"less" and "gpg" question

[ToddAndMargo]

Hi All,

I encrypted a file with
      gpg --symmetric foobar.txt

It created foobar.txt.gpg file as expected
and I DID NOT tell it to store the passphrase.

    $ cat foobar.txt.gpg
clearly showed a binary file.

When I ran
    $less foobar.txt.gpg

it showed me the recovered file without encryption
and DID NOT ask me for a passphrase.

When I renamed the foobar.txt.gpg to foobar.txt
and ran "less" on it, now I get a binary file.
renaming it back to gpg and now it gets decrypted
again.

HOW DID LESS figure out my key and decrypt my file?

Are there are gpg keys stored somewhere"  How do
I whack (erase) them?

Many thanks,
-T


-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Computers are like air conditioners.
They malfunction when you open windows
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[Todd Zullinger]

ToddAndMargo via users wrote:
>  Hi All,
>  
>  I encrypted a file with
>       gpg --symmetric foobar.txt
>  
>  It created foobar.txt.gpg file as expected
>  and I DID NOT tell it to store the passphrase.
>  
>     $ cat foobar.txt.gpg
>  clearly showed a binary file.
>  
>  When I ran
>     $less foobar.txt.gpg
>  
>  it showed me the recovered file without encryption
>  and DID NOT ask me for a passphrase.
>  
>  When I renamed the foobar.txt.gpg to foobar.txt
>  and ran "less" on it, now I get a binary file.
>  renaming it back to gpg and now it gets decrypted
>  again.
>  
>  HOW DID LESS figure out my key and decrypt my file? 
The LESSOPEN env variable points to the lesspipe.sh script,
which is able to do things like running gpg -d for files
matching .gpg files and sending the output to less.  It does
the same for tar files, so that less some.tar produces a
list of the files in some.tar.  And so on for many other
file types.

>  Are there are gpg keys stored somewhere"  How do
>  I whack (erase) them? 
The gpg-agent caches passphrases, I believe the default TTL
is 2 hours.  You can force that cache to be cleared if
that's the cause.  I think that's:

    gpg-connect-agent reloadagent /bye

but I haven't looked at the docs lately to confirm that.

-- 
Todd

[ToddAndMargo]

On 3/19/21 11:53 AM, Todd Zullinger wrote:
>  ToddAndMargo via users wrote:
> > Hi All,
> >
> > I encrypted a file with
> >       gpg --symmetric foobar.txt
> >
> > It created foobar.txt.gpg file as expected
> > and I DID NOT tell it to store the passphrase.
> >
> >     $ cat foobar.txt.gpg
> > clearly showed a binary file.
> >
> > When I ran
> >     $less foobar.txt.gpg
> >
> > it showed me the recovered file without encryption
> > and DID NOT ask me for a passphrase.
> >
> > When I renamed the foobar.txt.gpg to foobar.txt
> > and ran "less" on it, now I get a binary file.
> > renaming it back to gpg and now it gets decrypted
> > again.
> >
> > HOW DID LESS figure out my key and decrypt my file?
>  
>  The LESSOPEN env variable points to the lesspipe.sh script,
>  which is able to do things like running gpg -d for files
>  matching .gpg files and sending the output to less.  It does
>  the same for tar files, so that less some.tar produces a
>  list of the files in some.tar.  And so on for many other
>  file types.
>  
> > Are there are gpg keys stored somewhere"  How do
> > I whack (erase) them?
>  
>  The gpg-agent caches passphrases, I believe the default TTL
>  is 2 hours.  You can force that cache to be cleared if
>  that's the cause.  I think that's:
>  
>       gpg-connect-agent reloadagent /bye
>  
>  but I haven't looked at the docs lately to confirm that. 

That explains it.  Thank you!

[Markus Schönhaber]

19.03.21, 19:19 +0100, ToddAndMargo via users:

>  I encrypted a file with
>        gpg --symmetric foobar.txt
>  
>  It created foobar.txt.gpg file as expected
>  and I DID NOT tell it to store the passphrase.
>  
>      $ cat foobar.txt.gpg
>  clearly showed a binary file.
>  
>  When I ran
>      $less foobar.txt.gpg
>  
>  it showed me the recovered file without encryption
>  and DID NOT ask me for a passphrase.
>  
>  When I renamed the foobar.txt.gpg to foobar.txt
>  and ran "less" on it, now I get a binary file.
>  renaming it back to gpg and now it gets decrypted
>  again.
>  
>  HOW DID LESS figure out my key and decrypt my file? 
It didn't. Your gpg agent (likely gnome-keyring-daemon or similar) told
it the passphrase.

less uses
/usr/bin/lesspipe.sh
for pre-processing the files it is told to open.

-- 
Regards
  mks