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/*
* Copyright (c) 2015, 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 94065 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.util.*;
import javax.crypto.BadPaddingException;
import javax.net.ssl.*;
import sun.misc.HexDumpEncoder;
import static sun.security.ssl.HandshakeMessage.*;
/**
* DTLS {@code InputRecord} implementation for {@code SSLEngine}.
*/
final class DTLSInputRecord extends InputRecord implements DTLSRecord {
private DTLSReassembler reassembler = null;
// Cache the session identifier for the detection of session-resuming
// handshake.
byte[] prevSessionID = new byte[0];
int readEpoch;
int prevReadEpoch;
Authenticator prevReadAuthenticator;
CipherBox prevReadCipher;
DTLSInputRecord() {
this.readEpoch = 0;
this.readAuthenticator = new MAC(true);
this.prevReadEpoch = 0;
this.prevReadCipher = CipherBox.NULL;
this.prevReadAuthenticator = new MAC(true);
}
@Override
void changeReadCiphers(Authenticator readAuthenticator,
CipherBox readCipher) {
prevReadCipher.dispose();
this.prevReadAuthenticator = this.readAuthenticator;
this.prevReadCipher = this.readCipher;
this.prevReadEpoch = this.readEpoch;
this.readAuthenticator = readAuthenticator;
this.readCipher = readCipher;
this.readEpoch++;
}
@Override
public synchronized void close() throws IOException {
if (!isClosed) {
prevReadCipher.dispose();
super.close();
}
}
@Override
boolean isEmpty() {
return ((reassembler == null) || reassembler.isEmpty());
}
@Override
int estimateFragmentSize(int packetSize) {
int macLen = 0;
if (readAuthenticator instanceof MAC) {
macLen = ((MAC)readAuthenticator).MAClen();
}
if (packetSize > 0) {
return readCipher.estimateFragmentSize(
packetSize, macLen, headerSize);
} else {
return Record.maxDataSize;
}
}
@Override
void expectingFinishFlight() {
if (reassembler != null) {
reassembler.expectingFinishFlight();
}
}
@Override
Plaintext acquirePlaintext() {
if (reassembler != null) {
Plaintext plaintext = reassembler.acquirePlaintext();
if (reassembler.finished()) {
// discard all buffered unused message.
reassembler = null;
}
return plaintext;
}
return null;
}
@Override
Plaintext decode(ByteBuffer packet) {
if (isClosed) {
return null;
}
if (debug != null && Debug.isOn("packet")) {
Debug.printHex(
"[Raw read]: length = " + packet.remaining(), 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 = Authenticator.toLong(recordEnS);
int contentLen = ((packet.get() & 0xFF) << 8) |
(packet.get() & 0xFF); // pos: 11, 12
if (debug != null && Debug.isOn("record")) {
System.out.println(Thread.currentThread().getName() +
", READ: " +
ProtocolVersion.valueOf(majorVersion, minorVersion) +
" " + Record.contentName(contentType) + ", length = " +
contentLen);
}
int recLim = srcPos + DTLSRecord.headerSize + contentLen;
if (this.readEpoch > recordEpoch) {
// Discard old records delivered before this epoch.
// Reset the position of the packet buffer.
packet.position(recLim);
return null;
}
if (this.readEpoch < recordEpoch) {
if (contentType != Record.ct_handshake) {
// just discard it if not a handshake message
packet.position(recLim);
return null;
}
// Not ready to decrypt this record, may be encrypted Finished
// message, need to buffer it.
if (reassembler == null) {
reassembler = new DTLSReassembler();
}
byte[] fragment = new byte[contentLen];
packet.get(fragment); // copy the fragment
RecordFragment buffered = new RecordFragment(fragment, contentType,
majorVersion, minorVersion,
recordEnS, recordEpoch, recordSeq, true);
reassembler.queueUpFragment(buffered);
// consume the full record in the packet buffer.
packet.position(recLim);
Plaintext plaintext = reassembler.acquirePlaintext();
if (reassembler.finished()) {
// discard all buffered unused message.
reassembler = null;
}
return plaintext;
}
if (this.readEpoch == recordEpoch) {
// decrypt the fragment
packet.limit(recLim);
packet.position(srcPos + DTLSRecord.headerSize);
ByteBuffer plaintextFragment;
try {
plaintextFragment = decrypt(readAuthenticator,
readCipher, contentType, packet, recordEnS);
} catch (BadPaddingException bpe) {
if (debug != null && Debug.isOn("ssl")) {
System.out.println(Thread.currentThread().getName() +
" discard invalid record: " + bpe);
}
// 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 != Record.ct_change_cipher_spec &&
contentType != Record.ct_handshake) { // app data or alert
// no retransmission
return new Plaintext(contentType, majorVersion, minorVersion,
recordEpoch, recordSeq, plaintextFragment);
}
if (contentType == Record.ct_change_cipher_spec) {
if (reassembler == null) {
// handshake has not started, should be an
// old handshake message, discard it.
