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         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: " + 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->io == 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->io = NULL;
 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->io && isin(targetip,user->GetPort(),listenports))
 350                 {
 351                         /* Hook the user with our module */
 352                         user->io = 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                                         readresult = 0;
 542                                         CloseSession(session);
 543                                 }
 544                         }
 545                         else
 546                         {
 547                                 // Read successfully 'ret' bytes into inbuf + inbufoffset
 548                                 // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
 549                                 // 'buffer' is 'count' long
 550
 551                                 unsigned int length = ret + session->inbufoffset;
 552
 553                                 if(count <= length)
 554                                 {
 555                                         memcpy(buffer, session->inbuf, count);
 556                                         // Move the stuff left in inbuf to the beginning of it
 557                                         memmove(session->inbuf, session->inbuf + count, (length - count));
 558                                         // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
 559                                         session->inbufoffset = length - count;
 560                                         // Insp uses readresult as the count of how much data there is in buffer, so:
 561                                         readresult = count;
 562                                 }
 563                                 else
 564                                 {
 565                                         // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
 566                                         memcpy(buffer, session->inbuf, length);
 567                                         // Zero the offset, as there's nothing there..
 568                                         session->inbufoffset = 0;
 569                                         // As above
 570                                         readresult = length;
 571                                 }
 572                         }
 573                 }
 574                 else if(session->status == ISSL_CLOSING)
 575                         readresult = 0;
 576
 577                 return 1;
 578         }
 579
 580         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 581         {
 582                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 583                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 584                         return 0;
 585
 586                 issl_session* session = &sessions[fd];
 587                 const char* sendbuffer = buffer;
 588
 589                 if (!session->sess)
 590                 {
 591                         CloseSession(session);
 592                         return 1;
 593                 }
 594
 595                 session->outbuf.append(sendbuffer, count);
 596                 sendbuffer = session->outbuf.c_str();
 597                 count = session->outbuf.size();
 598
 599                 if (session->status == ISSL_HANDSHAKING_WRITE)
 600                 {
 601                         // The handshake isn't finished, try to finish it.
 602                         Handshake(session);
 603                         errno = EAGAIN;
 604                         return -1;
 605                 }
 606
 607                 int ret = 0;
 608
 609                 if (session->status == ISSL_HANDSHAKEN)
 610                 {
 611                         ret = gnutls_record_send(session->sess, sendbuffer, count);
 612
 613                         if (ret == 0)
 614                         {
 615                                 CloseSession(session);
 616                         }
 617                         else if (ret < 0)
 618                         {
 619                                 if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
 620                                 {
 621                                         CloseSession(session);
 622                                 }
 623                                 else
 624                                 {
 625                                         errno = EAGAIN;
 626                                 }
 627                         }
 628                         else
 629                         {
 630                                 session->outbuf = session->outbuf.substr(ret);
 631                         }
 632                 }
 633
 634                 MakePollWrite(session);
 635
 636                 /* Who's smart idea was it to return 1 when we havent written anything?
 637                  * This fucks the buffer up in BufferedSocket :p
 638                  */
 639                 return ret < 1 ? 0 : ret;
 640         }
 641
 642         // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
 643         virtual void OnWhois(User* source, User* dest)
 644         {
 645                 if (!clientactive)
 646                         return;
 647
 648                 // Bugfix, only send this numeric for *our* SSL users
 649                 if (dest->GetExt("ssl", dummy) || ((IS_LOCAL(dest) && (dest->io == this))))
 650                 {
 651                         ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick.c_str(), dest->nick.c_str());
 652                 }
 653         }
 654
 655         virtual void OnSyncUserMetaData(User* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
 656         {
 657                 // check if the linking module wants to know about OUR metadata
 658                 if(extname == "ssl")
 659                 {
 660                         // check if this user has an swhois field to send
 661                         if(user->GetExt(extname, dummy))
 662                         {
 663                                 // call this function in the linking module, let it format the data how it
 664                                 // sees fit, and send it on its way. We dont need or want to know how.
