✨ feat: generate both RSA and Ed25519 host keys

src/hostKeys.ts

@@ -3,25 +3,37 @@ import path from "path";
 import crypto from "crypto";
 import sshpk from "sshpk";
 
-export function ensureHostKeys(configDir: string): void {
-    const keyPath = path.join(configDir, "id_rsa");
-    if (fs.existsSync(keyPath)) return;
+function generateAndSave(keyPath: string, type: "rsa" | "ed25519"): void {
+    console.log(`Generating ${type} host key...`);
 
-    console.log("Generating host keys...");
-    const key = crypto.generateKeyPairSync("rsa", {
+    const { privateKey } =
+        type === "rsa"
+            ? crypto.generateKeyPairSync("rsa", {
                   modulusLength: 4096,
-        publicKeyEncoding: {
-            type: "pkcs1",
-            format: "pem",
-        },
-        privateKeyEncoding: {
-            type: "pkcs8",
-            format: "pem",
-        },
+                  publicKeyEncoding: { type: "pkcs1", format: "pem" },
+                  privateKeyEncoding: { type: "pkcs8", format: "pem" },
+              })
+            : crypto.generateKeyPairSync("ed25519", {
+                  publicKeyEncoding: { type: "spki", format: "pem" },
+                  privateKeyEncoding: { type: "pkcs8", format: "pem" },
               });
 
-    const keyPem = sshpk.parsePrivateKey(key.privateKey, "pem");
-    const keyParsed = sshpk.parsePrivateKey(keyPem.toString("pem"));
+    const parsed = sshpk.parsePrivateKey(privateKey, "pem");
+    fs.writeFileSync(keyPath, parsed.toString("openssh"), { mode: 0o600 });
+    fs.chmodSync(keyPath, 0o600);
+}
 
-    fs.writeFileSync(keyPath, keyParsed.toString("openssh"));
+export function ensureHostKeys(configDir: string): Buffer[] {
+    const keys: Array<{ file: string; type: "rsa" | "ed25519" }> = [
+        { file: "id_rsa", type: "rsa" },
+        { file: "id_ed25519", type: "ed25519" },
+    ];
+
+    return keys.map(({ file, type }) => {
+        const keyPath = path.join(configDir, file);
+        if (!fs.existsSync(keyPath)) {
+            generateAndSave(keyPath, type);
+        }
+        return fs.readFileSync(keyPath);
+    });
 }