src/modules/extra/m_ssl_gnutls.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/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: exec("libgnutls-config --cflags") */
  26 /* $LinkerFlags: rpath("libgnutls-config --libs") exec("libgnutls-config --libs") */
  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         int inbufoffset;
  58         char* inbuf;
  59         int fd;
  60 };
  61
  62 class CommandStartTLS : public Command
  63 {
  64         Module* Caller;
  65  public:
  66         /* Command 'dalinfo', takes no parameters and needs no special modes */
  67         CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance,"STARTTLS", 0, 0, true), Caller(mod)
  68         {
  69                 this->source = "m_ssl_gnutls.so";
  70         }
  71
  72         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  73         {
  74                 if (user->registered == REG_ALL)
  75                 {
  76                         ServerInstance->Users->QuitUser(user, "STARTTLS not allowed after client registration");
  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(671, "%s :STARTTLS failure", user->nick.c_str());
  88                 }
  89
  90                 return CMD_FAILURE;
  91         }
  92 };
  93
  94 class ModuleSSLGnuTLS : public Module
  95 {
  96
  97         ConfigReader* Conf;
  98
  99         char* dummy;
 100
 101         std::vector<std::string> listenports;
 102
 103         int inbufsize;
 104         issl_session* sessions;
 105
 106         gnutls_certificate_credentials x509_cred;
 107         gnutls_dh_params dh_params;
 108
 109         std::string keyfile;
 110         std::string certfile;
 111         std::string cafile;
 112         std::string crlfile;
 113         std::string sslports;
 114         int dh_bits;
 115
 116         int clientactive;
 117         bool cred_alloc;
 118
 119         CommandStartTLS* starttls;
 120
 121  public:
 122
 123         ModuleSSLGnuTLS(InspIRCd* Me)
 124                 : Module(Me)
 125         {
 126                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 127
 128                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 129
 130                 // Not rehashable...because I cba to reduce all the sizes of existing buffers.
 131                 inbufsize = ServerInstance->Config->NetBufferSize;
 132
 133                 gnutls_global_init(); // This must be called once in the program
 134
 135                 cred_alloc = false;
 136                 // Needs the flag as it ignores a plain /rehash
 137                 OnRehash(NULL,"ssl");
 138
 139                 // Void return, guess we assume success
 140                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 141                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 142                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData, I_OnUnloadModule, I_OnRehash, I_OnWhois, I_OnPostConnect, I_OnEvent, I_OnHookUserIO };
 143                 ServerInstance->Modules->Attach(eventlist, this, 17);
 144
 145                 starttls = new CommandStartTLS(ServerInstance, this);
 146                 ServerInstance->AddCommand(starttls);
 147         }
 148
 149         virtual void OnRehash(User* user, const std::string &param)
 150         {
 151                 Conf = new ConfigReader(ServerInstance);
 152
 153                 listenports.clear();
 154                 clientactive = 0;
 155                 sslports.clear();
 156
 157                 for(int index = 0; index < Conf->Enumerate("bind"); index++)
 158                 {
 159                         // For each <bind> tag
 160                         std::string x = Conf->ReadValue("bind", "type", index);
 161                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", index) == "gnutls"))
 162                         {
 163                                 // Get the port we're meant to be listening on with SSL
 164                                 std::string port = Conf->ReadValue("bind", "port", index);
 165                                 std::string addr = Conf->ReadValue("bind", "address", index);
 166
 167                                 irc::portparser portrange(port, false);
 168                                 long portno = -1;
 169                                 while ((portno = portrange.GetToken()))
 170                                 {
 171                                         clientactive++;
 172                                         try
 173                                         {
 174                                                 listenports.push_back(addr + ":" + ConvToStr(portno));
 175
 176                                                 for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
 177                                                         if ((ServerInstance->Config->ports[i]->GetPort() == portno) && (ServerInstance->Config->ports[i]->GetIP() == addr))
 178                                                                 ServerInstance->Config->ports[i]->SetDescription("ssl");
 179                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %ld", portno);
 180
 181                                                 sslports.append((addr.empty() ? "*" : addr)).append(":").append(ConvToStr(portno)).append(";");
 182                                         }
 183                                         catch (ModuleException &e)
 184                                         {
 185                                                 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());
 186                                         }
 187                                 }
 188                         }
 189                 }
 190
 191                 if (!sslports.empty())
 192                         sslports.erase(sslports.end() - 1);
 193
 194                 if(param != "ssl")
 195                 {
 196                         delete Conf;
 197                         return;
 198                 }
 199
 200                 std::string confdir(ServerInstance->ConfigFileName);
 201                 // +1 so we the path ends with a /
 202                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 203
 204                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 205                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 206                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 207                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 208                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 209
 210                 // Set all the default values needed.
