--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/src/main/java/ch/ethz/ssh2/crypto/Base64.java	Thu Dec 03 11:23:55 2015 -0800
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2006-2011 Christian Plattner. All rights reserved.
+ * Please refer to the LICENSE.txt for licensing details.
+ */
+package ch.ethz.ssh2.crypto;
+
+import java.io.CharArrayWriter;
+import java.io.IOException;
+
+/**
+ * Basic Base64 Support.
+ *
+ * @author Christian Plattner
+ * @version 2.50, 03/15/10
+ */
+public class Base64 {
+    static final char[] alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".toCharArray();
+
+    public static char[] encode(byte[] content) {
+        CharArrayWriter cw = new CharArrayWriter((4 * content.length) / 3);
+        int idx = 0;
+        int x = 0;
+
+        for (int i = 0; i < content.length; i++) {
+            if (idx == 0)
+                x = (content[i] & 0xff) << 16;
+            else if (idx == 1)
+                x = x | ((content[i] & 0xff) << 8);
+            else
+                x = x | (content[i] & 0xff);
+
+            idx++;
+
+            if (idx == 3) {
+                cw.write(alphabet[x >> 18]);
+                cw.write(alphabet[(x >> 12) & 0x3f]);
+                cw.write(alphabet[(x >> 6) & 0x3f]);
+                cw.write(alphabet[x & 0x3f]);
+                idx = 0;
+            }
+        }
+
+        if (idx == 1) {
+            cw.write(alphabet[x >> 18]);
+            cw.write(alphabet[(x >> 12) & 0x3f]);
+            cw.write('=');
+            cw.write('=');
+        }
+
+        if (idx == 2) {
+            cw.write(alphabet[x >> 18]);
+            cw.write(alphabet[(x >> 12) & 0x3f]);
+            cw.write(alphabet[(x >> 6) & 0x3f]);
+            cw.write('=');
+        }
+
+        return cw.toCharArray();
+    }
+
+    public static byte[] decode(char[] message) throws IOException {
+        byte buff[] = new byte[4];
+        byte dest[] = new byte[message.length];
+        int bpos = 0;
+        int destpos = 0;
+
+        for (int i = 0; i < message.length; i++) {
+            int c = message[i];
+
+            if ((c == '\n') || (c == '\r') || (c == ' ') || (c == '\t'))
+                continue;
+
+            if ((c >= 'A') && (c <= 'Z')) {
+                buff[bpos++] = (byte)(c - 'A');
+            }
+            else if ((c >= 'a') && (c <= 'z')) {
+                buff[bpos++] = (byte)((c - 'a') + 26);
+            }
+            else if ((c >= '0') && (c <= '9')) {
+                buff[bpos++] = (byte)((c - '0') + 52);
+            }
+            else if (c == '+') {
+                buff[bpos++] = 62;
+            }
+            else if (c == '/') {
+                buff[bpos++] = 63;
+            }
+            else if (c == '=') {
+                buff[bpos++] = 64;
+            }
+            else {
+                throw new IOException("Illegal char in base64 code.");
+            }
+
+            if (bpos == 4) {
+                bpos = 0;
+
+                if (buff[0] == 64)
+                    break;
+
+                if (buff[1] == 64)
+                    throw new IOException("Unexpected '=' in base64 code.");
+
+                if (buff[2] == 64) {
+                    int v = (((buff[0] & 0x3f) << 6) | ((buff[1] & 0x3f)));
+                    dest[destpos++] = (byte)(v >> 4);
+                    break;
+                }
+                else if (buff[3] == 64) {
+                    int v = (((buff[0] & 0x3f) << 12) | ((buff[1] & 0x3f) << 6) | ((buff[2] & 0x3f)));
+                    dest[destpos++] = (byte)(v >> 10);
+                    dest[destpos++] = (byte)(v >> 2);
+                    break;
+                }
+                else {
+                    int v = (((buff[0] & 0x3f) << 18) | ((buff[1] & 0x3f) << 12) | ((buff[2] & 0x3f) << 6) | ((buff[3] & 0x3f)));
+                    dest[destpos++] = (byte)(v >> 16);
+                    dest[destpos++] = (byte)(v >> 8);
+                    dest[destpos++] = (byte)(v);
+                }
+            }
+        }
+
+        byte[] res = new byte[destpos];
+        System.arraycopy(dest, 0, res, 0, destpos);
+        return res;
+    }
+}