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 static gnutls_x509_crt_t x509_cert;
  34 static gnutls_x509_privkey_t x509_key;
  35 static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs,
  36         const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr_st * st) {
  37
  38         st->type = GNUTLS_CRT_X509;
  39         st->ncerts = 1;
  40         st->cert.x509 = &x509_cert;
  41         st->key.x509 = x509_key;
  42         st->deinit_all = 0;
  43
  44         return 0;
  45 }
  46
  47 /** Represents an SSL user's extra data
  48  */
  49 class issl_session : public classbase
  50 {
  51 public:
  52         issl_session()
  53         {
  54                 sess = NULL;
  55         }
  56
  57         gnutls_session_t sess;
  58         issl_status status;
  59         std::string outbuf;
  60 };
  61
  62 class CommandStartTLS : public Command
  63 {
  64  public:
  65         CommandStartTLS (Module* mod) : Command(mod, "STARTTLS")
  66         {
  67                 works_before_reg = true;
  68         }
  69
  70         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  71         {
  72                 /* changed from == REG_ALL to catch clients sending STARTTLS
  73                  * after NICK and USER but before OnUserConnect completes and
  74                  * give a proper error message (see bug #645) - dz
  75                  */
  76                 if (user->registered != REG_NONE)
  77                 {
  78                         user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration has started", user->nick.c_str());
  79                 }
  80                 else
  81                 {
  82                         if (!user->GetIOHook())
  83                         {
  84                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
  85                                 user->AddIOHook(creator);
  86                                 creator->OnRawSocketAccept(user->GetFd(), NULL, NULL);
  87                         }
  88                         else
  89                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
  90                 }
  91
  92                 return CMD_FAILURE;
  93         }
  94 };
  95
  96 class ModuleSSLGnuTLS : public Module
  97 {
  98         std::set<ListenSocketBase*> listenports;
  99
 100         issl_session* sessions;
 101
 102         gnutls_certificate_credentials x509_cred;
 103         gnutls_dh_params dh_params;
 104
 105         std::string keyfile;
 106         std::string certfile;
 107         std::string cafile;
 108         std::string crlfile;
 109         std::string sslports;
 110         int dh_bits;
 111
 112         bool cred_alloc;
 113
 114         CommandStartTLS starttls;
 115
 116         GenericCap capHandler;
 117  public:
 118
 119         ModuleSSLGnuTLS(InspIRCd* Me)
 120                 : Module(Me), starttls(this), capHandler(this, "tls")
 121         {
 122                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 123
 124                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 125
 126                 gnutls_global_init(); // This must be called once in the program
 127                 gnutls_x509_crt_init(&x509_cert);
 128                 gnutls_x509_privkey_init(&x509_key);
 129
 130                 cred_alloc = false;
 131                 // Needs the flag as it ignores a plain /rehash
 132                 OnModuleRehash(NULL,"ssl");
 133
 134                 // Void return, guess we assume success
 135                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 136                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept,
 137                         I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 138                         I_OnBufferFlushed, I_OnRequest, I_OnRehash, I_OnModuleRehash, I_OnPostConnect,
 139                         I_OnEvent, I_OnHookIO };
 140                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 141
 142                 ServerInstance->AddCommand(&starttls);
 143         }
 144
 145         virtual void OnRehash(User* user)
 146         {
 147                 ConfigReader Conf(ServerInstance);
 148
 149                 listenports.clear();
 150                 sslports.clear();
 151
 152                 for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 153                 {
 154                         ListenSocketBase* port = ServerInstance->ports[i];
 155                         std::string desc = port->GetDescription();
 156                         if (desc != "gnutls")
 157                                 continue;
 158
 159                         listenports.insert(port);
 160                         std::string portid = port->GetBindDesc();
 161
 162                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str());
 163                         if (port->GetIP() != "127.0.0.1")
 164                                 sslports.append(portid).append(";");
 165                 }
 166
 167                 if (!sslports.empty())
 168                         sslports.erase(sslports.end() - 1);
 169         }
 170
 171         virtual void OnModuleRehash(User* user, const std::string &param)
 172         {
 173                 if(param != "ssl")
 174                         return;
 175
 176                 OnRehash(user);
 177
 178                 ConfigReader Conf(ServerInstance);
 179
 180                 std::string confdir(ServerInstance->ConfigFileName);
 181                 // +1 so we the path ends with a /
 182                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 183
 184                 cafile = Conf.ReadValue("gnutls", "cafile", 0);
 185                 crlfile = Conf.ReadValue("gnutls", "crlfile", 0);
 186                 certfile = Conf.ReadValue("gnutls", "certfile", 0);
 187                 keyfile = Conf.ReadValue("gnutls", "keyfile", 0);
 188                 dh_bits = Conf.ReadInteger("gnutls", "dhbits", 0, false);
 189
 190                 // Set all the default values needed.
