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 /// $CompilerFlags: find_compiler_flags("openssl")
  25 /// $LinkerFlags: find_linker_flags("openssl" "-lssl -lcrypto")
  26
  27 /// $PackageInfo: require_system("centos") openssl-devel pkgconfig
  28 /// $PackageInfo: require_system("darwin") openssl pkg-config
  29 /// $PackageInfo: require_system("debian") libssl-dev openssl pkg-config
  30 /// $PackageInfo: require_system("ubuntu") libssl-dev openssl pkg-config
  31
  32
  33 #include "inspircd.h"
  34 #include "iohook.h"
  35 #include "modules/ssl.h"
  36
  37 // Ignore OpenSSL deprecation warnings on OS X Lion and newer.
  38 #if defined __APPLE__
  39 # pragma GCC diagnostic ignored "-Wdeprecated-declarations"
  40 #endif
  41
  42 // Fix warnings about the use of `long long` on C++03.
  43 #if defined __clang__
  44 # pragma clang diagnostic ignored "-Wc++11-long-long"
  45 #elif defined __GNUC__
  46 # pragma GCC diagnostic ignored "-Wlong-long"
  47 #endif
  48
  49 #include <openssl/ssl.h>
  50 #include <openssl/err.h>
  51
  52 #ifdef _WIN32
  53 # pragma comment(lib, "ssleay32.lib")
  54 # pragma comment(lib, "libeay32.lib")
  55 #endif
  56
  57 #if ((OPENSSL_VERSION_NUMBER >= 0x10000000L) && (!(defined(OPENSSL_NO_ECDH))))
  58 // OpenSSL 0.9.8 includes some ECC support, but it's unfinished. Enable only for 1.0.0 and later.
  59 #define INSPIRCD_OPENSSL_ENABLE_ECDH
  60 #endif
  61
  62 // BIO is opaque in OpenSSL 1.1 but the access API does not exist in 1.0 and older.
  63 #if ((defined LIBRESSL_VERSION_NUMBER) || (OPENSSL_VERSION_NUMBER < 0x10100000L))
  64 # define BIO_get_data(BIO) BIO->ptr
  65 # define BIO_set_data(BIO, VALUE) BIO->ptr = VALUE;
  66 # define BIO_set_init(BIO, VALUE) BIO->init = VALUE;
  67 #else
  68 # define INSPIRCD_OPENSSL_OPAQUE_BIO
  69 #endif
  70
  71 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_OPEN };
  72
  73 static bool SelfSigned = false;
  74 static int exdataindex;
  75
  76 char* get_error()
  77 {
  78         return ERR_error_string(ERR_get_error(), NULL);
  79 }
  80
  81 static int OnVerify(int preverify_ok, X509_STORE_CTX* ctx);
  82 static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc);
  83
  84 namespace OpenSSL
  85 {
  86         class Exception : public ModuleException
  87         {
  88          public:
  89                 Exception(const std::string& reason)
  90                         : ModuleException(reason) { }
  91         };
  92
  93         class DHParams
  94         {
  95                 DH* dh;
  96
  97          public:
  98                 DHParams(const std::string& filename)
  99                 {
 100                         BIO* dhpfile = BIO_new_file(filename.c_str(), "r");
 101                         if (dhpfile == NULL)
 102                                 throw Exception("Couldn't open DH file " + filename);
 103
 104                         dh = PEM_read_bio_DHparams(dhpfile, NULL, NULL, NULL);
 105                         BIO_free(dhpfile);
 106
 107                         if (!dh)
 108                                 throw Exception("Couldn't read DH params from file " + filename);
 109                 }
 110
 111                 ~DHParams()
 112                 {
 113                         DH_free(dh);
 114                 }
 115
 116                 DH* get()
 117                 {
 118                         return dh;
 119                 }
 120         };
 121
 122         class Context
 123         {
 124                 SSL_CTX* const ctx;
 125                 long ctx_options;
 126
 127          public:
 128                 Context(SSL_CTX* context)
 129                         : ctx(context)
 130                 {
 131                         // Sane default options for OpenSSL see https://www.openssl.org/docs/ssl/SSL_CTX_set_options.html
 132                         // and when choosing a cipher, use the server's preferences instead of the client preferences.
