src/modules/m_spanningtree/utils.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include "commands/cmd_whois.h"
  16 #include "commands/cmd_stats.h"
  17 #include "socket.h"
  18 #include "xline.h"
  19 #include "transport.h"
  20 #include "socketengine.h"
  21
  22 #include "m_spanningtree/main.h"
  23 #include "m_spanningtree/utils.h"
  24 #include "m_spanningtree/treeserver.h"
  25 #include "m_spanningtree/link.h"
  26 #include "m_spanningtree/treesocket.h"
  27 #include "m_spanningtree/resolvers.h"
  28
  29 /* $ModDep: m_spanningtree/resolvers.h m_spanningtree/main.h m_spanningtree/utils.h m_spanningtree/treeserver.h m_spanningtree/link.h m_spanningtree/treesocket.h */
  30
  31 /* Create server sockets off a listener. */
  32 void ServerSocketListener::OnAcceptReady(const std::string &ipconnectedto, int newsock, const std::string &incomingip)
  33 {
  34         bool found = false;
  35         char *ip = (char *)incomingip.c_str(); // XXX ugly cast
  36
  37         found = (std::find(Utils->ValidIPs.begin(), Utils->ValidIPs.end(), ip) != Utils->ValidIPs.end());
  38         if (!found)
  39         {
  40                 for (std::vector<std::string>::iterator i = Utils->ValidIPs.begin(); i != Utils->ValidIPs.end(); i++)
  41                 {
  42                         if (*i == "*" || irc::sockets::MatchCIDR(ip, *i))
  43                         {
  44                                 found = true;
  45                                 break;
  46                         }
  47                 }
  48
  49                 if (!found)
  50                 {
  51                         this->ServerInstance->SNO->WriteToSnoMask('l', "Server connection from %s denied (no link blocks with that IP address)", ip);
  52                         ServerInstance->SE->Close(newsock);
  53                         return;
  54                 }
  55         }
  56
  57         if (this->GetIOHook())
  58         {
  59                 this->GetIOHook()->OnRawSocketAccept(newsock, incomingip.c_str(), this->bind_port);
  60         }
  61
  62         /* we don't need a pointer to this, creating it stores it in the necessary places */
  63         new TreeSocket(this->Utils, this->ServerInstance, newsock, ip, this->GetIOHook());
  64         return;
  65 }
  66
  67 /** Yay for fast searches!
  68  * This is hundreds of times faster than recursion
  69  * or even scanning a linked list, especially when
  70  * there are more than a few servers to deal with.
  71  * (read as: lots).
  72  */
  73 TreeServer* SpanningTreeUtilities::FindServer(const std::string &ServerName)
  74 {
  75         if (this->ServerInstance->IsSID(ServerName))
  76                 return this->FindServerID(ServerName);
  77
  78         server_hash::iterator iter = serverlist.find(ServerName.c_str());
  79         if (iter != serverlist.end())
  80         {
  81                 return iter->second;
  82         }
  83         else
  84         {
  85                 return NULL;
  86         }
  87 }
  88
  89 /** Returns the locally connected server we must route a
  90  * message through to reach server 'ServerName'. This
  91  * only applies to one-to-one and not one-to-many routing.
  92  * See the comments for the constructor of TreeServer
  93  * for more details.
  94  */
  95 TreeServer* SpanningTreeUtilities::BestRouteTo(const std::string &ServerName)
  96 {
  97         if (ServerName.c_str() == TreeRoot->GetName() || ServerName == ServerInstance->Config->GetSID())
  98                 return NULL;
  99         TreeServer* Found = FindServer(ServerName);
 100         if (Found)
 101         {
 102                 return Found->GetRoute();
 103         }
 104         else
 105         {
 106                 // Cheat a bit. This allows for (better) working versions of routing commands with nick based prefixes, without hassle
 107                 User *u = ServerInstance->FindNick(ServerName);
 108                 if (u)
 109                 {
 110                         Found = FindServer(u->server);
 111                         if (Found)
 112                                 return Found->GetRoute();
 113                 }
 114
 115                 return NULL;
 116         }
 117 }
 118
 119 /** Find the first server matching a given glob mask.
