MiddleWare vs CustomRequest for check user rights

Let's say there some users who have several posts. Every user has many posts, and every post belongs to one user. To change post frontend uses URL like users/1/posts/3. The goal is to check, that post number 3 belongs to user number 1. There are several ways to do it:

1. Check inside controller method or service(bad method IMHO)
2. Check inside custom request (authorize function)
3. Check inside middleware

I choose between the last 2, but have some doubts. The custom request should contain validation rules and do not be linked with authorization(SOLID), and I don't know if it's good to do it inside middleware.

via Chebli Mohamed