package iotcloud;
+
import java.io.*;
import java.net.*;
import java.util.Arrays;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.security.SecureRandom;
+import java.nio.ByteBuffer;
/**
* This class provides a communication API to the webserver. It also
class CloudComm {
- String baseurl;
- Cipher encryptCipher;
- Cipher decryptCipher;
- Mac mac;
- String password;
- SecureRandom random;
- static final int SALT_SIZE = 8;
- byte salt[];
- Table table;
+ private static final int SALT_SIZE = 8;
+ private static final int TIMEOUT_MILLIS = 2000; // 100
+ public static final int IV_SIZE = 16;
+
+ /** Sets the size for the HMAC. */
+ static final int HMAC_SIZE = 32;
+
+ private String baseurl;
+ private SecretKeySpec key;
+ private Mac mac;
+ private String password;
+ private SecureRandom random;
+ private byte salt[];
+ private Table table;
+ private int listeningPort = -1;
+ private Thread localServerThread = null;
+ private boolean doEnd = false;
+
+ private TimingSingleton timer = null;
/**
* Empty Constructor needed for child class.
*/
-
CloudComm() {
+ timer = TimingSingleton.getInstance();
}
/**
* Constructor for actual use. Takes in the url and password.
*/
-
- CloudComm(Table _table, String _baseurl, String _password) {
+ CloudComm(Table _table, String _baseurl, String _password, int _listeningPort) {
+ timer = TimingSingleton.getInstance();
this.table = _table;
this.baseurl = _baseurl;
this.password = _password;
this.random = new SecureRandom();
+ this.listeningPort = _listeningPort;
+
+ if (this.listeningPort > 0) {
+ localServerThread = new Thread(new Runnable() {
+ public void run() {
+ localServerWorkerFunction();
+ }
+ });
+ localServerThread.start();
+ }
}
/**
* Generates Key from password.
*/
-
private SecretKeySpec initKey() {
try {
- PBEKeySpec keyspec = new PBEKeySpec(password.toCharArray(), salt, 65536, 128);
+ PBEKeySpec keyspec = new PBEKeySpec(password.toCharArray(),
+ salt,
+ 65536,
+ 128);
SecretKey tmpkey = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256").generateSecret(keyspec);
return new SecretKeySpec(tmpkey.getEncoded(), "AES");
} catch (Exception e) {
}
/**
- * Inits the HMAC generator.
+ * Inits all the security stuff
*/
+ public void initSecurity() throws ServerException {
+ // try to get the salt and if one does not exist set one
+ if (!getSalt()) {
+ //Set the salt
+ setSalt();
+ }
+ initCrypt();
+ }
+
+ /**
+ * Inits the HMAC generator.
+ */
private void initCrypt() {
+
+ if (password == null) {
+ return;
+ }
+
try {
- SecretKeySpec key = initKey();
+ key = initKey();
password = null; // drop password
mac = Mac.getInstance("HmacSHA256");
mac.init(key);
- encryptCipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
- encryptCipher.init(Cipher.ENCRYPT_MODE, key);
- decryptCipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
- decryptCipher.init(Cipher.DECRYPT_MODE, key);
} catch (Exception e) {
e.printStackTrace();
throw new Error("Failed To Initialize Ciphers");
/*
* Builds the URL for the given request.
