/**
* Copies the content of the most recently received packet into <tt>data</tt>.
*
* @param buffer an optional <tt>Buffer</tt> instance associated with the specified <tt>data</tt>,
* <tt>offset</tt> and <tt>length</tt> and provided to the method in case the implementation
* would like to provide additional <tt>Buffer</tt> properties such as <tt>flags</tt>
* @param data the <tt>byte[]</tt> that we'd like to copy the content of the packet to.
* @param offset the position where we are supposed to start writing in <tt>data</tt>.
* @param length the number of <tt>byte</tt>s available for writing in <tt>data</tt>.
* @return the number of bytes read
* @throws IOException if <tt>length</tt> is less than the size of the packet.
*/
protected int read(Buffer buffer, byte[] data, int offset, int length) throws IOException {
if (data == null) throw new NullPointerException("data");
if (ioError) return -1;
RawPacket pkt;
synchronized (pktSyncRoot) {
pkt = this.pkt;
this.pkt = null;
}
int pktLength;
if (pkt == null) {
pktLength = 0;
} else {
// By default, pkt will be returned to the pool after it was read.
boolean poolPkt = true;
try {
pktLength = pkt.getLength();
if (length < pktLength) {
/*
* If pkt is still the latest RawPacket made available to
* reading, reinstate it for the next invocation of read;
* otherwise, return it to the pool.
*/
poolPkt = false;
throw new IOException("Input buffer not big enough for " + pktLength);
} else {
byte[] pktBuffer = pkt.getBuffer();
if (pktBuffer == null) {
throw new NullPointerException(
"pkt.buffer null, pkt.length " + pktLength + ", pkt.offset " + pkt.getOffset());
} else {
System.arraycopy(pkt.getBuffer(), pkt.getOffset(), data, offset, pktLength);
if (buffer != null) buffer.setFlags(pkt.getFlags());
}
}
} finally {
if (!poolPkt) {
synchronized (pktSyncRoot) {
if (this.pkt == null) this.pkt = pkt;
else poolPkt = true;
}
}
if (poolPkt) {
// Return pkt to the pool because it was successfully read.
poolRawPacket(pkt);
}
}
}
return pktLength;
}
/**
* Return a set of all items with type CNAME from the RTCP SDES packet <tt>pkt</tt>.
*
* @param pkt the packet to parse for CNAME items.
* @retur a set of all items with type CNAME from the RTCP SDES packet <tt>pkt</tt>.
*/
private Set<CNAMEItem> getCnameItems(RawPacket pkt) {
Set<CNAMEItem> ret = new HashSet<CNAMEItem>();
byte[] buf = pkt.getBuffer();
int off = pkt.getOffset();
int len = pkt.getLength();
// first item
int ptr = 4;
while (ptr + 6 < len) // an item is at least 6B: 4B ssrc, 1B type, 1B len
{
int type = buf[off + ptr + 4];
int len2 = buf[off + ptr + 5];
if (ptr + 6 + len2 >= len) // not enough buffer for the whole item
break;
if (type == 1) // CNAME
{
CNAMEItem item = new CNAMEItem();
item.ssrc = readUnsignedIntAsLong(buf, off + ptr);
item.cname = readString(buf, off + ptr + 6, len2);
ret.add(item);
}
ptr += 6 + len2;
}
return ret;
}
/** {@inheritDoc} */
@Override
public RawPacket transform(RawPacket pkt) {
if (pkt == null) {
return pkt;
}
RTCPCompoundPacket inPacket;
try {
inPacket =
(RTCPCompoundPacket)
parser.parse(pkt.getBuffer(), pkt.getOffset(), pkt.getLength());
} catch (BadFormatException e) {
logger.warn("Failed to terminate an RTCP packet. " + "Dropping packet.");
return null;
}
// Update our RTCP stats map (timestamps). This operation is
// read-only.
remoteClockEstimator.apply(inPacket);
cnameRegistry.update(inPacket);
// Remove SRs and RRs from the RTCP packet.
pkt = feedbackGateway.gateway(inPacket);
return pkt;
}
private void emptyPacketBuffer(long ssrc) {
RawPacket[] pkts = rtpConnector.packetBuffer.emptyBuffer(ssrc);
RTPConnectorImpl.OutputDataStreamImpl dataStream;
try {
dataStream = rtpConnector.getDataOutputStream();
} catch (IOException ioe) {
logger.error("Failed to empty packet buffer for SSRC=" + ssrc + ": " + ioe);
return;
}
for (RawPacket pkt : pkts)
dataStream.write(
pkt.getBuffer(), pkt.getOffset(), pkt.getLength(), false /* already transformed */);
}
/**
* Creates a {@code RawPacket} which represents the original packet encapsulated in {@code pkt}
* using the RTX format.
