src/modules/extra/m_ssl_gnutls.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *          the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include <gnutls/gnutls.h>
  16 #include <gnutls/x509.h>
  17 #include "transport.h"
  18 #include "m_cap.h"
  19
  20 #ifdef WINDOWS
  21 #pragma comment(lib, "libgnutls-13.lib")
  22 #endif
  23
  24 /* $ModDesc: Provides SSL support for clients */
  25 /* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") */
  26 /* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") */
  27 /* $ModDep: transport.h */
  28 /* $CopyInstall: conf/key.pem $(CONPATH) */
  29 /* $CopyInstall: conf/cert.pem $(CONPATH) */
  30
  31 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  32
  33 static gnutls_x509_crt_t x509_cert;
  34 static gnutls_x509_privkey_t x509_key;
  35 static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs,
  36         const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr_st * st) {
  37
  38         st->type = GNUTLS_CRT_X509;
  39         st->ncerts = 1;
  40         st->cert.x509 = &x509_cert;
  41         st->key.x509 = x509_key;
  42         st->deinit_all = 0;
  43
  44         return 0;
  45 }
  46
  47 static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t user_wrap, void* buffer, size_t size)
  48 {
  49         StreamSocket* user = reinterpret_cast<StreamSocket*>(user_wrap);
  50         if (user->GetEventMask() & FD_READ_WILL_BLOCK)
  51         {
  52                 errno = EAGAIN;
  53                 return -1;
  54         }
  55         int rv = recv(user->GetFd(), buffer, size, 0);
  56         if (rv < (int)size)
  57                 ServerInstance->SE->ChangeEventMask(user, FD_READ_WILL_BLOCK);
  58         return rv;
  59 }
  60
  61 static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t user_wrap, const void* buffer, size_t size)
  62 {
  63         StreamSocket* user = reinterpret_cast<StreamSocket*>(user_wrap);
  64         if (user->GetEventMask() & FD_WRITE_WILL_BLOCK)
  65         {
  66                 errno = EAGAIN;
  67                 return -1;
  68         }
  69         int rv = send(user->GetFd(), buffer, size, 0);
  70         if (rv < (int)size)
  71                 ServerInstance->SE->ChangeEventMask(user, FD_WRITE_WILL_BLOCK);
  72         return rv;
  73 }
  74
  75 /** Represents an SSL user's extra data
  76  */
  77 class issl_session : public classbase
  78 {
  79 public:
  80         issl_session()
  81         {
  82                 sess = NULL;
  83         }
  84
  85         gnutls_session_t sess;
  86         issl_status status;
  87 };
  88
  89 class CommandStartTLS : public Command
  90 {
  91  public:
  92         CommandStartTLS (Module* mod) : Command(mod, "STARTTLS")
  93         {
  94                 works_before_reg = true;
  95         }
  96
  97         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  98         {
  99                 /* changed from == REG_ALL to catch clients sending STARTTLS
 100                  * after NICK and USER but before OnUserConnect completes and
 101                  * give a proper error message (see bug #645) - dz
 102                  */
 103                 if (user->registered != REG_NONE)
 104                 {
 105                         user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration has started", user->nick.c_str());
 106                 }
 107                 else
 108                 {
 109                         if (!user->GetIOHook())
 110                         {
 111                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
 112                                 user->AddIOHook(creator);
 113                                 creator->OnStreamSocketAccept(user, NULL, NULL);
 114                         }
 115                         else
 116                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
 117                 }
 118
 119                 return CMD_FAILURE;
 120         }
 121 };
 122
 123 class ModuleSSLGnuTLS : public Module
 124 {
 125         std::set<ListenSocketBase*> listenports;
 126
 127         issl_session* sessions;
 128
 129         gnutls_certificate_credentials x509_cred;
 130         gnutls_dh_params dh_params;
 131
 132         std::string keyfile;
 133         std::string certfile;
 134         std::string cafile;
 135         std::string crlfile;
 136         std::string sslports;
 137         int dh_bits;
 138
 139         bool cred_alloc;
 140
 141         CommandStartTLS starttls;
 142
 143         GenericCap capHandler;
 144  public:
 145
 146         ModuleSSLGnuTLS(InspIRCd* Me)
 147                 : Module(Me), starttls(this), capHandler(this, "tls")
 148         {
 149                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 150
 151                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 152
 153                 gnutls_global_init(); // This must be called once in the program
 154                 gnutls_x509_crt_init(&x509_cert);
 155                 gnutls_x509_privkey_init(&x509_key);
 156
 157                 cred_alloc = false;
 158                 // Needs the flag as it ignores a plain /rehash
 159                 OnModuleRehash(NULL,"ssl");
 160
 161                 // Void return, guess we assume success
 162                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 163                 Implementation eventlist[] = { I_On005Numeric, I_OnRequest, I_OnRehash, I_OnModuleRehash, I_OnPostConnect,
 164                         I_OnEvent, I_OnHookIO };
 165                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 166