*/
-
private URL buildRequest(boolean isput, long sequencenumber, long maxentries) throws IOException {
String reqstring = isput ? "req=putslot" : "req=getslot";
String urlstr = baseurl + "?" + reqstring + "&seq=" + sequencenumber;
return new URL(urlstr);
}
- public void setSalt() {
+ private void setSalt() throws ServerException {
+
+ if (salt != null) {
+ // Salt already sent to server so dont set it again
+ return;
+ }
+
try {
- salt = new byte[SALT_SIZE];
- random.nextBytes(salt);
+ byte[] saltTmp = new byte[SALT_SIZE];
+ random.nextBytes(saltTmp);
+
+ for (int i = 0; i < SALT_SIZE; i++) {
+ System.out.println((int)saltTmp[i] & 255);
+ }
+
+
URL url = new URL(baseurl + "?req=setsalt");
+
+ timer.startTime();
URLConnection con = url.openConnection();
HttpURLConnection http = (HttpURLConnection) con;
+
http.setRequestMethod("POST");
- http.setFixedLengthStreamingMode(salt.length);
+ http.setFixedLengthStreamingMode(saltTmp.length);
http.setDoOutput(true);
+ http.setConnectTimeout(TIMEOUT_MILLIS);
+
+
http.connect();
+
OutputStream os = http.getOutputStream();
- os.write(salt);
+ os.write(saltTmp);
+ os.flush();
+
+ int responsecode = http.getResponseCode();
+ if (responsecode != HttpURLConnection.HTTP_OK) {
+ // TODO: Remove this print
+ System.out.println(responsecode);
+ throw new Error("Invalid response");
+ }
+
+ timer.endTime();
+
+ salt = saltTmp;
+ } catch (Exception e) {
+ // e.printStackTrace();
+ timer.endTime();
+ throw new ServerException("Failed setting salt", ServerException.TypeConnectTimeout);
+ }
+ }
+
+ private boolean getSalt() throws ServerException {
+ URL url = null;
+ URLConnection con = null;
+ HttpURLConnection http = null;
+
+ try {
+ url = new URL(baseurl + "?req=getsalt");
+ } catch (Exception e) {
+ // e.printStackTrace();
+ throw new Error("getSlot failed");
+ }
+ try {
+
+ timer.startTime();
+ con = url.openConnection();
+ http = (HttpURLConnection) con;
+ http.setRequestMethod("POST");
+ http.setConnectTimeout(TIMEOUT_MILLIS);
+ http.setReadTimeout(TIMEOUT_MILLIS);
+
+
+ http.connect();
+ timer.endTime();
+ } catch (SocketTimeoutException e) {
+ timer.endTime();
+ throw new ServerException("getSalt failed", ServerException.TypeConnectTimeout);
+ } catch (Exception e) {
+ // e.printStackTrace();
+ throw new Error("getSlot failed");
+ }
+
+ try {
+
+ timer.startTime();
+
int responsecode = http.getResponseCode();
if (responsecode != HttpURLConnection.HTTP_OK) {
// TODO: Remove this print
// System.out.println(responsecode);
throw new Error("Invalid response");
}
+
+ InputStream is = http.getInputStream();
+ if (is.available() > 0) {
+ DataInputStream dis = new DataInputStream(is);
+ int salt_length = dis.readInt();
+ byte [] tmp = new byte[salt_length];
+ dis.readFully(tmp);
+ salt = tmp;
+ timer.endTime();
+
+ return true;
+ } else {
+ timer.endTime();
+
+ return false;
+ }
+ } catch (SocketTimeoutException e) {
+ timer.endTime();
+
+ throw new ServerException("getSalt failed", ServerException.TypeInputTimeout);
+ } catch (Exception e) {
+ // e.printStackTrace();
+ throw new Error("getSlot failed");
+ }
+ }
+
+ private byte[] createIV(long machineId, long localSequenceNumber) {
+ ByteBuffer buffer = ByteBuffer.allocate(IV_SIZE);
+ buffer.putLong(machineId);
+ buffer.putLong(localSequenceNumber);
+ return buffer.array();
+
+ }
+
+ private byte[] encryptSlotAndPrependIV(byte[] rawData, byte[] ivBytes) {
+ try {
+ IvParameterSpec ivSpec = new IvParameterSpec(ivBytes);
+ Cipher cipher = Cipher.getInstance("AES/CTR/PKCS5Padding");
+ cipher.init(Cipher.ENCRYPT_MODE, key, ivSpec);
+
+ byte[] encryptedBytes = cipher.doFinal(rawData);
+
+ byte[] bytes = new byte[encryptedBytes.length + IV_SIZE];
+ System.arraycopy(ivBytes, 0, bytes, 0, ivBytes.length);
+ System.arraycopy(encryptedBytes, 0, bytes, IV_SIZE, encryptedBytes.length);
+
+ return bytes;
+
} catch (Exception e) {
e.printStackTrace();
- throw new Error("Failed setting salt");
+ throw new Error("Failed To Encrypt");
}
- initCrypt();
}
- private void getSalt() throws Exception {
- URL url = new URL(baseurl + "?req=getsalt");
- URLConnection con = url.openConnection();
- HttpURLConnection http = (HttpURLConnection) con;
- http.setRequestMethod("POST");
- http.connect();
- InputStream is = http.getInputStream();
- DataInputStream dis = new DataInputStream(is);
- int salt_length = dis.readInt();
- byte [] tmp = new byte[salt_length];
- dis.readFully(tmp);
- salt = tmp;
+ private byte[] stripIVAndDecryptSlot(byte[] rawData) {
+ try {
+ byte[] ivBytes = new byte[IV_SIZE];
+ byte[] encryptedBytes = new byte[rawData.length - IV_SIZE];
+ System.arraycopy(rawData, 0, ivBytes, 0, IV_SIZE);
+ System.arraycopy(rawData, IV_SIZE, encryptedBytes, 0 , encryptedBytes.length);
+
+ IvParameterSpec ivSpec = new IvParameterSpec(ivBytes);
+
+ Cipher cipher = Cipher.getInstance("AES/CTR/PKCS5Padding");
+ cipher.init(Cipher.DECRYPT_MODE, key, ivSpec);
+
+ return cipher.doFinal(encryptedBytes);
+
+ } catch (Exception e) {
+ e.printStackTrace();
+ throw new Error("Failed To Decrypt");
+ }
}
+
/*
* API for putting a slot into the queue. Returns null on success.
