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                         allow_empty_last_param = false;
  77                         works_before_reg = true;
  78                         this->syntax = "password client hostname ip";
  79                 }
  80                 CmdResult Handle(const std::vector<std::string> &parameters, User *user)
  81                 {
  82                         if(user->registered == REG_ALL)
  83                                 return CMD_FAILURE;
  84
  85                         irc::sockets::sockaddrs ipaddr;
  86                         if (!irc::sockets::aptosa(parameters[3], 0, ipaddr))
  87                         {
  88                                 IS_LOCAL(user)->CommandFloodPenalty += 5000;
  89                                 ServerInstance->SNO->WriteGlobalSno('a', "Connecting user %s tried to use WEBIRC but gave an invalid IP address.", user->GetFullRealHost().c_str());
  90                                 return CMD_FAILURE;
  91                         }
  92
  93                         for(CGIHostlist::iterator iter = Hosts.begin(); iter != Hosts.end(); iter++)
  94                         {
  95                                 if(InspIRCd::Match(user->host, iter->hostmask, ascii_case_insensitive_map) || InspIRCd::MatchCIDR(user->GetIPString(), iter->hostmask, ascii_case_insensitive_map))
  96                                 {
  97                                         if(iter->type == WEBIRC && parameters[0] == iter->password)
  98                                         {
  99                                                 realhost.set(user, user->host);
 100                                                 realip.set(user, user->GetIPString());
 101
 102                                                 // Check if we're happy with the provided hostname. If it's problematic then use the IP instead.
 103                                                 bool host_ok = (parameters[2].length() < 64) && (parameters[2].find_first_not_of("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.:-") == std::string::npos);
 104                                                 const std::string& newhost = (host_ok ? parameters[2] : parameters[3]);
 105
 106                                                 if (notify)
 107                                                         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(), newhost.c_str(), user->host.c_str());
 108
 109                                                 webirc_hostname.set(user, newhost);
 110                                                 webirc_ip.set(user, parameters[3]);
 111                                                 return CMD_SUCCESS;
 112                                         }
 113                                 }
 114                         }
 115
 116                         IS_LOCAL(user)->CommandFloodPenalty += 5000;
 117                         ServerInstance->SNO->WriteGlobalSno('a', "Connecting user %s tried to use WEBIRC, but didn't match any configured webirc blocks.", user->GetFullRealHost().c_str());
 118                         return CMD_FAILURE;
 119                 }
 120 };
 121
 122
 123 /** Resolver for CGI:IRC hostnames encoded in ident/GECOS
 124  */
 125 class CGIResolver : public Resolver
 126 {
 127         std::string typ;
 128         std::string theiruid;
 129         LocalIntExt& waiting;
 130         bool notify;
 131  public:
 132         CGIResolver(Module* me, bool NotifyOpers, const std::string &source, LocalUser* u,
 133                         const std::string &type, bool &cached, LocalIntExt& ext)
 134                 : Resolver(source, DNS_QUERY_PTR4, cached, me), typ(type), theiruid(u->uuid),
 135                 waiting(ext), notify(NotifyOpers)
 136         {
 137         }
 138
 139         virtual void OnLookupComplete(const std::string &result, unsigned int ttl, bool cached)
 140         {
 141                 /* Check the user still exists */
 142                 User* them = ServerInstance->FindUUID(theiruid);
 143                 if ((them) && (!them->quitting))
 144                 {
 145                         if (notify)
 146                                 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());
 147
 148                         if (result.length() > 64)
 149                                 return;
 150                         them->host = result;
 151                         them->dhost = result;
 152                         them->InvalidateCache();
 153                         them->CheckLines(true);
 154                 }
 155         }
 156
 157         virtual void OnError(ResolverError e, const std::string &errormessage)
 158         {
 159                 if (!notify)
 160                         return;
 161
 162                 User* them = ServerInstance->FindUUID(theiruid);
 163                 if ((them) && (!them->quitting))
 164                 {
 165                         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());
 166                 }
 167         }
 168
 169         virtual ~CGIResolver()
 170         {
 171                 User* them = ServerInstance->FindUUID(theiruid);
 172                 if (!them)
 173                         return;
 174                 int count = waiting.get(them);
 175                 if (count)
 176                         waiting.set(them, count - 1);
 177         }
 178 };
 179
 180 class ModuleCgiIRC : public Module
 181 {
 182         CommandWebirc cmd;
 183         LocalIntExt waiting;
 184
 185         static void RecheckClass(LocalUser* user)
 186         {
 187                 user->MyClass = NULL;
 188                 user->SetClass();
 189                 user->CheckClass();
 190         }
 191
 192         static void ChangeIP(LocalUser* user, const std::string& newip)
 193         {
 194                 ServerInstance->Users->RemoveCloneCounts(user);
 195                 user->SetClientIP(newip.c_str());
 196                 ServerInstance->Users->AddLocalClone(user);
 197                 ServerInstance->Users->AddGlobalClone(user);
 198         }
 199
 200         void HandleIdentOrPass(LocalUser* user, const std::string& newip, bool was_pass)
 201         {
 202                 cmd.realhost.set(user, user->host);
 203                 cmd.realip.set(user, user->GetIPString());
 204                 ChangeIP(user, newip);
 205                 user->host = user->dhost = user->GetIPString();
 206                 user->InvalidateCache();
 207                 RecheckClass(user);
 208                 // Don't create the resolver if the core couldn't put the user in a connect class or when dns is disabled
 209                 if (user->quitting || ServerInstance->Config->NoUserDns)
 210                         return;
 211
 212                 try
 213                 {
 214                         bool cached;
 215                         CGIResolver* r = new CGIResolver(this, cmd.notify, newip, user, (was_pass ? "PASS" : "IDENT"), cached, waiting);
 216                         waiting.set(user, waiting.get(user) + 1);
 217                         ServerInstance->AddResolver(r, cached);
 218                 }
 219                 catch (...)
