src/modules/extra/m_ssl_gnutls.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2010 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 <gcrypt.h>
  18 #include "ssl.h"
  19 #include "m_cap.h"
  20
  21 #ifdef WINDOWS
  22 #pragma comment(lib, "libgnutls-13.lib")
  23 #endif
  24
  25 /* $ModDesc: Provides SSL support for clients */
  26 /* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") */
  27 /* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") */
  28
  29 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  30
  31 static gnutls_x509_crt_t x509_cert;
  32 static gnutls_x509_privkey_t x509_key;
  33 static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs,
  34         const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr_st * st) {
  35
  36         st->type = GNUTLS_CRT_X509;
  37         st->ncerts = 1;
  38         st->cert.x509 = &x509_cert;
  39         st->key.x509 = x509_key;
  40         st->deinit_all = 0;
  41
  42         return 0;
  43 }
  44
  45 static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t user_wrap, void* buffer, size_t size)
  46 {
  47         StreamSocket* user = reinterpret_cast<StreamSocket*>(user_wrap);
  48         if (user->GetEventMask() & FD_READ_WILL_BLOCK)
  49         {
  50                 errno = EAGAIN;
  51                 return -1;
  52         }
  53         int rv = recv(user->GetFd(), buffer, size, 0);
  54         if (rv < (int)size)
  55                 ServerInstance->SE->ChangeEventMask(user, FD_READ_WILL_BLOCK);
  56         return rv;
  57 }
  58
  59 static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t user_wrap, const void* buffer, size_t size)
  60 {
  61         StreamSocket* user = reinterpret_cast<StreamSocket*>(user_wrap);
  62         if (user->GetEventMask() & FD_WRITE_WILL_BLOCK)
  63         {
  64                 errno = EAGAIN;
  65                 return -1;
  66         }
  67         int rv = send(user->GetFd(), buffer, size, 0);
  68         if (rv < (int)size)
  69                 ServerInstance->SE->ChangeEventMask(user, FD_WRITE_WILL_BLOCK);
  70         return rv;
  71 }
  72
  73 class RandGen : public HandlerBase2<void, char*, size_t>
  74 {
  75  public:
  76         RandGen() {}
  77         void Call(char* buffer, size_t len)
  78         {
  79                 gcry_randomize(buffer, len, GCRY_STRONG_RANDOM);
  80         }
  81 };
  82
  83 /** Represents an SSL user's extra data
  84  */
  85 class issl_session
  86 {
  87 public:
  88         gnutls_session_t sess;
  89         issl_status status;
  90         reference<ssl_cert> cert;
  91         issl_session() : sess(NULL) {}
  92 };
  93
  94 class CommandStartTLS : public SplitCommand
  95 {
  96  public:
  97         CommandStartTLS (Module* mod) : SplitCommand(mod, "STARTTLS")
  98         {
  99                 works_before_reg = true;
 100         }
 101
 102         CmdResult HandleLocal(const std::vector<std::string> &parameters, LocalUser *user)
 103         {
 104                 /* changed from == REG_ALL to catch clients sending STARTTLS
 105                  * after NICK and USER but before OnUserConnect completes and
 106                  * give a proper error message (see bug #645) - dz
 107                  */
 108                 if (user->registered != REG_NONE)
 109                 {
 110                         user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration has started", user->nick.c_str());
 111                 }
 112                 else
 113                 {
 114                         if (!user->eh.GetIOHook())
 115                         {
 116                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
 117                                 /* We need to flush the write buffer prior to adding the IOHook,
 118                                  * otherwise we'll be sending this line inside the SSL session - which
 119                                  * won't start its handshake until the client gets this line. Currently,
 120                                  * we assume the write will not block here; this is usually safe, as
 121                                  * STARTTLS is sent very early on in the registration phase, where the
 122                                  * user hasn't built up much sendq. Handling a blocked write here would
 123                                  * be very annoying.
