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->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
  87                                 user->io = Caller;
  88                                 Caller->OnRawSocketAccept(user->GetFd(), user->GetIPString(), user->GetPort());
  89                         }
  90                         else
  91                                 user->WriteNumeric(671, "%s :STARTTLS failure", user->nick.c_str());
  92                 }
  93
  94                 return CMD_FAILURE;
  95         }
  96 };
  97
  98 class ModuleSSLGnuTLS : public Module
  99 {
 100
 101         ConfigReader* Conf;
 102
 103         char* dummy;
 104
 105         std::vector<std::string> listenports;
 106
 107         int inbufsize;
 108         issl_session* sessions;
 109
 110         gnutls_certificate_credentials x509_cred;
 111         gnutls_dh_params dh_params;
 112
 113         std::string keyfile;
 114         std::string certfile;
 115         std::string cafile;
 116         std::string crlfile;
 117         std::string sslports;
 118         int dh_bits;
 119
 120         int clientactive;
 121
 122         CommandStartTLS* starttls;
 123
 124  public:
 125
 126         ModuleSSLGnuTLS(InspIRCd* Me)
 127                 : Module(Me)
 128         {
 129                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 130
 131                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 132
 133                 // Not rehashable...because I cba to reduce all the sizes of existing buffers.
 134                 inbufsize = ServerInstance->Config->NetBufferSize;
 135
 136                 gnutls_global_init(); // This must be called once in the program
 137
 138                 if(gnutls_certificate_allocate_credentials(&x509_cred) != 0)
 139                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials");
 140
 141                 // Guessing return meaning
 142                 if(gnutls_dh_params_init(&dh_params) < 0)
 143                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters");
 144
 145                 // Needs the flag as it ignores a plain /rehash
 146                 OnRehash(NULL,"ssl");
 147
 148                 // Void return, guess we assume success
 149                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 150                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 151                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData, I_OnUnloadModule, I_OnRehash, I_OnWhois, I_OnPostConnect, I_OnEvent, I_OnHookUserIO };
 152                 ServerInstance->Modules->Attach(eventlist, this, 17);
 153
 154                 starttls = new CommandStartTLS(ServerInstance, this);
 155                 ServerInstance->AddCommand(starttls);
 156         }
 157
 158         virtual void OnRehash(User* user, const std::string &param)
 159         {
 160                 Conf = new ConfigReader(ServerInstance);
 161
 162                 listenports.clear();
 163                 clientactive = 0;
 164                 sslports.clear();
 165
 166                 for(int index = 0; index < Conf->Enumerate("bind"); index++)
 167                 {
 168                         // For each <bind> tag
 169                         std::string x = Conf->ReadValue("bind", "type", index);
 170                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", index) == "gnutls"))
 171                         {
 172                                 // Get the port we're meant to be listening on with SSL
 173                                 std::string port = Conf->ReadValue("bind", "port", index);
 174                                 std::string addr = Conf->ReadValue("bind", "address", index);
 175
 176                                 irc::portparser portrange(port, false);
 177                                 long portno = -1;
 178                                 while ((portno = portrange.GetToken()))
 179                                 {
 180                                         clientactive++;
 181                                         try
 182                                         {
 183                                                 listenports.push_back(addr + ":" + ConvToStr(portno));
 184
 185                                                 for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
 186                                                         if ((ServerInstance->Config->ports[i]->GetPort() == portno) && (ServerInstance->Config->ports[i]->GetIP() == addr))
 187                                                                 ServerInstance->Config->ports[i]->SetDescription("ssl");
 188                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %ld", portno);
 189
 190                                                 sslports.append((addr.empty() ? "*" : addr)).append(":").append(ConvToStr(portno)).append(";");
 191                                         }
 192                                         catch (ModuleException &e)
 193                                         {
 194                                                 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());
 195                                         }
 196                                 }
 197                         }
 198                 }
 199
 200                 if (!sslports.empty())
 201                         sslports.erase(sslports.end() - 1);
 202
 203                 if(param != "ssl")
 204                 {
 205                         delete Conf;
 206                         return;
 207                 }
 208
 209                 std::string confdir(ServerInstance->ConfigFileName);
 210                 // +1 so we the path ends with a /
 211                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 212
 213                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 214                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 215                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 216                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 217                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 218
 219                 // Set all the default values needed.
