/*
* Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 9406+5 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.security.ssl;
import java.io.*;
import java.nio.*;
import java.security.GeneralSecurityException;
import java.util.*;
import javax.crypto.BadPaddingException;
import javax.net.ssl.*;
import sun.security.ssl.SSLCipher.SSLReadCipher;
/**
* DTLS {@code InputRecord} implementation for {@code SSLEngine}.
*/
final class DTLSInputRecord extends InputRecord implements DTLSRecord {
private DTLSReassembler reassembler = null;
private int readEpoch;
DTLSInputRecord(HandshakeHash handshakeHash) {
super(handshakeHash, SSLReadCipher.nullDTlsReadCipher());
this.readEpoch = 0;
}
@Override
void changeReadCiphers(SSLReadCipher readCipher) {
this.readCipher = readCipher;
this.readEpoch++;
}
@Override
public synchronized void close() throws IOException {
if (!isClosed) {
super.close();
}
}
@Override
boolean isEmpty() {
return ((reassembler == null) || reassembler.isEmpty());
}
@Override
int estimateFragmentSize(int packetSize) {
if (packetSize > 0) {
return readCipher.estimateFragmentSize(packetSize, headerSize);
} else {
return Record.maxDataSize;
}
}
@Override
void expectingFinishFlight() {
if (reassembler != null) {
reassembler.expectingFinishFlight();
}
}
@Override
void finishHandshake() {
reassembler = null;
}
@Override
Plaintext acquirePlaintext() {
if (reassembler != null) {
return reassembler.acquirePlaintext();
}
return null;
}
@Override
Plaintext[] decode(ByteBuffer[] srcs, int srcsOffset,
int srcsLength) throws IOException, BadPaddingException {
if (srcs == null || srcs.length == 0 || srcsLength == 0) {
Plaintext pt = acquirePlaintext();
return pt == null ? new Plaintext[0] : new Plaintext[] { pt };
} else if (srcsLength == 1) {
return decode(srcs[srcsOffset]);
} else {
ByteBuffer packet = extract(srcs,
srcsOffset, srcsLength, DTLSRecord.headerSize);
return decode(packet);
}
}
Plaintext[] decode(ByteBuffer packet) {
if (isClosed) {
return null;
}
if (SSLLogger.isOn && SSLLogger.isOn("packet")) {
SSLLogger.fine("Raw read", packet);
}
// The caller should have validated the record.
int srcPos = packet.position();
int srcLim = packet.limit();
byte contentType = packet.get(); // pos: 0
byte majorVersion = packet.get(); // pos: 1
byte minorVersion = packet.get(); // pos: 2
byte[] recordEnS = new byte[8]; // epoch + seqence
packet.get(recordEnS);
int recordEpoch = ((recordEnS[0] & 0xFF) << 8) |
(recordEnS[1] & 0xFF); // pos: 3, 4
long recordSeq = ((recordEnS[2] & 0xFFL) << 40) |
((recordEnS[3] & 0xFFL) << 32) |
((recordEnS[4] & 0xFFL) << 24) |
((recordEnS[5] & 0xFFL) << 16) |
((recordEnS[6] & 0xFFL) << 8) |
(recordEnS[7] & 0xFFL); // pos: 5-10
int contentLen = ((packet.get() & 0xFF) << 8) |
(packet.get() & 0xFF); // pos: 11, 12
if (SSLLogger.isOn && SSLLogger.isOn("record")) {
SSLLogger.fine("READ: " +
ProtocolVersion.nameOf(majorVersion, minorVersion) +
" " + ContentType.nameOf(contentType) + ", length = " +
contentLen);
}
int recLim = srcPos + DTLSRecord.headerSize + contentLen;
if (this.readEpoch > recordEpoch) {
// Reset the position of the packet buffer.
packet.position(recLim);
if (SSLLogger.isOn && SSLLogger.isOn("record")) {
SSLLogger.fine("READ: discard this old record", recordEnS);
}
return null;
}
// Buffer next epoch message if necessary.
if (this.readEpoch < recordEpoch) {
// Discard the record younger than the current epcoh if:
// 1. it is not a handshake message, or
// 3. it is not of next epoch.
if ((contentType != ContentType.HANDSHAKE.id &&
contentType != ContentType.CHANGE_CIPHER_SPEC.id) ||
(reassembler == null &&
contentType != ContentType.HANDSHAKE.id) ||
(this.readEpoch < (recordEpoch - 1))) {
packet.position(recLim);
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("Premature record (epoch), discard it.");
}
return null;
}
// Not ready to decrypt this record, may be an encrypted Finished
// message, need to buffer it.
byte[] fragment = new byte[contentLen];
packet.get(fragment); // copy the fragment
RecordFragment buffered = new RecordFragment(fragment, contentType,
majorVersion, minorVersion,
recordEnS, recordEpoch, recordSeq, true);
if (reassembler == null) {
reassembler = new DTLSReassembler(recordEpoch);
}
reassembler.queueUpFragment(buffered);
// consume the full record in the packet buffer.
packet.position(recLim);
Plaintext pt = reassembler.acquirePlaintext();
return pt == null ? null : new Plaintext[] { pt };
}
//
// Now, the message is of this epoch.
