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         {
  79                 outbound = false;
  80                 data_to_write = false;
  81         }
  82 };
  83
  84 static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx)
  85 {
  86         /* XXX: This will allow self signed certificates.
  87          * In the future if we want an option to not allow this,
  88          * we can just return preverify_ok here, and openssl
  89          * will boot off self-signed and invalid peer certs.
  90          */
  91         int ve = X509_STORE_CTX_get_error(ctx);
  92
  93         SelfSigned = (ve == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
  94
  95         return 1;
  96 }
  97
  98 class ModuleSSLOpenSSL : public Module
  99 {
 100         issl_session* sessions;
 101
 102         SSL_CTX* ctx;
 103         SSL_CTX* clictx;
 104
 105         long ctx_options;
 106         long clictx_options;
 107
 108         std::string sslports;
 109         bool use_sha;
 110
 111         ServiceProvider iohook;
 112
 113         static void SetContextOptions(SSL_CTX* ctx, long defoptions, const std::string& ctxname, ConfigTag* tag)
 114         {
 115                 long setoptions = tag->getInt(ctxname + "setoptions");
 116                 // User-friendly config options for setting context options
 117 #ifdef SSL_OP_CIPHER_SERVER_PREFERENCE
 118                 if (tag->getBool("cipherserverpref"))
 119                         setoptions |= SSL_OP_CIPHER_SERVER_PREFERENCE;
 120 #endif
 121 #ifdef SSL_OP_NO_COMPRESSION
 122                 if (!tag->getBool("compression", true))
 123                         setoptions |= SSL_OP_NO_COMPRESSION;
 124 #endif
 125                 if (!tag->getBool("sslv3", true))
 126                         setoptions |= SSL_OP_NO_SSLv3;
 127                 if (!tag->getBool("tlsv1", true))
 128                         setoptions |= SSL_OP_NO_TLSv1;
 129
 130                 long clearoptions = tag->getInt(ctxname + "clearoptions");
 131                 ServerInstance->Logs->Log("m_ssl_openssl", DEBUG, "Setting OpenSSL %s context options, default: %ld set: %ld clear: %ld", ctxname.c_str(), defoptions, clearoptions, setoptions);
 132
 133                 // Clear everything
 134                 SSL_CTX_clear_options(ctx, SSL_CTX_get_options(ctx));
 135
 136                 // Set the default options and what is in the conf
 137                 SSL_CTX_set_options(ctx, defoptions | setoptions);
 138                 long final = SSL_CTX_clear_options(ctx, clearoptions);
 139                 ServerInstance->Logs->Log("m_ssl_openssl", DEFAULT, "OpenSSL %s context options: %ld", ctxname.c_str(), final);
 140         }
 141
 142  public:
 143
 144         ModuleSSLOpenSSL() : iohook(this, "ssl/openssl", SERVICE_IOHOOK)
 145         {
 146                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 147
 148                 /* Global SSL library initialization*/
 149                 SSL_library_init();
 150                 SSL_load_error_strings();
 151
 152                 /* Build our SSL contexts:
 153                  * NOTE: OpenSSL makes us have two contexts, one for servers and one for clients. ICK.
 154                  */
 155                 ctx = SSL_CTX_new( SSLv23_server_method() );
 156                 clictx = SSL_CTX_new( SSLv23_client_method() );
 157
 158                 SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 159                 SSL_CTX_set_mode(clictx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 160
 161                 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 162                 SSL_CTX_set_verify(clictx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 163
 164                 SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF);
 165                 SSL_CTX_set_session_cache_mode(clictx, SSL_SESS_CACHE_OFF);
 166
 167                 long opts = SSL_OP_NO_SSLv2 | SSL_OP_SINGLE_DH_USE;
 168                 // Only turn options on if they exist
 169 #ifdef SSL_OP_SINGLE_ECDH_USE
 170                 opts |= SSL_OP_SINGLE_ECDH_USE;
 171 #endif
 172 #ifdef SSL_OP_NO_TICKET
 173                 opts |= SSL_OP_NO_TICKET;
 174 #endif
 175
 176                 ctx_options = SSL_CTX_set_options(ctx, opts);
 177                 clictx_options = SSL_CTX_set_options(clictx, opts);
 178         }
 179
 180         void init()
 181         {
 182                 // Needs the flag as it ignores a plain /rehash
 183                 OnModuleRehash(NULL,"ssl");
 184                 Implementation eventlist[] = { I_On005Numeric, I_OnRehash, I_OnModuleRehash, I_OnHookIO, I_OnUserConnect };
 185                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 186                 ServerInstance->Modules->AddService(iohook);
