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 enum
  29 {
  30         // From IRCv3 sasl-3.1
  31         RPL_SASLSUCCESS = 903,
  32         ERR_SASLFAIL = 904,
  33         ERR_SASLTOOLONG = 905,
  34         ERR_SASLABORTED = 906,
  35         RPL_SASLMECHS = 908
  36 };
  37
  38 static std::string sasl_target;
  39
  40 class ServerTracker : public SpanningTreeEventListener
  41 {
  42         bool online;
  43
  44         void Update(const Server* server, bool linked)
  45         {
  46                 if (sasl_target == "*")
  47                         return;
  48
  49                 if (InspIRCd::Match(server->GetName(), sasl_target))
  50                 {
  51                         ServerInstance->Logs->Log(MODNAME, LOG_VERBOSE, "SASL target server \"%s\" %s", sasl_target.c_str(), (linked ? "came online" : "went offline"));
  52                         online = linked;
  53                 }
  54         }
  55
  56         void OnServerLink(const Server* server) CXX11_OVERRIDE
  57         {
  58                 Update(server, true);
  59         }
  60
  61         void OnServerSplit(const Server* server) CXX11_OVERRIDE
  62         {
  63                 Update(server, false);
  64         }
  65
  66  public:
  67         ServerTracker(Module* mod)
  68                 : SpanningTreeEventListener(mod)
  69         {
  70                 Reset();
  71         }
  72
  73         void Reset()
  74         {
  75                 if (sasl_target == "*")
  76                 {
  77                         online = true;
  78                         return;
  79                 }
  80
  81                 online = false;
  82
  83                 ProtocolInterface::ServerList servers;
  84                 ServerInstance->PI->GetServerList(servers);
  85                 for (ProtocolInterface::ServerList::const_iterator i = servers.begin(); i != servers.end(); ++i)
  86                 {
  87                         const ProtocolInterface::ServerInfo& server = *i;
  88                         if (InspIRCd::Match(server.servername, sasl_target))
  89                         {
  90                                 online = true;
  91                                 break;
  92                         }
  93                 }
  94         }
  95
  96         bool IsOnline() const { return online; }
  97 };
  98
  99 class SASLCap : public Cap::Capability
 100 {
 101         std::string mechlist;
 102         const ServerTracker& servertracker;
 103
 104         bool OnRequest(LocalUser* user, bool adding) CXX11_OVERRIDE
 105         {
 106                 // Requesting this cap is allowed anytime
 107                 if (adding)
 108                         return true;
 109
 110                 // But removing it can only be done when unregistered
 111                 return (user->registered != REG_ALL);
 112         }
 113
 114         bool OnList(LocalUser* user) CXX11_OVERRIDE
 115         {
 116                 return servertracker.IsOnline();
 117         }
 118
 119         const std::string* GetValue(LocalUser* user) const CXX11_OVERRIDE
 120         {
 121                 return &mechlist;
 122         }
 123
 124  public:
 125         SASLCap(Module* mod, const ServerTracker& tracker)
 126                 : Cap::Capability(mod, "sasl")
 127                 , servertracker(tracker)
 128         {
 129         }
 130
 131         void SetMechlist(const std::string& newmechlist)
 132         {
 133                 if (mechlist == newmechlist)
 134                         return;
 135
 136                 mechlist = newmechlist;
 137                 NotifyValueChange();
 138         }
 139 };
 140
 141 enum SaslState { SASL_INIT, SASL_COMM, SASL_DONE };
 142 enum SaslResult { SASL_OK, SASL_FAIL, SASL_ABORT };
 143
 144 static Events::ModuleEventProvider* saslevprov;
 145
 146 static void SendSASL(const parameterlist& params)
 147 {
 148         if (!ServerInstance->PI->SendEncapsulatedData(sasl_target, "SASL", params))
 149         {
 150                 FOREACH_MOD_CUSTOM(*saslevprov, SASLEventListener, OnSASLAuth, (params));
 151         }
 152 }
 153
 154 /**
 155  * Tracks SASL authentication state like charybdis does. --nenolod
 156  */
 157 class SaslAuthenticator
 158 {
 159  private:
 160         std::string agent;
 161         LocalUser* user;
 162         SaslState state;
 163         SaslResult result;
 164         bool state_announced;
 165
 166         void SendHostIP()
 167         {
 168                 parameterlist params;
 169                 params.push_back(sasl_target);
 170                 params.push_back("SASL");
 171                 params.push_back(user->uuid);
 172                 params.push_back("*");
 173                 params.push_back("H");
 174                 params.push_back(user->host);
