begin working on host entry

main.go

@@ -5,6 +5,7 @@ import (
 	"flag"
 	"fmt"
 	"lux/crypto"
+	"lux/host"
 	"lux/node"
 	"lux/proto"
 	"lux/rpc"
@@ -322,8 +323,94 @@ signaling:
 	node.Stop()
 }
 
-func hostMain() {
+type HostCommand struct {
+	XMLName    xml.Name `xml:"command"`
+	Executable string   `xml:",innerxml"`
+}
 
+type HostConfig struct {
+	XMLName  xml.Name `xml:"host"`
+	KeyStore string   `xml:"keystore"`
+	ID       string   `xml:"id"`
+	Hostname string   `xml:"hostname"`
+
+	Heartbeat int `xml:"heartbeat"`
+
+	Options []struct {
+		XMLName xml.Name `xml:"option"`
+		Type    string   `xml:"type,attr"`
+
+		WAN struct {
+			XMLName xml.Name `xml:"wan"`
+
+			Method string `xml:"method,attr"`
+
+			Addr4 string `xml:"addr4"`
+			Addr6 string `xml:"addr6"`
+
+			Command HostCommand `xml:"command"`
+		} `xml:"wan"`
+	} `xml:"option"`
+
+	Nodes []struct {
+		XMLName  xml.Name `xml:"node"`
+		ID       string   `xml:"id"`
+		Exterior string   `xml:"exterior"`
+	} `xml:"node"`
+}
+
+func hostMain() {
+	xmlBytes, err := os.ReadFile(configPath)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to open config: %v\n", err)
+		os.Exit(1)
+	}
+
+	var config HostConfig
+	if err := xml.Unmarshal(xmlBytes, &config); err != nil {
+		fmt.Fprintf(os.Stderr, "failed to parse host config: %v\n", err)
+		os.Exit(1)
+	}
+
+	ks := crypto.NewLuxKeyStore(config.KeyStore)
+	if err := ks.Load(); err != nil {
+		fmt.Fprintf(os.Stderr, "failed to load keystore: %v\n", err)
+		os.Exit(1)
+	}
+
+	hostId, err := proto.ParseLuxID(config.ID)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to parse host ID: %v\n", err)
+		os.Exit(1)
+	}
+	hostKey, ok := ks.Get(hostId)
+	if !ok {
+		fmt.Fprintln(os.Stderr, "host key is not present in keystore!")
+		os.Exit(1)
+	}
+
+	if config.Hostname == "" {
+		fmt.Fprintln(os.Stderr, "no hostname specified!")
+		os.Exit(1)
+	}
+
+	// daemonize if needed
+	if daemonize {
+		becomeDaemon()
+	}
+
+	// create host
+	host := host.NewLuxHost(config.Hostname, hostKey, ks)
+
+	// populate option providers
+
+	// start host
+
+	// start heartbeat timer
+
+	// handle signals in main thread
+
+	// stop host
 }
 
 var rpcPath string