"bufio"
"bytes"
"context"
+ "crypto/rand"
"encoding/binary"
"errors"
"fmt"
- "github.com/go-playground/validator/v10"
"golang.org/x/text/encoding/charmap"
- "gopkg.in/yaml.v3"
"io"
- "io/fs"
"log"
"log/slog"
- "math/big"
- "math/rand"
"net"
- "os"
- "path"
- "path/filepath"
"strings"
"sync"
"time"
var txtEncoder = charmap.Macintosh.NewEncoder()
type Server struct {
- NetInterface string
- Port int
- Accounts map[string]*Account
- Agreement []byte
- Clients map[uint16]*ClientConn
- fileTransfers map[[4]byte]*FileTransfer
-
- Config *Config
- ConfigDir string
- Logger *slog.Logger
- banner []byte
-
- PrivateChatsMu sync.Mutex
- PrivateChats map[uint32]*PrivateChat
-
- NextGuestID *uint16
+ NetInterface string
+ Port int
+
+ handlers map[TranType]HandlerFunc
+
+ Config Config
+ Logger *slog.Logger
+
TrackerPassID [4]byte
- StatsMu sync.Mutex
- Stats *Stats
+ Stats Counter
FS FileStore // Storage backend to use for File storage
outbox chan Transaction
- mux sync.Mutex
- threadedNewsMux sync.Mutex
- ThreadedNews *ThreadedNews
+ Agreement io.ReadSeeker
+ Banner []byte
+
+ FileTransferMgr FileTransferMgr
+ ChatMgr ChatManager
+ ClientMgr ClientManager
+ AccountManager AccountManager
+ ThreadedNewsMgr ThreadedNewsMgr
+ BanList BanMgr
+
+ MessageBoard io.ReadWriteSeeker
+}
+
+type Option = func(s *Server)
- flatNewsMux sync.Mutex
- FlatNews []byte
+func WithConfig(config Config) func(s *Server) {
+ return func(s *Server) {
+ s.Config = config
+ }
+}
- banListMU sync.Mutex
- banList map[string]*time.Time
+func WithLogger(logger *slog.Logger) func(s *Server) {
+ return func(s *Server) {
+ s.Logger = logger
+ }
}
-func (s *Server) CurrentStats() Stats {
- s.StatsMu.Lock()
- defer s.StatsMu.Unlock()
+// WithPort optionally overrides the default TCP port.
+func WithPort(port int) func(s *Server) {
+ return func(s *Server) {
+ s.Port = port
+ }
+}
- stats := s.Stats
- stats.CurrentlyConnected = len(s.Clients)
+// WithInterface optionally sets a specific interface to listen on.
+func WithInterface(netInterface string) func(s *Server) {
+ return func(s *Server) {
+ s.NetInterface = netInterface
+ }
+}
- return *stats
+type ServerConfig struct {
+}
+
+func NewServer(options ...Option) (*Server, error) {
+ server := Server{
+ handlers: make(map[TranType]HandlerFunc),
+ outbox: make(chan Transaction),
+ FS: &OSFileStore{},
+ ChatMgr: NewMemChatManager(),
+ ClientMgr: NewMemClientMgr(),
+ FileTransferMgr: NewMemFileTransferMgr(),
+ Stats: NewStats(),
+ }
+
+ for _, opt := range options {
+ opt(&server)
+ }
+
+ // generate a new random passID for tracker registration
+ _, err := rand.Read(server.TrackerPassID[:])
+ if err != nil {
+ return nil, err
+ }
+
+ return &server, nil
}
-type PrivateChat struct {
- Subject string
- ClientConn map[uint16]*ClientConn
+func (s *Server) CurrentStats() map[string]interface{} {
+ return s.Stats.Values()
}
-func (s *Server) ListenAndServe(ctx context.Context, cancelRoot context.CancelFunc) error {
+func (s *Server) ListenAndServe(ctx context.Context) error {
+ go s.registerWithTrackers(ctx)
+ go s.keepaliveHandler(ctx)
+ go s.processOutbox()
+
var wg sync.WaitGroup
wg.Add(1)
defer func() { _ = conn.Close() }()
err = s.handleFileTransfer(
- context.WithValue(ctx, contextKeyReq, requestCtx{
- remoteAddr: conn.RemoteAddr().String(),
- }),
+ context.WithValue(ctx, contextKeyReq, requestCtx{remoteAddr: conn.RemoteAddr().String()}),
conn,
)
}
func (s *Server) sendTransaction(t Transaction) error {
- clientID, err := byteToInt(*t.clientID)
- if err != nil {
- return fmt.Errorf("invalid client ID: %v", err)
- }
+ client := s.ClientMgr.Get(t.ClientID)
- s.mux.Lock()
- client, ok := s.Clients[uint16(clientID)]
- s.mux.Unlock()
- if !ok || client == nil {
- return fmt.Errorf("invalid client id %v", *t.clientID)
+ if client == nil {
+ return nil
}
- _, err = io.Copy(client.Connection, &t)
+ _, err := io.Copy(client.Connection, &t)
if err != nil {
- return fmt.Errorf("failed to send transaction to client %v: %v", clientID, err)
+ return fmt.Errorf("failed to send transaction to client %v: %v", t.ClientID, err)
}
return nil
}
func (s *Server) Serve(ctx context.Context, ln net.Listener) error {
- go s.processOutbox()
-
for {
- conn, err := ln.Accept()
- if err != nil {
- s.Logger.Error("error accepting connection", "err", err)
- }
- connCtx := context.WithValue(ctx, contextKeyReq, requestCtx{
- remoteAddr: conn.RemoteAddr().String(),
- })
-
- go func() {
- s.Logger.Info("Connection established", "RemoteAddr", conn.RemoteAddr())
-
- defer conn.Close()
- if err := s.handleNewConnection(connCtx, conn, conn.RemoteAddr().String()); err != nil {
- if err == io.EOF {
- s.Logger.Info("Client disconnected", "RemoteAddr", conn.RemoteAddr())
- } else {
- s.Logger.Error("error serving request", "RemoteAddr", conn.RemoteAddr(), "err", err)
- }
+ select {
+ case <-ctx.Done():
+ s.Logger.Info("Server shutting down")
+ return ctx.Err()
+ default:
+ conn, err := ln.Accept()
+ if err != nil {