 133                         long opts = SSL_OP_NO_SSLv2 | SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION | SSL_OP_CIPHER_SERVER_PREFERENCE | SSL_OP_SINGLE_DH_USE;
 134                         // Only turn options on if they exist
 135 #ifdef SSL_OP_SINGLE_ECDH_USE
 136                         opts |= SSL_OP_SINGLE_ECDH_USE;
 137 #endif
 138 #ifdef SSL_OP_NO_TICKET
 139                         opts |= SSL_OP_NO_TICKET;
 140 #endif
 141
 142                         ctx_options = SSL_CTX_set_options(ctx, opts);
 143
 144                         long mode = SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER;
 145 #ifdef SSL_MODE_RELEASE_BUFFERS
 146                         mode |= SSL_MODE_RELEASE_BUFFERS;
 147 #endif
 148                         SSL_CTX_set_mode(ctx, mode);
 149                         SSL_CTX_set_verify(ctx, SSL_VERIFY_NONE, NULL);
 150                         SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF);
 151                         SSL_CTX_set_info_callback(ctx, StaticSSLInfoCallback);
 152                 }
 153
 154                 ~Context()
 155                 {
 156                         SSL_CTX_free(ctx);
 157                 }
 158
 159                 bool SetDH(DHParams& dh)
 160                 {
 161                         ERR_clear_error();
 162                         return (SSL_CTX_set_tmp_dh(ctx, dh.get()) >= 0);
 163                 }
 164
 165 #ifdef INSPIRCD_OPENSSL_ENABLE_ECDH
 166                 void SetECDH(const std::string& curvename)
 167                 {
 168                         int nid = OBJ_sn2nid(curvename.c_str());
 169                         if (nid == 0)
 170                                 throw Exception("Unknown curve: " + curvename);
 171
 172                         EC_KEY* eckey = EC_KEY_new_by_curve_name(nid);
 173                         if (!eckey)
 174                                 throw Exception("Unable to create EC key object");
 175
 176                         ERR_clear_error();
 177                         bool ret = (SSL_CTX_set_tmp_ecdh(ctx, eckey) >= 0);
 178                         EC_KEY_free(eckey);
 179                         if (!ret)
 180                                 throw Exception("Couldn't set ECDH parameters");
 181                 }
 182 #endif
 183
 184                 bool SetCiphers(const std::string& ciphers)
 185                 {
 186                         ERR_clear_error();
 187                         return SSL_CTX_set_cipher_list(ctx, ciphers.c_str());
 188                 }
 189
 190                 bool SetCerts(const std::string& filename)
 191                 {
 192                         ERR_clear_error();
 193                         return SSL_CTX_use_certificate_chain_file(ctx, filename.c_str());
 194                 }
 195
 196                 bool SetPrivateKey(const std::string& filename)
 197                 {
 198                         ERR_clear_error();
 199                         return SSL_CTX_use_PrivateKey_file(ctx, filename.c_str(), SSL_FILETYPE_PEM);
 200                 }
 201
 202                 bool SetCA(const std::string& filename)
 203                 {
 204                         ERR_clear_error();
 205                         return SSL_CTX_load_verify_locations(ctx, filename.c_str(), 0);
 206                 }
 207
 208                 long GetDefaultContextOptions() const
 209                 {
 210                         return ctx_options;
 211                 }
 212
 213                 long SetRawContextOptions(long setoptions, long clearoptions)
 214                 {
 215                         // Clear everything
 216                         SSL_CTX_clear_options(ctx, SSL_CTX_get_options(ctx));
 217
 218                         // Set the default options and what is in the conf
 219                         SSL_CTX_set_options(ctx, ctx_options | setoptions);
 220                         return SSL_CTX_clear_options(ctx, clearoptions);
 221                 }
 222
 223                 void SetVerifyCert()
 224                 {
 225                         SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
 226                 }
 227
 228                 SSL* CreateServerSession()
 229                 {
 230                         SSL* sess = SSL_new(ctx);
 231                         SSL_set_accept_state(sess); // Act as server
 232                         return sess;
 233                 }
 234
 235                 SSL* CreateClientSession()
 236                 {
 237                         SSL* sess = SSL_new(ctx);
 238                         SSL_set_connect_state(sess); // Act as client
 239                         return sess;
 240                 }
 241         };
 242
 243         class Profile
 244         {
 245                 /** Name of this profile
 246                  */
 247                 const std::string name;
 248
 249                 /** DH parameters in use
 250                  */
