src/modules/m_cgiirc.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
   5  *   Copyright (C) 2007-2008 John Brooks <john.brooks@dereferenced.net>
   6  *   Copyright (C) 2008 Pippijn van Steenhoven <pip88nl@gmail.com>
   7  *   Copyright (C) 2006-2008 Craig Edwards <craigedwards@brainbox.cc>
   8  *   Copyright (C) 2007 Robin Burchell <robin+git@viroteck.net>
   9  *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
  10  *   Copyright (C) 2006 Oliver Lupton <oliverlupton@gmail.com>
  11  *
  12  * This file is part of InspIRCd.  InspIRCd is free software: you can
  13  * redistribute it and/or modify it under the terms of the GNU General Public
  14  * License as published by the Free Software Foundation, version 2.
  15  *
  16  * This program is distributed in the hope that it will be useful, but WITHOUT
  17  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  18  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  19  * details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  */
  24
  25
  26 #include "inspircd.h"
  27 #include "xline.h"
  28
  29 /* $ModDesc: Change user's hosts connecting from known CGI:IRC hosts */
  30
  31 enum CGItype { PASS, IDENT, PASSFIRST, IDENTFIRST, WEBIRC };
  32
  33
  34 /** Holds a CGI site's details
  35  */
  36 class CGIhost
  37 {
  38 public:
  39         std::string hostmask;
  40         CGItype type;
  41         std::string password;
  42
  43         CGIhost(const std::string &mask, CGItype t, const std::string &spassword)
  44         : hostmask(mask), type(t), password(spassword)
  45         {
  46         }
  47 };
  48 typedef std::vector<CGIhost> CGIHostlist;
  49
  50 /*
  51  * WEBIRC
  52  *  This is used for the webirc method of CGIIRC auth, and is (really) the best way to do these things.
  53  *  Syntax: WEBIRC password client hostname ip
  54  *  Where password is a shared key, client is the name of the "client" and version (e.g. cgiirc), hostname
  55  *  is the resolved host of the client issuing the command and IP is the real IP of the client.
  56  *
  57  * How it works:
  58  *  To tie in with the rest of cgiirc module, and to avoid race conditions, /webirc is only processed locally
  59  *  and simply sets metadata on the user, which is later decoded on full connect to give something meaningful.
  60  */
  61 class CommandWebirc : public Command
  62 {
  63  public:
  64         bool notify;
  65         StringExtItem realhost;
  66         StringExtItem realip;
  67         LocalStringExt webirc_hostname;
  68         LocalStringExt webirc_ip;
  69
  70         CGIHostlist Hosts;
  71         CommandWebirc(Module* Creator)
  72                 : Command(Creator, "WEBIRC", 4),
  73                   realhost("cgiirc_realhost", Creator), realip("cgiirc_realip", Creator),
  74                   webirc_hostname("cgiirc_webirc_hostname", Creator), webirc_ip("cgiirc_webirc_ip", Creator)
  75                 {
  76                         works_before_reg = true;
  77                         this->syntax = "password client hostname ip";
  78                 }
  79                 CmdResult Handle(const std::vector<std::string> &parameters, User *user)
  80                 {
  81                         if(user->registered == REG_ALL)
  82                                 return CMD_FAILURE;
  83
  84                         for(CGIHostlist::iterator iter = Hosts.begin(); iter != Hosts.end(); iter++)
  85                         {
  86                                 if(InspIRCd::Match(user->host, iter->hostmask, ascii_case_insensitive_map) || InspIRCd::MatchCIDR(user->GetIPString(), iter->hostmask, ascii_case_insensitive_map))
  87                                 {
  88                                         if(iter->type == WEBIRC && parameters[0] == iter->password)
  89                                         {
  90                                                 realhost.set(user, user->host);
  91                                                 realip.set(user, user->GetIPString());
  92                                                 if (notify)
  93                                                         ServerInstance->SNO->WriteGlobalSno('a', "Connecting user %s detected as using CGI:IRC (%s), changing real host to %s from %s", user->nick.c_str(), user->host.c_str(), parameters[2].c_str(), user->host.c_str());
  94
  95                                                 // Check if we're happy with the provided hostname. If it's problematic then make sure we won't set a host later, just the IP
  96                                                 if (parameters[2].length() < 64)
  97                                                         webirc_hostname.set(user, parameters[2]);
  98                                                 else
  99                                                         webirc_hostname.unset(user);
 100
