Attaching slightly modified sample which reproduces the problem (previous
one did not work sometimes).
Can be built as
g++ -o dtlstest main.cpp -std=c++11 -lssl -lcrypto -lpthread -g
On Wed, Dec 18, 2013 at 3:06 PM, Dmitry Sobinov via RT <[email protected]>wrote:
> Got some more info on this bug. It's a memory use after free.
>
> There's a problem with ssl_st::write_hash. It's cached
> in dtls1_buffer_message() function for each handshake message and got freed
> and replaced by new hash context when forming Change Cipher Spec message
> (in ssl_replace_hash(), see stack trace below). So, when we want to resend
> lost packet, old (already freed) hash context is used to create MACs for
> messages we want to resend, leading to crash on Win32 and undefined
> behavior on Linux.
>
> It's not a problem for initial handshake, because s->write_hash is zero and
> nothing gets destroyed when forming Change Cipher Spec.
>
> Any ideas how to workaround/fix this are appreciated.
>
> Here is the report from clang AddressSanitizer:
>
> ==32258==ERROR: AddressSanitizer: heap-use-after-free on address
> 0x60400000b890 at pc 0xa541d0 bp 0x7f9225188c50 sp 0x7f9225188c48
> READ of size 8 at 0x60400000b890 thread T1
> #0 0xa541cf in EVP_MD_CTX_md evp_lib.c:285
> #1 0x66e790 in dtls1_do_write d1_both.c:275
> #2 0x682231 in dtls1_retransmit_message d1_both.c:1290
> #3 0x67fe96 in dtls1_retransmit_buffered_messages d1_both.c:1145
> #4 0x64f934 in dtls1_handle_timeout d1_lib.c:451
> #5 0x65b6d4 in dtls1_read_bytes d1_pkt.c:832
> #6 0x67640a in dtls1_get_message_fragment d1_both.c:789
> #7 0x674459 in dtls1_get_message d1_both.c:437
> #8 0x79835b in ssl3_get_new_session_ticket s3_clnt.c:2040
> #9 0x63a5c1 in dtls1_connect d1_clnt.c:641
> #10 0x6bef29 in SSL_do_handshake ssl_lib.c:2564
> #11 0x4e11aa in _ZN17DtlsSrtpTransport18handshakeIterationEv
> test.cpp:348
> #12 0x5070b2 in _ZN17DtlsSrtpTransport19receiveTimerExpiredEv
> test.cpp:423
> #13 0x505128 in operator() test.cpp:392
> #14 0x504951 in
>
> _ZNSt3__18__invokeIRZN17DtlsSrtpTransport18handshakeIterationEvEUlvE_JEEEDTclclsr3std3__1E7forwardIT_Efp_Espclsr3std3__1E7forwardIT0_Efp0_EEEOS4_DpOS5_
> __functional_base:341
> #15 0x6069e9 in _ZNKSt3__18functionIFvvEEclEv functional:1436
> #16 0x603c64 in _ZN15AsyncDispatcher3runEv test.cpp:170
> #17 0x603928 in operator() test.cpp:88
> #18 0x6021c5 in
>
> _ZNSt3__17forwardIZN15AsyncDispatcherC1EvEUlvE_EEOT_RNS_16remove_referenceIS3_E4typeE
> type_traits:1341
> #19 0x460083 in _ZN6__asan10AsanThread11ThreadStartEm ??:?
> #20 0x7f922847e0a1 in start_thread pthread_create.c:?
> #21 0x7f922788b49c in __clone ??:?
> 0x60400000b890 is located 0 bytes inside of 48-byte region
> [0x60400000b890,0x60400000b8c0)
> freed by thread T1 here:
> #0 0x459a04 in __interceptor_free ??:?
