GPG

wget https://sks-keyservers.net/sks-keyservers.netCA.pem -O /etc/ca-certificates/extracted/sks-keyservers.netCA.pem

# extract the primary key
gpg -a --export-secret-key [email protected] > secret_key
# extract the subkeys, which we will reimport later
gpg -a --export-secret-subkeys [email protected] > secret_subkeys.gpg
# *delete* the secret keys from the keyring, so only subkeys are left
$ gpg --delete-secret-keys [email protected]
Delete this key from the keyring? (y/N) y
This is a secret key! - really delete? (y/N) y
# reimport the subkeys
$ gpg --import secret_subkeys.gpg
# verify everything is in order
$ gpg --list-secret-keys
# remove the subkeys from disk
$ rm secret_subkeys.gpg

#
# This is an implementation of the Riseup OpenPGP Best Practices
# https://help.riseup.net/en/security/message-security/openpgp/best-practices
#


#-----------------------------
# default key
#-----------------------------

# The default key to sign with. If this option is not used, the default key is
# the first key found in the secret keyring

#default-key 0xD8692123C4065DEA5E0F3AB5249B39D24F25E3B6


#-----------------------------
# behavior
#-----------------------------

# Disable inclusion of the version string in ASCII armored output
no-emit-version

# Disable comment string in clear text signatures and ASCII armored messages
no-comments

# Display long key IDs
keyid-format 0xlong

# List all keys (or the specified ones) along with their fingerprints
with-fingerprint

# Display the calculated validity of user IDs during key listings
list-options show-uid-validity
verify-options show-uid-validity

# Try to use the GnuPG-Agent. With this option, GnuPG first tries to connect to
# the agent before it asks for a passphrase.
use-agent

# Set default charset
charset utf-8

#-----------------------------
# keyserver
#-----------------------------

# This is the server that --recv-keys, --send-keys, and --search-keys will
# communicate with to receive keys from, send keys to, and search for keys on
keyserver hkps://hkps.pool.sks-keyservers.net

# Provide a certificate store to override the system default
# Get this from https://sks-keyservers.net/sks-keyservers.netCA.pem
keyserver-options ca-cert-file=/path/to/CA/sks-keyservers.netCA.pem

# Set the proxy to use for HTTP and HKP keyservers - default to the standard
# local Tor socks proxy
# It is encouraged to use Tor for improved anonymity. Preferrably use either a
# dedicated SOCKSPort for GnuPG and/or enable IsolateDestPort and
# IsolateDestAddr
#keyserver-options http-proxy=socks5-hostname://127.0.0.1:9050

# Don't leak DNS, see https://trac.torproject.org/projects/tor/ticket/2846
keyserver-options no-try-dns-srv

# When using --refresh-keys, if the key in question has a preferred keyserver
# URL, then disable use of that preferred keyserver to refresh the key from
keyserver-options no-honor-keyserver-url

# When searching for a key with --search-keys, include keys that are marked on
# the keyserver as revoked
keyserver-options include-revoked


#-----------------------------
# algorithm and ciphers
#-----------------------------

# list of personal digest preferences. When multiple digests are supported by
# all recipients, choose the strongest one
personal-cipher-preferences AES256 AES192 AES CAST5

# list of personal digest preferences. When multiple ciphers are supported by
# all recipients, choose the strongest one
personal-digest-preferences SHA512 SHA384 SHA256 SHA224

# message digest algorithm used when signing a key
cert-digest-algo SHA512

# This preference list is used for new keys and becomes the default for
# "setpref" in the edit menu
default-preference-list SHA512 SHA384 SHA256 SHA224 AES256 AES192 AES CAST5 ZLIB BZIP2 ZIP Uncompressed