500 lines
19 KiB
C++
500 lines
19 KiB
C++
/*
|
|
* Copyright 2013 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 "pc/webrtc_session_description_factory.h"
|
|
|
|
#include <stddef.h>
|
|
|
|
#include <memory>
|
|
#include <string>
|
|
#include <utility>
|
|
#include <vector>
|
|
|
|
#include "absl/algorithm/container.h"
|
|
#include "absl/types/optional.h"
|
|
#include "api/jsep.h"
|
|
#include "api/jsep_session_description.h"
|
|
#include "api/rtc_error.h"
|
|
#include "pc/session_description.h"
|
|
#include "rtc_base/checks.h"
|
|
#include "rtc_base/location.h"
|
|
#include "rtc_base/logging.h"
|
|
#include "rtc_base/ref_counted_object.h"
|
|
#include "rtc_base/ssl_identity.h"
|
|
#include "rtc_base/ssl_stream_adapter.h"
|
|
#include "rtc_base/string_encode.h"
|
|
|
|
using cricket::MediaSessionOptions;
|
|
using rtc::UniqueRandomIdGenerator;
|
|
|
|
namespace webrtc {
|
|
namespace {
|
|
static const char kFailedDueToIdentityFailed[] =
|
|
" failed because DTLS identity request failed";
|
|
static const char kFailedDueToSessionShutdown[] =
|
|
" failed because the session was shut down";
|
|
|
|
static const uint64_t kInitSessionVersion = 2;
|
|
|
|
// Check that each sender has a unique ID.
|
|
static bool ValidMediaSessionOptions(
|
|
const cricket::MediaSessionOptions& session_options) {
|
|
std::vector<cricket::SenderOptions> sorted_senders;
|
|
for (const cricket::MediaDescriptionOptions& media_description_options :
|
|
session_options.media_description_options) {
|
|
sorted_senders.insert(sorted_senders.end(),
|
|
media_description_options.sender_options.begin(),
|
|
media_description_options.sender_options.end());
|
|
}
|
|
absl::c_sort(sorted_senders, [](const cricket::SenderOptions& sender1,
|
|
const cricket::SenderOptions& sender2) {
|
|
return sender1.track_id < sender2.track_id;
|
|
});
|
|
return absl::c_adjacent_find(sorted_senders,
|
|
[](const cricket::SenderOptions& sender1,
|
|
const cricket::SenderOptions& sender2) {
|
|
return sender1.track_id == sender2.track_id;
|
|
}) == sorted_senders.end();
|
|
}
|
|
|
|
enum {
|
|
MSG_CREATE_SESSIONDESCRIPTION_SUCCESS,
|
|
MSG_CREATE_SESSIONDESCRIPTION_FAILED,
|
|
MSG_USE_CONSTRUCTOR_CERTIFICATE
|
|
};
|
|
|
|
struct CreateSessionDescriptionMsg : public rtc::MessageData {
|
|
explicit CreateSessionDescriptionMsg(
|
|
webrtc::CreateSessionDescriptionObserver* observer,
|
|
RTCError error_in)
|
|
: observer(observer), error(std::move(error_in)) {}
|
|
|
|
rtc::scoped_refptr<webrtc::CreateSessionDescriptionObserver> observer;
|
|
RTCError error;
|
|
std::unique_ptr<webrtc::SessionDescriptionInterface> description;
|
|
};
|
|
} // namespace
|
|
|
|
void WebRtcCertificateGeneratorCallback::OnFailure() {
|
|
SignalRequestFailed();
|
|
}
|
|
|
|
void WebRtcCertificateGeneratorCallback::OnSuccess(
|
|
const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) {
|
|
SignalCertificateReady(certificate);
|
|
}
|
|
|
|
// static
|
|
void WebRtcSessionDescriptionFactory::CopyCandidatesFromSessionDescription(
|
|
const SessionDescriptionInterface* source_desc,
|
|
const std::string& content_name,
|
|
SessionDescriptionInterface* dest_desc) {
|
|
if (!source_desc) {
|
|
return;
|
|
}
|
|
const cricket::ContentInfos& contents =
|
|
source_desc->description()->contents();
|
|
const cricket::ContentInfo* cinfo =
|
|
source_desc->description()->GetContentByName(content_name);
|
|
if (!cinfo) {
|
|
return;
|
|
}
|
|
size_t mediasection_index = static_cast<int>(cinfo - &contents[0]);
|
|
const IceCandidateCollection* source_candidates =
|
|
source_desc->candidates(mediasection_index);
|
|
