src/modules/extra/m_ssl_gnutls.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2007 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
  16 #include <gnutls/gnutls.h>
  17 #include <gnutls/x509.h>
  18
  19 #include "inspircd_config.h"
  20 #include "configreader.h"
  21 #include "users.h"
  22 #include "channels.h"
  23 #include "modules.h"
  24 #include "socket.h"
  25 #include "hashcomp.h"
  26 #include "transport.h"
  27
  28 #ifdef WINDOWS
  29 #pragma comment(lib, "libgnutls-13.lib")
  30 #undef MAX_DESCRIPTORS
  31 #define MAX_DESCRIPTORS 10000
  32 #endif
  33
  34 /* $ModDesc: Provides SSL support for clients */
  35 /* $CompileFlags: exec("libgnutls-config --cflags") */
  36 /* $LinkerFlags: rpath("libgnutls-config --libs") exec("libgnutls-config --libs") */
  37 /* $ModDep: transport.h */
  38 /* $CopyInstall: conf/key.pem $(CONPATH) */
  39 /* $CopyInstall: conf/cert.pem $(CONPATH) */
  40
  41 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  42
  43 bool isin(int port, const std::vector<int> &portlist)
  44 {
  45         for(unsigned int i = 0; i < portlist.size(); i++)
  46                 if(portlist[i] == port)
  47                         return true;
  48
  49         return false;
  50 }
  51
  52 /** Represents an SSL user's extra data
  53  */
  54 class issl_session : public classbase
  55 {
  56 public:
  57         gnutls_session_t sess;
  58         issl_status status;
  59         std::string outbuf;
  60         int inbufoffset;
  61         char* inbuf;
  62         int fd;
  63 };
  64
  65 class ModuleSSLGnuTLS : public Module
  66 {
  67
  68         ConfigReader* Conf;
  69
  70         char* dummy;
  71
  72         std::vector<int> listenports;
  73
  74         int inbufsize;
  75         issl_session sessions[MAX_DESCRIPTORS];
  76
  77         gnutls_certificate_credentials x509_cred;
  78         gnutls_dh_params dh_params;
  79
  80         std::string keyfile;
  81         std::string certfile;
  82         std::string cafile;
  83         std::string crlfile;
  84         std::string sslports;
  85         int dh_bits;
  86
  87         int clientactive;
  88
  89  public:
  90
  91         ModuleSSLGnuTLS(InspIRCd* Me)
  92                 : Module(Me)
  93         {
  94                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
  95
  96                 // Not rehashable...because I cba to reduce all the sizes of existing buffers.
  97                 inbufsize = ServerInstance->Config->NetBufferSize;
  98
  99                 gnutls_global_init(); // This must be called once in the program
 100
 101                 if(gnutls_certificate_allocate_credentials(&x509_cred) != 0)
 102                         ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials");
 103
 104                 // Guessing return meaning
 105                 if(gnutls_dh_params_init(&dh_params) < 0)
 106                         ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters");
 107
 108                 // Needs the flag as it ignores a plain /rehash
 109                 OnRehash(NULL,"ssl");
 110
 111                 // Void return, guess we assume success
 112                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 113         }
 114
 115         virtual void OnRehash(User* user, const std::string &param)
 116         {
 117                 if(param != "ssl")
 118                         return;
 119
 120                 Conf = new ConfigReader(ServerInstance);
 121
 122                 for(unsigned int i = 0; i < listenports.size(); i++)
 123                 {
 124                         ServerInstance->Config->DelIOHook(listenports[i]);
 125                 }
 126
 127                 listenports.clear();
 128                 clientactive = 0;
 129                 sslports.clear();
 130
 131                 for(int i = 0; i < Conf->Enumerate("bind"); i++)
 132                 {
 133                         // For each <bind> tag
 134                         std::string x = Conf->ReadValue("bind", "type", i);
 135                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", i) == "gnutls"))
 136                         {
 137                                 // Get the port we're meant to be listening on with SSL
 138                                 std::string port = Conf->ReadValue("bind", "port", i);
 139                                 irc::portparser portrange(port, false);
 140                                 long portno = -1;
 141                                 while ((portno = portrange.GetToken()))
 142                                 {
 143                                         clientactive++;
 144                                         try
