granicus.if.org Git - icinga2/blob - lib/base/tlsstream.cpp

   1 /******************************************************************************
   2  * Icinga 2                                                                   *
   3  * Copyright (C) 2012-2018 Icinga Development Team (https://icinga.com/)      *
   4  *                                                                            *
   5  * This program is free software; you can redistribute it and/or              *
   6  * modify it under the terms of the GNU General Public License                *
   7  * as published by the Free Software Foundation; either version 2             *
   8  * of the License, or (at your option) any later version.                     *
   9  *                                                                            *
  10  * This program is distributed in the hope that it will be useful,            *
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of             *
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              *
  13  * GNU General Public License for more details.                               *
  14  *                                                                            *
  15  * You should have received a copy of the GNU General Public License          *
  16  * along with this program; if not, write to the Free Software Foundation     *
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.             *
  18  ******************************************************************************/
  19
  20 #include "base/tlsstream.hpp"
  21 #include "base/utility.hpp"
  22 #include "base/exception.hpp"
  23 #include "base/logger.hpp"
  24 #include "base/configuration.hpp"
  25 #include "base/convert.hpp"
  26 #include <iostream>
  27
  28 #ifndef _WIN32
  29 #       include <poll.h>
  30 #endif /* _WIN32 */
  31
  32 #define TLS_TIMEOUT_SECONDS 10
  33
  34 using namespace icinga;
  35
  36 int TlsStream::m_SSLIndex;
  37 bool TlsStream::m_SSLIndexInitialized = false;
  38
  39 /**
  40  * Constructor for the TlsStream class.
  41  *
  42  * @param role The role of the client.
  43  * @param sslContext The SSL context for the client.
  44  */
  45 TlsStream::TlsStream(const Socket::Ptr& socket, const String& hostname, ConnectionRole role, const std::shared_ptr<SSL_CTX>& sslContext)
  46         : SocketEvents(socket), m_Eof(false), m_HandshakeOK(false), m_VerifyOK(true), m_ErrorCode(0),
  47         m_ErrorOccurred(false),  m_Socket(socket), m_Role(role), m_SendQ(new FIFO()), m_RecvQ(new FIFO()),
  48         m_CurrentAction(TlsActionNone), m_Retry(false), m_Shutdown(false)
  49 {
  50         std::ostringstream msgbuf;
  51         char errbuf[120];
  52
  53         m_SSL = std::shared_ptr<SSL>(SSL_new(sslContext.get()), SSL_free);
  54
  55         if (!m_SSL) {
  56                 msgbuf << "SSL_new() failed with code " << ERR_peek_error() << ", \"" << ERR_error_string(ERR_peek_error(), errbuf) << "\"";
  57                 Log(LogCritical, "TlsStream", msgbuf.str());
  58
  59                 BOOST_THROW_EXCEPTION(openssl_error()
  60                         << boost::errinfo_api_function("SSL_new")
  61                         << errinfo_openssl_error(ERR_peek_error()));
  62         }
  63
  64         if (!m_SSLIndexInitialized) {
  65                 m_SSLIndex = SSL_get_ex_new_index(0, const_cast<char *>("TlsStream"), nullptr, nullptr, nullptr);
  66                 m_SSLIndexInitialized = true;
  67         }
  68
  69         SSL_set_ex_data(m_SSL.get(), m_SSLIndex, this);
  70
  71         SSL_set_verify(m_SSL.get(), SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, &TlsStream::ValidateCertificate);
  72
  73         socket->MakeNonBlocking();
  74
  75         SSL_set_fd(m_SSL.get(), socket->GetFD());
  76
  77         if (m_Role == RoleServer)
  78                 SSL_set_accept_state(m_SSL.get());
  79         else {
  80 #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
  81                 if (!hostname.IsEmpty())
  82                         SSL_set_tlsext_host_name(m_SSL.get(), hostname.CStr());
  83 #endif /* SSL_CTRL_SET_TLSEXT_HOSTNAME */
  84
  85                 SSL_set_connect_state(m_SSL.get());
  86         }
  87 }
  88
  89 TlsStream::~TlsStream()
