Server/client mutual authentication

Overview

The nShield Web Services Key Storage Provider can only communicate securely with a Web Services server if the following certificates are installed:

The Web Services server’s CA certificate.
An appropriate client certificate (with each client using its own client certificate).
Any intermediate CA certificates that are to be used to form a complete chain to verify the client certificate on the Web Services server.

See the nShield Web Services Option Pack User Guide for further information concerning server/client authentication, as well as for important security guidance.

Installing certificates

The following guidance should be followed when installing certificates:

Install the Web Services server’s CA certificate into the Root store.
Below is an example of how you can do this using certutil.exe.
1. Add a CA certificate to the Root store
  certutil.exe -addstore Root <ca_certificate.pem>
2. Check that the certificate has been installed:
  certutil.exe -store Root
Install any intermediate CA certificates for the client certificate.
Below is an example of how you can do this by using certutil.exe to load the client certificate’s intermediate certificates into the CA certificate store:
```
certutil.exe -addstore CA <intermediate_ca_certificate.pem>
```
Install the client certificate and its private key. This should be a PFX file that contains a single certificate and the associated private key.

The PFX must not contain the full certificate chain.

For example, to install the PFX file in the Local Machine’s certificate store
```
certutil.exe -p <password> -importPFX [certificatestorename] <client-cert.pfx>
```
or to install the PFX file into the Current User’s certificate store
```
certutil.exe -p <password> -importPFX -user [certificatestorename] <client-cert.pfx>
```

To find the thumbprint of a certificate, use certutil.exe to view the certificate’s properties, then select the Details tab and scroll down to the Thumbprint field. For example, to view thumbprints in My store.

certutil.exe -viewstore My

PowerShell can also be used to see the thumbprint on a list. In this example store is My and store type is LocalMachine.

Get-ChildItem -Path Cert:LocalMachine\My

If necessary, update client_cert_thumbprint within cngwebservices.cfg with the changed thumbprint (see Configuring the provider for further information).