src/modules/extra/m_ssl_gnutls.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 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 #include <gnutls/gnutls.h>
  16 #include <gnutls/x509.h>
  17 #include "transport.h"
  18 #include "m_cap.h"
  19
  20 #ifdef WINDOWS
  21 #pragma comment(lib, "libgnutls-13.lib")
  22 #endif
  23
  24 /* $ModDesc: Provides SSL support for clients */
  25 /* $CompileFlags: exec("libgnutls-config --cflags") */
  26 /* $LinkerFlags: rpath("libgnutls-config --libs") exec("libgnutls-config --libs") */
  27 /* $ModDep: transport.h */
  28 /* $CopyInstall: conf/key.pem $(CONPATH) */
  29 /* $CopyInstall: conf/cert.pem $(CONPATH) */
  30
  31 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  32
  33 bool isin(const std::string &host, int port, const std::vector<std::string> &portlist)
  34 {
  35         if (std::find(portlist.begin(), portlist.end(), "*:" + ConvToStr(port)) != portlist.end())
  36                 return true;
  37
  38         if (std::find(portlist.begin(), portlist.end(), ":" + ConvToStr(port)) != portlist.end())
  39                 return true;
  40
  41         return std::find(portlist.begin(), portlist.end(), host + ":" + ConvToStr(port)) != portlist.end();
  42 }
  43
  44 /** Represents an SSL user's extra data
  45  */
  46 class issl_session : public classbase
  47 {
  48 public:
  49         issl_session()
  50         {
  51                 sess = NULL;
  52         }
  53
  54         gnutls_session_t sess;
  55         issl_status status;
  56         std::string outbuf;
  57         int inbufoffset;
  58         char* inbuf;
  59         int fd;
  60 };
  61
  62 class CommandStartTLS : public Command
  63 {
  64         Module* Caller;
  65  public:
  66         /* Command 'dalinfo', takes no parameters and needs no special modes */
  67         CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance,"STARTTLS", 0, 0, true), Caller(mod)
  68         {
  69                 this->source = "m_ssl_gnutls.so";
  70         }
  71
  72         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  73         {
  74                 /* changed from == REG_ALL to catch clients sending STARTTLS
  75                  * after NICK and USER but before OnUserConnect completes and
  76                  * give a proper error message (see bug #645) - dz
  77                  */
  78                 if (user->registered != REG_NONE)
  79                 {
  80                         ServerInstance->Users->QuitUser(user, "STARTTLS is not permitted after client registration has started");
  81                 }
  82                 else
  83                 {
  84                         if (!user->GetIOHook())
  85                         {
  86                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
  87                                 user->AddIOHook(Caller);
  88                                 Caller->OnRawSocketAccept(user->GetFd(), user->GetIPString(), user->GetPort());
  89                         }
  90                         else
  91                                 user->WriteNumeric(691, "%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         bool cred_alloc;
 122
 123         CommandStartTLS* starttls;
 124
 125  public:
 126
 127         ModuleSSLGnuTLS(InspIRCd* Me)
 128                 : Module(Me)
 129         {
 130                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 131
 132                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 133
 134                 // Not rehashable...because I cba to reduce all the sizes of existing buffers.
