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 "m_cap.h"
  23 #include "account.h"
  24 #include "sasl.h"
  25 #include "ssl.h"
  26
  27 /* $ModDesc: Provides support for IRC Authentication Layer (aka: atheme SASL) via AUTHENTICATE. */
  28
  29 enum SaslState { SASL_INIT, SASL_COMM, SASL_DONE };
  30 enum SaslResult { SASL_OK, SASL_FAIL, SASL_ABORT };
  31
  32 static std::string sasl_target = "*";
  33
  34 static void SendSASL(const parameterlist& params)
  35 {
  36         if (!ServerInstance->PI->SendEncapsulatedData(params))
  37         {
  38                 User* u = ServerInstance->FindUUID(params[2]);
  39                 if (u)
  40                         u->WriteNumeric(904, "%s :SASL authentication failed", u->nick.c_str());
  41
  42                 SASLFallback(NULL, params);
  43         }
  44 }
  45
  46 /**
  47  * Tracks SASL authentication state like charybdis does. --nenolod
  48  */
  49 class SaslAuthenticator
  50 {
  51  private:
  52         std::string agent;
  53         User *user;
  54         SaslState state;
  55         SaslResult result;
  56         bool state_announced;
  57
  58         /* taken from m_services_account */
  59         static bool ReadCGIIRCExt(const char* extname, User* user, std::string& out)
  60         {
  61                 ExtensionItem* wiext = ServerInstance->Extensions.GetItem(extname);
  62                 if (!wiext)
  63                         return false;
  64
  65                 if (wiext->creator->ModuleSourceFile != "m_cgiirc.so")
  66                         return false;
  67
  68                 StringExtItem* stringext = static_cast<StringExtItem*>(wiext);
  69                 std::string* addr = stringext->get(user);
  70                 if (!addr)
  71                         return false;
  72
  73                 out = *addr;
  74                 return true;
  75         }
  76
  77
  78         void SendHostIP()
  79         {
  80                 std::string host, ip;
  81
  82                 if (!ReadCGIIRCExt("cgiirc_webirc_hostname", user, host))
  83                 {
  84                         host = user->host;
  85                 }
  86                 if (!ReadCGIIRCExt("cgiirc_webirc_ip", user, ip))
  87                 {
  88                         ip = user->GetIPString();
  89                 }
  90                 else
  91                 {
  92                         /* IP addresses starting with a : on irc are a Bad Thing (tm) */
  93                         if (ip.c_str()[0] == ':')
  94                                 ip.insert(ip.begin(),1,'0');
  95                 }
  96
  97                 parameterlist params;
  98                 params.push_back(sasl_target);
  99                 params.push_back("SASL");
 100                 params.push_back(user->uuid);
 101                 params.push_back("*");
 102                 params.push_back("H");
 103                 params.push_back(host);
 104                 params.push_back(ip);
 105
 106                 LocalUser* lu = IS_LOCAL(user);
 107                 if (lu)
 108                 {
 109                         // NOTE: SaslAuthenticator instances are only created for local
 110                         // users so this parameter will always be appended.
