blob: a064596881d47d2a774dac2e99b87c0f99046512 [file] [log] [blame]
/*
* Copyright 2008 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "rtc_base/openssladapter.h"
#if defined(WEBRTC_POSIX)
#include <unistd.h>
#endif
// Must be included first before openssl headers.
#include "rtc_base/win32.h" // NOLINT
#include <openssl/bio.h>
#include <openssl/crypto.h>
#include <openssl/err.h>
#include <openssl/opensslv.h>
#include <openssl/rand.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include "rtc_base/arraysize.h"
#include "rtc_base/checks.h"
#include "rtc_base/logging.h"
#include "rtc_base/numerics/safe_conversions.h"
#include "rtc_base/openssl.h"
#include "rtc_base/sslroots.h"
#include "rtc_base/stringencode.h"
#include "rtc_base/stringutils.h"
#include "rtc_base/thread.h"
#ifndef OPENSSL_IS_BORINGSSL
// TODO: Use a nicer abstraction for mutex.
#if defined(WEBRTC_WIN)
#define MUTEX_TYPE HANDLE
#define MUTEX_SETUP(x) (x) = CreateMutex(nullptr, FALSE, nullptr)
#define MUTEX_CLEANUP(x) CloseHandle(x)
#define MUTEX_LOCK(x) WaitForSingleObject((x), INFINITE)
#define MUTEX_UNLOCK(x) ReleaseMutex(x)
#define THREAD_ID GetCurrentThreadId()
#elif defined(WEBRTC_POSIX)
#define MUTEX_TYPE pthread_mutex_t
#define MUTEX_SETUP(x) pthread_mutex_init(&(x), nullptr)
#define MUTEX_CLEANUP(x) pthread_mutex_destroy(&(x))
#define MUTEX_LOCK(x) pthread_mutex_lock(&(x))
#define MUTEX_UNLOCK(x) pthread_mutex_unlock(&(x))
#define THREAD_ID pthread_self()
#else
#error You must define mutex operations appropriate for your platform!
#endif
struct CRYPTO_dynlock_value {
MUTEX_TYPE mutex;
};
#endif // #ifndef OPENSSL_IS_BORINGSSL
//////////////////////////////////////////////////////////////////////
// SocketBIO
//////////////////////////////////////////////////////////////////////
static int socket_write(BIO* h, const char* buf, int num);
static int socket_read(BIO* h, char* buf, int size);
static int socket_puts(BIO* h, const char* str);
static long socket_ctrl(BIO* h, int cmd, long arg1, void* arg2);
static int socket_new(BIO* h);
static int socket_free(BIO* data);
// TODO(davidben): This should be const once BoringSSL is assumed.
static BIO_METHOD methods_socket = {
BIO_TYPE_BIO, "socket", socket_write, socket_read, socket_puts, 0,
socket_ctrl, socket_new, socket_free, nullptr,
};
static BIO_METHOD* BIO_s_socket2() { return(&methods_socket); }
static BIO* BIO_new_socket(rtc::AsyncSocket* socket) {
BIO* ret = BIO_new(BIO_s_socket2());
if (ret == nullptr) {
return nullptr;
}
ret->ptr = socket;
return ret;
}
static int socket_new(BIO* b) {
b->shutdown = 0;
b->init = 1;
b->num = 0; // 1 means socket closed
b->ptr = 0;
return 1;
}
static int socket_free(BIO* b) {
if (b == nullptr)
return 0;
return 1;
}
static int socket_read(BIO* b, char* out, int outl) {
if (!out)
return -1;
rtc::AsyncSocket* socket = static_cast<rtc::AsyncSocket*>(b->ptr);
BIO_clear_retry_flags(b);
int result = socket->Recv(out, outl, nullptr);
if (result > 0) {
return result;
} else if (result == 0) {
b->num = 1;
} else if (socket->IsBlocking()) {
BIO_set_retry_read(b);
}
return -1;
}
static int socket_write(BIO* b, const char* in, int inl) {
if (!in)
return -1;
rtc::AsyncSocket* socket = static_cast<rtc::AsyncSocket*>(b->ptr);
BIO_clear_retry_flags(b);
int result = socket->Send(in, inl);
if (result > 0) {
return result;
} else if (socket->IsBlocking()) {
BIO_set_retry_write(b);
}
return -1;
}
static int socket_puts(BIO* b, const char* str) {
return socket_write(b, str, rtc::checked_cast<int>(strlen(str)));
}
static long socket_ctrl(BIO* b, int cmd, long num, void* ptr) {
switch (cmd) {
case BIO_CTRL_RESET:
return 0;
case BIO_CTRL_EOF:
return b->num;
case BIO_CTRL_WPENDING:
case BIO_CTRL_PENDING:
return 0;
case BIO_CTRL_FLUSH:
return 1;
default:
return 0;
}
}
static void LogSslError() {
// Walk down the error stack to find the SSL error.
