/*
* Copyright (c) 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 94065 USA
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package sun.security.ssl;
import java.io.IOException;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.security.GeneralSecurityException;
import java.security.ProviderException;
import java.security.SecureRandom;
import java.text.MessageFormat;
import java.util.Locale;
import java.util.Optional;
import javax.crypto.SecretKey;
import javax.net.ssl.SSLHandshakeException;
import sun.security.ssl.PskKeyExchangeModesExtension.PskKeyExchangeModesSpec;
import sun.security.ssl.SSLHandshake.HandshakeMessage;
/**
* Pack of the NewSessionTicket handshake message.
*/
final class NewSessionTicket {
private static final int MAX_TICKET_LIFETIME = 604800; // seconds, 7 days
static final SSLConsumer handshakeConsumer =
new NewSessionTicketConsumer();
static final SSLProducer kickstartProducer =
new NewSessionTicketKickstartProducer();
static final HandshakeProducer handshakeProducer =
new NewSessionTicketProducer();
/**
* The NewSessionTicketMessage handshake message.
*/
static final class NewSessionTicketMessage extends HandshakeMessage {
final int ticketLifetime;
final int ticketAgeAdd;
final byte[] ticketNonce;
final byte[] ticket;
final SSLExtensions extensions;
NewSessionTicketMessage(HandshakeContext context,
int ticketLifetime, SecureRandom generator,
byte[] ticketNonce, byte[] ticket) {
super(context);
this.ticketLifetime = ticketLifetime;
this.ticketAgeAdd = generator.nextInt();
this.ticketNonce = ticketNonce;
this.ticket = ticket;
this.extensions = new SSLExtensions(this);
}
NewSessionTicketMessage(HandshakeContext context,
ByteBuffer m) throws IOException {
super(context);
// struct {
// uint32 ticket_lifetime;
// uint32 ticket_age_add;
// opaque ticket_nonce<0..255>;
// opaque ticket<1..2^16-1>;
// Extension extensions<0..2^16-2>;
// } NewSessionTicket;
if (m.remaining() < 14) {
context.conContext.fatal(Alert.ILLEGAL_PARAMETER,
"Invalid NewSessionTicket message: no sufficient data");
}
this.ticketLifetime = Record.getInt32(m);
this.ticketAgeAdd = Record.getInt32(m);
this.ticketNonce = Record.getBytes8(m);
if (m.remaining() < 5) {
context.conContext.fatal(Alert.ILLEGAL_PARAMETER,
"Invalid NewSessionTicket message: no sufficient data");
}
this.ticket = Record.getBytes16(m);
if (ticket.length == 0) {
context.conContext.fatal(Alert.ILLEGAL_PARAMETER,
"No ticket in the NewSessionTicket handshake message");
}
if (m.remaining() < 2) {
context.conContext.fatal(Alert.ILLEGAL_PARAMETER,
"Invalid NewSessionTicket message: no sufficient data");
}
SSLExtension[] supportedExtensions =
context.sslConfig.getEnabledExtensions(
SSLHandshake.NEW_SESSION_TICKET);
this.extensions = new SSLExtensions(this, m, supportedExtensions);
}
@Override
public SSLHandshake handshakeType() {
return SSLHandshake.NEW_SESSION_TICKET;
}
@Override
public int messageLength() {
int extLen = extensions.length();
if (extLen == 0) {
extLen = 2; // empty extensions
}
return 8 + ticketNonce.length + 1 +
ticket.length + 2 + extLen;
}
@Override
public void send(HandshakeOutStream hos) throws IOException {
hos.putInt32(ticketLifetime);
hos.putInt32(ticketAgeAdd);
hos.putBytes8(ticketNonce);
hos.putBytes16(ticket);
// Is it an empty extensions?
