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 #include "m_cap.h"
  28
  29 #ifdef WINDOWS
  30 #pragma comment(lib, "libgnutls-13.lib")
  31 #undef MAX_DESCRIPTORS
  32 #define MAX_DESCRIPTORS 10000
  33 #endif
  34
  35 /* $ModDesc: Provides SSL support for clients */
  36 /* $CompileFlags: exec("libgnutls-config --cflags") */
  37 /* $LinkerFlags: rpath("libgnutls-config --libs") exec("libgnutls-config --libs") */
  38 /* $ModDep: transport.h */
  39 /* $CopyInstall: conf/key.pem $(CONPATH) */
  40 /* $CopyInstall: conf/cert.pem $(CONPATH) */
  41
  42 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  43
  44 bool isin(const std::string &host, int port, const std::vector<std::string> &portlist)
  45 {
  46         if (std::find(portlist.begin(), portlist.end(), "*:" + ConvToStr(port)) != portlist.end())
  47                 return true;
  48
  49         if (std::find(portlist.begin(), portlist.end(), ":" + ConvToStr(port)) != portlist.end())
  50                 return true;
  51
  52         return std::find(portlist.begin(), portlist.end(), host + ":" + ConvToStr(port)) != portlist.end();
  53 }
  54
  55 /** Represents an SSL user's extra data
  56  */
  57 class issl_session : public classbase
  58 {
  59 public:
  60         gnutls_session_t sess;
  61         issl_status status;
  62         std::string outbuf;
  63         int inbufoffset;
  64         char* inbuf;
  65         int fd;
  66 };
  67
  68 class CommandStartTLS : public Command
  69 {
  70         Module* Caller;
  71  public:
  72         /* Command 'dalinfo', takes no parameters and needs no special modes */
  73         CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance,"STARTTLS", 0, 0, true), Caller(mod)
  74         {
  75                 this->source = "m_ssl_gnutls.so";
  76         }
  77
  78         CmdResult Handle (const char* const* parameters, int pcnt, User *user)
  79         {
  80                 user->io = Caller;
  81                 Caller->OnRawSocketAccept(user->GetFd(), user->GetIPString(), user->GetPort());
  82
  83                 return CMD_FAILURE;
  84         }
  85 };
  86
  87 class ModuleSSLGnuTLS : public Module
  88 {
  89
  90         ConfigReader* Conf;
  91
  92         char* dummy;
  93
  94         std::vector<std::string> listenports;
  95
  96         int inbufsize;
  97         issl_session sessions[MAX_DESCRIPTORS];
  98
  99         gnutls_certificate_credentials x509_cred;
 100         gnutls_dh_params dh_params;
 101
 102         std::string keyfile;
 103         std::string certfile;
 104         std::string cafile;
 105         std::string crlfile;
 106         std::string sslports;
 107         int dh_bits;
 108
 109         int clientactive;
 110
 111         CommandStartTLS* starttls;
 112
 113  public:
 114
 115         ModuleSSLGnuTLS(InspIRCd* Me)
 116                 : Module(Me)
 117         {
 118                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 119
 120                 // Not rehashable...because I cba to reduce all the sizes of existing buffers.