uint32_t error_code;
const char* file;
int line;
do {
error_code = ERR_get_error_line(&file, &line);
if (ERR_GET_LIB(error_code) == ERR_LIB_SSL) {
RTC_LOG(LS_ERROR) << "ERR_LIB_SSL: " << error_code << ", " << file << ":"
<< line;
break;
}
} while (error_code != 0);
}
/////////////////////////////////////////////////////////////////////////////
// OpenSSLAdapter
/////////////////////////////////////////////////////////////////////////////
namespace rtc {
#ifndef OPENSSL_IS_BORINGSSL
// This array will store all of the mutexes available to OpenSSL.
static MUTEX_TYPE* mutex_buf = nullptr;
static void locking_function(int mode, int n, const char * file, int line) {
if (mode & CRYPTO_LOCK) {
MUTEX_LOCK(mutex_buf[n]);
} else {
MUTEX_UNLOCK(mutex_buf[n]);
}
}
static unsigned long id_function() { // NOLINT
// Use old-style C cast because THREAD_ID's type varies with the platform,
// in some cases requiring static_cast, and in others requiring
// reinterpret_cast.
return (unsigned long)THREAD_ID; // NOLINT
}
static CRYPTO_dynlock_value* dyn_create_function(const char* file, int line) {
CRYPTO_dynlock_value* value = new CRYPTO_dynlock_value;
if (!value)
return nullptr;
MUTEX_SETUP(value->mutex);
return value;
}
static void dyn_lock_function(int mode, CRYPTO_dynlock_value* l,
const char* file, int line) {
if (mode & CRYPTO_LOCK) {
MUTEX_LOCK(l->mutex);
} else {
MUTEX_UNLOCK(l->mutex);
}
}
static void dyn_destroy_function(CRYPTO_dynlock_value* l,
const char* file, int line) {
MUTEX_CLEANUP(l->mutex);
delete l;
}
#endif // #ifndef OPENSSL_IS_BORINGSSL
VerificationCallback OpenSSLAdapter::custom_verify_callback_ = nullptr;
bool OpenSSLAdapter::InitializeSSL(VerificationCallback callback) {
if (!InitializeSSLThread() || !SSL_library_init())
return false;
#if !defined(ADDRESS_SANITIZER) || !defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
// Loading the error strings crashes mac_asan. Omit this debugging aid there.
SSL_load_error_strings();
#endif
ERR_load_BIO_strings();
OpenSSL_add_all_algorithms();
RAND_poll();
custom_verify_callback_ = callback;
return true;
}
bool OpenSSLAdapter::InitializeSSLThread() {
// BoringSSL is doing the locking internally, so the callbacks are not used
// in this case (and are no-ops anyways).
#ifndef OPENSSL_IS_BORINGSSL
mutex_buf = new MUTEX_TYPE[CRYPTO_num_locks()];
if (!mutex_buf)
return false;
for (int i = 0; i < CRYPTO_num_locks(); ++i)
MUTEX_SETUP(mutex_buf[i]);
// we need to cast our id_function to return an unsigned long -- pthread_t is
// a pointer
CRYPTO_set_id_callback(id_function);
CRYPTO_set_locking_callback(locking_function);
CRYPTO_set_dynlock_create_callback(dyn_create_function);
CRYPTO_set_dynlock_lock_callback(dyn_lock_function);
CRYPTO_set_dynlock_destroy_callback(dyn_destroy_function);
#endif // #ifndef OPENSSL_IS_BORINGSSL
return true;
}
bool OpenSSLAdapter::CleanupSSL() {
#ifndef OPENSSL_IS_BORINGSSL
if (!mutex_buf)
return false;
CRYPTO_set_id_callback(nullptr);
CRYPTO_set_locking_callback(nullptr);
CRYPTO_set_dynlock_create_callback(nullptr);
CRYPTO_set_dynlock_lock_callback(nullptr);
CRYPTO_set_dynlock_destroy_callback(nullptr);
for (int i = 0; i < CRYPTO_num_locks(); ++i)
MUTEX_CLEANUP(mutex_buf[i]);
delete [] mutex_buf;
mutex_buf = nullptr;
#endif // #ifndef OPENSSL_IS_BORINGSSL
return true;
}
OpenSSLAdapter::OpenSSLAdapter(AsyncSocket* socket,
OpenSSLAdapterFactory* factory)
: SSLAdapter(socket),
factory_(factory),
state_(SSL_NONE),
role_(SSL_CLIENT),
ssl_read_needs_write_(false),
ssl_write_needs_read_(false),
restartable_(false),
ssl_(nullptr),
ssl_ctx_(nullptr),
ssl_mode_(SSL_MODE_TLS),
ignore_bad_cert_(false),
custom_verification_succeeded_(false) {
// If a factory is used, take a reference on the factory's SSL_CTX.
// Otherwise, we'll create our own later.
// Either way, we'll release our reference via SSL_CTX_free() in Cleanup().
if (factory_) {
ssl_ctx_ = factory_->ssl_ctx();
RTC_DCHECK(ssl_ctx_);
// Note: if using OpenSSL, requires version 1.1.0 or later.
