src/modules/extra/m_ssl_gnutls.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
   5  *   Copyright (C) 2008 John Brooks <john.brooks@dereferenced.net>
   6  *   Copyright (C) 2006-2008 Craig Edwards <craigedwards@brainbox.cc>
   7  *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
   8  *   Copyright (C) 2006 Oliver Lupton <oliverlupton@gmail.com>
   9  *
  10  * This file is part of InspIRCd.  InspIRCd is free software: you can
  11  * redistribute it and/or modify it under the terms of the GNU General Public
  12  * License as published by the Free Software Foundation, version 2.
  13  *
  14  * This program is distributed in the hope that it will be useful, but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  16  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  17  * details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23
  24 #include "inspircd.h"
  25 #include <gcrypt.h>
  26 #include <gnutls/gnutls.h>
  27 #include <gnutls/x509.h>
  28 #include "modules/ssl.h"
  29 #include "modules/cap.h"
  30
  31 #if ((GNUTLS_VERSION_MAJOR > 2) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 9) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR == 9 && GNUTLS_VERSION_PATCH >= 8))
  32 #define GNUTLS_HAS_MAC_GET_ID
  33 #include <gnutls/crypto.h>
  34 #endif
  35
  36 #ifdef _WIN32
  37 # pragma comment(lib, "libgnutls.lib")
  38 # pragma comment(lib, "libgcrypt.lib")
  39 # pragma comment(lib, "libgpg-error.lib")
  40 # pragma comment(lib, "user32.lib")
  41 # pragma comment(lib, "advapi32.lib")
  42 # pragma comment(lib, "libgcc.lib")
  43 # pragma comment(lib, "libmingwex.lib")
  44 # pragma comment(lib, "gdi32.lib")
  45 #endif
  46
  47 /* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") exec("libgcrypt-config --cflags") */
  48 /* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") exec("libgcrypt-config --libs") */
  49 /* $NoPedantic */
  50
  51 // These don't exist in older GnuTLS versions
  52 #if ((GNUTLS_VERSION_MAJOR > 2) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 1) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR == 1 && GNUTLS_VERSION_MICRO >= 7))
  53 #define GNUTLS_NEW_PRIO_API
  54 #endif
  55
  56 #if(GNUTLS_VERSION_MAJOR < 2)
  57 typedef gnutls_certificate_credentials_t gnutls_certificate_credentials;
  58 typedef gnutls_dh_params_t gnutls_dh_params;
  59 #endif
  60
  61 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  62
  63 static std::vector<gnutls_x509_crt_t> x509_certs;
  64 static gnutls_x509_privkey_t x509_key;
  65 #if(GNUTLS_VERSION_MAJOR < 2 || ( GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR < 12 ) )
  66 static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs,
  67         const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr_st * st) {
  68
  69         st->type = GNUTLS_CRT_X509;
  70 #else
  71 static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs,
  72         const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr2_st * st) {
  73         st->cert_type = GNUTLS_CRT_X509;
  74         st->key_type = GNUTLS_PRIVKEY_X509;
  75 #endif
  76         st->ncerts = x509_certs.size();
  77         st->cert.x509 = &x509_certs[0];
  78         st->key.x509 = x509_key;
  79         st->deinit_all = 0;
  80
  81         return 0;
  82 }
  83
  84 class RandGen : public HandlerBase2<void, char*, size_t>
  85 {
  86  public:
  87         RandGen() {}
  88         void Call(char* buffer, size_t len)
  89         {
  90                 gcry_randomize(buffer, len, GCRY_STRONG_RANDOM);
  91         }
  92 };
  93
  94 /** Represents an SSL user's extra data
  95  */
  96 class issl_session
  97 {
  98 public:
  99         StreamSocket* socket;
 100         gnutls_session_t sess;
 101         issl_status status;
 102         reference<ssl_cert> cert;
 103
 104         issl_session() : socket(NULL), sess(NULL) {}
 105 };
 106
 107 class GnuTLSIOHook : public SSLIOHook
 108 {
 109  private:
 110         void InitSession(StreamSocket* user, bool me_server)
 111         {
 112                 issl_session* session = &sessions[user->GetFd()];
 113
 114                 gnutls_init(&session->sess, me_server ? GNUTLS_SERVER : GNUTLS_CLIENT);
 115                 session->socket = user;
 116
 117                 #ifdef GNUTLS_NEW_PRIO_API
 118                 gnutls_priority_set(session->sess, priority);
 119                 #endif
 120                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 121                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 122                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(session));
 123                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 124                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 125
 126                 if (me_server)
 127                         gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 128
 129                 Handshake(session, user);
 130         }
 131
 132         void CloseSession(issl_session* session)
 133         {
 134                 if (session->sess)
 135                 {
 136                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 137                         gnutls_deinit(session->sess);
 138                 }
 139                 session->socket = NULL;
 140                 session->sess = NULL;
 141                 session->cert = NULL;
 142                 session->status = ISSL_NONE;
 143         }
 144
 145         bool Handshake(issl_session* session, StreamSocket* user)
 146         {
 147                 int ret = gnutls_handshake(session->sess);
 148
 149                 if (ret < 0)
 150                 {
 151                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 152                         {
 153                                 // Handshake needs resuming later, read() or write() would have blocked.
