Hey, I m developing a JNI shared library which uses AES256 CFB mode to encrypt some data using libgcrypt and then passing the encrypted the data back into java app for further processing.
However, when I try to decrypt the data by passing it again to the shared library I can no longer get the original plain text back. It seems that if I encrypted and decrypted the same data without passing it back to the Java app I would get the original plain text back.
I was thinking that it was the conversion of the char buffer that I used to store the encrypted data to a NewStringUTF() (ie env->NewStringUTF(buf)) to send back to the java that was causing the issue so is there away to get/convert the output of the encrypted data to ascii or if there was some other work around?
Many thanks, Foo
Why are you using JNI and external libraries just to encrypt a string? Use Java's built-in javax.crypto.Cipher class.
However, regarding your actual question, you should be passing the data as a byte array, not a string. Ciphers operate on bytes, not abstract Unicode codepoints.