SSL_CTX_up_ref(ssl_ctx_);
}
}
OpenSSLAdapter::~OpenSSLAdapter() {
Cleanup();
}
void OpenSSLAdapter::SetIgnoreBadCert(bool ignore) {
ignore_bad_cert_ = ignore;
}
void OpenSSLAdapter::SetAlpnProtocols(const std::vector<std::string>& protos) {
alpn_protocols_ = protos;
}
void OpenSSLAdapter::SetEllipticCurves(const std::vector<std::string>& curves) {
elliptic_curves_ = curves;
}
void OpenSSLAdapter::SetMode(SSLMode mode) {
RTC_DCHECK(!ssl_ctx_);
RTC_DCHECK(state_ == SSL_NONE);
ssl_mode_ = mode;
}
void OpenSSLAdapter::SetIdentity(SSLIdentity* identity) {
RTC_DCHECK(!identity_);
identity_.reset(static_cast<OpenSSLIdentity*>(identity));
}
void OpenSSLAdapter::SetRole(SSLRole role) {
role_ = role;
}
AsyncSocket* OpenSSLAdapter::Accept(SocketAddress* paddr) {
RTC_DCHECK(role_ == SSL_SERVER);
AsyncSocket* socket = SSLAdapter::Accept(paddr);
if (!socket) {
return nullptr;
}
SSLAdapter* adapter = SSLAdapter::Create(socket);
adapter->SetIdentity(identity_->GetReference());
adapter->SetRole(rtc::SSL_SERVER);
adapter->SetIgnoreBadCert(ignore_bad_cert_);
adapter->StartSSL("", false);
return adapter;
}
int OpenSSLAdapter::StartSSL(const char* hostname, bool restartable) {
if (state_ != SSL_NONE)
return -1;
ssl_host_name_ = hostname;
restartable_ = restartable;
if (socket_->GetState() != Socket::CS_CONNECTED) {
state_ = SSL_WAIT;
return 0;
}
state_ = SSL_CONNECTING;
if (int err = BeginSSL()) {
Error("BeginSSL", err, false);
return err;
}
return 0;
}
int OpenSSLAdapter::BeginSSL() {
RTC_LOG(LS_INFO) << "OpenSSLAdapter::BeginSSL: " << ssl_host_name_;
RTC_DCHECK(state_ == SSL_CONNECTING);
int err = 0;
BIO* bio = nullptr;
// First set up the context. We should either have a factory, with its own
// pre-existing context, or be running standalone, in which case we will
// need to create one, and specify |false| to disable session caching.
if (!factory_) {
RTC_DCHECK(!ssl_ctx_);
ssl_ctx_ = CreateContext(ssl_mode_, false);
}
if (!ssl_ctx_) {
err = -1;
goto ssl_error;
}
if (identity_ && !identity_->ConfigureIdentity(ssl_ctx_)) {
SSL_CTX_free(ssl_ctx_);
err = -1;
goto ssl_error;
}
bio = BIO_new_socket(socket_);
if (!bio) {
err = -1;
goto ssl_error;
}
ssl_ = SSL_new(ssl_ctx_);
if (!ssl_) {
err = -1;
goto ssl_error;
}
SSL_set_app_data(ssl_, this);
// SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER allows different buffers to be passed
// into SSL_write when a record could only be partially transmitted (and thus
// requires another call to SSL_write to finish transmission). This allows us
// to copy the data into our own buffer when this occurs, since the original
// buffer can't safely be accessed after control exits Send.
// TODO(deadbeef): Do we want SSL_MODE_ENABLE_PARTIAL_WRITE? It doesn't
// appear Send handles partial writes properly, though maybe we never notice
// since we never send more than 16KB at once..
SSL_set_mode(ssl_, SSL_MODE_ENABLE_PARTIAL_WRITE |
SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
// Enable SNI, if a hostname is supplied.
if (!ssl_host_name_.empty()) {
SSL_set_tlsext_host_name(ssl_, ssl_host_name_.c_str());
// Enable session caching, if configured and a hostname is supplied.
if (factory_) {
SSL_SESSION* cached = factory_->LookupSession(ssl_host_name_);
if (cached) {
if (SSL_set_session(ssl_, cached) == 0) {
RTC_LOG(LS_WARNING) << "Failed to apply SSL session from cache";
err = -1;
goto ssl_error;
}
RTC_LOG(LS_INFO) << "Attempting to resume SSL session to "
<< ssl_host_name_;
}
}
}
// Set a couple common TLS extensions; even though we don't use them yet.
SSL_enable_ocsp_stapling(ssl_);
SSL_enable_signed_cert_timestamps(ssl_);
if (!alpn_protocols_.empty()) {
std::string tls_alpn_string = TransformAlpnProtocols(alpn_protocols_);
if (!tls_alpn_string.empty()) {
SSL_set_alpn_protos(
ssl_, reinterpret_cast<const unsigned char*>(tls_alpn_string.data()),
tls_alpn_string.size());
}
}
if (!elliptic_curves_.empty()) {
SSL_set1_curves_list(ssl_, rtc::join(elliptic_curves_, ':').c_str());
}
// Now that the initial config is done, transfer ownership of |bio| to the
// SSL object. If ContinueSSL() fails, the bio will be freed in Cleanup().