> #1 0x897bdf in CRYPTO_free mem.c:397
> #2 0x9f97cf in EVP_MD_CTX_destroy digest.c:370
> #3 0x693983 in ssl_clear_hash_ctx ssl_lib.c:3244
> #4 0x6ca125 in ssl_replace_hash ssl_lib.c:3236
> #5 0x83e213 in tls1_change_cipher_state t1_enc.c:425
> #6 0x639971 in dtls1_connect d1_clnt.c:560
> #7 0x6bef29 in SSL_do_handshake ssl_lib.c:2564
> #8 0x4e11aa in _ZN17DtlsSrtpTransport18handshakeIterationEv
> test.cpp:348
> #9 0x4d7d98 in operator() test.cpp:219
> #10 0x4d52c1 in
>
> _ZNSt3__18__invokeIRZN17DtlsSrtpTransport18handleIncomingDataERKNS_6vectorIhNS_9allocatorIhEEEEEUlvE_JEEEDTclclsr3std3__1E7forwardIT_Efp_Espclsr3std3__1E7forwardIT0_Efp0_EEEOSA_DpOSB_
> __functional_base:341
> #11 0x6069e9 in _ZNKSt3__18functionIFvvEEclEv functional:1436
> #12 0x603c64 in _ZN15AsyncDispatcher3runEv test.cpp:170
> #13 0x603928 in operator() test.cpp:88
> #14 0x6021c5 in
>
> _ZNSt3__17forwardIZN15AsyncDispatcherC1EvEUlvE_EEOT_RNS_16remove_referenceIS3_E4typeE
> type_traits:1341
> #15 0x460083 in _ZN6__asan10AsanThread11ThreadStartEm ??:?
> previously allocated by thread T1 here:
> #0 0x459ae4 in __interceptor_malloc ??:?
> #1 0x89228c in default_malloc_ex mem.c:79
> #2 0x895a5c in CRYPTO_malloc mem.c:308
> #3 0x9f4515 in EVP_MD_CTX_create digest.c:131
> #4 0x6ca12a in ssl_replace_hash ssl_lib.c:3237
> #5 0x83e213 in tls1_change_cipher_state t1_enc.c:425
> #6 0x639971 in dtls1_connect d1_clnt.c:560
> #7 0x6bef29 in SSL_do_handshake ssl_lib.c:2564
> #8 0x4e11aa in _ZN17DtlsSrtpTransport18handshakeIterationEv
> test.cpp:348
> #9 0x4d7d98 in operator() test.cpp:219
> #10 0x4d52c1 in
>
> _ZNSt3__18__invokeIRZN17DtlsSrtpTransport18handleIncomingDataERKNS_6vectorIhNS_9allocatorIhEEEEEUlvE_JEEEDTclclsr3std3__1E7forwardIT_Efp_Espclsr3std3__1E7forwardIT0_Efp0_EEEOSA_DpOSB_
> __functional_base:341
> #11 0x6069e9 in _ZNKSt3__18functionIFvvEEclEv functional:1436
> #12 0x603c64 in _ZN15AsyncDispatcher3runEv test.cpp:170
> #13 0x603928 in operator() test.cpp:88
> #14 0x6021c5 in
>
> _ZNSt3__17forwardIZN15AsyncDispatcherC1EvEUlvE_EEOT_RNS_16remove_referenceIS3_E4typeE
> type_traits:1341
> #15 0x460083 in _ZN6__asan10AsanThread11ThreadStartEm ??:?
> Thread T1 created by T0 here:
> #0 0x455a50 in __interceptor_pthread_create ??:?
> #1 0x5ff729 in thread<<lambda at test.cpp:88:31>, , void> thread:355
> #2 0x5fd7b9 in thread<<lambda at test.cpp:88:31>, , void> thread:360
> #3 0x5fd068 in AsyncDispatcher test.cpp:88
> #4 0x4a3e3c in AsyncDispatcher test.cpp:89
> #5 0x4688f7 in main test.cpp:516
> #6 0x7f92277c7bc4 in __libc_start_main ??:?
>
>
>
> On Fri, Dec 13, 2013 at 5:55 PM, Dmitry Sobinov via RT <[email protected]
> >wrote:
>
> > Hello
> >
> > While testing renegotiations for DTLS-SRTP, found a crash on Windows.
> > OpenSSL version is 1.0.1e, also tested on the latest 1.0.1 snapshot.