 220                 if (cafile.empty())
 221                         cafile = "ca.pem";
 222
 223                 if (crlfile.empty())
 224                         crlfile = "crl.pem";
 225
 226                 if (certfile.empty())
 227                         certfile = "cert.pem";
 228
 229                 if (keyfile.empty())
 230                         keyfile = "key.pem";
 231
 232                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 233                         dh_bits = 1024;
 234
 235                 // Prepend relative paths with the path to the config directory.
 236                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 237                         cafile = confdir + cafile;
 238
 239                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 240                         crlfile = confdir + crlfile;
 241
 242                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 243                         certfile = confdir + certfile;
 244
 245                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 246                         keyfile = confdir + keyfile;
 247
 248                 int ret;
 249
 250                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 251                         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));
 252
 253                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 254                         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));
 255
 256                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 257                 {
 258                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 259                         throw ModuleException("Unable to load GnuTLS server certificate: " + std::string(gnutls_strerror(ret)));
 260                 }
 261
 262                 // This may be on a large (once a day or week) timer eventually.
 263                 GenerateDHParams();
 264
 265                 delete Conf;
 266         }
 267
 268         void GenerateDHParams()
 269         {
 270                 // Generate Diffie Hellman parameters - for use with DHE
 271                 // kx algorithms. These should be discarded and regenerated
 272                 // once a day, once a week or once a month. Depending on the
 273                 // security requirements.
 274
 275                 int ret;
 276
 277                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 278                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 279         }
 280
 281         virtual ~ModuleSSLGnuTLS()
 282         {
 283                 gnutls_dh_params_deinit(dh_params);
 284                 gnutls_certificate_free_credentials(x509_cred);
 285                 gnutls_global_deinit();
 286                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 287                 delete[] sessions;
 288         }
 289
 290         virtual void OnCleanup(int target_type, void* item)
 291         {
 292                 if(target_type == TYPE_USER)
 293                 {
 294                         User* user = (User*)item;
 295
 296                         if(user->io)
 297                         {
 298                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 299                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 300                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 301                         }
 302                         if (user->GetExt("ssl_cert", dummy))
 303                         {
 304                                 ssl_cert* tofree;
 305                                 user->GetExt("ssl_cert", tofree);
 306                                 delete tofree;
 307                                 user->Shrink("ssl_cert");
 308                         }
 309
 310                         user->io = NULL;
 311                 }
 312         }
 313
 314         virtual void OnUnloadModule(Module* mod, const std::string &name)
 315         {
 316                 if(mod == this)
 317                 {
 318                         for(unsigned int i = 0; i < listenports.size(); i++)
 319                         {
 320                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 321                                         if (listenports[i] == (ServerInstance->Config->ports[j]->GetIP()+":"+ConvToStr(ServerInstance->Config->ports[j]->GetPort())))
 322                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 323                         }
 324                 }
 325         }
 326
 327         virtual Version GetVersion()
 328         {
 329                 return Version(1, 2, 0, 0, VF_VENDOR, API_VERSION);
 330         }
 331
 332
 333         virtual void On005Numeric(std::string &output)
 334         {
 335                 output.append(" SSL=" + sslports);
 336         }
 337
 338         virtual void OnHookUserIO(User* user, const std::string &targetip)
 339         {
 340                 if (!user->io && isin(targetip,user->GetPort(),listenports))
 341                 {
 342                         /* Hook the user with our module */
 343                         user->io = this;
 344                 }
 345         }
 346
 347         virtual const char* OnRequest(Request* request)
 348         {
 349                 ISHRequest* ISR = (ISHRequest*)request;
 350                 if (strcmp("IS_NAME", request->GetId()) == 0)
 351                 {
 352                         return "gnutls";
 353                 }
 354                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 355                 {
 356                         const char* ret = "OK";
 357                         try
 358                         {
 359                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 360                         }
 361                         catch (ModuleException &e)
 362                         {
 363                                 return NULL;
 364                         }
 365                         return ret;
 366                 }
 367                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 368                 {
 369                         return ServerInstance->Config->DelIOHook((BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 370                 }
 371                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 372                 {
 373                         if (ISR->Sock->GetFd() < 0)
 374                                 return "OK";
 375
 376                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 377                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 378                 }
 379                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 380                 {
 381                         if (ISR->Sock->GetFd() > -1)
 382                         {
 383                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 384                                 if (session->sess)
 385                                 {
 386                                         if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 387                                         {
 388                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 389                                                 return "OK";
 390                                         }
 391                                 }
 392                         }
 393                 }
 394                 return NULL;
 395         }
 396
 397
 398         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 399         {
 400                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 401                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 402                         return;
 403
 404                 issl_session* session = &sessions[fd];
 405
 406                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 407                 if (session->sess)
 408                         return;
 409
 410                 session->fd = fd;
 411                 session->inbuf = new char[inbufsize];
