proto.cpp

//    OpenVPN -- An application to securely tunnel IP networks
//               over a single port, with support for SSL/TLS-based
//               session authentication and key exchange,
//               packet encryption, packet authentication, and
//               packet compression.
//
//    Copyright (C) 2012-2017 OpenVPN Technologies, Inc.
//
//    This program is free software: you can redistribute it and/or modify
//    it under the terms of the GNU General Public License Version 3
//    as published by the Free Software Foundation.
//
//    This program is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU General Public License for more details.
//
//    You should have received a copy of the GNU General Public License
//    along with this program in the COPYING file.
//    If not, see <http://www.gnu.org/licenses/>.

// Unit test for OpenVPN Protocol implementation (class ProtoContext)

#include <iostream>
#include <string>
#include <sstream>
#include <deque>
#include <algorithm>
#include <cstring>
#include <limits>
#include <thread>

#include <openvpn/common/platform.hpp>

#ifdef OPENVPN_PLATFORM_WIN
#include "protowin.h"
#endif

#define OPENVPN_DEBUG
#define OPENVPN_ENABLE_ASSERT
#define USE_TLS_AUTH

// Data limits for Blowfish and other 64-bit block-size ciphers
#ifndef BF
#define BF 0
#endif
#define OPENVPN_BS64_DATA_LIMIT 50000
#if BF == 1
#define PROTO_CIPHER "BF-CBC"
#define TLS_VER_MIN TLSVersion::UNDEF
#define HANDSHAKE_WINDOW 60
#define BECOME_PRIMARY_CLIENT 5
#define BECOME_PRIMARY_SERVER 5
#define TLS_TIMEOUT_CLIENT 1000
#define TLS_TIMEOUT_SERVER 1000
#define FEEDBACK 0
#elif BF == 2
#define PROTO_CIPHER "BF-CBC"
#define TLS_VER_MIN TLSVersion::UNDEF
#define HANDSHAKE_WINDOW 10
#define BECOME_PRIMARY_CLIENT 10
#define BECOME_PRIMARY_SERVER 10
#define TLS_TIMEOUT_CLIENT 2000
#define TLS_TIMEOUT_SERVER 1000
#define FEEDBACK 0
#elif BF == 3
#define PROTO_CIPHER "BF-CBC"
#define TLS_VER_MIN TLSVersion::UNDEF
#define HANDSHAKE_WINDOW 60
#define BECOME_PRIMARY_CLIENT 60
#define BECOME_PRIMARY_SERVER 10
#define TLS_TIMEOUT_CLIENT 2000
#define TLS_TIMEOUT_SERVER 1000
#define FEEDBACK 0
#elif BF != 0
#error unknown BF value
#endif

// TLS timeout
#ifndef TLS_TIMEOUT_CLIENT
#define TLS_TIMEOUT_CLIENT 2000
#endif
#ifndef TLS_TIMEOUT_SERVER
#define TLS_TIMEOUT_SERVER 2000
#endif

// NoisyWire
#ifndef NOERR
#define SIMULATE_OOO
#define SIMULATE_DROPPED
#define SIMULATE_CORRUPTED
#endif

// how many virtual seconds between SSL renegotiations
#ifndef RENEG
#define RENEG 900
#endif

// feedback
#ifndef FEEDBACK
#define FEEDBACK 1
#else
#define FEEDBACK 0
#endif

// number of threads to use for test
#ifndef N_THREADS
#define N_THREADS 1
#endif

// number of iterations
#ifndef ITER
#define ITER 1000000
#endif

// number of high-level session iterations
#ifndef SITER
#define SITER 1
#endif

// abort if we reach this limit
//#define DROUGHT_LIMIT 100000

#if !defined(VERBOSE) && !defined(QUIET) && ITER <= 10000
#define VERBOSE
#endif

#ifdef VERBOSE
#define OPENVPN_DEBUG_PROTO 2
#define OPENVPN_LOG_SSL(x) OPENVPN_LOG(x)
#else
#define OPENVPN_LOG_SSL(x) // disable
#endif

#define STRINGIZE1(x) #x
#define STRINGIZE(x) STRINGIZE1(x)

// setup cipher
#ifndef PROTO_CIPHER
#ifdef PROTOv2
#define PROTO_CIPHER "AES-256-GCM"
#define TLS_VER_MIN TLSVersion::V1_2
#else
#define PROTO_CIPHER "AES-128-CBC"
#define TLS_VER_MIN TLSVersion::UNDEF
#endif
#endif

