Managed File Transfer and Security Solutions

Remotely executing server commands using rsh in Java

Overview 

       This article will demonstrate how to execute commands on a server using rsh service using Secure iNet Factory.

Code Example

      Download RSHEx.java

               

01 import com.jscape.inet.bsd.*; 02 import java.io.*; 03 04 public class RSHEx extends BsdAdapter 05 { 06  public void connected(BsdConnectedEvent event) 07  { 08  System.out.println("Connected to host: " + event.getHostname()); 09  } 10 11  public void disconnected(BsdDisconnectedEvent event) 12  { 13  System.out.println("Disconnected from host: " + event.getHostname()); 14  }     15   16  public static void main(String[] args) 17  { 18  Rsh rsh = new Rsh("remote.host.com", "johndoe", "johndoe","ls -la", false); 19  rsh.addBsdListener(new RSHEx()); 20  try 21  { 22  // establish connection 23  rsh.connect(); 24  // issue an rsh command 25  String cmd = "someRSHCommand"; 26  rsh.setCommand(cmd); 27  // execute command 28  rsh.execute(); 29  // get input stream 30  InputStream input = rsh.getInputStream(); 31  // read first byte to determine success or failure 32  int in = input.read(); 33  StringBuffer buffer = new StringBuffer(); 34  if(in == 0) buffer.append("Success! Remote host returned: \n"); 35  else        buffer.append("Failure! Remote host returned: \n"); 36  // read response        37  while((in = input.read()) != -1) buffer.append((char)in); 38  System.out.println(buffer.toString()); 39  } 40  catch(Exception e) 41  { 42  System.out.println(e); 43  } 44  } 45 } 46 Lines 1-2  : Necessary import statments. Lines 6-14 : Events from BsdAdapter Line 18    : Create an Rsh instance Line 19    : Add listener to this Rsh instance so this instance can              receive events from BsdAdapter Lines 25-28 : Set a rsh command and execute it Lines 30-38 : Read response and print it out to the console.

Remotely executing commands on a server using rexec service

Overview 

       This article will demonstrate how to execute commands on a server using rexec service using Secure iNet Factory.

Code Example

       Download RexecEx.java

               

01 import com.jscape.inet.bsd.*; 02 03 public class RexecEx extends BsdAdapter 04 { 05  public void connected(BsdConnectedEvent event) 06  { 07  System.out.println("Connected to host: " + event.getHostname()); 08  } 09 10  public void disconnected(BsdDisconnectedEvent event) 11  { 12  System.out.println("Disconnected from host: " + event.getHostname()); 13  }    14 15  public static void main(String[] args) 16  { 17  try 18  { 19  Rexec rexec = new Rexec("server.com", "jsmith", "secret", "ls -al", false); 20  // add listener 21  rexec.addBsdListener(new RexecEx());        22  // establish connection 23  rexec.connect(); 24  // executes ls -al command on server.com authenticating as user jsmith 25  rexec.execute(); 26  // disconnect 27  rexec.disconnect(); 28 29  } 30  catch (Exception e) 31  { 32  e.printStackTrace(); 33  } 34  } 35 } Line 1       : Necessary import. Lines 5-13 : Methods to handle events from BsdAdapter. Line 19     : Create new Rexec instance.        Line 21     : Add listener to Rexec instance so the Rexec instance can receive events. Line 23     : Connect to the remote server. Line 25     : Execute the command. Line 27     : Disconnect from the remote server.

Communicating with a POP3 server over SSL/TLS in Java

Overview 

       This article will demonstrate how to communicate with a POP3 server over SSL using Secure iNet Factory.