 101                                                 webirc_ip.set(user, parameters[3]);
 102                                                 return CMD_SUCCESS;
 103                                         }
 104                                 }
 105                         }
 106
 107                         ServerInstance->SNO->WriteGlobalSno('a', "Connecting user %s tried to use WEBIRC, but didn't match any configured webirc blocks.", user->GetFullRealHost().c_str());
 108                         return CMD_FAILURE;
 109                 }
 110 };
 111
 112
 113 /** Resolver for CGI:IRC hostnames encoded in ident/GECOS
 114  */
 115 class CGIResolver : public Resolver
 116 {
 117         std::string typ;
 118         std::string theiruid;
 119         LocalIntExt& waiting;
 120         bool notify;
 121  public:
 122         CGIResolver(Module* me, bool NotifyOpers, const std::string &source, LocalUser* u,
 123                         const std::string &type, bool &cached, LocalIntExt& ext)
 124                 : Resolver(source, DNS_QUERY_PTR4, cached, me), typ(type), theiruid(u->uuid),
 125                 waiting(ext), notify(NotifyOpers)
 126         {
 127         }
 128
 129         virtual void OnLookupComplete(const std::string &result, unsigned int ttl, bool cached)
 130         {
 131                 /* Check the user still exists */
 132                 User* them = ServerInstance->FindUUID(theiruid);
 133                 if ((them) && (!them->quitting))
 134                 {
 135                         if (notify)
 136                                 ServerInstance->SNO->WriteGlobalSno('a', "Connecting user %s detected as using CGI:IRC (%s), changing real host to %s from %s", them->nick.c_str(), them->host.c_str(), result.c_str(), typ.c_str());
 137
 138                         if (result.length() > 64)
 139                                 return;
 140                         them->host = result;
 141                         them->dhost = result;
 142                         them->InvalidateCache();
 143                         them->CheckLines(true);
 144                 }
 145         }
 146
 147         virtual void OnError(ResolverError e, const std::string &errormessage)
 148         {
 149                 if (!notify)
 150                         return;
 151
 152                 User* them = ServerInstance->FindUUID(theiruid);
 153                 if ((them) && (!them->quitting))
 154                 {
 155                         ServerInstance->SNO->WriteToSnoMask('a', "Connecting user %s detected as using CGI:IRC (%s), but their host can't be resolved from their %s!", them->nick.c_str(), them->host.c_str(), typ.c_str());
 156                 }
 157         }
 158
 159         virtual ~CGIResolver()
 160         {
 161                 User* them = ServerInstance->FindUUID(theiruid);
 162                 if (!them)
 163                         return;
 164                 int count = waiting.get(them);
 165                 if (count)
 166                         waiting.set(them, count - 1);
 167         }
 168 };
 169
 170 class ModuleCgiIRC : public Module
 171 {
 172         CommandWebirc cmd;
 173         LocalIntExt waiting;
 174
 175         static void RecheckElineAndClass(LocalUser* user)
 176         {
 177                 user->exempt = (ServerInstance->XLines->MatchesLine("E", user) != NULL);
 178                 user->SetClass();
 179                 user->CheckClass();
 180         }
 181
 182         static void ChangeIP(LocalUser* user, const std::string& newip)
 183         {
 184                 ServerInstance->Users->RemoveCloneCounts(user);
 185                 user->SetClientIP(newip.c_str());
 186                 ServerInstance->Users->AddLocalClone(user);
 187                 ServerInstance->Users->AddGlobalClone(user);
 188         }
 189
 190         void HandleIdentOrPass(LocalUser* user, const std::string& newip, bool was_pass)
 191         {
 192                 cmd.realhost.set(user, user->host);
 193                 cmd.realip.set(user, user->GetIPString());
 194                 ChangeIP(user, newip);
 195                 user->host = user->dhost = user->GetIPString();
 196                 user->InvalidateCache();
 197                 RecheckElineAndClass(user);
 198                 // Don't create the resolver if the core couldn't put the user in a connect class or when dns is disabled
 199                 if (user->quitting || ServerInstance->Config->NoUserDns)
 200                         return;
 201
 202                 try
 203                 {
 204                         bool cached;
 205                         CGIResolver* r = new CGIResolver(this, cmd.notify, newip, user, (was_pass ? "PASS" : "IDENT"), cached, waiting);
 206                         ServerInstance->AddResolver(r, cached);
 207                         waiting.set(user, waiting.get(user) + 1);
 208                 }
 209                 catch (...)
