What's a good lock box ??

[James Wilkinson]

Les Mikesell wrote:
> If you want something really simple, there is:
> vi -x filename
> It will prompt for the encryption key and keep the file
> copy encrypted.

Timothy Murphy replied:
> I actually use this for some information,
> but I've often wondered if there is any way of un-encrypting the file?
> 
> I know that one can _see_ the file OK after giving the key,
> but I don't know what I would do if a new version of vim came out
> which did not work with -x ...

A quick check suggests that if you type
:set
while in vim, then one of the values given is
key=*****
Entering
:set key=
makes vim forget the key, and any subsequent writes will be in plaintext.

Google suggests that you can run ":h encryption" to read the appropriate
help file, and that ":set key=" is the official way of making vim forget
the key.

Warning: the same help file says:
    The algorithm used is breakable. A 4 character key in about one hour,
    a 6 character key in one day (on a Pentium 133 PC). This requires
    that you know some text that must appear in the file.

I would expect that six-character key to last about one hour on a current
PC. So vim on its own would *not* count as a good lock box.

Hope this helps,

James.

-- 
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