From: bdemsky <bdemsky@uci.edu>
Date: Tue, 26 Jul 2016 23:26:33 +0000 (-0700)
Subject: add crypt to slots
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=iotcloud.git;a=commitdiff_plain;h=a58d3a3a3a51e36f3c29a3817e765f1c2516cd90

add crypt to slots
---

diff --git a/src/java/iotcloud/CloudComm.java b/src/java/iotcloud/CloudComm.java
index b5aca62..49217ec 100644
--- a/src/java/iotcloud/CloudComm.java
+++ b/src/java/iotcloud/CloudComm.java
@@ -16,12 +16,13 @@ import java.security.SecureRandom;
 
 class CloudComm {
 	String baseurl;
-	Cipher encryptcipher;
-	Cipher decryptcipher;
+	Cipher encryptCipher;
+	Cipher decryptCipher;
 	Mac mac;
-	byte[] salt;
-	SecretKeySpec key;
+	String password;
+	SecureRandom random;
 	static final int SALT_SIZE = 8;
+	static final int IV_SIZE = 16;
 
 	/**
 	 * Empty Constructor needed for child class.
@@ -34,21 +35,21 @@ class CloudComm {
 	 * Constructor for actual use. Takes in the url and password.
 	 */
 
-	CloudComm(String _baseurl, String password) {
+	CloudComm(String _baseurl, String _password) {
 		this.baseurl=_baseurl;
-		initCloud(password);
+		this.password = _password;
+		this.random = new SecureRandom();
 	}
 
 	/**
 	 * Generates Key from password.
 	 */
 
-	private void initKey(String password) {
+	private SecretKeySpec initKey(byte[] salt) {
 		try {
-			salt=new byte[SALT_SIZE];
 			PBEKeySpec keyspec = new PBEKeySpec(password.toCharArray(), salt, 65536, 128);
 			SecretKey tmpkey = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256").generateSecret(keyspec);
-			this.key = new SecretKeySpec(tmpkey.getEncoded(), "AES");
+			return new SecretKeySpec(tmpkey.getEncoded(), "AES");
 		} catch (Exception e) {
 			e.printStackTrace();
 			throw new Error("Failed generating key.");
@@ -59,11 +60,27 @@ class CloudComm {
 	 * Inits the HMAC generator.
 	 */
 
-	private void initCloud(String password) {
+	private byte[] initCrypt(byte[] salt) {
 		try {
-			initKey(password);
+			SecretKeySpec key=initKey(salt);
 			mac = Mac.getInstance("HmacSHA256");
 			mac.init(key);
+			encryptCipher =Cipher.getInstance("AES/CBC/PKCS5Padding");
+			encryptCipher.init(Cipher.ENCRYPT_MODE, key);
+			return encryptCipher.getIV();
+		} catch (Exception e) {
+			e.printStackTrace();
+			throw new Error("Failed To Initialize Ciphers");
+		}
+	}
+
+	private void initDeCrypt(byte[] salt, byte[] iv) {
+		try {
+			SecretKeySpec key=initKey(salt);
+			mac = Mac.getInstance("HmacSHA256");
+			mac.init(key);
+			Cipher decryptCipher =Cipher.getInstance("AES/CBC/PKCS5Padding");
+			decryptCipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
 		} catch (Exception e) {
 			e.printStackTrace();
 			throw new Error("Failed To Initialize Ciphers");
@@ -91,8 +108,11 @@ class CloudComm {
 	public Slot[] putSlot(Slot slot, int max) {
 		try {
 			long sequencenumber=slot.getSequenceNumber();
+			byte[] salt=new byte[SALT_SIZE];
+			random.nextBytes(salt);
+			byte[] iv=initCrypt(salt);
+			
 			byte[] bytes=slot.encode(mac);
-
 			URL url=buildRequest(true, sequencenumber, max);
 			URLConnection con=url.openConnection();
 			HttpURLConnection http = (HttpURLConnection) con;
@@ -100,7 +120,11 @@ class CloudComm {
 			http.setFixedLengthStreamingMode(bytes.length);
 			http.setDoOutput(true);
 			http.connect();
+
 			OutputStream os=http.getOutputStream();
+			os.write(salt);
+			os.write(iv);
+			bytes = encryptCipher.doFinal(bytes);
 			os.write(bytes);
 
 			InputStream is=http.getInputStream();
@@ -118,15 +142,6 @@ class CloudComm {
 		}
 	}
 
-	/*
-	                Cipher encryptCipher =
-	                Cipher.getInstance("AES/CBC/PKCS5Padding");
-	                encryptCipher.init(Cipher.ENCRYPT_MODE, secret);
-	                Cipher decryptCipher =
-	                Cipher.getInstance("AES/CBC/PKCS5Padding");
-	                decryptCipher.init(Cipher.DECRYPT_MODE, secret);
-	 */
-
 	/**
 	 * Request the server to send all slots with the given
 	 * sequencenumber or newer.
@@ -142,6 +157,7 @@ class CloudComm {
 			InputStream is=http.getInputStream();
 
 			DataInputStream dis=new DataInputStream(is);
+			
 			byte[] resptype=new byte[7];
 			dis.readFully(resptype);
 			if (!Arrays.equals(resptype, "getslot".getBytes()))
@@ -158,7 +174,7 @@ class CloudComm {
 	 * server response.  Shared by both putSlot and getSlots.
 	 */
 
-	private Slot[] processSlots(DataInputStream dis) throws IOException {
+	private Slot[] processSlots(DataInputStream dis) throws Exception {
 		int numberofslots=dis.readInt();
 		int[] sizesofslots=new int[numberofslots];
 		Slot[] slots=new Slot[numberofslots];
@@ -166,8 +182,17 @@ class CloudComm {
 			sizesofslots[i]=dis.readInt();
 
 		for(int i=0; i<numberofslots; i++) {
+			byte[] salt=new byte[SALT_SIZE];
+			byte[] iv=new byte[IV_SIZE];
+			dis.readFully(salt);
+			dis.readFully(iv);
+			initDeCrypt(salt, iv);
+
 			byte[] data=new byte[sizesofslots[i]];
 			dis.readFully(data);
+
+			data = decryptCipher.doFinal(data);
+
 			slots[i]=Slot.decode(data, mac);
 		}
 		dis.close();