daemon.go

   1 /*
   2 goircd -- minimalistic simple Internet Relay Chat (IRC) server
   3 Copyright (C) 2014-2020 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, version 3 of the License.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  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         // Max deadline time of client's unresponsiveness
  34         PingTimeout = time.Second * 180
  35         // Max idle client's time before PING are sent
  36         PingThreshold = time.Second * 90
  37 )
  38
  39 var (
  40         RENickname = regexp.MustCompile("^[a-zA-Z0-9-]{1,24}$")
  41
  42         clients    map[*Client]struct{} = make(map[*Client]struct{})
  43         clientsM   sync.RWMutex
  44         rooms      map[string]*Room = make(map[string]*Room)
  45         roomsM     sync.RWMutex
  46         roomsGroup sync.WaitGroup
  47         roomSinks  map[*Room]chan ClientEvent = make(map[*Room]chan ClientEvent)
  48 )
  49
  50 func SendLusers(client *Client) {
  51         lusers := 0
  52         clientsM.RLock()
  53         for client := range clients {
  54                 if client.registered {
  55                         lusers++
  56                 }
  57         }
  58         clientsM.RUnlock()
  59         client.ReplyNicknamed("251", fmt.Sprintf("There are %d users and 0 invisible on 1 servers", lusers))
  60 }
  61
  62 func SendMotd(client *Client) {
  63         if motd == nil {
  64                 client.ReplyNicknamed("422", "MOTD File is missing")
  65                 return
  66         }
  67         motdText, err := ioutil.ReadFile(*motd)
  68         if err != nil {
  69                 log.Printf("Can not read motd file %s: %v", *motd, err)
  70                 client.ReplyNicknamed("422", "Error reading MOTD File")
  71                 return
  72         }
  73         client.ReplyNicknamed("375", "- "+*hostname+" Message of the day -")
  74         for _, s := range strings.Split(strings.TrimSuffix(string(motdText), "\n"), "\n") {
  75                 client.ReplyNicknamed("372", "- "+s)
  76         }
  77         client.ReplyNicknamed("376", "End of /MOTD command")
  78 }
  79
  80 func SendWhois(client *Client, nicknames []string) {
  81         var c *Client
  82         var hostPort string
  83         var err error
  84         var subscriptions []string
  85         var room *Room
  86         var subscriber *Client
  87         for _, nickname := range nicknames {
  88                 nickname = strings.ToLower(nickname)
  89                 clientsM.RLock()
  90                 for c = range clients {
  91                         if strings.ToLower(*c.nickname) == nickname {
  92                                 clientsM.RUnlock()
  93                                 goto Found
  94                         }
  95                 }
  96                 clientsM.RUnlock()
  97                 client.ReplyNoNickChan(nickname)
  98                 continue
  99         Found:
 100                 hostPort, _, err = net.SplitHostPort(c.conn.RemoteAddr().String())
 101                 if err != nil {
 102                         log.Printf("Can't parse RemoteAddr %q: %v", hostPort, err)
 103                         hostPort = "Unknown"
 104                 }
 105                 client.ReplyNicknamed("311", *c.nickname, *c.username, hostPort, "*", *c.realname)
 106                 client.ReplyNicknamed("312", *c.nickname, *hostname, *hostname)
 107                 if c.away != nil {
 108                         client.ReplyNicknamed("301", *c.nickname, *c.away)
 109                 }
 110                 subscriptions = make([]string, 0)
 111                 roomsM.RLock()
 112                 for _, room = range rooms {
 113                         for subscriber = range room.members {
 114                                 if *subscriber.nickname == nickname {
 115                                         subscriptions = append(subscriptions, *room.name)
 116                                 }
 117                         }
 118                 }
 119                 roomsM.RUnlock()
 120                 sort.Strings(subscriptions)
 121                 client.ReplyNicknamed("319", *c.nickname, strings.Join(subscriptions, " "))
 122                 client.ReplyNicknamed("318", *c.nickname, "End of /WHOIS list")
 123         }
 124 }
 125
 126 func SendList(client *Client, cols []string) {
 127         var rs []string
 128         var r string
 129         if (len(cols) > 1) && (cols[1] != "") {
 130                 rs = strings.Split(strings.Split(cols[1], " ")[0], ",")
 131         } else {
 132                 rs = make([]string, 0)
 133                 roomsM.RLock()
 134                 for r = range rooms {
 135                         rs = append(rs, r)
 136                 }
 137                 roomsM.RUnlock()
 138         }
 139         sort.Strings(rs)
 140         var room *Room
 141         var found bool
 142         for _, r = range rs {
 143                 roomsM.RLock()
 144                 if room, found = rooms[r]; found {
 145                         client.ReplyNicknamed(
 146                                 "322",
 147                                 r,
 148                                 fmt.Sprintf("%d", len(room.members)),
 149                                 *room.topic,
 150                         )
 151                 }
 152                 roomsM.RUnlock()
 153         }
 154         client.ReplyNicknamed("323", "End of /LIST")
 155 }
 156
 157 // Unregistered client workflow processor. Unregistered client:
 158 // * is not PINGed
 159 // * only QUIT, NICK and USER commands are processed
 160 // * other commands are quietly ignored
 161 // When client finishes NICK/USER workflow, then MOTD and LUSERS are send to him.