 111                         SocketCertificateRequest req(&lu->eh, ServerInstance->Modules->Find("m_sasl.so"));
 112                         params.push_back(req.cert ? "S" : "P");
 113                 }
 114
 115                 SendSASL(params);
 116         }
 117
 118  public:
 119         SaslAuthenticator(User* user_, const std::string& method)
 120                 : user(user_), state(SASL_INIT), state_announced(false)
 121         {
 122                 SendHostIP();
 123
 124                 parameterlist params;
 125                 params.push_back(sasl_target);
 126                 params.push_back("SASL");
 127                 params.push_back(user->uuid);
 128                 params.push_back("*");
 129                 params.push_back("S");
 130                 params.push_back(method);
 131
 132                 if (method == "EXTERNAL" && IS_LOCAL(user_))
 133                 {
 134                         SocketCertificateRequest req(&((LocalUser*)user_)->eh, ServerInstance->Modules->Find("m_sasl.so"));
 135                         std::string fp = req.GetFingerprint();
 136
 137                         if (fp.size())
 138                                 params.push_back(fp);
 139                 }
 140
 141                 SendSASL(params);
 142         }
 143
 144         SaslResult GetSaslResult(const std::string &result_)
 145         {
 146                 if (result_ == "F")
 147                         return SASL_FAIL;
 148
 149                 if (result_ == "A")
 150                         return SASL_ABORT;
 151
 152                 return SASL_OK;
 153         }
 154
 155         /* checks for and deals with a state change. */
 156         SaslState ProcessInboundMessage(const std::vector<std::string> &msg)
 157         {
 158                 switch (this->state)
 159                 {
 160                  case SASL_INIT:
 161                         this->agent = msg[0];
 162                         this->state = SASL_COMM;
 163                         /* fall through */
 164                  case SASL_COMM:
 165                         if (msg[0] != this->agent)
 166                                 return this->state;
 167
 168                         if (msg.size() < 4)
 169                                 return this->state;
 170
 171                         if (msg[2] == "C")
 172                                 this->user->Write("AUTHENTICATE %s", msg[3].c_str());
 173                         else if (msg[2] == "D")
 174                         {
 175                                 this->state = SASL_DONE;
 176                                 this->result = this->GetSaslResult(msg[3]);
 177                         }
 178                         else if (msg[2] == "M")
 179                                 this->user->WriteNumeric(908, "%s %s :are available SASL mechanisms", this->user->nick.c_str(), msg[3].c_str());
 180                         else
 181                                 ServerInstance->Logs->Log("m_sasl", DEFAULT, "Services sent an unknown SASL message \"%s\" \"%s\"", msg[2].c_str(), msg[3].c_str());
 182
 183                         break;
 184                  case SASL_DONE:
 185                         break;
 186                  default:
 187                         ServerInstance->Logs->Log("m_sasl", DEFAULT, "WTF: SaslState is not a known state (%d)", this->state);
 188                         break;
 189                 }
 190
 191                 return this->state;
 192         }
 193
 194         void Abort(void)
 195         {
 196                 this->state = SASL_DONE;
 197                 this->result = SASL_ABORT;
 198         }
 199
 200         bool SendClientMessage(const std::vector<std::string>& parameters)
 201         {
 202                 if (this->state != SASL_COMM)
 203                         return true;
 204
 205                 parameterlist params;
 206                 params.push_back(sasl_target);
 207                 params.push_back("SASL");
 208                 params.push_back(this->user->uuid);
 209                 params.push_back(this->agent);
 210                 params.push_back("C");
 211
 212                 params.insert(params.end(), parameters.begin(), parameters.end());
 213
 214                 SendSASL(params);
 215
 216                 if (parameters[0].c_str()[0] == '*')
 217                 {
 218                         this->Abort();
 219                         return false;
 220                 }
 221
 222                 return true;
 223         }
 224
 225         void AnnounceState(void)
 226         {
 227                 if (this->state_announced)
 228                         return;
 229
 230                 switch (this->result)
 231                 {
 232                  case SASL_OK:
 233                         this->user->WriteNumeric(903, "%s :SASL authentication successful", this->user->nick.c_str());
 234                         break;
 235                  case SASL_ABORT:
 236                         this->user->WriteNumeric(906, "%s :SASL authentication aborted", this->user->nick.c_str());
 237                         break;
 238                  case SASL_FAIL:
 239                         this->user->WriteNumeric(904, "%s :SASL authentication failed", this->user->nick.c_str());
