add filetransfer plugin.

internal/plugins/filetransfer/config.go

@@ -0,0 +1,41 @@
+package filetransfer
+
+import (
+	"path/filepath"
+	"time"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+type Config struct {
+	Enabled         bool
+	RootDir         string
+	RefreshInterval time.Duration
+}
+
+func (Config) Init(cmd *cobra.Command) error {
+	cmd.PersistentFlags().Bool("filetransfer.enabled", false, "whether file transfer is enabled")
+	if err := viper.BindPFlag("filetransfer.enabled", cmd.PersistentFlags().Lookup("filetransfer.enabled")); err != nil {
+		return err
+	}
+
+	cmd.PersistentFlags().String("filetransfer.dir", "/home/neko/Downloads", "root directory for file transfer")
+	if err := viper.BindPFlag("filetransfer.dir", cmd.PersistentFlags().Lookup("filetransfer.dir")); err != nil {
+		return err
+	}
+
+	cmd.PersistentFlags().Duration("filetransfer.refresh_interval", 30*time.Second, "interval to refresh file list")
+	if err := viper.BindPFlag("filetransfer.refresh_interval", cmd.PersistentFlags().Lookup("filetransfer.refresh_interval")); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (s *Config) Set() {
+	s.Enabled = viper.GetBool("filetransfer.enabled")
+	rootDir := viper.GetString("filetransfer.dir")
+	s.RootDir = filepath.Clean(rootDir)
+	s.RefreshInterval = viper.GetDuration("filetransfer.refresh_interval")
+}

