Tamir.SharpSsh.jsch.Session.checkHost C# (CSharp) Method

		private void checkHost(String host, KeyExchange kex)  
		{
			String shkc=getConfig("StrictHostKeyChecking");

			//System.Console.WriteLine("shkc: "+shkc);

			byte[] K_S=kex.getHostKey();
			String key_type=kex.getKeyType();
			String key_fprint=kex.getFingerPrint();

			hostkey=new HostKey(host, K_S);

			HostKeyRepository hkr=jsch.getHostKeyRepository();
			int i=0;
			lock(hkr)
			{
				i=hkr.check(host, K_S);
			}

			bool insert=false;

			if((shkc == ("ask") || shkc == ("yes")) &&
				i==HostKeyRepository.CHANGED)
			{
				String file=null;
				lock(hkr)
				{
					file=hkr.getKnownHostsRepositoryID();
				}
				if(file==null){file="known_hosts";}
				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.";

				bool b=false;

				if(userinfo!=null)
				{
					//userinfo.showMessage(message);
					b=userinfo.promptYesNo(message+
						"\nDo you want to delete the old key and insert the new key?");
				}
				//throw new JSchException("HostKey has been changed: "+host);
				if(!b)
				{
					throw new JSchException("HostKey has been changed: "+host);
				}
				else
				{
					lock(hkr)
					{
						hkr.remove(host, 
								  (key_type == ("DSA") ? "ssh-dss" : "ssh-rsa"), 
								   null);
						insert=true;
					}
				}
			}

			//    bool insert=false;

			if((shkc == ("ask") || shkc == ("yes")) &&
				(i!=HostKeyRepository.OK) && !insert)
			{
				if(shkc == ("yes"))
				{
					throw new JSchException("reject HostKey: "+host);
				}
				//System.Console.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 == "no" && HostKeyRepository.NOT_INCLUDED==i)
            {
				insert=true;
			}

			if (insert)
			{
				lock (hkr)
				{
					hkr.add(host, K_S, userinfo);
				}
			}

		}