> There
> > were 2 possible stack traces:
> >
> > AddLiveService.dll!EVP_MD_size(const env_md_st * md) Line 273 C
> > > AddLiveService.dll!dtls1_do_write(ssl_st * s, int type) Line 275 C
> > AddLiveService.dll!dtls1_retransmit_message(ssl_st * s, unsigned short
> > seq, unsigned long frag_off, int * found) Line 1293 C
> > AddLiveService.dll!dtls1_retransmit_buffered_messages(ssl_st * s) Line
> > 1145 C
> > AddLiveService.dll!dtls1_handle_timeout(ssl_st * s) Line 450 C
> > AddLiveService.dll!dtls1_read_bytes(ssl_st * s, int type, unsigned
> char *
> > buf, int len, int peek) Line 832 C
> > AddLiveService.dll!dtls1_get_message_fragment(ssl_st * s, int st1, int
> > stn, long max, int * ok) Line 789 C
> > AddLiveService.dll!dtls1_get_message(ssl_st * s, int st1, int stn, int
> > mt, long max, int * ok) Line 436 C
> > AddLiveService.dll!ssl3_get_new_session_ticket(ssl_st * s) Line 2046 C
> > AddLiveService.dll!dtls1_connect(ssl_st * s) Line 631 C
> > AddLiveService.dll!SSL_do_handshake(ssl_st * s) Line 2562 C
> >
> > and
> >
> > msvcr120d.dll!memcpy(unsigned char * dst, unsigned char * src, unsigned
> > long count) Line 188 Unknown
> > > dtls_test.exe!dtls1_get_message_fragment(ssl_st * s, int st1, int stn,
> > long max, int * ok) Line 789 C
> > dtls_test.exe!dtls1_get_message(ssl_st * s, int st1, int stn, int mt,
> > long max, int * ok) Line 436 C
> > dtls_test.exe!ssl3_get_new_session_ticket(ssl_st * s) Line 2046 C
> > dtls_test.exe!dtls1_connect(ssl_st * s) Line 631 C
> > dtls_test.exe!SSL_do_handshake(ssl_st * s) Line 2562 C
> >
> > Both are segfaults (access violations). On linux rehandshake doesn't
> finish
> > at all (failure after 1-2 minutes on timeout).
> >
> > You can find sample c++11 source file to reproduce this issue. In-memory
> > BIO pair is used, client and server in the same process. When no flights
> > are dropped, everything is fine.
> >
> > The sample can be compiled by MSVC 2013 on Windows and g++ 4.7+ (g++ -o
> > dtlstest main.cpp -std=c++11 -lssl -lcrypto -lpthread -g) or clang 3.2+.
> >
> >
> > ---
> > Dmitry Sobinov
> > AddLive.com
> > Live video and voice for your application
> >
> >
>
>
> ---
> Dmitry Sobinov
> AddLive.com
> Live video and voice for your application
>
> ______________________________________________________________________
> OpenSSL Project http://www.openssl.org
> Development Mailing List [email protected]
> Automated List Manager [email protected]
>
--
---
Dmitry Sobinov
AddLive.com
Live video and voice for your application
--
---
Dmitry Sobinov
AddLive.com
Live video and voice for your application
#include <iostream>
#include <string>
#include <mutex>
#include <thread>
#include <condition_variable>
#include <future>
#include <memory>
#include <vector>
#include <deque>
#include <chrono>
#include <algorithm>
#include <functional>
#include <stdint.h>
#include <assert.h>
#include <openssl/ssl.h>
#include <openssl/bio.h>
#include <openssl/err.h>
#include <openssl/x509.h>
// Can be built in MSVC 2013;
// with gcc:
// g++ -o dtlstest dtlstest.cpp -std=c++11 -lssl -lcrypto -lpthread -g -D_DEBUG
// clang with libc++:
// clang++ -o dtlstest dtlstest.cpp -std=c++11 -D_DEBUG -lssl -lcrypto -lpthread -stdlib=libc++ -lc++abi -g
std::chrono::steady_clock::time_point logStartingTime = std::chrono::steady_clock::now();
#define MLOG_D(x) std::cout << std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::steady_clock::now() - logStartingTime).count() << _label << x << std::endl;
#define LOG_E(x) std::cout << "[ERROR] " << x << std::endl;
#define MLOG_E(x) LOG_E(_label << x)
#ifdef X509_NAME
#undef X509_NAME // disable macro from wincrypt.h (included from dtls1.h/winsock.h)
#endif
struct DtlsIdentity
{
EVP_PKEY* key;
X509* certificate;
};
namespace
{
/**
* Helper functions (defined in the bottom of the file)
*/
unsigned long idFunction();
void opensslLockingFunc(int mode, int n,
const char* /*file*/, int /*line*/);
void opensslInit();
void opensslCleanup();
EVP_PKEY* generateRsaKeyPair();
X509* generateCertificate(EVP_PKEY* pkey, const char* commonName);
DtlsIdentity generateIdentity();
void logOpenSslErrors(const std::string& prefix);
}
typedef std::function<void()> DispatcherTask;
/**
* Helper class to serialize all requests and data transmissions in
* queue in one separate thread (implementation of ActiveObject pattern).
