src/modules/extra/m_ssl_openssl.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2020 Matt Schatz <genius3000@g3k.solutions>
   5  *   Copyright (C) 2019 linuxdaemon <linuxdaemon.irc@gmail.com>
   6  *   Copyright (C) 2017 Wade Cline <wadecline@hotmail.com>
   7  *   Copyright (C) 2014, 2016 Adam <Adam@anope.org>
   8  *   Copyright (C) 2014 Julien Vehent <julien@linuxwall.info>
   9  *   Copyright (C) 2013-2014, 2016-2021 Sadie Powell <sadie@witchery.services>
  10  *   Copyright (C) 2012-2017 Attila Molnar <attilamolnar@hush.com>
  11  *   Copyright (C) 2012 Robby <robby@chatbelgie.be>
  12  *   Copyright (C) 2012 ChrisTX <xpipe@hotmail.de>
  13  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
  14  *   Copyright (C) 2008 Robin Burchell <robin+git@viroteck.net>
  15  *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
  16  *   Copyright (C) 2006-2008, 2010 Craig Edwards <brain@inspircd.org>
  17  *   Copyright (C) 2006 Oliver Lupton <om@inspircd.org>
  18  *
  19  * This file is part of InspIRCd.  InspIRCd is free software: you can
  20  * redistribute it and/or modify it under the terms of the GNU General Public
  21  * License as published by the Free Software Foundation, version 2.
  22  *
  23  * This program is distributed in the hope that it will be useful, but WITHOUT
  24  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  25  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  26  * details.
  27  *
  28  * You should have received a copy of the GNU General Public License
  29  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  30  */
  31
  32 /// $CompilerFlags: find_compiler_flags("openssl" "")
  33 /// $LinkerFlags: find_linker_flags("openssl" "-lssl -lcrypto")
  34
  35 /// $PackageInfo: require_system("arch") openssl pkgconf
  36 /// $PackageInfo: require_system("centos") openssl-devel pkgconfig
  37 /// $PackageInfo: require_system("darwin") openssl pkg-config
  38 /// $PackageInfo: require_system("debian") libssl-dev openssl pkg-config
  39 /// $PackageInfo: require_system("ubuntu") libssl-dev openssl pkg-config
  40
  41
  42 #include "inspircd.h"
  43 #include "iohook.h"
  44 #include "modules/ssl.h"
  45
  46 #ifdef __GNUC__
  47 # pragma GCC diagnostic push
  48 #endif
  49
  50 // Ignore OpenSSL deprecation warnings on OS X Lion and newer.
  51 #if defined __APPLE__
  52 # pragma GCC diagnostic ignored "-Wdeprecated-declarations"
  53 #endif
  54
  55 // LibreSSL lies about the version of OpenSSL it is compatible with and is a general pain
  56 // to support. Support for it was removed in the master branch at the same time that
  57 // support for OpenSSL pre-1.1 was.
  58 #if defined __GNUC__ && defined LIBRESSL_VERSION_NUMBER
  59 # warning LibreSSL support will be discontinued in the future. Consider using the ssl_gnutls or ssl_mbedtls modules instead.
  60 #endif
  61
  62 // Fix warnings about the use of `long long` on C++03.
  63 #if defined __clang__
  64 # pragma clang diagnostic ignored "-Wc++11-long-long"
  65 #elif defined __GNUC__
  66 # pragma GCC diagnostic ignored "-Wlong-long"
  67 #endif
  68
  69 #include <openssl/ssl.h>
  70 #include <openssl/err.h>
  71 #include <openssl/dh.h>
  72
  73 #ifdef __GNUC__
  74 # pragma GCC diagnostic pop
  75 #endif
  76
  77 #ifdef _WIN32
  78 # pragma comment(lib, "ssleay32.lib")
  79 # pragma comment(lib, "libeay32.lib")
  80 #endif
  81
  82 // Compatibility layer to allow OpenSSL 1.0 to use the 1.1 API.
  83 #if ((defined LIBRESSL_VERSION_NUMBER) || (OPENSSL_VERSION_NUMBER < 0x10100000L))
  84
  85 // BIO is opaque in OpenSSL 1.1 but the access API does not exist in 1.0.
  86 # define BIO_get_data(BIO) BIO->ptr
  87 # define BIO_set_data(BIO, VALUE) BIO->ptr = VALUE;
  88 # define BIO_set_init(BIO, VALUE) BIO->init = VALUE;
  89
  90 // These functions have been renamed in OpenSSL 1.1.
  91 # define OpenSSL_version SSLeay_version
  92 # define X509_getm_notAfter X509_get_notAfter
  93 # define X509_getm_notBefore X509_get_notBefore
  94 # define OPENSSL_init_ssl(OPTIONS, SETTINGS) \
  95         SSL_library_init(); \
  96         SSL_load_error_strings();
  97
  98 // These macros have been renamed in OpenSSL 1.1.
