Secured Socket Layer (SSL) Configuration for Tomcat

Introduction

Secured Socket Layer (SSL) is the cryptography protocol to provide message security over the Internet. It works on the notion of Private and Public keys and messages are encrypted before sending it over the network. To configure SSL on Tomcat, we need a digital certificate that can be created using Java keytool for the development environment. For the production environment, you should get the digital certificate from SSL certificate providers, for example, Verisign, Entrust, Lets’ Encrypt.

Creating SSL Certificate

Follow the below steps to create your own digital certificate.

$ keytool -genkey -alias tomcat -keyalg RSA -keystore mycertificate.cert
Enter keystore password:
Re-enter new password:
What is your first and last name?
[Unknown]:  Pankaj Kumar
What is the name of your organizational unit?
[Unknown]:  Dev
What is the name of your organization?
[Unknown]:  JournalDev
What is the name of your City or Locality?
[Unknown]:  Bangalore
What is the name of your State or Province?
[Unknown]:  Karnataka
What is the two-letter country code for this unit?
[Unknown]:  IN
Is CN=Pankaj Kumar, OU=Dev, O=JournalDev, L=Bangalore, ST=Karnataka, C=IN correct?
[no]:  Yes
Enter key password for 
(RETURN if same as keystore password):
Re-enter new password:
$ ls
mycertificate.cert

I have used the password “changeit” for Keystore and key but you can use whatever you want. Now our digital certificate is ready, and the next step is to enable HTTPS communication port in Tomcat and set it to use our digital certificate for providing SSL support.

Tomcat HTTPS Configuration

To enable SSL, open the Tomcat_Installation/conf/server.xml file and uncomment the following line:

<Connector port="8443" maxHttpHeaderSize="8192"
           maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
           enableLookups="false" disableUploadTimeout="true"
           acceptCount="100" scheme="https" secure="true"
           keystoreFile="/Users/Pankaj/tomcat/conf/mycertificate.cert"
           clientAuth="false" sslProtocol="TLS" />

To avoid any misplacement of the certificate, I have put it in the Tomcat conf directory. Now restart Tomcat and try to access any web application over HTTPS with port 8443.

Tomcat Redirect HTTP to HTTPS

So we can access any web application on both HTTP and HTTPS ports. We can set up Tomcat to redirect all HTTP requests to the HTTPS port with some configurations.

In TomcatInstallation/conf/server.xml, for the HTTP Connector, set the redirect port to the HTTPS connector port. It will look somewhat like this:

<!-- Define a non-SSL HTTP/1.1 Connector on port 8080 -->
<Connector port="8090" maxHttpHeaderSize="8192"
           maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
           enableLookups="false" redirectPort="8443" acceptCount="100"
           connectionTimeout="20000" disableUploadTimeout="true" />

In TomcatInstallation/conf/web.xml, add the below configuration but make sure to add it after all the servlet-mapping tags:

<!-- added by Pankaj for automatic redirect from HTTP to HTTPS -->
<security-constraint>
    <web-resource-collection>
        <web-resource-name>Entire Application</web-resource-name>
        <url-pattern>/*</url-pattern>
    </web-resource-collection>
    <user-data-constraint>
        <transport-guarantee>CONFIDENTIAL</transport-guarantee>
    </user-data-constraint>
</security-constraint>

Restart Tomcat now, and all the HTTP requests will automatically be redirected to HTTPS, i.e., https://localhost:8080/axis2 will be automatically redirected to https://localhost:8443/axis2.

Note: If you don’t want to provide ports in the URLs, then use 80 for HTTP and 443 for HTTPS. In that case, you can skip the first step to automatically redirect HTTP requests to HTTPS because it will automatically pick the default port 443. That's it! I hope this guide about Secured Socket Layer (SSL) Configuration for Tomcat helped you.