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  /* HACK: This prevents OpenSSL on OS X 10.7 and later from spewing deprecation
  25   * warnings for every single function call. As far as I (SaberUK) know, Apple
  26   * have no plans to remove OpenSSL so this warning just causes needless spam.
  27   */
  28 #ifdef __APPLE__
  29 # define __AVAILABILITYMACROS__
  30 # define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
  31 #endif
  32
  33 #include "inspircd.h"
  34 #include "iohook.h"
  35 #include <openssl/ssl.h>
  36 #include <openssl/err.h>
  37 #include "modules/ssl.h"
  38
  39 #ifdef _WIN32
  40 # pragma comment(lib, "libcrypto.lib")
  41 # pragma comment(lib, "libssl.lib")
  42 # pragma comment(lib, "user32.lib")
  43 # pragma comment(lib, "advapi32.lib")
  44 # pragma comment(lib, "libgcc.lib")
  45 # pragma comment(lib, "libmingwex.lib")
  46 # pragma comment(lib, "gdi32.lib")
  47 # undef MAX_DESCRIPTORS
  48 # define MAX_DESCRIPTORS 10000
  49 #endif
  50
  51 /* $CompileFlags: pkgconfversion("openssl","0.9.7") pkgconfincludes("openssl","/openssl/ssl.h","") -Wno-pedantic */
  52 /* $LinkerFlags: rpath("pkg-config --libs openssl") pkgconflibs("openssl","/libssl.so","-lssl -lcrypto") */
  53
  54 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_OPEN };
  55
  56 static bool SelfSigned = false;
  57
  58 char* get_error()
  59 {
  60         return ERR_error_string(ERR_get_error(), NULL);
  61 }
  62
  63 static int OnVerify(int preverify_ok, X509_STORE_CTX* ctx);
  64
  65 namespace OpenSSL
  66 {
  67         class Exception : public ModuleException
  68         {
  69          public:
  70                 Exception(const std::string& reason)
  71                         : ModuleException(reason) { }
  72         };
  73
  74         class DHParams
  75         {
  76                 DH* dh;
  77
  78          public:
  79                 DHParams(const std::string& filename)
  80                 {
  81                         FILE* dhpfile = fopen(filename.c_str(), "r");
  82                         if (dhpfile == NULL)
  83                                 throw Exception("Couldn't open DH file " + filename + ": " + strerror(errno));
  84
  85                         dh = PEM_read_DHparams(dhpfile, NULL, NULL, NULL);
  86                         fclose(dhpfile);
  87                         if (!dh)
  88                                 throw Exception("Couldn't read DH params from file " + filename);
  89                 }
  90
  91                 ~DHParams()
  92                 {
  93                         DH_free(dh);
  94                 }
  95
  96                 DH* get()
  97                 {
  98                         return dh;
  99                 }
 100         };
 101
 102         class Context
 103         {
 104                 SSL_CTX* const ctx;
 105
 106          public:
 107                 Context(SSL_CTX* context)
 108                         : ctx(context)
 109                 {
 110                         SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 111                         SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 112                 }
 113
 114                 ~Context()
 115                 {
 116                         SSL_CTX_free(ctx);
 117                 }
 118
 119                 bool SetDH(DHParams& dh)
 120                 {
 121                         return (SSL_CTX_set_tmp_dh(ctx, dh.get()) >= 0);
 122                 }
 123
 124                 bool SetCiphers(const std::string& ciphers)
 125                 {
 126                         return SSL_CTX_set_cipher_list(ctx, ciphers.c_str());
 127                 }
 128
 129                 bool SetCerts(const std::string& filename)
 130                 {
 131                         return SSL_CTX_use_certificate_chain_file(ctx, filename.c_str());
 132                 }
 133
 134                 bool SetPrivateKey(const std::string& filename)
 135                 {
 136                         return SSL_CTX_use_PrivateKey_file(ctx, filename.c_str(), SSL_FILETYPE_PEM);
 137                 }
 138
 139                 bool SetCA(const std::string& filename)
 140                 {
 141                         return SSL_CTX_load_verify_locations(ctx, filename.c_str(), 0);
 142                 }
 143
 144                 SSL* CreateSession()
 145                 {
 146                         return SSL_new(ctx);
 147                 }
 148         };
 149
 150         class Profile : public refcountbase
 151         {
 152                 /** Name of this profile
 153                  */
 154                 const std::string name;
 155
 156                 /** DH parameters in use
 157                  */
