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 <openssl/ssl.h>
  35 #include <openssl/err.h>
  36 #include "ssl.h"
  37
  38 #ifdef _WIN32
  39 # pragma comment(lib, "ssleay32.lib")
  40 # pragma comment(lib, "libeay32.lib")
  41 # undef MAX_DESCRIPTORS
  42 # define MAX_DESCRIPTORS 10000
  43 #endif
  44
  45 /* $ModDesc: Provides SSL support for clients */
  46
  47 /* $LinkerFlags: if("USE_FREEBSD_BASE_SSL") -lssl -lcrypto */
  48 /* $CompileFlags: if(!"USE_FREEBSD_BASE_SSL") pkgconfversion("openssl","0.9.7") pkgconfincludes("openssl","/openssl/ssl.h","") */
  49 /* $LinkerFlags: if(!"USE_FREEBSD_BASE_SSL") rpath("pkg-config --libs openssl") pkgconflibs("openssl","/libssl.so","-lssl -lcrypto -ldl") */
  50
  51 /* $NoPedantic */
  52
  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 error_callback(const char *str, size_t len, void *u);
  64
  65 /** Represents an SSL user's extra data
  66  */
  67 class issl_session
  68 {
  69 public:
  70         SSL* sess;
  71         issl_status status;
  72         reference<ssl_cert> cert;
  73
  74         bool outbound;
  75         bool data_to_write;
  76
  77         issl_session()
  78                 : sess(NULL)
  79                 , status(ISSL_NONE)
  80         {
  81                 outbound = false;
  82                 data_to_write = false;
  83         }
  84 };
  85
  86 static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx)
  87 {
  88         /* XXX: This will allow self signed certificates.
  89          * In the future if we want an option to not allow this,
  90          * we can just return preverify_ok here, and openssl
  91          * will boot off self-signed and invalid peer certs.
  92          */
  93         int ve = X509_STORE_CTX_get_error(ctx);
  94
  95         SelfSigned = (ve == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
  96
  97         return 1;
  98 }
  99
 100 class ModuleSSLOpenSSL : public Module
 101 {
 102         issl_session* sessions;
 103
 104         SSL_CTX* ctx;
 105         SSL_CTX* clictx;
 106
 107         long ctx_options;
 108         long clictx_options;
 109
 110         std::string sslports;
 111         bool use_sha;
 112
 113         ServiceProvider iohook;
 114
 115         static void SetContextOptions(SSL_CTX* ctx, long defoptions, const std::string& ctxname, ConfigTag* tag)
 116         {
 117                 long setoptions = tag->getInt(ctxname + "setoptions");
 118                 // User-friendly config options for setting context options
 119 #ifdef SSL_OP_CIPHER_SERVER_PREFERENCE
 120                 if (tag->getBool("cipherserverpref"))
 121                         setoptions |= SSL_OP_CIPHER_SERVER_PREFERENCE;
 122 #endif
 123 #ifdef SSL_OP_NO_COMPRESSION
 124                 if (!tag->getBool("compression", true))
 125                         setoptions |= SSL_OP_NO_COMPRESSION;
 126 #endif
 127                 if (!tag->getBool("sslv3", true))
 128                         setoptions |= SSL_OP_NO_SSLv3;
 129                 if (!tag->getBool("tlsv1", true))
 130                         setoptions |= SSL_OP_NO_TLSv1;
 131
 132                 long clearoptions = tag->getInt(ctxname + "clearoptions");
 133                 ServerInstance->Logs->Log("m_ssl_openssl", DEBUG, "Setting OpenSSL %s context options, default: %ld set: %ld clear: %ld", ctxname.c_str(), defoptions, setoptions, clearoptions);
 134
 135                 // Clear everything
 136                 SSL_CTX_clear_options(ctx, SSL_CTX_get_options(ctx));
 137
 138                 // Set the default options and what is in the conf
 139                 SSL_CTX_set_options(ctx, defoptions | setoptions);
 140                 long final = SSL_CTX_clear_options(ctx, clearoptions);
 141                 ServerInstance->Logs->Log("m_ssl_openssl", DEFAULT, "OpenSSL %s context options: %ld", ctxname.c_str(), final);
 142         }
 143
 144  public:
 145
 146         ModuleSSLOpenSSL() : iohook(this, "ssl/openssl", SERVICE_IOHOOK)
 147         {
 148                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 149
 150                 /* Global SSL library initialization*/
 151                 SSL_library_init();
 152                 SSL_load_error_strings();
 153
 154                 /* Build our SSL contexts:
 155                  * NOTE: OpenSSL makes us have two contexts, one for servers and one for clients. ICK.