*/
class AsyncDispatcher
{
struct TimedTask
{
DispatcherTask task;
std::chrono::steady_clock::time_point timeToFire;
int id;
};
public:
AsyncDispatcher()
{
_thread = std::thread([this](){ run(); });
}
int push(const DispatcherTask& task,
std::chrono::milliseconds delay = std::chrono::milliseconds(0))
{
std::unique_lock<std::mutex> lk(_queueMutex);
int id = _idCounter++;
_queue.push_back({ task, std::chrono::steady_clock::now() + delay, id });
std::stable_sort(_queue.begin(), _queue.end(),
[](const TimedTask& t1, const TimedTask& t2) -> bool { return t1.timeToFire < t2.timeToFire; });
lk.unlock();
_condVar.notify_one();
return id;
}
void stop()
{
std::unique_lock<std::mutex> lk(_queueMutex);
_active = false;
_queue.clear();
lk.unlock();
_condVar.notify_one();
_thread.join();
}
void cancelTimedTask(int id)
{
std::unique_lock<std::mutex> lk(_queueMutex);
_queue.erase(std::remove_if(_queue.begin(), _queue.end(),
[=](const TimedTask& elem){ return elem.id == id; }),
_queue.end());
lk.unlock();
_condVar.notify_one();
}
private:
bool waitAndPop(TimedTask& poppedValue)
{
std::unique_lock<std::mutex> lk(_queueMutex);
while (true)
{
if (_queue.empty())
{
// queue empty, new handlers are not allowed to add => exiting
if (!_active)
return false;
// wait for pushed element if no elements to process right away
_condVar.wait(lk);
continue;
}
auto nearestExpireTime = _queue.front().timeToFire;
if (nearestExpireTime >= std::chrono::steady_clock::now())
{
_condVar.wait_until(lk, nearestExpireTime);
continue;
}
// have some expired callbacks
break;
}
poppedValue = _queue.front();
_queue.pop_front();
return true;
}
void run()
{
bool hasPendingWork = true;
while (true)
{
TimedTask rec;
if (!waitAndPop(rec))
return;
rec.task();
} while (hasPendingWork);
}
std::thread _thread;
std::mutex _queueMutex;
std::condition_variable _condVar;
std::deque<TimedTask> _queue;
bool _active = true;
int _idCounter = 0;
};
enum DtlsRole
{
DTLS_CLIENT = 0,
DTLS_SERVER = 1
};
typedef std::function<void(const std::vector<uint8_t>&)> DtlsSendFunc;
typedef std::function<void(bool)> DtlsConnectResultHandler;
class DtlsSrtpTransport
{
public:
DtlsSrtpTransport(DtlsRole role, const std::string& label,
AsyncDispatcher& dispatcher) :
_role(role),
_label(label),
_dispatcher(dispatcher)
{
auto identity = generateIdentity();
_certificate = identity.certificate;
_pkey = identity.key;
MLOG_D("Starting DTLS");
_sslCtx = createSslContext();
assert(_sslCtx);
_ssl = ::SSL_new(_sslCtx);
assert(_ssl);
_inBio = BIO_new(BIO_s_mem());
_outBio = BIO_new(BIO_s_mem());
SSL_set_app_data(_ssl, this);
if (_role == DTLS_CLIENT)
::SSL_set_connect_state(_ssl);
else
::SSL_set_accept_state(_ssl);
::SSL_set_bio(_ssl, _inBio, _outBio); //< the SSL object owns the bio now
MLOG_D("DTLS context initialization finished");
}
~DtlsSrtpTransport()
{
stopInternal();
}
void handleIncomingData(const std::vector<uint8_t>& data)
{
// handle data in dispatcher thread
_dispatcher.push([this, data]()
{
MLOG_D("INCOMING DATA of size " << data.size());
(void)BIO_reset(_inBio);
(void)BIO_reset(_outBio);
::BIO_write(_inBio, &data[0], data.size());
handshakeIteration();
});
}
void setResultHandler(const DtlsConnectResultHandler& h)
{
_resultHandler = h;
}
void setSendFunction(const DtlsSendFunc& sendFunc)
{
_sendFunc = sendFunc;
}
void start()
{
// perform on dispatcher thread
_dispatcher.push([this](){ handshakeIteration(); });
}
void renegotiate()
{
// perform on dispatcher thread
_dispatcher.push([this]()
{
MLOG_D("<<<<Renegotiation requested>>>>");
assert(_handshakeCompleted);
assert(!_activeRenegotiation);
_activeRenegotiation = true;
(void)BIO_reset(_inBio);
(void)BIO_reset(_outBio);
//SSL_renegotiate_abbreviated(_ssl);
SSL_renegotiate(_ssl);
handshakeIteration();
});
}
private:
SSL_CTX* createSslContext()
{
SSL_CTX *ctx = (_role == DTLS_CLIENT) ?