 135                 inbufsize = ServerInstance->Config->NetBufferSize;
 136
 137                 gnutls_global_init(); // This must be called once in the program
 138
 139                 cred_alloc = false;
 140                 // Needs the flag as it ignores a plain /rehash
 141                 OnRehash(NULL,"ssl");
 142
 143                 // Void return, guess we assume success
 144                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 145                 Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup,
 146                         I_OnBufferFlushed, I_OnRequest, I_OnSyncUserMetaData, I_OnDecodeMetaData, I_OnUnloadModule, I_OnRehash, I_OnWhois, I_OnPostConnect, I_OnEvent, I_OnHookUserIO };
 147                 ServerInstance->Modules->Attach(eventlist, this, 17);
 148
 149                 starttls = new CommandStartTLS(ServerInstance, this);
 150                 ServerInstance->AddCommand(starttls);
 151         }
 152
 153         virtual void OnRehash(User* user, const std::string &param)
 154         {
 155                 Conf = new ConfigReader(ServerInstance);
 156
 157                 listenports.clear();
 158                 clientactive = 0;
 159                 sslports.clear();
 160
 161                 for(int index = 0; index < Conf->Enumerate("bind"); index++)
 162                 {
 163                         // For each <bind> tag
 164                         std::string x = Conf->ReadValue("bind", "type", index);
 165                         if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", index) == "gnutls"))
 166                         {
 167                                 // Get the port we're meant to be listening on with SSL
 168                                 std::string port = Conf->ReadValue("bind", "port", index);
 169                                 std::string addr = Conf->ReadValue("bind", "address", index);
 170
 171                                 irc::portparser portrange(port, false);
 172                                 long portno = -1;
 173                                 while ((portno = portrange.GetToken()))
 174                                 {
 175                                         clientactive++;
 176                                         try
 177                                         {
 178                                                 listenports.push_back(addr + ":" + ConvToStr(portno));
 179
 180                                                 for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
 181                                                         if ((ServerInstance->Config->ports[i]->GetPort() == portno) && (ServerInstance->Config->ports[i]->GetIP() == addr))
 182                                                                 ServerInstance->Config->ports[i]->SetDescription("ssl");
 183                                                 ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %ld", portno);
 184
 185                                                 sslports.append((addr.empty() ? "*" : addr)).append(":").append(ConvToStr(portno)).append(";");
 186                                         }
 187                                         catch (ModuleException &e)
 188                                         {
 189                                                 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());
 190                                         }
 191                                 }
 192                         }
 193                 }
 194
 195                 if (!sslports.empty())
 196                         sslports.erase(sslports.end() - 1);
 197
 198                 if(param != "ssl")
 199                 {
 200                         delete Conf;
 201                         return;
 202                 }
 203
 204                 std::string confdir(ServerInstance->ConfigFileName);
 205                 // +1 so we the path ends with a /
 206                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 207
 208                 cafile  = Conf->ReadValue("gnutls", "cafile", 0);
 209                 crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
 210                 certfile        = Conf->ReadValue("gnutls", "certfile", 0);
 211                 keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
 212                 dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);
 213
 214                 // Set all the default values needed.
 215                 if (cafile.empty())
 216                         cafile = "ca.pem";
 217
 218                 if (crlfile.empty())
 219                         crlfile = "crl.pem";
 220
 221                 if (certfile.empty())
 222                         certfile = "cert.pem";
 223
 224                 if (keyfile.empty())
 225                         keyfile = "key.pem";
 226
 227                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 228                         dh_bits = 1024;
 229
 230                 // Prepend relative paths with the path to the config directory.
 231                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 232                         cafile = confdir + cafile;
 233
 234                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 235                         crlfile = confdir + crlfile;
 236
 237                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 238                         certfile = confdir + certfile;
 239
 240                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 241                         keyfile = confdir + keyfile;
 242
 243                 int ret;
 244
 245                 if (cred_alloc)
 246                 {
 247                         // Deallocate the old credentials
 248                         gnutls_dh_params_deinit(dh_params);
 249                         gnutls_certificate_free_credentials(x509_cred);
 250                 }
 251                 else
 252                         cred_alloc = true;
 253
 254                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 255                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 256
 257                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 258                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 259
 260                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 261                         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));
 262
 263                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 264                         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));
 265
 266                 if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 267                 {
 268                         // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 269                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + ", key: " + keyfile + "): " + std::string(gnutls_strerror(ret)));
 270                 }
 271
 272                 // This may be on a large (once a day or week) timer eventually.
 273                 GenerateDHParams();
 274
 275                 delete Conf;
 276         }
 277
 278         void GenerateDHParams()
 279         {
 280                 // Generate Diffie Hellman parameters - for use with DHE
 281                 // kx algorithms. These should be discarded and regenerated
 282                 // once a day, once a week or once a month. Depending on the
 283                 // security requirements.
