src/modules/extra/m_ssl_openssl.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
   5  *   Copyright (C) 2008 Pippijn van Steenhoven <pip88nl@gmail.com>
   6  *   Copyright (C) 2006-2008 Craig Edwards <craigedwards@brainbox.cc>
   7  *   Copyright (C) 2008 Thomas Stagner <aquanight@inspircd.org>
   8  *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
   9  *   Copyright (C) 2006 Oliver Lupton <oliverlupton@gmail.com>
  10  *
  11  * This file is part of InspIRCd.  InspIRCd is free software: you can
  12  * redistribute it and/or modify it under the terms of the GNU General Public
  13  * License as published by the Free Software Foundation, version 2.
  14  *
  15  * This program is distributed in the hope that it will be useful, but WITHOUT
  16  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  17  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24
  25 #include "inspircd.h"
  26 #include <openssl/ssl.h>
  27 #include <openssl/err.h>
  28 #include "ssl.h"
  29
  30 #ifdef WINDOWS
  31 # pragma comment(lib, "libcrypto.lib")
  32 # pragma comment(lib, "libssl.lib")
  33 # pragma comment(lib, "user32.lib")
  34 # pragma comment(lib, "advapi32.lib")
  35 # pragma comment(lib, "libgcc.lib")
  36 # pragma comment(lib, "libmingwex.lib")
  37 # pragma comment(lib, "gdi32.lib")
  38 # undef MAX_DESCRIPTORS
  39 # define MAX_DESCRIPTORS 10000
  40 #endif
  41
  42 /* $ModDesc: Provides SSL support for clients */
  43
  44 /* $LinkerFlags: if("USE_FREEBSD_BASE_SSL") -lssl -lcrypto */
  45 /* $CompileFlags: if(!"USE_FREEBSD_BASE_SSL") pkgconfversion("openssl","0.9.7") pkgconfincludes("openssl","/openssl/ssl.h","") */
  46 /* $LinkerFlags: if(!"USE_FREEBSD_BASE_SSL") rpath("pkg-config --libs openssl") pkgconflibs("openssl","/libssl.so","-lssl -lcrypto -ldl") */
  47
  48 /* $NoPedantic */
  49
  50
  51 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_OPEN };
  52
  53 static bool SelfSigned = false;
  54
  55 char* get_error()
  56 {
  57         return ERR_error_string(ERR_get_error(), NULL);
  58 }
  59
  60 static int error_callback(const char *str, size_t len, void *u);
  61
  62 /** Represents an SSL user's extra data
  63  */
  64 class issl_session
  65 {
  66 public:
  67         SSL* sess;
  68         issl_status status;
  69         reference<ssl_cert> cert;
  70
  71         int fd;
  72         bool outbound;
  73         bool data_to_write;
  74
  75         issl_session()
  76         {
  77                 outbound = false;
  78                 data_to_write = false;
  79         }
  80 };
  81
  82 static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx)
  83 {
  84         /* XXX: This will allow self signed certificates.
  85          * In the future if we want an option to not allow this,
  86          * we can just return preverify_ok here, and openssl
  87          * will boot off self-signed and invalid peer certs.
  88          */
  89         int ve = X509_STORE_CTX_get_error(ctx);
  90
  91         SelfSigned = (ve == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
  92
  93         return 1;
  94 }
  95
  96 class ModuleSSLOpenSSL : public Module
  97 {
  98         int inbufsize;
  99         issl_session* sessions;
 100
 101         SSL_CTX* ctx;
 102         SSL_CTX* clictx;
 103
 104         char cipher[MAXBUF];
 105
 106         std::string sslports;
 107         bool use_sha;
 108
 109         ServiceProvider iohook;
 110  public:
 111
 112         ModuleSSLOpenSSL() : iohook(this, "ssl/openssl", SERVICE_IOHOOK)
 113         {
 114                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 115
 116                 // Not rehashable...because I cba to reduce all the sizes of existing buffers.
 117                 inbufsize = ServerInstance->Config->NetBufferSize;
 118
 119                 /* Global SSL library initialization*/
 120                 SSL_library_init();
 121                 SSL_load_error_strings();
 122
 123                 /* Build our SSL contexts:
 124                  * NOTE: OpenSSL makes us have two contexts, one for servers and one for clients. ICK.
