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Copy pathMessage.java
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1144 lines (1034 loc) · 33.8 KB
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// SPDX-License-Identifier: BSD-3-Clause
// Copyright (c) 1999-2004 Brian Wellington (bwelling@xbill.org)
// Copyright (c) 2007-2023 NLnet Labs
package org.xbill.DNS;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Optional;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
/**
* A DNS Message. A message is the basic unit of communication between the client and server of a
* DNS operation. A message consists of a Header and 4 message sections.
*
* @see Resolver
* @see Header
* @see Section
* @author Brian Wellington
*/
@Slf4j
public class Message implements Cloneable {
/** The maximum length of a message in wire format. */
public static final int MAXLENGTH = 65535;
private Header header;
private List<Record>[] sections;
private int size;
private TSIG tsigkey;
private TSIGRecord generatedTsig;
private TSIGRecord querytsig;
private int tsigerror;
private Resolver resolver;
int tsigstart;
int tsigState;
int sig0start;
/** The message was not signed */
static final int TSIG_UNSIGNED = 0;
/** The message was signed and verification succeeded */
static final int TSIG_VERIFIED = 1;
/** The message was an unsigned message in multiple-message response */
static final int TSIG_INTERMEDIATE = 2;
/** The message was signed and no verification was attempted. */
static final int TSIG_SIGNED = 3;
/** The message was signed and verification failed, or was not signed when it should have been. */
static final int TSIG_FAILED = 4;
private static final Record[] emptyRecordArray = new Record[0];
@SuppressWarnings({"unchecked"})
private Message(Header header) {
sections = (List<Record>[]) new List<?>[4];
this.header = header;
}
/** Creates a new Message with the specified Message ID */
public Message(int id) {
this(new Header(id));
}
/** Creates a new Message with a random Message ID */
public Message() {
this(new Header());
}
/**
* Creates a new Message with a random Message ID suitable for sending as a query.
*
* @param r A record containing the question
*/
public static Message newQuery(Record r) {
Message m = new Message();
m.header.setOpcode(Opcode.QUERY);
m.header.setFlag(Flags.RD);
m.addRecord(r, Section.QUESTION);
return m;
}
/**
* Creates a new Message to contain a dynamic update. A random Message ID and the zone are filled
* in.
*
* @param zone The zone to be updated
*/
public static Message newUpdate(Name zone) {
return new Update(zone);
}
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 (j != count - 1) {
throw new WireParseException("TSIG is not the last record in the message");
}
}
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();
}
/**
* Creates a new Message from its DNS wire format representation
*
* @param b A byte array containing the DNS Message.
*/
public Message(byte[] b) throws IOException {
this(new DNSInput(b));
}
/**
* Creates a new Message from its DNS wire format representation
*
* @param byteBuffer A ByteBuffer containing the DNS Message.
*/
public Message(ByteBuffer byteBuffer) throws IOException {
this(new DNSInput(byteBuffer));
}
/**
* Replaces the Header with a new one.
*
* @see Header
*/
public void setHeader(Header h) {
header = h;
}
/**
* Retrieves the Header.
*
* @see Header
*/
public Header getHeader() {
return header;
}
/**
* Adds a record to a section of the Message, and adjusts the header.
*
* @see Record
* @see Section
*/
public void addRecord(Record r, int section) {
if (sections[section] == null) {
sections[section] = new LinkedList<>();
}
header.incCount(section);
sections[section].add(r);
}
/**
* Removes a record from a section of the Message, and adjusts the header.
*
* @see Record
* @see Section
*/
public boolean removeRecord(Record r, int section) {
Section.check(section);
if (sections[section] != null && sections[section].remove(r)) {
header.decCount(section);
return true;
} else {
return false;
}
}
/**
* Removes all records from a section of the Message, and adjusts the header.
*
* @see Record
* @see Section
*/
public void removeAllRecords(int section) {
Section.check(section);
sections[section] = null;
header.setCount(section, 0);
}
/**
* Determines if the given record is already present in the given section.
*
* @see Record
* @see Section
*/
public boolean findRecord(Record r, int section) {
Section.check(section);
return sections[section] != null && sections[section].contains(r);
}
/**
* Determines if the given record is already present in any section.