  99 # define OPENSSL_VERSION SSLEAY_VERSION
 100
 101 #else
 102 # define INSPIRCD_OPENSSL_OPAQUE_BIO
 103 #endif
 104
 105 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_OPEN };
 106
 107 static bool SelfSigned = false;
 108 static int exdataindex;
 109
 110 char* get_error()
 111 {
 112         return ERR_error_string(ERR_get_error(), NULL);
 113 }
 114
 115 static int OnVerify(int preverify_ok, X509_STORE_CTX* ctx);
 116 static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc);
 117
 118 namespace OpenSSL
 119 {
 120         class Exception : public ModuleException
 121         {
 122          public:
 123                 Exception(const std::string& reason)
 124                         : ModuleException(reason) { }
 125         };
 126
 127         class DHParams
 128         {
 129                 DH* dh;
 130
 131          public:
 132                 DHParams(const std::string& filename)
 133                 {
 134                         BIO* dhpfile = BIO_new_file(filename.c_str(), "r");
 135                         if (dhpfile == NULL)
 136                                 throw Exception("Couldn't open DH file " + filename);
 137
 138                         dh = PEM_read_bio_DHparams(dhpfile, NULL, NULL, NULL);
 139                         BIO_free(dhpfile);
 140
 141                         if (!dh)
 142                                 throw Exception("Couldn't read DH params from file " + filename);
 143                 }
 144
 145                 ~DHParams()
 146                 {
 147                         DH_free(dh);
 148                 }
 149
 150                 DH* get()
 151                 {
 152                         return dh;
 153                 }
 154         };
 155
 156         class Context
 157         {
 158                 SSL_CTX* const ctx;
 159                 long ctx_options;
 160
 161          public:
 162                 Context(SSL_CTX* context)
 163                         : ctx(context)
 164                 {
 165                         // Sane default options for OpenSSL see https://www.openssl.org/docs/ssl/SSL_CTX_set_options.html
 166                         // and when choosing a cipher, use the server's preferences instead of the client preferences.
 167                         long opts = SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 | SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION | SSL_OP_CIPHER_SERVER_PREFERENCE | 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
 178                         long mode = SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER;
 179 #ifdef SSL_MODE_RELEASE_BUFFERS
 180                         mode |= SSL_MODE_RELEASE_BUFFERS;
 181 #endif
 182                         SSL_CTX_set_mode(ctx, mode);
 183                         SSL_CTX_set_verify(ctx, SSL_VERIFY_NONE, NULL);
 184                         SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF);
 185                         SSL_CTX_set_info_callback(ctx, StaticSSLInfoCallback);
 186                 }
 187
 188                 ~Context()
 189                 {
 190                         SSL_CTX_free(ctx);
 191                 }
 192
 193                 bool SetDH(DHParams& dh)
 194                 {
 195                         ERR_clear_error();
 196                         return (SSL_CTX_set_tmp_dh(ctx, dh.get()) >= 0);
 197                 }
 198
 199 #ifndef OPENSSL_NO_ECDH
 200                 void SetECDH(const std::string& curvename)
 201                 {
 202                         int nid = OBJ_sn2nid(curvename.c_str());
 203                         if (nid == 0)
 204                                 throw Exception("Unknown curve: " + curvename);
 205
 206                         EC_KEY* eckey = EC_KEY_new_by_curve_name(nid);
 207                         if (!eckey)
 208                                 throw Exception("Unable to create EC key object");
 209
 210                         ERR_clear_error();
 211                         bool ret = (SSL_CTX_set_tmp_ecdh(ctx, eckey) >= 0);
 212                         EC_KEY_free(eckey);
 213                         if (!ret)
 214                                 throw Exception("Couldn't set ECDH parameters");
 215                 }
 216 #endif
 217
 218                 bool SetCiphers(const std::string& ciphers)
 219                 {
 220                         // TLSv1 to TLSv1.2 ciphers.
 221                         ERR_clear_error();
 222                         return SSL_CTX_set_cipher_list(ctx, ciphers.c_str());
 223                 }
 224
 225 #if OPENSSL_VERSION_NUMBER >= 0x10101000L
 226                 bool SetCiphersuites(const std::string& ciphers)
 227                 {
 228                         // TLSv1.3+ ciphers.
 229                         ERR_clear_error();
 230                         return SSL_CTX_set_ciphersuites(ctx, ciphers.c_str());
 231                 }
 232 #endif
 233
 234                 bool SetCerts(const std::string& filename)
 235                 {
 236                         ERR_clear_error();
 237                         return SSL_CTX_use_certificate_chain_file(ctx, filename.c_str());
 238                 }
 239
 240                 bool SetPrivateKey(const std::string& filename)
 241                 {
 242                         ERR_clear_error();
 243                         return SSL_CTX_use_PrivateKey_file(ctx, filename.c_str(), SSL_FILETYPE_PEM);
 244                 }
 245
 246                 bool SetCA(const std::string& filename)
 247                 {
 248                         ERR_clear_error();
 249                         return SSL_CTX_load_verify_locations(ctx, filename.c_str(), 0);
 250                 }
 251
 252                 void SetCRL(const std::string& crlfile, const std::string& crlpath, const std::string& crlmode)
 253                 {
 254                         if (crlfile.empty() && crlpath.empty())
 255                                 return;
 256
 257                         /* Set CRL mode */
