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