*
* @see Record
* @see Section
*/
public boolean findRecord(Record r) {
for (int i = Section.ANSWER; i <= Section.ADDITIONAL; i++) {
if (sections[i] != null && sections[i].contains(r)) {
return true;
}
}
return false;
}
/**
* 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) {
Type.check(type);
Section.check(section);
if (sections[section] == null) {
return false;
}
for (int i = 0; i < sections[section].size(); i++) {
Record r = sections[section].get(i);
if (r.getType() == type && name.equals(r.getName())) {
return true;
}
}
return false;
}
/**
* Determines if an RRset with the given name and type is already present in any section.
*
* @see RRset
* @see Section
*/
public boolean findRRset(Name name, int type) {
return findRRset(name, type, Section.ANSWER)
|| findRRset(name, type, Section.AUTHORITY)
|| findRRset(name, type, Section.ADDITIONAL);
}
/**
* Returns the first record in the QUESTION section.
*
* @see Record
* @see Section
*/
public Record getQuestion() {
List<Record> l = sections[Section.QUESTION];
if (l == null || l.isEmpty()) {
return null;
}
return l.get(0);
}
/**
* Returns the TSIG record from the ADDITIONAL section, if one is present.
*
* @see TSIGRecord
* @see TSIG
* @see Section
*/
public TSIGRecord getTSIG() {
int count = header.getCount(Section.ADDITIONAL);
if (count == 0) {
return null;
}
List<Record> l = sections[Section.ADDITIONAL];
Record rec = l.get(count - 1);
if (rec.type != Type.TSIG) {
return null;
}
return (TSIGRecord) rec;
}
/**
* Gets the generated {@link TSIGRecord}. Only valid if the messages has been converted to wire
* format with {@link #toWire(int)} before.
*
* @return A generated TSIG record or {@code null}.
*/
TSIGRecord getGeneratedTSIG() {
return generatedTsig;
}
/**
* Was this message signed by a TSIG?
*
* @see TSIG
*/
public boolean isSigned() {
return tsigState == TSIG_SIGNED || tsigState == TSIG_VERIFIED || tsigState == TSIG_FAILED;
}
/**
* If this message was signed by a TSIG, was the TSIG verified?
*
* @see TSIG
*/
public boolean isVerified() {
return tsigState == TSIG_VERIFIED;
}
/**
* Returns the OPT record from the ADDITIONAL section, if one is present.
*
* @see OPTRecord
* @see Section
*/
public OPTRecord getOPT() {
for (Record r : getSection(Section.ADDITIONAL)) {
if (r instanceof OPTRecord) {
return (OPTRecord) r;
}
}
return null;
}
/** Returns the message's rcode (error code). This incorporates the EDNS extended rcode. */
public int getRcode() {
int rcode = header.getRcode();
OPTRecord opt = getOPT();
if (opt != null) {
rcode += opt.getExtendedRcode() << 4;
}
return rcode;
}
/**
* Returns an array containing all records in the given section, or an empty array if the section
* is empty.
*
* @see Record
* @see Section
* @deprecated use {@link #getSection(int)}
*/
@Deprecated
public Record[] getSectionArray(int section) {
Section.check(section);
if (sections[section] == null) {
return emptyRecordArray;
}
List<Record> l = sections[section];
return l.toArray(new Record[0]);
}
/**
* Returns all records in the given section, or an empty list if the section is empty.
*
* @see Record
* @see Section
*/
public List<Record> getSection(int section) {
Section.check(section);
if (sections[section] == null) {
return Collections.emptyList();
}
return Collections.unmodifiableList(sections[section]);
}
/**
* Returns an array containing all records in the given section grouped into RRsets.