 154
 155                                 if(gnutls_record_get_direction(session->sess) == 0)
 156                                 {
 157                                         // gnutls_handshake() wants to read() again.
 158                                         session->status = ISSL_HANDSHAKING_READ;
 159                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 160                                 }
 161                                 else
 162                                 {
 163                                         // gnutls_handshake() wants to write() again.
 164                                         session->status = ISSL_HANDSHAKING_WRITE;
 165                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 166                                 }
 167                         }
 168                         else
 169                         {
 170                                 user->SetError("Handshake Failed - " + std::string(gnutls_strerror(ret)));
 171                                 CloseSession(session);
 172                                 session->status = ISSL_CLOSING;
 173                         }
 174
 175                         return false;
 176                 }
 177                 else
 178                 {
 179                         // Change the seesion state
 180                         session->status = ISSL_HANDSHAKEN;
 181
 182                         VerifyCertificate(session,user);
 183
 184                         // Finish writing, if any left
 185                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 186
 187                         return true;
 188                 }
 189         }
 190
 191         void VerifyCertificate(issl_session* session, StreamSocket* user)
 192         {
 193                 if (!session->sess || !user)
 194                         return;
 195
 196                 unsigned int status;
 197                 const gnutls_datum_t* cert_list;
 198                 int ret;
 199                 unsigned int cert_list_size;
 200                 gnutls_x509_crt_t cert;
 201                 char str[512];
 202                 unsigned char digest[512];
 203                 size_t digest_size = sizeof(digest);
 204                 size_t name_size = sizeof(str);
 205                 ssl_cert* certinfo = new ssl_cert;
 206                 session->cert = certinfo;
 207
 208                 /* This verification function uses the trusted CAs in the credentials
 209                  * structure. So you must have installed one or more CA certificates.
 210                  */
 211                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 212
 213                 if (ret < 0)
 214                 {
 215                         certinfo->error = std::string(gnutls_strerror(ret));
 216                         return;
 217                 }
 218
 219                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 220                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 221                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 222                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 223
 224                 /* Up to here the process is the same for X.509 certificates and
 225                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 226                  * be easily extended to work with openpgp keys as well.
 227                  */
 228                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 229                 {
 230                         certinfo->error = "No X509 keys sent";
 231                         return;
 232                 }
 233
 234                 ret = gnutls_x509_crt_init(&cert);
 235                 if (ret < 0)
 236                 {
 237                         certinfo->error = gnutls_strerror(ret);
 238                         return;
 239                 }
 240
 241                 cert_list_size = 0;
 242                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 243                 if (cert_list == NULL)
 244                 {
 245                         certinfo->error = "No certificate was found";
 246                         goto info_done_dealloc;
 247                 }
 248
 249                 /* This is not a real world example, since we only check the first
 250                  * certificate in the given chain.