  90 {
  91         CloseInternal(true);
  92 }
  93
  94 int TlsStream::ValidateCertificate(int preverify_ok, X509_STORE_CTX *ctx)
  95 {
  96         auto *ssl = static_cast<SSL *>(X509_STORE_CTX_get_ex_data(ctx, SSL_get_ex_data_X509_STORE_CTX_idx()));
  97         auto *stream = static_cast<TlsStream *>(SSL_get_ex_data(ssl, m_SSLIndex));
  98
  99         if (!preverify_ok) {
 100                 stream->m_VerifyOK = false;
 101
 102                 std::ostringstream msgbuf;
 103                 int err = X509_STORE_CTX_get_error(ctx);
 104                 msgbuf << "code " << err << ": " << X509_verify_cert_error_string(err);
 105                 stream->m_VerifyError = msgbuf.str();
 106         }
 107
 108         return 1;
 109 }
 110
 111 bool TlsStream::IsVerifyOK() const
 112 {
 113         return m_VerifyOK;
 114 }
 115
 116 String TlsStream::GetVerifyError() const
 117 {
 118         return m_VerifyError;
 119 }
 120
 121 /**
 122  * Retrieves the X509 certficate for this client.
 123  *
 124  * @returns The X509 certificate.
 125  */
 126 std::shared_ptr<X509> TlsStream::GetClientCertificate() const
 127 {
 128         boost::mutex::scoped_lock lock(m_Mutex);
 129         return std::shared_ptr<X509>(SSL_get_certificate(m_SSL.get()), &Utility::NullDeleter);
 130 }
 131
 132 /**
 133  * Retrieves the X509 certficate for the peer.
 134  *
 135  * @returns The X509 certificate.
 136  */
 137 std::shared_ptr<X509> TlsStream::GetPeerCertificate() const
 138 {
 139         boost::mutex::scoped_lock lock(m_Mutex);
 140         return std::shared_ptr<X509>(SSL_get_peer_certificate(m_SSL.get()), X509_free);
 141 }
 142
 143 void TlsStream::OnEvent(int revents)
 144 {
 145         int rc;
 146         size_t count;
 147
 148         boost::mutex::scoped_lock lock(m_Mutex);
 149
 150         if (!m_SSL)
 151                 return;
 152
 153         char buffer[64 * 1024];
 154
 155         if (m_CurrentAction == TlsActionNone) {
 156                 if (revents & (POLLIN | POLLERR | POLLHUP))
 157                         m_CurrentAction = TlsActionRead;
 158                 else if (m_SendQ->GetAvailableBytes() > 0 && (revents & POLLOUT))
 159                         m_CurrentAction = TlsActionWrite;
 160                 else {
 161                         ChangeEvents(POLLIN);
 162
 163                         return;
 164                 }
 165         }
 166
 167         bool success = false;
 168
 169         /* Clear error queue for this thread before using SSL_{read,write,do_handshake}.
 170          * Otherwise SSL_*_error() does not work reliably.
 171          */
 172         ERR_clear_error();
 173
 174         size_t readTotal = 0;
 175
 176         switch (m_CurrentAction) {
 177                 case TlsActionRead:
 178                         do {
 179                                 rc = SSL_read(m_SSL.get(), buffer, sizeof(buffer));
 180
 181                                 if (rc > 0) {
 182                                         m_RecvQ->Write(buffer, rc);
 183                                         success = true;
 184
 185                                         readTotal += rc;
 186                                 }
 187
 188 #ifdef I2_DEBUG /* I2_DEBUG */
 189                                 Log(LogDebug, "TlsStream")
 190                                         << "Read bytes: " << rc << " Total read bytes: " << readTotal;
 191 #endif /* I2_DEBUG */
 192                                 /* Limit read size. We cannot do this check inside the while loop
 193                                  * since below should solely check whether OpenSSL has more data
 194                                  * or not. */
 195                                 if (readTotal >= 64 * 1024) {
 196 #ifdef I2_DEBUG /* I2_DEBUG */
 197                                         Log(LogWarning, "TlsStream")
 198                                                 << "Maximum read bytes exceeded: " << readTotal;
 199 #endif /* I2_DEBUG */
 200                                         break;
 201                                 }
 202
 203                         /* Use OpenSSL's state machine here to determine whether we need
 204                          * to read more data. SSL_has_pending() is available with 1.1.0.