 175                 params.push_back(user->GetIPString());
 176
 177                 SendSASL(params);
 178         }
 179
 180  public:
 181         SaslAuthenticator(LocalUser* user_, const std::string& method)
 182                 : user(user_), state(SASL_INIT), state_announced(false)
 183         {
 184                 SendHostIP();
 185
 186                 parameterlist params;
 187                 params.push_back(user->uuid);
 188                 params.push_back("*");
 189                 params.push_back("S");
 190                 params.push_back(method);
 191
 192                 const std::string fp = SSLClientCert::GetFingerprint(&user->eh);
 193                 if (fp.size())
 194                         params.push_back(fp);
 195
 196                 SendSASL(params);
 197         }
 198
 199         SaslResult GetSaslResult(const std::string &result_)
 200         {
 201                 if (result_ == "F")
 202                         return SASL_FAIL;
 203
 204                 if (result_ == "A")
 205                         return SASL_ABORT;
 206
 207                 return SASL_OK;
 208         }
 209
 210         /* checks for and deals with a state change. */
 211         SaslState ProcessInboundMessage(const std::vector<std::string> &msg)
 212         {
 213                 switch (this->state)
 214                 {
 215                  case SASL_INIT:
 216                         this->agent = msg[0];
 217                         this->state = SASL_COMM;
 218                         /* fall through */
 219                  case SASL_COMM:
 220                         if (msg[0] != this->agent)
 221                                 return this->state;
 222
 223                         if (msg.size() < 4)
 224                                 return this->state;
 225
 226                         if (msg[2] == "C")
 227                                 this->user->Write("AUTHENTICATE %s", msg[3].c_str());
 228                         else if (msg[2] == "D")
 229                         {
 230                                 this->state = SASL_DONE;
 231                                 this->result = this->GetSaslResult(msg[3]);
 232                         }
 233                         else if (msg[2] == "M")
 234                                 this->user->WriteNumeric(RPL_SASLMECHS, msg[3], "are available SASL mechanisms");
 235                         else
 236                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Services sent an unknown SASL message \"%s\" \"%s\"", msg[2].c_str(), msg[3].c_str());
 237
 238                         break;
 239                  case SASL_DONE:
 240                         break;
 241                  default:
 242                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "WTF: SaslState is not a known state (%d)", this->state);
 243                         break;
 244                 }
 245
 246                 return this->state;
 247         }
 248
 249         bool SendClientMessage(const std::vector<std::string>& parameters)
 250         {
 251                 if (this->state != SASL_COMM)
 252                         return true;
 253
 254                 parameterlist params;
 255                 params.push_back(this->user->uuid);
 256                 params.push_back(this->agent);
 257                 params.push_back("C");
 258
 259                 params.insert(params.end(), parameters.begin(), parameters.end());
 260
 261                 SendSASL(params);
 262
 263                 if (parameters[0].c_str()[0] == '*')
 264                 {
 265                         this->state = SASL_DONE;
 266                         this->result = SASL_ABORT;
 267                         return false;
 268                 }
 269
 270                 return true;
 271         }
 272
 273         void AnnounceState(void)
 274         {
 275                 if (this->state_announced)
 276                         return;
 277
 278                 switch (this->result)
 279                 {
 280                  case SASL_OK:
 281                         this->user->WriteNumeric(RPL_SASLSUCCESS, "SASL authentication successful");
 282                         break;
 283                  case SASL_ABORT:
 284                         this->user->WriteNumeric(ERR_SASLABORTED, "SASL authentication aborted");
 285                         break;
 286                  case SASL_FAIL:
 287                         this->user->WriteNumeric(ERR_SASLFAIL, "SASL authentication failed");
 288                         break;
 289                  default:
 290                         break;
 291                 }
 292
 293                 this->state_announced = true;
 294         }
 295 };
 296
 297 class CommandAuthenticate : public SplitCommand
 298 {
 299  private:
 300          // The maximum length of an AUTHENTICATE request.
