src/modules/extra/m_ssl_gnutls.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
   5  *   Copyright (C) 2008 John Brooks <john.brooks@dereferenced.net>
   6  *   Copyright (C) 2006-2008 Craig Edwards <craigedwards@brainbox.cc>
   7  *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
   8  *   Copyright (C) 2006 Oliver Lupton <oliverlupton@gmail.com>
   9  *
  10  * This file is part of InspIRCd.  InspIRCd is free software: you can
  11  * redistribute it and/or modify it under the terms of the GNU General Public
  12  * License as published by the Free Software Foundation, version 2.
  13  *
  14  * This program is distributed in the hope that it will be useful, but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  16  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  17  * details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23
  24 #include "inspircd.h"
  25 #include <gnutls/gnutls.h>
  26 #include <gnutls/x509.h>
  27 #include "modules/ssl.h"
  28 #include "modules/cap.h"
  29 #include <memory>
  30
  31 #if ((GNUTLS_VERSION_MAJOR > 2) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 9) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR == 9 && GNUTLS_VERSION_PATCH >= 8))
  32 #define GNUTLS_HAS_MAC_GET_ID
  33 #include <gnutls/crypto.h>
  34 #endif
  35
  36 #if (GNUTLS_VERSION_MAJOR > 2 || GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 12)
  37 # define GNUTLS_HAS_RND
  38 #else
  39 # include <gcrypt.h>
  40 #endif
  41
  42 #ifdef _WIN32
  43 # pragma comment(lib, "libgnutls.lib")
  44 # pragma comment(lib, "libgcrypt.lib")
  45 # pragma comment(lib, "libgpg-error.lib")
  46 # pragma comment(lib, "user32.lib")
  47 # pragma comment(lib, "advapi32.lib")
  48 # pragma comment(lib, "libgcc.lib")
  49 # pragma comment(lib, "libmingwex.lib")
  50 # pragma comment(lib, "gdi32.lib")
  51 #endif
  52
  53 /* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") eval("print `libgcrypt-config --cflags | tr -d \r` if `pkg-config --modversion gnutls 2>/dev/null | tr -d \r` lt '2.12'") -Wno-pedantic */
  54 /* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") eval("print `libgcrypt-config --libs | tr -d \r` if `pkg-config --modversion gnutls 2>/dev/null | tr -d \r` lt '2.12'") */
  55
  56 #ifndef GNUTLS_VERSION_MAJOR
  57 #define GNUTLS_VERSION_MAJOR LIBGNUTLS_VERSION_MAJOR
  58 #define GNUTLS_VERSION_MINOR LIBGNUTLS_VERSION_MINOR
  59 #define GNUTLS_VERSION_PATCH LIBGNUTLS_VERSION_PATCH
  60 #endif
  61
  62 // These don't exist in older GnuTLS versions
  63 #if ((GNUTLS_VERSION_MAJOR > 2) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 1) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR == 1 && GNUTLS_VERSION_PATCH >= 7))
  64 #define GNUTLS_NEW_PRIO_API
  65 #endif
  66
  67 #if(GNUTLS_VERSION_MAJOR < 2)
  68 typedef gnutls_certificate_credentials_t gnutls_certificate_credentials;
  69 typedef gnutls_dh_params_t gnutls_dh_params;
  70 #endif
  71
  72 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  73
  74 #if (GNUTLS_VERSION_MAJOR > 2 || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR >= 12))
  75 #define GNUTLS_NEW_CERT_CALLBACK_API
  76 typedef gnutls_retr2_st cert_cb_last_param_type;
  77 #else
  78 typedef gnutls_retr_st cert_cb_last_param_type;
  79 #endif
  80
  81 class RandGen : public HandlerBase2<void, char*, size_t>
  82 {
  83  public:
  84         RandGen() {}
  85         void Call(char* buffer, size_t len)
  86         {
  87 #ifdef GNUTLS_HAS_RND
  88                 gnutls_rnd(GNUTLS_RND_RANDOM, buffer, len);
  89 #else
  90                 gcry_randomize(buffer, len, GCRY_STRONG_RANDOM);
  91 #endif
  92         }
  93 };
  94
  95 namespace GnuTLS
  96 {
  97         class Init
  98         {
  99          public:
 100                 Init() { gnutls_global_init(); }
 101                 ~Init() { gnutls_global_deinit(); }
 102         };
 103
 104         class Exception : public ModuleException
 105         {
 106          public:
 107                 Exception(const std::string& reason)
 108                         : ModuleException(reason) { }
 109         };
 110
 111         void ThrowOnError(int errcode, const char* msg)
 112         {
 113                 if (errcode < 0)
 114                 {
 115                         std::string reason = msg;
 116                         reason.append(" :").append(gnutls_strerror(errcode));
 117                         throw Exception(reason);
 118                 }
 119         }
 120
 121         /** Used to create a gnutls_datum_t* from a std::string
 122          */
 123         class Datum
 124         {
 125                 gnutls_datum_t datum;
 126
 127          public:
 128                 Datum(const std::string& dat)
 129                 {
 130                         datum.data = (unsigned char*)dat.data();
 131                         datum.size = static_cast<unsigned int>(dat.length());
 132                 }
 133
 134                 const gnutls_datum_t* get() const { return &datum; }
 135         };
 136
 137         class Hash
 138         {
 139                 gnutls_digest_algorithm_t hash;
 140
 141          public:
 142                 // Nothing to deallocate, constructor may throw freely
 143                 Hash(const std::string& hashname)
 144                 {
 145                         // As older versions of gnutls can't do this, let's disable it where needed.
