src/modules/m_sasl.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
   5  *   Copyright (C) 2008 Craig Edwards <craigedwards@brainbox.cc>
   6  *
   7  * This file is part of InspIRCd.  InspIRCd is free software: you can
   8  * redistribute it and/or modify it under the terms of the GNU General Public
   9  * License as published by the Free Software Foundation, version 2.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  13  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  14  * details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20
  21 #include "inspircd.h"
  22 #include "modules/cap.h"
  23 #include "modules/account.h"
  24 #include "modules/sasl.h"
  25 #include "modules/ssl.h"
  26 #include "modules/spanningtree.h"
  27
  28 static std::string sasl_target;
  29
  30 class ServerTracker : public SpanningTreeEventListener
  31 {
  32         bool online;
  33
  34         void Update(const Server* server, bool linked)
  35         {
  36                 if (sasl_target == "*")
  37                         return;
  38
  39                 if (InspIRCd::Match(server->GetName(), sasl_target))
  40                 {
  41                         ServerInstance->Logs->Log(MODNAME, LOG_VERBOSE, "SASL target server \"%s\" %s", sasl_target.c_str(), (linked ? "came online" : "went offline"));
  42                         online = linked;
  43                 }
  44         }
  45
  46         void OnServerLink(const Server* server) CXX11_OVERRIDE
  47         {
  48                 Update(server, true);
  49         }
  50
  51         void OnServerSplit(const Server* server) CXX11_OVERRIDE
  52         {
  53                 Update(server, false);
  54         }
  55
  56  public:
  57         ServerTracker(Module* mod)
  58                 : SpanningTreeEventListener(mod)
  59         {
  60                 Reset();
  61         }
  62
  63         void Reset()
  64         {
  65                 if (sasl_target == "*")
  66                 {
  67                         online = true;
  68                         return;
  69                 }
  70
  71                 online = false;
  72
  73                 ProtocolInterface::ServerList servers;
  74                 ServerInstance->PI->GetServerList(servers);
  75                 for (ProtocolInterface::ServerList::const_iterator i = servers.begin(); i != servers.end(); ++i)
  76                 {
  77                         const ProtocolInterface::ServerInfo& server = *i;
  78                         if (InspIRCd::Match(server.servername, sasl_target))
  79                         {
  80                                 online = true;
  81                                 break;
  82                         }
  83                 }
  84         }
  85
  86         bool IsOnline() const { return online; }
  87 };
  88
  89 class SASLCap : public Cap::Capability
  90 {
  91         std::string mechlist;
  92         const ServerTracker& servertracker;
  93
  94         bool OnRequest(LocalUser* user, bool adding) CXX11_OVERRIDE
  95         {
  96                 // Requesting this cap is allowed anytime
  97                 if (adding)
  98                         return true;
  99
 100                 // But removing it can only be done when unregistered
 101                 return (user->registered != REG_ALL);
 102         }
 103
 104         bool OnList(LocalUser* user) CXX11_OVERRIDE
 105         {
 106                 return servertracker.IsOnline();
 107         }
 108
 109         const std::string* GetValue(LocalUser* user) const CXX11_OVERRIDE
 110         {
 111                 return &mechlist;
 112         }
 113
 114  public:
 115         SASLCap(Module* mod, const ServerTracker& tracker)
 116                 : Cap::Capability(mod, "sasl")
 117                 , servertracker(tracker)
 118         {
 119         }
 120
 121         void SetMechlist(const std::string& newmechlist)
 122         {
 123                 if (mechlist == newmechlist)
 124                         return;
 125
 126                 mechlist = newmechlist;
 127                 NotifyValueChange();
 128         }
 129 };
 130
 131 enum SaslState { SASL_INIT, SASL_COMM, SASL_DONE };
 132 enum SaslResult { SASL_OK, SASL_FAIL, SASL_ABORT };
 133
 134 static Events::ModuleEventProvider* saslevprov;
 135
 136 static void SendSASL(const parameterlist& params)
 137 {
 138         if (!ServerInstance->PI->SendEncapsulatedData(sasl_target, "SASL", params))
 139         {
 140                 FOREACH_MOD_CUSTOM(*saslevprov, SASLEventListener, OnSASLAuth, (params));
 141         }
 142 }
 143
 144 /**
 145  * Tracks SASL authentication state like charybdis does. --nenolod
 146  */
 147 class SaslAuthenticator
 148 {
 149  private:
 150         std::string agent;
 151         User *user;
 152         SaslState state;
 153         SaslResult result;
 154         bool state_announced;
 155
 156  public:
