From cb90852dfcc9226edaadff16f880db46be791e67 Mon Sep 17 00:00:00 2001
From: Brock Whitten <brock@sintaxi.com>
Date: Wed, 24 Feb 2010 16:18:35 -0800
Subject: [PATCH] Adding Built-In Crypto Library

---
 framework/src/com/phonegap/CryptoHandler.java | 37 +++++++
 framework/src/com/phonegap/DroidGap.java      |  8 +-
 framework/src/com/phonegap/SimpleCrypto.java  | 96 +++++++++++++++++++
 3 files changed, 138 insertions(+), 3 deletions(-)
 create mode 100644 framework/src/com/phonegap/CryptoHandler.java
 create mode 100644 framework/src/com/phonegap/SimpleCrypto.java

diff --git a/framework/src/com/phonegap/CryptoHandler.java b/framework/src/com/phonegap/CryptoHandler.java
new file mode 100644
index 00000000..ac6b26cc
--- /dev/null
+++ b/framework/src/com/phonegap/CryptoHandler.java
@@ -0,0 +1,37 @@
+package com.phonegap;
+
+import android.webkit.WebView;
+
+public class CryptoHandler {
+	
+	WebView mView;
+	
+	CryptoHandler(WebView view)
+	{
+		mView = view;
+	}
+	
+	public void encrypt(String pass, String text)
+	{
+		try {
+			String encrypted = SimpleCrypto.encrypt(pass,text);
+			mView.loadUrl("javascript:Crypto.gotCryptedString('" + text + "')");
+		} catch (Exception e) {
+			// TODO Auto-generated catch block
+			e.printStackTrace();
+		}
+		
+	}
+	
+	public void decrypt(String pass, String text)
+	{
+		try {
+			String decrypted = SimpleCrypto.decrypt(pass,text);
+			mView.loadUrl("javascript:Crypto.gotPlainString('" + text + "')");
+		} catch (Exception e) {
+			// TODO Auto-generated catch block
+			e.printStackTrace();
+		}
+	}
+	
+}
diff --git a/framework/src/com/phonegap/DroidGap.java b/framework/src/com/phonegap/DroidGap.java
index bb96a73a..b2954ecc 100644
--- a/framework/src/com/phonegap/DroidGap.java
+++ b/framework/src/com/phonegap/DroidGap.java
@@ -60,8 +60,7 @@ public class DroidGap extends Activity {
 	private NetworkManager netMan;
 	private CompassListener mCompass;
 	private Storage	cupcakeStorage;
-	
-	
+	private CryptoHandler crypto;
 	
     /** Called when the activity is first created. */
 	@Override
@@ -134,7 +133,8 @@ public class DroidGap extends Activity {
     	mContacts = new ContactManager(this, appView);
     	fs = new FileUtils(appView);
     	netMan = new NetworkManager(this, appView);
-    	mCompass = new CompassListener(this, appView);    	    	
+    	mCompass = new CompassListener(this, appView);  
+    	crypto = new CryptoHandler(appView);
     	
     	// This creates the new javascript interfaces for PhoneGap
     	appView.addJavascriptInterface(gap, "DroidGap");
@@ -145,6 +145,8 @@ public class DroidGap extends Activity {
     	appView.addJavascriptInterface(fs, "FileUtil");
     	appView.addJavascriptInterface(netMan, "NetworkManager");
     	appView.addJavascriptInterface(mCompass, "CompassHook");
+    	appView.addJavascriptInterface(crypto, "GapCrypto");
+    	
     	if (android.os.Build.VERSION.SDK_INT <= android.os.Build.VERSION_CODES.DONUT)
     	{
     		cupcakeStorage = new Storage(appView);
diff --git a/framework/src/com/phonegap/SimpleCrypto.java b/framework/src/com/phonegap/SimpleCrypto.java
new file mode 100644
index 00000000..1f877427
--- /dev/null
+++ b/framework/src/com/phonegap/SimpleCrypto.java
@@ -0,0 +1,96 @@
+/*
+ * Code originally found on Android Snippets
+ * Contributed to snippets Ferenc Hechler
+ * Copyright (c) 2009 Ferenc Hechler
+ */
+
+package com.phonegap;
+
+import java.security.SecureRandom;
+
+import javax.crypto.Cipher;
+import javax.crypto.KeyGenerator;
+import javax.crypto.SecretKey;
+import javax.crypto.spec.SecretKeySpec;
+
+public class SimpleCrypto {
+	
+	public static String encrypt(String seed, String cleartext) throws Exception {
+		byte[] rawKey = getRawKey(seed.getBytes());
+		byte[] result = encrypt(rawKey, cleartext.getBytes());
+		return toHex(result);
+	}
+	
+	public static String decrypt(String seed, String encrypted) throws Exception {
+		byte [] rawKey = getRawKey(seed.getBytes());
+		byte [] enc = toByte(encrypted);
+		byte [] result = decrypt(rawKey, enc);
+		return new String(result);
+	}
+	
+	public static byte[] getRawKey(byte [] seed) throws Exception {
+		KeyGenerator kgen = KeyGenerator.getInstance("AES");
+		SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");
+		sr.setSeed(seed);
+		kgen.init(128, sr);
+		SecretKey skey = kgen.generateKey();
+		byte[] raw = skey.getEncoded();
+		return raw;
+	}
+	
+	private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception {
+		SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
+		Cipher cipher = Cipher.getInstance("AES");
+		cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
+		byte[] encrypted = cipher.doFinal(clear);
+		return encrypted;
+	}
+	
+	private static byte[] decrypt(byte[] raw, byte[] encrypted) throws Exception {
+		SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
+		Cipher cipher = Cipher.getInstance("AES");
+		cipher.init(Cipher.DECRYPT_MODE, skeySpec);
+		byte[] decrypted = cipher.doFinal(encrypted);
+		return decrypted;
+	}
+	
+	public static String toHex(String txt)
+	{
+		return toHex(txt.getBytes());
+	}
+	
+	public static String fromHex(String hex)
+	{
+		return new String(toByte(hex));
+	}
+	
+	public static byte[] toByte(String hexString) {
+		int len = hexString.length()/2;
+		byte[] result = new byte[len];
+		for (int i = 0; i < len; ++i)
+		{
+			result[i] = Integer.valueOf(hexString.substring(2*i, 2*i+2), 16).byteValue();
+		}
+		return result;
+	}
+	
+	public static String toHex(byte[] buf) {
+		if (buf == null)
+		{
+			return "";
+		}
+		StringBuffer result = new StringBuffer(2*buf.length);
+		for (int i = 0; i < buf.length; i++)
+		{
+			appendHex(result, buf[i]);
+		}
+		return result.toString();
+	}
+	
+	private final static String HEX = "01234567890ABCDEF";
+	
+	private static void appendHex(StringBuffer sb, byte b)
+	{
+		sb.append(HEX.charAt((b>>4)&0x0f)).append(HEX.charAt(b&0x0f));
+	}
+}
\ No newline at end of file