 258                         unsigned long crlflags = X509_V_FLAG_CRL_CHECK;
 259                         if (stdalgo::string::equalsci(crlmode, "chain"))
 260                         {
 261                                 crlflags |= X509_V_FLAG_CRL_CHECK_ALL;
 262                         }
 263                         else if (!stdalgo::string::equalsci(crlmode, "leaf"))
 264                         {
 265                                 throw ModuleException("Unknown mode '" + crlmode + "'; expected either 'chain' (default) or 'leaf'");
 266                         }
 267
 268                         /* Load CRL files */
 269                         X509_STORE* store = SSL_CTX_get_cert_store(ctx);
 270                         if (!store)
 271                         {
 272                                 throw ModuleException("Unable to get X509_STORE from TLS (SSL) context; this should never happen");
 273                         }
 274                         ERR_clear_error();
 275                         if (!X509_STORE_load_locations(store,
 276                                 crlfile.empty() ? NULL : crlfile.c_str(),
 277                                 crlpath.empty() ? NULL : crlpath.c_str()))
 278                         {
 279                                 int err = ERR_get_error();
 280                                 throw ModuleException("Unable to load CRL file '" + crlfile + "' or CRL path '" + crlpath + "': '" + (err ? ERR_error_string(err, NULL) : "unknown") + "'");
 281                         }
 282
 283                         /* Set CRL mode */
 284                         if (X509_STORE_set_flags(store, crlflags) != 1)
 285                         {
 286                                 throw ModuleException("Unable to set X509 CRL flags");
 287                         }
 288                 }
 289
 290
 291                 long GetDefaultContextOptions() const
 292                 {
 293                         return ctx_options;
 294                 }
 295
 296                 long SetRawContextOptions(long setoptions, long clearoptions)
 297                 {
 298                         // Clear everything
 299                         SSL_CTX_clear_options(ctx, SSL_CTX_get_options(ctx));
 300
 301                         // Set the default options and what is in the conf
 302                         SSL_CTX_set_options(ctx, ctx_options | setoptions);
 303                         return SSL_CTX_clear_options(ctx, clearoptions);
 304                 }
 305
 306                 void SetVerifyCert()
 307                 {
 308                         SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 309                 }
 310
 311                 SSL* CreateServerSession()
 312                 {
 313                         SSL* sess = SSL_new(ctx);
 314                         SSL_set_accept_state(sess); // Act as server
 315                         return sess;
 316                 }
 317
 318                 SSL* CreateClientSession()
 319                 {
 320                         SSL* sess = SSL_new(ctx);
 321                         SSL_set_connect_state(sess); // Act as client
 322                         return sess;
 323                 }
 324         };
 325
 326         class Profile
 327         {
 328                 /** Name of this profile
 329                  */
 330                 const std::string name;
 331
 332                 /** DH parameters in use
 333                  */
 334                 DHParams dh;
 335
 336                 /** OpenSSL makes us have two contexts, one for servers and one for clients
 337                  */
 338                 Context ctx;
 339                 Context clictx;
 340
 341                 /** Digest to use when generating fingerprints
 342                  */
 343                 const EVP_MD* digest;
 344
 345                 /** Last error, set by error_callback()
 346                  */
 347                 std::string lasterr;
 348
 349                 /** True if renegotiations are allowed, false if not
 350                  */
 351                 const bool allowrenego;
 352
 353                 /** Rough max size of records to send
 354                  */
 355                 const unsigned int outrecsize;
 356
 357                 static int error_callback(const char* str, size_t len, void* u)
 358                 {
 359                         Profile* profile = reinterpret_cast<Profile*>(u);
 360                         profile->lasterr = std::string(str, len - 1);
 361                         return 0;
 362                 }
 363
 364                 /** Set raw OpenSSL context (SSL_CTX) options from a config tag
 365                  * @param ctxname Name of the context, client or server
 366                  * @param tag Config tag defining this profile
 367                  * @param context Context object to manipulate
 368                  */
 369                 void SetContextOptions(const std::string& ctxname, ConfigTag* tag, Context& context)
 370                 {
 371                         long setoptions = tag->getInt(ctxname + "setoptions", 0);
 372                         long clearoptions = tag->getInt(ctxname + "clearoptions", 0);
 373
 374 #ifdef SSL_OP_NO_COMPRESSION
 375                         // Disable compression by default
 376                         if (!tag->getBool("compression", false))
 377                                 setoptions |= SSL_OP_NO_COMPRESSION;
 378 #endif
 379
 380                         // Disable TLSv1.0 by default.
 381                         if (!tag->getBool("tlsv1", false))
 382                                 setoptions |= SSL_OP_NO_TLSv1;
 383
 384 #ifdef SSL_OP_NO_TLSv1_1
 385                         // Enable TLSv1.1 by default.
 386                         if (!tag->getBool("tlsv11", true))
 387                                 setoptions |= SSL_OP_NO_TLSv1_1;
 388 #endif
 389
 390 #ifdef SSL_OP_NO_TLSv1_2
 391                         // Enable TLSv1.2 by default.