*
* @see RRset
* @see Section
*/
@SuppressWarnings("java:S1119") // label
public List<RRset> getSectionRRsets(int section) {
Section.check(section);
if (sections[section] == null) {
return Collections.emptyList();
}
List<RRset> sets = new LinkedList<>();
record_iteration:
for (Record rec : sections[section]) {
for (int j = sets.size() - 1; j >= 0; j--) {
RRset set = sets.get(j);
if (rec.sameRRset(set)) {
set.addRR(rec);
// Existing set found, continue with the next record
continue record_iteration;
}
}
// No existing set found, create a new one
sets.add(new RRset(rec));
}
return sets;
}
void toWire(DNSOutput out) {
header.toWire(out);
Compression c = new Compression();
for (int i = 0; i < sections.length; i++) {
if (sections[i] == null) {
continue;
}
for (Record rec : sections[i]) {
rec.toWire(out, i, c);
}
}
}
/* 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 count = 0;
Record lastrec = null;
for (int i = 0; i < n; i++) {
Record rec = sections[section].get(i);
if (section == Section.ADDITIONAL && rec instanceof OPTRecord) {
continue;
}
if (lastrec != null && !rec.sameRRset(lastrec)) {
pos = out.current();
rendered = count;
}
lastrec = rec;
rec.toWire(out, section, c);
if (out.current() > maxLength) {
out.jump(pos);
return n - rendered;
}
count++;
}
return n - count;
}
/* Returns true if the message could be completely rendered (i.e. not truncated). */
private boolean toWire(DNSOutput out, int maxLength) {
if (maxLength < Header.LENGTH) {
return false;
}
int tempMaxLength = maxLength;
if (tsigkey != null) {
tempMaxLength -= tsigkey.recordLength();
}
OPTRecord opt = getOPT();
byte[] optBytes = null;
if (opt != null) {
optBytes = opt.toWire(Section.ADDITIONAL);
tempMaxLength -= optBytes.length;
}
int startpos = out.current();
header.toWire(out);
Compression c = new Compression();
int flags = header.getFlagsByte();
int additionalCount = 0;
for (int i = 0; i < 4; i++) {
int skipped;
if (sections[i] == null) {
continue;
}
skipped = sectionToWire(out, i, c, tempMaxLength);
if (skipped != 0 && i != Section.ADDITIONAL) {
flags = Header.setFlag(flags, Flags.TC, true);
out.writeU16At(header.getCount(i) - skipped, startpos + 4 + 2 * i);
for (int j = i + 1; j < Section.ADDITIONAL; j++) {
out.writeU16At(0, startpos + 4 + 2 * j);
}
break;
}
if (i == Section.ADDITIONAL) {
additionalCount = header.getCount(i) - skipped;
}
}
if (optBytes != null) {
out.writeByteArray(optBytes);
additionalCount++;
}
if (flags != header.getFlagsByte()) {
out.writeU16At(flags, startpos + 2);
}
if (additionalCount != header.getCount(Section.ADDITIONAL)) {
out.writeU16At(additionalCount, startpos + 10);
}
if (tsigkey != null) {
TSIGRecord tsigrec = tsigkey.generate(this, out.toByteArray(), tsigerror, querytsig);
tsigrec.toWire(out, Section.ADDITIONAL, c);
generatedTsig = tsigrec;
out.writeU16At(additionalCount + 1, startpos + 10);
}
return !Header.getFlag(flags, Flags.TC);
}
/**
* Returns an array containing the wire format representation of the {@link Message}, but does not
* do any additional processing (e.g. OPT/TSIG records, truncation).
*
* <p>Do NOT use this to actually transmit a message, use {@link #toWire(int)} instead.
*/
public byte[] toWire() {
DNSOutput out = new DNSOutput();
toWire(out);
size = out.current();
return out.toByteArray();
}
/**
* Returns an array containing the wire format representation of the Message with the specified
* maximum length. Equivalent to calling {@link #toWire(int maxLength, boolean truncate)
* toWire(maxLength, true)}.
*
* <p>Do NOT use this method in conjunction with {@link TSIG#apply(Message, TSIGRecord)}, it
* produces inconsistent results! Use {@link #setTSIG(TSIG, int, TSIGRecord)} instead.
*
* @param maxLength The maximum length of the message.
* @return The wire format of the message, or an empty array if the message could not be rendered
* into the specified length.
* @see Flags
* @see TSIG
*/
public byte[] toWire(int maxLength) {
DNSOutput out = new DNSOutput();
toWire(out, maxLength);
size = out.current();
return out.toByteArray();
}
/**
* Returns an array containing the wire format representation of the Message with the specified
* maximum length. If {@code truncate} is {@code true} it will generate a truncated message (with
* the TC bit) if the message doesn't fit, otherwise an exception will be thrown. It will also
* sign the message with the TSIG key set by a call to {@link #setTSIG(TSIG, int, TSIGRecord)}.
* This method may return an empty byte array if the message could not be rendered at all; this
* could happen if maxLength is smaller than a DNS header, for example.
*
* <p>Do NOT use this method in conjunction with {@link TSIG#apply(Message, TSIGRecord)}, it
* produces inconsistent results! Use {@link #setTSIG(TSIG, int, TSIGRecord)} instead.
*
* @param maxLength The maximum length of the message.