 146 #ifdef GNUTLS_HAS_MAC_GET_ID
 147                         // As gnutls_digest_algorithm_t and gnutls_mac_algorithm_t are mapped 1:1, we can do this
 148                         // There is no gnutls_dig_get_id() at the moment, but it may come later
 149                         hash = (gnutls_digest_algorithm_t)gnutls_mac_get_id(hashname.c_str());
 150                         if (hash == GNUTLS_DIG_UNKNOWN)
 151                                 throw Exception("Unknown hash type " + hashname);
 152
 153                         // Check if the user is giving us something that is a valid MAC but not digest
 154                         gnutls_hash_hd_t is_digest;
 155                         if (gnutls_hash_init(&is_digest, hash) < 0)
 156                                 throw Exception("Unknown hash type " + hashname);
 157                         gnutls_hash_deinit(is_digest, NULL);
 158 #else
 159                         if (hashname == "md5")
 160                                 hash = GNUTLS_DIG_MD5;
 161                         else if (hashname == "sha1")
 162                                 hash = GNUTLS_DIG_SHA1;
 163                         else
 164                                 throw Exception("Unknown hash type " + hashname);
 165 #endif
 166                 }
 167
 168                 gnutls_digest_algorithm_t get() const { return hash; }
 169         };
 170
 171         class DHParams
 172         {
 173                 gnutls_dh_params_t dh_params;
 174
 175                 DHParams()
 176                 {
 177                         ThrowOnError(gnutls_dh_params_init(&dh_params), "gnutls_dh_params_init() failed");
 178                 }
 179
 180          public:
 181                 /** Import */
 182                 static std::auto_ptr<DHParams> Import(const std::string& dhstr)
 183                 {
 184                         std::auto_ptr<DHParams> dh(new DHParams);
 185                         int ret = gnutls_dh_params_import_pkcs3(dh->dh_params, Datum(dhstr).get(), GNUTLS_X509_FMT_PEM);
 186                         ThrowOnError(ret, "Unable to import DH params");
 187                         return dh;
 188                 }
 189
 190                 /** Generate */
 191                 static std::auto_ptr<DHParams> Generate(unsigned int bits)
 192                 {
 193                         std::auto_ptr<DHParams> dh(new DHParams);
 194                         ThrowOnError(gnutls_dh_params_generate2(dh->dh_params, bits), "Unable to generate DH params");
 195                         return dh;
 196                 }
 197
 198                 ~DHParams()
 199                 {
 200                         gnutls_dh_params_deinit(dh_params);
 201                 }
 202
 203                 const gnutls_dh_params_t& get() const { return dh_params; }
 204         };
 205
 206         class X509Key
 207         {
 208                 /** Ensure that the key is deinited in case the constructor of X509Key throws
 209                  */
 210                 class RAIIKey
 211                 {
 212                  public:
 213                         gnutls_x509_privkey_t key;
 214
 215                         RAIIKey()
 216                         {
 217                                 ThrowOnError(gnutls_x509_privkey_init(&key), "gnutls_x509_privkey_init() failed");
 218                         }
 219
 220                         ~RAIIKey()
 221                         {
 222                                 gnutls_x509_privkey_deinit(key);
 223                         }
 224                 } key;
 225
 226          public:
 227                 /** Import */
 228                 X509Key(const std::string& keystr)
 229                 {
 230                         int ret = gnutls_x509_privkey_import(key.key, Datum(keystr).get(), GNUTLS_X509_FMT_PEM);
 231                         ThrowOnError(ret, "Unable to import private key");
 232                 }
 233
 234                 gnutls_x509_privkey_t& get() { return key.key; }
 235         };
 236
 237         class X509CertList
 238         {
 239                 std::vector<gnutls_x509_crt_t> certs;
 240
 241          public:
 242                 /** Import */
 243                 X509CertList(const std::string& certstr)
 244                 {
 245                         unsigned int certcount = 3;
 246                         certs.resize(certcount);
 247                         Datum datum(certstr);
 248
 249                         int ret = gnutls_x509_crt_list_import(raw(), &certcount, datum.get(), GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
 250                         if (ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
 251                         {
 252                                 // the buffer wasn't big enough to hold all certs but gnutls changed certcount to the number of available certs,
 253                                 // try again with a bigger buffer
 254                                 certs.resize(certcount);
 255                                 ret = gnutls_x509_crt_list_import(raw(), &certcount, datum.get(), GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
 256                         }
 257
 258                         ThrowOnError(ret, "Unable to load certificates");
 259
 260                         // Resize the vector to the actual number of certs because we rely on its size being correct
 261                         // when deallocating the certs
 262                         certs.resize(certcount);
 263                 }
 264
 265                 ~X509CertList()
 266                 {
 267                         for (std::vector<gnutls_x509_crt_t>::iterator i = certs.begin(); i != certs.end(); ++i)
 268                                 gnutls_x509_crt_deinit(*i);
 269                 }
 270
 271                 gnutls_x509_crt_t* raw() { return &certs[0]; }
 272                 unsigned int size() const { return certs.size(); }
 273         };
 274
 275         class X509CRL : public refcountbase
 276         {
 277                 class RAIICRL
 278                 {
 279                  public:
 280                         gnutls_x509_crl_t crl;
 281
 282                         RAIICRL()
 283                         {
 284                                 ThrowOnError(gnutls_x509_crl_init(&crl), "gnutls_x509_crl_init() failed");
 285                         }
 286
 287                         ~RAIICRL()
 288                         {
 289                                 gnutls_x509_crl_deinit(crl);
 290                         }
 291                 } crl;
