distribution/auth/silly/access.go
Josh Hawn 2c3d738a05 Use context for auth access controllers
The auth package has been updated to use "golang.org/x/net/context" for
passing information between the application and the auth backend.

AccessControllers should now set a "auth.user" context value to a AuthUser
struct containing a single "Name" field for now with possible, optional, values
in the future.

The "silly" auth backend always sets the name to "silly", while the "token" auth
backend will set the name to match the "subject" claim of the JWT.

Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
2015-02-04 19:17:33 -08:00

95 lines
2.6 KiB
Go

// Package silly provides a simple authentication scheme that checks for the
// existence of an Authorization header and issues access if is present and
// non-empty.
//
// This package is present as an example implementation of a minimal
// auth.AccessController and for testing. This is not suitable for any kind of
// production security.
package silly
import (
"fmt"
"net/http"
"strings"
"github.com/docker/distribution/auth"
"golang.org/x/net/context"
)
// accessController provides a simple implementation of auth.AccessController
// that simply checks for a non-empty Authorization header. It is useful for
// demonstration and testing.
type accessController struct {
realm string
service string
}
var _ auth.AccessController = &accessController{}
func newAccessController(options map[string]interface{}) (auth.AccessController, error) {
realm, present := options["realm"]
if _, ok := realm.(string); !present || !ok {
return nil, fmt.Errorf(`"realm" must be set for silly access controller`)
}
service, present := options["service"]
if _, ok := service.(string); !present || !ok {
return nil, fmt.Errorf(`"service" must be set for silly access controller`)
}
return &accessController{realm: realm.(string), service: service.(string)}, nil
}
// Authorized simply checks for the existence of the authorization header,
// responding with a bearer challenge if it doesn't exist.
func (ac *accessController) Authorized(ctx context.Context, accessRecords ...auth.Access) (context.Context, error) {
req, err := auth.RequestFromContext(ctx)
if err != nil {
return nil, err
}
if req.Header.Get("Authorization") == "" {
challenge := challenge{
realm: ac.realm,
service: ac.service,
}
if len(accessRecords) > 0 {
var scopes []string
for _, access := range accessRecords {
scopes = append(scopes, fmt.Sprintf("%s:%s:%s", access.Type, access.Resource.Name, access.Action))
}
challenge.scope = strings.Join(scopes, " ")
}
return nil, &challenge
}
return context.WithValue(ctx, "auth.user", auth.UserInfo{Name: "silly"}), nil
}
type challenge struct {
realm string
service string
scope string
}
func (ch *challenge) ServeHTTP(w http.ResponseWriter, r *http.Request) {
header := fmt.Sprintf("Bearer realm=%q,service=%q", ch.realm, ch.service)
if ch.scope != "" {
header = fmt.Sprintf("%s,scope=%q", header, ch.scope)
}
w.Header().Set("Authorization", header)
w.WriteHeader(http.StatusUnauthorized)
}
func (ch *challenge) Error() string {
return fmt.Sprintf("silly authentication challenge: %#v", ch)
}
// init registers the silly auth backend.
func init() {
auth.Register("silly", auth.InitFunc(newAccessController))
}