 121                 inbufsize = ServerInstance->Config->NetBufferSize;
 122
 123                 gnutls_global_init(); // This must be called once in the program
 124
 125                 if(gnutls_certificate_allocate_credentials(&x509_cred) != 0)
 126                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials");
 127
 128                 // Guessing return meaning
 129                 if(gnutls_dh_params_init(&dh_params) < 0)
 130                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters");
 131
 132                 // Needs the flag as it ignores a plain /rehash
 133                 OnRehash(NULL,"ssl");
 134
 135                 // Void return, guess we assume success
 136                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 137                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 138                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData, I_OnUnloadModule, I_OnRehash, I_OnWhois, I_OnPostConnect, I_OnEvent, I_OnHookUserIO };
 139                 ServerInstance->Modules->Attach(eventlist, this, 17);
 140
 141                 starttls = new CommandStartTLS(ServerInstance, this);
 142                 ServerInstance->AddCommand(starttls);
 143         }
 144
 145         virtual void OnRehash(User* user, const std::string &param)
 146         {
 147                 Conf = new ConfigReader(ServerInstance);
 148
 149                 listenports.clear();
 150                 clientactive = 0;
 151                 sslports.clear();
 152
 153                 for(int index = 0; index < Conf->Enumerate("bind"); index++)
 154                 {
 155                         // For each <bind> tag
 156                         std::string x = Conf->ReadValue("bind", "type", index);
 157                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", index) == "gnutls"))
 158                         {
 159                                 // Get the port we're meant to be listening on with SSL
 160                                 std::string port = Conf->ReadValue("bind", "port", index);
 161                                 std::string addr = Conf->ReadValue("bind", "address", index);
 162
 163                                 irc::portparser portrange(port, false);
 164                                 long portno = -1;
 165                                 while ((portno = portrange.GetToken()))
 166                                 {
 167                                         clientactive++;
 168                                         try
 169                                         {
 170                                                 listenports.push_back(addr + ":" + ConvToStr(portno));
 171
 172                                                 for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
 173                                                         if ((ServerInstance->Config->ports[i]->GetPort() == portno) && (ServerInstance->Config->ports[i]->GetIP() == addr))
 174                                                                 ServerInstance->Config->ports[i]->SetDescription("ssl");
 175                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %d", portno);
 176
 177                                                 sslports.append((addr.empty() ? "*" : addr)).append(":").append(ConvToStr(portno)).append(";");
 178                                         }
 179                                         catch (ModuleException &e)
 180                                         {
 181                                                 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());
 182                                         }
 183                                 }
 184                         }
 185                 }
 186
 187                 if (!sslports.empty())
 188                         sslports.erase(sslports.end() - 1);
 189
 190                 if(param != "ssl")
 191                 {
 192                         delete Conf;
 193                         return;
 194                 }
 195
 196                 std::string confdir(ServerInstance->ConfigFileName);
 197                 // +1 so we the path ends with a /
 198                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 199
 200                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 201                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 202                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 203                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 204                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 205
 206                 // Set all the default values needed.
 207                 if (cafile.empty())
 208                         cafile = "ca.pem";
 209
 210                 if (crlfile.empty())
 211                         crlfile = "crl.pem";
 212
 213                 if (certfile.empty())
 214                         certfile = "cert.pem";
 215
 216                 if (keyfile.empty())
 217                         keyfile = "key.pem";
 218
 219                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 220                         dh_bits = 1024;
 221
 222                 // Prepend relative paths with the path to the config directory.
 223                 if(cafile[0] != '/')
 224                         cafile = confdir + cafile;
 225
 226                 if(crlfile[0] != '/')
 227                         crlfile = confdir + crlfile;
 228
 229                 if(certfile[0] != '/')
 230                         certfile = confdir + certfile;
 231
 232                 if(keyfile[0] != '/')
 233                         keyfile = confdir + keyfile;
 234
 235                 int ret;
 236
 237                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 238                         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));
 239
 240                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 241                         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));
 242
 243                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 244                 {
 245                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 246                         throw ModuleException("Unable to load GnuTLS server certificate: " + std::string(gnutls_strerror(ret)));
 247                 }
 248
 249                 // This may be on a large (once a day or week) timer eventually.
 250                 GenerateDHParams();
 251
 252                 delete Conf;
 253         }
 254
 255         void GenerateDHParams()
 256         {
 257                 // Generate Diffie Hellman parameters - for use with DHE
 258                 // kx algorithms. These should be discarded and regenerated
 259                 // once a day, once a week or once a month. Depending on the
 260                 // security requirements.