 292
 293          public:
 294                 /** Import */
 295                 X509CRL(const std::string& crlstr)
 296                 {
 297                         int ret = gnutls_x509_crl_import(get(), Datum(crlstr).get(), GNUTLS_X509_FMT_PEM);
 298                         ThrowOnError(ret, "Unable to load certificate revocation list");
 299                 }
 300
 301                 gnutls_x509_crl_t& get() { return crl.crl; }
 302         };
 303
 304 #ifdef GNUTLS_NEW_PRIO_API
 305         class Priority
 306         {
 307                 gnutls_priority_t priority;
 308
 309          public:
 310                 Priority(const std::string& priorities)
 311                 {
 312                         // Try to set the priorities for ciphers, kex methods etc. to the user supplied string
 313                         // If the user did not supply anything then the string is already set to "NORMAL"
 314                         const char* priocstr = priorities.c_str();
 315                         const char* prioerror;
 316
 317                         int ret = gnutls_priority_init(&priority, priocstr, &prioerror);
 318                         if (ret < 0)
 319                         {
 320                                 // gnutls did not understand the user supplied string
 321                                 throw Exception("Unable to initialize priorities to \"" + priorities + "\": " + gnutls_strerror(ret) + " Syntax error at position " + ConvToStr((unsigned int) (prioerror - priocstr)));
 322                         }
 323                 }
 324
 325                 ~Priority()
 326                 {
 327                         gnutls_priority_deinit(priority);
 328                 }
 329
 330                 void SetupSession(gnutls_session_t sess)
 331                 {
 332                         gnutls_priority_set(sess, priority);
 333                 }
 334         };
 335 #else
 336         /** Dummy class, used when gnutls_priority_set() is not available
 337          */
 338         class Priority
 339         {
 340          public:
 341                 Priority(const std::string& priorities)
 342                 {
 343                         if (priorities != "NORMAL")
 344                                 throw Exception("You've set a non-default priority string, but GnuTLS lacks support for it");
 345                 }
 346
 347                 static void SetupSession(gnutls_session_t sess)
 348                 {
 349                         // Always set the default priorities
 350                         gnutls_set_default_priority(sess);
 351                 }
 352         };
 353 #endif
 354
 355         class CertCredentials
 356         {
 357                 /** DH parameters associated with these credentials
 358                  */
 359                 std::auto_ptr<DHParams> dh;
 360
 361          protected:
 362                 gnutls_certificate_credentials_t cred;
 363
 364          public:
 365                 CertCredentials()
 366                 {
 367                         ThrowOnError(gnutls_certificate_allocate_credentials(&cred), "Cannot allocate certificate credentials");
 368                 }
 369
 370                 ~CertCredentials()
 371                 {
 372                         gnutls_certificate_free_credentials(cred);
 373                 }
 374
 375                 /** Associates these credentials with the session
 376                  */
 377                 void SetupSession(gnutls_session_t sess)
 378                 {
 379                         gnutls_credentials_set(sess, GNUTLS_CRD_CERTIFICATE, cred);
 380                 }
 381
 382                 /** Set the given DH parameters to be used with these credentials
 383                  */
 384                 void SetDH(std::auto_ptr<DHParams>& DH)
 385                 {
 386                         dh = DH;
 387                         gnutls_certificate_set_dh_params(cred, dh->get());
 388                 }
 389         };
 390
 391         class X509Credentials : public CertCredentials
 392         {
 393                 /** Private key
 394                  */
 395                 X509Key key;
 396
 397                 /** Certificate list, presented to the peer
 398                  */
 399                 X509CertList certs;
 400
 401                 /** Trusted CA, may be NULL
 402                  */
 403                 std::auto_ptr<X509CertList> trustedca;
 404
 405                 /** Certificate revocation list, may be NULL
 406                  */
 407                 std::auto_ptr<X509CRL> crl;
 408
 409                 static int cert_callback(gnutls_session_t session, const gnutls_datum_t* req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t* sign_algos, int sign_algos_length, cert_cb_last_param_type* st);
 410
 411          public:
 412                 X509Credentials(const std::string& certstr, const std::string& keystr)
 413                         : key(keystr)
 414                         , certs(certstr)
 415                 {
 416                         // Throwing is ok here, the destructor of Credentials is called in that case
 417                         int ret = gnutls_certificate_set_x509_key(cred, certs.raw(), certs.size(), key.get());
 418                         ThrowOnError(ret, "Unable to set cert/key pair");
 419
 420 #ifdef GNUTLS_NEW_CERT_CALLBACK_API
 421                         gnutls_certificate_set_retrieve_function(cred, cert_callback);
 422 #else
 423                         gnutls_certificate_client_set_retrieve_function(cred, cert_callback);
 424 #endif
 425                 }
 426
 427                 /** Sets the trusted CA and the certificate revocation list
 428                  * to use when verifying certificates
 429                  */
 430                 void SetCA(std::auto_ptr<X509CertList>& certlist, std::auto_ptr<X509CRL>& CRL)
 431                 {
 432                         // Do nothing if certlist is NULL
 433                         if (certlist.get())
 434                         {
 435                                 int ret = gnutls_certificate_set_x509_trust(cred, certlist->raw(), certlist->size());
 436                                 ThrowOnError(ret, "gnutls_certificate_set_x509_trust() failed");
 437
 438                                 if (CRL.get())
 439                                 {
 440                                         ret = gnutls_certificate_set_x509_crl(cred, &CRL->get(), 1);
 441                                         ThrowOnError(ret, "gnutls_certificate_set_x509_crl() failed");