 167                 ServerInstance->AddCommand(&starttls);
 168         }
 169
 170         void OnRehash(User* user)
 171         {
 172                 ConfigReader Conf(ServerInstance);
 173
 174                 listenports.clear();
 175                 sslports.clear();
 176
 177                 for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 178                 {
 179                         ListenSocketBase* port = ServerInstance->ports[i];
 180                         std::string desc = port->GetDescription();
 181                         if (desc != "gnutls")
 182                                 continue;
 183
 184                         listenports.insert(port);
 185                         std::string portid = port->GetBindDesc();
 186
 187                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str());
 188                         if (port->GetIP() != "127.0.0.1")
 189                                 sslports.append(portid).append(";");
 190                 }
 191
 192                 if (!sslports.empty())
 193                         sslports.erase(sslports.end() - 1);
 194         }
 195
 196         void OnModuleRehash(User* user, const std::string &param)
 197         {
 198                 if(param != "ssl")
 199                         return;
 200
 201                 OnRehash(user);
 202
 203                 ConfigReader Conf(ServerInstance);
 204
 205                 std::string confdir(ServerInstance->ConfigFileName);
 206                 // +1 so we the path ends with a /
 207                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 208
 209                 cafile = Conf.ReadValue("gnutls", "cafile", 0);
 210                 crlfile = Conf.ReadValue("gnutls", "crlfile", 0);
 211                 certfile = Conf.ReadValue("gnutls", "certfile", 0);
 212                 keyfile = Conf.ReadValue("gnutls", "keyfile", 0);
 213                 dh_bits = Conf.ReadInteger("gnutls", "dhbits", 0, false);
 214
 215                 // Set all the default values needed.
 216                 if (cafile.empty())
 217                         cafile = "ca.pem";
 218
 219                 if (crlfile.empty())
 220                         crlfile = "crl.pem";
 221
 222                 if (certfile.empty())
 223                         certfile = "cert.pem";
 224
 225                 if (keyfile.empty())
 226                         keyfile = "key.pem";
 227
 228                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 229                         dh_bits = 1024;
 230
 231                 // Prepend relative paths with the path to the config directory.
 232                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 233                         cafile = confdir + cafile;
 234
 235                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 236                         crlfile = confdir + crlfile;
 237
 238                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 239                         certfile = confdir + certfile;
 240
 241                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 242                         keyfile = confdir + keyfile;
 243
 244                 int ret;
 245
 246                 if (cred_alloc)
 247                 {
 248                         // Deallocate the old credentials
 249                         gnutls_dh_params_deinit(dh_params);
 250                         gnutls_certificate_free_credentials(x509_cred);
 251                 }
 252                 else
 253                         cred_alloc = true;
 254
 255                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 256                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 257
 258                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 259                         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));
 260
 261                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 262                         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));
 263
 264                 FileReader reader(ServerInstance);
 265
 266                 reader.LoadFile(certfile);
 267                 std::string cert_string = reader.Contents();
 268                 gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), cert_string.length() };
 269
 270                 reader.LoadFile(keyfile);
 271                 std::string key_string = reader.Contents();
 272                 gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), key_string.length() };
 273
 274                 // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 275                 if((ret = gnutls_x509_crt_import(x509_cert, &cert_datum, GNUTLS_X509_FMT_PEM)) < 0)
 276                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + std::string(gnutls_strerror(ret)));
 277
 278                 if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0)
 279                         throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret)));
 280
 281                 if((ret = gnutls_certificate_set_x509_key(x509_cred, &x509_cert, 1, x509_key)) < 0)
 282                         throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
 283
 284                 gnutls_certificate_client_set_retrieve_function (x509_cred, cert_callback);
 285
 286                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 287                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 288
 289                 // This may be on a large (once a day or week) timer eventually.