::SSL_CTX_new(DTLSv1_client_method()) :
::SSL_CTX_new(DTLSv1_server_method());
assert(ctx);
assert(_certificate);
assert(_pkey);
::SSL_CTX_use_certificate(ctx, _certificate);
::SSL_CTX_use_PrivateKey(ctx, _pkey);
if (_role == DTLS_SERVER)
{
SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF);
}
::SSL_CTX_set_info_callback(ctx, &DtlsSrtpTransport::sslInfoCallback);
::SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
&DtlsSrtpTransport::sslVerifyCallback);
::SSL_CTX_set_verify_depth(ctx, 1);
::SSL_CTX_set_cipher_list(ctx, "ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH");
//::SSL_CTX_set_tlsext_use_srtp(ctx, "SRTP_AES128_CM_SHA1_32:SRTP_AES128_CM_SHA1_80");
SSL_CTX_set_read_ahead(ctx, 1);
// "bad decompression" error fix for some linuxes:
SSL_CTX_set_options(ctx, SSL_OP_NO_COMPRESSION);
// disable tickets for simplicity
SSL_CTX_set_options(ctx, SSL_OP_NO_TICKET);
return ctx;
}
void stopInternal()
{
if (_ssl)
{
::SSL_shutdown(_ssl);
::SSL_free(_ssl);
_ssl = NULL;
}
if (_sslCtx)
{
::SSL_CTX_free(_sslCtx);
_sslCtx = NULL;
}
}
void handshakeIteration()
{
// we don't actually read data, but need this for SSL_read:
uint8_t buf[4096];
// SSL_read after initial negotiation, SSL_do_handshake on client side
// when renegotiation requested
int res = (_handshakeCompleted && !_activeRenegotiation) ?
::SSL_read(_ssl, buf, sizeof(buf)) : ::SSL_do_handshake(_ssl);
// get pointer to data written by handshake
int outBioLen = 0;
uint8_t *outBioData;
outBioLen = BIO_get_mem_data(_outBio, &outBioData);
int err = ::SSL_get_error(_ssl, res);
struct timeval timeout;
// check if remote side requested renegotiation
if (!_activeRenegotiation && _handshakeCompleted && SSL_renegotiate_pending(_ssl) == 1)
{
MLOG_D("Remote renegotiation detected");
_activeRenegotiation = true;
}
// check if renegotiation finished
bool renegotiationFinished = _activeRenegotiation && SSL_renegotiate_pending(_ssl) == 0;
// handle handshake errors
switch (err)
{
case SSL_ERROR_NONE:
if (!_handshakeCompleted || renegotiationFinished)
{
_handshakeCompleted = true;
_activeRenegotiation = false;
reportSuccess();
_dispatcher.cancelTimedTask(_currentTimerId);
}
break;
case SSL_ERROR_WANT_READ:
if (renegotiationFinished)
{
_activeRenegotiation = false;
_dispatcher.cancelTimedTask(_currentTimerId);
reportSuccess();
}
else if (DTLSv1_get_timeout(_ssl, &timeout))
{
int delay = timeout.tv_sec * 1000 + timeout.tv_usec / 1000;
MLOG_D("WANT_READ: setting new timer for " << delay << "ms");
_currentTimerId = _dispatcher.push([this](){ receiveTimerExpired(); },
std::chrono::milliseconds(delay));
}
break;
default:
MLOG_E("Unexpected error while processing DTLS: " << err);
logOpenSslErrors("SSL reading");
_resultHandler(false);
_dispatcher.cancelTimedTask(_currentTimerId);
assert(false);
// don't write any data, just return:
return;
}
if (outBioLen)
{
MLOG_D("Sending handshake data for DTLS; size " << outBioLen);
std::vector<uint8_t> data(outBioData, outBioData + outBioLen);
_sendFunc(data);
}
}
void receiveTimerExpired()
{
