src/modules/extra/m_ssl_gnutls.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *          the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include <gnutls/gnutls.h>
  16 #include <gnutls/x509.h>
  17 #include "transport.h"
  18 #include "m_cap.h"
  19
  20 #ifdef WINDOWS
  21 #pragma comment(lib, "libgnutls-13.lib")
  22 #endif
  23
  24 /* $ModDesc: Provides SSL support for clients */
  25 /* $CompileFlags: exec("libgnutls-config --cflags") */
  26 /* $LinkerFlags: rpath("libgnutls-config --libs") exec("libgnutls-config --libs") */
  27 /* $ModDep: transport.h */
  28 /* $CopyInstall: conf/key.pem $(CONPATH) */
  29 /* $CopyInstall: conf/cert.pem $(CONPATH) */
  30
  31 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  32
  33 bool isin(const std::string &host, int port, const std::vector<std::string> &portlist)
  34 {
  35         if (std::find(portlist.begin(), portlist.end(), "*:" + ConvToStr(port)) != portlist.end())
  36                 return true;
  37
  38         if (std::find(portlist.begin(), portlist.end(), ":" + ConvToStr(port)) != portlist.end())
  39                 return true;
  40
  41         return std::find(portlist.begin(), portlist.end(), host + ":" + ConvToStr(port)) != portlist.end();
  42 }
  43
  44 /** Represents an SSL user's extra data
  45  */
  46 class issl_session : public classbase
  47 {
  48 public:
  49         issl_session()
  50         {
  51                 sess = NULL;
  52         }
  53
  54         gnutls_session_t sess;
  55         issl_status status;
  56         std::string outbuf;
  57 };
  58
  59 class CommandStartTLS : public Command
  60 {
  61         Module* Caller;
  62  public:
  63         CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance,"STARTTLS", 0, 0, true), Caller(mod)
  64         {
  65                 this->source = "m_ssl_gnutls.so";
  66         }
  67
  68         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  69         {
  70                 /* changed from == REG_ALL to catch clients sending STARTTLS
  71                  * after NICK and USER but before OnUserConnect completes and
  72                  * give a proper error message (see bug #645) - dz
  73                  */
  74                 if (user->registered != REG_NONE)
  75                 {
  76                         ServerInstance->Users->QuitUser(user, "STARTTLS is not permitted after client registration has started");
  77                 }
  78                 else
  79                 {
  80                         if (!user->GetIOHook())
  81                         {
  82                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
  83                                 user->AddIOHook(Caller);
  84                                 Caller->OnRawSocketAccept(user->GetFd(), user->GetIPString(), user->GetPort());
  85                         }
  86                         else
  87                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
  88                 }
  89
  90                 return CMD_FAILURE;
  91         }
  92 };
  93
  94 class ModuleSSLGnuTLS : public Module
  95 {
  96
  97         ConfigReader* Conf;
  98
  99         char* dummy;
 100
 101         std::vector<std::string> listenports;
 102
 103         issl_session* sessions;
 104
 105         gnutls_certificate_credentials x509_cred;
 106         gnutls_dh_params dh_params;
 107
 108         std::string keyfile;
 109         std::string certfile;
 110         std::string cafile;
 111         std::string crlfile;
 112         std::string sslports;
 113         int dh_bits;
 114
 115         int clientactive;
 116         bool cred_alloc;
 117
 118         CommandStartTLS* starttls;
 119
 120  public:
 121
 122         ModuleSSLGnuTLS(InspIRCd* Me)
 123                 : Module(Me)
 124         {
 125                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 126
 127                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 128
 129                 gnutls_global_init(); // This must be called once in the program
 130
 131                 cred_alloc = false;
 132                 // Needs the flag as it ignores a plain /rehash
 133                 OnRehash(NULL,"ssl");
 134
 135                 // Void return, guess we assume success
 136                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 137                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 138                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData, I_OnUnloadModule, I_OnRehash, I_OnWhois, I_OnPostConnect, I_OnEvent, I_OnHookUserIO };
 139                 ServerInstance->Modules->Attach(eventlist, this, 17);
 140
 141                 starttls = new CommandStartTLS(ServerInstance, this);
 142                 ServerInstance->AddCommand(starttls);
 143         }
 144
 145         virtual void OnRehash(User* user, const std::string &param)
 146         {
 147                 Conf = new ConfigReader(ServerInstance);
 148
 149                 listenports.clear();
 150                 clientactive = 0;
 151                 sslports.clear();
 152
 153                 for(int index = 0; index < Conf->Enumerate("bind"); index++)
 154                 {
 155                         // For each <bind> tag
 156                         std::string x = Conf->ReadValue("bind", "type", index);
 157                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", index) == "gnutls"))
 158                         {
 159                                 // Get the port we're meant to be listening on with SSL
 160                                 std::string port = Conf->ReadValue("bind", "port", index);
 161                                 std::string addr = Conf->ReadValue("bind", "address", index);
 162