 125                  */
 126                 ctx = SSL_CTX_new( SSLv23_server_method() );
 127                 clictx = SSL_CTX_new( SSLv23_client_method() );
 128
 129                 SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 130                 SSL_CTX_set_mode(clictx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 131
 132                 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 133                 SSL_CTX_set_verify(clictx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 134         }
 135
 136         void init()
 137         {
 138                 // Needs the flag as it ignores a plain /rehash
 139                 OnModuleRehash(NULL,"ssl");
 140                 Implementation eventlist[] = { I_On005Numeric, I_OnRehash, I_OnModuleRehash, I_OnHookIO, I_OnUserConnect };
 141                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 142                 ServerInstance->Modules->AddService(iohook);
 143         }
 144
 145         void OnHookIO(StreamSocket* user, ListenSocket* lsb)
 146         {
 147                 if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "openssl")
 148                 {
 149                         /* Hook the user with our module */
 150                         user->AddIOHook(this);
 151                 }
 152         }
 153
 154         void OnRehash(User* user)
 155         {
 156                 sslports.clear();
 157
 158                 ConfigTag* Conf = ServerInstance->Config->ConfValue("openssl");
 159
 160                 if (Conf->getBool("showports", true))
 161                 {
 162                         for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 163                         {
 164                                 ListenSocket* port = ServerInstance->ports[i];
 165                                 if (port->bind_tag->getString("ssl") != "openssl")
 166                                         continue;
 167
 168                                 std::string portid = port->bind_desc;
 169                                 ServerInstance->Logs->Log("m_ssl_openssl", DEFAULT, "m_ssl_openssl.so: Enabling SSL for port %s", portid.c_str());
 170                                 if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
 171                                         sslports.append(portid).append(";");
 172                         }
 173
 174                         if (!sslports.empty())
 175                                 sslports.erase(sslports.end() - 1);
 176                 }
 177         }
 178
 179         void OnModuleRehash(User* user, const std::string &param)
 180         {
 181                 if (param != "ssl")
 182                         return;
 183
 184                 std::string keyfile;
 185                 std::string certfile;
 186                 std::string cafile;
 187                 std::string dhfile;
 188                 OnRehash(user);
 189
 190                 ConfigTag* conf = ServerInstance->Config->ConfValue("openssl");
 191
 192                 cafile   = conf->getString("cafile", "conf/ca.pem");
 193                 certfile = conf->getString("certfile", "conf/cert.pem");
 194                 keyfile  = conf->getString("keyfile", "conf/key.pem");
 195                 dhfile   = conf->getString("dhfile", "conf/dhparams.pem");
 196                 std::string hash = conf->getString("hash", "md5");
 197                 if (hash != "sha1" && hash != "md5")
 198                         throw ModuleException("Unknown hash type " + hash);
 199                 use_sha = (hash == "sha1");
 200
 201
 202                 /* Load our keys and certificates
 203                  * NOTE: OpenSSL's error logging API sucks, don't blame us for this clusterfuck.
