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 bool isin(const std::string &host, int port, const std::vector<std::string> &portlist)
  34 {
  35         if (std::find(portlist.begin(), portlist.end(), "*:" + ConvToStr(port)) != portlist.end())
  36                 return true;
  37
  38         if (std::find(portlist.begin(), portlist.end(), ":" + ConvToStr(port)) != portlist.end())
  39                 return true;
  40
  41         return std::find(portlist.begin(), portlist.end(), host + ":" + ConvToStr(port)) != portlist.end();
  42 }
  43
  44 /** Represents an SSL user's extra data
  45  */
  46 class issl_session : public classbase
  47 {
  48 public:
  49         issl_session()
  50         {
  51                 sess = NULL;
  52         }
  53
  54         gnutls_session_t sess;
  55         issl_status status;
  56         std::string outbuf;
  57 };
  58
  59 class CommandStartTLS : public Command
  60 {
  61         Module* Caller;
  62  public:
  63         CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance,"STARTTLS", 0, 0, true), Caller(mod)
  64         {
  65                 this->source = "m_ssl_gnutls.so";
  66         }
  67
  68         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  69         {
  70                 /* changed from == REG_ALL to catch clients sending STARTTLS
  71                  * after NICK and USER but before OnUserConnect completes and
  72                  * give a proper error message (see bug #645) - dz
  73                  */
  74                 if (user->registered != REG_NONE)
  75                 {
  76                         ServerInstance->Users->QuitUser(user, "STARTTLS is not permitted after client registration has started");
  77                 }
  78                 else
  79                 {
  80                         if (!user->GetIOHook())
  81                         {
  82                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
  83                                 user->AddIOHook(Caller);
  84                                 Caller->OnRawSocketAccept(user->GetFd(), user->GetIPString(), user->GetPort());
  85                         }
  86                         else
  87                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
  88                 }
  89
  90                 return CMD_FAILURE;
  91         }
  92 };
  93
  94 class ModuleSSLGnuTLS : public Module
  95 {
  96         std::vector<std::string> listenports;
  97
  98         issl_session* sessions;
  99
 100         gnutls_certificate_credentials x509_cred;
 101         gnutls_dh_params dh_params;
 102
 103         std::string keyfile;
 104         std::string certfile;
 105         std::string cafile;
 106         std::string crlfile;
 107         std::string sslports;
 108         int dh_bits;
 109
 110         int clientactive;
 111         bool cred_alloc;
 112
 113         CommandStartTLS* starttls;
 114
 115  public:
 116
 117         ModuleSSLGnuTLS(InspIRCd* Me)
 118                 : Module(Me)
 119         {
 120                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 121
 122                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 123
 124                 gnutls_global_init(); // This must be called once in the program
 125
 126                 cred_alloc = false;
 127                 // Needs the flag as it ignores a plain /rehash
 128                 OnModuleRehash(NULL,"ssl");
 129
 130                 // Void return, guess we assume success
 131                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 132                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 133                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData,
 134                         I_OnUnloadModule, I_OnRehash, I_OnModuleRehash, I_OnWhois, I_OnPostConnect, I_OnEvent, I_OnHookUserIO };
 135                 ServerInstance->Modules->Attach(eventlist, this, 18);
 136
 137                 starttls = new CommandStartTLS(ServerInstance, this);
 138                 ServerInstance->AddCommand(starttls);
 139         }
 140
 141         virtual void OnRehash(User* user)
 142         {
 143                 ConfigReader Conf(ServerInstance);
 144
 145                 listenports.clear();
 146                 clientactive = 0;
 147                 sslports.clear();
 148
 149                 for(int index = 0; index < Conf.Enumerate("bind"); index++)
 150                 {
 151                         // For each <bind> tag
 152                         std::string x = Conf.ReadValue("bind", "type", index);
 153                         if(((x.empty()) || (x == "clients")) && (Conf.ReadValue("bind", "ssl", index) == "gnutls"))
 154                         {
 155                                 // Get the port we're meant to be listening on with SSL
 156                                 std::string port = Conf.ReadValue("bind", "port", index);
 157                                 std::string addr = Conf.ReadValue("bind", "address", index);
 158
 159                                 if (!addr.empty())
 160                                 {
 161                                         // normalize address, important for IPv6
 162                                         int portint = 0;
 163                                         irc::sockets::sockaddrs bin;
 164                                         if (irc::sockets::aptosa(addr.c_str(), portint, &bin))
 165                                                 irc::sockets::satoap(&bin, addr, portint);
 166                                 }
 167
 168                                 irc::portparser portrange(port, false);
 169                                 long portno = -1;
