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 #endif
  32
  33 /* $ModDesc: Provides SSL support for clients */
  34 /* $CompileFlags: exec("libgnutls-config --cflags") */
  35 /* $LinkerFlags: rpath("libgnutls-config --libs") exec("libgnutls-config --libs") */
  36 /* $ModDep: transport.h */
  37 /* $CopyInstall: conf/key.pem $(CONPATH) */
  38 /* $CopyInstall: conf/cert.pem $(CONPATH) */
  39
  40 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  41
  42 bool isin(const std::string &host, int port, const std::vector<std::string> &portlist)
  43 {
  44         if (std::find(portlist.begin(), portlist.end(), "*:" + ConvToStr(port)) != portlist.end())
  45                 return true;
  46
  47         if (std::find(portlist.begin(), portlist.end(), ":" + ConvToStr(port)) != portlist.end())
  48                 return true;
  49
  50         return std::find(portlist.begin(), portlist.end(), host + ":" + ConvToStr(port)) != portlist.end();
  51 }
  52
  53 /** Represents an SSL user's extra data
  54  */
  55 class issl_session : public classbase
  56 {
  57 public:
  58         gnutls_session_t sess;
  59         issl_status status;
  60         std::string outbuf;
  61         int inbufoffset;
  62         char* inbuf;
  63         int fd;
  64 };
  65
  66 class CommandStartTLS : public Command
  67 {
  68         Module* Caller;
  69  public:
  70         /* Command 'dalinfo', takes no parameters and needs no special modes */
  71         CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance,"STARTTLS", 0, 0, true), Caller(mod)
  72         {
  73                 this->source = "m_ssl_gnutls.so";
  74         }
  75
  76         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  77         {
  78                 if (user->registered == REG_ALL)
  79                 {
  80                         ServerInstance->Users->QuitUser(user, "STARTTLS not allowed after client registration");
  81                 }
  82                 else
  83                 {
  84                         if (!user->io)
  85                         {
  86                                 user->io = Caller;
  87                                 Caller->OnRawSocketAccept(user->GetFd(), user->GetIPString(), user->GetPort());
  88                         }
  89                 }
  90
  91                 return CMD_FAILURE;
  92         }
  93 };
  94
  95 class ModuleSSLGnuTLS : public Module
  96 {
  97
  98         ConfigReader* Conf;
  99
 100         char* dummy;
 101
 102         std::vector<std::string> listenports;
 103
 104         int inbufsize;
 105         issl_session* sessions;
 106
 107         gnutls_certificate_credentials x509_cred;
 108         gnutls_dh_params dh_params;
 109
 110         std::string keyfile;
 111         std::string certfile;
 112         std::string cafile;
 113         std::string crlfile;
 114         std::string sslports;
 115         int dh_bits;
 116
 117         int clientactive;
 118
 119         CommandStartTLS* starttls;
 120
 121  public:
 122
 123         ModuleSSLGnuTLS(InspIRCd* Me)
 124                 : Module(Me)
 125         {
 126                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 127
 128                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 129
 130                 // Not rehashable...because I cba to reduce all the sizes of existing buffers.