 392                         if (!tag->getBool("tlsv12", true))
 393                                 setoptions |= SSL_OP_NO_TLSv1_2;
 394 #endif
 395
 396                         if (!setoptions && !clearoptions)
 397                                 return; // Nothing to do
 398
 399                         ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Setting %s %s context options, default: %ld set: %ld clear: %ld", name.c_str(), ctxname.c_str(), ctx.GetDefaultContextOptions(), setoptions, clearoptions);
 400                         long final = context.SetRawContextOptions(setoptions, clearoptions);
 401                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "%s %s context options: %ld", name.c_str(), ctxname.c_str(), final);
 402                 }
 403
 404          public:
 405                 Profile(const std::string& profilename, ConfigTag* tag)
 406                         : name(profilename)
 407                         , dh(ServerInstance->Config->Paths.PrependConfig(tag->getString("dhfile", "dhparams.pem", 1)))
 408                         , ctx(SSL_CTX_new(SSLv23_server_method()))
 409                         , clictx(SSL_CTX_new(SSLv23_client_method()))
 410                         , allowrenego(tag->getBool("renegotiation")) // Disallow by default
 411                         , outrecsize(tag->getUInt("outrecsize", 2048, 512, 16384))
 412                 {
 413                         if ((!ctx.SetDH(dh)) || (!clictx.SetDH(dh)))
 414                                 throw Exception("Couldn't set DH parameters");
 415
 416                         const std::string hash = tag->getString("hash", "md5", 1);
 417                         digest = EVP_get_digestbyname(hash.c_str());
 418                         if (digest == NULL)
 419                                 throw Exception("Unknown hash type " + hash);
 420
 421                         const std::string ciphers = tag->getString("ciphers");
 422                         if (!ciphers.empty())
 423                         {
 424                                 if ((!ctx.SetCiphers(ciphers)) || (!clictx.SetCiphers(ciphers)))
 425                                 {
 426                                         ERR_print_errors_cb(error_callback, this);
 427                                         throw Exception("Can't set cipher list to \"" + ciphers + "\" " + lasterr);
 428                                 }
 429                         }
 430
 431                         const std::string ciphersuites = tag->getString("ciphersuites");
 432                         if (!ciphers.empty())
 433                         {
 434 #if OPENSSL_VERSION_NUMBER >= 0x10101000L
 435                                 if ((!ctx.SetCiphersuites(ciphersuites)) || (!clictx.SetCiphersuites(ciphersuites)))
 436                                 {
 437                                         ERR_print_errors_cb(error_callback, this);
 438                                         throw Exception("Can't set ciphersuite list to \"" + ciphersuites + "\" " + lasterr);
 439                                 }
 440 #else
 441                                 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "You have configured <sslprofile:ciphersuites> but your version of OpenSSL does not support TLSv1.3+");
 442 #endif
 443                         }
 444
 445 #ifndef OPENSSL_NO_ECDH
 446                         const std::string curvename = tag->getString("ecdhcurve", "prime256v1", 1);
 447                         if (!curvename.empty())
 448                                 ctx.SetECDH(curvename);
 449 #endif
 450
 451                         SetContextOptions("server", tag, ctx);
 452                         SetContextOptions("client", tag, clictx);
 453
 454                         /* Load our keys and certificates
 455                          * NOTE: OpenSSL's error logging API sucks, don't blame us for this clusterfuck.
 456                          */
 457                         std::string filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("certfile", "cert.pem", 1));
 458                         if ((!ctx.SetCerts(filename)) || (!clictx.SetCerts(filename)))
 459                         {
 460                                 ERR_print_errors_cb(error_callback, this);
 461                                 throw Exception("Can't read certificate file: " + lasterr);
 462                         }
 463
 464                         filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("keyfile", "key.pem", 1));
 465                         if ((!ctx.SetPrivateKey(filename)) || (!clictx.SetPrivateKey(filename)))
 466                         {
 467                                 ERR_print_errors_cb(error_callback, this);
 468                                 throw Exception("Can't read key file: " + lasterr);
 469                         }
 470
 471                         // Load the CAs we trust
 472                         filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("cafile", "ca.pem", 1));
 473                         if ((!ctx.SetCA(filename)) || (!clictx.SetCA(filename)))
 474                         {
 475                                 ERR_print_errors_cb(error_callback, this);
 476                                 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());
 477                         }
 478
 479                         // Load the CRLs.
 480                         const std::string crlfile = tag->getString("crlfile");
 481                         const std::string crlpath = tag->getString("crlpath");
 482                         const std::string crlmode = tag->getString("crlmode", "chain", 1);
 483                         ctx.SetCRL(crlfile, crlpath, crlmode);
 484
 485                         clictx.SetVerifyCert();
 486                         if (tag->getBool("requestclientcert", true))
 487                                 ctx.SetVerifyCert();
 488                 }
 489
 490                 const std::string& GetName() const { return name; }
 491                 SSL* CreateServerSession() { return ctx.CreateServerSession(); }
 492                 SSL* CreateClientSession() { return clictx.CreateClientSession(); }
 493                 const EVP_MD* GetDigest() { return digest; }
 494                 bool AllowRenegotiation() const { return allowrenego; }
 495                 unsigned int GetOutgoingRecordSize() const { return outrecsize; }
 496         };
 497
 498         namespace BIOMethod
 499         {
 500                 static int create(BIO* bio)
 501                 {
 502                         BIO_set_init(bio, 1);
 503                         return 1;
 504                 }
 505
 506                 static int destroy(BIO* bio)
 507                 {
 508                         // XXX: Dummy function to avoid a memory leak in OpenSSL.
 509                         // The memory leak happens in BIO_free() (bio_lib.c) when the destroy func of the BIO is NULL.
 510                         // This is fixed in OpenSSL but some distros still ship the unpatched version hence we provide this workaround.
 511                         return 1;
 512                 }
 513
 514                 static long ctrl(BIO* bio, int cmd, long num, void* ptr)
 515                 {
 516                         if (cmd == BIO_CTRL_FLUSH)
 517                                 return 1;
 518                         return 0;
 519                 }
 520
 521                 static int read(BIO* bio, char* buf, int len);
 522                 static int write(BIO* bio, const char* buf, int len);
 523
 524 #ifdef INSPIRCD_OPENSSL_OPAQUE_BIO
 525                 static BIO_METHOD* alloc()
 526                 {
 527                         BIO_METHOD* meth = BIO_meth_new(100 | BIO_TYPE_SOURCE_SINK, "inspircd");
 528                         BIO_meth_set_write(meth, OpenSSL::BIOMethod::write);
 529                         BIO_meth_set_read(meth, OpenSSL::BIOMethod::read);
 530                         BIO_meth_set_ctrl(meth, OpenSSL::BIOMethod::ctrl);
 531                         BIO_meth_set_create(meth, OpenSSL::BIOMethod::create);
 532                         BIO_meth_set_destroy(meth, OpenSSL::BIOMethod::destroy);
 533                         return meth;
 534                 }
 535 #endif
 536         }
 537 }
 538
 539 // BIO_METHOD is opaque in OpenSSL 1.1 so we can't do this.
