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(LocalUser* user, const std::string& agent, char mode, const parameterlist& parameters)
 147 {
 148         parameterlist params(parameters.size() + 3);
 149         params.push_back(user->uuid);
 150         params.push_back(agent);
 151         params.push_back(ConvToStr(mode));
 152         params.insert(params.end(), parameters.begin(), parameters.end());
 153
 154         if (!ServerInstance->PI->SendEncapsulatedData(sasl_target, "SASL", params))
 155         {
 156                 FOREACH_MOD_CUSTOM(*saslevprov, SASLEventListener, OnSASLAuth, (params));
 157         }
 158 }
 159
 160 /**
 161  * Tracks SASL authentication state like charybdis does. --nenolod
 162  */
 163 class SaslAuthenticator
 164 {
 165  private:
 166         std::string agent;
 167         LocalUser* user;
 168         SaslState state;
 169         SaslResult result;
 170         bool state_announced;
 171
 172         void SendHostIP()
 173         {
 174                 parameterlist params;
 175                 params.push_back(user->host);
 176                 params.push_back(user->GetIPString());
 177
 178                 SendSASL(user, "*", 'H', params);
 179         }
 180
 181  public:
 182         SaslAuthenticator(LocalUser* user_, const std::string& method)
 183                 : user(user_), state(SASL_INIT), state_announced(false)
 184         {
 185                 SendHostIP();
 186
 187                 parameterlist params;
 188                 params.push_back(method);
 189
 190                 const std::string fp = SSLClientCert::GetFingerprint(&user->eh);
 191                 if (fp.size())
 192                         params.push_back(fp);
 193
 194                 SendSASL(user, "*", 'S', params);
 195         }
 196
 197         SaslResult GetSaslResult(const std::string &result_)
 198         {
 199                 if (result_ == "F")
 200                         return SASL_FAIL;
 201
 202                 if (result_ == "A")
 203                         return SASL_ABORT;
 204
 205                 return SASL_OK;
 206         }
 207
 208         /* checks for and deals with a state change. */
 209         SaslState ProcessInboundMessage(const std::vector<std::string> &msg)
 210         {
 211                 switch (this->state)
 212                 {
 213                  case SASL_INIT:
 214                         this->agent = msg[0];
 215                         this->state = SASL_COMM;
 216                         /* fall through */
 217                  case SASL_COMM:
 218                         if (msg[0] != this->agent)
 219                                 return this->state;
 220
 221                         if (msg.size() < 4)
 222                                 return this->state;
 223
 224                         if (msg[2] == "C")
 225                                 this->user->Write("AUTHENTICATE %s", msg[3].c_str());
 226                         else if (msg[2] == "D")
 227                         {
 228                                 this->state = SASL_DONE;
 229                                 this->result = this->GetSaslResult(msg[3]);
 230                         }
 231                         else if (msg[2] == "M")
 232                                 this->user->WriteNumeric(RPL_SASLMECHS, msg[3], "are available SASL mechanisms");
 233                         else
 234                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Services sent an unknown SASL message \"%s\" \"%s\"", msg[2].c_str(), msg[3].c_str());
 235
 236                         break;
 237                  case SASL_DONE:
 238                         break;
 239                  default:
 240                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "WTF: SaslState is not a known state (%d)", this->state);
 241                         break;
 242                 }
 243
 244                 return this->state;
 245         }
 246
 247         bool SendClientMessage(const std::vector<std::string>& parameters)
 248         {
 249                 if (this->state != SASL_COMM)
 250                         return true;
 251
 252                 SendSASL(this->user, this->agent, 'C', parameters);
 253
 254                 if (parameters[0].c_str()[0] == '*')
 255                 {
 256                         this->state = SASL_DONE;
 257                         this->result = SASL_ABORT;
 258                         return false;
 259                 }
 260
 261                 return true;
 262         }
 263
 264         void AnnounceState(void)
 265         {
 266                 if (this->state_announced)
 267                         return;
 268
 269                 switch (this->result)
 270                 {
 271                  case SASL_OK:
 272                         this->user->WriteNumeric(RPL_SASLSUCCESS, "SASL authentication successful");
 273                         break;
 274                  case SASL_ABORT:
 275                         this->user->WriteNumeric(ERR_SASLABORTED, "SASL authentication aborted");
 276                         break;
 277                  case SASL_FAIL:
 278                         this->user->WriteNumeric(ERR_SASLFAIL, "SASL authentication failed");
 279                         break;
 280                  default:
 281                         break;
 282                 }
 283
 284                 this->state_announced = true;
 285         }
 286 };
 287
 288 class CommandAuthenticate : public SplitCommand
 289 {
 290  private:
 291          // The maximum length of an AUTHENTICATE request.
