refactor(network): rewrite network and timesync component

cloud.go

@@ -311,11 +311,15 @@ func runWebsocketClient() error {
 		},
 	})
 
-	// get the request id from the response header
+	var connectionId string
-	connectionId := resp.Header.Get("X-Request-ID")
+	if resp != nil {
-	if connectionId == "" {
+		// get the request id from the response header
-		connectionId = resp.Header.Get("Cf-Ray")
+		connectionId = resp.Header.Get("X-Request-ID")
+		if connectionId == "" {
+			connectionId = resp.Header.Get("Cf-Ray")
+		}
 	}
+
 	if connectionId == "" {
 		connectionId = uuid.New().String()
 		scopedLogger.Warn().
@@ -457,7 +461,7 @@ func RunWebsocketClient() {
 		}
 
 		// If the system time is not synchronized, the API request will fail anyway because the TLS handshake will fail.
-		if isTimeSyncNeeded() && !timeSyncSuccess {
+		if isTimeSyncNeeded() && !timeSync.IsSyncSuccess() {
 			cloudLogger.Warn().Msg("system time is not synced, will retry in 3 seconds")
 			time.Sleep(3 * time.Second)
 			continue

config.go

@@ -134,7 +134,7 @@ func LoadConfig() {
 	defer configLock.Unlock()
 
 	if config != nil {
-		logger.Info().Msg("config already loaded, skipping")
+		logger.Debug().Msg("config already loaded, skipping")
 		return
 	}
 
@@ -167,6 +167,8 @@ func LoadConfig() {
 	config = &loadedConfig
 
 	rootLogger.UpdateLogLevel()
+
+	logger.Info().Str("path", configPath).Msg("config loaded")
 }
 
 func SaveConfig() error {

display.go

@@ -48,7 +48,7 @@ func switchToScreenIfDifferent(screenName string) {
 }
 
 func updateDisplay() {
-	updateLabelIfChanged("ui_Home_Content_Ip", networkState.IPv4)
+	updateLabelIfChanged("ui_Home_Content_Ip", networkState.IPv4String())
 	if usbState == "configured" {
 		updateLabelIfChanged("ui_Home_Footer_Usb_Status_Label", "Connected")
 		_, _ = CallCtrlAction("lv_obj_set_state", map[string]interface{}{"obj": "ui_Home_Footer_Usb_Status_Label", "state": "LV_STATE_DEFAULT"})
@@ -64,7 +64,7 @@ func updateDisplay() {
 		_, _ = CallCtrlAction("lv_obj_set_state", map[string]interface{}{"obj": "ui_Home_Footer_Hdmi_Status_Label", "state": "LV_STATE_USER_2"})
 	}
 	updateLabelIfChanged("ui_Home_Header_Cloud_Status_Label", fmt.Sprintf("%d active", actionSessions))
-	if networkState.Up {
+	if networkState.IsUp() {
 		switchToScreenIfDifferent("ui_Home_Screen")
 	} else {
 		switchToScreenIfDifferent("ui_No_Network_Screen")
@@ -94,7 +94,7 @@ func requestDisplayUpdate() {
 
 func updateStaticContents() {
 	//contents that never change
-	updateLabelIfChanged("ui_Home_Content_Mac", networkState.MAC)
+	updateLabelIfChanged("ui_Home_Content_Mac", networkState.MACString())
 	systemVersion, appVersion, err := GetLocalVersion()
 	if err == nil {
 		updateLabelIfChanged("ui_About_Content_Operating_System_Version_ContentLabel", systemVersion.String())

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/coder/websocket v1.8.13
 	github.com/coreos/go-oidc/v3 v3.11.0
 	github.com/creack/pty v1.1.23
+	github.com/fsnotify/fsnotify v1.9.0
 	github.com/gin-contrib/logger v1.2.5
 	github.com/gin-gonic/gin v1.10.0
 	github.com/google/uuid v1.6.0

go.sum

@@ -28,6 +28,8 @@ github.com/creack/pty v1.1.23/go.mod h1:08sCNb52WyoAwi2QDyzUCTgcvVFhUzewun7wtTfv
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fsnotify/fsnotify v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
+github.com/fsnotify/fsnotify v1.9.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
 github.com/gabriel-vasile/mimetype v1.4.8 h1:FfZ3gj38NjllZIeJAmMhr+qKL8Wu+nOoI3GqacKw1NM=
 github.com/gabriel-vasile/mimetype v1.4.8/go.mod h1:ByKUIKGjh1ODkGM1asKUbQZOLGrPjydw3hYPU2YU9t8=
 github.com/gin-contrib/logger v1.2.5 h1:qVQI4omayQecuN4zX9ZZnsOq7w9J/ZLds3J/FMn8ypM=

internal/timesync/http.go

@@ -0,0 +1,54 @@
+package timesync
+
+import (
+	"net/http"
+	"time"
+)
+
+func queryHttpTime(
+	url string,
+	timeout time.Duration,
+) (now *time.Time, err error, response *http.Response) {
+	client := http.Client{
+		Timeout: timeout,
+	}
+	resp, err := client.Head(url)
+	if err != nil {
+		return nil, err, nil
+	}
+	dateStr := resp.Header.Get("Date")
+	parsedTime, err := time.Parse(time.RFC1123, dateStr)
+	if err != nil {
+		return nil, err, resp
+	}
+	return &parsedTime, nil, resp
+}
+
+func (t *TimeSync) queryAllHttpTime() (now *time.Time) {
+	for _, url := range t.httpUrls {
+		now, err, response := queryHttpTime(url, timeSyncTimeout)
+
+		var status string
+		if response != nil {
+			status = response.Status
+		}
+
+		scopedLogger := t.l.With().
+			Str("http_url", url).
+			Str("status", status).
+			Logger()
+
+		if err == nil {
+			scopedLogger.Info().
+				Str("time", now.Format(time.RFC3339)).
+				Msg("HTTP server returned time")
+			return now
+		} else {
+			scopedLogger.Error().
+				Str("error", err.Error()).
+				Msg("failed to query HTTP server")
+		}
+	}
+
+	return nil
+}

internal/timesync/ntp.go

@@ -0,0 +1,42 @@
+package timesync
+
+import (
+	"time"
+
+	"github.com/beevik/ntp"
+)
+
+func (t *TimeSync) queryNetworkTime() (now *time.Time) {
+	for _, server := range t.ntpServers {
+		now, err, response := queryNtpServer(server, timeSyncTimeout)
+
+		scopedLogger := t.l.With().
+			Str("server", server).
+			Logger()
+
+		if err == nil {
+			scopedLogger.Info().
+				Str("time", now.Format(time.RFC3339)).
+				Str("reference", response.ReferenceString()).
+				Str("rtt", response.RTT.String()).
+				Str("clockOffset", response.ClockOffset.String()).
+				Uint8("stratum", response.Stratum).
+				Msg("NTP server returned time")
+			return now
+		} else {
+			scopedLogger.Error().
+				Str("error", err.Error()).
+				Msg("failed to query NTP server")
+		}
+	}
+
+	return nil
+}
+
+func queryNtpServer(server string, timeout time.Duration) (now *time.Time, err error, response *ntp.Response) {
+	resp, err := ntp.QueryWithOptions(server, ntp.QueryOptions{Timeout: timeout})
+	if err != nil {
+		return nil, err, nil
+	}
+	return &resp.Time, nil, resp
+}

internal/timesync/rtc.go

@@ -0,0 +1,26 @@
+package timesync
+
+import (
+	"fmt"
+	"os"
+)
+
+var (
+	rtcDeviceSearchPaths = []string{
+		"/dev/rtc",
+		"/dev/rtc0",
+		"/dev/rtc1",
+		"/dev/misc/rtc",
+		"/dev/misc/rtc0",
+		"/dev/misc/rtc1",
+	}
+)
+
+func getRtcDevicePath() (string, error) {
+	for _, path := range rtcDeviceSearchPaths {
+		if _, err := os.Stat(path); err == nil {
+			return path, nil
+		}
+	}
+	return "", fmt.Errorf("rtc device not found")
+}

