Fix transferring data using tar

Instead of relying on the remote server to create tar files
with the right account IDs (which the remote server doesn't
even know, when the client and server run under different accounts),
have the remote client ignore the account IDs when unpacking.

Then just hard-code 0 in the remote server, so that the remote
server's account identity does not leak in the tar file contents.

Compare containers/image#1627 .

[NO NEW TESTS NEEDED] : #18563
suggests that existing tests already cover these code paths / properties.

Signed-off-by: Miloslav Trmač <mitr@redhat.com>

pkg/api/handlers/libpod/images.go

@@ -27,7 +27,6 @@ import (
 	"github.com/containers/podman/v4/pkg/domain/infra/abi"
 	domainUtils "github.com/containers/podman/v4/pkg/domain/utils"
 	"github.com/containers/podman/v4/pkg/errorhandling"
-	"github.com/containers/podman/v4/pkg/rootless"
 	"github.com/containers/podman/v4/pkg/util"
 	utils2 "github.com/containers/podman/v4/utils"
 	"github.com/containers/storage"
@@ -330,10 +329,7 @@ func ExportImages(w http.ResponseWriter, r *http.Request) {
 	}
 
 	tarOptions := &archive.TarOptions{
-		ChownOpts: &idtools.IDPair{
-			UID: rootless.GetRootlessUID(),
-			GID: rootless.GetRootlessGID(),
-		},
+		ChownOpts: &idtools.IDPair{UID: 0, GID: 0},
 	}
 	tar, err := chrootarchive.Tar(output, tarOptions, output)
 	if err != nil {

pkg/domain/infra/tunnel/images.go

@@ -336,7 +336,7 @@ func (ir *ImageEngine) Save(ctx context.Context, nameOrID string, tags []string,
 		return err
 	}
 
-	return archive.Untar(f, opts.Output, nil)
+	return archive.Untar(f, opts.Output, &archive.TarOptions{NoLchown: true})
 }
 
 func (ir *ImageEngine) Search(ctx context.Context, term string, opts entities.ImageSearchOptions) ([]entities.ImageSearchReport, error) {