 124                                  */
 125                                 user->eh.DoWrite();
 126                                 user->eh.AddIOHook(creator);
 127                                 creator->OnStreamSocketAccept(&user->eh, NULL, NULL);
 128                         }
 129                         else
 130                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
 131                 }
 132
 133                 return CMD_FAILURE;
 134         }
 135 };
 136
 137 class ModuleSSLGnuTLS : public Module
 138 {
 139         issl_session* sessions;
 140
 141         gnutls_certificate_credentials x509_cred;
 142         gnutls_dh_params dh_params;
 143         gnutls_digest_algorithm_t hash;
 144
 145         std::string sslports;
 146         int dh_bits;
 147
 148         bool cred_alloc;
 149
 150         RandGen randhandler;
 151         CommandStartTLS starttls;
 152
 153         GenericCap capHandler;
 154         ServiceProvider iohook;
 155  public:
 156
 157         ModuleSSLGnuTLS()
 158                 : starttls(this), capHandler(this, "tls"), iohook(this, "ssl/gnutls", SERVICE_IOHOOK)
 159         {
 160                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 161
 162                 gnutls_global_init(); // This must be called once in the program
 163                 gnutls_x509_crt_init(&x509_cert);
 164                 gnutls_x509_privkey_init(&x509_key);
 165
 166                 cred_alloc = false;
 167         }
 168
 169         void init()
 170         {
 171                 // Needs the flag as it ignores a plain /rehash
 172                 OnModuleRehash(NULL,"ssl");
 173
 174                 ServerInstance->GenRandom = &randhandler;
 175
 176                 // Void return, guess we assume success
 177                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 178                 Implementation eventlist[] = { I_On005Numeric, I_OnRehash, I_OnModuleRehash, I_OnUserConnect,
 179                         I_OnEvent, I_OnHookIO };
 180                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 181
 182                 ServerInstance->Modules->AddService(iohook);
 183                 ServerInstance->AddCommand(&starttls);
 184         }
 185
 186         void OnRehash(User* user)
 187         {
 188                 sslports.clear();
 189
 190                 for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 191                 {
 192                         ListenSocket* port = ServerInstance->ports[i];
 193                         if (port->bind_tag->getString("ssl") != "gnutls")
 194                                 continue;
 195
 196                         const std::string& portid = port->bind_desc;
 197                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str());
 198
 199                         if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
 200                                 sslports.append(portid).append(";");
 201                 }
 202
 203                 if (!sslports.empty())
 204                         sslports.erase(sslports.end() - 1);
 205         }
 206
 207         void OnModuleRehash(User* user, const std::string &param)
 208         {
 209                 if(param != "ssl")
 210                         return;
 211
 212                 std::string keyfile;
 213                 std::string certfile;
 214                 std::string cafile;
 215                 std::string crlfile;
 216                 OnRehash(user);
 217
 218                 ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
 219
 220                 cafile = Conf->getString("cafile", "conf/ca.pem");
 221                 crlfile = Conf->getString("crlfile", "conf/crl.pem");
 222                 certfile = Conf->getString("certfile", "conf/cert.pem");
 223                 keyfile = Conf->getString("keyfile", "conf/key.pem");
 224                 dh_bits = Conf->getInt("dhbits");
 225                 std::string hashname = Conf->getString("hash", "md5");
 226
 227                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 228                         dh_bits = 1024;
 229
 230                 if (hashname == "md5")
 231                         hash = GNUTLS_DIG_MD5;
 232                 else if (hashname == "sha1")
 233                         hash = GNUTLS_DIG_SHA1;
 234                 else
 235                         throw ModuleException("Unknown hash type " + hashname);
 236
 237
 238                 int ret;
 239
 240                 if (cred_alloc)
 241                 {
 242                         // Deallocate the old credentials
 243                         gnutls_dh_params_deinit(dh_params);
 244                         gnutls_certificate_free_credentials(x509_cred);
 245                 }
 246                 else
 247                         cred_alloc = true;
 248
 249                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 250                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 251
 252                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 253                         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));
 254
 255                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 256                         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));
 257
 258                 FileReader reader;
 259
 260                 reader.LoadFile(certfile);
 261                 std::string cert_string = reader.Contents();
 262                 gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), cert_string.length() };
 263
 264                 reader.LoadFile(keyfile);
 265                 std::string key_string = reader.Contents();
 266                 gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), key_string.length() };
 267
 268                 // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 269                 if((ret = gnutls_x509_crt_import(x509_cert, &cert_datum, GNUTLS_X509_FMT_PEM)) < 0)
 270                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + std::string(gnutls_strerror(ret)));
 271
 272                 if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0)
 273                         throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret)));
 274
 275                 if((ret = gnutls_certificate_set_x509_key(x509_cred, &x509_cert, 1, x509_key)) < 0)
 276                         throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
 277
 278                 gnutls_certificate_client_set_retrieve_function (x509_cred, cert_callback);
 279
 280                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 281                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 282
 283                 // This may be on a large (once a day or week) timer eventually.
