- In order to send encrypted messages to someone else, you need their key
- You will usually find public keys on the Internet, at keyservers or on personal or corporate websites, in ASCII format
- Let's say bob wants to import Red Hat's security public key from a keyserver. This is the key that Red Hat signs rpm packages with
- Red Hat's public key information is on their website, which includes an ASCII dump of their key
- bob is going to import Red Hat's key from the keyserver, however, which is pgp.mit.edu. He finds the key listed with a Key ID of DB42A60E
- Using the
--recv-keys option, bob gets the key directly from the server:
[bob@yohost bob]$ gpg --recv-keys --keyserver pgp.mit.edu DB42A60E
gpg: requesting key DB42A60E from pgp.mit.edu ...
gpg: key DB42A60E: public key imported
gpg: /home/bob/.gnupg/trustdb.gpg: trustdb created
gpg: Total number processed: 1
gpg: imported: 1
- bob now has the security@redhat.com key:
[bob@yohost bob]$ gpg --list-keys
/home/bob/.gnupg/pubring.gpg
----------------------------
pub 1024D/3240A1F8 2002-12-16 Bob Smith (User Bob)
sub 1024g/C16A012B 2002-12-16
pub 1024D/DB42A60E 1999-09-23 Red Hat, Inc
sub 2048g/961630A2 1999-09-23
- Now bob is going to import my key, by downloading the file from my website. http://www.linuxchick.org/pubkey.txt
- bob pulls my key down from my website:
[bob@yohost bob]$ lwp-download http://www.linuxchick.org/pubkey.txt
1.33 KB received
- Now bob has my public key in the file "pubkey.txt". He imports my key into his keyring:
[bob@yohost bob]$ gpg --import pubkey.txt
gpg: key 7776E936: public key imported
gpg: Total number processed: 1
gpg: imported: 1
- Now bob has my key, and he can encrypt things meant for me
[bob@yohost bob]$ gpg --list-keys
/home/bob/.gnupg/pubring.gpg
----------------------------
pub 1024D/3240A1F8 2002-12-16 Bob Smith (User Bob)
sub 1024g/C16A012B 2002-12-16
pub 1024D/DB42A60E 1999-09-23 Red Hat, Inc
sub 2048g/961630A2 1999-09-23
pub 1024D/7776E936 2002-10-04 Mandi Walls
sub 1024g/E0524E3E 2002-10-04