 540 // See OpenSSL::BIOMethod::alloc for the new method.
 541 #ifndef INSPIRCD_OPENSSL_OPAQUE_BIO
 542 static BIO_METHOD biomethods =
 543 {
 544         (100 | BIO_TYPE_SOURCE_SINK),
 545         "inspircd",
 546         OpenSSL::BIOMethod::write,
 547         OpenSSL::BIOMethod::read,
 548         NULL, // puts
 549         NULL, // gets
 550         OpenSSL::BIOMethod::ctrl,
 551         OpenSSL::BIOMethod::create,
 552         OpenSSL::BIOMethod::destroy, // destroy, does nothing, see function body for more info
 553         NULL // callback_ctrl
 554 };
 555 #else
 556 static BIO_METHOD* biomethods;
 557 #endif
 558
 559 static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx)
 560 {
 561         /* XXX: This will allow self signed certificates.
 562          * In the future if we want an option to not allow this,
 563          * we can just return preverify_ok here, and openssl
 564          * will boot off self-signed and invalid peer certs.
 565          */
 566         int ve = X509_STORE_CTX_get_error(ctx);
 567
 568         SelfSigned = (ve == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
 569
 570         return 1;
 571 }
 572
 573 class OpenSSLIOHook : public SSLIOHook
 574 {
 575  private:
 576         SSL* sess;
 577         issl_status status;
 578         bool data_to_write;
 579
 580         // Returns 1 if handshake succeeded, 0 if it is still in progress, -1 if it failed
 581         int Handshake(StreamSocket* user)
 582         {
 583                 ERR_clear_error();
 584                 int ret = SSL_do_handshake(sess);
 585                 if (ret < 0)
 586                 {
 587                         int err = SSL_get_error(sess, ret);
 588
 589                         if (err == SSL_ERROR_WANT_READ)
 590                         {
 591                                 SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 592                                 this->status = ISSL_HANDSHAKING;
 593                                 return 0;
 594                         }
 595                         else if (err == SSL_ERROR_WANT_WRITE)
 596                         {
 597                                 SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 598                                 this->status = ISSL_HANDSHAKING;
 599                                 return 0;
 600                         }
 601                         else
 602                         {
 603                                 CloseSession();
 604                                 return -1;
 605                         }
 606                 }
 607                 else if (ret > 0)
 608                 {
 609                         // Handshake complete.
 610                         VerifyCertificate();
 611
 612                         status = ISSL_OPEN;
 613
 614                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 615
 616                         return 1;
 617                 }
 618                 else if (ret == 0)
 619                 {
 620                         CloseSession();
 621                 }
 622                 return -1;
 623         }
 624
 625         void CloseSession()
 626         {
 627                 if (sess)
 628                 {
 629                         SSL_shutdown(sess);
 630                         SSL_free(sess);
 631                 }
 632                 sess = NULL;
 633                 certificate = NULL;
 634                 status = ISSL_NONE;
 635         }
 636
 637         void VerifyCertificate()
 638         {
 639                 X509* cert;
 640                 ssl_cert* certinfo = new ssl_cert;
 641                 this->certificate = certinfo;
 642                 unsigned int n;
 643                 unsigned char md[EVP_MAX_MD_SIZE];
 644
 645                 cert = SSL_get_peer_certificate(sess);
 646
 647                 if (!cert)
 648                 {
 649                         certinfo->error = "Could not get peer certificate: "+std::string(get_error());
 650                         return;
 651                 }
 652
 653                 certinfo->invalid = (SSL_get_verify_result(sess) != X509_V_OK);
 654
 655                 if (!SelfSigned)
 656                 {
 657                         certinfo->unknownsigner = false;
 658                         certinfo->trusted = true;
 659                 }
 660                 else
 661                 {
 662                         certinfo->unknownsigner = true;
 663                         certinfo->trusted = false;
 664                 }
 665
 666                 char buf[512];
 667                 X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
 668                 certinfo->dn = buf;
 669                 // Make sure there are no chars in the string that we consider invalid
 670                 if (certinfo->dn.find_first_of("\r\n") != std::string::npos)
 671                         certinfo->dn.clear();
 672
 673                 X509_NAME_oneline(X509_get_issuer_name(cert), buf, sizeof(buf));
 674                 certinfo->issuer = buf;
 675                 if (certinfo->issuer.find_first_of("\r\n") != std::string::npos)
 676                         certinfo->issuer.clear();
 677
 678                 if (!X509_digest(cert, GetProfile().GetDigest(), md, &n))
 679                 {