 157         SaslAuthenticator(User* user_, const std::string& method)
 158                 : user(user_), state(SASL_INIT), state_announced(false)
 159         {
 160                 parameterlist params;
 161                 params.push_back(user->uuid);
 162                 params.push_back("*");
 163                 params.push_back("S");
 164                 params.push_back(method);
 165
 166                 LocalUser* localuser = IS_LOCAL(user);
 167                 if (method == "EXTERNAL" && localuser)
 168                 {
 169                         std::string fp = SSLClientCert::GetFingerprint(&localuser->eh);
 170
 171                         if (fp.size())
 172                                 params.push_back(fp);
 173                 }
 174
 175                 SendSASL(params);
 176         }
 177
 178         SaslResult GetSaslResult(const std::string &result_)
 179         {
 180                 if (result_ == "F")
 181                         return SASL_FAIL;
 182
 183                 if (result_ == "A")
 184                         return SASL_ABORT;
 185
 186                 return SASL_OK;
 187         }
 188
 189         /* checks for and deals with a state change. */
 190         SaslState ProcessInboundMessage(const std::vector<std::string> &msg)
 191         {
 192                 switch (this->state)
 193                 {
 194                  case SASL_INIT:
 195                         this->agent = msg[0];
 196                         this->state = SASL_COMM;
 197                         /* fall through */
 198                  case SASL_COMM:
 199                         if (msg[0] != this->agent)
 200                                 return this->state;
 201
 202                         if (msg.size() < 4)
 203                                 return this->state;
 204
 205                         if (msg[2] == "C")
 206                                 this->user->Write("AUTHENTICATE %s", msg[3].c_str());
 207                         else if (msg[2] == "D")
 208                         {
 209                                 this->state = SASL_DONE;
 210                                 this->result = this->GetSaslResult(msg[3]);
 211                         }
 212                         else if (msg[2] == "M")
 213                                 this->user->WriteNumeric(908, msg[3], "are available SASL mechanisms");
 214                         else
 215                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Services sent an unknown SASL message \"%s\" \"%s\"", msg[2].c_str(), msg[3].c_str());
 216
 217                         break;
 218                  case SASL_DONE:
 219                         break;
 220                  default:
 221                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "WTF: SaslState is not a known state (%d)", this->state);
 222                         break;
 223                 }
 224
 225                 return this->state;
 226         }
 227
 228         void Abort(void)
 229         {
 230                 this->state = SASL_DONE;
 231                 this->result = SASL_ABORT;
 232         }
 233
 234         bool SendClientMessage(const std::vector<std::string>& parameters)
 235         {
 236                 if (this->state != SASL_COMM)
 237                         return true;
 238
 239                 parameterlist params;
 240                 params.push_back(this->user->uuid);
 241                 params.push_back(this->agent);
 242                 params.push_back("C");
 243
 244                 params.insert(params.end(), parameters.begin(), parameters.end());
 245
 246                 SendSASL(params);
 247
 248                 if (parameters[0].c_str()[0] == '*')
 249                 {
 250                         this->Abort();
 251                         return false;
 252                 }
 253
 254                 return true;
 255         }
 256
 257         void AnnounceState(void)
 258         {
 259                 if (this->state_announced)
 260                         return;
 261
 262                 switch (this->result)
 263                 {
 264                  case SASL_OK:
 265                         this->user->WriteNumeric(903, "SASL authentication successful");
 266                         break;
 267                  case SASL_ABORT:
 268                         this->user->WriteNumeric(906, "SASL authentication aborted");
 269                         break;
 270                  case SASL_FAIL:
 271                         this->user->WriteNumeric(904, "SASL authentication failed");
 272                         break;
 273                  default:
 274                         break;
 275                 }
 276
 277                 this->state_announced = true;
 278         }
 279 };
 280
 281 class CommandAuthenticate : public Command
 282 {
 283  public:
 284         SimpleExtItem<SaslAuthenticator>& authExt;
 285         Cap::Capability& cap;