 261
 262                 int ret;
 263
 264                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 265                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 266         }
 267
 268         virtual ~ModuleSSLGnuTLS()
 269         {
 270                 gnutls_dh_params_deinit(dh_params);
 271                 gnutls_certificate_free_credentials(x509_cred);
 272                 gnutls_global_deinit();
 273         }
 274
 275         virtual void OnCleanup(int target_type, void* item)
 276         {
 277                 if(target_type == TYPE_USER)
 278                 {
 279                         User* user = (User*)item;
 280
 281                         if(user->io)
 282                         {
 283                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 284                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 285                                 User::QuitUser(ServerInstance, user, "SSL module unloading");
 286                         }
 287                         if (user->GetExt("ssl_cert", dummy))
 288                         {
 289                                 ssl_cert* tofree;
 290                                 user->GetExt("ssl_cert", tofree);
 291                                 delete tofree;
 292                                 user->Shrink("ssl_cert");
 293                         }
 294
 295                         user->io = NULL;
 296                 }
 297         }
 298
 299         virtual void OnUnloadModule(Module* mod, const std::string &name)
 300         {
 301                 if(mod == this)
 302                 {
 303                         for(unsigned int i = 0; i < listenports.size(); i++)
 304                         {
 305                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 306                                         if (listenports[i] == (ServerInstance->Config->ports[j]->GetIP()+":"+ConvToStr(ServerInstance->Config->ports[j]->GetPort())))
 307                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 308                         }
 309                 }
 310         }
 311
 312         virtual Version GetVersion()
 313         {
 314                 return Version(1, 2, 0, 0, VF_VENDOR, API_VERSION);
 315         }
 316
 317
 318         virtual void On005Numeric(std::string &output)
 319         {
 320                 output.append(" SSL=" + sslports);
 321         }
 322
 323         virtual void OnHookUserIO(User* user, const std::string &targetip)
 324         {
 325                 if (!user->io && isin(targetip,user->GetPort(),listenports))
 326                 {
 327                         /* Hook the user with our module */
 328                         user->io = this;
 329                 }
 330         }
 331
 332         virtual const char* OnRequest(Request* request)
 333         {
 334                 ISHRequest* ISR = (ISHRequest*)request;
 335                 if (strcmp("IS_NAME", request->GetId()) == 0)
 336                 {
 337                         return "gnutls";
 338                 }
 339                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 340                 {
 341                         const char* ret = "OK";
 342                         try
 343                         {
 344                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 345                         }
 346                         catch (ModuleException &e)
 347                         {
 348                                 return NULL;
 349                         }
 350                         return ret;
 351                 }
 352                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 353                 {
 354                         return ServerInstance->Config->DelIOHook((BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 355                 }
 356                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 357                 {
 358                         if (ISR->Sock->GetFd() < 0)
 359                                 return "OK";
 360
 361                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 362                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 363                 }
 364                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 365                 {
 366                         if (ISR->Sock->GetFd() > -1)
 367                         {
 368                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 369                                 if (session->sess)
 370                                 {
 371                                         if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 372                                         {
 373                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 374                                                 return "OK";
 375                                         }
 376                                 }
 377                         }
 378                 }
 379                 return NULL;
 380         }
 381
 382
 383         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 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_SERVER);
 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
 401                 /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
 402                  * This needs testing, but it's easy enough to rollback if need be
 403                  * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 404                  * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
 405                  *
 406                  * With testing this seems to...not work :/
 407                  */
 408
 409                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 410
 411                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 412
 413                 Handshake(session);
 414         }
 415
 416         virtual void OnRawSocketConnect(int fd)
 417         {
 418                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 419                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 420                         return;
 421
 422                 issl_session* session = &sessions[fd];
 423
 424                 session->fd = fd;
 425                 session->inbuf = new char[inbufsize];
 426                 session->inbufoffset = 0;
 427
 428                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 429
 430                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 431                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 432                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 433                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 434
 435                 Handshake(session);
 436         }
 437
 438         virtual void OnRawSocketClose(int fd)
 439         {
 440                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 441                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 442                         return;
 443
 444                 CloseSession(&sessions[fd]);
 445
 446                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 447
 448                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 449                 {
 450                         ssl_cert* tofree;
 451                         user->GetExt("ssl_cert", tofree);
 452                         delete tofree;
 453                         user->Shrink("ssl_cert");
 454                 }
 455         }
 456
 457         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 458         {
 459                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 460                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 461                         return 0;
 462
 463                 issl_session* session = &sessions[fd];
 464
 465                 if (!session->sess)
 466                 {
 467                         readresult = 0;
 468                         CloseSession(session);
 469                         return 1;
 470                 }
 471
 472                 if (session->status == ISSL_HANDSHAKING_READ)
 473                 {
 474                         // The handshake isn't finished, try to finish it.
