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 <gnutls/gnutls.h>
  26 #include <gnutls/x509.h>
  27 #include "modules/ssl.h"
  28 #include "modules/cap.h"
  29
  30 #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))
  31 #define GNUTLS_HAS_MAC_GET_ID
  32 #include <gnutls/crypto.h>
  33 #endif
  34
  35 #if (GNUTLS_VERSION_MAJOR > 2 || GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 12)
  36 # define GNUTLS_HAS_RND
  37 #else
  38 # include <gcrypt.h>
  39 #endif
  40
  41 #ifdef _WIN32
  42 # pragma comment(lib, "libgnutls.lib")
  43 # pragma comment(lib, "libgcrypt.lib")
  44 # pragma comment(lib, "libgpg-error.lib")
  45 # pragma comment(lib, "user32.lib")
  46 # pragma comment(lib, "advapi32.lib")
  47 # pragma comment(lib, "libgcc.lib")
  48 # pragma comment(lib, "libmingwex.lib")
  49 # pragma comment(lib, "gdi32.lib")
  50 #endif
  51
  52 /* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") eval("print `libgcrypt-config --cflags | tr -d \r` if `pkg-config --modversion gnutls 2>/dev/null | tr -d \r` lt '2.12'") -Wno-pedantic */
  53 /* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") eval("print `libgcrypt-config --libs | tr -d \r` if `pkg-config --modversion gnutls 2>/dev/null | tr -d \r` lt '2.12'") */
  54
  55 #ifndef GNUTLS_VERSION_MAJOR
  56 #define GNUTLS_VERSION_MAJOR LIBGNUTLS_VERSION_MAJOR
  57 #define GNUTLS_VERSION_MINOR LIBGNUTLS_VERSION_MINOR
  58 #define GNUTLS_VERSION_PATCH LIBGNUTLS_VERSION_PATCH
  59 #endif
  60
  61 // These don't exist in older GnuTLS versions
  62 #if ((GNUTLS_VERSION_MAJOR > 2) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 1) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR == 1 && GNUTLS_VERSION_PATCH >= 7))
  63 #define GNUTLS_NEW_PRIO_API
  64 #endif
  65
  66 #if(GNUTLS_VERSION_MAJOR < 2)
  67 typedef gnutls_certificate_credentials_t gnutls_certificate_credentials;
  68 typedef gnutls_dh_params_t gnutls_dh_params;
  69 #endif
  70
  71 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  72
  73 static std::vector<gnutls_x509_crt_t> x509_certs;
  74 static gnutls_x509_privkey_t x509_key;
  75 #if (GNUTLS_VERSION_MAJOR > 2 || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR >= 12))
  76 #define GNUTLS_NEW_CERT_CALLBACK_API
  77 typedef gnutls_retr2_st cert_cb_last_param_type;
  78 #else
  79 typedef gnutls_retr_st cert_cb_last_param_type;
  80 #endif
  81
  82 static int cert_callback(gnutls_session_t session, const gnutls_datum_t* req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t* sign_algos, int sign_algos_length, cert_cb_last_param_type* st);
  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 #ifdef GNUTLS_HAS_RND
  91                 gnutls_rnd(GNUTLS_RND_RANDOM, buffer, len);
  92 #else
  93                 gcry_randomize(buffer, len, GCRY_STRONG_RANDOM);
  94 #endif
  95         }
  96 };
  97
  98 /** Represents an SSL user's extra data
  99  */
 100 class issl_session
 101 {
 102 public:
 103         StreamSocket* socket;
 104         gnutls_session_t sess;
 105         issl_status status;
 106         reference<ssl_cert> cert;
 107
 108         issl_session() : socket(NULL), sess(NULL) {}
 109 };
 110
 111 class GnuTLSIOHook : public SSLIOHook
 112 {
 113  private:
 114         void InitSession(StreamSocket* user, bool me_server)
 115         {
 116                 issl_session* session = &sessions[user->GetFd()];
 117
 118                 gnutls_init(&session->sess, me_server ? GNUTLS_SERVER : GNUTLS_CLIENT);
 119                 session->socket = user;
 120
 121                 #ifdef GNUTLS_NEW_PRIO_API
 122                 gnutls_priority_set(session->sess, priority);
 123                 #else
 124                 gnutls_set_default_priority(session->sess);
 125                 #endif
 126                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 127                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 128                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(session));
 129                 gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
 130                 gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
 131
 132                 if (me_server)
 133                         gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 134
 135                 Handshake(session, user);
 136         }
 137
 138         void CloseSession(issl_session* session)
 139         {
 140                 if (session->sess)
 141                 {
 142                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 143                         gnutls_deinit(session->sess);
 144                 }
 145                 session->socket = NULL;
 146                 session->sess = NULL;
 147                 session->cert = NULL;
 148                 session->status = ISSL_NONE;
 149         }
 150
 151         bool Handshake(issl_session* session, StreamSocket* user)
 152         {
 153                 int ret = gnutls_handshake(session->sess);
 154
 155                 if (ret < 0)
 156                 {
 157                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 158                         {
 159                                 // Handshake needs resuming later, read() or write() would have blocked.