SSL_set_bio(ssl_, bio, bio);
bio = nullptr;
// Do the connect.
err = ContinueSSL();
if (err != 0)
goto ssl_error;
return err;
ssl_error:
Cleanup();
if (bio)
BIO_free(bio);
return err;
}
int OpenSSLAdapter::ContinueSSL() {
RTC_DCHECK(state_ == SSL_CONNECTING);
// Clear the DTLS timer
Thread::Current()->Clear(this, MSG_TIMEOUT);
int code = (role_ == SSL_CLIENT) ? SSL_connect(ssl_) : SSL_accept(ssl_);
switch (SSL_get_error(ssl_, code)) {
case SSL_ERROR_NONE:
if (!SSLPostConnectionCheck(ssl_, ssl_host_name_.c_str())) {
RTC_LOG(LS_ERROR) << "TLS post connection check failed";
// make sure we close the socket
Cleanup();
// The connect failed so return -1 to shut down the socket
return -1;
}
state_ = SSL_CONNECTED;
AsyncSocketAdapter::OnConnectEvent(this);
#if 0 // TODO: worry about this
// Don't let ourselves go away during the callbacks
PRefPtr<OpenSSLAdapter> lock(this);
RTC_LOG(LS_INFO) << " -- onStreamReadable";
AsyncSocketAdapter::OnReadEvent(this);
RTC_LOG(LS_INFO) << " -- onStreamWriteable";
AsyncSocketAdapter::OnWriteEvent(this);
#endif
break;
case SSL_ERROR_WANT_READ:
RTC_LOG(LS_VERBOSE) << " -- error want read";
struct timeval timeout;
if (DTLSv1_get_timeout(ssl_, &timeout)) {
int delay = timeout.tv_sec * 1000 + timeout.tv_usec/1000;
Thread::Current()->PostDelayed(RTC_FROM_HERE, delay, this, MSG_TIMEOUT,
0);
}
break;
case SSL_ERROR_WANT_WRITE:
break;
case SSL_ERROR_ZERO_RETURN:
default:
RTC_LOG(LS_WARNING) << "ContinueSSL -- error " << code;
return (code != 0) ? code : -1;
}
return 0;
}
void OpenSSLAdapter::Error(const char* context, int err, bool signal) {
RTC_LOG(LS_WARNING) << "OpenSSLAdapter::Error(" << context << ", " << err
<< ")";
state_ = SSL_ERROR;
SetError(err);
if (signal)
AsyncSocketAdapter::OnCloseEvent(this, err);
}
void OpenSSLAdapter::Cleanup() {
RTC_LOG(LS_INFO) << "OpenSSLAdapter::Cleanup";
state_ = SSL_NONE;
ssl_read_needs_write_ = false;
ssl_write_needs_read_ = false;
custom_verification_succeeded_ = false;
pending_data_.Clear();
if (ssl_) {
SSL_free(ssl_);
ssl_ = nullptr;
}
if (ssl_ctx_) {
SSL_CTX_free(ssl_ctx_);
ssl_ctx_ = nullptr;
}
identity_.reset();
// Clear the DTLS timer
Thread::Current()->Clear(this, MSG_TIMEOUT);
}
int OpenSSLAdapter::DoSslWrite(const void* pv, size_t cb, int* error) {
// If we have pending data (that was previously only partially written by
// SSL_write), we shouldn't be attempting to write anything else.
RTC_DCHECK(pending_data_.empty() || pv == pending_data_.data());
RTC_DCHECK(error != nullptr);
ssl_write_needs_read_ = false;
int ret = SSL_write(ssl_, pv, checked_cast<int>(cb));
*error = SSL_get_error(ssl_, ret);
switch (*error) {
case SSL_ERROR_NONE:
// Success!
return ret;
case SSL_ERROR_WANT_READ:
RTC_LOG(LS_INFO) << " -- error want read";
ssl_write_needs_read_ = true;
SetError(EWOULDBLOCK);
break;
case SSL_ERROR_WANT_WRITE:
RTC_LOG(LS_INFO) << " -- error want write";
SetError(EWOULDBLOCK);
break;
case SSL_ERROR_ZERO_RETURN:
// RTC_LOG(LS_INFO) << " -- remote side closed";
SetError(EWOULDBLOCK);
// do we need to signal closure?
break;
case SSL_ERROR_SSL:
LogSslError();
Error("SSL_write", ret ? ret : -1, false);
break;
default:
RTC_LOG(LS_WARNING) << "Unknown error from SSL_write: " << *error;
Error("SSL_write", ret ? ret : -1, false);
break;
}
return SOCKET_ERROR;
}
//
// AsyncSocket Implementation
//
int OpenSSLAdapter::Send(const void* pv, size_t cb) {
// RTC_LOG(LS_INFO) << "OpenSSLAdapter::Send(" << cb << ")";
switch (state_) {
case SSL_NONE:
return AsyncSocketAdapter::Send(pv, cb);
case SSL_WAIT:
case SSL_CONNECTING:
SetError(ENOTCONN);
return SOCKET_ERROR;
case SSL_CONNECTED:
break;
case SSL_ERROR:
default:
return SOCKET_ERROR;
}
int ret;
int error;
if (!pending_data_.empty()) {
ret = DoSslWrite(pending_data_.data(), pending_data_.size(), &error);
if (ret != static_cast<int>(pending_data_.size())) {
// We couldn't finish sending the pending data, so we definitely can't
// send any more data. Return with an EWOULDBLOCK error.