//
// decrypt the fragment
packet.limit(recLim);
packet.position(srcPos + DTLSRecord.headerSize);
ByteBuffer plaintextFragment;
try {
Plaintext plaintext =
readCipher.decrypt(contentType, packet, recordEnS);
plaintextFragment = plaintext.fragment;
contentType = plaintext.contentType;
} catch (GeneralSecurityException gse) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl")) {
SSLLogger.fine("Discard invalid record: " + gse);
}
// invalid, discard this record [section 4.1.2.7, RFC 6347]
return null;
} finally {
// comsume a complete record
packet.limit(srcLim);
packet.position(recLim);
}
if (contentType != ContentType.CHANGE_CIPHER_SPEC.id &&
contentType != ContentType.HANDSHAKE.id) { // app data or alert
// no retransmission
// Cleanup the handshake reassembler if necessary.
if ((reassembler != null) &&
(reassembler.handshakeEpoch < recordEpoch)) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("Cleanup the handshake reassembler");
}
reassembler = null;
}
return new Plaintext[] {
new Plaintext(contentType, majorVersion, minorVersion,
recordEpoch, Authenticator.toLong(recordEnS),
plaintextFragment)};
}
if (contentType == ContentType.CHANGE_CIPHER_SPEC.id) {
if (reassembler == null) {
reassembler = new DTLSReassembler(recordEpoch);
}
reassembler.queueUpChangeCipherSpec(
new RecordFragment(plaintextFragment, contentType,
majorVersion, minorVersion,
recordEnS, recordEpoch, recordSeq, false));
} else { // handshake record
// One record may contain 1+ more handshake messages.
while (plaintextFragment.remaining() > 0) {
HandshakeFragment hsFrag = parseHandshakeMessage(
contentType, majorVersion, minorVersion,
recordEnS, recordEpoch, recordSeq, plaintextFragment);
if (hsFrag == null) {
// invalid, discard this record
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Invalid handshake message, discard it.");
}
return null;
}
if (reassembler == null) {
reassembler = new DTLSReassembler(recordEpoch);
}
reassembler.queueUpHandshake(hsFrag);
}
}
// Completed the read of the full record. Acquire the reassembled
// messages.
if (reassembler != null) {
Plaintext pt = reassembler.acquirePlaintext();
return pt == null ? null : new Plaintext[] { pt };
}
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("The reassembler is not initialized yet.");
}
return null;
}
@Override
int bytesInCompletePacket(
ByteBuffer[] srcs, int srcsOffset, int srcsLength) throws IOException {
return bytesInCompletePacket(srcs[srcsOffset]);
}
private int bytesInCompletePacket(ByteBuffer packet) throws SSLException {
// DTLS length field is in bytes 11/12
if (packet.remaining() < headerSize) {
return -1;
}
// Last sanity check that it's not a wild record
int pos = packet.position();
// Check the content type of the record.
byte contentType = packet.get(pos);
if (ContentType.valueOf(contentType) == null) {
throw new SSLException(
"Unrecognized SSL message, plaintext connection?");
}
// Check the protocol version of the record.
byte majorVersion = packet.get(pos + 1);
byte minorVersion = packet.get(pos + 2);
if (!ProtocolVersion.isNegotiable(
majorVersion, minorVersion, true, false)) {
throw new SSLException("Unrecognized record version " +
ProtocolVersion.nameOf(majorVersion, minorVersion) +
" , plaintext connection?");
}
// Get the fragment length of the record.
int fragLen = ((packet.get(pos + 11) & 0xFF) << 8) +
(packet.get(pos + 12) & 0xFF) + headerSize;
if (fragLen > Record.maxFragmentSize) {
throw new SSLException(
"Record overflow, fragment length (" + fragLen +
") MUST not exceed " + Record.maxFragmentSize);
}
return fragLen;
}
private static HandshakeFragment parseHandshakeMessage(
byte contentType, byte majorVersion, byte minorVersion,
byte[] recordEnS, int recordEpoch, long recordSeq,
ByteBuffer plaintextFragment) {
int remaining = plaintextFragment.remaining();
if (remaining < handshakeHeaderSize) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl")) {
SSLLogger.fine("Discard invalid record: " +
"too small record to hold a handshake fragment");
}
// invalid, discard this record [section 4.1.2.7, RFC 6347]
return null;
}
byte handshakeType = plaintextFragment.get(); // pos: 0
int messageLength =
((plaintextFragment.get() & 0xFF) << 16) |
((plaintextFragment.get() & 0xFF) << 8) |
(plaintextFragment.get() & 0xFF); // pos: 1-3
int messageSeq =
((plaintextFragment.get() & 0xFF) << 8) |
(plaintextFragment.get() & 0xFF); // pos: 4/5
int fragmentOffset =
((plaintextFragment.get() & 0xFF) << 16) |
((plaintextFragment.get() & 0xFF) << 8) |
(plaintextFragment.get() & 0xFF); // pos: 6-8
int fragmentLength =
((plaintextFragment.get() & 0xFF) << 16) |
((plaintextFragment.get() & 0xFF) << 8) |
(plaintextFragment.get() & 0xFF); // pos: 9-11
if ((remaining - handshakeHeaderSize) < fragmentLength) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl")) {
SSLLogger.fine("Discard invalid record: " +
"not a complete handshake fragment in the record");
}
// invalid, discard this record [section 4.1.2.7, RFC 6347]
return null;
}
byte[] fragment = new byte[fragmentLength];
plaintextFragment.get(fragment);
return new HandshakeFragment(fragment, contentType,
majorVersion, minorVersion,
recordEnS, recordEpoch, recordSeq,
handshakeType, messageLength,
messageSeq, fragmentOffset, fragmentLength);
}
// buffered record fragment
private static class RecordFragment implements Comparable<RecordFragment> {
boolean isCiphertext;
byte contentType;
byte majorVersion;
byte minorVersion;
int recordEpoch;
long recordSeq;
byte[] recordEnS;
byte[] fragment;
RecordFragment(ByteBuffer fragBuf, byte contentType,
byte majorVersion, byte minorVersion, byte[] recordEnS,
int recordEpoch, long recordSeq, boolean isCiphertext) {
this((byte[])null, contentType, majorVersion, minorVersion,
recordEnS, recordEpoch, recordSeq, isCiphertext);
this.fragment = new byte[fragBuf.remaining()];
fragBuf.get(this.fragment);
}
RecordFragment(byte[] fragment, byte contentType,
byte majorVersion, byte minorVersion, byte[] recordEnS,
int recordEpoch, long recordSeq, boolean isCiphertext) {
this.isCiphertext = isCiphertext;
this.contentType = contentType;
this.majorVersion = majorVersion;
this.minorVersion = minorVersion;
this.recordEpoch = recordEpoch;
this.recordSeq = recordSeq;
this.recordEnS = recordEnS;
this.fragment = fragment; // The caller should have cloned
// the buffer if necessary.