 292          static const size_t MAX_AUTHENTICATE_SIZE = 400;
 293
 294  public:
 295         SimpleExtItem<SaslAuthenticator>& authExt;
 296         Cap::Capability& cap;
 297         CommandAuthenticate(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext, Cap::Capability& Cap)
 298                 : SplitCommand(Creator, "AUTHENTICATE", 1)
 299                 , authExt(ext)
 300                 , cap(Cap)
 301         {
 302                 works_before_reg = true;
 303                 allow_empty_last_param = false;
 304         }
 305
 306         CmdResult HandleLocal(const std::vector<std::string>& parameters, LocalUser* user)
 307         {
 308                 {
 309                         if (!cap.get(user))
 310                                 return CMD_FAILURE;
 311
 312                         if (parameters[0].find(' ') != std::string::npos || parameters[0][0] == ':')
 313                                 return CMD_FAILURE;
 314
 315                         if (parameters[0].length() > MAX_AUTHENTICATE_SIZE)
 316                         {
 317                                 user->WriteNumeric(ERR_SASLTOOLONG, "SASL message too long");
 318                                 return CMD_FAILURE;
 319                         }
 320
 321                         SaslAuthenticator *sasl = authExt.get(user);
 322                         if (!sasl)
 323                                 authExt.set(user, new SaslAuthenticator(user, parameters[0]));
 324                         else if (sasl->SendClientMessage(parameters) == false)  // IAL abort extension --nenolod
 325                         {
 326                                 sasl->AnnounceState();
 327                                 authExt.unset(user);
 328                         }
 329                 }
 330                 return CMD_FAILURE;
 331         }
 332 };
 333
 334 class CommandSASL : public Command
 335 {
 336  public:
 337         SimpleExtItem<SaslAuthenticator>& authExt;
 338         CommandSASL(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext) : Command(Creator, "SASL", 2), authExt(ext)
 339         {
 340                 this->flags_needed = FLAG_SERVERONLY; // should not be called by users
 341         }
 342
 343         CmdResult Handle(const std::vector<std::string>& parameters, User *user)
 344         {
 345                 User* target = ServerInstance->FindUUID(parameters[1]);
 346                 if (!target)
 347                 {
 348                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "User not found in sasl ENCAP event: %s", parameters[1].c_str());
 349                         return CMD_FAILURE;
 350                 }
 351
 352                 SaslAuthenticator *sasl = authExt.get(target);
 353                 if (!sasl)
 354                         return CMD_FAILURE;
 355
 356                 SaslState state = sasl->ProcessInboundMessage(parameters);
 357                 if (state == SASL_DONE)
 358                 {
 359                         sasl->AnnounceState();
 360                         authExt.unset(target);
 361                 }
 362                 return CMD_SUCCESS;
 363         }
 364
 365         RouteDescriptor GetRouting(User* user, const std::vector<std::string>& parameters)
 366         {
 367                 return ROUTE_BROADCAST;
 368         }
 369 };
 370
 371 class ModuleSASL : public Module
 372 {
 373         SimpleExtItem<SaslAuthenticator> authExt;
 374         ServerTracker servertracker;
 375         SASLCap cap;
 376         CommandAuthenticate auth;
 377         CommandSASL sasl;
 378         Events::ModuleEventProvider sasleventprov;
 379
 380  public:
 381         ModuleSASL()
 382                 : authExt("sasl_auth", ExtensionItem::EXT_USER, this)
 383                 , servertracker(this)
 384                 , cap(this, servertracker)
 385                 , auth(this, authExt, cap)
 386                 , sasl(this, authExt)
 387                 , sasleventprov(this, "event/sasl")
 388         {
 389                 saslevprov = &sasleventprov;
 390         }
 391
 392         void init() CXX11_OVERRIDE
 393         {
 394                 if (!ServerInstance->Modules->Find("m_services_account.so") || !ServerInstance->Modules->Find("m_cap.so"))
 395                         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!");
 396         }
 397
 398         void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
 399         {
 400                 sasl_target = ServerInstance->Config->ConfValue("sasl")->getString("target", "*");
 401                 servertracker.Reset();
 402         }
 403
 404         void OnDecodeMetaData(Extensible* target, const std::string& extname, const std::string& extdata) CXX11_OVERRIDE
 405         {
 406                 if ((target == NULL) && (extname == "saslmechlist"))
 407                         cap.SetMechlist(extdata);
 408         }
 409
 410         Version GetVersion() CXX11_OVERRIDE
 411         {
 412                 return Version("Provides support for IRC Authentication Layer (aka: SASL) via AUTHENTICATE.", VF_VENDOR);
 413         }
 414 };
 415
 416 MODULE_INIT(ModuleSASL)