Code Example

      Download POPSSLEx.java

           

01 import java.util.Enumeration; 02 import com.jscape.inet.email.EmailMessage; 03 import com.jscape.inet.popssl.PopSsl; 04 05 06 public class POPSSLEx 07 { 08  public static void ImplicitSSL_TLS() 09  { 10  try 11  { 12  String hostname = "host"; 13  String username = "username"; 14  String password = "password"; 15  // create new PopSsl instance 16  PopSsl ssl = new PopSsl(hostname,995,username,password); 17  // establish SSL/TLS connection 18  ssl.connect(); 19  // get messages and print subject 20  Enumeration e = ssl.getMessages(); 21  while(e.hasMoreElements()) 22  { 23  EmailMessage msg = (EmailMessage)e.nextElement(); 24  System.out.println("Subject: " + msg.getSubject()); 25  } 26  // disconnect 27  ssl.disconnect();  28  } 29  catch (Exception e) 30  { 31  e.printStackTrace(); 32  } 33  } 34   35  public static void ExplicitSSL_TLS() 36  { 37  try 38  { 39  String hostname = "host"; 40  String username = "username"; 41  String password = "password"; 42  // create new PopSsl instance 43  PopSsl ssl = new PopSsl(hostname,110,username,password); 44  // set connection type 45  ssl.setConnectionType(PopSsl.STARTTLS); 46  // establish SSL/TLS connection 47  ssl.connect(); 48  // get messages and print subject 49  Enumeration e = ssl.getMessages(); 50  while(e.hasMoreElements()) 51  { 52  EmailMessage msg = (EmailMessage)e.nextElement(); 53  System.out.println("Subject: " + msg.getSubject()); 54  } 55  // disconnect 56  ssl.disconnect();                         57  } 58  catch (Exception e) 59  { 60  e.printStackTrace(); 61  } 62  } 63   64  public static void main(String[] args) 65  { 66  ImplicitSSL_TLS(); 67  ExplicitSSL_TLS(); 68  } 69 } Lines 1-3  :  Necessary Import Statements. Lines 8-33 :  Connect to POP3 server over SSL on port 995. Lines 35-62 : Connect to POP3 server over SSL on port 110. This function               demonstrates connecting using explicit SSL and STLS command.

Communicating with a POP3 server over SSH in Java

Overview 

       This article will demonstrate how to communicate with a POP3 server over SSH using Secure iNet Factory.

Code Example

       Download POPSSHEx.java

               

01 import java.util.Enumeration; 02 import com.jscape.inet.email.EmailMessage; 03 import com.jscape.inet.popssh.PopSsh; 04 import com.jscape.inet.ssh.util.SshParameters; 05 06 07 public class POPSSHEx 08 { 09  public static void main(String[] args) 10  { 11  try 12  { 13  // connection parameters for SSH server 14  String sshHostname = "pop3.myserver.com"; 15  String sshUsername = "jsmith"; 16  String sshPassword = "secret"; 17 18  // create new SshParameters instance 19  SshParameters sshParams = new SshParameters(sshHostname,sshUsername,sshPassword); 20  // new instance with SSH parameters, hostname, username and password 21  PopSsh pop = new PopSsh(sshParams, "pop3.myserver.com","jsmith","secret"); 22 23   24  pop.connect(); 25  // get messages 26  Enumeration e = pop.getMessages(); 27  while(e.hasMoreElements()) 28  { 29  EmailMessage em = (EmailMessage)e.nextElement(); 30  } 31  // disconnect 32  pop.disconnect(); 33  } 34  catch (Exception e) 35  { 36  e.printStackTrace(); 37  } 38  } 39 } Lines 1-4 : Necessary import statements. Line 19   : Create a new SshParameters instance. Line 21   : Create a new PopSsh instance. Line 24   : Connect to the remote server. Lines 26-30 : Get messages from the server. Each message is of type EmailMessage. Line 32 : Disconnect from the server. Go here for a detailed article on POP protocol.

Communicating with POP3 servers in Java

Overview 

       This article will demonstrate how to communicate with a POP3 server using Secure iNet Factory.

Code Example

       Download POPEx.java

               