}
@Override
public int compareTo(RecordFragment o) {
if (this.contentType == ContentType.CHANGE_CIPHER_SPEC.id) {
if (o.contentType == ContentType.CHANGE_CIPHER_SPEC.id) {
// Only one incoming ChangeCipherSpec message for an epoch.
//
// Ignore duplicated ChangeCipherSpec messages.
return Integer.compare(this.recordEpoch, o.recordEpoch);
} else if ((this.recordEpoch == o.recordEpoch) &&
(o.contentType == ContentType.HANDSHAKE.id)) {
// ChangeCipherSpec is the latest message of an epoch.
return 1;
}
} else if (o.contentType == ContentType.CHANGE_CIPHER_SPEC.id) {
if ((this.recordEpoch == o.recordEpoch) &&
(this.contentType == ContentType.HANDSHAKE.id)) {
// ChangeCipherSpec is the latest message of an epoch.
return -1;
} else {
// different epoch or this is not a handshake message
return compareToSequence(o.recordEpoch, o.recordSeq);
}
}
return compareToSequence(o.recordEpoch, o.recordSeq);
}
int compareToSequence(int epoch, long seq) {
if (this.recordEpoch > epoch) {
return 1;
} else if (this.recordEpoch == epoch) {
return Long.compare(this.recordSeq, seq);
} else {
return -1;
}
}
}
// buffered handshake message
private static final class HandshakeFragment extends RecordFragment {
byte handshakeType; // handshake msg_type
int messageSeq; // message_seq
int messageLength; // Handshake body length
int fragmentOffset; // fragment_offset
int fragmentLength; // fragment_length
HandshakeFragment(byte[] fragment, byte contentType,
byte majorVersion, byte minorVersion, byte[] recordEnS,
int recordEpoch, long recordSeq,
byte handshakeType, int messageLength,
int messageSeq, int fragmentOffset, int fragmentLength) {
super(fragment, contentType, majorVersion, minorVersion,
recordEnS, recordEpoch , recordSeq, false);
this.handshakeType = handshakeType;
this.messageSeq = messageSeq;
this.messageLength = messageLength;
this.fragmentOffset = fragmentOffset;
this.fragmentLength = fragmentLength;
}
@Override
public int compareTo(RecordFragment o) {
if (o instanceof HandshakeFragment) {
HandshakeFragment other = (HandshakeFragment)o;
if (this.messageSeq != other.messageSeq) {
// keep the insertion order of handshake messages
return this.messageSeq - other.messageSeq;
} else if (this.fragmentOffset != other.fragmentOffset) {
// small fragment offset was transmitted first
return this.fragmentOffset - other.fragmentOffset;
} else if (this.fragmentLength == other.fragmentLength) {
// retransmissions, ignore duplicated messages.
return 0;
}
// Should be repacked for suitable fragment length.
//
// Note that the acquiring processes will reassemble the
// the fragments later.
return compareToSequence(o.recordEpoch, o.recordSeq);
}
return super.compareTo(o);
}
}
private static final class HoleDescriptor {
int offset; // fragment_offset
int limit; // fragment_offset + fragment_length
HoleDescriptor(int offset, int limit) {
this.offset = offset;
this.limit = limit;
}
}
private static final class HandshakeFlight implements Cloneable {
static final byte HF_UNKNOWN = SSLHandshake.NOT_APPLICABLE.id;
byte handshakeType; // handshake type
int flightEpoch; // the epoch of the first message
int minMessageSeq; // minimal message sequence
int maxMessageSeq; // maximum message sequence
int maxRecordEpoch; // maximum record sequence number
long maxRecordSeq; // maximum record sequence number
HashMap<Byte, List<HoleDescriptor>> holesMap;
HandshakeFlight() {
this.handshakeType = HF_UNKNOWN;
this.flightEpoch = 0;
this.minMessageSeq = 0;
this.maxMessageSeq = 0;
this.maxRecordEpoch = 0;
this.maxRecordSeq = -1;
this.holesMap = new HashMap<>(5);
}
boolean isRetransmitOf(HandshakeFlight hs) {
return (hs != null) &&
(this.handshakeType == hs.handshakeType) &&
(this.minMessageSeq == hs.minMessageSeq);
}
@Override
public Object clone() {
HandshakeFlight hf = new HandshakeFlight();
hf.handshakeType = this.handshakeType;
hf.flightEpoch = this.flightEpoch;
hf.minMessageSeq = this.minMessageSeq;
hf.maxMessageSeq = this.maxMessageSeq;
hf.maxRecordEpoch = this.maxRecordEpoch;
hf.maxRecordSeq = this.maxRecordSeq;
hf.holesMap = new HashMap<>(this.holesMap);
return hf;
}
}
final class DTLSReassembler {
// The handshake epoch.
final int handshakeEpoch;
// The buffered fragments.