+ s.Logger.Error("Error accepting connection", "err", err)
+ continue
}
- }()
- }
-}
-
-const (
- agreementFile = "Agreement.txt"
-)
-
-// NewServer constructs a new Server from a config dir
-func NewServer(configDir, netInterface string, netPort int, logger *slog.Logger, fs FileStore) (*Server, error) {
- server := Server{
- NetInterface: netInterface,
- Port: netPort,
- Accounts: make(map[string]*Account),
- Config: new(Config),
- Clients: make(map[uint16]*ClientConn),
- fileTransfers: make(map[[4]byte]*FileTransfer),
- PrivateChats: make(map[uint32]*PrivateChat),
- ConfigDir: configDir,
- Logger: logger,
- NextGuestID: new(uint16),
- outbox: make(chan Transaction),
- Stats: &Stats{Since: time.Now()},
- ThreadedNews: &ThreadedNews{},
- FS: fs,
- banList: make(map[string]*time.Time),
- }
-
- var err error
-
- // generate a new random passID for tracker registration
- if _, err := rand.Read(server.TrackerPassID[:]); err != nil {
- return nil, err
- }
-
- server.Agreement, err = os.ReadFile(filepath.Join(configDir, agreementFile))
- if err != nil {
- return nil, err
- }
- if server.FlatNews, err = os.ReadFile(filepath.Join(configDir, "MessageBoard.txt")); err != nil {
- return nil, err
- }
-
- // try to load the ban list, but ignore errors as this file may not be present or may be empty
- _ = server.loadBanList(filepath.Join(configDir, "Banlist.yaml"))
-
- if err := server.loadThreadedNews(filepath.Join(configDir, "ThreadedNews.yaml")); err != nil {
- return nil, fmt.Errorf("error loading threaded news: %w", err)
- }
-
- if err := server.loadConfig(filepath.Join(configDir, "config.yaml")); err != nil {
- return nil, err
- }
-
- if err := server.loadAccounts(filepath.Join(configDir, "Users/")); err != nil {
- return nil, err
- }
+ go func() {
+ connCtx := context.WithValue(ctx, contextKeyReq, requestCtx{
+ remoteAddr: conn.RemoteAddr().String(),
+ })
- // If the FileRoot is an absolute path, use it, otherwise treat as a relative path to the config dir.
- if !filepath.IsAbs(server.Config.FileRoot) {
- server.Config.FileRoot = filepath.Join(configDir, server.Config.FileRoot)
- }
+ s.Logger.Info("Connection established", "addr", conn.RemoteAddr())
+ defer conn.Close()
- server.banner, err = os.ReadFile(filepath.Join(server.ConfigDir, server.Config.BannerFile))
- if err != nil {
- return nil, fmt.Errorf("error opening banner: %w", err)
+ if err := s.handleNewConnection(connCtx, conn, conn.RemoteAddr().String()); err != nil {
+ if err == io.EOF {
+ s.Logger.Info("Client disconnected", "RemoteAddr", conn.RemoteAddr())
+ } else {
+ s.Logger.Error("Error serving request", "RemoteAddr", conn.RemoteAddr(), "err", err)
+ }
+ }
+ }()
+ }
}
+}
- *server.NextGuestID = 1
+// time in seconds between tracker re-registration
+const trackerUpdateFrequency = 300
- if server.Config.EnableTrackerRegistration {
- server.Logger.Info(
- "Tracker registration enabled",
- "frequency", fmt.Sprintf("%vs", trackerUpdateFrequency),
- "trackers", server.Config.Trackers,
- )
+// registerWithTrackers runs every trackerUpdateFrequency seconds to update the server's tracker entry on all configured
+// trackers.
+func (s *Server) registerWithTrackers(ctx context.Context) {
+ ticker := time.NewTicker(trackerUpdateFrequency * time.Second)
+ defer ticker.Stop()
- go func() {
- for {
+ for {
+ select {
+ case <-ctx.Done():
+ return
+ case <-ticker.C:
+ if s.Config.EnableTrackerRegistration {
tr := &TrackerRegistration{
- UserCount: server.userCount(),
- PassID: server.TrackerPassID,
- Name: server.Config.Name,
- Description: server.Config.Description,
+ UserCount: len(s.ClientMgr.List()),
+ PassID: s.TrackerPassID,
+ Name: s.Config.Name,
+ Description: s.Config.Description,
}
- binary.BigEndian.PutUint16(tr.Port[:], uint16(server.Port))
- for _, t := range server.Config.Trackers {
- if err := register(t, tr); err != nil {
- server.Logger.Error("unable to register with tracker %v", "error", err)
+ binary.BigEndian.PutUint16(tr.Port[:], uint16(s.Port))
+
+ for _, t := range s.Config.Trackers {
+ if err := register(&RealDialer{}, t, tr); err != nil {
+ s.Logger.Error(fmt.Sprintf("Unable to register with tracker %v", t), "error", err)
}
- server.Logger.Debug("Sent Tracker registration", "addr", t)
}
-
- time.Sleep(trackerUpdateFrequency * time.Second)
}
- }()
+ }
}
- // Start Client Keepalive go routine
- go server.keepaliveHandler()
-
- return &server, nil
}
-func (s *Server) userCount() int {
- s.mux.Lock()
- defer s.mux.Unlock()
+const (
+ userIdleSeconds = 300 // time in seconds before an inactive user is marked idle
+ idleCheckInterval = 10 // time in seconds to check for idle users
+)
- return len(s.Clients)
-}
+// keepaliveHandler runs every idleCheckInterval seconds and increments a user's idle time by idleCheckInterval seconds.
+// If the updated idle time exceeds userIdleSeconds and the user was not previously idle, we notify all connected clients
+// that the user has gone idle. For most clients, this turns the user grey in the user list.