 290                 GenerateDHParams();
 291         }
 292
 293         void GenerateDHParams()
 294         {
 295                 // Generate Diffie Hellman parameters - for use with DHE
 296                 // kx algorithms. These should be discarded and regenerated
 297                 // once a day, once a week or once a month. Depending on the
 298                 // security requirements.
 299
 300                 int ret;
 301
 302                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 303                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 304         }
 305
 306         ~ModuleSSLGnuTLS()
 307         {
 308                 gnutls_x509_crt_deinit(x509_cert);
 309                 gnutls_x509_privkey_deinit(x509_key);
 310                 gnutls_dh_params_deinit(dh_params);
 311                 gnutls_certificate_free_credentials(x509_cred);
 312                 gnutls_global_deinit();
 313                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 314                 delete[] sessions;
 315         }
 316
 317         void OnCleanup(int target_type, void* item)
 318         {
 319                 if(target_type == TYPE_USER)
 320                 {
 321                         User* user = static_cast<User*>(item);
 322
 323                         if (user->GetIOHook() == this)
 324                         {
 325                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 326                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 327                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 328                                 user->DelIOHook();
 329                         }
 330                 }
 331         }
 332
 333         Version GetVersion()
 334         {
 335                 return Version("Provides SSL support for clients", VF_VENDOR, API_VERSION);
 336         }
 337
 338
 339         void On005Numeric(std::string &output)
 340         {
 341                 if (!sslports.empty())
 342                         output.append(" SSL=" + sslports);
 343                 output.append(" STARTTLS");
 344         }
 345
 346         void OnHookIO(StreamSocket* user, ListenSocketBase* lsb)
 347         {
 348                 if (!user->GetIOHook() && listenports.find(lsb) != listenports.end())
 349                 {
 350                         /* Hook the user with our module */
 351                         user->AddIOHook(this);
 352                 }
 353         }
 354
 355         const char* OnRequest(Request* request)
 356         {
 357                 ISHRequest* ISR = static_cast<ISHRequest*>(request);
 358                 if (strcmp("IS_NAME", request->GetId()) == 0)
 359                 {
 360                         return "gnutls";
 361                 }
 362                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 363                 {
 364                         ISR->Sock->AddIOHook(this);
 365                         return "OK";
 366                 }
 367                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 368                 {
 369                         ISR->Sock->DelIOHook();
 370                         return "OK";
 371                 }
 372                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 373                 {
 374                         if (ISR->Sock->GetFd() < 0)
 375                                 return "OK";
 376
 377                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 378                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 379                 }
 380                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 381                 {
 382                         if (ISR->Sock->GetFd() > -1)
 383                         {
 384                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 385                                 if (session->sess)
 386                                 {
 387                                         if (static_cast<Extensible*>(ServerInstance->SE->GetRef(ISR->Sock->GetFd())) == static_cast<Extensible*>(ISR->Sock))
 388                                         {
 389                                                 return "OK";
 390                                         }
 391                                 }
 392                         }
 393                 }
 394                 else if (strcmp("GET_CERT", request->GetId()) == 0)
 395                 {
 396                         Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so");
 397                         if (sslinfo)
 398                                 return sslinfo->OnRequest(request);
 399                 }
 400                 return NULL;
 401         }
 402
 403
 404         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 405         {
 406                 int fd = user->GetFd();
 407                 issl_session* session = &sessions[fd];
 408
 409                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 410                 if (session->sess)
 411                         return;
 412
 413                 gnutls_init(&session->sess, GNUTLS_SERVER);
 414
 415                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 416                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 417                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 418
 419                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
 420                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 421                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 422
 423                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 424
 425                 Handshake(session, user);
 426         }
 427
 428         void OnStreamSocketConnect(StreamSocket* user)
 429         {
 430                 issl_session* session = &sessions[user->GetFd()];
 431
 432                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 433
 434                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 435                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 436                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 437                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
 438                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 439                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 440
 441                 Handshake(session, user);
 442         }
 443
 444         void OnStreamSocketClose(StreamSocket* user)
 445         {
 446                 CloseSession(&sessions[user->GetFd()]);
 447         }
 448
 449         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 450         {
 451                 issl_session* session = &sessions[user->GetFd()];
 452
 453                 if (!session->sess)
 454                 {
 455                         CloseSession(session);
 456                         user->SetError("No SSL session");
 457                         return -1;
 458                 }
 459
 460                 if (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE)
 461                 {
 462                         // The handshake isn't finished, try to finish it.
