/*
* Copyright 2020 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/sdp_offer_answer.h"
#include <algorithm>
#include <cstddef>
#include <cstdint>
#include <functional>
#include <iterator>
#include <map>
#include <memory>
#include <optional>
#include <queue>
#include <set>
#include <string>
#include <utility>
#include <vector>
#include "absl/algorithm/container.h"
#include "absl/memory/memory.h"
#include "absl/strings/match.h"
#include "absl/strings/string_view.h"
#include "api/array_view.h"
#include "api/candidate.h"
#include "api/crypto/crypto_options.h"
#include "api/jsep.h"
#include "api/jsep_ice_candidate.h"
#include "api/make_ref_counted.h"
#include "api/media_stream_interface.h"
#include "api/media_types.h"
#include "api/peer_connection_interface.h"
#include "api/rtc_error.h"
#include "api/rtp_parameters.h"
#include "api/rtp_receiver_interface.h"
#include "api/rtp_sender_interface.h"
#include "api/rtp_transceiver_direction.h"
#include "api/rtp_transceiver_interface.h"
#include "api/scoped_refptr.h"
#include "api/sequence_checker.h"
#include "api/set_local_description_observer_interface.h"
#include "api/set_remote_description_observer_interface.h"
#include "api/uma_metrics.h"
#include "api/video/builtin_video_bitrate_allocator_factory.h"
#include "api/video/video_codec_constants.h"
#include "call/payload_type.h"
#include "media/base/codec.h"
#include "media/base/media_engine.h"
#include "media/base/rid_description.h"
#include "media/base/stream_params.h"
#include "p2p/base/ice_transport_internal.h"
#include "p2p/base/p2p_constants.h"
#include "p2p/base/p2p_transport_channel.h"
#include "p2p/base/port_allocator.h"
#include "p2p/base/transport_description.h"
#include "p2p/base/transport_description_factory.h"
#include "p2p/base/transport_info.h"
#include "pc/channel_interface.h"
#include "pc/connection_context.h"
#include "pc/dtls_transport.h"
#include "pc/jsep_transport_controller.h"
#include "pc/legacy_stats_collector.h"
#include "pc/media_session.h"
#include "pc/media_stream.h"
#include "pc/media_stream_observer.h"
#include "pc/media_stream_proxy.h"
#include "pc/peer_connection_internal.h"
#include "pc/peer_connection_message_handler.h"
#include "pc/rtp_media_utils.h"
#include "pc/rtp_receiver.h"
#include "pc/rtp_sender.h"
#include "pc/rtp_sender_proxy.h"
#include "pc/rtp_transceiver.h"
#include "pc/rtp_transmission_manager.h"
#include "pc/session_description.h"
#include "pc/simulcast_description.h"
#include "pc/stream_collection.h"
#include "pc/transceiver_list.h"
#include "pc/usage_pattern.h"
#include "pc/used_ids.h"
#include "pc/webrtc_session_description_factory.h"
#include "rtc_base/checks.h"
#include "rtc_base/crypto_random.h"
#include "rtc_base/logging.h"
#include "rtc_base/operations_chain.h"
#include "rtc_base/rtc_certificate.h"
#include "rtc_base/ssl_stream_adapter.h"
#include "rtc_base/string_encode.h"
#include "rtc_base/strings/string_builder.h"
#include "rtc_base/thread.h"
#include "rtc_base/trace_event.h"
#include "rtc_base/weak_ptr.h"
#include "system_wrappers/include/metrics.h"
using cricket::ContentInfo;
using cricket::ContentInfos;
using cricket::MediaContentDescription;
using cricket::MediaProtocolType;
using cricket::RidDescription;
using cricket::RidDirection;
using cricket::SessionDescription;
using cricket::SimulcastDescription;
using cricket::SimulcastLayer;
using cricket::SimulcastLayerList;
using cricket::StreamParams;
using cricket::TransportInfo;
namespace webrtc {
namespace {
typedef PeerConnectionInterface::RTCOfferAnswerOptions RTCOfferAnswerOptions;
// Error messages
const char kInvalidSdp[] =
"Invalid session description.";
const char kInvalidCandidates[] =
"Description contains invalid candidates.";
const char kBundleWithoutRtcpMux[] =
"rtcp-mux must be enabled when BUNDLE "
"is enabled.";
const char kMlineMismatchInAnswer[] =
"The order of m-lines in answer doesn't match order in offer. Rejecting "
"answer.";
const char kMlineMismatchInSubsequentOffer[] =
"The order of m-lines in subsequent offer doesn't match order from "
"previous offer/answer.";
const char kSdpWithoutIceUfragPwd[] =
"Called with SDP without ice-ufrag and ice-pwd.";
const char kSdpWithoutDtlsFingerprint[] =
"Called with SDP without DTLS fingerprint.";
const char kSdpWithoutCrypto[] =
"Called with SDP without crypto setup.";
const char kSessionError[] =
"Session error code: ";
const char kSessionErrorDesc[] =
"Session error description: ";
// The length of RTCP CNAMEs.