 120  * Theres no find-using-glob method of hash_map [awwww :-(]
 121  * so instead, we iterate over the list using an iterator
 122  * and match each one until we get a hit. Yes its slow,
 123  * deal with it.
 124  */
 125 TreeServer* SpanningTreeUtilities::FindServerMask(const std::string &ServerName)
 126 {
 127         for (server_hash::iterator i = serverlist.begin(); i != serverlist.end(); i++)
 128         {
 129                 if (InspIRCd::Match(i->first,ServerName))
 130                         return i->second;
 131         }
 132         return NULL;
 133 }
 134
 135 TreeServer* SpanningTreeUtilities::FindServerID(const std::string &id)
 136 {
 137         server_hash::iterator iter = sidlist.find(id);
 138         if (iter != sidlist.end())
 139                 return iter->second;
 140         else
 141                 return NULL;
 142 }
 143
 144 /* A convenient wrapper that returns true if a server exists */
 145 bool SpanningTreeUtilities::IsServer(const std::string &ServerName)
 146 {
 147         return (FindServer(ServerName) != NULL);
 148 }
 149
 150 SpanningTreeUtilities::SpanningTreeUtilities(InspIRCd* Instance, ModuleSpanningTree* C) : ServerInstance(Instance), Creator(C)
 151 {
 152         Bindings.clear();
 153
 154         ServerInstance->Logs->Log("m_spanningtree",DEBUG,"***** Using SID for hash: %s *****", ServerInstance->Config->GetSID().c_str());
 155
 156         this->TreeRoot = new TreeServer(this, ServerInstance, ServerInstance->Config->ServerName, ServerInstance->Config->ServerDesc, ServerInstance->Config->GetSID());
 157         this->ServerUser = new FakeUser(ServerInstance, TreeRoot->GetID());
 158
 159         this->ReadConfiguration(true);
 160 }
 161
 162 SpanningTreeUtilities::~SpanningTreeUtilities()
 163 {
 164         for (unsigned int i = 0; i < Bindings.size(); i++)
 165         {
 166                 delete Bindings[i];
 167         }
 168
 169         while (TreeRoot->ChildCount())
 170         {
 171                 TreeServer* child_server = TreeRoot->GetChild(0);
 172                 if (child_server)
 173                 {
 174                         TreeSocket* sock = child_server->GetSocket();
 175                         ServerInstance->SE->DelFd(sock);
 176                         sock->Close();
 177                 }
 178         }
 179         delete TreeRoot;
 180         ServerUser->uuid = TreeRoot->GetID();
 181         delete ServerUser;
 182         ServerInstance->BufferedSocketCull();
 183 }
 184
 185 void SpanningTreeUtilities::AddThisServer(TreeServer* server, TreeServerList &list)
 186 {
 187         if (list.find(server) == list.end())
 188                 list[server] = server;
 189 }
 190
 191 /* returns a list of DIRECT servernames for a specific channel */
 192 void SpanningTreeUtilities::GetListOfServersForChannel(Channel* c, TreeServerList &list, char status, const CUList &exempt_list)
 193 {
 194         CUList *ulist = c->GetUsers();
 195
 196         for (CUList::iterator i = ulist->begin(); i != ulist->end(); i++)
 197         {
 198                 if (IS_LOCAL(i->first))
 199                         continue;
 200
 201                 if (status && !strchr(c->GetAllPrefixChars(i->first), status))
 202                         continue;
 203
 204                 if (exempt_list.find(i->first) == exempt_list.end())
 205                 {
 206                         TreeServer* best = this->BestRouteTo(i->first->server);
 207                         if (best)
 208                                 AddThisServer(best,list);
 209                 }
 210         }
 211         return;
 212 }
 213
 214 bool SpanningTreeUtilities::DoOneToAllButSenderRaw(const std::string &data, const std::string &omit, const std::string &prefix, const irc::string &command, std::deque<std::string> &params)
 215 {
 216         char pfx = 0;
 217         TreeServer* omitroute = this->BestRouteTo(omit);
 218         if ((command == "NOTICE") || (command == "PRIVMSG"))
 219         {
 220                 if (params.size() >= 2)
 221                 {
 222                         /* Prefixes */
 223                         if (ServerInstance->Modes->FindPrefix(params[0][0]))
 224                         {
 225                                 pfx = params[0][0];
 226                                 params[0] = params[0].substr(1, params[0].length()-1);
 227                         }
 228                         if ((*(params[0].c_str()) != '#') && (*(params[0].c_str()) != '$'))
 229                         {
 230                                 // special routing for private messages/notices
 231                                 User* d = ServerInstance->FindNick(params[0]);