* On failure, the server will send slots with newer sequence
* numbers.
*/
+ public Slot[] putSlot(Slot slot, int max) throws ServerException {
+ URL url = null;
+ URLConnection con = null;
+ HttpURLConnection http = null;
- Slot[] putSlot(Slot slot, int max) {
try {
if (salt == null) {
- getSalt();
+ if (!getSalt()) {
+ throw new ServerException("putSlot failed", ServerException.TypeSalt);
+ }
initCrypt();
}
long sequencenumber = slot.getSequenceNumber();
- byte[] bytes = slot.encode(mac);
- bytes = encryptCipher.doFinal(bytes);
+ byte[] slotBytes = slot.encode(mac);
+ // slotBytes = encryptCipher.doFinal(slotBytes);
- URL url = buildRequest(true, sequencenumber, max);
- URLConnection con = url.openConnection();
- HttpURLConnection http = (HttpURLConnection) con;
+ // byte[] iVBytes = slot.getSlotCryptIV();
+
+ // byte[] bytes = new byte[slotBytes.length + IV_SIZE];
+ // System.arraycopy(iVBytes, 0, bytes, 0, iVBytes.length);
+ // System.arraycopy(slotBytes, 0, bytes, IV_SIZE, slotBytes.length);
+
+
+ byte[] bytes = encryptSlotAndPrependIV(slotBytes, slot.getSlotCryptIV());
+
+ url = buildRequest(true, sequencenumber, max);
+
+ timer.startTime();
+ con = url.openConnection();
+ http = (HttpURLConnection) con;
http.setRequestMethod("POST");
http.setFixedLengthStreamingMode(bytes.length);
http.setDoOutput(true);
+ http.setConnectTimeout(TIMEOUT_MILLIS);
+ http.setReadTimeout(TIMEOUT_MILLIS);
http.connect();
OutputStream os = http.getOutputStream();
os.write(bytes);
+ os.flush();
+
+ timer.endTime();
+
+
+ // System.out.println("Bytes Sent: " + bytes.length);
+ } catch (ServerException e) {
+ timer.endTime();
+
+ throw e;
+ } catch (SocketTimeoutException e) {
+ timer.endTime();
+
+ throw new ServerException("putSlot failed", ServerException.TypeConnectTimeout);
+ } catch (Exception e) {
+ // e.printStackTrace();
+ throw new Error("putSlot failed");
+ }
+
+
+ try {
+ timer.startTime();
InputStream is = http.getInputStream();
DataInputStream dis = new DataInputStream(is);
byte[] resptype = new byte[7];
dis.readFully(resptype);
- if (Arrays.equals(resptype, "getslot".getBytes()))
+ timer.endTime();
+
+ if (Arrays.equals(resptype, "getslot".getBytes())) {
return processSlots(dis);
- else if (Arrays.equals(resptype, "putslot".getBytes()))
+ } else if (Arrays.equals(resptype, "putslot".getBytes())) {
return null;
- else
+ } else
throw new Error("Bad response to putslot");
+
+ } catch (SocketTimeoutException e) {
+ timer.endTime();
+ throw new ServerException("putSlot failed", ServerException.TypeInputTimeout);
} catch (Exception e) {
- e.printStackTrace();
+ // e.printStackTrace();
throw new Error("putSlot failed");
}
}
* Request the server to send all slots with the given
* sequencenumber or newer.