internal/timesync/rtc_linux.go

@@ -0,0 +1,103 @@
+//go:build linux
+
+package timesync
+
+import (
+	"fmt"
+	"os"
+	"time"
+
+	"golang.org/x/sys/unix"
+)
+
+func TimetoRtcTime(t time.Time) unix.RTCTime {
+	return unix.RTCTime{
+		Sec:   int32(t.Second()),
+		Min:   int32(t.Minute()),
+		Hour:  int32(t.Hour()),
+		Mday:  int32(t.Day()),
+		Mon:   int32(t.Month() - 1),
+		Year:  int32(t.Year() - 1900),
+		Wday:  int32(0),
+		Yday:  int32(0),
+		Isdst: int32(0),
+	}
+}
+
+func RtcTimetoTime(t unix.RTCTime) time.Time {
+	return time.Date(
+		int(t.Year)+1900,
+		time.Month(t.Mon+1),
+		int(t.Mday),
+		int(t.Hour),
+		int(t.Min),
+		int(t.Sec),
+		0,
+		time.UTC,
+	)
+}
+
+func (t *TimeSync) getRtcDevice() (*os.File, error) {
+	if t.rtcDevice == nil {
+		file, err := os.OpenFile(t.rtcDevicePath, os.O_RDWR, 0666)
+		if err != nil {
+			return nil, err
+		}
+		t.rtcDevice = file
+	}
+	return t.rtcDevice, nil
+}
+
+func (t *TimeSync) getRtcDeviceFd() (int, error) {
+	device, err := t.getRtcDevice()
+	if err != nil {
+		return 0, err
+	}
+	return int(device.Fd()), nil
+}
+
+// Read implements Read for the Linux RTC
+func (t *TimeSync) readRtcTime() (time.Time, error) {
+	fd, err := t.getRtcDeviceFd()
+	if err != nil {
+		return time.Time{}, fmt.Errorf("failed to get RTC device fd: %w", err)
+	}
+
+	rtcTime, err := unix.IoctlGetRTCTime(fd)
+	if err != nil {
+		return time.Time{}, fmt.Errorf("failed to get RTC time: %w", err)
+	}
+
+	date := RtcTimetoTime(*rtcTime)
+
+	return date, nil
+}
+
+// Set implements Set for the Linux RTC
+// ...
+// It might be not accurate as the time consumed by the system call is not taken into account
+// but it's good enough for our purposes
+func (t *TimeSync) setRtcTime(tu time.Time) error {
+	rt := TimetoRtcTime(tu)
+
+	fd, err := t.getRtcDeviceFd()
+	if err != nil {
+		return fmt.Errorf("failed to get RTC device fd: %w", err)
+	}
+
+	currentRtcTime, err := t.readRtcTime()
+	if err != nil {
+		return fmt.Errorf("failed to read RTC time: %w", err)
+	}
+
+	t.l.Info().
+		Interface("rtc_time", tu).
+		Str("offset", tu.Sub(currentRtcTime).String()).
+		Msg("set rtc time")
+
+	if err := unix.IoctlSetRTCTime(fd, &rt); err != nil {
+		return fmt.Errorf("failed to set RTC time: %w", err)
+	}
+
+	return nil
+}

internal/timesync/rtc_notlinux.go

@@ -0,0 +1,16 @@
+//go:build !linux
+
+package timesync
+
+import (
+	"errors"
+	"time"
+)
+
+func (t *TimeSync) readRtcTime() (time.Time, error) {
+	return time.Now(), nil
+}
+
+func (t *TimeSync) setRtcTime(tu time.Time) error {
+	return errors.New("not supported")
+}

internal/timesync/timesync.go

@@ -0,0 +1,151 @@
+package timesync
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"sync"
+	"time"
+
+	"github.com/rs/zerolog"
+)
+
+const (
+	timeSyncRetryStep     = 5 * time.Second
+	timeSyncRetryMaxInt   = 1 * time.Minute
+	timeSyncWaitNetChkInt = 100 * time.Millisecond
+	timeSyncWaitNetUpInt  = 3 * time.Second
+	timeSyncInterval      = 1 * time.Hour
+	timeSyncTimeout       = 2 * time.Second
+)
+
+var (
+	timeSyncRetryInterval = 0 * time.Second
+	defaultNTPServers     = []string{
+		"time.cloudflare.com",
+		"time.apple.com",
+	}
+)
+
+type TimeSync struct {
+	syncLock *sync.Mutex
+	l        *zerolog.Logger
+
+	ntpServers []string
+	httpUrls   []string
+
+	rtcDevicePath string
+	rtcDevice     *os.File
+	rtcLock       *sync.Mutex
+
+	syncSuccess bool
+
+	preCheckFunc func() (bool, error)
+}
+
+func NewTimeSync(
+	precheckFunc func() (bool, error),
+	ntpServers []string,
+	httpUrls []string,
+	logger *zerolog.Logger,
+) *TimeSync {
+	rtcDevice, err := getRtcDevicePath()
+	if err != nil {
+		logger.Error().Err(err).Msg("failed to get RTC device path")
+	} else {
+		logger.Info().Str("path", rtcDevice).Msg("RTC device found")
+	}
+
+	t := &TimeSync{
+		syncLock:      &sync.Mutex{},
+		l:             logger,
+		rtcDevicePath: rtcDevice,
+		rtcLock:       &sync.Mutex{},
+		preCheckFunc:  precheckFunc,
+		ntpServers:    ntpServers,
+		httpUrls:      httpUrls,
+	}
+
+	if t.rtcDevicePath != "" {
+		rtcTime, _ := t.readRtcTime()
+		t.l.Info().Interface("rtc_time", rtcTime).Msg("read RTC time")
+	}
+
+	return t
+}
+
+func (t *TimeSync) doTimeSync() {
+	for {
+		if ok, err := t.preCheckFunc(); !ok {
+			if err != nil {
+				t.l.Error().Err(err).Msg("pre-check failed")
+			}
+			time.Sleep(timeSyncWaitNetChkInt)
+			continue
+		}
+
+		t.l.Info().Msg("syncing system time")
+		start := time.Now()
+		err := t.Sync()
+		if err != nil {
+			t.l.Error().Str("error", err.Error()).Msg("failed to sync system time")
+
+			// retry after a delay
+			timeSyncRetryInterval += timeSyncRetryStep
+			time.Sleep(timeSyncRetryInterval)
+			// reset the retry interval if it exceeds the max interval
+			if timeSyncRetryInterval > timeSyncRetryMaxInt {
+				timeSyncRetryInterval = 0
+			}
+
+			continue
+		}
+		t.syncSuccess = true
+		t.l.Info().Str("now", time.Now().Format(time.RFC3339)).
+			Str("time_taken", time.Since(start).String()).
+			Msg("time sync successful")
+
+		time.Sleep(timeSyncInterval) // after the first sync is done
+	}
+}
+
+func (t *TimeSync) Sync() error {
+	var now *time.Time
+	now = t.queryNetworkTime()
+	if now == nil {
+		now = t.queryAllHttpTime()
+	}
+
+	if now == nil {
+		return fmt.Errorf("failed to get time from any source")
+	}
+
+	err := t.setSystemTime(*now)
+	if err != nil {
+		return fmt.Errorf("failed to set system time: %w", err)
+	}
+
+	return nil
+}
+
+func (t *TimeSync) IsSyncSuccess() bool {
+	return t.syncSuccess
+}
+
+func (t *TimeSync) Start() {
+	go t.doTimeSync()
+}
+
+func (t *TimeSync) setSystemTime(now time.Time) error {
+	nowStr := now.Format("2006-01-02 15:04:05")
+	output, err := exec.Command("date", "-s", nowStr).CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("failed to run date -s: %w, %s", err, string(output))
+	}
+
+	if t.rtcDevicePath != "" {
+		return t.setRtcTime(now)
+	}
+
+	return nil
+}

internal/udhcpc/options.go

@@ -0,0 +1,12 @@
+package udhcpc
+
+func (u *DHCPClient) GetNtpServers() []string {
+	if u.lease == nil {
+		return nil
+	}
+	servers := make([]string, len(u.lease.NTPServers))
+	for i, server := range u.lease.NTPServers {
+		servers[i] = server.String()
+	}
+	return servers
+}