 251                  */
 252
 253                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 254                 if (ret < 0)
 255                 {
 256                         certinfo->error = gnutls_strerror(ret);
 257                         goto info_done_dealloc;
 258                 }
 259
 260                 gnutls_x509_crt_get_dn(cert, str, &name_size);
 261                 certinfo->dn = str;
 262
 263                 gnutls_x509_crt_get_issuer_dn(cert, str, &name_size);
 264                 certinfo->issuer = str;
 265
 266                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, hash, digest, &digest_size)) < 0)
 267                 {
 268                         certinfo->error = gnutls_strerror(ret);
 269                 }
 270                 else
 271                 {
 272                         certinfo->fingerprint = BinToHex(digest, digest_size);
 273                 }
 274
 275                 /* Beware here we do not check for errors.
 276                  */
 277                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 278                 {
 279                         certinfo->error = "Not activated, or expired certificate";
 280                 }
 281
 282 info_done_dealloc:
 283                 gnutls_x509_crt_deinit(cert);
 284         }
 285
 286         static const char* UnknownIfNULL(const char* str)
 287         {
 288                 return str ? str : "UNKNOWN";
 289         }
 290
 291         static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t session_wrap, void* buffer, size_t size)
 292         {
 293                 issl_session* session = reinterpret_cast<issl_session*>(session_wrap);
 294                 if (session->socket->GetEventMask() & FD_READ_WILL_BLOCK)
 295                 {
 296 #ifdef _WIN32
 297                         gnutls_transport_set_errno(session->sess, EAGAIN);
 298 #else
 299                         errno = EAGAIN;
 300 #endif
 301                         return -1;
 302                 }
 303
 304                 int rv = ServerInstance->SE->Recv(session->socket, reinterpret_cast<char *>(buffer), size, 0);
 305
 306 #ifdef _WIN32
 307                 if (rv < 0)
 308                 {
 309                         /* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
 310                          * and then set errno appropriately.
 311                          * The gnutls library may also have a different errno variable than us, see
 312                          * gnutls_transport_set_errno(3).
 313                          */
 314                         gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
 315                 }
 316 #endif
 317
 318                 if (rv < (int)size)
 319                         ServerInstance->SE->ChangeEventMask(session->socket, FD_READ_WILL_BLOCK);
 320                 return rv;
 321         }
 322
 323         static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t session_wrap, const void* buffer, size_t size)
 324         {
 325                 issl_session* session = reinterpret_cast<issl_session*>(session_wrap);
 326                 if (session->socket->GetEventMask() & FD_WRITE_WILL_BLOCK)
 327                 {
 328 #ifdef _WIN32
 329                         gnutls_transport_set_errno(session->sess, EAGAIN);
 330 #else
 331                         errno = EAGAIN;
 332 #endif
 333                         return -1;
 334                 }
 335
 336                 int rv = ServerInstance->SE->Send(session->socket, reinterpret_cast<const char *>(buffer), size, 0);
 337
 338 #ifdef _WIN32
 339                 if (rv < 0)
 340                 {
 341                         /* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
 342                          * and then set errno appropriately.
 343                          * The gnutls library may also have a different errno variable than us, see
 344                          * gnutls_transport_set_errno(3).
 345                          */
 346                         gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
 347                 }
 348 #endif
 349
 350                 if (rv < (int)size)
 351                         ServerInstance->SE->ChangeEventMask(session->socket, FD_WRITE_WILL_BLOCK);
 352                 return rv;
 353         }
 354
 355  public:
 356         issl_session* sessions;
 357         gnutls_certificate_credentials_t x509_cred;
 358
 359         gnutls_digest_algorithm_t hash;
 360         #ifdef GNUTLS_NEW_PRIO_API
 361         gnutls_priority_t priority;
 362         #endif
 363         int dh_bits;
 364
 365         GnuTLSIOHook(Module* parent)
 366                 : SSLIOHook(parent, "ssl/gnutls")
 367         {
 368                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 369         }
 370
 371         ~GnuTLSIOHook()
 372         {
 373                 delete[] sessions;
 374         }
 375
 376         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE
 377         {
 378                 issl_session* session = &sessions[user->GetFd()];
 379
 380                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 381                 if (session->sess)
 382                         return;
 383
 384                 InitSession(user, true);
 385         }
 386
 387         void OnStreamSocketConnect(StreamSocket* user) CXX11_OVERRIDE
 388         {
 389                 InitSession(user, false);
 390         }
 391
 392         void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE
 393         {
 394                 CloseSession(&sessions[user->GetFd()]);
 395         }
 396
 397         int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE
 398         {
 399                 issl_session* session = &sessions[user->GetFd()];
 400
 401                 if (!session->sess)
 402                 {
 403                         CloseSession(session);
 404                         user->SetError("No SSL session");
 405                         return -1;
 406                 }
 407
 408                 if (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE)
 409                 {
 410                         // The handshake isn't finished, try to finish it.