 160
 161                                 if(gnutls_record_get_direction(session->sess) == 0)
 162                                 {
 163                                         // gnutls_handshake() wants to read() again.
 164                                         session->status = ISSL_HANDSHAKING_READ;
 165                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 166                                 }
 167                                 else
 168                                 {
 169                                         // gnutls_handshake() wants to write() again.
 170                                         session->status = ISSL_HANDSHAKING_WRITE;
 171                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 172                                 }
 173                         }
 174                         else
 175                         {
 176                                 user->SetError("Handshake Failed - " + std::string(gnutls_strerror(ret)));
 177                                 CloseSession(session);
 178                                 session->status = ISSL_CLOSING;
 179                         }
 180
 181                         return false;
 182                 }
 183                 else
 184                 {
 185                         // Change the seesion state
 186                         session->status = ISSL_HANDSHAKEN;
 187
 188                         VerifyCertificate(session,user);
 189
 190                         // Finish writing, if any left
 191                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 192
 193                         return true;
 194                 }
 195         }
 196
 197         void VerifyCertificate(issl_session* session, StreamSocket* user)
 198         {
 199                 if (!session->sess || !user)
 200                         return;
 201
 202                 unsigned int status;
 203                 const gnutls_datum_t* cert_list;
 204                 int ret;
 205                 unsigned int cert_list_size;
 206                 gnutls_x509_crt_t cert;
 207                 char str[512];
 208                 unsigned char digest[512];
 209                 size_t digest_size = sizeof(digest);
 210                 size_t name_size = sizeof(str);
 211                 ssl_cert* certinfo = new ssl_cert;
 212                 session->cert = certinfo;
 213
 214                 /* This verification function uses the trusted CAs in the credentials
 215                  * structure. So you must have installed one or more CA certificates.
 216                  */
 217                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 218
 219                 if (ret < 0)
 220                 {
 221                         certinfo->error = std::string(gnutls_strerror(ret));
 222                         return;
 223                 }
 224
 225                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 226                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 227                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 228                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 229
 230                 /* Up to here the process is the same for X.509 certificates and
 231                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 232                  * be easily extended to work with openpgp keys as well.
 233                  */
 234                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 235                 {
 236                         certinfo->error = "No X509 keys sent";
 237                         return;
 238                 }
 239
 240                 ret = gnutls_x509_crt_init(&cert);
 241                 if (ret < 0)
 242                 {
 243                         certinfo->error = gnutls_strerror(ret);
 244                         return;
 245                 }
 246
 247                 cert_list_size = 0;
 248                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 249                 if (cert_list == NULL)
 250                 {
 251                         certinfo->error = "No certificate was found";
 252                         goto info_done_dealloc;
 253                 }
 254
 255                 /* This is not a real world example, since we only check the first
 256                  * certificate in the given chain.
 257                  */
 258
 259                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 260                 if (ret < 0)
 261                 {
 262                         certinfo->error = gnutls_strerror(ret);
 263                         goto info_done_dealloc;
 264                 }
 265
 266                 gnutls_x509_crt_get_dn(cert, str, &name_size);
 267                 certinfo->dn = str;
 268
 269                 gnutls_x509_crt_get_issuer_dn(cert, str, &name_size);
 270                 certinfo->issuer = str;
 271
 272                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, hash, digest, &digest_size)) < 0)
 273                 {
 274                         certinfo->error = gnutls_strerror(ret);
 275                 }
 276                 else
 277                 {
 278                         certinfo->fingerprint = BinToHex(digest, digest_size);
 279                 }
 280
 281                 /* Beware here we do not check for errors.
