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 "ssl.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 /* $CopyInstall: conf/key.pem $(CONPATH) -m 0400 -o $(INSTUID) */
  28 /* $CopyInstall: conf/cert.pem $(CONPATH) -m 0444 */
  29
  30 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  31
  32 static gnutls_x509_crt_t x509_cert;
  33 static gnutls_x509_privkey_t x509_key;
  34 static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs,
  35         const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr_st * st) {
  36
  37         st->type = GNUTLS_CRT_X509;
  38         st->ncerts = 1;
  39         st->cert.x509 = &x509_cert;
  40         st->key.x509 = x509_key;
  41         st->deinit_all = 0;
  42
  43         return 0;
  44 }
  45
  46 static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t user_wrap, void* buffer, size_t size)
  47 {
  48         StreamSocket* user = reinterpret_cast<StreamSocket*>(user_wrap);
  49         if (user->GetEventMask() & FD_READ_WILL_BLOCK)
  50         {
  51                 errno = EAGAIN;
  52                 return -1;
  53         }
  54         int rv = recv(user->GetFd(), buffer, size, 0);
  55         if (rv < (int)size)
  56                 ServerInstance->SE->ChangeEventMask(user, FD_READ_WILL_BLOCK);
  57         return rv;
  58 }
  59
  60 static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t user_wrap, const void* buffer, size_t size)
  61 {
  62         StreamSocket* user = reinterpret_cast<StreamSocket*>(user_wrap);
  63         if (user->GetEventMask() & FD_WRITE_WILL_BLOCK)
  64         {
  65                 errno = EAGAIN;
  66                 return -1;
  67         }
  68         int rv = send(user->GetFd(), buffer, size, 0);
  69         if (rv < (int)size)
  70                 ServerInstance->SE->ChangeEventMask(user, FD_WRITE_WILL_BLOCK);
  71         return rv;
  72 }
  73
  74 /** Represents an SSL user's extra data
  75  */
  76 class issl_session
  77 {
  78 public:
  79         gnutls_session_t sess;
  80         issl_status status;
  81         reference<ssl_cert> cert;
  82         issl_session() : sess(NULL) {}
  83 };
  84
  85 class CommandStartTLS : public SplitCommand
  86 {
  87  public:
  88         CommandStartTLS (Module* mod) : SplitCommand(mod, "STARTTLS")
  89         {
  90                 works_before_reg = true;
  91         }
  92
  93         CmdResult HandleLocal(const std::vector<std::string> &parameters, LocalUser *user)
  94         {
  95                 /* changed from == REG_ALL to catch clients sending STARTTLS
  96                  * after NICK and USER but before OnUserConnect completes and
  97                  * give a proper error message (see bug #645) - dz
  98                  */
  99                 if (user->registered != REG_NONE)
 100                 {
 101                         user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration has started", user->nick.c_str());
 102                 }
 103                 else
 104                 {
 105                         if (!user->eh.GetIOHook())
 106                         {
 107                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
 108                                 /* We need to flush the write buffer prior to adding the IOHook,
 109                                  * otherwise we'll be sending this line inside the SSL session - which
 110                                  * won't start its handshake until the client gets this line. Currently,
 111                                  * we assume the write will not block here; this is usually safe, as
 112                                  * STARTTLS is sent very early on in the registration phase, where the
 113                                  * user hasn't built up much sendq. Handling a blocked write here would
 114                                  * be very annoying.