 156                  */
 157                 ctx = SSL_CTX_new( SSLv23_server_method() );
 158                 clictx = SSL_CTX_new( SSLv23_client_method() );
 159
 160                 SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 161                 SSL_CTX_set_mode(clictx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 162
 163                 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 164                 SSL_CTX_set_verify(clictx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 165
 166                 SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF);
 167                 SSL_CTX_set_session_cache_mode(clictx, SSL_SESS_CACHE_OFF);
 168
 169                 long opts = SSL_OP_NO_SSLv2 | SSL_OP_SINGLE_DH_USE;
 170                 // Only turn options on if they exist
 171 #ifdef SSL_OP_SINGLE_ECDH_USE
 172                 opts |= SSL_OP_SINGLE_ECDH_USE;
 173 #endif
 174 #ifdef SSL_OP_NO_TICKET
 175                 opts |= SSL_OP_NO_TICKET;
 176 #endif
 177
 178                 ctx_options = SSL_CTX_set_options(ctx, opts);
 179                 clictx_options = SSL_CTX_set_options(clictx, opts);
 180         }
 181
 182         void init()
 183         {
 184                 // Needs the flag as it ignores a plain /rehash
 185                 OnModuleRehash(NULL,"ssl");
 186                 Implementation eventlist[] = { I_On005Numeric, I_OnRehash, I_OnModuleRehash, I_OnHookIO, I_OnUserConnect };
 187                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 188                 ServerInstance->Modules->AddService(iohook);
 189         }
 190
 191         void OnHookIO(StreamSocket* user, ListenSocket* lsb)
 192         {
 193                 if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "openssl")
 194                 {
 195                         /* Hook the user with our module */
 196                         user->AddIOHook(this);
 197                 }
 198         }
 199
 200         void OnRehash(User* user)
 201         {
 202                 sslports.clear();
 203
 204                 ConfigTag* Conf = ServerInstance->Config->ConfValue("openssl");
 205
 206                 if (Conf->getBool("showports", true))
 207                 {
 208                         sslports = Conf->getString("advertisedports");
 209                         if (!sslports.empty())
 210                                 return;
 211
 212                         for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 213                         {
 214                                 ListenSocket* port = ServerInstance->ports[i];
 215                                 if (port->bind_tag->getString("ssl") != "openssl")
 216                                         continue;
 217
 218                                 const std::string& portid = port->bind_desc;
 219                                 ServerInstance->Logs->Log("m_ssl_openssl", DEFAULT, "m_ssl_openssl.so: Enabling SSL for port %s", portid.c_str());
 220
 221                                 if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
 222                                 {
 223                                         /*
 224                                          * Found an SSL port for clients that is not bound to 127.0.0.1 and handled by us, display
 225                                          * the IP:port in ISUPPORT.
 226                                          *
 227                                          * We used to advertise all ports seperated by a ';' char that matched the above criteria,
 228                                          * but this resulted in too long ISUPPORT lines if there were lots of ports to be displayed.
 229                                          * To solve this by default we now only display the first IP:port found and let the user
 230                                          * configure the exact value for the 005 token, if necessary.