 170                                 while ((portno = portrange.GetToken()))
 171                                 {
 172                                         clientactive++;
 173                                         try
 174                                         {
 175                                                 listenports.push_back(addr + ":" + ConvToStr(portno));
 176
 177                                                 for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 178                                                         if ((ServerInstance->ports[i]->GetPort() == portno) && (ServerInstance->ports[i]->GetIP() == addr))
 179                                                                 ServerInstance->ports[i]->SetDescription("ssl");
 180                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %ld", portno);
 181
 182                                                 if (addr != "127.0.0.1")
 183                                                         sslports.append((addr.empty() ? "*" : addr)).append(":").append(ConvToStr(portno)).append(";");
 184                                         }
 185                                         catch (ModuleException &e)
 186                                         {
 187                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: FAILED to enable SSL on port %ld: %s. Maybe it's already hooked by the same port on a different IP, or you have an other SSL or similar module loaded?", portno, e.GetReason());
 188                                         }
 189                                 }
 190                         }
 191                 }
 192
 193                 if (!sslports.empty())
 194                         sslports.erase(sslports.end() - 1);
 195         }
 196
 197         virtual void OnModuleRehash(User* user, const std::string &param)
 198         {
 199                 if(param != "ssl")
 200                         return;
 201
 202                 OnRehash(user);
 203
 204                 ConfigReader Conf(ServerInstance);
 205
 206                 std::string confdir(ServerInstance->ConfigFileName);
 207                 // +1 so we the path ends with a /
 208                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 209
 210                 cafile = Conf.ReadValue("gnutls", "cafile", 0);
 211                 crlfile = Conf.ReadValue("gnutls", "crlfile", 0);
 212                 certfile = Conf.ReadValue("gnutls", "certfile", 0);
 213                 keyfile = Conf.ReadValue("gnutls", "keyfile", 0);
 214                 dh_bits = Conf.ReadInteger("gnutls", "dhbits", 0, false);
 215
 216                 // Set all the default values needed.
 217                 if (cafile.empty())
 218                         cafile = "ca.pem";
 219
 220                 if (crlfile.empty())
 221                         crlfile = "crl.pem";
 222
 223                 if (certfile.empty())
 224                         certfile = "cert.pem";
 225
 226                 if (keyfile.empty())
 227                         keyfile = "key.pem";
 228
 229                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 230                         dh_bits = 1024;
 231
 232                 // Prepend relative paths with the path to the config directory.
 233                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 234                         cafile = confdir + cafile;
 235
 236                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 237                         crlfile = confdir + crlfile;
 238
 239                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 240                         certfile = confdir + certfile;
 241
 242                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 243                         keyfile = confdir + keyfile;
 244
 245                 int ret;
 246
 247                 if (cred_alloc)
 248                 {
 249                         // Deallocate the old credentials
 250                         gnutls_dh_params_deinit(dh_params);
 251                         gnutls_certificate_free_credentials(x509_cred);
 252                 }
 253                 else
 254                         cred_alloc = true;
 255
 256                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 257                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 258
 259                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 260                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 261
 262                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 263                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));
 264
 265                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 266                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));
 267
 268                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 269                 {
 270                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 271                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + ", key: " + keyfile + "): " + std::string(gnutls_strerror(ret)));
 272                 }
 273
 274                 // This may be on a large (once a day or week) timer eventually.
 275                 GenerateDHParams();
 276         }
 277
 278         void GenerateDHParams()
 279         {
 280                 // Generate Diffie Hellman parameters - for use with DHE
 281                 // kx algorithms. These should be discarded and regenerated
 282                 // once a day, once a week or once a month. Depending on the
 283                 // security requirements.
