AdGuard Home as a system service

1. Reworked working with command-line arguments
2. Added service control actions: install/uninstall/start/stop/status
3. Added log settings to the configuration file
4. Updated the README file

.gitignore

@@ -4,6 +4,7 @@
 /AdGuardHome
 /AdGuardHome.exe
 /AdGuardHome.yaml
+/AdGuardHome.log
 /data/
 /build/
 /dist/

README.md

@@ -99,6 +99,35 @@ sudo ./AdGuardHome
 
 Now open the browser and navigate to http://localhost:3000/ to control your AdGuard Home service.
 
+### Command-line arguments
+
+Here is a list of all available command-line arguments.
+
+```
+$ ./AdGuardHome -h
+Usage:
+
+./AdGuardHome [options]
+
+Options:
+  -c, --config                       path to config file
+  -o, --host                         host address to bind HTTP server on
+  -p, --port                         port to serve HTTP pages on
+  -v, --verbose                      enable verbose output
+  -s, --service                      service control action: status, install, uninstall, start, stop, restart
+  -l, --logfile                      path to the log file. If empty, writes to stdout, if 'syslog' -- system log
+  -h, --help                         print this help
+```
+
+Please note, that you can register AdGuard Home as a system service on Windows, Linux/(systemd | Upstart | SysV), and OSX/Launchd.
+
+* `AdGuardHome -s install` - install as a system service.
+* `AdGuardHome -s uninstall` - uninstall's AdGuard Home service.
+* `AdGuardHome -s start` - starts the service.
+* `AdGuardHome -s stop` - stops the service.
+* `AdGuardHome -s restart` - restarts the service.
+* `AdGuardHome -s status` - shows the current service status.
+
 ### Running without superuser
 
 You can run AdGuard Home without superuser privileges, but you need to either grant the binary a capability (on Linux) or instruct it to use a different port (all platforms).
@@ -139,6 +168,7 @@ Settings are stored in [YAML format](https://en.wikipedia.org/wiki/YAML), possib
  * `auth_name` — Web interface optional authorization username.
  * `auth_pass` — Web interface optional authorization password.
  * `dns` — DNS configuration section.
+   * `bind_host` - DNS interface IP address to listen on. 
    * `port` — DNS server port to listen on.
    * `protection_enabled` — Whether any kind of filtering and protection should be done, when off it works as a plain dns forwarder.
    * `filtering_enabled` — Filtering of DNS requests based on filter lists.
@@ -159,7 +189,17 @@ Settings are stored in [YAML format](https://en.wikipedia.org/wiki/YAML), possib
    * `name` — Name of the filter. If it's an adguard syntax filter it will get updated automatically, otherwise it stays unchanged.
    * `last_updated` — Time when the filter was last updated from server.
    * `ID` - filter ID (must be unique).
+ * `dhcp` - Built-in DHCP server configuration.
+   * `enabled` - DHCP server status.
+   * `interface_name` - network interface name (eth0, en0 and so on).
+   * `gateway_ip` - gateway IP address.
+   * `subnet_mask` - subnet mask.
+   * `range_start` - start IP address of the controlled range.  
+   * `range_end` - end IP address of the controlled range.
+   * `lease_duration` - lease duration in seconds. If 0, using default duration (2 hours).
  * `user_rules` — User-specified filtering rules.
+ * `log_file` — Path to the log file. If empty, writes to stdout, if 'syslog' -- system log.
+ * `verbose` — Enable our disables debug verbose output.
 