// setup digest
#ifndef PROTO_DIGEST
#define PROTO_DIGEST "SHA1"
#endif

// setup compressor
#ifdef PROTOv2
#ifdef HAVE_LZ4
#define COMP_METH CompressContext::LZ4v2
#else
#define COMP_METH CompressContext::COMP_STUBv2
#endif
#else
#define COMP_METH CompressContext::LZO_STUB
#endif

#include <openvpn/log/logsimple.hpp>

#include <openvpn/common/exception.hpp>
#include <openvpn/common/file.hpp>
#include <openvpn/common/count.hpp>
#include <openvpn/time/time.hpp>
#include <openvpn/random/mtrandapi.hpp>
#include <openvpn/frame/frame.hpp>
#include <openvpn/ssl/proto.hpp>
#include <openvpn/init/initprocess.hpp>

#include <openvpn/crypto/cryptodcsel.hpp>

#if defined(USE_MBEDTLS_APPLE_HYBRID)
#define USE_MBEDTLS
#endif

#if !(defined(USE_OPENSSL) || defined(USE_MBEDTLS) || defined(USE_APPLE_SSL))
#error Must define one or more of USE_OPENSSL, USE_MBEDTLS, USE_APPLE_SSL.
#endif

#if defined(USE_OPENSSL) && (defined(USE_MBEDTLS) || defined(USE_APPLE_SSL))
#undef USE_OPENSSL
#define USE_OPENSSL_SERVER
#elif !defined(USE_OPENSSL) && defined(USE_MBEDTLS)
#define USE_MBEDTLS_SERVER
#elif defined(USE_OPENSSL) && !defined(USE_MBEDTLS)
#define USE_OPENSSL_SERVER
#else
#error no server setup
#endif

#if defined(USE_OPENSSL) || defined(USE_OPENSSL_SERVER)
#include <openvpn/openssl/util/init.hpp>

#include <openvpn/openssl/crypto/api.hpp>
#include <openvpn/openssl/ssl/sslctx.hpp>
#include <openvpn/openssl/util/rand.hpp>

#endif

#if defined(USE_APPLE_SSL) || defined(USE_MBEDTLS_APPLE_HYBRID)
#include <openvpn/applecrypto/crypto/api.hpp>
#include <openvpn/applecrypto/ssl/sslctx.hpp>
#include <openvpn/applecrypto/util/rand.hpp>
#endif

#if defined(USE_MBEDTLS) || defined(USE_MBEDTLS_SERVER)
#include <openvpn/mbedtls/crypto/api.hpp>
#include <openvpn/mbedtls/ssl/sslctx.hpp>
#include <openvpn/mbedtls/util/rand.hpp>
#include <mbedtls/debug.h>
#endif

#include <openvpn/crypto/selftest.hpp>

using namespace openvpn;

// server Crypto/SSL/Rand implementation
#if defined(USE_MBEDTLS_SERVER)
typedef MbedTLSCryptoAPI ServerCryptoAPI;
typedef MbedTLSContext ServerSSLAPI;
typedef MbedTLSRandom ServerRandomAPI;
#elif defined(USE_OPENSSL_SERVER)
typedef OpenSSLCryptoAPI ServerCryptoAPI;
typedef OpenSSLContext ServerSSLAPI;
typedef OpenSSLRandom ServerRandomAPI;
#else
#error No server SSL implementation defined
#endif

// client SSL implementation can be OpenSSL, Apple SSL, or MbedTLS
#if defined(USE_MBEDTLS)
#if defined(USE_MBEDTLS_APPLE_HYBRID)
typedef AppleCryptoAPI ClientCryptoAPI;
#else
typedef MbedTLSCryptoAPI ClientCryptoAPI;
#endif
typedef MbedTLSContext ClientSSLAPI;
typedef MbedTLSRandom ClientRandomAPI;
#elif defined(USE_APPLE_SSL)
typedef AppleCryptoAPI ClientCryptoAPI;
typedef AppleSSLContext ClientSSLAPI;
typedef AppleRandom ClientRandomAPI;
#elif defined(USE_OPENSSL)
typedef OpenSSLCryptoAPI ClientCryptoAPI;
typedef OpenSSLContext ClientSSLAPI;
typedef OpenSSLRandom ClientRandomAPI;
#else
#error No client SSL implementation defined
#endif