 665                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
 666                         }
 667                 }
 668         }
 669
 670         virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
 671         {
 672                 // check if its our metadata key, and its associated with a user
 673                 if ((target_type == TYPE_USER) && (extname == "ssl"))
 674                 {
 675                         User* dest = (User*)target;
 676                         // if they dont already have an ssl flag, accept the remote server's
 677                         if (!dest->GetExt(extname, dummy))
 678                         {
 679                                 dest->Extend(extname, "ON");
 680                         }
 681                 }
 682         }
 683
 684         bool Handshake(issl_session* session)
 685         {
 686                 int ret = gnutls_handshake(session->sess);
 687
 688                 if (ret < 0)
 689                 {
 690                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 691                         {
 692                                 // Handshake needs resuming later, read() or write() would have blocked.
 693
 694                                 if(gnutls_record_get_direction(session->sess) == 0)
 695                                 {
 696                                         // gnutls_handshake() wants to read() again.
 697                                         session->status = ISSL_HANDSHAKING_READ;
 698                                 }
 699                                 else
 700                                 {
 701                                         // gnutls_handshake() wants to write() again.
 702                                         session->status = ISSL_HANDSHAKING_WRITE;
 703                                         MakePollWrite(session);
 704                                 }
 705                         }
 706                         else
 707                         {
 708                                 // Handshake failed.
 709                                 CloseSession(session);
 710                                 session->status = ISSL_CLOSING;
 711                         }
 712
 713                         return false;
 714                 }
 715                 else
 716                 {
 717                         // Handshake complete.
 718                         // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
 719                         User* extendme = ServerInstance->FindDescriptor(session->fd);
 720                         if (extendme)
 721                         {
 722                                 if (!extendme->GetExt("ssl", dummy))
 723                                         extendme->Extend("ssl", "ON");
 724                         }
 725
 726                         // Change the seesion state
 727                         session->status = ISSL_HANDSHAKEN;
 728
 729                         // Finish writing, if any left
 730                         MakePollWrite(session);
 731
 732                         return true;
 733                 }
 734         }
 735
 736         virtual void OnPostConnect(User* user)
 737         {
 738                 // This occurs AFTER OnUserConnect so we can be sure the
 739                 // protocol module has propagated the NICK message.
 740                 if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
 741                 {
 742                         // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
 743                         ServerInstance->PI->SendMetaData(user, TYPE_USER, "SSL", "on");
 744
 745                         VerifyCertificate(&sessions[user->GetFd()],user);
 746                         if (sessions[user->GetFd()].sess)
 747                         {
 748                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 749                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 750                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 751                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 752                         }
 753                 }
 754         }
 755
 756         void MakePollWrite(issl_session* session)
 757         {
 758                 //OnRawSocketWrite(session->fd, NULL, 0);
 759                 EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
 760                 if (eh)
 761                         ServerInstance->SE->WantWrite(eh);
 762         }
 763
 764         virtual void OnBufferFlushed(User* user)
 765         {
 766                 if (user->GetExt("ssl"))
 767                 {
 768                         issl_session* session = &sessions[user->GetFd()];
 769                         if (session && session->outbuf.size())
 770                                 OnRawSocketWrite(user->GetFd(), NULL, 0);
 771                 }
 772         }
 773
 774         void CloseSession(issl_session* session)
 775         {
 776                 if(session->sess)
 777                 {
 778                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 779                         gnutls_deinit(session->sess);
 780                 }
 781
 782                 if(session->inbuf)
 783                 {
 784                         delete[] session->inbuf;
 785                 }
 786
 787                 session->outbuf.clear();
 788                 session->inbuf = NULL;
 789                 session->sess = NULL;
 790                 session->status = ISSL_NONE;
 791         }
 792
 793         void VerifyCertificate(issl_session* session, Extensible* user)
 794         {
 795                 if (!session->sess || !user)
 796                         return;
 797
 798                 unsigned int status;
 799                 const gnutls_datum_t* cert_list;
 800                 int ret;
 801                 unsigned int cert_list_size;
 802                 gnutls_x509_crt_t cert;
 803                 char name[MAXBUF];
 804                 unsigned char digest[MAXBUF];
 805                 size_t digest_size = sizeof(digest);
 806                 size_t name_size = sizeof(name);
 807                 ssl_cert* certinfo = new ssl_cert;
 808
 809                 user->Extend("ssl_cert",certinfo);
 810
 811                 /* This verification function uses the trusted CAs in the credentials
 812                  * structure. So you must have installed one or more CA certificates.
