SSH using GPG on Ubuntu 17.10

setup.sh

cat > ~/.gnupg/gpg-agent.conf <<EOF
default-cache-ttl 600
max-cache-ttl 7200
enable-ssh-support
EOF

gpgconf --kill gpg-agent
gpg-connect-agent reloadagent /bye

# man gpg-agent
cat >> ~/.bashrc <<EOF

unset SSH_AGENT_PID
if [ "${gnupg_SSH_AUTH_SOCK_by:-0}" -ne $$ ]; then
  export SSH_AUTH_SOCK="$(gpgconf --list-dirs agent-ssh-socket)"
fi
EOF

gpg-connect-agent updatestartuptty /bye