01 import com.jscape.inet.email.EmailMessage; 02 import com.jscape.inet.pop.*; 03 import java.util.*; 04 05 public class POPEx extends PopAdapter 06 { 07  Pop pop = null; 08   09  public POPEx(String server, 10  String username, 11  String password, 12  boolean setApopAuthMode) throws PopException 13  { 14  // create new Pop instance 15  pop = new Pop(server, username, password); 16  // set authentication mode to use APOP 17  if (setApopAuthMode) pop.setAuthMode(Pop.AUTH_APOP); 18  // mark messages retrieved for deletion upon logout 19  pop.setDelete(true); 20  } 21   22  public void openConnection() throws PopException 23  { 24  pop.connect(); 25  } 26   27  public void closeConnection() throws PopException 28  { 29  pop.disconnect(); 30  } 31   32  public void connected(PopConnectedEvent event) 33  { 34  System.out.println("Connected to host: " + event.getHostname()); 35  } 36 37  public void disconnected(PopDisconnectedEvent event) 38  { 39  System.out.println("Disconnected from host: " + event.getHostname()); 40  } 41   42  public void commandSent(PopCommandEvent event) 43  { 44  System.out.println("Command : " + event.getCommand()); 45  } 46 47  public void responseReceived(PopResponseEvent event) 48  { 49  System.out.println("Response : " + event.getResponse()); 50  } 51   52  public int getMessageCount() throws PopException 53  { 54  return pop.getMessageCount(); 55  } 56   57  public Enumeration getMessages() throws PopException 58  { 59  return pop.getMessages(); 60  } 61   62  public EmailMessage getMessage(int id) throws PopException 63  { 64  return pop.getMessage(id); 65  } 66   67  public void deleteMessage(int id) throws PopException 68  { 69  pop.deleteMessage(id); 70  } 71   72  public String issueCommand(String cmd) throws PopException 73  { 74  return pop.issueCommand("TOP 1 11"); 75  } 76   77  public static void main(String[] args) 78  { 79  try 80  { 81  POPEx pe = new POPEx("pop.myserver.com","jsmith","secret", true); 82  pe.openConnection(); 83  int count = pe.getMessageCount(); 84  // each message is of type EmailMessage 85  Enumeration messages = pe.getMessages(); 86  // get message with a particular id 87  EmailMessage message = pe.getMessage(0); 88  // delete message with a particular id 89  pe.deleteMessage(0); 90  pe.closeConnection(); 91  } 92  catch (Exception e) 93  { 94  e.printStackTrace(); 95  } 96  } 97 } Lines 1-3  : Necessary import statements. Lines 9-20 : Create a new Pop instance. Lines 22-30 : Methods for opening and closing connection to the POP3 server. Lines 27-50 : Event handlers from PopAdapter. Lines 52-55 : Get message count. Lines 57-60 : Get messages from the server. Lines 62-65 : Get message by id. Lines 67-70 : Delete message by id. Lines 72-75 : Issue a command to the remote server. Go here for a detailed article on POP protocol.

Communication with NNTP servers in Java

Overview 

       This article will demonstrate how to communicate with an NNTP server using Secure iNet Factory.

Code Example

Download NNTPEx.java

               