 463
 464                         if(!Handshake(session, user))
 465                         {
 466                                 if (session->status != ISSL_CLOSING)
 467                                         return 0;
 468                                 user->SetError("Handshake Failed");
 469                                 return -1;
 470                         }
 471                 }
 472
 473                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 474
 475                 if (session->status == ISSL_HANDSHAKEN)
 476                 {
 477                         char* buffer = ServerInstance->GetReadBuffer();
 478                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 479                         int ret = gnutls_record_recv(session->sess, buffer, bufsiz);
 480                         if (ret > 0)
 481                         {
 482                                 recvq.append(buffer, ret);
 483                                 return 1;
 484                         }
 485                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 486                         {
 487                                 return 0;
 488                         }
 489                         else if (ret == 0)
 490                         {
 491                                 user->SetError("SSL Connection closed");
 492                                 CloseSession(session);
 493                                 return -1;
 494                         }
 495                         else
 496                         {
 497                                 user->SetError(gnutls_strerror(ret));
 498                                 CloseSession(session);
 499                                 return -1;
 500                         }
 501                 }
 502                 else if (session->status == ISSL_CLOSING)
 503                         return -1;
 504
 505                 return 0;
 506         }
 507
 508         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 509         {
 510                 issl_session* session = &sessions[user->GetFd()];
 511
 512                 if (!session->sess)
 513                 {
 514                         CloseSession(session);
 515                         user->SetError("No SSL session");
 516                         return -1;
 517                 }
 518
 519                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 520                 {
 521                         // The handshake isn't finished, try to finish it.
 522                         Handshake(session, user);
 523                         if (session->status != ISSL_CLOSING)
 524                                 return 0;
 525                         user->SetError("Handshake Failed");
 526                         return -1;
 527                 }
 528
 529                 int ret = 0;
 530
 531                 if (session->status == ISSL_HANDSHAKEN)
 532                 {
 533                         ret = gnutls_record_send(session->sess, sendq.data(), sendq.length());
 534
 535                         if (ret == (int)sendq.length())
 536                         {
 537                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE);
 538                                 return 1;
 539                         }
 540                         else if (ret > 0)
 541                         {
 542                                 sendq = sendq.substr(ret);
 543                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 544                                 return 0;
 545                         }
 546                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 547                         {
 548                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 549                                 return 0;
 550                         }
 551                         else if (ret == 0)
 552                         {
 553                                 CloseSession(session);
 554                                 user->SetError("SSL Connection closed");
 555                                 return -1;
 556                         }
 557                         else // (ret < 0)
 558                         {
 559                                 user->SetError(gnutls_strerror(ret));
 560                                 CloseSession(session);
 561                                 return -1;
 562                         }
 563                 }
 564
 565                 return 0;
 566         }
 567
 568         bool Handshake(issl_session* session, StreamSocket* user)
 569         {
 570                 int ret = gnutls_handshake(session->sess);
 571
 572                 if (ret < 0)
 573                 {
 574                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 575                         {
 576                                 // Handshake needs resuming later, read() or write() would have blocked.
 577
 578                                 if(gnutls_record_get_direction(session->sess) == 0)
 579                                 {
 580                                         // gnutls_handshake() wants to read() again.
 581                                         session->status = ISSL_HANDSHAKING_READ;
 582                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 583                                 }
 584                                 else
 585                                 {
 586                                         // gnutls_handshake() wants to write() again.