 282                  */
 283                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 284                 {
 285                         certinfo->error = "Not activated, or expired certificate";
 286                 }
 287
 288 info_done_dealloc:
 289                 gnutls_x509_crt_deinit(cert);
 290         }
 291
 292         static const char* UnknownIfNULL(const char* str)
 293         {
 294                 return str ? str : "UNKNOWN";
 295         }
 296
 297         static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t session_wrap, void* buffer, size_t size)
 298         {
 299                 issl_session* session = reinterpret_cast<issl_session*>(session_wrap);
 300                 if (session->socket->GetEventMask() & FD_READ_WILL_BLOCK)
 301                 {
 302 #ifdef _WIN32
 303                         gnutls_transport_set_errno(session->sess, EAGAIN);
 304 #else
 305                         errno = EAGAIN;
 306 #endif
 307                         return -1;
 308                 }
 309
 310                 int rv = ServerInstance->SE->Recv(session->socket, reinterpret_cast<char *>(buffer), size, 0);
 311
 312 #ifdef _WIN32
 313                 if (rv < 0)
 314                 {
 315                         /* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
 316                          * and then set errno appropriately.
 317                          * The gnutls library may also have a different errno variable than us, see
 318                          * gnutls_transport_set_errno(3).
 319                          */
 320                         gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
 321                 }
 322 #endif
 323
 324                 if (rv < (int)size)
 325                         ServerInstance->SE->ChangeEventMask(session->socket, FD_READ_WILL_BLOCK);
 326                 return rv;
 327         }
 328
 329         static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t session_wrap, const void* buffer, size_t size)
 330         {
 331                 issl_session* session = reinterpret_cast<issl_session*>(session_wrap);
 332                 if (session->socket->GetEventMask() & FD_WRITE_WILL_BLOCK)
 333                 {
 334 #ifdef _WIN32
 335                         gnutls_transport_set_errno(session->sess, EAGAIN);
 336 #else
 337                         errno = EAGAIN;
 338 #endif
 339                         return -1;
 340                 }
 341
 342                 int rv = ServerInstance->SE->Send(session->socket, reinterpret_cast<const char *>(buffer), size, 0);
 343
 344 #ifdef _WIN32
 345                 if (rv < 0)
 346                 {
 347                         /* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
 348                          * and then set errno appropriately.
 349                          * The gnutls library may also have a different errno variable than us, see
 350                          * gnutls_transport_set_errno(3).
 351                          */
 352                         gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
 353                 }
 354 #endif
 355
 356                 if (rv < (int)size)
 357                         ServerInstance->SE->ChangeEventMask(session->socket, FD_WRITE_WILL_BLOCK);
 358                 return rv;
 359         }
 360
 361  public:
 362         issl_session* sessions;
 363         gnutls_certificate_credentials_t x509_cred;
 364
 365         gnutls_digest_algorithm_t hash;
 366         #ifdef GNUTLS_NEW_PRIO_API
 367         gnutls_priority_t priority;
 368         #endif
 369         int dh_bits;
 370
 371         GnuTLSIOHook(Module* parent)
 372                 : SSLIOHook(parent, "ssl/gnutls")
 373         {
 374                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 375         }
 376
 377         ~GnuTLSIOHook()
 378         {
 379                 delete[] sessions;
 380         }
 381
 382         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE
 383         {
 384                 issl_session* session = &sessions[user->GetFd()];
 385
 386                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 387                 if (session->sess)
 388                         return;
 389
 390                 InitSession(user, true);
 391         }
 392
 393         void OnStreamSocketConnect(StreamSocket* user) CXX11_OVERRIDE
 394         {
 395                 InitSession(user, false);
 396         }
 397
 398         void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE
 399         {
 400                 CloseSession(&sessions[user->GetFd()]);
 401         }
 402
 403         int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE
 404         {
 405                 issl_session* session = &sessions[user->GetFd()];
 406
 407                 if (!session->sess)
 408                 {
 409                         CloseSession(session);
 410                         user->SetError("No SSL session");
 411                         return -1;
 412                 }
 413
 414                 if (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE)
 415                 {
 416                         // The handshake isn't finished, try to finish it.