TreeSet<RecordFragment> bufferedFragments = new TreeSet<>();
// The handshake flight in progress.
HandshakeFlight handshakeFlight = new HandshakeFlight();
// The preceding handshake flight.
HandshakeFlight precedingFlight = null;
// Epoch, sequence number and handshake message sequence of the
// next message acquisition of a flight.
int nextRecordEpoch; // next record epoch
long nextRecordSeq = 0; // next record sequence number
// Expect ChangeCipherSpec and Finished messages for the final flight.
boolean expectCCSFlight = false;
// Ready to process this flight if received all messages of the flight.
boolean flightIsReady = false;
boolean needToCheckFlight = false;
DTLSReassembler(int handshakeEpoch) {
this.handshakeEpoch = handshakeEpoch;
this.nextRecordEpoch = handshakeEpoch;
this.handshakeFlight.flightEpoch = handshakeEpoch;
}
void expectingFinishFlight() {
expectCCSFlight = true;
}
// Queue up a handshake message.
void queueUpHandshake(HandshakeFragment hsf) {
if (!isDesirable(hsf)) {
// Not a dedired record, discard it.
return;
}
// Clean up the retransmission messages if necessary.
cleanUpRetransmit(hsf);
// Is it the first message of next flight?
//
// Note: the Finished message is handled in the final CCS flight.
boolean isMinimalFlightMessage = false;
if (handshakeFlight.minMessageSeq == hsf.messageSeq) {
isMinimalFlightMessage = true;
} else if ((precedingFlight != null) &&
(precedingFlight.minMessageSeq == hsf.messageSeq)) {
isMinimalFlightMessage = true;
}
if (isMinimalFlightMessage && (hsf.fragmentOffset == 0) &&
(hsf.handshakeType != SSLHandshake.FINISHED.id)) {
// reset the handshake flight
handshakeFlight.handshakeType = hsf.handshakeType;
handshakeFlight.flightEpoch = hsf.recordEpoch;
handshakeFlight.minMessageSeq = hsf.messageSeq;
}
if (hsf.handshakeType == SSLHandshake.FINISHED.id) {
handshakeFlight.maxMessageSeq = hsf.messageSeq;
handshakeFlight.maxRecordEpoch = hsf.recordEpoch;
handshakeFlight.maxRecordSeq = hsf.recordSeq;
} else {
if (handshakeFlight.maxMessageSeq < hsf.messageSeq) {
handshakeFlight.maxMessageSeq = hsf.messageSeq;
}
int n = (hsf.recordEpoch - handshakeFlight.maxRecordEpoch);
if (n > 0) {
handshakeFlight.maxRecordEpoch = hsf.recordEpoch;
handshakeFlight.maxRecordSeq = hsf.recordSeq;
} else if (n == 0) {
// the same epoch
if (handshakeFlight.maxRecordSeq < hsf.recordSeq) {
handshakeFlight.maxRecordSeq = hsf.recordSeq;
}
} // Otherwise, it is unlikely to happen.
}
boolean fragmented = false;
if ((hsf.fragmentOffset) != 0 ||
(hsf.fragmentLength != hsf.messageLength)) {
fragmented = true;
}
List<HoleDescriptor> holes =
handshakeFlight.holesMap.get(hsf.handshakeType);
if (holes == null) {
if (!fragmented) {
holes = Collections.emptyList();
} else {
holes = new LinkedList<HoleDescriptor>();
holes.add(new HoleDescriptor(0, hsf.messageLength));
}
handshakeFlight.holesMap.put(hsf.handshakeType, holes);
} else if (holes.isEmpty()) {
// Have got the full handshake message. This record may be
// a handshake message retransmission. Discard this record.
//
// It's OK to discard retransmission as the handshake hash
// is computed as if each handshake message had been sent
// as a single fragment.
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("Have got the full message, discard it.");
}
return;
}
if (fragmented) {
int fragmentLimit = hsf.fragmentOffset + hsf.fragmentLength;
for (int i = 0; i < holes.size(); i++) {
HoleDescriptor hole = holes.get(i);
if ((hole.limit <= hsf.fragmentOffset) ||
(hole.offset >= fragmentLimit)) {
// Also discard overlapping handshake retransmissions.
continue;
}
// The ranges SHOULD NOT overlap.
if (((hole.offset > hsf.fragmentOffset) &&
(hole.offset < fragmentLimit)) ||
((hole.limit > hsf.fragmentOffset) &&
(hole.limit < fragmentLimit))) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl")) {
SSLLogger.fine("Discard invalid record: " +
"handshake fragment ranges are overlapping");
}
// invalid, discard it [section 4.1.2.7, RFC 6347]
return;
}
// This record interacts with this hole, fill the hole.
holes.remove(i);
// i--;
if (hsf.fragmentOffset > hole.offset) {
holes.add(new HoleDescriptor(
hole.offset, hsf.fragmentOffset));
// i++;
}
if (fragmentLimit < hole.limit) {
holes.add(new HoleDescriptor(
fragmentLimit, hole.limit));
// i++;
}
// As no ranges overlap, no interact with other holes.
break;
}
}
// buffer this fragment
if (hsf.handshakeType == SSLHandshake.FINISHED.id) {
// Need no status update.
bufferedFragments.add(hsf);
} else {
bufferFragment(hsf);
}
}
// Queue up a ChangeCipherSpec message
void queueUpChangeCipherSpec(RecordFragment rf) {
if (!isDesirable(rf)) {
// Not a dedired record, discard it.
return;
}
// Clean up the retransmission messages if necessary.
cleanUpRetransmit(rf);
// Is it the first message of this flight?