 131                 inbufsize = ServerInstance->Config->NetBufferSize;
 132
 133                 gnutls_global_init(); // This must be called once in the program
 134
 135                 if(gnutls_certificate_allocate_credentials(&x509_cred) != 0)
 136                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials");
 137
 138                 // Guessing return meaning
 139                 if(gnutls_dh_params_init(&dh_params) < 0)
 140                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters");
 141
 142                 // Needs the flag as it ignores a plain /rehash
 143                 OnRehash(NULL,"ssl");
 144
 145                 // Void return, guess we assume success
 146                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 147                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 148                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData, I_OnUnloadModule, I_OnRehash, I_OnWhois, I_OnPostConnect, I_OnEvent, I_OnHookUserIO };
 149                 ServerInstance->Modules->Attach(eventlist, this, 17);
 150
 151                 starttls = new CommandStartTLS(ServerInstance, this);
 152                 ServerInstance->AddCommand(starttls);
 153         }
 154
 155         virtual void OnRehash(User* user, const std::string &param)
 156         {
 157                 Conf = new ConfigReader(ServerInstance);
 158
 159                 listenports.clear();
 160                 clientactive = 0;
 161                 sslports.clear();
 162
 163                 for(int index = 0; index < Conf->Enumerate("bind"); index++)
 164                 {
 165                         // For each <bind> tag
 166                         std::string x = Conf->ReadValue("bind", "type", index);
 167                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", index) == "gnutls"))
 168                         {
 169                                 // Get the port we're meant to be listening on with SSL
 170                                 std::string port = Conf->ReadValue("bind", "port", index);
 171                                 std::string addr = Conf->ReadValue("bind", "address", index);
 172
 173                                 irc::portparser portrange(port, false);
 174                                 long portno = -1;
 175                                 while ((portno = portrange.GetToken()))
 176                                 {
 177                                         clientactive++;
 178                                         try
 179                                         {
 180                                                 listenports.push_back(addr + ":" + ConvToStr(portno));
 181
 182                                                 for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
 183                                                         if ((ServerInstance->Config->ports[i]->GetPort() == portno) && (ServerInstance->Config->ports[i]->GetIP() == addr))
 184                                                                 ServerInstance->Config->ports[i]->SetDescription("ssl");
 185                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %ld", portno);
 186
 187                                                 sslports.append((addr.empty() ? "*" : addr)).append(":").append(ConvToStr(portno)).append(";");
 188                                         }
 189                                         catch (ModuleException &e)
 190                                         {
 191                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: FAILED to enable SSL on port %ld: %s. Maybe it's already hooked by the same port on a different IP, or you have an other SSL or similar module loaded?", portno, e.GetReason());
 192                                         }
 193                                 }
 194                         }
 195                 }
 196
 197                 if (!sslports.empty())
 198                         sslports.erase(sslports.end() - 1);
 199
 200                 if(param != "ssl")
 201                 {
 202                         delete Conf;
 203                         return;
 204                 }
 205
 206                 std::string confdir(ServerInstance->ConfigFileName);
 207                 // +1 so we the path ends with a /
 208                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 209
 210                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 211                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 212                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 213                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 214                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 215
 216                 // Set all the default values needed.
 217                 if (cafile.empty())
 218                         cafile = "ca.pem";
 219
 220                 if (crlfile.empty())
 221                         crlfile = "crl.pem";
 222
 223                 if (certfile.empty())
 224                         certfile = "cert.pem";
 225
 226                 if (keyfile.empty())
 227                         keyfile = "key.pem";
 228
 229                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 230                         dh_bits = 1024;
 231
 232                 // Prepend relative paths with the path to the config directory.
 233                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 234                         cafile = confdir + cafile;
 235
 236                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 237                         crlfile = confdir + crlfile;
 238
 239                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 240                         certfile = confdir + certfile;
 241
 242                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 243                         keyfile = confdir + keyfile;
 244
 245                 int ret;
 246
 247                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 248                         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));
 249
 250                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 251                         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));
 252
 253                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 254                 {
 255                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 256                         throw ModuleException("Unable to load GnuTLS server certificate: " + std::string(gnutls_strerror(ret)));
 257                 }
 258
 259                 // This may be on a large (once a day or week) timer eventually.
 260                 GenerateDHParams();
 261
 262                 delete Conf;
 263         }
 264
 265         void GenerateDHParams()
 266         {
 267                 // Generate Diffie Hellman parameters - for use with DHE
 268                 // kx algorithms. These should be discarded and regenerated
 269                 // once a day, once a week or once a month. Depending on the
 270                 // security requirements.