SetError(EWOULDBLOCK);
return SOCKET_ERROR;
}
// We completed sending the data previously passed into SSL_write! Now
// we're allowed to send more data.
pending_data_.Clear();
}
// OpenSSL will return an error if we try to write zero bytes
if (cb == 0)
return 0;
ret = DoSslWrite(pv, cb, &error);
// If SSL_write fails with SSL_ERROR_WANT_READ or SSL_ERROR_WANT_WRITE, this
// means the underlying socket is blocked on reading or (more typically)
// writing. When this happens, OpenSSL requires that the next call to
// SSL_write uses the same arguments (though, with
// SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER, the actual buffer pointer may be
// different).
//
// However, after Send exits, we will have lost access to data the user of
// this class is trying to send, and there's no guarantee that the user of
// this class will call Send with the same arguements when it fails. So, we
// buffer the data ourselves. When we know the underlying socket is writable
// again from OnWriteEvent (or if Send is called again before that happens),
// we'll retry sending this buffered data.
if (error == SSL_ERROR_WANT_READ || error == SSL_ERROR_WANT_WRITE) {
// Shouldn't be able to get to this point if we already have pending data.
RTC_DCHECK(pending_data_.empty());
RTC_LOG(LS_WARNING)
<< "SSL_write couldn't write to the underlying socket; buffering data.";
pending_data_.SetData(static_cast<const uint8_t*>(pv), cb);
// Since we're taking responsibility for sending this data, return its full
// size. The user of this class can consider it sent.
return cb;
}
return ret;
}
int OpenSSLAdapter::SendTo(const void* pv,
size_t cb,
const SocketAddress& addr) {
if (socket_->GetState() == Socket::CS_CONNECTED &&
addr == socket_->GetRemoteAddress()) {
return Send(pv, cb);
}
SetError(ENOTCONN);
return SOCKET_ERROR;
}
int OpenSSLAdapter::Recv(void* pv, size_t cb, int64_t* timestamp) {
// RTC_LOG(LS_INFO) << "OpenSSLAdapter::Recv(" << cb << ")";
switch (state_) {
case SSL_NONE:
return AsyncSocketAdapter::Recv(pv, cb, timestamp);
case SSL_WAIT:
case SSL_CONNECTING:
SetError(ENOTCONN);
return SOCKET_ERROR;
case SSL_CONNECTED:
break;
case SSL_ERROR:
default:
return SOCKET_ERROR;
}
// Don't trust OpenSSL with zero byte reads
if (cb == 0)
return 0;
ssl_read_needs_write_ = false;
int code = SSL_read(ssl_, pv, checked_cast<int>(cb));
int error = SSL_get_error(ssl_, code);
switch (error) {
case SSL_ERROR_NONE:
// RTC_LOG(LS_INFO) << " -- success";
return code;
case SSL_ERROR_WANT_READ:
// RTC_LOG(LS_INFO) << " -- error want read";
SetError(EWOULDBLOCK);
break;
case SSL_ERROR_WANT_WRITE:
// RTC_LOG(LS_INFO) << " -- error want write";
ssl_read_needs_write_ = true;
SetError(EWOULDBLOCK);
break;
case SSL_ERROR_ZERO_RETURN:
// RTC_LOG(LS_INFO) << " -- remote side closed";
SetError(EWOULDBLOCK);
// do we need to signal closure?
