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: pkgconfincludes("gnutls","/gnutls/gnutls.h","") */
  26 /* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") */
  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 /** Represents an SSL user's extra data
  34  */
  35 class issl_session : public classbase
  36 {
  37 public:
  38         issl_session()
  39         {
  40                 sess = NULL;
  41         }
  42
  43         gnutls_session_t sess;
  44         issl_status status;
  45         std::string outbuf;
  46 };
  47
  48 class CommandStartTLS : public Command
  49 {
  50  public:
  51         CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance, mod, "STARTTLS", 0, 0, true)
  52         {
  53         }
  54
  55         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  56         {
  57                 /* changed from == REG_ALL to catch clients sending STARTTLS
  58                  * after NICK and USER but before OnUserConnect completes and
  59                  * give a proper error message (see bug #645) - dz
  60                  */
  61                 if (user->registered != REG_NONE)
  62                 {
  63                         user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration has started", user->nick.c_str());
  64                 }
  65                 else
  66                 {
  67                         if (!user->GetIOHook())
  68                         {
  69                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
  70                                 user->AddIOHook(creator);
  71                                 creator->OnRawSocketAccept(user->GetFd(), NULL, NULL);
  72                         }
  73                         else
  74                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
  75                 }
  76
  77                 return CMD_FAILURE;
  78         }
  79 };
  80
  81 class ModuleSSLGnuTLS : public Module
  82 {
  83         std::set<ListenSocketBase*> listenports;
  84
  85         issl_session* sessions;
  86
  87         gnutls_certificate_credentials x509_cred;
  88         gnutls_dh_params dh_params;
  89
  90         std::string keyfile;
  91         std::string certfile;
  92         std::string cafile;
  93         std::string crlfile;
  94         std::string sslports;
  95         int dh_bits;
  96
  97         bool cred_alloc;
  98
  99         CommandStartTLS starttls;
 100
 101  public:
 102
 103         ModuleSSLGnuTLS(InspIRCd* Me)
 104                 : Module(Me), starttls(Me, this)
 105         {
 106                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 107
 108                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 109
 110                 gnutls_global_init(); // This must be called once in the program
 111
 112                 cred_alloc = false;
 113                 // Needs the flag as it ignores a plain /rehash
 114                 OnModuleRehash(NULL,"ssl");
 115
 116                 // Void return, guess we assume success
 117                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 118                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept,
 119                         I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 120                         I_OnBufferFlushed, I_OnRequest, I_OnRehash, I_OnModuleRehash, I_OnPostConnect,
 121                         I_OnEvent, I_OnHookIO };
 122                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 123
 124                 ServerInstance->AddCommand(&starttls);
 125         }
 126
 127         virtual void OnRehash(User* user)
 128         {
 129                 ConfigReader Conf(ServerInstance);
 130
 131                 listenports.clear();
 132                 sslports.clear();
 133
 134                 for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 135                 {
 136                         ListenSocketBase* port = ServerInstance->ports[i];
 137                         std::string desc = port->GetDescription();
 138                         if (desc != "gnutls")
 139                                 continue;
 140
 141                         listenports.insert(port);
 142                         std::string portid = port->GetBindDesc();
 143
 144                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str());
 145                         if (port->GetIP() != "127.0.0.1")
 146                                 sslports.append(portid).append(";");
 147                 }
 148
 149                 if (!sslports.empty())
 150                         sslports.erase(sslports.end() - 1);
 151         }
 152
 153         virtual void OnModuleRehash(User* user, const std::string &param)
 154         {
 155                 if(param != "ssl")
 156                         return;
 157
 158                 OnRehash(user);
 159
 160                 ConfigReader Conf(ServerInstance);
 161
 162                 std::string confdir(ServerInstance->ConfigFileName);
 163                 // +1 so we the path ends with a /
 164                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 165
 166                 cafile = Conf.ReadValue("gnutls", "cafile", 0);
 167                 crlfile = Conf.ReadValue("gnutls", "crlfile", 0);
 168                 certfile = Conf.ReadValue("gnutls", "certfile", 0);
 169                 keyfile = Conf.ReadValue("gnutls", "keyfile", 0);
 170                 dh_bits = Conf.ReadInteger("gnutls", "dhbits", 0, false);
 171
 172                 // Set all the default values needed.