//
// Note: the first message of the final flight is ChangeCipherSpec.
if (expectCCSFlight) {
handshakeFlight.handshakeType = HandshakeFlight.HF_UNKNOWN;
handshakeFlight.flightEpoch = rf.recordEpoch;
}
// The epoch should be the same as the first message of the flight.
if (handshakeFlight.maxRecordSeq < rf.recordSeq) {
handshakeFlight.maxRecordSeq = rf.recordSeq;
}
// buffer this fragment
bufferFragment(rf);
}
// Queue up a ciphertext message.
//
// Note: not yet be able to decrypt the message.
void queueUpFragment(RecordFragment rf) {
if (!isDesirable(rf)) {
// Not a dedired record, discard it.
return;
}
// Clean up the retransmission messages if necessary.
cleanUpRetransmit(rf);
// buffer this fragment
bufferFragment(rf);
}
private void bufferFragment(RecordFragment rf) {
// append this fragment
bufferedFragments.add(rf);
if (flightIsReady) {
flightIsReady = false;
}
if (!needToCheckFlight) {
needToCheckFlight = true;
}
}
private void cleanUpRetransmit(RecordFragment rf) {
// Does the next flight start?
boolean isNewFlight = false;
if (precedingFlight != null) {
if (precedingFlight.flightEpoch < rf.recordEpoch) {
isNewFlight = true;
} else {
if (rf instanceof HandshakeFragment) {
HandshakeFragment hsf = (HandshakeFragment)rf;
if (precedingFlight.maxMessageSeq < hsf.messageSeq) {
isNewFlight = true;
}
} else if (
rf.contentType != ContentType.CHANGE_CIPHER_SPEC.id) {
// ciphertext
if (precedingFlight.maxRecordEpoch < rf.recordEpoch) {
isNewFlight = true;
}
}
}
}
if (!isNewFlight) {
// Need no cleanup.
return;
}
// clean up the buffer
for (Iterator<RecordFragment> it = bufferedFragments.iterator();
it.hasNext();) {
RecordFragment frag = it.next();
boolean isOld = false;
if (frag.recordEpoch < precedingFlight.maxRecordEpoch) {
isOld = true;
} else if (frag.recordEpoch == precedingFlight.maxRecordEpoch) {
if (frag.recordSeq <= precedingFlight.maxRecordSeq) {
isOld = true;
}
}
if (!isOld && (frag instanceof HandshakeFragment)) {
HandshakeFragment hsf = (HandshakeFragment)frag;
isOld = (hsf.messageSeq <= precedingFlight.maxMessageSeq);
}
if (isOld) {
it.remove();
} else {
// Safe to break as items in the buffer are ordered.
break;
}
}
// discard retransmissions of the previous flight if any.
precedingFlight = null;
}
// Is a desired record?
//
// Check for retransmission and lost records.
private boolean isDesirable(RecordFragment rf) {
//
// Discard records old than the previous epoch.
//
int previousEpoch = nextRecordEpoch - 1;
if (rf.recordEpoch < previousEpoch) {
// Too old to use, discard this record.
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Too old epoch to use this record, discard it.");
}
return false;
}
//
// Allow retransmission of last flight of the previous epoch
//
// For example, the last server delivered flight for session
// resuming abbreviated handshaking consist three messages:
// ServerHello
// [ChangeCipherSpec]
// Finished
//
// The epoch number is incremented and the sequence number is reset
// if the ChangeCipherSpec is sent.
if (rf.recordEpoch == previousEpoch) {
boolean isDesired = true;
if (precedingFlight == null) {
isDesired = false;
} else {
if (rf instanceof HandshakeFragment) {
HandshakeFragment hsf = (HandshakeFragment)rf;
if (precedingFlight.minMessageSeq > hsf.messageSeq) {
isDesired = false;
}
} else if (
rf.contentType == ContentType.CHANGE_CIPHER_SPEC.id) {
// ChangeCipherSpec
if (precedingFlight.flightEpoch != rf.recordEpoch) {
isDesired = false;
}
} else { // ciphertext
if ((rf.recordEpoch < precedingFlight.maxRecordEpoch) ||
(rf.recordEpoch == precedingFlight.maxRecordEpoch &&
rf.recordSeq <= precedingFlight.maxRecordSeq)) {
isDesired = false;
}
}
}
if (!isDesired) {
// Too old to use, discard this retransmitted record
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Too old retransmission to use, discard it.");
}
return false;
}
} else if ((rf.recordEpoch == nextRecordEpoch) &&
(nextRecordSeq > rf.recordSeq)) {
// Previously disordered record for the current epoch.
//
// Should has been retransmitted. Discard this record.
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Lagging behind record (sequence), discard it.");
}
return false;
}
return true;
}
private boolean isEmpty() {
return (bufferedFragments.isEmpty() ||
(!flightIsReady && !needToCheckFlight) ||
(needToCheckFlight && !flightIsReady()));
}
Plaintext acquirePlaintext() {
if (bufferedFragments.isEmpty()) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("No received handshake messages");
}
return null;
}
if (!flightIsReady && needToCheckFlight) {
// check the fligth status
flightIsReady = flightIsReady();
// Reset if this flight is ready.
if (flightIsReady) {
// Retransmitted handshake messages are not needed for
// further handshaking processing.
if (handshakeFlight.isRetransmitOf(precedingFlight)) {
// cleanup
bufferedFragments.clear();
// Reset the next handshake flight.
