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
  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->Logs->Log("m_ssl_gnutls",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->Logs->Log("m_ssl_gnutls",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                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 114                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData, I_OnUnloadModule, I_OnRehash, I_OnWhois, I_OnPostConnect };
 115                 ServerInstance->Modules->Attach(eventlist, this, 15);
 116         }
 117
 118         virtual void OnRehash(User* user, const std::string &param)
 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 index = 0; index < Conf->Enumerate("bind"); index++)
 132                 {
 133                         // For each <bind> tag
 134                         std::string x = Conf->ReadValue("bind", "type", index);
 135                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", index) == "gnutls"))
 136                         {
 137                                 // Get the port we're meant to be listening on with SSL
 138                                 std::string port = Conf->ReadValue("bind", "port", index);
 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->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %d", portno);
 153                                                         sslports.append("*:").append(ConvToStr(portno)).append(";");
 154                                                 }
 155                                                 else
 156                                                 {
 157                                                         ServerInstance->Logs->Log("m_ssl_gnutls",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->Logs->Log("m_ssl_gnutls",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                 if(param != "ssl")
 169                 {
 170                         delete Conf;
 171                         return;
 172                 }
 173
 174                 std::string confdir(ServerInstance->ConfigFileName);
 175                 // +1 so we the path ends with a /
 176                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 177
 178                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 179                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 180                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 181                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 182                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 183
 184                 // Set all the default values needed.
 185                 if (cafile.empty())
 186                         cafile = "ca.pem";
 187
 188                 if (crlfile.empty())
 189                         crlfile = "crl.pem";
 190
 191                 if (certfile.empty())
 192                         certfile = "cert.pem";
 193
 194                 if (keyfile.empty())
 195                         keyfile = "key.pem";
 196
 197                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 198                         dh_bits = 1024;
 199
 200                 // Prepend relative paths with the path to the config directory.
 201                 if(cafile[0] != '/')
 202                         cafile = confdir + cafile;
 203
 204                 if(crlfile[0] != '/')
 205                         crlfile = confdir + crlfile;
 206
 207                 if(certfile[0] != '/')
 208                         certfile = confdir + certfile;
 209
 210                 if(keyfile[0] != '/')
 211                         keyfile = confdir + keyfile;
 212
 213                 int ret;
 214
 215                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 216                         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));
 217
 218                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 219                         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));
 220
 221                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 222                 {
 223                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 224                         throw ModuleException("Unable to load GnuTLS server certificate: " + std::string(gnutls_strerror(ret)));
 225                 }
 226
 227                 // This may be on a large (once a day or week) timer eventually.
 228                 GenerateDHParams();
 229
 230                 delete Conf;
 231         }
 232
 233         void GenerateDHParams()
 234         {
 235                 // Generate Diffie Hellman parameters - for use with DHE
 236                 // kx algorithms. These should be discarded and regenerated
 237                 // once a day, once a week or once a month. Depending on the
 238                 // security requirements.
 239
 240                 int ret;
 241
 242                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 243                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 244         }
 245
 246         virtual ~ModuleSSLGnuTLS()
 247         {
 248                 gnutls_dh_params_deinit(dh_params);
 249                 gnutls_certificate_free_credentials(x509_cred);
 250                 gnutls_global_deinit();
 251         }
 252
 253         virtual void OnCleanup(int target_type, void* item)
 254         {
 255                 if(target_type == TYPE_USER)
 256                 {
 257                         User* user = (User*)item;
 258
 259                         if(user->GetExt("ssl", dummy) && isin(user->GetPort(), listenports))
 260                         {
 261                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 262                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 263                                 User::QuitUser(ServerInstance, user, "SSL module unloading");
 264                         }
 265                         if (user->GetExt("ssl_cert", dummy) && isin(user->GetPort(), listenports))
 266                         {
 267                                 ssl_cert* tofree;
 268                                 user->GetExt("ssl_cert", tofree);
 269                                 delete tofree;
 270                                 user->Shrink("ssl_cert");
 271                         }
 272                 }
 273         }
 274
 275         virtual void OnUnloadModule(Module* mod, const std::string &name)
 276         {
 277                 if(mod == this)
 278                 {
 279                         for(unsigned int i = 0; i < listenports.size(); i++)
 280                         {
 281                                 ServerInstance->Config->DelIOHook(listenports[i]);
 282                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 283                                         if (ServerInstance->Config->ports[j]->GetPort() == listenports[i])
 284                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 285                         }
 286                 }
 287         }
 288
 289         virtual Version GetVersion()
 290         {
 291                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 292         }
 293
 294
 295         virtual void On005Numeric(std::string &output)
 296         {
 297                 output.append(" SSL=" + sslports);
 298         }
 299
 300         virtual const char* OnRequest(Request* request)
 301         {
 302                 ISHRequest* ISR = (ISHRequest*)request;
 303                 if (strcmp("IS_NAME", request->GetId()) == 0)
 304                 {
 305                         return "gnutls";
 306                 }
 307                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 308                 {
 309                         const char* ret = "OK";
 310                         try
 311                         {
 312                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 313                         }
 314                         catch (ModuleException &e)
 315                         {
 316                                 return NULL;
 317                         }
 318                         return ret;
 319                 }
 320                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 321                 {