 284
 285                 int ret;
 286
 287                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 288                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 289         }
 290
 291         virtual ~ModuleSSLGnuTLS()
 292         {
 293                 gnutls_dh_params_deinit(dh_params);
 294                 gnutls_certificate_free_credentials(x509_cred);
 295                 gnutls_global_deinit();
 296                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 297                 delete[] sessions;
 298         }
 299
 300         virtual void OnCleanup(int target_type, void* item)
 301         {
 302                 if(target_type == TYPE_USER)
 303                 {
 304                         User* user = (User*)item;
 305
 306                         if (user->GetIOHook() == this)
 307                         {
 308                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 309                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 310                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 311                                 user->DelIOHook();
 312                         }
 313                         if (user->GetExt("ssl_cert"))
 314                         {
 315                                 ssl_cert* tofree;
 316                                 user->GetExt("ssl_cert", tofree);
 317                                 delete tofree;
 318                                 user->Shrink("ssl_cert");
 319                         }
 320                 }
 321         }
 322
 323         virtual void OnUnloadModule(Module* mod, const std::string &name)
 324         {
 325                 if(mod == this)
 326                 {
 327                         for(unsigned int i = 0; i < listenports.size(); i++)
 328                         {
 329                                 for (size_t j = 0; j < ServerInstance->ports.size(); j++)
 330                                         if (listenports[i] == (ServerInstance->ports[j]->GetIP()+":"+ConvToStr(ServerInstance->ports[j]->GetPort())))
 331                                                 ServerInstance->ports[j]->SetDescription("plaintext");
 332                         }
 333                 }
 334         }
 335
 336         virtual Version GetVersion()
 337         {
 338                 return Version("$Id$", VF_VENDOR, API_VERSION);
 339         }
 340
 341
 342         virtual void On005Numeric(std::string &output)
 343         {
 344                 if (!sslports.empty())
 345                         output.append(" SSL=" + sslports);
 346                 output.append(" STARTTLS");
 347         }
 348
 349         virtual void OnHookUserIO(User* user, const std::string &targetip)
 350         {
 351                 if (!user->GetIOHook() && isin(targetip,user->GetPort(),listenports))
 352                 {
 353                         /* Hook the user with our module */
 354                         user->AddIOHook(this);
 355                 }
 356         }
 357
 358         virtual const char* OnRequest(Request* request)
 359         {
 360                 ISHRequest* ISR = (ISHRequest*)request;
 361                 if (strcmp("IS_NAME", request->GetId()) == 0)
 362                 {
 363                         return "gnutls";
 364                 }
 365                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 366                 {
 367                         const char* ret = "OK";
 368                         try
 369                         {
 370                                 ret = ISR->Sock->AddIOHook((Module*)this) ? "OK" : NULL;
 371                         }
 372                         catch (ModuleException &e)
 373                         {
 374                                 return NULL;
 375                         }
 376                         return ret;
 377                 }
 378                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 379                 {
 380                         return ISR->Sock->DelIOHook() ? "OK" : NULL;
 381                 }
 382                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 383                 {
 384                         if (ISR->Sock->GetFd() < 0)
 385                                 return "OK";
 386
 387                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 388                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 389                 }
 390                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 391                 {
 392                         if (ISR->Sock->GetFd() > -1)
 393                         {
 394                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 395                                 if (session->sess)
 396                                 {
 397                                         if ((Extensible*)ServerInstance->SE->GetRef(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 398                                         {
 399                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 400                                                 return "OK";
 401                                         }
 402                                 }
 403                         }
 404                 }
 405                 else if (strcmp("GET_FP", request->GetId()) == 0)
 406                 {
 407                         if (ISR->Sock->GetFd() > -1)
 408                         {
 409                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 410                                 if (session->sess)
 411                                 {
 412                                         Extensible* ext = ISR->Sock;
 413                                         ssl_cert* certinfo;
 414                                         if (ext->GetExt("ssl_cert",certinfo))
 415                                                 return certinfo->GetFingerprint().c_str();
 416                                 }
 417                         }
 418                 }
 419                 return NULL;
 420         }
 421
 422
 423         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 424         {