const char message[] =
  "Message _->_ 0000000000 It was a bright cold day in April, and the clocks\n"
  "were striking thirteen. Winston Smith, his chin nuzzled\n"
  "into his breast in an effort to escape the vile wind,\n"
  "slipped quickly through the glass doors of Victory\n"
  "Mansions, though not quickly enough to prevent a\n"
  "swirl of gritty dust from entering along with him.\n"
#ifdef LARGE_MESSAGE
  "It was a bright cold day in April, and the clocks\n"
  "were striking thirteen. Winston Smith, his chin nuzzled\n"
  "into his breast in an effort to escape the vile wind,\n"
  "slipped quickly through the glass doors of Victory\n"
  "Mansions, though not quickly enough to prevent a\n"
  "swirl of gritty dust from entering along with him.\n"
  "It was a bright cold day in April, and the clocks\n"
  "were striking thirteen. Winston Smith, his chin nuzzled\n"
  "into his breast in an effort to escape the vile wind,\n"
  "slipped quickly through the glass doors of Victory\n"
  "Mansions, though not quickly enough to prevent a\n"
  "swirl of gritty dust from entering along with him.\n"
  "It was a bright cold day in April, and the clocks\n"
  "were striking thirteen. Winston Smith, his chin nuzzled\n"
  "into his breast in an effort to escape the vile wind,\n"
  "slipped quickly through the glass doors of Victory\n"
  "Mansions, though not quickly enough to prevent a\n"
  "swirl of gritty dust from entering along with him.\n"
  "It was a bright cold day in April, and the clocks\n"
  "were striking thirteen. Winston Smith, his chin nuzzled\n"
  "into his breast in an effort to escape the vile wind,\n"
  "slipped quickly through the glass doors of Victory\n"
  "Mansions, though not quickly enough to prevent a\n"
  "swirl of gritty dust from entering along with him.\n"
#endif
  ;

// A "Drought" measures the maximum period of time between
// any two successive events.  Used to measure worst-case
// packet loss.
class DroughtMeasure
{
public:
  OPENVPN_SIMPLE_EXCEPTION(drought_limit_exceeded);

  DroughtMeasure(const std::string& name_arg, TimePtr now_arg)
    : now(now_arg), name(name_arg)
  {
  }

  void event()
  {
    if (last_event.defined())
      {
	Time::Duration since_last = *now - last_event;
	if (since_last > drought)
	  {
	    drought = since_last;
#if defined(VERBOSE) || defined(DROUGHT_LIMIT)
	    {
	      const unsigned int r = drought.raw();
#if defined(VERBOSE)
	      std::cout << "*** Drought " << name << " has reached " << r << std::endl;
#endif
#ifdef DROUGHT_LIMIT
	      if (r > DROUGHT_LIMIT)
		throw drought_limit_exceeded();
#endif
	    }
#endif
	  }
      }
    last_event = *now;
  }

  Time::Duration operator()() const { return drought; }

private:
  TimePtr now;
  Time last_event;
  Time::Duration drought;
  std::string name;
};

// test the OpenVPN protocol implementation in ProtoContext
class TestProto : public ProtoContext
{
  typedef ProtoContext Base;

  using Base::now;
  using Base::mode;
  using Base::is_server;

public:
  using Base::flush;

  typedef Base::PacketType PacketType;

  OPENVPN_EXCEPTION(session_invalidated);

  TestProto(const Base::Config::Ptr& config,
	    const SessionStats::Ptr& stats)
    : Base(config, stats),
      control_drought("control", config->now),
      data_drought("data", config->now),
      frame(config->frame)
  {
    // zero progress value
    std::memset(progress_, 0, 11);
  }

  void reset()
  {
    net_out.clear();
    Base::reset();
  }

  void initial_app_send(const char *msg)
  {
    Base::start();
    const size_t msglen = std::strlen(msg) + 1;
    BufferAllocated app_buf((unsigned char *)msg, msglen, 0);
    copy_progress(app_buf);
    control_send(std::move(app_buf));
    flush(true);
  }

  void app_send_templ_init(const char *msg)
  {
    Base::start();
    const size_t msglen = std::strlen(msg) + 1;
    templ.reset(new BufferAllocated((unsigned char *)msg, msglen, 0));
    flush(true);
  }

  void app_send_templ()
  {
#if !FEEDBACK
    if (bool(iteration++ & 1) == is_server())
      {
	modmsg(templ);
	BufferAllocated app_buf(*templ);
	control_send(std::move(app_buf));
	flush(true);
	++n_control_send_;
      }
#endif
  }

  bool do_housekeeping()
  {
    if (now() >= Base::next_housekeeping())
      {
	Base::housekeeping();
	return true;
      }
    else
      return false;
  }

  void control_send(BufferPtr&& app_bp)
  {
    app_bytes_ += app_bp->size();
    Base::control_send(std::move(app_bp));
  }

  void control_send(BufferAllocated&& app_buf)
  {
    app_bytes_ += app_buf.size();
    Base::control_send(std::move(app_buf));
  }