const IceCandidateCollection* dest_candidates =
|
|
dest_desc->candidates(mediasection_index);
|
|
if (!source_candidates || !dest_candidates) {
|
|
return;
|
|
}
|
|
for (size_t n = 0; n < source_candidates->count(); ++n) {
|
|
const IceCandidateInterface* new_candidate = source_candidates->at(n);
|
|
if (!dest_candidates->HasCandidate(new_candidate)) {
|
|
dest_desc->AddCandidate(source_candidates->at(n));
|
|
}
|
|
}
|
|
}
|
|
|
|
WebRtcSessionDescriptionFactory::WebRtcSessionDescriptionFactory(
|
|
rtc::Thread* signaling_thread,
|
|
cricket::ChannelManager* channel_manager,
|
|
PeerConnectionInternal* pc,
|
|
const std::string& session_id,
|
|
std::unique_ptr<rtc::RTCCertificateGeneratorInterface> cert_generator,
|
|
const rtc::scoped_refptr<rtc::RTCCertificate>& certificate,
|
|
UniqueRandomIdGenerator* ssrc_generator)
|
|
: signaling_thread_(signaling_thread),
|
|
session_desc_factory_(channel_manager,
|
|
&transport_desc_factory_,
|
|
ssrc_generator),
|
|
// RFC 4566 suggested a Network Time Protocol (NTP) format timestamp
|
|
// as the session id and session version. To simplify, it should be fine
|
|
// to just use a random number as session id and start version from
|
|
// |kInitSessionVersion|.
|
|
session_version_(kInitSessionVersion),
|
|
cert_generator_(std::move(cert_generator)),
|
|
pc_(pc),
|
|
session_id_(session_id),
|
|
certificate_request_state_(CERTIFICATE_NOT_NEEDED) {
|
|
RTC_DCHECK(signaling_thread_);
|
|
RTC_DCHECK(!(cert_generator_ && certificate));
|
|
bool dtls_enabled = cert_generator_ || certificate;
|
|
// SRTP-SDES is disabled if DTLS is on.
|
|
SetSdesPolicy(dtls_enabled ? cricket::SEC_DISABLED : cricket::SEC_REQUIRED);
|
|
if (!dtls_enabled) {
|
|
RTC_LOG(LS_VERBOSE) << "DTLS-SRTP disabled.";
|
|
return;
|
|
}
|
|
|
|
if (certificate) {
|
|
// Use |certificate|.
|
|
certificate_request_state_ = CERTIFICATE_WAITING;
|
|
|
|
RTC_LOG(LS_VERBOSE) << "DTLS-SRTP enabled; has certificate parameter.";
|
|
// We already have a certificate but we wait to do |SetIdentity|; if we do
|
|
// it in the constructor then the caller has not had a chance to connect to
|
|
// |SignalCertificateReady|.
|
|
signaling_thread_->Post(
|
|
RTC_FROM_HERE, this, MSG_USE_CONSTRUCTOR_CERTIFICATE,
|
|
new rtc::ScopedRefMessageData<rtc::RTCCertificate>(certificate));
|
|
} else {
|
|
// Generate certificate.
|
|
certificate_request_state_ = CERTIFICATE_WAITING;
|
|
|
|
rtc::scoped_refptr<WebRtcCertificateGeneratorCallback> callback(
|
|
new rtc::RefCountedObject<WebRtcCertificateGeneratorCallback>());
|
|
callback->SignalRequestFailed.connect(
|
|
this, &WebRtcSessionDescriptionFactory::OnCertificateRequestFailed);
|
|
callback->SignalCertificateReady.connect(
|
|
this, &WebRtcSessionDescriptionFactory::SetCertificate);
|
|
|
|
rtc::KeyParams key_params = rtc::KeyParams();
|
|
RTC_LOG(LS_VERBOSE)
|
|
<< "DTLS-SRTP enabled; sending DTLS identity request (key type: "
|
|
<< key_params.type() << ").";
|
|
|
|
// Request certificate. This happens asynchronously, so that the caller gets
|
|
// a chance to connect to |SignalCertificateReady|.
|
|
cert_generator_->GenerateCertificateAsync(key_params, absl::nullopt,
|
|
callback);
|
|
}
|
|
}
|
|
|
|
WebRtcSessionDescriptionFactory::~WebRtcSessionDescriptionFactory() {
|
|
RTC_DCHECK(signaling_thread_->IsCurrent());
|
|
|
|
// Fail any requests that were asked for before identity generation completed.
|
|
FailPendingRequests(kFailedDueToSessionShutdown);
|
|
|
|
// Process all pending notifications in the message queue. If we don't do
|
|
// this, requests will linger and not know they succeeded or failed.