 232                                 if (d)
 233                                 {
 234                                         std::deque<std::string> par;
 235                                         par.push_back(params[0]);
 236                                         par.push_back(":"+params[1]);
 237                                         this->DoOneToOne(prefix,command.c_str(),par,d->server);
 238                                         return true;
 239                                 }
 240                         }
 241                         else if (*(params[0].c_str()) == '$')
 242                         {
 243                                 std::deque<std::string> par;
 244                                 par.push_back(params[0]);
 245                                 par.push_back(":"+params[1]);
 246                                 this->DoOneToAllButSender(prefix,command.c_str(),par,omitroute->GetName());
 247                                 return true;
 248                         }
 249                         else
 250                         {
 251                                 Channel* c = ServerInstance->FindChan(params[0]);
 252                                 User* u = ServerInstance->FindNick(prefix);
 253                                 if (c)
 254                                 {
 255                                         CUList elist;
 256                                         TreeServerList list;
 257                                         FOREACH_MOD(I_OnBuildExemptList, OnBuildExemptList((command == "PRIVMSG" ? MSG_PRIVMSG : MSG_NOTICE), c, u, pfx, elist, params[1]));
 258                                         GetListOfServersForChannel(c,list,pfx,elist);
 259
 260                                         for (TreeServerList::iterator i = list.begin(); i != list.end(); i++)
 261                                         {
 262                                                 TreeSocket* Sock = i->second->GetSocket();
 263                                                 if ((Sock) && (i->second->GetName() != omit) && (omitroute != i->second))
 264                                                 {
 265                                                         Sock->WriteLine(data);
 266                                                 }
 267                                         }
 268                                         return true;
 269                                 }
 270                         }
 271                 }
 272         }
 273         unsigned int items =this->TreeRoot->ChildCount();
 274         for (unsigned int x = 0; x < items; x++)
 275         {
 276                 TreeServer* Route = this->TreeRoot->GetChild(x);
 277                 if ((Route) && (Route->GetSocket()) && (Route->GetName() != omit) && (omitroute != Route))
 278                 {
 279                         TreeSocket* Sock = Route->GetSocket();
 280                         if (Sock)
 281                                 Sock->WriteLine(data);
 282                 }
 283         }
 284         return true;
 285 }
 286
 287 bool SpanningTreeUtilities::DoOneToAllButSender(const std::string &prefix, const std::string &command, std::deque<std::string> &params, std::string omit)
 288 {
 289         TreeServer* omitroute = this->BestRouteTo(omit);
 290         std::string FullLine = ":" + prefix + " " + command;
 291         unsigned int words = params.size();
 292         for (unsigned int x = 0; x < words; x++)
 293         {
 294                 FullLine = FullLine + " " + params[x];
 295         }
 296         unsigned int items = this->TreeRoot->ChildCount();
 297         for (unsigned int x = 0; x < items; x++)
 298         {
 299                 TreeServer* Route = this->TreeRoot->GetChild(x);
 300                 // Send the line IF:
 301                 // The route has a socket (its a direct connection)
 302                 // The route isnt the one to be omitted
 303                 // The route isnt the path to the one to be omitted
 304                 if ((Route) && (Route->GetSocket()) && (Route->GetName() != omit) && (omitroute != Route))
 305                 {
 306                         TreeSocket* Sock = Route->GetSocket();
 307                         if (Sock)
 308                                 Sock->WriteLine(FullLine);
 309                 }
 310         }
 311         return true;
 312 }
 313
 314 bool SpanningTreeUtilities::DoOneToMany(const std::string &prefix, const std::string &command, std::deque<std::string> &params)
 315 {
 316         std::string FullLine = ":" + prefix + " " + command;
 317         unsigned int words = params.size();
