private void finishKex() throws IOException {
if (sessionId == null) sessionId = kxs.H;
establishKeyMaterial();
/* Tell the other side that we start using the new material */
PacketNewKeys ign = new PacketNewKeys();
tm.sendKexMessage(ign.getPayload());
BlockCipher cbc;
MAC mac;
ICompressor comp;
try {
cbc =
BlockCipherFactory.createCipher(
kxs.np.enc_algo_client_to_server,
true,
km.enc_key_client_to_server,
km.initial_iv_client_to_server);
mac = new MAC(kxs.np.mac_algo_client_to_server, km.integrity_key_client_to_server);
comp = CompressionFactory.createCompressor(kxs.np.comp_algo_client_to_server);
} catch (IllegalArgumentException e1) {
throw new IOException("Fatal error during MAC startup!");
}
tm.changeSendCipher(cbc, mac);
tm.changeSendCompression(comp);
tm.kexFinished();
}
public synchronized void initiateKEX(CryptoWishList cwl, DHGexParameters dhgex)
throws IOException {
nextKEXcryptoWishList = cwl;
nextKEXdhgexParameters = dhgex;
if (kxs == null) {
kxs = new KexState();
kxs.dhgexParameters = nextKEXdhgexParameters;
PacketKexInit kp = new PacketKexInit(nextKEXcryptoWishList, rnd);
kxs.localKEX = kp;
tm.sendKexMessage(kp.getPayload());
}
}
public synchronized void handleMessage(byte[] msg, int msglen) throws IOException {
PacketKexInit kip;
if (msg == null) {
synchronized (accessLock) {
connectionClosed = true;
accessLock.notifyAll();
return;
}
}
if ((kxs == null) && (msg[0] != Packets.SSH_MSG_KEXINIT))
throw new IOException("Unexpected KEX message (type " + msg[0] + ")");
if (ignore_next_kex_packet) {
ignore_next_kex_packet = false;
return;
}
if (msg[0] == Packets.SSH_MSG_KEXINIT) {
if ((kxs != null) && (kxs.state != 0))
throw new IOException("Unexpected SSH_MSG_KEXINIT message during on-going kex exchange!");
if (kxs == null) {
/*
* Ah, OK, peer wants to do KEX. Let's be nice and play
* together.
*/
kxs = new KexState();
kxs.dhgexParameters = nextKEXdhgexParameters;
kip = new PacketKexInit(nextKEXcryptoWishList, rnd);
kxs.localKEX = kip;
tm.sendKexMessage(kip.getPayload());
}
kip = new PacketKexInit(msg, 0, msglen);
kxs.remoteKEX = kip;
kxs.np =
mergeKexParameters(kxs.localKEX.getKexParameters(), kxs.remoteKEX.getKexParameters());
if (kxs.np == null) throw new IOException("Cannot negotiate, proposals do not match.");
if (kxs.remoteKEX.isFirst_kex_packet_follows() && (kxs.np.guessOK == false)) {
/*
* Guess was wrong, we need to ignore the next kex packet.
*/
ignore_next_kex_packet = true;
}
if (kxs.np.kex_algo.equals("diffie-hellman-group-exchange-sha1")) {
if (kxs.dhgexParameters.getMin_group_len() == 0
|| csh.server_versioncomment.matches("OpenSSH_2\\.([0-4]\\.|5\\.[0-2]).*")) {
PacketKexDhGexRequestOld dhgexreq = new PacketKexDhGexRequestOld(kxs.dhgexParameters);
tm.sendKexMessage(dhgexreq.getPayload());
} else {
PacketKexDhGexRequest dhgexreq = new PacketKexDhGexRequest(kxs.dhgexParameters);
tm.sendKexMessage(dhgexreq.getPayload());
}
kxs.state = 1;
return;
}
if (kxs.np.kex_algo.equals("diffie-hellman-group1-sha1")
|| kxs.np.kex_algo.equals("diffie-hellman-group14-sha1")) {
kxs.dhx = new DhExchange();
if (kxs.np.kex_algo.equals("diffie-hellman-group1-sha1")) kxs.dhx.init(1, rnd);
else kxs.dhx.init(14, rnd);
PacketKexDHInit kp = new PacketKexDHInit(kxs.dhx.getE());
tm.sendKexMessage(kp.getPayload());
kxs.state = 1;
return;
}
throw new IllegalStateException("Unkown KEX method!");
}
if (msg[0] == Packets.SSH_MSG_NEWKEYS) {
if (km == null)
throw new IOException("Peer sent SSH_MSG_NEWKEYS, but I have no key material ready!");
BlockCipher cbc;
MAC mac;
ICompressor comp;
try {
cbc =
BlockCipherFactory.createCipher(
kxs.np.enc_algo_server_to_client,
false,
km.enc_key_server_to_client,
km.initial_iv_server_to_client);