 301          static const size_t MAX_AUTHENTICATE_SIZE = 400;
 302
 303  public:
 304         SimpleExtItem<SaslAuthenticator>& authExt;
 305         Cap::Capability& cap;
 306         CommandAuthenticate(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext, Cap::Capability& Cap)
 307                 : SplitCommand(Creator, "AUTHENTICATE", 1)
 308                 , authExt(ext)
 309                 , cap(Cap)
 310         {
 311                 works_before_reg = true;
 312                 allow_empty_last_param = false;
 313         }
 314
 315         CmdResult HandleLocal(const std::vector<std::string>& parameters, LocalUser* user)
 316         {
 317                 {
 318                         if (!cap.get(user))
 319                                 return CMD_FAILURE;
 320
 321                         if (parameters[0].find(' ') != std::string::npos || parameters[0][0] == ':')
 322                                 return CMD_FAILURE;
 323
 324                         if (parameters[0].length() > MAX_AUTHENTICATE_SIZE)
 325                         {
 326                                 user->WriteNumeric(ERR_SASLTOOLONG, "SASL message too long");
 327                                 return CMD_FAILURE;
 328                         }
 329
 330                         SaslAuthenticator *sasl = authExt.get(user);
 331                         if (!sasl)
 332                                 authExt.set(user, new SaslAuthenticator(user, parameters[0]));
 333                         else if (sasl->SendClientMessage(parameters) == false)  // IAL abort extension --nenolod
 334                         {
 335                                 sasl->AnnounceState();
 336                                 authExt.unset(user);
 337                         }
 338                 }
 339                 return CMD_FAILURE;
 340         }
 341 };
 342
 343 class CommandSASL : public Command
 344 {
 345  public:
 346         SimpleExtItem<SaslAuthenticator>& authExt;
 347         CommandSASL(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext) : Command(Creator, "SASL", 2), authExt(ext)
 348         {
 349                 this->flags_needed = FLAG_SERVERONLY; // should not be called by users
 350         }
 351
 352         CmdResult Handle(const std::vector<std::string>& parameters, User *user)
 353         {
 354                 User* target = ServerInstance->FindUUID(parameters[1]);
 355                 if (!target)
 356                 {
 357                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "User not found in sasl ENCAP event: %s", parameters[1].c_str());
 358                         return CMD_FAILURE;
 359                 }
 360
 361                 SaslAuthenticator *sasl = authExt.get(target);
 362                 if (!sasl)
 363                         return CMD_FAILURE;
 364
 365                 SaslState state = sasl->ProcessInboundMessage(parameters);
 366                 if (state == SASL_DONE)
 367                 {
 368                         sasl->AnnounceState();
 369                         authExt.unset(target);
 370                 }
 371                 return CMD_SUCCESS;
 372         }
 373
 374         RouteDescriptor GetRouting(User* user, const std::vector<std::string>& parameters)
 375         {
 376                 return ROUTE_BROADCAST;
 377         }
 378 };
 379
 380 class ModuleSASL : public Module
 381 {
 382         SimpleExtItem<SaslAuthenticator> authExt;
 383         ServerTracker servertracker;
 384         SASLCap cap;
 385         CommandAuthenticate auth;
 386         CommandSASL sasl;
 387         Events::ModuleEventProvider sasleventprov;
 388
 389  public:
 390         ModuleSASL()
 391                 : authExt("sasl_auth", ExtensionItem::EXT_USER, this)
 392                 , servertracker(this)
 393                 , cap(this, servertracker)
 394                 , auth(this, authExt, cap)
 395                 , sasl(this, authExt)
 396                 , sasleventprov(this, "event/sasl")
 397         {
 398                 saslevprov = &sasleventprov;
 399         }
 400
 401         void init() CXX11_OVERRIDE
 402         {
 403                 if (!ServerInstance->Modules->Find("m_services_account.so") || !ServerInstance->Modules->Find("m_cap.so"))
 404                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "WARNING: m_services_account and m_cap are not loaded! m_sasl will NOT function correctly until these two modules are loaded!");
 405         }
 406
 407         void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
 408         {
 409                 sasl_target = ServerInstance->Config->ConfValue("sasl")->getString("target", "*");
 410                 servertracker.Reset();
 411         }
 412
 413         void OnDecodeMetaData(Extensible* target, const std::string& extname, const std::string& extdata) CXX11_OVERRIDE
 414         {
 415                 if ((target == NULL) && (extname == "saslmechlist"))
 416                         cap.SetMechlist(extdata);
 417         }
 418
 419         Version GetVersion() CXX11_OVERRIDE
 420         {
 421                 return Version("Provides support for IRC Authentication Layer (aka: SASL) via AUTHENTICATE.", VF_VENDOR);
 422         }
 423 };
 424
 425 MODULE_INIT(ModuleSASL)