How to create additional permissions and use them in addon?

Hi,

For certain screens, I want to create additional permissions / authorizations, like for example, in Business Partner, only authorized user should be able to edit tax information. All users will be allowed to update other details of a Business Partner, but tax information is editable only by users having a specific authorization.

How can I create such an authorization, and how can I access them in my UI addon?

Thanks.