 417
 418                         if(!Handshake(session, user))
 419                         {
 420                                 if (session->status != ISSL_CLOSING)
 421                                         return 0;
 422                                 return -1;
 423                         }
 424                 }
 425
 426                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 427
 428                 if (session->status == ISSL_HANDSHAKEN)
 429                 {
 430                         char* buffer = ServerInstance->GetReadBuffer();
 431                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 432                         int ret = gnutls_record_recv(session->sess, buffer, bufsiz);
 433                         if (ret > 0)
 434                         {
 435                                 recvq.append(buffer, ret);
 436                                 return 1;
 437                         }
 438                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 439                         {
 440                                 return 0;
 441                         }
 442                         else if (ret == 0)
 443                         {
 444                                 user->SetError("Connection closed");
 445                                 CloseSession(session);
 446                                 return -1;
 447                         }
 448                         else
 449                         {
 450                                 user->SetError(gnutls_strerror(ret));
 451                                 CloseSession(session);
 452                                 return -1;
 453                         }
 454                 }
 455                 else if (session->status == ISSL_CLOSING)
 456                         return -1;
 457
 458                 return 0;
 459         }
 460
 461         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq) CXX11_OVERRIDE
 462         {
 463                 issl_session* session = &sessions[user->GetFd()];
 464
 465                 if (!session->sess)
 466                 {
 467                         CloseSession(session);
 468                         user->SetError("No SSL session");
 469                         return -1;
 470                 }
 471
 472                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 473                 {
 474                         // The handshake isn't finished, try to finish it.
 475                         Handshake(session, user);
 476                         if (session->status != ISSL_CLOSING)
 477                                 return 0;
 478                         return -1;
 479                 }
 480
 481                 int ret = 0;
 482
 483                 if (session->status == ISSL_HANDSHAKEN)
 484                 {
 485                         ret = gnutls_record_send(session->sess, sendq.data(), sendq.length());
 486
 487                         if (ret == (int)sendq.length())
 488                         {
 489                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE);
 490                                 return 1;
 491                         }
 492                         else if (ret > 0)
 493                         {
 494                                 sendq = sendq.substr(ret);
 495                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 496                                 return 0;
 497                         }
 498                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED || ret == 0)
 499                         {
 500                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 501                                 return 0;
 502                         }
 503                         else // (ret < 0)
 504                         {
 505                                 user->SetError(gnutls_strerror(ret));
 506                                 CloseSession(session);
 507                                 return -1;
 508                         }
 509                 }
 510
 511                 return 0;
 512         }
 513
 514         ssl_cert* GetCertificate(StreamSocket* sock) CXX11_OVERRIDE
 515         {
 516                 int fd = sock->GetFd();
 517                 issl_session* session = &sessions[fd];
 518                 return session->cert;
 519         }
 520
 521         void TellCiphersAndFingerprint(LocalUser* user)
 522         {
 523                 const gnutls_session_t& sess = sessions[user->eh.GetFd()].sess;
 524                 if (sess)
 525                 {
 526                         std::string text = "*** You are connected using SSL cipher '";
 527
 528                         text += UnknownIfNULL(gnutls_kx_get_name(gnutls_kx_get(sess)));
 529                         text.append("-").append(UnknownIfNULL(gnutls_cipher_get_name(gnutls_cipher_get(sess)))).append("-");
 530                         text.append(UnknownIfNULL(gnutls_mac_get_name(gnutls_mac_get(sess)))).append("'");
 531
 532                         ssl_cert* cert = sessions[user->eh.GetFd()].cert;
 533                         if (!cert->fingerprint.empty())
 534                                 text += " and your SSL fingerprint is " + cert->fingerprint;
 535
 536                         user->WriteNotice(text);
 537                 }
 538         }
 539 };
 540
 541 static int cert_callback(gnutls_session_t sess, const gnutls_datum_t* req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t* sign_algos, int sign_algos_length, cert_cb_last_param_type* st)
 542 {
 543 #ifndef GNUTLS_NEW_CERT_CALLBACK_API
 544         st->type = GNUTLS_CRT_X509;
 545 #else
 546         st->cert_type = GNUTLS_CRT_X509;