internal/udhcpc/parser.go

@@ -0,0 +1,150 @@
+package udhcpc
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net"
+	"reflect"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type Lease struct {
+	// from https://udhcp.busybox.net/README.udhcpc
+	IPAddress         net.IP        `env:"ip" json:"ip"`                               // The obtained IP
+	Netmask           net.IP        `env:"subnet" json:"netmask"`                      // The assigned subnet mask
+	Broadcast         net.IP        `env:"broadcast" json:"broadcast"`                 // The broadcast address for this network
+	TTL               int           `env:"ipttl" json:"ttl,omitempty"`                 // The TTL to use for this network
+	MTU               int           `env:"mtu" json:"mtu,omitempty"`                   // The MTU to use for this network
+	HostName          string        `env:"hostname" json:"hostname,omitempty"`         // The assigned hostname
+	Domain            string        `env:"domain" json:"domain,omitempty"`             // The domain name of the network
+	BootPNextServer   net.IP        `env:"siaddr" json:"bootp_next_server,omitempty"`  // The bootp next server option
+	BootPServerName   string        `env:"sname" json:"bootp_server_name,omitempty"`   // The bootp server name option
+	BootPFile         string        `env:"boot_file" json:"bootp_file,omitempty"`      // The bootp boot file option
+	Timezone          string        `env:"timezone" json:"timezone,omitempty"`         // Offset in seconds from UTC
+	Routers           []net.IP      `env:"router" json:"routers,omitempty"`            // A list of routers
+	DNS               []net.IP      `env:"dns" json:"dns_servers,omitempty"`           // A list of DNS servers
+	NTPServers        []net.IP      `env:"ntpsrv" json:"ntp_servers,omitempty"`        // A list of NTP servers
+	LPRServers        []net.IP      `env:"lprsvr" json:"lpr_servers,omitempty"`        // A list of LPR servers
+	TimeServers       []net.IP      `env:"timesvr" json:"_time_servers,omitempty"`     // A list of time servers (obsolete)
+	IEN116NameServers []net.IP      `env:"namesvr" json:"_name_servers,omitempty"`     // A list of IEN 116 name servers (obsolete)
+	LogServers        []net.IP      `env:"logsvr" json:"_log_servers,omitempty"`       // A list of MIT-LCS UDP log servers (obsolete)
+	CookieServers     []net.IP      `env:"cookiesvr" json:"_cookie_servers,omitempty"` // A list of RFC 865 cookie servers (obsolete)
+	WINSServers       []net.IP      `env:"wins" json:"_wins_servers,omitempty"`        // A list of WINS servers
+	SwapServer        net.IP        `env:"swapsvr" json:"_swap_server,omitempty"`      // The IP address of the client's swap server
+	BootSize          int           `env:"bootsize" json:"bootsize,omitempty"`         // The length in 512 octect blocks of the bootfile
+	RootPath          string        `env:"rootpath" json:"root_path,omitempty"`        // The path name of the client's root disk
+	LeaseTime         time.Duration `env:"lease" json:"lease,omitempty"`               // The lease time, in seconds
+	DHCPType          string        `env:"dhcptype" json:"dhcp_type,omitempty"`        // DHCP message type (safely ignored)
+	ServerID          string        `env:"serverid" json:"server_id,omitempty"`        // The IP of the server
+	Message           string        `env:"message" json:"reason,omitempty"`            // Reason for a DHCPNAK
+	TFTPServerName    string        `env:"tftp" json:"tftp,omitempty"`                 // The TFTP server name
+	BootFileName      string        `env:"bootfile" json:"bootfile,omitempty"`         // The boot file name
+	isEmpty           map[string]bool
+}
+
+func (l *Lease) setIsEmpty(m map[string]bool) {
+	l.isEmpty = m
+}
+
+func (l *Lease) IsEmpty(key string) bool {
+	return l.isEmpty[key]
+}
+
+func (l *Lease) ToJSON() string {
+	json, err := json.Marshal(l)
+	if err != nil {
+		return ""
+	}
+	return string(json)
+}
+
+func UnmarshalDHCPCLease(lease *Lease, str string) error {
+	// parse the lease file as a map
+	data := make(map[string]string)
+	for _, line := range strings.Split(str, "\n") {
+		line = strings.TrimSpace(line)
+		// skip empty lines and comments
+		if line == "" || strings.HasPrefix(line, "#") {
+			continue
+		}
+
+		parts := strings.SplitN(line, "=", 2)
+		if len(parts) != 2 {
+			log.Printf("invalid line: %s", line)
+			continue
+		}
+
+		key := strings.TrimSpace(parts[0])
+		value := strings.TrimSpace(parts[1])
+
+		data[key] = value
+	}
+
+	// now iterate over the lease struct and set the values
+	leaseType := reflect.TypeOf(lease).Elem()
+	leaseValue := reflect.ValueOf(lease).Elem()
+
+	valuesParsed := make(map[string]bool)
+
+	for i := 0; i < leaseType.NumField(); i++ {
+		field := leaseValue.Field(i)
+
+		// get the env tag
+		key := leaseType.Field(i).Tag.Get("env")
+		if key == "" {
+			continue
+		}
+
+		valuesParsed[key] = false
+
+		// get the value from the data map
+		value, ok := data[key]
+		if !ok || value == "" {
+			continue
+		}
+
+		switch field.Interface().(type) {
+		case string:
+			field.SetString(value)
+		case int:
+			val, err := strconv.Atoi(value)
+			if err != nil {
+				continue
+			}
+			field.SetInt(int64(val))
+		case time.Duration:
+			val, err := time.ParseDuration(value + "s")
+			if err != nil {
+				continue
+			}
+			field.Set(reflect.ValueOf(val))
+		case net.IP:
+			ip := net.ParseIP(value)
+			if ip == nil {
+				continue
+			}
+			field.Set(reflect.ValueOf(ip))
+		case []net.IP:
+			val := make([]net.IP, 0)
+			for _, ipStr := range strings.Fields(value) {
+				ip := net.ParseIP(ipStr)
+				if ip == nil {
+					continue
+				}
+				val = append(val, ip)
+			}
+			field.Set(reflect.ValueOf(val))
+		default:
+			return fmt.Errorf("unsupported field `%s` type: %s", key, field.Type().String())
+		}
+
+		valuesParsed[key] = true
+	}
+
+	lease.setIsEmpty(valuesParsed)
+
+	return nil
+}

internal/udhcpc/parser_test.go

@@ -0,0 +1,74 @@
+package udhcpc
+
+import (
+	"testing"
+	"time"
+)
+
+func TestUnmarshalDHCPCLease(t *testing.T) {
+	lease := &Lease{}
+	err := UnmarshalDHCPCLease(lease, `
+# generated @ Mon Jan  4 19:31:53 UTC 2021
+#  19:31:53 up 0 min,  0 users,  load average: 0.72, 0.14, 0.04
+# the date might be inaccurate if the clock is not set
+ip=192.168.0.240
+siaddr=192.168.0.1
+sname=
+boot_file=
+subnet=255.255.255.0
+timezone=
+router=192.168.0.1
+timesvr=
+namesvr=
+dns=172.19.53.2
+logsvr=
+cookiesvr=
+lprsvr=
+hostname=
+bootsize=
+domain=
+swapsvr=
+rootpath=
+ipttl=
+mtu=
+broadcast=
+ntpsrv=162.159.200.123
+wins=
+lease=172800
+dhcptype=
+serverid=192.168.0.1
+message=
+tftp=
+bootfile=
+	`)
+	if lease.IPAddress.String() != "192.168.0.240" {
+		t.Fatalf("expected ip to be 192.168.0.240, got %s", lease.IPAddress.String())
+	}
+	if lease.Netmask.String() != "255.255.255.0" {
+		t.Fatalf("expected netmask to be 255.255.255.0, got %s", lease.Netmask.String())
+	}
+	if len(lease.Routers) != 1 {
+		t.Fatalf("expected 1 router, got %d", len(lease.Routers))
+	}
+	if lease.Routers[0].String() != "192.168.0.1" {
+		t.Fatalf("expected router to be 192.168.0.1, got %s", lease.Routers[0].String())
+	}
+	if len(lease.NTPServers) != 1 {
+		t.Fatalf("expected 1 timeserver, got %d", len(lease.NTPServers))
+	}
+	if lease.NTPServers[0].String() != "162.159.200.123" {
+		t.Fatalf("expected timeserver to be 162.159.200.123, got %s", lease.NTPServers[0].String())
+	}
+	if len(lease.DNS) != 1 {
+		t.Fatalf("expected 1 dns, got %d", len(lease.DNS))
+	}
+	if lease.DNS[0].String() != "172.19.53.2" {
+		t.Fatalf("expected dns to be 172.19.53.2, got %s", lease.DNS[0].String())
+	}
+	if lease.LeaseTime != 172800*time.Second {
+		t.Fatalf("expected lease time to be 172800 seconds, got %d", lease.LeaseTime)
+	}
+	if err != nil {
+		t.Fatal(err)
+	}
+}