break;
case SSL_ERROR_SSL:
LogSslError();
Error("SSL_read", (code ? code : -1), false);
break;
default:
RTC_LOG(LS_WARNING) << "Unknown error from SSL_read: " << error;
Error("SSL_read", (code ? code : -1), false);
break;
}
return SOCKET_ERROR;
}
int OpenSSLAdapter::RecvFrom(void* pv,
size_t cb,
SocketAddress* paddr,
int64_t* timestamp) {
if (socket_->GetState() == Socket::CS_CONNECTED) {
int ret = Recv(pv, cb, timestamp);
*paddr = GetRemoteAddress();
return ret;
}
SetError(ENOTCONN);
return SOCKET_ERROR;
}
int OpenSSLAdapter::Close() {
Cleanup();
state_ = restartable_ ? SSL_WAIT : SSL_NONE;
return AsyncSocketAdapter::Close();
}
Socket::ConnState OpenSSLAdapter::GetState() const {
//if (signal_close_)
// return CS_CONNECTED;
ConnState state = socket_->GetState();
if ((state == CS_CONNECTED)
&& ((state_ == SSL_WAIT) || (state_ == SSL_CONNECTING)))
state = CS_CONNECTING;
return state;
}
bool OpenSSLAdapter::IsResumedSession() {
return (ssl_ && SSL_session_reused(ssl_) == 1);
}
void OpenSSLAdapter::OnMessage(Message* msg) {
if (MSG_TIMEOUT == msg->message_id) {
RTC_LOG(LS_INFO) << "DTLS timeout expired";
DTLSv1_handle_timeout(ssl_);
ContinueSSL();
}
}
void OpenSSLAdapter::OnConnectEvent(AsyncSocket* socket) {
RTC_LOG(LS_INFO) << "OpenSSLAdapter::OnConnectEvent";
if (state_ != SSL_WAIT) {
RTC_DCHECK(state_ == SSL_NONE);
AsyncSocketAdapter::OnConnectEvent(socket);
return;
}
state_ = SSL_CONNECTING;
if (int err = BeginSSL()) {
AsyncSocketAdapter::OnCloseEvent(socket, err);
}
}
void OpenSSLAdapter::OnReadEvent(AsyncSocket* socket) {
// RTC_LOG(LS_INFO) << "OpenSSLAdapter::OnReadEvent";
if (state_ == SSL_NONE) {
AsyncSocketAdapter::OnReadEvent(socket);
return;
}
if (state_ == SSL_CONNECTING) {
if (int err = ContinueSSL()) {
Error("ContinueSSL", err);
}
return;
}
if (state_ != SSL_CONNECTED)
return;
// Don't let ourselves go away during the callbacks
//PRefPtr<OpenSSLAdapter> lock(this); // TODO: fix this
if (ssl_write_needs_read_) {
// RTC_LOG(LS_INFO) << " -- onStreamWriteable";
AsyncSocketAdapter::OnWriteEvent(socket);
}
// RTC_LOG(LS_INFO) << " -- onStreamReadable";
AsyncSocketAdapter::OnReadEvent(socket);
}
void OpenSSLAdapter::OnWriteEvent(AsyncSocket* socket) {
// RTC_LOG(LS_INFO) << "OpenSSLAdapter::OnWriteEvent";
if (state_ == SSL_NONE) {
AsyncSocketAdapter::OnWriteEvent(socket);
return;
}
if (state_ == SSL_CONNECTING) {
if (int err = ContinueSSL()) {
Error("ContinueSSL", err);
}
return;
}
if (state_ != SSL_CONNECTED)
return;
// Don't let ourselves go away during the callbacks
//PRefPtr<OpenSSLAdapter> lock(this); // TODO: fix this
if (ssl_read_needs_write_) {
// RTC_LOG(LS_INFO) << " -- onStreamReadable";
AsyncSocketAdapter::OnReadEvent(socket);
}
// If a previous SSL_write failed due to the underlying socket being blocked,
// this will attempt finishing the write operation.
if (!pending_data_.empty()) {
int error;
if (DoSslWrite(pending_data_.data(), pending_data_.size(), &error) ==
static_cast<int>(pending_data_.size())) {
pending_data_.Clear();
}
}
// RTC_LOG(LS_INFO) << " -- onStreamWriteable";
AsyncSocketAdapter::OnWriteEvent(socket);
}
void OpenSSLAdapter::OnCloseEvent(AsyncSocket* socket, int err) {
RTC_LOG(LS_INFO) << "OpenSSLAdapter::OnCloseEvent(" << err << ")";
AsyncSocketAdapter::OnCloseEvent(socket, err);
}
bool OpenSSLAdapter::VerifyServerName(SSL* ssl, const char* host,
bool ignore_bad_cert) {
if (!host)
return false;
// Checking the return from SSL_get_peer_certificate here is not strictly
// necessary. With our setup, it is not possible for it to return
// null. However, it is good form to check the return.
X509* certificate = SSL_get_peer_certificate(ssl);
if (!certificate)
return false;
// Logging certificates is extremely verbose. So it is disabled by default.
#ifdef LOG_CERTIFICATES
{
RTC_LOG(LS_INFO) << "Certificate from server:";
BIO* mem = BIO_new(BIO_s_mem());
X509_print_ex(mem, certificate, XN_FLAG_SEP_CPLUS_SPC, X509_FLAG_NO_HEADER);
BIO_write(mem, "\0", 1);
char* buffer;
BIO_get_mem_data(mem, &buffer);
RTC_LOG(LS_INFO) << buffer;
BIO_free(mem);
char* cipher_description =
SSL_CIPHER_description(SSL_get_current_cipher(ssl), nullptr, 128);
RTC_LOG(LS_INFO) << "Cipher: " << cipher_description;
OPENSSL_free(cipher_description);
}
#endif
bool ok = false;
GENERAL_NAMES* names = reinterpret_cast<GENERAL_NAMES*>(
X509_get_ext_d2i(certificate, NID_subject_alt_name, nullptr, nullptr));
if (names) {
for (size_t i = 0; i < sk_GENERAL_NAME_num(names); i++) {
const GENERAL_NAME* name = sk_GENERAL_NAME_value(names, i);
if (name->type != GEN_DNS)
continue;
std::string value(
reinterpret_cast<const char*>(ASN1_STRING_data(name->d.dNSName)),
ASN1_STRING_length(name->d.dNSName));
// string_match takes NUL-terminated strings, so check for embedded NULs.