 115                                  */
 116                                 user->eh.DoWrite();
 117                                 user->eh.AddIOHook(creator);
 118                                 creator->OnStreamSocketAccept(&user->eh, NULL, NULL);
 119                         }
 120                         else
 121                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
 122                 }
 123
 124                 return CMD_FAILURE;
 125         }
 126 };
 127
 128 class ModuleSSLGnuTLS : public Module
 129 {
 130         issl_session* sessions;
 131
 132         gnutls_certificate_credentials x509_cred;
 133         gnutls_dh_params dh_params;
 134         gnutls_digest_algorithm_t hash;
 135
 136         std::string sslports;
 137         int dh_bits;
 138
 139         bool cred_alloc;
 140
 141         CommandStartTLS starttls;
 142
 143         GenericCap capHandler;
 144         ServiceProvider iohook;
 145  public:
 146
 147         ModuleSSLGnuTLS()
 148                 : starttls(this), capHandler(this, "tls"), iohook(this, "ssl/gnutls", SERVICE_IOHOOK)
 149         {
 150                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 151
 152                 gnutls_global_init(); // This must be called once in the program
 153                 gnutls_x509_crt_init(&x509_cert);
 154                 gnutls_x509_privkey_init(&x509_key);
 155
 156                 cred_alloc = false;
 157         }
 158
 159         void init()
 160         {
 161                 // Needs the flag as it ignores a plain /rehash
 162                 OnModuleRehash(NULL,"ssl");
 163
 164                 // Void return, guess we assume success
 165                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 166                 Implementation eventlist[] = { I_On005Numeric, I_OnRehash, I_OnModuleRehash, I_OnUserConnect,
 167                         I_OnEvent, I_OnHookIO };
 168                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 169
 170                 ServerInstance->Modules->AddService(iohook);
 171                 ServerInstance->AddCommand(&starttls);
 172         }
 173
 174         void OnRehash(User* user)
 175         {
 176                 sslports.clear();
 177
 178                 for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 179                 {
 180                         ListenSocket* port = ServerInstance->ports[i];
 181                         if (port->bind_tag->getString("ssl") != "gnutls")
 182                                 continue;
 183
 184                         const std::string& portid = port->bind_desc;
 185                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str());
 186
 187                         if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
 188                                 sslports.append(portid).append(";");
 189                 }
 190
 191                 if (!sslports.empty())
 192                         sslports.erase(sslports.end() - 1);
 193         }
 194
 195         void OnModuleRehash(User* user, const std::string &param)
 196         {
 197                 if(param != "ssl")
 198                         return;
 199
 200                 std::string keyfile;
 201                 std::string certfile;
 202                 std::string cafile;
 203                 std::string crlfile;
 204                 OnRehash(user);
 205
 206                 ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
 207
 208                 cafile = Conf->getString("cafile", "conf/ca.pem");
 209                 crlfile = Conf->getString("crlfile", "conf/crl.pem");
 210                 certfile = Conf->getString("certfile", "conf/cert.pem");
 211                 keyfile = Conf->getString("keyfile", "conf/key.pem");
 212                 dh_bits = Conf->getInt("dhbits");
 213                 std::string hashname = Conf->getString("hash", "md5");
 214
 215                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 216                         dh_bits = 1024;
 217
 218                 if (hashname == "md5")
 219                         hash = GNUTLS_DIG_MD5;
 220                 else if (hashname == "sha1")
 221                         hash = GNUTLS_DIG_SHA1;
 222                 else
 223                         throw ModuleException("Unknown hash type " + hashname);
 224
 225
 226                 int ret;
 227
 228                 if (cred_alloc)
 229                 {
 230                         // Deallocate the old credentials
 231                         gnutls_dh_params_deinit(dh_params);
 232                         gnutls_certificate_free_credentials(x509_cred);
 233                 }
 234                 else
 235                         cred_alloc = true;
 236
 237                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 238                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 239
 240                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 241                         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));
 242
 243                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 244                         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));
 245
 246                 FileReader reader;
 247
 248                 reader.LoadFile(certfile);
 249                 std::string cert_string = reader.Contents();
 250                 gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), cert_string.length() };
 251
 252                 reader.LoadFile(keyfile);
 253                 std::string key_string = reader.Contents();
 254                 gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), key_string.length() };
 255
 256                 // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 257                 if((ret = gnutls_x509_crt_import(x509_cert, &cert_datum, GNUTLS_X509_FMT_PEM)) < 0)
 258                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + std::string(gnutls_strerror(ret)));
 259
 260                 if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0)
 261                         throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret)));
 262
 263                 if((ret = gnutls_certificate_set_x509_key(x509_cred, &x509_cert, 1, x509_key)) < 0)
 264                         throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
 265
 266                 gnutls_certificate_client_set_retrieve_function (x509_cred, cert_callback);
 267
 268                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 269                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 270
 271                 // This may be on a large (once a day or week) timer eventually.