*
* @param pkt the packet from which to extract a media packet.
* @return the extracted media packet.
*/
private RawPacket createMediaPacket(RawPacket pkt) {
RawPacket mediaPacket = null;
long rtxSsrc = pkt.getSSRC() & 0xffffffffL;
// We need to know the SSRC paired with rtxSsrc *as seen by the
// receiver (i.e. this.channel)*. However, we only store SSRCs
// that endpoints *send* with.
// We therefore assume that SSRC re-writing has not introduced any
// new SSRCs and therefor the FID mappings known to the senders
// also apply to receivers.
RtpChannel sourceChannel = channel.getContent().findChannelByFidSsrc(rtxSsrc);
if (sourceChannel != null) {
long mediaSsrc = sourceChannel.getFidPairedSsrc(rtxSsrc);
if (mediaSsrc != -1) {
byte apt = sourceChannel.getRtxAssociatedPayloadType();
if (apt != -1) {
mediaPacket = new RawPacket(pkt.getBuffer().clone(), pkt.getOffset(), pkt.getLength());
// Remove the RTX header by moving the RTP header two bytes
// right.
byte[] buf = mediaPacket.getBuffer();
int off = mediaPacket.getOffset();
System.arraycopy(buf, off, buf, off + 2, mediaPacket.getHeaderLength());
mediaPacket.setOffset(off + 2);
mediaPacket.setLength(pkt.getLength() - 2);
mediaPacket.setSSRC((int) mediaSsrc);
mediaPacket.setSequenceNumber(pkt.getOriginalSequenceNumber());
mediaPacket.setPayloadType(apt);
}
}
}
return mediaPacket;
}
/**
* Checks whether <tt>pkt</tt> looks like a valid RTCP packet.
*
* @param pkt the packet to check.
* @return <tt>true</tt> if <tt>pkt</tt> seems to be a valid RTCP packet.
*/
private boolean isValidRTCP(RawPacket pkt) {
byte[] buf = pkt.getBuffer();
int off = pkt.getOffset();
int len = pkt.getLength();
if (len < 4) return false;
int v = (buf[off] & 0xc0) >>> 6;
if (v != 2) return false;
int lengthInWords = (buf[off + 2] & 0xFF) << 8 | (buf[off + 3] & 0xFF);
int lengthInBytes = (lengthInWords + 1) * 4;
if (len < lengthInBytes) return false;
return true;
}
@Override
public int read(byte[] buffer, int offset, int length) throws IOException {
RawPacket pendingPacket;
if (isControlStream) {
pendingPacket = pendingControlPacket;
} else {
pendingPacket = pendingDataPacket;
}
int bytesToRead = 0;
byte[] pendingPacketBuffer = pendingPacket.getBuffer();
if (pendingPacketBuffer != null) {
int pendingPacketLength = pendingPacket.getLength();
bytesToRead = length > pendingPacketLength ? pendingPacketLength : length;
System.arraycopy(
pendingPacketBuffer, pendingPacket.getOffset(), buffer, offset, bytesToRead);
}
return bytesToRead;
}
/**
* Removes the RTX encapsulation from a packet.
*
* @param pkt the packet to remove the RTX encapsulation from.
* @return the original media packet represented by {@code pkt}, or null if we couldn't
* reconstruct the original packet.
*/
private RawPacket deRtx(RawPacket pkt) {
boolean success = false;
if (pkt.getPayloadLength() - pkt.getPaddingSize() < 2) {
// We need at least 2 bytes to read the OSN field.
if (logger.isDebugEnabled()) {
logger.debug("Dropping an incoming RTX packet with padding only: " + pkt);
}
return null;
}
long mediaSsrc = getPrimarySsrc(pkt);
if (mediaSsrc != -1) {
if (rtxAssociatedPayloadType != -1) {
int osn = pkt.getOriginalSequenceNumber();
// Remove the RTX header by moving the RTP header two bytes
// right.
byte[] buf = pkt.getBuffer();
int off = pkt.getOffset();
System.arraycopy(buf, off, buf, off + 2, pkt.getHeaderLength());
pkt.setOffset(off + 2);
pkt.setLength(pkt.getLength() - 2);
pkt.setSSRC((int) mediaSsrc);
pkt.setSequenceNumber(osn);
pkt.setPayloadType(rtxAssociatedPayloadType);
success = true;
} else {
logger.warn(
"RTX packet received, but no APT is defined. Packet "
+ "SSRC "
+ pkt.getSSRCAsLong()
+ ", associated media"
+ " SSRC "
+ mediaSsrc);
}
}
// If we failed to handle the RTX packet, drop it.
return success ? pkt : null;
}
/**
* Encapsulates {@code pkt} in the RTX format, using {@code rtxSsrc} as its SSRC, and transmits it
* to {@link #channel} by injecting it in the {@code MediaStream}.
