From: bdemsky <bdemsky@uci.edu>
Date: Sun, 24 Jul 2016 07:37:27 +0000 (-0700)
Subject: edits
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=bc506d6cd14fc4af1bb89ef612920ccdc6c10565;p=iotcloud.git

edits
---

diff --git a/src/java/iotcloud/CloudComm.java b/src/java/iotcloud/CloudComm.java
index 84d7ae4..85f6b08 100644
--- a/src/java/iotcloud/CloudComm.java
+++ b/src/java/iotcloud/CloudComm.java
@@ -3,23 +3,52 @@ import java.io.*;
 import java.net.*;
 import java.util.Arrays;
 import javax.crypto.*;
+import javax.crypto.spec.*;
+import java.security.SecureRandom;
 
 class CloudComm {
 	String baseurl;
 	Cipher encryptcipher;
 	Cipher decryptcipher;
 	Mac mac;
+	byte[] salt;
+	SecretKeySpec key;
+	static final int SALT_SIZE = 8;
 
+	
 	CloudComm() {
 	}
 
-	CloudComm(String _baseurl, Cipher _encrypt, Cipher _decrypt, Mac _mac) {
+	CloudComm(String _baseurl, String password) {
 		this.baseurl=_baseurl;
-		this.encryptcipher = _encrypt;
-		this.decryptcipher = _decrypt;
-		this.mac = _mac;
+		initCloud(password);
 	}
 
+	private void initKey(String password) {
+		try {
+			salt=new byte[SALT_SIZE];
+			SecureRandom random = new SecureRandom();
+			random.nextBytes(salt);
+			PBEKeySpec keyspec = new PBEKeySpec(password.toCharArray(), salt, 65536, 128);
+			SecretKey key = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256").generateSecret(keyspec);
+			key = new SecretKeySpec(key.getEncoded(), "AES");
+		} catch (Exception e) {
+			e.printStackTrace();
+			throw new Error("Failed generating key.");
+		}
+	}
+
+	private void initCloud(String password) {
+		try {
+			initKey(password);
+			mac = Mac.getInstance("HmacSHA256");
+			mac.init(key);
+		} catch (Exception e) {
+			e.printStackTrace();
+			throw new Error("Failed To Initialize Ciphers");
+		}
+	}
+	
 	private URL buildRequest(boolean isput, long sequencenumber, long maxentries) throws IOException {
 		String reqstring=isput?"req=putslot":"req=getslot";
 		String urlstr=baseurl+"?"+reqstring+"&seq="+sequencenumber;
@@ -37,10 +66,11 @@ class CloudComm {
 			URLConnection con=url.openConnection();
 			HttpURLConnection http = (HttpURLConnection) con;
 			http.setRequestMethod("POST");
-			http.setFixedLengthStreamingMode(bytes.length);
+			http.setFixedLengthStreamingMode(bytes.length + SALT_SIZE);
 			http.setDoOutput(true);
 			http.connect();
 			OutputStream os=http.getOutputStream();
+			os.write(salt);
 			os.write(bytes);
 			System.out.println(http.getResponseMessage());
 
@@ -59,6 +89,13 @@ 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);
+	*/
+	
 	public Slot[] getSlots(long sequencenumber) {
 		try {
 			URL url=buildRequest(false, sequencenumber, 0);
diff --git a/src/java/iotcloud/Table.java b/src/java/iotcloud/Table.java
index c92aef9..1d27932 100644
--- a/src/java/iotcloud/Table.java
+++ b/src/java/iotcloud/Table.java
@@ -2,8 +2,6 @@ package iotcloud;
 import java.util.HashMap;
 import java.util.Arrays;
 import java.util.Vector;
-import javax.crypto.spec.*;
-import javax.crypto.*;
 
 final public class Table {
 	private int numslots;
@@ -11,7 +9,6 @@ final public class Table {
 	private HashMap<Long, Pair<Long, Liveness> > lastmessagetable=new HashMap<Long, Pair<Long, Liveness> >();
 	private SlotBuffer buffer;
 	private CloudComm cloud;
-	private Mac hmac;
 	private long sequencenumber;
 	private long localmachineid;
 	private TableStatus lastTableStatus;
@@ -23,7 +20,7 @@ final public class Table {
 		buffer = new SlotBuffer();
 		numslots = buffer.capacity();
 		sequencenumber = 0;
-		initCloud(baseurl, password);
+		cloud=new CloudComm(baseurl, password);
 	}
 
 	public Table(CloudComm _cloud, long _localmachineid) {
@@ -34,32 +31,6 @@ final public class Table {
 		cloud=_cloud;
 	}
 
-	private void initCloud(String baseurl, String password) {
-		try {
-			SecretKeySpec secret=getKey(password);
-			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);
-			hmac = Mac.getInstance("HmacSHA256");
-			hmac.init(secret);
-			cloud=new CloudComm(baseurl, encryptCipher, decryptCipher, hmac);
-		} catch (Exception e) {
-			throw new Error("Failed To Initialize Ciphers");
-		}
-	}
-
-	private SecretKeySpec getKey(String password) {
-		try {
-			PBEKeySpec keyspec = new PBEKeySpec(password.toCharArray());
-			SecretKey key = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256").generateSecret(keyspec);
-			SecretKeySpec secret = new SecretKeySpec(key.getEncoded(), "AES");
-			return secret;
-		} catch (Exception e) {
-			throw new Error("Failed generating key.");
-		}
-	}
-
 	public void update() {
 		Slot[] newslots=cloud.getSlots(sequencenumber+1);