 587                                         session->status = ISSL_HANDSHAKING_WRITE;
 588                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 589                                 }
 590                         }
 591                         else
 592                         {
 593                                 CloseSession(session);
 594                                 session->status = ISSL_CLOSING;
 595                         }
 596
 597                         return false;
 598                 }
 599                 else
 600                 {
 601                         // Change the seesion state
 602                         session->status = ISSL_HANDSHAKEN;
 603
 604                         VerifyCertificate(session,user);
 605
 606                         // Finish writing, if any left
 607                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 608
 609                         return true;
 610                 }
 611         }
 612
 613         void OnPostConnect(User* user)
 614         {
 615                 // This occurs AFTER OnUserConnect so we can be sure the
 616                 // protocol module has propagated the NICK message.
 617                 if (user->GetIOHook() == this && (IS_LOCAL(user)))
 618                 {
 619                         if (sessions[user->GetFd()].sess)
 620                         {
 621                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 622                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 623                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 624                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 625                         }
 626                 }
 627         }
 628
 629         void CloseSession(issl_session* session)
 630         {
 631                 if(session->sess)
 632                 {
 633                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 634                         gnutls_deinit(session->sess);
 635                 }
 636
 637                 session->sess = NULL;
 638                 session->status = ISSL_NONE;
 639         }
 640
 641         void VerifyCertificate(issl_session* session, Extensible* user)
 642         {
 643                 if (!session->sess || !user)
 644                         return;
 645
 646                 Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so");
 647                 if (!sslinfo)
 648                         return;
 649
 650                 unsigned int status;
 651                 const gnutls_datum_t* cert_list;
 652                 int ret;
 653                 unsigned int cert_list_size;
 654                 gnutls_x509_crt_t cert;
 655                 char name[MAXBUF];
 656                 unsigned char digest[MAXBUF];
 657                 size_t digest_size = sizeof(digest);
 658                 size_t name_size = sizeof(name);
 659                 ssl_cert* certinfo = new ssl_cert;
 660
 661                 /* This verification function uses the trusted CAs in the credentials
 662                  * structure. So you must have installed one or more CA certificates.
 663                  */
 664                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 665
 666                 if (ret < 0)
 667                 {
 668                         certinfo->error = std::string(gnutls_strerror(ret));
 669                         goto info_done;
 670                 }
 671
 672                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 673                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 674                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 675                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 676
 677                 /* Up to here the process is the same for X.509 certificates and
 678                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 679                  * be easily extended to work with openpgp keys as well.
 680                  */
 681                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 682                 {
 683                         certinfo->error = "No X509 keys sent";
 684                         goto info_done;
 685                 }
 686
 687                 ret = gnutls_x509_crt_init(&cert);
 688                 if (ret < 0)
 689                 {
 690                         certinfo->error = gnutls_strerror(ret);
 691                         goto info_done;
 692                 }
 693
 694                 cert_list_size = 0;
 695                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 696                 if (cert_list == NULL)
 697                 {
 698                         certinfo->error = "No certificate was found";
 699                         goto info_done_dealloc;
 700                 }
 701
 702                 /* This is not a real world example, since we only check the first
 703                  * certificate in the given chain.
 704                  */
 705
 706                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 707                 if (ret < 0)
 708                 {
 709                         certinfo->error = gnutls_strerror(ret);
 710                         goto info_done_dealloc;
 711                 }
 712
 713                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 714                 certinfo->dn = name;
 715
 716                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 717                 certinfo->issuer = name;
 718
 719                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 720                 {
 721                         certinfo->error = gnutls_strerror(ret);
 722                 }
 723                 else
 724                 {
 725                         certinfo->fingerprint = irc::hex(digest, digest_size);
 726                 }
 727
 728                 /* Beware here we do not check for errors.
 729                  */
 730                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 731                 {
 732                         certinfo->error = "Not activated, or expired certificate";
 733                 }
 734
 735 info_done_dealloc:
 736                 gnutls_x509_crt_deinit(cert);
 737 info_done:
 738                 BufferedSocketFingerprintSubmission(user, this, sslinfo, certinfo).Send();
 739         }
 740
 741         void OnEvent(Event* ev)
 742         {
 743                 capHandler.HandleEvent(ev);
 744         }
 745 };
 746
 747 MODULE_INIT(ModuleSSLGnuTLS)