return null;
}
reassembler.queueUpFragment(
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
return null;
}
if ((reassembler == null) &&
isKickstart(hsFrag.handshakeType)) {
reassembler = new DTLSReassembler();
}
if (reassembler != null) {
reassembler.queueUpHandshake(hsFrag);
} // else, just ignore the message.
}
}
// Completed the read of the full record. Acquire the reassembled
// messages.
if (reassembler != null) {
Plaintext plaintext = reassembler.acquirePlaintext();
if (reassembler.finished()) {
// discard all buffered unused message.
reassembler = null;
}
return plaintext;
}
}
return null; // make the complier happy
}
@Override
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 (!Record.isValidContentType(contentType)) {
throw new SSLException(
"Unrecognized SSL message, plaintext connection?");
}
// Check the protocol version of the record.
ProtocolVersion recordVersion =
ProtocolVersion.valueOf(packet.get(pos + 1), packet.get(pos + 2));
checkRecordVersion(recordVersion, false);
// 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;
}
@Override
void checkRecordVersion(ProtocolVersion recordVersion,
boolean allowSSL20Hello) throws SSLException {
if (!recordVersion.maybeDTLSProtocol()) {
throw new SSLException(
"Unrecognized record version " + recordVersion +
" , plaintext connection?");
}
}
private static boolean isKickstart(byte handshakeType) {
return (handshakeType == HandshakeMessage.ht_client_hello) ||
(handshakeType == HandshakeMessage.ht_hello_request) ||
(handshakeType == HandshakeMessage.ht_hello_verify_request);
}
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 (debug != null && Debug.isOn("ssl")) {
System.out.println(
Thread.currentThread().getName() +
" 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 (debug != null && Debug.isOn("ssl")) {
System.out.println(
Thread.currentThread().getName() +
" 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) {
return Long.compareUnsigned(this.recordSeq, o.recordSeq);
}
}
// 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 for the same message
return this.messageSeq - other.messageSeq;
}
}
return Long.compareUnsigned(this.recordSeq, o.recordSeq);
}
}
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;
}
}
final class DTLSReassembler {
TreeSet<RecordFragment> bufferedFragments = new TreeSet<>();
HashMap<Byte, List<HoleDescriptor>> holesMap = new HashMap<>(5);
// Epoch, sequence number and handshake message sequence of the
// beginning message of a flight.
byte flightType = (byte)0xFF;
int flightTopEpoch = 0;
long flightTopRecordSeq = -1;
int flightTopMessageSeq = 0;
// Epoch, sequence number and handshake message sequence of the
// next message acquisition of a flight.
int nextRecordEpoch = 0; // next record epoch
long nextRecordSeq = 0; // next record sequence number
int nextMessageSeq = 0; // next handshake message 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;
// Is it a session-resuming abbreviated handshake.?
boolean isAbbreviatedHandshake = false;
// The handshke fragment with the biggest record sequence number
// in a flight, not counting the Finished message.
HandshakeFragment lastHandshakeFragment = null;
// Is handshake (intput) finished?
boolean handshakeFinished = false;
DTLSReassembler() {
// blank
}
boolean finished() {
return handshakeFinished;
}
void expectingFinishFlight() {
expectCCSFlight = true;
}
void queueUpHandshake(HandshakeFragment hsf) {
if ((nextRecordEpoch > hsf.recordEpoch) ||
(nextRecordSeq > hsf.recordSeq) ||
(nextMessageSeq > hsf.messageSeq)) {
// too old, discard this record
return;
}
// Is it the first message of next flight?
if ((flightTopMessageSeq == hsf.messageSeq) &&
(hsf.fragmentOffset == 0) && (flightTopRecordSeq == -1)) {
flightType = hsf.handshakeType;
flightTopEpoch = hsf.recordEpoch;
flightTopRecordSeq = hsf.recordSeq;
if (hsf.handshakeType == HandshakeMessage.ht_server_hello) {
// Is it a session-resuming handshake?