  BufferPtr data_encrypt_string(const char *str)
  {
    BufferPtr bp = new BufferAllocated();
    frame->prepare(Frame::READ_LINK_UDP, *bp);
    bp->write((unsigned char *)str, std::strlen(str));
    data_encrypt(*bp);
    return bp;
  }

  void data_encrypt(BufferAllocated& in_out)
  {
    Base::data_encrypt(in_out);
  }

  void data_decrypt(const PacketType& type, BufferAllocated& in_out)
  {
    Base::data_decrypt(type, in_out);
    if (in_out.size())
      {
	data_bytes_ += in_out.size();
	data_drought.event();
      }
  }

  size_t net_bytes() const { return net_bytes_; }
  size_t app_bytes() const { return app_bytes_; }
  size_t data_bytes() const { return data_bytes_; }
  size_t n_control_recv() const { return n_control_recv_; }
  size_t n_control_send() const { return n_control_send_; }

  const char *progress() const { return progress_; }

  void finalize()
  {
    data_drought.event();
    control_drought.event();
  }

  void check_invalidated()
  {
    if (Base::invalidated())
      throw session_invalidated(Error::name(Base::invalidation_reason()));
  }

  std::deque<BufferPtr> net_out;

  DroughtMeasure control_drought;
  DroughtMeasure data_drought;

private:
  virtual void control_net_send(const Buffer& net_buf)
  {
    net_bytes_ += net_buf.size();
    net_out.push_back(BufferPtr(new BufferAllocated(net_buf, 0)));
  }

  virtual void control_recv(BufferPtr&& app_bp)
  {
    BufferPtr work;
    work.swap(app_bp);
    if (work->size() >= 23)
      std::memcpy(progress_, work->data()+13, 10);

#ifdef VERBOSE
    {
      const ssize_t trunc = 64;
      const std::string show((char *)work->data(), trunc);
      std::cout << now().raw() << " " << mode().str() << " " << show << std::endl;
    }
#endif
#if FEEDBACK
    modmsg(work);
    control_send(std::move(work));
#endif
    control_drought.event();
    ++n_control_recv_;
  }

  void copy_progress(Buffer& buf)
  {
    if (progress_[0]) // make sure progress was initialized
      std::memcpy(buf.data()+13, progress_, 10);    
  }

  void modmsg(BufferPtr& buf)
  {
    char *msg = (char *) buf->data();
    if (is_server())
      {
	msg[8] = 'S';
	msg[11] = 'C';
      }
    else
      {
	msg[8] = 'C';
	msg[11] = 'S';
      }

    // increment embedded number
    for (int i = 22; i >= 13; i--)
      {
	if (msg[i] != '9')
	  {
	    msg[i]++;
	    break;
	  }
	else
	  msg[i] = '0';
      }
  }

  Frame::Ptr frame;
  size_t app_bytes_ = 0;
  size_t net_bytes_ = 0;
  size_t data_bytes_ = 0;
  size_t n_control_send_ = 0;
  size_t n_control_recv_ = 0;
  BufferPtr templ;
  size_t iteration = 0;
  char progress_[11];
};

class TestProtoClient : public TestProto
{
  typedef TestProto Base;
public:
  TestProtoClient(const Base::Config::Ptr& config,
		  const SessionStats::Ptr& stats)
    : Base(config, stats)
  {
  }

private:
  virtual void client_auth(Buffer& buf)
  {
    const std::string username("foo");
    const std::string password("bar");
    Base::write_auth_string(username, buf);
    Base::write_auth_string(password, buf);
  }
};

class TestProtoServer : public TestProto
{
  typedef TestProto Base;
public:
  OPENVPN_SIMPLE_EXCEPTION(auth_failed);

  TestProtoServer(const Base::Config::Ptr& config,
		  const SessionStats::Ptr& stats)
    : Base(config, stats)
  {
  }

private:
  virtual void server_auth(const std::string& username,
			   const SafeString& password,
			   const std::string& peer_info,
			   const AuthCert::Ptr& auth_cert)
  {
#ifdef VERBOSE
    std::cout << "**** AUTHENTICATE " << username << '/' << password << " PEER INFO:" << std::endl;
    std::cout << peer_info;
#endif
    if (username != "foo" || password != "bar")
      throw auth_failed();
  }
};

