constellation/cli/cmd/recover.go
2022-06-08 11:53:55 +02:00

154 lines
4.5 KiB
Go

package cmd
import (
"context"
"encoding/base64"
"errors"
"regexp"
"strings"
"github.com/edgelesssys/constellation/cli/cloud/cloudcmd"
"github.com/edgelesssys/constellation/cli/internal/proto"
"github.com/edgelesssys/constellation/coordinator/util"
"github.com/edgelesssys/constellation/internal/cloud/cloudprovider"
"github.com/edgelesssys/constellation/internal/constants"
"github.com/edgelesssys/constellation/internal/file"
"github.com/edgelesssys/constellation/internal/state"
"github.com/spf13/afero"
"github.com/spf13/cobra"
)
var diskUUIDRegexp = regexp.MustCompile("^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$")
func newRecoverCmd() *cobra.Command {
cmd := &cobra.Command{
Use: "recover",
Short: "Recover a completely stopped Constellation cluster",
Long: "Recover a Constellation cluster by sending a recovery key to an instance in the boot stage." +
"\nThis is only required if instances restart without other instances available for bootstrapping.",
Args: cobra.ExactArgs(0),
RunE: runRecover,
}
cmd.Flags().StringP("endpoint", "e", "", "endpoint of the instance, passed as HOST[:PORT] (required)")
must(cmd.MarkFlagRequired("endpoint"))
cmd.Flags().String("disk-uuid", "", "disk UUID of the encrypted state disk (required)")
must(cmd.MarkFlagRequired("disk-uuid"))
cmd.Flags().String("master-secret", constants.MasterSecretFilename, "path to base64-encoded master secret")
return cmd
}
func runRecover(cmd *cobra.Command, args []string) error {
fileHandler := file.NewHandler(afero.NewOsFs())
recoveryClient := &proto.KeyClient{}
defer recoveryClient.Close()
return recover(cmd.Context(), cmd, fileHandler, recoveryClient)
}
func recover(ctx context.Context, cmd *cobra.Command, fileHandler file.Handler, recoveryClient recoveryClient) error {
flags, err := parseRecoverFlags(cmd, fileHandler)
if err != nil {
return err
}
var stat state.ConstellationState
if err := fileHandler.ReadJSON(constants.StateFilename, &stat); err != nil {
return err
}
provider := cloudprovider.FromString(stat.CloudProvider)
config, err := readConfig(cmd.OutOrStdout(), fileHandler, flags.configPath, provider)
if err != nil {
return err
}
validators, err := cloudcmd.NewValidators(provider, config)
if err != nil {
return err
}
cmd.Print(validators.WarningsIncludeInit())
if err := recoveryClient.Connect(flags.endpoint, validators.V()); err != nil {
return err
}
diskKey, err := deriveStateDiskKey(flags.masterSecret, flags.diskUUID)
if err != nil {
return err
}
if err := recoveryClient.PushStateDiskKey(ctx, diskKey); err != nil {
return err
}
cmd.Println("Pushed recovery key.")
return nil
}
func parseRecoverFlags(cmd *cobra.Command, fileHandler file.Handler) (recoverFlags, error) {
endpoint, err := cmd.Flags().GetString("endpoint")
if err != nil {
return recoverFlags{}, err
}
endpoint, err = validateEndpoint(endpoint, constants.CoordinatorPort)
if err != nil {
return recoverFlags{}, err
}
diskUUID, err := cmd.Flags().GetString("disk-uuid")
if err != nil {
return recoverFlags{}, err
}
if match := diskUUIDRegexp.MatchString(diskUUID); !match {
return recoverFlags{}, errors.New("flag '--disk-uuid' isn't a valid LUKS UUID")
}
diskUUID = strings.ToLower(diskUUID)
masterSecretPath, err := cmd.Flags().GetString("master-secret")
if err != nil {
return recoverFlags{}, err
}
masterSecret, err := readMasterSecret(fileHandler, masterSecretPath)
if err != nil {
return recoverFlags{}, err
}
configPath, err := cmd.Flags().GetString("config")
if err != nil {
return recoverFlags{}, err
}
return recoverFlags{
endpoint: endpoint,
diskUUID: diskUUID,
masterSecret: masterSecret,
configPath: configPath,
}, nil
}
type recoverFlags struct {
endpoint string
diskUUID string
masterSecret []byte
configPath string
}
// readMasterSecret reads a base64 encoded master secret from file.
func readMasterSecret(fileHandler file.Handler, filename string) ([]byte, error) {
// Try to read the base64 secret from file
encodedSecret, err := fileHandler.Read(filename)
if err != nil {
return nil, err
}
decoded, err := base64.StdEncoding.DecodeString(string(encodedSecret))
if err != nil {
return nil, err
}
return decoded, nil
}
// deriveStateDiskKey derives a state disk key from a master secret and a disk UUID.
func deriveStateDiskKey(masterKey []byte, diskUUID string) ([]byte, error) {
return util.DeriveKey(masterKey, []byte("Constellation"), []byte("key"+diskUUID), constants.StateDiskKeyLength)
}