 158                 DHParams dh;
 159
 160                 /** OpenSSL makes us have two contexts, one for servers and one for clients
 161                  */
 162                 Context ctx;
 163                 Context clictx;
 164
 165                 /** Digest to use when generating fingerprints
 166                  */
 167                 const EVP_MD* digest;
 168
 169                 /** Last error, set by error_callback()
 170                  */
 171                 std::string lasterr;
 172
 173                 static int error_callback(const char* str, size_t len, void* u)
 174                 {
 175                         Profile* profile = reinterpret_cast<Profile*>(u);
 176                         profile->lasterr = std::string(str, len - 1);
 177                         return 0;
 178                 }
 179
 180          public:
 181                 Profile(const std::string& profilename, ConfigTag* tag)
 182                         : name(profilename)
 183                         , dh(ServerInstance->Config->Paths.PrependConfig(tag->getString("dhfile", "dh.pem")))
 184                         , ctx(SSL_CTX_new(SSLv23_server_method()))
 185                         , clictx(SSL_CTX_new(SSLv23_client_method()))
 186                 {
 187                         if ((!ctx.SetDH(dh)) || (!clictx.SetDH(dh)))
 188                                 throw Exception("Couldn't set DH parameters");
 189
 190                         std::string hash = tag->getString("hash", "md5");
 191                         digest = EVP_get_digestbyname(hash.c_str());
 192                         if (digest == NULL)
 193                                 throw Exception("Unknown hash type " + hash);
 194
 195                         std::string ciphers = tag->getString("ciphers");
 196                         if (!ciphers.empty())
 197                         {
 198                                 if ((!ctx.SetCiphers(ciphers)) || (!clictx.SetCiphers(ciphers)))
 199                                 {
 200                                         ERR_print_errors_cb(error_callback, this);
 201                                         throw Exception("Can't set cipher list to \"" + ciphers + "\" " + lasterr);
 202                                 }
 203                         }
 204
 205                         /* Load our keys and certificates
 206                          * NOTE: OpenSSL's error logging API sucks, don't blame us for this clusterfuck.
 207                          */
 208                         std::string filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("certfile", "cert.pem"));
 209                         if ((!ctx.SetCerts(filename)) || (!clictx.SetCerts(filename)))
 210                         {
 211                                 ERR_print_errors_cb(error_callback, this);
 212                                 throw Exception("Can't read certificate file: " + lasterr);
 213                         }
 214
 215                         filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("keyfile", "key.pem"));
 216                         if ((!ctx.SetPrivateKey(filename)) || (!clictx.SetPrivateKey(filename)))
 217                         {
 218                                 ERR_print_errors_cb(error_callback, this);
 219                                 throw Exception("Can't read key file: " + lasterr);
 220                         }
 221
 222                         // Load the CAs we trust
 223                         filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("cafile", "ca.pem"));
 224                         if ((!ctx.SetCA(filename)) || (!clictx.SetCA(filename)))
 225                         {
 226                                 ERR_print_errors_cb(error_callback, this);
 227                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Can't read CA list from %s. This is only a problem if you want to verify client certificates, otherwise it's safe to ignore this message. Error: %s", filename.c_str(), lasterr.c_str());
 228                         }
 229                 }
 230
 231                 const std::string& GetName() const { return name; }
 232                 SSL* CreateServerSession() { return ctx.CreateSession(); }
 233                 SSL* CreateClientSession() { return clictx.CreateSession(); }
 234                 const EVP_MD* GetDigest() { return digest; }
 235         };
 236 }
 237
 238 static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx)
 239 {
 240         /* XXX: This will allow self signed certificates.
 241          * In the future if we want an option to not allow this,
 242          * we can just return preverify_ok here, and openssl
 243          * will boot off self-signed and invalid peer certs.