 204                  */
 205                 if ((!SSL_CTX_use_certificate_chain_file(ctx, certfile.c_str())) || (!SSL_CTX_use_certificate_chain_file(clictx, certfile.c_str())))
 206                 {
 207                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't read certificate file %s. %s", certfile.c_str(), strerror(errno));
 208                         ERR_print_errors_cb(error_callback, this);
 209                 }
 210
 211                 if (((!SSL_CTX_use_PrivateKey_file(ctx, keyfile.c_str(), SSL_FILETYPE_PEM))) || (!SSL_CTX_use_PrivateKey_file(clictx, keyfile.c_str(), SSL_FILETYPE_PEM)))
 212                 {
 213                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't read key file %s. %s", keyfile.c_str(), strerror(errno));
 214                         ERR_print_errors_cb(error_callback, this);
 215                 }
 216
 217                 /* Load the CAs we trust*/
 218                 if (((!SSL_CTX_load_verify_locations(ctx, cafile.c_str(), 0))) || (!SSL_CTX_load_verify_locations(clictx, cafile.c_str(), 0)))
 219                 {
 220                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't read CA list from %s. %s", cafile.c_str(), strerror(errno));
 221                         ERR_print_errors_cb(error_callback, this);
 222                 }
 223
 224                 FILE* dhpfile = fopen(dhfile.c_str(), "r");
 225                 DH* ret;
 226
 227                 if (dhpfile == NULL)
 228                 {
 229                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so Couldn't open DH file %s: %s", dhfile.c_str(), strerror(errno));
 230                         throw ModuleException("Couldn't open DH file " + dhfile + ": " + strerror(errno));
 231                 }
 232                 else
 233                 {
 234                         ret = PEM_read_DHparams(dhpfile, NULL, NULL, NULL);
 235                         if ((SSL_CTX_set_tmp_dh(ctx, ret) < 0) || (SSL_CTX_set_tmp_dh(clictx, ret) < 0))
 236                         {
 237                                 ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Couldn't set DH parameters %s. SSL errors follow:", dhfile.c_str());
 238                                 ERR_print_errors_cb(error_callback, this);
 239                         }
 240                 }
 241
 242                 fclose(dhpfile);
 243         }
 244
 245         void On005Numeric(std::string &output)
 246         {
 247                 if (!sslports.empty())
 248                         output.append(" SSL=" + sslports);
 249         }
 250
 251         ~ModuleSSLOpenSSL()
 252         {
 253                 SSL_CTX_free(ctx);
 254                 SSL_CTX_free(clictx);
 255                 delete[] sessions;
 256         }
 257
 258         void OnUserConnect(LocalUser* user)
 259         {
 260                 if (user->eh.GetIOHook() == this)
 261                 {
 262                         if (sessions[user->eh.GetFd()].sess)
 263                         {
 264                                 if (!sessions[user->eh.GetFd()].cert->fingerprint.empty())
 265                                         user->WriteServ("NOTICE %s :*** You are connected using SSL fingerprint %s",
 266                                                 user->nick.c_str(), sessions[user->eh.GetFd()].cert->fingerprint.c_str());
 267                         }
 268                 }
 269         }
 270
 271         void OnCleanup(int target_type, void* item)
 272         {
 273                 if (target_type == TYPE_USER)
 274                 {
 275                         LocalUser* user = IS_LOCAL((User*)item);
 276
 277                         if (user && user->eh.GetIOHook() == this)
 278                         {
 279                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 280                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 281                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 282                         }
 283                 }
 284         }
 285
 286         Version GetVersion()
 287         {
 288                 return Version("Provides SSL support for clients", VF_VENDOR);
 289         }
 290
 291         void OnRequest(Request& request)
 292         {
 293                 if (strcmp("GET_SSL_CERT", request.id) == 0)
 294                 {
 295                         SocketCertificateRequest& req = static_cast<SocketCertificateRequest&>(request);
 296                         int fd = req.sock->GetFd();
 297                         issl_session* session = &sessions[fd];
 298
 299                         req.cert = session->cert;
 300                 }
 301         }
 302
 303         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 304         {
 305                 int fd = user->GetFd();
 306
 307                 issl_session* session = &sessions[fd];
 308
 309                 session->fd = fd;
 310                 session->sess = SSL_new(ctx);
 311                 session->status = ISSL_NONE;
 312                 session->outbound = false;
 313                 session->cert = NULL;
 314
 315                 if (session->sess == NULL)
 316                         return;
 317
 318                 if (SSL_set_fd(session->sess, fd) == 0)
 319                 {
 320                         ServerInstance->Logs->Log("m_ssl_openssl",DEBUG,"BUG: Can't set fd with SSL_set_fd: %d", fd);
 321                         return;
 322                 }
 323
 324                 Handshake(user, session);
 325         }
 326
 327         void OnStreamSocketConnect(StreamSocket* user)
 328         {
 329                 int fd = user->GetFd();
 330                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 331                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() -1))
 332                         return;
 333
 334                 issl_session* session = &sessions[fd];
 335
 336                 session->fd = fd;
 337                 session->sess = SSL_new(clictx);
 338                 session->status = ISSL_NONE;
 339                 session->outbound = true;
 340
 341                 if (session->sess == NULL)
 342                         return;
 343
 344                 if (SSL_set_fd(session->sess, fd) == 0)
 345                 {
 346                         ServerInstance->Logs->Log("m_ssl_openssl",DEBUG,"BUG: Can't set fd with SSL_set_fd: %d", fd);
 347                         return;
 348                 }
 349
 350                 Handshake(user, session);
 351         }
 352
 353         void OnStreamSocketClose(StreamSocket* user)
 354         {
 355                 int fd = user->GetFd();
 356                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 357                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 358                         return;
 359
 360                 CloseSession(&sessions[fd]);
 361         }
 362
 363         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 364         {
 365                 int fd = user->GetFd();
 366                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 367                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 368                         return -1;
 369
 370                 issl_session* session = &sessions[fd];
 371
 372                 if (!session->sess)
 373                 {
 374                         CloseSession(session);
 375                         return -1;
 376                 }
 377
 378                 if (session->status == ISSL_HANDSHAKING)
 379                 {
 380                         // The handshake isn't finished and it wants to read, try to finish it.