 680                         certinfo->error = "Out of memory generating fingerprint";
 681                 }
 682                 else
 683                 {
 684                         certinfo->fingerprint = BinToHex(md, n);
 685                 }
 686
 687                 if ((ASN1_UTCTIME_cmp_time_t(X509_getm_notAfter(cert), ServerInstance->Time()) == -1) || (ASN1_UTCTIME_cmp_time_t(X509_getm_notBefore(cert), ServerInstance->Time()) == 0))
 688                 {
 689                         certinfo->error = "Not activated, or expired certificate";
 690                 }
 691
 692                 X509_free(cert);
 693         }
 694
 695         void SSLInfoCallback(int where, int rc)
 696         {
 697                 if ((where & SSL_CB_HANDSHAKE_START) && (status == ISSL_OPEN))
 698                 {
 699                         if (GetProfile().AllowRenegotiation())
 700                                 return;
 701
 702                         // The other side is trying to renegotiate, kill the connection and change status
 703                         // to ISSL_NONE so CheckRenego() closes the session
 704                         status = ISSL_NONE;
 705                         BIO* bio = SSL_get_rbio(sess);
 706                         EventHandler* eh = static_cast<StreamSocket*>(BIO_get_data(bio));
 707                         SocketEngine::Shutdown(eh, 2);
 708                 }
 709         }
 710
 711         bool CheckRenego(StreamSocket* sock)
 712         {
 713                 if (status != ISSL_NONE)
 714                         return true;
 715
 716                 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Session %p killed, attempted to renegotiate", (void*)sess);
 717                 CloseSession();
 718                 sock->SetError("Renegotiation is not allowed");
 719                 return false;
 720         }
 721
 722         // Returns 1 if application I/O should proceed, 0 if it must wait for the underlying protocol to progress, -1 on fatal error
 723         int PrepareIO(StreamSocket* sock)
 724         {
 725                 if (status == ISSL_OPEN)
 726                         return 1;
 727                 else if (status == ISSL_HANDSHAKING)
 728                 {
 729                         // The handshake isn't finished, try to finish it
 730                         return Handshake(sock);
 731                 }
 732
 733                 CloseSession();
 734                 return -1;
 735         }
 736
 737         // Calls our private SSLInfoCallback()
 738         friend void StaticSSLInfoCallback(const SSL* ssl, int where, int rc);
 739
 740  public:
 741         OpenSSLIOHook(IOHookProvider* hookprov, StreamSocket* sock, SSL* session)
 742                 : SSLIOHook(hookprov)
 743                 , sess(session)
 744                 , status(ISSL_NONE)
 745                 , data_to_write(false)
 746         {
 747                 // Create BIO instance and store a pointer to the socket in it which will be used by the read and write functions
 748 #ifdef INSPIRCD_OPENSSL_OPAQUE_BIO
 749                 BIO* bio = BIO_new(biomethods);
 750 #else
 751                 BIO* bio = BIO_new(&biomethods);
 752 #endif
 753                 BIO_set_data(bio, sock);
 754                 SSL_set_bio(sess, bio, bio);
 755
 756                 SSL_set_ex_data(sess, exdataindex, this);
 757                 sock->AddIOHook(this);
 758                 Handshake(sock);
 759         }
 760
 761         void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE
 762         {
 763                 CloseSession();
 764         }
 765
 766         int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE
 767         {
 768                 // Finish handshake if needed
 769                 int prepret = PrepareIO(user);
 770                 if (prepret <= 0)
 771                         return prepret;
 772
 773                 // If we resumed the handshake then this->status will be ISSL_OPEN
 774                 {
 775                         ERR_clear_error();
 776                         char* buffer = ServerInstance->GetReadBuffer();
 777                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 778                         int ret = SSL_read(sess, buffer, bufsiz);
 779
 780                         if (!CheckRenego(user))
 781                                 return -1;
 782
 783                         if (ret > 0)
 784                         {
 785                                 recvq.append(buffer, ret);
 786                                 int mask = 0;
 787                                 // Schedule a read if there is still data in the OpenSSL buffer
 788                                 if (SSL_pending(sess) > 0)
 789                                         mask |= FD_ADD_TRIAL_READ;
 790                                 if (data_to_write)
 791                                         mask |= FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE;
 792                                 if (mask != 0)
 793                                         SocketEngine::ChangeEventMask(user, mask);
 794                                 return 1;
 795                         }
 796                         else if (ret == 0)
 797                         {
 798                                 // Client closed connection.
