From 68f357e14f4c8e829b1c85e1fa832ea2e15e1542 Mon Sep 17 00:00:00 2001
From: Robert Sesek <rsesek@bluestatic.org>
Date: Sat, 8 Aug 2020 18:10:55 -0400
Subject: [PATCH] Add a tool to wrap a raw ED25519 key in PKCS8.

This will let the key be used by OpenSSL.
---
 dev/.gitignore           |  1 +
 dev/asn1-wrap-ed25519.go | 70 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)
 create mode 100644 dev/asn1-wrap-ed25519.go

diff --git a/dev/.gitignore b/dev/.gitignore
index a3d806c..8760178 100644
--- a/dev/.gitignore
+++ b/dev/.gitignore
@@ -1,3 +1,4 @@
+asn1-wrap-ed25519
 openssl-sign-ed25519
 private/
 signer-ed25519
diff --git a/dev/asn1-wrap-ed25519.go b/dev/asn1-wrap-ed25519.go
new file mode 100644
index 0000000..7fa103b
--- /dev/null
+++ b/dev/asn1-wrap-ed25519.go
@@ -0,0 +1,70 @@
+/*
+ * MacGDBp
+ * Copyright (c) 2020, Blue Static <https://www.bluestatic.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License as published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
+ * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program; if not,
+ * write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+
+/*
+asn1-wrap-ed25519 takes a raw private key from signer-ed25519 and reencodes it as PEM PKCS8 (ASN.1).
+
+The raw keys generated by signer-ed25519 are not compatible with the OpenSSL
+command. By storing it in PKCS8, the keys can be used with openssl commands.
+
+Usage:
+
+	./signer-ed25519 -new-key > out.key
+	./asn1-wrap-ed25519 out.key > out-wrapped.key
+*/
+package main
+
+import (
+	"crypto/ed25519"
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+	"io/ioutil"
+	"os"
+)
+
+func main() {
+	keyfile := os.Args[1]
+
+	keyPemData, err := ioutil.ReadFile(keyfile)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to read key: %v\n", err)
+		os.Exit(1)
+	}
+
+	keyPem, _ := pem.Decode(keyPemData)
+	if keyPem == nil {
+		fmt.Fprintf(os.Stderr, "Failed to decode PEM: %v\n", err)
+		os.Exit(1)
+	}
+
+	key := ed25519.PrivateKey(keyPem.Bytes)
+
+	asn1Bytes, err := x509.MarshalPKCS8PrivateKey(key)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to ASN.1 encode key: %v\n", err)
+		os.Exit(1)
+	}
+
+	asn1Pem := &pem.Block{Type: "PRIVATE KEY", Bytes: asn1Bytes}
+
+	err = pem.Encode(os.Stdout, asn1Pem)
+	if err != nil {
+		fmt.Println("Failed to PEM-encode ASN.1 key: %v\n", err)
+		os.Exit(1)
+	}
+}
-- 
2.22.5