 251                 DHParams dh;
 252
 253                 /** OpenSSL makes us have two contexts, one for servers and one for clients
 254                  */
 255                 Context ctx;
 256                 Context clictx;
 257
 258                 /** Digest to use when generating fingerprints
 259                  */
 260                 const EVP_MD* digest;
 261
 262                 /** Last error, set by error_callback()
 263                  */
 264                 std::string lasterr;
 265
 266                 /** True if renegotiations are allowed, false if not
 267                  */
 268                 const bool allowrenego;
 269
 270                 /** Rough max size of records to send
 271                  */
 272                 const unsigned int outrecsize;
 273
 274                 static int error_callback(const char* str, size_t len, void* u)
 275                 {
 276                         Profile* profile = reinterpret_cast<Profile*>(u);
 277                         profile->lasterr = std::string(str, len - 1);
 278                         return 0;
 279                 }
 280
 281                 /** Set raw OpenSSL context (SSL_CTX) options from a config tag
 282                  * @param ctxname Name of the context, client or server
 283                  * @param tag Config tag defining this profile
 284                  * @param context Context object to manipulate
 285                  */
 286                 void SetContextOptions(const std::string& ctxname, ConfigTag* tag, Context& context)
 287                 {
 288                         long setoptions = tag->getInt(ctxname + "setoptions");
 289                         long clearoptions = tag->getInt(ctxname + "clearoptions");
 290 #ifdef SSL_OP_NO_COMPRESSION
 291                         if (!tag->getBool("compression", false)) // Disable compression by default
 292                                 setoptions |= SSL_OP_NO_COMPRESSION;
 293 #endif
 294                         if (!tag->getBool("sslv3", false)) // Disable SSLv3 by default
 295                                 setoptions |= SSL_OP_NO_SSLv3;
 296                         if (!tag->getBool("tlsv1", true))
 297                                 setoptions |= SSL_OP_NO_TLSv1;
 298
 299                         if (!setoptions && !clearoptions)
 300                                 return; // Nothing to do
 301
 302                         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);
 303                         long final = context.SetRawContextOptions(setoptions, clearoptions);
 304                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "%s %s context options: %ld", name.c_str(), ctxname.c_str(), final);
 305                 }
 306
 307          public:
 308                 Profile(const std::string& profilename, ConfigTag* tag)
 309                         : name(profilename)
 310                         , dh(ServerInstance->Config->Paths.PrependConfig(tag->getString("dhfile", "dhparams.pem")))
 311                         , ctx(SSL_CTX_new(SSLv23_server_method()))
 312                         , clictx(SSL_CTX_new(SSLv23_client_method()))
 313                         , allowrenego(tag->getBool("renegotiation")) // Disallow by default
 314                         , outrecsize(tag->getInt("outrecsize", 2048, 512, 16384))
 315                 {
 316                         if ((!ctx.SetDH(dh)) || (!clictx.SetDH(dh)))
 317                                 throw Exception("Couldn't set DH parameters");
 318
 319                         std::string hash = tag->getString("hash", "md5");
 320                         digest = EVP_get_digestbyname(hash.c_str());
 321                         if (digest == NULL)
 322                                 throw Exception("Unknown hash type " + hash);
 323
 324                         std::string ciphers = tag->getString("ciphers");
 325                         if (!ciphers.empty())
 326                         {
 327                                 if ((!ctx.SetCiphers(ciphers)) || (!clictx.SetCiphers(ciphers)))
 328                                 {
 329                                         ERR_print_errors_cb(error_callback, this);
 330                                         throw Exception("Can't set cipher list to \"" + ciphers + "\" " + lasterr);
 331                                 }
 332                         }
 333
 334 #ifdef INSPIRCD_OPENSSL_ENABLE_ECDH
 335                         std::string curvename = tag->getString("ecdhcurve", "prime256v1");
 336                         if (!curvename.empty())
 337                                 ctx.SetECDH(curvename);
 338 #endif
 339
 340                         SetContextOptions("server", tag, ctx);
 341                         SetContextOptions("client", tag, clictx);
 342
 343                         /* Load our keys and certificates
 344                          * NOTE: OpenSSL's error logging API sucks, don't blame us for this clusterfuck.
