From 650c913930a5706e96d9ad31eb2f4102cc387f02 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mika=C3=ABl=20Cluseau?= <mikael.cluseau@gmail.com>
Date: Sun, 17 Dec 2023 15:33:56 +0100
Subject: [PATCH] ssh: load more host key formats than rsa

---
 bootstrap.go |  1 +
 ssh.go       | 27 +++++++++++++++++++--------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/bootstrap.go b/bootstrap.go
index 7131bdf..b4ad15e 100644
--- a/bootstrap.go
+++ b/bootstrap.go
@@ -133,6 +133,7 @@ func setUserPass(user, passwordHash string) {
 		p := strings.Split(line, ":")
 		if len(p) < 2 || p[0] != user {
 			buf.WriteString(line)
+			buf.WriteByte('\n')
 			continue
 		}
 
diff --git a/ssh.go b/ssh.go
index b053c89..46f212b 100644
--- a/ssh.go
+++ b/ssh.go
@@ -23,18 +23,29 @@ func startSSH(cfg *config.Config) {
 		PublicKeyCallback: sshCheckPubkey,
 	}
 
-	pkBytes, err := os.ReadFile("/id_rsa") // TODO configurable
-	if err != nil {
-		fatalf("ssh: failed to load private key: %v", err)
+	hostKeyLoaded := false
+
+	for _, format := range []string{"rsa", "dsa", "ecdsa", "ed25519"} {
+		pkBytes, err := os.ReadFile("/id_" + format)
+		if err != nil {
+			log.Printf("ssh : failed to load %s host key: %v", format, err)
+			continue
+		}
+
+		pk, err := ssh.ParsePrivateKey(pkBytes)
+		if err != nil {
+			log.Printf("ssh: failed to parse %s host key: %v", format, err)
+			continue
+		}
+
+		sshConfig.AddHostKey(pk)
+		hostKeyLoaded = true
 	}
 
-	pk, err := ssh.ParsePrivateKey(pkBytes)
-	if err != nil {
-		fatalf("ssh: failed to parse private key: %v", err)
+	if !hostKeyLoaded {
+		fatalf("ssh: failed to load any host key")
 	}
 
-	sshConfig.AddHostKey(pk)
-
 	sshBind := ":22" // TODO configurable
 	listener, err := net.Listen("tcp", sshBind)
 	if err != nil {