*/
+ public Slot[] getSlots(long sequencenumber) throws ServerException {
+ URL url = null;
+ URLConnection con = null;
+ HttpURLConnection http = null;
- Slot[] getSlots(long sequencenumber) {
try {
if (salt == null) {
- getSalt();
+ if (!getSalt()) {
+ throw new ServerException("getSlots failed", ServerException.TypeSalt);
+ }
initCrypt();
}
- URL url = buildRequest(false, sequencenumber, 0);
- URLConnection con = url.openConnection();
- HttpURLConnection http = (HttpURLConnection) con;
+ url = buildRequest(false, sequencenumber, 0);
+ timer.startTime();
+ con = url.openConnection();
+ http = (HttpURLConnection) con;
http.setRequestMethod("POST");
+ http.setConnectTimeout(TIMEOUT_MILLIS);
+ http.setReadTimeout(TIMEOUT_MILLIS);
+
+
+
http.connect();
- InputStream is = http.getInputStream();
+ timer.endTime();
- DataInputStream dis = new DataInputStream(is);
+ } catch (SocketTimeoutException e) {
+ timer.endTime();
+ throw new ServerException("getSlots failed", ServerException.TypeConnectTimeout);
+ } catch (ServerException e) {
+ timer.endTime();
+
+ throw e;
+ } catch (Exception e) {
+ // e.printStackTrace();
+ throw new Error("getSlots failed");
+ }
+
+ try {
+
+ timer.startTime();
+ InputStream is = http.getInputStream();
+ DataInputStream dis = new DataInputStream(is);
byte[] resptype = new byte[7];
+
dis.readFully(resptype);
+ timer.endTime();
+
if (!Arrays.equals(resptype, "getslot".getBytes()))
throw new Error("Bad Response: " + new String(resptype));
- else
- return processSlots(dis);
+
+ return processSlots(dis);
+ } catch (SocketTimeoutException e) {
+ timer.endTime();
+
+ throw new ServerException("getSlots failed", ServerException.TypeInputTimeout);
} catch (Exception e) {
- e.printStackTrace();
+ // e.printStackTrace();
throw new Error("getSlots failed");
}
}
* Method that actually handles building Slot objects from the
* server response. Shared by both putSlot and getSlots.
*/
-
private Slot[] processSlots(DataInputStream dis) throws Exception {
int numberofslots = dis.readInt();
int[] sizesofslots = new int[numberofslots];
+
Slot[] slots = new Slot[numberofslots];
for (int i = 0; i < numberofslots; i++)
sizesofslots[i] = dis.readInt();
for (int i = 0; i < numberofslots; i++) {
- byte[] data = new byte[sizesofslots[i]];
- dis.readFully(data);
- data = decryptCipher.doFinal(data);
+ byte[] rawData = new byte[sizesofslots[i]];
+ dis.readFully(rawData);
+
+
+ // byte[] data = new byte[rawData.length - IV_SIZE];
+ // System.arraycopy(rawData, IV_SIZE, data, 0, data.length);
+
+
+ byte[] data = stripIVAndDecryptSlot(rawData);
+
+ // data = decryptCipher.doFinal(data);
slots[i] = Slot.decode(table, data, mac);
}
dis.close();
return slots;
}
+
+ public byte[] sendLocalData(byte[] sendData, long localSequenceNumber, String host, int port) {
+
+ if (salt == null) {
+ return null;
+ }
+ try {
+ System.out.println("Passing Locally");
+
+ mac.update(sendData);
+ byte[] genmac = mac.doFinal();
+ byte[] totalData = new byte[sendData.length + genmac.length];
+ System.arraycopy(sendData, 0, totalData, 0, sendData.length);
+ System.arraycopy(genmac, 0, totalData, sendData.length, genmac.length);
+
+ // Encrypt the data for sending
+ // byte[] encryptedData = encryptCipher.doFinal(totalData);
+ // byte[] encryptedData = encryptCipher.doFinal(totalData);
+ byte[] iv = createIV(table.getMachineId(), table.getLocalSequenceNumber());
+ byte[] encryptedData = encryptSlotAndPrependIV(totalData, iv);
+
+ // Open a TCP socket connection to a local device
+ Socket socket = new Socket(host, port);
+ socket.setReuseAddress(true);
+ DataOutputStream output = new DataOutputStream(socket.getOutputStream());
+ DataInputStream input = new DataInputStream(socket.getInputStream());
+
+
+ timer.startTime();
+ // Send data to output (length of data, the data)
+ output.writeInt(encryptedData.length);
+ output.write(encryptedData, 0, encryptedData.length);
