Key Length issue about encrypt

[leocavalcante]

Hi @NTMS2017
This is a constraint of the algorithm: https://en.wikipedia.org/wiki/Advanced_Encryption_Standard
Keys must be 128, 192 or 256 bits, exactly this sizes, it's not a range.

As you researched, 1 utf-8 char is 4 bytes, so a 32 char length key is equals to 32 * 4 = 128 bits.

So keys should have:

UTF-8 length	Bits
32	128
48	192
64	256

This can vary on the characters you are using

I highly recommend you to use a 256 bits key generated by a CSPRNG. PointyCastle has one, it is used for the Salts in password.

I will stick your issue to remember to add something like that in this project so you can generate cryptographic secure keys right from the terminal.

Note: You already able to do that thought /dev/urandom or RtlGenRandom.

[NTMS2017]

Thanks Leo, check all this tomorrow.