# SSL Connection Setup
# Setup for Debian-based systems
(This assumes MySQL has been installed and that sudo
is being used.)
# Generating a CA and SSL keys
Make sure OpenSSL and libraries are installed:
apt-get -y install openssl
apt-get -y install libssl-dev
Next make and enter a directory for the SSL files:
mkdir /home/ubuntu/mysqlcerts
cd /home/ubuntu/mysqlcerts
To generate keys, create a certificate authority (CA) to sign the keys (self-signed):
openssl genrsa 2048 > ca-key.pem
openssl req -new -x509 -nodes -days 3600 -key ca-key.pem -out ca.pem
The values entered at each prompt won't affect the configuration. Next create a key for the server, and sign using the CA from before:
openssl req -newkey rsa:2048 -days 3600 -nodes -keyout server-key.pem -out server-req.pem
openssl rsa -in server-key.pem -out server-key.pem
openssl x509 -req -in server-req.pem -days 3600 -CA ca.pem -CAkey ca-key.pem -set_serial 01 -out server-cert.pem
Then create a key for a client:
openssl req -newkey rsa:2048 -days 3600 -nodes -keyout client-key.pem -out client-req.pem
openssl rsa -in client-key.pem -out client-key.pem
openssl x509 -req -in client-req.pem -days 3600 -CA ca.pem -CAkey ca-key.pem -set_serial 01 -out client-cert.pem
To make sure everything was set up correctly, verify the keys:
openssl verify -CAfile ca.pem server-cert.pem client-cert.pem
# Adding the keys to MySQL
Open the MySQL configuration file (opens new window). For example:
vim /etc/mysql/mysql.conf.d/mysqld.cnf
Under the [mysqld]
section, add the following options:
ssl-ca = /home/ubuntu/mysqlcerts/ca.pem
ssl-cert = /home/ubuntu/mysqlcerts/server-cert.pem
ssl-key = /home/ubuntu/mysqlcerts/server-key.pem
Restart MySQL. For example:
service mysql restart
# Test the SSL connection
Connect in the same way, passing in the extra options ssl-ca
, ssl-cert
, and ssl-key
, using the generated client key. For example, assuming cd /home/ubuntu/mysqlcerts
:
mysql --ssl-ca=ca.pem --ssl-cert=client-cert.pem --ssl-key=client-key.pem -h 127.0.0.1 -u superman -p
After logging in, verify the connection is indeed secure:
superman@127.0.0.1 [None]> SHOW VARIABLES LIKE '%ssl%';
+---------------+-----------------------------------------+
| Variable_name | Value |
+---------------+-----------------------------------------+
| have_openssl | YES |
| have_ssl | YES |
| ssl_ca | /home/ubuntu/mysqlcerts/ca.pem |
| ssl_capath | |
| ssl_cert | /home/ubuntu/mysqlcerts/server-cert.pem |
| ssl_cipher | |
| ssl_crl | |
| ssl_crlpath | |
| ssl_key | /home/ubuntu/mysqlcerts/server-key.pem |
+---------------+-----------------------------------------+
You could also check:
superman@127.0.0.1 [None]> STATUS;
...
SSL: Cipher in use is DHE-RSA-AES256-SHA
...
# Enforcing SSL
This is via GRANT
, using REQUIRE SSL
:
GRANT ALL PRIVILEGES ON *.* TO 'superman'@'127.0.0.1' IDENTIFIED BY 'pass' REQUIRE SSL;
FLUSH PRIVILEGES;
Now, superman
must connect via SSL.
If you don't want to manage client keys, use the client key from earlier and automatically use that for all clients. Open MySQL configuration file (opens new window), for example:
vim /etc/mysql/mysql.conf.d/mysqld.cnf
Under the [client]
section, add the following options:
ssl-ca = /home/ubuntu/mysqlcerts/ca.pem
ssl-cert = /home/ubuntu/mysqlcerts/client-cert.pem
ssl-key = /home/ubuntu/mysqlcerts/client-key.pem
Now superman
only has to type the following to login via SSL:
mysql -h 127.0.0.1 -u superman -p
Connecting from another program, for example in Python, typically only requires an additional parameter to the connect function. A Python example:
import MySQLdb
ssl = {'cert': '/home/ubuntu/mysqlcerts/client-cert.pem', 'key': '/home/ubuntu/mysqlcerts/client-key.pem'}
conn = MySQLdb.connect(host='127.0.0.1', user='superman', passwd='imsoawesome', ssl=ssl)
# References and further reading:
- https://www.percona.com/blog/2013/06/22/setting-up-mysql-ssl-and-secure-connections/ (opens new window)
- https://lowendbox.com/blog/getting-started-with-mysql-over-ssl/ (opens new window)
- http://xmodulo.com/enable-ssl-mysql-server-client.html (opens new window)
- https://ubuntuforums.org/showthread.php?t=1121458 (opens new window)
# Setup for CentOS7 / RHEL7
This example assumes two servers:
- dbserver (where our database lives)
- appclient (where our applications live)
FWIW, both servers are SELinux enforcing.