+func (s *Server) keepaliveHandler(ctx context.Context) {
+ ticker := time.NewTicker(idleCheckInterval * time.Second)
+ defer ticker.Stop()
-func (s *Server) keepaliveHandler() {
for {
- time.Sleep(idleCheckInterval * time.Second)
- s.mux.Lock()
-
- for _, c := range s.Clients {
- c.IdleTime += idleCheckInterval
- if c.IdleTime > userIdleSeconds && !c.Idle {
- c.Idle = true
-
- flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(c.Flags)))
- flagBitmap.SetBit(flagBitmap, UserFlagAway, 1)
- binary.BigEndian.PutUint16(c.Flags, uint16(flagBitmap.Int64()))
-
- c.sendAll(
- TranNotifyChangeUser,
- NewField(FieldUserID, *c.ID),
- NewField(FieldUserFlags, c.Flags),
- NewField(FieldUserName, c.UserName),
- NewField(FieldUserIconID, c.Icon),
- )
+ select {
+ case <-ctx.Done():
+ return
+ case <-ticker.C:
+ for _, c := range s.ClientMgr.List() {
+ c.mu.Lock()
+ c.IdleTime += idleCheckInterval
+
+ // Check if the user
+ if c.IdleTime > userIdleSeconds && !c.Flags.IsSet(UserFlagAway) {
+ c.Flags.Set(UserFlagAway, 1)
+
+ c.SendAll(
+ TranNotifyChangeUser,
+ NewField(FieldUserID, c.ID[:]),
+ NewField(FieldUserFlags, c.Flags[:]),
+ NewField(FieldUserName, c.UserName),
+ NewField(FieldUserIconID, c.Icon),
+ )
+ }
+ c.mu.Unlock()
}
}
- s.mux.Unlock()
- }
-}
-
-func (s *Server) writeBanList() error {
- s.banListMU.Lock()
- defer s.banListMU.Unlock()
-
- out, err := yaml.Marshal(s.banList)
- if err != nil {
- return err
}
- err = os.WriteFile(
- filepath.Join(s.ConfigDir, "Banlist.yaml"),
- out,
- 0666,
- )
- return err
-}
-
-func (s *Server) writeThreadedNews() error {
- s.threadedNewsMux.Lock()
- defer s.threadedNewsMux.Unlock()
-
- out, err := yaml.Marshal(s.ThreadedNews)
- if err != nil {
- return err
- }
- err = s.FS.WriteFile(
- filepath.Join(s.ConfigDir, "ThreadedNews.yaml"),
- out,
- 0666,
- )
- return err
}
func (s *Server) NewClientConn(conn io.ReadWriteCloser, remoteAddr string) *ClientConn {
- s.mux.Lock()
- defer s.mux.Unlock()
-
clientConn := &ClientConn{
- ID: &[]byte{0, 0},
- Icon: []byte{0, 0},
- Flags: []byte{0, 0},
- UserName: []byte{},
+ Icon: []byte{0, 0}, // TODO: make array type
Connection: conn,
Server: s,
- Version: []byte{},
- AutoReply: []byte{},
RemoteAddr: remoteAddr,
- transfers: map[int]map[[4]byte]*FileTransfer{
- FileDownload: {},
- FileUpload: {},
- FolderDownload: {},
- FolderUpload: {},
- bannerDownload: {},
- },
- }
- *s.NextGuestID++
- ID := *s.NextGuestID
+ ClientFileTransferMgr: NewClientFileTransferMgr(),
+ }
- binary.BigEndian.PutUint16(*clientConn.ID, ID)
- s.Clients[ID] = clientConn
+ s.ClientMgr.Add(clientConn)
return clientConn
}
-// NewUser creates a new user account entry in the server map and config file
-func (s *Server) NewUser(login, name, password string, access accessBitmap) error {
- s.mux.Lock()
- defer s.mux.Unlock()
-
- account := Account{
- Login: login,
- Name: name,
- Password: hashAndSalt([]byte(password)),
- Access: access,
- }
- out, err := yaml.Marshal(&account)
- if err != nil {
- return err
- }
-
- // Create account file, returning an error if one already exists.
- file, err := os.OpenFile(
- filepath.Join(s.ConfigDir, "Users", path.Join("/", login)+".yaml"),
- os.O_CREATE|os.O_EXCL|os.O_WRONLY,
- 0644,
+func sendBanMessage(rwc io.Writer, message string) {
+ t := NewTransaction(
+ TranServerMsg,
+ [2]byte{0, 0},
+ NewField(FieldData, []byte(message)),
+ NewField(FieldChatOptions, []byte{0, 0}),
)
- if err != nil {
- return err
- }
- defer file.Close()
-
- _, err = file.Write(out)
- if err != nil {
- return fmt.Errorf("error writing account file: %w", err)
- }
-
- s.Accounts[login] = &account
-
- return nil
+ _, _ = io.Copy(rwc, &t)
+ time.Sleep(1 * time.Second)
}
-func (s *Server) UpdateUser(login, newLogin, name, password string, access accessBitmap) error {
- s.mux.Lock()
- defer s.mux.Unlock()
-
- // update renames the user login
- if login != newLogin {
- err := os.Rename(filepath.Join(s.ConfigDir, "Users", path.Join("/", login)+".yaml"), filepath.Join(s.ConfigDir, "Users", path.Join("/", newLogin)+".yaml"))
- if err != nil {
- return fmt.Errorf("unable to rename account: %w", err)
- }
- s.Accounts[newLogin] = s.Accounts[login]
- s.Accounts[newLogin].Login = newLogin
- delete(s.Accounts, login)
- }
-
- account := s.Accounts[newLogin]
- account.Access = access
- account.Name = name
- account.Password = password
-
- out, err := yaml.Marshal(&account)
- if err != nil {
- return err
- }
-
- if err := os.WriteFile(filepath.Join(s.ConfigDir, "Users", newLogin+".yaml"), out, 0666); err != nil {
- return err
- }
-
- return nil
-}
-
-// DeleteUser deletes the user account
-func (s *Server) DeleteUser(login string) error {
- s.mux.Lock()
- defer s.mux.Unlock()
+// handleNewConnection takes a new net.Conn and performs the initial login sequence