 318         for (unsigned int x = 0; x < words; x++)
 319         {
 320                 FullLine = FullLine + " " + params[x];
 321         }
 322         unsigned int items = this->TreeRoot->ChildCount();
 323         for (unsigned int x = 0; x < items; x++)
 324         {
 325                 TreeServer* Route = this->TreeRoot->GetChild(x);
 326                 if (Route && Route->GetSocket())
 327                 {
 328                         TreeSocket* Sock = Route->GetSocket();
 329                         if (Sock)
 330                                 Sock->WriteLine(FullLine);
 331                 }
 332         }
 333         return true;
 334 }
 335
 336 bool SpanningTreeUtilities::DoOneToMany(const char* prefix, const char* command, std::deque<std::string> &params)
 337 {
 338         std::string spfx = prefix;
 339         std::string scmd = command;
 340         return this->DoOneToMany(spfx, scmd, params);
 341 }
 342
 343 bool SpanningTreeUtilities::DoOneToAllButSender(const char* prefix, const char* command, std::deque<std::string> &params, std::string omit)
 344 {
 345         std::string spfx = prefix;
 346         std::string scmd = command;
 347         return this->DoOneToAllButSender(spfx, scmd, params, omit);
 348 }
 349
 350 bool SpanningTreeUtilities::DoOneToOne(const std::string &prefix, const std::string &command, std::deque<std::string> &params, std::string target)
 351 {
 352         TreeServer* Route = this->BestRouteTo(target);
 353         if (Route)
 354         {
 355                 std::string FullLine = ":" + prefix + " " + command;
 356                 unsigned int words = params.size();
 357                 for (unsigned int x = 0; x < words; x++)
 358                 {
 359                         FullLine = FullLine + " " + params[x];
 360                 }
 361                 if (Route && Route->GetSocket())
 362                 {
 363                         TreeSocket* Sock = Route->GetSocket();
 364                         if (Sock)
 365                                 Sock->WriteLine(FullLine);
 366                 }
 367                 return true;
 368         }
 369         else
 370         {
 371                 return false;
 372         }
 373 }
 374
 375 void SpanningTreeUtilities::RefreshIPCache()
 376 {
 377         ValidIPs.clear();
 378         for (std::vector<Link>::iterator L = LinkBlocks.begin(); L != LinkBlocks.end(); L++)
 379         {
 380                 if (L->IPAddr.empty() || L->RecvPass.empty() || L->SendPass.empty() || L->Name.empty() || !L->Port)
 381                 {
 382                         if (L->Name.empty())
 383                         {
 384                                 ServerInstance->Logs->Log("m_spanningtree",DEFAULT,"m_spanningtree: Ignoring a malformed link block (all link blocks require a name!)");
 385                         }
 386                         else
 387                         {
 388                                 ServerInstance->Logs->Log("m_spanningtree",DEFAULT,"m_spanningtree: Ignoring a link block missing recvpass, sendpass, port or ipaddr.");
 389                         }
 390
 391                         /* Invalid link block */
 392                         continue;
 393                 }
 394
 395                 ValidIPs.push_back(L->IPAddr);
 396
 397                 if (L->AllowMask.length())
 398                         ValidIPs.push_back(L->AllowMask);
 399
 400                 /* Needs resolving */
 401                 bool ipvalid = true;
 402                 QueryType start_type = DNS_QUERY_A;
 403 #ifdef IPV6
 404                 start_type = DNS_QUERY_AAAA;
 405                 if (strchr(L->IPAddr.c_str(),':'))
 406                 {
 407                         in6_addr n;
 408                         if (inet_pton(AF_INET6, L->IPAddr.c_str(), &n) < 1)
 409                                 ipvalid = false;
 410                 }
 411                 else
 412 #endif
 413                 {
 414                         in_addr n;
 415                         if (inet_aton(L->IPAddr.c_str(),&n) < 1)
 416                                 ipvalid = false;
 417                 }
 418
 419                 if (!ipvalid)
 420                 {
 421                         try
 422                         {
 423                                 bool cached;
 424                                 SecurityIPResolver* sr = new SecurityIPResolver((Module*)this->Creator, this, ServerInstance, L->IPAddr, *L, cached, start_type);
 425                                 ServerInstance->AddResolver(sr, cached);
 426                         }
 427                         catch (...)
