Docker plugin with custom ca certificates

Using docker plugin with custom trusted ca certificates.

How can i add them on docker plugin ? on config, mount point or extend plugin?

This is the case for me on rexray/cinder plugin. I want to point on custum cinder API that use TLS with custom ca certificate.

The only solution I found is to rebuild plugin with my custom CA.
But is it possible or a new feature to add mount or build a new plugin with “from”?