daemon.go

   1 /*
   2 goircd -- minimalistic simple Internet Relay Chat (IRC) server
   3 Copyright (C) 2014 Sergey Matveev <stargrave@stargrave.org>
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation, either version 3 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18 package main
  19
  20 import (
  21         "fmt"
  22         "io/ioutil"
  23         "log"
  24         "net"
  25         "regexp"
  26         "sort"
  27         "strings"
  28         "sync"
  29         "time"
  30 )
  31
  32 const (
  33         PingTimeout    = time.Second * 180 // Max time deadline for client's unresponsiveness
  34         PingThreshold  = time.Second * 90  // Max idle client's time before PING are sent
  35         AlivenessCheck = time.Second * 10  // Client's aliveness check period
  36 )
  37
  38 var (
  39         RENickname = regexp.MustCompile("^[a-zA-Z0-9-]{1,9}$")
  40 )
  41
  42 var passwordsRefreshLock sync.Mutex
  43
  44 type Daemon struct {
  45         Verbose            bool
  46         hostname           string
  47         motd               string
  48         clients            map[*Client]bool
  49         clientAliveness    map[*Client]*ClientAlivenessState
  50         rooms              map[string]*Room
  51         roomSinks          map[*Room]chan ClientEvent
  52         lastAlivenessCheck time.Time
  53         logSink            chan<- LogEvent
  54         stateSink          chan<- StateEvent
  55         passwords          map[string]string
  56 }
  57
  58 func NewDaemon(hostname, motd string, logSink chan<- LogEvent, stateSink chan<- StateEvent) *Daemon {
  59         daemon := Daemon{hostname: hostname, motd: motd}
  60         daemon.clients = make(map[*Client]bool)
  61         daemon.clientAliveness = make(map[*Client]*ClientAlivenessState)
  62         daemon.rooms = make(map[string]*Room)
  63         daemon.roomSinks = make(map[*Room]chan ClientEvent)
  64         daemon.logSink = logSink
  65         daemon.stateSink = stateSink
  66         return &daemon
  67 }
  68
  69 func (daemon *Daemon) SendLusers(client *Client) {
  70         lusers := 0
  71         for client := range daemon.clients {
  72                 if client.registered {
  73                         lusers++
  74                 }
  75         }
  76         client.ReplyNicknamed("251", fmt.Sprintf("There are %d users and 0 invisible on 1 servers", lusers))
  77 }
  78
  79 func (daemon *Daemon) SendMotd(client *Client) {
  80         if len(daemon.motd) == 0 {
  81                 client.ReplyNicknamed("422", "MOTD File is missing")
  82                 return
  83         }
  84
  85         motd, err := ioutil.ReadFile(daemon.motd)
  86         if err != nil {
  87                 log.Printf("Can not read motd file %s: %v", daemon.motd, err)
  88                 client.ReplyNicknamed("422", "Error reading MOTD File")
  89                 return
  90         }
  91
  92         client.ReplyNicknamed("375", "- "+daemon.hostname+" Message of the day -")
  93         for _, s := range strings.Split(strings.Trim(string(motd), "\n"), "\n") {
  94                 client.ReplyNicknamed("372", "- "+string(s))
  95         }
  96         client.ReplyNicknamed("376", "End of /MOTD command")
  97 }
  98
  99 func (daemon *Daemon) SendWhois(client *Client, nicknames []string) {
 100         for _, nickname := range nicknames {
 101                 nickname = strings.ToLower(nickname)
 102                 found := false
 103                 for c := range daemon.clients {
 104                         if strings.ToLower(c.nickname) != nickname {
 105                                 continue
 106                         }
 107                         found = true
 108                         h := c.conn.RemoteAddr().String()
 109                         h, _, err := net.SplitHostPort(h)
 110                         if err != nil {
 111                                 log.Printf("Can't parse RemoteAddr %q: %v", h, err)
 112                                 h = "Unknown"
 113                         }
 114                         client.ReplyNicknamed("311", c.nickname, c.username, h, "*", c.realname)
 115                         client.ReplyNicknamed("312", c.nickname, daemon.hostname, daemon.hostname)
 116                         subscriptions := []string{}
 117                         for _, room := range daemon.rooms {
 118                                 for subscriber := range room.members {
 119                                         if subscriber.nickname == nickname {
 120                                                 subscriptions = append(subscriptions, room.name)
 121                                         }
 122                                 }
 123                         }
 124                         sort.Strings(subscriptions)
 125                         client.ReplyNicknamed("319", c.nickname, strings.Join(subscriptions, " "))
 126                         client.ReplyNicknamed("318", c.nickname, "End of /WHOIS list")
 127                 }
 128                 if !found {
 129                         client.ReplyNoNickChan(nickname)
 130                 }
 131         }
 132 }
 133
 134 func (daemon *Daemon) SendList(client *Client, cols []string) {
 135         var rooms []string
 136         if (len(cols) > 1) && (cols[1] != "") {
 137                 rooms = strings.Split(strings.Split(cols[1], " ")[0], ",")
 138         } else {
 139                 rooms = []string{}
 140                 for room := range daemon.rooms {
 141                         rooms = append(rooms, room)
 142                 }
 143         }
 144         sort.Strings(rooms)
 145         for _, room := range rooms {
 146                 r, found := daemon.rooms[room]
 147                 if found {
 148                         client.ReplyNicknamed("322", room, fmt.Sprintf("%d", len(r.members)), r.topic)
 149                 }
 150         }
 151         client.ReplyNicknamed("323", "End of /LIST")
 152 }
 153
 154 // Unregistered client workflow processor. Unregistered client:
 155 // * is not PINGed
 156 // * only QUIT, NICK and USER commands are processed
 157 // * other commands are quietly ignored
 158 // When client finishes NICK/USER workflow, then MOTD and LUSERS are send to him.