 411
 412                         if(!Handshake(session, user))
 413                         {
 414                                 if (session->status != ISSL_CLOSING)
 415                                         return 0;
 416                                 return -1;
 417                         }
 418                 }
 419
 420                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 421
 422                 if (session->status == ISSL_HANDSHAKEN)
 423                 {
 424                         char* buffer = ServerInstance->GetReadBuffer();
 425                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 426                         int ret = gnutls_record_recv(session->sess, buffer, bufsiz);
 427                         if (ret > 0)
 428                         {
 429                                 recvq.append(buffer, ret);
 430                                 return 1;
 431                         }
 432                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 433                         {
 434                                 return 0;
 435                         }
 436                         else if (ret == 0)
 437                         {
 438                                 user->SetError("Connection closed");
 439                                 CloseSession(session);
 440                                 return -1;
 441                         }
 442                         else
 443                         {
 444                                 user->SetError(gnutls_strerror(ret));
 445                                 CloseSession(session);
 446                                 return -1;
 447                         }
 448                 }
 449                 else if (session->status == ISSL_CLOSING)
 450                         return -1;
 451
 452                 return 0;
 453         }
 454
 455         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq) CXX11_OVERRIDE
 456         {
 457                 issl_session* session = &sessions[user->GetFd()];
 458
 459                 if (!session->sess)
 460                 {
 461                         CloseSession(session);
 462                         user->SetError("No SSL session");
 463                         return -1;
 464                 }
 465
 466                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 467                 {
 468                         // The handshake isn't finished, try to finish it.
 469                         Handshake(session, user);
 470                         if (session->status != ISSL_CLOSING)
 471                                 return 0;
 472                         return -1;
 473                 }
 474
 475                 int ret = 0;
 476
 477                 if (session->status == ISSL_HANDSHAKEN)
 478                 {
 479                         ret = gnutls_record_send(session->sess, sendq.data(), sendq.length());
 480
 481                         if (ret == (int)sendq.length())
 482                         {
 483                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE);
 484                                 return 1;
 485                         }
 486                         else if (ret > 0)
 487                         {
 488                                 sendq = sendq.substr(ret);
 489                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 490                                 return 0;
 491                         }
 492                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED || ret == 0)
 493                         {
 494                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 495                                 return 0;
 496                         }
 497                         else // (ret < 0)
 498                         {
 499                                 user->SetError(gnutls_strerror(ret));
 500                                 CloseSession(session);
 501                                 return -1;
 502                         }
 503                 }
 504
 505                 return 0;
 506         }
 507
 508         ssl_cert* GetCertificate(StreamSocket* sock) CXX11_OVERRIDE
 509         {
 510                 int fd = sock->GetFd();
 511                 issl_session* session = &sessions[fd];
 512                 return session->cert;
 513         }
 514
 515         void TellCiphersAndFingerprint(LocalUser* user)
 516         {
 517                 const gnutls_session_t& sess = sessions[user->eh.GetFd()].sess;
 518                 if (sess)
 519                 {
 520                         std::string text = "*** You are connected using SSL cipher '";
 521
 522                         text += UnknownIfNULL(gnutls_kx_get_name(gnutls_kx_get(sess)));
 523                         text.append("-").append(UnknownIfNULL(gnutls_cipher_get_name(gnutls_cipher_get(sess)))).append("-");
 524                         text.append(UnknownIfNULL(gnutls_mac_get_name(gnutls_mac_get(sess)))).append("'");
 525
 526                         ssl_cert* cert = sessions[user->eh.GetFd()].cert;
 527                         if (!cert->fingerprint.empty())
 528                                 text += " and your SSL fingerprint is " + cert->fingerprint;
 529
 530                         user->WriteNotice(text);
 531                 }
 532         }
 533 };
 534
 535 class CommandStartTLS : public SplitCommand