 163                                 if (!addr.empty())
 164                                 {
 165                                         // normalize address, important for IPv6
 166                                         int portint = 0;
 167                                         irc::sockets::sockaddrs bin;
 168                                         if (irc::sockets::aptosa(addr.c_str(), portint, &bin))
 169                                                 irc::sockets::satoap(&bin, addr, portint);
 170                                 }
 171
 172                                 irc::portparser portrange(port, false);
 173                                 long portno = -1;
 174                                 while ((portno = portrange.GetToken()))
 175                                 {
 176                                         clientactive++;
 177                                         try
 178                                         {
 179                                                 listenports.push_back(addr + ":" + ConvToStr(portno));
 180
 181                                                 for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
 182                                                         if ((ServerInstance->Config->ports[i]->GetPort() == portno) && (ServerInstance->Config->ports[i]->GetIP() == addr))
 183                                                                 ServerInstance->Config->ports[i]->SetDescription("ssl");
 184                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %ld", portno);
 185
 186                                                 sslports.append((addr.empty() ? "*" : addr)).append(":").append(ConvToStr(portno)).append(";");
 187                                         }
 188                                         catch (ModuleException &e)
 189                                         {
 190                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: FAILED to enable SSL on port %ld: %s. Maybe it's already hooked by the same port on a different IP, or you have an other SSL or similar module loaded?", portno, e.GetReason());
 191                                         }
 192                                 }
 193                         }
 194                 }
 195
 196                 if (!sslports.empty())
 197                         sslports.erase(sslports.end() - 1);
 198
 199                 if(param != "ssl")
 200                 {
 201                         delete Conf;
 202                         return;
 203                 }
 204
 205                 std::string confdir(ServerInstance->ConfigFileName);
 206                 // +1 so we the path ends with a /
 207                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 208
 209                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 210                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 211                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 212                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 213                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 214
 215                 // Set all the default values needed.
 216                 if (cafile.empty())
 217                         cafile = "ca.pem";
 218
 219                 if (crlfile.empty())
 220                         crlfile = "crl.pem";
 221
 222                 if (certfile.empty())
 223                         certfile = "cert.pem";
 224
 225                 if (keyfile.empty())
 226                         keyfile = "key.pem";
 227
 228                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 229                         dh_bits = 1024;
 230
 231                 // Prepend relative paths with the path to the config directory.
 232                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 233                         cafile = confdir + cafile;
 234
 235                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 236                         crlfile = confdir + crlfile;
 237
 238                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 239                         certfile = confdir + certfile;
 240
 241                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 242                         keyfile = confdir + keyfile;
 243
 244                 int ret;
 245
 246                 if (cred_alloc)
 247                 {
 248                         // Deallocate the old credentials
 249                         gnutls_dh_params_deinit(dh_params);
 250                         gnutls_certificate_free_credentials(x509_cred);
 251                 }
 252                 else
 253                         cred_alloc = true;
 254
 255                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 256                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 257
 258                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 259                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 260
 261                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 262                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));
 263
 264                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 265                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));
 266
 267                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 268                 {
 269                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 270                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + ", key: " + keyfile + "): " + std::string(gnutls_strerror(ret)));
 271                 }
 272
 273                 // This may be on a large (once a day or week) timer eventually.