 381                         if (!Handshake(user, session))
 382                         {
 383                                 // Couldn't resume handshake.
 384                                 if (session->status == ISSL_NONE)
 385                                         return -1;
 386                                 return 0;
 387                         }
 388                 }
 389
 390                 // If we resumed the handshake then session->status will be ISSL_OPEN
 391
 392                 if (session->status == ISSL_OPEN)
 393                 {
 394                         char* buffer = ServerInstance->GetReadBuffer();
 395                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 396                         int ret = SSL_read(session->sess, buffer, bufsiz);
 397
 398                         if (ret > 0)
 399                         {
 400                                 recvq.append(buffer, ret);
 401                                 if (session->data_to_write)
 402                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE);
 403                                 return 1;
 404                         }
 405                         else if (ret == 0)
 406                         {
 407                                 // Client closed connection.
 408                                 CloseSession(session);
 409                                 return -1;
 410                         }
 411                         else if (ret < 0)
 412                         {
 413                                 int err = SSL_get_error(session->sess, ret);
 414
 415                                 if (err == SSL_ERROR_WANT_READ)
 416                                 {
 417                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ);
 418                                         return 0;
 419                                 }
 420                                 else if (err == SSL_ERROR_WANT_WRITE)
 421                                 {
 422                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 423                                         return 0;
 424                                 }
 425                                 else
 426                                 {
 427                                         CloseSession(session);
 428                                         return -1;
 429                                 }
 430                         }
 431                 }
 432
 433                 return 0;
 434         }
 435
 436         int OnStreamSocketWrite(StreamSocket* user, std::string& buffer)
 437         {
 438                 int fd = user->GetFd();
 439
 440                 issl_session* session = &sessions[fd];
 441
 442                 if (!session->sess)
 443                 {
 444                         CloseSession(session);
 445                         return -1;
 446                 }
 447
 448                 session->data_to_write = true;
 449
 450                 if (session->status == ISSL_HANDSHAKING)
 451                 {
 452                         if (!Handshake(user, session))
 453                         {
 454                                 // Couldn't resume handshake.
 455                                 if (session->status == ISSL_NONE)
 456                                         return -1;
 457                                 return 0;
 458                         }
 459                 }
 460
 461                 if (session->status == ISSL_OPEN)
 462                 {
 463                         int ret = SSL_write(session->sess, buffer.data(), buffer.size());
 464                         if (ret == (int)buffer.length())
 465                         {
 466                                 session->data_to_write = false;
 467                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 468                                 return 1;
 469                         }
 470                         else if (ret > 0)
 471                         {
 472                                 buffer = buffer.substr(ret);
 473                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 474                                 return 0;
 475                         }
 476                         else if (ret == 0)
 477                         {
 478                                 CloseSession(session);
 479                                 return -1;
 480                         }
 481                         else if (ret < 0)
 482                         {
 483                                 int err = SSL_get_error(session->sess, ret);
 484
 485                                 if (err == SSL_ERROR_WANT_WRITE)
 486                                 {
 487                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 488                                         return 0;
 489                                 }
 490                                 else if (err == SSL_ERROR_WANT_READ)
 491                                 {
 492                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ);
 493                                         return 0;
 494                                 }
 495                                 else
 496                                 {
 497                                         CloseSession(session);
 498                                         return -1;
 499                                 }
 500                         }
 501                 }
 502                 return 0;
 503         }
 504
 505         bool Handshake(StreamSocket* user, issl_session* session)
 506         {
 507                 int ret;
 508
 509                 if (session->outbound)
 510                         ret = SSL_connect(session->sess);
 511                 else
 512                         ret = SSL_accept(session->sess);
 513
 514                 if (ret < 0)
 515                 {
 516                         int err = SSL_get_error(session->sess, ret);
 517
 518                         if (err == SSL_ERROR_WANT_READ)
 519                         {
 520                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 521                                 session->status = ISSL_HANDSHAKING;
 522                                 return true;
 523                         }
 524                         else if (err == SSL_ERROR_WANT_WRITE)
 525                         {
 526                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 527                                 session->status = ISSL_HANDSHAKING;
 528                                 return true;
 529                         }
 530                         else
 531                         {
 532                                 CloseSession(session);
 533                         }
 534
 535                         return false;
 536                 }
 537                 else if (ret > 0)
 538                 {
 539                         // Handshake complete.