 547         st->key_type = GNUTLS_PRIVKEY_X509;
 548 #endif
 549         st->ncerts = x509_certs.size();
 550         st->cert.x509 = &x509_certs[0];
 551         st->key.x509 = x509_key;
 552         st->deinit_all = 0;
 553
 554         return 0;
 555 }
 556
 557 class ModuleSSLGnuTLS : public Module
 558 {
 559         GnuTLSIOHook iohook;
 560
 561         gnutls_dh_params_t dh_params;
 562
 563         std::string sslports;
 564
 565         bool cred_alloc;
 566         bool dh_alloc;
 567
 568         RandGen randhandler;
 569
 570  public:
 571         ModuleSSLGnuTLS() : iohook(this)
 572         {
 573 #ifndef GNUTLS_HAS_RND
 574                 gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
 575 #endif
 576
 577                 gnutls_global_init(); // This must be called once in the program
 578                 gnutls_x509_privkey_init(&x509_key);
 579
 580                 #ifdef GNUTLS_NEW_PRIO_API
 581                 // Init this here so it's always initialized, avoids an extra boolean
 582                 gnutls_priority_init(&iohook.priority, "NORMAL", NULL);
 583                 #endif
 584
 585                 cred_alloc = false;
 586                 dh_alloc = false;
 587         }
 588
 589         void init() CXX11_OVERRIDE
 590         {
 591                 // Needs the flag as it ignores a plain /rehash
 592                 OnModuleRehash(NULL,"ssl");
 593
 594                 ServerInstance->GenRandom = &randhandler;
 595
 596                 // Void return, guess we assume success
 597                 gnutls_certificate_set_dh_params(iohook.x509_cred, dh_params);
 598         }
 599
 600         void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
 601         {
 602                 sslports.clear();
 603
 604                 ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
 605
 606                 if (Conf->getBool("showports", true))
 607                 {
 608                         sslports = Conf->getString("advertisedports");
 609                         if (!sslports.empty())
 610                                 return;
 611
 612                         for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 613                         {
 614                                 ListenSocket* port = ServerInstance->ports[i];
 615                                 if (port->bind_tag->getString("ssl") != "gnutls")
 616                                         continue;
 617
 618                                 const std::string& portid = port->bind_desc;
 619                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Enabling SSL for port %s", portid.c_str());
 620
 621                                 if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
 622                                 {
 623                                         /*
 624                                          * Found an SSL port for clients that is not bound to 127.0.0.1 and handled by us, display
 625                                          * the IP:port in ISUPPORT.
 626                                          *
 627                                          * We used to advertise all ports seperated by a ';' char that matched the above criteria,
 628                                          * but this resulted in too long ISUPPORT lines if there were lots of ports to be displayed.
 629                                          * To solve this by default we now only display the first IP:port found and let the user
 630                                          * configure the exact value for the 005 token, if necessary.
 631                                          */
 632                                         sslports = portid;
 633                                         break;
 634                                 }
 635                         }
 636                 }
 637         }
 638
 639         void OnModuleRehash(User* user, const std::string &param) CXX11_OVERRIDE
 640         {
 641                 if(param != "ssl")
 642                         return;
 643
 644                 std::string keyfile;
 645                 std::string certfile;
 646                 std::string cafile;
 647                 std::string crlfile;
 648
 649                 ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
 650
 651                 cafile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("cafile", "ca.pem"));
 652                 crlfile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("crlfile", "crl.pem"));
 653                 certfile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("certfile", "cert.pem"));
 654                 keyfile = ServerInstance->Config->Paths.PrependConfig(Conf->getString("keyfile", "key.pem"));
 655                 int dh_bits = Conf->getInt("dhbits");
 656                 std::string hashname = Conf->getString("hash", "md5");
 657
 658                 // The GnuTLS manual states that the gnutls_set_default_priority()
 659                 // call we used previously when initializing the session is the same
 660                 // as setting the "NORMAL" priority string.
 661                 // Thus if the setting below is not in the config we will behave exactly
 662                 // the same as before, when the priority setting wasn't available.
 663                 std::string priorities = Conf->getString("priority", "NORMAL");
 664
 665                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 666                         dh_bits = 1024;
 667
 668                 iohook.dh_bits = dh_bits;
 669
 670                 // As older versions of gnutls can't do this, let's disable it where needed.
