cli: add keygen command (#118)

* cli: factor out key generation

* cli: add keygen command

cli/init.go

@@ -8,8 +8,6 @@ import (
 
 	"github.com/DataDrake/cli-ng/v2/cmd"
 	"github.com/hyprspace/hyprspace/schema"
-	"github.com/libp2p/go-libp2p/core/crypto"
-	"github.com/libp2p/go-libp2p/core/peer"
 	"github.com/multiformats/go-multibase"
 )
 
@@ -39,10 +37,7 @@ func InitRun(r *cmd.Root, c *cmd.Sub) {
 		configPath = "/etc/hyprspace/" + ifName + ".json"
 	}
 
-	privKey, _, err := crypto.GenerateKeyPair(crypto.Ed25519, 256)
-	checkErr(err)
-
-	keyBytes, err := crypto.MarshalPrivateKey(privKey)
+	keyBytes, peerId, err := GenerateKeyPair()
 	checkErr(err)
 
 	// Setup an initial default config.
@@ -72,8 +67,7 @@ func InitRun(r *cmd.Root, c *cmd.Sub) {
 	checkErr(err)
 
 	fmt.Printf("Initialized new config at %s\n", configPath)
-	peerId, err := peer.IDFromPrivateKey(privKey)
-	if err == nil {
+
 	fmt.Println("Add this entry to your other peers:")
 	fmt.Println("{")
 	name := c.Flags.(*InitFlags).Name
@@ -88,5 +82,4 @@ func InitRun(r *cmd.Root, c *cmd.Sub) {
 	}
 	fmt.Printf("  \"id\": \"%s\"\n", peerId)
 	fmt.Println("}")
-	}
 }

cli/keygen.go

@@ -0,0 +1,50 @@
+package cli
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/DataDrake/cli-ng/v2/cmd"
+	"github.com/multiformats/go-multibase"
+)
+
+type KeygenFlags struct {
+	PrivateKeyFile string `long:"private-key-file" desc:"Path to private key file."`
+	PublicKeyFile  string `long:"public-key-file" desc:"Path to public key file. If not specified, prints to stdout."`
+}
+
+// Keygen creates a new keypair and writes each key to a file.
+var Keygen = cmd.Sub{
+	Name:  "keygen",
+	Short: "Generate a new keypair",
+	Flags: &KeygenFlags{},
+	Run:   KeygenRun,
+}
+
+func KeygenRun(r *cmd.Root, c *cmd.Sub) {
+	flags := c.Flags.(*KeygenFlags)
+
+	if flags.PrivateKeyFile == "" {
+		log.Fatal("--private-key-file is required")
+	}
+
+	keyBytes, peerId, err := GenerateKeyPair()
+	checkErr(err)
+
+	encoded := multibase.MustNewEncoder(multibase.Base58BTC).Encode(keyBytes)
+
+	err = os.WriteFile(flags.PrivateKeyFile, []byte(encoded), 0600)
+	checkErr(err)
+
+	fmt.Fprintf(os.Stderr, "Private key written to %s\n", flags.PrivateKeyFile)
+
+	if flags.PublicKeyFile != "" {
+		err = os.WriteFile(flags.PublicKeyFile, []byte(peerId.String()), 0644)
+		checkErr(err)
+
+		fmt.Fprintf(os.Stderr, "Public key written to %s\n", flags.PublicKeyFile)
+	} else {
+		fmt.Println(peerId.String())
+	}
+}

cli/root.go

@@ -30,6 +30,7 @@ func init() {
 
 	cmd.Register(&cmd.Help)
 	cmd.Register(&Init)
+	cmd.Register(&Keygen)
 	cmd.Register(&Up)
 	cmd.Register(&Status)
 	cmd.Register(&Peers)

cli/util.go

@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"os"
 
+	"github.com/libp2p/go-libp2p/core/crypto"
+	"github.com/libp2p/go-libp2p/core/peer"
 	"github.com/mattn/go-isatty"
 )
 
@@ -16,3 +18,24 @@ func printListF(strings []string, handler func(string) string) {
 func isTTY() bool {
 	return isatty.IsTerminal(os.Stdout.Fd())
 }
+
+func GenerateKeyPair() ([]byte, peer.ID, error) {
+	var zeroID peer.ID
+
+	privKey, _, err := crypto.GenerateKeyPair(crypto.Ed25519, 256)
+	if err != nil {
+		return nil, zeroID, err
+	}
+
+	keyBytes, err := crypto.MarshalPrivateKey(privKey)
+	if err != nil {
+		return nil, zeroID, err
+	}
+
+	peerId, err := peer.IDFromPrivateKey(privKey)
+	if err != nil {
+		return nil, zeroID, err
+	}
+
+	return keyBytes, peerId, nil
+}