 442                                 }
 443
 444                                 trustedca = certlist;
 445                                 crl = CRL;
 446                         }
 447                 }
 448         };
 449
 450         class Profile : public refcountbase
 451         {
 452                 /** Name of this profile
 453                  */
 454                 const std::string name;
 455
 456                 /** X509 certificate(s) and key
 457                  */
 458                 X509Credentials x509cred;
 459
 460                 /** The minimum length in bits for the DH prime to be accepted as a client
 461                  */
 462                 unsigned int min_dh_bits;
 463
 464                 /** Hashing algorithm to use when generating certificate fingerprints
 465                  */
 466                 Hash hash;
 467
 468                 /** Priorities for ciphers, compression methods, etc.
 469                  */
 470                 Priority priority;
 471
 472                 Profile(const std::string& profilename, const std::string& certstr, const std::string& keystr,
 473                                 std::auto_ptr<DHParams>& DH, unsigned int mindh, const std::string& hashstr,
 474                                 const std::string& priostr, std::auto_ptr<X509CertList>& CA, std::auto_ptr<X509CRL>& CRL)
 475                         : name(profilename)
 476                         , x509cred(certstr, keystr)
 477                         , min_dh_bits(mindh)
 478                         , hash(hashstr)
 479                         , priority(priostr)
 480                 {
 481                         x509cred.SetDH(DH);
 482                         x509cred.SetCA(CA, CRL);
 483                 }
 484
 485                 static std::string ReadFile(const std::string& filename)
 486                 {
 487                         FileReader reader(filename);
 488                         std::string ret = reader.GetString();
 489                         if (ret.empty())
 490                                 throw Exception("Cannot read file " + filename);
 491                         return ret;
 492                 }
 493
 494          public:
 495                 static reference<Profile> Create(const std::string& profilename, ConfigTag* tag)
 496                 {
 497                         std::string certstr = ReadFile(tag->getString("certfile", "cert.pem"));
 498                         std::string keystr = ReadFile(tag->getString("keyfile", "key.pem"));
 499
 500                         std::auto_ptr<DHParams> dh;
 501                         int gendh = tag->getInt("gendh");
 502                         if (gendh)
 503                         {
 504                                 gendh = (gendh < 1024 ? 1024 : gendh);
 505                                 dh = DHParams::Generate(gendh);
 506                         }
 507                         else
 508                                 dh = DHParams::Import(ReadFile(tag->getString("dhfile", "dhparams.pem")));
 509
 510                         // Use default priority string if this tag does not specify one
 511                         std::string priostr = tag->getString("priority", "NORMAL");
 512                         unsigned int mindh = tag->getInt("mindhbits", 1024);
 513                         std::string hashstr = tag->getString("hash", "md5");
 514
 515                         // Load trusted CA and revocation list, if set
 516                         std::auto_ptr<X509CertList> ca;
 517                         std::auto_ptr<X509CRL> crl;
 518                         std::string filename = tag->getString("cafile");
 519                         if (!filename.empty())
 520                         {
 521                                 ca.reset(new X509CertList(ReadFile(filename)));
 522
 523                                 filename = tag->getString("crlfile");
 524                                 if (!filename.empty())
 525                                         crl.reset(new X509CRL(ReadFile(filename)));
 526                         }
 527
 528                         return new Profile(profilename, certstr, keystr, dh, mindh, hashstr, priostr, ca, crl);
 529                 }
 530
 531                 /** Set up the given session with the settings in this profile
 532                  */
 533                 void SetupSession(gnutls_session_t sess)
 534                 {
 535                         priority.SetupSession(sess);
 536                         x509cred.SetupSession(sess);
 537                         gnutls_dh_set_prime_bits(sess, min_dh_bits);
 538                 }
 539
 540                 const std::string& GetName() const { return name; }
 541                 X509Credentials& GetX509Credentials() { return x509cred; }
 542                 gnutls_digest_algorithm_t GetHash() const { return hash.get(); }
 543         };
 544 }
 545
 546 class GnuTLSIOHook : public SSLIOHook
 547 {
 548  private:
 549         gnutls_session_t sess;
 550         issl_status status;
 551         reference<GnuTLS::Profile> profile;
 552
 553         void InitSession(StreamSocket* user, bool me_server)
 554         {
 555                 gnutls_init(&sess, me_server ? GNUTLS_SERVER : GNUTLS_CLIENT);
 556
 557                 profile->SetupSession(sess);
 558                 gnutls_transport_set_ptr(sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
 559                 gnutls_transport_set_push_function(sess, gnutls_push_wrapper);
 560                 gnutls_transport_set_pull_function(sess, gnutls_pull_wrapper);
 561
 562                 if (me_server)
 563                         gnutls_certificate_server_set_request(sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 564         }
 565
 566         void CloseSession()
 567         {
 568                 if (this->sess)
 569                 {
 570                         gnutls_bye(this->sess, GNUTLS_SHUT_WR);
 571                         gnutls_deinit(this->sess);
 572                 }
 573                 sess = NULL;
 574                 certificate = NULL;
 575                 status = ISSL_NONE;
 576         }
 577
 578         bool Handshake(StreamSocket* user)
 579         {
 580                 int ret = gnutls_handshake(this->sess);
 581
 582                 if (ret < 0)
 583                 {
 584                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 585                         {
 586                                 // Handshake needs resuming later, read() or write() would have blocked.