// Simulate a noisy transmission channel where packets can be dropped,
// reordered, or corrupted.
class NoisyWire
{
public:
  NoisyWire(const std::string title_arg,
	    TimePtr now_arg,
	    RandomAPI& rand_arg,
	    const unsigned int reorder_prob_arg,
	    const unsigned int drop_prob_arg,
	    const unsigned int corrupt_prob_arg)
    : title(title_arg),
      now(now_arg),
      random(rand_arg),
      reorder_prob(reorder_prob_arg),
      drop_prob(drop_prob_arg),
      corrupt_prob(corrupt_prob_arg)
  {
  }

  template <typename T1, typename T2>
  void xfer(T1& a, T2& b)
  {
    // check for errors
    a.check_invalidated();
    b.check_invalidated();

    // need to retransmit?
    if (a.do_housekeeping())
      {
#ifdef VERBOSE
	std::cout << now->raw() << " " << title << " Housekeeping" << std::endl;
#endif
      }

    // queue a control channel packet
    a.app_send_templ();

    // queue a data channel packet
    if (a.data_channel_ready())
      {
	BufferPtr bp = a.data_encrypt_string("Waiting for godot A... Waiting for godot B... Waiting for godot C... Waiting for godot D... Waiting for godot E... Waiting for godot F... Waiting for godot G... Waiting for godot H... Waiting for godot I... Waiting for godot J...");
	wire.push_back(bp);
      }

    // transfer network packets from A -> wire
    while (!a.net_out.empty())
      {
	BufferPtr bp = a.net_out.front();
#ifdef VERBOSE
	std::cout << now->raw() << " " << title << " " << a.dump_packet(*bp) <<  std::endl;
#endif
	a.net_out.pop_front();
	wire.push_back(bp);
      }

    // transfer network packets from wire -> B
    while (true)
      {
	BufferPtr bp = recv();
	if (!bp)
	  break;
	typename T2::PacketType pt = b.packet_type(*bp);
	if (pt.is_control())
	  {
#ifdef VERBOSE
	    if (!b.control_net_validate(pt, *bp)) // not strictly necessary since control_net_recv will also validate
	      std::cout << now->raw() << " " << title << " CONTROL PACKET VALIDATION FAILED" << std::endl;
#endif
	    b.control_net_recv(pt, std::move(bp));
	  }
	else if (pt.is_data())
	  {
	    try {
	      b.data_decrypt(pt, *bp);
#ifdef VERBOSE
	      if (bp->size())
		{
		  const std::string show((char *)bp->data(), std::min(bp->size(), size_t(40)));
		  std::cout << now->raw() << " " << title << " DATA CHANNEL DECRYPT: " << show << std::endl;
		}
#endif
	    }
	    catch (const std::exception& e)
	      {
#ifdef VERBOSE
		std::cout << now->raw() << " " << title << " Exception on data channel decrypt: " << e.what() << std::endl;
#endif
	      }
	  }
	else
	  {
#ifdef VERBOSE
	    std::cout << now->raw() << " " << title << " KEY_STATE_ERROR" << std::endl;
#endif
	    b.stat().error(Error::KEY_STATE_ERROR);
	  }
      }
    b.flush(true);
  }

private:
  BufferPtr recv()
  {
#ifdef SIMULATE_OOO
    // simulate packets being received out of order
    if (wire.size() >= 2 && !rand(reorder_prob))
      {
	const size_t i = random.randrange(wire.size() - 1) + 1;
#ifdef VERBOSE
	std::cout << now->raw() << " " << title << " Simulating packet reordering " << i << " -> 0" <<  std::endl;
#endif
	std::swap(wire[0], wire[i]);
      }
#endif

    if (wire.size())
      {
	BufferPtr bp = wire.front();
	wire.pop_front();

#ifdef VERBOSE
	std::cout << now->raw() << " " << title << " Received packet, size=" << bp->size() << std::endl;
#endif

#ifdef SIMULATE_DROPPED
	// simulate dropped packet
	if (!rand(drop_prob))
	  {
#ifdef VERBOSE
	    std::cout << now->raw() << " " << title << " Simulating a dropped packet" << std::endl;
#endif
	    return BufferPtr();
	  }
#endif

#ifdef SIMULATE_CORRUPTED
	// simulate corrupted packet
	if (bp->size() && !rand(corrupt_prob))
	  {
#ifdef VERBOSE
	    std::cout << now->raw() << " " << title << " Simulating a corrupted packet" << std::endl;
#endif
	    const size_t pos = random.randrange(bp->size());
	    const unsigned char value = random.randrange(256);
	    (*bp)[pos] = value;
	  }
#endif
	return bp;
      }

    return BufferPtr();
  }

  unsigned int rand(const unsigned int prob)
  {
    if (prob)
      return random.randrange(prob);
    else
      return 1;
  }
  
  std::string title;
  TimePtr now;
  RandomAPI& random;
  unsigned int reorder_prob;
  unsigned int drop_prob;
  unsigned int corrupt_prob;
  std::deque<BufferPtr> wire;
};

class MySessionStats : public SessionStats
{
public:
  typedef RCPtr<MySessionStats> Ptr;