 284
 285                 int ret;
 286
 287                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 288                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 289         }
 290
 291         virtual ~ModuleSSLGnuTLS()
 292         {
 293                 gnutls_dh_params_deinit(dh_params);
 294                 gnutls_certificate_free_credentials(x509_cred);
 295                 gnutls_global_deinit();
 296                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 297                 delete[] sessions;
 298         }
 299
 300         virtual void OnCleanup(int target_type, void* item)
 301         {
 302                 if(target_type == TYPE_USER)
 303                 {
 304                         User* user = (User*)item;
 305
 306                         if (user->GetIOHook() == this)
 307                         {
 308                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 309                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 310                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 311                                 user->DelIOHook();
 312                         }
 313                         if (user->GetExt("ssl_cert", dummy))
 314                         {
 315                                 ssl_cert* tofree;
 316                                 user->GetExt("ssl_cert", tofree);
 317                                 delete tofree;
 318                                 user->Shrink("ssl_cert");
 319                         }
 320                 }
 321         }
 322
 323         virtual void OnUnloadModule(Module* mod, const std::string &name)
 324         {
 325                 if(mod == this)
 326                 {
 327                         for(unsigned int i = 0; i < listenports.size(); i++)
 328                         {
 329                                 for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
 330                                         if (listenports[i] == (ServerInstance->Config->ports[j]->GetIP()+":"+ConvToStr(ServerInstance->Config->ports[j]->GetPort())))
 331                                                 ServerInstance->Config->ports[j]->SetDescription("plaintext");
 332                         }
 333                 }
 334         }
 335
 336         virtual Version GetVersion()
 337         {
 338                 return Version("$Id$", VF_VENDOR, API_VERSION);
 339         }
 340
 341
 342         virtual void On005Numeric(std::string &output)
 343         {
 344                 output.append(" SSL=" + sslports);
 345         }
 346
 347         virtual void OnHookUserIO(User* user, const std::string &targetip)
 348         {
 349                 if (!user->GetIOHook() && isin(targetip,user->GetPort(),listenports))
 350                 {
 351                         /* Hook the user with our module */
 352                         user->AddIOHook(this);
 353                 }
 354         }
 355
 356         virtual const char* OnRequest(Request* request)
 357         {
 358                 ISHRequest* ISR = (ISHRequest*)request;
 359                 if (strcmp("IS_NAME", request->GetId()) == 0)
 360                 {
 361                         return "gnutls";
 362                 }
 363                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 364                 {
 365                         const char* ret = "OK";
 366                         try
 367                         {
 368                                 ret = ISR->Sock->AddIOHook((Module*)this) ? "OK" : NULL;
 369                         }
 370                         catch (ModuleException &e)
 371                         {
 372                                 return NULL;
 373                         }
 374                         return ret;
 375                 }
 376                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 377                 {
 378                         return ISR->Sock->DelIOHook() ? "OK" : NULL;
 379                 }
 380                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 381                 {
 382                         if (ISR->Sock->GetFd() < 0)
 383                                 return "OK";
 384
 385                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 386                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 387                 }
 388                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 389                 {
 390                         if (ISR->Sock->GetFd() > -1)
 391                         {
 392                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 393                                 if (session->sess)
 394                                 {
 395                                         if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
 396                                         {
 397                                                 VerifyCertificate(session, (BufferedSocket*)ISR->Sock);
 398                                                 return "OK";
 399                                         }
 400                                 }
 401                         }
 402                 }
 403                 return NULL;
 404         }
 405
 406
 407         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 408         {
 409                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 410                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 411                         return;
 412
 413                 issl_session* session = &sessions[fd];
 414
 415                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 416                 if (session->sess)
 417                         return;
 418
 419                 session->fd = fd;
 420                 session->inbuf = new char[inbufsize];
 421                 session->inbufoffset = 0;
 422
 423                 gnutls_init(&session->sess, GNUTLS_SERVER);
 424
 425                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 426                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 427                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 428
 429                 /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
 430                  * This needs testing, but it's easy enough to rollback if need be
 431                  * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 432                  * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
 433                  *
 434                  * With testing this seems to...not work :/
 435                  */
 436
 437                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 438
 439                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 440
 441                 Handshake(session);
 442         }
 443
 444         virtual void OnRawSocketConnect(int fd)
 445         {
 446                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 447                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 448                         return;
 449
 450                 issl_session* session = &sessions[fd];
 451
 452                 session->fd = fd;
 453                 session->inbuf = new char[inbufsize];
 454                 session->inbufoffset = 0;
 455
 456                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 457
 458                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 459                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 460                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 461                 gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
 462
 463                 Handshake(session);
 464         }
 465
 466         virtual void OnRawSocketClose(int fd)
 467         {
 468                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 469                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds()))
 470                         return;
 471
 472                 CloseSession(&sessions[fd]);
 473
 474                 EventHandler* user = ServerInstance->SE->GetRef(fd);
 475
 476                 if ((user) && (user->GetExt("ssl_cert", dummy)))
 477                 {
 478                         ssl_cert* tofree;
 479                         user->GetExt("ssl_cert", tofree);
 480                         delete tofree;
 481                         user->Shrink("ssl_cert");
 482                 }
 483         }
 484
 485         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 486         {
 487                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 488                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 489                         return 0;
 490
 491                 issl_session* session = &sessions[fd];
 492
 493                 if (!session->sess)
 494                 {
 495                         readresult = 0;
 496                         CloseSession(session);
 497                         return 1;
 498                 }
 499
 500                 if (session->status == ISSL_HANDSHAKING_READ)
 501                 {
 502                         // The handshake isn't finished, try to finish it.