 Removing an entry from settings file will reset it to the default value. Deleting the file will reset all settings to the default values.
 

app.go

@@ -3,6 +3,8 @@ package main
 import (
 	"bufio"
 	"fmt"
+	stdlog "log"
+	"log/syslog"
 	"net"
 	"net/http"
 	"os"
@@ -20,58 +22,19 @@ import (
 // VersionString will be set through ldflags, contains current version
 var VersionString = "undefined"
 
+// main is the entry point
 func main() {
-	log.Printf("AdGuard Home web interface backend, version %s\n", VersionString)
-	box := packr.NewBox("build/static")
-	{
-		executable, err := os.Executable()
-		if err != nil {
-			panic(err)
-		}
-
-		executableName := filepath.Base(executable)
-		if executableName == "AdGuardHome" {
-			// Binary build
-			config.ourBinaryDir = filepath.Dir(executable)
-		} else {
-			// Most likely we're debugging -- using current working directory in this case
-			workDir, _ := os.Getwd()
-			config.ourBinaryDir = workDir
-		}
-		log.Printf("Current working directory is %s", config.ourBinaryDir)
-	}
-
 	// config can be specified, which reads options from there, but other command line flags have to override config values
 	// therefore, we must do it manually instead of using a lib
-	loadOptions()
+	args := loadOptions()
 
-	// Load filters from the disk
-	// And if any filter has zero ID, assign a new one
-	for i := range config.Filters {
-		filter := &config.Filters[i] // otherwise we're operating on a copy
-		if filter.ID == 0 {
-			filter.ID = assignUniqueFilterID()
-		}
-		err := filter.load()
-		if err != nil {
-			// This is okay for the first start, the filter will be loaded later
-			log.Printf("Couldn't load filter %d contents due to %s", filter.ID, err)
-			// clear LastUpdated so it gets fetched right away
-		}
-		if len(filter.Rules) == 0 {
-			filter.LastUpdated = time.Time{}
-		}
+	if args.serviceControlAction != "" {
+		handleServiceControlAction(args.serviceControlAction)
+		return
 	}
 
-	// Update filters we've just loaded right away, don't wait for periodic update timer
-	go func() {
-		refreshFiltersIfNecessary(false)
-		// Save the updated config
-		err := config.write()
-		if err != nil {
-			log.Fatal(err)
-		}
-	}()
+	// run the protection
+	run(args)
 
 	signalChannel := make(chan os.Signal)
 	signal.Notify(signalChannel, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP, syscall.SIGQUIT)
@@ -81,110 +44,23 @@ func main() {
 		os.Exit(0)
 	}()
 
-	// Save the updated config
-	err := config.write()
-	if err != nil {
-		log.Fatal(err)
-	}
-
 	address := net.JoinHostPort(config.BindHost, strconv.Itoa(config.BindPort))
-
-	go periodicallyRefreshFilters()
-
-	http.Handle("/", optionalAuthHandler(http.FileServer(box)))
-	registerControlHandlers()
-
-	err = startDNSServer()
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	err = startDHCPServer()
-	if err != nil {
-		log.Fatal(err)
-	}
-
 	URL := fmt.Sprintf("http://%s", address)
 	log.Println("Go to " + URL)
 	log.Fatal(http.ListenAndServe(address, nil))
 }
 
-func cleanup() {
-	err := stopDNSServer()
-	if err != nil {
-		log.Printf("Couldn't stop DNS server: %s", err)
+// run initializes configuration and runs the AdGuard Home
+func run(args options) {
+	if args.configFilename != "" {
+		config.ourConfigFilename = args.configFilename
 	}
-}
 
-func getInput() (string, error) {
-	scanner := bufio.NewScanner(os.Stdin)
-	scanner.Scan()
-	text := scanner.Text()
-	err := scanner.Err()
-	return text, err
-}
+	// configure log level and output
+	configureLogger(args)
 