internal/udhcpc/proc.go

@@ -0,0 +1,212 @@
+package udhcpc
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
+)
+
+func readFileNoStat(filename string) ([]byte, error) {
+	const maxBufferSize = 1024 * 1024
+
+	f, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	reader := io.LimitReader(f, maxBufferSize)
+	return io.ReadAll(reader)
+}
+
+func toCmdline(path string) ([]string, error) {
+	data, err := readFileNoStat(path)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(data) < 1 {
+		return []string{}, nil
+	}
+
+	return strings.Split(string(bytes.TrimRight(data, "\x00")), "\x00"), nil
+}
+
+func (p *DHCPClient) findUdhcpcProcess() (int, error) {
+	// read procfs for udhcpc processes
+	// we do not use procfs.AllProcs() because we want to avoid the overhead of reading the entire procfs
+	processes, err := os.ReadDir("/proc")
+	if err != nil {
+		return 0, err
+	}
+
+	// iterate over the processes
+	for _, d := range processes {
+		// check if file is numeric
+		pid, err := strconv.Atoi(d.Name())
+		if err != nil {
+			continue
+		}
+
+		// check if it's a directory
+		if !d.IsDir() {
+			continue
+		}
+
+		cmdline, err := toCmdline(filepath.Join("/proc", d.Name(), "cmdline"))
+		if err != nil {
+			continue
+		}
+
+		if len(cmdline) < 1 {
+			continue
+		}
+
+		if cmdline[0] != "udhcpc" {
+			continue
+		}
+
+		cmdlineText := strings.Join(cmdline, " ")
+
+		// check if it's a udhcpc process
+		if strings.Contains(cmdlineText, fmt.Sprintf("-i %s", p.InterfaceName)) {
+			p.logger.Debug().
+				Str("pid", d.Name()).
+				Interface("cmdline", cmdline).
+				Msg("found udhcpc process")
+			return pid, nil
+		}
+	}
+
+	return 0, errors.New("udhcpc process not found")
+}
+
+func (c *DHCPClient) getProcessPid() (int, error) {
+	var pid int
+	if c.pidFile != "" {
+		// try to read the pid file
+		pidHandle, err := os.ReadFile(c.pidFile)
+		if err != nil {
+			c.logger.Warn().Err(err).
+				Str("pidFile", c.pidFile).Msg("failed to read udhcpc pid file")
+		}
+
+		// if it exists, try to read the pid
+		if pidHandle != nil {
+			pidFromFile, err := strconv.Atoi(string(pidHandle))
+			if err != nil {
+				c.logger.Warn().Err(err).
+					Str("pidFile", c.pidFile).Msg("failed to convert pid file to int")
+			}
+			pid = pidFromFile
+		}
+	}
+
+	// if the pid is 0, try to find the pid using procfs
+	if pid == 0 {
+		newPid, err := c.findUdhcpcProcess()
+		if err != nil {
+			return 0, err
+		}
+		pid = newPid
+	}
+
+	return pid, nil
+}
+
+func (c *DHCPClient) getProcess() *os.Process {
+	pid, err := c.getProcessPid()
+	if err != nil {
+		return nil
+	}
+
+	process, err := os.FindProcess(pid)
+	if err != nil {
+		c.logger.Warn().Err(err).
+			Int("pid", pid).Msg("failed to find process")
+		return nil
+	}
+
+	return process
+}
+
+func (c *DHCPClient) GetProcess() *os.Process {
+	if c.process == nil {
+		process := c.getProcess()
+		if process == nil {
+			return nil
+		}
+		c.process = process
+	}
+
+	err := c.process.Signal(syscall.Signal(0))
+	if err != nil && errors.Is(err, os.ErrProcessDone) {
+		oldPid := c.process.Pid
+
+		c.process = nil
+		c.process = c.getProcess()
+		if c.process == nil {
+			c.logger.Error().Msg("failed to find new udhcpc process")
+			return nil
+		}
+		c.logger.Warn().
+			Int("oldPid", oldPid).
+			Int("newPid", c.process.Pid).
+			Msg("udhcpc process pid changed")
+	} else if err != nil {
+		c.logger.Warn().Err(err).
+			Int("pid", c.process.Pid).Msg("udhcpc process is not running")
+	}
+
+	return c.process
+}
+
+func (c *DHCPClient) KillProcess() error {
+	process := c.GetProcess()
+	if process == nil {
+		return nil
+	}
+
+	return process.Kill()
+}
+
+func (c *DHCPClient) ReleaseProcess() error {
+	process := c.GetProcess()
+	if process == nil {
+		return nil
+	}
+
+	return process.Release()
+}
+
+func (c *DHCPClient) signalProcess(sig syscall.Signal) error {
+	process := c.GetProcess()
+	if process == nil {
+		return nil
+	}
+
+	s := process.Signal(sig)
+	if s != nil {
+		c.logger.Warn().Err(s).
+			Int("pid", process.Pid).
+			Str("signal", sig.String()).
+			Msg("failed to signal udhcpc process")
+		return s
+	}
+
+	return nil
+}
+
+func (c *DHCPClient) Renew() error {
+	return c.signalProcess(syscall.SIGUSR1)
+}
+
+func (c *DHCPClient) Release() error {
+	return c.signalProcess(syscall.SIGUSR2)
+}

