initial commit

main.go

@@ -0,0 +1,112 @@
+package main
+
+import (
+	// "bytes"
+	"crypto/sha512"
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/ProtonMail/go-crypto/openpgp"
+	"github.com/ProtonMail/go-crypto/openpgp/armor"
+	"github.com/ProtonMail/go-crypto/openpgp/eddsa"
+	"github.com/ProtonMail/go-crypto/openpgp/packet"
+	 "github.com/davecgh/go-spew/spew"
+	"golang.org/x/crypto/ssh"
+
+	"strings"
+
+	"crypto/ed25519"
+	"errors"
+	"reflect"
+
+	// "filippo.io/edwards25519"
+	"github.com/Mic92/ssh-to-age/bech32"
+	"golang.org/x/crypto/curve25519"
+	// "golang.org/x/crypto/curve25519"
+)
+
+func readEntity(keypath string) (*openpgp.Entity, error) {
+	f, err := os.Open(keypath)
+	if err != nil {
+		log.Println("Error opening file")
+		return nil, err
+	}
+	defer f.Close()
+	block, err := armor.Decode(f)
+	if err != nil {
+		log.Println("decoding")
+		return nil, err
+	}
+	return openpgp.ReadEntity(packet.NewReader(block.Body))
+}
+
+var (
+	UnsupportedKeyType = errors.New("only ed25519 keys are supported")
+)
+
+func ed25519PrivateKeyToCurve25519(pk ed25519.PrivateKey) ([]byte, error) {
+	h := sha512.New()
+	_, err := h.Write(pk.Seed())
+	if err != nil {
+		return []byte{}, err
+	}
+	out := h.Sum(nil)
+	return out[:curve25519.ScalarSize], nil
+}
+
+func SSHPrivateKeyToAge(sshKey, passphrase []byte) (*string, error) {
+	var (
+		privateKey interface{}
+		err        error
+	)
+	if len(passphrase) > 0 {
+		privateKey, err = ssh.ParseRawPrivateKeyWithPassphrase(sshKey, passphrase)
+	} else {
+		privateKey, err = ssh.ParseRawPrivateKey(sshKey)
+	}
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse ssh private key: %w", err)
+	}
+
+	ed25519Key, ok := privateKey.(*ed25519.PrivateKey)
+	if !ok {
+		return nil, fmt.Errorf("got %s key type but: %w", reflect.TypeOf(privateKey), UnsupportedKeyType)
+	}
+
+	bytes, err := ed25519PrivateKeyToCurve25519(*ed25519Key) //THIS
+	if err != nil {
+		return nil, err
+	}
+
+	s, err := bech32.Encode("AGE-SECRET-KEY-", bytes)
+	if err != nil {
+		return nil, err
+	}
+	s = strings.ToUpper(s)
+	return &s, nil
+}
+
+func main() {
+
+	e, err := readEntity("test-key.asc")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	log.Println(reflect.TypeOf(e.PrivateKey.PrivateKey))
+
+	castkey, ok := e.PrivateKey.PrivateKey.(*eddsa.PrivateKey)
+	if !ok {
+		log.Fatal("failed to cast")
+	}
+	spew.Dump(castkey)
+
+	agekey, err := SSHPrivateKeyToAge(castkey.D, []byte{})
+
+	if err != nil {
+		log.Fatal(err)
+	}
+	log.Println(agekey)
+
+}