 173                 if (cafile.empty())
 174                         cafile = "ca.pem";
 175
 176                 if (crlfile.empty())
 177                         crlfile = "crl.pem";
 178
 179                 if (certfile.empty())
 180                         certfile = "cert.pem";
 181
 182                 if (keyfile.empty())
 183                         keyfile = "key.pem";
 184
 185                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 186                         dh_bits = 1024;
 187
 188                 // Prepend relative paths with the path to the config directory.
 189                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 190                         cafile = confdir + cafile;
 191
 192                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 193                         crlfile = confdir + crlfile;
 194
 195                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 196                         certfile = confdir + certfile;
 197
 198                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 199                         keyfile = confdir + keyfile;
 200
 201                 int ret;
 202
 203                 if (cred_alloc)
 204                 {
 205                         // Deallocate the old credentials
 206                         gnutls_dh_params_deinit(dh_params);
 207                         gnutls_certificate_free_credentials(x509_cred);
 208                 }
 209                 else
 210                         cred_alloc = true;
 211
 212                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 213                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 214
 215                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 216                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 217
 218                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 219                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));
 220
 221                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 222                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));
 223
 224                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 225                 {
 226                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 227                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + ", key: " + keyfile + "): " + std::string(gnutls_strerror(ret)));
 228                 }
 229
 230                 // This may be on a large (once a day or week) timer eventually.
 231                 GenerateDHParams();
 232         }
 233
 234         void GenerateDHParams()
 235         {
 236                 // Generate Diffie Hellman parameters - for use with DHE
 237                 // kx algorithms. These should be discarded and regenerated
 238                 // once a day, once a week or once a month. Depending on the
 239                 // security requirements.
 240
 241                 int ret;
 242
 243                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 244                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 245         }
 246
 247         virtual ~ModuleSSLGnuTLS()
 248         {
 249                 gnutls_dh_params_deinit(dh_params);
 250                 gnutls_certificate_free_credentials(x509_cred);
 251                 gnutls_global_deinit();
 252                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 253                 delete[] sessions;
 254         }
 255
 256         virtual void OnCleanup(int target_type, void* item)
 257         {
 258                 if(target_type == TYPE_USER)
 259                 {
 260                         User* user = static_cast<User*>(item);
 261
 262                         if (user->GetIOHook() == this)
 263                         {
 264                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 265                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 266                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 267                                 user->DelIOHook();
 268                         }
 269                         if (user->GetExt("ssl_cert"))
 270                         {
 271                                 ssl_cert* tofree;
 272                                 user->GetExt("ssl_cert", tofree);
 273                                 delete tofree;
 274                                 user->Shrink("ssl_cert");
 275                         }
 276                 }
 277         }
 278
 279         virtual Version GetVersion()
 280         {
 281                 return Version("$Id$", VF_VENDOR, API_VERSION);
 282         }
 283
 284
 285         virtual void On005Numeric(std::string &output)
 286         {
 287                 if (!sslports.empty())
 288                         output.append(" SSL=" + sslports);
 289                 output.append(" STARTTLS");
 290         }
 291
 292         virtual void OnHookIO(EventHandler* user, ListenSocketBase* lsb)
 293         {
 294                 if (!user->GetIOHook() && listenports.find(lsb) != listenports.end())
 295                 {
 296                         /* Hook the user with our module */
 297                         user->AddIOHook(this);
 298                 }
 299         }
 300
 301         virtual const char* OnRequest(Request* request)
 302         {
 303                 ISHRequest* ISR = static_cast<ISHRequest*>(request);
 304                 if (strcmp("IS_NAME", request->GetId()) == 0)
 305                 {
 306                         return "gnutls";
 307                 }
 308                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 309                 {
 310                         const char* ret = "OK";
 311                         try
 312                         {
 313                                 ret = ISR->Sock->AddIOHook(this) ? "OK" : NULL;
 314                         }
 315                         catch (ModuleException &e)
 316                         {
 317                                 return NULL;
 318                         }
 319                         return ret;
 320                 }
 321                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 322                 {
 323                         return ISR->Sock->DelIOHook() ? "OK" : NULL;
 324                 }
 325                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 326                 {
 327                         if (ISR->Sock->GetFd() < 0)
 328                                 return "OK";
 329
 330                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 331                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 332                 }
 333                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 334                 {