+func (s *Server) handleNewConnection(ctx context.Context, rwc io.ReadWriteCloser, remoteAddr string) error {
+ defer dontPanic(s.Logger)
- err := s.FS.Remove(filepath.Join(s.ConfigDir, "Users", path.Join("/", login)+".yaml"))
- if err != nil {
- return err
+ if err := performHandshake(rwc); err != nil {
+ return fmt.Errorf("perform handshake: %w", err)
}
- delete(s.Accounts, login)
-
- return nil
-}
-
-func (s *Server) connectedUsers() []Field {
- s.mux.Lock()
- defer s.mux.Unlock()
-
- var connectedUsers []Field
- for _, c := range sortedClients(s.Clients) {
- b, err := io.ReadAll(&User{
- ID: *c.ID,
- Icon: c.Icon,
- Flags: c.Flags,
- Name: string(c.UserName),
- })
- if err != nil {
+ // Check if remoteAddr is present in the ban list
+ ipAddr := strings.Split(remoteAddr, ":")[0]
+ if isBanned, banUntil := s.BanList.IsBanned(ipAddr); isBanned {
+ // permaban
+ if banUntil == nil {
+ sendBanMessage(rwc, "You are permanently banned on this server")
+ s.Logger.Debug("Disconnecting permanently banned IP", "remoteAddr", ipAddr)
return nil
}
- connectedUsers = append(connectedUsers, NewField(FieldUsernameWithInfo, b))
- }
- return connectedUsers
-}
-
-func (s *Server) loadBanList(path string) error {
- fh, err := os.Open(path)
- if err != nil {
- return err
- }
- decoder := yaml.NewDecoder(fh)
-
- return decoder.Decode(s.banList)
-}
-// loadThreadedNews loads the threaded news data from disk
-func (s *Server) loadThreadedNews(threadedNewsPath string) error {
- fh, err := os.Open(threadedNewsPath)
- if err != nil {
- return err
- }
- decoder := yaml.NewDecoder(fh)
-
- return decoder.Decode(s.ThreadedNews)
-}
-
-// loadAccounts loads account data from disk
-func (s *Server) loadAccounts(userDir string) error {
- matches, err := filepath.Glob(filepath.Join(userDir, "*.yaml"))
- if err != nil {
- return err
- }
-
- if len(matches) == 0 {
- return errors.New("no user accounts found in " + userDir)
- }
-
- for _, file := range matches {
- fh, err := s.FS.Open(file)
- if err != nil {
- return err
- }
-
- account := Account{}
- decoder := yaml.NewDecoder(fh)
- if err = decoder.Decode(&account); err != nil {
- return fmt.Errorf("error loading account %s: %w", file, err)
+ // temporary ban
+ if time.Now().Before(*banUntil) {
+ sendBanMessage(rwc, "You are temporarily banned on this server")
+ s.Logger.Debug("Disconnecting temporarily banned IP", "remoteAddr", ipAddr)
+ return nil
}
-
- s.Accounts[account.Login] = &account
- }
- return nil
-}
-
-func (s *Server) loadConfig(path string) error {
- fh, err := s.FS.Open(path)
- if err != nil {
- return err
- }
-
- decoder := yaml.NewDecoder(fh)
- err = decoder.Decode(s.Config)
- if err != nil {
- return err
- }
-
- validate := validator.New()
- err = validate.Struct(s.Config)
- if err != nil {
- return err
- }
- return nil
-}
-
-// handleNewConnection takes a new net.Conn and performs the initial login sequence
-func (s *Server) handleNewConnection(ctx context.Context, rwc io.ReadWriteCloser, remoteAddr string) error {
- defer dontPanic(s.Logger)
-
- if err := Handshake(rwc); err != nil {
- return err
}
// Create a new scanner for parsing incoming bytes into transaction tokens
var clientLogin Transaction
if _, err := clientLogin.Write(buf); err != nil {
- return err
- }
-
- // check if remoteAddr is present in the ban list
- if banUntil, ok := s.banList[strings.Split(remoteAddr, ":")[0]]; ok {
- // permaban
- if banUntil == nil {
- t := NewTransaction(
- TranServerMsg,
- &[]byte{0, 0},
- NewField(FieldData, []byte("You are permanently banned on this server")),
- NewField(FieldChatOptions, []byte{0, 0}),
- )
-
- _, err := io.Copy(rwc, t)
- if err != nil {
- return err
- }
-
- time.Sleep(1 * time.Second)
- return nil
- }
-
- // temporary ban
- if time.Now().Before(*banUntil) {
- t := NewTransaction(
- TranServerMsg,
- &[]byte{0, 0},
- NewField(FieldData, []byte("You are temporarily banned on this server")),
- NewField(FieldChatOptions, []byte{0, 0}),
- )
-
- _, err := io.Copy(rwc, t)
- if err != nil {
- return err
- }
-
- time.Sleep(1 * time.Second)
- return nil
- }
+ return fmt.Errorf("error writing login transaction: %w", err)
}
c := s.NewClientConn(rwc, remoteAddr)
defer c.Disconnect()
- encodedLogin := clientLogin.GetField(FieldUserLogin).Data
encodedPassword := clientLogin.GetField(FieldUserPassword).Data
c.Version = clientLogin.GetField(FieldVersion).Data
- var login string
- for _, char := range encodedLogin {
- login += string(rune(255 - uint(char)))
- }
+ login := clientLogin.GetField(FieldUserLogin).DecodeObfuscatedString()
if login == "" {
login = GuestAccount
}
- c.logger = s.Logger.With("remoteAddr", remoteAddr, "login", login)
+ c.Logger = s.Logger.With("ip", ipAddr, "login", login)
// If authentication fails, send error reply and close connection
if !c.Authenticate(login, encodedPassword) {
- t := c.NewErrReply(&clientLogin, "Incorrect login.")