* @return The wire format of the message, or an empty array if the message could not be rendered
* into the specified length.
* @throws MessageSizeExceededException When the message size would exceed the specified {@code
* maxLength}.
* @see Flags
* @see TSIG
*/
public byte[] toWire(int maxLength, boolean truncate) throws MessageSizeExceededException {
DNSOutput out = new DNSOutput();
boolean completelyRendered = toWire(out, maxLength);
if (!completelyRendered && !truncate) {
throw new MessageSizeExceededException(maxLength);
}
size = out.current();
return out.toByteArray();
}
/**
* Sets the TSIG key to sign a message.
*
* @param key The TSIG key.
* @since 3.5.1
*/
public void setTSIG(TSIG key) {
setTSIG(key, Rcode.NOERROR, null);
}
/**
* Sets the TSIG key and other necessary information to sign a message.
*
* @param key The TSIG key.
* @param error The value of the TSIG error field.
* @param querytsig If this is a response, the TSIG from the request.
*/
public void setTSIG(TSIG key, int error, TSIGRecord querytsig) {
this.tsigkey = key;
this.tsigerror = error;
this.querytsig = querytsig;
}
/**
* Returns the size of the message. Only valid if the message has been converted to or from wire
* format.
*/
public int numBytes() {
return size;
}
/**
* Converts the given section of the Message to a String.
*
* @see Section
*/
public String sectionToString(int section) {
Section.check(section);
StringBuilder sb = new StringBuilder();
sectionToString(sb, section);
return sb.toString();
}
private void sectionToString(StringBuilder sb, int i) {
if (i > 3) {
return;
}
for (Record rec : getSection(i)) {
if (i == Section.QUESTION) {
sb.append(";;\t").append(rec.name);
sb.append(", type = ").append(Type.string(rec.type));
sb.append(", class = ").append(DClass.string(rec.dclass));
} else {
if (!(rec instanceof OPTRecord)) {
sb.append(rec);
}
}
sb.append("\n");
}
}
/** Converts the Message to a String. */
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
OPTRecord opt = getOPT();
if (opt != null) {
sb.append(header.toStringWithRcode(getRcode())).append("\n\n");
opt.printPseudoSection(sb);
sb.append('\n');
} else {
sb.append(header).append('\n');
}
if (isSigned()) {
sb.append(";; TSIG ");
if (isVerified()) {
sb.append("ok");
} else {
sb.append("invalid");
}
sb.append('\n');
}
for (int i = 0; i < 4; i++) {
if (header.getOpcode() != Opcode.UPDATE) {
sb.append(";; ").append(Section.longString(i)).append(":\n");
} else {
sb.append(";; ").append(Section.updString(i)).append(":\n");
}
sectionToString(sb, i);
sb.append("\n");
}
sb.append(";; Message size: ").append(numBytes()).append(" bytes");
return sb.toString();
}
/**
* Creates a copy of this Message. This is done by the Resolver before adding TSIG and OPT
* records, for example.
*
* @see Resolver
* @see TSIGRecord
* @see OPTRecord
*/
@Override
@SneakyThrows(CloneNotSupportedException.class)
@SuppressWarnings({"unchecked", "java:S2975"})
public Message clone() {
Message m = (Message) super.clone();
m.sections = (List<Record>[]) new List<?>[sections.length];
for (int i = 0; i < sections.length; i++) {
if (sections[i] != null) {
m.sections[i] = new LinkedList<>(sections[i]);
}
}
m.header = header.clone();
if (querytsig != null) {
m.querytsig = (TSIGRecord) querytsig.cloneRecord();
}
if (generatedTsig != null) {
m.generatedTsig = (TSIGRecord) generatedTsig.cloneRecord();
}
return m;
}
/** Sets the resolver that originally received this Message from a server. */
public void setResolver(Resolver resolver) {
this.resolver = resolver;
}
/** Gets the resolver that originally received this Message from a server. */
public Optional<Resolver> getResolver() {
return Optional.ofNullable(resolver);
}
/**
* Checks if a record {@link Type} is allowed within a {@link Section}.
*
* @return {@code true} if the type is allowed, {@code false} otherwise.