 345                          */
 346                         std::string filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("certfile", "cert.pem"));
 347                         if ((!ctx.SetCerts(filename)) || (!clictx.SetCerts(filename)))
 348                         {
 349                                 ERR_print_errors_cb(error_callback, this);
 350                                 throw Exception("Can't read certificate file: " + lasterr);
 351                         }
 352
 353                         filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("keyfile", "key.pem"));
 354                         if ((!ctx.SetPrivateKey(filename)) || (!clictx.SetPrivateKey(filename)))
 355                         {
 356                                 ERR_print_errors_cb(error_callback, this);
 357                                 throw Exception("Can't read key file: " + lasterr);
 358                         }
 359
 360                         // Load the CAs we trust
 361                         filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("cafile", "ca.pem"));
 362                         if ((!ctx.SetCA(filename)) || (!clictx.SetCA(filename)))
 363                         {
 364                                 ERR_print_errors_cb(error_callback, this);
 365                                 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());
 366                         }
 367
 368                         clictx.SetVerifyCert();
 369                         if (tag->getBool("requestclientcert", true))
 370                                 ctx.SetVerifyCert();
 371                 }
 372
 373                 const std::string& GetName() const { return name; }
 374                 SSL* CreateServerSession() { return ctx.CreateServerSession(); }
 375                 SSL* CreateClientSession() { return clictx.CreateClientSession(); }
 376                 const EVP_MD* GetDigest() { return digest; }
 377                 bool AllowRenegotiation() const { return allowrenego; }
 378                 unsigned int GetOutgoingRecordSize() const { return outrecsize; }
 379         };
 380
 381         namespace BIOMethod
 382         {
 383                 static int create(BIO* bio)
 384                 {
 385                         BIO_set_init(bio, 1);
 386                         return 1;
 387                 }
 388
 389                 static int destroy(BIO* bio)
 390                 {
 391                         // XXX: Dummy function to avoid a memory leak in OpenSSL.
 392                         // The memory leak happens in BIO_free() (bio_lib.c) when the destroy func of the BIO is NULL.
 393                         // This is fixed in OpenSSL but some distros still ship the unpatched version hence we provide this workaround.
 394                         return 1;
 395                 }
 396
 397                 static long ctrl(BIO* bio, int cmd, long num, void* ptr)
 398                 {
 399                         if (cmd == BIO_CTRL_FLUSH)
 400                                 return 1;
 401                         return 0;
 402                 }
 403
 404                 static int read(BIO* bio, char* buf, int len);
 405                 static int write(BIO* bio, const char* buf, int len);
 406
 407 #ifdef INSPIRCD_OPENSSL_OPAQUE_BIO
 408                 static BIO_METHOD* alloc()
 409                 {
 410                         BIO_METHOD* meth = BIO_meth_new(100 | BIO_TYPE_SOURCE_SINK, "inspircd");
 411                         BIO_meth_set_write(meth, OpenSSL::BIOMethod::write);
 412                         BIO_meth_set_read(meth, OpenSSL::BIOMethod::read);
 413                         BIO_meth_set_ctrl(meth, OpenSSL::BIOMethod::ctrl);
 414                         BIO_meth_set_create(meth, OpenSSL::BIOMethod::create);
 415                         BIO_meth_set_destroy(meth, OpenSSL::BIOMethod::destroy);
 416                         return meth;
 417                 }
 418 #endif
 419         }
 420 }
 421
 422 // BIO_METHOD is opaque in OpenSSL 1.1 so we can't do this.
 423 // See OpenSSL::BIOMethod::alloc for the new method.
 424 #ifndef INSPIRCD_OPENSSL_OPAQUE_BIO
 425 static BIO_METHOD biomethods =
 426 {
 427         (100 | BIO_TYPE_SOURCE_SINK),
 428         "inspircd",
 429         OpenSSL::BIOMethod::write,
 430         OpenSSL::BIOMethod::read,
 431         NULL, // puts
 432         NULL, // gets
 433         OpenSSL::BIOMethod::ctrl,
 434         OpenSSL::BIOMethod::create,
 435         OpenSSL::BIOMethod::destroy, // destroy, does nothing, see function body for more info
 436         NULL // callback_ctrl
 437 };
 438 #else
 439 static BIO_METHOD* biomethods;
 440 #endif
 441
 442 static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx)
 443 {
 444         /* XXX: This will allow self signed certificates.
 445          * In the future if we want an option to not allow this,
 446          * we can just return preverify_ok here, and openssl
 447          * will boot off self-signed and invalid peer certs.
 448          */
 449         int ve = X509_STORE_CTX_get_error(ctx);
 450
 451         SelfSigned = (ve == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
 452
 453         return 1;
 454 }
 455
 456 class OpenSSLIOHook : public SSLIOHook
 457 {
 458  private:
 459         SSL* sess;
 460         issl_status status;
 461         bool data_to_write;
 462
 463         // Returns 1 if handshake succeeded, 0 if it is still in progress, -1 if it failed
 464         int Handshake(StreamSocket* user)
 465         {
 466                 ERR_clear_error();
 467                 int ret = SSL_do_handshake(sess);
 468                 if (ret < 0)
 469                 {
 470                         int err = SSL_get_error(sess, ret);
 471
 472                         if (err == SSL_ERROR_WANT_READ)
 473                         {
 474                                 SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 475                                 this->status = ISSL_HANDSHAKING;
 476                                 return 0;
 477                         }
 478                         else if (err == SSL_ERROR_WANT_WRITE)
 479                         {
 480                                 SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 481                                 this->status = ISSL_HANDSHAKING;
 482                                 return 0;
 483                         }
 484                         else
 485                         {
 486                                 CloseSession();
 487                                 return -1;
 488                         }
 489                 }
 490                 else if (ret > 0)
 491                 {
 492                         // Handshake complete.