 428                         {
 429                         }
 430                 }
 431         }
 432 }
 433
 434 void SpanningTreeUtilities::ReadConfiguration(bool rebind)
 435 {
 436         ConfigReader* Conf = new ConfigReader(ServerInstance);
 437
 438         /* We don't need to worry about these being *unloaded* on the fly, only loaded,
 439          * because we 'use' the interface locking the module in memory.
 440          */
 441         hooks.clear();
 442         hooknames.clear();
 443         modulelist* ml = ServerInstance->Modules->FindInterface("BufferedSocketHook");
 444
 445         /* Did we find any modules? */
 446         if (ml)
 447         {
 448                 /* Yes, enumerate them all to find out the hook name */
 449                 for (modulelist::iterator m = ml->begin(); m != ml->end(); m++)
 450                 {
 451                         /* Make a request to it for its name, its implementing
 452                          * BufferedSocketHook so we know its safe to do this
 453                          */
 454                         std::string name = BufferedSocketNameRequest((Module*)Creator, *m).Send();
 455                         /* Build a map of them */
 456                         hooks[name.c_str()] = *m;
 457                         hooknames.push_back(name);
 458                 }
 459         }
 460
 461         if (rebind)
 462         {
 463                 for (unsigned int i = 0; i < Bindings.size(); i++)
 464                 {
 465                         delete Bindings[i];
 466                 }
 467                 ServerInstance->BufferedSocketCull();
 468                 Bindings.clear();
 469
 470                 for (int j = 0; j < Conf->Enumerate("bind"); j++)
 471                 {
 472                         std::string Type = Conf->ReadValue("bind","type",j);
 473                         std::string IP = Conf->ReadValue("bind","address",j);
 474                         std::string Port = Conf->ReadValue("bind","port",j);
 475                         std::string transport = Conf->ReadValue("bind","transport",j);
 476                         if (Type == "servers")
 477                         {
 478                                 irc::portparser portrange(Port, false);
 479                                 int portno = -1;
 480
 481                                 if (IP == "*")
 482                                         IP.clear();
 483
 484                                 while ((portno = portrange.GetToken()))
 485                                 {
 486                                         if ((!transport.empty()) && (hooks.find(transport.c_str()) ==  hooks.end()))
 487                                         {
 488                                                 throw CoreException("Can't find transport type '"+transport+"' for port "+IP+":"+Port+" - maybe you forgot to load it BEFORE m_spanningtree in your config file?");
 489                                                 break;
 490                                         }
 491
 492                                         ServerSocketListener *listener = new ServerSocketListener(ServerInstance, this, portno, (char *)IP.c_str());
 493                                         if (listener->GetFd() == -1)
 494                                         {
 495                                                 delete listener;
 496                                                 continue;
 497                                         }
 498
 499                                         if (!transport.empty())
 500                                                 listener->AddIOHook(hooks[transport.c_str()]);
 501
 502                                         Bindings.push_back(listener);
 503                                 }
 504                         }
 505                 }
 506         }
 507         FlatLinks = Conf->ReadFlag("security","flatlinks",0);
 508         HideULines = Conf->ReadFlag("security","hideulines",0);
 509         AnnounceTSChange = Conf->ReadFlag("options","announcets",0);
 510         ChallengeResponse = !Conf->ReadFlag("security", "disablehmac", 0);
 511         quiet_bursts = Conf->ReadFlag("performance", "quietbursts", 0);
 512         PingWarnTime = Conf->ReadInteger("options", "pingwarning", 0, true);
 513         PingFreq = Conf->ReadInteger("options", "serverpingfreq", 0, true);
 514
 515         if (PingFreq == 0)