 335                         if (ISR->Sock->GetFd() > -1)
 336                         {
 337                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 338                                 if (session->sess)
 339                                 {
 340                                         if (static_cast<Extensible*>(ServerInstance->SE->GetRef(ISR->Sock->GetFd())) == static_cast<Extensible*>(ISR->Sock))
 341                                         {
 342                                                 VerifyCertificate(session, ISR->Sock);
 343                                                 return "OK";
 344                                         }
 345                                 }
 346                         }
 347                 }
 348                 else if (strcmp("GET_FP", request->GetId()) == 0)
 349                 {
 350                         if (ISR->Sock->GetFd() > -1)
 351                         {
 352                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 353                                 if (session->sess)
 354                                 {
 355                                         Extensible* ext = ISR->Sock;
 356                                         ssl_cert* certinfo;
 357                                         if (ext->GetExt("ssl_cert",certinfo))
 358                                                 return certinfo->GetFingerprint().c_str();
 359                                 }
 360                         }
 361                 }
 362                 return NULL;
 363         }
 364
 365
 366         virtual void OnRawSocketAccept(int fd, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 367         {
 368                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 369                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 370                         return;
 371
 372                 issl_session* session = &sessions[fd];
 373
 374                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 375                 if (session->sess)
 376                         return;
 377
 378                 gnutls_init(&session->sess, GNUTLS_SERVER);
 379
 380                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 381                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 382                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 383
 384                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(fd)); // Give gnutls the fd for the socket.
 385
 386                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 387
 388                 Handshake(session, fd);
 389         }
 390
 391         virtual void OnRawSocketConnect(int fd)
 392         {
 393                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 394                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 395                         return;
 396
 397                 issl_session* session = &sessions[fd];
 398
 399                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 400
 401                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 402                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 403                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 404                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(fd)); // Give gnutls the fd for the socket.
 405
 406                 Handshake(session, fd);
 407         }
 408
 409         virtual void OnRawSocketClose(int fd)
 410         {
 411                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 412                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 413                         return;
 414
 415                 CloseSession(&sessions[fd]);
 416
 417                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 418
 419                 if ((user) && (user->GetExt("ssl_cert")))
 420                 {
 421                         ssl_cert* tofree;
 422                         user->GetExt("ssl_cert", tofree);
 423                         delete tofree;
 424                         user->Shrink("ssl_cert");
 425                 }
 426         }
 427
 428         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 429         {
 430                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 431                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 432                         return 0;
 433
 434                 issl_session* session = &sessions[fd];
 435
 436                 if (!session->sess)
 437                 {
 438                         readresult = 0;
 439                         CloseSession(session);
 440                         return 1;
 441                 }
 442
 443                 if (session->status == ISSL_HANDSHAKING_READ)
 444                 {
 445                         // The handshake isn't finished, try to finish it.
 446
 447                         if(!Handshake(session, fd))
 448                         {
 449                                 errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 450                                 // Couldn't resume handshake.
 451                                 return -1;
 452                         }
 453                 }
 454                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 455                 {
 456                         errno = EAGAIN;
 457                         MakePollWrite(fd);
 458                         return -1;
 459                 }
 460
 461                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 462
 463                 if (session->status == ISSL_HANDSHAKEN)
 464                 {
 465                         unsigned int len = 0;
 466                         while (len < count)
 467                         {
 468                                 int ret = gnutls_record_recv(session->sess, buffer + len, count - len);
 469                                 if (ret > 0)
 470                                 {
 471                                         len += ret;
 472                                 }
 473                                 else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 474                                 {
 475                                         break;
 476                                 }
 477                                 else
 478                                 {
 479                                         if (ret != 0)
 480                                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 481                                                         "m_ssl_gnutls.so: Error while reading on fd %d: %s",
 482                                                         fd, gnutls_strerror(ret));
 483
 484                                         // if ret == 0, client closed connection.