 220                 {
 221                         if (cmd.notify)
 222                                  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());
 223                 }
 224         }
 225
 226 public:
 227         ModuleCgiIRC() : cmd(this), waiting("cgiirc-delay", this)
 228         {
 229         }
 230
 231         void init()
 232         {
 233                 OnRehash(NULL);
 234                 ServiceProvider* providerlist[] = { &cmd, &cmd.realhost, &cmd.realip, &cmd.webirc_hostname, &cmd.webirc_ip, &waiting };
 235                 ServerInstance->Modules->AddServices(providerlist, sizeof(providerlist)/sizeof(ServiceProvider*));
 236
 237                 Implementation eventlist[] = { I_OnRehash, I_OnUserRegister, I_OnCheckReady };
 238                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 239         }
 240
 241         void OnRehash(User* user)
 242         {
 243                 cmd.Hosts.clear();
 244
 245                 // Do we send an oper notice when a CGI:IRC has their host changed?
 246                 cmd.notify = ServerInstance->Config->ConfValue("cgiirc")->getBool("opernotice", true);
 247
 248                 ConfigTagList tags = ServerInstance->Config->ConfTags("cgihost");
 249                 for (ConfigIter i = tags.first; i != tags.second; ++i)
 250                 {
 251                         ConfigTag* tag = i->second;
 252                         std::string hostmask = tag->getString("mask"); // An allowed CGI:IRC host
 253                         std::string type = tag->getString("type"); // What type of user-munging we do on this host.
 254                         std::string password = tag->getString("password");
 255
 256                         if(hostmask.length())
 257                         {
 258                                 if (type == "webirc" && password.empty())
 259                                 {
 260                                         ServerInstance->Logs->Log("CONFIG",DEFAULT, "m_cgiirc: Missing password in config: %s", hostmask.c_str());
 261                                 }
 262                                 else
 263                                 {
 264                                         CGItype cgitype;
 265                                         if (type == "pass")
 266                                                 cgitype = PASS;
 267                                         else if (type == "ident")
 268                                                 cgitype = IDENT;
 269                                         else if (type == "passfirst")
 270                                                 cgitype = PASSFIRST;
 271                                         else if (type == "webirc")
 272                                                 cgitype = WEBIRC;
 273                                         else
 274                                         {
 275                                                 cgitype = PASS;
 276                                                 ServerInstance->Logs->Log("CONFIG",DEFAULT, "m_cgiirc.so: Invalid <cgihost:type> value in config: %s, setting it to \"pass\"", type.c_str());
 277                                         }
 278
 279                                         cmd.Hosts.push_back(CGIhost(hostmask, cgitype, password));
 280                                 }
 281                         }
 282                         else
 283                         {
 284                                 ServerInstance->Logs->Log("CONFIG",DEFAULT, "m_cgiirc.so: Invalid <cgihost:mask> value in config: %s", hostmask.c_str());
 285                                 continue;
 286                         }
 287                 }
 288         }
 289
 290         ModResult OnCheckReady(LocalUser *user)
 291         {
 292                 if (waiting.get(user))
 293                         return MOD_RES_DENY;
 294
 295                 std::string *webirc_ip = cmd.webirc_ip.get(user);
 296                 if (!webirc_ip)
 297                         return MOD_RES_PASSTHRU;
 298
 299                 ChangeIP(user, *webirc_ip);
 300
 301                 std::string* webirc_hostname = cmd.webirc_hostname.get(user);
 302                 user->host = user->dhost = (webirc_hostname ? *webirc_hostname : user->GetIPString());
 303                 user->InvalidateCache();
 304
 305                 RecheckClass(user);
 306                 if (user->quitting)
 307                         return MOD_RES_DENY;
 308
 309                 user->CheckLines(true);
 310                 if (user->quitting)
 311                         return MOD_RES_DENY;
 312
 313                 cmd.webirc_hostname.unset(user);
 314                 cmd.webirc_ip.unset(user);
 315
 316                 return MOD_RES_PASSTHRU;
 317         }
 318
 319         ModResult OnUserRegister(LocalUser* user)
 320         {
 321                 for(CGIHostlist::iterator iter = cmd.Hosts.begin(); iter != cmd.Hosts.end(); iter++)
 322                 {
 323                         if(InspIRCd::Match(user->host, iter->hostmask, ascii_case_insensitive_map) || InspIRCd::MatchCIDR(user->GetIPString(), iter->hostmask, ascii_case_insensitive_map))
 324                         {
 325                                 // Deal with it...