 475
 476                         if(!Handshake(session))
 477                         {
 478                                 // Couldn't resume handshake.
 479                                 return -1;
 480                         }
 481                 }
 482                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 483                 {
 484                         errno = EAGAIN;
 485                         MakePollWrite(session);
 486                         return -1;
 487                 }
 488
 489                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 490
 491                 if (session->status == ISSL_HANDSHAKEN)
 492                 {
 493                         // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
 494                         // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
 495                         int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);
 496
 497                         if (ret == 0)
 498                         {
 499                                 // Client closed connection.
 500                                 readresult = 0;
 501                                 CloseSession(session);
 502                                 return 1;
 503                         }
 504                         else if (ret < 0)
 505                         {
 506                                 if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 507                                 {
 508                                         errno = EAGAIN;
 509                                         return -1;
 510                                 }
 511                                 else
 512                                 {
 513                                         readresult = 0;
 514                                         CloseSession(session);
 515                                 }
 516                         }
 517                         else
 518                         {
 519                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 520                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 521                                 // 'buffer' is 'count' long
 522
 523                                 unsigned int length = ret + session->inbufoffset;
 524
 525                                 if(count <= length)
 526                                 {
 527                                         memcpy(buffer, session->inbuf, count);
 528                                         // Move the stuff left in inbuf to the beginning of it
 529                                         memcpy(session->inbuf, session->inbuf + count, (length - count));
 530                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 531                                         session->inbufoffset = length - count;
 532                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 533                                         readresult = count;
 534                                 }
 535                                 else
 536                                 {
 537                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 538                                         memcpy(buffer, session->inbuf, length);
 539                                         // Zero the offset, as there's nothing there..
 540                                         session->inbufoffset = 0;
 541                                         // As above
 542                                         readresult = length;
 543                                 }
 544                         }
 545                 }
 546                 else if(session->status == ISSL_CLOSING)
 547                         readresult = 0;
 548
 549                 return 1;
 550         }
 551
 552         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 553         {
 554                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 555                 if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 556                         return 0;
 557
 558                 issl_session* session = &sessions[fd];
 559                 const char* sendbuffer = buffer;
 560
 561                 if (!session->sess)
 562                 {
 563                         CloseSession(session);
 564                         return 1;
 565                 }
 566
 567                 session->outbuf.append(sendbuffer, count);
 568                 sendbuffer = session->outbuf.c_str();
 569                 count = session->outbuf.size();
 570
 571                 if (session->status == ISSL_HANDSHAKING_WRITE)
 572                 {
 573                         // The handshake isn't finished, try to finish it.
 574                         Handshake(session);
 575                         errno = EAGAIN;
 576                         return -1;
 577                 }
 578
 579                 int ret = 0;
 580
 581                 if (session->status == ISSL_HANDSHAKEN)
 582                 {
 583                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 584
 585                         if (ret == 0)
 586                         {
 587                                 CloseSession(session);
 588                         }
 589                         else if (ret < 0)
 590                         {
 591                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 592                                 {
 593                                         CloseSession(session);
 594                                 }
 595                                 else
 596                                 {
 597                                         errno = EAGAIN;
 598                                 }
 599                         }
 600                         else
 601                         {
 602                                 session->outbuf = session->outbuf.substr(ret);
 603                         }
 604                 }
 605
 606                 MakePollWrite(session);
 607
 608                 /* Who's smart idea was it to return 1 when we havent written anything?