|
|
rtc::MessageList list;
|
|
signaling_thread_->Clear(this, rtc::MQID_ANY, &list);
|
|
for (auto& msg : list) {
|
|
if (msg.message_id != MSG_USE_CONSTRUCTOR_CERTIFICATE) {
|
|
OnMessage(&msg);
|
|
} else {
|
|
// Skip MSG_USE_CONSTRUCTOR_CERTIFICATE because we don't want to trigger
|
|
// SetIdentity-related callbacks in the destructor. This can be a problem
|
|
// when WebRtcSession listens to the callback but it was the WebRtcSession
|
|
// destructor that caused WebRtcSessionDescriptionFactory's destruction.
|
|
// The callback is then ignored, leaking memory allocated by OnMessage for
|
|
// MSG_USE_CONSTRUCTOR_CERTIFICATE.
|
|
delete msg.pdata;
|
|
}
|
|
}
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::CreateOffer(
|
|
CreateSessionDescriptionObserver* observer,
|
|
const PeerConnectionInterface::RTCOfferAnswerOptions& options,
|
|
const cricket::MediaSessionOptions& session_options) {
|
|
std::string error = "CreateOffer";
|
|
if (certificate_request_state_ == CERTIFICATE_FAILED) {
|
|
error += kFailedDueToIdentityFailed;
|
|
RTC_LOG(LS_ERROR) << error;
|
|
PostCreateSessionDescriptionFailed(observer, error);
|
|
return;
|
|
}
|
|
|
|
if (!ValidMediaSessionOptions(session_options)) {
|
|
error += " called with invalid session options";
|
|
RTC_LOG(LS_ERROR) << error;
|
|
PostCreateSessionDescriptionFailed(observer, error);
|
|
return;
|
|
}
|
|
|
|
CreateSessionDescriptionRequest request(
|
|
CreateSessionDescriptionRequest::kOffer, observer, session_options);
|
|
if (certificate_request_state_ == CERTIFICATE_WAITING) {
|
|
create_session_description_requests_.push(request);
|
|
} else {
|
|
RTC_DCHECK(certificate_request_state_ == CERTIFICATE_SUCCEEDED ||
|
|
certificate_request_state_ == CERTIFICATE_NOT_NEEDED);
|
|
InternalCreateOffer(request);
|
|
}
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::CreateAnswer(
|
|
CreateSessionDescriptionObserver* observer,
|
|
const cricket::MediaSessionOptions& session_options) {
|
|
std::string error = "CreateAnswer";
|
|
if (certificate_request_state_ == CERTIFICATE_FAILED) {
|
|
error += kFailedDueToIdentityFailed;
|
|
RTC_LOG(LS_ERROR) << error;
|
|
PostCreateSessionDescriptionFailed(observer, error);
|
|
return;
|
|
}
|
|
if (!pc_->remote_description()) {
|
|
error += " can't be called before SetRemoteDescription.";
|
|
RTC_LOG(LS_ERROR) << error;
|
|
PostCreateSessionDescriptionFailed(observer, error);
|
|
return;
|
|
}
|
|
if (pc_->remote_description()->GetType() != SdpType::kOffer) {
|
|
error += " failed because remote_description is not an offer.";
|
|
RTC_LOG(LS_ERROR) << error;
|
|
PostCreateSessionDescriptionFailed(observer, error);
|
|
return;
|
|
}
|
|
|
|
if (!ValidMediaSessionOptions(session_options)) {
|
|
error += " called with invalid session options.";
|
|
RTC_LOG(LS_ERROR) << error;
|
|
PostCreateSessionDescriptionFailed(observer, error);
|
|
return;
|
|
}
|
|
|
|
CreateSessionDescriptionRequest request(
|
|
CreateSessionDescriptionRequest::kAnswer, observer, session_options);
|
|
if (certificate_request_state_ == CERTIFICATE_WAITING) {
|
|
create_session_description_requests_.push(request);
|
|
} else {
|
|
RTC_DCHECK(certificate_request_state_ == CERTIFICATE_SUCCEEDED ||
|
|
certificate_request_state_ == CERTIFICATE_NOT_NEEDED);
|
|
InternalCreateAnswer(request);
|
|
}
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::SetSdesPolicy(
|
|
cricket::SecurePolicy secure_policy) {
|
|
session_desc_factory_.set_secure(secure_policy);
|
|
}
|
|
|
|
cricket::SecurePolicy WebRtcSessionDescriptionFactory::SdesPolicy() const {
|
|
return session_desc_factory_.secure();
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::OnMessage(rtc::Message* msg) {
|
|
switch (msg->message_id) {
|
|
case MSG_CREATE_SESSIONDESCRIPTION_SUCCESS: {
|
|
CreateSessionDescriptionMsg* param =
|
|
static_cast<CreateSessionDescriptionMsg*>(msg->pdata);
|
|
param->observer->OnSuccess(param->description.release());
|
|
delete param;
|
|
break;
|
|
}
|
|
case MSG_CREATE_SESSIONDESCRIPTION_FAILED: {
