Refine auto-keypair regen functionality. Complain loudly if only one of (cert.pem, key.pem) exists.

gencert.go

@@ -55,7 +55,7 @@ func GenerateSelfSignedCert(certpath, keypath string) (err error) {
 		Bytes: keybuf,
 	}
 
-	certfn := filepath.Join(Args.DataDir, "cert")
+	certfn := filepath.Join(Args.DataDir, "cert.pem")
 	file, err := os.OpenFile(certfn, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0700)
 	if err != nil {
 		return err
@@ -66,7 +66,7 @@ func GenerateSelfSignedCert(certpath, keypath string) (err error) {
 		return err
 	}
 
-	keyfn := filepath.Join(Args.DataDir, "key")
+	keyfn := filepath.Join(Args.DataDir, "key.pem")
 	file, err = os.OpenFile(keyfn, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0700)
 	if err != nil {
 		return err

grumble.go

@@ -76,23 +76,44 @@ func main() {
 	// These are used as the default certificate of all virtual servers
 	// and the SSH admin console, but can be overridden using the "key"
 	// and "cert" arguments to Grumble.
-	certFn := filepath.Join(Args.DataDir, "cert")
-	keyFn := filepath.Join(Args.DataDir, "key")
+	certFn := filepath.Join(Args.DataDir, "cert.pem")
+	keyFn := filepath.Join(Args.DataDir, "key.pem")
 	shouldRegen := false
 	if Args.RegenKeys {
 		shouldRegen = true
 	} else {
-		files := []string{certFn, keyFn}
-		for _, fn := range files {
-			_, err := os.Stat(fn)
-			if err != nil {
-				if e, ok := err.(*os.PathError); ok {
-					if e.Err == os.ENOENT {
-						shouldRegen = true
-					}
+		// OK. Here's the idea:  We check for the existence of the cert.pem
+		// and key.pem files in the data directory on launch. Although these
+		// might be deleted later (and this check could be deemed useless),
+		// it's simply here to be convenient for admins.
+		hasKey := true
+		hasCert := true
+		_, err = os.Stat(certFn)
+		if err != nil {
+			if e, ok := err.(*os.PathError); ok {
+				if e.Err == os.ENOENT {
+					hasCert = false
 				}
 			}
 		}
+		_, err = os.Stat(keyFn)
+		if err != nil {
+			if e, ok := err.(*os.PathError); ok {
+				if e.Err == os.ENOENT {
+					hasKey = false
+				}
+			}
+		}
+		if !hasCert && !hasKey {
+			shouldRegen = true
+		} else if !hasCert || !hasKey {
+			if !hasCert {
+				log.Fatal("Grumble could not find its default certificate (cert.pem)")
+			}
+			if !hasKey {
+				log.Fatal("Grumble could not find its default private key (key.pem)")
+			}
+		}
 	}
 	if shouldRegen {
 		log.Printf("Generating 4096-bit RSA keypair for self-signed certificate...")
@@ -143,6 +164,9 @@ func main() {
 		return
 	}
 
+	// Run the SSH admin console.
+	RunSSH()
+
 	// Read all entries of the data directory.
 	// We need these to load our virtual servers.
 	names, err := dataDir.Readdirnames(-1)
@@ -189,9 +213,6 @@ func main() {
 		go s.ListenAndMurmur()
 	}
 
-	// Run the SSH admin console.
-	go RunSSH()
-
 	// If any servers were loaded, launch the signal
 	// handler goroutine and sleep...
 	if len(servers) > 0 {

server.go

@@ -1190,7 +1190,9 @@ func (s *Server) ListenAndMurmur() {
 	go s.SendUDP()
 
 	// Create a new listening TLS socket.
-	cert, err := tls.LoadX509KeyPair(filepath.Join(Args.DataDir, "cert"), filepath.Join(Args.DataDir, "key"))
+	certFn := filepath.Join(Args.DataDir, "cert.pem")
+	keyFn := filepath.Join(Args.DataDir, "key.pem")
+	cert, err := tls.LoadX509KeyPair(certFn, keyFn)
 	if err != nil {
 		s.Printf("Unable to load x509 key pair: %v", err)
 		return

ssh.go

@@ -72,7 +72,7 @@ func RunSSH() {
 		"<id> <key> <value>",
 		"Get a config value for the server with the given id")
 
-	pemBytes, err := ioutil.ReadFile(filepath.Join(Args.DataDir, "key"))
+	pemBytes, err := ioutil.ReadFile(filepath.Join(Args.DataDir, "key.pem"))
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -89,32 +89,34 @@ func RunSSH() {
 
 	log.Printf("Listening for SSH connections on '%v'", Args.SshAddr)
 
-	for {
-		conn, err := listener.Accept()
-		if err != nil {
-			log.Fatalf("ssh: unable to accept incoming connection: %v", err)
-		}
-
-		err = conn.Handshake()
-		if err == io.EOF {
-			continue
-		} else if err != nil {
-			log.Fatalf("ssh: unable to perform handshake: %v", err)
-		}
-
-		go func() {
-			for {
-				channel, err := conn.Accept()
-				if err == io.EOF {
-					return
-				} else if err != nil {
-					log.Fatalf("ssh: unable to accept channel: %v", err)
-				}
-
-				go handleChannel(channel)
+	go func() {
+		for {
+			conn, err := listener.Accept()
+			if err != nil {
+				log.Fatalf("ssh: unable to accept incoming connection: %v", err)
 			}
-		}()
-	}
+
+			err = conn.Handshake()
+			if err == io.EOF {
+				continue
+			} else if err != nil {
+				log.Fatalf("ssh: unable to perform handshake: %v", err)
+			}
+
+			go func() {
+				for {
+					channel, err := conn.Accept()
+					if err == io.EOF {
+						return
+					} else if err != nil {
+						log.Fatalf("ssh: unable to accept channel: %v", err)
+					}
+
+					go handleChannel(channel)
+				}
+			}()
+		}
+	}()
 }
 
 func handleChannel(channel ssh.Channel) {