 159 func (daemon *Daemon) ClientRegister(client *Client, command string, cols []string) {
 160         switch command {
 161         case "PASS":
 162                 if len(cols) == 1 || len(cols[1]) < 1 {
 163                         client.ReplyNotEnoughParameters("PASS")
 164                         return
 165                 }
 166                 client.password = cols[1]
 167         case "NICK":
 168                 if len(cols) == 1 || len(cols[1]) < 1 {
 169                         client.ReplyParts("431", "No nickname given")
 170                         return
 171                 }
 172                 nickname := cols[1]
 173                 for existingClient := range daemon.clients {
 174                         if existingClient.nickname == nickname {
 175                                 client.ReplyParts("433", "*", nickname, "Nickname is already in use")
 176                                 return
 177                         }
 178                 }
 179                 if !RENickname.MatchString(nickname) {
 180                         client.ReplyParts("432", "*", cols[1], "Erroneous nickname")
 181                         return
 182                 }
 183                 client.nickname = nickname
 184         case "USER":
 185                 if len(cols) == 1 {
 186                         client.ReplyNotEnoughParameters("USER")
 187                         return
 188                 }
 189                 args := strings.SplitN(cols[1], " ", 4)
 190                 if len(args) < 4 {
 191                         client.ReplyNotEnoughParameters("USER")
 192                         return
 193                 }
 194                 client.username = args[0]
 195                 client.realname = strings.TrimLeft(args[3], ":")
 196         }
 197         if client.nickname != "*" && client.username != "" {
 198                 passwordsRefreshLock.Lock()
 199                 if daemon.passwords != nil && (client.password == "" || daemon.passwords[client.nickname] != client.password) {
 200                         passwordsRefreshLock.Unlock()
 201                         client.ReplyParts("462", "You may not register")
 202                         client.conn.Close()
 203                         return
 204                 }
 205                 passwordsRefreshLock.Unlock()
 206                 client.registered = true
 207                 client.ReplyNicknamed("001", "Hi, welcome to IRC")
 208                 client.ReplyNicknamed("002", "Your host is "+daemon.hostname+", running goircd")
 209                 client.ReplyNicknamed("003", "This server was created sometime")
 210                 client.ReplyNicknamed("004", daemon.hostname+" goircd o o")
 211                 daemon.SendLusers(client)
 212                 daemon.SendMotd(client)
 213                 log.Println(client, "logged in")
 214         }
 215 }
 216
 217 // Register new room in Daemon. Create an object, events sink, save pointers
 218 // to corresponding daemon's places and start room's processor goroutine.