resetHandshakeFlight(precedingFlight);
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("Received a retransmission flight.");
}
return Plaintext.PLAINTEXT_NULL;
}
}
needToCheckFlight = false;
}
if (!flightIsReady) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"The handshake flight is not ready to use: " +
handshakeFlight.handshakeType);
}
return null;
}
RecordFragment rFrag = bufferedFragments.first();
Plaintext plaintext;
if (!rFrag.isCiphertext) {
// handshake message, or ChangeCipherSpec message
plaintext = acquireHandshakeMessage();
// Reset the handshake flight.
if (bufferedFragments.isEmpty()) {
// Need not to backup the holes map. Clear up it at first.
handshakeFlight.holesMap.clear(); // cleanup holes map
// Update the preceding flight.
precedingFlight = (HandshakeFlight)handshakeFlight.clone();
// Reset the next handshake flight.
resetHandshakeFlight(precedingFlight);
if (expectCCSFlight &&
(precedingFlight.handshakeType ==
HandshakeFlight.HF_UNKNOWN)) {
expectCCSFlight = false;
}
}
} else {
// a Finished message or other ciphertexts
plaintext = acquireCachedMessage();
}
return plaintext;
}
//
// Reset the handshake flight from a previous one.
//
private void resetHandshakeFlight(HandshakeFlight prev) {
// Reset the next handshake flight.
handshakeFlight.handshakeType = HandshakeFlight.HF_UNKNOWN;
handshakeFlight.flightEpoch = prev.maxRecordEpoch;
if (prev.flightEpoch != prev.maxRecordEpoch) {
// a new epoch starts
handshakeFlight.minMessageSeq = 0;
} else {
// stay at the same epoch
//
// The minimal message sequence number will get updated if
// a flight retransmission happens.
handshakeFlight.minMessageSeq = prev.maxMessageSeq + 1;
}
// cleanup the maximum sequence number and epoch number.
//
// Note: actually, we need to do nothing because the reassembler
// of handshake messages will reset them properly even for
// retransmissions.
//
handshakeFlight.maxMessageSeq = 0;
handshakeFlight.maxRecordEpoch = handshakeFlight.flightEpoch;
// Record sequence number cannot wrap even for retransmissions.
handshakeFlight.maxRecordSeq = prev.maxRecordSeq + 1;
// cleanup holes map
handshakeFlight.holesMap.clear();
// Ready to accept new input record.
flightIsReady = false;
needToCheckFlight = false;
}
private Plaintext acquireCachedMessage() {
RecordFragment rFrag = bufferedFragments.first();
if (readEpoch != rFrag.recordEpoch) {
if (readEpoch > rFrag.recordEpoch) {
// discard old records
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Discard old buffered ciphertext fragments.");
}
bufferedFragments.remove(rFrag); // popup the fragment
}
// reset the flight
if (flightIsReady) {
flightIsReady = false;
}
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Not yet ready to decrypt the cached fragments.");
}
return null;
}
bufferedFragments.remove(rFrag); // popup the fragment
ByteBuffer fragment = ByteBuffer.wrap(rFrag.fragment);
ByteBuffer plaintextFragment = null;
try {
Plaintext plaintext = readCipher.decrypt(
rFrag.contentType, fragment, rFrag.recordEnS);
plaintextFragment = plaintext.fragment;
rFrag.contentType = plaintext.contentType;
} catch (GeneralSecurityException gse) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("Discard invalid record: ", gse);
}
// invalid, discard this record [section 4.1.2.7, RFC 6347]
return null;
}
// The ciphtext handshake message can only be Finished (the
// end of this flight), ClinetHello or HelloRequest (the
// beginning of the next flight) message. Need not to check
// any ChangeCipherSpec message.
if (rFrag.contentType == ContentType.HANDSHAKE.id) {
while (plaintextFragment.remaining() > 0) {
HandshakeFragment hsFrag = parseHandshakeMessage(
rFrag.contentType,
rFrag.majorVersion, rFrag.minorVersion,
rFrag.recordEnS, rFrag.recordEpoch, rFrag.recordSeq,
plaintextFragment);
if (hsFrag == null) {
// invalid, discard this record
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Invalid handshake fragment, discard it",
plaintextFragment);
}
return null;
}
queueUpHandshake(hsFrag);
// The flight ready status (flightIsReady) should have
// been checked and updated for the Finished handshake
// message before the decryption. Please don't update
// flightIsReady for Finished messages.
if (hsFrag.handshakeType != SSLHandshake.FINISHED.id) {
flightIsReady = false;
needToCheckFlight = true;
}
}
return acquirePlaintext();
} else {
return new Plaintext(rFrag.contentType,
rFrag.majorVersion, rFrag.minorVersion,
rFrag.recordEpoch,
Authenticator.toLong(rFrag.recordEnS),
plaintextFragment);
}
}
private Plaintext acquireHandshakeMessage() {
RecordFragment rFrag = bufferedFragments.first();
if (rFrag.contentType == ContentType.CHANGE_CIPHER_SPEC.id) {
this.nextRecordEpoch = rFrag.recordEpoch + 1;
// For retransmissions, the next record sequence number is a
// positive value. Don't worry about it as the acquiring of
// the immediately followed Finished handshake message will
// reset the next record sequence number correctly.
this.nextRecordSeq = 0;
// Popup the fragment.