 191                 if (cafile.empty())
 192                         cafile = "ca.pem";
 193
 194                 if (crlfile.empty())
 195                         crlfile = "crl.pem";
 196
 197                 if (certfile.empty())
 198                         certfile = "cert.pem";
 199
 200                 if (keyfile.empty())
 201                         keyfile = "key.pem";
 202
 203                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 204                         dh_bits = 1024;
 205
 206                 // Prepend relative paths with the path to the config directory.
 207                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 208                         cafile = confdir + cafile;
 209
 210                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 211                         crlfile = confdir + crlfile;
 212
 213                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 214                         certfile = confdir + certfile;
 215
 216                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 217                         keyfile = confdir + keyfile;
 218
 219                 int ret;
 220
 221                 if (cred_alloc)
 222                 {
 223                         // Deallocate the old credentials
 224                         gnutls_dh_params_deinit(dh_params);
 225                         gnutls_certificate_free_credentials(x509_cred);
 226                 }
 227                 else
 228                         cred_alloc = true;
 229
 230                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 231                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 232
 233                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 234                         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));
 235
 236                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 237                         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));
 238
 239                 FileReader reader(ServerInstance);
 240
 241                 reader.LoadFile(certfile);
 242                 std::string cert_string = reader.Contents();
 243                 gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), cert_string.length() };
 244
 245                 reader.LoadFile(keyfile);
 246                 std::string key_string = reader.Contents();
 247                 gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), key_string.length() };
 248
 249                 // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 250                 if((ret = gnutls_x509_crt_import(x509_cert, &cert_datum, GNUTLS_X509_FMT_PEM)) < 0)
 251                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + std::string(gnutls_strerror(ret)));
 252
 253                 if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0)
 254                         throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret)));
 255
 256                 if((ret = gnutls_certificate_set_x509_key(x509_cred, &x509_cert, 1, x509_key)) < 0)
 257                         throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
 258
 259                 gnutls_certificate_client_set_retrieve_function (x509_cred, cert_callback);
 260
 261                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 262                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 263
 264                 // This may be on a large (once a day or week) timer eventually.
 265                 GenerateDHParams();
 266         }
 267
 268         void GenerateDHParams()
 269         {
 270                 // Generate Diffie Hellman parameters - for use with DHE
 271                 // kx algorithms. These should be discarded and regenerated
 272                 // once a day, once a week or once a month. Depending on the
 273                 // security requirements.