001 import java.util.*; 002 003 import com.jscape.inet.mime.MimeHeader; 004 import com.jscape.inet.nntp.*; 005 006 public class NNTPEx extends NntpAdapter 007 { 008  Nntp nntp = null; 009   010  public NNTPEx(String server, 011  int timeout, 012  boolean useProxy, 013  String proxyHost, 014  int proxyPort) throws NntpException 015  { 016   017  nntp = new Nntp(server); 018  nntp.setTimeout(timeout); 019  if (useProxy) 020  { 021  nntp.setProxyHost(proxyHost); 022  nntp.setPort(proxyPort); 023  } 024  nntp.addNntpListener(this); 025  } 026   027  public void issueCommand(String cmd) throws NntpException 028  { 029  nntp.issueCommand(cmd); 030  } 031   032  public void openConnection() throws NntpException 033  { 034  nntp.connect(); 035  } 036   037  public void closeConnection() throws NntpException 038  { 039  nntp.disconnect(); 040  } 041   042  public void connected(NntpConnectedEvent event) 043  { 044  System.out.println("Connected to host: " + event.getHostname()); 045  } 046 047  public void disconnected(NntpDisconnectedEvent event) 048  { 049  System.out.println("Disconnected from host: " + event.getHostname()); 050  }    051   052  public Enumeration getNewsGroups() throws NntpException 053  { 054  return nntp.getNewsgroups(); 055  } 056   057  public void setCurrentNewsGroup(String str) throws NntpException 058  { 059  nntp.setNewsgroup(str); 060  } 061   062  public NntpNewsgroup getCurrentNewsGroup() 063  { 064  return nntp.getCurrentNewsgroup(); 065  } 066   067  public Enumeration getArticleHeaders() throws NntpException 068  { 069    070  return nntp.getArticleHeaders();                      071  } 072   073  public NntpArticle getArticle(int id) throws NntpException 074  { 075  return nntp.getArticle(id); 076  } 077   078  public void postArticle(NntpArticle article) throws NntpException 079  { 080  nntp.postArticle(article); 081  } 082   083  public static void main(String[] args) 084  { 085  try 086  { 087  NNTPEx ne = new NNTPEx("new.server.com", 088  5000, 089  false, 090  "proxy.server.com", 091  119); 092   093  // open the connection to the server 094  ne.openConnection(); 095  // issue a command to the nntp server 096  ne.issueCommand("QUIT"); 097  // get news groups 098  Enumeration e = ne.getNewsGroups(); 099  // get the current newsgroup 100  NntpNewsgroup group = ne.getCurrentNewsGroup(); 101  // get number of articles 102  int count = group.getArticleCount(); 103  // get article headers 104  e = ne.getArticleHeaders(); 105  // get article by id 106  NntpArticle article = ne.getArticle(0); 107  // get the body of the article 108  String body = article.getBody(); 109  // get headers for article 110  Enumeration headers = article.getHeaders(); 111  // print out header name and value 112  while(headers.hasMoreElements()) 113  { 114  MimeHeader head = (MimeHeader)headers.nextElement(); 115  System.out.println(head.getName() + ": " + head.getValue());        116  } 117   118  // create new article 119  // First argument  : From header 120  // Second argument : Newsgroup header 121  // Third argument  : Subject header 122  NntpArticle artl = new NntpArticle("test@test.com","alt.test","Test post"); 123  artl.setBody("This is only a test"); 124   125  // post article 126  ne.postArticle(artl); 127   128  // close connection 129  ne.closeConnection(); 130  } 131  catch (Exception e) 132  { 133  e.printStackTrace(); 134  } 135  } 136 } Lines 1-4   : Necessary import statements. Lines 17-24 : Create a Nntp instance Lines 27-30 : Issue a command to the NNTP server. Lines 32-40 : Methods for opening and closing the connection to the NNTP server. Lines 42-50 : Event from NntpAdapter. Lines 57-60 : Add a newsgroup. Lines 62-65 : Get the current news group. Lines 67-71 : Get article headers. Lines 73-76 : Get article with a particular id. Lines 78-81 : Post an article. Go here for a detailed article on the Nntp protocol.

Reading MIME messages in Java

Overview 

     MIME is an Internet standard which has been extended to include text in character sets, non-text attachments, message bodies and header information in non-ASCII character sets. It's use has grown beyond describing the content type in general. This article will demonstrate how to use the mime component in Secure iNet Factory to read mime messages in Java.

Code Example

Download MimeParseEx.java

               

01 import com.jscape.inet.mime.*; 02 import java.io.*; 03 import java.util.*; 04 05 public class MimeParseEx 06 { 07  public static void main(String[] args) 08  { 09  try 10  { 11  // create new empty MimeMessage 12  MimeMessage message = new MimeMessage(); 13  // get contents of message 14  byte[] data = message.getMessage(); 15  // print to console 16  System.out.println(new String(data)); 17   18  // get all headers 19  Enumeration headers = message.getHeaders(); 20  while(headers.hasMoreElements()) 21  { 22  MimeHeader h = (MimeHeader)headers.nextElement(); 23  System.out.println(h.toString()); 24  } 25   26  // get Content-Type header 27  MimeHeader ct = message.getHeader("Content-Type"); 28  if(ct != null) 29  { 30  System.out.println(ct.toString()); 31  } 32   33  // get message body as a string 34  String body = message.getBody(); 35  // get message body as a byte[] 36  byte[] by = message.getBodyData(); 37   38  // get all parts 39  Enumeration e = message.getParts(); 40  // loop thru all parts 41  while(e.hasMoreElements()) 42  { 43  // get next part 44  message = (MimeMessage)e.nextElement(); 45  // print message contents to console 46  System.out.println(message.getMessage().toString()); 47  } 48  } 49  catch (Exception e) 50  { 51  e.printStackTrace(); 52  } 53  } 54 } Lines 1-3 : Necessary import statements. Line  12  : Create a new MimeMessage instance. Line  14  : Get the message as byte array. Lines 18-24 : Get all MimeHeader (s) in the MimeMessage instance. Lines 26-31 : Get a specific header. Lines 33-36 : Get the message body. Lines 38-47 : Get all the parts of a MimeMessage. A MIME Message may contain zero or               more parts. This code shows how to get those parts. Go here for a thorough overview of the MIME format.

