add /auth for docker compatibility

This endpoint just validates credentials:
https://github.com/moby/moby/blob/v20.10.4/api/swagger.yaml#L7936-L7977

Fixes: #9564
Signed-off-by: troyready <troy@troyready.com>

2 files changed, 31 insertions, 2 deletions

diff --git a/pkg/api/server/register_auth.go b/pkg/api/server/register_auth.go
index 1e5474462..56e115e30 100644
--- a/pkg/api/server/register_auth.go
+++ b/pkg/api/server/register_auth.go
@@ -1,13 +1,33 @@
 package server
 
 import (
+	"net/http"
+
 	"github.com/containers/podman/v3/pkg/api/handlers/compat"
 	"github.com/gorilla/mux"
 )
 
 func (s *APIServer) registerAuthHandlers(r *mux.Router) error {
-	r.Handle(VersionedPath("/auth"), s.APIHandler(compat.UnsupportedHandler))
+	// swagger:operation POST /auth compat auth
+	// ---
+	//   summary: Check auth configuration
+	//   tags:
+	//    - system (compat)
+	//   produces:
+	//   - application/json
+	//   parameters:
+	//    - in: body
+	//      name: authConfig
+	//      description: Authentication to check
+	//      schema:
+	//        $ref: "#/definitions/AuthConfig"
+	//   responses:
+	//     200:
+	//       $ref: "#/responses/SystemAuthResponse"
+	//     500:
+	//       $ref: "#/responses/InternalError"
+	r.Handle(VersionedPath("/auth"), s.APIHandler(compat.Auth)).Methods(http.MethodPost)
 	// Added non version path to URI to support docker non versioned paths
-	r.Handle("/auth", s.APIHandler(compat.UnsupportedHandler))
+	r.Handle("/auth", s.APIHandler(compat.Auth)).Methods(http.MethodPost)
 	return nil
 }
diff --git a/pkg/api/server/swagger.go b/pkg/api/server/swagger.go
index 92efb8ef3..12fd083bb 100644
--- a/pkg/api/server/swagger.go
+++ b/pkg/api/server/swagger.go
@@ -226,3 +226,12 @@ type swagSystemPruneReport struct {
 		entities.SystemPruneReport
 	}
 }
+
+// Auth response
+// swagger:response SystemAuthResponse
+type swagSystemAuthResponse struct {
+	// in:body
+	Body struct {
+		entities.AuthReport
+	}
+}