 145                                         {
 146                                                 if (ServerInstance->Config->AddIOHook(portno, this))
 147                                                 {
 148                                                         listenports.push_back(portno);
 149                                                         for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
 150                                                                 if (ServerInstance->Config->ports[i]->GetPort() == portno)
 151                                                                         ServerInstance->Config->ports[i]->SetDescription("ssl");
 152                                                         ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %d", portno);
 153                                                         sslports.append("*:").append(ConvToStr(portno)).append(";");
 154                                                 }
 155                                                 else
 156                                                 {
 157                                                         ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: FAILED to enable SSL on port %d, maybe you have another ssl or similar module loaded?", portno);
 158                                                 }
 159                                         }
 160                                         catch (ModuleException &e)
 161                                         {
 162                                                 ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: FAILED to enable SSL on port %d: %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());
 163                                         }
 164                                 }
 165                         }
 166                 }
 167
 168                 std::string confdir(ServerInstance->ConfigFileName);
 169                 // +1 so we the path ends with a /
 170                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 171
 172                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 173                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 174                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 175                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 176                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 177
 178                 // Set all the default values needed.
 179                 if (cafile.empty())
 180                         cafile = "ca.pem";
 181
 182                 if (crlfile.empty())
 183                         crlfile = "crl.pem";
 184
 185                 if (certfile.empty())
 186                         certfile = "cert.pem";
 187
 188                 if (keyfile.empty())
 189                         keyfile = "key.pem";
 190
 191                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 192                         dh_bits = 1024;
 193
 194                 // Prepend relative paths with the path to the config directory.
 195                 if(cafile[0] != '/')
 196                         cafile = confdir + cafile;
 197
 198                 if(crlfile[0] != '/')
 199                         crlfile = confdir + crlfile;
 200
 201                 if(certfile[0] != '/')
 202                         certfile = confdir + certfile;
 203
 204                 if(keyfile[0] != '/')
 205                         keyfile = confdir + keyfile;
 206
 207                 int ret;
 208
 209                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 210                         ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));
 211
 212                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 213                         ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));
 214
 215                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 216                 {
 217                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 218                         throw ModuleException("Unable to load GnuTLS server certificate: " + std::string(gnutls_strerror(ret)));
 219                 }
 220
 221                 // This may be on a large (once a day or week) timer eventually.
 222                 GenerateDHParams();
 223
 224                 DELETE(Conf);
 225         }
 226
 227         void GenerateDHParams()
 228         {
 229                 // Generate Diffie Hellman parameters - for use with DHE
 230                 // kx algorithms. These should be discarded and regenerated
 231                 // once a day, once a week or once a month. Depending on the
 232                 // security requirements.
