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