 187         }
 188
 189         void OnHookIO(StreamSocket* user, ListenSocket* lsb)
 190         {
 191                 if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "openssl")
 192                 {
 193                         /* Hook the user with our module */
 194                         user->AddIOHook(this);
 195                 }
 196         }
 197
 198         void OnRehash(User* user)
 199         {
 200                 sslports.clear();
 201
 202                 ConfigTag* Conf = ServerInstance->Config->ConfValue("openssl");
 203
 204                 if (Conf->getBool("showports", true))
 205                 {
 206                         sslports = Conf->getString("advertisedports");
 207                         if (!sslports.empty())
 208                                 return;
 209
 210                         for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 211                         {
 212                                 ListenSocket* port = ServerInstance->ports[i];
 213                                 if (port->bind_tag->getString("ssl") != "openssl")
 214                                         continue;
 215
 216                                 const std::string& portid = port->bind_desc;
 217                                 ServerInstance->Logs->Log("m_ssl_openssl", DEFAULT, "m_ssl_openssl.so: Enabling SSL for port %s", portid.c_str());
 218
 219                                 if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
 220                                 {
 221                                         /*
 222                                          * Found an SSL port for clients that is not bound to 127.0.0.1 and handled by us, display
 223                                          * the IP:port in ISUPPORT.
 224                                          *
 225                                          * We used to advertise all ports seperated by a ';' char that matched the above criteria,
 226                                          * but this resulted in too long ISUPPORT lines if there were lots of ports to be displayed.
 227                                          * To solve this by default we now only display the first IP:port found and let the user
 228                                          * configure the exact value for the 005 token, if necessary.
 229                                          */
 230                                         sslports = portid;
 231                                         break;
 232                                 }
 233                         }
 234                 }
 235         }
 236
 237         void OnModuleRehash(User* user, const std::string &param)
 238         {
 239                 if (param != "ssl")
 240                         return;
 241
 242                 std::string keyfile;
 243                 std::string certfile;
 244                 std::string cafile;
 245                 std::string dhfile;
 246                 OnRehash(user);
 247
 248                 ConfigTag* conf = ServerInstance->Config->ConfValue("openssl");
 249
 250                 cafile   = conf->getString("cafile", CONFIG_PATH "/ca.pem");
 251                 certfile = conf->getString("certfile", CONFIG_PATH "/cert.pem");
 252                 keyfile  = conf->getString("keyfile", CONFIG_PATH "/key.pem");
 253                 dhfile   = conf->getString("dhfile", CONFIG_PATH "/dhparams.pem");
 254                 std::string hash = conf->getString("hash", "md5");
 255                 if (hash != "sha1" && hash != "md5")
 256                         throw ModuleException("Unknown hash type " + hash);
 257                 use_sha = (hash == "sha1");
 258
 259                 if (conf->getBool("customcontextoptions"))
 260                 {
 261                         SetContextOptions(ctx, ctx_options, "server", conf);
 262                         SetContextOptions(clictx, clictx_options, "client", conf);
 263                 }
 264
 265                 std::string ciphers = conf->getString("ciphers", "");
 266
 267                 if (!ciphers.empty())
 268                 {
 269                         ERR_clear_error();
 270                         if ((!SSL_CTX_set_cipher_list(ctx, ciphers.c_str())) || (!SSL_CTX_set_cipher_list(clictx, ciphers.c_str())))
 271                         {
 272                                 ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't set cipher list to %s.", ciphers.c_str());
 273                                 ERR_print_errors_cb(error_callback, this);
 274                         }
 275                 }
 276
 277                 /* Load our keys and certificates
 278                  * NOTE: OpenSSL's error logging API sucks, don't blame us for this clusterfuck.