internal/udhcpc/udhcpc.go

@@ -0,0 +1,145 @@
+package udhcpc
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/fsnotify/fsnotify"
+	"github.com/rs/zerolog"
+)
+
+const (
+	DHCPLeaseFile = "/run/udhcpc.%s.info"
+	DHCPPidFile   = "/run/udhcpc.%s.pid"
+)
+
+type DHCPClient struct {
+	InterfaceName string
+	leaseFile     string
+	pidFile       string
+	lease         *Lease
+	logger        *zerolog.Logger
+	process       *os.Process
+	onLeaseChange func(lease *Lease)
+}
+
+type DHCPClientOptions struct {
+	InterfaceName string
+	PidFile       string
+	Logger        *zerolog.Logger
+	OnLeaseChange func(lease *Lease)
+}
+
+var defaultLogger = zerolog.New(os.Stdout).Level(zerolog.InfoLevel)
+
+func NewDHCPClient(options *DHCPClientOptions) *DHCPClient {
+	if options.Logger == nil {
+		options.Logger = &defaultLogger
+	}
+
+	l := options.Logger.With().Str("interface", options.InterfaceName).Logger()
+	return &DHCPClient{
+		InterfaceName: options.InterfaceName,
+		logger:        &l,
+		leaseFile:     fmt.Sprintf(DHCPLeaseFile, options.InterfaceName),
+		pidFile:       options.PidFile,
+		onLeaseChange: options.OnLeaseChange,
+	}
+}
+
+// Run starts the DHCP client and watches the lease file for changes.
+// this isn't a blocking call, and the lease file is reloaded when a change is detected.
+func (c *DHCPClient) Run() error {
+	err := c.loadLeaseFile()
+	if err != nil && !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return err
+	}
+	defer watcher.Close()
+
+	go func() {
+		for {
+			select {
+			case event, ok := <-watcher.Events:
+				if !ok {
+					return
+				}
+				if event.Has(fsnotify.Write) || event.Has(fsnotify.Create) {
+					c.logger.Debug().
+						Str("event", event.Name).
+						Msg("udhcpc lease file updated, reloading lease")
+					c.loadLeaseFile()
+				}
+			case err, ok := <-watcher.Errors:
+				if !ok {
+					return
+				}
+				c.logger.Error().Err(err).Msg("error watching lease file")
+			}
+		}
+	}()
+
+	watcher.Add(c.leaseFile)
+
+	// TODO: update udhcpc pid file
+	// we'll comment this out for now because the pid might change
+	// process := c.GetProcess()
+	// if process == nil {
+	// 	c.logger.Error().Msg("udhcpc process not found")
+	// }
+
+	// block the goroutine until the lease file is updated
+	<-make(chan struct{})
+
+	return nil
+}
+
+func (c *DHCPClient) loadLeaseFile() error {
+	file, err := os.ReadFile(c.leaseFile)
+	if err != nil {
+		return err
+	}
+
+	data := string(file)
+	if data == "" {
+		c.logger.Debug().Msg("udhcpc lease file is empty")
+		return nil
+	}
+
+	lease := &Lease{}
+	err = UnmarshalDHCPCLease(lease, string(file))
+	if err != nil {
+		return err
+	}
+
+	isFirstLoad := c.lease == nil
+	c.lease = lease
+
+	if lease.IPAddress == nil {
+		c.logger.Info().
+			Interface("lease", lease).
+			Str("data", string(file)).
+			Msg("udhcpc lease cleared")
+		return nil
+	}
+
+	msg := "udhcpc lease updated"
+	if isFirstLoad {
+		msg = "udhcpc lease loaded"
+	}
+
+	c.onLeaseChange(lease)
+
+	c.logger.Info().
+		Str("ip", lease.IPAddress.String()).
+		Str("leaseTime", lease.LeaseTime.String()).
+		Interface("data", lease).
+		Msg(msg)
+
+	return nil
+}

log.go

@@ -218,12 +218,13 @@ func ErrorfL(l *zerolog.Logger, format string, err error, args ...interface{}) e
 
 var (
 	logger          = rootLogger.getLogger("jetkvm")
+	networkLogger   = rootLogger.getLogger("network")
 	cloudLogger     = rootLogger.getLogger("cloud")
 	websocketLogger = rootLogger.getLogger("websocket")
 	webrtcLogger    = rootLogger.getLogger("webrtc")
 	nativeLogger    = rootLogger.getLogger("native")
 	nbdLogger       = rootLogger.getLogger("nbd")
-	ntpLogger       = rootLogger.getLogger("ntp")
+	timesyncLogger  = rootLogger.getLogger("timesync")
 	jsonRpcLogger   = rootLogger.getLogger("jsonrpc")
 	watchdogLogger  = rootLogger.getLogger("watchdog")
 	websecureLogger = rootLogger.getLogger("websecure")

main.go

@@ -15,26 +15,38 @@ var appCtx context.Context
 
 func Main() {
 	LoadConfig()
-	logger.Debug().Msg("config loaded")
 
 	var cancel context.CancelFunc
 	appCtx, cancel = context.WithCancel(context.Background())
 	defer cancel()
-	logger.Info().Msg("starting JetKvm")
+
+	systemVersionLocal, appVersionLocal, err := GetLocalVersion()
+	if err != nil {
+		logger.Warn().Err(err).Msg("failed to get local version")
+	}
+
+	logger.Info().
+		Interface("system_version", systemVersionLocal).
+		Interface("app_version", appVersionLocal).
+		Msg("starting JetKVM")
 
 	go runWatchdog()
 	go confirmCurrentSystem()
 
 	http.DefaultClient.Timeout = 1 * time.Minute
 
-	err := rootcerts.UpdateDefaultTransport()
+	err = rootcerts.UpdateDefaultTransport()
 	if err != nil {
-		logger.Warn().Err(err).Msg("failed to load CA certs")
+		logger.Warn().Err(err).Msg("failed to load Root CA certificates")
 	}
+	logger.Info().
+		Int("ca_certs_loaded", len(rootcerts.Certs())).
+		Msg("loaded Root CA certificates")
 
 	initNetwork()
+	initTimeSync()
 
-	go TimeSyncLoop()
+	timeSync.Start()
 
 	StartNativeCtrlSocketServer()
 	StartNativeVideoSocketServer()

mdns.go

@@ -0,0 +1,60 @@
+package kvm
+
+import (
+	"net"
+
+	"github.com/pion/mdns/v2"
+	"golang.org/x/net/ipv4"
+	"golang.org/x/net/ipv6"
+)
+
+var mDNSConn *mdns.Conn
+
+func startMDNS() error {
+	// If server was previously running, stop it
+	if mDNSConn != nil {
+		logger.Info().Msg("stopping mDNS server")
+		err := mDNSConn.Close()
+		if err != nil {
+			logger.Warn().Err(err).Msg("failed to stop mDNS server")
+		}
+	}
+
+	// Start a new server
+	hostname := "jetkvm.local"
+
+	scopedLogger := logger.With().Str("hostname", hostname).Logger()
+	scopedLogger.Info().Msg("starting mDNS server")
+
+	addr4, err := net.ResolveUDPAddr("udp4", mdns.DefaultAddressIPv4)
+	if err != nil {
+		return err
+	}
+
+	addr6, err := net.ResolveUDPAddr("udp6", mdns.DefaultAddressIPv6)
+	if err != nil {
+		return err
+	}
+
+	l4, err := net.ListenUDP("udp4", addr4)
+	if err != nil {
+		return err
+	}
+
+	l6, err := net.ListenUDP("udp6", addr6)
+	if err != nil {
+		return err
+	}
+
+	mDNSConn, err = mdns.Server(ipv4.NewPacketConn(l4), ipv6.NewPacketConn(l6), &mdns.Config{
+		LocalNames:    []string{hostname}, //TODO: make it configurable
+		LoggerFactory: defaultLoggerFactory,
+	})
+	if err != nil {
+		scopedLogger.Warn().Err(err).Msg("failed to start mDNS server")
+		mDNSConn = nil
+		return err
+	}
+	//defer server.Close()
+	return nil
+}

network.go

@@ -1,214 +1,308 @@
 package kvm
 
 import (
-	"bytes"
 	"fmt"
 	"net"
 	"os"
-	"strings"
+	"sync"
 	"time"
 
-	"os/exec"
+	"github.com/Masterminds/semver/v3"
-
+	"github.com/jetkvm/kvm/internal/udhcpc"
-	"github.com/hashicorp/go-envparse"
+	"github.com/rs/zerolog"
-	"github.com/pion/mdns/v2"
-	"golang.org/x/net/ipv4"
-	"golang.org/x/net/ipv6"
 
 	"github.com/vishvananda/netlink"
 	"github.com/vishvananda/netlink/nl"
 )
 
-var mDNSConn *mdns.Conn
+var (
+	networkState *NetworkInterfaceState
+)
 
-var networkState NetworkState
+type DhcpTargetState int
 
-type NetworkState struct {
+const (
-	Up   bool
+	DhcpTargetStateDoNothing DhcpTargetState = iota
-	IPv4 string
+	DhcpTargetStateStart
-	IPv6 string
+	DhcpTargetStateStop
-	MAC  string
+	DhcpTargetStateRenew
+	DhcpTargetStateRelease
+)
+
+type NetworkInterfaceState struct {
+	interfaceName string
+	interfaceUp   bool
+	ipv4Addr      *net.IP
+	ipv6Addr      *net.IP
+	macAddr       *net.HardwareAddr
+
+	l         *zerolog.Logger
+	stateLock sync.Mutex
+
+	dhcpClient *udhcpc.DHCPClient
+
+	onStateChange  func(state *NetworkInterfaceState)
+	onInitialCheck func(state *NetworkInterfaceState)
 
 	checked bool
 }
 
-func (s *NetworkState) IsUp() bool {
+func (s *NetworkInterfaceState) IsUp() bool {
-	return s.Up && s.IPv4 != "" && s.IPv6 != ""
+	return s.interfaceUp
 }
 