try {
isAbbreviatedHandshake =
isSessionResuming(hsf.fragment, prevSessionID);
} catch (SSLException ssle) {
if (debug != null && Debug.isOn("ssl")) {
System.out.println(
Thread.currentThread().getName() +
" discard invalid record: " + ssle);
}
// invalid, discard it [section 4.1.2.7, RFC 6347]
return;
}
if (!isAbbreviatedHandshake) {
prevSessionID = getSessionID(hsf.fragment);
}
}
}
boolean fragmented = false;
if ((hsf.fragmentOffset) != 0 ||
(hsf.fragmentLength != hsf.messageLength)) {
fragmented = true;
}
List<HoleDescriptor> holes = holesMap.get(hsf.handshakeType);
if (holes == null) {
if (!fragmented) {
holes = Collections.emptyList();
} else {
holes = new LinkedList<HoleDescriptor>();
holes.add(new HoleDescriptor(0, hsf.messageLength));
}
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.
//
// Note that ClientHello messages are delivered twice in
// DTLS handshaking.
if ((hsf.handshakeType != HandshakeMessage.ht_client_hello &&
hsf.handshakeType != ht_hello_verify_request) ||
(nextMessageSeq != hsf.messageSeq)) {
return;
}
if (fragmented) {
holes = new LinkedList<HoleDescriptor>();
holes.add(new HoleDescriptor(0, hsf.messageLength));
}
holesMap.put(hsf.handshakeType, holes);
}
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 (debug != null && Debug.isOn("ssl")) {
System.out.println(
Thread.currentThread().getName() +
" 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;
}
}
// append this fragment
bufferedFragments.add(hsf);
if ((lastHandshakeFragment == null) ||
(lastHandshakeFragment.compareTo(hsf) < 0)) {
lastHandshakeFragment = hsf;
}
if (flightIsReady) {
flightIsReady = false;
}
needToCheckFlight = true;
}
// queue up change_cipher_spec or encrypted message
void queueUpFragment(RecordFragment rf) {
if ((nextRecordEpoch > rf.recordEpoch) ||
(nextRecordSeq > rf.recordSeq)) {
// too old, discard this record
return;
}
// Is it the first message of next flight?
if (expectCCSFlight &&
(rf.contentType == Record.ct_change_cipher_spec)) {
flightType = (byte)0xFE;
flightTopEpoch = rf.recordEpoch;
flightTopRecordSeq = rf.recordSeq;
}
// append this fragment
bufferedFragments.add(rf);
if (flightIsReady) {
flightIsReady = false;
}
needToCheckFlight = true;
}
boolean isEmpty() {
return (bufferedFragments.isEmpty() ||
(!flightIsReady && !needToCheckFlight) ||
(needToCheckFlight && !flightIsReady()));
}
Plaintext acquirePlaintext() {
if (bufferedFragments.isEmpty()) {
// reset the flight
if (flightIsReady) {
flightIsReady = false;
needToCheckFlight = false;
}
return null;
}
if (!flightIsReady && needToCheckFlight) {
// check the fligth status
flightIsReady = flightIsReady();
// set for next flight
if (flightIsReady) {
flightTopMessageSeq = lastHandshakeFragment.messageSeq + 1;
flightTopRecordSeq = -1;
}
needToCheckFlight = false;
}
if (!flightIsReady) {
return null;
}
RecordFragment rFrag = bufferedFragments.first();
if (!rFrag.isCiphertext) {
// handshake message, or ChangeCipherSpec message
return acquireHandshakeMessage();
} else {
// a Finished message or other ciphertexts
return acquireCachedMessage();
}
}
private Plaintext acquireCachedMessage() {
RecordFragment rFrag = bufferedFragments.first();
if (readEpoch != rFrag.recordEpoch) {
if (readEpoch > rFrag.recordEpoch) {
// discard old records
bufferedFragments.remove(rFrag); // popup the fragment
}
// reset the flight
if (flightIsReady) {
flightIsReady = false;
}
return null;
}
bufferedFragments.remove(rFrag); // popup the fragment
ByteBuffer fragment = ByteBuffer.wrap(rFrag.fragment);
ByteBuffer plaintextFragment = null;
try {
plaintextFragment = decrypt(readAuthenticator, readCipher,
rFrag.contentType, fragment, rFrag.recordEnS);
} catch (BadPaddingException bpe) {
if (debug != null && Debug.isOn("ssl")) {
System.out.println(Thread.currentThread().getName() +
" discard invalid record: " + bpe);
}
// 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 == Record.ct_handshake) {
HandshakeFragment finFrag = null;
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
return null;
}
if (hsFrag.handshakeType == HandshakeMessage.ht_finished) {
finFrag = hsFrag;
// reset for the next flight
this.flightType = (byte)0xFF;
this.flightTopEpoch = rFrag.recordEpoch;
this.flightTopMessageSeq = hsFrag.messageSeq + 1;
this.flightTopRecordSeq = -1;
} else {
// reset the flight
if (flightIsReady) {
flightIsReady = false;
}
queueUpHandshake(hsFrag);
}
}
this.nextRecordSeq = rFrag.recordSeq + 1;
this.nextMessageSeq = 0;
if (finFrag != null) {
this.nextRecordEpoch = finFrag.recordEpoch;
this.nextRecordSeq = finFrag.recordSeq + 1;
this.nextMessageSeq = finFrag.messageSeq + 1;
// Finished message does not fragment.