 274                 GenerateDHParams();
 275
 276                 delete Conf;
 277         }
 278
 279         void GenerateDHParams()
 280         {
 281                 // Generate Diffie Hellman parameters - for use with DHE
 282                 // kx algorithms. These should be discarded and regenerated
 283                 // once a day, once a week or once a month. Depending on the
 284                 // security requirements.
 285
 286                 int ret;
 287
 288                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 289                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 290         }
 291
 292         virtual ~ModuleSSLGnuTLS()
 293         {
 294                 gnutls_dh_params_deinit(dh_params);
 295                 gnutls_certificate_free_credentials(x509_cred);
 296                 gnutls_global_deinit();
 297                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 298                 delete[] sessions;
 299         }
 300
 301         virtual void OnCleanup(int target_type, void* item)
 302         {
 303                 if(target_type == TYPE_USER)
 304                 {
 305                         User* user = (User*)item;
 306
 307                         if (user->GetIOHook() == this)
 308                         {
 309                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 310                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 311                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 312                                 user->DelIOHook();
 313                         }
 314                         if (user->GetExt("ssl_cert", dummy))
 315                         {
 316                                 ssl_cert* tofree;
 317                                 user->GetExt("ssl_cert", tofree);
 318                                 delete tofree;
 319                                 user->Shrink("ssl_cert");
 320                         }
 321                 }
 322         }
 323
 324         virtual void OnUnloadModule(Module* mod, const std::string &name)
 325         {
 326                 if(mod == this)
 327                 {
 328                         for(unsigned int i = 0; i < listenports.size(); i++)
 329                         {
 330                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 331                                         if (listenports[i] == (ServerInstance->Config->ports[j]->GetIP()+":"+ConvToStr(ServerInstance->Config->ports[j]->GetPort())))
 332                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 333                         }
 334                 }
 335         }
 336
 337         virtual Version GetVersion()
 338         {
 339                 return Version("$Id$", VF_VENDOR, API_VERSION);
 340         }
 341
 342
 343         virtual void On005Numeric(std::string &output)
 344         {
 345                 if (!sslports.empty())
 346                         output.append(" SSL=" + sslports);
 347                 output.append(" STARTTLS");
 348         }
 349
 350         virtual void OnHookUserIO(User* user, const std::string &targetip)
 351         {
 352                 if (!user->GetIOHook() && isin(targetip,user->GetPort(),listenports))
 353                 {
 354                         /* Hook the user with our module */
 355                         user->AddIOHook(this);
 356                 }
 357         }
 358
 359         virtual const char* OnRequest(Request* request)
 360         {
 361                 ISHRequest* ISR = (ISHRequest*)request;
 362                 if (strcmp("IS_NAME", request->GetId()) == 0)
 363                 {
 364                         return "gnutls";
 365                 }
 366                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 367                 {
 368                         const char* ret = "OK";
 369                         try
 370                         {
 371                                 ret = ISR->Sock->AddIOHook((Module*)this) ? "OK" : NULL;
 372                         }
 373                         catch (ModuleException &e)
 374                         {
 375                                 return NULL;
 376                         }
 377                         return ret;
 378                 }
 379                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 380                 {
 381                         return ISR->Sock->DelIOHook() ? "OK" : NULL;
 382                 }
 383                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 384                 {
 385                         if (ISR->Sock->GetFd() < 0)
 386                                 return "OK";
 387
 388                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 389                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 390                 }
 391                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 392                 {
 393                         if (ISR->Sock->GetFd() > -1)
 394                         {
 395                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 396                                 if (session->sess)
 397                                 {
 398                                         if ((Extensible*)ServerInstance->SE->GetRef(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 399                                         {
 400                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 401                                                 return "OK";
 402                                         }
 403                                 }
 404                         }
 405                 }
 406                 return NULL;
 407         }
 408
 409
 410         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 411         {
 412                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 413                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 414                         return;
 415
 416                 issl_session* session = &sessions[fd];
 417
 418                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 419                 if (session->sess)
 420                         return;
 421
 422                 gnutls_init(&session->sess, GNUTLS_SERVER);
 423
 424                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 425                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 426                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 427
 428                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 429
 430                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 431
 432                 Handshake(session, fd);
 433         }
 434
 435         virtual void OnRawSocketConnect(int fd)
 436         {
 437                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 438                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 439                         return;