if (extensions.length() == 0) {
hos.putInt16(0);
} else {
extensions.send(hos);
}
}
@Override
public String toString() {
MessageFormat messageFormat = new MessageFormat(
"\"NewSessionTicket\": '{'\n" +
" \"ticket_lifetime\" : \"{0}\",\n" +
" \"ticket_age_add\" : \"{1}\",\n" +
" \"ticket_nonce\" : \"{2}\",\n" +
" \"ticket\" : \"{3}\",\n" +
" \"extensions\" : [\n" +
"{4}\n" +
" ]\n" +
"'}'",
Locale.ENGLISH);
Object[] messageFields = {
ticketLifetime,
"<omitted>", //ticketAgeAdd should not be logged
Utilities.toHexString(ticketNonce),
Utilities.toHexString(ticket),
Utilities.indent(extensions.toString(), " ")
};
return messageFormat.format(messageFields);
}
}
private static SecretKey derivePreSharedKey(CipherSuite.HashAlg hashAlg,
SecretKey resumptionMasterSecret, byte[] nonce) throws IOException {
try {
HKDF hkdf = new HKDF(hashAlg.name);
byte[] hkdfInfo = SSLSecretDerivation.createHkdfInfo(
"tls13 resumption".getBytes(), nonce, hashAlg.hashLength);
return hkdf.expand(resumptionMasterSecret, hkdfInfo,
hashAlg.hashLength, "TlsPreSharedKey");
} catch (GeneralSecurityException gse) {
throw (SSLHandshakeException) new SSLHandshakeException(
"Could not derive PSK").initCause(gse);
}
}
private static final
class NewSessionTicketKickstartProducer implements SSLProducer {
// Prevent instantiation of this class.
private NewSessionTicketKickstartProducer() {
// blank
}
@Override
public byte[] produce(ConnectionContext context) throws IOException {
// The producing happens in server side only.
ServerHandshakeContext shc = (ServerHandshakeContext)context;
// Is this session resumable?
if (!shc.handshakeSession.isRejoinable()) {
return null;
}
// What's the requested PSK key exchange modes?
//
// Note that currently, the NewSessionTicket post-handshake is
// produced and delivered only in the current handshake context
// if required.
PskKeyExchangeModesSpec pkemSpec =
(PskKeyExchangeModesSpec)shc.handshakeExtensions.get(
SSLExtension.PSK_KEY_EXCHANGE_MODES);
if (pkemSpec == null || !pkemSpec.contains(
PskKeyExchangeModesExtension.PskKeyExchangeMode.PSK_DHE_KE)) {
// Client doesn't support PSK with (EC)DHE key establishment.
return null;
}
// get a new session ID
SSLSessionContextImpl sessionCache = (SSLSessionContextImpl)
shc.sslContext.engineGetServerSessionContext();
SessionId newId = new SessionId(true,
shc.sslContext.getSecureRandom());
Optional<SecretKey> resumptionMasterSecret =
shc.handshakeSession.getResumptionMasterSecret();
if (!resumptionMasterSecret.isPresent()) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
SSLLogger.fine(
"Session has no resumption secret. No ticket sent.");
}
return null;
}
// construct the PSK and handshake message
BigInteger nonce = shc.handshakeSession.incrTicketNonceCounter();
byte[] nonceArr = nonce.toByteArray();
SecretKey psk = derivePreSharedKey(
shc.negotiatedCipherSuite.hashAlg,
resumptionMasterSecret.get(), nonceArr);
int sessionTimeoutSeconds = sessionCache.getSessionTimeout();
if (sessionTimeoutSeconds > MAX_TICKET_LIFETIME) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
SSLLogger.fine(
"Session timeout is too long. No ticket sent.");
}
return null;
}
NewSessionTicketMessage nstm = new NewSessionTicketMessage(shc,
sessionTimeoutSeconds, shc.sslContext.getSecureRandom(),
nonceArr, newId.getId());
if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
SSLLogger.fine(
"Produced NewSessionTicket handshake message", nstm);
}
// create and cache the new session
// The new session must be a child of the existing session so
// they will be invalidated together, etc.