 274
 275                 int ret;
 276
 277                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 278                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 279         }
 280
 281         virtual ~ModuleSSLGnuTLS()
 282         {
 283                 gnutls_x509_crt_deinit(x509_cert);
 284                 gnutls_x509_privkey_deinit(x509_key);
 285                 gnutls_dh_params_deinit(dh_params);
 286                 gnutls_certificate_free_credentials(x509_cred);
 287                 gnutls_global_deinit();
 288                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 289                 delete[] sessions;
 290         }
 291
 292         virtual void OnCleanup(int target_type, void* item)
 293         {
 294                 if(target_type == TYPE_USER)
 295                 {
 296                         User* user = static_cast<User*>(item);
 297
 298                         if (user->GetIOHook() == this)
 299                         {
 300                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 301                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 302                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 303                                 user->DelIOHook();
 304                         }
 305                 }
 306         }
 307
 308         virtual Version GetVersion()
 309         {
 310                 return Version("$Id$", VF_VENDOR, API_VERSION);
 311         }
 312
 313
 314         virtual void On005Numeric(std::string &output)
 315         {
 316                 if (!sslports.empty())
 317                         output.append(" SSL=" + sslports);
 318                 output.append(" STARTTLS");
 319         }
 320
 321         virtual void OnHookIO(EventHandler* user, ListenSocketBase* lsb)
 322         {
 323                 if (!user->GetIOHook() && listenports.find(lsb) != listenports.end())
 324                 {
 325                         /* Hook the user with our module */
 326                         user->AddIOHook(this);
 327                 }
 328         }
 329
 330         virtual const char* OnRequest(Request* request)
 331         {
 332                 ISHRequest* ISR = static_cast<ISHRequest*>(request);
 333                 if (strcmp("IS_NAME", request->GetId()) == 0)
 334                 {
 335                         return "gnutls";
 336                 }
 337                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 338                 {
 339                         const char* ret = "OK";
 340                         try
 341                         {
 342                                 ret = ISR->Sock->AddIOHook(this) ? "OK" : NULL;
 343                         }
 344                         catch (ModuleException &e)
 345                         {
 346                                 return NULL;
 347                         }
 348                         return ret;
 349                 }
 350                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 351                 {
 352                         return ISR->Sock->DelIOHook() ? "OK" : NULL;
 353                 }
 354                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 355                 {
 356                         if (ISR->Sock->GetFd() < 0)
 357                                 return "OK";
 358
 359                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 360                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 361                 }
 362                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 363                 {
 364                         if (ISR->Sock->GetFd() > -1)
 365                         {
 366                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 367                                 if (session->sess)
 368                                 {
 369                                         if (static_cast<Extensible*>(ServerInstance->SE->GetRef(ISR->Sock->GetFd())) == static_cast<Extensible*>(ISR->Sock))
 370                                         {
 371                                                 return "OK";
 372                                         }
 373                                 }
 374                         }
 375                 }
 376                 else if (strcmp("GET_CERT", request->GetId()) == 0)
 377                 {
 378                         Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so");
 379                         if (sslinfo)
 380                                 return sslinfo->OnRequest(request);
 381                 }
 382                 return NULL;
 383         }
 384
 385
 386         virtual void OnRawSocketAccept(int fd, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 387         {
 388                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 389                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 390                         return;
 391
 392                 issl_session* session = &sessions[fd];
 393
 394                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 395                 if (session->sess)
 396                         return;
 397
 398                 gnutls_init(&session->sess, GNUTLS_SERVER);
 399
 400                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 401                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 402                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 403
 404                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(fd)); // Give gnutls the fd for the socket.
 405
 406                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 407
 408                 Handshake(session, fd);
 409         }
 410
 411         virtual void OnRawSocketConnect(int fd)
 412         {
 413                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 414                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 415                         return;
 416
 417                 issl_session* session = &sessions[fd];
 418
 419                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 420
 421                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 422                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 423                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 424                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(fd)); // Give gnutls the fd for the socket.
 425
 426                 Handshake(session, fd);
 427         }
 428
 429         virtual void OnRawSocketClose(int fd)
 430         {
 431                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 432                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 433                         return;
 434
 435                 CloseSession(&sessions[fd]);
 436         }
 437
 438         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 439         {
 440                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 441                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 442                         return 0;
 443
 444                 issl_session* session = &sessions[fd];
 445
 446                 if (!session->sess)
 447                 {
 448                         readresult = 0;
 449                         CloseSession(session);
 450                         return 1;
 451                 }
 452
 453                 if (session->status == ISSL_HANDSHAKING_READ)
 454                 {
 455                         // The handshake isn't finished, try to finish it.
 456
 457                         if(!Handshake(session, fd))
 458                         {
 459                                 errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 460                                 // Couldn't resume handshake.
 461                                 return -1;
 462                         }
 463                 }
 464                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 465                 {
 466                         errno = EAGAIN;
 467                         MakePollWrite(fd);
 468                         return -1;
 469                 }
 470
 471                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 472
 473                 if (session->status == ISSL_HANDSHAKEN)
 474                 {
 475                         unsigned int len = 0;
 476                         while (len < count)
 477                         {
 478                                 int ret = gnutls_record_recv(session->sess, buffer + len, count - len);
 479                                 if (ret > 0)
 480                                 {
 481                                         len += ret;
 482                                 }
 483                                 else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 484                                 {
 485                                         break;
 486                                 }
 487                                 else
 488                                 {
 489                                         if (ret != 0)
 490                                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 491                                                         "m_ssl_gnutls.so: Error while reading on fd %d: %s",
 492                                                         fd, gnutls_strerror(ret));
 493
 494                                         // if ret == 0, client closed connection.