+ t := c.NewErrReply(&clientLogin, "Incorrect login.")[0]
_, err := io.Copy(rwc, &t)
if err != nil {
return err
}
- c.logger.Info("Login failed", "clientVersion", fmt.Sprintf("%x", c.Version))
+ c.Logger.Info("Login failed", "clientVersion", fmt.Sprintf("%x", c.Version))
return nil
}
c.Icon = clientLogin.GetField(FieldUserIconID).Data
}
- c.Account = c.Server.Accounts[login]
+ c.Account = c.Server.AccountManager.Get(login)
+ if c.Account == nil {
+ return nil
+ }
if clientLogin.GetField(FieldUserName).Data != nil {
- if c.Authorize(accessAnyName) {
+ if c.Authorize(AccessAnyName) {
c.UserName = clientLogin.GetField(FieldUserName).Data
} else {
c.UserName = []byte(c.Account.Name)
}
}
- if c.Authorize(accessDisconUser) {
- c.Flags = []byte{0, 2}
+ if c.Authorize(AccessDisconUser) {
+ c.Flags.Set(UserFlagAdmin, 1)
}
s.outbox <- c.NewReply(&clientLogin,
)
// Send user access privs so client UI knows how to behave
- c.Server.outbox <- *NewTransaction(TranUserAccess, c.ID, NewField(FieldUserAccess, c.Account.Access[:]))
+ c.Server.outbox <- NewTransaction(TranUserAccess, c.ID, NewField(FieldUserAccess, c.Account.Access[:]))
- // Accounts with accessNoAgreement do not receive the server agreement on login. The behavior is different between
+ // Accounts with AccessNoAgreement do not receive the server agreement on login. The behavior is different between
// client versions. For 1.2.3 client, we do not send TranShowAgreement. For other client versions, we send
// TranShowAgreement but with the NoServerAgreement field set to 1.
- if c.Authorize(accessNoAgreement) {
+ if c.Authorize(AccessNoAgreement) {
// If client version is nil, then the client uses the 1.2.3 login behavior
if c.Version != nil {
- c.Server.outbox <- *NewTransaction(TranShowAgreement, c.ID, NewField(FieldNoServerAgreement, []byte{1}))
+ c.Server.outbox <- NewTransaction(TranShowAgreement, c.ID, NewField(FieldNoServerAgreement, []byte{1}))
}
} else {
- c.Server.outbox <- *NewTransaction(TranShowAgreement, c.ID, NewField(FieldData, s.Agreement))
+ _, _ = c.Server.Agreement.Seek(0, 0)
+ data, _ := io.ReadAll(c.Server.Agreement)
+
+ c.Server.outbox <- NewTransaction(TranShowAgreement, c.ID, NewField(FieldData, data))
}
// If the client has provided a username as part of the login, we can infer that it is using the 1.2.3 login
if len(c.UserName) != 0 {
// Add the client username to the logger. For 1.5+ clients, we don't have this information yet as it comes as
// part of TranAgreed
- c.logger = c.logger.With("Name", string(c.UserName))
-
- c.logger.Info("Login successful", "clientVersion", "Not sent (probably 1.2.3)")
+ c.Logger = c.Logger.With("name", string(c.UserName))
+ c.Logger.Info("Login successful")
// Notify other clients on the server that the new user has logged in. For 1.5+ clients we don't have this
// information yet, so we do it in TranAgreed instead
- for _, t := range c.notifyOthers(
- *NewTransaction(
- TranNotifyChangeUser, nil,
+ for _, t := range c.NotifyOthers(
+ NewTransaction(
+ TranNotifyChangeUser, [2]byte{0, 0},
NewField(FieldUserName, c.UserName),
- NewField(FieldUserID, *c.ID),
+ NewField(FieldUserID, c.ID[:]),
NewField(FieldUserIconID, c.Icon),
- NewField(FieldUserFlags, c.Flags),
+ NewField(FieldUserFlags, c.Flags[:]),
),
) {
c.Server.outbox <- t
}
}
- c.Server.Stats.ConnectionCounter += 1
- if len(s.Clients) > c.Server.Stats.ConnectionPeak {
- c.Server.Stats.ConnectionPeak = len(s.Clients)
+ c.Server.Stats.Increment(StatConnectionCounter, StatCurrentlyConnected)
+ defer c.Server.Stats.Decrement(StatCurrentlyConnected)
+
+ if len(s.ClientMgr.List()) > c.Server.Stats.Get(StatConnectionPeak) {
+ c.Server.Stats.Set(StatConnectionPeak, len(s.ClientMgr.List()))
}
// Scan for new transactions and handle them as they come in.
for scanner.Scan() {
- // Make a new []byte slice and copy the scanner bytes to it. This is critical to avoid a data race as the
- // scanner re-uses the buffer for subsequent scans.
- buf := make([]byte, len(scanner.Bytes()))
- copy(buf, scanner.Bytes())
+ // Copy the scanner bytes to a new slice to it to avoid a data race when the scanner re-uses the buffer.
+ tmpBuf := make([]byte, len(scanner.Bytes()))
+ copy(tmpBuf, scanner.Bytes())
var t Transaction
- if _, err := t.Write(buf); err != nil {
+ if _, err := t.Write(tmpBuf); err != nil {
return err
}
- if err := c.handleTransaction(t); err != nil {
- c.logger.Error("Error handling transaction", "err", err)
- }
+ c.handleTransaction(t)
}
return nil
}
-func (s *Server) NewPrivateChat(cc *ClientConn) []byte {
- s.PrivateChatsMu.Lock()
- defer s.PrivateChatsMu.Unlock()
-
- randID := make([]byte, 4)
- rand.Read(randID)
- data := binary.BigEndian.Uint32(randID)
-
- s.PrivateChats[data] = &PrivateChat{
- ClientConn: make(map[uint16]*ClientConn),
- }
- s.PrivateChats[data].ClientConn[cc.uint16ID()] = cc
-
- return randID
-}
-
-const dlFldrActionSendFile = 1
-const dlFldrActionResumeFile = 2
-const dlFldrActionNextFile = 3
-
// handleFileTransfer receives a client net.Conn from the file transfer server, performs the requested transfer type, then closes the connection
func (s *Server) handleFileTransfer(ctx context.Context, rwc io.ReadWriter) error {
defer dontPanic(s.Logger)
- txBuf := make([]byte, 16)
- if _, err := io.ReadFull(rwc, txBuf); err != nil {
- return err
+ // The first 16 bytes contain the file transfer.