Creating MIME compliant messages in Java

Overview 

     MIME is an Internet standard which has been extended to include text in character sets, non-text attachments, message bodies and header information in non-ASCII character sets. It's use has grown beyond describing the content type in general. This article will demonstrate how to use the mime component in Secure iNet Factory to create mime messages in Java.

Code Example

Download MIMEex.java

               

01 import java.io.*; 02 import com.jscape.inet.mime.*; 03 04 public class MIMEex 05 { 06  public static void main(String[] args) 07  { 08  String filename = "message.txt"; 09  // buffer to hold message data 10  byte[] data = null; 11  try 12  { 13  ByteArrayOutputStream bout = new ByteArrayOutputStream(); 14  DataInputStream din = 15  new DataInputStream(new FileInputStream(new File(filename))); 16  int b = 0; 17  while ((b = din.read()) != -1) bout.write(b); 18  data = bout.toByteArray(); 19  din.close(); 20   21  // construct new MimeMessage from existing data 22  MimeMessage msg = new MimeMessage(data); 23  // create new MIME header 24  MimeHeader header = new MimeHeader("Content-Disposition","attachment"); 25  // create new header attribute 26  MimeHeaderAttr file = new MimeHeaderAttr("filename","test.jpg"); 27  // add header attribute to header 28  header.addAttribute(file); 29  // add header 30  msg.addHeader(header); 31  // set message body 32  msg.setBody("This is the body"); 33   34   35  // body text for plain text part 36  String plainText = "This is plain text"; 37  // body text for html text part 38  String htmlText = "<b>This is HTML text</b>"; 39  // create parent message 40  MimeMessage contents = new MimeMessage(); 41  // set Content-Type header to multipart/alternative 42  contents.setContentType("multipart/alternative"); 43  // create plain text part and add to parent 44 45  MimeMessage plainMessage = new MimeMessage(); 46  plainMessage.setContentType("text/plain"); 47  plainMessage.setBody(plainText); 48  contents.addPart(plainMessage); 49 50  // create html text part and add to parent 51  MimeMessage htmlMessage = new MimeMessage(); 52  htmlMessage.setContentType("text/html"); 53  htmlMessage.setBody(htmlText); 54  contents.addPart(htmlMessage); 55  } 56  catch (Exception e) 57  { 58  e.printStackTrace(); 59  } 60  } 61 } Lines 1-2   : Necessary import statements. Lines 13-19 : Create a DataInputStream from the text file and place the data into a               byte array. Lines 21-32 : Create a MimeMessage and add a MimeHeader to it. The MimeHeader may contain               zero or more attributes. Each attribute has a name and a value. Lines 35-54 : Create a new MimeMessage by adding one MIME message to another. Go here for a thorough overview of the MIME format.

Creating SSL/TLS TCP/IP connections in Java

Overview 

     The article will demonstrate how to use the ipclient component in Secure iNet Factory to create SSL/TLS TCP/IP client socket connections.

Code Example

Download IPClientSSLEx.java

               