 536 {
 537         IOHook& hook;
 538
 539  public:
 540         bool enabled;
 541         CommandStartTLS(Module* mod, IOHook& Hook)
 542                 : SplitCommand(mod, "STARTTLS")
 543                 , hook(Hook)
 544         {
 545                 enabled = true;
 546                 works_before_reg = true;
 547         }
 548
 549         CmdResult HandleLocal(const std::vector<std::string> &parameters, LocalUser *user)
 550         {
 551                 if (!enabled)
 552                 {
 553                         user->WriteNumeric(691, "%s :STARTTLS is not enabled", user->nick.c_str());
 554                         return CMD_FAILURE;
 555                 }
 556
 557                 if (user->registered == REG_ALL)
 558                 {
 559                         user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration is complete", user->nick.c_str());
 560                 }
 561                 else
 562                 {
 563                         if (!user->eh.GetIOHook())
 564                         {
 565                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
 566                                 /* We need to flush the write buffer prior to adding the IOHook,
 567                                  * otherwise we'll be sending this line inside the SSL session - which
 568                                  * won't start its handshake until the client gets this line. Currently,
 569                                  * we assume the write will not block here; this is usually safe, as
 570                                  * STARTTLS is sent very early on in the registration phase, where the
 571                                  * user hasn't built up much sendq. Handling a blocked write here would
 572                                  * be very annoying.
 573                                  */
 574                                 user->eh.DoWrite();
 575                                 user->eh.AddIOHook(&hook);
 576                                 hook.OnStreamSocketAccept(&user->eh, NULL, NULL);
 577                         }
 578                         else
 579                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
 580                 }
 581
 582                 return CMD_FAILURE;
 583         }
 584 };
 585
 586 class ModuleSSLGnuTLS : public Module
 587 {
 588         GnuTLSIOHook iohook;
 589
 590         gnutls_dh_params_t dh_params;
 591
 592         std::string sslports;
 593
 594         bool cred_alloc;
 595         bool dh_alloc;
 596
 597         RandGen randhandler;
 598         CommandStartTLS starttls;
 599
 600         GenericCap capHandler;
 601
 602  public:
 603         ModuleSSLGnuTLS()
 604                 : iohook(this), starttls(this, iohook), capHandler(this, "tls")
 605         {
 606                 gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
 607
 608                 gnutls_global_init(); // This must be called once in the program
 609                 gnutls_x509_privkey_init(&x509_key);
 610
 611                 #ifdef GNUTLS_NEW_PRIO_API
 612                 // Init this here so it's always initialized, avoids an extra boolean
 613                 gnutls_priority_init(&iohook.priority, "NORMAL", NULL);
 614                 #endif
 615
 616                 cred_alloc = false;
 617                 dh_alloc = false;
 618         }
 619
 620         void init() CXX11_OVERRIDE
 621         {
 622                 // Needs the flag as it ignores a plain /rehash
 623                 OnModuleRehash(NULL,"ssl");
 624
 625                 ServerInstance->GenRandom = &randhandler;
 626
 627                 // Void return, guess we assume success
 628                 gnutls_certificate_set_dh_params(iohook.x509_cred, dh_params);
 629
 630                 ServerInstance->Modules->AddService(iohook);
 631                 ServerInstance->Modules->AddService(starttls);
 632         }
 633
 634         void OnRehash(User* user) CXX11_OVERRIDE
 635         {
 636                 sslports.clear();
 637
 638                 ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
 639                 starttls.enabled = Conf->getBool("starttls", true);
 640
 641                 if (Conf->getBool("showports", true))
 642                 {
 643                         sslports = Conf->getString("advertisedports");
 644                         if (!sslports.empty())
 645                                 return;
 646
 647                         for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 648                         {
 649                                 ListenSocket* port = ServerInstance->ports[i];
 650                                 if (port->bind_tag->getString("ssl") != "gnutls")
 651                                         continue;
 652
 653                                 const std::string& portid = port->bind_desc;
 654                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Enabling SSL for port %s", portid.c_str());
 655
 656                                 if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
 657                                 {
 658                                         /*
 659                                          * Found an SSL port for clients that is not bound to 127.0.0.1 and handled by us, display
 660                                          * the IP:port in ISUPPORT.