 485                                         readresult = 0;
 486                                         CloseSession(session);
 487                                         return 1;
 488                                 }
 489                         }
 490                         readresult = len;
 491                         if (len)
 492                         {
 493                                 return 1;
 494                         }
 495                         else
 496                         {
 497                                 errno = EAGAIN;
 498                                 return -1;
 499                         }
 500                 }
 501                 else if (session->status == ISSL_CLOSING)
 502                         readresult = 0;
 503
 504                 return 1;
 505         }
 506
 507         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 508         {
 509                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 510                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 511                         return 0;
 512
 513                 issl_session* session = &sessions[fd];
 514                 const char* sendbuffer = buffer;
 515
 516                 if (!session->sess)
 517                 {
 518                         CloseSession(session);
 519                         return 1;
 520                 }
 521
 522                 session->outbuf.append(sendbuffer, count);
 523                 sendbuffer = session->outbuf.c_str();
 524                 count = session->outbuf.size();
 525
 526                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 527                 {
 528                         // The handshake isn't finished, try to finish it.
 529                         Handshake(session, fd);
 530                         errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 531                         return -1;
 532                 }
 533
 534                 int ret = 0;
 535
 536                 if (session->status == ISSL_HANDSHAKEN)
 537                 {
 538                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 539
 540                         if (ret == 0)
 541                         {
 542                                 CloseSession(session);
 543                         }
 544                         else if (ret < 0)
 545                         {
 546                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 547                                 {
 548                                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 549                                                         "m_ssl_gnutls.so: Error while writing to fd %d: %s",
 550                                                         fd, gnutls_strerror(ret));
 551                                         CloseSession(session);
 552                                 }
 553                                 else
 554                                 {
 555                                         errno = EAGAIN;
 556                                 }
 557                         }
 558                         else
 559                         {
 560                                 session->outbuf = session->outbuf.substr(ret);
 561                         }
 562                 }
 563
 564                 if (!session->outbuf.empty())
 565                         MakePollWrite(fd);
 566
 567                 /* Who's smart idea was it to return 1 when we havent written anything?
 568                  * This fucks the buffer up in BufferedSocket :p
 569                  */
 570                 return ret < 1 ? 0 : ret;
 571         }
 572
 573         bool Handshake(issl_session* session, int fd)
 574         {
 575                 int ret = gnutls_handshake(session->sess);
 576
 577                 if (ret < 0)
 578                 {
 579                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 580                         {
 581                                 // Handshake needs resuming later, read() or write() would have blocked.
 582
 583                                 if(gnutls_record_get_direction(session->sess) == 0)
 584                                 {
 585                                         // gnutls_handshake() wants to read() again.
 586                                         session->status = ISSL_HANDSHAKING_READ;
 587                                 }
 588                                 else
 589                                 {
 590                                         // gnutls_handshake() wants to write() again.
 591                                         session->status = ISSL_HANDSHAKING_WRITE;
 592                                         MakePollWrite(fd);
 593                                 }
 594                         }
 595                         else
 596                         {
 597                                 // Handshake failed.
 598                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 599                                                 "m_ssl_gnutls.so: Handshake failed on fd %d: %s",
 600                                                 fd, gnutls_strerror(ret));
 601                                 CloseSession(session);
 602                                 session->status = ISSL_CLOSING;
 603                         }
 604
 605                         return false;
 606                 }
 607                 else
 608                 {
 609                         // Handshake complete.
 610                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 611                         EventHandler *extendme = ServerInstance->SE->GetRef(fd);
 612                         if (extendme)
 613                         {
 614                                 extendme->Extend("ssl");
 615                         }
 616
 617                         // Change the seesion state
 618                         session->status = ISSL_HANDSHAKEN;
 619
 620                         // Finish writing, if any left
 621                         MakePollWrite(fd);
 622
 623                         return true;
 624                 }
 625         }
 626
 627         virtual void OnPostConnect(User* user)
 628         {
 629                 // This occurs AFTER OnUserConnect so we can be sure the
 630                 // protocol module has propagated the NICK message.