+ var t transfer
+ if _, err := io.CopyN(&t, rwc, 16); err != nil {
+ return fmt.Errorf("error reading file transfer: %w", err)
}
- var t transfer
- if _, err := t.Write(txBuf); err != nil {
- return err
+ fileTransfer := s.FileTransferMgr.Get(t.ReferenceNumber)
+ if fileTransfer == nil {
+ return errors.New("invalid transaction ID")
}
defer func() {
- s.mux.Lock()
- delete(s.fileTransfers, t.ReferenceNumber)
- s.mux.Unlock()
+ s.FileTransferMgr.Delete(t.ReferenceNumber)
// Wait a few seconds before closing the connection: this is a workaround for problems
// observed with Windows clients where the client must initiate close of the TCP connection before
time.Sleep(3 * time.Second)
}()
- s.mux.Lock()
- fileTransfer, ok := s.fileTransfers[t.ReferenceNumber]
- s.mux.Unlock()
- if !ok {
- return errors.New("invalid transaction ID")
- }
-
- defer func() {
- fileTransfer.ClientConn.transfersMU.Lock()
- delete(fileTransfer.ClientConn.transfers[fileTransfer.Type], t.ReferenceNumber)
- fileTransfer.ClientConn.transfersMU.Unlock()
- }()
-
rLogger := s.Logger.With(
"remoteAddr", ctx.Value(contextKeyReq).(requestCtx).remoteAddr,
"login", fileTransfer.ClientConn.Account.Login,
"Name", string(fileTransfer.ClientConn.UserName),
)
- fullPath, err := readPath(s.Config.FileRoot, fileTransfer.FilePath, fileTransfer.FileName)
+ fullPath, err := ReadPath(s.Config.FileRoot, fileTransfer.FilePath, fileTransfer.FileName)
if err != nil {
return err
}
switch fileTransfer.Type {
- case bannerDownload:
- if _, err := io.Copy(rwc, bytes.NewBuffer(s.banner)); err != nil {
- return fmt.Errorf("error sending banner: %w", err)
+ case BannerDownload:
+ if _, err := io.Copy(rwc, bytes.NewBuffer(s.Banner)); err != nil {
+ return fmt.Errorf("error sending Banner: %w", err)
}
case FileDownload:
- s.Stats.DownloadCounter += 1
- s.Stats.DownloadsInProgress += 1
+ s.Stats.Increment(StatDownloadCounter, StatDownloadsInProgress)
defer func() {
- s.Stats.DownloadsInProgress -= 1
+ s.Stats.Decrement(StatDownloadsInProgress)
}()
- var dataOffset int64
- if fileTransfer.fileResumeData != nil {
- dataOffset = int64(binary.BigEndian.Uint32(fileTransfer.fileResumeData.ForkInfoList[0].DataSize[:]))
- }
-
- fw, err := newFileWrapper(s.FS, fullPath, 0)
- if err != nil {
- return err
- }
-
- rLogger.Info("File download started", "filePath", fullPath)
-
- // if file transfer options are included, that means this is a "quick preview" request from a 1.5+ client
- if fileTransfer.options == nil {
- _, err = io.Copy(rwc, fw.ffo)
- if err != nil {
- return err
- }
- }
-
- file, err := fw.dataForkReader()
- if err != nil {
- return err
- }
-
- br := bufio.NewReader(file)
- if _, err := br.Discard(int(dataOffset)); err != nil {
- return err
- }
-
- if _, err = io.Copy(rwc, io.TeeReader(br, fileTransfer.bytesSentCounter)); err != nil {
- return err
- }
-
- // if the client requested to resume transfer, do not send the resource fork header, or it will be appended into the fileWrapper data
- if fileTransfer.fileResumeData == nil {
- err = binary.Write(rwc, binary.BigEndian, fw.rsrcForkHeader())
- if err != nil {
- return err
- }
- }
-
- rFile, err := fw.rsrcForkFile()
+ err = DownloadHandler(rwc, fullPath, fileTransfer, s.FS, rLogger, true)
if err != nil {
- return nil
- }
-
- if _, err = io.Copy(rwc, io.TeeReader(rFile, fileTransfer.bytesSentCounter)); err != nil {
- return err
+ return fmt.Errorf("file download: %w", err)
}
case FileUpload:
- s.Stats.UploadCounter += 1
- s.Stats.UploadsInProgress += 1
- defer func() { s.Stats.UploadsInProgress -= 1 }()
-
- var file *os.File
-
- // A file upload has three possible cases:
- // 1) Upload a new file
- // 2) Resume a partially transferred file
- // 3) Replace a fully uploaded file
- // We have to infer which case applies by inspecting what is already on the filesystem
-
- // 1) Check for existing file:
- _, err = os.Stat(fullPath)
- if err == nil {
- return errors.New("existing file found at " + fullPath)
- }
- if errors.Is(err, fs.ErrNotExist) {
- // If not found, open or create a new .incomplete file
- file, err = os.OpenFile(fullPath+incompleteFileSuffix, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
- if err != nil {
- return err
- }
- }
+ s.Stats.Increment(StatUploadCounter, StatUploadsInProgress)
+ defer func() {
+ s.Stats.Decrement(StatUploadsInProgress)
+ }()
- f, err := newFileWrapper(s.FS, fullPath, 0)
+ err = UploadHandler(rwc, fullPath, fileTransfer, s.FS, rLogger, s.Config.PreserveResourceForks)
if err != nil {
- return err
+ return fmt.Errorf("file upload error: %w", err)
}
- rLogger.Info("File upload started", "dstFile", fullPath)
-
- rForkWriter := io.Discard
- iForkWriter := io.Discard
- if s.Config.PreserveResourceForks {
- rForkWriter, err = f.rsrcForkWriter()
- if err != nil {
- return err
- }
-
- iForkWriter, err = f.infoForkWriter()
- if err != nil {
- return err
- }
- }
-
- if err := receiveFile(rwc, file, rForkWriter, iForkWriter, fileTransfer.bytesSentCounter); err != nil {
- s.Logger.Error(err.Error())
- }
-
- if err := file.Close(); err != nil {
- return err
- }
-