 272                 GenerateDHParams();
 273         }
 274
 275         void GenerateDHParams()
 276         {
 277                 // Generate Diffie Hellman parameters - for use with DHE
 278                 // kx algorithms. These should be discarded and regenerated
 279                 // once a day, once a week or once a month. Depending on the
 280                 // security requirements.
 281
 282                 int ret;
 283
 284                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 285                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 286         }
 287
 288         ~ModuleSSLGnuTLS()
 289         {
 290                 gnutls_x509_crt_deinit(x509_cert);
 291                 gnutls_x509_privkey_deinit(x509_key);
 292                 if (cred_alloc)
 293                 {
 294                         gnutls_dh_params_deinit(dh_params);
 295                         gnutls_certificate_free_credentials(x509_cred);
 296                 }
 297                 gnutls_global_deinit();
 298                 delete[] sessions;
 299         }
 300
 301         void OnCleanup(int target_type, void* item)
 302         {
 303                 if(target_type == TYPE_USER)
 304                 {
 305                         LocalUser* user = IS_LOCAL(static_cast<User*>(item));
 306
 307                         if (user && user->eh.GetIOHook() == this)
 308                         {
 309                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 310                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 311                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 312                         }
 313                 }
 314         }
 315
 316         Version GetVersion()
 317         {
 318                 return Version("Provides SSL support for clients", VF_VENDOR);
 319         }
 320
 321
 322         void On005Numeric(std::string &output)
 323         {
 324                 if (!sslports.empty())
 325                         output.append(" SSL=" + sslports);
 326                 output.append(" STARTTLS");
 327         }
 328
 329         void OnHookIO(StreamSocket* user, ListenSocket* lsb)
 330         {
 331                 if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "gnutls")
 332                 {
 333                         /* Hook the user with our module */
 334                         user->AddIOHook(this);
 335                 }
 336         }
 337
 338         void OnRequest(Request& request)
 339         {
 340                 if (strcmp("GET_SSL_CERT", request.id) == 0)
 341                 {
 342                         SocketCertificateRequest& req = static_cast<SocketCertificateRequest&>(request);
 343                         int fd = req.sock->GetFd();
 344                         issl_session* session = &sessions[fd];
 345
 346                         req.cert = session->cert;
 347                 }
 348         }
 349
 350         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 351         {
 352                 int fd = user->GetFd();
 353                 issl_session* session = &sessions[fd];
 354
 355                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 356                 if (session->sess)
 357                         return;
 358
 359                 gnutls_init(&session->sess, GNUTLS_SERVER);
 360
 361                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 362                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 363                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 364
 365                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
 366                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 367                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 368
 369                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 370
 371                 Handshake(session, user);
 372         }
 373
 374         void OnStreamSocketConnect(StreamSocket* user)
 375         {
 376                 issl_session* session = &sessions[user->GetFd()];
 377
 378                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 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                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
 384                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 385                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 386
 387                 Handshake(session, user);
 388         }
 389
 390         void OnStreamSocketClose(StreamSocket* user)
 391         {
 392                 CloseSession(&sessions[user->GetFd()]);
 393         }
 394
 395         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 396         {
 397                 issl_session* session = &sessions[user->GetFd()];
 398
 399                 if (!session->sess)
 400                 {
 401                         CloseSession(session);
 402                         user->SetError("No SSL session");
 403                         return -1;
 404                 }
 405
 406                 if (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE)
 407                 {
 408                         // The handshake isn't finished, try to finish it.