 587
 588                                 if (gnutls_record_get_direction(this->sess) == 0)
 589                                 {
 590                                         // gnutls_handshake() wants to read() again.
 591                                         this->status = ISSL_HANDSHAKING_READ;
 592                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
 593                                 }
 594                                 else
 595                                 {
 596                                         // gnutls_handshake() wants to write() again.
 597                                         this->status = ISSL_HANDSHAKING_WRITE;
 598                                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
 599                                 }
 600                         }
 601                         else
 602                         {
 603                                 user->SetError("Handshake Failed - " + std::string(gnutls_strerror(ret)));
 604                                 CloseSession();
 605                                 this->status = ISSL_CLOSING;
 606                         }
 607
 608                         return false;
 609                 }
 610                 else
 611                 {
 612                         // Change the seesion state
 613                         this->status = ISSL_HANDSHAKEN;
 614
 615                         VerifyCertificate();
 616
 617                         // Finish writing, if any left
 618                         ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 619
 620                         return true;
 621                 }
 622         }
 623
 624         void VerifyCertificate()
 625         {
 626                 unsigned int certstatus;
 627                 const gnutls_datum_t* cert_list;
 628                 int ret;
 629                 unsigned int cert_list_size;
 630                 gnutls_x509_crt_t cert;
 631                 char str[512];
 632                 unsigned char digest[512];
 633                 size_t digest_size = sizeof(digest);
 634                 size_t name_size = sizeof(str);
 635                 ssl_cert* certinfo = new ssl_cert;
 636                 this->certificate = certinfo;
 637
 638                 /* This verification function uses the trusted CAs in the credentials
 639                  * structure. So you must have installed one or more CA certificates.
 640                  */
 641                 ret = gnutls_certificate_verify_peers2(this->sess, &certstatus);
 642
 643                 if (ret < 0)
 644                 {
 645                         certinfo->error = std::string(gnutls_strerror(ret));
 646                         return;
 647                 }
 648
 649                 certinfo->invalid = (certstatus & GNUTLS_CERT_INVALID);
 650                 certinfo->unknownsigner = (certstatus & GNUTLS_CERT_SIGNER_NOT_FOUND);
 651                 certinfo->revoked = (certstatus & GNUTLS_CERT_REVOKED);
 652                 certinfo->trusted = !(certstatus & GNUTLS_CERT_SIGNER_NOT_CA);
 653
 654                 /* Up to here the process is the same for X.509 certificates and
 655                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 656                  * be easily extended to work with openpgp keys as well.
 657                  */
 658                 if (gnutls_certificate_type_get(this->sess) != GNUTLS_CRT_X509)
 659                 {
 660                         certinfo->error = "No X509 keys sent";
 661                         return;
 662                 }
 663
 664                 ret = gnutls_x509_crt_init(&cert);
 665                 if (ret < 0)
 666                 {
 667                         certinfo->error = gnutls_strerror(ret);
 668                         return;
 669                 }
 670
 671                 cert_list_size = 0;
 672                 cert_list = gnutls_certificate_get_peers(this->sess, &cert_list_size);
 673                 if (cert_list == NULL)
 674                 {
 675                         certinfo->error = "No certificate was found";
 676                         goto info_done_dealloc;
 677                 }
 678
 679                 /* This is not a real world example, since we only check the first
 680                  * certificate in the given chain.
 681                  */
 682
 683                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 684                 if (ret < 0)
 685                 {
 686                         certinfo->error = gnutls_strerror(ret);
 687                         goto info_done_dealloc;
 688                 }
 689
 690                 gnutls_x509_crt_get_dn(cert, str, &name_size);
 691                 certinfo->dn = str;
 692
 693                 gnutls_x509_crt_get_issuer_dn(cert, str, &name_size);
 694                 certinfo->issuer = str;
 695
 696                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, profile->GetHash(), digest, &digest_size)) < 0)
 697                 {
 698                         certinfo->error = gnutls_strerror(ret);
 699                 }
 700                 else
 701                 {
 702                         certinfo->fingerprint = BinToHex(digest, digest_size);
 703                 }
 704
 705                 /* Beware here we do not check for errors.