 271
 272                 int ret;
 273
 274                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 275                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 276         }
 277
 278         virtual ~ModuleSSLGnuTLS()
 279         {
 280                 gnutls_dh_params_deinit(dh_params);
 281                 gnutls_certificate_free_credentials(x509_cred);
 282                 gnutls_global_deinit();
 283                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 284                 delete[] sessions;
 285         }
 286
 287         virtual void OnCleanup(int target_type, void* item)
 288         {
 289                 if(target_type == TYPE_USER)
 290                 {
 291                         User* user = (User*)item;
 292
 293                         if(user->io)
 294                         {
 295                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 296                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 297                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 298                         }
 299                         if (user->GetExt("ssl_cert", dummy))
 300                         {
 301                                 ssl_cert* tofree;
 302                                 user->GetExt("ssl_cert", tofree);
 303                                 delete tofree;
 304                                 user->Shrink("ssl_cert");
 305                         }
 306
 307                         user->io = NULL;
 308                 }
 309         }
 310
 311         virtual void OnUnloadModule(Module* mod, const std::string &name)
 312         {
 313                 if(mod == this)
 314                 {
 315                         for(unsigned int i = 0; i < listenports.size(); i++)
 316                         {
 317                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 318                                         if (listenports[i] == (ServerInstance->Config->ports[j]->GetIP()+":"+ConvToStr(ServerInstance->Config->ports[j]->GetPort())))
 319                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 320                         }
 321                 }
 322         }
 323
 324         virtual Version GetVersion()
 325         {
 326                 return Version(1, 2, 0, 0, VF_VENDOR, API_VERSION);
 327         }
 328
 329
 330         virtual void On005Numeric(std::string &output)
 331         {
 332                 output.append(" SSL=" + sslports);
 333         }
 334
 335         virtual void OnHookUserIO(User* user, const std::string &targetip)
 336         {
 337                 if (!user->io && isin(targetip,user->GetPort(),listenports))
 338                 {
 339                         /* Hook the user with our module */
 340                         user->io = this;
 341                 }
 342         }
 343
 344         virtual const char* OnRequest(Request* request)
 345         {
 346                 ISHRequest* ISR = (ISHRequest*)request;
 347                 if (strcmp("IS_NAME", request->GetId()) == 0)
 348                 {
 349                         return "gnutls";
 350                 }
 351                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 352                 {
 353                         const char* ret = "OK";
 354                         try
 355                         {
 356                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 357                         }
 358                         catch (ModuleException &e)
 359                         {
 360                                 return NULL;
 361                         }
 362                         return ret;
 363                 }
 364                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 365                 {
 366                         return ServerInstance->Config->DelIOHook((BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 367                 }
 368                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 369                 {
 370                         if (ISR->Sock->GetFd() < 0)
 371                                 return "OK";
 372
 373                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 374                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 375                 }
 376                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 377                 {
 378                         if (ISR->Sock->GetFd() > -1)
 379                         {
 380                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 381                                 if (session->sess)
 382                                 {
 383                                         if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 384                                         {
 385                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 386                                                 return "OK";
 387                                         }
 388                                 }
 389                         }
 390                 }
 391                 return NULL;
 392         }
 393
 394
 395         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 396         {
 397                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 398                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 399                         return;
 400
 401                 issl_session* session = &sessions[fd];
 402
 403                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 404                 if (session->sess)
 405                         return;
 406
 407                 session->fd = fd;
 408                 session->inbuf = new char[inbufsize];
 409                 session->inbufoffset = 0;
 410
 411                 gnutls_init(&session->sess, GNUTLS_SERVER);
 412
 413                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 414                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 415                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 416
 417                 /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
 418                  * This needs testing, but it's easy enough to rollback if need be
 419                  * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 420                  * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
 421                  *
 422                  * With testing this seems to...not work :/
 423                  */
 424
 425                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 426
 427                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 428
 429                 Handshake(session);
 430         }
 431
 432         virtual void OnRawSocketConnect(int fd)
 433         {
 434                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 435                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 436                         return;
 437
 438                 issl_session* session = &sessions[fd];
 439
 440                 session->fd = fd;
 441                 session->inbuf = new char[inbufsize];
 442                 session->inbufoffset = 0;
 443
 444                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 445
 446                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 447                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 448                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 449                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 450
 451                 Handshake(session);
 452         }
 453
 454         virtual void OnRawSocketClose(int fd)
 455         {
 456                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 457                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 458                         return;
 459
 460                 CloseSession(&sessions[fd]);
 461
 462                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 463
 464                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 465                 {
 466                         ssl_cert* tofree;
 467                         user->GetExt("ssl_cert", tofree);
 468                         delete tofree;
 469                         user->Shrink("ssl_cert");
 470                 }
 471         }
 472
 473         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 474         {
 475                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 476                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 477                         return 0;
 478
 479                 issl_session* session = &sessions[fd];
 480
 481                 if (!session->sess)
 482                 {
 483                         readresult = 0;
 484                         CloseSession(session);
 485                         return 1;
 486                 }
 487
 488                 if (session->status == ISSL_HANDSHAKING_READ)
 489                 {
 490                         // The handshake isn't finished, try to finish it.