  MySessionStats()
  {
    std::memset(errors, 0, sizeof(errors));
  }

  virtual void error(const size_t err_type, const std::string* text=nullptr)
  {
    if (err_type < Error::N_ERRORS)
      ++errors[err_type];
  }

  count_t get_error_count(const Error::Type type) const
  {
    if (type < Error::N_ERRORS)
      return errors[type];
    else
      return 0;
  }

  void show_error_counts() const
  {
    for (size_t i = 0; i < Error::N_ERRORS; ++i)
      {
	count_t c = errors[i];
	if (c)
	  std::cerr << Error::name(i) << " : " << c << std::endl;
      }
  }

private:
  count_t errors[Error::N_ERRORS];
};

// execute the unit test in one thread
int test(const int thread_num)
{
  try {
    // frame
    Frame::Ptr frame(new Frame(Frame::Context(128, 256, 128, 0, 16, 0)));

    // RNG
    ClientRandomAPI::Ptr rng_cli(new ClientRandomAPI(false));
    ClientRandomAPI::Ptr prng_cli(new ClientRandomAPI(true));
    ServerRandomAPI::Ptr rng_serv(new ServerRandomAPI(false));
    ServerRandomAPI::Ptr prng_serv(new ServerRandomAPI(true));
    MTRand rng_noncrypto;

    // init simulated time
    Time time;
    const Time::Duration time_step = Time::Duration::binary_ms(100);

    // client config files
    const std::string ca_crt = read_text("ca.crt");
    const std::string client_crt = read_text("client.crt");
    const std::string client_key = read_text("client.key");
    const std::string server_crt = read_text("server.crt");
    const std::string server_key = read_text("server.key");
    const std::string dh_pem = read_text("dh.pem");
    const std::string tls_auth_key = read_text("tls-auth.key");

    // client config
    ClientSSLAPI::Config::Ptr cc(new ClientSSLAPI::Config());
    cc->set_mode(Mode(Mode::CLIENT));
    cc->set_frame(frame);
#ifdef FORCE_AES_CBC
    cc->set_force_aes_cbc_ciphersuites(true);
#endif
#ifdef USE_APPLE_SSL
    cc->load_identity("etest");
#else
    cc->load_ca(ca_crt, true);
    cc->load_cert(client_crt);
    cc->load_private_key(client_key);
#endif
    cc->set_tls_version_min(TLS_VER_MIN);
#ifdef VERBOSE
    cc->set_debug_level(1);
#endif
    cc->set_rng(rng_cli);

    // stats
    MySessionStats::Ptr cli_stats(new MySessionStats);
    MySessionStats::Ptr serv_stats(new MySessionStats);

    // client ProtoContext config
    typedef ProtoContext ClientProtoContext;
    ClientProtoContext::Config::Ptr cp(new ClientProtoContext::Config);
    cp->ssl_factory = cc->new_factory();
    cp->dc.set_factory(new CryptoDCSelect<ClientCryptoAPI>(frame, cli_stats, prng_cli));
    cp->tlsprf_factory.reset(new CryptoTLSPRFFactory<ClientCryptoAPI>());
    cp->frame = frame;
    cp->now = &time;
    cp->rng = rng_cli;
    cp->prng = prng_cli;
    cp->protocol = Protocol(Protocol::UDPv4);
    cp->layer = Layer(Layer::OSI_LAYER_3);
#ifdef PROTOv2
    cp->enable_op32 = true;
    cp->remote_peer_id = 100;
#endif
    cp->comp_ctx = CompressContext(COMP_METH, false);
    cp->dc.set_cipher(CryptoAlgs::lookup(PROTO_CIPHER));
    cp->dc.set_digest(CryptoAlgs::lookup(PROTO_DIGEST));
#ifdef USE_TLS_AUTH
    cp->tls_auth_factory.reset(new CryptoOvpnHMACFactory<ClientCryptoAPI>());
    cp->tls_auth_key.parse(tls_auth_key);
    cp->set_tls_auth_digest(CryptoAlgs::lookup(PROTO_DIGEST));
    cp->key_direction = 0;
#endif
    cp->reliable_window = 4;
    cp->max_ack_list = 4;
    cp->pid_mode = PacketIDReceive::UDP_MODE;
#if defined(HANDSHAKE_WINDOW)
    cp->handshake_window = Time::Duration::seconds(HANDSHAKE_WINDOW);
#elif SITER > 1
    cp->handshake_window = Time::Duration::seconds(30);
#else
    cp->handshake_window = Time::Duration::seconds(18); // will cause a small number of handshake failures
#endif
#ifdef BECOME_PRIMARY_CLIENT
    cp->become_primary = Time::Duration::seconds(BECOME_PRIMARY_CLIENT);
#else
    cp->become_primary = cp->handshake_window;
#endif
    cp->tls_timeout = Time::Duration::milliseconds(TLS_TIMEOUT_CLIENT);
#if defined(CLIENT_NO_RENEG)
    cp->renegotiate = Time::Duration::infinite();
#else
    cp->renegotiate = Time::Duration::seconds(RENEG);
#endif
    cp->expire = cp->renegotiate + cp->renegotiate;
    cp->keepalive_ping = Time::Duration::seconds(5);
    cp->keepalive_timeout = Time::Duration::seconds(60);