+ output.flush();
+
+ int lengthOfReturnData = input.readInt();
+ byte[] returnData = new byte[lengthOfReturnData];
+ input.readFully(returnData);
+
+ timer.endTime();
+
+ // returnData = decryptCipher.doFinal(returnData);
+ returnData = stripIVAndDecryptSlot(returnData);
+ // returnData = decryptCipher.doFinal(returnData);
+
+ // We are done with this socket
+ socket.close();
+
+ mac.update(returnData, 0, returnData.length - HMAC_SIZE);
+ byte[] realmac = mac.doFinal();
+ byte[] recmac = new byte[HMAC_SIZE];
+ System.arraycopy(returnData, returnData.length - realmac.length, recmac, 0, realmac.length);
+
+ if (!Arrays.equals(recmac, realmac))
+ throw new Error("Local Error: Invalid HMAC! Potential Attack!");
+
+ byte[] returnData2 = new byte[lengthOfReturnData - recmac.length];
+ System.arraycopy(returnData, 0, returnData2, 0, returnData2.length);
+
+ return returnData2;
+ } catch (Exception e) {
+ e.printStackTrace();
+ // throw new Error("Local comms failure...");
+
+ }
+
+ return null;
+ }
+
+ private void localServerWorkerFunction() {
+
+ ServerSocket inputSocket = null;
+
+ try {
+ // Local server socket
+ inputSocket = new ServerSocket(listeningPort);
+ inputSocket.setReuseAddress(true);
+ inputSocket.setSoTimeout(TIMEOUT_MILLIS);
+ } catch (Exception e) {
+ e.printStackTrace();
+ throw new Error("Local server setup failure...");
+ }
+
+ while (!doEnd) {
+
+ try {
+ // Accept incoming socket
+ Socket socket = inputSocket.accept();
+
+ DataInputStream input = new DataInputStream(socket.getInputStream());
+ DataOutputStream output = new DataOutputStream(socket.getOutputStream());
+
+ // Get the encrypted data from the server
+ int dataSize = input.readInt();
+ byte[] readData = new byte[dataSize];
+ input.readFully(readData);
+
+ timer.endTime();
+
+ // Decrypt the data
+ // readData = decryptCipher.doFinal(readData);
+ readData = stripIVAndDecryptSlot(readData);
+
+ mac.update(readData, 0, readData.length - HMAC_SIZE);
+ byte[] genmac = mac.doFinal();
+ byte[] recmac = new byte[HMAC_SIZE];
+ System.arraycopy(readData, readData.length - recmac.length, recmac, 0, recmac.length);
+
+ if (!Arrays.equals(recmac, genmac))
+ throw new Error("Local Error: Invalid HMAC! Potential Attack!");
+
+ byte[] returnData = new byte[readData.length - recmac.length];
+ System.arraycopy(readData, 0, returnData, 0, returnData.length);
+
+ // Process the data
+ // byte[] sendData = table.acceptDataFromLocal(readData);
+ byte[] sendData = table.acceptDataFromLocal(returnData);
+
+
+ mac.update(sendData);
+ byte[] realmac = mac.doFinal();
+ byte[] totalData = new byte[sendData.length + realmac.length];
+ System.arraycopy(sendData, 0, totalData, 0, sendData.length);
+ System.arraycopy(realmac, 0, totalData, sendData.length, realmac.length);
+
+ // Encrypt the data for sending
+ // byte[] encryptedData = encryptCipher.doFinal(totalData);
+ byte[] iv = createIV(table.getMachineId(), table.getLocalSequenceNumber());
+ byte[] encryptedData = encryptSlotAndPrependIV(totalData, iv);
+
+
+ timer.startTime();
+ // Send data to output (length of data, the data)
+ output.writeInt(encryptedData.length);
+ output.write(encryptedData, 0, encryptedData.length);
+ output.flush();
+
+ // close the socket
+ socket.close();
+ } catch (Exception e) {
+
+ }
+ }
+
+ if (inputSocket != null) {
+ try {
+ inputSocket.close();
+ } catch (Exception e) {
+ e.printStackTrace();
+ throw new Error("Local server close failure...");
+ }
+ }
+ }
+
+ public void close() {
+ doEnd = true;
+
+ if (localServerThread != null) {
+ try {
+ localServerThread.join();
+ } catch (Exception e) {
+ e.printStackTrace();
+ throw new Error("Local Server thread join issue...");
+ }
+ }
+
+ // System.out.println("Done Closing Cloud Comm");
+ }
+
+ protected void finalize() throws Throwable {
+ try {
+ close(); // close open files
+ } finally {
+ super.finalize();
+ }
+ }
}