 240                         break;
 241                  default:
 242                         break;
 243                 }
 244
 245                 this->state_announced = true;
 246         }
 247 };
 248
 249 class CommandAuthenticate : public Command
 250 {
 251  public:
 252         SimpleExtItem<SaslAuthenticator>& authExt;
 253         GenericCap& cap;
 254         CommandAuthenticate(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext, GenericCap& Cap)
 255                 : Command(Creator, "AUTHENTICATE", 1), authExt(ext), cap(Cap)
 256         {
 257                 works_before_reg = true;
 258                 allow_empty_last_param = false;
 259         }
 260
 261         CmdResult Handle (const std::vector<std::string>& parameters, User *user)
 262         {
 263                 /* Only allow AUTHENTICATE on unregistered clients */
 264                 if (user->registered != REG_ALL)
 265                 {
 266                         if (!cap.ext.get(user))
 267                                 return CMD_FAILURE;
 268
 269                         if (parameters[0].find(' ') != std::string::npos || parameters[0][0] == ':')
 270                                 return CMD_FAILURE;
 271
 272                         SaslAuthenticator *sasl = authExt.get(user);
 273                         if (!sasl)
 274                                 authExt.set(user, new SaslAuthenticator(user, parameters[0]));
 275                         else if (sasl->SendClientMessage(parameters) == false)  // IAL abort extension --nenolod
 276                         {
 277                                 sasl->AnnounceState();
 278                                 authExt.unset(user);
 279                         }
 280                 }
 281                 return CMD_FAILURE;
 282         }
 283 };
 284
 285 class CommandSASL : public Command
 286 {
 287  public:
 288         SimpleExtItem<SaslAuthenticator>& authExt;
 289         CommandSASL(Module* Creator, SimpleExtItem<SaslAuthenticator>& ext) : Command(Creator, "SASL", 2), authExt(ext)
 290         {
 291                 this->flags_needed = FLAG_SERVERONLY; // should not be called by users
 292         }
 293
 294         CmdResult Handle(const std::vector<std::string>& parameters, User *user)
 295         {
 296                 User* target = ServerInstance->FindNick(parameters[1]);
 297                 if ((!target) || (IS_SERVER(target)))
 298                 {
 299                         ServerInstance->Logs->Log("m_sasl", DEBUG,"User not found in sasl ENCAP event: %s", parameters[1].c_str());
 300                         return CMD_FAILURE;
 301                 }
 302
 303                 SaslAuthenticator *sasl = authExt.get(target);
 304                 if (!sasl)
 305                         return CMD_FAILURE;
 306
 307                 SaslState state = sasl->ProcessInboundMessage(parameters);
 308                 if (state == SASL_DONE)
 309                 {
 310                         sasl->AnnounceState();
 311                         authExt.unset(target);
 312                 }
 313                 return CMD_SUCCESS;
 314         }
 315
 316         RouteDescriptor GetRouting(User* user, const std::vector<std::string>& parameters)
 317         {
 318                 return ROUTE_BROADCAST;
 319         }
 320 };
 321
 322 class ModuleSASL : public Module
 323 {
 324         SimpleExtItem<SaslAuthenticator> authExt;
 325         GenericCap cap;
 326         CommandAuthenticate auth;
 327         CommandSASL sasl;
 328  public:
 329         ModuleSASL()
 330                 : authExt("sasl_auth", this), cap(this, "sasl"), auth(this, authExt, cap), sasl(this, authExt)
 331         {
 332         }
 333
 334         void init()
 335         {
 336                 OnRehash(NULL);
 337                 Implementation eventlist[] = { I_OnEvent, I_OnUserConnect, I_OnRehash };
 338                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 339
 340                 ServiceProvider* providelist[] = { &auth, &sasl, &authExt };
 341                 ServerInstance->Modules->AddServices(providelist, 3);
 342
 343                 if (!ServerInstance->Modules->Find("m_services_account.so") || !ServerInstance->Modules->Find("m_cap.so"))
 344                         ServerInstance->Logs->Log("m_sasl", 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!");
 345         }
 346
 347         void OnRehash(User*)
 348         {
 349                 sasl_target = ServerInstance->Config->ConfValue("sasl")->getString("target", "*");
 350         }
 351
 352         void OnUserConnect(LocalUser *user)
 353         {
 354                 SaslAuthenticator *sasl_ = authExt.get(user);
 355                 if (sasl_)
 356                 {
 357                         sasl_->Abort();
 358                         authExt.unset(user);
 359                 }
 360         }
 361
 362         Version GetVersion()
 363         {
 364                 return Version("Provides support for IRC Authentication Layer (aka: SASL) via AUTHENTICATE.", VF_VENDOR);
 365         }
 366
 367         void OnEvent(Event &ev)
 368         {
 369                 cap.HandleEvent(ev);
 370         }
 371 };
 372
 373 MODULE_INIT(ModuleSASL)