bufferedFragments.remove(rFrag);
return new Plaintext(rFrag.contentType,
rFrag.majorVersion, rFrag.minorVersion,
rFrag.recordEpoch,
Authenticator.toLong(rFrag.recordEnS),
ByteBuffer.wrap(rFrag.fragment));
} else { // rFrag.contentType == ContentType.HANDSHAKE.id
HandshakeFragment hsFrag = (HandshakeFragment)rFrag;
if ((hsFrag.messageLength == hsFrag.fragmentLength) &&
(hsFrag.fragmentOffset == 0)) { // no fragmentation
bufferedFragments.remove(rFrag); // popup the fragment
// this.nextRecordEpoch = hsFrag.recordEpoch;
this.nextRecordSeq = hsFrag.recordSeq + 1;
// Note: may try to avoid byte array copy in the future.
byte[] recordFrag = new byte[hsFrag.messageLength + 4];
Plaintext plaintext = new Plaintext(
hsFrag.contentType,
hsFrag.majorVersion, hsFrag.minorVersion,
hsFrag.recordEpoch,
Authenticator.toLong(hsFrag.recordEnS),
ByteBuffer.wrap(recordFrag));
// fill the handshake fragment of the record
recordFrag[0] = hsFrag.handshakeType;
recordFrag[1] =
(byte)((hsFrag.messageLength >>> 16) & 0xFF);
recordFrag[2] =
(byte)((hsFrag.messageLength >>> 8) & 0xFF);
recordFrag[3] = (byte)(hsFrag.messageLength & 0xFF);
System.arraycopy(hsFrag.fragment, 0,
recordFrag, 4, hsFrag.fragmentLength);
// handshake hashing
handshakeHashing(hsFrag, plaintext);
return plaintext;
} else { // fragmented handshake message
// the first record
//
// Note: may try to avoid byte array copy in the future.
byte[] recordFrag = new byte[hsFrag.messageLength + 4];
Plaintext plaintext = new Plaintext(
hsFrag.contentType,
hsFrag.majorVersion, hsFrag.minorVersion,
hsFrag.recordEpoch,
Authenticator.toLong(hsFrag.recordEnS),
ByteBuffer.wrap(recordFrag));
// fill the handshake fragment of the record
recordFrag[0] = hsFrag.handshakeType;
recordFrag[1] =
(byte)((hsFrag.messageLength >>> 16) & 0xFF);
recordFrag[2] =
(byte)((hsFrag.messageLength >>> 8) & 0xFF);
recordFrag[3] = (byte)(hsFrag.messageLength & 0xFF);
int msgSeq = hsFrag.messageSeq;
long maxRecodeSN = hsFrag.recordSeq;
HandshakeFragment hmFrag = hsFrag;
do {
System.arraycopy(hmFrag.fragment, 0,
recordFrag, hmFrag.fragmentOffset + 4,
hmFrag.fragmentLength);
// popup the fragment
bufferedFragments.remove(rFrag);
if (maxRecodeSN < hmFrag.recordSeq) {
maxRecodeSN = hmFrag.recordSeq;
}
// Note: may buffer retransmitted fragments in order to
// speed up the reassembly in the future.
// read the next buffered record
if (!bufferedFragments.isEmpty()) {
rFrag = bufferedFragments.first();
if (rFrag.contentType != ContentType.HANDSHAKE.id) {
break;
} else {
hmFrag = (HandshakeFragment)rFrag;
}
}
} while (!bufferedFragments.isEmpty() &&
(msgSeq == hmFrag.messageSeq));
// handshake hashing
handshakeHashing(hsFrag, plaintext);
this.nextRecordSeq = maxRecodeSN + 1;
return plaintext;
}
}
}
boolean flightIsReady() {
byte flightType = handshakeFlight.handshakeType;
if (flightType == HandshakeFlight.HF_UNKNOWN) {
//
// the ChangeCipherSpec/Finished flight
//
if (expectCCSFlight) {
// Have the ChangeCipherSpec/Finished flight been received?
boolean isReady = hasFinishedMessage(bufferedFragments);
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Has the final flight been received? " + isReady);
}
return isReady;
}
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("No flight is received yet.");
}
return false;
}
if ((flightType == SSLHandshake.CLIENT_HELLO.id) ||
(flightType == SSLHandshake.HELLO_REQUEST.id) ||
(flightType == SSLHandshake.HELLO_VERIFY_REQUEST.id)) {
// single handshake message flight
boolean isReady = hasCompleted(flightType);
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Is the handshake message completed? " + isReady);
}
return isReady;
}
//
// the ServerHello flight
//
if (flightType == SSLHandshake.SERVER_HELLO.id) {
// Firstly, check the first flight handshake message.
if (!hasCompleted(flightType)) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"The ServerHello message is not completed yet.");
}
return false;
}
//
// an abbreviated handshake
//
if (hasFinishedMessage(bufferedFragments)) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("It's an abbreviated handshake.");
}
return true;
}
//
// a full handshake
//
List<HoleDescriptor> holes = handshakeFlight.holesMap.get(
SSLHandshake.SERVER_HELLO_DONE.id);
if ((holes == null) || !holes.isEmpty()) {
// Not yet got the final message of the flight.
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Not yet got the ServerHelloDone message");
}
return false;
}
// Have all handshake message been received?
boolean isReady = hasCompleted(bufferedFragments,
handshakeFlight.minMessageSeq,
handshakeFlight.maxMessageSeq);
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Is the ServerHello flight (message " +
handshakeFlight.minMessageSeq + "-" +
handshakeFlight.maxMessageSeq +
") completed? " + isReady);
}
return isReady;
}
//
// the ClientKeyExchange flight
//
// Note: need to consider more messages in this flight if
// ht_supplemental_data and ht_certificate_url are
// suppported in the future.
