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SSH Tunneling into a Web Server

“From a PC running Windows 7 or Linux I would like to connect to a linux server so I can view the web pages generated for a web application hidden behind a firewall.”

If this sounds like something you need to do then read on.

What we are going to do is implement SSH tunneling. SSH is used to ‘tunnel’ through the firewall. We then redirect port 80 on the web server through the SSH tunnel to port 1066 on the local machine.

You will need to have SSH login details to access your webserver.

On Windows

You will need to have Putty installed on your PC.

Start Putty.

Enter your SSH login URL as the host name, and if no alternative port has been specified for SSH, 22 as the host port.

In the left hand column go to Connection -> SSH -> Tunnels.

In the source port type 1066.

In the destination you will typically type ‘localhost:80′. However this may change if the web application you are accessing runs on a different port (e.g. Tomcat applications usually run on port 8080, and your own application may be something different), so you may have to type localhost:8080 to access Tomcat without going through the main webserver. In addition the localhost part of this may change if the webpages you are trying to access are on a different machine to the one you are trying to SSH into (e.g. you may have to type node2:80 if the machine you are logging into is connected to node2 as the machine you are running the web application on).

Click Add.

In the left hand column click ‘Session’ at the top.

Click ‘Save’ to save these settings.

Click Open.

You will be prompted for your username and password. (This opens a shell on your target machine so you can run linux command lines here).

To view the web application visit the following URL in your browser. http://localhost:1066/

On Linux

This can be done by opening a terminal window and typing in:

ssh -L 1066:localhost:80 username@websiteURL

In your webbrowser then going to http://localhost:1066 will give you the tracking system front end.

GregorianCalendar calStart = new GregorianCalendar() ;
 calStart.set( Calendar.HOUR_OF_DAY, 18 ) ;
 calStart.set( Calendar.MINUTE, 1 ) ;
 String sql = "SELECT * FROM " + dbh.userTable.tableName +
          " WHERE status=1 AND "
          + SQLStrings.getWhereBetweenDates( "signup_time", calStart ) ;

.....

public static String getWhereBetweenDates( String columnName, GregorianCalendar calStart)
{
    GregorianCalendar now = new GregorianCalendar() ;
    StringBuffer sb = new StringBuffer( columnName + " BETWEEN " ) ;
    SimpleDateFormat df = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" ) ;
    String beforeDateString = df.format( calStart.getTime() ) ;
    String afterDateString = df.format( now.getTime() ) ;
    sb.append( beforeDateString + " AND " + afterDateString ) ;
    return sb.toString() ;
}