[kwlug-disc] encrypted files with vim

[Chris Frey]

On Mon, Sep 05, 2022 at 07:20:39PM -0400, Steve Izma wrote:
> I've seen some controversy about the strengths of the encryption
> methods, but I don't understand enough of the details to know how
> much to worry. I assume that it's generally the case that the
> longer the passphrase the better, probably minimally 12 to 15
> characters? More? Does that apply here?

The behaviour matches what I've done manually with openssl
command lines.  Only it's a lot easier with vim.  With openssl,
if I got the passphrase wrong, it gave me garbage as well.

So I assume the passphrase is manipulated until it has a suitable
key of X bit length, to feed into the cypher.  I would assume that longer
is better indeed.  Reading the openssl manpage, options like
-md and others suggest that the passphrase is turned into a
sha-256 sum, and that is used as the initial key to the cypher.
I'd be surprised if vim worked much differently.

- Chris