//
if ((flightType == SSLHandshake.CERTIFICATE.id) ||
(flightType == SSLHandshake.CLIENT_KEY_EXCHANGE.id)) {
// Firstly, check the first flight handshake message.
if (!hasCompleted(flightType)) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"The ClientKeyExchange or client Certificate " +
"message is not completed yet.");
}
return false;
}
// Is client CertificateVerify a mandatory message?
if (flightType == SSLHandshake.CERTIFICATE.id) {
if (needClientVerify(bufferedFragments) &&
!hasCompleted(SSLHandshake.CERTIFICATE_VERIFY.id)) {
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Not yet have the CertificateVerify message");
}
return false;
}
}
if (!hasFinishedMessage(bufferedFragments)) {
// not yet have the ChangeCipherSpec/Finished messages
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Not yet have the ChangeCipherSpec and " +
"Finished messages");
}
return false;
}
// Have all handshake message been received?
boolean isReady = hasCompleted(bufferedFragments,
handshakeFlight.minMessageSeq,
handshakeFlight.maxMessageSeq);
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine(
"Is the ClientKeyExchange flight (message " +
handshakeFlight.minMessageSeq + "-" +
handshakeFlight.maxMessageSeq +
") completed? " + isReady);
}
return isReady;
}
//
// Otherwise, need to receive more handshake messages.
//
if (SSLLogger.isOn && SSLLogger.isOn("verbose")) {
SSLLogger.fine("Need to receive more handshake messages");
}
return false;
}
// Looking for the ChangeCipherSpec and Finished messages.
//
// As the cached Finished message should be a ciphertext, we don't
// exactly know a ciphertext is a Finished message or not. According
// to the spec of TLS/DTLS handshaking, a Finished message is always
// sent immediately after a ChangeCipherSpec message. The first
// ciphertext handshake message should be the expected Finished message.
private boolean hasFinishedMessage(Set<RecordFragment> fragments) {
boolean hasCCS = false;
boolean hasFin = false;
for (RecordFragment fragment : fragments) {
if (fragment.contentType == ContentType.CHANGE_CIPHER_SPEC.id) {
if (hasFin) {
return true;
}
hasCCS = true;
} else if (fragment.contentType == ContentType.HANDSHAKE.id) {
// Finished is the first expected message of a new epoch.
if (fragment.isCiphertext) {
if (hasCCS) {
return true;
}
hasFin = true;
}
}
}
return hasFin && hasCCS;
}
// Is client CertificateVerify a mandatory message?
//
// In the current implementation, client CertificateVerify is a
// mandatory message if the client Certificate is not empty.
private boolean needClientVerify(Set<RecordFragment> fragments) {
// The caller should have checked the completion of the first
// present handshake message. Need not to check it again.
for (RecordFragment rFrag : fragments) {
if ((rFrag.contentType != ContentType.HANDSHAKE.id) ||
rFrag.isCiphertext) {
break;
}
HandshakeFragment hsFrag = (HandshakeFragment)rFrag;
if (hsFrag.handshakeType != SSLHandshake.CERTIFICATE.id) {
continue;
}
return (rFrag.fragment != null) &&
(rFrag.fragment.length > DTLSRecord.minCertPlaintextSize);
}
return false;
}
private boolean hasCompleted(byte handshakeType) {
List<HoleDescriptor> holes =
handshakeFlight.holesMap.get(handshakeType);
if (holes == null) {
// not yet received this kind of handshake message
return false;
}
return holes.isEmpty(); // no fragment hole for complete message
}
private boolean hasCompleted(
Set<RecordFragment> fragments,
int presentMsgSeq, int endMsgSeq) {
// The caller should have checked the completion of the first
// present handshake message. Need not to check it again.
for (RecordFragment rFrag : fragments) {
if ((rFrag.contentType != ContentType.HANDSHAKE.id) ||
rFrag.isCiphertext) {
break;
}
HandshakeFragment hsFrag = (HandshakeFragment)rFrag;
if (hsFrag.messageSeq == presentMsgSeq) {
continue;
} else if (hsFrag.messageSeq == (presentMsgSeq + 1)) {
// check the completion of the handshake message
if (!hasCompleted(hsFrag.handshakeType)) {
return false;
}
presentMsgSeq = hsFrag.messageSeq;
} else {
// not yet got handshake message next to presentMsgSeq
break;
}
}
return (presentMsgSeq >= endMsgSeq);
// false: if not yet got all messages of the flight.
}
private void handshakeHashing(
HandshakeFragment hsFrag, Plaintext plaintext) {
byte hsType = hsFrag.handshakeType;
if (!handshakeHash.isHashable(hsType)) {
// omitted from handshake hash computation
return;
}
// calculate the DTLS header and reserve the handshake message
plaintext.fragment.position(4); // ignore the TLS header
byte[] temporary = new byte[plaintext.fragment.remaining() + 12];
// 12: handshake header size
// Handshake.msg_type
temporary[0] = hsFrag.handshakeType;
// Handshake.length
temporary[1] = (byte)((hsFrag.messageLength >> 16) & 0xFF);
temporary[2] = (byte)((hsFrag.messageLength >> 8) & 0xFF);
temporary[3] = (byte)(hsFrag.messageLength & 0xFF);
// Handshake.message_seq
temporary[4] = (byte)((hsFrag.messageSeq >> 8) & 0xFF);
temporary[5] = (byte)(hsFrag.messageSeq & 0xFF);
// Handshake.fragment_offset
temporary[6] = 0;
temporary[7] = 0;
temporary[8] = 0;
// Handshake.fragment_length
temporary[9] = temporary[1];
temporary[10] = temporary[2];
temporary[11] = temporary[3];
plaintext.fragment.get(temporary,
12, plaintext.fragment.remaining());
handshakeHash.receive(temporary);
plaintext.fragment.position(0); // restore the position
}
}
}