 412                 session->inbufoffset = 0;
 413
 414                 gnutls_init(&session->sess, GNUTLS_SERVER);
 415
 416                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 417                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 418                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 419
 420                 /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
 421                  * This needs testing, but it's easy enough to rollback if need be
 422                  * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 423                  * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
 424                  *
 425                  * With testing this seems to...not work :/
 426                  */
 427
 428                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 429
 430                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 431
 432                 Handshake(session);
 433         }
 434
 435         virtual void OnRawSocketConnect(int fd)
 436         {
 437                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 438                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 439                         return;
 440
 441                 issl_session* session = &sessions[fd];
 442
 443                 session->fd = fd;
 444                 session->inbuf = new char[inbufsize];
 445                 session->inbufoffset = 0;
 446
 447                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 448
 449                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 450                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 451                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 452                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 453
 454                 Handshake(session);
 455         }
 456
 457         virtual void OnRawSocketClose(int fd)
 458         {
 459                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 460                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 461                         return;
 462
 463                 CloseSession(&sessions[fd]);
 464
 465                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 466
 467                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 468                 {
 469                         ssl_cert* tofree;
 470                         user->GetExt("ssl_cert", tofree);
 471                         delete tofree;
 472                         user->Shrink("ssl_cert");
 473                 }
 474         }
 475
 476         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 477         {
 478                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 479                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 480                         return 0;
 481
 482                 issl_session* session = &sessions[fd];
 483
 484                 if (!session->sess)
 485                 {
 486                         readresult = 0;
 487                         CloseSession(session);
 488                         return 1;
 489                 }
 490
 491                 if (session->status == ISSL_HANDSHAKING_READ)
 492                 {
 493                         // The handshake isn't finished, try to finish it.
 494
 495                         if(!Handshake(session))
 496                         {
 497                                 // Couldn't resume handshake.
 498                                 return -1;
 499                         }
 500                 }
 501                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 502                 {
 503                         errno = EAGAIN;
 504                         MakePollWrite(session);
 505                         return -1;
 506                 }
 507
 508                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 509
 510                 if (session->status == ISSL_HANDSHAKEN)
 511                 {
 512                         // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
 513                         // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
 514                         int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);
 515
 516                         if (ret == 0)
 517                         {
 518                                 // Client closed connection.
 519                                 readresult = 0;
 520                                 CloseSession(session);
 521                                 return 1;
 522                         }
 523                         else if (ret < 0)
 524                         {
 525                                 if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 526                                 {
 527                                         errno = EAGAIN;
 528                                         return -1;
 529                                 }
 530                                 else
 531                                 {
 532                                         readresult = 0;
 533                                         CloseSession(session);
 534                                 }
 535                         }
 536                         else
 537                         {
 538                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 539                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 540                                 // 'buffer' is 'count' long
 541
 542                                 unsigned int length = ret + session->inbufoffset;
 543
 544                                 if(count <= length)
 545                                 {
 546                                         memcpy(buffer, session->inbuf, count);
 547                                         // Move the stuff left in inbuf to the beginning of it
 548                                         memcpy(session->inbuf, session->inbuf + count, (length - count));
 549                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 550                                         session->inbufoffset = length - count;
 551                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 552                                         readresult = count;
 553                                 }
 554                                 else
 555                                 {
 556                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 557                                         memcpy(buffer, session->inbuf, length);
 558                                         // Zero the offset, as there's nothing there..
 559                                         session->inbufoffset = 0;
 560                                         // As above
 561                                         readresult = length;
 562                                 }
 563                         }
 564                 }
 565                 else if(session->status == ISSL_CLOSING)
 566                         readresult = 0;
 567
 568                 return 1;
 569         }
 570
 571         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 572         {
 573                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 574                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 575                         return 0;
 576
 577                 issl_session* session = &sessions[fd];
 578                 const char* sendbuffer = buffer;
 579
 580                 if (!session->sess)
 581                 {
 582                         CloseSession(session);
 583                         return 1;
 584                 }
 585
 586                 session->outbuf.append(sendbuffer, count);
 587                 sendbuffer = session->outbuf.c_str();
 588                 count = session->outbuf.size();
 589
 590                 if (session->status == ISSL_HANDSHAKING_WRITE)
 591                 {
 592                         // The handshake isn't finished, try to finish it.