*
* @param pkt the packet to transmit.
* @param rtxSsrc the SSRC for the RTX stream.
* @return {@code true} if the packet was successfully retransmitted, {@code false} otherwise.
*/
private boolean encapsulateInRtxAndTransmit(RawPacket pkt, long rtxSsrc) {
byte[] buf = pkt.getBuffer();
int len = pkt.getLength();
int off = pkt.getOffset();
byte[] newBuf = buf;
if (buf.length < len + 2) {
// FIXME The byte array newly allocated and assigned to newBuf must
// be made known to pkt eventually.
newBuf = new byte[len + 2];
}
int osn = pkt.getSequenceNumber();
int headerLength = pkt.getHeaderLength();
int payloadLength = len - headerLength;
System.arraycopy(buf, off, newBuf, 0, headerLength);
// FIXME If newBuf is actually buf, then we will override the first two
// bytes of the payload bellow.
newBuf[headerLength] = (byte) ((osn >> 8) & 0xff);
newBuf[headerLength + 1] = (byte) (osn & 0xff);
System.arraycopy(buf, off + headerLength, newBuf, headerLength + 2, payloadLength);
// FIXME We tried to extend the payload of pkt by two bytes above but
// we never told pkt that its length has increased by these two bytes.
MediaStream mediaStream = channel.getStream();
if (mediaStream != null) {
pkt.setSSRC((int) rtxSsrc);
// Only call getNextRtxSequenceNumber() when we're sure we're going
// to transmit a packet, because it consumes a sequence number.
pkt.setSequenceNumber(getNextRtxSequenceNumber(rtxSsrc));
try {
mediaStream.injectPacket(pkt, /* data */ true, /* after */ null);
} catch (TransmissionFailedException tfe) {
logger.warn("Failed to transmit an RTX packet.");
return false;
}
}
return true;
}
/**
* Encapsulates {@code pkt} in the RTX format, using {@code rtxSsrc} as its SSRC, and transmits it
* to {@link #channel} by injecting it in the {@code MediaStream}.
*
* @param pkt the packet to transmit.
* @param rtxSsrc the SSRC for the RTX stream.
* @param after the {@code TransformEngine} in the chain of {@code TransformEngine}s of the
* associated {@code MediaStream} after which the injection of {@code pkt} is to begin
* @return {@code true} if the packet was successfully retransmitted, {@code false} otherwise.
*/
private boolean encapsulateInRtxAndTransmit(RawPacket pkt, long rtxSsrc, TransformEngine after) {
byte[] buf = pkt.getBuffer();
int len = pkt.getLength();
int off = pkt.getOffset();
byte[] newBuf = new byte[len + 2];
RawPacket rtxPkt = new RawPacket(newBuf, 0, len + 2);
int osn = pkt.getSequenceNumber();
int headerLength = pkt.getHeaderLength();
int payloadLength = pkt.getPayloadLength();
// Copy the header.
System.arraycopy(buf, off, newBuf, 0, headerLength);
// Set the OSN field.
newBuf[headerLength] = (byte) ((osn >> 8) & 0xff);
newBuf[headerLength + 1] = (byte) (osn & 0xff);
// Copy the payload.
System.arraycopy(buf, off + headerLength, newBuf, headerLength + 2, payloadLength);
MediaStream mediaStream = channel.getStream();
if (mediaStream != null) {
rtxPkt.setSSRC((int) rtxSsrc);
rtxPkt.setPayloadType(rtxPayloadType);
// Only call getNextRtxSequenceNumber() when we're sure we're going
// to transmit a packet, because it consumes a sequence number.