 799                                 CloseSession();
 800                                 user->SetError("Connection closed");
 801                                 return -1;
 802                         }
 803                         else // if (ret < 0)
 804                         {
 805                                 int err = SSL_get_error(sess, ret);
 806
 807                                 if (err == SSL_ERROR_WANT_READ)
 808                                 {
 809                                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ);
 810                                         return 0;
 811                                 }
 812                                 else if (err == SSL_ERROR_WANT_WRITE)
 813                                 {
 814                                         SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 815                                         return 0;
 816                                 }
 817                                 else
 818                                 {
 819                                         CloseSession();
 820                                         return -1;
 821                                 }
 822                         }
 823                 }
 824         }
 825
 826         int OnStreamSocketWrite(StreamSocket* user, StreamSocket::SendQueue& sendq) CXX11_OVERRIDE
 827         {
 828                 // Finish handshake if needed
 829                 int prepret = PrepareIO(user);
 830                 if (prepret <= 0)
 831                         return prepret;
 832
 833                 data_to_write = true;
 834
 835                 // Session is ready for transferring application data
 836                 while (!sendq.empty())
 837                 {
 838                         ERR_clear_error();
 839                         FlattenSendQueue(sendq, GetProfile().GetOutgoingRecordSize());
 840                         const StreamSocket::SendQueue::Element& buffer = sendq.front();
 841                         int ret = SSL_write(sess, buffer.data(), buffer.size());
 842
 843                         if (!CheckRenego(user))
 844                                 return -1;
 845
 846                         if (ret == (int)buffer.length())
 847                         {
 848                                 // Wrote entire record, continue sending
 849                                 sendq.pop_front();
 850                         }
 851                         else if (ret > 0)
 852                         {
 853                                 sendq.erase_front(ret);
 854                                 SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 855                                 return 0;
 856                         }
 857                         else if (ret == 0)
 858                         {
 859                                 CloseSession();
 860                                 return -1;
 861                         }
 862                         else // if (ret < 0)
 863                         {
 864                                 int err = SSL_get_error(sess, ret);
 865
 866                                 if (err == SSL_ERROR_WANT_WRITE)
 867                                 {
 868                                         SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 869                                         return 0;
 870                                 }
 871                                 else if (err == SSL_ERROR_WANT_READ)
 872                                 {
 873                                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ);
 874                                         return 0;
 875                                 }
 876                                 else
 877                                 {
 878                                         CloseSession();
 879                                         return -1;
 880                                 }
 881                         }
 882                 }
 883
 884                 data_to_write = false;
 885                 SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 886                 return 1;
 887         }
 888
 889         void GetCiphersuite(std::string& out) const CXX11_OVERRIDE
 890         {
 891                 if (!IsHandshakeDone())
 892                         return;
 893                 out.append(SSL_get_version(sess)).push_back('-');
 894                 out.append(SSL_get_cipher(sess));
 895         }
 896
 897         bool GetServerName(std::string& out) const CXX11_OVERRIDE
 898         {
 899                 const char* name = SSL_get_servername(sess, TLSEXT_NAMETYPE_host_name);
 900                 if (!name)
 901                         return false;
 902
 903                 out.append(name);
 904                 return true;
 905         }
 906
 907         bool IsHandshakeDone() const { return (status == ISSL_OPEN); }
 908         OpenSSL::Profile& GetProfile();
 909 };
 910
 911 static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc)
 912 {
 913         OpenSSLIOHook* hook = static_cast<OpenSSLIOHook*>(SSL_get_ex_data(ssl, exdataindex));
 914         hook->SSLInfoCallback(where, rc);
 915 }
 916
 917 static int OpenSSL::BIOMethod::write(BIO* bio, const char* buffer, int size)
 918 {
 919         BIO_clear_retry_flags(bio);
 920
 921         StreamSocket* sock = static_cast<StreamSocket*>(BIO_get_data(bio));
 922         if (sock->GetEventMask() & FD_WRITE_WILL_BLOCK)
 923         {
 924                 // Writes blocked earlier, don't retry syscall
 925                 BIO_set_retry_write(bio);
 926                 return -1;
 927         }
 928
 929         int ret = SocketEngine::Send(sock, buffer, size, 0);
 930         if ((ret < size) && ((ret > 0) || (SocketEngine::IgnoreError())))
 931         {
 932                 // Blocked, set retry flag for OpenSSL
 933                 SocketEngine::ChangeEventMask(sock, FD_WRITE_WILL_BLOCK);
 934                 BIO_set_retry_write(bio);
 935         }
 936
 937         return ret;
 938 }
 939
 940 static int OpenSSL::BIOMethod::read(BIO* bio, char* buffer, int size)
 941 {
 942         BIO_clear_retry_flags(bio);
 943
 944         StreamSocket* sock = static_cast<StreamSocket*>(BIO_get_data(bio));
 945         if (sock->GetEventMask() & FD_READ_WILL_BLOCK)
 946         {
 947                 // Reads blocked earlier, don't retry syscall
 948                 BIO_set_retry_read(bio);
 949                 return -1;
 950         }
 951
 952         int ret = SocketEngine::Recv(sock, buffer, size, 0);
 953         if ((ret < size) && ((ret > 0) || (SocketEngine::IgnoreError())))
 954         {
 955                 // Blocked, set retry flag for OpenSSL
 956                 SocketEngine::ChangeEventMask(sock, FD_READ_WILL_BLOCK);
 957                 BIO_set_retry_read(bio);
 958         }
 959
 960         return ret;
 961 }
 962
 963 class OpenSSLIOHookProvider : public SSLIOHookProvider
 964 {
 965         OpenSSL::Profile profile;
 966
 967  public:
 968         OpenSSLIOHookProvider(Module* mod, const std::string& profilename, ConfigTag* tag)
 969                 : SSLIOHookProvider(mod, profilename)
 970                 , profile(profilename, tag)
 971         {
 972                 ServerInstance->Modules->AddService(*this);
 973         }
 974
 975         ~OpenSSLIOHookProvider()
 976         {
 977                 ServerInstance->Modules->DelService(*this);
 978         }
 979