-// loadOptions reads command line arguments and initializes configuration
-func loadOptions() {
-	var printHelp func()
-	var configFilename *string
-	var bindHost *string
-	var bindPort *int
-	var opts = []struct {
-		longName          string
-		shortName         string
-		description       string
-		callbackWithValue func(value string)
-		callbackNoValue   func()
-	}{
-		{"config", "c", "path to config file", func(value string) { configFilename = &value }, nil},
-		{"host", "h", "host address to bind HTTP server on", func(value string) { bindHost = &value }, nil},
-		{"port", "p", "port to serve HTTP pages on", func(value string) {
-			v, err := strconv.Atoi(value)
-			if err != nil {
-				panic("Got port that is not a number")
-			}
-			bindPort = &v
-		}, nil},
-		{"verbose", "v", "enable verbose output", nil, func() { log.Verbose = true }},
-		{"help", "h", "print this help", nil, func() { printHelp(); os.Exit(64) }},
-	}
-	printHelp = func() {
-		fmt.Printf("Usage:\n\n")
-		fmt.Printf("%s [options]\n\n", os.Args[0])
-		fmt.Printf("Options:\n")
-		for _, opt := range opts {
-			fmt.Printf("  -%s, %-30s %s\n", opt.shortName, "--"+opt.longName, opt.description)
-		}
-	}
-	for i := 1; i < len(os.Args); i++ {
-		v := os.Args[i]
-		knownParam := false
-		for _, opt := range opts {
-			if v == "--"+opt.longName || v == "-"+opt.shortName {
-				if opt.callbackWithValue != nil {
-					if i+1 > len(os.Args) {
-						log.Printf("ERROR: Got %s without argument\n", v)
-						os.Exit(64)
-					}
-					i++
-					opt.callbackWithValue(os.Args[i])
-				} else if opt.callbackNoValue != nil {
-					opt.callbackNoValue()
-				}
-				knownParam = true
-				break
-			}
-		}
-		if !knownParam {
-			log.Printf("ERROR: unknown option %v\n", v)
-			printHelp()
-			os.Exit(64)
-		}
-	}
-	if configFilename != nil {
-		config.ourConfigFilename = *configFilename
-	}
+	// print the first message after logger is configured
+	log.Printf("AdGuard Home, version %s\n", VersionString)
 
 	err := askUsernamePasswordIfPossible()
 	if err != nil {
@@ -204,12 +80,217 @@ func loadOptions() {
 	}
 