 706                  */
 707                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 708                 {
 709                         certinfo->error = "Not activated, or expired certificate";
 710                 }
 711
 712 info_done_dealloc:
 713                 gnutls_x509_crt_deinit(cert);
 714         }
 715
 716         static const char* UnknownIfNULL(const char* str)
 717         {
 718                 return str ? str : "UNKNOWN";
 719         }
 720
 721         static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t session_wrap, void* buffer, size_t size)
 722         {
 723                 StreamSocket* sock = reinterpret_cast<StreamSocket*>(session_wrap);
 724 #ifdef _WIN32
 725                 GnuTLSIOHook* session = static_cast<GnuTLSIOHook*>(sock->GetIOHook());
 726 #endif
 727
 728                 if (sock->GetEventMask() & FD_READ_WILL_BLOCK)
 729                 {
 730 #ifdef _WIN32
 731                         gnutls_transport_set_errno(session->sess, EAGAIN);
 732 #else
 733                         errno = EAGAIN;
 734 #endif
 735                         return -1;
 736                 }
 737
 738                 int rv = ServerInstance->SE->Recv(sock, reinterpret_cast<char *>(buffer), size, 0);
 739
 740 #ifdef _WIN32
 741                 if (rv < 0)
 742                 {
 743                         /* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
 744                          * and then set errno appropriately.
 745                          * The gnutls library may also have a different errno variable than us, see
 746                          * gnutls_transport_set_errno(3).
 747                          */
 748                         gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
 749                 }
 750 #endif
 751
 752                 if (rv < (int)size)
 753                         ServerInstance->SE->ChangeEventMask(sock, FD_READ_WILL_BLOCK);
 754                 return rv;
 755         }
 756
 757         static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t session_wrap, const void* buffer, size_t size)
 758         {
 759                 StreamSocket* sock = reinterpret_cast<StreamSocket*>(session_wrap);
 760 #ifdef _WIN32
 761                 GnuTLSIOHook* session = static_cast<GnuTLSIOHook*>(sock->GetIOHook());
 762 #endif
 763
 764                 if (sock->GetEventMask() & FD_WRITE_WILL_BLOCK)
 765                 {
 766 #ifdef _WIN32
 767                         gnutls_transport_set_errno(session->sess, EAGAIN);
 768 #else
 769                         errno = EAGAIN;
 770 #endif
 771                         return -1;
 772                 }
 773
 774                 int rv = ServerInstance->SE->Send(sock, reinterpret_cast<const char *>(buffer), size, 0);
 775
 776 #ifdef _WIN32
 777                 if (rv < 0)
 778                 {
 779                         /* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
 780                          * and then set errno appropriately.
 781                          * The gnutls library may also have a different errno variable than us, see
 782                          * gnutls_transport_set_errno(3).
 783                          */
 784                         gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
 785                 }
 786 #endif
 787
 788                 if (rv < (int)size)
 789                         ServerInstance->SE->ChangeEventMask(sock, FD_WRITE_WILL_BLOCK);
 790                 return rv;
 791         }
 792
 793  public:
 794         GnuTLSIOHook(IOHookProvider* hookprov, StreamSocket* sock, bool outbound, const reference<GnuTLS::Profile>& sslprofile)
 795                 : SSLIOHook(hookprov)
 796                 , sess(NULL)
 797                 , status(ISSL_NONE)
 798                 , profile(sslprofile)
 799         {
 800                 InitSession(sock, outbound);
 801                 sock->AddIOHook(this);
 802                 Handshake(sock);
 803         }
 804
 805         void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE
 806         {
 807                 CloseSession();
 808         }
 809
 810         int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE
 811         {
 812                 if (!this->sess)
 813                 {
 814                         CloseSession();
 815                         user->SetError("No SSL session");
 816                         return -1;
 817                 }
 818
 819                 if (this->status == ISSL_HANDSHAKING_READ || this->status == ISSL_HANDSHAKING_WRITE)
 820                 {
 821                         // The handshake isn't finished, try to finish it.
 822
 823                         if (!Handshake(user))
 824                         {
 825                                 if (this->status != ISSL_CLOSING)
 826                                         return 0;
 827                                 return -1;
 828                         }
 829                 }
 830
 831                 // If we resumed the handshake then this->status will be ISSL_HANDSHAKEN.
 832
 833                 if (this->status == ISSL_HANDSHAKEN)
 834                 {
 835                         char* buffer = ServerInstance->GetReadBuffer();
 836                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 837                         int ret = gnutls_record_recv(this->sess, buffer, bufsiz);
 838                         if (ret > 0)
 839                         {
 840                                 recvq.append(buffer, ret);
 841                                 return 1;
 842                         }
 843                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 844                         {
 845                                 return 0;
 846                         }
 847                         else if (ret == 0)
 848                         {
 849                                 user->SetError("Connection closed");
 850                                 CloseSession();
 851                                 return -1;
 852                         }
 853                         else
 854                         {
 855                                 user->SetError(gnutls_strerror(ret));
 856                                 CloseSession();
 857                                 return -1;
 858                         }
 859                 }
 860                 else if (this->status == ISSL_CLOSING)
 861                         return -1;
 862
 863                 return 0;
 864         }
 865
 866         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq) CXX11_OVERRIDE
 867         {
 868                 if (!this->sess)
 869                 {
 870                         CloseSession();
 871                         user->SetError("No SSL session");
 872                         return -1;
 873                 }
 874
 875                 if (this->status == ISSL_HANDSHAKING_WRITE || this->status == ISSL_HANDSHAKING_READ)
 876                 {
 877                         // The handshake isn't finished, try to finish it.
