pgp-key-management/keys/generate-keys.go

package main

import (
	"crypto/rand"
	"crypto/rsa"
	"crypto/x509"
	"encoding/pem"
	"fmt"
	"os"
	"path/filepath"
	//"io"

	//"github.com/ProtonMail/go-crypto/openpgp/armor"
)

func main() {
	err := run()
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}
}

func run() error {
	names := []string{
		"internal-A",
		"internal-B",

		"customer-A",
		"customer-B",
		"customer-C",
	}

	for _, name := range names {
		fmt.Println("Generating keypair for", name)
		err := keypair(name)
		if err != nil {
			return err
		}
	}

	return nil
}

const (
	keyDir string = "./"
)

func keypair(name string) error {
	const bitSize int = 4096

	key, err := rsa.GenerateKey(rand.Reader, bitSize)
	if err != nil {
		return err
	}

	pub := key.Public()

	keyPem := pem.EncodeToMemory(
		&pem.Block{
			Type: "RSA PRIVATE KEY",
			Bytes: x509.MarshalPKCS1PrivateKey(key),
		},
	)

	pubPem := pem.EncodeToMemory(
		&pem.Block{
			Type: "RSA PUBLIC KEY",
			Bytes: x509.MarshalPKCS1PublicKey(pub.(*rsa.PublicKey)),
		},
	)

	err = os.WriteFile(filepath.Join(keyDir, "public", name+".pem"), pubPem, 0644)
	if err != nil {
		return err
	}

	err = os.WriteFile(filepath.Join(keyDir, "private", name+".pem"), keyPem, 0644)
	if err != nil {
		return err
	}

	pubDerRaw, err := x509.MarshalPKIXPublicKey(pub.(*rsa.PublicKey))
	if err != nil {
		return err
	}

	pubDer := pem.EncodeToMemory(
		&pem.Block{
			Type: "RSA PUBLIC KEY",
			Bytes: pubDerRaw,
		},
	)

	err = os.WriteFile(filepath.Join(keyDir, "public", name+".asc"), pubDer, 0644)
	if err != nil {
		return err
	}

	//err = encodeToArmor(filepath.Join(keyDir, "public", name+".asc"), pub.(*rsa.PublicKey))
	//if err != nil {
	//	return err
	//}

	return nil
}

//func encodeToArmor(filename string, key *rsa.PublicKey) error {
//	outfile, err := os.Create(filename)
//	if err != nil {
//		return err
//	}
//	defer outfile.Close()
//
//	writer, err := armor.Encode(outfile, "PGP PUBLIC KEY", nil)
//	if err != nil {
//		return err
//	}
//	defer writer.Close()
//
//	_, err = writer.Write(key.)
//	return err
//}