Been trying to get a CGI to decrypt an encoded, armored string sent via a post. If the string is saved to the file (say) 'file.txt' then "gpg --decrypt file.txt" from the bash shell will successfully decrypt the file, once I use the passphase 'abc123!' for the passphrase to the secret key.

However, if I try to decode this in the CGI script itself using Crypt::OpenPGP, I cannot get it to work. I've modified the code until the cows come home and most of the time I get the same error message "Symkey decrypt failed: Invalid secret key ID". Here's the relevant code snippet:

use Crypt::OpenPGP; 
use CGI; 

my $pgp = Crypt::OpenPGP->new(Compat => 'GnuPG'); 
my $cur=CGI->new(); 
my $phrase=$cur->param('phrase'); 

my ($plaintext,$valid,$sig)=$pgp->decrypt(Data => $phrase, Passphrase 
+=> "abc123!"); 
print "[message: $plaintext<br>valid: $valid<br>signature: $sig<br>err
+or: ".$pgp->errstr."]<br><br>\n";

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The last print statement returns the following:

message:
valid:
signature:
error: Symkey decrypt failed: Invalid secret key ID

And yet, if I dump the contents of the variable $phrase to the file file.txt and do gpg --decrypt file.txt from bash with passphrase abc123! to unlock the secret key it will successfully decode.

In reply to Need help decoding string in Crypt::OpenPGP by jaf0faj

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