 813                  */
 814                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 815
 816                 if (ret < 0)
 817                 {
 818                         certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
 819                         return;
 820                 }
 821
 822                 if (status & GNUTLS_CERT_INVALID)
 823                 {
 824                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
 825                 }
 826                 else
 827                 {
 828                         certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
 829                 }
 830                 if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 831                 {
 832                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
 833                 }
 834                 else
 835                 {
 836                         certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
 837                 }
 838                 if (status & GNUTLS_CERT_REVOKED)
 839                 {
 840                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
 841                 }
 842                 else
 843                 {
 844                         certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
 845                 }
 846                 if (status & GNUTLS_CERT_SIGNER_NOT_CA)
 847                 {
 848                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
 849                 }
 850                 else
 851                 {
 852                         certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
 853                 }
 854
 855                 /* Up to here the process is the same for X.509 certificates and
 856                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 857                  * be easily extended to work with openpgp keys as well.
 858                  */
 859                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 860                 {
 861                         certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
 862                         return;
 863                 }
 864
 865                 ret = gnutls_x509_crt_init(&cert);
 866                 if (ret < 0)
 867                 {
 868                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 869                         return;
 870                 }
 871
 872                 cert_list_size = 0;
 873                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 874                 if (cert_list == NULL)
 875                 {
 876                         certinfo->data.insert(std::make_pair("error","No certificate was found"));
 877                         return;
 878                 }
 879
 880                 /* This is not a real world example, since we only check the first
 881                  * certificate in the given chain.
 882                  */
 883
 884                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 885                 if (ret < 0)
 886                 {
 887                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 888                         return;
 889                 }
 890
 891                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 892
 893                 certinfo->data.insert(std::make_pair("dn",name));
 894
 895                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 896
 897                 certinfo->data.insert(std::make_pair("issuer",name));
 898
 899                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 900                 {
 901                         certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
 902                 }
 903                 else
 904                 {
 905                         certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
 906                 }
 907
 908                 /* Beware here we do not check for errors.
 909                  */
 910                 if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
 911                 {
 912                         certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
 913                 }
 914
 915                 gnutls_x509_crt_deinit(cert);
 916
 917                 return;
 918         }
 919
 920         void OnEvent(Event* ev)
 921         {
 922                 GenericCapHandler(ev, "tls", "tls");
 923                 if (ev->GetEventID() == "cap_req")
 924                 {
 925                         /* GenericCapHandler() Extends("tls") a user if it does
 926                          * CAP REQ tls. Check if this was done.
 927                          */
 928                         CapData *data = (CapData *) ev->GetData();
 929                         if (data->user->Shrink("tls"))
 930                         {
 931                                 /* Not in our spec?!?! */
 932                                 data->user->io = this;
 933                                 OnRawSocketAccept(data->user->GetFd(), data->user->GetIPString(),
 934                                                 data->user->GetPort());
 935                         }
 936                 }
 937         }
 938
 939         void Prioritize()
 940         {
 941                 Module* server = ServerInstance->Modules->Find("m_spanningtree.so");
 942                 ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIO_AFTER, &server);
 943         }
 944 };
 945
 946 MODULE_INIT(ModuleSSLGnuTLS)