From 1949083bec8c238d38683d4755a0a4a4fe11b111 Mon Sep 17 00:00:00 2001
From: Björn Hagemeister
Date: Wed, 15 Oct 2014 15:12:48 +0200
Subject: Implemented --genId command line option.

---
 .../java/org/openslx/satellitedaemon/Identity.java | 124 ++++++++++++++++++---
 1 file changed, 110 insertions(+), 14 deletions(-)

(limited to 'src/main/java/org/openslx/satellitedaemon/Identity.java')

diff --git a/src/main/java/org/openslx/satellitedaemon/Identity.java b/src/main/java/org/openslx/satellitedaemon/Identity.java
index 92bf425..6e5c877 100644
--- a/src/main/java/org/openslx/satellitedaemon/Identity.java
+++ b/src/main/java/org/openslx/satellitedaemon/Identity.java
@@ -1,6 +1,9 @@
 package org.openslx.satellitedaemon;
 
+import java.io.File;
 import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.math.BigInteger;
@@ -10,6 +13,7 @@ import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.spec.InvalidKeySpecException;
 import java.util.Properties;
+import java.util.Random;
 
 import org.apache.log4j.Logger;
 import org.openslx.encryption.AsymKeyHolder;
@@ -20,26 +24,31 @@ public class Identity
 	private static Logger log = Logger.getLogger( Identity.class );
 	private static final Properties properties = new Properties();
 
+	private static String organizationName = null;
+	private static BigInteger privExponent = null;
+	private static BigInteger pubExponent = null;
+	private static BigInteger modulus = null;
+
 	private static AsymKeyHolder akh = null;
 
 	public static String getOrganizationName()
 	{
-		return properties.getProperty( "ORGANIZATION_NAME" );
+		return organizationName = properties.getProperty( "ORGANIZATION_NAME" );
 	}
 
 	private static BigInteger getModulus()
 	{
-		return toBigInt( properties.getProperty( "MODULUS" ) );
+		return modulus = toBigInt( properties.getProperty( "MODULUS" ) );
 	}
 
 	private static BigInteger getPublicExponent()
 	{
-		return toBigInt( properties.getProperty( "PUBLIC_EXPONENT" ) );
+		return pubExponent = toBigInt( properties.getProperty( "PUBLIC_EXPONENT" ) );
 	}
 
 	private static BigInteger getPrivateExponent()
 	{
-		return toBigInt( properties.getProperty( "PRIVATE_EXPONENT" ) );
+		return privExponent = toBigInt( properties.getProperty( "PRIVATE_EXPONENT" ) );
 	}
 
 	/**
@@ -99,22 +108,109 @@ public class Identity
 
 	/**
 	 * Get bit - length of key.
+	 * 
 	 * @return
 	 */
-	public static int keySize() {
-		if (getModulus() != null) 
-			return getModulus().bitLength();
-		return -1;
+	public static int keySize( BigInteger modulus )
+	{
+		return modulus.bitLength();
 	}
-	
-	public static boolean checkMembers() {
-		return (
-				(getModulus() != null) &&
-				(getPrivateExponent() != null) &&
-				(getPublicExponent() != null));
+
+	/**
+	 * Checks if given modulus, private exponent and public exponent are valid
+	 * values for key pair. Idea is to encrypt and decrypt random text and compare
+	 * the result with initial text.
+	 * 
+	 * @param mod
+	 * @param privExp
+	 * @param pubExp
+	 * @return True, if mod, privExp and pubExp are valid values.
+	 */
+	public static boolean isValidKeyPair( BigInteger mod, BigInteger privExp, BigInteger pubExp )
+	{
+		// First check given values (modulus, privExp, pubExp).
+		if ( ( mod == null ) || ( privExp == null ) || ( pubExp == null ) ) {
+			log.error( "Given arguments not valid: got NULL for modulus, private or public exponent." );
+			return false;
+		}
+
+		// Testing encryption and description with given public and private key.
+		// Idea: creating random text for encrypting and decrypting again.
+		Random rnd = new Random();
+		int size = rnd.nextInt( keySize( mod ) - 1 );
+		BigInteger text = new BigInteger( size, rnd );
+		// Encrypt.
+		BigInteger cipher = text.modPow( pubExp, mod );
+		// Decrypt again.
+		BigInteger decrypted = cipher.modPow( privExp, mod );
+		boolean isPassed = text.equals( decrypted );
+		return isPassed;
+	}
+
+	public static boolean generateIdentity( String organizationName )
+	{
+		Identity.organizationName = organizationName;
+		// generate new key pair.
+		Identity.akh = new AsymKeyHolder();
+		Identity.modulus = akh.getModulus();
+		Identity.privExponent = akh.getPrivateExponent();
+		Identity.pubExponent = akh.getPublicExponent();
+
+		return writeIdToFile(
+				Identity.organizationName,
+				Identity.modulus,
+				Identity.privExponent,
+				Identity.pubExponent );
 	}
+
+	private static boolean writeIdToFile( String organizationName, BigInteger modulus, BigInteger privateExp, BigInteger publicExp )
+	{
+		File configFile = new File( "config/identity.properties" );
+		FileOutputStream stream = null;
+		try {
+			stream = new FileOutputStream( configFile );
+		} catch ( FileNotFoundException e ) {
+			log.error( "FileNotFoundException", e );
+			return false;
+		}
+		
+		// create strings for writing to file. 
+		String orgNameString = "ORGANIZATION_NAME=" + organizationName + "\n";
+		String modString = "MODULUS=" + modulus.toString() + "\n";
+		String privExpString = "PRIVATE_EXPONENT=" + privateExp.toString() + "\n";
+		String pubExpString = "PUBLIC_EXPONENT=" + publicExp.toString() + "\n";
+
+		try {
+			stream.write( orgNameString.getBytes() );
+			stream.write( modString.getBytes() );
+			stream.write( privExpString.getBytes() );
+			stream.write( pubExpString.getBytes() );
+			return true;
+		} catch ( IOException e ) {
+			log.error( "IOException", e );
+			return false;
+		} finally {
+			try {
+				stream.close();
+			} catch ( IOException e ) {
+			}
+		}
+	}
+
+	/**
+	 * Check modulus, privExp and pubExp for not being null.
+	 * 
+	 * @return
+	 */
+	private static boolean checkMembers()
+	{
+		return ( ( getModulus() != null ) &&
+				( getPrivateExponent() != null ) && ( getPublicExponent() != null ) );
+	}
+
 	/**
 	 * Get BigInteger of read String number.
+	 * 
 	 * @param str
 	 * @return
 	 */
-- 
cgit v1.2.3-55-g7522