*/
boolean isTypeAllowedInSection(int type, int section) {
Type.check(type);
Section.check(section);
switch (section) {
case Section.AUTHORITY:
if (type == Type.SOA
|| type == Type.NS
|| type == Type.DS
|| type == Type.NSEC
|| type == Type.NSEC3) {
return true;
}
break;
case Section.ADDITIONAL:
if (type == Type.A || type == Type.AAAA) {
return true;
}
break;
}
return !Boolean.parseBoolean(System.getProperty("dnsjava.harden_unknown_additional", "true"));
}
/**
* Creates a normalized copy of this message by following xNAME chains, synthesizing CNAMEs from
* DNAMEs if necessary, and removing illegal RRsets from {@link Section#AUTHORITY} and {@link
* Section#ADDITIONAL}.
*
* <p>Normalization is only applied to {@link Rcode#NOERROR} and {@link Rcode#NXDOMAIN} responses.
*
* <p>This method is equivalent to calling {@link #normalize(Message, boolean)} with {@code
* false}.
*
* @param query The query that produced this message.
* @return {@code null} if the message could not be normalized or is otherwise invalid.
* @since 3.6
*/
public Message normalize(Message query) {
try {
return normalize(query, false);
} catch (WireParseException e) {
// Cannot happen with 'false'
}
return null;
}
/**
* Creates a normalized copy of this message by following xNAME chains, synthesizing CNAMEs from
* DNAMEs if necessary, and removing illegal RRsets from {@link Section#AUTHORITY} and {@link
* Section#ADDITIONAL}.
*
* <p>Normalization is only applied to {@link Rcode#NOERROR} and {@link Rcode#NXDOMAIN} responses.
*
* @param query The query that produced this message.
* @param throwOnIrrelevantRecord If {@code true}, throw an exception instead of silently ignoring
* irrelevant records.
* @return {@code null} if the message could not be normalized or is otherwise invalid.
* @throws WireParseException when {@code throwOnIrrelevantRecord} is {@code true} and an invalid
* or irrelevant record was found.
* @since 3.6
*/
public Message normalize(Message query, boolean throwOnIrrelevantRecord)
throws WireParseException {
if (getRcode() != Rcode.NOERROR && getRcode() != Rcode.NXDOMAIN) {
return this;
}
Name sname = query.getQuestion().getName();
List<RRset> answerSectionSets = getSectionRRsets(Section.ANSWER);
List<RRset> additionalSectionSets = getSectionRRsets(Section.ADDITIONAL);
List<RRset> authoritySectionSets = getSectionRRsets(Section.AUTHORITY);
@SuppressWarnings({"unchecked", "rawtypes"})
List<RRset>[] cleanedSection = new ArrayList[4];
cleanedSection[Section.ANSWER] = new ArrayList<>();
cleanedSection[Section.AUTHORITY] = new ArrayList<>();
cleanedSection[Section.ADDITIONAL] = new ArrayList<>();
boolean hadNsInAuthority = false;
// For the ANSWER section, remove all "irrelevant" records and add synthesized CNAMEs from
// DNAMEs. This will strip out-of-order CNAMEs as well.
for (int i = 0; i < answerSectionSets.size(); i++) {
RRset rrset = answerSectionSets.get(i);
Name oldSname = sname;
if (rrset.getType() == Type.DNAME && sname.subdomain(rrset.getName())) {
if (rrset.size() > 1) {
String template =
"Normalization failed in response to <{}/{}/{}> (id {}), found {} entries (instead of just one) in DNAME RRSet <{}/{}>";
if (throwOnIrrelevantRecord) {
throw new WireParseException(template.replace("{}", "%s"));
}
log.warn(
template,
sname,
Type.string(query.getQuestion().getType()),
DClass.string(query.getQuestion().getDClass()),
getHeader().getID(),
rrset.size(),
rrset.getName(),
DClass.string(rrset.getDClass()));
return null;
}
// If DNAME was queried, don't attempt to synthesize CNAME
if (query.getQuestion().getType() != Type.DNAME) {
// The DNAME is valid, accept it
cleanedSection[Section.ANSWER].add(rrset);
// Check if the next rrset is correct CNAME, otherwise synthesize a CNAME
RRset nextRRSet = answerSectionSets.size() >= i + 2 ? answerSectionSets.get(i + 1) : null;