 440
 441                 issl_session* session = &sessions[fd];
 442
 443                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 444
 445                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 446                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 447                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 448                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 449
 450                 Handshake(session, fd);
 451         }
 452
 453         virtual void OnRawSocketClose(int fd)
 454         {
 455                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 456                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 457                         return;
 458
 459                 CloseSession(&sessions[fd]);
 460
 461                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 462
 463                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 464                 {
 465                         ssl_cert* tofree;
 466                         user->GetExt("ssl_cert", tofree);
 467                         delete tofree;
 468                         user->Shrink("ssl_cert");
 469                 }
 470         }
 471
 472         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 473         {
 474                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 475                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 476                         return 0;
 477
 478                 issl_session* session = &sessions[fd];
 479
 480                 if (!session->sess)
 481                 {
 482                         readresult = 0;
 483                         CloseSession(session);
 484                         return 1;
 485                 }
 486
 487                 if (session->status == ISSL_HANDSHAKING_READ)
 488                 {
 489                         // The handshake isn't finished, try to finish it.
 490
 491                         if(!Handshake(session, fd))
 492                         {
 493                                 errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 494                                 // Couldn't resume handshake.
 495                                 return -1;
 496                         }
 497                 }
 498                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 499                 {
 500                         errno = EAGAIN;
 501                         MakePollWrite(fd);
 502                         return -1;
 503                 }
 504
 505                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 506
 507                 if (session->status == ISSL_HANDSHAKEN)
 508                 {
 509                         int ret = gnutls_record_recv(session->sess, buffer, count);
 510
 511                         if (ret > 0)
 512                         {
 513                                 readresult = ret;
 514                         }
 515                         else if (ret == 0)
 516                         {
 517                                 // Client closed connection.
 518                                 readresult = 0;
 519                                 CloseSession(session);
 520                                 return 1;
 521                         }
 522                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 523                         {
 524                                 errno = EAGAIN;
 525                                 return -1;
 526                         }
 527                         else
 528                         {
 529                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 530                                                 "m_ssl_gnutls.so: Error while reading on fd %d: %s",
 531                                                 fd, gnutls_strerror(ret));
 532                                 readresult = 0;
 533                                 CloseSession(session);
 534                         }
 535                 }
 536                 else if(session->status == ISSL_CLOSING)
 537                         readresult = 0;
 538
 539                 return 1;
 540         }
 541
 542         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 543         {
 544                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 545                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 546                         return 0;
 547
 548                 issl_session* session = &sessions[fd];
 549                 const char* sendbuffer = buffer;
 550
 551                 if (!session->sess)
 552                 {
 553                         CloseSession(session);
 554                         return 1;
 555                 }
 556
 557                 session->outbuf.append(sendbuffer, count);
 558                 sendbuffer = session->outbuf.c_str();
 559                 count = session->outbuf.size();
 560
 561                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 562                 {
 563                         // The handshake isn't finished, try to finish it.
 564                         Handshake(session, fd);
 565                         errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 566                         return -1;
 567                 }
 568
 569                 int ret = 0;
 570
 571                 if (session->status == ISSL_HANDSHAKEN)
 572                 {
 573                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 574
 575                         if (ret == 0)
 576                         {
 577                                 CloseSession(session);
 578                         }
 579                         else if (ret < 0)
 580                         {
 581                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 582                                 {
 583                                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 584                                                         "m_ssl_gnutls.so: Error while writing to fd %d: %s",
 585                                                         fd, gnutls_strerror(ret));
 586                                         CloseSession(session);
 587                                 }
 588                                 else
 589                                 {
 590                                         errno = EAGAIN;
 591                                 }
 592                         }
 593                         else
 594                         {
 595                                 session->outbuf = session->outbuf.substr(ret);
 596                         }
 597                 }
 598
 599                 MakePollWrite(fd);
 600
 601                 /* Who's smart idea was it to return 1 when we havent written anything?