 540                         VerifyCertificate(session, user);
 541
 542                         session->status = ISSL_OPEN;
 543
 544                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 545
 546                         return true;
 547                 }
 548                 else if (ret == 0)
 549                 {
 550                         CloseSession(session);
 551                         return true;
 552                 }
 553
 554                 return true;
 555         }
 556
 557         void CloseSession(issl_session* session)
 558         {
 559                 if (session->sess)
 560                 {
 561                         SSL_shutdown(session->sess);
 562                         SSL_free(session->sess);
 563                 }
 564
 565                 session->sess = NULL;
 566                 session->status = ISSL_NONE;
 567                 errno = EIO;
 568         }
 569
 570         void VerifyCertificate(issl_session* session, StreamSocket* user)
 571         {
 572                 if (!session->sess || !user)
 573                         return;
 574
 575                 X509* cert;
 576                 ssl_cert* certinfo = new ssl_cert;
 577                 session->cert = certinfo;
 578                 unsigned int n;
 579                 unsigned char md[EVP_MAX_MD_SIZE];
 580                 const EVP_MD *digest = use_sha ? EVP_sha1() : EVP_md5();
 581
 582                 cert = SSL_get_peer_certificate((SSL*)session->sess);
 583
 584                 if (!cert)
 585                 {
 586                         certinfo->error = "Could not get peer certificate: "+std::string(get_error());
 587                         return;
 588                 }
 589
 590                 certinfo->invalid = (SSL_get_verify_result(session->sess) != X509_V_OK);
 591
 592                 if (SelfSigned)
 593                 {
 594                         certinfo->unknownsigner = false;
 595                         certinfo->trusted = true;
 596                 }
 597                 else
 598                 {
 599                         certinfo->unknownsigner = true;
 600                         certinfo->trusted = false;
 601                 }
 602
 603                 certinfo->dn = X509_NAME_oneline(X509_get_subject_name(cert),0,0);
 604                 certinfo->issuer = X509_NAME_oneline(X509_get_issuer_name(cert),0,0);
 605
 606                 if (!X509_digest(cert, digest, md, &n))
 607                 {
 608                         certinfo->error = "Out of memory generating fingerprint";
 609                 }
 610                 else
 611                 {
 612                         certinfo->fingerprint = irc::hex(md, n);
 613                 }
 614
 615                 if ((ASN1_UTCTIME_cmp_time_t(X509_get_notAfter(cert), ServerInstance->Time()) == -1) || (ASN1_UTCTIME_cmp_time_t(X509_get_notBefore(cert), ServerInstance->Time()) == 0))
 616                 {
 617                         certinfo->error = "Not activated, or expired certificate";
 618                 }
 619
 620                 X509_free(cert);
 621         }
 622 };
 623
 624 static int error_callback(const char *str, size_t len, void *u)
 625 {
 626         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "SSL error: " + std::string(str, len - 1));
 627
 628         //
 629         // XXX: Remove this line, it causes valgrind warnings...
 630         //
 631         // MD_update(&m, buf, j);
 632         //
 633         //
 634         // ... ONLY JOKING! :-)
 635         //
 636
 637         return 0;
 638 }
 639
 640 MODULE_INIT(ModuleSSLOpenSSL)