 279                  */
 280                 ERR_clear_error();
 281                 if ((!SSL_CTX_use_certificate_chain_file(ctx, certfile.c_str())) || (!SSL_CTX_use_certificate_chain_file(clictx, certfile.c_str())))
 282                 {
 283                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't read certificate file %s. %s", certfile.c_str(), strerror(errno));
 284                         ERR_print_errors_cb(error_callback, this);
 285                 }
 286
 287                 ERR_clear_error();
 288                 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)))
 289                 {
 290                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Can't read key file %s. %s", keyfile.c_str(), strerror(errno));
 291                         ERR_print_errors_cb(error_callback, this);
 292                 }
 293
 294                 /* Load the CAs we trust*/
 295                 ERR_clear_error();
 296                 if (((!SSL_CTX_load_verify_locations(ctx, cafile.c_str(), 0))) || (!SSL_CTX_load_verify_locations(clictx, cafile.c_str(), 0)))
 297                 {
 298                         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));
 299                         ERR_print_errors_cb(error_callback, this);
 300                 }
 301
 302 #ifdef _WIN32
 303                 BIO* dhpfile = BIO_new_file(dhfile.c_str(), "r");
 304 #else
 305                 FILE* dhpfile = fopen(dhfile.c_str(), "r");
 306 #endif
 307                 DH* ret;
 308
 309                 if (dhpfile == NULL)
 310                 {
 311                         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so Couldn't open DH file %s: %s", dhfile.c_str(), strerror(errno));
 312                         throw ModuleException("Couldn't open DH file " + dhfile + ": " + strerror(errno));
 313                 }
 314                 else
 315                 {
 316 #ifdef _WIN32
 317                         ret = PEM_read_bio_DHparams(dhpfile, NULL, NULL, NULL);
 318                         BIO_free(dhpfile);
 319 #else
 320                         ret = PEM_read_DHparams(dhpfile, NULL, NULL, NULL);
 321 #endif
 322
 323                         ERR_clear_error();
 324                         if ((SSL_CTX_set_tmp_dh(ctx, ret) < 0) || (SSL_CTX_set_tmp_dh(clictx, ret) < 0))
 325                         {
 326                                 ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "m_ssl_openssl.so: Couldn't set DH parameters %s. SSL errors follow:", dhfile.c_str());
 327                                 ERR_print_errors_cb(error_callback, this);
 328                         }
 329                         DH_free(ret);
 330                 }
 331
 332 #ifndef _WIN32
 333                 fclose(dhpfile);
 334 #endif
 335         }
 336
 337         void On005Numeric(std::string &output)
 338         {
 339                 if (!sslports.empty())
 340                         output.append(" SSL=" + sslports);
 341         }
 342
 343         ~ModuleSSLOpenSSL()
 344         {
 345                 SSL_CTX_free(ctx);
 346                 SSL_CTX_free(clictx);
 347                 delete[] sessions;
 348         }
 349
 350         void OnUserConnect(LocalUser* user)
 351         {
 352                 if (user->eh.GetIOHook() == this)
 353                 {
 354                         if (sessions[user->eh.GetFd()].sess)
 355                         {
 356                                 if (!sessions[user->eh.GetFd()].cert->fingerprint.empty())
 357                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\""
 358                                                 " 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());
 359                                 else
 360                                         user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), SSL_get_cipher(sessions[user->eh.GetFd()].sess));
 361                         }
 362                 }
 363         }
 364
 365         void OnCleanup(int target_type, void* item)
 366         {
 367                 if (target_type == TYPE_USER)
 368                 {
 369                         LocalUser* user = IS_LOCAL((User*)item);
 370
 371                         if (user && user->eh.GetIOHook() == this)
 372                         {
 373                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 374                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 375                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 376                         }
 377                 }
 378         }
 379
 380         Version GetVersion()
 381         {
 382                 return Version("Provides SSL support for clients", VF_VENDOR);
 383         }
 384
 385         void OnRequest(Request& request)
 386         {
 387                 if (strcmp("GET_SSL_CERT", request.id) == 0)
 388                 {
 389                         SocketCertificateRequest& req = static_cast<SocketCertificateRequest&>(request);
 390                         int fd = req.sock->GetFd();
 391                         issl_session* session = &sessions[fd];
 392
 393                         req.cert = session->cert;
 394                 }
 395         }
 396
 397         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 398         {
 399                 int fd = user->GetFd();
 400
 401                 issl_session* session = &sessions[fd];
 402
 403                 session->sess = SSL_new(ctx);
 404                 session->status = ISSL_NONE;
 405                 session->outbound = false;
 406                 session->cert = NULL;
 407
 408                 if (session->sess == NULL)
 409                         return;
 410
 411                 if (SSL_set_fd(session->sess, fd) == 0)
 412                 {
 413                         ServerInstance->Logs->Log("m_ssl_openssl",DEBUG,"BUG: Can't set fd with SSL_set_fd: %d", fd);
 414                         return;
 415                 }
 416
 417                 Handshake(user, session);
 418         }
 419
 420         void OnStreamSocketConnect(StreamSocket* user)
 421         {
 422                 int fd = user->GetFd();
 423                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 424                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() -1))
 425                         return;
 426
 427                 issl_session* session = &sessions[fd];
 428
 429                 session->sess = SSL_new(clictx);
 430                 session->status = ISSL_NONE;
 431                 session->outbound = true;
 432
 433                 if (session->sess == NULL)
 434                         return;
 435
 436                 if (SSL_set_fd(session->sess, fd) == 0)
 437                 {
 438                         ServerInstance->Logs->Log("m_ssl_openssl",DEBUG,"BUG: Can't set fd with SSL_set_fd: %d", fd);
 439                         return;
 440                 }
 441
 442                 Handshake(user, session);
 443         }
 444
 445         void OnStreamSocketClose(StreamSocket* user)
 446         {
 447                 int fd = user->GetFd();
 448                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 449                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 450                         return;
 451
 452                 CloseSession(&sessions[fd]);
 453         }
 454
 455         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 456         {
 457                 int fd = user->GetFd();
 458                 /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
 459                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 460                         return -1;
 461
 462                 issl_session* session = &sessions[fd];
 463
 464                 if (!session->sess)
 465                 {
 466                         CloseSession(session);
 467                         return -1;
 468                 }
 469
 470                 if (session->status == ISSL_HANDSHAKING)
 471                 {
 472                         // The handshake isn't finished and it wants to read, try to finish it.