 231                                          */
 232                                         sslports = portid;
 233                                         break;
 234                                 }
 235                         }
 236                 }
 237         }
 238
 239         void OnModuleRehash(User* user, const std::string &param)
 240         {
 241                 if (param != "ssl")
 242                         return;
 243
 244                 std::string keyfile;
 245                 std::string certfile;
 246                 std::string cafile;
 247                 std::string dhfile;
 248                 OnRehash(user);
 249
 250                 ConfigTag* conf = ServerInstance->Config->ConfValue("openssl");
 251
 252                 cafile   = conf->getString("cafile", CONFIG_PATH "/ca.pem");
 253                 certfile = conf->getString("certfile", CONFIG_PATH "/cert.pem");
 254                 keyfile  = conf->getString("keyfile", CONFIG_PATH "/key.pem");
 255                 dhfile   = conf->getString("dhfile", CONFIG_PATH "/dhparams.pem");
 256                 std::string hash = conf->getString("hash", "md5");
 257                 if (hash != "sha1" && hash != "md5")
 258                         throw ModuleException("Unknown hash type " + hash);
 259                 use_sha = (hash == "sha1");
 260
 261                 if (conf->getBool("customcontextoptions"))
 262                 {
 263                         SetContextOptions(ctx, ctx_options, "server", conf);
 264                         SetContextOptions(clictx, clictx_options, "client", conf);
 265                 }
 266
 267                 std::string ciphers = conf->getString("ciphers", "");
 268
 269                 if (!ciphers.empty())
 270                 {
 271                         ERR_clear_error();
 272                         if ((!SSL_CTX_set_cipher_list(ctx, ciphers.c_str())) || (!SSL_CTX_set_cipher_list(clictx, ciphers.c_str())))
 273                         {
 274                                 ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't set cipher list to %s.", ciphers.c_str());
 275                                 ERR_print_errors_cb(error_callback, this);
 276                         }
 277                 }
 278
 279                 /* Load our keys and certificates
 280                  * NOTE: OpenSSL's error logging API sucks, don't blame us for this clusterfuck.
 281                  */
 282                 ERR_clear_error();
 283                 if ((!SSL_CTX_use_certificate_chain_file(ctx, certfile.c_str())) || (!SSL_CTX_use_certificate_chain_file(clictx, certfile.c_str())))
 284                 {
 285                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't read certificate file %s. %s", certfile.c_str(), strerror(errno));
 286                         ERR_print_errors_cb(error_callback, this);
 287                 }
 288
 289                 ERR_clear_error();
 290                 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)))
 291                 {
 292                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't read key file %s. %s", keyfile.c_str(), strerror(errno));
 293                         ERR_print_errors_cb(error_callback, this);
 294                 }
 295
 296                 /* Load the CAs we trust*/
 297                 ERR_clear_error();
 298                 if (((!SSL_CTX_load_verify_locations(ctx, cafile.c_str(), 0))) || (!SSL_CTX_load_verify_locations(clictx, cafile.c_str(), 0)))
 299                 {
 300                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: 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", cafile.c_str(), strerror(errno));
 301                         ERR_print_errors_cb(error_callback, this);
 302                 }
 303
 304 #ifdef _WIN32
 305                 BIO* dhpfile = BIO_new_file(dhfile.c_str(), "r");
 306 #else
 307                 FILE* dhpfile = fopen(dhfile.c_str(), "r");
 308 #endif
 309                 DH* ret;
 310
 311                 if (dhpfile == NULL)
 312                 {
 313                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so Couldn't open DH file %s: %s", dhfile.c_str(), strerror(errno));
 314                         throw ModuleException("Couldn't open DH file " + dhfile + ": " + strerror(errno));
 315                 }
 316                 else
 317                 {
 318 #ifdef _WIN32
 319                         ret = PEM_read_bio_DHparams(dhpfile, NULL, NULL, NULL);
 320                         BIO_free(dhpfile);
 321 #else
 322                         ret = PEM_read_DHparams(dhpfile, NULL, NULL, NULL);
 323 #endif
 324
 325                         ERR_clear_error();
 326                         if ((SSL_CTX_set_tmp_dh(ctx, ret) < 0) || (SSL_CTX_set_tmp_dh(clictx, ret) < 0))
 327                         {
 328                                 ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Couldn't set DH parameters %s. SSL errors follow:", dhfile.c_str());
 329                                 ERR_print_errors_cb(error_callback, this);
 330                         }
 331                         DH_free(ret);
 332                 }
 333
 334 #ifndef _WIN32
 335                 fclose(dhpfile);
 336 #endif
 337         }
 338
 339         void On005Numeric(std::string &output)
 340         {
 341                 if (!sslports.empty())
 342                         output.append(" SSL=" + sslports);
 343         }
 344
 345         ~ModuleSSLOpenSSL()
 346         {
 347                 SSL_CTX_free(ctx);
