Verifying Sender to Signature

[Werner Koch]

On Wed, 29 Aug 2001 15:14:17 -0400, Jason Power said:

> It decrypts the file and tells me "Mary" signed it.  I can't come up with a
> way to tell this from a batch file. I want to be able to reject the file

awk(1) is your friend. Example:

eval `gpg --batch -o $tarball --status-fd 1 $datafile 2>/dev/null | awk '
    /^\[GNUPG:\] VALIDSIG/ { print "signed_by=" $3 ";" }
    /^\[GNUPG:\] SIG_ID/   { print "sig_id=" $3 "; sig_date=" $4 ";" }
     '`
echo "$pgm: signed_by=$signed_by"
echo "$pgm: sig_id=$sig_id sig_date=$sig_date"
if [ -z "$signed_by" ]; then
    echo "$pgm: $tarball has no valid signature."  >&2
    do_exit 1;
fi

This decrypts the file in $datafile , put the output into the file
named $tarball and sets some evironment variables.  The script then
goes on to print the name and fingerprints of the signer.

The script can be made much better and more secure, but you got the idea.


-- 
Werner Koch        Omnis enim res, quae dando non deficit, dum habetur
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