 473                         if (!Handshake(user, session))
 474                         {
 475                                 // Couldn't resume handshake.
 476                                 if (session->status == ISSL_NONE)
 477                                         return -1;
 478                                 return 0;
 479                         }
 480                 }
 481
 482                 // If we resumed the handshake then session->status will be ISSL_OPEN
 483
 484                 if (session->status == ISSL_OPEN)
 485                 {
 486                         ERR_clear_error();
 487                         char* buffer = ServerInstance->GetReadBuffer();
 488                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 489                         int ret = SSL_read(session->sess, buffer, bufsiz);
 490
 491                         if (ret > 0)
 492                         {
 493                                 recvq.append(buffer, ret);
 494                                 if (session->data_to_write)
 495                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE);
 496                                 return 1;
 497                         }
 498                         else if (ret == 0)
 499                         {
 500                                 // Client closed connection.
 501                                 CloseSession(session);
 502                                 user->SetError("Connection closed");
 503                                 return -1;
 504                         }
 505                         else if (ret < 0)
 506                         {
 507                                 int err = SSL_get_error(session->sess, ret);
 508
 509                                 if (err == SSL_ERROR_WANT_READ)
 510                                 {
 511                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ);
 512                                         return 0;
 513                                 }
 514                                 else if (err == SSL_ERROR_WANT_WRITE)
 515                                 {
 516                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 517                                         return 0;
 518                                 }
 519                                 else
 520                                 {
 521                                         CloseSession(session);
 522                                         return -1;
 523                                 }
 524                         }
 525                 }
 526
 527                 return 0;
 528         }
 529
 530         int OnStreamSocketWrite(StreamSocket* user, std::string& buffer)
 531         {
 532                 int fd = user->GetFd();
 533
 534                 issl_session* session = &sessions[fd];
 535
 536                 if (!session->sess)
 537                 {
 538                         CloseSession(session);
 539                         return -1;
 540                 }
 541
 542                 session->data_to_write = true;
 543
 544                 if (session->status == ISSL_HANDSHAKING)
 545                 {
 546                         if (!Handshake(user, session))
 547                         {
 548                                 // Couldn't resume handshake.
 549                                 if (session->status == ISSL_NONE)
 550                                         return -1;
 551                                 return 0;
 552                         }
 553                 }
 554
 555                 if (session->status == ISSL_OPEN)
 556                 {
 557                         ERR_clear_error();
 558                         int ret = SSL_write(session->sess, buffer.data(), buffer.size());
 559                         if (ret == (int)buffer.length())
 560                         {
 561                                 session->data_to_write = false;
 562                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 563                                 return 1;
 564                         }
 565                         else if (ret > 0)
 566                         {
 567                                 buffer = buffer.substr(ret);
 568                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 569                                 return 0;
 570                         }
 571                         else if (ret == 0)
 572                         {
 573                                 CloseSession(session);
 574                                 return -1;
 575                         }
 576                         else if (ret < 0)
 577                         {
 578                                 int err = SSL_get_error(session->sess, ret);
 579
 580                                 if (err == SSL_ERROR_WANT_WRITE)
 581                                 {
 582                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 583                                         return 0;
 584                                 }
 585                                 else if (err == SSL_ERROR_WANT_READ)
 586                                 {
 587                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ);
 588                                         return 0;
 589                                 }
 590                                 else
 591                                 {
 592                                         CloseSession(session);
 593                                         return -1;
 594                                 }
 595                         }
 596                 }
 597                 return 0;
 598         }
 599
 600         bool Handshake(StreamSocket* user, issl_session* session)
 601         {
 602                 int ret;
 603
 604                 ERR_clear_error();
 605                 if (session->outbound)
 606                         ret = SSL_connect(session->sess);
 607                 else
 608                         ret = SSL_accept(session->sess);
 609
 610                 if (ret < 0)
 611                 {
 612                         int err = SSL_get_error(session->sess, ret);
 613
 614                         if (err == SSL_ERROR_WANT_READ)
 615                         {
 616                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 617                                 session->status = ISSL_HANDSHAKING;
 618                                 return true;
 619                         }
 620                         else if (err == SSL_ERROR_WANT_WRITE)
 621                         {
 622                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 623                                 session->status = ISSL_HANDSHAKING;
 624                                 return true;
 625                         }
 626                         else
 627                         {
 628                                 CloseSession(session);
 629                         }
 630
 631                         return false;
 632                 }
 633                 else if (ret > 0)
 634                 {
 635                         // Handshake complete.