 878                         Handshake(user);
 879                         if (this->status != ISSL_CLOSING)
 880                                 return 0;
 881                         return -1;
 882                 }
 883
 884                 int ret = 0;
 885
 886                 if (this->status == ISSL_HANDSHAKEN)
 887                 {
 888                         ret = gnutls_record_send(this->sess, sendq.data(), sendq.length());
 889
 890                         if (ret == (int)sendq.length())
 891                         {
 892                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE);
 893                                 return 1;
 894                         }
 895                         else if (ret > 0)
 896                         {
 897                                 sendq = sendq.substr(ret);
 898                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 899                                 return 0;
 900                         }
 901                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED || ret == 0)
 902                         {
 903                                 ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 904                                 return 0;
 905                         }
 906                         else // (ret < 0)
 907                         {
 908                                 user->SetError(gnutls_strerror(ret));
 909                                 CloseSession();
 910                                 return -1;
 911                         }
 912                 }
 913
 914                 return 0;
 915         }
 916
 917         void TellCiphersAndFingerprint(LocalUser* user)
 918         {
 919                 if (sess)
 920                 {
 921                         std::string text = "*** You are connected using SSL cipher '";
 922
 923                         text += UnknownIfNULL(gnutls_kx_get_name(gnutls_kx_get(sess)));
 924                         text.append("-").append(UnknownIfNULL(gnutls_cipher_get_name(gnutls_cipher_get(sess)))).append("-");
 925                         text.append(UnknownIfNULL(gnutls_mac_get_name(gnutls_mac_get(sess)))).append("'");
 926
 927                         if (!certificate->fingerprint.empty())
 928                                 text += " and your SSL fingerprint is " + certificate->fingerprint;
 929
 930                         user->WriteNotice(text);
 931                 }
 932         }
 933
 934         GnuTLS::Profile* GetProfile() { return profile; }
 935 };
 936
 937 int GnuTLS::X509Credentials::cert_callback(gnutls_session_t sess, const gnutls_datum_t* req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t* sign_algos, int sign_algos_length, cert_cb_last_param_type* st)
 938 {
 939 #ifndef GNUTLS_NEW_CERT_CALLBACK_API
 940         st->type = GNUTLS_CRT_X509;
 941 #else
 942         st->cert_type = GNUTLS_CRT_X509;
 943         st->key_type = GNUTLS_PRIVKEY_X509;
 944 #endif
 945         StreamSocket* sock = reinterpret_cast<StreamSocket*>(gnutls_transport_get_ptr(sess));
 946         GnuTLS::X509Credentials& cred = static_cast<GnuTLSIOHook*>(sock->GetIOHook())->GetProfile()->GetX509Credentials();
 947
 948         st->ncerts = cred.certs.size();
 949         st->cert.x509 = cred.certs.raw();
 950         st->key.x509 = cred.key.get();
 951         st->deinit_all = 0;
 952
 953         return 0;
 954 }
 955
 956 class GnuTLSIOHookProvider : public refcountbase, public IOHookProvider
 957 {
 958         reference<GnuTLS::Profile> profile;
 959
 960  public:
 961         GnuTLSIOHookProvider(Module* mod, reference<GnuTLS::Profile>& prof)
 962                 : IOHookProvider(mod, "ssl/" + prof->GetName(), IOHookProvider::IOH_SSL)
 963                 , profile(prof)
 964         {
 965                 ServerInstance->Modules->AddService(*this);
 966         }
 967
 968         ~GnuTLSIOHookProvider()
 969         {
 970                 ServerInstance->Modules->DelService(*this);
 971         }
 972
 973         void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE
 974         {
 975                 new GnuTLSIOHook(this, sock, true, profile);
 976         }
 977
 978         void OnConnect(StreamSocket* sock) CXX11_OVERRIDE
 979         {
 980                 new GnuTLSIOHook(this, sock, false, profile);
 981         }
 982 };
 983
 984 class ModuleSSLGnuTLS : public Module
 985 {
 986         typedef std::vector<reference<GnuTLSIOHookProvider> > ProfileList;
 987
 988         // First member of the class, gets constructed first and destructed last
 989         GnuTLS::Init libinit;
 990
 991         std::string sslports;
 992
 993         RandGen randhandler;
 994         ProfileList profiles;
 995
 996         void ReadProfiles()
 997         {
 998                 // First, store all profiles in a new, temporary container. If no problems occur, swap the two
 999                 // containers; this way if something goes wrong we can go back and continue using the current profiles,
1000                 // avoiding unpleasant situations where no new SSL connections are possible.