 980         void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE
 981         {
 982                 new OpenSSLIOHook(this, sock, profile.CreateServerSession());
 983         }
 984
 985         void OnConnect(StreamSocket* sock) CXX11_OVERRIDE
 986         {
 987                 new OpenSSLIOHook(this, sock, profile.CreateClientSession());
 988         }
 989
 990         OpenSSL::Profile& GetProfile() { return profile; }
 991 };
 992
 993 OpenSSL::Profile& OpenSSLIOHook::GetProfile()
 994 {
 995         IOHookProvider* hookprov = prov;
 996         return static_cast<OpenSSLIOHookProvider*>(hookprov)->GetProfile();
 997 }
 998
 999 class ModuleSSLOpenSSL : public Module
1000 {
1001         typedef std::vector<reference<OpenSSLIOHookProvider> > ProfileList;
1002
1003         ProfileList profiles;
1004
1005         void ReadProfiles()
1006         {
1007                 ProfileList newprofiles;
1008                 ConfigTagList tags = ServerInstance->Config->ConfTags("sslprofile");
1009                 if (tags.first == tags.second)
1010                 {
1011                         // Create a default profile named "openssl"
1012                         const std::string defname = "openssl";
1013                         ConfigTag* tag = ServerInstance->Config->ConfValue(defname);
1014                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "No <sslprofile> tags found, using settings from the deprecated <openssl> tag");
1015
1016                         try
1017                         {
1018                                 newprofiles.push_back(new OpenSSLIOHookProvider(this, defname, tag));
1019                         }
1020                         catch (OpenSSL::Exception& ex)
1021                         {
1022                                 throw ModuleException("Error while initializing the default TLS (SSL) profile - " + ex.GetReason());
1023                         }
1024                 }
1025                 else
1026                 {
1027                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "You have defined an <sslprofile> tag; you should use this in place of \"openssl\" when configuring TLS (SSL) connections in <bind:sslprofile> or <link:sslprofile>");
1028                         for (ConfigIter i = tags.first; i != tags.second; ++i)
1029                         {
1030                                 ConfigTag* tag = i->second;
1031                                 if (!stdalgo::string::equalsci(tag->getString("provider"), "openssl"))
1032                                 {
1033                                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Ignoring non-OpenSSL <sslprofile> tag at " + tag->getTagLocation());
1034                                         continue;
1035                                 }
1036
1037                                 std::string name = tag->getString("name");
1038                                 if (name.empty())
1039                                 {
1040                                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Ignoring <sslprofile> tag without name at " + tag->getTagLocation());
1041                                         continue;
1042                                 }
1043
1044                                 reference<OpenSSLIOHookProvider> prov;
1045                                 try
1046                                 {
1047                                         prov = new OpenSSLIOHookProvider(this, name, tag);
1048                                 }
1049                                 catch (CoreException& ex)
1050                                 {
1051                                         throw ModuleException("Error while initializing TLS (SSL) profile \"" + name + "\" at " + tag->getTagLocation() + " - " + ex.GetReason());
1052                                 }
1053
1054                                 newprofiles.push_back(prov);
1055                         }
1056                 }
1057
1058                 for (ProfileList::iterator i = profiles.begin(); i != profiles.end(); ++i)
1059                 {
1060                         OpenSSLIOHookProvider& prov = **i;
1061                         ServerInstance->Modules.DelService(prov);
1062                 }
1063
1064                 profiles.swap(newprofiles);
1065         }
1066
1067  public:
1068         ModuleSSLOpenSSL()
1069         {
1070                 // Initialize OpenSSL
1071                 OPENSSL_init_ssl(0, NULL);
1072 #ifdef INSPIRCD_OPENSSL_OPAQUE_BIO
1073                 biomethods = OpenSSL::BIOMethod::alloc();
1074         }
1075
1076         ~ModuleSSLOpenSSL()
1077         {
1078                 BIO_meth_free(biomethods);
1079 #endif
1080         }
1081
1082         void init() CXX11_OVERRIDE
1083         {
1084                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "OpenSSL lib version \"%s\" module was compiled for \"" OPENSSL_VERSION_TEXT "\"", OpenSSL_version(OPENSSL_VERSION));
1085
1086                 // Register application specific data
1087                 char exdatastr[] = "inspircd";
1088                 exdataindex = SSL_get_ex_new_index(0, exdatastr, NULL, NULL, NULL);
1089                 if (exdataindex < 0)
1090                         throw ModuleException("Failed to register application specific data");
1091
1092                 ReadProfiles();
1093         }
1094
1095         void OnModuleRehash(User* user, const std::string &param) CXX11_OVERRIDE
1096         {
1097                 if (!irc::equals(param, "tls") && !irc::equals(param, "ssl"))
1098                         return;
1099
1100                 try
1101                 {
1102                         ReadProfiles();
1103                         ServerInstance->SNO->WriteToSnoMask('a', "OpenSSL TLS (SSL) profiles have been reloaded.");
1104                 }
1105                 catch (ModuleException& ex)
1106                 {
1107                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, ex.GetReason() + " Not applying settings.");
1108                 }
1109         }
1110
1111         void OnCleanup(ExtensionItem::ExtensibleType type, Extensible* item) CXX11_OVERRIDE
1112         {
1113                 if (type == ExtensionItem::EXT_USER)
1114                 {
1115                         LocalUser* user = IS_LOCAL((User*)item);
1116
1117                         if ((user) && (user->eh.GetModHook(this)))
1118                         {
1119                                 // User is using TLS (SSL), they're a local user, and they're using one of *our* TLS (SSL) ports.
1120                                 // Potentially there could be multiple TLS (SSL) modules loaded at once on different ports.
1121                                 ServerInstance->Users->QuitUser(user, "OpenSSL module unloading");
1122                         }
1123                 }
1124         }
1125
1126         ModResult OnCheckReady(LocalUser* user) CXX11_OVERRIDE
1127         {
1128                 const OpenSSLIOHook* const iohook = static_cast<OpenSSLIOHook*>(user->eh.GetModHook(this));
1129                 if ((iohook) && (!iohook->IsHandshakeDone()))
1130                         return MOD_RES_DENY;
1131                 return MOD_RES_PASSTHRU;
1132         }
1133
1134         Version GetVersion() CXX11_OVERRIDE
1135         {
1136                 return Version("Allows TLS (SSL) encrypted connections using the OpenSSL library.", VF_VENDOR);
1137         }
1138 };
1139
1140 MODULE_INIT(ModuleSSLOpenSSL)