 233
 234                 int ret;
 235
 236                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 237                         ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 238         }
 239
 240         virtual ~ModuleSSLGnuTLS()
 241         {
 242                 gnutls_dh_params_deinit(dh_params);
 243                 gnutls_certificate_free_credentials(x509_cred);
 244                 gnutls_global_deinit();
 245         }
 246
 247         virtual void OnCleanup(int target_type, void* item)
 248         {
 249                 if(target_type == TYPE_USER)
 250                 {
 251                         User* user = (User*)item;
 252
 253                         if(user->GetExt("ssl", dummy) && isin(user->GetPort(), listenports))
 254                         {
 255                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 256                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 257                                 User::QuitUser(ServerInstance, user, "SSL module unloading");
 258                         }
 259                         if (user->GetExt("ssl_cert", dummy) && isin(user->GetPort(), listenports))
 260                         {
 261                                 ssl_cert* tofree;
 262                                 user->GetExt("ssl_cert", tofree);
 263                                 delete tofree;
 264                                 user->Shrink("ssl_cert");
 265                         }
 266                 }
 267         }
 268
 269         virtual void OnUnloadModule(Module* mod, const std::string &name)
 270         {
 271                 if(mod == this)
 272                 {
 273                         for(unsigned int i = 0; i < listenports.size(); i++)
 274                         {
 275                                 ServerInstance->Config->DelIOHook(listenports[i]);
 276                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 277                                         if (ServerInstance->Config->ports[j]->GetPort() == listenports[i])
 278                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 279                         }
 280                 }
 281         }
 282
 283         virtual Version GetVersion()
 284         {
 285                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 286         }
 287
 288         void Implements(char* List)
 289         {
 290                 List[I_On005Numeric] = List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = List[I_OnCleanup] = 1;
 291                 List[I_OnBufferFlushed] = List[I_OnRequest] = List[I_OnSyncUserMetaData] = List[I_OnDecodeMetaData] = List[I_OnUnloadModule] = List[I_OnRehash] = List[I_OnWhois] = List[I_OnPostConnect] = 1;
 292         }
 293
 294         virtual void On005Numeric(std::string &output)
 295         {
 296                 output.append(" SSL=" + sslports);
 297         }
 298
 299         virtual char* OnRequest(Request* request)
 300         {
 301                 ISHRequest* ISR = (ISHRequest*)request;
 302                 if (strcmp("IS_NAME", request->GetId()) == 0)
 303                 {
 304                         return "gnutls";
 305                 }
 306                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 307                 {
 308                         char* ret = "OK";
 309                         try
 310                         {
 311                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (BufferedSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 312                         }
 313                         catch (ModuleException &e)
 314                         {
 315                                 return NULL;
 316                         }
 317                         return ret;
 318                 }
 319                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 320                 {
 321                         return ServerInstance->Config->DelIOHook((BufferedSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 322                 }
 323                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 324                 {
 325                         if (ISR->Sock->GetFd() < 0)
 326                                 return (char*)"OK";
 327
 328                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 329                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : (char*)"OK";
 330                 }
 331                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 332                 {
 333                         if (ISR->Sock->GetFd() > -1)
 334                         {
 335                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 336                                 if (session->sess)
 337                                 {
 338                                         if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 339                                         {
 340                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 341                                                 return "OK";
 342                                         }
 343                                 }
 344                         }
 345                 }
 346                 return NULL;
 347         }
 348
 349
 350         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 351         {
 352                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 353                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 354                         return;
 355
 356                 issl_session* session = &sessions[fd];
 357
 358                 session->fd = fd;
 359                 session->inbuf = new char[inbufsize];
 360                 session->inbufoffset = 0;
 361
 362                 gnutls_init(&session->sess, GNUTLS_SERVER);
 363
 364                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 365                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 366                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 367
 368                 /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
 369                  * This needs testing, but it's easy enough to rollback if need be
 370                  * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 371                  * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
 372                  *
 373                  * With testing this seems to...not work :/
 374                  */
 375
 376                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 377
 378                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 379
 380                 Handshake(session);
 381         }
 382
 383         virtual void OnRawSocketConnect(int fd)
 384         {
 385                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 386                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 387                         return;
 388
 389                 issl_session* session = &sessions[fd];
 390
 391                 session->fd = fd;
 392                 session->inbuf = new char[inbufsize];
 393                 session->inbufoffset = 0;
 394
 395                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 396
 397                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 398                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 399                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 400                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 401
 402                 Handshake(session);
 403         }
 404
 405         virtual void OnRawSocketClose(int fd)
 406         {
 407                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 408                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 409                         return;
 410
 411                 CloseSession(&sessions[fd]);
 412
 413                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 414
 415                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 416                 {
 417                         ssl_cert* tofree;
 418                         user->GetExt("ssl_cert", tofree);
 419                         delete tofree;
 420                         user->Shrink("ssl_cert");
 421                 }
 422         }
 423
 424         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 425         {
 426                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 427                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 428                         return 0;
 429
 430                 issl_session* session = &sessions[fd];
 431
 432                 if (!session->sess)
 433                 {
 434                         readresult = 0;
 435                         CloseSession(session);
 436                         return 1;
 437                 }
 438
 439                 if (session->status == ISSL_HANDSHAKING_READ)
 440                 {
 441                         // The handshake isn't finished, try to finish it.