 284                 GenerateDHParams();
 285         }
 286
 287         void GenerateDHParams()
 288         {
 289                 // Generate Diffie Hellman parameters - for use with DHE
 290                 // kx algorithms. These should be discarded and regenerated
 291                 // once a day, once a week or once a month. Depending on the
 292                 // security requirements.
 293
 294                 int ret;
 295
 296                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 297                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 298         }
 299
 300         ~ModuleSSLGnuTLS()
 301         {
 302                 gnutls_x509_crt_deinit(x509_cert);
 303                 gnutls_x509_privkey_deinit(x509_key);
 304                 if (cred_alloc)
 305                 {
 306                         gnutls_dh_params_deinit(dh_params);
 307                         gnutls_certificate_free_credentials(x509_cred);
 308                 }
 309                 gnutls_global_deinit();
 310                 delete[] sessions;
 311                 ServerInstance->GenRandom = &ServerInstance->HandleGenRandom;
 312         }
 313
 314         void OnCleanup(int target_type, void* item)
 315         {
 316                 if(target_type == TYPE_USER)
 317                 {
 318                         LocalUser* user = IS_LOCAL(static_cast<User*>(item));
 319
 320                         if (user && user->eh.GetIOHook() == this)
 321                         {
 322                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 323                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 324                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 325                         }
 326                 }
 327         }
 328
 329         Version GetVersion()
 330         {
 331                 return Version("Provides SSL support for clients", VF_VENDOR);
 332         }
 333
 334
 335         void On005Numeric(std::string &output)
 336         {
 337                 if (!sslports.empty())
 338                         output.append(" SSL=" + sslports);
 339                 output.append(" STARTTLS");
 340         }
 341
 342         void OnHookIO(StreamSocket* user, ListenSocket* lsb)
 343         {
 344                 if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "gnutls")
 345                 {
 346                         /* Hook the user with our module */
 347                         user->AddIOHook(this);
 348                 }
 349         }
 350
 351         void OnRequest(Request& request)
 352         {
 353                 if (strcmp("GET_SSL_CERT", request.id) == 0)
 354                 {
 355                         SocketCertificateRequest& req = static_cast<SocketCertificateRequest&>(request);
 356                         int fd = req.sock->GetFd();
 357                         issl_session* session = &sessions[fd];
 358
 359                         req.cert = session->cert;
 360                 }
 361         }
 362
 363         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 364         {
 365                 int fd = user->GetFd();
 366                 issl_session* session = &sessions[fd];
 367
 368                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 369                 if (session->sess)
 370                         return;
 371
 372                 gnutls_init(&session->sess, GNUTLS_SERVER);
 373
 374                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 375                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 376                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 377
 378                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
 379                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 380                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 381
 382                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 383
 384                 Handshake(session, user);
 385         }
 386
 387         void OnStreamSocketConnect(StreamSocket* user)
 388         {
 389                 issl_session* session = &sessions[user->GetFd()];
 390
 391                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 392
 393                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 394                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 395                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 396                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
 397                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 398                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 399
 400                 Handshake(session, user);
 401         }
 402
 403         void OnStreamSocketClose(StreamSocket* user)
 404         {
 405                 CloseSession(&sessions[user->GetFd()]);
 406         }
 407
 408         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 409         {
 410                 issl_session* session = &sessions[user->GetFd()];
 411
 412                 if (!session->sess)
 413                 {
 414                         CloseSession(session);
 415                         user->SetError("No SSL session");
 416                         return -1;
 417                 }
 418
 419                 if (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE)
 420                 {
 421                         // The handshake isn't finished, try to finish it.
