/* 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;
}
void toWire(DNSOutput out, int section, Compression c) {
name.toWire(out, c);
out.writeU16(type);
out.writeU16(dclass);
if (section == Section.QUESTION) return;
out.writeU32(ttl);
int lengthPosition = out.current();
out.writeU16(0); /* until we know better */
rrToWire(out, c, false);
int rrlength = out.current() - lengthPosition - 2;
out.save();
out.jump(lengthPosition);
out.writeU16(rrlength);
out.restore();
}
private void toWireCanonical(DNSOutput out, boolean noTTL) {
name.toWireCanonical(out);
out.writeU16(type);
out.writeU16(dclass);
if (noTTL) {
out.writeU32(0);
} else {
out.writeU32(ttl);
}
int lengthPosition = out.current();
out.writeU16(0); /* until we know better */
rrToWire(out, null, true);
int rrlength = out.current() - lengthPosition - 2;
out.save();
out.jump(lengthPosition);
out.writeU16(rrlength);
out.restore();
}
/* 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;
}
/* Returns true if the message could be rendered. */
private boolean toWire(DNSOutput out, int maxLength) {
if (maxLength < Header.LENGTH) return false;
Header newheader = null;
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);
out.writeU16At(additionalCount + 1, startpos + 10);
}
return true;
}
/* Returns true if the message could be rendered. */
private boolean toWire(DNSOutput out, int maxLength) {
if (maxLength < Header.LENGTH) return false;
Header newheader = null;
int tempMaxLength = maxLength;
if (tsigkey != null) tempMaxLength -= tsigkey.recordLength();
int startpos = out.current();
header.toWire(out);
Compression c = new Compression();
for (int i = 0; i < 4; i++) {
int skipped;
if (sections[i] == null) continue;
skipped = sectionToWire(out, i, c, tempMaxLength);
if (skipped != 0) {
if (i != Section.ADDITIONAL) {
if (newheader == null) newheader = (Header) header.clone();
newheader.setFlag(Flags.TC);
int count = newheader.getCount(i);
newheader.setCount(i, count - skipped);
for (int j = i + 1; j < 4; j++) newheader.setCount(j, 0);
out.save();
out.jump(startpos);
newheader.toWire(out);
out.restore();
}
break;
}
}
if (tsigkey != null) {
TSIGRecord tsigrec = tsigkey.generate(this, out.toByteArray(), tsigerror, querytsig);
if (newheader == null) newheader = (Header) header.clone();
tsigrec.toWire(out, Section.ADDITIONAL, c);
newheader.incCount(Section.ADDITIONAL);
out.save();
out.jump(startpos);
newheader.toWire(out);
out.restore();
}
return true;
}
/**
* Returns an array containing the wire format representation of the Message with the specified
* maximum length. This will generate a truncated message (with the TC bit) if the message doesn't
* fit, and will also sign the message with the TSIG key set by a call to setTSIG(). This method
* may return null if the message could not be rendered at all; this could happen if maxLength is
* smaller than a DNS header, for example.
*
* @param maxLength The maximum length of the message.
* @return The wire format of the message, or null 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. */
public byte[] toWire() {
DNSOutput out = new DNSOutput();
toWire(out);
size = out.current();
return out.toByteArray();
}
