byte[] plainText = text.getBytes();
for(int i=0;i<plainText.length;i+=117) {
SshPublicKey pk = getPublicKey(username);
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.ENCRYPT_MODE, pk.getPublicKey());
byte[] ctext = cipher.doFinal(plainText, i, (plainText.length - i > 117 ? 117 : plainText.length - i));
String section = new String(Base64.encode(ctext), "US-ASCII");
cipherText += section + "\n";