 422
 423                         if(!Handshake(session, user))
 424                         {
 425                                 if (session->status != ISSL_CLOSING)
 426                                         return 0;
 427                                 return -1;
 428                         }
 429                 }
 430
 431                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 432
 433                 if (session->status == ISSL_HANDSHAKEN)
 434                 {
 435                         char* buffer = ServerInstance->GetReadBuffer();
 436                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 437                         int ret = gnutls_record_recv(session->sess, buffer, bufsiz);
 438                         if (ret > 0)
 439                         {
 440                                 recvq.append(buffer, ret);
 441                                 return 1;
 442                         }
 443                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 444                         {
 445                                 return 0;
 446                         }
 447                         else if (ret == 0)
 448                         {
 449                                 user->SetError("SSL Connection closed");
 450                                 CloseSession(session);
 451                                 return -1;
 452                         }
 453                         else
 454                         {
 455                                 user->SetError(gnutls_strerror(ret));
 456                                 CloseSession(session);
 457                                 return -1;
 458                         }
 459                 }
 460                 else if (session->status == ISSL_CLOSING)
 461                         return -1;
 462
 463                 return 0;
 464         }
 465
 466         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 467         {
 468                 issl_session* session = &sessions[user->GetFd()];
 469
 470                 if (!session->sess)
 471                 {
 472                         CloseSession(session);
 473                         user->SetError("No SSL session");
 474                         return -1;
 475                 }
 476
 477                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 478                 {
 479                         // The handshake isn't finished, try to finish it.
 480                         Handshake(session, user);
 481                         if (session->status != ISSL_CLOSING)
 482                                 return 0;
 483                         return -1;
 484                 }
 485
 486                 int ret = 0;
 487
 488                 if (session->status == ISSL_HANDSHAKEN)
 489                 {
 490                         ret = gnutls_record_send(session->sess, sendq.data(), sendq.length());
 491
 492                         if (ret == (int)sendq.length())
 493                         {
 494                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE);
 495                                 return 1;
 496                         }
 497                         else if (ret > 0)
 498                         {
 499                                 sendq = sendq.substr(ret);
 500                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 501                                 return 0;
 502                         }
 503                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 504                         {
 505                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 506                                 return 0;
 507                         }
 508                         else if (ret == 0)
 509                         {
 510                                 CloseSession(session);
 511                                 user->SetError("SSL Connection closed");
 512                                 return -1;
 513                         }
 514                         else // (ret < 0)
 515                         {
 516                                 user->SetError(gnutls_strerror(ret));
 517                                 CloseSession(session);
 518                                 return -1;
 519                         }
 520                 }
 521
 522                 return 0;
 523         }
 524
 525         bool Handshake(issl_session* session, StreamSocket* user)
 526         {
 527                 int ret = gnutls_handshake(session->sess);
 528
 529                 if (ret < 0)
 530                 {
 531                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 532                         {
 533                                 // Handshake needs resuming later, read() or write() would have blocked.
 534
 535                                 if(gnutls_record_get_direction(session->sess) == 0)
 536                                 {
 537                                         // gnutls_handshake() wants to read() again.
 538                                         session->status = ISSL_HANDSHAKING_READ;
 539                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 540                                 }
 541                                 else
 542                                 {
 543                                         // gnutls_handshake() wants to write() again.