- if err := s.FS.Rename(fullPath+".incomplete", fullPath); err != nil {
- return err
- }
-
- rLogger.Info("File upload complete", "dstFile", fullPath)
-
case FolderDownload:
- s.Stats.DownloadCounter += 1
- s.Stats.DownloadsInProgress += 1
- defer func() { s.Stats.DownloadsInProgress -= 1 }()
-
- // Folder Download flow:
- // 1. Get filePath from the transfer
- // 2. Iterate over files
- // 3. For each fileWrapper:
- // Send fileWrapper header to client
- // The client can reply in 3 ways:
- //
- // 1. If type is an odd number (unknown type?), or fileWrapper download for the current fileWrapper is completed:
- // client sends []byte{0x00, 0x03} to tell the server to continue to the next fileWrapper
- //
- // 2. If download of a fileWrapper is to be resumed:
- // client sends:
- // []byte{0x00, 0x02} // download folder action
- // [2]byte // Resume data size
- // []byte fileWrapper resume data (see myField_FileResumeData)
- //
- // 3. Otherwise, download of the fileWrapper is requested and client sends []byte{0x00, 0x01}
- //
- // When download is requested (case 2 or 3), server replies with:
- // [4]byte - fileWrapper size
- // []byte - Flattened File Object
- //
- // After every fileWrapper download, client could request next fileWrapper with:
- // []byte{0x00, 0x03}
- //
- // This notifies the server to send the next item header
-
- basePathLen := len(fullPath)
-
- rLogger.Info("Start folder download", "path", fullPath)
-
- nextAction := make([]byte, 2)
- if _, err := io.ReadFull(rwc, nextAction); err != nil {
- return err
- }
-
- i := 0
- err = filepath.Walk(fullPath+"/", func(path string, info os.FileInfo, err error) error {
- s.Stats.DownloadCounter += 1
- i += 1
-
- if err != nil {
- return err
- }
-
- // skip dot files
- if strings.HasPrefix(info.Name(), ".") {
- return nil
- }
-
- hlFile, err := newFileWrapper(s.FS, path, 0)
- if err != nil {
- return err
- }
-
- subPath := path[basePathLen+1:]
- rLogger.Debug("Sending fileheader", "i", i, "path", path, "fullFilePath", fullPath, "subPath", subPath, "IsDir", info.IsDir())
-
- if i == 1 {
- return nil
- }
-
- fileHeader := NewFileHeader(subPath, info.IsDir())
- if _, err := io.Copy(rwc, &fileHeader); err != nil {
- return fmt.Errorf("error sending file header: %w", err)
- }
-
- // Read the client's Next Action request
- if _, err := io.ReadFull(rwc, nextAction); err != nil {
- return err
- }
-
- rLogger.Debug("Client folder download action", "action", fmt.Sprintf("%X", nextAction[0:2]))
-
- var dataOffset int64
-
- switch nextAction[1] {
- case dlFldrActionResumeFile:
- // get size of resumeData
- resumeDataByteLen := make([]byte, 2)
- if _, err := io.ReadFull(rwc, resumeDataByteLen); err != nil {
- return err
- }
-
- resumeDataLen := binary.BigEndian.Uint16(resumeDataByteLen)
- resumeDataBytes := make([]byte, resumeDataLen)
- if _, err := io.ReadFull(rwc, resumeDataBytes); err != nil {
- return err
- }
-
- var frd FileResumeData
- if err := frd.UnmarshalBinary(resumeDataBytes); err != nil {
- return err
- }
- dataOffset = int64(binary.BigEndian.Uint32(frd.ForkInfoList[0].DataSize[:]))
- case dlFldrActionNextFile:
- // client asked to skip this file
- return nil
- }
-
- if info.IsDir() {
- return nil
- }
-
- rLogger.Info("File download started",
- "fileName", info.Name(),
- "TransferSize", fmt.Sprintf("%x", hlFile.ffo.TransferSize(dataOffset)),
- )
-
- // Send file size to client
- if _, err := rwc.Write(hlFile.ffo.TransferSize(dataOffset)); err != nil {
- s.Logger.Error(err.Error())
- return err
- }
-
- // Send ffo bytes to client
- _, err = io.Copy(rwc, hlFile.ffo)
- if err != nil {
- return err
- }
-
- file, err := s.FS.Open(path)
- if err != nil {
- return err
- }
-
- // wr := bufio.NewWriterSize(rwc, 1460)
- if _, err = io.Copy(rwc, io.TeeReader(file, fileTransfer.bytesSentCounter)); err != nil {
- return err
- }
-
- if nextAction[1] != 2 && hlFile.ffo.FlatFileHeader.ForkCount[1] == 3 {
- err = binary.Write(rwc, binary.BigEndian, hlFile.rsrcForkHeader())
- if err != nil {
- return err
- }
-
- rFile, err := hlFile.rsrcForkFile()
- if err != nil {
- return err
- }
-
- if _, err = io.Copy(rwc, io.TeeReader(rFile, fileTransfer.bytesSentCounter)); err != nil {
- return err
- }
- }
-
- // Read the client's Next Action request. This is always 3, I think?
- if _, err := io.ReadFull(rwc, nextAction); err != nil {
- return err
- }
-
- return nil
- })
+ s.Stats.Increment(StatDownloadCounter, StatDownloadsInProgress)
+ defer func() {
+ s.Stats.Decrement(StatDownloadsInProgress)
+ }()
+ err = DownloadFolderHandler(rwc, fullPath, fileTransfer, s.FS, rLogger, s.Config.PreserveResourceForks)
if err != nil {
- return err
+ return fmt.Errorf("file upload error: %w", err)
}
case FolderUpload:
- s.Stats.UploadCounter += 1
- s.Stats.UploadsInProgress += 1
- defer func() { s.Stats.UploadsInProgress -= 1 }()
+ s.Stats.Increment(StatUploadCounter, StatUploadsInProgress)
+ defer func() {
+ s.Stats.Decrement(StatUploadsInProgress)
+ }()
+
rLogger.Info(
"Folder upload started",
"dstPath", fullPath,
"FolderItemCount", fileTransfer.FolderItemCount,
)
- // Check if the target folder exists. If not, create it.