 503
 504                         if(!Handshake(session))
 505                         {
 506                                 // Couldn't resume handshake.
 507                                 return -1;
 508                         }
 509                 }
 510                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 511                 {
 512                         errno = EAGAIN;
 513                         MakePollWrite(session);
 514                         return -1;
 515                 }
 516
 517                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 518
 519                 if (session->status == ISSL_HANDSHAKEN)
 520                 {
 521                         // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
 522                         // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
 523                         int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);
 524
 525                         if (ret == 0)
 526                         {
 527                                 // Client closed connection.
 528                                 readresult = 0;
 529                                 CloseSession(session);
 530                                 return 1;
 531                         }
 532                         else if (ret < 0)
 533                         {
 534                                 if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 535                                 {
 536                                         errno = EAGAIN;
 537                                         return -1;
 538                                 }
 539                                 else
 540                                 {
 541                                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 542                                                         "m_ssl_gnutls.so: Error while reading on fd %d: %s",
 543                                                         session->fd, gnutls_strerror(ret));
 544                                         readresult = 0;
 545                                         CloseSession(session);
 546                                 }
 547                         }
 548                         else
 549                         {
 550                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 551                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 552                                 // 'buffer' is 'count' long
 553
 554                                 unsigned int length = ret + session->inbufoffset;
 555
 556                                 if(count <= length)
 557                                 {
 558                                         memcpy(buffer, session->inbuf, count);
 559                                         // Move the stuff left in inbuf to the beginning of it
 560                                         memmove(session->inbuf, session->inbuf + count, (length - count));
 561                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 562                                         session->inbufoffset = length - count;
 563                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 564                                         readresult = count;
 565                                 }
 566                                 else
 567                                 {
 568                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 569                                         memcpy(buffer, session->inbuf, length);
 570                                         // Zero the offset, as there's nothing there..
 571                                         session->inbufoffset = 0;
 572                                         // As above
 573                                         readresult = length;
 574                                 }
 575                         }
 576                 }
 577                 else if(session->status == ISSL_CLOSING)
 578                         readresult = 0;
 579
 580                 return 1;
 581         }
 582
 583         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 584         {
 585                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 586                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 587                         return 0;
 588
 589                 issl_session* session = &sessions[fd];
 590                 const char* sendbuffer = buffer;
 591
 592                 if (!session->sess)
 593                 {
 594                         CloseSession(session);
 595                         return 1;
 596                 }
 597
 598                 session->outbuf.append(sendbuffer, count);
 599                 sendbuffer = session->outbuf.c_str();
 600                 count = session->outbuf.size();
 601
 602                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 603                 {
 604                         // The handshake isn't finished, try to finish it.