 322                         return ServerInstance->Config->DelIOHook((BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 323                 }
 324                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 325                 {
 326                         if (ISR->Sock->GetFd() < 0)
 327                                 return "OK";
 328
 329                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 330                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 331                 }
 332                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 333                 {
 334                         if (ISR->Sock->GetFd() > -1)
 335                         {
 336                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 337                                 if (session->sess)
 338                                 {
 339                                         if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 340                                         {
 341                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 342                                                 return "OK";
 343                                         }
 344                                 }
 345                         }
 346                 }
 347                 return NULL;
 348         }
 349
 350
 351         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 352         {
 353                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 354                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 355                         return;
 356
 357                 issl_session* session = &sessions[fd];
 358
 359                 session->fd = fd;
 360                 session->inbuf = new char[inbufsize];
 361                 session->inbufoffset = 0;
 362
 363                 gnutls_init(&session->sess, GNUTLS_SERVER);
 364
 365                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 366                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 367                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 368
 369                 /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
 370                  * This needs testing, but it's easy enough to rollback if need be
 371                  * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 372                  * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
 373                  *
 374                  * With testing this seems to...not work :/
 375                  */
 376
 377                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 378
 379                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 380
 381                 Handshake(session);
 382         }
 383
 384         virtual void OnRawSocketConnect(int fd)
 385         {
 386                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 387                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 388                         return;
 389
 390                 issl_session* session = &sessions[fd];
 391
 392                 session->fd = fd;
 393                 session->inbuf = new char[inbufsize];
 394                 session->inbufoffset = 0;
 395
 396                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 397
 398                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 399                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 400                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 401                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 402
 403                 Handshake(session);
 404         }
 405
 406         virtual void OnRawSocketClose(int fd)
 407         {
 408                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 409                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 410                         return;
 411
 412                 CloseSession(&sessions[fd]);
 413
 414                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 415
 416                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 417                 {
 418                         ssl_cert* tofree;
 419                         user->GetExt("ssl_cert", tofree);
 420                         delete tofree;
 421                         user->Shrink("ssl_cert");
 422                 }
 423         }
 424
 425         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 426         {
 427                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 428                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 429                         return 0;
 430
 431                 issl_session* session = &sessions[fd];
 432
 433                 if (!session->sess)
 434                 {
 435                         readresult = 0;
 436                         CloseSession(session);
 437                         return 1;
 438                 }
 439
 440                 if (session->status == ISSL_HANDSHAKING_READ)
 441                 {
 442                         // The handshake isn't finished, try to finish it.
 443
 444                         if(!Handshake(session))
 445                         {
 446                                 // Couldn't resume handshake.
 447                                 return -1;
 448                         }
 449                 }
 450                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 451                 {
 452                         errno = EAGAIN;
 453                         MakePollWrite(session);
 454                         return -1;
 455                 }
 456
 457                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 458
 459                 if (session->status == ISSL_HANDSHAKEN)
 460                 {
 461                         // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
 462                         // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
 463                         int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);
 464
 465                         if (ret == 0)
 466                         {
 467                                 // Client closed connection.
 468                                 readresult = 0;
 469                                 CloseSession(session);
 470                                 return 1;
 471                         }
 472                         else if (ret < 0)
 473                         {
 474                                 if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 475                                 {
 476                                         errno = EAGAIN;
 477                                         return -1;
 478                                 }
 479                                 else
 480                                 {
 481                                         readresult = 0;
 482                                         CloseSession(session);
 483                                 }
 484                         }
 485                         else
 486                         {
 487                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 488                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 489                                 // 'buffer' is 'count' long
 490
 491                                 unsigned int length = ret + session->inbufoffset;
 492
 493                                 if(count <= length)
 494                                 {
 495                                         memcpy(buffer, session->inbuf, count);
 496                                         // Move the stuff left in inbuf to the beginning of it
 497                                         memcpy(session->inbuf, session->inbuf + count, (length - count));
 498                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 499                                         session->inbufoffset = length - count;
 500                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 501                                         readresult = count;
 502                                 }
 503                                 else
 504                                 {
 505                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 506                                         memcpy(buffer, session->inbuf, length);
 507                                         // Zero the offset, as there's nothing there..