MLOG_D("DTLS timer expired. Asking OpenSSL to repeat operations");
(void)BIO_reset(_inBio);
(void)BIO_reset(_outBio);
handshakeIteration();
}
void reportSuccess()
{
MLOG_D("Negotiation success");
_resultHandler(true);
}
static int sslVerifyCallback(int ok, X509_STORE_CTX* store)
{
// we don't verify certificate here for simplicity
return 1;
}
static void sslInfoCallback(const SSL* s, int where, int ret)
{
auto this_ = reinterpret_cast<DtlsSrtpTransport*>(SSL_get_app_data(s));
this_->sslInfoCallbackInternal(s, where, ret);
}
void sslInfoCallbackInternal(const SSL* s, int where, int ret)
{
std::string method = "undefined";
int w = where & ~SSL_ST_MASK;
if (w & SSL_ST_CONNECT)
{
method = "SSL_connect";
}
else if (w & SSL_ST_ACCEPT)
{
method = "SSL_accept";
}
if (where & SSL_CB_LOOP)
{
MLOG_D(method << ": " << SSL_state_string_long(s));
}
else if (where & SSL_CB_ALERT)
{
const char* direction = (where & SSL_CB_READ) ? "read" : "write";
MLOG_D("SSL3 alert " << direction
<< ":" << SSL_alert_type_string_long(ret)
<< ":" << SSL_alert_desc_string_long(ret));
}
else if (where & SSL_CB_EXIT)
{
if (ret == 0)
{
MLOG_D(method << " failed in " << SSL_state_string_long(s));
}
else if (ret < 0)
{
MLOG_D(method << " error in " << SSL_state_string_long(s));
}
}
}
SSL* _ssl = nullptr;
SSL_CTX* _sslCtx = nullptr;
BIO* _inBio = nullptr;
BIO* _outBio = nullptr;
X509* _certificate = nullptr;
EVP_PKEY* _pkey = nullptr;
bool _handshakeCompleted = false;
DtlsConnectResultHandler _resultHandler;
DtlsSendFunc _sendFunc;
DtlsRole _role;
std::string _label;
bool _activeRenegotiation = false;
int _currentTimerId = 0;
AsyncDispatcher& _dispatcher;
};
int main()
{
opensslInit();
AsyncDispatcher dispatcher;
DtlsSrtpTransport client(DTLS_CLIENT, " [C] ", dispatcher);
DtlsSrtpTransport server(DTLS_SERVER, " [S] ", dispatcher);
std::promise<bool> clientResultPromise;
std::promise<bool> serverResultPromise;
// on negotiation set promises so we can go on
client.setResultHandler([&](bool result){ clientResultPromise.set_value(result); });
server.setResultHandler([&](bool result){ serverResultPromise.set_value(result); });
int clientCounter = 0;
client.setSendFunction([&](const std::vector<uint8_t>& data)
{
clientCounter++;
if (clientCounter == 4) //< drop specific flight
return;
server.handleIncomingData(data);
});
server.setSendFunction([&](const std::vector<uint8_t>& data)
{
client.handleIncomingData(data);
});
client.start();
server.start();
// block until get results in promises
auto clientResult = clientResultPromise.get_future().get();
auto serverResult = serverResultPromise.get_future().get();
assert(clientResult);
assert(serverResult);
/// renegotiation
// reset promises
clientResultPromise = std::promise<bool>();
serverResultPromise = std::promise<bool>();
// ask for renegotiation
client.renegotiate();
// block until get results
clientResult = clientResultPromise.get_future().get();
serverResult = serverResultPromise.get_future().get();
assert(clientResult);
assert(serverResult);
dispatcher.stop();
opensslCleanup();
}