 671 #ifdef GNUTLS_HAS_MAC_GET_ID
 672                 // As gnutls_digest_algorithm_t and gnutls_mac_algorithm_t are mapped 1:1, we can do this
 673                 // There is no gnutls_dig_get_id() at the moment, but it may come later
 674                 iohook.hash = (gnutls_digest_algorithm_t)gnutls_mac_get_id(hashname.c_str());
 675                 if (iohook.hash == GNUTLS_DIG_UNKNOWN)
 676                         throw ModuleException("Unknown hash type " + hashname);
 677
 678                 // Check if the user is walking around with their head in the ass,
 679                 // giving us something that is a valid MAC but not digest
 680                 gnutls_hash_hd_t is_digest;
 681                 if (gnutls_hash_init(&is_digest, iohook.hash) < 0)
 682                         throw ModuleException("Unknown hash type " + hashname);
 683                 gnutls_hash_deinit(is_digest, NULL);
 684 #else
 685                 if (hashname == "md5")
 686                         iohook.hash = GNUTLS_DIG_MD5;
 687                 else if (hashname == "sha1")
 688                         iohook.hash = GNUTLS_DIG_SHA1;
 689                 else
 690                         throw ModuleException("Unknown hash type " + hashname);
 691 #endif
 692
 693                 int ret;
 694
 695                 if (dh_alloc)
 696                 {
 697                         gnutls_dh_params_deinit(dh_params);
 698                         dh_alloc = false;
 699                         dh_params = NULL;
 700                 }
 701
 702                 if (cred_alloc)
 703                 {
 704                         // Deallocate the old credentials
 705                         gnutls_certificate_free_credentials(iohook.x509_cred);
 706
 707                         for(unsigned int i=0; i < x509_certs.size(); i++)
 708                                 gnutls_x509_crt_deinit(x509_certs[i]);
 709                         x509_certs.clear();
 710                 }
 711
 712                 ret = gnutls_certificate_allocate_credentials(&iohook.x509_cred);
 713                 cred_alloc = (ret >= 0);
 714                 if (!cred_alloc)
 715                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 716
 717                 if((ret =gnutls_certificate_set_x509_trust_file(iohook.x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 718                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));
 719
 720                 if((ret = gnutls_certificate_set_x509_crl_file (iohook.x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 721                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));
 722
 723                 FileReader reader;
 724
 725                 reader.Load(certfile);
 726                 std::string cert_string = reader.GetString();
 727                 gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), static_cast<unsigned int>(cert_string.length()) };
 728
 729                 reader.Load(keyfile);
 730                 std::string key_string = reader.GetString();
 731                 gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), static_cast<unsigned int>(key_string.length()) };
 732
 733                 // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 734                 unsigned int certcount = 3;
 735                 x509_certs.resize(certcount);
 736                 ret = gnutls_x509_crt_list_import(&x509_certs[0], &certcount, &cert_datum, GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
 737                 if (ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
 738                 {
 739                         // 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
 740                         x509_certs.resize(certcount);
 741                         ret = gnutls_x509_crt_list_import(&x509_certs[0], &certcount, &cert_datum, GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
 742                 }
 743
 744                 if (ret <= 0)
 745                 {
 746                         // clear the vector so we won't call gnutls_x509_crt_deinit() on the (uninited) certs later
 747                         x509_certs.clear();
 748                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + ((ret < 0) ? (std::string(gnutls_strerror(ret))) : "No certs could be read"));
 749                 }
 750                 x509_certs.resize(ret);
 751
 752                 if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0)
 753                         throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret)));
 754
 755                 if((ret = gnutls_certificate_set_x509_key(iohook.x509_cred, &x509_certs[0], certcount, x509_key)) < 0)
 756                         throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
 757
 758                 #ifdef GNUTLS_NEW_PRIO_API
 759                 // It's safe to call this every time as we cannot have this uninitialized, see constructor and below.