 593                         Handshake(session);
 594                         errno = EAGAIN;
 595                         return -1;
 596                 }
 597
 598                 int ret = 0;
 599
 600                 if (session->status == ISSL_HANDSHAKEN)
 601                 {
 602                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 603
 604                         if (ret == 0)
 605                         {
 606                                 CloseSession(session);
 607                         }
 608                         else if (ret < 0)
 609                         {
 610                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 611                                 {
 612                                         CloseSession(session);
 613                                 }
 614                                 else
 615                                 {
 616                                         errno = EAGAIN;
 617                                 }
 618                         }
 619                         else
 620                         {
 621                                 session->outbuf = session->outbuf.substr(ret);
 622                         }
 623                 }
 624
 625                 MakePollWrite(session);
 626
 627                 /* Who's smart idea was it to return 1 when we havent written anything?
 628                  * This fucks the buffer up in BufferedSocket :p
 629                  */
 630                 return ret < 1 ? 0 : ret;
 631         }
 632
 633         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 634         virtual void OnWhois(User* source, User* dest)
 635         {
 636                 if (!clientactive)
 637                         return;
 638
 639                 // Bugfix, only send this numeric for *our* SSL users
 640                 if (dest->GetExt("ssl", dummy) || ((IS_LOCAL(dest) && (dest->io == this))))
 641                 {
 642                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick.c_str(), dest->nick.c_str());
 643                 }
 644         }
 645
 646         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 647         {
 648                 // check if the linking module wants to know about OUR metadata
 649                 if(extname == "ssl")
 650                 {
 651                         // check if this user has an swhois field to send
 652                         if(user->GetExt(extname, dummy))
 653                         {
 654                                 // call this function in the linking module, let it format the data how it
 655                                 // sees fit, and send it on its way. We dont need or want to know how.
 656                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 657                         }
 658                 }
 659         }
 660
 661         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 662         {
 663                 // check if its our metadata key, and its associated with a user
 664                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 665                 {
 666                         User* dest = (User*)target;
 667                         // if they dont already have an ssl flag, accept the remote server's
 668                         if (!dest->GetExt(extname, dummy))
 669                         {
 670                                 dest->Extend(extname, "ON");
 671                         }
 672                 }
 673         }
 674
 675         bool Handshake(issl_session* session)
 676         {
 677                 int ret = gnutls_handshake(session->sess);
 678
 679                 if (ret < 0)
 680                 {
 681                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 682                         {
 683                                 // Handshake needs resuming later, read() or write() would have blocked.
 684
 685                                 if(gnutls_record_get_direction(session->sess) == 0)
 686                                 {
 687                                         // gnutls_handshake() wants to read() again.
 688                                         session->status = ISSL_HANDSHAKING_READ;
 689                                 }
 690                                 else
 691                                 {
 692                                         // gnutls_handshake() wants to write() again.
 693                                         session->status = ISSL_HANDSHAKING_WRITE;
 694                                         MakePollWrite(session);
 695                                 }
 696                         }
 697                         else
 698                         {
 699                                 // Handshake failed.
 700                                 CloseSession(session);
 701                                 session->status = ISSL_CLOSING;
 702                         }
 703
 704                         return false;
 705                 }
 706                 else
 707                 {
 708                         // Handshake complete.
 709                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 710                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 711                         if (extendme)
 712                         {
 713                                 if (!extendme->GetExt("ssl", dummy))
 714                                         extendme->Extend("ssl", "ON");
 715                         }
 716
 717                         // Change the seesion state
 718                         session->status = ISSL_HANDSHAKEN;
 719
 720                         // Finish writing, if any left
 721                         MakePollWrite(session);
 722
 723                         return true;
 724                 }
 725         }
 726
 727         virtual void OnPostConnect(User* user)
 728         {
 729                 // This occurs AFTER OnUserConnect so we can be sure the
 730                 // protocol module has propagated the NICK message.