#ifdef VERBOSE
    std::cout << "CLIENT OPTIONS: " << cp->options_string() << std::endl;
    std::cout << "CLIENT PEER INFO:" << std::endl;
    std::cout << cp->peer_info_string();
#endif

    // server config
    ClientSSLAPI::Config::Ptr sc(new ClientSSLAPI::Config());
    sc->set_mode(Mode(Mode::SERVER));
    sc->set_frame(frame);
    sc->load_ca(ca_crt, true);
    sc->load_cert(server_crt);
    sc->load_private_key(server_key);
    sc->load_dh(dh_pem);
    sc->set_tls_version_min(TLS_VER_MIN);
    sc->set_rng(rng_serv);
#ifdef VERBOSE
    sc->set_debug_level(1);
#endif

    // server ProtoContext config
    typedef ProtoContext ServerProtoContext;
    ServerProtoContext::Config::Ptr sp(new ServerProtoContext::Config);
    sp->ssl_factory = sc->new_factory();
    sp->dc.set_factory(new CryptoDCSelect<ServerCryptoAPI>(frame, serv_stats, prng_serv));
    sp->tlsprf_factory.reset(new CryptoTLSPRFFactory<ServerCryptoAPI>());
    sp->frame = frame;
    sp->now = &time;
    sp->rng = rng_serv;
    sp->prng = prng_serv;
    sp->protocol = Protocol(Protocol::UDPv4);
    sp->layer = Layer(Layer::OSI_LAYER_3);
#ifdef PROTOv2
    sp->enable_op32 = true;
    sp->remote_peer_id = 101;
#endif
    sp->comp_ctx = CompressContext(COMP_METH, false);
    sp->dc.set_cipher(CryptoAlgs::lookup(PROTO_CIPHER));
    sp->dc.set_digest(CryptoAlgs::lookup(PROTO_DIGEST));
#ifdef USE_TLS_AUTH
    sp->tls_auth_factory.reset(new CryptoOvpnHMACFactory<ServerCryptoAPI>());
    sp->tls_auth_key.parse(tls_auth_key);
    sp->set_tls_auth_digest(CryptoAlgs::lookup(PROTO_DIGEST));
    sp->key_direction = 1;
#endif
    sp->reliable_window = 4;
    sp->max_ack_list = 4;
    sp->pid_mode = PacketIDReceive::UDP_MODE;
#if defined(HANDSHAKE_WINDOW)
    sp->handshake_window = Time::Duration::seconds(HANDSHAKE_WINDOW);
#elif SITER > 1
    sp->handshake_window = Time::Duration::seconds(30);
#else
    sp->handshake_window = Time::Duration::seconds(17) + Time::Duration::binary_ms(512);
#endif
#ifdef BECOME_PRIMARY_SERVER
    sp->become_primary = Time::Duration::seconds(BECOME_PRIMARY_SERVER);
#else
    sp->become_primary = sp->handshake_window;
#endif
    sp->tls_timeout = Time::Duration::milliseconds(TLS_TIMEOUT_SERVER);
#if defined(SERVER_NO_RENEG)
    sp->renegotiate = Time::Duration::infinite();
#else
    // NOTE: if we don't add sp->handshake_window, both client and server reneg-sec (RENEG)
    // will be equal and will therefore occasionally collide.  Such collisions can sometimes
    // produce this OpenSSL error:
    // OpenSSLContext::SSL::read_cleartext: BIO_read failed, cap=400 status=-1: error:140E0197:SSL routines:SSL_shutdown:shutdown while in init
    // The issue was introduced by this patch in OpenSSL:
    //   https://github.com/openssl/openssl/commit/64193c8218540499984cd63cda41f3cd491f3f59
    sp->renegotiate = Time::Duration::seconds(RENEG) + sp->handshake_window;
#endif
    sp->expire = sp->renegotiate + sp->renegotiate;
    sp->keepalive_ping = Time::Duration::seconds(5);
    sp->keepalive_timeout = Time::Duration::seconds(60);