 609                  * This fucks the buffer up in BufferedSocket :p
 610                  */
 611                 return ret < 1 ? 0 : ret;
 612         }
 613
 614         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 615         virtual void OnWhois(User* source, User* dest)
 616         {
 617                 if (!clientactive)
 618                         return;
 619
 620                 // Bugfix, only send this numeric for *our* SSL users
 621                 if (dest->GetExt("ssl", dummy) || ((IS_LOCAL(dest) && (dest->io == this))))
 622                 {
 623                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick, dest->nick);
 624                 }
 625         }
 626
 627         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 628         {
 629                 // check if the linking module wants to know about OUR metadata
 630                 if(extname == "ssl")
 631                 {
 632                         // check if this user has an swhois field to send
 633                         if(user->GetExt(extname, dummy))
 634                         {
 635                                 // call this function in the linking module, let it format the data how it
 636                                 // sees fit, and send it on its way. We dont need or want to know how.
 637                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 638                         }
 639                 }
 640         }
 641
 642         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 643         {
 644                 // check if its our metadata key, and its associated with a user
 645                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 646                 {
 647                         User* dest = (User*)target;
 648                         // if they dont already have an ssl flag, accept the remote server's
 649                         if (!dest->GetExt(extname, dummy))
 650                         {
 651                                 dest->Extend(extname, "ON");
 652                         }
 653                 }
 654         }
 655
 656         bool Handshake(issl_session* session)
 657         {
 658                 int ret = gnutls_handshake(session->sess);
 659
 660                 if (ret < 0)
 661                 {
 662                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 663                         {
 664                                 // Handshake needs resuming later, read() or write() would have blocked.
 665
 666                                 if(gnutls_record_get_direction(session->sess) == 0)
 667                                 {
 668                                         // gnutls_handshake() wants to read() again.
 669                                         session->status = ISSL_HANDSHAKING_READ;
 670                                 }
 671                                 else
 672                                 {
 673                                         // gnutls_handshake() wants to write() again.
 674                                         session->status = ISSL_HANDSHAKING_WRITE;
 675                                         MakePollWrite(session);
 676                                 }
 677                         }
 678                         else
 679                         {
 680                                 // Handshake failed.
 681                                 CloseSession(session);
 682                                 session->status = ISSL_CLOSING;
 683                         }
 684
 685                         return false;
 686                 }
 687                 else
 688                 {
 689                         // Handshake complete.
 690                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 691                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 692                         if (extendme)
 693                         {
 694                                 if (!extendme->GetExt("ssl", dummy))
 695                                         extendme->Extend("ssl", "ON");
 696                         }
 697
 698                         // Change the seesion state
 699                         session->status = ISSL_HANDSHAKEN;
 700
 701                         // Finish writing, if any left
 702                         MakePollWrite(session);
 703
 704                         return true;
 705                 }
 706         }
 707
 708         virtual void OnPostConnect(User* user)
 709         {
 710                 // This occurs AFTER OnUserConnect so we can be sure the
 711                 // protocol module has propagated the NICK message.
 712                 if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
 713                 {
 714                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 715                         std::deque<std::string>* metadata = new std::deque<std::string>;
 716                         metadata->push_back(user->nick);
 717                         metadata->push_back("ssl");             // The metadata id
 718                         metadata->push_back("ON");              // The value to send
 719                         Event* event = new Event((char*)metadata,(Module*)this,"send_metadata");
 720                         event->Send(ServerInstance);            // Trigger the event. We don't care what module picks it up.