 210                 {
 211                         if (cmd.notify)
 212                                  ServerInstance->SNO->WriteToSnoMask('a', "Connecting user %s detected as using CGI:IRC (%s), but I could not resolve their hostname!", user->nick.c_str(), user->host.c_str());
 213                 }
 214         }
 215
 216 public:
 217         ModuleCgiIRC() : cmd(this), waiting("cgiirc-delay", this)
 218         {
 219         }
 220
 221         void init()
 222         {
 223                 OnRehash(NULL);
 224                 ServerInstance->AddCommand(&cmd);
 225                 ServerInstance->Extensions.Register(&cmd.realhost);
 226                 ServerInstance->Extensions.Register(&cmd.realip);
 227                 ServerInstance->Extensions.Register(&cmd.webirc_hostname);
 228                 ServerInstance->Extensions.Register(&cmd.webirc_ip);
 229                 ServerInstance->Extensions.Register(&waiting);
 230
 231                 Implementation eventlist[] = { I_OnRehash, I_OnUserRegister, I_OnCheckReady };
 232                 ServerInstance->Modules->Attach(eventlist, this, 3);
 233         }
 234
 235         void OnRehash(User* user)
 236         {
 237                 cmd.Hosts.clear();
 238
 239                 // Do we send an oper notice when a CGI:IRC has their host changed?
 240                 cmd.notify = ServerInstance->Config->ConfValue("cgiirc")->getBool("opernotice", true);
 241
 242                 ConfigTagList tags = ServerInstance->Config->ConfTags("cgihost");
 243                 for (ConfigIter i = tags.first; i != tags.second; ++i)
 244                 {
 245                         ConfigTag* tag = i->second;
 246                         std::string hostmask = tag->getString("mask"); // An allowed CGI:IRC host
 247                         std::string type = tag->getString("type"); // What type of user-munging we do on this host.
 248                         std::string password = tag->getString("password");
 249
 250                         if(hostmask.length())
 251                         {
 252                                 if (type == "webirc" && password.empty())
 253                                 {
 254                                         ServerInstance->Logs->Log("CONFIG",DEFAULT, "m_cgiirc: Missing password in config: %s", hostmask.c_str());
 255                                 }
 256                                 else
 257                                 {
 258                                         CGItype cgitype;
 259                                         if (type == "pass")
 260                                                 cgitype = PASS;
 261                                         else if (type == "ident")
 262                                                 cgitype = IDENT;
 263                                         else if (type == "passfirst")
 264                                                 cgitype = PASSFIRST;
 265                                         else if (type == "webirc")
 266                                                 cgitype = WEBIRC;
 267                                         else
 268                                         {
 269                                                 cgitype = PASS;
 270                                                 ServerInstance->Logs->Log("CONFIG",DEFAULT, "m_cgiirc.so: Invalid <cgihost:type> value in config: %s, setting it to \"pass\"", type.c_str());
 271                                         }
 272
 273                                         cmd.Hosts.push_back(CGIhost(hostmask, cgitype, password));
 274                                 }
 275                         }
 276                         else
 277                         {
 278                                 ServerInstance->Logs->Log("CONFIG",DEFAULT, "m_cgiirc.so: Invalid <cgihost:mask> value in config: %s", hostmask.c_str());
 279                                 continue;
 280                         }
 281                 }
 282         }
 283
 284         ModResult OnCheckReady(LocalUser *user)
 285         {
 286                 if (waiting.get(user))
 287                         return MOD_RES_DENY;
 288
 289                 std::string *webirc_ip = cmd.webirc_ip.get(user);
 290                 if (!webirc_ip)
 291                         return MOD_RES_PASSTHRU;
 292
 293                 ChangeIP(user, *webirc_ip);
 294
 295                 std::string* webirc_hostname = cmd.webirc_hostname.get(user);
 296                 user->host = user->dhost = (webirc_hostname ? *webirc_hostname : user->GetIPString());
 297
 298                 RecheckElineAndClass(user);
 299                 if (user->quitting)
 300                         return MOD_RES_DENY;
 301
 302                 user->CheckLines(true);
 303                 if (user->quitting)
 304                         return MOD_RES_DENY;
 305
 306                 cmd.webirc_hostname.unset(user);
 307                 cmd.webirc_ip.unset(user);
 308
 309                 return MOD_RES_PASSTHRU;
 310         }
 311
 312         ModResult OnUserRegister(LocalUser* user)
 313         {
 314                 for(CGIHostlist::iterator iter = cmd.Hosts.begin(); iter != cmd.Hosts.end(); iter++)
 315                 {
 316                         if(InspIRCd::Match(user->host, iter->hostmask, ascii_case_insensitive_map) || InspIRCd::MatchCIDR(user->GetIPString(), iter->hostmask, ascii_case_insensitive_map))
 317                         {
 318                                 // Deal with it...
