registry: unexport auth-related context utilities

The specifics of how the authorization for a request is propagated
through the registry app are private implementation details. Hide those
details from outsiders so they can be changed as needed without fear of
breaking third-party code. Move the utilities for attaching a request's
authorization status to its context and retrieving it from the context
into the registry/handlers package as unexported symbols.

Signed-off-by: Cory Snider <csnider@mirantis.com>

registry/auth/auth.go

@@ -32,22 +32,11 @@
 package auth
 
 import (
-	"context"
 	"errors"
 	"fmt"
 	"net/http"
 )
 
-const (
-	// UserKey is used to get the user object from
-	// a user context
-	UserKey = "auth.user"
-
-	// UserNameKey is used to get the user name from
-	// a user context
-	UserNameKey = "auth.user.name"
-)
-
 var (
 	// ErrInvalidCredential is returned when the auth token does not authenticate correctly.
 	ErrInvalidCredential = errors.New("invalid authorization credential")
@@ -115,63 +104,6 @@ type CredentialAuthenticator interface {
 	AuthenticateUser(username, password string) error
 }
 
-// WithUser returns a context with the authorized user info.
-func WithUser(ctx context.Context, user UserInfo) context.Context {
-	return userInfoContext{
-		Context: ctx,
-		user:    user,
-	}
-}
-
-type userInfoContext struct {
-	context.Context
-	user UserInfo
-}
-
-func (uic userInfoContext) Value(key interface{}) interface{} {
-	switch key {
-	case UserKey:
-		return uic.user
-	case UserNameKey:
-		return uic.user.Name
-	}
-
-	return uic.Context.Value(key)
-}
-
-// WithResources returns a context with the authorized resources.
-func WithResources(ctx context.Context, resources []Resource) context.Context {
-	return resourceContext{
-		Context:   ctx,
-		resources: resources,
-	}
-}
-
-type resourceContext struct {
-	context.Context
-	resources []Resource
-}
-
-type resourceKey struct{}
-
-func (rc resourceContext) Value(key interface{}) interface{} {
-	if key == (resourceKey{}) {
-		return rc.resources
-	}
-
-	return rc.Context.Value(key)
-}
-
-// AuthorizedResources returns the list of resources which have
-// been authorized for this request.
-func AuthorizedResources(ctx context.Context) []Resource {
-	if resources, ok := ctx.Value(resourceKey{}).([]Resource); ok {
-		return resources
-	}
-
-	return nil
-}
-
 // InitFunc is the type of an AccessController factory function and is used
 // to register the constructor for different AccesController backends.
 type InitFunc func(options map[string]interface{}) (AccessController, error)

registry/handlers/app.go

@@ -635,7 +635,7 @@ func (app *App) dispatcher(dispatch dispatchFunc) http.Handler {
 		}
 
 		// Add username to request logging
-		context.Context = dcontext.WithLogger(context.Context, dcontext.GetLogger(context.Context, auth.UserNameKey))
+		context.Context = dcontext.WithLogger(context.Context, dcontext.GetLogger(context.Context, userNameKey))
 
 		// sync up context on the request.
 		r = r.WithContext(context)
@@ -822,10 +822,10 @@ func (app *App) authorized(w http.ResponseWriter, r *http.Request, context *Cont
 		return fmt.Errorf("access controller returned neither an access grant nor an error")
 	}
 
-	ctx := auth.WithUser(context.Context, grant.User)
-	ctx = auth.WithResources(ctx, grant.Resources)
+	ctx := withUser(context.Context, grant.User)
+	ctx = withResources(ctx, grant.Resources)
 
-	dcontext.GetLogger(ctx, auth.UserNameKey).Info("authorized request")
+	dcontext.GetLogger(ctx, userNameKey).Info("authorized request")
 	// TODO(stevvooe): This pattern needs to be cleaned up a bit. One context
 	// should be replaced by another, rather than replacing the context on a
 	// mutable object.

registry/handlers/context.go

@@ -77,10 +77,20 @@ func getUploadUUID(ctx context.Context) (uuid string) {
 	return dcontext.GetStringValue(ctx, "vars.uuid")
 }
 
+const (
+	// userKey is used to get the user object from
+	// a user context
+	userKey = "auth.user"
+
+	// userNameKey is used to get the user name from
+	// a user context
+	userNameKey = "auth.user.name"
+)
+
 // getUserName attempts to resolve a username from the context and request. If
 // a username cannot be resolved, the empty string is returned.
 func getUserName(ctx context.Context, r *http.Request) string {
-	username := dcontext.GetStringValue(ctx, auth.UserNameKey)
+	username := dcontext.GetStringValue(ctx, userNameKey)
 
 	// Fallback to request user with basic auth
 	if username == "" {
@@ -93,3 +103,60 @@ func getUserName(ctx context.Context, r *http.Request) string {
 
 	return username
 }
+
+// withUser returns a context with the authorized user info.
+func withUser(ctx context.Context, user auth.UserInfo) context.Context {
+	return userInfoContext{
+		Context: ctx,
+		user:    user,
+	}
+}
+
+type userInfoContext struct {
+	context.Context
+	user auth.UserInfo
+}
+
+func (uic userInfoContext) Value(key interface{}) interface{} {
+	switch key {
+	case userKey:
+		return uic.user
+	case userNameKey:
+		return uic.user.Name
+	}
+
+	return uic.Context.Value(key)
+}
+
+// withResources returns a context with the authorized resources.
+func withResources(ctx context.Context, resources []auth.Resource) context.Context {
+	return resourceContext{
+		Context:   ctx,
+		resources: resources,
+	}
+}
+
+type resourceContext struct {
+	context.Context
+	resources []auth.Resource
+}
+
+type resourceKey struct{}
+
+func (rc resourceContext) Value(key interface{}) interface{} {
+	if key == (resourceKey{}) {
+		return rc.resources
+	}
+
+	return rc.Context.Value(key)
+}
+
+// authorizedResources returns the list of resources which have
+// been authorized for this request.
+func authorizedResources(ctx context.Context) []auth.Resource {
+	if resources, ok := ctx.Value(resourceKey{}).([]auth.Resource); ok {
+		return resources
+	}
+
+	return nil
+}

registry/handlers/manifests.go

@@ -13,7 +13,6 @@ import (
 	"github.com/distribution/distribution/v3/manifest/ocischema"
 	"github.com/distribution/distribution/v3/manifest/schema2"
 	"github.com/distribution/distribution/v3/registry/api/errcode"
-	"github.com/distribution/distribution/v3/registry/auth"
 	"github.com/distribution/distribution/v3/registry/storage/driver"
 	"github.com/distribution/reference"
 	"github.com/gorilla/handlers"
@@ -394,7 +393,7 @@ func (imh *manifestHandler) applyResourcePolicy(manifest distribution.Manifest)
 		return errcode.ErrorCodeDenied.WithMessage(fmt.Sprintf("registry does not allow %s manifest", class))
 	}
 
-	resources := auth.AuthorizedResources(imh)
+	resources := authorizedResources(imh)
 	n := imh.Repository.Named().Name()
 
 	var foundResource bool