 495                                         readresult = 0;
 496                                         CloseSession(session);
 497                                         return 1;
 498                                 }
 499                         }
 500                         readresult = len;
 501                         if (len)
 502                         {
 503                                 return 1;
 504                         }
 505                         else
 506                         {
 507                                 errno = EAGAIN;
 508                                 return -1;
 509                         }
 510                 }
 511                 else if (session->status == ISSL_CLOSING)
 512                         readresult = 0;
 513
 514                 return 1;
 515         }
 516
 517         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 518         {
 519                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 520                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 521                         return 0;
 522
 523                 issl_session* session = &sessions[fd];
 524                 const char* sendbuffer = buffer;
 525
 526                 if (!session->sess)
 527                 {
 528                         CloseSession(session);
 529                         return 1;
 530                 }
 531
 532                 session->outbuf.append(sendbuffer, count);
 533                 sendbuffer = session->outbuf.c_str();
 534                 count = session->outbuf.size();
 535
 536                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 537                 {
 538                         // The handshake isn't finished, try to finish it.
 539                         Handshake(session, fd);
 540                         errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 541                         return -1;
 542                 }
 543
 544                 int ret = 0;
 545
 546                 if (session->status == ISSL_HANDSHAKEN)
 547                 {
 548                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 549
 550                         if (ret == 0)
 551                         {
 552                                 CloseSession(session);
 553                         }
 554                         else if (ret < 0)
 555                         {
 556                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 557                                 {
 558                                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 559                                                         "m_ssl_gnutls.so: Error while writing to fd %d: %s",
 560                                                         fd, gnutls_strerror(ret));
 561                                         CloseSession(session);
 562                                 }
 563                                 else
 564                                 {
 565                                         errno = EAGAIN;
 566                                 }
 567                         }
 568                         else
 569                         {
 570                                 session->outbuf = session->outbuf.substr(ret);
 571                         }
 572                 }
 573
 574                 if (!session->outbuf.empty())
 575                         MakePollWrite(fd);
 576
 577                 /* Who's smart idea was it to return 1 when we havent written anything?
 578                  * This fucks the buffer up in BufferedSocket :p
 579                  */
 580                 return ret < 1 ? 0 : ret;
 581         }
 582
 583         bool Handshake(issl_session* session, int fd)
 584         {
 585                 int ret = gnutls_handshake(session->sess);
 586
 587                 if (ret < 0)
 588                 {
 589                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 590                         {
 591                                 // Handshake needs resuming later, read() or write() would have blocked.
 592
 593                                 if(gnutls_record_get_direction(session->sess) == 0)
 594                                 {
 595                                         // gnutls_handshake() wants to read() again.
 596                                         session->status = ISSL_HANDSHAKING_READ;
 597                                 }
 598                                 else
 599                                 {
 600                                         // gnutls_handshake() wants to write() again.
 601                                         session->status = ISSL_HANDSHAKING_WRITE;
 602                                         MakePollWrite(fd);
 603                                 }
 604                         }
 605                         else
 606                         {
 607                                 // Handshake failed.
 608                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 609                                                 "m_ssl_gnutls.so: Handshake failed on fd %d: %s",
 610                                                 fd, gnutls_strerror(ret));
 611                                 CloseSession(session);
 612                                 session->status = ISSL_CLOSING;
 613                         }
 614
 615                         return false;
 616                 }
 617                 else
 618                 {
 619                         // Change the seesion state
 620                         session->status = ISSL_HANDSHAKEN;
 621
 622                         EventHandler* user = ServerInstance->SE->GetRef(fd);
 623
 624                         VerifyCertificate(session,user);
 625
 626                         // Finish writing, if any left
 627                         MakePollWrite(fd);
 628
 629                         return true;
 630                 }
 631         }
 632
 633         virtual void OnPostConnect(User* user)
 634         {
 635                 // This occurs AFTER OnUserConnect so we can be sure the
 636                 // protocol module has propagated the NICK message.
