You can export a PEM-format certificate from a Mac.
Prerequisites
Become familiar with how to use Keychain Access on a Mac. For more information, see the Apple Support Web site at http://support.apple.com.
Procedure
- On the Mac, open Keychain Access.
- From the sidebar, select System Roots.
- Locate the certificate to export.
- Select .
- Select a location to save the certificate and select the Privacy Enhanced Mail (.pem) file format.