|
|
CreateSessionDescriptionMsg* param =
|
|
static_cast<CreateSessionDescriptionMsg*>(msg->pdata);
|
|
param->observer->OnFailure(std::move(param->error));
|
|
delete param;
|
|
break;
|
|
}
|
|
case MSG_USE_CONSTRUCTOR_CERTIFICATE: {
|
|
rtc::ScopedRefMessageData<rtc::RTCCertificate>* param =
|
|
static_cast<rtc::ScopedRefMessageData<rtc::RTCCertificate>*>(
|
|
msg->pdata);
|
|
RTC_LOG(LS_INFO) << "Using certificate supplied to the constructor.";
|
|
SetCertificate(param->data());
|
|
delete param;
|
|
break;
|
|
}
|
|
default:
|
|
RTC_NOTREACHED();
|
|
break;
|
|
}
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::InternalCreateOffer(
|
|
CreateSessionDescriptionRequest request) {
|
|
if (pc_->local_description()) {
|
|
// If the needs-ice-restart flag is set as described by JSEP, we should
|
|
// generate an offer with a new ufrag/password to trigger an ICE restart.
|
|
for (cricket::MediaDescriptionOptions& options :
|
|
request.options.media_description_options) {
|
|
if (pc_->NeedsIceRestart(options.mid)) {
|
|
options.transport_options.ice_restart = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
std::unique_ptr<cricket::SessionDescription> desc =
|
|
session_desc_factory_.CreateOffer(
|
|
request.options, pc_->local_description()
|
|
? pc_->local_description()->description()
|
|
: nullptr);
|
|
if (!desc) {
|
|
PostCreateSessionDescriptionFailed(request.observer,
|
|
"Failed to initialize the offer.");
|
|
return;
|
|
}
|
|
|
|
// RFC 3264
|
|
// When issuing an offer that modifies the session,
|
|
// the "o=" line of the new SDP MUST be identical to that in the
|
|
// previous SDP, except that the version in the origin field MUST
|
|
// increment by one from the previous SDP.
|
|
|
|
// Just increase the version number by one each time when a new offer
|
|
// is created regardless if it's identical to the previous one or not.
|
|
// The |session_version_| is a uint64_t, the wrap around should not happen.
|
|
RTC_DCHECK(session_version_ + 1 > session_version_);
|
|
auto offer = std::make_unique<JsepSessionDescription>(
|
|
SdpType::kOffer, std::move(desc), session_id_,
|
|
rtc::ToString(session_version_++));
|
|
if (pc_->local_description()) {
|
|
for (const cricket::MediaDescriptionOptions& options :
|
|
request.options.media_description_options) {
|
|
if (!options.transport_options.ice_restart) {
|
|
CopyCandidatesFromSessionDescription(pc_->local_description(),
|
|
options.mid, offer.get());
|
|
}
|
|
}
|
|
}
|
|
PostCreateSessionDescriptionSucceeded(request.observer, std::move(offer));
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::InternalCreateAnswer(
|
|
CreateSessionDescriptionRequest request) {
|
|
if (pc_->remote_description()) {
|
|
for (cricket::MediaDescriptionOptions& options :
|
|
request.options.media_description_options) {
|
|
// According to http://tools.ietf.org/html/rfc5245#section-9.2.1.1
|
|
// an answer should also contain new ICE ufrag and password if an offer
|
|
// has been received with new ufrag and password.
|
|
options.transport_options.ice_restart =
|
|
pc_->IceRestartPending(options.mid);
|
|
// We should pass the current SSL role to the transport description
|
|
// factory, if there is already an existing ongoing session.
|
|
rtc::SSLRole ssl_role;
|
|
if (pc_->GetSslRole(options.mid, &ssl_role)) {
|
|
options.transport_options.prefer_passive_role =
|
|
(rtc::SSL_SERVER == ssl_role);
|
|
}
|
|
}
|
|
}
|
|
|
|
std::unique_ptr<cricket::SessionDescription> desc =
|
|
session_desc_factory_.CreateAnswer(
|
|
pc_->remote_description() ? pc_->remote_description()->description()
|
|
: nullptr,
|
|
request.options,
|
|
pc_->local_description() ? pc_->local_description()->description()
|
|
: nullptr);
|
|
if (!desc) {
|
|
PostCreateSessionDescriptionFailed(request.observer,
|
|
"Failed to initialize the answer.");
|
|
return;
|
|
}
|
|
|
|
// RFC 3264
|
|
// If the answer is different from the offer in any way (different IP
|
|
// addresses, ports, etc.), the origin line MUST be different in the answer.