 286         CommandAuthenticate(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext, Cap::Capability& Cap)
 287                 : Command(Creator, "AUTHENTICATE", 1), authExt(ext), cap(Cap)
 288         {
 289                 works_before_reg = true;
 290         }
 291
 292         CmdResult Handle (const std::vector<std::string>& parameters, User *user)
 293         {
 294                 {
 295                         if (!cap.get(user))
 296                                 return CMD_FAILURE;
 297
 298                         SaslAuthenticator *sasl = authExt.get(user);
 299                         if (!sasl)
 300                                 authExt.set(user, new SaslAuthenticator(user, parameters[0]));
 301                         else if (sasl->SendClientMessage(parameters) == false)  // IAL abort extension --nenolod
 302                         {
 303                                 sasl->AnnounceState();
 304                                 authExt.unset(user);
 305                         }
 306                 }
 307                 return CMD_FAILURE;
 308         }
 309 };
 310
 311 class CommandSASL : public Command
 312 {
 313  public:
 314         SimpleExtItem<SaslAuthenticator>& authExt;
 315         CommandSASL(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext) : Command(Creator, "SASL", 2), authExt(ext)
 316         {
 317                 this->flags_needed = FLAG_SERVERONLY; // should not be called by users
 318         }
 319
 320         CmdResult Handle(const std::vector<std::string>& parameters, User *user)
 321         {
 322                 User* target = ServerInstance->FindUUID(parameters[1]);
 323                 if (!target)
 324                 {
 325                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "User not found in sasl ENCAP event: %s", parameters[1].c_str());
 326                         return CMD_FAILURE;
 327                 }
 328
 329                 SaslAuthenticator *sasl = authExt.get(target);
 330                 if (!sasl)
 331                         return CMD_FAILURE;
 332
 333                 SaslState state = sasl->ProcessInboundMessage(parameters);
 334                 if (state == SASL_DONE)
 335                 {
 336                         sasl->AnnounceState();
 337                         authExt.unset(target);
 338                 }
 339                 return CMD_SUCCESS;
 340         }
 341
 342         RouteDescriptor GetRouting(User* user, const std::vector<std::string>& parameters)
 343         {
 344                 return ROUTE_BROADCAST;
 345         }
 346 };
 347
 348 class ModuleSASL : public Module
 349 {
 350         SimpleExtItem<SaslAuthenticator> authExt;
 351         ServerTracker servertracker;
 352         SASLCap cap;
 353         CommandAuthenticate auth;
 354         CommandSASL sasl;
 355         Events::ModuleEventProvider sasleventprov;
 356
 357  public:
 358         ModuleSASL()
 359                 : authExt("sasl_auth", ExtensionItem::EXT_USER, this)
 360                 , servertracker(this)
 361                 , cap(this, servertracker)
 362                 , auth(this, authExt, cap)
 363                 , sasl(this, authExt)
 364                 , sasleventprov(this, "event/sasl")
 365         {
 366                 saslevprov = &sasleventprov;
 367         }
 368
 369         void init() CXX11_OVERRIDE
 370         {
 371                 if (!ServerInstance->Modules->Find("m_services_account.so") || !ServerInstance->Modules->Find("m_cap.so"))
 372                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "WARNING: m_services_account.so and m_cap.so are not loaded! m_sasl.so will NOT function correctly until these two modules are loaded!");
 373         }
 374
 375         void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
 376         {
 377                 sasl_target = ServerInstance->Config->ConfValue("sasl")->getString("target", "*");
 378                 servertracker.Reset();
 379         }
 380
 381         ModResult OnUserRegister(LocalUser *user) CXX11_OVERRIDE
 382         {
 383                 SaslAuthenticator *sasl_ = authExt.get(user);
 384                 if (sasl_)
 385                 {
 386                         sasl_->Abort();
 387                         authExt.unset(user);
 388                 }
 389
 390                 return MOD_RES_PASSTHRU;
 391         }
 392
 393         void OnDecodeMetaData(Extensible* target, const std::string& extname, const std::string& extdata) CXX11_OVERRIDE
 394         {
 395                 if ((target == NULL) && (extname == "saslmechlist"))
 396                         cap.SetMechlist(extdata);
 397         }
 398
 399         Version GetVersion() CXX11_OVERRIDE
 400         {
 401                 return Version("Provides support for IRC Authentication Layer (aka: SASL) via AUTHENTICATE.", VF_VENDOR);
 402         }
 403 };
 404
 405 MODULE_INIT(ModuleSASL)