 721                         delete event;
 722                         delete metadata;
 723
 724                         VerifyCertificate(&sessions[user->GetFd()],user);
 725                         if (sessions[user->GetFd()].sess)
 726                         {
 727                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 728                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 729                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 730                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick, cipher.c_str());
 731                         }
 732                 }
 733         }
 734
 735         void MakePollWrite(issl_session* session)
 736         {
 737                 //OnRawSocketWrite(session->fd, NULL, 0);
 738                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 739                 if (eh)
 740                         ServerInstance->SE->WantWrite(eh);
 741         }
 742
 743         virtual void OnBufferFlushed(User* user)
 744         {
 745                 if (user->GetExt("ssl"))
 746                 {
 747                         issl_session* session = &sessions[user->GetFd()];
 748                         if (session && session->outbuf.size())
 749                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 750                 }
 751         }
 752
 753         void CloseSession(issl_session* session)
 754         {
 755                 if(session->sess)
 756                 {
 757                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 758                         gnutls_deinit(session->sess);
 759                 }
 760
 761                 if(session->inbuf)
 762                 {
 763                         delete[] session->inbuf;
 764                 }
 765
 766                 session->outbuf.clear();
 767                 session->inbuf = NULL;
 768                 session->sess = NULL;
 769                 session->status = ISSL_NONE;
 770         }
 771
 772         void VerifyCertificate(issl_session* session, Extensible* user)
 773         {
 774                 if (!session->sess || !user)
 775                         return;
 776
 777                 unsigned int status;
 778                 const gnutls_datum_t* cert_list;
 779                 int ret;
 780                 unsigned int cert_list_size;
 781                 gnutls_x509_crt_t cert;
 782                 char name[MAXBUF];
 783                 unsigned char digest[MAXBUF];
 784                 size_t digest_size = sizeof(digest);
 785                 size_t name_size = sizeof(name);
 786                 ssl_cert* certinfo = new ssl_cert;
 787
 788                 user->Extend("ssl_cert",certinfo);
 789
 790                 /* This verification function uses the trusted CAs in the credentials
 791                  * structure. So you must have installed one or more CA certificates.
 792                  */
 793                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 794
 795                 if (ret < 0)
 796                 {
 797                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 798                         return;
 799                 }
 800
 801                 if (status & GNUTLS_CERT_INVALID)
 802                 {
 803                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 804                 }
 805                 else
 806                 {
 807                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 808                 }
 809                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 810                 {
 811                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 812                 }
 813                 else
 814                 {
 815                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 816                 }
 817                 if (status & GNUTLS_CERT_REVOKED)
 818                 {
 819                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 820                 }
 821                 else
 822                 {
 823                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 824                 }
 825                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 826                 {
 827                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 828                 }
 829                 else
 830                 {
 831                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 832                 }
 833
 834                 /* Up to here the process is the same for X.509 certificates and
 835                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 836                  * be easily extended to work with openpgp keys as well.
 837                  */
 838                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 839                 {
 840                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 841                         return;
 842                 }
 843
 844                 ret = gnutls_x509_crt_init(&cert);
 845                 if (ret < 0)
 846                 {
 847                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 848                         return;
 849                 }
 850
 851                 cert_list_size = 0;
 852                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 853                 if (cert_list == NULL)
 854                 {
 855                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 856                         return;
 857                 }
 858
 859                 /* This is not a real world example, since we only check the first
 860                  * certificate in the given chain.
 861                  */
 862
 863                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 864                 if (ret < 0)
 865                 {
 866                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 867                         return;
 868                 }
 869
 870                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 871
 872                 certinfo->data.insert(std::make_pair("dn",name));
 873
 874                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 875
 876                 certinfo->data.insert(std::make_pair("issuer",name));
 877
 878                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 879                 {
 880                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 881                 }
 882                 else
 883                 {
 884                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 885                 }
 886
 887                 /* Beware here we do not check for errors.
 888                  */
 889                 if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
 890                 {
 891                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 892                 }
 893
 894                 gnutls_x509_crt_deinit(cert);
 895
 896                 return;
 897         }
 898
 899         void OnEvent(Event* ev)
 900         {
 901                 GenericCapHandler(ev, "tls", "tls");
 902         }
 903
 904 };
 905
 906 MODULE_INIT(ModuleSSLGnuTLS)