 631                 if (user->GetIOHook() == this && (IS_LOCAL(user)))
 632                 {
 633                         ssl_cert* certdata = VerifyCertificate(&sessions[user->GetFd()],user);
 634                         if (sessions[user->GetFd()].sess)
 635                         {
 636                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 637                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 638                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 639                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 640                         }
 641
 642                         ServerInstance->PI->SendMetaData(user, "ssl", "ON");
 643                         if (certdata)
 644                                 ServerInstance->PI->SendMetaData(user, "ssl_cert", certdata->GetMetaLine().c_str());
 645                 }
 646         }
 647
 648         void MakePollWrite(int fd)
 649         {
 650                 //OnRawSocketWrite(fd, NULL, 0);
 651                 EventHandler* eh = ServerInstance->SE->GetRef(fd);
 652                 if (eh)
 653                         ServerInstance->SE->WantWrite(eh);
 654         }
 655
 656         virtual void OnBufferFlushed(User* user)
 657         {
 658                 if (user->GetIOHook() == this)
 659                 {
 660                         issl_session* session = &sessions[user->GetFd()];
 661                         if (session && session->outbuf.size())
 662                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 663                 }
 664         }
 665
 666         void CloseSession(issl_session* session)
 667         {
 668                 if(session->sess)
 669                 {
 670                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 671                         gnutls_deinit(session->sess);
 672                 }
 673
 674                 session->outbuf.clear();
 675                 session->sess = NULL;
 676                 session->status = ISSL_NONE;
 677         }
 678
 679         ssl_cert* VerifyCertificate(issl_session* session, Extensible* user)
 680         {
 681                 if (!session->sess || !user)
 682                         return NULL;
 683
 684                 unsigned int status;
 685                 const gnutls_datum_t* cert_list;
 686                 int ret;
 687                 unsigned int cert_list_size;
 688                 gnutls_x509_crt_t cert;
 689                 char name[MAXBUF];
 690                 unsigned char digest[MAXBUF];
 691                 size_t digest_size = sizeof(digest);
 692                 size_t name_size = sizeof(name);
 693                 ssl_cert* certinfo = new ssl_cert;
 694
 695                 user->Extend("ssl_cert",certinfo);
 696
 697                 /* This verification function uses the trusted CAs in the credentials
 698                  * structure. So you must have installed one or more CA certificates.
 699                  */
 700                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 701
 702                 if (ret < 0)
 703                 {
 704                         certinfo->error = std::string(gnutls_strerror(ret));
 705                         return certinfo;
 706                 }
 707
 708                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 709                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 710                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 711                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 712
 713                 /* Up to here the process is the same for X.509 certificates and
 714                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 715                  * be easily extended to work with openpgp keys as well.
 716                  */
 717                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 718                 {
 719                         certinfo->error = "No X509 keys sent";
 720                         return certinfo;
 721                 }
 722
 723                 ret = gnutls_x509_crt_init(&cert);
 724                 if (ret < 0)
 725                 {
 726                         certinfo->error = gnutls_strerror(ret);
 727                         return certinfo;
 728                 }
 729
 730                 cert_list_size = 0;
 731                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 732                 if (cert_list == NULL)
 733                 {
 734                         certinfo->error = "No certificate was found";
 735                         return certinfo;
 736                 }
 737
 738                 /* This is not a real world example, since we only check the first
 739                  * certificate in the given chain.
 740                  */
 741
 742                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 743                 if (ret < 0)
 744                 {
 745                         certinfo->error = gnutls_strerror(ret);
 746                         return certinfo;
 747                 }
 748
 749                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 750                 certinfo->dn = name;
 751
 752                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 753                 certinfo->issuer = name;
 754
 755                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 756                 {
 757                         certinfo->error = gnutls_strerror(ret);
 758                 }
 759                 else
 760                 {
 761                         certinfo->fingerprint = irc::hex(digest, digest_size);
 762                 }
 763
 764                 /* Beware here we do not check for errors.
 765                  */
 766                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 767                 {
 768                         certinfo->error = "Not activated, or expired certificate";
 769                 }
 770
 771                 gnutls_x509_crt_deinit(cert);
 772
 773                 return certinfo;
 774         }
 775
 776         void OnEvent(Event* ev)
 777         {
 778                 GenericCapHandler(ev, "tls", "tls");
 779         }
 780
 781         void Prioritize()
 782         {
 783                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 784                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIORITY_AFTER, &server);
 785         }
 786 };
 787
 788 MODULE_INIT(ModuleSSLGnuTLS)