 516                 PingFreq = 60;
 517
 518         if (PingWarnTime < 0 || PingWarnTime > PingFreq - 1)
 519                 PingWarnTime = 0;
 520
 521         LinkBlocks.clear();
 522         ValidIPs.clear();
 523         for (int j = 0; j < Conf->Enumerate("link"); j++)
 524         {
 525                 Link L;
 526                 std::string Allow = Conf->ReadValue("link", "allowmask", j);
 527                 L.Name = (Conf->ReadValue("link", "name", j)).c_str();
 528                 L.AllowMask = Allow;
 529                 L.IPAddr = Conf->ReadValue("link", "ipaddr", j);
 530                 L.FailOver = Conf->ReadValue("link", "failover", j).c_str();
 531                 L.Port = Conf->ReadInteger("link", "port", j, true);
 532                 L.SendPass = Conf->ReadValue("link", "sendpass", j);
 533                 L.RecvPass = Conf->ReadValue("link", "recvpass", j);
 534                 L.Fingerprint = Conf->ReadValue("link", "fingerprint", j);
 535                 L.AutoConnect = Conf->ReadInteger("link", "autoconnect", j, true);
 536                 L.HiddenFromStats = Conf->ReadFlag("link", "statshidden", j);
 537                 L.Timeout = Conf->ReadInteger("link", "timeout", j, true);
 538                 L.Hook = Conf->ReadValue("link", "transport", j);
 539                 L.Bind = Conf->ReadValue("link", "bind", j);
 540                 L.Hidden = Conf->ReadFlag("link", "hidden", j);
 541
 542                 if ((!L.Hook.empty()) && (hooks.find(L.Hook.c_str()) ==  hooks.end()))
 543                 {
 544                         throw CoreException("Can't find transport type '"+L.Hook+"' for link '"+assign(L.Name)+"' - maybe you forgot to load it BEFORE m_spanningtree in your config file? Skipping <link> tag completely.");
 545                         continue;
 546
 547                 }
 548
 549                 // Fix: Only trip autoconnects if this wouldn't delay autoconnect..
 550                 if (L.NextConnectTime > ((time_t)(ServerInstance->Time() + L.AutoConnect)))
 551                         L.NextConnectTime = ServerInstance->Time() + L.AutoConnect;
 552
 553                 if (L.Name.find('.') == std::string::npos)
 554                         throw CoreException("The link name '"+assign(L.Name)+"' is invalid and must contain at least one '.' character");
 555
 556                 if (L.Name.length() > 64)
 557                         throw CoreException("The link name '"+assign(L.Name)+"' is longer than 64 characters!");
 558
 559                 if ((!L.IPAddr.empty()) && (!L.RecvPass.empty()) && (!L.SendPass.empty()) && (!L.Name.empty()) && (L.Port))
 560                 {
 561                         if (Allow.length())
 562                                 ValidIPs.push_back(Allow);
 563
 564                         ValidIPs.push_back(L.IPAddr);
 565
 566                         /* Needs resolving */
 567                         bool ipvalid = true;
 568                         QueryType start_type = DNS_QUERY_A;
 569 #ifdef IPV6
 570                         start_type = DNS_QUERY_AAAA;
 571                         if (strchr(L.IPAddr.c_str(),':'))
 572                         {
 573                                 in6_addr n;
 574                                 if (inet_pton(AF_INET6, L.IPAddr.c_str(), &n) < 1)
 575                                         ipvalid = false;
 576                         }
 577                         else
 578                         {
 579                                 in_addr n;
 580                                 if (inet_aton(L.IPAddr.c_str(),&n) < 1)
 581                                         ipvalid = false;
 582                         }
 583 #else
 584                         in_addr n;
 585                         if (inet_aton(L.IPAddr.c_str(),&n) < 1)
 586                                 ipvalid = false;
 587 #endif
 588
 589                         if (!ipvalid)
 590                         {
 591                                 try
 592                                 {
 593                                         bool cached;
 594                                         SecurityIPResolver* sr = new SecurityIPResolver((Module*)this->Creator, this, ServerInstance, L.IPAddr, L, cached, start_type);
 595                                         ServerInstance->AddResolver(sr, cached);
 596                                 }
 597                                 catch (...)