if (value.find('\0') != std::string::npos)
continue;
if (string_match(host, value.c_str())) {
ok = true;
break;
}
}
GENERAL_NAMES_free(names);
}
char data[256];
X509_NAME* subject;
if (!ok && ((subject = X509_get_subject_name(certificate)) != nullptr) &&
(X509_NAME_get_text_by_NID(subject, NID_commonName, data, sizeof(data)) >
0)) {
data[sizeof(data)-1] = 0;
if (_stricmp(data, host) == 0)
ok = true;
}
X509_free(certificate);
// This should only ever be turned on for debugging and development.
if (!ok && ignore_bad_cert) {
RTC_LOG(LS_WARNING) << "TLS certificate check FAILED. "
<< "Allowing connection anyway.";
ok = true;
}
return ok;
}
bool OpenSSLAdapter::SSLPostConnectionCheck(SSL* ssl, const char* host) {
bool ok = VerifyServerName(ssl, host, ignore_bad_cert_);
if (ok) {
ok = (SSL_get_verify_result(ssl) == X509_V_OK ||
custom_verification_succeeded_);
}
if (!ok && ignore_bad_cert_) {
RTC_LOG(LS_INFO) << "Other TLS post connection checks failed.";
ok = true;
}
return ok;
}
#if !defined(NDEBUG)
// We only use this for tracing and so it is only needed in debug mode
void OpenSSLAdapter::SSLInfoCallback(const SSL* s, int where, int ret) {
const char* str = "undefined";
int w = where & ~SSL_ST_MASK;
if (w & SSL_ST_CONNECT) {
str = "SSL_connect";
} else if (w & SSL_ST_ACCEPT) {
str = "SSL_accept";
}
if (where & SSL_CB_LOOP) {
RTC_LOG(LS_INFO) << str << ":" << SSL_state_string_long(s);
} else if (where & SSL_CB_ALERT) {
str = (where & SSL_CB_READ) ? "read" : "write";
RTC_LOG(LS_INFO) << "SSL3 alert " << str << ":"
<< SSL_alert_type_string_long(ret) << ":"
<< SSL_alert_desc_string_long(ret);
} else if (where & SSL_CB_EXIT) {
if (ret == 0) {
RTC_LOG(LS_INFO) << str << ":failed in " << SSL_state_string_long(s);
} else if (ret < 0) {
RTC_LOG(LS_INFO) << str << ":error in " << SSL_state_string_long(s);
}
}
}
#endif
int OpenSSLAdapter::SSLVerifyCallback(int ok, X509_STORE_CTX* store) {
#if !defined(NDEBUG)
if (!ok) {
char data[256];
X509* cert = X509_STORE_CTX_get_current_cert(store);
int depth = X509_STORE_CTX_get_error_depth(store);
int err = X509_STORE_CTX_get_error(store);
RTC_LOG(LS_INFO) << "Error with certificate at depth: " << depth;
X509_NAME_oneline(X509_get_issuer_name(cert), data, sizeof(data));
RTC_LOG(LS_INFO) << " issuer = " << data;
X509_NAME_oneline(X509_get_subject_name(cert), data, sizeof(data));
RTC_LOG(LS_INFO) << " subject = " << data;
RTC_LOG(LS_INFO) << " err = " << err << ":"
<< X509_verify_cert_error_string(err);
}
#endif
// Get our stream pointer from the store
SSL* ssl = reinterpret_cast<SSL*>(
X509_STORE_CTX_get_ex_data(store,
SSL_get_ex_data_X509_STORE_CTX_idx()));
OpenSSLAdapter* stream =
reinterpret_cast<OpenSSLAdapter*>(SSL_get_app_data(ssl));
if (!ok && custom_verify_callback_) {
void* cert =
reinterpret_cast<void*>(X509_STORE_CTX_get_current_cert(store));
if (custom_verify_callback_(cert)) {
stream->custom_verification_succeeded_ = true;
RTC_LOG(LS_INFO) << "validated certificate using custom callback";
ok = true;
}
}
// Should only be used for debugging and development.
if (!ok && stream->ignore_bad_cert_) {
RTC_LOG(LS_WARNING) << "Ignoring cert error while verifying cert chain";
ok = 1;
}
return ok;
}
int OpenSSLAdapter::NewSSLSessionCallback(SSL* ssl, SSL_SESSION* session) {
OpenSSLAdapter* stream =
reinterpret_cast<OpenSSLAdapter*>(SSL_get_app_data(ssl));
RTC_DCHECK(stream->factory_);
RTC_LOG(LS_INFO) << "Caching SSL session for " << stream->ssl_host_name_;
stream->factory_->AddSession(stream->ssl_host_name_, session);
return 1; // We've taken ownership of the session; OpenSSL shouldn't free it.