 211                 if (cafile.empty())
 212                         cafile = "ca.pem";
 213
 214                 if (crlfile.empty())
 215                         crlfile = "crl.pem";
 216
 217                 if (certfile.empty())
 218                         certfile = "cert.pem";
 219
 220                 if (keyfile.empty())
 221                         keyfile = "key.pem";
 222
 223                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 224                         dh_bits = 1024;
 225
 226                 // Prepend relative paths with the path to the config directory.
 227                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 228                         cafile = confdir + cafile;
 229
 230                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 231                         crlfile = confdir + crlfile;
 232
 233                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 234                         certfile = confdir + certfile;
 235
 236                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 237                         keyfile = confdir + keyfile;
 238
 239                 int ret;
 240
 241                 if (cred_alloc)
 242                 {
 243                         // Deallocate the old credentials
 244                         gnutls_dh_params_deinit(dh_params);
 245                         gnutls_certificate_free_credentials(x509_cred);
 246                 }
 247                 else
 248                         cred_alloc = true;
 249
 250                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 251                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 252
 253                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 254                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 255
 256                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 257                         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));
 258
 259                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 260                         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));
 261
 262                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 263                 {
 264                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 265                         throw ModuleException("Unable to load GnuTLS server certificate: " + std::string(gnutls_strerror(ret)));
 266                 }
 267
 268                 // This may be on a large (once a day or week) timer eventually.
 269                 GenerateDHParams();
 270
 271                 delete Conf;
 272         }
 273
 274         void GenerateDHParams()
 275         {
 276                 // Generate Diffie Hellman parameters - for use with DHE
 277                 // kx algorithms. These should be discarded and regenerated
 278                 // once a day, once a week or once a month. Depending on the
 279                 // security requirements.
 280
 281                 int ret;
 282
 283                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 284                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 285         }
 286
 287         virtual ~ModuleSSLGnuTLS()
 288         {
 289                 gnutls_dh_params_deinit(dh_params);
 290                 gnutls_certificate_free_credentials(x509_cred);
 291                 gnutls_global_deinit();
 292                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 293                 delete[] sessions;
 294         }
 295
 296         virtual void OnCleanup(int target_type, void* item)
 297         {
 298                 if(target_type == TYPE_USER)
 299                 {
 300                         User* user = (User*)item;
 301
 302                         if (user->GetIOHook() == this)
 303                         {
 304                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 305                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 306                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 307                                 user->DelIOHook();
 308                         }
 309                         if (user->GetExt("ssl_cert", dummy))
 310                         {
 311                                 ssl_cert* tofree;
 312                                 user->GetExt("ssl_cert", tofree);
 313                                 delete tofree;
 314                                 user->Shrink("ssl_cert");
 315                         }
 316                 }
 317         }
 318
 319         virtual void OnUnloadModule(Module* mod, const std::string &name)
 320         {
 321                 if(mod == this)
 322                 {
 323                         for(unsigned int i = 0; i < listenports.size(); i++)
 324                         {
 325                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 326                                         if (listenports[i] == (ServerInstance->Config->ports[j]->GetIP()+":"+ConvToStr(ServerInstance->Config->ports[j]->GetPort())))
 327                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 328                         }
 329                 }
 330         }
 331
 332         virtual Version GetVersion()
 333         {
 334                 return Version("$Id$", VF_VENDOR, API_VERSION);
 335         }
 336
 337
 338         virtual void On005Numeric(std::string &output)
 339         {
 340                 output.append(" SSL=" + sslports);
 341         }
 342
 343         virtual void OnHookUserIO(User* user, const std::string &targetip)
 344         {
 345                 if (!user->GetIOHook() && isin(targetip,user->GetPort(),listenports))
 346                 {
 347                         /* Hook the user with our module */
 348                         user->AddIOHook(this);
 349                 }
 350         }
 351
 352         virtual const char* OnRequest(Request* request)
 353         {
 354                 ISHRequest* ISR = (ISHRequest*)request;
 355                 if (strcmp("IS_NAME", request->GetId()) == 0)
 356                 {
 357                         return "gnutls";
 358                 }
 359                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 360                 {
 361                         const char* ret = "OK";
 362                         try
 363                         {
 364                                 ret = ISR->Sock->AddIOHook((Module*)this) ? "OK" : NULL;
 365                         }
 366                         catch (ModuleException &e)
 367                         {
 368                                 return NULL;
 369                         }
 370                         return ret;
 371                 }
 372                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 373                 {
 374                         return ISR->Sock->DelIOHook() ? "OK" : NULL;
 375                 }
 376                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 377                 {
 378                         if (ISR->Sock->GetFd() < 0)
 379                                 return "OK";
 380
 381                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 382                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 383                 }
 384                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 385                 {
 386                         if (ISR->Sock->GetFd() > -1)
 387                         {
 388                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 389                                 if (session->sess)
 390                                 {