 409
 410                         if(!Handshake(session, user))
 411                         {
 412                                 if (session->status != ISSL_CLOSING)
 413                                         return 0;
 414                                 return -1;
 415                         }
 416                 }
 417
 418                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 419
 420                 if (session->status == ISSL_HANDSHAKEN)
 421                 {
 422                         char* buffer = ServerInstance->GetReadBuffer();
 423                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 424                         int ret = gnutls_record_recv(session->sess, buffer, bufsiz);
 425                         if (ret > 0)
 426                         {
 427                                 recvq.append(buffer, ret);
 428                                 return 1;
 429                         }
 430                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 431                         {
 432                                 return 0;
 433                         }
 434                         else if (ret == 0)
 435                         {
 436                                 user->SetError("SSL Connection closed");
 437                                 CloseSession(session);
 438                                 return -1;
 439                         }
 440                         else
 441                         {
 442                                 user->SetError(gnutls_strerror(ret));
 443                                 CloseSession(session);
 444                                 return -1;
 445                         }
 446                 }
 447                 else if (session->status == ISSL_CLOSING)
 448                         return -1;
 449
 450                 return 0;
 451         }
 452
 453         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 454         {
 455                 issl_session* session = &sessions[user->GetFd()];
 456
 457                 if (!session->sess)
 458                 {
 459                         CloseSession(session);
 460                         user->SetError("No SSL session");
 461                         return -1;
 462                 }
 463
 464                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 465                 {
 466                         // The handshake isn't finished, try to finish it.
 467                         Handshake(session, user);
 468                         if (session->status != ISSL_CLOSING)
 469                                 return 0;
 470                         return -1;
 471                 }
 472
 473                 int ret = 0;
 474
 475                 if (session->status == ISSL_HANDSHAKEN)
 476                 {
 477                         ret = gnutls_record_send(session->sess, sendq.data(), sendq.length());
 478
 479                         if (ret == (int)sendq.length())
 480                         {
 481                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE);
 482                                 return 1;
 483                         }
 484                         else if (ret > 0)
 485                         {
 486                                 sendq = sendq.substr(ret);
 487                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 488                                 return 0;
 489                         }
 490                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 491                         {
 492                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 493                                 return 0;
 494                         }
 495                         else if (ret == 0)
 496                         {
 497                                 CloseSession(session);
 498                                 user->SetError("SSL Connection closed");
 499                                 return -1;
 500                         }
 501                         else // (ret < 0)
 502                         {
 503                                 user->SetError(gnutls_strerror(ret));
 504                                 CloseSession(session);
 505                                 return -1;
 506                         }
 507                 }
 508
 509                 return 0;
 510         }
 511
 512         bool Handshake(issl_session* session, StreamSocket* user)
 513         {
 514                 int ret = gnutls_handshake(session->sess);
 515
 516                 if (ret < 0)
 517                 {
 518                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 519                         {
 520                                 // Handshake needs resuming later, read() or write() would have blocked.
 521
 522                                 if(gnutls_record_get_direction(session->sess) == 0)
 523                                 {
 524                                         // gnutls_handshake() wants to read() again.
 525                                         session->status = ISSL_HANDSHAKING_READ;
 526                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 527                                 }
 528                                 else
 529                                 {
 530                                         // gnutls_handshake() wants to write() again.