mac = new MAC(kxs.np.mac_algo_server_to_client, km.integrity_key_server_to_client);
comp = CompressionFactory.createCompressor(kxs.np.comp_algo_server_to_client);
} catch (IllegalArgumentException e1) {
throw new IOException("Fatal error during MAC startup!");
}
tm.changeRecvCipher(cbc, mac);
tm.changeRecvCompression(comp);
ConnectionInfo sci = new ConnectionInfo();
kexCount++;
sci.keyExchangeAlgorithm = kxs.np.kex_algo;
sci.keyExchangeCounter = kexCount;
sci.clientToServerCryptoAlgorithm = kxs.np.enc_algo_client_to_server;
sci.serverToClientCryptoAlgorithm = kxs.np.enc_algo_server_to_client;
sci.clientToServerMACAlgorithm = kxs.np.mac_algo_client_to_server;
sci.serverToClientMACAlgorithm = kxs.np.mac_algo_server_to_client;
sci.serverHostKeyAlgorithm = kxs.np.server_host_key_algo;
sci.serverHostKey = kxs.hostkey;
synchronized (accessLock) {
lastConnInfo = sci;
accessLock.notifyAll();
}
kxs = null;
return;
}
if ((kxs == null) || (kxs.state == 0)) throw new IOException("Unexpected Kex submessage!");
if (kxs.np.kex_algo.equals("diffie-hellman-group-exchange-sha1")) {
if (kxs.state == 1) {
PacketKexDhGexGroup dhgexgrp = new PacketKexDhGexGroup(msg, 0, msglen);
kxs.dhgx = new DhGroupExchange(dhgexgrp.getP(), dhgexgrp.getG());
kxs.dhgx.init(rnd);
PacketKexDhGexInit dhgexinit = new PacketKexDhGexInit(kxs.dhgx.getE());
tm.sendKexMessage(dhgexinit.getPayload());
kxs.state = 2;
return;
}
if (kxs.state == 2) {
PacketKexDhGexReply dhgexrpl = new PacketKexDhGexReply(msg, 0, msglen);
kxs.hostkey = dhgexrpl.getHostKey();
if (verifier != null) {
boolean vres = false;
try {
vres =
verifier.verifyServerHostKey(
hostname, port, kxs.np.server_host_key_algo, kxs.hostkey);
} catch (Exception e) {
throw (IOException)
new IOException("The server hostkey was not accepted by the verifier callback.")
.initCause(e);
}
if (vres == false)
throw new IOException("The server hostkey was not accepted by the verifier callback");
}
kxs.dhgx.setF(dhgexrpl.getF());
try {
kxs.H =
kxs.dhgx.calculateH(
csh.getClientString(),
csh.getServerString(),
kxs.localKEX.getPayload(),
kxs.remoteKEX.getPayload(),
dhgexrpl.getHostKey(),
kxs.dhgexParameters);
} catch (IllegalArgumentException e) {
throw (IOException) new IOException("KEX error.").initCause(e);
}
boolean res = verifySignature(dhgexrpl.getSignature(), kxs.hostkey);
if (res == false) throw new IOException("Hostkey signature sent by remote is wrong!");
kxs.K = kxs.dhgx.getK();
finishKex();
kxs.state = -1;
return;
}
throw new IllegalStateException("Illegal State in KEX Exchange!");
}
if (kxs.np.kex_algo.equals("diffie-hellman-group1-sha1")
|| kxs.np.kex_algo.equals("diffie-hellman-group14-sha1")) {
if (kxs.state == 1) {
PacketKexDHReply dhr = new PacketKexDHReply(msg, 0, msglen);
kxs.hostkey = dhr.getHostKey();
if (verifier != null) {
boolean vres = false;
try {
vres =
verifier.verifyServerHostKey(
hostname, port, kxs.np.server_host_key_algo, kxs.hostkey);
} catch (Exception e) {
throw (IOException)
new IOException("The server hostkey was not accepted by the verifier callback.")
.initCause(e);
}
if (vres == false)
throw new IOException("The server hostkey was not accepted by the verifier callback");
}
kxs.dhx.setF(dhr.getF());
try {
kxs.H =
kxs.dhx.calculateH(
csh.getClientString(),
csh.getServerString(),
kxs.localKEX.getPayload(),
kxs.remoteKEX.getPayload(),
dhr.getHostKey());
} catch (IllegalArgumentException e) {
throw (IOException) new IOException("KEX error.").initCause(e);
}
boolean res = verifySignature(dhr.getSignature(), kxs.hostkey);
if (res == false) throw new IOException("Hostkey signature sent by remote is wrong!");
kxs.K = kxs.dhx.getK();
finishKex();
kxs.state = -1;
return;
}
}
throw new IllegalStateException("Unkown KEX method! (" + kxs.np.kex_algo + ")");
}