 442
 443                         if(!Handshake(session))
 444                         {
 445                                 // Couldn't resume handshake.
 446                                 return -1;
 447                         }
 448                 }
 449                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 450                 {
 451                         errno = EAGAIN;
 452                         MakePollWrite(session);
 453                         return -1;
 454                 }
 455
 456                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 457
 458                 if (session->status == ISSL_HANDSHAKEN)
 459                 {
 460                         // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
 461                         // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
 462                         int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);
 463
 464                         if (ret == 0)
 465                         {
 466                                 // Client closed connection.
 467                                 readresult = 0;
 468                                 CloseSession(session);
 469                                 return 1;
 470                         }
 471                         else if (ret < 0)
 472                         {
 473                                 if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 474                                 {
 475                                         errno = EAGAIN;
 476                                         return -1;
 477                                 }
 478                                 else
 479                                 {
 480                                         readresult = 0;
 481                                         CloseSession(session);
 482                                 }
 483                         }
 484                         else
 485                         {
 486                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 487                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 488                                 // 'buffer' is 'count' long
 489
 490                                 unsigned int length = ret + session->inbufoffset;
 491
 492                                 if(count <= length)
 493                                 {
 494                                         memcpy(buffer, session->inbuf, count);
 495                                         // Move the stuff left in inbuf to the beginning of it
 496                                         memcpy(session->inbuf, session->inbuf + count, (length - count));
 497                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 498                                         session->inbufoffset = length - count;
 499                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 500                                         readresult = count;
 501                                 }
 502                                 else
 503                                 {
 504                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 505                                         memcpy(buffer, session->inbuf, length);
 506                                         // Zero the offset, as there's nothing there..
 507                                         session->inbufoffset = 0;
 508                                         // As above
 509                                         readresult = length;
 510                                 }
 511                         }
 512                 }
 513                 else if(session->status == ISSL_CLOSING)
 514                         readresult = 0;
 515
 516                 return 1;
 517         }
 518
 519         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 520         {
 521                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 522                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 523                         return 0;
 524
 525                 issl_session* session = &sessions[fd];
 526                 const char* sendbuffer = buffer;
 527
 528                 if (!session->sess)
 529                 {
 530                         CloseSession(session);
 531                         return 1;
 532                 }
 533
 534                 session->outbuf.append(sendbuffer, count);
 535                 sendbuffer = session->outbuf.c_str();
 536                 count = session->outbuf.size();
 537
 538                 if (session->status == ISSL_HANDSHAKING_WRITE)
 539                 {
 540                         // The handshake isn't finished, try to finish it.
 541                         Handshake(session);
 542                         errno = EAGAIN;
 543                         return -1;
 544                 }
 545
 546                 int ret = 0;
 547
 548                 if (session->status == ISSL_HANDSHAKEN)
 549                 {
 550                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 551
 552                         if (ret == 0)
 553                         {
 554                                 CloseSession(session);
 555                         }
 556                         else if (ret < 0)
 557                         {
 558                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 559                                 {
 560                                         CloseSession(session);
 561                                 }
 562                                 else
 563                                 {
 564                                         errno = EAGAIN;
 565                                 }
 566                         }
 567                         else
 568                         {
 569                                 session->outbuf = session->outbuf.substr(ret);
 570                         }
 571                 }
 572
 573                 MakePollWrite(session);
 574
 575                 /* Who's smart idea was it to return 1 when we havent written anything?