// Helper functions implementation
namespace
{
std::vector<std::shared_ptr<std::mutex>> opensslMutexes;
unsigned long idFunction()
{
return std::hash<std::thread::id>()(std::this_thread::get_id());
}
void opensslLockingFunc(int mode, int n,
const char* /*file*/, int /*line*/)
{
if (mode & CRYPTO_LOCK)
opensslMutexes[n]->lock();
else
opensslMutexes[n]->unlock();
}
void opensslInit()
{
::SSL_library_init();
::SSL_load_error_strings();
::OpenSSL_add_all_algorithms();
opensslMutexes.resize(::CRYPTO_num_locks());
for (auto& mutex : opensslMutexes)
mutex.reset(new std::mutex());
::CRYPTO_set_locking_callback(&opensslLockingFunc);
::CRYPTO_set_id_callback(&idFunction);
}
void opensslCleanup()
{
::CRYPTO_set_id_callback(0);
::CRYPTO_set_locking_callback(0);
::ERR_free_strings();
::ERR_remove_state(0);
::EVP_cleanup();
::CRYPTO_cleanup_all_ex_data();
}
const int gKeyLength = 1024;
// number of random bits for certificate serial number
const int gRandomBitsNum = 64;
// one year certificate validity
const int gCertificateLifetime = 60 * 60 * 24 * 365;
// to compensate for slightly incorrect system clocks
const int gCertificateValidationWindow = -60 * 60 * 24;
EVP_PKEY* generateRsaKeyPair()
{
EVP_PKEY* pkey = EVP_PKEY_new();
BIGNUM* exponent = BN_new();
RSA* rsa = RSA_new();
if (!pkey || !exponent || !rsa ||
!BN_set_word(exponent, 0x10001) ||
!RSA_generate_key_ex(rsa, gKeyLength, exponent, NULL) ||
!EVP_PKEY_assign_RSA(pkey, rsa))
{
EVP_PKEY_free(pkey);
BN_free(exponent);
RSA_free(rsa);
return NULL;
}
BN_free(exponent);
return pkey;
}
X509* generateCertificate(EVP_PKEY* pkey, const char* commonName)
{
X509* x509 = NULL;
BIGNUM* serialNumber = NULL;
X509_NAME* name = NULL;
if ((x509 = X509_new()) == NULL)
goto error;
if (!X509_set_pubkey(x509, pkey))
goto error;
ASN1_INTEGER* asn1SerialNumber;
if ((serialNumber = BN_new()) == NULL ||
!BN_pseudo_rand(serialNumber, gRandomBitsNum, 0, 0) ||
(asn1SerialNumber = X509_get_serialNumber(x509)) == NULL ||
!BN_to_ASN1_INTEGER(serialNumber, asn1SerialNumber))
goto error;
if (!X509_set_version(x509, 0L))
goto error;
if ((name = X509_NAME_new()) == NULL ||
!X509_NAME_add_entry_by_NID(name, NID_commonName, MBSTRING_UTF8,
(unsigned char*)commonName, -1, -1, 0) ||
!X509_set_subject_name(x509, name) ||
!X509_set_issuer_name(x509, name))
goto error;
if (!X509_gmtime_adj(X509_get_notBefore(x509), gCertificateValidationWindow) ||
!X509_gmtime_adj(X509_get_notAfter(x509), gCertificateLifetime))
goto error;
if (!X509_sign(x509, pkey, EVP_sha256()))
goto error;
BN_free(serialNumber);
X509_NAME_free(name);
return x509;
error:
BN_free(serialNumber);
X509_NAME_free(name);
X509_free(x509);
return NULL;
}
DtlsIdentity generateIdentity()
{
DtlsIdentity id;
id.key = generateRsaKeyPair();
id.certificate = generateCertificate(id.key, "TestCompany Inc");
return id;
}
void logOpenSslErrors(const std::string& prefix)
{
char errorBuf[200];
unsigned long err;
while ((err = ERR_get_error()) != 0)
{
ERR_error_string_n(err, errorBuf, sizeof(errorBuf));
LOG_E(prefix << ": " << errorBuf);
}
}
}
