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