 636                         VerifyCertificate(session, user);
 637
 638                         session->status = ISSL_OPEN;
 639
 640                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 641
 642                         return true;
 643                 }
 644                 else if (ret == 0)
 645                 {
 646                         CloseSession(session);
 647                         return false;
 648                 }
 649
 650                 return true;
 651         }
 652
 653         void CloseSession(issl_session* session)
 654         {
 655                 if (session->sess)
 656                 {
 657                         SSL_shutdown(session->sess);
 658                         SSL_free(session->sess);
 659                 }
 660
 661                 session->sess = NULL;
 662                 session->status = ISSL_NONE;
 663         }
 664
 665         void VerifyCertificate(issl_session* session, StreamSocket* user)
 666         {
 667                 if (!session->sess || !user)
 668                         return;
 669
 670                 X509* cert;
 671                 ssl_cert* certinfo = new ssl_cert;
 672                 session->cert = certinfo;
 673                 unsigned int n;
 674                 unsigned char md[EVP_MAX_MD_SIZE];
 675                 const EVP_MD *digest = use_sha ? EVP_sha1() : EVP_md5();
 676
 677                 cert = SSL_get_peer_certificate((SSL*)session->sess);
 678
 679                 if (!cert)
 680                 {
 681                         certinfo->error = "Could not get peer certificate: "+std::string(get_error());
 682                         return;
 683                 }
 684
 685                 certinfo->invalid = (SSL_get_verify_result(session->sess) != X509_V_OK);
 686
 687                 if (!SelfSigned)
 688                 {
 689                         certinfo->unknownsigner = false;
 690                         certinfo->trusted = true;
 691                 }
 692                 else
 693                 {
 694                         certinfo->unknownsigner = true;
 695                         certinfo->trusted = false;
 696                 }
 697
 698                 char buf[512];
 699                 X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
 700                 certinfo->dn = buf;
 701                 // Make sure there are no chars in the string that we consider invalid
 702                 if (certinfo->dn.find_first_of("\r\n") != std::string::npos)
 703                         certinfo->dn.clear();
 704
 705                 X509_NAME_oneline(X509_get_issuer_name(cert), buf, sizeof(buf));
 706                 certinfo->issuer = buf;
 707                 if (certinfo->issuer.find_first_of("\r\n") != std::string::npos)
 708                         certinfo->issuer.clear();
 709
 710                 if (!X509_digest(cert, digest, md, &n))
 711                 {
 712                         certinfo->error = "Out of memory generating fingerprint";
 713                 }
 714                 else
 715                 {
 716                         certinfo->fingerprint = irc::hex(md, n);
 717                 }
 718
 719                 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))
 720                 {
 721                         certinfo->error = "Not activated, or expired certificate";
 722                 }
 723
 724                 X509_free(cert);
 725         }
 726 };
 727
 728 static int error_callback(const char *str, size_t len, void *u)
 729 {
 730         ServerInstance->Logs->Log("m_ssl_openssl",DEFAULT, "SSL error: " + std::string(str, len - 1));
 731
 732         //
 733         // XXX: Remove this line, it causes valgrind warnings...
 734         //
 735         // MD_update(&m, buf, j);
 736         //
 737         //
 738         // ... ONLY JOKING! :-)
 739         //
 740
 741         return 0;
 742 }
 743
 744 MODULE_INIT(ModuleSSLOpenSSL)