 391                                         if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 392                                         {
 393                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 394                                                 return "OK";
 395                                         }
 396                                 }
 397                         }
 398                 }
 399                 return NULL;
 400         }
 401
 402
 403         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 404         {
 405                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 406                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 407                         return;
 408
 409                 issl_session* session = &sessions[fd];
 410
 411                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 412                 if (session->sess)
 413                         return;
 414
 415                 session->fd = fd;
 416                 session->inbuf = new char[inbufsize];
 417                 session->inbufoffset = 0;
 418
 419                 gnutls_init(&session->sess, GNUTLS_SERVER);
 420
 421                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 422                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 423                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 424
 425                 /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
 426                  * This needs testing, but it's easy enough to rollback if need be
 427                  * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 428                  * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
 429                  *
 430                  * With testing this seems to...not work :/
 431                  */
 432
 433                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 434
 435                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 436
 437                 Handshake(session);
 438         }
 439
 440         virtual void OnRawSocketConnect(int fd)
 441         {
 442                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 443                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 444                         return;
 445
 446                 issl_session* session = &sessions[fd];
 447
 448                 session->fd = fd;
 449                 session->inbuf = new char[inbufsize];
 450                 session->inbufoffset = 0;
 451
 452                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 453
 454                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 455                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 456                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 457                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 458
 459                 Handshake(session);
 460         }
 461
 462         virtual void OnRawSocketClose(int fd)
 463         {
 464                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 465                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 466                         return;
 467
 468                 CloseSession(&sessions[fd]);
 469
 470                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 471
 472                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 473                 {
 474                         ssl_cert* tofree;
 475                         user->GetExt("ssl_cert", tofree);
 476                         delete tofree;
 477                         user->Shrink("ssl_cert");
 478                 }
 479         }
 480
 481         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 482         {
 483                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 484                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 485                         return 0;
 486
 487                 issl_session* session = &sessions[fd];
 488
 489                 if (!session->sess)
 490                 {
 491                         readresult = 0;
 492                         CloseSession(session);
 493                         return 1;
 494                 }
 495
 496                 if (session->status == ISSL_HANDSHAKING_READ)
 497                 {
 498                         // The handshake isn't finished, try to finish it.
 499
 500                         if(!Handshake(session))
 501                         {
 502                                 // Couldn't resume handshake.
 503                                 return -1;
 504                         }
 505                 }
 506                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 507                 {
 508                         errno = EAGAIN;
 509                         MakePollWrite(session);
 510                         return -1;
 511                 }
 512
 513                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 514
 515                 if (session->status == ISSL_HANDSHAKEN)
 516                 {
 517                         // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
 518                         // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
 519                         int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);
 520
 521                         if (ret == 0)
 522                         {
 523                                 // Client closed connection.
 524                                 readresult = 0;
 525                                 CloseSession(session);
 526                                 return 1;
 527                         }
 528                         else if (ret < 0)
 529                         {
 530                                 if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 531                                 {
 532                                         errno = EAGAIN;
 533                                         return -1;
 534                                 }
 535                                 else
 536                                 {
 537                                         readresult = 0;
 538                                         CloseSession(session);
 539                                 }
 540                         }
 541                         else
 542                         {
 543                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 544                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 545                                 // 'buffer' is 'count' long
 546
 547                                 unsigned int length = ret + session->inbufoffset;
 548
 549                                 if(count <= length)
 550                                 {
 551                                         memcpy(buffer, session->inbuf, count);
 552                                         // Move the stuff left in inbuf to the beginning of it
 553                                         memmove(session->inbuf, session->inbuf + count, (length - count));
 554                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 555                                         session->inbufoffset = length - count;
 556                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 557                                         readresult = count;
 558                                 }
 559                                 else
 560                                 {
 561                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 562                                         memcpy(buffer, session->inbuf, length);
 563                                         // Zero the offset, as there's nothing there..