 326                                 if(iter->type == PASS)
 327                                 {
 328                                         CheckPass(user); // We do nothing if it fails so...
 329                                         user->CheckLines(true);
 330                                 }
 331                                 else if(iter->type == PASSFIRST && !CheckPass(user))
 332                                 {
 333                                         // If the password lookup failed, try the ident
 334                                         CheckIdent(user);       // If this fails too, do nothing
 335                                         user->CheckLines(true);
 336                                 }
 337                                 else if(iter->type == IDENT)
 338                                 {
 339                                         CheckIdent(user); // Nothing on failure.
 340                                         user->CheckLines(true);
 341                                 }
 342                                 else if(iter->type == IDENTFIRST && !CheckIdent(user))
 343                                 {
 344                                         // If the ident lookup fails, try the password.
 345                                         CheckPass(user);
 346                                         user->CheckLines(true);
 347                                 }
 348                                 else if(iter->type == WEBIRC)
 349                                 {
 350                                         // We don't need to do anything here
 351                                 }
 352                                 return MOD_RES_PASSTHRU;
 353                         }
 354                 }
 355                 return MOD_RES_PASSTHRU;
 356         }
 357
 358         bool CheckPass(LocalUser* user)
 359         {
 360                 if(IsValidHost(user->password))
 361                 {
 362                         HandleIdentOrPass(user, user->password, true);
 363                         user->password.clear();
 364                         return true;
 365                 }
 366
 367                 return false;
 368         }
 369
 370         bool CheckIdent(LocalUser* user)
 371         {
 372                 const char* ident;
 373                 in_addr newip;
 374
 375                 if (user->ident.length() == 8)
 376                         ident = user->ident.c_str();
 377                 else if (user->ident.length() == 9 && user->ident[0] == '~')
 378                         ident = user->ident.c_str() + 1;
 379                 else
 380                         return false;
 381
 382                 errno = 0;
 383                 unsigned long ipaddr = strtoul(ident, NULL, 16);
 384                 if (errno)
 385                         return false;
 386                 newip.s_addr = htonl(ipaddr);
 387                 std::string newipstr(inet_ntoa(newip));
 388
 389                 user->ident = "~cgiirc";
 390                 HandleIdentOrPass(user, newipstr, false);
 391
 392                 return true;
 393         }
 394
 395         bool IsValidHost(const std::string &host)
 396         {
 397                 if(!host.size() || host.size() > 64)
 398                         return false;
 399
 400                 for(unsigned int i = 0; i < host.size(); i++)
 401                 {
 402                         if(     ((host[i] >= '0') && (host[i] <= '9')) ||
 403                                         ((host[i] >= 'A') && (host[i] <= 'Z')) ||
 404                                         ((host[i] >= 'a') && (host[i] <= 'z')) ||
 405                                         ((host[i] == '-') && (i > 0) && (i+1 < host.size()) && (host[i-1] != '.') && (host[i+1] != '.')) ||
 406                                         ((host[i] == '.') && (i > 0) && (i+1 < host.size())) )
 407
 408                                 continue;
 409                         else
 410                                 return false;
 411                 }
 412
 413                 return true;
 414         }
 415
 416         virtual Version GetVersion()
 417         {
 418                 return Version("Change user's hosts connecting from known CGI:IRC hosts",VF_VENDOR);
 419         }
 420
 421 };
 422
 423 MODULE_INIT(ModuleCgiIRC)