dev/asn1-wrap-ed25519.go

   1 /*
   2  * MacGDBp
   3  * Copyright (c) 2020, Blue Static <https://www.bluestatic.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it under the terms of the GNU
   6  * General Public License as published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
  10  * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with this program; if not,
  14  * write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  15  */
  16
  17 /*
  18 asn1-wrap-ed25519 takes a raw private key from signer-ed25519 and reencodes it as PEM PKCS8 (ASN.1).
  19
  20 The raw keys generated by signer-ed25519 are not compatible with the OpenSSL
  21 command. By storing it in PKCS8, the keys can be used with openssl commands.
  22
  23 Usage:
  24
  25         ./signer-ed25519 -new-key > out.key
  26         ./asn1-wrap-ed25519 out.key > out-wrapped.key
  27 */
  28 package main
  29
  30 import (
  31         "crypto/ed25519"
  32         "crypto/x509"
  33         "encoding/pem"
  34         "fmt"
  35         "io/ioutil"
  36         "os"
  37 )
  38
  39 func main() {
  40         keyfile := os.Args[1]
  41
  42         keyPemData, err := ioutil.ReadFile(keyfile)
  43         if err != nil {
  44                 fmt.Fprintf(os.Stderr, "Failed to read key: %v\n", err)
  45                 os.Exit(1)
  46         }
  47
  48         keyPem, _ := pem.Decode(keyPemData)
  49         if keyPem == nil {
  50                 fmt.Fprintf(os.Stderr, "Failed to decode PEM: %v\n", err)
  51                 os.Exit(1)
  52         }
  53
  54         key := ed25519.PrivateKey(keyPem.Bytes)
  55
  56         asn1Bytes, err := x509.MarshalPKCS8PrivateKey(key)
  57         if err != nil {
  58                 fmt.Fprintf(os.Stderr, "Failed to ASN.1 encode key: %v\n", err)
  59                 os.Exit(1)
  60         }
  61
  62         asn1Pem := &pem.Block{Type: "ED25519 PRIVATE KEY", Bytes: asn1Bytes}
  63
  64         err = pem.Encode(os.Stdout, asn1Pem)
  65         if err != nil {
  66                 fmt.Println("Failed to PEM-encode ASN.1 key: %v\n", err)
  67                 os.Exit(1)
  68         }
  69 }