|
|
// In that case, the version number in the "o=" line of the answer is
|
|
// unrelated to the version number in the o line of the offer.
|
|
// Get a new version number by increasing the |session_version_answer_|.
|
|
// The |session_version_| is a uint64_t, the wrap around should not happen.
|
|
RTC_DCHECK(session_version_ + 1 > session_version_);
|
|
auto answer = std::make_unique<JsepSessionDescription>(
|
|
SdpType::kAnswer, std::move(desc), session_id_,
|
|
rtc::ToString(session_version_++));
|
|
if (pc_->local_description()) {
|
|
// Include all local ICE candidates in the SessionDescription unless
|
|
// the remote peer has requested an ICE restart.
|
|
for (const cricket::MediaDescriptionOptions& options :
|
|
request.options.media_description_options) {
|
|
if (!options.transport_options.ice_restart) {
|
|
CopyCandidatesFromSessionDescription(pc_->local_description(),
|
|
options.mid, answer.get());
|
|
}
|
|
}
|
|
}
|
|
PostCreateSessionDescriptionSucceeded(request.observer, std::move(answer));
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::FailPendingRequests(
|
|
const std::string& reason) {
|
|
RTC_DCHECK(signaling_thread_->IsCurrent());
|
|
while (!create_session_description_requests_.empty()) {
|
|
const CreateSessionDescriptionRequest& request =
|
|
create_session_description_requests_.front();
|
|
PostCreateSessionDescriptionFailed(
|
|
request.observer,
|
|
((request.type == CreateSessionDescriptionRequest::kOffer)
|
|
? "CreateOffer"
|
|
: "CreateAnswer") +
|
|
reason);
|
|
create_session_description_requests_.pop();
|
|
}
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::PostCreateSessionDescriptionFailed(
|
|
CreateSessionDescriptionObserver* observer,
|
|
const std::string& error) {
|
|
CreateSessionDescriptionMsg* msg = new CreateSessionDescriptionMsg(
|
|
observer, RTCError(RTCErrorType::INTERNAL_ERROR, std::string(error)));
|
|
signaling_thread_->Post(RTC_FROM_HERE, this,
|
|
MSG_CREATE_SESSIONDESCRIPTION_FAILED, msg);
|
|
RTC_LOG(LS_ERROR) << "Create SDP failed: " << error;
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::PostCreateSessionDescriptionSucceeded(
|
|
CreateSessionDescriptionObserver* observer,
|
|
std::unique_ptr<SessionDescriptionInterface> description) {
|
|
CreateSessionDescriptionMsg* msg =
|
|
new CreateSessionDescriptionMsg(observer, RTCError::OK());
|
|
msg->description = std::move(description);
|
|
signaling_thread_->Post(RTC_FROM_HERE, this,
|
|
MSG_CREATE_SESSIONDESCRIPTION_SUCCESS, msg);
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::OnCertificateRequestFailed() {
|
|
RTC_DCHECK(signaling_thread_->IsCurrent());
|
|
|
|
RTC_LOG(LS_ERROR) << "Asynchronous certificate generation request failed.";
|
|
certificate_request_state_ = CERTIFICATE_FAILED;
|
|
|
|
FailPendingRequests(kFailedDueToIdentityFailed);
|
|
}
|
|
|
|
void WebRtcSessionDescriptionFactory::SetCertificate(
|
|
const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) {
|
|
RTC_DCHECK(certificate);
|
|
RTC_LOG(LS_VERBOSE) << "Setting new certificate.";
|
|
|
|
certificate_request_state_ = CERTIFICATE_SUCCEEDED;
|
|
SignalCertificateReady(certificate);
|
|
|
|
transport_desc_factory_.set_certificate(certificate);
|
|
transport_desc_factory_.set_secure(cricket::SEC_ENABLED);
|
|
|
|
while (!create_session_description_requests_.empty()) {
|
|
if (create_session_description_requests_.front().type ==
|
|
CreateSessionDescriptionRequest::kOffer) {
|
|
InternalCreateOffer(create_session_description_requests_.front());
|
|
} else {
|
|
InternalCreateAnswer(create_session_description_requests_.front());
|
|
}
|
|
create_session_description_requests_.pop();
|
|
}
|
|
}
|
|
} // namespace webrtc
|