 219 func (daemon *Daemon) RoomRegister(name string) (*Room, chan<- ClientEvent) {
 220         roomNew := NewRoom(daemon.hostname, name, daemon.logSink, daemon.stateSink)
 221         roomNew.Verbose = daemon.Verbose
 222         roomSink := make(chan ClientEvent)
 223         daemon.rooms[name] = roomNew
 224         daemon.roomSinks[roomNew] = roomSink
 225         go roomNew.Processor(roomSink)
 226         return roomNew, roomSink
 227 }
 228
 229 func (daemon *Daemon) HandlerJoin(client *Client, cmd string) {
 230         args := strings.Split(cmd, " ")
 231         rooms := strings.Split(args[0], ",")
 232         var keys []string
 233         if len(args) > 1 {
 234                 keys = strings.Split(args[1], ",")
 235         } else {
 236                 keys = []string{}
 237         }
 238         for n, room := range rooms {
 239                 if !RoomNameValid(room) {
 240                         client.ReplyNoChannel(room)
 241                         continue
 242                 }
 243                 var key string
 244                 if (n < len(keys)) && (keys[n] != "") {
 245                         key = keys[n]
 246                 } else {
 247                         key = ""
 248                 }
 249                 denied := false
 250                 joined := false
 251                 for roomExisting, roomSink := range daemon.roomSinks {
 252                         if room == roomExisting.name {
 253                                 if (roomExisting.key != "") && (roomExisting.key != key) {
 254                                         denied = true
 255                                 } else {
 256                                         roomSink <- ClientEvent{client, EventNew, ""}
 257                                         joined = true
 258                                 }
 259                                 break
 260                         }
 261                 }
 262                 if denied {
 263                         client.ReplyNicknamed("475", room, "Cannot join channel (+k) - bad key")
 264                 }
 265                 if denied || joined {
 266                         continue
 267                 }
 268                 roomNew, roomSink := daemon.RoomRegister(room)
 269                 log.Println("Room", roomNew, "created")
 270                 if key != "" {
 271                         roomNew.key = key
 272                         roomNew.StateSave()
 273                 }
 274                 roomSink <- ClientEvent{client, EventNew, ""}
 275         }
 276 }
 277
 278 func (daemon *Daemon) Processor(events <-chan ClientEvent) {
 279         for event := range events {
 280                 now := time.Now()
 281                 client := event.client
 282
 283                 // Check for clients aliveness
 284                 if daemon.lastAlivenessCheck.Add(AlivenessCheck).Before(now) {
 285                         for c := range daemon.clients {
 286                                 aliveness, alive := daemon.clientAliveness[c]
 287                                 if !alive {
 288                                         continue
 289                                 }
 290                                 if aliveness.timestamp.Add(PingTimeout).Before(now) {
 291                                         log.Println(c, "ping timeout")
 292                                         c.conn.Close()
 293                                         continue
 294                                 }
 295                                 if !aliveness.pingSent && aliveness.timestamp.Add(PingThreshold).Before(now) {
 296                                         if c.registered {
 297                                                 c.Msg("PING :" + daemon.hostname)
 298                                                 aliveness.pingSent = true
 299                                         } else {
 300                                                 log.Println(c, "ping timeout")
 301                                                 c.conn.Close()
 302                                         }
 303                                 }
 304                         }
 305                         daemon.lastAlivenessCheck = now
 306                 }
 307
 308                 switch event.eventType {
 309                 case EventNew:
 310                         daemon.clients[client] = true
 311                         daemon.clientAliveness[client] = &ClientAlivenessState{pingSent: false, timestamp: now}
 312                 case EventDel:
 313                         delete(daemon.clients, client)
 314                         delete(daemon.clientAliveness, client)
 315                         for _, roomSink := range daemon.roomSinks {
 316                                 roomSink <- event
 317                         }
 318                 case EventMsg:
 319                         cols := strings.SplitN(event.text, " ", 2)
 320                         command := strings.ToUpper(cols[0])
 321                         if daemon.Verbose {
 322                                 log.Println(client, "command", command)
 323                         }
 324                         if command == "QUIT" {
 325                                 log.Println(client, "quit")
 326                                 delete(daemon.clients, client)
 327                                 delete(daemon.clientAliveness, client)
 328                                 client.conn.Close()
 329                                 continue
 330                         }
 331                         if !client.registered {
 332                                 daemon.ClientRegister(client, command, cols)
 333                                 continue
 334                         }
 335                         switch command {
 336                         case "AWAY":
 337                                 continue
 338                         case "JOIN":
 339                                 if len(cols) == 1 || len(cols[1]) < 1 {
 340                                         client.ReplyNotEnoughParameters("JOIN")
 341                                         continue
 342                                 }
 343                                 daemon.HandlerJoin(client, cols[1])
 344                         case "LIST":
 345                                 daemon.SendList(client, cols)
 346                         case "LUSERS":
 347                                 daemon.SendLusers(client)
 348                         case "MODE":
 349                                 if len(cols) == 1 || len(cols[1]) < 1 {
 350                                         client.ReplyNotEnoughParameters("MODE")
 351                                         continue
 352                                 }
 353                                 cols = strings.SplitN(cols[1], " ", 2)
 354                                 if cols[0] == client.username {
 355                                         if len(cols) == 1 {
 356                                                 client.Msg("221 " + client.nickname + " +")
 357                                         } else {
 358                                                 client.ReplyNicknamed("501", "Unknown MODE flag")
 359                                         }
 360                                         continue
 361                                 }