 162 func ClientRegister(client *Client, cmd string, cols []string) {
 163         switch cmd {
 164         case "PASS":
 165                 if len(cols) == 1 || len(cols[1]) < 1 {
 166                         client.ReplyNotEnoughParameters("PASS")
 167                         return
 168                 }
 169                 password := strings.TrimPrefix(cols[1], ":")
 170                 client.password = &password
 171         case "NICK":
 172                 if len(cols) == 1 || len(cols[1]) < 1 {
 173                         client.ReplyParts("431", "No nickname given")
 174                         return
 175                 }
 176                 nickname := cols[1]
 177                 // Compatibility with some clients prepending colons to nickname
 178                 nickname = strings.TrimPrefix(nickname, ":")
 179                 nickname = strings.ToLower(nickname)
 180                 clientsM.RLock()
 181                 for existingClient := range clients {
 182                         if *existingClient.nickname == nickname {
 183                                 clientsM.RUnlock()
 184                                 client.ReplyParts("433", "*", nickname, "Nickname is already in use")
 185                                 return
 186                         }
 187                 }
 188                 clientsM.RUnlock()
 189                 if !RENickname.MatchString(nickname) {
 190                         client.ReplyParts("432", "*", cols[1], "Erroneous nickname")
 191                         return
 192                 }
 193                 client.nickname = &nickname
 194         case "USER":
 195                 if len(cols) == 1 {
 196                         client.ReplyNotEnoughParameters("USER")
 197                         return
 198                 }
 199                 args := strings.SplitN(cols[1], " ", 4)
 200                 if len(args) < 4 {
 201                         client.ReplyNotEnoughParameters("USER")
 202                         return
 203                 }
 204                 client.username = &args[0]
 205                 realname := strings.TrimLeft(args[3], ":")
 206                 client.realname = &realname
 207         }
 208         if *client.nickname != "*" && *client.username != "" {
 209                 if passwords != nil && *passwords != "" {
 210                         if client.password == nil {
 211                                 client.ReplyParts("462", "You may not register")
 212                                 client.Close()
 213                                 return
 214                         }
 215                         contents, err := ioutil.ReadFile(*passwords)
 216                         if err != nil {
 217                                 log.Fatalf("Can no read passwords file %s: %s", *passwords, err)
 218                                 return
 219                         }
 220                         for _, entry := range strings.Split(string(contents), "\n") {
 221                                 if entry == "" {
 222                                         continue
 223                                 }
 224                                 if lp := strings.Split(entry, ":"); lp[0] == *client.nickname && lp[1] != *client.password {
 225                                         client.ReplyParts("462", "You may not register")
 226                                         client.Close()
 227                                         return
 228                                 }
 229                         }
 230                 }
 231                 client.registered = true
 232                 client.ReplyNicknamed("001", "Hi, welcome to IRC")
 233                 client.ReplyNicknamed("002", "Your host is "+*hostname+", running goircd "+version)
 234                 client.ReplyNicknamed("003", "This server was created sometime")
 235                 client.ReplyNicknamed("004", *hostname+" goircd o o")
 236                 SendLusers(client)
 237                 SendMotd(client)
 238                 log.Println(client, "logged in")
 239         }
 240 }
 241
 242 // Register new room in Daemon. Create an object, events sink, save pointers
 243 // to corresponding daemon's places and start room's processor goroutine.