 425                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 426                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 427                         return;
 428
 429                 issl_session* session = &sessions[fd];
 430
 431                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 432                 if (session->sess)
 433                         return;
 434
 435                 gnutls_init(&session->sess, GNUTLS_SERVER);
 436
 437                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 438                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 439                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 440
 441                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 442
 443                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 444
 445                 Handshake(session, fd);
 446         }
 447
 448         virtual void OnRawSocketConnect(int fd)
 449         {
 450                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 451                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 452                         return;
 453
 454                 issl_session* session = &sessions[fd];
 455
 456                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 457
 458                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 459                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 460                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 461                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 462
 463                 Handshake(session, fd);
 464         }
 465
 466         virtual void OnRawSocketClose(int fd)
 467         {
 468                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 469                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 470                         return;
 471
 472                 CloseSession(&sessions[fd]);
 473
 474                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 475
 476                 if ((user) && (user->GetExt("ssl_cert")))
 477                 {
 478                         ssl_cert* tofree;
 479                         user->GetExt("ssl_cert", tofree);
 480                         delete tofree;
 481                         user->Shrink("ssl_cert");
 482                 }
 483         }
 484
 485         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 486         {
 487                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 488                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 489                         return 0;
 490
 491                 issl_session* session = &sessions[fd];
 492
 493                 if (!session->sess)
 494                 {
 495                         readresult = 0;
 496                         CloseSession(session);
 497                         return 1;
 498                 }
 499
 500                 if (session->status == ISSL_HANDSHAKING_READ)
 501                 {
 502                         // The handshake isn't finished, try to finish it.
 503
 504                         if(!Handshake(session, fd))
 505                         {
 506                                 errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 507                                 // Couldn't resume handshake.
 508                                 return -1;
 509                         }
 510                 }
 511                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 512                 {
 513                         errno = EAGAIN;
 514                         MakePollWrite(fd);
 515                         return -1;
 516                 }
 517
 518                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 519
 520                 if (session->status == ISSL_HANDSHAKEN)
 521                 {
 522                         int ret = gnutls_record_recv(session->sess, buffer, count);
 523
 524                         if (ret > 0)
 525                         {
 526                                 readresult = ret;
 527                         }
 528                         else if (ret == 0)
 529                         {
 530                                 // Client closed connection.
 531                                 readresult = 0;
 532                                 CloseSession(session);
 533                                 return 1;
 534                         }
 535                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 536                         {
 537                                 errno = EAGAIN;
 538                                 return -1;
 539                         }
 540                         else
 541                         {
 542                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 543                                                 "m_ssl_gnutls.so: Error while reading on fd %d: %s",
 544                                                 fd, gnutls_strerror(ret));
 545                                 readresult = 0;
 546                                 CloseSession(session);
 547                         }
 548                 }
 549                 else if(session->status == ISSL_CLOSING)
 550                         readresult = 0;
 551
 552                 return 1;
 553         }
 554
 555         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 556         {
 557                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 558                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 559                         return 0;
 560
 561                 issl_session* session = &sessions[fd];
 562                 const char* sendbuffer = buffer;
 563
 564                 if (!session->sess)
 565                 {
 566                         CloseSession(session);
 567                         return 1;
 568                 }
 569
 570                 session->outbuf.append(sendbuffer, count);
 571                 sendbuffer = session->outbuf.c_str();
 572                 count = session->outbuf.size();
 573
 574                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 575                 {
 576                         // The handshake isn't finished, try to finish it.
