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