 605                         Handshake(session);
 606                         errno = EAGAIN;
 607                         return -1;
 608                 }
 609
 610                 int ret = 0;
 611
 612                 if (session->status == ISSL_HANDSHAKEN)
 613                 {
 614                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 615
 616                         if (ret == 0)
 617                         {
 618                                 CloseSession(session);
 619                         }
 620                         else if (ret < 0)
 621                         {
 622                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 623                                 {
 624                                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 625                                                         "m_ssl_gnutls.so: Error while writing to fd %d: %s",
 626                                                         session->fd, gnutls_strerror(ret));
 627                                         CloseSession(session);
 628                                 }
 629                                 else
 630                                 {
 631                                         errno = EAGAIN;
 632                                 }
 633                         }
 634                         else
 635                         {
 636                                 session->outbuf = session->outbuf.substr(ret);
 637                         }
 638                 }
 639
 640                 MakePollWrite(session);
 641
 642                 /* Who's smart idea was it to return 1 when we havent written anything?
 643                  * This fucks the buffer up in BufferedSocket :p
 644                  */
 645                 return ret < 1 ? 0 : ret;
 646         }
 647
 648         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 649         virtual void OnWhois(User* source, User* dest)
 650         {
 651                 if (!clientactive)
 652                         return;
 653
 654                 // Bugfix, only send this numeric for *our* SSL users
 655                 if (dest->GetExt("ssl", dummy) || ((IS_LOCAL(dest) && (dest->GetIOHook() == this))))
 656                 {
 657                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick.c_str(), dest->nick.c_str());
 658                 }
 659         }
 660
 661         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 662         {
 663                 // check if the linking module wants to know about OUR metadata
 664                 if(extname == "ssl")
 665                 {
 666                         // check if this user has an swhois field to send
 667                         if(user->GetExt(extname, dummy))
 668                         {
 669                                 // call this function in the linking module, let it format the data how it
 670                                 // sees fit, and send it on its way. We dont need or want to know how.
 671                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 672                         }
 673                 }
 674         }
 675
 676         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 677         {
 678                 // check if its our metadata key, and its associated with a user
 679                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 680                 {
 681                         User* dest = (User*)target;
 682                         // if they dont already have an ssl flag, accept the remote server's
 683                         if (!dest->GetExt(extname, dummy))
 684                         {
 685                                 dest->Extend(extname, "ON");
 686                         }
 687                 }
 688         }
 689
 690         bool Handshake(issl_session* session)
 691         {
 692                 int ret = gnutls_handshake(session->sess);
 693
 694                 if (ret < 0)
 695                 {
 696                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 697                         {
 698                                 // Handshake needs resuming later, read() or write() would have blocked.
 699
 700                                 if(gnutls_record_get_direction(session->sess) == 0)
 701                                 {
 702                                         // gnutls_handshake() wants to read() again.
 703                                         session->status = ISSL_HANDSHAKING_READ;
 704                                 }
 705                                 else
 706                                 {
 707                                         // gnutls_handshake() wants to write() again.
 708                                         session->status = ISSL_HANDSHAKING_WRITE;
 709                                         MakePollWrite(session);
 710                                 }
 711                         }
 712                         else
 713                         {
 714                                 // Handshake failed.
 715                                 ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT,
 716                                                 "m_ssl_gnutls.so: Handshake failed on fd %d: %s",
 717                                                 session->fd, gnutls_strerror(ret));
 718                                 CloseSession(session);
 719                                 session->status = ISSL_CLOSING;
 720                         }
 721
 722                         return false;
 723                 }
 724                 else
 725                 {
 726                         // Handshake complete.
 727                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 728                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 729                         if (extendme)
 730                         {
 731                                 if (!extendme->GetExt("ssl", dummy))
 732                                         extendme->Extend("ssl", "ON");
 733                         }
 734
 735                         // Change the seesion state
 736                         session->status = ISSL_HANDSHAKEN;
 737
 738                         // Finish writing, if any left
 739                         MakePollWrite(session);
 740
 741                         return true;
 742                 }
 743         }
 744
 745         virtual void OnPostConnect(User* user)
 746         {
 747                 // This occurs AFTER OnUserConnect so we can be sure the
 748                 // protocol module has propagated the NICK message.