 205                          */
 206                         } while (SSL_pending(m_SSL.get()));
 207
 208                         if (success)
 209                                 m_CV.notify_all();
 210
 211                         break;
 212                 case TlsActionWrite:
 213                         count = m_SendQ->Peek(buffer, sizeof(buffer), true);
 214
 215                         rc = SSL_write(m_SSL.get(), buffer, count);
 216
 217                         if (rc > 0) {
 218                                 m_SendQ->Read(nullptr, rc, true);
 219                                 success = true;
 220                         }
 221
 222                         break;
 223                 case TlsActionHandshake:
 224                         rc = SSL_do_handshake(m_SSL.get());
 225
 226                         if (rc > 0) {
 227                                 success = true;
 228                                 m_HandshakeOK = true;
 229                                 m_CV.notify_all();
 230                         }
 231
 232                         break;
 233                 default:
 234                         VERIFY(!"Invalid TlsAction");
 235         }
 236
 237         if (rc <= 0) {
 238                 int err = SSL_get_error(m_SSL.get(), rc);
 239
 240                 switch (err) {
 241                         case SSL_ERROR_WANT_READ:
 242                                 m_Retry = true;
 243                                 ChangeEvents(POLLIN);
 244
 245                                 break;
 246                         case SSL_ERROR_WANT_WRITE:
 247                                 m_Retry = true;
 248                                 ChangeEvents(POLLOUT);
 249
 250                                 break;
 251                         case SSL_ERROR_ZERO_RETURN:
 252                                 lock.unlock();
 253
 254                                 Close();
 255
 256                                 return;
 257                         default:
 258                                 m_ErrorCode = ERR_peek_error();
 259                                 m_ErrorOccurred = true;
 260
 261                                 if (m_ErrorCode != 0) {
 262                                         Log(LogWarning, "TlsStream")
 263                                                 << "OpenSSL error: " << ERR_error_string(m_ErrorCode, nullptr);
 264                                 } else {
 265                                         Log(LogWarning, "TlsStream", "TLS stream was disconnected.");
 266                                 }
 267
 268                                 lock.unlock();
 269
 270                                 Close();
 271
 272                                 return;
 273                 }
 274         }
 275
 276         if (success) {
 277                 m_CurrentAction = TlsActionNone;
 278
 279                 if (!m_Eof) {
 280                         if (m_SendQ->GetAvailableBytes() > 0)
 281                                 ChangeEvents(POLLIN|POLLOUT);
 282                         else
 283                                 ChangeEvents(POLLIN);
 284                 }
 285
 286                 lock.unlock();
 287
 288                 while (m_RecvQ->IsDataAvailable() && IsHandlingEvents())
 289                         SignalDataAvailable();
 290         }
 291
 292         if (m_Shutdown && !m_SendQ->IsDataAvailable()) {
 293                 if (!success)
 294                         lock.unlock();
 295
 296                 Close();
 297         }
 298 }
 299
 300 void TlsStream::HandleError() const
 301 {
 302         if (m_ErrorOccurred) {
 303                 BOOST_THROW_EXCEPTION(openssl_error()
 304                         << boost::errinfo_api_function("TlsStream::OnEvent")
 305                         << errinfo_openssl_error(m_ErrorCode));
 306         }
 307 }
 308
 309 void TlsStream::Handshake()
 310 {
 311         boost::mutex::scoped_lock lock(m_Mutex);
 312
 313         m_CurrentAction = TlsActionHandshake;
 314         ChangeEvents(POLLOUT);
 315
 316         boost::system_time const timeout = boost::get_system_time() + boost::posix_time::milliseconds(long(Configuration::TlsHandshakeTimeout * 1000));
 317
 318         while (!m_HandshakeOK && !m_ErrorOccurred && !m_Eof && timeout > boost::get_system_time())
 319                 m_CV.timed_wait(lock, timeout);
 320
 321         if (timeout < boost::get_system_time())
 322                 BOOST_THROW_EXCEPTION(std::runtime_error("Timeout was reached (" + Convert::ToString(Configuration::TlsHandshakeTimeout) + ") during TLS handshake."));
 323
 324         if (m_Eof)
 325                 BOOST_THROW_EXCEPTION(std::runtime_error("Socket was closed during TLS handshake."));
 326
 327         HandleError();
 328 }
 329
 330 /**
 331  * Processes data for the stream.