 348                 SSL_CTX_free(clictx);
 349                 delete[] sessions;
 350         }
 351
 352         void OnUserConnect(LocalUser* user)
 353         {
 354                 if (user->eh.GetIOHook() == this)
 355                 {
 356                         if (sessions[user->eh.GetFd()].sess)
 357                         {
 358                                 if (!sessions[user->eh.GetFd()].cert->fingerprint.empty())
 359                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\""
 360                                                 " and your SSL fingerprint is %s", user->nick.c_str(), SSL_get_cipher(sessions[user->eh.GetFd()].sess), sessions[user->eh.GetFd()].cert->fingerprint.c_str());
 361                                 else
 362                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), SSL_get_cipher(sessions[user->eh.GetFd()].sess));
 363                         }
 364                 }
 365         }
 366
 367         void OnCleanup(int target_type, void* item)
 368         {
 369                 if (target_type == TYPE_USER)
 370                 {
 371                         LocalUser* user = IS_LOCAL((User*)item);
 372
 373                         if (user && user->eh.GetIOHook() == this)
 374                         {
 375                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 376                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 377                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 378                         }
 379                 }
 380         }
 381
 382         Version GetVersion()
 383         {
 384                 return Version("Provides SSL support for clients", VF_VENDOR);
 385         }
 386
 387         void OnRequest(Request& request)
 388         {
 389                 if (strcmp("GET_SSL_CERT", request.id) == 0)
 390                 {
 391                         SocketCertificateRequest& req = static_cast<SocketCertificateRequest&>(request);
 392                         int fd = req.sock->GetFd();
 393                         issl_session* session = &sessions[fd];
 394
 395                         req.cert = session->cert;
 396                 }
 397                 else if (!strcmp("GET_RAW_SSL_SESSION", request.id))
 398                 {
 399                         SSLRawSessionRequest& req = static_cast<SSLRawSessionRequest&>(request);
 400                         if ((req.fd >= 0) && (req.fd < ServerInstance->SE->GetMaxFds()))
 401                                 req.data = reinterpret_cast<void*>(sessions[req.fd].sess);
 402                 }
 403         }
 404
 405         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 406         {
 407                 int fd = user->GetFd();
 408
 409                 issl_session* session = &sessions[fd];
 410
 411                 session->sess = SSL_new(ctx);
 412                 session->status = ISSL_NONE;
 413                 session->outbound = false;
 414                 session->data_to_write = false;
 415
 416                 if (session->sess == NULL)
 417                         return;
 418
 419                 if (SSL_set_fd(session->sess, fd) == 0)
 420                 {
 421                         ServerInstance->Logs->Log("m_ssl_openssl",DEBUG,"BUG: Can't set fd with SSL_set_fd: %d", fd);
 422                         return;
 423                 }
 424
 425                 Handshake(user, session);
 426         }
 427
 428         void OnStreamSocketConnect(StreamSocket* user)
 429         {
 430                 int fd = user->GetFd();
 431                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 432                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() -1))
 433                         return;
 434
 435                 issl_session* session = &sessions[fd];
 436
 437                 session->sess = SSL_new(clictx);
 438                 session->status = ISSL_NONE;
 439                 session->outbound = true;
 440                 session->data_to_write = false;
 441
 442                 if (session->sess == NULL)
 443                         return;
 444
 445                 if (SSL_set_fd(session->sess, fd) == 0)
 446                 {
 447                         ServerInstance->Logs->Log("m_ssl_openssl",DEBUG,"BUG: Can't set fd with SSL_set_fd: %d", fd);
 448                         return;
 449                 }
 450
 451                 Handshake(user, session);
 452         }
 453
 454         void OnStreamSocketClose(StreamSocket* user)
 455         {
 456                 int fd = user->GetFd();
 457                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 458                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 459                         return;
 460
 461                 CloseSession(&sessions[fd]);
 462         }
 463
 464         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 465         {
 466                 int fd = user->GetFd();
 467                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 468                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 469                         return -1;
 470
 471                 issl_session* session = &sessions[fd];
 472
 473                 if (!session->sess)
 474                 {
 475                         CloseSession(session);
 476                         return -1;
 477                 }
 478
 479                 if (session->status == ISSL_HANDSHAKING)
 480                 {
 481                         // The handshake isn't finished and it wants to read, try to finish it.
