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