 731                 if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
 732                 {
 733                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 734                         ServerInstance->PI->SendMetaData(user, TYPE_USER, "SSL", "on");
 735
 736                         VerifyCertificate(&sessions[user->GetFd()],user);
 737                         if (sessions[user->GetFd()].sess)
 738                         {
 739                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 740                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 741                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 742                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 743                         }
 744                 }
 745         }
 746
 747         void MakePollWrite(issl_session* session)
 748         {
 749                 //OnRawSocketWrite(session->fd, NULL, 0);
 750                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 751                 if (eh)
 752                         ServerInstance->SE->WantWrite(eh);
 753         }
 754
 755         virtual void OnBufferFlushed(User* user)
 756         {
 757                 if (user->GetExt("ssl"))
 758                 {
 759                         issl_session* session = &sessions[user->GetFd()];
 760                         if (session && session->outbuf.size())
 761                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 762                 }
 763         }
 764
 765         void CloseSession(issl_session* session)
 766         {
 767                 if(session->sess)
 768                 {
 769                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 770                         gnutls_deinit(session->sess);
 771                 }
 772
 773                 if(session->inbuf)
 774                 {
 775                         delete[] session->inbuf;
 776                 }
 777
 778                 session->outbuf.clear();
 779                 session->inbuf = NULL;
 780                 session->sess = NULL;
 781                 session->status = ISSL_NONE;
 782         }
 783
 784         void VerifyCertificate(issl_session* session, Extensible* user)
 785         {
 786                 if (!session->sess || !user)
 787                         return;
 788
 789                 unsigned int status;
 790                 const gnutls_datum_t* cert_list;
 791                 int ret;
 792                 unsigned int cert_list_size;
 793                 gnutls_x509_crt_t cert;
 794                 char name[MAXBUF];
 795                 unsigned char digest[MAXBUF];
 796                 size_t digest_size = sizeof(digest);
 797                 size_t name_size = sizeof(name);
 798                 ssl_cert* certinfo = new ssl_cert;
 799
 800                 user->Extend("ssl_cert",certinfo);
 801
 802                 /* This verification function uses the trusted CAs in the credentials
 803                  * structure. So you must have installed one or more CA certificates.
 804                  */
 805                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 806
 807                 if (ret < 0)
 808                 {
 809                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 810                         return;
 811                 }
 812
 813                 if (status & GNUTLS_CERT_INVALID)
 814                 {
 815                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 816                 }
 817                 else
 818                 {
 819                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 820                 }
 821                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 822                 {
 823                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 824                 }
 825                 else
 826                 {
 827                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 828                 }
 829                 if (status & GNUTLS_CERT_REVOKED)
 830                 {
 831                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 832                 }
 833                 else
 834                 {
 835                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 836                 }
 837                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 838                 {
 839                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 840                 }
 841                 else
 842                 {
 843                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 844                 }
 845
 846                 /* Up to here the process is the same for X.509 certificates and
 847                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 848                  * be easily extended to work with openpgp keys as well.
 849                  */
 850                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 851                 {
 852                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 853                         return;
 854                 }
 855
 856                 ret = gnutls_x509_crt_init(&cert);
 857                 if (ret < 0)
 858                 {
 859                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 860                         return;
 861                 }
 862
 863                 cert_list_size = 0;
 864                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 865                 if (cert_list == NULL)
 866                 {
 867                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 868                         return;
 869                 }
 870
 871                 /* This is not a real world example, since we only check the first
 872                  * certificate in the given chain.
 873                  */
 874
 875                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 876                 if (ret < 0)
 877                 {
 878                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 879                         return;
 880                 }
 881
 882                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 883
 884                 certinfo->data.insert(std::make_pair("dn",name));
 885
 886                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 887
 888                 certinfo->data.insert(std::make_pair("issuer",name));
 889
 890                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 891                 {
 892                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 893                 }
 894                 else
 895                 {
 896                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 897                 }
 898
 899                 /* Beware here we do not check for errors.
 900                  */
 901                 if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
 902                 {
 903                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 904                 }
 905
 906                 gnutls_x509_crt_deinit(cert);
 907
 908                 return;
 909         }
 910
 911         void OnEvent(Event* ev)
 912         {
 913                 GenericCapHandler(ev, "tls", "tls");
 914         }
 915
 916         void Prioritize()
 917         {
 918                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 919                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIO_AFTER, &server);
 920         }
 921 };
 922
 923 MODULE_INIT(ModuleSSLGnuTLS)