 244 func RoomRegister(name string) (*Room, chan ClientEvent) {
 245         roomNew := NewRoom(name)
 246         roomSink := make(chan ClientEvent)
 247         roomsM.Lock()
 248         rooms[name] = roomNew
 249         roomSinks[roomNew] = roomSink
 250         roomsM.Unlock()
 251         go roomNew.Processor(roomSink)
 252         roomsGroup.Add(1)
 253         return roomNew, roomSink
 254 }
 255
 256 func HandlerJoin(client *Client, cmd string) {
 257         args := strings.Split(cmd, " ")
 258         rs := strings.Split(args[0], ",")
 259         var keys []string
 260         if len(args) > 1 {
 261                 keys = strings.Split(args[1], ",")
 262         } else {
 263                 keys = make([]string, 0)
 264         }
 265         var roomExisting *Room
 266         var roomSink chan ClientEvent
 267         var roomNew *Room
 268         for n, room := range rs {
 269                 if !RoomNameValid(room) {
 270                         client.ReplyNoChannel(room)
 271                         continue
 272                 }
 273                 var key string
 274                 if (n < len(keys)) && (keys[n] != "") {
 275                         key = keys[n]
 276                 } else {
 277                         key = ""
 278                 }
 279                 roomsM.RLock()
 280                 for roomExisting, roomSink = range roomSinks {
 281                         if room == *roomExisting.name {
 282                                 roomsM.RUnlock()
 283                                 if (*roomExisting.key != "") && (*roomExisting.key != key) {
 284                                         goto Denied
 285                                 }
 286                                 roomSink <- ClientEvent{client, EventNew, ""}
 287                                 goto Joined
 288                         }
 289                 }
 290                 roomsM.RUnlock()
 291                 roomNew, roomSink = RoomRegister(room)
 292                 log.Println("Room", roomNew, "created")
 293                 if key != "" {
 294                         roomNew.key = &key
 295                         roomNew.StateSave()
 296                 }
 297                 roomSink <- ClientEvent{client, EventNew, ""}
 298                 continue
 299         Denied:
 300                 client.ReplyNicknamed("475", room, "Cannot join channel (+k) - bad key")
 301         Joined:
 302         }
 303 }
 304
 305 func Processor(events chan ClientEvent, finished chan struct{}) {
 306         var now time.Time
 307         go func() {
 308                 for {
 309                         time.Sleep(10 * time.Second)
 310                         events <- ClientEvent{eventType: EventTick}
 311                 }
 312         }()
 313         for event := range events {
 314                 now = time.Now()
 315                 client := event.client
 316                 switch event.eventType {
 317                 case EventTick:
 318                         clientsM.RLock()
 319                         for c := range clients {
 320                                 if c.recvTimestamp.Add(PingTimeout).Before(now) {
 321                                         log.Println(c, "ping timeout")
 322                                         c.Close()
 323                                         continue
 324                                 }
 325                                 if c.sendTimestamp.Add(PingThreshold).Before(now) {
 326                                         if c.registered {
 327                                                 c.Msg("PING :" + *hostname)
 328                                                 c.sendTimestamp = time.Now()
 329                                         } else {
 330                                                 log.Println(c, "ping timeout")
 331                                                 c.Close()
 332                                         }
 333                                 }
 334                         }
 335                         clientsM.RUnlock()
 336                         roomsM.Lock()
 337                         for rn, r := range rooms {
 338                                 if *statedir == "" && len(r.members) == 0 {
 339                                         log.Println(rn, "emptied room")
 340                                         delete(rooms, rn)
 341                                         close(roomSinks[r])
 342                                         delete(roomSinks, r)
 343                                 }
 344                         }
 345                         roomsM.Unlock()
 346                 case EventTerm:
 347                         roomsM.RLock()
 348                         for _, sink := range roomSinks {
 349                                 sink <- ClientEvent{eventType: EventTerm}
 350                         }
 351                         roomsM.RUnlock()
 352                         roomsGroup.Wait()
 353                         close(finished)
 354                         return
 355                 case EventNew:
 356                         clientsM.Lock()
 357                         clients[client] = struct{}{}
 358                         clientsM.Unlock()
 359                 case EventDel:
 360                         clientsM.Lock()
 361                         delete(clients, client)
 362                         clientsM.Unlock()
 363                         roomsM.RLock()
 364                         for _, roomSink := range roomSinks {
 365                                 roomSink <- event
 366                         }
 367                         roomsM.RUnlock()
 368                 case EventMsg:
 369                         cols := strings.SplitN(event.text, " ", 2)
 370                         cmd := strings.ToUpper(cols[0])
 371                         if *verbose {
 372                                 log.Println(client, "command", cmd)
