Implment sbctl debug command

It's to help us debug issues with sbctl and UEFI things.

Fixes: #287

Signed-off-by: Morten Linderud <[email protected]>

cmd/sbctl/debug.go

@@ -0,0 +1,125 @@
+package main
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"encoding/json"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+
+	"github.com/foxboron/sbctl/config"
+	"github.com/foxboron/sbctl/logging"
+	"github.com/goccy/go-yaml"
+	"github.com/spf13/cobra"
+)
+
+type DebugCmdOptions struct {
+	Output string
+}
+
+var (
+	debugCmdOptions = DebugCmdOptions{}
+	debugCmd        = &cobra.Command{
+		Use:    "debug",
+		Short:  "Produce debug information for sbctl",
+		Hidden: true,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			state := cmd.Context().Value(stateDataKey{}).(*config.State)
+			return ProduceDebugInformation(state)
+		},
+	}
+)
+
+func ProduceDebugInformation(state *config.State) error {
+	output, err := filepath.Abs(debugCmdOptions.Output)
+	if err != nil {
+		return err
+	}
+	logging.Print("Creating a debug dump to %s...\n", output)
+	file, err := os.Create(output)
+	if err != nil {
+		return fmt.Errorf("could not produce debug tarball: %v", err)
+	}
+
+	defer file.Close()
+	gzipWriter := gzip.NewWriter(file)
+	defer gzipWriter.Close()
+
+	tw := tar.NewWriter(gzipWriter)
+	defer tw.Close()
+
+	writeTw := func(n string, b []byte) error {
+		hdr := &tar.Header{
+			Name: filepath.Base(n),
+			Mode: 0600,
+			Size: int64(len(b)),
+		}
+		if err := tw.WriteHeader(hdr); err != nil {
+			return err
+		}
+		if _, err := tw.Write(b); err != nil {
+			return err
+		}
+		return nil
+	}
+
+	efifiles, err := filepath.Glob("/sys/firmware/efi/efivars/*-8be4df61-93ca-11d2-aa0d-00e098032b8c")
+	if err != nil {
+		return err
+	}
+	efifiles = append(efifiles,
+		"/sys/firmware/efi/efivars/dbx-d719b2cb-3d3a-4596-a3bc-dad00e67656f",
+		"/sys/firmware/efi/efivars/db-d719b2cb-3d3a-4596-a3bc-dad00e67656f",
+	)
+
+	for _, f := range efifiles {
+		b, err := os.ReadFile(f)
+		if err != nil {
+			log.Print(err)
+			continue
+		}
+
+		if err := writeTw(f, b); err != nil {
+			return err
+		}
+	}
+
+	stateb, err := json.Marshal(state)
+	if err != nil {
+		return err
+	}
+	if err := writeTw("state.json", stateb); err != nil {
+		return err
+	}
+
+	configby, err := yaml.Marshal(state.Config)
+	if err != nil {
+		return err
+	}
+	if err := writeTw("config.yaml", configby); err != nil {
+		return err
+	}
+
+	configbj, err := json.Marshal(state.Config)
+	if err != nil {
+		return err
+	}
+	if err := writeTw("config.json", configbj); err != nil {
+		return err
+	}
+	return nil
+}
+
+func debugCmdFlags(cmd *cobra.Command) {
+	f := cmd.Flags()
+	f.StringVarP(&debugCmdOptions.Output, "output", "o", "sbctl_debug.tar.gz", "debug output")
+}
+
+func init() {
+	debugCmdFlags(debugCmd)
+	CliCommands = append(CliCommands, cliCommand{
+		Cmd: debugCmd,
+	})
+}

config/config.go

@@ -49,6 +49,8 @@ func (k *Keys) GetKeysConfigs() []*KeyConfig {
 	}
 }
 
+// Note: Anything serialized as part of this struct will end up in a public
+// debug dump at some point, probably.
 type Config struct {
 	Landlock   bool          `json:"landlock"`
 	Keydir     string        `json:"keydir"`