# First, log on to dbserver
Create a temporary directory for creating the certificates.
mkdir /root/certs/mysql/ && cd /root/certs/mysql/
Create the server certificates
openssl genrsa 2048 > ca-key.pem
openssl req -sha1 -new -x509 -nodes -days 3650 -key ca-key.pem > ca-cert.pem
openssl req -sha1 -newkey rsa:2048 -days 730 -nodes -keyout server-key.pem > server-req.pem
openssl rsa -in server-key.pem -out server-key.pem
openssl x509 -sha1 -req -in server-req.pem -days 730 -CA ca-cert.pem -CAkey ca-key.pem -set_serial 01 > server-cert.pem
Move server certificates to /etc/pki/tls/certs/mysql/
Directory path assumes CentOS or RHEL (adjust as needed for other distros):
mkdir /etc/pki/tls/certs/mysql/
Be sure to set permissions on the folder and files. mysql needs full ownership and access.
chown -R mysql:mysql /etc/pki/tls/certs/mysql
Now configure MySQL/MariaDB
# vi /etc/my.cnf
# i
[mysqld]
bind-address=*
ssl-ca=/etc/pki/tls/certs/ca-cert.pem
ssl-cert=/etc/pki/tls/certs/server-cert.pem
ssl-key=/etc/pki/tls/certs/server-key.pem
# :wq
Then
systemctl restart mariadb
Don't forget to open your firewall to allow connections from appclient (using IP 1.2.3.4)
firewall-cmd --zone=drop --permanent --add-rich-rule 'rule family="ipv4" source address="1.2.3.4" service name="mysql" accept'
# I force everything to the drop zone. Season the above command to taste.
Now restart firewalld
service firewalld restart
Next, log in to dbserver's mysql server:
mysql -uroot -p
Issue the following to create a user for the client. note REQUIRE SSL in GRANT statement.
GRANT ALL PRIVILEGES ON *.* TO ‘iamsecure’@’appclient’ IDENTIFIED BY ‘dingdingding’ REQUIRE SSL;
FLUSH PRIVILEGES;
# quit mysql
You should still be in /root/certs/mysql from the first step. If not, cd back to it for one of the commands below.
Create the client certificates
openssl req -sha1 -newkey rsa:2048 -days 730 -nodes -keyout client-key.pem > client-req.pem
openssl rsa -in client-key.pem -out client-key.pem
openssl x509 -sha1 -req -in client-req.pem -days 730 -CA ca-cert.pem -CAkey ca-key.pem -set_serial 01 > client-cert.pem
Note: I used the same common name for both server and client certificates. YMMV.
Be sure you're still /root/certs/mysql/ for this next command
Combine server and client CA certificate into a single file:
cat server-cert.pem client-cert.pem > ca.pem
Make sure you see two certificates:
cat ca.pem
# END OF SERVER SIDE WORK FOR NOW.
Open another terminal and
ssh appclient
As before, create a permanent home for the client certificates
mkdir /etc/pki/tls/certs/mysql/
Now, place the client certificates (created on dbserver) on appclient. You can either scp them over, or just copy and paste the files one by one.
scp dbserver
# copy files from dbserver to appclient
# exit scp
Again, be sure to set permissions on the folder and files. mysql needs full ownership and access.
chown -R mysql:mysql /etc/pki/tls/certs/mysql
You should have three files, each owned by user mysql:
/etc/pki/tls/certs/mysql/ca.pem
/etc/pki/tls/certs/mysql/client-cert.pem
/etc/pki/tls/certs/mysql/client-key.pem
Now edit appclient's MariaDB/MySQL config in the [client]
section.
vi /etc/my.cnf
# i
[client]
ssl-ca=/etc/pki/tls/certs/mysql/ca.pem
ssl-cert=/etc/pki/tls/certs/mysql/client-cert.pem
ssl-key=/etc/pki/tls/certs/mysql/client-key.pem
# :wq
Restart appclient's mariadb service:
systemctl restart mariadb
# still on the client here
This should return: ssl TRUE
mysql --ssl --help
Now, log in to appclient's mysql instance
mysql -uroot -p
Should see YES to both variables below
show variables LIKE '%ssl';
have_openssl YES
have_ssl YES
Initially I saw
have_openssl NO
A quick look into mariadb.log revealed:
SSL error: Unable to get certificate from '/etc/pki/tls/certs/mysql/client-cert.pem'
The problem was that root owned client-cert.pem and the containing folder. The solution was to set ownership of /etc/pki/tls/certs/mysql/ to mysql.
chown -R mysql:mysql /etc/pki/tls/certs/mysql
Restart mariadb if needed from the step immediately above
# NOW WE ARE READY TO TEST THE SECURE CONNECTION
# We're still on appclient here
Attempt to connect to dbserver's mysql instance using the account created above.
mysql -h dbserver -u iamsecure -p
# enter password dingdingding (hopefully you changed that to something else)
With a little luck you should be logged in without error.
To confirm you are connected with SSL enabled, issue the following command from the MariaDB/MySQL prompt:
\s
That's a backslash s, aka status
That will show the status of your connection, which should look something like this:
Connection id: 4
Current database:
Current user: iamsecure@appclient
SSL: Cipher in use is DHE-RSA-AES256-GCM-SHA384
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server: MariaDB
Server version: 5.X.X-MariaDB MariaDB Server
Protocol version: 10
Connection: dbserver via TCP/IP
Server characterset: latin1
Db characterset: latin1
Client characterset: utf8
Conn. characterset: utf8
TCP port: 3306
Uptime: 42 min 13 sec
If you get permission denied errors on your connection attempt, check your GRANT statement above to make sure there aren't any stray characters or ' marks.
If you have SSL errors, go back through this guide to make sure the steps are orderly.
This worked on RHEL7 and will likely work on CentOS7, too. Cannot confirm whether these exact steps will work elsewhere.
Hope this saves someone else a little time and aggravation.