 598                                 {
 599                                 }
 600                         }
 601                 }
 602                 else
 603                 {
 604                         if (L.IPAddr.empty())
 605                         {
 606                                 L.IPAddr = "*";
 607                                 ValidIPs.push_back("*");
 608                                 ServerInstance->Logs->Log("m_spanningtree",DEFAULT,"Configuration warning: Link block " + assign(L.Name) + " has no IP defined! This will allow any IP to connect as this server, and MAY not be what you want.");
 609                         }
 610
 611                         if (L.RecvPass.empty())
 612                         {
 613                                 throw CoreException("Invalid configuration for server '"+assign(L.Name)+"', recvpass not defined!");
 614                         }
 615
 616                         if (L.SendPass.empty())
 617                         {
 618                                 throw CoreException("Invalid configuration for server '"+assign(L.Name)+"', sendpass not defined!");
 619                         }
 620
 621                         if (L.Name.empty())
 622                         {
 623                                 throw CoreException("Invalid configuration, link tag without a name! IP address: "+L.IPAddr);
 624                         }
 625
 626                         if (!L.Port)
 627                         {
 628                                 ServerInstance->Logs->Log("m_spanningtree",DEFAULT,"Configuration warning: Link block " + assign(L.Name) + " has no port defined, you will not be able to /connect it.");
 629                         }
 630                 }
 631
 632                 LinkBlocks.push_back(L);
 633         }
 634         delete Conf;
 635 }
 636
 637 void SpanningTreeUtilities::DoFailOver(Link* x)
 638 {
 639         if (x->FailOver.length())
 640         {
 641                 if (x->FailOver == x->Name)
 642                 {
 643                         this->ServerInstance->SNO->WriteToSnoMask('l', "FAILOVER: Some muppet configured the failover for server \002%s\002 to point at itself. Not following it!", x->Name.c_str());
 644                         return;
 645                 }
 646                 Link* TryThisOne = this->FindLink(x->FailOver.c_str());
 647                 if (TryThisOne)
 648                 {
 649                         TreeServer* CheckDupe = this->FindServer(x->FailOver.c_str());
 650                         if (CheckDupe)
 651                         {
 652                                 ServerInstance->Logs->Log("m_spanningtree",DEBUG,"Skipping existing failover: %s", x->FailOver.c_str());
 653                         }
 654                         else
 655                         {
 656                                 this->ServerInstance->SNO->WriteToSnoMask('l', "FAILOVER: Trying failover link for \002%s\002: \002%s\002...", x->Name.c_str(), TryThisOne->Name.c_str());
 657                                 Creator->ConnectServer(TryThisOne);
 658                         }
 659                 }
 660                 else
 661                 {
 662                         this->ServerInstance->SNO->WriteToSnoMask('l', "FAILOVER: Invalid failover server specified for server \002%s\002, will not follow!", x->Name.c_str());
 663                 }
 664         }
 665 }
 666
 667 Link* SpanningTreeUtilities::FindLink(const std::string& name)
 668 {
 669         for (std::vector<Link>::iterator x = LinkBlocks.begin(); x != LinkBlocks.end(); x++)
 670         {
 671                 if (InspIRCd::Match(x->Name.c_str(), name.c_str()))
 672                 {
 673                         return &(*x);
 674                 }
 675         }
 676         return NULL;
 677 }