 661                                          *
 662                                          * We used to advertise all ports seperated by a ';' char that matched the above criteria,
 663                                          * but this resulted in too long ISUPPORT lines if there were lots of ports to be displayed.
 664                                          * To solve this by default we now only display the first IP:port found and let the user
 665                                          * configure the exact value for the 005 token, if necessary.
 666                                          */
 667                                         sslports = portid;
 668                                         break;
 669                                 }
 670                         }
 671                 }
 672         }
 673
 674         void OnModuleRehash(User* user, const std::string &param) CXX11_OVERRIDE
 675         {
 676                 if(param != "ssl")
 677                         return;
 678
 679                 std::string keyfile;
 680                 std::string certfile;
 681                 std::string cafile;
 682                 std::string crlfile;
 683                 OnRehash(user);
 684
 685                 ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
 686
 687                 cafile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("cafile", "ca.pem"));
 688                 crlfile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("crlfile", "crl.pem"));
 689                 certfile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("certfile", "cert.pem"));
 690                 keyfile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("keyfile", "key.pem"));
 691                 int dh_bits = Conf->getInt("dhbits");
 692                 std::string hashname = Conf->getString("hash", "md5");
 693
 694                 // The GnuTLS manual states that the gnutls_set_default_priority()
 695                 // call we used previously when initializing the session is the same
 696                 // as setting the "NORMAL" priority string.
 697                 // Thus if the setting below is not in the config we will behave exactly
 698                 // the same as before, when the priority setting wasn't available.
 699                 std::string priorities = Conf->getString("priority", "NORMAL");
 700
 701                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 702                         dh_bits = 1024;
 703
 704                 iohook.dh_bits = dh_bits;
 705
 706                 // As older versions of gnutls can't do this, let's disable it where needed.
 707 #ifdef GNUTLS_HAS_MAC_GET_ID
 708                 // As gnutls_digest_algorithm_t and gnutls_mac_algorithm_t are mapped 1:1, we can do this
 709                 // There is no gnutls_dig_get_id() at the moment, but it may come later
 710                 iohook.hash = (gnutls_digest_algorithm_t)gnutls_mac_get_id(hashname.c_str());
 711                 if (iohook.hash == GNUTLS_DIG_UNKNOWN)
 712                         throw ModuleException("Unknown hash type " + hashname);
 713
 714                 // Check if the user is walking around with their head in the ass,
 715                 // giving us something that is a valid MAC but not digest
 716                 gnutls_hash_hd_t is_digest;
 717                 if (gnutls_hash_init(&is_digest, iohook.hash) < 0)
 718                         throw ModuleException("Unknown hash type " + hashname);
 719                 gnutls_hash_deinit(is_digest, NULL);
 720 #else
 721                 if (hashname == "md5")
 722                         iohook.hash = GNUTLS_DIG_MD5;
 723                 else if (hashname == "sha1")
 724                         iohook.hash = GNUTLS_DIG_SHA1;
 725                 else
 726                         throw ModuleException("Unknown hash type " + hashname);
 727 #endif
 728
 729                 int ret;
 730
 731                 if (dh_alloc)
 732                 {
 733                         gnutls_dh_params_deinit(dh_params);
 734                         dh_alloc = false;
 735                         dh_params = NULL;
 736                 }
 737
 738                 if (cred_alloc)
 739                 {
 740                         // Deallocate the old credentials
 741                         gnutls_certificate_free_credentials(iohook.x509_cred);
 742
 743                         for(unsigned int i=0; i < x509_certs.size(); i++)
 744                                 gnutls_x509_crt_deinit(x509_certs[i]);
 745                         x509_certs.clear();
 746                 }
 747
 748                 ret = gnutls_certificate_allocate_credentials(&iohook.x509_cred);
 749                 cred_alloc = (ret >= 0);