 564                                         session->inbufoffset = 0;
 565                                         // As above
 566                                         readresult = length;
 567                                 }
 568                         }
 569                 }
 570                 else if(session->status == ISSL_CLOSING)
 571                         readresult = 0;
 572
 573                 return 1;
 574         }
 575
 576         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 577         {
 578                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 579                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 580                         return 0;
 581
 582                 issl_session* session = &sessions[fd];
 583                 const char* sendbuffer = buffer;
 584
 585                 if (!session->sess)
 586                 {
 587                         CloseSession(session);
 588                         return 1;
 589                 }
 590
 591                 session->outbuf.append(sendbuffer, count);
 592                 sendbuffer = session->outbuf.c_str();
 593                 count = session->outbuf.size();
 594
 595                 if (session->status == ISSL_HANDSHAKING_WRITE)
 596                 {
 597                         // The handshake isn't finished, try to finish it.
 598                         Handshake(session);
 599                         errno = EAGAIN;
 600                         return -1;
 601                 }
 602
 603                 int ret = 0;
 604
 605                 if (session->status == ISSL_HANDSHAKEN)
 606                 {
 607                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 608
 609                         if (ret == 0)
 610                         {
 611                                 CloseSession(session);
 612                         }
 613                         else if (ret < 0)
 614                         {
 615                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 616                                 {
 617                                         CloseSession(session);
 618                                 }
 619                                 else
 620                                 {
 621                                         errno = EAGAIN;
 622                                 }
 623                         }
 624                         else
 625                         {
 626                                 session->outbuf = session->outbuf.substr(ret);
 627                         }
 628                 }
 629
 630                 MakePollWrite(session);
 631
 632                 /* Who's smart idea was it to return 1 when we havent written anything?
 633                  * This fucks the buffer up in BufferedSocket :p
 634                  */
 635                 return ret < 1 ? 0 : ret;
 636         }
 637
 638         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 639         virtual void OnWhois(User* source, User* dest)
 640         {
 641                 if (!clientactive)
 642                         return;
 643
 644                 // Bugfix, only send this numeric for *our* SSL users
 645                 if (dest->GetExt("ssl", dummy) || ((IS_LOCAL(dest) && (dest->GetIOHook() == this))))
 646                 {
 647                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick.c_str(), dest->nick.c_str());
 648                 }
 649         }
 650
 651         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 652         {
 653                 // check if the linking module wants to know about OUR metadata
 654                 if(extname == "ssl")
 655                 {
 656                         // check if this user has an swhois field to send
 657                         if(user->GetExt(extname, dummy))
 658                         {
 659                                 // call this function in the linking module, let it format the data how it
 660                                 // sees fit, and send it on its way. We dont need or want to know how.
 661                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 662                         }
 663                 }
 664         }
 665
 666         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 667         {
 668                 // check if its our metadata key, and its associated with a user
 669                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 670                 {
 671                         User* dest = (User*)target;
 672                         // if they dont already have an ssl flag, accept the remote server's
 673                         if (!dest->GetExt(extname, dummy))
 674                         {
 675                                 dest->Extend(extname, "ON");
 676                         }
 677                 }
 678         }
 679
 680         bool Handshake(issl_session* session)
 681         {
 682                 int ret = gnutls_handshake(session->sess);
 683
 684                 if (ret < 0)
 685                 {
 686                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 687                         {
 688                                 // Handshake needs resuming later, read() or write() would have blocked.
 689
 690                                 if(gnutls_record_get_direction(session->sess) == 0)
 691                                 {
 692                                         // gnutls_handshake() wants to read() again.
 693                                         session->status = ISSL_HANDSHAKING_READ;
 694                                 }
 695                                 else
 696                                 {
 697                                         // gnutls_handshake() wants to write() again.
 698                                         session->status = ISSL_HANDSHAKING_WRITE;
 699                                         MakePollWrite(session);
 700                                 }
 701                         }
 702                         else
 703                         {
 704                                 // Handshake failed.
 705                                 CloseSession(session);
 706                                 session->status = ISSL_CLOSING;
 707                         }
 708
 709                         return false;
 710                 }
 711                 else
 712                 {
 713                         // Handshake complete.
 714                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 715                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 716                         if (extendme)
 717                         {
 718                                 if (!extendme->GetExt("ssl", dummy))
 719                                         extendme->Extend("ssl", "ON");
 720                         }
 721
 722                         // Change the seesion state
 723                         session->status = ISSL_HANDSHAKEN;
 724
 725                         // Finish writing, if any left
 726                         MakePollWrite(session);
 727
 728                         return true;
 729                 }
 730         }
 731
 732         virtual void OnPostConnect(User* user)
 733         {
 734                 // This occurs AFTER OnUserConnect so we can be sure the
 735                 // protocol module has propagated the NICK message.