 493                         VerifyCertificate();
 494
 495                         status = ISSL_OPEN;
 496
 497                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 498
 499                         return 1;
 500                 }
 501                 else if (ret == 0)
 502                 {
 503                         CloseSession();
 504                 }
 505                 return -1;
 506         }
 507
 508         void CloseSession()
 509         {
 510                 if (sess)
 511                 {
 512                         SSL_shutdown(sess);
 513                         SSL_free(sess);
 514                 }
 515                 sess = NULL;
 516                 certificate = NULL;
 517                 status = ISSL_NONE;
 518         }
 519
 520         void VerifyCertificate()
 521         {
 522                 X509* cert;
 523                 ssl_cert* certinfo = new ssl_cert;
 524                 this->certificate = certinfo;
 525                 unsigned int n;
 526                 unsigned char md[EVP_MAX_MD_SIZE];
 527
 528                 cert = SSL_get_peer_certificate(sess);
 529
 530                 if (!cert)
 531                 {
 532                         certinfo->error = "Could not get peer certificate: "+std::string(get_error());
 533                         return;
 534                 }
 535
 536                 certinfo->invalid = (SSL_get_verify_result(sess) != X509_V_OK);
 537
 538                 if (!SelfSigned)
 539                 {
 540                         certinfo->unknownsigner = false;
 541                         certinfo->trusted = true;
 542                 }
 543                 else
 544                 {
 545                         certinfo->unknownsigner = true;
 546                         certinfo->trusted = false;
 547                 }
 548
 549                 char buf[512];
 550                 X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
 551                 certinfo->dn = buf;
 552                 // Make sure there are no chars in the string that we consider invalid
 553                 if (certinfo->dn.find_first_of("\r\n") != std::string::npos)
 554                         certinfo->dn.clear();
 555
 556                 X509_NAME_oneline(X509_get_issuer_name(cert), buf, sizeof(buf));
 557                 certinfo->issuer = buf;
 558                 if (certinfo->issuer.find_first_of("\r\n") != std::string::npos)
 559                         certinfo->issuer.clear();
 560
 561                 if (!X509_digest(cert, GetProfile().GetDigest(), md, &n))
 562                 {
 563                         certinfo->error = "Out of memory generating fingerprint";
 564                 }
 565                 else
 566                 {
 567                         certinfo->fingerprint = BinToHex(md, n);
 568                 }
 569
 570                 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))
 571                 {
 572                         certinfo->error = "Not activated, or expired certificate";
 573                 }
 574
 575                 X509_free(cert);
 576         }
 577
 578         void SSLInfoCallback(int where, int rc)
 579         {
 580                 if ((where & SSL_CB_HANDSHAKE_START) && (status == ISSL_OPEN))
 581                 {
 582                         if (GetProfile().AllowRenegotiation())
 583                                 return;
 584
 585                         // The other side is trying to renegotiate, kill the connection and change status
 586                         // to ISSL_NONE so CheckRenego() closes the session
 587                         status = ISSL_NONE;
 588                         BIO* bio = SSL_get_rbio(sess);
 589                         EventHandler* eh = static_cast<StreamSocket*>(BIO_get_data(bio));
 590                         SocketEngine::Shutdown(eh, 2);
 591                 }
 592         }
 593
 594         bool CheckRenego(StreamSocket* sock)
 595         {
 596                 if (status != ISSL_NONE)
 597                         return true;
 598
 599                 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Session %p killed, attempted to renegotiate", (void*)sess);
 600                 CloseSession();
 601                 sock->SetError("Renegotiation is not allowed");
 602                 return false;
 603         }
 604
 605         // Returns 1 if application I/O should proceed, 0 if it must wait for the underlying protocol to progress, -1 on fatal error
 606         int PrepareIO(StreamSocket* sock)
 607         {
 608                 if (status == ISSL_OPEN)
 609                         return 1;
 610                 else if (status == ISSL_HANDSHAKING)
 611                 {
 612                         // The handshake isn't finished, try to finish it
 613                         return Handshake(sock);
 614                 }
 615
 616                 CloseSession();
 617                 return -1;
 618         }
 619
 620         // Calls our private SSLInfoCallback()
 621         friend void StaticSSLInfoCallback(const SSL* ssl, int where, int rc);
 622
 623  public:
 624         OpenSSLIOHook(IOHookProvider* hookprov, StreamSocket* sock, SSL* session)
 625                 : SSLIOHook(hookprov)
 626                 , sess(session)
 627                 , status(ISSL_NONE)
 628                 , data_to_write(false)
 629         {