 576                  * This fucks the buffer up in BufferedSocket :p
 577                  */
 578                 return ret < 1 ? 0 : ret;
 579         }
 580
 581         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 582         virtual void OnWhois(User* source, User* dest)
 583         {
 584                 if (!clientactive)
 585                         return;
 586
 587                 // Bugfix, only send this numeric for *our* SSL users
 588                 if(dest->GetExt("ssl", dummy) || (IS_LOCAL(dest) &&  isin(dest->GetPort(), listenports)))
 589                 {
 590                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick, dest->nick);
 591                 }
 592         }
 593
 594         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 595         {
 596                 // check if the linking module wants to know about OUR metadata
 597                 if(extname == "ssl")
 598                 {
 599                         // check if this user has an swhois field to send
 600                         if(user->GetExt(extname, dummy))
 601                         {
 602                                 // call this function in the linking module, let it format the data how it
 603                                 // sees fit, and send it on its way. We dont need or want to know how.
 604                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 605                         }
 606                 }
 607         }
 608
 609         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 610         {
 611                 // check if its our metadata key, and its associated with a user
 612                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 613                 {
 614                         User* dest = (User*)target;
 615                         // if they dont already have an ssl flag, accept the remote server's
 616                         if (!dest->GetExt(extname, dummy))
 617                         {
 618                                 dest->Extend(extname, "ON");
 619                         }
 620                 }
 621         }
 622
 623         bool Handshake(issl_session* session)
 624         {
 625                 int ret = gnutls_handshake(session->sess);
 626
 627                 if (ret < 0)
 628                 {
 629                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 630                         {
 631                                 // Handshake needs resuming later, read() or write() would have blocked.
 632
 633                                 if(gnutls_record_get_direction(session->sess) == 0)
 634                                 {
 635                                         // gnutls_handshake() wants to read() again.
 636                                         session->status = ISSL_HANDSHAKING_READ;
 637                                 }
 638                                 else
 639                                 {
 640                                         // gnutls_handshake() wants to write() again.
 641                                         session->status = ISSL_HANDSHAKING_WRITE;
 642                                         MakePollWrite(session);
 643                                 }
 644                         }
 645                         else
 646                         {
 647                                 // Handshake failed.
 648                                 CloseSession(session);
 649                                 session->status = ISSL_CLOSING;
 650                         }
 651
 652                         return false;
 653                 }
 654                 else
 655                 {
 656                         // Handshake complete.
 657                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 658                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 659                         if (extendme)
 660                         {
 661                                 if (!extendme->GetExt("ssl", dummy))
 662                                         extendme->Extend("ssl", "ON");
 663                         }
 664
 665                         // Change the seesion state
 666                         session->status = ISSL_HANDSHAKEN;
 667
 668                         // Finish writing, if any left
 669                         MakePollWrite(session);
 670
 671                         return true;
 672                 }
 673         }
 674
 675         virtual void OnPostConnect(User* user)
 676         {
 677                 // This occurs AFTER OnUserConnect so we can be sure the
 678                 // protocol module has propagated the NICK message.
 679                 if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
 680                 {
 681                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 682                         std::deque<std::string>* metadata = new std::deque<std::string>;
 683                         metadata->push_back(user->nick);
 684                         metadata->push_back("ssl");             // The metadata id
 685                         metadata->push_back("ON");              // The value to send
 686                         Event* event = new Event((char*)metadata,(Module*)this,"send_metadata");
 687                         event->Send(ServerInstance);            // Trigger the event. We don't care what module picks it up.
