Generate a key from the Introduction to Linux by OnWorks

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In this guide we will only discuss the very simple usage of the encryption tools and show what you will need in order to generate an encryption key and use it to encrypt data for yourself, which you can then safely store in a public place. More advanced usage directions can be found in the man pages of the various commands.

9.4.2. Generate a key

Before you can start encrypting your data, you need to create a pair of keys. The pair consists of a private and a public key. You can send the public key to correspondents, who can use it to encrypt data for you, which you decrypt with your private key. You always keep the private key, never share it with somebody else, or they will be able to decrypt data that is only destined for you. Just to make sure that no accidents happen, the private key is protected with a password. The key pair is created using this command:

willy@ubuntu:~$ gpg --key-gen

This is free software, and you are welcome to redistribute it under certain conditions. See the file COPYING for details.

gpg: directory `/home/willy.gnupg' created

gpg: new configuration file `/home/willy/.gnupg/gpg.conf' created gpg: WARNING: options in `/home/willy/.gnupg/gpg.conf' are not yet

active during this run

gpg: keyring `/home/willy/.gnupg/secring.gpg' created gpg: keyring `/home/willy/.gnupg/pubring.gpg' created Please select what kind of key you want:

(1) DSA and Elgamal (default)

(2) DSA (sign only)

(5) RSA (sign only) Your selection? 1

DSA keypair will have 1024 bits.

ELG-E keys may be between 1024 and 4096 bits long. What keysize do you want? (2048) 4096

Requested keysize is 4096 bits

Please specify how long the key should be valid.

0 = key does not expire

<n> = key expires in n days

<n>w = key expires in n weeks

<n>m = key expires in n month

<n>y = key expires in n years Key is valid for? (0) 0

Key does not expire at all Is this correct? (y/N) y

You need a user ID to identify your key; the software constructs the user ID from the Real Name, Comment and Email Address in this form:

"Heinrich Heine (Der Dichter) <[email protected]>"

Real name: Willy De Wandel Email address: [email protected] Comment: Willem

You selected this USER-ID:

"Willy De Wandel (Willem) <[email protected]>"