 630                 // Create BIO instance and store a pointer to the socket in it which will be used by the read and write functions
 631 #ifdef INSPIRCD_OPENSSL_OPAQUE_BIO
 632                 BIO* bio = BIO_new(biomethods);
 633 #else
 634                 BIO* bio = BIO_new(&biomethods);
 635 #endif
 636                 BIO_set_data(bio, sock);
 637                 SSL_set_bio(sess, bio, bio);
 638
 639                 SSL_set_ex_data(sess, exdataindex, this);
 640                 sock->AddIOHook(this);
 641                 Handshake(sock);
 642         }
 643
 644         void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE
 645         {
 646                 CloseSession();
 647         }
 648
 649         int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE
 650         {
 651                 // Finish handshake if needed
 652                 int prepret = PrepareIO(user);
 653                 if (prepret <= 0)
 654                         return prepret;
 655
 656                 // If we resumed the handshake then this->status will be ISSL_OPEN
 657                 {
 658                         ERR_clear_error();
 659                         char* buffer = ServerInstance->GetReadBuffer();
 660                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 661                         int ret = SSL_read(sess, buffer, bufsiz);
 662
 663                         if (!CheckRenego(user))
 664                                 return -1;
 665
 666                         if (ret > 0)
 667                         {
 668                                 recvq.append(buffer, ret);
 669                                 int mask = 0;
 670                                 // Schedule a read if there is still data in the OpenSSL buffer
 671                                 if (SSL_pending(sess) > 0)
 672                                         mask |= FD_ADD_TRIAL_READ;
 673                                 if (data_to_write)
 674                                         mask |= FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE;
 675                                 if (mask != 0)
 676                                         SocketEngine::ChangeEventMask(user, mask);
 677                                 return 1;
 678                         }
 679                         else if (ret == 0)
 680                         {
 681                                 // Client closed connection.
 682                                 CloseSession();
 683                                 user->SetError("Connection closed");
 684                                 return -1;
 685                         }
 686                         else // if (ret < 0)
 687                         {
 688                                 int err = SSL_get_error(sess, ret);
 689
 690                                 if (err == SSL_ERROR_WANT_READ)
 691                                 {
 692                                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ);
 693                                         return 0;
 694                                 }
 695                                 else if (err == SSL_ERROR_WANT_WRITE)
 696                                 {
 697                                         SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 698                                         return 0;
 699                                 }
 700                                 else
 701                                 {
 702                                         CloseSession();
 703                                         return -1;
 704                                 }
 705                         }
 706                 }
 707         }
 708
 709         int OnStreamSocketWrite(StreamSocket* user, StreamSocket::SendQueue& sendq) CXX11_OVERRIDE
 710         {
 711                 // Finish handshake if needed
 712                 int prepret = PrepareIO(user);
 713                 if (prepret <= 0)
 714                         return prepret;
 715
 716                 data_to_write = true;
 717
 718                 // Session is ready for transferring application data
 719                 while (!sendq.empty())
 720                 {
 721                         ERR_clear_error();
 722                         FlattenSendQueue(sendq, GetProfile().GetOutgoingRecordSize());
 723                         const StreamSocket::SendQueue::Element& buffer = sendq.front();
 724                         int ret = SSL_write(sess, buffer.data(), buffer.size());
 725
 726                         if (!CheckRenego(user))
 727                                 return -1;
 728
 729                         if (ret == (int)buffer.length())
 730                         {
 731                                 // Wrote entire record, continue sending
 732                                 sendq.pop_front();
 733                         }
 734                         else if (ret > 0)
 735                         {
 736                                 sendq.erase_front(ret);
 737                                 SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 738                                 return 0;
 739                         }
 740                         else if (ret == 0)
 741                         {
 742                                 CloseSession();
 743                                 return -1;
 744                         }
 745                         else // if (ret < 0)
 746                         {