 	// override bind host/port from the console
-	if bindHost != nil {
-		config.BindHost = *bindHost
+	if args.bindHost != "" {
+		config.BindHost = args.bindHost
 	}
-	if bindPort != nil {
-		config.BindPort = *bindPort
+	if args.bindPort != 0 {
+		config.BindPort = args.bindPort
 	}
+
+	// Load filters from the disk
+	// And if any filter has zero ID, assign a new one
+	for i := range config.Filters {
+		filter := &config.Filters[i] // otherwise we're operating on a copy
+		if filter.ID == 0 {
+			filter.ID = assignUniqueFilterID()
+		}
+		err = filter.load()
+		if err != nil {
+			// This is okay for the first start, the filter will be loaded later
+			log.Printf("Couldn't load filter %d contents due to %s", filter.ID, err)
+			// clear LastUpdated so it gets fetched right away
+		}
+		if len(filter.Rules) == 0 {
+			filter.LastUpdated = time.Time{}
+		}
+	}
+
+	// Save the updated config
+	err = config.write()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	box := packr.NewBox("build/static")
+	{
+		executable, osErr := os.Executable()
+		if osErr != nil {
+			panic(osErr)
+		}
+
+		executableName := filepath.Base(executable)
+		if executableName == "AdGuardHome" {
+			// Binary build
+			config.ourBinaryDir = filepath.Dir(executable)
+		} else {
+			// Most likely we're debugging -- using current working directory in this case
+			workDir, _ := os.Getwd()
+			config.ourBinaryDir = workDir
+		}
+		log.Printf("Current working directory is %s", config.ourBinaryDir)
+	}
+	http.Handle("/", optionalAuthHandler(http.FileServer(box)))
+	registerControlHandlers()
+
+	err = startDNSServer()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = startDHCPServer()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Update filters we've just loaded right away, don't wait for periodic update timer
+	go func() {
+		refreshFiltersIfNecessary(false)
+		// Save the updated config
+		err := config.write()
+		if err != nil {
+			log.Fatal(err)
+		}
+	}()
+	// Schedule automatic filters updates
+	go periodicallyRefreshFilters()
+}
+
+// configureLogger configures logger level and output
+func configureLogger(args options) {
+	ls := getLogSettings()
+
+	// command-line arguments can override config settings
+	if args.verbose {
+		ls.Verbose = true
+	}
+	if args.logFile != "" {
+		ls.LogFile = args.logFile
+	}
+
+	log.Verbose = ls.Verbose
+
+	if ls.LogFile == "" {
+		return
+	}
+
+	// TODO: add windows eventlog support
+	if ls.LogFile == "syslog" {
+		w, err := syslog.New(syslog.LOG_INFO, "AdGuard Home")
+		if err != nil {
+			log.Fatalf("cannot initialize syslog: %s", err)
+		}
+		stdlog.SetOutput(w)
+	}
+
+	logFilePath := filepath.Join(config.ourBinaryDir, ls.LogFile)
+	file, err := os.OpenFile(logFilePath, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0755)
+	if err != nil {
+		log.Fatalf("cannot create a log file: %s", err)
+	}
+	stdlog.SetOutput(file)
+}
+
+func cleanup() {
+	log.Printf("Stopping AdGuard Home")
+
+	err := stopDNSServer()
+	if err != nil {
+		log.Printf("Couldn't stop DNS server: %s", err)
+	}
+	err = stopDHCPServer()
+	if err != nil {
+		log.Printf("Couldn't stop DHCP server: %s", err)
+	}
+}
+
+func getInput() (string, error) {
+	scanner := bufio.NewScanner(os.Stdin)
+	scanner.Scan()
+	text := scanner.Text()
+	err := scanner.Err()
+	return text, err
+}
+
+// command-line arguments
+type options struct {
+	verbose        bool   // is verbose logging enabled
+	configFilename string // path to the config file
+	bindHost       string // host address to bind HTTP server on
+	bindPort       int    // port to serve HTTP pages on
+	logFile        string // Path to the log file. If empty, write to stdout. If "syslog", writes to syslog
+
+	// service control action (see service.ControlAction array + "status" command)
+	serviceControlAction string
+}
+
+// loadOptions reads command line arguments and initializes configuration
+func loadOptions() options {
+	o := options{}
+
+	var printHelp func()
+	var opts = []struct {
+		longName          string
+		shortName         string
+		description       string
+		callbackWithValue func(value string)
+		callbackNoValue   func()
+	}{
+		{"config", "c", "path to config file", func(value string) { o.configFilename = value }, nil},
+		{"host", "o", "host address to bind HTTP server on", func(value string) { o.bindHost = value }, nil},
+		{"port", "p", "port to serve HTTP pages on", func(value string) {
+			v, err := strconv.Atoi(value)
+			if err != nil {
+				panic("Got port that is not a number")
+			}
+			o.bindPort = v
+		}, nil},
+		{"service", "s", "service control action: status, install, uninstall, start, stop, restart", func(value string) {
+			o.serviceControlAction = value
+		}, nil},
+		{"logfile", "l", "path to the log file. If empty, writes to stdout, if 'syslog' -- system log", func(value string) {
+			o.logFile = value
+		}, nil},
+		{"verbose", "v", "enable verbose output", nil, func() { o.verbose = true }},
+		{"help", "h", "print this help", nil, func() {
+			printHelp()
+			os.Exit(64)
+		}},
+	}
+	printHelp = func() {
+		fmt.Printf("Usage:\n\n")
+		fmt.Printf("%s [options]\n\n", os.Args[0])
+		fmt.Printf("Options:\n")
+		for _, opt := range opts {
+			fmt.Printf("  -%s, %-30s %s\n", opt.shortName, "--"+opt.longName, opt.description)
+		}
+	}
+	for i := 1; i < len(os.Args); i++ {
+		v := os.Args[i]
+		knownParam := false
+		for _, opt := range opts {
+			if v == "--"+opt.longName || v == "-"+opt.shortName {
+				if opt.callbackWithValue != nil {
+					if i+1 >= len(os.Args) {
+						log.Printf("ERROR: Got %s without argument\n", v)
+						os.Exit(64)
+					}
+					i++
+					opt.callbackWithValue(os.Args[i])
+				} else if opt.callbackNoValue != nil {
+					opt.callbackNoValue()
+				}
+				knownParam = true
+				break
+			}
+		}
+		if !knownParam {
+			log.Printf("ERROR: unknown option %v\n", v)
+			printHelp()
+			os.Exit(64)
+		}
+	}
+
+	return o
 }
 
 func promptAndGet(prompt string) (string, error) {

config.go

@@ -18,6 +18,12 @@ const (
 	filterDir = "filters" // cache location for downloaded filters, it's under DataDir
 )
 