rtxPkt.setSequenceNumber(getNextRtxSequenceNumber(rtxSsrc));
try {
mediaStream.injectPacket(rtxPkt, /* data */ true, after);
} catch (TransmissionFailedException tfe) {
logger.warn("Failed to transmit an RTX packet.");
return false;
}
}
return true;
}
private void runOnDtlsTransport(StreamConnector connector) throws IOException {
DtlsControlImpl dtlsControl = (DtlsControlImpl) getTransportManager().getDtlsControl(this);
DtlsTransformEngine engine = dtlsControl.getTransformEngine();
final DtlsPacketTransformer transformer = (DtlsPacketTransformer) engine.getRTPTransformer();
byte[] receiveBuffer = new byte[SCTP_BUFFER_SIZE];
if (LOG_SCTP_PACKETS) {
System.setProperty(
ConfigurationService.PNAME_SC_HOME_DIR_LOCATION, System.getProperty("java.io.tmpdir"));
System.setProperty(
ConfigurationService.PNAME_SC_HOME_DIR_NAME, SctpConnection.class.getName());
}
synchronized (this) {
// FIXME local SCTP port is hardcoded in bridge offer SDP (Jitsi
// Meet)
sctpSocket = Sctp.createSocket(5000);
assocIsUp = false;
acceptedIncomingConnection = false;
}
// Implement output network link for SCTP stack on DTLS transport
sctpSocket.setLink(
new NetworkLink() {
@Override
public void onConnOut(SctpSocket s, byte[] packet) throws IOException {
if (LOG_SCTP_PACKETS) {
LibJitsi.getPacketLoggingService()
.logPacket(
PacketLoggingService.ProtocolName.ICE4J,
new byte[] {0, 0, 0, (byte) debugId},
5000,
new byte[] {0, 0, 0, (byte) (debugId + 1)},
remoteSctpPort,
PacketLoggingService.TransportName.UDP,
true,
packet);
}
// Send through DTLS transport
transformer.sendApplicationData(packet, 0, packet.length);
}
});
if (logger.isDebugEnabled()) {
logger.debug("Connecting SCTP to port: " + remoteSctpPort + " to " + getEndpoint().getID());
}
sctpSocket.setNotificationListener(this);
sctpSocket.listen();
// FIXME manage threads
threadPool.execute(
new Runnable() {
@Override
public void run() {
SctpSocket sctpSocket = null;
try {
// sctpSocket is set to null on close
sctpSocket = SctpConnection.this.sctpSocket;
while (sctpSocket != null) {
if (sctpSocket.accept()) {
acceptedIncomingConnection = true;
break;
}
Thread.sleep(100);
sctpSocket = SctpConnection.this.sctpSocket;
}
if (isReady()) {
notifySctpConnectionReady();
}
} catch (Exception e) {
logger.error("Error accepting SCTP connection", e);
}
if (sctpSocket == null && logger.isInfoEnabled()) {
logger.info(
"SctpConnection " + getID() + " closed" + " before SctpSocket accept()-ed.");
}
}
});
// Notify that from now on SCTP connection is considered functional
sctpSocket.setDataCallback(this);
// Setup iceSocket
DatagramSocket datagramSocket = connector.getDataSocket();
if (datagramSocket != null) {
this.iceSocket = new IceUdpSocketWrapper(datagramSocket);
} else {
this.iceSocket = new IceTcpSocketWrapper(connector.getDataTCPSocket());
}
DatagramPacket rcvPacket = new DatagramPacket(receiveBuffer, 0, receiveBuffer.length);
// Receive loop, breaks when SCTP socket is closed
try {
do {
iceSocket.receive(rcvPacket);
RawPacket raw =
new RawPacket(rcvPacket.getData(), rcvPacket.getOffset(), rcvPacket.getLength());
raw = transformer.reverseTransform(raw);
// Check for app data
if (raw == null) continue;
if (LOG_SCTP_PACKETS) {
LibJitsi.getPacketLoggingService()
.logPacket(
PacketLoggingService.ProtocolName.ICE4J,
new byte[] {0, 0, 0, (byte) (debugId + 1)},
remoteSctpPort,
new byte[] {0, 0, 0, (byte) debugId},
5000,
PacketLoggingService.TransportName.UDP,
false,
raw.getBuffer(),
raw.getOffset(),
raw.getLength());
}
// Pass network packet to SCTP stack
sctpSocket.onConnIn(raw.getBuffer(), raw.getOffset(), raw.getLength());
} while (true);
} finally {
// Eventually, close the socket although it should happen from
// expire().
synchronized (this) {
assocIsUp = false;
acceptedIncomingConnection = false;
if (sctpSocket != null) {
sctpSocket.close();
sctpSocket = null;
}
}
}
}
/**
* Returns the value of the packet type field from the RTCP header of <tt>pkt</tt>. Assumes that
* <tt>pkt</tt> is a valid RTCP packet (at least as reported by {@link #isValidRTCP(RawPacket)}).
*
* @param pkt the packet to get the packet type of.
* @return the value of the packet type field from the RTCP header of <tt>pkt</tt>.
*/
private int getPacketType(RawPacket pkt) {
return pkt.getBuffer()[pkt.getOffset() + 1] & 0xff;
}