 750                 if (!cred_alloc)
 751                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 752
 753                 if((ret =gnutls_certificate_set_x509_trust_file(iohook.x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 754                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));
 755
 756                 if((ret = gnutls_certificate_set_x509_crl_file (iohook.x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 757                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));
 758
 759                 FileReader reader;
 760
 761                 reader.Load(certfile);
 762                 std::string cert_string = reader.GetString();
 763                 gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), static_cast<unsigned int>(cert_string.length()) };
 764
 765                 reader.Load(keyfile);
 766                 std::string key_string = reader.GetString();
 767                 gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), static_cast<unsigned int>(key_string.length()) };
 768
 769                 // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 770                 unsigned int certcount = 3;
 771                 x509_certs.resize(certcount);
 772                 ret = gnutls_x509_crt_list_import(&x509_certs[0], &certcount, &cert_datum, GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
 773                 if (ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
 774                 {
 775                         // the buffer wasn't big enough to hold all certs but gnutls updated certcount to the number of available certs, try again with a bigger buffer
 776                         x509_certs.resize(certcount);
 777                         ret = gnutls_x509_crt_list_import(&x509_certs[0], &certcount, &cert_datum, GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
 778                 }
 779
 780                 if (ret <= 0)
 781                 {
 782                         // clear the vector so we won't call gnutls_x509_crt_deinit() on the (uninited) certs later
 783                         x509_certs.clear();
 784                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + ((ret < 0) ? (std::string(gnutls_strerror(ret))) : "No certs could be read"));
 785                 }
 786                 x509_certs.resize(ret);
 787
 788                 if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0)
 789                         throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret)));
 790
 791                 if((ret = gnutls_certificate_set_x509_key(iohook.x509_cred, &x509_certs[0], certcount, x509_key)) < 0)
 792                         throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
 793
 794                 #ifdef GNUTLS_NEW_PRIO_API
 795                 // It's safe to call this every time as we cannot have this uninitialized, see constructor and below.
 796                 gnutls_priority_deinit(iohook.priority);
 797
 798                 // Try to set the priorities for ciphers, kex methods etc. to the user supplied string
 799                 // If the user did not supply anything then the string is already set to "NORMAL"
 800                 const char* priocstr = priorities.c_str();
 801                 const char* prioerror;
 802
 803                 if ((ret = gnutls_priority_init(&iohook.priority, priocstr, &prioerror)) < 0)
 804                 {
 805                         // gnutls did not understand the user supplied string, log and fall back to the default priorities
 806                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Failed to set priorities to \"%s\": %s Syntax error at position %u, falling back to default (NORMAL)", priorities.c_str(), gnutls_strerror(ret), (unsigned int) (prioerror - priocstr));
 807                         gnutls_priority_init(&iohook.priority, "NORMAL", NULL);
 808                 }
 809
 810                 #else
 811                 if (priorities != "NORMAL")
 812                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "You've set <gnutls:priority> to a value other than the default, but this is only supported with GnuTLS v2.1.7 or newer. Your GnuTLS version is older than that so the option will have no effect.");
 813                 #endif
 814
 815                 #if(GNUTLS_VERSION_MAJOR < 2 || ( GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR < 12 ) )
 816                 gnutls_certificate_client_set_retrieve_function (iohook.x509_cred, cert_callback);
 817                 #else
 818                 gnutls_certificate_set_retrieve_function (iohook.x509_cred, cert_callback);
 819                 #endif
 820                 ret = gnutls_dh_params_init(&dh_params);
 821                 dh_alloc = (ret >= 0);