 637                 if (user->GetIOHook() == this && (IS_LOCAL(user)))
 638                 {
 639                         if (sessions[user->GetFd()].sess)
 640                         {
 641                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 642                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 643                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 644                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 645                         }
 646                 }
 647         }
 648
 649         void MakePollWrite(int fd)
 650         {
 651                 //OnRawSocketWrite(fd, NULL, 0);
 652                 EventHandler* eh = ServerInstance->SE->GetRef(fd);
 653                 if (eh)
 654                         ServerInstance->SE->WantWrite(eh);
 655         }
 656
 657         virtual void OnBufferFlushed(User* user)
 658         {
 659                 if (user->GetIOHook() == this)
 660                 {
 661                         issl_session* session = &sessions[user->GetFd()];
 662                         if (session && session->outbuf.size())
 663                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 664                 }
 665         }
 666
 667         void CloseSession(issl_session* session)
 668         {
 669                 if(session->sess)
 670                 {
 671                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 672                         gnutls_deinit(session->sess);
 673                 }
 674
 675                 session->outbuf.clear();
 676                 session->sess = NULL;
 677                 session->status = ISSL_NONE;
 678         }
 679
 680         void VerifyCertificate(issl_session* session, Extensible* user)
 681         {
 682                 if (!session->sess || !user)
 683                         return;
 684
 685                 Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so");
 686                 if (!sslinfo)
 687                         return;
 688
 689                 unsigned int status;
 690                 const gnutls_datum_t* cert_list;
 691                 int ret;
 692                 unsigned int cert_list_size;
 693                 gnutls_x509_crt_t cert;
 694                 char name[MAXBUF];
 695                 unsigned char digest[MAXBUF];
 696                 size_t digest_size = sizeof(digest);
 697                 size_t name_size = sizeof(name);
 698                 ssl_cert* certinfo = new ssl_cert;
 699
 700                 /* This verification function uses the trusted CAs in the credentials
 701                  * structure. So you must have installed one or more CA certificates.
 702                  */
 703                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 704
 705                 if (ret < 0)
 706                 {
 707                         certinfo->error = std::string(gnutls_strerror(ret));
 708                         goto info_done;
 709                 }
 710
 711                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 712                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 713                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 714                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 715
 716                 /* Up to here the process is the same for X.509 certificates and
 717                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 718                  * be easily extended to work with openpgp keys as well.
 719                  */
 720                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 721                 {
 722                         certinfo->error = "No X509 keys sent";
 723                         goto info_done;
 724                 }
 725
 726                 ret = gnutls_x509_crt_init(&cert);
 727                 if (ret < 0)
 728                 {
 729                         certinfo->error = gnutls_strerror(ret);
 730                         goto info_done;
 731                 }
 732
 733                 cert_list_size = 0;
 734                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 735                 if (cert_list == NULL)
 736                 {
 737                         certinfo->error = "No certificate was found";
 738                         goto info_done_dealloc;
 739                 }
 740
 741                 /* This is not a real world example, since we only check the first
 742                  * certificate in the given chain.
 743                  */
 744
 745                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 746                 if (ret < 0)
 747                 {
 748                         certinfo->error = gnutls_strerror(ret);
 749                         goto info_done_dealloc;
 750                 }
 751
 752                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 753                 certinfo->dn = name;
 754
 755                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 756                 certinfo->issuer = name;
 757
 758                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 759                 {
 760                         certinfo->error = gnutls_strerror(ret);
 761                 }
 762                 else
 763                 {
 764                         certinfo->fingerprint = irc::hex(digest, digest_size);
 765                 }
 766
 767                 /* Beware here we do not check for errors.
 768                  */
 769                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 770                 {
 771                         certinfo->error = "Not activated, or expired certificate";
 772                 }
 773
 774 info_done_dealloc:
 775                 gnutls_x509_crt_deinit(cert);
 776 info_done:
 777                 BufferedSocketFingerprintSubmission(user, this, sslinfo, certinfo).Send();
 778         }
 779
 780         void OnEvent(Event* ev)
 781         {
 782                 capHandler.HandleEvent(ev);
 783         }
 784 };
 785
 786 MODULE_INIT(ModuleSSLGnuTLS)