 332  */
 333 size_t TlsStream::Peek(void *buffer, size_t count, bool allow_partial)
 334 {
 335         boost::mutex::scoped_lock lock(m_Mutex);
 336
 337         if (!allow_partial)
 338                 while (m_RecvQ->GetAvailableBytes() < count && !m_ErrorOccurred && !m_Eof)
 339                         m_CV.wait(lock);
 340
 341         HandleError();
 342
 343         return m_RecvQ->Peek(buffer, count, true);
 344 }
 345
 346 size_t TlsStream::Read(void *buffer, size_t count, bool allow_partial)
 347 {
 348         boost::mutex::scoped_lock lock(m_Mutex);
 349
 350         if (!allow_partial)
 351                 while (m_RecvQ->GetAvailableBytes() < count && !m_ErrorOccurred && !m_Eof)
 352                         m_CV.wait(lock);
 353
 354         HandleError();
 355
 356         return m_RecvQ->Read(buffer, count, true);
 357 }
 358
 359 void TlsStream::Write(const void *buffer, size_t count)
 360 {
 361         boost::mutex::scoped_lock lock(m_Mutex);
 362
 363         m_SendQ->Write(buffer, count);
 364
 365         ChangeEvents(POLLIN|POLLOUT);
 366 }
 367
 368 void TlsStream::Shutdown()
 369 {
 370         m_Shutdown = true;
 371         ChangeEvents(POLLOUT);
 372 }
 373
 374 /**
 375  * Closes the stream.
 376  */
 377 void TlsStream::Close()
 378 {
 379         CloseInternal(false);
 380 }
 381
 382 void TlsStream::CloseInternal(bool inDestructor)
 383 {
 384         if (m_Eof)
 385                 return;
 386
 387         m_Eof = true;
 388
 389         if (!inDestructor)
 390                 SignalDataAvailable();
 391
 392         SocketEvents::Unregister();
 393
 394         Stream::Close();
 395
 396         boost::mutex::scoped_lock lock(m_Mutex);
 397
 398         if (!m_SSL)
 399                 return;
 400
 401         /* https://www.openssl.org/docs/manmaster/man3/SSL_shutdown.html
 402          *
 403          * It is recommended to do a bidirectional shutdown by checking
 404          * the return value of SSL_shutdown() and call it again until
 405          * it returns 1 or a fatal error. A maximum of 2x pending + 2x data
 406          * is recommended.
 407          */
 408         int rc = 0;
 409
 410         for (int i = 0; i < 4; i++) {
 411                 if ((rc = SSL_shutdown(m_SSL.get())))
 412                         break;
 413         }
 414
 415         m_SSL.reset();
 416
 417         m_Socket->Close();
 418         m_Socket.reset();
 419
 420         m_CV.notify_all();
 421 }
 422
 423 bool TlsStream::IsEof() const
 424 {
 425         return m_Eof && m_RecvQ->GetAvailableBytes() < 1u;
 426 }
 427
 428 bool TlsStream::SupportsWaiting() const
 429 {
 430         return true;
 431 }
 432
 433 bool TlsStream::IsDataAvailable() const
 434 {
 435         boost::mutex::scoped_lock lock(m_Mutex);
 436
 437         return m_RecvQ->GetAvailableBytes() > 0;
 438 }
 439
 440 Socket::Ptr TlsStream::GetSocket() const
 441 {
 442         return m_Socket;
 443 }