 688                         DELETE(event);
 689                         DELETE(metadata);
 690
 691                         VerifyCertificate(&sessions[user->GetFd()],user);
 692                         if (sessions[user->GetFd()].sess)
 693                         {
 694                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 695                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 696                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 697                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick, cipher.c_str());
 698                         }
 699                 }
 700         }
 701
 702         void MakePollWrite(issl_session* session)
 703         {
 704                 //OnRawSocketWrite(session->fd, NULL, 0);
 705                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 706                 if (eh)
 707                         ServerInstance->SE->WantWrite(eh);
 708         }
 709
 710         virtual void OnBufferFlushed(User* user)
 711         {
 712                 if (user->GetExt("ssl"))
 713                 {
 714                         issl_session* session = &sessions[user->GetFd()];
 715                         if (session && session->outbuf.size())
 716                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 717                 }
 718         }
 719
 720         void CloseSession(issl_session* session)
 721         {
 722                 if(session->sess)
 723                 {
 724                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 725                         gnutls_deinit(session->sess);
 726                 }
 727
 728                 if(session->inbuf)
 729                 {
 730                         delete[] session->inbuf;
 731                 }
 732
 733                 session->outbuf.clear();
 734                 session->inbuf = NULL;
 735                 session->sess = NULL;
 736                 session->status = ISSL_NONE;
 737         }
 738
 739         void VerifyCertificate(issl_session* session, Extensible* user)
 740         {
 741                 if (!session->sess || !user)
 742                         return;
 743
 744                 unsigned int status;
 745                 const gnutls_datum_t* cert_list;
 746                 int ret;
 747                 unsigned int cert_list_size;
 748                 gnutls_x509_crt_t cert;
 749                 char name[MAXBUF];
 750                 unsigned char digest[MAXBUF];
 751                 size_t digest_size = sizeof(digest);
 752                 size_t name_size = sizeof(name);
 753                 ssl_cert* certinfo = new ssl_cert;
 754
 755                 user->Extend("ssl_cert",certinfo);
 756
 757                 /* This verification function uses the trusted CAs in the credentials
 758                  * structure. So you must have installed one or more CA certificates.
 759                  */
 760                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 761
 762                 if (ret < 0)
 763                 {
 764                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 765                         return;
 766                 }
 767
 768                 if (status & GNUTLS_CERT_INVALID)
 769                 {
 770                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 771                 }
 772                 else
 773                 {
 774                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 775                 }
 776                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 777                 {
 778                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 779                 }
 780                 else
 781                 {
 782                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 783                 }
 784                 if (status & GNUTLS_CERT_REVOKED)
 785                 {
 786                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 787                 }
 788                 else
 789                 {
 790                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 791                 }
 792                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 793                 {
 794                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 795                 }
 796                 else
 797                 {
 798                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 799                 }
 800
 801                 /* Up to here the process is the same for X.509 certificates and
 802                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 803                  * be easily extended to work with openpgp keys as well.
 804                  */
 805                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 806                 {
 807                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 808                         return;
 809                 }
 810
 811                 ret = gnutls_x509_crt_init(&cert);
 812                 if (ret < 0)
 813                 {
 814                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 815                         return;
 816                 }
 817
 818                 cert_list_size = 0;
 819                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 820                 if (cert_list == NULL)
 821                 {
 822                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 823                         return;
 824                 }
 825
 826                 /* This is not a real world example, since we only check the first
 827                  * certificate in the given chain.
 828                  */
 829
 830                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 831                 if (ret < 0)
 832                 {
 833                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 834                         return;
 835                 }
 836
 837                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 838
 839                 certinfo->data.insert(std::make_pair("dn",name));
 840
 841                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 842
 843                 certinfo->data.insert(std::make_pair("issuer",name));
 844
 845                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 846                 {
 847                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 848                 }
 849                 else
 850                 {
 851                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 852                 }
 853
 854                 /* Beware here we do not check for errors.
 855                  */
 856                 if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
 857                 {
 858                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 859                 }
 860
 861                 gnutls_x509_crt_deinit(cert);
 862
 863                 return;
 864         }
 865
 866 };
 867
 868 MODULE_INIT(ModuleSSLGnuTLS)