 373                         }
 374                         if cmd == "QUIT" {
 375                                 log.Println(client, "quit")
 376                                 client.Close()
 377                                 continue
 378                         }
 379                         if !client.registered {
 380                                 ClientRegister(client, cmd, cols)
 381                                 continue
 382                         }
 383                         if client != nil {
 384                                 client.recvTimestamp = now
 385                         }
 386                         switch cmd {
 387                         case "AWAY":
 388                                 if len(cols) == 1 {
 389                                         client.away = nil
 390                                         client.ReplyNicknamed("305", "You are no longer marked as being away")
 391                                         continue
 392                                 }
 393                                 msg := strings.TrimLeft(cols[1], ":")
 394                                 client.away = &msg
 395                                 client.ReplyNicknamed("306", "You have been marked as being away")
 396                         case "JOIN":
 397                                 if len(cols) == 1 || len(cols[1]) < 1 {
 398                                         client.ReplyNotEnoughParameters("JOIN")
 399                                         continue
 400                                 }
 401                                 HandlerJoin(client, cols[1])
 402                         case "LIST":
 403                                 SendList(client, cols)
 404                         case "LUSERS":
 405                                 SendLusers(client)
 406                         case "MODE":
 407                                 if len(cols) == 1 || len(cols[1]) < 1 {
 408                                         client.ReplyNotEnoughParameters("MODE")
 409                                         continue
 410                                 }
 411                                 cols = strings.SplitN(cols[1], " ", 2)
 412                                 if cols[0] == *client.username {
 413                                         if len(cols) == 1 {
 414                                                 client.Msg("221 " + *client.nickname + " +")
 415                                         } else {
 416                                                 client.ReplyNicknamed("501", "Unknown MODE flag")
 417                                         }
 418                                         continue
 419                                 }
 420                                 room := cols[0]
 421                                 roomsM.RLock()
 422                                 r, found := rooms[room]
 423                                 if !found {
 424                                         client.ReplyNoChannel(room)
 425                                         roomsM.RUnlock()
 426                                         continue
 427                                 }
 428                                 if len(cols) == 1 {
 429                                         roomSinks[r] <- ClientEvent{client, EventMode, ""}
 430                                 } else {
 431                                         roomSinks[r] <- ClientEvent{client, EventMode, cols[1]}
 432                                 }
 433                                 roomsM.RUnlock()
 434                         case "MOTD":
 435                                 SendMotd(client)
 436                         case "PART":
 437                                 if len(cols) == 1 || len(cols[1]) < 1 {
 438                                         client.ReplyNotEnoughParameters("PART")
 439                                         continue
 440                                 }
 441                                 rs := strings.Split(cols[1], " ")[0]
 442                                 roomsM.RLock()
 443                                 for _, room := range strings.Split(rs, ",") {
 444                                         if r, found := rooms[room]; found {
 445                                                 roomSinks[r] <- ClientEvent{client, EventDel, ""}
 446                                         } else {
 447                                                 client.ReplyNoChannel(room)
 448                                         }
 449                                 }
 450                                 roomsM.RUnlock()
 451                         case "PING":
 452                                 if len(cols) == 1 {
 453                                         client.ReplyNicknamed("409", "No origin specified")
 454                                         continue
 455                                 }
 456                                 client.Reply(fmt.Sprintf("PONG %s :%s", *hostname, cols[1]))
 457                         case "PONG":
 458                                 continue
 459                         case "NOTICE", "PRIVMSG":
 460                                 if len(cols) == 1 {
 461                                         client.ReplyNicknamed("411", "No recipient given ("+cmd+")")
 462                                         continue
 463                                 }
 464                                 cols = strings.SplitN(cols[1], " ", 2)
 465                                 if len(cols) == 1 {
 466                                         client.ReplyNicknamed("412", "No text to send")
 467                                         continue
 468                                 }
 469                                 msg := ""
 470                                 target := strings.ToLower(cols[0])
 471                                 clientsM.RLock()
 472                                 for c := range clients {