 244          */
 245         int ve = X509_STORE_CTX_get_error(ctx);
 246
 247         SelfSigned = (ve == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
 248
 249         return 1;
 250 }
 251
 252 class OpenSSLIOHook : public SSLIOHook
 253 {
 254  private:
 255         SSL* sess;
 256         issl_status status;
 257         const bool outbound;
 258         bool data_to_write;
 259         reference<OpenSSL::Profile> profile;
 260
 261         bool Handshake(StreamSocket* user)
 262         {
 263                 int ret;
 264
 265                 if (outbound)
 266                         ret = SSL_connect(sess);
 267                 else
 268                         ret = SSL_accept(sess);
 269
 270                 if (ret < 0)
 271                 {
 272                         int err = SSL_get_error(sess, ret);
 273
 274                         if (err == SSL_ERROR_WANT_READ)
 275                         {
 276                                 SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 277                                 this->status = ISSL_HANDSHAKING;
 278                                 return true;
 279                         }
 280                         else if (err == SSL_ERROR_WANT_WRITE)
 281                         {
 282                                 SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 283                                 this->status = ISSL_HANDSHAKING;
 284                                 return true;
 285                         }
 286                         else
 287                         {
 288                                 CloseSession();
 289                         }
 290
 291                         return false;
 292                 }
 293                 else if (ret > 0)
 294                 {
 295                         // Handshake complete.
 296                         VerifyCertificate();
 297
 298                         status = ISSL_OPEN;
 299
 300                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 301
 302                         return true;
 303                 }
 304                 else if (ret == 0)
 305                 {
 306                         CloseSession();
 307                         return true;
 308                 }
 309
 310                 return true;
 311         }
 312
 313         void CloseSession()
 314         {
 315                 if (sess)
 316                 {
 317                         SSL_shutdown(sess);
 318                         SSL_free(sess);
 319                 }
 320                 sess = NULL;
 321                 certificate = NULL;
 322                 status = ISSL_NONE;
 323                 errno = EIO;
 324         }
 325
 326         void VerifyCertificate()
 327         {
 328                 X509* cert;
 329                 ssl_cert* certinfo = new ssl_cert;
 330                 this->certificate = certinfo;
 331                 unsigned int n;
 332                 unsigned char md[EVP_MAX_MD_SIZE];
 333
 334                 cert = SSL_get_peer_certificate(sess);
 335
 336                 if (!cert)
 337                 {
 338                         certinfo->error = "Could not get peer certificate: "+std::string(get_error());
 339                         return;
 340                 }
 341
 342                 certinfo->invalid = (SSL_get_verify_result(sess) != X509_V_OK);
 343
 344                 if (!SelfSigned)
 345                 {
 346                         certinfo->unknownsigner = false;
 347                         certinfo->trusted = true;
 348                 }
 349                 else
 350                 {
 351                         certinfo->unknownsigner = true;
 352                         certinfo->trusted = false;
 353                 }
 354
 355                 certinfo->dn = X509_NAME_oneline(X509_get_subject_name(cert),0,0);
 356                 certinfo->issuer = X509_NAME_oneline(X509_get_issuer_name(cert),0,0);
 357
 358                 if (!X509_digest(cert, profile->GetDigest(), md, &n))
 359                 {
 360                         certinfo->error = "Out of memory generating fingerprint";
 361                 }
 362                 else
 363                 {
 364                         certinfo->fingerprint = BinToHex(md, n);
 365                 }
 366
 367                 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))
 368                 {
 369                         certinfo->error = "Not activated, or expired certificate";
 370                 }
 371
 372                 X509_free(cert);
 373         }
 374
 375  public:
 376         OpenSSLIOHook(IOHookProvider* hookprov, StreamSocket* sock, bool is_outbound, SSL* session, const reference<OpenSSL::Profile>& sslprofile)
 377                 : SSLIOHook(hookprov)
 378                 , sess(session)
 379                 , status(ISSL_NONE)
 380                 , outbound(is_outbound)
 381                 , data_to_write(false)
 382                 , profile(sslprofile)
 383         {
 384                 if (sess == NULL)
 385                         return;
 386                 if (SSL_set_fd(sess, sock->GetFd()) == 0)
 387                         throw ModuleException("Can't set fd with SSL_set_fd: " + ConvToStr(sock->GetFd()));
 388
 389                 sock->AddIOHook(this);
 390                 Handshake(sock);
 391         }
 392
 393         void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE
 394         {
 395                 CloseSession();
 396         }
 397
 398         int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE
 399         {
 400                 if (!sess)
 401                 {
 402                         CloseSession();
 403                         return -1;
 404                 }
 405
 406                 if (status == ISSL_HANDSHAKING)
 407                 {
 408                         // The handshake isn't finished and it wants to read, try to finish it.
