Using Pretty Good Privacy with GnuPG and PGP

I have installed two version of PGP software.

1. GnuPG ( Gnu Privacy Guard ) V 1.0.6 ( 2001 Free Software Foundation, Inc)
2. PGP ( Pretty Good Privacy ) V 6.5.8 ( 1999 Network Associates, Inc )

I have my keys generated with GnuPG and exported to PGP, So I can use either of them since its the same key pair. I use GnuPG mostly but keeps PGP, for any need of algorithms not supported by GnuPG.

These are some notes on setting up and using GnuPG/PGP.

Exporting GnuPG keys to PGP

public keys were staright forward.

$gpg --export -a > public.asc
$pgp -ka public.asc 

secret keys required these special options.

$gpg --export-secret-keys --no-comment -a > secret.asc
$pgp -ka secret.asc 
$rm -rf secret.asc

Using GnuPG with Pine

I am using Pine Version 4.21, but this should work for other versions as well.

Pine has a limitation of naming filters with the name of the program used. Since we use the same gpg for both encrypting and signing both filters will be named 'gpg' so you cannot select between the filters for encrypting a message or just signing.

We work around this by creating two unquely named symbolic links to gpg and use them to produce distinct filter names. The name you choose for the link will be the name of the filter ( like 'encrypt' and 'pgpsign' ).

Usually these links are created in ~/.gnupg.

1. Create symbolic links

$which gpg
/usr/local/bin/gpg

$cd ~/.gnupg

$ln -s /usr/local/bin/gpg ~/.gnupg/encrypt
$ln -s /usr/local/bin/gpg ~/.gnupg/gpgsign

2. Setup decryption of incoming encrypted mails in display-filters

Type 'S' to go to "Setup" Choose 'C' to select "Config"

Use up/down keys and space keys to go down the list of config options and locate "display-filters" and select it

Type 'A' to "Add Value"
Type in the following value and press enter.

Type 'E' to Exit Setup
Select 'Y' to save the changes, when prompted.

3. Setup encryption/signing of outgoing mails in sending-filters

Follow the same procedure as above to get into "Config" and then select the config option "sending-filters" which is immediately after "display-filters".

Type 'A' to "Add Value" for encryption.
Type in the following value and press enter.

Type 'A' again to "Add Value" for signing.
Type in the following value and press enter.

Type 'E' to Exit Setup
Select 'Y' to save the changes, when prompted.

Using PGP instead of GnuPG

The procedure described above for GnuPG with Pine, also works for PGP as well. Just replace the options in the filters with the correct ones for your PGP version.