Once you've got premail set up, actually using encryption is easy.
You simply add commands in double parentheses to the e-mail addresses.
The encrypt-pgp
command (which can be abbreviated to
key
) adds encryption to the outgoing mail, and the
sign
command signs it.
For example, to send me encrypted mail, you'd send it to
raph@cs.berkeley.edu ((encrypt-pgp))
. You need to have
a key with this user id on your PGP public keyring, otherwise you'll
get an error message. If the user id on the key doesn't match the
e-mail address, you can specify it directly. For example, to send mail
directly to my workstation, but using the same public key as above,
use raph@kiwi.cs.berkeley.edu
((key=raph@cs.berkeley.edu))
.
Signing works much the same way. I can sign mail by adding
((sign=raph@cs.berkeley.edu))
to the outgoing address.
Actually, because I set the signuser
configuration option in
my preferences file, all I have to add is ((sign))
.
Doing both encryption and signing is just as easy. For example, to send me signed, encrypted mail, use this line:
To: raph@cs.berkeley.edu ((encrypt-pgp, sign))
Each recipient is treated separately - the double-paren commands
after an e-mail address apply to that recipient only. However, you can
add a Sign:
header field to indicate that your message is
signed for all recipients. Example:
To: vp@company, secretary@company, employees@company,
friend@outside ((encrypt-pgp))
Subject: Important announcement
Sign:
...
In this example, all recipients will get a signed message, and the message to friend@outside will be encrypted as well.