 602                  * This fucks the buffer up in BufferedSocket :p
 603                  */
 604                 return ret < 1 ? 0 : ret;
 605         }
 606
 607         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 608         virtual void OnWhois(User* source, User* dest)
 609         {
 610                 if (!clientactive)
 611                         return;
 612
 613                 // Bugfix, only send this numeric for *our* SSL users
 614                 if (dest->GetExt("ssl", dummy))
 615                 {
 616                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick.c_str(), dest->nick.c_str());
 617                 }
 618         }
 619
 620         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 621         {
 622                 // check if the linking module wants to know about OUR metadata
 623                 if(extname == "ssl")
 624                 {
 625                         // check if this user has an swhois field to send
 626                         if(user->GetExt(extname, dummy))
 627                         {
 628                                 // call this function in the linking module, let it format the data how it
 629                                 // sees fit, and send it on its way. We dont need or want to know how.
 630                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 631                         }
 632                 }
 633         }
 634
 635         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 636         {
 637                 // check if its our metadata key, and its associated with a user
 638                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 639                 {
 640                         User* dest = (User*)target;
 641                         // if they dont already have an ssl flag, accept the remote server's
 642                         if (!dest->GetExt(extname, dummy))
 643                         {
 644                                 dest->Extend(extname, "ON");
 645                         }
 646                 }
 647         }
 648
 649         bool Handshake(issl_session* session, int fd)
 650         {
 651                 int ret = gnutls_handshake(session->sess);
 652
 653                 if (ret < 0)
 654                 {
 655                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 656                         {
 657                                 // Handshake needs resuming later, read() or write() would have blocked.
 658
 659                                 if(gnutls_record_get_direction(session->sess) == 0)
 660                                 {
 661                                         // gnutls_handshake() wants to read() again.
 662                                         session->status = ISSL_HANDSHAKING_READ;
 663                                 }
 664                                 else
 665                                 {
 666                                         // gnutls_handshake() wants to write() again.
 667                                         session->status = ISSL_HANDSHAKING_WRITE;
 668                                         MakePollWrite(fd);
 669                                 }
 670                         }
 671                         else
 672                         {
 673                                 // Handshake failed.
 674                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 675                                                 "m_ssl_gnutls.so: Handshake failed on fd %d: %s",
 676                                                 fd, gnutls_strerror(ret));
 677                                 CloseSession(session);
 678                                 session->status = ISSL_CLOSING;
 679                         }
 680
 681                         return false;
 682                 }
 683                 else
 684                 {
 685                         // Handshake complete.
 686                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 687                         EventHandler *extendme = ServerInstance->SE->GetRef(fd);
 688                         if (extendme)
 689                         {
 690                                 if (!extendme->GetExt("ssl", dummy))
 691                                         extendme->Extend("ssl", "ON");
 692                         }
 693
 694                         // Change the seesion state
 695                         session->status = ISSL_HANDSHAKEN;
 696
 697                         // Finish writing, if any left
 698                         MakePollWrite(fd);
 699
 700                         return true;
 701                 }
 702         }
 703
 704         virtual void OnPostConnect(User* user)
 705         {
 706                 // This occurs AFTER OnUserConnect so we can be sure the
 707                 // protocol module has propagated the NICK message.
