Using GPG to encrypt messages (like email)

I wanted to email phrack, but their contact info specifies the use of a public key/GPG. So I wanted to send them a GPG-encrypted/signed email message! Here’s a guide on encrypting/signing arbitrary text content with GPG.

I downloaded their public key as phrack.asc

https://phrack.org/contact

This is for staff(at)phrack[DOT]org

encrypting a message for them

then i imported the public key: gpg --import phrack.asc

then make a message like email.txt and then:

gpg --encrypt --armor -r staff@phrack.org email.txt

then copy its contents and paste into the body of email (or attach it). i just pasted into claws mails as plaintext

don’t forget to sign it! signing it is just letting them know it actually came from you, they’ll be able to view it without knowing your public key. like this:

gpg --encrypt --sign --armor --local-user someodd@pm.me -r staff@phrack.org email.txt

keep your key updated!

if you need to update your key (you should keep it updated!) make a message that’s signed.

first create the new key with gpg --full-generate-key or whatever. then write a message like this key-update.txt:

I, someodd@pm.me, am transitioning to a new PGP key. My new key fingerprint is:

[NEW_KEY_FINGERPRINT]

This message is signed with my old PGP key to prove my identity.

sign the statement with this:

gpg --sign --armor --local-user someidhere key-update.txt

This creates a signed file, key-update.txt.asc, that anyone can verify using your old public key. then others can:

gpg --verify key-update.txt.asc
gpg --import new-public-key.asc

Don’t forget to revoke the old key if not used:

gpg --output revoke.asc --gen-revoke <OldKeyID>

I’m not going to get into keyservers.

Set key expiration.

Original content in gopherspace: gopher://gopher.someodd.zip:70/0/phlog/gpg_messages.gopher.txt