byte[] recordFrag = new byte[finFrag.messageLength + 4];
Plaintext plaintext = new Plaintext(finFrag.contentType,
finFrag.majorVersion, finFrag.minorVersion,
finFrag.recordEpoch, finFrag.recordSeq,
ByteBuffer.wrap(recordFrag));
// fill the handshake fragment of the record
recordFrag[0] = finFrag.handshakeType;
recordFrag[1] =
(byte)((finFrag.messageLength >>> 16) & 0xFF);
recordFrag[2] =
(byte)((finFrag.messageLength >>> 8) & 0xFF);
recordFrag[3] = (byte)(finFrag.messageLength & 0xFF);
System.arraycopy(finFrag.fragment, 0,
recordFrag, 4, finFrag.fragmentLength);
// handshake hashing
handshakeHashing(finFrag, plaintext);
// input handshake finished
handshakeFinished = true;
return plaintext;
} else {
return acquirePlaintext();
}
} else {
return new Plaintext(rFrag.contentType,
rFrag.majorVersion, rFrag.minorVersion,
rFrag.recordEpoch, rFrag.recordSeq,
plaintextFragment);
}
}
private Plaintext acquireHandshakeMessage() {
RecordFragment rFrag = bufferedFragments.first();
if (rFrag.contentType == Record.ct_change_cipher_spec) {
this.nextRecordEpoch = rFrag.recordEpoch + 1;
this.nextRecordSeq = 0;
// no change on next handshake message sequence number
bufferedFragments.remove(rFrag); // popup the fragment
// Reload if this message has been reserved for handshake hash.
handshakeHash.reload();
return new Plaintext(rFrag.contentType,
rFrag.majorVersion, rFrag.minorVersion,
rFrag.recordEpoch, rFrag.recordSeq,
ByteBuffer.wrap(rFrag.fragment));
} else { // rFrag.contentType == Record.ct_handshake
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;
this.nextMessageSeq = hsFrag.messageSeq + 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, hsFrag.recordSeq,
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, hsFrag.recordSeq,
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 != Record.ct_handshake) {
break;
} else {
hmFrag = (HandshakeFragment)rFrag;
}
}
} while (!bufferedFragments.isEmpty() &&
(msgSeq == hmFrag.messageSeq));
// handshake hashing
handshakeHashing(hsFrag, plaintext);
this.nextRecordSeq = maxRecodeSN + 1;
this.nextMessageSeq = msgSeq + 1;
return plaintext;
}
}
}
boolean flightIsReady() {
//
// the ChangeCipherSpec/Finished flight
//
if (expectCCSFlight) {
// Have the ChangeCipherSpec/Finished messages been received?
return hasFinisedMessage(bufferedFragments);
}
if (flightType == (byte)0xFF) {
return false;
}
if ((flightType == HandshakeMessage.ht_client_hello) ||
(flightType == HandshakeMessage.ht_hello_request) ||
(flightType == HandshakeMessage.ht_hello_verify_request)) {
// single handshake message flight
return hasCompleted(holesMap.get(flightType));
}
//
// the ServerHello flight
//
if (flightType == HandshakeMessage.ht_server_hello) {
// Firstly, check the first flight handshake message.
if (!hasCompleted(holesMap.get(flightType))) {
return false;
}
//
// an abbreviated handshake
//
if (isAbbreviatedHandshake) {
// Ready to use the flight if received the
// ChangeCipherSpec and Finished messages.
return hasFinisedMessage(bufferedFragments);
}
//
// a full handshake
//
if (lastHandshakeFragment.handshakeType !=
HandshakeMessage.ht_server_hello_done) {
// Not yet got the final message of the flight.
return false;
}
// Have all handshake message been received?