+// logSettings
+type logSettings struct {
+	LogFile string `yaml:"log_file"` // Path to the log file. If empty, write to stdout. If "syslog", writes to syslog
+	Verbose bool   `yaml:"verbose"`  // If true, verbose logging is enabled
+}
+
 // configuration is loaded from YAML
 // field ordering is important -- yaml fields will mirror ordering from here
 type configuration struct {
@@ -34,6 +40,8 @@ type configuration struct {
 	UserRules []string           `yaml:"user_rules"`
 	DHCP      dhcpd.ServerConfig `yaml:"dhcp"`
 
+	logSettings `yaml:",inline"`
+
 	sync.RWMutex `yaml:"-"`
 
 	SchemaVersion int `yaml:"schema_version"` // keeping last so that users will be less tempted to change it -- used when upgrading between versions
@@ -79,20 +87,34 @@ var config = configuration{
 	SchemaVersion: currentSchemaVersion,
 }
 
-// Loads configuration from the YAML file
+// getLogSettings reads logging settings from the config file.
+// we do it in a separate method in order to configure logger before the actual configuration is parsed and applied.
+func getLogSettings() logSettings {
+	l := logSettings{}
+	yamlFile, err := readConfigFile()
+	if err != nil || yamlFile == nil {
+		return l
+	}
+	err = yaml.Unmarshal(yamlFile, &l)
+	if err != nil {
+		log.Printf("Couldn't get logging settings from the configuration: %s", err)
+	}
+	return l
+}
+
+// parseConfig loads configuration from the YAML file
 func parseConfig() error {
 	configFile := filepath.Join(config.ourBinaryDir, config.ourConfigFilename)
 	log.Printf("Reading YAML file: %s", configFile)
-	if _, err := os.Stat(configFile); os.IsNotExist(err) {
-		// do nothing, file doesn't exist
-		log.Printf("YAML file doesn't exist, skipping: %s", configFile)
-		return nil
-	}
-	yamlFile, err := ioutil.ReadFile(configFile)
+	yamlFile, err := readConfigFile()
 	if err != nil {
 		log.Printf("Couldn't read config file: %s", err)
 		return err
 	}
+	if yamlFile == nil {
+		log.Printf("YAML file doesn't exist, skipping it")
+		return nil
+	}
 	err = yaml.Unmarshal(yamlFile, &config)
 	if err != nil {
 		log.Printf("Couldn't parse config file: %s", err)
@@ -107,6 +129,16 @@ func parseConfig() error {
 	return nil
 }
 
+// readConfigFile reads config file contents if it exists
+func readConfigFile() ([]byte, error) {
+	configFile := filepath.Join(config.ourBinaryDir, config.ourConfigFilename)
+	if _, err := os.Stat(configFile); os.IsNotExist(err) {
+		// do nothing, file doesn't exist
+		return nil, nil
+	}
+	return ioutil.ReadFile(configFile)
+}
+
 // Saves configuration to the YAML file and also saves the user filter contents to a file
 func (c *configuration) write() error {
 	c.Lock()

dhcp.go

@@ -165,3 +165,20 @@ func startDHCPServer() error {
 	}
 	return nil
 }
+
+func stopDHCPServer() error {
+	if !config.DHCP.Enabled {
+		return nil
+	}
+
+	if !dhcpServer.Enabled {
+		return nil
+	}
+
+	err := dhcpServer.Stop()
+	if err != nil {
+		return errorx.Decorate(err, "Couldn't stop DHCP server")
+	}
+
+	return nil
+}