 491
 492                         if(!Handshake(session))
 493                         {
 494                                 // Couldn't resume handshake.
 495                                 return -1;
 496                         }
 497                 }
 498                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 499                 {
 500                         errno = EAGAIN;
 501                         MakePollWrite(session);
 502                         return -1;
 503                 }
 504
 505                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 506
 507                 if (session->status == ISSL_HANDSHAKEN)
 508                 {
 509                         // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
 510                         // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
 511                         int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);
 512
 513                         if (ret == 0)
 514                         {
 515                                 // Client closed connection.
 516                                 readresult = 0;
 517                                 CloseSession(session);
 518                                 return 1;
 519                         }
 520                         else if (ret < 0)
 521                         {
 522                                 if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 523                                 {
 524                                         errno = EAGAIN;
 525                                         return -1;
 526                                 }
 527                                 else
 528                                 {
 529                                         readresult = 0;
 530                                         CloseSession(session);
 531                                 }
 532                         }
 533                         else
 534                         {
 535                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 536                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 537                                 // 'buffer' is 'count' long
 538
 539                                 unsigned int length = ret + session->inbufoffset;
 540
 541                                 if(count <= length)
 542                                 {
 543                                         memcpy(buffer, session->inbuf, count);
 544                                         // Move the stuff left in inbuf to the beginning of it
 545                                         memcpy(session->inbuf, session->inbuf + count, (length - count));
 546                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 547                                         session->inbufoffset = length - count;
 548                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 549                                         readresult = count;
 550                                 }
 551                                 else
 552                                 {
 553                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 554                                         memcpy(buffer, session->inbuf, length);
 555                                         // Zero the offset, as there's nothing there..
 556                                         session->inbufoffset = 0;
 557                                         // As above
 558                                         readresult = length;
 559                                 }
 560                         }
 561                 }
 562                 else if(session->status == ISSL_CLOSING)
 563                         readresult = 0;
 564
 565                 return 1;
 566         }
 567
 568         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 569         {
 570                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 571                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 572                         return 0;
 573
 574                 issl_session* session = &sessions[fd];
 575                 const char* sendbuffer = buffer;
 576
 577                 if (!session->sess)
 578                 {
 579                         CloseSession(session);
 580                         return 1;
 581                 }
 582
 583                 session->outbuf.append(sendbuffer, count);
 584                 sendbuffer = session->outbuf.c_str();
 585                 count = session->outbuf.size();
 586
 587                 if (session->status == ISSL_HANDSHAKING_WRITE)
 588                 {
 589                         // The handshake isn't finished, try to finish it.
 590                         Handshake(session);
 591                         errno = EAGAIN;
 592                         return -1;
 593                 }
 594
 595                 int ret = 0;
 596
 597                 if (session->status == ISSL_HANDSHAKEN)
 598                 {
 599                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 600
 601                         if (ret == 0)
 602                         {
 603                                 CloseSession(session);
 604                         }
 605                         else if (ret < 0)
 606                         {
 607                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 608                                 {
 609                                         CloseSession(session);
 610                                 }
 611                                 else
 612                                 {
 613                                         errno = EAGAIN;
 614                                 }
 615                         }
 616                         else
 617                         {
 618                                 session->outbuf = session->outbuf.substr(ret);
 619                         }
 620                 }
 621
 622                 MakePollWrite(session);
 623
 624                 /* Who's smart idea was it to return 1 when we havent written anything?