 473                                         if *c.nickname == target {
 474                                                 msg = fmt.Sprintf(":%s %s %s %s", client, cmd, *c.nickname, cols[1])
 475                                                 c.Msg(msg)
 476                                                 if c.away != nil {
 477                                                         client.ReplyNicknamed("301", *c.nickname, *c.away)
 478                                                 }
 479                                                 break
 480                                         }
 481                                 }
 482                                 clientsM.RUnlock()
 483                                 if msg != "" {
 484                                         continue
 485                                 }
 486                                 roomsM.RLock()
 487                                 if r, found := rooms[target]; found {
 488                                         roomSinks[r] <- ClientEvent{
 489                                                 client,
 490                                                 EventMsg,
 491                                                 cmd + " " + strings.TrimLeft(cols[1], ":"),
 492                                         }
 493                                 } else {
 494                                         client.ReplyNoNickChan(target)
 495                                 }
 496                                 roomsM.RUnlock()
 497                         case "TOPIC":
 498                                 if len(cols) == 1 {
 499                                         client.ReplyNotEnoughParameters("TOPIC")
 500                                         continue
 501                                 }
 502                                 cols = strings.SplitN(cols[1], " ", 2)
 503                                 roomsM.RLock()
 504                                 r, found := rooms[cols[0]]
 505                                 roomsM.RUnlock()
 506                                 if !found {
 507                                         client.ReplyNoChannel(cols[0])
 508                                         continue
 509                                 }
 510                                 var change string
 511                                 if len(cols) > 1 {
 512                                         change = cols[1]
 513                                 } else {
 514                                         change = ""
 515                                 }
 516                                 roomsM.RLock()
 517                                 roomSinks[r] <- ClientEvent{client, EventTopic, change}
 518                                 roomsM.RUnlock()
 519                         case "WHO":
 520                                 if len(cols) == 1 || len(cols[1]) < 1 {
 521                                         client.ReplyNotEnoughParameters("WHO")
 522                                         continue
 523                                 }
 524                                 room := strings.Split(cols[1], " ")[0]
 525                                 roomsM.RLock()
 526                                 if r, found := rooms[room]; found {
 527                                         roomSinks[r] <- ClientEvent{client, EventWho, ""}
 528                                 } else {
 529                                         client.ReplyNoChannel(room)
 530                                 }
 531                                 roomsM.RUnlock()
 532                         case "WHOIS":
 533                                 if len(cols) == 1 || len(cols[1]) < 1 {
 534                                         client.ReplyNotEnoughParameters("WHOIS")
 535                                         continue
 536                                 }
 537                                 cols := strings.Split(cols[1], " ")
 538                                 nicknames := strings.Split(cols[len(cols)-1], ",")
 539                                 SendWhois(client, nicknames)
 540                         case "ISON":
 541                                 if len(cols) == 1 || len(cols[1]) < 1 {
 542                                         client.ReplyNotEnoughParameters("ISON")
 543                                         continue
 544                                 }
 545                                 nicksKnown := make(map[string]struct{})
 546                                 clientsM.RLock()
 547                                 for c := range clients {
 548                                         nicksKnown[*c.nickname] = struct{}{}
 549                                 }
 550                                 clientsM.RUnlock()
 551                                 var nicksExists []string
 552                                 for _, nickname := range strings.Split(cols[1], " ") {
 553                                         if _, exists := nicksKnown[nickname]; exists {
 554                                                 nicksExists = append(nicksExists, nickname)
 555                                         }
 556                                 }
 557                                 client.ReplyNicknamed("303", strings.Join(nicksExists, " "))
 558                         case "VERSION":
 559                                 var debug string
 560                                 if *verbose {
 561                                         debug = "debug"
 562                                 } else {
 563                                         debug = ""
 564                                 }
 565                                 client.ReplyNicknamed("351", fmt.Sprintf("%s.%s %s :", version, debug, *hostname))
 566                         default:
 567                                 client.ReplyNicknamed("421", cmd, "Unknown command")
 568                         }
 569                 }
 570         }
 571 }