 508                                         session->inbufoffset = 0;
 509                                         // As above
 510                                         readresult = length;
 511                                 }
 512                         }
 513                 }
 514                 else if(session->status == ISSL_CLOSING)
 515                         readresult = 0;
 516
 517                 return 1;
 518         }
 519
 520         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 521         {
 522                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 523                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 524                         return 0;
 525
 526                 issl_session* session = &sessions[fd];
 527                 const char* sendbuffer = buffer;
 528
 529                 if (!session->sess)
 530                 {
 531                         CloseSession(session);
 532                         return 1;
 533                 }
 534
 535                 session->outbuf.append(sendbuffer, count);
 536                 sendbuffer = session->outbuf.c_str();
 537                 count = session->outbuf.size();
 538
 539                 if (session->status == ISSL_HANDSHAKING_WRITE)
 540                 {
 541                         // The handshake isn't finished, try to finish it.
 542                         Handshake(session);
 543                         errno = EAGAIN;
 544                         return -1;
 545                 }
 546
 547                 int ret = 0;
 548
 549                 if (session->status == ISSL_HANDSHAKEN)
 550                 {
 551                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 552
 553                         if (ret == 0)
 554                         {
 555                                 CloseSession(session);
 556                         }
 557                         else if (ret < 0)
 558                         {
 559                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 560                                 {
 561                                         CloseSession(session);
 562                                 }
 563                                 else
 564                                 {
 565                                         errno = EAGAIN;
 566                                 }
 567                         }
 568                         else
 569                         {
 570                                 session->outbuf = session->outbuf.substr(ret);
 571                         }
 572                 }
 573
 574                 MakePollWrite(session);
 575
 576                 /* Who's smart idea was it to return 1 when we havent written anything?
 577                  * This fucks the buffer up in BufferedSocket :p
 578                  */
 579                 return ret < 1 ? 0 : ret;
 580         }
 581
 582         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 583         virtual void OnWhois(User* source, User* dest)
 584         {
 585                 if (!clientactive)
 586                         return;
 587
 588                 // Bugfix, only send this numeric for *our* SSL users
 589                 if(dest->GetExt("ssl", dummy) || (IS_LOCAL(dest) &&  isin(dest->GetPort(), listenports)))
 590                 {
 591                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick, dest->nick);
 592                 }
 593         }
 594
 595         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 596         {
 597                 // check if the linking module wants to know about OUR metadata
 598                 if(extname == "ssl")
 599                 {
 600                         // check if this user has an swhois field to send
 601                         if(user->GetExt(extname, dummy))
 602                         {
 603                                 // call this function in the linking module, let it format the data how it
 604                                 // sees fit, and send it on its way. We dont need or want to know how.
 605                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 606                         }
 607                 }
 608         }
 609
 610         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 611         {
 612                 // check if its our metadata key, and its associated with a user
 613                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 614                 {
 615                         User* dest = (User*)target;
 616                         // if they dont already have an ssl flag, accept the remote server's
 617                         if (!dest->GetExt(extname, dummy))
 618                         {
 619                                 dest->Extend(extname, "ON");
 620                         }
 621                 }
 622         }
 623
 624         bool Handshake(issl_session* session)
 625         {
 626                 int ret = gnutls_handshake(session->sess);
 627
 628                 if (ret < 0)
 629                 {
 630                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 631                         {
 632                                 // Handshake needs resuming later, read() or write() would have blocked.
 633
 634                                 if(gnutls_record_get_direction(session->sess) == 0)
 635                                 {
 636                                         // gnutls_handshake() wants to read() again.
 637                                         session->status = ISSL_HANDSHAKING_READ;
 638                                 }
 639                                 else
 640                                 {
 641                                         // gnutls_handshake() wants to write() again.
 642                                         session->status = ISSL_HANDSHAKING_WRITE;
 643                                         MakePollWrite(session);
 644                                 }
 645                         }
 646                         else
 647                         {
 648                                 // Handshake failed.
 649                                 CloseSession(session);
 650                                 session->status = ISSL_CLOSING;
 651                         }
 652
 653                         return false;
 654                 }
 655                 else
 656                 {
 657                         // Handshake complete.
 658                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 659                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 660                         if (extendme)
 661                         {
 662                                 if (!extendme->GetExt("ssl", dummy))
 663                                         extendme->Extend("ssl", "ON");
 664                         }
 665
 666                         // Change the seesion state
 667                         session->status = ISSL_HANDSHAKEN;
 668
 669                         // Finish writing, if any left
 670                         MakePollWrite(session);
 671
 672                         return true;
 673                 }
 674         }
 675
 676         virtual void OnPostConnect(User* user)
 677         {
 678                 // This occurs AFTER OnUserConnect so we can be sure the
 679                 // protocol module has propagated the NICK message.