-func (s *NetworkState) HasIPAssigned() bool {
+func (s *NetworkInterfaceState) HasIPAssigned() bool {
-	return s.IPv4 != "" || s.IPv6 != ""
+	return s.ipv4Addr != nil || s.ipv6Addr != nil
 }
 
-func (s *NetworkState) IsOnline() bool {
+func (s *NetworkInterfaceState) IsOnline() bool {
-	return s.Up && s.HasIPAssigned()
+	return s.IsUp() && s.HasIPAssigned()
 }
 
-type LocalIpInfo struct {
+func (s *NetworkInterfaceState) IPv4() *net.IP {
-	IPv4 string
+	return s.ipv4Addr
-	IPv6 string
+}
-	MAC  string
+
+func (s *NetworkInterfaceState) IPv4String() string {
+	if s.ipv4Addr == nil {
+		return "..."
+	}
+	return s.ipv4Addr.String()
+}
+
+func (s *NetworkInterfaceState) IPv6() *net.IP {
+	return s.ipv6Addr
+}
+
+func (s *NetworkInterfaceState) IPv6String() string {
+	if s.ipv6Addr == nil {
+		return "..."
+	}
+	return s.ipv6Addr.String()
+}
+
+func (s *NetworkInterfaceState) MAC() *net.HardwareAddr {
+	return s.macAddr
+}
+
+func (s *NetworkInterfaceState) MACString() string {
+	if s.macAddr == nil {
+		return ""
+	}
+	return s.macAddr.String()
 }
 
 const (
-	NetIfName     = "eth0"
+	// TODO: add support for multiple interfaces
-	DHCPLeaseFile = "/run/udhcpc.%s.info"
+	NetIfName = "eth0"
 )
 
-// setDhcpClientState sends signals to udhcpc to change it's current mode
+func NewNetworkInterfaceState(ifname string) *NetworkInterfaceState {
-// of operation. Setting active to true will force udhcpc to renew the DHCP lease.
+	logger := networkLogger.With().Str("interface", ifname).Logger()
-// Setting active to false will put udhcpc into idle mode.
+
-func setDhcpClientState(active bool) {
+	s := &NetworkInterfaceState{
-	var signal string
+		interfaceName: ifname,
-	if active {
+		stateLock:     sync.Mutex{},
-		signal = "-SIGUSR1"
+		l:             &logger,
-	} else {
+		onStateChange: func(state *NetworkInterfaceState) {
-		signal = "-SIGUSR2"
+			go func() {
+				waitCtrlClientConnected()
+				requestDisplayUpdate()
+			}()
+		},
+		onInitialCheck: func(state *NetworkInterfaceState) {
+			go func() {
+				waitCtrlClientConnected()
+				requestDisplayUpdate()
+			}()
+		},
 	}
 
-	cmd := exec.Command("/usr/bin/killall", signal, "udhcpc")
+	// use a pid file for udhcpc if the system version is 0.2.4 or higher
-	if err := cmd.Run(); err != nil {
+	dhcpPidFile := ""
-		logger.Warn().Err(err).Msg("network: setDhcpClientState: failed to change udhcpc state")
+	systemVersionLocal, _, _ := GetLocalVersion()
+	if systemVersionLocal != nil &&
+		systemVersionLocal.Compare(semver.MustParse("0.2.4")) >= 0 {
+		dhcpPidFile = fmt.Sprintf("/run/udhcpc.%s.pid", ifname)
 	}
+
+	// create the dhcp client
+	dhcpClient := udhcpc.NewDHCPClient(&udhcpc.DHCPClientOptions{
+		InterfaceName: ifname,
+		PidFile:       dhcpPidFile,
+		Logger:        &logger,
+		OnLeaseChange: func(lease *udhcpc.Lease) {
+			s.update()
+		},
+	})
+
+	s.dhcpClient = dhcpClient
+
+	return s
 }
 
-func checkNetworkState() {
+func (s *NetworkInterfaceState) update() (DhcpTargetState, error) {
-	iface, err := netlink.LinkByName(NetIfName)
+	s.stateLock.Lock()
+	defer s.stateLock.Unlock()
+
+	dhcpTargetState := DhcpTargetStateDoNothing
+
+	iface, err := netlink.LinkByName(s.interfaceName)
 	if err != nil {
-		logger.Warn().Err(err).Str("interface", NetIfName).Msg("failed to get interface")
+		s.l.Error().Err(err).Msg("failed to get interface")
-		return
+		return dhcpTargetState, err
 	}
 
-	newState := NetworkState{
+	// detect if the interface status changed
-		Up:  iface.Attrs().OperState == netlink.OperUp,
+	var changed bool
-		MAC: iface.Attrs().HardwareAddr.String(),
+	attrs := iface.Attrs()
+	state := attrs.OperState
+	newInterfaceUp := state == netlink.OperUp
 
-		checked: true,
+	// check if the interface is coming up
+	interfaceGoingUp := s.interfaceUp == false && newInterfaceUp == true
+	interfaceGoingDown := s.interfaceUp == true && newInterfaceUp == false
+
+	if s.interfaceUp != newInterfaceUp {
+		s.interfaceUp = newInterfaceUp
+		changed = true
 	}
 
+	if changed {
+		if interfaceGoingUp {
+			s.l.Info().Msg("interface state transitioned to up")
+			dhcpTargetState = DhcpTargetStateRenew
+		} else if interfaceGoingDown {
+			s.l.Info().Msg("interface state transitioned to down")
+		}
+	}
+
+	// set the mac address
+	s.macAddr = &attrs.HardwareAddr
+
+	// get the ip addresses
 	addrs, err := netlink.AddrList(iface, nl.FAMILY_ALL)
 	if err != nil {
-		logger.Warn().Err(err).Str("interface", NetIfName).Msg("failed to get addresses")
+		s.l.Error().Err(err).Msg("failed to get ip addresses")
+		return dhcpTargetState, err
 	}
 
-	// If the link is going down, put udhcpc into idle mode.
+	var (
-	// If the link is coming back up, activate udhcpc and force it to renew the lease.
+		ipv4Addresses = make([]net.IP, 0)
-	if newState.Up != networkState.Up {
+		ipv6Addresses = make([]net.IP, 0)
-		setDhcpClientState(newState.Up)
+	)
-	}
 
 	for _, addr := range addrs {
 		if addr.IP.To4() != nil {
-			if !newState.Up && networkState.Up {
+			scopedLogger := s.l.With().Str("ipv4", addr.IP.String()).Logger()
-				// If the network is going down, remove all IPv4 addresses from the interface.
+			if interfaceGoingDown {
-				logger.Info().Str("address", addr.IP.String()).Msg("network: state transitioned to down, removing IPv4 address")
+				// remove all IPv4 addresses from the interface.
+				scopedLogger.Info().Msg("state transitioned to down, removing IPv4 address")
 				err := netlink.AddrDel(iface, &addr)
 				if err != nil {
-					logger.Warn().Err(err).Str("address", addr.IP.String()).Msg("network: failed to delete address")
+					scopedLogger.Warn().Err(err).Msg("failed to delete address")
 				}
-
+				// notify the DHCP client to release the lease
-				newState.IPv4 = "..."
+				dhcpTargetState = DhcpTargetStateRelease
-			} else {
+				continue
-				newState.IPv4 = addr.IP.String()
 			}
-		} else if addr.IP.To16() != nil && newState.IPv6 == "" {
+			ipv4Addresses = append(ipv4Addresses, addr.IP)
-			newState.IPv6 = addr.IP.String()
+		} else if addr.IP.To16() != nil {
+			scopedLogger := s.l.With().Str("ipv6", addr.IP.String()).Logger()
+			// check if it's a link local address
+			if !addr.IP.IsGlobalUnicast() {
+				scopedLogger.Trace().Msg("not a global unicast address, skipping")
+				continue
+			}
+
+			if interfaceGoingDown {
+				scopedLogger.Info().Msg("state transitioned to down, removing IPv6 address")
+				err := netlink.AddrDel(iface, &addr)
+				if err != nil {
+					scopedLogger.Warn().Err(err).Msg("failed to delete address")
+				}
+				continue
+			}
+			ipv6Addresses = append(ipv6Addresses, addr.IP)
 		}
 	}
 