 362                                 room := cols[0]
 363                                 r, found := daemon.rooms[room]
 364                                 if !found {
 365                                         client.ReplyNoChannel(room)
 366                                         continue
 367                                 }
 368                                 if len(cols) == 1 {
 369                                         daemon.roomSinks[r] <- ClientEvent{client, EventMode, ""}
 370                                 } else {
 371                                         daemon.roomSinks[r] <- ClientEvent{client, EventMode, cols[1]}
 372                                 }
 373                         case "MOTD":
 374                                 go daemon.SendMotd(client)
 375                         case "PART":
 376                                 if len(cols) == 1 || len(cols[1]) < 1 {
 377                                         client.ReplyNotEnoughParameters("PART")
 378                                         continue
 379                                 }
 380                                 for _, room := range strings.Split(cols[1], ",") {
 381                                         r, found := daemon.rooms[room]
 382                                         if !found {
 383                                                 client.ReplyNoChannel(room)
 384                                                 continue
 385                                         }
 386                                         daemon.roomSinks[r] <- ClientEvent{client, EventDel, ""}
 387                                 }
 388                         case "PING":
 389                                 if len(cols) == 1 {
 390                                         client.ReplyNicknamed("409", "No origin specified")
 391                                         continue
 392                                 }
 393                                 client.Reply(fmt.Sprintf("PONG %s :%s", daemon.hostname, cols[1]))
 394                         case "PONG":
 395                                 continue
 396                         case "NOTICE", "PRIVMSG":
 397                                 if len(cols) == 1 {
 398                                         client.ReplyNicknamed("411", "No recipient given ("+command+")")
 399                                         continue
 400                                 }
 401                                 cols = strings.SplitN(cols[1], " ", 2)
 402                                 if len(cols) == 1 {
 403                                         client.ReplyNicknamed("412", "No text to send")
 404                                         continue
 405                                 }
 406                                 msg := ""
 407                                 target := strings.ToLower(cols[0])
 408                                 for c := range daemon.clients {
 409                                         if c.nickname == target {
 410                                                 msg = fmt.Sprintf(":%s %s %s %s", client, command, c.nickname, cols[1])
 411                                                 c.Msg(msg)
 412                                                 break
 413                                         }
 414                                 }
 415                                 if msg != "" {
 416                                         continue
 417                                 }
 418                                 r, found := daemon.rooms[target]
 419                                 if !found {
 420                                         client.ReplyNoNickChan(target)
 421                                 }
 422                                 daemon.roomSinks[r] <- ClientEvent{client, EventMsg, command + " " + strings.TrimLeft(cols[1], ":")}
 423                         case "TOPIC":
 424                                 if len(cols) == 1 {
 425                                         client.ReplyNotEnoughParameters("TOPIC")
 426                                         continue
 427                                 }
 428                                 cols = strings.SplitN(cols[1], " ", 2)
 429                                 r, found := daemon.rooms[cols[0]]
 430                                 if !found {
 431                                         client.ReplyNoChannel(cols[0])
 432                                         continue
 433                                 }
 434                                 var change string
 435                                 if len(cols) > 1 {
 436                                         change = cols[1]
 437                                 } else {
 438                                         change = ""
 439                                 }
 440                                 daemon.roomSinks[r] <- ClientEvent{client, EventTopic, change}
 441                         case "WHO":
 442                                 if len(cols) == 1 || len(cols[1]) < 1 {
 443                                         client.ReplyNotEnoughParameters("WHO")
 444                                         continue
 445                                 }
 446                                 room := strings.Split(cols[1], " ")[0]
 447                                 r, found := daemon.rooms[room]
 448                                 if !found {
 449                                         client.ReplyNoChannel(room)
 450                                         continue
 451                                 }
 452                                 daemon.roomSinks[r] <- ClientEvent{client, EventWho, ""}
 453                         case "WHOIS":
 454                                 if len(cols) == 1 || len(cols[1]) < 1 {
 455                                         client.ReplyNotEnoughParameters("WHOIS")
 456                                         continue
 457                                 }
 458                                 cols := strings.Split(cols[1], " ")
 459                                 nicknames := strings.Split(cols[len(cols)-1], ",")
 460                                 daemon.SendWhois(client, nicknames)
 461                         default:
 462                                 client.ReplyNicknamed("421", command, "Unknown command")
 463                         }
 464                 }
 465                 if aliveness, alive := daemon.clientAliveness[client]; alive {
 466                         aliveness.timestamp = now
 467                         aliveness.pingSent = false
 468                 }
 469         }
 470 }
 471
 472 func (daemon *Daemon) PasswordsRefresh() {
 473         contents, err := ioutil.ReadFile(*passwords)
 474         if err != nil {
 475                 log.Fatalf("Can no read passwords file %s: %s", *passwords, err)
 476                 return
 477         }
 478         processed := make(map[string]string)
 479         for _, entry := range strings.Split(string(contents), "\n") {
 480                 loginAndPassword := strings.Split(entry, ":")
 481                 if len(loginAndPassword) == 2 {
 482                         processed[loginAndPassword[0]] = loginAndPassword[1]
 483                 }
 484         }
 485         log.Printf("Read %d passwords", len(processed))
 486         passwordsRefreshLock.Lock()
 487         daemon.passwords = processed
 488         passwordsRefreshLock.Unlock()
 489 }