 760                 gnutls_priority_deinit(iohook.priority);
 761
 762                 // Try to set the priorities for ciphers, kex methods etc. to the user supplied string
 763                 // If the user did not supply anything then the string is already set to "NORMAL"
 764                 const char* priocstr = priorities.c_str();
 765                 const char* prioerror;
 766
 767                 if ((ret = gnutls_priority_init(&iohook.priority, priocstr, &prioerror)) < 0)
 768                 {
 769                         // gnutls did not understand the user supplied string, log and fall back to the default priorities
 770                         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));
 771                         gnutls_priority_init(&iohook.priority, "NORMAL", NULL);
 772                 }
 773
 774                 #else
 775                 if (priorities != "NORMAL")
 776                         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.");
 777                 #endif
 778
 779                 #if(GNUTLS_VERSION_MAJOR < 2 || ( GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR < 12 ) )
 780                 gnutls_certificate_client_set_retrieve_function (iohook.x509_cred, cert_callback);
 781                 #else
 782                 gnutls_certificate_set_retrieve_function (iohook.x509_cred, cert_callback);
 783                 #endif
 784                 ret = gnutls_dh_params_init(&dh_params);
 785                 dh_alloc = (ret >= 0);
 786                 if (!dh_alloc)
 787                 {
 788                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 789                         return;
 790                 }
 791
 792                 std::string dhfile = Conf->getString("dhfile");
 793                 if (!dhfile.empty())
 794                 {
 795                         // Try to load DH params from file
 796                         reader.Load(dhfile);
 797                         std::string dhstring = reader.GetString();
 798                         gnutls_datum_t dh_datum = { (unsigned char*)dhstring.data(), static_cast<unsigned int>(dhstring.length()) };
 799
 800                         if ((ret = gnutls_dh_params_import_pkcs3(dh_params, &dh_datum, GNUTLS_X509_FMT_PEM)) < 0)
 801                         {
 802                                 // File unreadable or GnuTLS was unhappy with the contents, generate the DH primes now
 803                                 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));
 804                                 GenerateDHParams();
 805                         }
 806                 }
 807                 else
 808                 {
 809                         GenerateDHParams();
 810                 }
 811         }
 812
 813         void GenerateDHParams()
 814         {
 815                 // Generate Diffie Hellman parameters - for use with DHE
 816                 // kx algorithms. These should be discarded and regenerated
 817                 // once a day, once a week or once a month. Depending on the
 818                 // security requirements.
 819
 820                 if (!dh_alloc)
 821                         return;
 822
 823                 int ret;
 824
 825                 if((ret = gnutls_dh_params_generate2(dh_params, iohook.dh_bits)) < 0)
 826                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Failed to generate DH parameters (%d bits): %s", iohook.dh_bits, gnutls_strerror(ret));
 827         }
 828
 829         ~ModuleSSLGnuTLS()
 830         {
 831                 for(unsigned int i=0; i < x509_certs.size(); i++)
 832                         gnutls_x509_crt_deinit(x509_certs[i]);
 833
 834                 gnutls_x509_privkey_deinit(x509_key);
 835                 #ifdef GNUTLS_NEW_PRIO_API
 836                 gnutls_priority_deinit(iohook.priority);
 837                 #endif
 838
 839                 if (dh_alloc)
 840                         gnutls_dh_params_deinit(dh_params);
 841                 if (cred_alloc)
 842                         gnutls_certificate_free_credentials(iohook.x509_cred);
 843
 844                 gnutls_global_deinit();
 845                 ServerInstance->GenRandom = &ServerInstance->HandleGenRandom;
 846         }
 847
 848         void OnCleanup(int target_type, void* item) CXX11_OVERRIDE
 849         {
 850                 if(target_type == TYPE_USER)
 851                 {
 852                         LocalUser* user = IS_LOCAL(static_cast<User*>(item));
 853
 854                         if (user && user->eh.GetIOHook() == &iohook)
 855                         {
 856                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 857                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 858                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 859                         }
 860                 }
 861         }
 862
 863         Version GetVersion() CXX11_OVERRIDE
 864         {
 865                 return Version("Provides SSL support for clients", VF_VENDOR);
 866         }
 867
 868         void On005Numeric(std::map<std::string, std::string>& tokens) CXX11_OVERRIDE
 869         {
 870                 if (!sslports.empty())
 871                         tokens["SSL"] = sslports;
 872         }
 873
 874         void OnHookIO(StreamSocket* user, ListenSocket* lsb) CXX11_OVERRIDE
 875         {
 876                 if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "gnutls")
 877                 {
 878                         /* Hook the user with our module */
 879                         user->AddIOHook(&iohook);
 880                 }
 881         }
 882
 883         void OnUserConnect(LocalUser* user) CXX11_OVERRIDE
 884         {
 885                 if (user->eh.GetIOHook() == &iohook)
 886                         iohook.TellCiphersAndFingerprint(user);
 887         }
 888 };
 889
 890 MODULE_INIT(ModuleSSLGnuTLS)