-	if newState != networkState {
+	if len(ipv4Addresses) > 0 {
-		logger.Info().
+		// compare the addresses to see if there's a change
-			Interface("newState", newState).
+		if s.ipv4Addr == nil || s.ipv4Addr.String() != ipv4Addresses[0].String() {
-			Interface("oldState", networkState).
+			scopedLogger := s.l.With().Str("ipv4", ipv4Addresses[0].String()).Logger()
-			Msg("network state changed")
+			if s.ipv4Addr != nil {
-
+				scopedLogger.Info().
-		// restart MDNS
+					Str("old_ipv4", s.ipv4Addr.String()).
-		_ = startMDNS()
+					Msg("IPv4 address changed")
-		networkState = newState
+				changed = true
-		requestDisplayUpdate()
+			} else {
+				scopedLogger.Info().Msg("IPv4 address found")
+			}
+			s.ipv4Addr = &ipv4Addresses[0]
+			changed = true
+		}
 	}
+
+	if len(ipv6Addresses) > 0 {
+		// compare the addresses to see if there's a change
+		if s.ipv6Addr == nil || s.ipv6Addr.String() != ipv6Addresses[0].String() {
+			scopedLogger := s.l.With().Str("ipv6", ipv6Addresses[0].String()).Logger()
+			if s.ipv6Addr != nil {
+				scopedLogger.Info().
+					Str("old_ipv6", s.ipv6Addr.String()).
+					Msg("IPv6 address changed")
+			} else {
+				scopedLogger.Info().Msg("IPv6 address found")
+			}
+			s.ipv6Addr = &ipv6Addresses[0]
+			changed = true
+		}
+	}
+
+	// if it's the initial check, we'll set changed to false
+	initialCheck := !s.checked
+	if initialCheck {
+		s.checked = true
+		changed = false
+	}
+
+	if initialCheck {
+		s.onInitialCheck(s)
+	} else if changed {
+		s.onStateChange(s)
+	}
+
+	return dhcpTargetState, nil
 }
 
-func startMDNS() error {
+func (s *NetworkInterfaceState) CheckAndUpdateDhcp() error {
-	// If server was previously running, stop it
+	dhcpTargetState, err := s.update()
-	if mDNSConn != nil {
-		logger.Info().Msg("stopping mDNS server")
-		err := mDNSConn.Close()
-		if err != nil {
-			logger.Warn().Err(err).Msg("failed to stop mDNS server")
-		}
-	}
-
-	// Start a new server
-	hostname := "jetkvm.local"
-
-	scopedLogger := logger.With().Str("hostname", hostname).Logger()
-	scopedLogger.Info().Msg("starting mDNS server")
-
-	addr4, err := net.ResolveUDPAddr("udp4", mdns.DefaultAddressIPv4)
 	if err != nil {
-		return err
+		return ErrorfL(s.l, "failed to update network state", err)
 	}
 
-	addr6, err := net.ResolveUDPAddr("udp6", mdns.DefaultAddressIPv6)
+	switch dhcpTargetState {
-	if err != nil {
+	case DhcpTargetStateRenew:
-		return err
+		s.l.Info().Msg("renewing DHCP lease")
+		s.dhcpClient.Renew()
+	case DhcpTargetStateRelease:
+		s.l.Info().Msg("releasing DHCP lease")
+		s.dhcpClient.Release()
+	case DhcpTargetStateStart:
+		s.l.Warn().Msg("dhcpTargetStateStart not implemented")
+	case DhcpTargetStateStop:
+		s.l.Warn().Msg("dhcpTargetStateStop not implemented")
 	}
 
-	l4, err := net.ListenUDP("udp4", addr4)
-	if err != nil {
-		return err
-	}
-
-	l6, err := net.ListenUDP("udp6", addr6)
-	if err != nil {
-		return err
-	}
-
-	mDNSConn, err = mdns.Server(ipv4.NewPacketConn(l4), ipv6.NewPacketConn(l6), &mdns.Config{
-		LocalNames:    []string{hostname}, //TODO: make it configurable
-		LoggerFactory: defaultLoggerFactory,
-	})
-	if err != nil {
-		scopedLogger.Warn().Err(err).Msg("failed to start mDNS server")
-		mDNSConn = nil
-		return err
-	}
-	//defer server.Close()
 	return nil
 }
 
-func getNTPServersFromDHCPInfo() ([]string, error) {
+func (s *NetworkInterfaceState) HandleLinkUpdate(update netlink.LinkUpdate) {
-	buf, err := os.ReadFile(fmt.Sprintf(DHCPLeaseFile, NetIfName))
+	if update.Link.Attrs().Name == s.interfaceName {
-	if err != nil {
+		s.l.Info().Interface("update", update).Msg("interface link update received")
-		// do not return error if file does not exist
+		s.CheckAndUpdateDhcp()
-		if os.IsNotExist(err) {
-			return nil, nil
-		}
-		return nil, fmt.Errorf("failed to load udhcpc info: %w", err)
 	}
-
-	// parse udhcpc info
-	env, err := envparse.Parse(bytes.NewReader(buf))
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse udhcpc info: %w", err)
-	}
-
-	val, ok := env["ntpsrv"]
-	if !ok {
-		return nil, nil
-	}
-
-	var servers []string
-
-	for _, server := range strings.Fields(val) {
-		if net.ParseIP(server) == nil {
-			logger.Info().Str("server", server).Msg("invalid NTP server IP, ignoring")
-		}
-		servers = append(servers, server)
-	}
-
-	return servers, nil
 }
 
 func initNetwork() {
@@ -218,25 +312,29 @@ func initNetwork() {
 	done := make(chan struct{})
 
 	if err := netlink.LinkSubscribe(updates, done); err != nil {
-		logger.Warn().Err(err).Msg("failed to subscribe to link updates")
+		networkLogger.Warn().Err(err).Msg("failed to subscribe to link updates")
 		return
 	}
 
+	// TODO: support multiple interfaces
+	networkState = NewNetworkInterfaceState(NetIfName)
+	go networkState.dhcpClient.Run()
+
+	if err := networkState.CheckAndUpdateDhcp(); err != nil {
+		os.Exit(1)
+	}
+
 	go func() {
 		waitCtrlClientConnected()
-		checkNetworkState()
 		ticker := time.NewTicker(1 * time.Second)
 		defer ticker.Stop()
 
 		for {
 			select {
 			case update := <-updates:
-				if update.Link.Attrs().Name == NetIfName {
+				networkState.HandleLinkUpdate(update)
-					logger.Info().Interface("update", update).Msg("link update")
-					checkNetworkState()
-				}
 			case <-ticker.C:
-				checkNetworkState()
+				_ = networkState.CheckAndUpdateDhcp()
 			case <-done:
 				return
 			}

