Add "keys copy-targets" command

This helps operators not need the super secure offline root keys
for rolling out updates

Signed-off-by: Andy Doan <andy@foundries.io>

subcommands/keys/copy_targets.go

@@ -0,0 +1,68 @@
+package keys
+
+import (
+	"encoding/json"
+	"errors"
+	"strings"
+
+	"github.com/foundriesio/fioctl/client"
+	"github.com/foundriesio/fioctl/subcommands"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+func init() {
+	copy := &cobra.Command{
+		Use:   "copy-targets <offline key archive> <new targets archive>",
+		Short: "Copy the target signing credentials from the offline key archive",
+		Run:   doCopyTargets,
+		Args:  cobra.ExactArgs(2),
+		Long: `This command extracts the target signing credentials required for initializing 
+waves into a new tarball so that the offline key archive isn't required for
+rolling out production updates. This should be run after each target key
+rotation and distributed to the operator in charge of production OTAs.`,
+	}
+	subcommands.RequireFactory(copy)
+	cmd.AddCommand(copy)
+}
+
+func doCopyTargets(cmd *cobra.Command, args []string) {
+	factory := viper.GetString("factory")
+	credsFile := args[0]
+	creds, err := GetOfflineCreds(credsFile)
+	subcommands.DieNotNil(err)
+
+	root, err := api.TufRootGet(factory)
+	subcommands.DieNotNil(err)
+
+	targetsCreds, err := createTargetsCreds(factory, *root, creds)
+	subcommands.DieNotNil(err)
+	saveCreds(args[1], targetsCreds)
+}
+
+func createTargetsCreds(factory string, root client.AtsTufRoot, creds OfflineCreds) (OfflineCreds, error) {
+	targets := make(OfflineCreds)
+	onlinePub, err := api.GetFoundriesTargetsKey(factory)
+	subcommands.DieNotNil(err)
+	for _, keyid := range root.Signed.Roles["targets"].KeyIDs {
+		pubkey := root.Signed.Keys[keyid].KeyValue.Public
+		if pubkey != onlinePub.KeyValue.Public {
+			pubkey = strings.TrimSpace(pubkey)
+			for k, v := range creds {
+				if strings.HasSuffix(k, ".pub") {
+					tk := client.AtsKey{}
+					if err := json.Unmarshal(v, &tk); err != nil {
+						return nil, err
+					}
+					if strings.TrimSpace(tk.KeyValue.Public) == pubkey {
+						targets[k] = v
+						pkname := strings.Replace(k, ".pub", ".sec", 1)
+						targets[pkname] = creds[pkname]
+						return targets, nil
+					}
+				}
+			}
+		}
+	}
+	return targets, errors.New("Unable to find offline target key for factory")
+}

subcommands/keys/rotate_root.go

@@ -226,7 +226,11 @@ Please move this file somewhere safe before re-running this command.`,
 			path,
 		))
 	}
+	saveCreds(path, creds)
+	return path
+}
 
+func saveCreds(path string, creds OfflineCreds) {
 	file, err := os.Create(path)
 	subcommands.DieNotNil(err)
 	defer file.Close()
@@ -246,7 +250,6 @@ Please move this file somewhere safe before re-running this command.`,
 		_, err := tarWriter.Write(val)
 		subcommands.DieNotNil(err)
 	}
-	return path
 }
 
 func findRoot(root client.AtsTufRoot, creds OfflineCreds) (string, *rsa.PrivateKey, error) {