In this article, I will explain how to secure your Redis databases using SSL (Secure Sockets Layer). In production, it is a good practice to use SSL to protect the data that are moving between various computers (client applications and Redis servers). Transport Level Security (TLS) guarantees that only allowed applications/computers are connected to the database, and also that data is not viewed or altered by a middle man process.
You can secure the connections between your client applications and Redis cluster using:
In this article, I will focus on the Two-Way SSL, and using Redis Enterprise.
Prerequisites:
secretdb01, and listening on port 12000)redis-cli to run basic commandsSimple Test
Let's make sure that the database is available:
redis-cli -p 12000 -a secretdb01 INFO SERVERThis should print the Server information.
You have access to the Redis Enterprise Cluster, you go to one of the nodes to retrieve the certificate (that is a self-generated one by default).
The cluster certificate is located at: /etc/opt/redislabs/proxy_cert.pem.
You have to copy it on each client machine; note that once it is done you can use this certificate to connect using "One-Way SSL", but not the purpose of this article.
In my demonstration I am using Docker and copy the certificate using this command from my host:
docker cp redis-node1:/etc/opt/redislabs/proxy_cert.pem ./certificatesUsing the Two-Way SSL you need to have a certificate for the client that will be used by Redis database proxy to trust the client.
In this article I will use a self-signed certificate using OpenSSL, in this example, we are creating a certificate for an application named app_001.
You can create as many certificates as you want, or reuse this one for all servers/applications.
Open a terminal and run the following commands:
openssl req \
-nodes \
-newkey rsa:2048 \
-keyout client_key_app_001.pem \
-x509 \
-days 36500 \
-out client_cert_app_001.pem
This command generate a new client key (client_key_001.pem) and certificate (client_cert_001.pem) with no passphrase.
The next step is to take the certificate and add it to the database you want to protect.
Let's copy the certificate and paste it into the Redis Enterprise Web Console.
Copy the certificate in your clipboard:
Mac:
pbcopy < client_cert_app_001.pemLinux:
xclip -sel clip < client_cert_app_001.pemWindows:
clip < client_cert_app_001.pemGo to the Redis Enterprise Admin Web Console and enable TLS on your database:
The database is now protected, and it is mandatory to use the SSL certificate to connect to it.
redis-cli -p 12000 -a secretdb01 INFO SERVER
(error) ERR unencrypted connection is prohibitedIn all following examples, I am using a "self-signed" certificate, so I do not check the validity of the hostname. You should adapt the connections/TLS information based on your certificate configuration.
To connect to a SSL protected database using redis-cli you have to use stunnel.
Create a stunnel.conf file with the following content:
cert = /path_to/certificates/client_cert_app_001.pem
key = /path_to/certificates/client_key_app_001.pem
cafile = /path_to/certificates/proxy_cert.pem
client = yes
[redislabs]
accept = 127.0.0.1:6380
connect = 127.0.0.1:12000
Start stunnel using the command
stunnel ./stunnel.confThis will start a process that listen to port 6380 and used as a proxy to the Redis Enterprise database on port 12000.
redis-cli -p 6380 -a secretdb01 INFO SERVERUsing Python, you have to set the SSL connection parameters:
#!/usr/local/bin/python3
import redis
import pprint
try:
r = redis.StrictRedis(
password='secretdb01',
decode_responses=True,
host='localhost',
port=12000,
ssl=True,
ssl_keyfile='./client_key_app_001.pem',
ssl_certfile='./client_cert_app_001.pem',
ssl_cert_reqs='required',
ssl_ca_certs='./proxy_cert.pem',
)
info = r.info()
pprint.pprint(info)
except Exception as err:
print("Error connecting to Redis: {}".format(err))For Node Redis, use the TLS library to configure the client connection:
import { createClient } from 'redis';
import tls from 'tls';
import fs from 'fs';
const ssl = {
key: fs.readFileSync(
'../certificates/client_key_app_001.pem',
{encoding: 'ascii'},
),
cert: fs.readFileSync(
'../certificates/client_cert_app_001.pem',
{encoding: 'ascii'},
),
ca: [fs.readFileSync('../certificates/proxy_cert.pem', {encoding: 'ascii'})],
checkServerIdentity: () => {
return null;
},
};
const client = redis.createClient({
// replace with your connection string
url: 'rediss://localhost:12000',
socket: {
tls: true,
key: ssl.key,
cert: ssl.cert,
ca: ssl.ca,
},
});
client.info('SERVER', function (err, reply) {
console.log(reply);
});
await client.connect();More information in the documentation "Using Redis with Node.js".
In Java, to be able to connect using SSL, you have to install all the certificates in the Java environment using the keytool utility.
Create a keystore file that stores the key and certificate you have created earlier:
openssl pkcs12 -export \
-in ./client_cert_app_001.pem \
-inkey ./client_key_app_001.pem \
-out client-keystore.p12 \
-name "APP_01_P12"As you can see the keystore is used to store the credentials associated with you client; it will be used later with the -javax.net.ssl.keyStore system property in the Java application.
In addition to the keys tore, you also have to create a trust store, that is used to store other credentials for example in our case the redis cluster certificate.
Create a trust store file and add the Redis cluster certificate to it
keytool -genkey \
-dname "cn=CLIENT_APP_01" \
-alias truststorekey \
-keyalg RSA \
-keystore ./client-truststore.p12 \
-keypass secret
-storepass secret
-storetype pkcs12keytool -import \
-keystore ./client-truststore.p12 \
-file ./proxy_cert.pem \
-alias redis-cluster-crtThe trustore will be used later with the -javax.net.ssl.trustStore system property in the Java application.
You can now run the Java application with the following environment variables:
java -Djavax.net.ssl.keyStore=/path_to/certificates/java/client-keystore.p12 \
-Djavax.net.ssl.keyStorePassword=secret \
-Djavax.net.ssl.trustStore=/path_to/certificates/java/client-truststore.p12 \
-Djavax.net.ssl.trustStorePassword=secret \
-jar MyApp.jarFor this example and simplicity, I will hard code these property in the Java code itself:
import redis.clients.jedis.Jedis;
import java.net.URI;
public class SSLTest {
public static void main(String[] args) {
System.setProperty("javax.net.ssl.keyStore", "/path_to/certificates/client-keystore.p12");
System.setProperty("javax.net.ssl.keyStorePassword", "secret");
System.setProperty("javax.net.ssl.trustStore","/path_to/certificates/client-truststore.p12");
System.setProperty("javax.net.ssl.trustStorePassword","secret");
URI uri = URI.create("rediss://127.0.0.1:12000");
Jedis jedis = new Jedis(uri);
jedis.auth("secretdb01");
System.out.println(jedis.info("SERVER"));
jedis.close();
}
}rediss with 2 s to indicate that the connection should be encryptedMore information in the documentation "Using Redis with Java".
In this article, you have learned how to:
redis-cli, Python, Node and Java