 749                 if (user->GetIOHook() == this && (IS_LOCAL(user)))
 750                 {
 751                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 752                         ServerInstance->PI->SendMetaData(user, TYPE_USER, "SSL", "on");
 753
 754                         VerifyCertificate(&sessions[user->GetFd()],user);
 755                         if (sessions[user->GetFd()].sess)
 756                         {
 757                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 758                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 759                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 760                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 761                         }
 762                 }
 763         }
 764
 765         void MakePollWrite(issl_session* session)
 766         {
 767                 //OnRawSocketWrite(session->fd, NULL, 0);
 768                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 769                 if (eh)
 770                         ServerInstance->SE->WantWrite(eh);
 771         }
 772
 773         virtual void OnBufferFlushed(User* user)
 774         {
 775                 if (user->GetIOHook() == this)
 776                 {
 777                         issl_session* session = &sessions[user->GetFd()];
 778                         if (session && session->outbuf.size())
 779                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 780                 }
 781         }
 782
 783         void CloseSession(issl_session* session)
 784         {
 785                 if(session->sess)
 786                 {
 787                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 788                         gnutls_deinit(session->sess);
 789                 }
 790
 791                 if(session->inbuf)
 792                 {
 793                         delete[] session->inbuf;
 794                 }
 795
 796                 session->outbuf.clear();
 797                 session->inbuf = NULL;
 798                 session->sess = NULL;
 799                 session->status = ISSL_NONE;
 800         }
 801
 802         void VerifyCertificate(issl_session* session, Extensible* user)
 803         {
 804                 if (!session->sess || !user)
 805                         return;
 806
 807                 unsigned int status;
 808                 const gnutls_datum_t* cert_list;
 809                 int ret;
 810                 unsigned int cert_list_size;
 811                 gnutls_x509_crt_t cert;
 812                 char name[MAXBUF];
 813                 unsigned char digest[MAXBUF];
 814                 size_t digest_size = sizeof(digest);
 815                 size_t name_size = sizeof(name);
 816                 ssl_cert* certinfo = new ssl_cert;
 817
 818                 user->Extend("ssl_cert",certinfo);
 819
 820                 /* This verification function uses the trusted CAs in the credentials
 821                  * structure. So you must have installed one or more CA certificates.
 822                  */
 823                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 824
 825                 if (ret < 0)
 826                 {
 827                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 828                         return;
 829                 }
 830
 831                 if (status & GNUTLS_CERT_INVALID)
 832                 {
 833                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 834                 }
 835                 else
 836                 {
 837                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 838                 }
 839                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 840                 {
 841                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 842                 }
 843                 else
 844                 {
 845                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 846                 }
 847                 if (status & GNUTLS_CERT_REVOKED)
 848                 {
 849                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 850                 }
 851                 else
 852                 {
 853                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 854                 }
 855                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 856                 {
 857                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 858                 }
 859                 else
 860                 {
 861                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 862                 }
 863
 864                 /* Up to here the process is the same for X.509 certificates and
 865                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 866                  * be easily extended to work with openpgp keys as well.
 867                  */
 868                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 869                 {
 870                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 871                         return;
 872                 }
 873
 874                 ret = gnutls_x509_crt_init(&cert);
 875                 if (ret < 0)
 876                 {
 877                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 878                         return;
 879                 }
 880
 881                 cert_list_size = 0;
 882                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 883                 if (cert_list == NULL)
 884                 {
 885                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 886                         return;
 887                 }
 888
 889                 /* This is not a real world example, since we only check the first
 890                  * certificate in the given chain.
 891                  */
 892
 893                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 894                 if (ret < 0)
 895                 {
 896                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 897                         return;
 898                 }
 899
 900                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 901
 902                 certinfo->data.insert(std::make_pair("dn",name));
 903
 904                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 905
 906                 certinfo->data.insert(std::make_pair("issuer",name));
 907
 908                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 909                 {
 910                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 911                 }
 912                 else
 913                 {
 914                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 915                 }
 916
 917                 /* Beware here we do not check for errors.
 918                  */
 919                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 920                 {
 921                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 922                 }
 923
 924                 gnutls_x509_crt_deinit(cert);
 925
 926                 return;
 927         }
 928
 929         void OnEvent(Event* ev)
 930         {
 931                 GenericCapHandler(ev, "tls", "tls");
 932         }
 933
 934         void Prioritize()
 935         {
 936                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 937                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIO_AFTER, &server);
 938         }
 939 };
 940
 941 MODULE_INIT(ModuleSSLGnuTLS)