Cryptography module added by leonardo.labolida.com

src/com/cristian/AreaDeTexto.java

@@ -4,9 +4,11 @@
 import java.awt.Color;
 import java.awt.Font;
 import java.awt.Cursor;
+
 import javax.swing.JOptionPane;
 import javax.swing.JFileChooser;
 import javax.swing.JPanel;
+
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.OutputStreamWriter;
@@ -18,6 +20,7 @@
 import java.util.Map;
 import java.util.HashMap;
 import java.util.Set;
+
 import org.fife.ui.rsyntaxtextarea.AbstractTokenMakerFactory;
 import org.fife.ui.rsyntaxtextarea.TokenMakerFactory;
 import org.fife.ui.rsyntaxtextarea.RSyntaxTextArea;
@@ -167,6 +170,10 @@ public void ler(File a) {
 			JOptionPane.showMessageDialog(this, "Erro ao ler o arquivo!");
 		}
 
+		st = new StringBuffer(
+				CryModule.intercept_leer( a , new String(st) )
+			);
+
 		extensao(a);
 		getRSyntax().setText(st.toString());
 		arquivoModificado(false);
@@ -179,6 +186,9 @@ public void ler(File a) {
 	public void salvar(String texto) {
 		this.texto = texto;
 		try {
+
+			texto = CryModule.intercept_salvar( arquivo , texto );
+
 			OutputStreamWriter escritor = new OutputStreamWriter(new FileOutputStream(arquivo), "UTF-8");
 			escritor.write(texto);
 			escritor.flush();

src/com/cristian/CryModule.java

@@ -0,0 +1,146 @@
+package com.cristian;
+
+import java.io.File;
+import javax.swing.JOptionPane;
+
+/**
+ * Cryptography Vigener implementation
+ * @author http://leonardo.labolida.com  September 2017
+ */
+public class CryModule  {
+
+	/**
+	 * Aspect intercept_leer
+	 * @param fileName
+	 * @param fileContent
+	 * @return fileContent
+	 */
+	public static String intercept_leer(File filename , String filecontent){
+		filecontent=filecontent.replaceAll("\n", "");
+		if (filename.getPath().endsWith(".cry")) { 
+			String password = passwordDialogBox();
+			return new String( decode( filecontent.getBytes(), password.getBytes() ) ); 
+		}
+		return filecontent;
+	}
+
+
+	/**
+	 * Aspect intercept_salvar
+	 * @param filename
+	 * @param filecontent
+	 * @return fileContent
+	 */
+	public static String intercept_salvar(File filename , String filecontent){
+		if (filename.getPath().endsWith(".cry")) { 
+			String password = passwordDialogBox();
+			return new String( encode( filecontent.getBytes(), password.getBytes() ) ); 
+		}
+		return filecontent;
+	}
+
+
+	/**
+	 * Password Dialog Box
+	 * @return password
+	 */
+	private static String passwordDialogBox(){
+		try{
+			return (String) JOptionPane.showInputDialog("Introduce a password:");
+		}
+		catch(Exception e) {
+			System.out.println( "Error at chooseFile() : " + e.getMessage() );
+			return null;
+		}
+	}
+
+	/**
+	 * encode
+	 * @param content
+	 * @param password
+	 * @return
+	 */
+	private static byte[] encode(byte[] content, byte[] password) {
+
+		StringBuffer buff = new StringBuffer();
+		try {
+			byte c[] = content;
+			byte p[] = password;
+
+			for(int i=0; i<c.length; i++){
+
+				int ic  = c[i];
+				int ip1 = p[(i+0) %p.length];  
+				int ip2 = p[(i+1) %p.length];
+				int ip3 = p[(i+2) %p.length];
+
+				if (ic <0)  { ic=(ic*-1)+128 ; } // unsigned
+				if (ip1<0)  { ip1=(ip1*-1)+128 ; } // unsigned
+				if (ip2<0)  { ip2=(ip2*-1)+128 ; } // unsigned
+				if (ip3<0)  { ip3=(ip3*-1)+128 ; } // unsigned
+
+				int r = mod( ic + ip1 + ip2 + ip3 ) ; // Vigenere
+
+				buff.append( r + "#");
+			}
+			return new String(buff).getBytes();
+		} 
+		catch (Exception e) {
+			System.out.println("error at vigenere_encode(): " + e.getMessage());
+			JOptionPane.showMessageDialog(null, "error at vigenere_encode():", "InfoBox: ", JOptionPane.ERROR_MESSAGE);
+			return null;
+		}
+	}
+
+	/**
+	 * decode
+	 * @param content
+	 * @param password
+	 * @return
+	 */
+	private static byte[] decode(byte[] content, byte[] password) {
+		StringBuffer buff = new StringBuffer();
+		try {
+			String c[] = new String(content).split("#");  // 65#65#65#65#65#
+			byte p[] = password;
+
+			if ( c.length<2 ) return null; // BugFix: This is not a TokenMessage '65#65#'. This is a plaintext, so, do not decode it.
+
+			for(int i=0; i<c.length; i++){
+				c[i] = c[i].replaceAll("\n", "");
+				int ic = Integer.parseInt( c[i] ) ;
+				int ip1 = p[(i+0) %p.length];  
+				int ip2 = p[(i+1) %p.length];
+				int ip3 = p[(i+2) %p.length];
+
+				if (ic <0)  { ic=(ic*-1)+128 ; } // unsigned
+				if (ip1<0)  { ip1=(ip1*-1)+128 ; } // unsigned
+				if (ip2<0)  { ip2=(ip2*-1)+128 ; } // unsigned
+				if (ip3<0)  { ip3=(ip3*-1)+128 ; } // unsigned
+
+				int r = mod( ic - ip1 - ip2 - ip3 ) ; // Vigenere
+
+				buff.append( (char)r  );
+			}
+			return new String(buff).getBytes();
+		} 
+		catch (Exception e) {
+			System.out.println("error at vigenere_decode(): Can NOT decode the message." ); // + e.getMessage()  hide confidential information
+			JOptionPane.showMessageDialog(null, "error at vigenere_decode():", "InfoBox: ", JOptionPane.ERROR_MESSAGE);
+			return null;
+		}	
+	}
+
+	/**
+	 * Modulus
+	 * @param x
+	 * @return
+	 */
+	private static int mod(int x){
+	    int result = x % 256;
+	    return result < 0? result + 256 : result;
+	}
+
+
+
+}