 747                                 int err = SSL_get_error(sess, ret);
 748
 749                                 if (err == SSL_ERROR_WANT_WRITE)
 750                                 {
 751                                         SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 752                                         return 0;
 753                                 }
 754                                 else if (err == SSL_ERROR_WANT_READ)
 755                                 {
 756                                         SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ);
 757                                         return 0;
 758                                 }
 759                                 else
 760                                 {
 761                                         CloseSession();
 762                                         return -1;
 763                                 }
 764                         }
 765                 }
 766
 767                 data_to_write = false;
 768                 SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 769                 return 1;
 770         }
 771
 772         void GetCiphersuite(std::string& out) const CXX11_OVERRIDE
 773         {
 774                 if (!IsHandshakeDone())
 775                         return;
 776                 out.append(SSL_get_version(sess)).push_back('-');
 777                 out.append(SSL_get_cipher(sess));
 778         }
 779
 780         bool GetServerName(std::string& out) const CXX11_OVERRIDE
 781         {
 782                 const char* name = SSL_get_servername(sess, TLSEXT_NAMETYPE_host_name);
 783                 if (!name)
 784                         return false;
 785
 786                 out.append(name);
 787                 return true;
 788         }
 789
 790         bool IsHandshakeDone() const { return (status == ISSL_OPEN); }
 791         OpenSSL::Profile& GetProfile();
 792 };
 793
 794 static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc)
 795 {
 796         OpenSSLIOHook* hook = static_cast<OpenSSLIOHook*>(SSL_get_ex_data(ssl, exdataindex));
 797         hook->SSLInfoCallback(where, rc);
 798 }
 799
 800 static int OpenSSL::BIOMethod::write(BIO* bio, const char* buffer, int size)
 801 {
 802         BIO_clear_retry_flags(bio);
 803
 804         StreamSocket* sock = static_cast<StreamSocket*>(BIO_get_data(bio));
 805         if (sock->GetEventMask() & FD_WRITE_WILL_BLOCK)
 806         {
 807                 // Writes blocked earlier, don't retry syscall
 808                 BIO_set_retry_write(bio);
 809                 return -1;
 810         }
 811
 812         int ret = SocketEngine::Send(sock, buffer, size, 0);
 813         if ((ret < size) && ((ret > 0) || (SocketEngine::IgnoreError())))
 814         {
 815                 // Blocked, set retry flag for OpenSSL
 816                 SocketEngine::ChangeEventMask(sock, FD_WRITE_WILL_BLOCK);
 817                 BIO_set_retry_write(bio);
 818         }
 819
 820         return ret;
 821 }
 822
 823 static int OpenSSL::BIOMethod::read(BIO* bio, char* buffer, int size)
 824 {
 825         BIO_clear_retry_flags(bio);
 826
 827         StreamSocket* sock = static_cast<StreamSocket*>(BIO_get_data(bio));
 828         if (sock->GetEventMask() & FD_READ_WILL_BLOCK)
 829         {
 830                 // Reads blocked earlier, don't retry syscall
 831                 BIO_set_retry_read(bio);
 832                 return -1;
 833         }
 834
 835         int ret = SocketEngine::Recv(sock, buffer, size, 0);
 836         if ((ret < size) && ((ret > 0) || (SocketEngine::IgnoreError())))
 837         {
 838                 // Blocked, set retry flag for OpenSSL
 839                 SocketEngine::ChangeEventMask(sock, FD_READ_WILL_BLOCK);
 840                 BIO_set_retry_read(bio);
 841         }
 842
 843         return ret;
 844 }
 845
 846 class OpenSSLIOHookProvider : public IOHookProvider
 847 {
 848         OpenSSL::Profile profile;
 849
 850  public:
 851         OpenSSLIOHookProvider(Module* mod, const std::string& profilename, ConfigTag* tag)
 852                 : IOHookProvider(mod, "ssl/" + profilename, IOHookProvider::IOH_SSL)
 853                 , profile(profilename, tag)
 854         {
 855                 ServerInstance->Modules->AddService(*this);
 856         }
 857
 858         ~OpenSSLIOHookProvider()
 859         {
 860                 ServerInstance->Modules->DelService(*this);
 861         }
 862
 863         void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE
 864         {
 865                 new OpenSSLIOHook(this, sock, profile.CreateServerSession());
 866         }
 867
 868         void OnConnect(StreamSocket* sock) CXX11_OVERRIDE
 869         {
 870                 new OpenSSLIOHook(this, sock, profile.CreateClientSession());
 871         }
 872
 873         OpenSSL::Profile& GetProfile() { return profile; }
 874 };
 875
 876 OpenSSL::Profile& OpenSSLIOHook::GetProfile()
 877 {
 878         IOHookProvider* hookprov = prov;
 879         return static_cast<OpenSSLIOHookProvider*>(hookprov)->GetProfile();
 880 }
 881
 882 class ModuleSSLOpenSSL : public Module
 883 {
 884         typedef std::vector<reference<OpenSSLIOHookProvider> > ProfileList;
 885
 886         ProfileList profiles;
 887
 888         void ReadProfiles()
 889         {
 890                 ProfileList newprofiles;
 891                 ConfigTagList tags = ServerInstance->Config->ConfTags("sslprofile");