 409                         if (!Handshake(user))
 410                         {
 411                                 // Couldn't resume handshake.
 412                                 if (status == ISSL_NONE)
 413                                         return -1;
 414                                 return 0;
 415                         }
 416                 }
 417
 418                 // If we resumed the handshake then this->status will be ISSL_OPEN
 419
 420                 if (status == ISSL_OPEN)
 421                 {
 422                         char* buffer = ServerInstance->GetReadBuffer();
 423                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 424                         int ret = SSL_read(sess, buffer, bufsiz);
 425
 426                         if (ret > 0)
 427                         {
 428                                 recvq.append(buffer, ret);
 429                                 if (data_to_write)
 430                                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE);
 431                                 return 1;
 432                         }
 433                         else if (ret == 0)
 434                         {
 435                                 // Client closed connection.
 436                                 CloseSession();
 437                                 user->SetError("Connection closed");
 438                                 return -1;
 439                         }
 440                         else if (ret < 0)
 441                         {
 442                                 int err = SSL_get_error(sess, ret);
 443
 444                                 if (err == SSL_ERROR_WANT_READ)
 445                                 {
 446                                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ);
 447                                         return 0;
 448                                 }
 449                                 else if (err == SSL_ERROR_WANT_WRITE)
 450                                 {
 451                                         SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 452                                         return 0;
 453                                 }
 454                                 else
 455                                 {
 456                                         CloseSession();
 457                                         return -1;
 458                                 }
 459                         }
 460                 }
 461
 462                 return 0;
 463         }
 464
 465         int OnStreamSocketWrite(StreamSocket* user, std::string& buffer) CXX11_OVERRIDE
 466         {
 467                 if (!sess)
 468                 {
 469                         CloseSession();
 470                         return -1;
 471                 }
 472
 473                 data_to_write = true;
 474
 475                 if (status == ISSL_HANDSHAKING)
 476                 {
 477                         if (!Handshake(user))
 478                         {
 479                                 // Couldn't resume handshake.
 480                                 if (status == ISSL_NONE)
 481                                         return -1;
 482                                 return 0;
 483                         }
 484                 }
 485
 486                 if (status == ISSL_OPEN)
 487                 {
 488                         int ret = SSL_write(sess, buffer.data(), buffer.size());
 489                         if (ret == (int)buffer.length())
 490                         {
 491                                 data_to_write = false;
 492                                 SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 493                                 return 1;
 494                         }
 495                         else if (ret > 0)
 496                         {
 497                                 buffer = buffer.substr(ret);
 498                                 SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 499                                 return 0;
 500                         }
 501                         else if (ret == 0)
 502                         {
 503                                 CloseSession();
 504                                 return -1;
 505                         }
 506                         else if (ret < 0)
 507                         {
 508                                 int err = SSL_get_error(sess, ret);
 509
 510                                 if (err == SSL_ERROR_WANT_WRITE)
 511                                 {
 512                                         SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 513                                         return 0;
 514                                 }
 515                                 else if (err == SSL_ERROR_WANT_READ)
 516                                 {
 517                                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ);
 518                                         return 0;
 519                                 }
 520                                 else
 521                                 {
 522                                         CloseSession();
 523                                         return -1;
 524                                 }
 525                         }
 526                 }
 527                 return 0;
 528         }
 529
 530         void TellCiphersAndFingerprint(LocalUser* user)
 531         {
 532                 if (sess)
 533                 {
 534                         std::string text = "*** You are connected using SSL cipher '" + std::string(SSL_get_cipher(sess)) + "'";
 535                         const std::string& fingerprint = certificate->fingerprint;
 536                         if (!fingerprint.empty())
 537                                 text += " and your SSL fingerprint is " + fingerprint;
 538