 577                         Handshake(session, fd);
 578                         errno = session->status == ISSL_CLOSING ? EIO : EAGAIN;
 579                         return -1;
 580                 }
 581
 582                 int ret = 0;
 583
 584                 if (session->status == ISSL_HANDSHAKEN)
 585                 {
 586                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 587
 588                         if (ret == 0)
 589                         {
 590                                 CloseSession(session);
 591                         }
 592                         else if (ret < 0)
 593                         {
 594                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 595                                 {
 596                                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 597                                                         "m_ssl_gnutls.so: Error while writing to fd %d: %s",
 598                                                         fd, gnutls_strerror(ret));
 599                                         CloseSession(session);
 600                                 }
 601                                 else
 602                                 {
 603                                         errno = EAGAIN;
 604                                 }
 605                         }
 606                         else
 607                         {
 608                                 session->outbuf = session->outbuf.substr(ret);
 609                         }
 610                 }
 611
 612                 MakePollWrite(fd);
 613
 614                 /* Who's smart idea was it to return 1 when we havent written anything?
 615                  * This fucks the buffer up in BufferedSocket :p
 616                  */
 617                 return ret < 1 ? 0 : ret;
 618         }
 619
 620         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 621         virtual void OnWhois(User* source, User* dest)
 622         {
 623                 if (!clientactive)
 624                         return;
 625
 626                 // Bugfix, only send this numeric for *our* SSL users
 627                 if (dest->GetExt("ssl"))
 628                 {
 629                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick.c_str(), dest->nick.c_str());
 630                 }
 631         }
 632
 633         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 634         {
 635                 // check if the linking module wants to know about OUR metadata
 636                 if(extname == "ssl")
 637                 {
 638                         // check if this user has an swhois field to send
 639                         if(user->GetExt(extname))
 640                         {
 641                                 // call this function in the linking module, let it format the data how it
 642                                 // sees fit, and send it on its way. We dont need or want to know how.
 643                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 644                         }
 645                 }
 646         }
 647
 648         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 649         {
 650                 // check if its our metadata key, and its associated with a user
 651                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 652                 {
 653                         User* dest = (User*)target;
 654                         // if they dont already have an ssl flag, accept the remote server's
 655                         if (!dest->GetExt(extname))
 656                         {
 657                                 dest->Extend(extname, "ON");
 658                         }
 659                 }
 660         }
 661
 662         bool Handshake(issl_session* session, int fd)
 663         {
 664                 int ret = gnutls_handshake(session->sess);
 665
 666                 if (ret < 0)
 667                 {
 668                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 669                         {
 670                                 // Handshake needs resuming later, read() or write() would have blocked.
 671
 672                                 if(gnutls_record_get_direction(session->sess) == 0)
 673                                 {
 674                                         // gnutls_handshake() wants to read() again.
 675                                         session->status = ISSL_HANDSHAKING_READ;
 676                                 }
 677                                 else
 678                                 {
 679                                         // gnutls_handshake() wants to write() again.
 680                                         session->status = ISSL_HANDSHAKING_WRITE;
 681                                         MakePollWrite(fd);
 682                                 }
 683                         }
 684                         else
 685                         {
 686                                 // Handshake failed.
 687                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 688                                                 "m_ssl_gnutls.so: Handshake failed on fd %d: %s",
 689                                                 fd, gnutls_strerror(ret));
 690                                 CloseSession(session);
 691                                 session->status = ISSL_CLOSING;
 692                         }
 693
 694                         return false;
 695                 }
 696                 else
 697                 {
 698                         // Handshake complete.
 699                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 700                         EventHandler *extendme = ServerInstance->SE->GetRef(fd);
 701                         if (extendme)
 702                         {
 703                                 if (!extendme->GetExt("ssl"))
 704                                         extendme->Extend("ssl", "ON");
 705                         }
 706
 707                         // Change the seesion state
 708                         session->status = ISSL_HANDSHAKEN;
 709
 710                         // Finish writing, if any left
 711                         MakePollWrite(fd);
 712
 713                         return true;
 714                 }
 715         }
 716
 717         virtual void OnPostConnect(User* user)
 718         {
 719                 // This occurs AFTER OnUserConnect so we can be sure the
 720                 // protocol module has propagated the NICK message.