 482                         if (!Handshake(user, session))
 483                         {
 484                                 // Couldn't resume handshake.
 485                                 if (session->status == ISSL_NONE)
 486                                         return -1;
 487                                 return 0;
 488                         }
 489                 }
 490
 491                 // If we resumed the handshake then session->status will be ISSL_OPEN
 492
 493                 if (session->status == ISSL_OPEN)
 494                 {
 495                         ERR_clear_error();
 496                         char* buffer = ServerInstance->GetReadBuffer();
 497                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 498                         int ret = SSL_read(session->sess, buffer, bufsiz);
 499
 500                         if (ret > 0)
 501                         {
 502                                 recvq.append(buffer, ret);
 503                                 if (session->data_to_write)
 504                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE);
 505                                 return 1;
 506                         }
 507                         else if (ret == 0)
 508                         {
 509                                 // Client closed connection.
 510                                 CloseSession(session);
 511                                 user->SetError("Connection closed");
 512                                 return -1;
 513                         }
 514                         else 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);
 521                                         return 0;
 522                                 }
 523                                 else if (err == SSL_ERROR_WANT_WRITE)
 524                                 {
 525                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 526                                         return 0;
 527                                 }
 528                                 else
 529                                 {
 530                                         CloseSession(session);
 531                                         return -1;
 532                                 }
 533                         }
 534                 }
 535
 536                 return 0;
 537         }
 538
 539         int OnStreamSocketWrite(StreamSocket* user, std::string& buffer)
 540         {
 541                 int fd = user->GetFd();
 542
 543                 issl_session* session = &sessions[fd];
 544
 545                 if (!session->sess)
 546                 {
 547                         CloseSession(session);
 548                         return -1;
 549                 }
 550
 551                 session->data_to_write = true;
 552
 553                 if (session->status == ISSL_HANDSHAKING)
 554                 {
 555                         if (!Handshake(user, session))
 556                         {
 557                                 // Couldn't resume handshake.
 558                                 if (session->status == ISSL_NONE)
 559                                         return -1;
 560                                 return 0;
 561                         }
 562                 }
 563
 564                 if (session->status == ISSL_OPEN)
 565                 {
 566                         ERR_clear_error();
 567                         int ret = SSL_write(session->sess, buffer.data(), buffer.size());
 568                         if (ret == (int)buffer.length())
 569                         {
 570                                 session->data_to_write = false;
 571                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 572                                 return 1;
 573                         }
 574                         else if (ret > 0)
 575                         {
 576                                 buffer = buffer.substr(ret);
 577                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 578                                 return 0;
 579                         }
 580                         else if (ret == 0)
 581                         {
 582                                 CloseSession(session);
 583                                 return -1;
 584                         }
 585                         else if (ret < 0)
 586                         {
 587                                 int err = SSL_get_error(session->sess, ret);
 588
 589                                 if (err == SSL_ERROR_WANT_WRITE)
 590                                 {
 591                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 592                                         return 0;
 593                                 }
 594                                 else if (err == SSL_ERROR_WANT_READ)
 595                                 {
 596                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ);
 597                                         return 0;
 598                                 }
 599                                 else
 600                                 {
 601                                         CloseSession(session);
 602                                         return -1;
 603                                 }
 604                         }
 605                 }
 606                 return 0;
 607         }
 608
 609         bool Handshake(StreamSocket* user, issl_session* session)
 610         {
 611                 int ret;
 612
 613                 ERR_clear_error();
 614                 if (session->outbound)
 615                         ret = SSL_connect(session->sess);
 616                 else
 617                         ret = SSL_accept(session->sess);
 618
 619                 if (ret < 0)
 620                 {
 621                         int err = SSL_get_error(session->sess, ret);
 622
 623                         if (err == SSL_ERROR_WANT_READ)
 624                         {
 625                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 626                                 session->status = ISSL_HANDSHAKING;
 627                                 return true;
 628                         }
 629                         else if (err == SSL_ERROR_WANT_WRITE)
 630                         {
 631                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 632                                 session->status = ISSL_HANDSHAKING;
 633                                 return true;
 634                         }
 635                         else
 636                         {
 637                                 CloseSession(session);
 638                         }
 639
 640                         return false;
 641                 }
 642                 else if (ret > 0)
 643                 {
 644                         // Handshake complete.