 539                         user->WriteNotice(text);
 540                 }
 541         }
 542 };
 543
 544 class OpenSSLIOHookProvider : public refcountbase, public IOHookProvider
 545 {
 546         reference<OpenSSL::Profile> profile;
 547
 548  public:
 549         OpenSSLIOHookProvider(Module* mod, reference<OpenSSL::Profile>& prof)
 550                 : IOHookProvider(mod, "ssl/" + prof->GetName(), IOHookProvider::IOH_SSL)
 551                 , profile(prof)
 552         {
 553                 ServerInstance->Modules->AddService(*this);
 554         }
 555
 556         ~OpenSSLIOHookProvider()
 557         {
 558                 ServerInstance->Modules->DelService(*this);
 559         }
 560
 561         void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE
 562         {
 563                 new OpenSSLIOHook(this, sock, false, profile->CreateServerSession(), profile);
 564         }
 565
 566         void OnConnect(StreamSocket* sock) CXX11_OVERRIDE
 567         {
 568                 new OpenSSLIOHook(this, sock, true, profile->CreateClientSession(), profile);
 569         }
 570 };
 571
 572 class ModuleSSLOpenSSL : public Module
 573 {
 574         typedef std::vector<reference<OpenSSLIOHookProvider> > ProfileList;
 575
 576         ProfileList profiles;
 577
 578         void ReadProfiles()
 579         {
 580                 ProfileList newprofiles;
 581                 ConfigTagList tags = ServerInstance->Config->ConfTags("sslprofile");
 582                 if (tags.first == tags.second)
 583                 {
 584                         // Create a default profile named "openssl"
 585                         const std::string defname = "openssl";
 586                         ConfigTag* tag = ServerInstance->Config->ConfValue(defname);
 587                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "No <sslprofile> tags found, using settings from the <openssl> tag");
 588
 589                         try
 590                         {
 591                                 reference<OpenSSL::Profile> profile(new OpenSSL::Profile(defname, tag));
 592                                 newprofiles.push_back(new OpenSSLIOHookProvider(this, profile));
 593                         }
 594                         catch (OpenSSL::Exception& ex)
 595                         {
 596                                 throw ModuleException("Error while initializing the default SSL profile - " + ex.GetReason());
 597                         }
 598                 }
 599
 600                 for (ConfigIter i = tags.first; i != tags.second; ++i)
 601                 {
 602                         ConfigTag* tag = i->second;
 603                         if (tag->getString("provider") != "openssl")
 604                                 continue;
 605
 606                         std::string name = tag->getString("name");
 607                         if (name.empty())
 608                         {
 609                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Ignoring <sslprofile> tag without name at " + tag->getTagLocation());
 610                                 continue;
 611                         }
 612
 613                         reference<OpenSSL::Profile> profile;
 614                         try
 615                         {
 616                                 profile = new OpenSSL::Profile(name, tag);
 617                         }
 618                         catch (CoreException& ex)
 619                         {
 620                                 throw ModuleException("Error while initializing SSL profile \"" + name + "\" at " + tag->getTagLocation() + " - " + ex.GetReason());
 621                         }
 622
 623                         newprofiles.push_back(new OpenSSLIOHookProvider(this, profile));
 624                 }
 625
 626                 profiles.swap(newprofiles);
 627         }
 628
 629  public:
 630         ModuleSSLOpenSSL()
 631         {
 632                 // Initialize OpenSSL
 633                 SSL_library_init();
 634                 SSL_load_error_strings();
 635         }
 636
 637         void init() CXX11_OVERRIDE
 638         {
 639                 ReadProfiles();
 640         }
 641
 642         void OnModuleRehash(User* user, const std::string &param) CXX11_OVERRIDE
 643         {
 644                 if (param != "ssl")
 645                         return;
 646
 647                 try
 648                 {
 649                         ReadProfiles();
 650                 }
 651                 catch (ModuleException& ex)
 652                 {
 653                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, ex.GetReason() + " Not applying settings.");
 654                 }
 655         }
 656
 657         void OnUserConnect(LocalUser* user) CXX11_OVERRIDE
 658         {
 659                 IOHook* hook = user->eh.GetIOHook();
 660                 if (hook && hook->prov->creator == this)
 661                         static_cast<OpenSSLIOHook*>(hook)->TellCiphersAndFingerprint(user);
 662         }
 663
 664         void OnCleanup(int target_type, void* item) CXX11_OVERRIDE
 665         {
 666                 if (target_type == TYPE_USER)
 667                 {
 668                         LocalUser* user = IS_LOCAL((User*)item);
 669
 670                         if (user && user->eh.GetIOHook() && user->eh.GetIOHook()->prov->creator == this)
 671                         {
 672                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 673                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 674                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 675                         }
 676                 }
 677         }
 678
 679         Version GetVersion() CXX11_OVERRIDE
 680         {
 681                 return Version("Provides SSL support for clients", VF_VENDOR);
 682         }
 683 };
 684
 685 MODULE_INIT(ModuleSSLOpenSSL)