) - (rdata2[i] & 0xFF);
if (n != 0) return (n);
}
return (rdata1.length - rdata2.length);
}
/**
* Constructs and returns all records in the expansion.
*
* @throws IOException The name or rdata of a record was invalid after substitutions were
* performed.
*/
public Record[] expand() throws IOException {
List list = new ArrayList();
for (long i = start; i < end; i += step) {
String namestr = substitute(namePattern, current);
Name name = Name.fromString(namestr, origin);
String rdata = substitute(rdataPattern, current);
list.add(Record.fromString(name, type, dclass, ttl, rdata, origin));
}
return (Record[]) list.toArray(new Record[list.size()]);
}
private static final Record getTypedObject(int type) {
if (type < 0 || type > knownRecords.length) return unknownRecord.getObject();
if (knownRecords[type] != null) return knownRecords[type];
/* Construct the class name by putting the type before "Record". */
String s =
Record.class.getPackage().getName() + "." + Type.string(type).replace('-', '_') + "Record";
try {
Class c = Class.forName(s);
Constructor m = c.getDeclaredConstructor(emptyClassArray);
knownRecords[type] = (Record) m.newInstance(emptyObjectArray);
} catch (ClassNotFoundException e) {
/* This is normal; do nothing */
} catch (Exception e) {
if (Options.check("verbose")) System.err.println(e);
}
if (knownRecords[type] == null) knownRecords[type] = unknownRecord.getObject();
return knownRecords[type];
}
/**
* Creates an array containing fields of the SIG record and the RRsets to be signed/verified.
*
* @param sig The SIG record used to sign/verify the rrset.
* @param rrset The data to be signed/verified.
* @return The data to be cryptographically signed or verified.
*/
public static byte[] digestRRset(SIGRecord sig, RRset rrset) {
DataByteOutputStream out = new DataByteOutputStream();
digestSIG(out, sig);
int size = rrset.size();
byte[][] records = new byte[size][];
Iterator it = rrset.rrs();
Name name = rrset.getName();
Name wild = null;
if (name.labels() > sig.getLabels()) wild = name.wild(name.labels() - sig.getLabels());
while (it.hasNext()) {
Record rec = (Record) it.next();
if (wild != null) rec = rec.withName(wild);
records[--size] = rec.toWireCanonical();
}
Arrays.sort(records);
for (int i = 0; i < records.length; i++) out.writeArray(records[i]);
return out.toByteArray();
}
/* Returns the number of records not successfully rendered. */
private int sectionToWire(DNSOutput out, int section, Compression c, int maxLength) {
int n = sections[section].size();
int pos = out.current();
int rendered = 0;
Record lastrec = null;
for (int i = 0; i < n; i++) {
Record rec = (Record) sections[section].get(i);
if (lastrec != null && !sameSet(rec, lastrec)) {
pos = out.current();
rendered = i;
}
lastrec = rec;
rec.toWire(out, section, c);
if (out.current() > maxLength) {
out.jump(pos);
return n - rendered;
}
}
return 0;
}
@Test
public void itLogsARecordQueries() throws Exception {
header.setRcode(Rcode.NOERROR);
Name name = Name.fromString("www.example.com.");
Record question = Record.newRecord(name, Type.A, DClass.IN, 0L);
Message query = Message.newQuery(question);
query.getHeader().getRcode();
byte[] queryBytes = query.toWire();
whenNew(Message.class).withArguments(queryBytes).thenReturn(query);
InetAddress resolvedAddress = Inet4Address.getByName("192.168.8.9");
Record answer = new ARecord(name, DClass.IN, 3600L, resolvedAddress);
Record[] answers = new Record[] {answer};
Message response = mock(Message.class);
when(response.getHeader()).thenReturn(header);
when(response.getSectionArray(Section.ANSWER)).thenReturn(answers);
when(response.getQuestion()).thenReturn(question);
InetAddress client = Inet4Address.getByName("192.168.23.45");
when(nameServer.query(
any(Message.class), any(InetAddress.class), any(DNSAccessRecord.Builder.class)))
.thenReturn(response);
FakeAbstractProtocol abstractProtocol = new FakeAbstractProtocol(client, queryBytes);
abstractProtocol.setNameServer(nameServer);
abstractProtocol.run();
verify(accessLogger)
.info(
"144140678.000 qtype=DNS chi=192.168.23.45 ttms=345.123 xn=65535 fqdn=www.example.com. type=A class=IN rcode=NOERROR rtype=- rloc=\"-\" rdtl=- rerr=\"-\" ttl=\"3600\" ans=\"192.168.8.9\"");
}
/**
* Creates a Zone by performing a zone transfer to the specified host. All records that do not
* belong in the Zone are added to the specified Cache.
*
* @see Cache
* @see Master
*/
public Zone(Name zone, short dclass, String remote, Cache cache) throws IOException {
super(false);
origin = zone;
this.dclass = dclass;
type = SECONDARY;
Resolver res = new SimpleResolver(remote);
Record rec = Record.newRecord(zone, Type.AXFR, dclass);
Message query = Message.newQuery(rec);
Message response = res.send(query);
Record[] recs = response.getSectionArray(Section.ANSWER);
for (int i = 0; i < recs.length; i++) {
if (!recs[i].getName().subdomain(origin)) {
if (Options.check("verbose"))
System.err.println(recs[i].getName() + "is not in zone " + origin);
continue;
}
addRecord(recs[i]);
}
if (cache != null) {
recs = response.getSectionArray(Section.ADDITIONAL);
for (int i = 0; i < recs.length; i++) cache.addRecord(recs[i], Credibility.GLUE, recs);
}
validate();
}
/**
* Creates a new record identical to the current record, but with a different name. This is most
* useful for replacing the name of a wildcard record.
*/
public Record withName(Name name) {
if (!name.isAbsolute()) throw new RelativeNameException(name);
Record rec = cloneRecord();
rec.name = name;
return rec;
}
private static boolean sameSet(Record r1, Record r2) {
return (r1.getRRsetType() == r2.getRRsetType()
&& r1.getDClass() == r2.getDClass()
&& r1.getName().equals(r2.getName()));
}
/**
* Creates a new record identical to the current record, but with a different class and ttl. This
* is most useful for dynamic update.
*/
Record withDClass(int dclass, long ttl) {
Record rec = cloneRecord();
rec.dclass = dclass;
rec.ttl = ttl;
return rec;
}