 645                         VerifyCertificate(session, user);
 646
 647                         session->status = ISSL_OPEN;
 648
 649                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 650
 651                         return true;
 652                 }
 653                 else if (ret == 0)
 654                 {
 655                         CloseSession(session);
 656                         return false;
 657                 }
 658
 659                 return true;
 660         }
 661
 662         void CloseSession(issl_session* session)
 663         {
 664                 if (session->sess)
 665                 {
 666                         SSL_shutdown(session->sess);
 667                         SSL_free(session->sess);
 668                 }
 669
 670                 session->sess = NULL;
 671                 session->status = ISSL_NONE;
 672                 session->cert = NULL;
 673         }
 674
 675         void VerifyCertificate(issl_session* session, StreamSocket* user)
 676         {
 677                 if (!session->sess || !user)
 678                         return;
 679
 680                 X509* cert;
 681                 ssl_cert* certinfo = new ssl_cert;
 682                 session->cert = certinfo;
 683                 unsigned int n;
 684                 unsigned char md[EVP_MAX_MD_SIZE];
 685                 const EVP_MD *digest = use_sha ? EVP_sha1() : EVP_md5();
 686
 687                 cert = SSL_get_peer_certificate((SSL*)session->sess);
 688
 689                 if (!cert)
 690                 {
 691                         certinfo->error = "Could not get peer certificate: "+std::string(get_error());
 692                         return;
 693                 }
 694
 695                 certinfo->invalid = (SSL_get_verify_result(session->sess) != X509_V_OK);
 696
 697                 if (!SelfSigned)
 698                 {
 699                         certinfo->unknownsigner = false;
 700                         certinfo->trusted = true;
 701                 }
 702                 else
 703                 {
 704                         certinfo->unknownsigner = true;
 705                         certinfo->trusted = false;
 706                 }
 707
 708                 char buf[512];
 709                 X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
 710                 certinfo->dn = buf;
 711                 // Make sure there are no chars in the string that we consider invalid
 712                 if (certinfo->dn.find_first_of("\r\n") != std::string::npos)
 713                         certinfo->dn.clear();
 714
 715                 X509_NAME_oneline(X509_get_issuer_name(cert), buf, sizeof(buf));
 716                 certinfo->issuer = buf;
 717                 if (certinfo->issuer.find_first_of("\r\n") != std::string::npos)
 718                         certinfo->issuer.clear();
 719
 720                 if (!X509_digest(cert, digest, md, &n))
 721                 {
 722                         certinfo->error = "Out of memory generating fingerprint";
 723                 }
 724                 else
 725                 {
 726                         certinfo->fingerprint = irc::hex(md, n);
 727                 }
 728
 729                 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))
 730                 {
 731                         certinfo->error = "Not activated, or expired certificate";
 732                 }
 733
 734                 X509_free(cert);
 735         }
 736 };
 737
 738 static int error_callback(const char *str, size_t len, void *u)
 739 {
 740         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "SSL error: " + std::string(str, len - 1));
 741
 742         //
 743         // XXX: Remove this line, it causes valgrind warnings...
 744         //
 745         // MD_update(&m, buf, j);
 746         //
 747         //
 748         // ... ONLY JOKING! :-)
 749         //
 750
 751         return 0;
 752 }
 753
 754 MODULE_INIT(ModuleSSLOpenSSL)