AES is the industry recognised version of the Rijndael encryption
algorithm, using a 256-bit key in CBC mode.
If you enter a key that is longer than the stated key size, it will only use the key you enter upto the length of the full key size. Click the Generate button to see how long the key should be.
Keys and ciphertext that contain non-hexadecimal characters will have them removed before processing, thus newlines, spaces and other formatting characters can be used safely.
This algorithm has a bug or two - it doesn't completely decrypt or encrypt a message correctly, when decrypting a message from OpenSSL it skips the first 8 bytes, and when encrypting a message for decryption in OpenSSL, OpenSSL complains about it being a 'bad decrypt', and mutters something about a digital envelope. I believe this AES algorithm isn't creating encrypted messages according to the relevant standard.
The Generate button may be used to create a key sufficiently long to provide maximum security using a high quality pseudorandom number generator seeded from:
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