internal/plugins/filetransfer/manager.go

@@ -0,0 +1,312 @@
+package filetransfer
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"regexp"
+	"sync"
+	"time"
+
+	"github.com/demodesk/neko/pkg/auth"
+	"github.com/demodesk/neko/pkg/types"
+	"github.com/demodesk/neko/pkg/utils"
+	"github.com/fsnotify/fsnotify"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+)
+
+const MULTIPART_FORM_MAX_MEMORY = 32 << 20
+
+func NewManager(
+	sessions types.SessionManager,
+	config *Config,
+) *Manager {
+	logger := log.With().Str("module", "filetransfer").Logger()
+
+	return &Manager{
+		logger:   logger,
+		config:   config,
+		sessions: sessions,
+		shutdown: make(chan struct{}),
+	}
+}
+
+type Manager struct {
+	logger   zerolog.Logger
+	config   *Config
+	sessions types.SessionManager
+	shutdown chan struct{}
+	mu       sync.RWMutex
+	fileList []Item
+}
+
+func (m *Manager) isEnabledForSession(session types.Session) bool {
+	canTransfer := true
+
+	profile, ok := session.Profile().Plugins["filetransfer"]
+	// by default, allow file transfer if the plugin config is not present
+	if ok {
+		canTransfer, ok = profile.(bool)
+		// if the plugin is present but not a boolean, allow file transfer
+		if !ok {
+			canTransfer = true
+		}
+	}
+
+	return m.config.Enabled && canTransfer
+	// TODO: when locking is implemented
+	// && (session.Profile().IsAdmin || !h.state.IsLocked("file_transfer"))
+}
+
+func (m *Manager) refresh() (error, bool) {
+	// if file transfer is disabled, return immediately without refreshing
+	if !m.config.Enabled {
+		return nil, false
+	}
+
+	files, err := ListFiles(m.config.RootDir)
+	if err != nil {
+		return err, false
+	}
+
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	// check if file list has changed (todo: use hash instead of comparing all fields)
+	changed := false
+	if len(files) == len(m.fileList) {
+		for i, file := range files {
+			if file.Name != m.fileList[i].Name || file.Size != m.fileList[i].Size {
+				changed = true
+				break
+			}
+		}
+	} else {
+		changed = true
+	}
+
+	m.fileList = files
+	return nil, changed
+}
+
+func (m *Manager) broadcastUpdate() {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+
+	m.sessions.Broadcast(FILETRANSFER_UPDATE, Message{
+		Enabled: m.config.Enabled,
+		RootDir: m.config.RootDir,
+		Files:   m.fileList,
+	})
+}
+
+func (m *Manager) Start() error {
+	// send init message once a user connects
+	m.sessions.OnConnected(func(session types.Session) {
+		isEnabled := m.isEnabledForSession(session)
+
+		// get file list
+		m.mu.RLock()
+		fileList := m.fileList
+		m.mu.RUnlock()
+
+		// send init message
+		session.Send(FILETRANSFER_UPDATE, Message{
+			Enabled: isEnabled,
+			RootDir: m.config.RootDir,
+			Files:   fileList,
+		})
+	})
+
+	// if file transfer is disabled, return immediately without starting the watcher
+	if !m.config.Enabled {
+		return nil
+	}
+
+	if _, err := os.Stat(m.config.RootDir); os.IsNotExist(err) {
+		err = os.Mkdir(m.config.RootDir, os.ModePerm)
+		m.logger.Err(err).Msg("creating file transfer directory")
+	}
+
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return fmt.Errorf("unable to start file transfer dir watcher: %w", err)
+	}
+
+	go func() {
+		defer watcher.Close()
+
+		// periodically refresh file list
+		ticker := time.NewTicker(m.config.RefreshInterval)
+		defer ticker.Stop()
+
+		for {
+			select {
+			case <-m.shutdown:
+				m.logger.Info().Msg("shutting down file transfer manager")
+				return
+			case <-ticker.C:
+				err, changed := m.refresh()
+				if err != nil {
+					m.logger.Err(err).Msg("unable to refresh file transfer list")
+				}
+				if changed {
+					m.broadcastUpdate()
+				}
+			case e, ok := <-watcher.Events:
+				if !ok {
+					m.logger.Info().Msg("file transfer dir watcher closed")
+					return
+				}
+
+				if e.Has(fsnotify.Create) || e.Has(fsnotify.Remove) || e.Has(fsnotify.Rename) {
+					m.logger.Debug().Str("event", e.String()).Msg("file transfer dir watcher event")
+
+					err, changed := m.refresh()
+					if err != nil {
+						m.logger.Err(err).Msg("unable to refresh file transfer list")
+					}
+
+					if changed {
+						m.broadcastUpdate()
+					}
+				}
+			case err := <-watcher.Errors:
+				m.logger.Err(err).Msg("error in file transfer dir watcher")
+			}
+		}
+	}()
+
+	if err := watcher.Add(m.config.RootDir); err != nil {
+		return fmt.Errorf("unable to watch file transfer dir: %w", err)
+	}
+
+	return nil
+}
+
+func (m *Manager) Shutdown() error {
+	close(m.shutdown)
+	return nil
+}
+
+func (m *Manager) Route(r types.Router) {
+	r.With(auth.AdminsOnly).Get("/", m.downloadFileHandler)
+	r.With(auth.AdminsOnly).Post("/", m.uploadFileHandler)
+}
+
+func (m *Manager) WebSocketHandler(session types.Session, msg types.WebSocketMessage) bool {
+	switch msg.Event {
+	case FILETRANSFER_UPDATE:
+		err, changed := m.refresh()
+		if err != nil {
+			m.logger.Err(err).Msg("unable to refresh file transfer list")
+		}
+
+		if changed {
+			m.broadcastUpdate()
+		} else {
+			// get file list
+			m.mu.RLock()
+			fileList := m.fileList
+			m.mu.RUnlock()
+
+			// send update message to this client only
+			session.Send(FILETRANSFER_UPDATE, Message{
+				Enabled: m.config.Enabled,
+				RootDir: m.config.RootDir,
+				Files:   fileList,
+			})
+		}
+		return true
+	}
+	return false
+}
+
+func (m *Manager) downloadFileHandler(w http.ResponseWriter, r *http.Request) error {
+	session, ok := auth.GetSession(r)
+	if !ok {
+		return utils.HttpUnauthorized("session not found")
+	}
+
+	enabled := m.isEnabledForSession(session)
+	if !enabled {
+		return utils.HttpForbidden("file transfer is disabled")
+	}
+
+	filename := r.URL.Query().Get("filename")
+	badChars, err := regexp.MatchString(`(?m)\.\.(?:\/|$)`, filename)
+	if filename == "" || badChars || err != nil {
+		return utils.HttpBadRequest().
+			WithInternalErr(err).
+			Msg("bad filename")
+	}
+
+	// ensure filename is clean and only contains the basename
+	filename = filepath.Clean(filename)
+	filename = filepath.Base(filename)
+	filePath := filepath.Join(m.config.RootDir, filename)
+
+	http.ServeFile(w, r, filePath)
+	return nil
+}
+
+func (m *Manager) uploadFileHandler(w http.ResponseWriter, r *http.Request) error {
+	session, ok := auth.GetSession(r)
+	if !ok {
+		return utils.HttpUnauthorized("session not found")
+	}
+
+	enabled := m.isEnabledForSession(session)
+	if !enabled {
+		return utils.HttpForbidden("file transfer is disabled")
+	}
+
+	err := r.ParseMultipartForm(MULTIPART_FORM_MAX_MEMORY)
+	if err != nil || r.MultipartForm == nil {
+		return utils.HttpBadRequest().
+			WithInternalErr(err).
+			Msg("error parsing form")
+	}
+
+	defer func() {
+		err = r.MultipartForm.RemoveAll()
+		if err != nil {
+			m.logger.Warn().Err(err).Msg("failed to clean up multipart form")
+		}
+	}()
+
+	for _, formheader := range r.MultipartForm.File["files"] {
+		// ensure filename is clean and only contains the basename
+		filename := filepath.Clean(formheader.Filename)
+		filename = filepath.Base(filename)
+		filePath := filepath.Join(m.config.RootDir, filename)
+
+		formfile, err := formheader.Open()
+		if err != nil {
+			return utils.HttpBadRequest().
+				WithInternalErr(err).
+				Msg("error opening formdata file")
+		}
+		defer formfile.Close()
+
+		f, err := os.OpenFile(filePath, os.O_WRONLY|os.O_CREATE, 0644)
+		if err != nil {
+			return utils.HttpInternalServerError().
+				WithInternalErr(err).
+				Msg("error opening file for writing")
+		}
+		defer f.Close()
+
+		_, err = io.Copy(f, formfile)
+		if err != nil {
+			return utils.HttpInternalServerError().
+				WithInternalErr(err).
+				Msg("error writing file")
+		}
+	}
+
+	return nil
+}