- if _, err := s.FS.Stat(fullPath); os.IsNotExist(err) {
- if err := s.FS.Mkdir(fullPath, 0777); err != nil {
- return err
- }
- }
-
- // Begin the folder upload flow by sending the "next file action" to client
- if _, err := rwc.Write([]byte{0, dlFldrActionNextFile}); err != nil {
- return err
- }
-
- fileSize := make([]byte, 4)
-
- for i := 0; i < fileTransfer.ItemCount(); i++ {
- s.Stats.UploadCounter += 1
-
- var fu folderUpload
- if _, err := io.ReadFull(rwc, fu.DataSize[:]); err != nil {
- return err
- }
- if _, err := io.ReadFull(rwc, fu.IsFolder[:]); err != nil {
- return err
- }
- if _, err := io.ReadFull(rwc, fu.PathItemCount[:]); err != nil {
- return err
- }
-
- fu.FileNamePath = make([]byte, binary.BigEndian.Uint16(fu.DataSize[:])-4) // -4 to subtract the path separator bytes
-
- if _, err := io.ReadFull(rwc, fu.FileNamePath); err != nil {
- return err
- }
-
- rLogger.Info(
- "Folder upload continued",
- "FormattedPath", fu.FormattedPath(),
- "IsFolder", fmt.Sprintf("%x", fu.IsFolder),
- "PathItemCount", binary.BigEndian.Uint16(fu.PathItemCount[:]),
- )
-
- if fu.IsFolder == [2]byte{0, 1} {
- if _, err := os.Stat(filepath.Join(fullPath, fu.FormattedPath())); os.IsNotExist(err) {
- if err := os.Mkdir(filepath.Join(fullPath, fu.FormattedPath()), 0777); err != nil {
- return err
- }
- }
-
- // Tell client to send next file
- if _, err := rwc.Write([]byte{0, dlFldrActionNextFile}); err != nil {
- return err
- }
- } else {
- nextAction := dlFldrActionSendFile
-
- // Check if we have the full file already. If so, send dlFldrAction_NextFile to client to skip.
- _, err = os.Stat(filepath.Join(fullPath, fu.FormattedPath()))
- if err != nil && !errors.Is(err, fs.ErrNotExist) {
- return err
- }
- if err == nil {
- nextAction = dlFldrActionNextFile
- }
-
- // Check if we have a partial file already. If so, send dlFldrAction_ResumeFile to client to resume upload.
- incompleteFile, err := os.Stat(filepath.Join(fullPath, fu.FormattedPath()+incompleteFileSuffix))
- if err != nil && !errors.Is(err, fs.ErrNotExist) {
- return err
- }
- if err == nil {
- nextAction = dlFldrActionResumeFile
- }
-
- if _, err := rwc.Write([]byte{0, uint8(nextAction)}); err != nil {
- return err
- }
-
- switch nextAction {
- case dlFldrActionNextFile:
- continue
- case dlFldrActionResumeFile:
- offset := make([]byte, 4)
- binary.BigEndian.PutUint32(offset, uint32(incompleteFile.Size()))
-
- file, err := os.OpenFile(fullPath+"/"+fu.FormattedPath()+incompleteFileSuffix, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
- if err != nil {
- return err
- }
-
- fileResumeData := NewFileResumeData([]ForkInfoList{*NewForkInfoList(offset)})
-
- b, _ := fileResumeData.BinaryMarshal()
-
- bs := make([]byte, 2)
- binary.BigEndian.PutUint16(bs, uint16(len(b)))
-
- if _, err := rwc.Write(append(bs, b...)); err != nil {
- return err
- }
-
- if _, err := io.ReadFull(rwc, fileSize); err != nil {
- return err
- }
-
- if err := receiveFile(rwc, file, io.Discard, io.Discard, fileTransfer.bytesSentCounter); err != nil {
- s.Logger.Error(err.Error())
- }
-
- err = os.Rename(fullPath+"/"+fu.FormattedPath()+".incomplete", fullPath+"/"+fu.FormattedPath())
- if err != nil {
- return err
- }
-
- case dlFldrActionSendFile:
- if _, err := io.ReadFull(rwc, fileSize); err != nil {
- return err
- }
-
- filePath := filepath.Join(fullPath, fu.FormattedPath())
-
- hlFile, err := newFileWrapper(s.FS, filePath, 0)
- if err != nil {
- return err
- }
-
- rLogger.Info("Starting file transfer", "path", filePath, "fileNum", i+1, "fileSize", binary.BigEndian.Uint32(fileSize))
-
- incWriter, err := hlFile.incFileWriter()
- if err != nil {
- return err
- }
-
- rForkWriter := io.Discard
- iForkWriter := io.Discard
- if s.Config.PreserveResourceForks {
- iForkWriter, err = hlFile.infoForkWriter()
- if err != nil {
- return err
- }
-
- rForkWriter, err = hlFile.rsrcForkWriter()
- if err != nil {
- return err
- }
- }
- if err := receiveFile(rwc, incWriter, rForkWriter, iForkWriter, fileTransfer.bytesSentCounter); err != nil {
- return err
- }
-
- if err := os.Rename(filePath+".incomplete", filePath); err != nil {
- return err
- }
- }
-
- // Tell client to send next fileWrapper
- if _, err := rwc.Write([]byte{0, dlFldrActionNextFile}); err != nil {
- return err
- }
- }
+ err = UploadFolderHandler(rwc, fullPath, fileTransfer, s.FS, rLogger, s.Config.PreserveResourceForks)
+ if err != nil {
+ return fmt.Errorf("file upload error: %w", err)
}
- rLogger.Info("Folder upload complete")
}
-
return nil
}
git.r.bdr.sh / rbdr / mobius / blobdiff