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/gobuffalo/packr v1.19.0
 	github.com/hmage/golibs v0.0.0-20181229160906-c8491df0bfc4
 	github.com/joomcode/errorx v0.1.0
+	github.com/kardianos/service v0.0.0-20181115005516-4c239ee84e7b
 	github.com/krolaw/dhcp4 v0.0.0-20180925202202-7cead472c414
 	github.com/miekg/dns v1.1.1
 	github.com/shirou/gopsutil v2.18.10+incompatible

go.sum

@@ -37,6 +37,8 @@ github.com/joho/godotenv v1.3.0 h1:Zjp+RcGpHhGlrMbJzXTrZZPrWj+1vfm90La1wgB6Bhc=
 github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=
 github.com/joomcode/errorx v0.1.0 h1:QmJMiI1DE1UFje2aI1ZWO/VMT5a32qBoXUclGOt8vsc=
 github.com/joomcode/errorx v0.1.0/go.mod h1:kgco15ekB6cs+4Xjzo7SPeXzx38PbJzBwbnu9qfVNHQ=
+github.com/kardianos/service v0.0.0-20181115005516-4c239ee84e7b h1:vfiqKno48aUndBMjTeWFpCExNnTf2Xnd6d228L4EfTQ=
+github.com/kardianos/service v0.0.0-20181115005516-4c239ee84e7b/go.mod h1:10UU/bEkzh2iEN6aYzbevY7J6p03KO5siTxQWXMEerg=
 github.com/krolaw/dhcp4 v0.0.0-20180925202202-7cead472c414 h1:6wnYc2S/lVM7BvR32BM74ph7bPgqMztWopMYKgVyEho=
 github.com/krolaw/dhcp4 v0.0.0-20180925202202-7cead472c414/go.mod h1:0AqAH3ZogsCrvrtUpvc6EtVKbc3w6xwZhkvGLuqyi3o=
 github.com/markbates/oncer v0.0.0-20181014194634-05fccaae8fc4 h1:Mlji5gkcpzkqTROyE4ZxZ8hN7osunMb2RuGVrbvMvCc=

service.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"os"
+
+	"github.com/hmage/golibs/log"
+	"github.com/kardianos/service"
+)
+
+// Represents the program that will be launched by a service or daemon
+type program struct {
+}
+
+// Start should quickly start the program
+func (p *program) Start(s service.Service) error {
+	// Start should not block. Do the actual work async.
+	args := options{}
+	go run(args)
+	return nil
+}
+
+// Stop stops the program
+func (p *program) Stop(s service.Service) error {
+	// Stop should not block. Return with a few seconds.
+	cleanup()
+	return nil
+}
+
+// handleServiceControlAction one of the possible control actions:
+// install -- installs a service/daemon
+// uninstall -- uninstalls it
+// status -- prints the service status
+// start -- starts the previously installed service
+// stop -- stops the previously installed service
+// restart - restarts the previously installed service
+func handleServiceControlAction(action string) {
+	log.Printf("Service control action: %s", action)
+
+	pwd, err := os.Getwd()
+	if err != nil {
+		log.Fatal("Unable to find the path to the current directory")
+	}
+	svcConfig := &service.Config{
+		Name:             "AdGuardHome",
+		DisplayName:      "AdGuard Home service",
+		Description:      "AdGuard Home: Network-level blocker",
+		WorkingDirectory: pwd,
+	}
+	prg := &program{}
+	s, err := service.New(prg, svcConfig)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	if action == "status" {
+		status, errSt := s.Status()
+		if errSt != nil {
+			log.Fatalf("failed to get service status: %s", errSt)
+		}
+
+		switch status {
+		case service.StatusUnknown:
+			log.Printf("Service status is unknown")
+		case service.StatusStopped:
+			log.Printf("Service is stopped")
+		case service.StatusRunning:
+			log.Printf("Service is running")
+		}
+	} else {
+		err = service.Control(s, action)
+		if err != nil {
+			log.Fatal(err)
+		}
+		log.Printf("Action %s has been done successfully", action)
+	}
+}