SSLSessionImpl sessionCopy = new SSLSessionImpl(shc,
shc.handshakeSession.getSuite(), newId,
shc.handshakeSession.getCreationTime());
shc.handshakeSession.addChild(sessionCopy);
sessionCopy.setPreSharedKey(psk);
sessionCopy.setPskIdentity(newId.getId());
sessionCopy.setTicketAgeAdd(nstm.ticketAgeAdd);
sessionCache.put(sessionCopy);
// Output the handshake message.
nstm.write(shc.handshakeOutput);
shc.handshakeOutput.flush();
// The message has been delivered.
return null;
}
}
/**
* The "NewSessionTicket" handshake message producer.
*/
private static final class NewSessionTicketProducer
implements HandshakeProducer {
// Prevent instantiation of this class.
private NewSessionTicketProducer() {
// blank
}
@Override
public byte[] produce(ConnectionContext context,
HandshakeMessage message) throws IOException {
// NSTM may be sent in response to handshake messages.
// For example: key update
throw new ProviderException(
"NewSessionTicket handshake producer not implemented");
}
}
private static final
class NewSessionTicketConsumer implements SSLConsumer {
// Prevent instantiation of this class.
private NewSessionTicketConsumer() {
// blank
}
@Override
public void consume(ConnectionContext context,
ByteBuffer message) throws IOException {
// Note: Although the resumption master secret depends on the
// client's second flight, servers which do not request client
// authentication MAY compute the remainder of the transcript
// independently and then send a NewSessionTicket immediately
// upon sending its Finished rather than waiting for the client
// Finished.
//
// The consuming happens in client side only. As the server
// may send the NewSessionTicket before handshake complete, the
// context may be a PostHandshakeContext or HandshakeContext
// instance.
HandshakeContext hc = (HandshakeContext)context;
NewSessionTicketMessage nstm =
new NewSessionTicketMessage(hc, message);
if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
SSLLogger.fine(
"Consuming NewSessionTicket message", nstm);
}
// discard tickets with timeout 0
if (nstm.ticketLifetime <= 0 ||
nstm.ticketLifetime > MAX_TICKET_LIFETIME) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
SSLLogger.fine(
"Discarding NewSessionTicket with lifetime "
+ nstm.ticketLifetime, nstm);
}
return;
}
SSLSessionContextImpl sessionCache = (SSLSessionContextImpl)
hc.sslContext.engineGetClientSessionContext();
if (sessionCache.getSessionTimeout() > MAX_TICKET_LIFETIME) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
SSLLogger.fine(
"Session cache lifetime is too long. Discarding ticket.");
}
return;
}
SSLSessionImpl sessionToSave = hc.conContext.conSession;
Optional<SecretKey> resumptionMasterSecret =
sessionToSave.getResumptionMasterSecret();
if (!resumptionMasterSecret.isPresent()) {
if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
SSLLogger.fine(
"Session has no resumption master secret. Ignoring ticket.");
}
return;
}
// derive the PSK
SecretKey psk = derivePreSharedKey(
sessionToSave.getSuite().hashAlg, resumptionMasterSecret.get(),
nstm.ticketNonce);
// create and cache the new session
// The new session must be a child of the existing session so
// they will be invalidated together, etc.
SessionId newId =
new SessionId(true, hc.sslContext.getSecureRandom());
SSLSessionImpl sessionCopy =
new SSLSessionImpl(hc, sessionToSave.getSuite(), newId,
sessionToSave.getCreationTime());
sessionToSave.addChild(sessionCopy);
sessionCopy.setPreSharedKey(psk);
sessionCopy.setTicketAgeAdd(nstm.ticketAgeAdd);
sessionCopy.setPskIdentity(nstm.ticket);
sessionCache.put(sessionCopy);
// clean handshake context
hc.conContext.finishPostHandshake();
}
}
}