Java Android Error "too Much Data For Rsa Block"

A have an error in my Android project (RSA encryption/decryption). The encryption passes OK, but when I trying to decrypt encrypted text, yhere are an error: 'too much data for RSA

Solution 1:

Your issue is that you need to encode/decode the ciphertext (just text in your code) if you want to transport it using a textual representation (String in your case).

Try and look up base 64 encoding on this site, there should be a lot of information about it. Encode after encryption and decode before decryption. You should also specify a specific character encoding for your plaintext.

Finally, you should probably encrypt with a symmetric cipher, and encrypt the symmetric key using RSA. Otherwise you may run out of space within the RSA calculation, because a public key cannot encrypt data larger than its modulus (key size).