internal/plugins/filetransfer/plugin.go

@@ -0,0 +1,35 @@
+package filetransfer
+
+import (
+	"github.com/demodesk/neko/pkg/types"
+)
+
+type Plugin struct {
+	config  *Config
+	manager *Manager
+}
+
+func NewPlugin() *Plugin {
+	return &Plugin{
+		config: &Config{},
+	}
+}
+
+func (p *Plugin) Name() string {
+	return PluginName
+}
+
+func (p *Plugin) Config() types.PluginConfig {
+	return p.config
+}
+
+func (p *Plugin) Start(m types.PluginManagers) error {
+	p.manager = NewManager(m.SessionManager, p.config)
+	m.ApiManager.AddRouter("/filetransfer", p.manager.Route)
+	m.WebSocketManager.AddHandler(p.manager.WebSocketHandler)
+	return p.manager.Start()
+}
+
+func (p *Plugin) Shutdown() error {
+	return p.manager.Shutdown()
+}

internal/plugins/filetransfer/types.go

@@ -0,0 +1,26 @@
+package filetransfer
+
+const PluginName = "filetransfer"
+
+const (
+	FILETRANSFER_UPDATE = "filetransfer/update"
+)
+
+type Message struct {
+	Enabled bool   `json:"enabled"`
+	RootDir string `json:"root_dir"`
+	Files   []Item `json:"files"`
+}
+
+type ItemType string
+
+const (
+	ItemTypeFile ItemType = "file"
+	ItemTypeDir  ItemType = "dir"
+)
+
+type Item struct {
+	Name string   `json:"name"`
+	Type ItemType `json:"type"`
+	Size int64    `json:"size,omitempty"`
+}

internal/plugins/filetransfer/utils.go

@@ -0,0 +1,32 @@
+package filetransfer
+
+import "os"
+
+func ListFiles(path string) ([]Item, error) {
+	items, err := os.ReadDir(path)
+	if err != nil {
+		return nil, err
+	}
+
+	out := make([]Item, len(items))
+	for i, item := range items {
+		var itemType ItemType
+		var size int64 = 0
+		if item.IsDir() {
+			itemType = ItemTypeDir
+		} else {
+			itemType = ItemTypeFile
+			info, err := item.Info()
+			if err == nil {
+				size = info.Size()
+			}
+		}
+		out[i] = Item{
+			Name: item.Name(),
+			Type: itemType,
+			Size: size,
+		}
+	}
+
+	return out, nil
+}

internal/plugins/manager.go

@@ -11,6 +11,7 @@ import (
 	"github.com/spf13/cobra"
 
 	"github.com/demodesk/neko/internal/config"
+	"github.com/demodesk/neko/internal/plugins/filetransfer"
 	"github.com/demodesk/neko/pkg/types"
 )
 
@@ -42,6 +43,9 @@ func New(config *config.Plugins) *ManagerCtx {
 		manager.logger.Info().Msgf("loading finished, total %d plugins", manager.plugins.len())
 	}
 
+	// add built-in plugins
+	manager.plugins.addPlugin(filetransfer.NewPlugin())
+
 	return manager
 }