docker-tls-setup

#
# Docker certificates
#
# IMPORTANT: before executing this script set a HOST environment variable to you machine (i.ex. external ip address which
# will be used for docker clients)
# For more info visit: https://docs.docker.com/engine/security/https/
#

sudo apt-get update
sudo apt-get install openssl

openssl genrsa -aes256 -out ca-key.pem 4096

openssl req -new -x509 -days 365 -key ca-key.pem -sha256 -out ca.pem

openssl genrsa -out server-key.pem 4096

openssl req -subj "/CN=$HOST" -sha256 -new -key server-key.pem -out server.csr

echo subjectAltName = IP:$HOST >> extfile.cnf

echo extendedKeyUsage = serverAuth >> extfile.cnf

openssl x509 -req -days 365 -sha256 -in server.csr -CA ca.pem -CAkey ca-key.pem \
  -CAcreateserial -out server-cert.pem -extfile extfile.cnf
  
openssl genrsa -out key.pem 4096

openssl req -subj '/CN=client' -new -key key.pem -out client.csr

echo extendedKeyUsage = clientAuth > extfile-client.cnf

openssl x509 -req -days 365 -sha256 -in client.csr -CA ca.pem -CAkey ca-key.pem \
  -CAcreateserial -out cert.pem -extfile extfile-client.cnf
  
rm -v client.csr server.csr extfile.cnf extfile-client.cnf

chmod -v 0400 ca-key.pem key.pem server-key.pem

chmod -v 0444 ca.pem server-cert.pem cert.pem

#
# Visit: https://docs.docker.com/config/daemon/#use-the-hosts-key-in-daemon-json-with-systemd
#
# dockerd --tlsverify --tlscacert=ca.pem --tlscert=server-cert.pem --tlskey=server-key.pem -H=0.0.0.0:2376

sudo mkdir /etc/systemd/system/docker.service.d/

touch /etc/systemd/system/docker.service.d/docker.conf

sudo bash -c 'echo -e "[Service]\nExecStart=\nExecStart=/usr/bin/dockerd" > /etc/systemd/system/docker.service.d/docker.conf'

sudo systemctl daemon-reload

echo "Copy ca.pem, cert.pem, key.pem to your local machine"