 625                  * This fucks the buffer up in BufferedSocket :p
 626                  */
 627                 return ret < 1 ? 0 : ret;
 628         }
 629
 630         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 631         virtual void OnWhois(User* source, User* dest)
 632         {
 633                 if (!clientactive)
 634                         return;
 635
 636                 // Bugfix, only send this numeric for *our* SSL users
 637                 if (dest->GetExt("ssl", dummy) || ((IS_LOCAL(dest) && (dest->io == this))))
 638                 {
 639                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick.c_str(), dest->nick.c_str());
 640                 }
 641         }
 642
 643         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 644         {
 645                 // check if the linking module wants to know about OUR metadata
 646                 if(extname == "ssl")
 647                 {
 648                         // check if this user has an swhois field to send
 649                         if(user->GetExt(extname, dummy))
 650                         {
 651                                 // call this function in the linking module, let it format the data how it
 652                                 // sees fit, and send it on its way. We dont need or want to know how.
 653                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 654                         }
 655                 }
 656         }
 657
 658         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 659         {
 660                 // check if its our metadata key, and its associated with a user
 661                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 662                 {
 663                         User* dest = (User*)target;
 664                         // if they dont already have an ssl flag, accept the remote server's
 665                         if (!dest->GetExt(extname, dummy))
 666                         {
 667                                 dest->Extend(extname, "ON");
 668                         }
 669                 }
 670         }
 671
 672         bool Handshake(issl_session* session)
 673         {
 674                 int ret = gnutls_handshake(session->sess);
 675
 676                 if (ret < 0)
 677                 {
 678                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 679                         {
 680                                 // Handshake needs resuming later, read() or write() would have blocked.
 681
 682                                 if(gnutls_record_get_direction(session->sess) == 0)
 683                                 {
 684                                         // gnutls_handshake() wants to read() again.
 685                                         session->status = ISSL_HANDSHAKING_READ;
 686                                 }
 687                                 else
 688                                 {
 689                                         // gnutls_handshake() wants to write() again.
 690                                         session->status = ISSL_HANDSHAKING_WRITE;
 691                                         MakePollWrite(session);
 692                                 }
 693                         }
 694                         else
 695                         {
 696                                 // Handshake failed.
 697                                 CloseSession(session);
 698                                 session->status = ISSL_CLOSING;
 699                         }
 700
 701                         return false;
 702                 }
 703                 else
 704                 {
 705                         // Handshake complete.
 706                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 707                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 708                         if (extendme)
 709                         {
 710                                 if (!extendme->GetExt("ssl", dummy))
 711                                         extendme->Extend("ssl", "ON");
 712                         }
 713
 714                         // Change the seesion state
 715                         session->status = ISSL_HANDSHAKEN;
 716
 717                         // Finish writing, if any left
 718                         MakePollWrite(session);
 719
 720                         return true;
 721                 }
 722         }
 723
 724         virtual void OnPostConnect(User* user)
 725         {
 726                 // This occurs AFTER OnUserConnect so we can be sure the
 727                 // protocol module has propagated the NICK message.