 319                                 if(iter->type == PASS)
 320                                 {
 321                                         CheckPass(user); // We do nothing if it fails so...
 322                                         user->CheckLines(true);
 323                                 }
 324                                 else if(iter->type == PASSFIRST && !CheckPass(user))
 325                                 {
 326                                         // If the password lookup failed, try the ident
 327                                         CheckIdent(user);       // If this fails too, do nothing
 328                                         user->CheckLines(true);
 329                                 }
 330                                 else if(iter->type == IDENT)
 331                                 {
 332                                         CheckIdent(user); // Nothing on failure.
 333                                         user->CheckLines(true);
 334                                 }
 335                                 else if(iter->type == IDENTFIRST && !CheckIdent(user))
 336                                 {
 337                                         // If the ident lookup fails, try the password.
 338                                         CheckPass(user);
 339                                         user->CheckLines(true);
 340                                 }
 341                                 else if(iter->type == WEBIRC)
 342                                 {
 343                                         // We don't need to do anything here
 344                                 }
 345                                 return MOD_RES_PASSTHRU;
 346                         }
 347                 }
 348                 return MOD_RES_PASSTHRU;
 349         }
 350
 351         bool CheckPass(LocalUser* user)
 352         {
 353                 if(IsValidHost(user->password))
 354                 {
 355                         HandleIdentOrPass(user, user->password, true);
 356                         user->password.clear();
 357                         return true;
 358                 }
 359
 360                 return false;
 361         }
 362
 363         bool CheckIdent(LocalUser* user)
 364         {
 365                 const char* ident;
 366                 in_addr newip;
 367
 368                 if (user->ident.length() == 8)
 369                         ident = user->ident.c_str();
 370                 else if (user->ident.length() == 9 && user->ident[0] == '~')
 371                         ident = user->ident.c_str() + 1;
 372                 else
 373                         return false;
 374
 375                 errno = 0;
 376                 unsigned long ipaddr = strtoul(ident, NULL, 16);
 377                 if (errno)
 378                         return false;
 379                 newip.s_addr = htonl(ipaddr);
 380                 std::string newipstr(inet_ntoa(newip));
 381
 382                 user->ident = "~cgiirc";
 383                 HandleIdentOrPass(user, newipstr, false);
 384
 385                 return true;
 386         }
 387
 388         bool IsValidHost(const std::string &host)
 389         {
 390                 if(!host.size() || host.size() > 64)
 391                         return false;
 392
 393                 for(unsigned int i = 0; i < host.size(); i++)
 394                 {
 395                         if(     ((host[i] >= '0') && (host[i] <= '9')) ||
 396                                         ((host[i] >= 'A') && (host[i] <= 'Z')) ||
 397                                         ((host[i] >= 'a') && (host[i] <= 'z')) ||
 398                                         ((host[i] == '-') && (i > 0) && (i+1 < host.size()) && (host[i-1] != '.') && (host[i+1] != '.')) ||
 399                                         ((host[i] == '.') && (i > 0) && (i+1 < host.size())) )
 400
 401                                 continue;
 402                         else
 403                                 return false;
 404                 }
 405
 406                 return true;
 407         }
 408
 409         virtual Version GetVersion()
 410         {
 411                 return Version("Change user's hosts connecting from known CGI:IRC hosts",VF_VENDOR);
 412         }
 413
 414 };
 415
 416 MODULE_INIT(ModuleCgiIRC)