 531                                         session->status = ISSL_HANDSHAKING_WRITE;
 532                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 533                                 }
 534                         }
 535                         else
 536                         {
 537                                 user->SetError(std::string("Handshake Failed - ") + gnutls_strerror(ret));
 538                                 CloseSession(session);
 539                                 session->status = ISSL_CLOSING;
 540                         }
 541
 542                         return false;
 543                 }
 544                 else
 545                 {
 546                         // Change the seesion state
 547                         session->status = ISSL_HANDSHAKEN;
 548
 549                         VerifyCertificate(session,user);
 550
 551                         // Finish writing, if any left
 552                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 553
 554                         return true;
 555                 }
 556         }
 557
 558         void OnUserConnect(LocalUser* user)
 559         {
 560                 if (user->eh.GetIOHook() == this)
 561                 {
 562                         if (sessions[user->GetFd()].sess)
 563                         {
 564                                 ssl_cert* cert = sessions[user->GetFd()].cert;
 565                                 SSLCertSubmission(user, this, ServerInstance->Modules->Find("m_sslinfo.so"), cert);
 566                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 567                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 568                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 569                                 if (cert->fingerprint.empty())
 570                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 571                                 else
 572                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\""
 573                                                 " and your SSL fingerprint is %s", user->nick.c_str(), cipher.c_str(), cert->fingerprint.c_str());
 574                         }
 575                 }
 576         }
 577
 578         void CloseSession(issl_session* session)
 579         {
 580                 if (session->sess)
 581                 {
 582                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 583                         gnutls_deinit(session->sess);
 584                 }
 585                 session->sess = NULL;
 586                 session->cert = NULL;
 587                 session->status = ISSL_NONE;
 588         }
 589
 590         void VerifyCertificate(issl_session* session, StreamSocket* user)
 591         {
 592                 if (!session->sess || !user || session->cert)
 593                         return;
 594
 595                 unsigned int status;
 596                 const gnutls_datum_t* cert_list;
 597                 int ret;
 598                 unsigned int cert_list_size;
 599                 gnutls_x509_crt_t cert;
 600                 char name[MAXBUF];
 601                 unsigned char digest[MAXBUF];
 602                 size_t digest_size = sizeof(digest);
 603                 size_t name_size = sizeof(name);
 604                 ssl_cert* certinfo = new ssl_cert;
 605                 session->cert = certinfo;
 606
 607                 /* This verification function uses the trusted CAs in the credentials
 608                  * structure. So you must have installed one or more CA certificates.
 609                  */
 610                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 611
 612                 if (ret < 0)
 613                 {
 614                         certinfo->error = std::string(gnutls_strerror(ret));
 615                         return;
 616                 }
 617
 618                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 619                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 620                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 621                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 622
 623                 /* Up to here the process is the same for X.509 certificates and
 624                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 625                  * be easily extended to work with openpgp keys as well.
 626                  */
 627                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 628                 {
 629                         certinfo->error = "No X509 keys sent";
 630                         return;
 631                 }
 632
 633                 ret = gnutls_x509_crt_init(&cert);
 634                 if (ret < 0)
 635                 {
 636                         certinfo->error = gnutls_strerror(ret);
 637                         return;
 638                 }
 639
 640                 cert_list_size = 0;
 641                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 642                 if (cert_list == NULL)
 643                 {
 644                         certinfo->error = "No certificate was found";
 645                         goto info_done_dealloc;
 646                 }
 647
 648                 /* This is not a real world example, since we only check the first
 649                  * certificate in the given chain.
 650                  */
 651
 652                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 653                 if (ret < 0)
 654                 {
 655                         certinfo->error = gnutls_strerror(ret);
 656                         goto info_done_dealloc;
 657                 }
 658
 659                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 660                 certinfo->dn = name;
 661
 662                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 663                 certinfo->issuer = name;
 664
 665                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, hash, digest, &digest_size)) < 0)
 666                 {
 667                         certinfo->error = gnutls_strerror(ret);
 668                 }
 669                 else
 670                 {
 671                         certinfo->fingerprint = irc::hex(digest, digest_size);
 672                 }
 673
 674                 /* Beware here we do not check for errors.
 675                  */
 676                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 677                 {
 678                         certinfo->error = "Not activated, or expired certificate";
 679                 }
 680
 681 info_done_dealloc:
 682                 gnutls_x509_crt_deinit(cert);
 683         }
 684
 685         void OnEvent(Event& ev)
 686         {
 687                 capHandler.HandleEvent(ev);
 688         }
 689 };
 690
 691 MODULE_INIT(ModuleSSLGnuTLS)