my target is to encrypt a String with AES I am using Base64 for encryption, because AES needs a byte array as input. Moreover i want every possible Char(including chinese and german Symbols) to be stored correctly
byte[] encryptedBytes = Base64.decodeBase64 ("some input");
System.out.println(new Base64().encodeToString(encryptedBytes));
I thought "some input" should be printed. Instead "someinpu" is printed. It is impossible for me to use sun.misc.* Instead i am using apache.commons.codec
Does someone has a clue what's going wrong?
2 Answers
Yes - "some input" isn't a valid base64 encoded string.
The idea of base64 is that you encode binary data into text. You then decode that text data to a byte array. You can't just decode any arbitrary text as if it were a complete base64 message any more than you can try to decode an mp3 as a jpeg image.
Encrypting a string should be this process:
- Encode the string to binary data, e.g. using UTF-8 (
text.getBytes("UTF-8")) - Encrypt the binary data using AES
- Encode the cyphertext using Base64 to get text
Decryption is then a matter of:
- Decode the base64 text to the binary cyphertext
- Decrypt the cyphertext to get the binary plaintext
- Decode the binary plaintext into a string using the same encoding as the first step above, e.g.
new String(bytes, "UTF-8")
You cannot use Base64 to turn arbitrary text into bytes; that's not what it's designed to do.
Instead, you should use UTF8:
byte[] plainTextBytes = inputString.getBytes("UTF8");
String output = new String(plainTextBytes, "UTF8");