DNAMERecord dname = ((DNAMERecord) rrset.first());
try {
// Validate that an existing CNAME matches what we would synthesize
if (nextRRSet != null
&& nextRRSet.getType() == Type.CNAME
&& nextRRSet.getName().equals(sname)) {
Name expected =
Name.concatenate(
nextRRSet.getName().relativize(dname.getName()), dname.getTarget());
if (expected.equals(((CNAMERecord) nextRRSet.first()).getTarget())) {
continue;
}
}
// Add a synthesized CNAME; TTL=0 to avoid caching
Name dnameTarget = sname.fromDNAME(dname);
cleanedSection[Section.ANSWER].add(
new RRset(new CNAMERecord(sname, dname.getDClass(), 0, dnameTarget)));
sname = dnameTarget;
// In DNAME ANY response, can have data after DNAME
if (query.getQuestion().getType() == Type.ANY) {
for (i++; i < answerSectionSets.size(); i++) {
rrset = answerSectionSets.get(i);
if (rrset.getName().equals(oldSname)) {
cleanedSection[Section.ANSWER].add(rrset);
} else {
break;
}
}
}
continue;
} catch (NameTooLongException e) {
String template =
"Normalization failed in response to <{}/{}/{}> (id {}), could not synthesize CNAME for DNAME <{}/{}>";
if (throwOnIrrelevantRecord) {
throw new WireParseException(template.replace("{}", "%s"), e);
}
log.warn(
template,
sname,
Type.string(query.getQuestion().getType()),
DClass.string(query.getQuestion().getDClass()),
getHeader().getID(),
rrset.getName(),
DClass.string(rrset.getDClass()));
return null;
}
}
}
// Ignore irrelevant records
if (!sname.equals(rrset.getName())) {
logOrThrow(
throwOnIrrelevantRecord,
"Ignoring irrelevant RRset <{}/{}/{}> in response to <{}/{}/{}> (id {})",
rrset,
sname,
query);
continue;
}
// Follow CNAMEs
if (rrset.getType() == Type.CNAME && query.getQuestion().getType() != Type.CNAME) {
if (rrset.size() > 1) {
String template =
"Found {} CNAMEs in <{}/{}> response to <{}/{}/{}> (id {}), removing all but the first";
if (throwOnIrrelevantRecord) {
throw new WireParseException(
String.format(
template.replace("{}", "%s"),
rrset.rrs(false).size(),
rrset.getName(),
DClass.string(rrset.getDClass()),
sname,
Type.string(query.getQuestion().getType()),
DClass.string(query.getQuestion().getDClass()),
getHeader().getID()));
}
log.warn(
template,
rrset.rrs(false).size(),
rrset.getName(),
DClass.string(rrset.getDClass()),
sname,
Type.string(query.getQuestion().getType()),
DClass.string(query.getQuestion().getDClass()),
getHeader().getID());
List<Record> cnameRRset = rrset.rrs(false);
for (int cnameIndex = 1; cnameIndex < cnameRRset.size(); cnameIndex++) {
rrset.deleteRR(cnameRRset.get(i));
}
}
sname = ((CNAMERecord) rrset.first()).getTarget();
cleanedSection[Section.ANSWER].add(rrset);
// In CNAME ANY response, can have data after CNAME
if (query.getQuestion().getType() == Type.ANY) {
for (i++; i < answerSectionSets.size(); i++) {
rrset = answerSectionSets.get(i);
if (rrset.getName().equals(oldSname)) {
cleanedSection[Section.ANSWER].add(rrset);
} else {
break;
}
}
}
continue;
}
// Remove records that don't match the queried type
int qtype = getQuestion().getType();
if (qtype != Type.ANY && rrset.getActualType() != qtype) {
logOrThrow(
throwOnIrrelevantRecord,
"Ignoring irrelevant RRset <{}/{}/{}> in ANSWER section response to <{}/{}/{}> (id {})",
rrset,
sname,
query);
continue;
}
// Mark the additional names from relevant RRset as OK
cleanedSection[Section.ANSWER].add(rrset);
if (sname.equals(rrset.getName())) {
addAdditionalRRset(rrset, additionalSectionSets, cleanedSection[Section.ADDITIONAL]);
}
}
for (RRset rrset : authoritySectionSets) {
switch (rrset.getType()) {
case Type.DNAME:
case Type.CNAME:
case Type.A:
case Type.AAAA:
logOrThrow(
throwOnIrrelevantRecord,
"Ignoring forbidden RRset <{}/{}/{}> in AUTHORITY section response to <{}/{}/{}> (id {})",
rrset,
sname,
query);
continue;
}
if (!isTypeAllowedInSection(rrset.getType(), Section.AUTHORITY)) {
logOrThrow(