private void receive_newkeys(Buffer buf, KeyExchange kex)
{
updateKeys(kex);
in_kex = false;
}
private void updateKeys(KeyExchange kex)
{
byte[] K = kex.getK();
byte[] H = kex.getH();
HASH hash = kex.getHash();
// string[] guess=kex.guess;
if (session_id == null)
{
session_id = new byte[H.Length];
Array.Copy(H, 0, session_id, 0, H.Length);
}
/*
Initial IV client to server: HASH (K || H || "A" || session_id)
Initial IV server to client: HASH (K || H || "B" || session_id)
Encryption key client to server: HASH (K || H || "C" || session_id)
Encryption key server to client: HASH (K || H || "D" || session_id)
Integrity key client to server: HASH (K || H || "E" || session_id)
Integrity key server to client: HASH (K || H || "F" || session_id)
*/
buf.reset();
buf.putMPInt(K);
buf.putByte(H);
buf.putByte((byte)0x41);
buf.putByte(session_id);
hash.update(buf.buffer, 0, buf.index);
IVc2s = hash.digest();
int j = buf.index - session_id.Length - 1;
buf.buffer[j]++;
hash.update(buf.buffer, 0, buf.index);
IVs2c = hash.digest();
buf.buffer[j]++;
hash.update(buf.buffer, 0, buf.index);
Ec2s = hash.digest();
buf.buffer[j]++;
hash.update(buf.buffer, 0, buf.index);
Es2c = hash.digest();
buf.buffer[j]++;
hash.update(buf.buffer, 0, buf.index);
MACc2s = hash.digest();
buf.buffer[j]++;
hash.update(buf.buffer, 0, buf.index);
MACs2c = hash.digest();
try
{
Type c;
string method;
method = guess[KeyExchange.PROPOSAL_ENC_ALGS_STOC];
c = Type.GetType(getConfig(method));
s2ccipher = (Cipher)(c.newInstance());
while (s2ccipher.getBlockSize() > Es2c.Length)
{
buf.reset();
buf.putMPInt(K);
buf.putByte(H);
buf.putByte(Es2c);
hash.update(buf.buffer, 0, buf.index);
byte[] foo = hash.digest();
byte[] bar = new byte[Es2c.Length + foo.Length];
Array.Copy(Es2c, 0, bar, 0, Es2c.Length);
Array.Copy(foo, 0, bar, Es2c.Length, foo.Length);
Es2c = bar;
}
s2ccipher.init(Cipher.DECRYPT_MODE, Es2c, IVs2c);
s2ccipher_size = s2ccipher.getIVSize();
method = guess[KeyExchange.PROPOSAL_MAC_ALGS_STOC];
c = Type.GetType(getConfig(method));
s2cmac = (MAC)(c.newInstance());
s2cmac.init(MACs2c);
//mac_buf=new byte[s2cmac.getBlockSize()];
s2cmac_result1 = new byte[s2cmac.getBlockSize()];
s2cmac_result2 = new byte[s2cmac.getBlockSize()];
method = guess[KeyExchange.PROPOSAL_ENC_ALGS_CTOS];
c = Type.GetType(getConfig(method));
c2scipher = (Cipher)(c.newInstance());
while (c2scipher.getBlockSize() > Ec2s.Length)
{
buf.reset();
buf.putMPInt(K);
buf.putByte(H);
buf.putByte(Ec2s);
hash.update(buf.buffer, 0, buf.index);
byte[] foo = hash.digest();
byte[] bar = new byte[Ec2s.Length + foo.Length];
Array.Copy(Ec2s, 0, bar, 0, Ec2s.Length);
Array.Copy(foo, 0, bar, Ec2s.Length, foo.Length);
Ec2s = bar;
}
c2scipher.init(Cipher.ENCRYPT_MODE, Ec2s, IVc2s);
c2scipher_size = c2scipher.getIVSize();
method = guess[KeyExchange.PROPOSAL_MAC_ALGS_CTOS];
c = Type.GetType(getConfig(method));
c2smac = (MAC)(c.newInstance());
c2smac.init(MACc2s);
method = guess[KeyExchange.PROPOSAL_COMP_ALGS_CTOS];
initDeflater(method);
method = guess[KeyExchange.PROPOSAL_COMP_ALGS_STOC];
initInflater(method);
}
catch (Exception e)
{
if (e is JSchException)
throw e;
throw new JSchException(e.ToString(), e);
//Console.Error.WriteLine("updatekeys: "+e);