01 import java.io.*; 02 03 import com.jscape.inet.ipclient.IpClientConnectedEvent; 04 import com.jscape.inet.ipclient.IpClientDisconnectedEvent; 05 import com.jscape.inet.ipclient.IpClientListener; 06 import com.jscape.inet.ipclientssl.IpClientSsl; 07 08 09 public class IPClientSSLEx implements IpClientListener 10 { 11  public static void main(String[] args) 12  { 13  try 14  { 15  String hostname = "hostname"; 16  int port = -1; 17  // create new IpClientSsl instance 18  IpClientSsl ssl = new IpClientSsl(hostname,port); 19 20  // establish a connection 21  ssl.connect(); 22 23  // get input stream 24  InputStream in = ssl.getInputStream(); 25   26  // read data from input stream 27  int i = 0; 28  while((i = in.read()) != -1) { 29  // do something with data        30  } 31   32  // get output stream for tunnel 33  OutputStream out = ssl.getOutputStream(); 34  // write data to output stream 35  byte[] buffer = new byte[1024]; 36  out.write(buffer); 37 38  ssl.disconnect(); 39  } 40  catch (Exception e) 41  { 42  e.printStackTrace(); 43  } 44  } 45 46  public void connected(IpClientConnectedEvent event) 47  { 48  System.out.println("Connected to host: " + event.getHostname()); 49  } 50 51  public void disconnected(IpClientDisconnectedEvent event) 52  { 53  System.out.println("Disconnected from host: " + event.getHostname()); 54  } 55 } Lines 1-6 : Necessary import statements. Line 18   : Create IpClientSsl instance. Line 21   : Connect to the host. Lines 23-32 : Read the data from the ssl tunnel. Line 38     : Disconnect from the host.

Creating TCP/IP client socket connections through SSH in Java

Overview 

     The article will demonstrate how to use the ipclient component in Secure iNet Factory to create TCP/IP client socket connections over SSH.

     To demonstrate, consider the POP (Post Office Protocol) service which allows you to retrieve email from your account mailbox.  To retrieve your email you must submit a username and password.  This username and password is usually sent to the POP service in clear text making it susceptible to snooping on the network.  While this may not be a concern on your own corporate intranet it becomes an immediate concern when accessing your account remotely via the public Internet. 

     To address this issue you can create a secure SSH tunnel that encrypts data while travelling over the Internet.  An SSH tunnel is a special type of SSH connection where all data sent by the client is securely routed to a specified destination hostname/port and any data received from that hostname/port is securely sent back through the SSH tunnel to the client. 

 

Code Example

Download IPClientSSHEx.java

               

01 import java.io.*; 02 import com.jscape.inet.ipclient.IpClientConnectedEvent; 03 import com.jscape.inet.ipclient.IpClientDisconnectedEvent; 04 import com.jscape.inet.ipclient.IpClientListener; 05 import com.jscape.inet.ipclientssh.IpClientSsh; 06 import com.jscape.inet.ssh.util.SshParameters; 07 08 public class IPClientSSHEx implements IpClientListener 09 { 10  public static void main(String[] args) 11  { 12  try 13  { 14  // SSH hostname 15  String sshHostname = "myhost.com"; 16  // SSH username 17  String sshUsername = "jsmith"; 18  // SSH password 19  String sshPassword = "secret"; 20  // POP3 service hostname 21  String popHostname = "myhost.com"; 22  // POP3 service port 23  int popPort = 110; 24  // create SSH authentication info 25  SshParameters sshParams = new SshParameters(sshHostname,sshUsername,sshPassword); 26   27  // create new tunnel to specified POP3 server hostname and POP3 service port 28  IpClientSsh tunnel = new IpClientSsh(sshParams,popHostname,popPort); 29   30  // establish tunnel 31  tunnel.connect(); 32   33  // get input stream for tunnel 34  InputStream in = tunnel.getInputStream(); 35 36  // read data from input stream 37  int b = 0; 38  while((b = in.read()) != -1) { 39  // do something with data 40  } 41   42  // get output stream for tunnelte 43  byte[] buffer = new byte[1024]; 44  OutputStream out = tunnel.getOutputStream(); 45  out.write(buffer); 46   47  // disconnect 48  tunnel.disconnect(); 49  } 50  catch (Exception e) 51  { 52  e.printStackTrace(); 53  } 54  } 55 56 57  public void connected(IpClientConnectedEvent event) 58  { 59  System.out.println("Connected to host: " + event.getHostname()); 60  } 61 62 63  public void disconnected(IpClientDisconnectedEvent event) 64  { 65  System.out.println("Disconnected from host: " + event.getHostname()); 66  } 67 68 } Lines 1-6  : Necessary import statements. Line 25    : Create a SshParameters instance with the hostname, username and password. Line 28    : Create a IpClientSsh instance. Line 31    : Connect to the host. Line 34-45 : Read the input stream Line 48    : Disconnect from the host