 721                 if (user->GetIOHook() == this && (IS_LOCAL(user)))
 722                 {
 723                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 724                         ServerInstance->PI->SendMetaData(user, TYPE_USER, "ssl", "on");
 725
 726                         VerifyCertificate(&sessions[user->GetFd()],user);
 727                         if (sessions[user->GetFd()].sess)
 728                         {
 729                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 730                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 731                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 732                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 733                         }
 734                 }
 735         }
 736
 737         void MakePollWrite(int fd)
 738         {
 739                 //OnRawSocketWrite(fd, NULL, 0);
 740                 EventHandler* eh = ServerInstance->SE->GetRef(fd);
 741                 if (eh)
 742                         ServerInstance->SE->WantWrite(eh);
 743         }
 744
 745         virtual void OnBufferFlushed(User* user)
 746         {
 747                 if (user->GetIOHook() == this)
 748                 {
 749                         issl_session* session = &sessions[user->GetFd()];
 750                         if (session && session->outbuf.size())
 751                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 752                 }
 753         }
 754
 755         void CloseSession(issl_session* session)
 756         {
 757                 if(session->sess)
 758                 {
 759                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 760                         gnutls_deinit(session->sess);
 761                 }
 762
 763                 session->outbuf.clear();
 764                 session->sess = NULL;
 765                 session->status = ISSL_NONE;
 766         }
 767
 768         void VerifyCertificate(issl_session* session, Extensible* user)
 769         {
 770                 if (!session->sess || !user)
 771                         return;
 772
 773                 unsigned int status;
 774                 const gnutls_datum_t* cert_list;
 775                 int ret;
 776                 unsigned int cert_list_size;
 777                 gnutls_x509_crt_t cert;
 778                 char name[MAXBUF];
 779                 unsigned char digest[MAXBUF];
 780                 size_t digest_size = sizeof(digest);
 781                 size_t name_size = sizeof(name);
 782                 ssl_cert* certinfo = new ssl_cert;
 783
 784                 user->Extend("ssl_cert",certinfo);
 785
 786                 /* This verification function uses the trusted CAs in the credentials
 787                  * structure. So you must have installed one or more CA certificates.
 788                  */
 789                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 790
 791                 if (ret < 0)
 792                 {
 793                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 794                         return;
 795                 }
 796
 797                 if (status & GNUTLS_CERT_INVALID)
 798                 {
 799                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 800                 }
 801                 else
 802                 {
 803                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 804                 }
 805                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 806                 {
 807                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 808                 }
 809                 else
 810                 {
 811                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 812                 }
 813                 if (status & GNUTLS_CERT_REVOKED)
 814                 {
 815                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 816                 }
 817                 else
 818                 {
 819                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 820                 }
 821                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 822                 {
 823                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 824                 }
 825                 else
 826                 {
 827                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 828                 }
 829
 830                 /* Up to here the process is the same for X.509 certificates and
 831                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 832                  * be easily extended to work with openpgp keys as well.
 833                  */
 834                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 835                 {
 836                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 837                         return;
 838                 }
 839
 840                 ret = gnutls_x509_crt_init(&cert);
 841                 if (ret < 0)
 842                 {
 843                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 844                         return;
 845                 }
 846
 847                 cert_list_size = 0;
 848                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 849                 if (cert_list == NULL)
 850                 {
 851                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 852                         return;
 853                 }
 854
 855                 /* This is not a real world example, since we only check the first
 856                  * certificate in the given chain.
 857                  */
 858
 859                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 860                 if (ret < 0)
 861                 {
 862                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 863                         return;
 864                 }
 865
 866                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 867
 868                 certinfo->data.insert(std::make_pair("dn",name));
 869
 870                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 871
 872                 certinfo->data.insert(std::make_pair("issuer",name));
 873
 874                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 875                 {
 876                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 877                 }
 878                 else
 879                 {
 880                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 881                 }
 882
 883                 /* Beware here we do not check for errors.
 884                  */
 885                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 886                 {
 887                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 888                 }
 889
 890                 gnutls_x509_crt_deinit(cert);
 891
 892                 return;
 893         }
 894
 895         void OnEvent(Event* ev)
 896         {
 897                 GenericCapHandler(ev, "tls", "tls");
 898         }
 899
 900         void Prioritize()
 901         {
 902                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 903                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIORITY_AFTER, &server);
 904         }
 905 };
 906
 907 MODULE_INIT(ModuleSSLGnuTLS)