}
}
private void checkHost(string chost, int port, KeyExchange kex)
{
string shkc = getConfig("StrictHostKeyChecking");
if (hostKeyAlias != null)
{
chost = hostKeyAlias;
}
//Console.Error.WriteLine("shkc: "+shkc);
byte[] K_S = kex.getHostKey();
string key_type = kex.getKeyType();
string key_fprint = kex.getFingerPrint();
if (hostKeyAlias == null && port != 22)
{
chost = ("[" + chost + "]:" + port);
}
// hostkey=new HostKey(chost, K_S);
HostKeyRepository hkr = jsch.getHostKeyRepository();
int i = 0;
lock (hkr)
{
i = hkr.check(chost, K_S);
}
bool insert = false;
if ((shkc.Equals("ask") || shkc.Equals("yes")) &&
i == HostKeyRepository.CHANGED)
{
string file = null;
lock (hkr)
{
file = hkr.getKnownHostsRepositoryID();
}
if (file == null) { file = "known_hosts"; }
bool b = false;
if (userinfo != null)
{
string message =
"WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!\n" +
"IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!\n" +
"Someone could be eavesdropping on you right now (man-in-the-middle attack)!\n" +
"It is also possible that the " + key_type + " host key has just been changed.\n" +
"The fingerprint for the " + key_type + " key sent by the remote host is\n" +
key_fprint + ".\n" +
"Please contact your system administrator.\n" +
"Add correct host key in " + file + " to get rid of this message.";
if (shkc.Equals("ask"))
{
b = userinfo.promptYesNo(message +
"\nDo you want to delete the old key and insert the new key?");
}
else
{ // shkc.Equals("yes")
userinfo.showMessage(message);
}
}
if (!b)
{
throw new JSchException("HostKey has been changed: " + chost);
}
lock (hkr)
{
hkr.remove(chost,
(key_type.Equals("DSA") ? "ssh-dss" : "ssh-rsa"),
null);
insert = true;
}
}
if ((shkc.Equals("ask") || shkc.Equals("yes")) &&
(i != HostKeyRepository.OK) && !insert)
{
if (shkc.Equals("yes"))
{
throw new JSchException("reject HostKey: " + host);
}
//Console.Error.WriteLine("finger-print: "+key_fprint);
if (userinfo != null)
{
bool foo = userinfo.promptYesNo(
"The authenticity of host '" + host + "' can't be established.\n" +
key_type + " key fingerprint is " + key_fprint + ".\n" +
"Are you sure you want to continue connecting?"
);
if (!foo)
{
throw new JSchException("reject HostKey: " + host);
}
insert = true;
}
else
{
if (i == HostKeyRepository.NOT_INCLUDED)
throw new JSchException("UnknownHostKey: " + host + ". " + key_type + " key fingerprint is " + key_fprint);
else
throw new JSchException("HostKey has been changed: " + host);
}
}
if (shkc.Equals("no") &&
HostKeyRepository.NOT_INCLUDED == i)
{
insert = true;
}
if (i == HostKeyRepository.OK &&
JSch.getLogger().isEnabled(Logger.INFO))
{
JSch.getLogger().log(Logger.INFO,
"Host '" + host + "' is known and mathces the " + key_type + " host key");
}
if (insert &&
JSch.getLogger().isEnabled(Logger.WARN))
{
JSch.getLogger().log(Logger.WARN,
"Permanently added '" + host + "' (" + key_type + ") to the list of known hosts.");
}
string hkh = getConfig("HashKnownHosts");
if (hkh.Equals("yes") && (hkr is KnownHosts))
{
hostkey = ((KnownHosts)hkr).createHashedHostKey(chost, K_S);
}
else
{
hostkey = new HostKey(chost, K_S);
}
if (insert)
{
lock (hkr)
{
hkr.add(hostkey, userinfo);
}
}
}