ntp.go

@@ -1,214 +0,0 @@
-package kvm
-
-import (
-	"fmt"
-	"net/http"
-	"os/exec"
-	"strconv"
-	"time"
-
-	"github.com/beevik/ntp"
-)
-
-const (
-	timeSyncRetryStep     = 5 * time.Second
-	timeSyncRetryMaxInt   = 1 * time.Minute
-	timeSyncWaitNetChkInt = 100 * time.Millisecond
-	timeSyncWaitNetUpInt  = 3 * time.Second
-	timeSyncInterval      = 1 * time.Hour
-	timeSyncTimeout       = 2 * time.Second
-)
-
-var (
-	builtTimestamp        string
-	timeSyncRetryInterval = 0 * time.Second
-	timeSyncSuccess       = false
-	defaultNTPServers     = []string{
-		"time.cloudflare.com",
-		"time.apple.com",
-	}
-)
-
-func isTimeSyncNeeded() bool {
-	if builtTimestamp == "" {
-		ntpLogger.Warn().Msg("built timestamp is not set, time sync is needed")
-		return true
-	}
-
-	ts, err := strconv.Atoi(builtTimestamp)
-	if err != nil {
-		ntpLogger.Warn().Str("error", err.Error()).Msg("failed to parse built timestamp")
-		return true
-	}
-
-	// builtTimestamp is UNIX timestamp in seconds
-	builtTime := time.Unix(int64(ts), 0)
-	now := time.Now()
-
-	if now.Sub(builtTime) < 0 {
-		ntpLogger.Warn().
-			Str("built_time", builtTime.Format(time.RFC3339)).
-			Str("now", now.Format(time.RFC3339)).
-			Msg("system time is behind the built time, time sync is needed")
-		return true
-	}
-
-	return false
-}
-
-func TimeSyncLoop() {
-	for {
-		if !networkState.checked {
-			time.Sleep(timeSyncWaitNetChkInt)
-			continue
-		}
-
-		if !networkState.IsOnline() {
-			ntpLogger.Info().Msg("waiting for network to be online")
-			time.Sleep(timeSyncWaitNetUpInt)
-			continue
-		}
-
-		// check if time sync is needed, but do nothing for now
-		isTimeSyncNeeded()
-
-		ntpLogger.Info().Msg("syncing system time")
-		start := time.Now()
-		err := SyncSystemTime()
-		if err != nil {
-			ntpLogger.Error().Str("error", err.Error()).Msg("failed to sync system time")
-
-			// retry after a delay
-			timeSyncRetryInterval += timeSyncRetryStep
-			time.Sleep(timeSyncRetryInterval)
-			// reset the retry interval if it exceeds the max interval
-			if timeSyncRetryInterval > timeSyncRetryMaxInt {
-				timeSyncRetryInterval = 0
-			}
-
-			continue
-		}
-		timeSyncSuccess = true
-		ntpLogger.Info().Str("now", time.Now().Format(time.RFC3339)).
-			Str("time_taken", time.Since(start).String()).
-			Msg("time sync successful")
-		time.Sleep(timeSyncInterval) // after the first sync is done
-	}
-}
-
-func SyncSystemTime() (err error) {
-	now, err := queryNetworkTime()
-	if err != nil {
-		return fmt.Errorf("failed to query network time: %w", err)
-	}
-	err = setSystemTime(*now)
-	if err != nil {
-		return fmt.Errorf("failed to set system time: %w", err)
-	}
-	return nil
-}
-
-func queryNetworkTime() (*time.Time, error) {
-	ntpServers, err := getNTPServersFromDHCPInfo()
-	if err != nil {
-		ntpLogger.Info().Err(err).Msg("failed to get NTP servers from DHCP info")
-	}
-
-	if ntpServers == nil {
-		ntpServers = defaultNTPServers
-		ntpLogger.Info().
-			Interface("ntp_servers", ntpServers).
-			Msg("using default NTP servers")
-	} else {
-		ntpLogger.Info().
-			Interface("ntp_servers", ntpServers).
-			Msg("using NTP servers from DHCP")
-	}
-
-	for _, server := range ntpServers {
-		now, err, response := queryNtpServer(server, timeSyncTimeout)
-
-		scopedLogger := ntpLogger.With().
-			Str("server", server).
-			Logger()
-
-		if err == nil {
-			scopedLogger.Info().
-				Str("time", now.Format(time.RFC3339)).
-				Str("reference", response.ReferenceString()).
-				Str("rtt", response.RTT.String()).
-				Str("clockOffset", response.ClockOffset.String()).
-				Uint8("stratum", response.Stratum).
-				Msg("NTP server returned time")
-			return now, nil
-		} else {
-			scopedLogger.Error().
-				Str("error", err.Error()).
-				Msg("failed to query NTP server")
-		}
-	}
-
-	httpUrls := []string{
-		"http://apple.com",
-		"http://cloudflare.com",
-	}
-	for _, url := range httpUrls {
-		now, err, response := queryHttpTime(url, timeSyncTimeout)
-
-		var status string
-		if response != nil {
-			status = response.Status
-		}
-
-		scopedLogger := ntpLogger.With().
-			Str("http_url", url).
-			Str("status", status).
-			Logger()
-
-		if err == nil {
-			scopedLogger.Info().
-				Str("time", now.Format(time.RFC3339)).
-				Msg("HTTP server returned time")
-			return now, nil
-		} else {
-			scopedLogger.Error().
-				Str("error", err.Error()).
-				Msg("failed to query HTTP server")
-		}
-	}
-
-	return nil, ErrorfL(ntpLogger, "failed to query network time, all NTP servers and HTTP servers failed", nil)
-}
-
-func queryNtpServer(server string, timeout time.Duration) (now *time.Time, err error, response *ntp.Response) {
-	resp, err := ntp.QueryWithOptions(server, ntp.QueryOptions{Timeout: timeout})
-	if err != nil {
-		return nil, err, nil
-	}
-	return &resp.Time, nil, resp
-}
-
-func queryHttpTime(url string, timeout time.Duration) (now *time.Time, err error, response *http.Response) {
-	client := http.Client{
-		Timeout: timeout,
-	}
-	resp, err := client.Head(url)
-	if err != nil {
-		return nil, err, nil
-	}
-	dateStr := resp.Header.Get("Date")
-	parsedTime, err := time.Parse(time.RFC1123, dateStr)
-	if err != nil {
-		return nil, err, resp
-	}
-	return &parsedTime, nil, resp
-}
-
-func setSystemTime(now time.Time) error {
-	nowStr := now.Format("2006-01-02 15:04:05")
-	output, err := exec.Command("date", "-s", nowStr).CombinedOutput()
-	if err != nil {
-		return fmt.Errorf("failed to run date -s: %w, %s", err, string(output))
-	}
-	return nil
-}

timesync.go

@@ -0,0 +1,69 @@
+package kvm
+
+import (
+	"strconv"
+	"time"
+
+	"github.com/jetkvm/kvm/internal/timesync"
+)
+
+const (
+	timeSyncRetryStep     = 5 * time.Second
+	timeSyncRetryMaxInt   = 1 * time.Minute
+	timeSyncWaitNetChkInt = 100 * time.Millisecond
+	timeSyncWaitNetUpInt  = 3 * time.Second
+)
+
+var (
+	timeSync          *timesync.TimeSync
+	defaultNTPServers = []string{
+		"time.cloudflare.com",
+		"time.apple.com",
+	}
+	defaultHTTPUrls = []string{
+		"http://apple.com",
+		"http://cloudflare.com",
+	}
+	builtTimestamp string
+)
+
+func isTimeSyncNeeded() bool {
+	if builtTimestamp == "" {
+		timesyncLogger.Warn().Msg("built timestamp is not set, time sync is needed")
+		return true
+	}
+
+	ts, err := strconv.Atoi(builtTimestamp)
+	if err != nil {
+		timesyncLogger.Warn().Str("error", err.Error()).Msg("failed to parse built timestamp")
+		return true
+	}
+
+	// builtTimestamp is UNIX timestamp in seconds
+	builtTime := time.Unix(int64(ts), 0)
+	now := time.Now()
+
+	if now.Sub(builtTime) < 0 {
+		timesyncLogger.Warn().
+			Str("built_time", builtTime.Format(time.RFC3339)).
+			Str("now", now.Format(time.RFC3339)).
+			Msg("system time is behind the built time, time sync is needed")
+		return true
+	}
+
+	return false
+}
+
+func initTimeSync() {
+	timeSync = timesync.NewTimeSync(
+		func() (bool, error) {
+			if !networkState.IsOnline() {
+				return false, nil
+			}
+			return true, nil
+		},
+		defaultNTPServers,
+		defaultHTTPUrls,
+		timesyncLogger,
+	)
+}

web_tls.go

@@ -53,7 +53,7 @@ func initCertStore() {
 
 func getCertificate(info *tls.ClientHelloInfo) (*tls.Certificate, error) {
 	if config.TLSMode == "self-signed" {
-		if isTimeSyncNeeded() || !timeSyncSuccess {
+		if isTimeSyncNeeded() || !timeSync.IsSyncSuccess() {
 			return nil, fmt.Errorf("time is not synced")
 		}
 		return certSigner.GetCertificate(info)