How to Store Certificate Files Securely in Spring Cloud Config Server?

Question

I have a .pfx file that I use for communicating with a web service. I load it from classpath in development environment like this:

application.yml

my-config:
  certificate: classpath:/certificate/dev/mycertificate.pfx

Service.java

SSLContext sslContext = SSLContext.getInstance(SSL_CONTEXT_PROTOCOL);
KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());

KeyStore keystore = KeyStore.getInstance("JKS");
Resource certificateResource = myConfig.getCertificate();
keystore.load(certificateResource.getInputStream(), myConfig.getCertPassword().toCharArray());
        
certificateResource.getInputStream().close()

keyManagerFactory.init(keystore, myConfig.getCertPassword().toCharArray());
sslContext.init(keyManagerFactory.getKeyManagers(), null, null);

requestContext.put(SSL_SOCKET_FACTORY, sslContext.getSocketFactory());

This works fine in development environment. The problem is, I do not want to just push the certificate resource to git repo. Also I cannot put the file inside the server because we use pivotal application service for hosting the app. So is there any way I can securely store the certificate file in the config server or anywhere else?

Thanks.

score 0 · Answer 1 · answered Jun 30 '22 at 12:43

You could put the cert into Spring Cloud Config Server. If you are using Spring Cloud Services for VMware Tanzu you can follow these instructions and store the value into CredHub through SCS.

Alternatively, you could store encrypted values in a Git backend and SCS will decrypt them for you. See instructions here. You could also store things in Vault, but Vault is not provided by the SCS for VMware Tanzu tile. You'd have to run your own Vault server. Instructions for using Vault. Both of these options, I feel, are a bit more work than using SCS's support for CredHub.

If you are trying to use only OSS Spring Cloud Config, you can do that too, but it's more work, more than I can cover here. That said, all three of these options are available there as well:

Vault and CredHub both have certificate types specifically for storing certificates. I do not believe SCS exposes these options, so you would be just storing the text representation of your certificate.

All of these options assume that you want to use Spring Cloud Config server. If you wanted an option not tied to Spring, you could use the CredHub Service Broker tile. This allows you to store items in CredHub and then present them as bound services. With it, you could create a bound service that represents your certificate, bind that to the apps that require it, and then fetch your certificate from VCAP_SERVICES like any other bound service.

The downside of this approach is that VCAP_SERVICES is an environment variable, so it's storing text only and there are limits to how much information can be stored.

How to Store Certificate Files Securely in Spring Cloud Config Server?

1 Answers1