 728                 if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
 729                 {
 730                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 731                         ServerInstance->PI->SendMetaData(user, TYPE_USER, "SSL", "on");
 732
 733                         VerifyCertificate(&sessions[user->GetFd()],user);
 734                         if (sessions[user->GetFd()].sess)
 735                         {
 736                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 737                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 738                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 739                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 740                         }
 741                 }
 742         }
 743
 744         void MakePollWrite(issl_session* session)
 745         {
 746                 //OnRawSocketWrite(session->fd, NULL, 0);
 747                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 748                 if (eh)
 749                         ServerInstance->SE->WantWrite(eh);
 750         }
 751
 752         virtual void OnBufferFlushed(User* user)
 753         {
 754                 if (user->GetExt("ssl"))
 755                 {
 756                         issl_session* session = &sessions[user->GetFd()];
 757                         if (session && session->outbuf.size())
 758                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 759                 }
 760         }
 761
 762         void CloseSession(issl_session* session)
 763         {
 764                 if(session->sess)
 765                 {
 766                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 767                         gnutls_deinit(session->sess);
 768                 }
 769
 770                 if(session->inbuf)
 771                 {
 772                         delete[] session->inbuf;
 773                 }
 774
 775                 session->outbuf.clear();
 776                 session->inbuf = NULL;
 777                 session->sess = NULL;
 778                 session->status = ISSL_NONE;
 779         }
 780
 781         void VerifyCertificate(issl_session* session, Extensible* user)
 782         {
 783                 if (!session->sess || !user)
 784                         return;
 785
 786                 unsigned int status;
 787                 const gnutls_datum_t* cert_list;
 788                 int ret;
 789                 unsigned int cert_list_size;
 790                 gnutls_x509_crt_t cert;
 791                 char name[MAXBUF];
 792                 unsigned char digest[MAXBUF];
 793                 size_t digest_size = sizeof(digest);
 794                 size_t name_size = sizeof(name);
 795                 ssl_cert* certinfo = new ssl_cert;
 796
 797                 user->Extend("ssl_cert",certinfo);
 798
 799                 /* This verification function uses the trusted CAs in the credentials
 800                  * structure. So you must have installed one or more CA certificates.
 801                  */
 802                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 803
 804                 if (ret < 0)
 805                 {
 806                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 807                         return;
 808                 }
 809
 810                 if (status & GNUTLS_CERT_INVALID)
 811                 {
 812                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 813                 }
 814                 else
 815                 {
 816                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 817                 }
 818                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 819                 {
 820                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 821                 }
 822                 else
 823                 {
 824                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 825                 }
 826                 if (status & GNUTLS_CERT_REVOKED)
 827                 {
 828                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 829                 }
 830                 else
 831                 {
 832                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 833                 }
 834                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 835                 {
 836                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 837                 }
 838                 else
 839                 {
 840                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 841                 }
 842
 843                 /* Up to here the process is the same for X.509 certificates and
 844                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 845                  * be easily extended to work with openpgp keys as well.
 846                  */
 847                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 848                 {
 849                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 850                         return;
 851                 }
 852
 853                 ret = gnutls_x509_crt_init(&cert);
 854                 if (ret < 0)
 855                 {
 856                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 857                         return;
 858                 }
 859
 860                 cert_list_size = 0;
 861                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 862                 if (cert_list == NULL)
 863                 {
 864                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 865                         return;
 866                 }
 867
 868                 /* This is not a real world example, since we only check the first
 869                  * certificate in the given chain.
 870                  */
 871
 872                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 873                 if (ret < 0)
 874                 {
 875                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 876                         return;
 877                 }
 878
 879                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 880
 881                 certinfo->data.insert(std::make_pair("dn",name));
 882
 883                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 884
 885                 certinfo->data.insert(std::make_pair("issuer",name));
 886
 887                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 888                 {
 889                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 890                 }
 891                 else
 892                 {
 893                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 894                 }
 895
 896                 /* Beware here we do not check for errors.
 897                  */
 898                 if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
 899                 {
 900                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 901                 }
 902
 903                 gnutls_x509_crt_deinit(cert);
 904
 905                 return;
 906         }
 907
 908         void OnEvent(Event* ev)
 909         {
 910                 GenericCapHandler(ev, "tls", "tls");
 911         }
 912
 913         void Prioritize()
 914         {
 915                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 916                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIO_AFTER, &server);
 917         }
 918 };
 919
 920 MODULE_INIT(ModuleSSLGnuTLS)