 822                 if (!dh_alloc)
 823                 {
 824                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 825                         return;
 826                 }
 827
 828                 std::string dhfile = Conf->getString("dhfile");
 829                 if (!dhfile.empty())
 830                 {
 831                         // Try to load DH params from file
 832                         reader.Load(dhfile);
 833                         std::string dhstring = reader.GetString();
 834                         gnutls_datum_t dh_datum = { (unsigned char*)dhstring.data(), static_cast<unsigned int>(dhstring.length()) };
 835
 836                         if ((ret = gnutls_dh_params_import_pkcs3(dh_params, &dh_datum, GNUTLS_X509_FMT_PEM)) < 0)
 837                         {
 838                                 // File unreadable or GnuTLS was unhappy with the contents, generate the DH primes now
 839                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Generating DH parameters because I failed to load them from file '%s': %s", dhfile.c_str(), gnutls_strerror(ret));
 840                                 GenerateDHParams();
 841                         }
 842                 }
 843                 else
 844                 {
 845                         GenerateDHParams();
 846                 }
 847         }
 848
 849         void GenerateDHParams()
 850         {
 851                 // Generate Diffie Hellman parameters - for use with DHE
 852                 // kx algorithms. These should be discarded and regenerated
 853                 // once a day, once a week or once a month. Depending on the
 854                 // security requirements.
 855
 856                 if (!dh_alloc)
 857                         return;
 858
 859                 int ret;
 860
 861                 if((ret = gnutls_dh_params_generate2(dh_params, iohook.dh_bits)) < 0)
 862                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Failed to generate DH parameters (%d bits): %s", iohook.dh_bits, gnutls_strerror(ret));
 863         }
 864
 865         ~ModuleSSLGnuTLS()
 866         {
 867                 for(unsigned int i=0; i < x509_certs.size(); i++)
 868                         gnutls_x509_crt_deinit(x509_certs[i]);
 869
 870                 gnutls_x509_privkey_deinit(x509_key);
 871                 #ifdef GNUTLS_NEW_PRIO_API
 872                 gnutls_priority_deinit(iohook.priority);
 873                 #endif
 874
 875                 if (dh_alloc)
 876                         gnutls_dh_params_deinit(dh_params);
 877                 if (cred_alloc)
 878                         gnutls_certificate_free_credentials(iohook.x509_cred);
 879
 880                 gnutls_global_deinit();
 881                 ServerInstance->GenRandom = &ServerInstance->HandleGenRandom;
 882         }
 883
 884         void OnCleanup(int target_type, void* item) CXX11_OVERRIDE
 885         {
 886                 if(target_type == TYPE_USER)
 887                 {
 888                         LocalUser* user = IS_LOCAL(static_cast<User*>(item));
 889
 890                         if (user && user->eh.GetIOHook() == &iohook)
 891                         {
 892                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 893                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 894                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 895                         }
 896                 }
 897         }
 898
 899         Version GetVersion() CXX11_OVERRIDE
 900         {
 901                 return Version("Provides SSL support for clients", VF_VENDOR);
 902         }
 903
 904         void On005Numeric(std::map<std::string, std::string>& tokens) CXX11_OVERRIDE
 905         {
 906                 if (!sslports.empty())
 907                         tokens["SSL"] = sslports;
 908                 if (starttls.enabled)
 909                         tokens["STARTTLS"];
 910         }
 911
 912         void OnHookIO(StreamSocket* user, ListenSocket* lsb) CXX11_OVERRIDE
 913         {
 914                 if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "gnutls")
 915                 {
 916                         /* Hook the user with our module */
 917                         user->AddIOHook(&iohook);
 918                 }
 919         }
 920
 921         void OnUserConnect(LocalUser* user) CXX11_OVERRIDE
 922         {
 923                 if (user->eh.GetIOHook() == &iohook)
 924                         iohook.TellCiphersAndFingerprint(user);
 925         }
 926
 927         void OnEvent(Event& ev) CXX11_OVERRIDE
 928         {
 929                 if (starttls.enabled)
 930                         capHandler.HandleEvent(ev);
 931         }
 932 };
 933
 934 MODULE_INIT(ModuleSSLGnuTLS)