 544                                         session->status = ISSL_HANDSHAKING_WRITE;
 545                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 546                                 }
 547                         }
 548                         else
 549                         {
 550                                 user->SetError(std::string("Handshake Failed - ") + gnutls_strerror(ret));
 551                                 CloseSession(session);
 552                                 session->status = ISSL_CLOSING;
 553                         }
 554
 555                         return false;
 556                 }
 557                 else
 558                 {
 559                         // Change the seesion state
 560                         session->status = ISSL_HANDSHAKEN;
 561
 562                         VerifyCertificate(session,user);
 563
 564                         // Finish writing, if any left
 565                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 566
 567                         return true;
 568                 }
 569         }
 570
 571         void OnUserConnect(LocalUser* user)
 572         {
 573                 if (user->eh.GetIOHook() == this)
 574                 {
 575                         if (sessions[user->eh.GetFd()].sess)
 576                         {
 577                                 ssl_cert* cert = sessions[user->eh.GetFd()].cert;
 578                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->eh.GetFd()].sess));
 579                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->eh.GetFd()].sess))).append("-");
 580                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->eh.GetFd()].sess)));
 581                                 if (cert->fingerprint.empty())
 582                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 583                                 else
 584                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\""
 585                                                 " and your SSL fingerprint is %s", user->nick.c_str(), cipher.c_str(), cert->fingerprint.c_str());
 586                         }
 587                 }
 588         }
 589
 590         void CloseSession(issl_session* session)
 591         {
 592                 if (session->sess)
 593                 {
 594                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 595                         gnutls_deinit(session->sess);
 596                 }
 597                 session->sess = NULL;
 598                 session->cert = NULL;
 599                 session->status = ISSL_NONE;
 600         }
 601
 602         void VerifyCertificate(issl_session* session, StreamSocket* user)
 603         {
 604                 if (!session->sess || !user || session->cert)
 605                         return;
 606
 607                 unsigned int status;
 608                 const gnutls_datum_t* cert_list;
 609                 int ret;
 610                 unsigned int cert_list_size;
 611                 gnutls_x509_crt_t cert;
 612                 char name[MAXBUF];
 613                 unsigned char digest[MAXBUF];
 614                 size_t digest_size = sizeof(digest);
 615                 size_t name_size = sizeof(name);
 616                 ssl_cert* certinfo = new ssl_cert;
 617                 session->cert = certinfo;
 618
 619                 /* This verification function uses the trusted CAs in the credentials
 620                  * structure. So you must have installed one or more CA certificates.
 621                  */
 622                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 623
 624                 if (ret < 0)
 625                 {
 626                         certinfo->error = std::string(gnutls_strerror(ret));
 627                         return;
 628                 }
 629
 630                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 631                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 632                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 633                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 634
 635                 /* Up to here the process is the same for X.509 certificates and
 636                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 637                  * be easily extended to work with openpgp keys as well.
 638                  */
 639                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 640                 {
 641                         certinfo->error = "No X509 keys sent";
 642                         return;
 643                 }
 644
 645                 ret = gnutls_x509_crt_init(&cert);
 646                 if (ret < 0)
 647                 {
 648                         certinfo->error = gnutls_strerror(ret);
 649                         return;
 650                 }
 651
 652                 cert_list_size = 0;
 653                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 654                 if (cert_list == NULL)
 655                 {
 656                         certinfo->error = "No certificate was found";
 657                         goto info_done_dealloc;
 658                 }
 659
 660                 /* This is not a real world example, since we only check the first
 661                  * certificate in the given chain.
 662                  */
 663
 664                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 665                 if (ret < 0)
 666                 {
 667                         certinfo->error = gnutls_strerror(ret);
 668                         goto info_done_dealloc;
 669                 }
 670
 671                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 672                 certinfo->dn = name;
 673
 674                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 675                 certinfo->issuer = name;
 676
 677                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, hash, digest, &digest_size)) < 0)
 678                 {
 679                         certinfo->error = gnutls_strerror(ret);
 680                 }
 681                 else
 682                 {
 683                         certinfo->fingerprint = irc::hex(digest, digest_size);
 684                 }
 685
 686                 /* Beware here we do not check for errors.
 687                  */
 688                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 689                 {
 690                         certinfo->error = "Not activated, or expired certificate";
 691                 }
 692
 693 info_done_dealloc:
 694                 gnutls_x509_crt_deinit(cert);
 695         }
 696
 697         void OnEvent(Event& ev)
 698         {
 699                 capHandler.HandleEvent(ev);
 700         }
 701 };
 702
 703 MODULE_INIT(ModuleSSLGnuTLS)