Merge pull request #12351 from adrianreber/2021-11-18-restore-runtime-verification

Restore runtime verification

1 files changed, 43 insertions, 0 deletions

diff --git a/cmd/podman/root.go b/cmd/podman/root.go
index 9e4c8d24d..bccc559ce 100644
--- a/cmd/podman/root.go
+++ b/cmd/podman/root.go
@@ -15,6 +15,7 @@ import (
 	"github.com/containers/podman/v3/cmd/podman/registry"
 	"github.com/containers/podman/v3/cmd/podman/validate"
 	"github.com/containers/podman/v3/libpod/define"
+	"github.com/containers/podman/v3/pkg/checkpoint/crutils"
 	"github.com/containers/podman/v3/pkg/domain/entities"
 	"github.com/containers/podman/v3/pkg/parallel"
 	"github.com/containers/podman/v3/pkg/rootless"
@@ -114,6 +115,48 @@ func persistentPreRunE(cmd *cobra.Command, args []string) error {
 
 	cfg := registry.PodmanConfig()
 
+	// Currently it is only possible to restore a container with the same runtime
+	// as used for checkpointing. It should be possible to make crun and runc
+	// compatible to restore a container with another runtime then checkpointed.
+	// Currently that does not work.
+	// To make it easier for users we will look into the checkpoint archive and
+	// set the runtime to the one used during checkpointing.
+	if !registry.IsRemote() && cmd.Name() == "restore" {
+		if cmd.Flag("import").Changed {
+			runtime, err := crutils.CRGetRuntimeFromArchive(cmd.Flag("import").Value.String())
+			if err != nil {
+				return errors.Wrapf(
+					err,
+					"failed extracting runtime information from %s",
+					cmd.Flag("import").Value.String(),
+				)
+			}
+			if cfg.RuntimePath == "" {
+				// If the user did not select a runtime, this takes the one from
+				// the checkpoint archives and tells Podman to use it for the restore.
+				runtimeFlag := cmd.Root().Flags().Lookup("runtime")
+				if runtimeFlag == nil {
+					return errors.Errorf(
+						"Unexcpected error setting runtime to '%s' for restore",
+						*runtime,
+					)
+				}
+				runtimeFlag.Value.Set(*runtime)
+				runtimeFlag.Changed = true
+				logrus.Debugf("Checkpoint was created using '%s'. Restore will use the same runtime", *runtime)
+			} else if cfg.RuntimePath != *runtime {
+				// If the user selected a runtime on the command-line this checks if
+				// it is the same then during checkpointing and errors out if not.
+				return errors.Errorf(
+					"checkpoint archive %s was created with runtime '%s' and cannot be restored with runtime '%s'",
+					cmd.Flag("import").Value.String(),
+					*runtime,
+					cfg.RuntimePath,
+				)
+			}
+		}
+	}
+
 	// --connection is not as "special" as --remote so we can wait and process it here
 	conn := cmd.Root().LocalFlags().Lookup("connection")
 	if conn != nil && conn.Changed {