 892                 if (tags.first == tags.second)
 893                 {
 894                         // Create a default profile named "openssl"
 895                         const std::string defname = "openssl";
 896                         ConfigTag* tag = ServerInstance->Config->ConfValue(defname);
 897                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "No <sslprofile> tags found, using settings from the <openssl> tag");
 898
 899                         try
 900                         {
 901                                 newprofiles.push_back(new OpenSSLIOHookProvider(this, defname, tag));
 902                         }
 903                         catch (OpenSSL::Exception& ex)
 904                         {
 905                                 throw ModuleException("Error while initializing the default SSL profile - " + ex.GetReason());
 906                         }
 907                 }
 908
 909                 for (ConfigIter i = tags.first; i != tags.second; ++i)
 910                 {
 911                         ConfigTag* tag = i->second;
 912                         if (tag->getString("provider") != "openssl")
 913                                 continue;
 914
 915                         std::string name = tag->getString("name");
 916                         if (name.empty())
 917                         {
 918                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Ignoring <sslprofile> tag without name at " + tag->getTagLocation());
 919                                 continue;
 920                         }
 921
 922                         reference<OpenSSLIOHookProvider> prov;
 923                         try
 924                         {
 925                                 prov = new OpenSSLIOHookProvider(this, name, tag);
 926                         }
 927                         catch (CoreException& ex)
 928                         {
 929                                 throw ModuleException("Error while initializing SSL profile \"" + name + "\" at " + tag->getTagLocation() + " - " + ex.GetReason());
 930                         }
 931
 932                         newprofiles.push_back(prov);
 933                 }
 934
 935                 for (ProfileList::iterator i = profiles.begin(); i != profiles.end(); ++i)
 936                 {
 937                         OpenSSLIOHookProvider& prov = **i;
 938                         ServerInstance->Modules.DelService(prov);
 939                 }
 940
 941                 profiles.swap(newprofiles);
 942         }
 943
 944  public:
 945         ModuleSSLOpenSSL()
 946         {
 947                 // Initialize OpenSSL
 948                 SSL_library_init();
 949                 SSL_load_error_strings();
 950 #ifdef INSPIRCD_OPENSSL_OPAQUE_BIO
 951                 biomethods = OpenSSL::BIOMethod::alloc();
 952         }
 953
 954         ~ModuleSSLOpenSSL()
 955         {
 956                 BIO_meth_free(biomethods);
 957 #endif
 958         }
 959
 960         void init() CXX11_OVERRIDE
 961         {
 962                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "OpenSSL lib version \"%s\" module was compiled for \"" OPENSSL_VERSION_TEXT "\"", SSLeay_version(SSLEAY_VERSION));
 963
 964                 // Register application specific data
 965                 char exdatastr[] = "inspircd";
 966                 exdataindex = SSL_get_ex_new_index(0, exdatastr, NULL, NULL, NULL);
 967                 if (exdataindex < 0)
 968                         throw ModuleException("Failed to register application specific data");
 969
 970                 ReadProfiles();
 971         }
 972
 973         void OnModuleRehash(User* user, const std::string &param) CXX11_OVERRIDE
 974         {
 975                 if (param != "ssl")
 976                         return;
 977
 978                 try
 979                 {
 980                         ReadProfiles();
 981                 }
 982                 catch (ModuleException& ex)
 983                 {
 984                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, ex.GetReason() + " Not applying settings.");
 985                 }
 986         }
 987
 988         void OnCleanup(ExtensionItem::ExtensibleType type, Extensible* item) CXX11_OVERRIDE
 989         {
 990                 if (type == ExtensionItem::EXT_USER)
 991                 {
 992                         LocalUser* user = IS_LOCAL((User*)item);
 993
 994                         if ((user) && (user->eh.GetModHook(this)))
 995                         {
 996                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 997                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 998                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 999                         }
1000                 }
1001         }
1002
1003         ModResult OnCheckReady(LocalUser* user) CXX11_OVERRIDE
1004         {
1005                 const OpenSSLIOHook* const iohook = static_cast<OpenSSLIOHook*>(user->eh.GetModHook(this));
1006                 if ((iohook) && (!iohook->IsHandshakeDone()))
1007                         return MOD_RES_DENY;
1008                 return MOD_RES_PASSTHRU;
1009         }
1010
1011         Version GetVersion() CXX11_OVERRIDE
1012         {
1013                 return Version("Provides SSL support for clients", VF_VENDOR);
1014         }
1015 };
1016
1017 MODULE_INIT(ModuleSSLOpenSSL)