1001                 ProfileList newprofiles;
1002
1003                 ConfigTagList tags = ServerInstance->Config->ConfTags("sslprofile");
1004                 if (tags.first == tags.second)
1005                 {
1006                         // No <sslprofile> tags found, create a profile named "gnutls" from settings in the <gnutls> block
1007                         const std::string defname = "gnutls";
1008                         ConfigTag* tag = ServerInstance->Config->ConfValue(defname);
1009                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "No <sslprofile> tags found; using settings from the <gnutls> tag");
1010
1011                         try
1012                         {
1013                                 reference<GnuTLS::Profile> profile(GnuTLS::Profile::Create(defname, tag));
1014                                 newprofiles.push_back(new GnuTLSIOHookProvider(this, profile));
1015                         }
1016                         catch (CoreException& ex)
1017                         {
1018                                 throw ModuleException("Error while initializing the default SSL profile - " + ex.GetReason());
1019                         }
1020                 }
1021
1022                 for (ConfigIter i = tags.first; i != tags.second; ++i)
1023                 {
1024                         ConfigTag* tag = i->second;
1025                         if (tag->getString("provider") != "gnutls")
1026                                 continue;
1027
1028                         std::string name = tag->getString("name");
1029                         if (name.empty())
1030                         {
1031                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Ignoring <sslprofile> tag without name at " + tag->getTagLocation());
1032                                 continue;
1033                         }
1034
1035                         reference<GnuTLS::Profile> profile;
1036                         try
1037                         {
1038                                 profile = GnuTLS::Profile::Create(name, tag);
1039                         }
1040                         catch (CoreException& ex)
1041                         {
1042                                 throw ModuleException("Error while initializing SSL profile \"" + name + "\" at " + tag->getTagLocation() + " - " + ex.GetReason());
1043                         }
1044
1045                         newprofiles.push_back(new GnuTLSIOHookProvider(this, profile));
1046                 }
1047
1048                 // New profiles are ok, begin using them
1049                 // Old profiles are deleted when their refcount drops to zero
1050                 profiles.swap(newprofiles);
1051         }
1052
1053  public:
1054         ModuleSSLGnuTLS()
1055         {
1056 #ifndef GNUTLS_HAS_RND
1057                 gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
1058 #endif
1059         }
1060
1061         void init() CXX11_OVERRIDE
1062         {
1063                 ReadProfiles();
1064                 ServerInstance->GenRandom = &randhandler;
1065         }
1066
1067         void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
1068         {
1069                 sslports.clear();
1070
1071                 ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
1072
1073                 if (Conf->getBool("showports", true))
1074                 {
1075                         sslports = Conf->getString("advertisedports");
1076                         if (!sslports.empty())
1077                                 return;
1078
1079                         for (size_t i = 0; i < ServerInstance->ports.size(); i++)
1080                         {
1081                                 ListenSocket* port = ServerInstance->ports[i];
1082                                 if (port->bind_tag->getString("ssl") != "gnutls")
1083                                         continue;
1084
1085                                 const std::string& portid = port->bind_desc;
1086                                 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Enabling SSL for port %s", portid.c_str());
1087
1088                                 if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
1089                                 {
1090                                         /*
1091                                          * Found an SSL port for clients that is not bound to 127.0.0.1 and handled by us, display
1092                                          * the IP:port in ISUPPORT.
1093                                          *
1094                                          * We used to advertise all ports seperated by a ';' char that matched the above criteria,
1095                                          * but this resulted in too long ISUPPORT lines if there were lots of ports to be displayed.
1096                                          * To solve this by default we now only display the first IP:port found and let the user
1097                                          * configure the exact value for the 005 token, if necessary.
1098                                          */
1099                                         sslports = portid;
1100                                         break;
1101                                 }
1102                         }
1103                 }
1104         }
1105
1106         void OnModuleRehash(User* user, const std::string &param) CXX11_OVERRIDE
1107         {
1108                 if(param != "ssl")
1109                         return;
1110
1111                 try
1112                 {
1113                         ReadProfiles();
1114                 }
1115                 catch (ModuleException& ex)
1116                 {
1117                         ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, ex.GetReason() + " Not applying settings.");
1118                 }
1119         }
1120
1121         ~ModuleSSLGnuTLS()
1122         {
1123                 ServerInstance->GenRandom = &ServerInstance->HandleGenRandom;
1124         }
1125
1126         void OnCleanup(int target_type, void* item) CXX11_OVERRIDE
1127         {
1128                 if(target_type == TYPE_USER)
1129                 {
1130                         LocalUser* user = IS_LOCAL(static_cast<User*>(item));
1131
1132                         if (user && user->eh.GetIOHook() && user->eh.GetIOHook()->prov->creator == this)
1133                         {
1134                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
1135                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
1136                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
1137                         }
1138                 }
1139         }
1140
1141         Version GetVersion() CXX11_OVERRIDE
1142         {
1143                 return Version("Provides SSL support for clients", VF_VENDOR);
1144         }
1145
1146         void On005Numeric(std::map<std::string, std::string>& tokens) CXX11_OVERRIDE
1147         {
1148                 if (!sslports.empty())
1149                         tokens["SSL"] = sslports;
1150         }
1151
1152         void OnUserConnect(LocalUser* user) CXX11_OVERRIDE
1153         {
1154                 IOHook* hook = user->eh.GetIOHook();
1155                 if (hook && hook->prov->creator == this)
1156                         static_cast<GnuTLSIOHook*>(hook)->TellCiphersAndFingerprint(user);
1157         }
1158 };
1159
1160 MODULE_INIT(ModuleSSLGnuTLS)