}
bool OpenSSLAdapter::ConfigureTrustedRootCertificates(SSL_CTX* ctx) {
// Add the root cert that we care about to the SSL context
int count_of_added_certs = 0;
for (size_t i = 0; i < arraysize(kSSLCertCertificateList); i++) {
const unsigned char* cert_buffer = kSSLCertCertificateList[i];
size_t cert_buffer_len = kSSLCertCertificateSizeList[i];
X509* cert =
d2i_X509(nullptr, &cert_buffer, checked_cast<long>(cert_buffer_len));
if (cert) {
int return_value = X509_STORE_add_cert(SSL_CTX_get_cert_store(ctx), cert);
if (return_value == 0) {
RTC_LOG(LS_WARNING) << "Unable to add certificate.";
} else {
count_of_added_certs++;
}
X509_free(cert);
}
}
return count_of_added_certs > 0;
}
SSL_CTX* OpenSSLAdapter::CreateContext(SSLMode mode, bool enable_cache) {
// Use (D)TLS 1.2.
// Note: BoringSSL supports a range of versions by setting max/min version
// (Default V1.0 to V1.2). However (D)TLSv1_2_client_method functions used
// below in OpenSSL only support V1.2.
SSL_CTX* ctx = nullptr;
#ifdef OPENSSL_IS_BORINGSSL
ctx = SSL_CTX_new(mode == SSL_MODE_DTLS ? DTLS_method() : TLS_method());
#else
ctx = SSL_CTX_new(mode == SSL_MODE_DTLS ? DTLSv1_2_client_method()
: TLSv1_2_client_method());
#endif // OPENSSL_IS_BORINGSSL
if (ctx == nullptr) {
unsigned long error = ERR_get_error(); // NOLINT: type used by OpenSSL.
RTC_LOG(LS_WARNING) << "SSL_CTX creation failed: " << '"'
<< ERR_reason_error_string(error) << "\" "
<< "(error=" << error << ')';
return nullptr;
}
if (!ConfigureTrustedRootCertificates(ctx)) {
SSL_CTX_free(ctx);
return nullptr;
}
#if !defined(NDEBUG)
SSL_CTX_set_info_callback(ctx, SSLInfoCallback);
#endif
SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, SSLVerifyCallback);
SSL_CTX_set_verify_depth(ctx, 4);
// Use defaults, but disable HMAC-SHA256 and HMAC-SHA384 ciphers
// (note that SHA256 and SHA384 only select legacy CBC ciphers).
// Additionally disable HMAC-SHA1 ciphers in ECDSA. These are the remaining
// CBC-mode ECDSA ciphers.
SSL_CTX_set_cipher_list(
ctx, "ALL:!SHA256:!SHA384:!aPSK:!ECDSA+SHA1:!ADH:!LOW:!EXP:!MD5");
if (mode == SSL_MODE_DTLS) {
SSL_CTX_set_read_ahead(ctx, 1);
}
if (enable_cache) {
SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_CLIENT);
SSL_CTX_sess_set_new_cb(ctx, &OpenSSLAdapter::NewSSLSessionCallback);
}
return ctx;
}
std::string TransformAlpnProtocols(
const std::vector<std::string>& alpn_protocols) {
// Transforms the alpn_protocols list to the format expected by
// Open/BoringSSL. This requires joining the protocols into a single string
// and prepending a character with the size of the protocol string before
// each protocol.
std::string transformed_alpn;
for (const std::string& proto : alpn_protocols) {
if (proto.size() == 0 || proto.size() > 0xFF) {
RTC_LOG(LS_ERROR) << "OpenSSLAdapter::Error("
<< "TransformAlpnProtocols received proto with size "
<< proto.size() << ")";
return "";
}
transformed_alpn += static_cast<char>(proto.size());
transformed_alpn += proto;
RTC_LOG(LS_VERBOSE) << "TransformAlpnProtocols: Adding proto: " << proto;
}
return transformed_alpn;
}
//////////////////////////////////////////////////////////////////////
// OpenSSLAdapterFactory
//////////////////////////////////////////////////////////////////////
OpenSSLAdapterFactory::OpenSSLAdapterFactory()
: ssl_mode_(SSL_MODE_TLS), ssl_ctx_(nullptr) {}
OpenSSLAdapterFactory::~OpenSSLAdapterFactory() {
for (auto it : sessions_) {
SSL_SESSION_free(it.second);
}
SSL_CTX_free(ssl_ctx_);
}
void OpenSSLAdapterFactory::SetMode(SSLMode mode) {
RTC_DCHECK(!ssl_ctx_);
ssl_mode_ = mode;
}
OpenSSLAdapter* OpenSSLAdapterFactory::CreateAdapter(AsyncSocket* socket) {
if (!ssl_ctx_) {
bool enable_cache = true;
ssl_ctx_ = OpenSSLAdapter::CreateContext(ssl_mode_, enable_cache);
if (!ssl_ctx_) {
return nullptr;
}
}
return new OpenSSLAdapter(socket, this);
}
SSL_SESSION* OpenSSLAdapterFactory::LookupSession(const std::string& hostname) {
auto it = sessions_.find(hostname);
return (it != sessions_.end()) ? it->second : nullptr;
}
void OpenSSLAdapterFactory::AddSession(const std::string& hostname,
SSL_SESSION* new_session) {
SSL_SESSION* old_session = LookupSession(hostname);
SSL_SESSION_free(old_session);
sessions_[hostname] = new_session;
}
} // namespace rtc