--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/src/main/java/ch/ethz/ssh2/crypto/cipher/BlockCipherFactory.java	Thu Dec 03 11:23:55 2015 -0800
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2006-2011 Christian Plattner. All rights reserved.
+ * Please refer to the LICENSE.txt for licensing details.
+ */
+package ch.ethz.ssh2.crypto.cipher;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Vector;
+
+/**
+ * BlockCipherFactory.
+ *
+ * @author Christian Plattner
+ * @version $Id: BlockCipherFactory.java 86 2014-04-07 14:15:18Z dkocher@sudo.ch $
+ */
+public class BlockCipherFactory {
+    private static final class CipherEntry {
+        String type;
+        int blocksize;
+        int keysize;
+        String cipherClass;
+
+        public CipherEntry(String type, int blockSize, int keySize, String cipherClass) {
+            this.type = type;
+            this.blocksize = blockSize;
+            this.keysize = keySize;
+            this.cipherClass = cipherClass;
+        }
+    }
+
+    private static final List<CipherEntry> ciphers = new ArrayList<CipherEntry>();
+
+    static {
+        // Higher priority (stronger) first
+        ciphers.add(new CipherEntry("aes256-ctr", 16, 32, "ch.ethz.ssh2.crypto.cipher.AES"));
+        ciphers.add(new CipherEntry("aes192-ctr", 16, 24, "ch.ethz.ssh2.crypto.cipher.AES"));
+        ciphers.add(new CipherEntry("aes128-ctr", 16, 16, "ch.ethz.ssh2.crypto.cipher.AES"));
+        ciphers.add(new CipherEntry("blowfish-ctr", 8, 16, "ch.ethz.ssh2.crypto.cipher.BlowFish"));
+        ciphers.add(new CipherEntry("aes256-cbc", 16, 32, "ch.ethz.ssh2.crypto.cipher.AES"));
+        ciphers.add(new CipherEntry("aes192-cbc", 16, 24, "ch.ethz.ssh2.crypto.cipher.AES"));
+        ciphers.add(new CipherEntry("aes128-cbc", 16, 16, "ch.ethz.ssh2.crypto.cipher.AES"));
+        ciphers.add(new CipherEntry("blowfish-cbc", 8, 16, "ch.ethz.ssh2.crypto.cipher.BlowFish"));
+        ciphers.add(new CipherEntry("3des-ctr", 8, 24, "ch.ethz.ssh2.crypto.cipher.DESede"));
+        ciphers.add(new CipherEntry("3des-cbc", 8, 24, "ch.ethz.ssh2.crypto.cipher.DESede"));
+    }
+
+    public static String[] getDefaultCipherList() {
+        List<String> list = new ArrayList<String>(ciphers.size());
+
+        for (CipherEntry ce : ciphers) {
+            list.add(ce.type);
+        }
+
+        return list.toArray(new String[ciphers.size()]);
+    }
+
+    public static void checkCipherList(String[] cipherCandidates) {
+        for (String cipherCandidate : cipherCandidates) {
+            getEntry(cipherCandidate);
+        }
+    }
+
+    //  @SuppressWarnings("rawtypes")
+    public static BlockCipher createCipher(String type, boolean encrypt, byte[] key, byte[] iv) {
+        try {
+            CipherEntry ce = getEntry(type);
+            Class<?> cc = Class.forName(ce.cipherClass);
+            BlockCipher bc = (BlockCipher) cc.newInstance();
+
+            if (type.endsWith("-cbc")) {
+                bc.init(encrypt, key);
+                return new CBCMode(bc, iv, encrypt);
+            }
+            else if (type.endsWith("-ctr")) {
+                bc.init(true, key);
+                return new CTRMode(bc, iv, encrypt);
+            }
+
+            throw new IllegalArgumentException("Cannot instantiate " + type);
+        }
+        catch (ClassNotFoundException e) {
+            throw new IllegalArgumentException("Cannot instantiate " + type, e);
+        }
+        catch (InstantiationException e) {
+            throw new IllegalArgumentException("Cannot instantiate " + type, e);
+        }
+        catch (IllegalAccessException e) {
+            throw new IllegalArgumentException("Cannot instantiate " + type, e);
+        }
+    }
+
+    private static CipherEntry getEntry(String type) {
+        for (CipherEntry ce : ciphers) {
+            if (ce.type.equals(type)) {
+                return ce;
+            }
+        }
+
+        throw new IllegalArgumentException("Unkown algorithm " + type);
+    }
+
+    public static int getBlockSize(String type) {
+        CipherEntry ce = getEntry(type);
+        return ce.blocksize;
+    }
+
+    public static int getKeySize(String type) {
+        CipherEntry ce = getEntry(type);
+        return ce.keysize;
+    }
+}