fix: server info leakage through errors (#93)

pkg/api/graphql/resolvers/mutations.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/graph-gophers/graphql-go"
 	"github.com/sassoftware/event-provenance-registry/pkg/epr"
+	eprErrors "github.com/sassoftware/event-provenance-registry/pkg/errors"
 	"github.com/sassoftware/event-provenance-registry/pkg/message"
 	"github.com/sassoftware/event-provenance-registry/pkg/storage"
 )
@@ -22,23 +23,23 @@ type MutationResolver struct {
 func (r *MutationResolver) CreateEvent(args struct{ Event epr.EventInput }) (graphql.ID, error) {
 	event, err := epr.CreateEvent(r.msgProducer, r.Connection, args.Event)
 	if err != nil {
-		return "", err
+		return "", eprErrors.SanitizeError(err)
 	}
 	return event.ID, nil
 }
 
 func (r *MutationResolver) CreateEventReceiver(args struct{ EventReceiver epr.EventReceiverInput }) (graphql.ID, error) {
 	eventReceiver, err := epr.CreateEventReceiver(r.msgProducer, r.Connection, args.EventReceiver)
 	if err != nil {
-		return "", err
+		return "", eprErrors.SanitizeError(err)
 	}
 	return eventReceiver.ID, nil
 }
 
 func (r *MutationResolver) CreateEventReceiverGroup(args struct{ EventReceiverGroup epr.EventReceiverGroupInput }) (graphql.ID, error) {
 	eventReceiverGroup, err := epr.CreateEventReceiverGroup(r.msgProducer, r.Connection, args.EventReceiverGroup)
 	if err != nil {
-		return "", err
+		return "", eprErrors.SanitizeError(err)
 	}
 	return eventReceiverGroup.ID, nil
 }
@@ -47,7 +48,7 @@ func (r *MutationResolver) SetEventReceiverGroupEnabled(args struct{ ID graphql.
 	err := storage.SetEventReceiverGroupEnabled(r.Connection.Client, args.ID, true)
 	if err != nil {
 		slog.Error("error setting event receiver group enabled", "error", err, "id", args.ID)
-		return "", err
+		return "", eprErrors.SanitizeError(err)
 	}
 	slog.Info("updated", "eventReceiverGroupEnabled", args.ID)
 	return args.ID, nil
@@ -57,7 +58,7 @@ func (r *MutationResolver) SetEventReceiverGroupDisabled(args struct{ ID graphql
 	err := storage.SetEventReceiverGroupEnabled(r.Connection.Client, args.ID, false)
 	if err != nil {
 		slog.Error("error setting event receiver group disabled", "error", err, "id", args.ID)
-		return "", err
+		return "", eprErrors.SanitizeError(err)
 	}
 	slog.Info("updated", "eventReceiverGroupDisabled", args.ID)
 	return args.ID, nil

pkg/api/graphql/resolvers/query.go

@@ -2,6 +2,7 @@ package resolvers
 
 import (
 	"github.com/graph-gophers/graphql-go"
+	eprErrors "github.com/sassoftware/event-provenance-registry/pkg/errors"
 	"github.com/sassoftware/event-provenance-registry/pkg/storage"
 )
 
@@ -10,25 +11,31 @@ type QueryResolver struct {
 }
 
 func (r *QueryResolver) Events(args struct{ Event FindEventInput }) ([]storage.Event, error) {
-	return storage.FindEvent(r.Connection.Client, args.Event.toMap())
+	events, err := storage.FindEvent(r.Connection.Client, args.Event.toMap())
+	return events, eprErrors.SanitizeError(err)
 }
 
 func (r *QueryResolver) EventReceivers(args struct{ EventReceiver FindEventReceiverInput }) ([]storage.EventReceiver, error) {
-	return storage.FindEventReceiver(r.Connection.Client, args.EventReceiver.toMap())
+	receivers, err := storage.FindEventReceiver(r.Connection.Client, args.EventReceiver.toMap())
+	return receivers, eprErrors.SanitizeError(err)
 }
 
 func (r *QueryResolver) EventReceiverGroups(args struct{ EventReceiverGroup FindEventReceiverGroupInput }) ([]storage.EventReceiverGroup, error) {
-	return storage.FindEventReceiverGroup(r.Connection.Client, args.EventReceiverGroup.toMap())
+	groups, err := storage.FindEventReceiverGroup(r.Connection.Client, args.EventReceiverGroup.toMap())
+	return groups, eprErrors.SanitizeError(err)
 }
 
 func (r *QueryResolver) EventsByID(args struct{ ID graphql.ID }) ([]storage.Event, error) {
-	return storage.FindEventByID(r.Connection.Client, args.ID)
+	events, err := storage.FindEventByID(r.Connection.Client, args.ID)
+	return events, eprErrors.SanitizeError(err)
 }
 
 func (r *QueryResolver) EventReceiversByID(args struct{ ID graphql.ID }) ([]storage.EventReceiver, error) {
-	return storage.FindEventReceiverByID(r.Connection.Client, args.ID)
+	receivers, err := storage.FindEventReceiverByID(r.Connection.Client, args.ID)
+	return receivers, eprErrors.SanitizeError(err)
 }
 
 func (r *QueryResolver) EventReceiverGroupsByID(args struct{ ID graphql.ID }) ([]storage.EventReceiverGroup, error) {
-	return storage.FindEventReceiverGroupByID(r.Connection.Client, args.ID)
+	groups, err := storage.FindEventReceiverGroupByID(r.Connection.Client, args.ID)
+	return groups, eprErrors.SanitizeError(err)
 }

pkg/api/rest/rest.go

@@ -49,15 +49,19 @@ func handleResponse(w http.ResponseWriter, r *http.Request, data any, err error)
 		return
 	}
 
-	resp.Errors = []string{err.Error()}
+	var status int
 	switch err.(type) {
 	case eprErrors.MissingObjectError:
-		render.Status(r, http.StatusNotFound)
+		status = http.StatusNotFound
 	case eprErrors.InvalidInputError:
-		render.Status(r, http.StatusBadRequest)
+		status = http.StatusBadRequest
 	default:
-		render.Status(r, http.StatusInternalServerError)
+		status = http.StatusInternalServerError
 	}
+	render.Status(r, status)
+
+	resp.Errors = []string{eprErrors.SanitizeError(err).Error()}
+
 	slog.Error("error during request", "error", err, "url", r.URL)
 	render.JSON(w, r, resp)
 }

pkg/errors/errors.go

@@ -1,6 +1,9 @@
 package errors
 
-import "fmt"
+import (
+	"errors"
+	"fmt"
+)
 
 type MissingObjectError struct {
 	Msg string
@@ -17,3 +20,23 @@ type InvalidInputError struct {
 func (e InvalidInputError) Error() string {
 	return fmt.Sprintf("invalid input: %s", e.Msg)
 }
+
+func SanitizeError(err error) error {
+	if err == nil {
+		return nil
+	}
+
+	isServerErr := false
+	switch err.(type) {
+	case MissingObjectError:
+	case InvalidInputError:
+	default:
+		isServerErr = true
+	}
+
+	if isServerErr {
+		// don't expose server internals
+		err = errors.New("internal server error")
+	}
+	return err
+}