#ifdef VERBOSE
    std::cout << "SERVER OPTIONS: " << sp->options_string() << std::endl;
    std::cout << "SERVER PEER INFO:" << std::endl;
    std::cout << sp->peer_info_string();
#endif

    TestProtoClient cli_proto(cp, cli_stats);
    TestProtoServer serv_proto(sp, serv_stats);

    for (int i = 0; i < SITER; ++i)
      {
#ifdef VERBOSE
	std::cout << "***** SITER " << i << std::endl;
#endif
	cli_proto.reset();
	serv_proto.reset();

	NoisyWire client_to_server("Client -> Server", &time, rng_noncrypto, 8, 16, 32); // last value: 32
	NoisyWire server_to_client("Server -> Client", &time, rng_noncrypto, 8, 16, 32); // last value: 32

	int j = -1;
	try {
#if FEEDBACK
	  // start feedback loop
	  cli_proto.initial_app_send(message);
	  serv_proto.start();
#else
	  cli_proto.app_send_templ_init(message);
	  serv_proto.app_send_templ_init(message);
#endif

	  // message loop
	  for (j = 0; j < ITER; ++j)
	    {
	      client_to_server.xfer(cli_proto, serv_proto);
	      server_to_client.xfer(serv_proto, cli_proto);
	      time += time_step;
	    }
	}
	catch (const std::exception& e)
	  {
	    std::cerr << "Exception[" << i << '/' << j << "]: " << e.what() << std::endl;
	    return 1;
	  }
      }

    cli_proto.finalize();
    serv_proto.finalize();

    const size_t ab = cli_proto.app_bytes() + serv_proto.app_bytes();
    const size_t nb = cli_proto.net_bytes() + serv_proto.net_bytes();
    const size_t db = cli_proto.data_bytes() + serv_proto.data_bytes();

    std::cerr << "*** app bytes=" << ab
	      << " net_bytes=" << nb
	      << " data_bytes=" << db
	      << " prog=" << cli_proto.progress() << '/' << serv_proto.progress()
#if !FEEDBACK
              << " CTRL=" << cli_proto.n_control_recv() << '/' << cli_proto.n_control_send() << '/' << serv_proto.n_control_recv() << '/' << serv_proto.n_control_send()
#endif
              << " D=" << cli_proto.control_drought().raw() << '/' << cli_proto.data_drought().raw() << '/' << serv_proto.control_drought().raw() << '/' << serv_proto.data_drought().raw()
              << " N=" << cli_proto.negotiations() << '/' << serv_proto.negotiations()
              << " SH=" << cli_proto.slowest_handshake().raw() << '/' << serv_proto.slowest_handshake().raw()
              << " HE=" << cli_stats->get_error_count(Error::HANDSHAKE_TIMEOUT) << '/' << serv_stats->get_error_count(Error::HANDSHAKE_TIMEOUT)
	      << std::endl;

#ifdef STATS
    std::cerr << "-------- CLIENT STATS --------" << std::endl;
    cli_stats->show_error_counts();
    std::cerr << "-------- SERVER STATS --------" << std::endl;
    serv_stats->show_error_counts();
#endif
#ifdef OPENVPN_MAX_DATALIMIT_BYTES
    std::cerr << "------------------------------" << std::endl;
    std::cerr << "MAX_DATALIMIT_BYTES=" << DataLimit::max_bytes() << std::endl;
#endif
  }
  catch (const std::exception& e)
    {
      std::cerr << "Exception: " << e.what() << std::endl;
      return 1;
    }
  return 0;
}

int main(int argc, char* argv[])
{
  // process-wide initialization
  InitProcess::init();

  // set global MbedTLS debug level
#if defined(USE_MBEDTLS)
  mbedtls_debug_set_threshold(1);
#endif

  if (argc >= 2 && !strcmp(argv[1], "test"))
    {
      const std::string out = SelfTest::crypto_self_test();
      OPENVPN_LOG(out);
      return 0;
    }

#if N_THREADS >= 2
  std::thread* threads[N_THREADS];
  int i;
  for (i = 0; i < N_THREADS; ++i)
    {
      threads[i] = new std::thread([i]() {
	  test(i);
	});
    }
  for (i = 0; i < N_THREADS; ++i)
    {
      threads[i]->join();
      delete threads[i];
    }
  return 0;
#else
  return test(1);
#endif
}