 736                 if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
 737                 {
 738                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 739                         ServerInstance->PI->SendMetaData(user, TYPE_USER, "SSL", "on");
 740
 741                         VerifyCertificate(&sessions[user->GetFd()],user);
 742                         if (sessions[user->GetFd()].sess)
 743                         {
 744                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 745                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 746                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 747                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 748                         }
 749                 }
 750         }
 751
 752         void MakePollWrite(issl_session* session)
 753         {
 754                 //OnRawSocketWrite(session->fd, NULL, 0);
 755                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 756                 if (eh)
 757                         ServerInstance->SE->WantWrite(eh);
 758         }
 759
 760         virtual void OnBufferFlushed(User* user)
 761         {
 762                 if (user->GetExt("ssl"))
 763                 {
 764                         issl_session* session = &sessions[user->GetFd()];
 765                         if (session && session->outbuf.size())
 766                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 767                 }
 768         }
 769
 770         void CloseSession(issl_session* session)
 771         {
 772                 if(session->sess)
 773                 {
 774                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 775                         gnutls_deinit(session->sess);
 776                 }
 777
 778                 if(session->inbuf)
 779                 {
 780                         delete[] session->inbuf;
 781                 }
 782
 783                 session->outbuf.clear();
 784                 session->inbuf = NULL;
 785                 session->sess = NULL;
 786                 session->status = ISSL_NONE;
 787         }
 788
 789         void VerifyCertificate(issl_session* session, Extensible* user)
 790         {
 791                 if (!session->sess || !user)
 792                         return;
 793
 794                 unsigned int status;
 795                 const gnutls_datum_t* cert_list;
 796                 int ret;
 797                 unsigned int cert_list_size;
 798                 gnutls_x509_crt_t cert;
 799                 char name[MAXBUF];
 800                 unsigned char digest[MAXBUF];
 801                 size_t digest_size = sizeof(digest);
 802                 size_t name_size = sizeof(name);
 803                 ssl_cert* certinfo = new ssl_cert;
 804
 805                 user->Extend("ssl_cert",certinfo);
 806
 807                 /* This verification function uses the trusted CAs in the credentials
 808                  * structure. So you must have installed one or more CA certificates.
 809                  */
 810                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 811
 812                 if (ret < 0)
 813                 {
 814                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 815                         return;
 816                 }
 817
 818                 if (status & GNUTLS_CERT_INVALID)
 819                 {
 820                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 821                 }
 822                 else
 823                 {
 824                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 825                 }
 826                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 827                 {
 828                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 829                 }
 830                 else
 831                 {
 832                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 833                 }
 834                 if (status & GNUTLS_CERT_REVOKED)
 835                 {
 836                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 837                 }
 838                 else
 839                 {
 840                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 841                 }
 842                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 843                 {
 844                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 845                 }
 846                 else
 847                 {
 848                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 849                 }
 850
 851                 /* Up to here the process is the same for X.509 certificates and
 852                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 853                  * be easily extended to work with openpgp keys as well.
 854                  */
 855                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 856                 {
 857                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 858                         return;
 859                 }
 860
 861                 ret = gnutls_x509_crt_init(&cert);
 862                 if (ret < 0)
 863                 {
 864                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 865                         return;
 866                 }
 867
 868                 cert_list_size = 0;
 869                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 870                 if (cert_list == NULL)
 871                 {
 872                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 873                         return;
 874                 }
 875
 876                 /* This is not a real world example, since we only check the first
 877                  * certificate in the given chain.
 878                  */
 879
 880                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 881                 if (ret < 0)
 882                 {
 883                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 884                         return;
 885                 }
 886
 887                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 888
 889                 certinfo->data.insert(std::make_pair("dn",name));
 890
 891                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 892
 893                 certinfo->data.insert(std::make_pair("issuer",name));
 894
 895                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 896                 {
 897                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 898                 }
 899                 else
 900                 {
 901                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 902                 }
 903
 904                 /* Beware here we do not check for errors.
 905                  */
 906                 if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
 907                 {
 908                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 909                 }
 910
 911                 gnutls_x509_crt_deinit(cert);
 912
 913                 return;
 914         }
 915
 916         void OnEvent(Event* ev)
 917         {
 918                 GenericCapHandler(ev, "tls", "tls");
 919         }
 920
 921         void Prioritize()
 922         {
 923                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 924                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIO_AFTER, &server);
 925         }
 926 };
 927
 928 MODULE_INIT(ModuleSSLGnuTLS)