To begin using GnuPG, you must first generate
a new keypair: a public key and a private key.
To generate a keypair, at a shell prompt, type the following command:
Since you work with your user account most frequently, you should
perform this action while logged in to your user account (and not as
root).
You will see an introductory screen, with key options, including one
recommended option (the default), similar to the following:
gpg (GnuPG) 1.0.1; Copyright (C) 1999 Free Software Foundation, Inc.
This program comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to redistribute it
under certain conditions. See the file COPYING for details.
Please select what kind of key you want:
(1) DSA and ElGamal (default)
(2) DSA (sign only)
(4) ElGamal (sign and encrypt)
Your selection? |
In fact, most of the screens which require you to choose an option will
list the default option, within parentheses. You can accept the default
options simply by pressing [Enter].
In the first screen, you should accept the default option:
(1) DSA and ElGamal. This option will
allow you to create a digital signature and encrypt (and decrypt) with
two types of technologies. Type 1 and then
press [Enter].
Next, choose the key size, or how long the key should be. Generally, the
longer the key, the more resistant against attacks your messages will
be. The default size, 1024 bits, should be sufficiently strong for most
users, so press [Enter].
The next option asks you to specify how long you want your key to be
valid. Usually, the default (0 = key does not
expire) is fine. If you do choose an expiration date,
remember that anyone with whom you exchanged your public key will also
have to be informed of its expiration and supplied with a new public
key.
Your next task is to provide a user ID, with your name, your email
address, and an optional comment. When you are finished, you will be
presented with a summary of the information you entered.
Once you accept your choices, you will have to enter a passphrase.
 | Tip |
|---|
| | Like your account passwords, a good passphrase is essential for
optimal security in GnuPG. For example, mix
your passphrase with uppercase and lowercase letters, use numbers, or
punctuation marks.
|
Once you enter and verify your passphrase, your keys will be
generated. You will see a message similar to the following:
We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
+++++.+++++.++++++++....++++++++++..+++++.+++++.+++++++.+++++++
+++.++++++++++++++++++++++++++++++++++++++..........................++++ |
When the activity on the screen ceases, your new keys will be made and
placed in the directory .gnupg in your home
directory. To list your keys, use the command:
You will see something similar to the following:
/home/newuser/.gnupg/pubring.gpg
-----------------------------------------
pub 1024D/B7085C8A 2000-04-18 Your Name <you@yourisp.net>
sub 1024g/E12AF9C4 2000-04-18 |