 708                 if (user->GetIOHook() == this && (IS_LOCAL(user)))
 709                 {
 710                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 711                         ServerInstance->PI->SendMetaData(user, TYPE_USER, "ssl", "on");
 712
 713                         VerifyCertificate(&sessions[user->GetFd()],user);
 714                         if (sessions[user->GetFd()].sess)
 715                         {
 716                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 717                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 718                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 719                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 720                         }
 721                 }
 722         }
 723
 724         void MakePollWrite(int fd)
 725         {
 726                 //OnRawSocketWrite(fd, NULL, 0);
 727                 EventHandler* eh = ServerInstance->SE->GetRef(fd);
 728                 if (eh)
 729                         ServerInstance->SE->WantWrite(eh);
 730         }
 731
 732         virtual void OnBufferFlushed(User* user)
 733         {
 734                 if (user->GetIOHook() == this)
 735                 {
 736                         issl_session* session = &sessions[user->GetFd()];
 737                         if (session && session->outbuf.size())
 738                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 739                 }
 740         }
 741
 742         void CloseSession(issl_session* session)
 743         {
 744                 if(session->sess)
 745                 {
 746                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 747                         gnutls_deinit(session->sess);
 748                 }
 749
 750                 session->outbuf.clear();
 751                 session->sess = NULL;
 752                 session->status = ISSL_NONE;
 753         }
 754
 755         void VerifyCertificate(issl_session* session, Extensible* user)
 756         {
 757                 if (!session->sess || !user)
 758                         return;
 759
 760                 unsigned int status;
 761                 const gnutls_datum_t* cert_list;
 762                 int ret;
 763                 unsigned int cert_list_size;
 764                 gnutls_x509_crt_t cert;
 765                 char name[MAXBUF];
 766                 unsigned char digest[MAXBUF];
 767                 size_t digest_size = sizeof(digest);
 768                 size_t name_size = sizeof(name);
 769                 ssl_cert* certinfo = new ssl_cert;
 770
 771                 user->Extend("ssl_cert",certinfo);
 772
 773                 /* This verification function uses the trusted CAs in the credentials
 774                  * structure. So you must have installed one or more CA certificates.
 775                  */
 776                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 777
 778                 if (ret < 0)
 779                 {
 780                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 781                         return;
 782                 }
 783
 784                 if (status & GNUTLS_CERT_INVALID)
 785                 {
 786                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 787                 }
 788                 else
 789                 {
 790                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 791                 }
 792                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 793                 {
 794                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 795                 }
 796                 else
 797                 {
 798                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 799                 }
 800                 if (status & GNUTLS_CERT_REVOKED)
 801                 {
 802                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 803                 }
 804                 else
 805                 {
 806                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 807                 }
 808                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 809                 {
 810                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 811                 }
 812                 else
 813                 {
 814                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 815                 }
 816
 817                 /* Up to here the process is the same for X.509 certificates and
 818                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 819                  * be easily extended to work with openpgp keys as well.
 820                  */
 821                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 822                 {
 823                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 824                         return;
 825                 }
 826
 827                 ret = gnutls_x509_crt_init(&cert);
 828                 if (ret < 0)
 829                 {
 830                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 831                         return;
 832                 }
 833
 834                 cert_list_size = 0;
 835                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 836                 if (cert_list == NULL)
 837                 {
 838                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 839                         return;
 840                 }
 841
 842                 /* This is not a real world example, since we only check the first
 843                  * certificate in the given chain.
 844                  */
 845
 846                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 847                 if (ret < 0)
 848                 {
 849                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 850                         return;
 851                 }
 852
 853                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 854
 855                 certinfo->data.insert(std::make_pair("dn",name));
 856
 857                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 858
 859                 certinfo->data.insert(std::make_pair("issuer",name));
 860
 861                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 862                 {
 863                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 864                 }
 865                 else
 866                 {
 867                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 868                 }
 869
 870                 /* Beware here we do not check for errors.
 871                  */
 872                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 873                 {
 874                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 875                 }
 876
 877                 gnutls_x509_crt_deinit(cert);
 878
 879                 return;
 880         }
 881
 882         void OnEvent(Event* ev)
 883         {
 884                 GenericCapHandler(ev, "tls", "tls");
 885         }
 886
 887         void Prioritize()
 888         {
 889                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 890                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIORITY_AFTER, &server);
 891         }
 892 };
 893
 894 MODULE_INIT(ModuleSSLGnuTLS)