 680                 if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
 681                 {
 682                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 683                         std::deque<std::string>* metadata = new std::deque<std::string>;
 684                         metadata->push_back(user->nick);
 685                         metadata->push_back("ssl");             // The metadata id
 686                         metadata->push_back("ON");              // The value to send
 687                         Event* event = new Event((char*)metadata,(Module*)this,"send_metadata");
 688                         event->Send(ServerInstance);            // Trigger the event. We don't care what module picks it up.
 689                         delete event;
 690                         delete metadata;
 691
 692                         VerifyCertificate(&sessions[user->GetFd()],user);
 693                         if (sessions[user->GetFd()].sess)
 694                         {
 695                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 696                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 697                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 698                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick, cipher.c_str());
 699                         }
 700                 }
 701         }
 702
 703         void MakePollWrite(issl_session* session)
 704         {
 705                 //OnRawSocketWrite(session->fd, NULL, 0);
 706                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 707                 if (eh)
 708                         ServerInstance->SE->WantWrite(eh);
 709         }
 710
 711         virtual void OnBufferFlushed(User* user)
 712         {
 713                 if (user->GetExt("ssl"))
 714                 {
 715                         issl_session* session = &sessions[user->GetFd()];
 716                         if (session && session->outbuf.size())
 717                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 718                 }
 719         }
 720
 721         void CloseSession(issl_session* session)
 722         {
 723                 if(session->sess)
 724                 {
 725                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 726                         gnutls_deinit(session->sess);
 727                 }
 728
 729                 if(session->inbuf)
 730                 {
 731                         delete[] session->inbuf;
 732                 }
 733
 734                 session->outbuf.clear();
 735                 session->inbuf = NULL;
 736                 session->sess = NULL;
 737                 session->status = ISSL_NONE;
 738         }
 739
 740         void VerifyCertificate(issl_session* session, Extensible* user)
 741         {
 742                 if (!session->sess || !user)
 743                         return;
 744
 745                 unsigned int status;
 746                 const gnutls_datum_t* cert_list;
 747                 int ret;
 748                 unsigned int cert_list_size;
 749                 gnutls_x509_crt_t cert;
 750                 char name[MAXBUF];
 751                 unsigned char digest[MAXBUF];
 752                 size_t digest_size = sizeof(digest);
 753                 size_t name_size = sizeof(name);
 754                 ssl_cert* certinfo = new ssl_cert;
 755
 756                 user->Extend("ssl_cert",certinfo);
 757
 758                 /* This verification function uses the trusted CAs in the credentials
 759                  * structure. So you must have installed one or more CA certificates.
 760                  */
 761                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 762
 763                 if (ret < 0)
 764                 {
 765                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 766                         return;
 767                 }
 768
 769                 if (status & GNUTLS_CERT_INVALID)
 770                 {
 771                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 772                 }
 773                 else
 774                 {
 775                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 776                 }
 777                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 778                 {
 779                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 780                 }
 781                 else
 782                 {
 783                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 784                 }
 785                 if (status & GNUTLS_CERT_REVOKED)
 786                 {
 787                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 788                 }
 789                 else
 790                 {
 791                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 792                 }
 793                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 794                 {
 795                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 796                 }
 797                 else
 798                 {
 799                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 800                 }
 801
 802                 /* Up to here the process is the same for X.509 certificates and
 803                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 804                  * be easily extended to work with openpgp keys as well.
 805                  */
 806                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 807                 {
 808                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 809                         return;
 810                 }
 811
 812                 ret = gnutls_x509_crt_init(&cert);
 813                 if (ret < 0)
 814                 {
 815                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 816                         return;
 817                 }
 818
 819                 cert_list_size = 0;
 820                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 821                 if (cert_list == NULL)
 822                 {
 823                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 824                         return;
 825                 }
 826
 827                 /* This is not a real world example, since we only check the first
 828                  * certificate in the given chain.
 829                  */
 830
 831                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 832                 if (ret < 0)
 833                 {
 834                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 835                         return;
 836                 }
 837
 838                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 839
 840                 certinfo->data.insert(std::make_pair("dn",name));
 841
 842                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 843
 844                 certinfo->data.insert(std::make_pair("issuer",name));
 845
 846                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 847                 {
 848                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 849                 }
 850                 else
 851                 {
 852                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 853                 }
 854
 855                 /* Beware here we do not check for errors.
 856                  */
 857                 if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
 858                 {
 859                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 860                 }
 861
 862                 gnutls_x509_crt_deinit(cert);
 863
 864                 return;
 865         }
 866
 867 };
 868
 869 MODULE_INIT(ModuleSSLGnuTLS)