return hasCompleted(bufferedFragments,
flightTopMessageSeq, lastHandshakeFragment.messageSeq);
}
//
// 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 == HandshakeMessage.ht_certificate) ||
(flightType == HandshakeMessage.ht_client_key_exchange)) {
// Firstly, check the first flight handshake message.
if (!hasCompleted(holesMap.get(flightType))) {
return false;
}
if (!hasFinisedMessage(bufferedFragments)) {
// not yet got the ChangeCipherSpec/Finished messages
return false;
}
if (flightType == HandshakeMessage.ht_client_key_exchange) {
// single handshake message flight
return true;
}
//
// flightType == HandshakeMessage.ht_certificate
//
// We don't support certificates containing fixed
// Diffie-Hellman parameters. Therefore, CertificateVerify
// message is required if client Certificate message presents.
//
if (lastHandshakeFragment.handshakeType !=
HandshakeMessage.ht_certificate_verify) {
// Not yet got the final message of the flight.
return false;
}
// Have all handshake message been received?
return hasCompleted(bufferedFragments,
flightTopMessageSeq, lastHandshakeFragment.messageSeq);
}
//
// Otherwise, need to receive more handshake messages.
//
return false;
}
private boolean isSessionResuming(
byte[] fragment, byte[] prevSid) throws SSLException {
// As the first fragment of ServerHello should be big enough
// to hold the session_id field, need not to worry about the
// fragmentation here.
if ((fragment == null) || (fragment.length < 38)) {
// 38: the minimal ServerHello body length
throw new SSLException(
"Invalid ServerHello message: no sufficient data");
}
int sidLen = fragment[34]; // 34: the length field
if (sidLen > 32) { // opaque SessionID<0..32>
throw new SSLException(
"Invalid ServerHello message: invalid session id");
}
if (fragment.length < 38 + sidLen) {
throw new SSLException(
"Invalid ServerHello message: no sufficient data");
}
if (sidLen != 0 && (prevSid.length == sidLen)) {
// may be a session-resuming handshake
for (int i = 0; i < sidLen; i++) {
if (prevSid[i] != fragment[35 + i]) {
// 35: the session identifier
return false;
}
}
return true;
}
return false;
}
private byte[] getSessionID(byte[] fragment) {
// The validity has been checked in the call to isSessionResuming().
int sidLen = fragment[34]; // 34: the sessionID length field
byte[] temporary = new byte[sidLen];
System.arraycopy(fragment, 35, temporary, 0, sidLen);
return temporary;
}
// 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 hasFinisedMessage(
Set<RecordFragment> fragments) {
boolean hasCCS = false;
boolean hasFin = false;
for (RecordFragment fragment : fragments) {
if (fragment.contentType == Record.ct_change_cipher_spec) {
if (hasFin) {
return true;
}
hasCCS = true;
} else if (fragment.contentType == Record.ct_handshake) {
// Finished is the first expected message of a new epoch.
if (fragment.isCiphertext) {
if (hasCCS) {
return true;
}
hasFin = true;
}
}
}
return hasFin && hasCCS;
}
private boolean hasCompleted(List<HoleDescriptor> holes) {
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 != Record.ct_handshake) ||
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(holesMap.get(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 ((hsType == HandshakeMessage.ht_hello_request) ||
(hsType == HandshakeMessage.ht_hello_verify_request)) {
// omitted from handshake hash computation
return;
}
if ((hsFrag.messageSeq == 0) &&
(hsType == HandshakeMessage.ht_client_hello)) {
// omit initial ClientHello message
//
// 4: handshake header
// 2: ClientHello.client_version
// 32: ClientHello.random
int sidLen = plaintext.fragment.get(38);
if (sidLen == 0) { // empty session_id, initial handshake
return;
}
}
// calculate the DTLS header
byte[] temporary = new byte[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.position(4); // ignore the TLS header
if ((hsType != HandshakeMessage.ht_finished) &&
(hsType != HandshakeMessage.ht_certificate_verify)) {
if (handshakeHash == null) {
// used for cache only
handshakeHash = new HandshakeHash(false);
}
handshakeHash.update(temporary, 0, 12);
handshakeHash.update(plaintext.fragment);
} else {
// Reserve until this handshake message has been processed.
if (handshakeHash == null) {
// used for cache only
handshakeHash = new HandshakeHash(false);
}
handshakeHash.reserve(temporary, 0, 12);
handshakeHash.reserve(plaintext.fragment);
}
plaintext.fragment.position(0); // restore the position
}
}
}