static const int kRtcpCnameLength = 16;
// The maximum length of the MID attribute.
static constexpr size_t kMidMaxSize = 16;
const char kDefaultStreamId[] =
"default";
// NOTE: Duplicated in peer_connection.cc:
static const char kDefaultAudioSenderId[] =
"defaulta0";
static const char kDefaultVideoSenderId[] =
"defaultv0";
void NoteAddIceCandidateResult(
int result) {
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.PeerConnection.AddIceCandidate", result,
kAddIceCandidateMax);
}
std::map<std::string,
const cricket::ContentGroup*> GetBundleGroupsByMid(
const SessionDescription* desc) {
std::vector<
const cricket::ContentGroup*> bundle_groups =
desc->GetGroupsByName(cricket::GROUP_TYPE_BUNDLE);
std::map<std::string,
const cricket::ContentGroup*> bundle_groups_by_mid;
for (
const cricket::ContentGroup* bundle_group : bundle_groups) {
for (
const std::string& content_name : bundle_group->content_names()) {
bundle_groups_by_mid[content_name] = bundle_group;
}
}
return bundle_groups_by_mid;
}
// Returns true if `new_desc` requests an ICE restart (i.e., new ufrag/pwd).
bool CheckForRemoteIceRestart(
const SessionDescriptionInterface* old_desc,
const SessionDescriptionInterface* new_desc,
const std::string& content_name) {
if (!old_desc) {
return false;
}
const SessionDescription* new_sd = new_desc->description();
const SessionDescription* old_sd = old_desc->description();
const ContentInfo* cinfo = new_sd->GetContentByName(content_name);
if (!cinfo || cinfo->rejected) {
return false;
}
// If the content isn't rejected, check if ufrag and password has changed.
const cricket::TransportDescription* new_transport_desc =
new_sd->GetTransportDescriptionByName(content_name);
const cricket::TransportDescription* old_transport_desc =
old_sd->GetTransportDescriptionByName(content_name);
if (!new_transport_desc || !old_transport_desc) {
// No transport description exists. This is not an ICE restart.
return false;
}
if (cricket::IceCredentialsChanged(
old_transport_desc->ice_ufrag, old_transport_desc->ice_pwd,
new_transport_desc->ice_ufrag, new_transport_desc->ice_pwd)) {
RTC_LOG(LS_INFO) <<
"Remote peer requests ICE restart for " << content_name
<<
".";
return true;
}
return false;
}
// Generates a string error message for SetLocalDescription/SetRemoteDescription
// from an RTCError.
std::string GetSetDescriptionErrorMessage(cricket::ContentSource source,
SdpType type,
const RTCError& error) {
rtc::StringBuilder oss;
oss <<
"Failed to set " << (source == cricket::CS_LOCAL ?
"local" :
"remote")
<<
" " << SdpTypeToString(type) <<
" sdp: ";
RTC_DCHECK(!absl::StartsWith(error.message(), oss.str())) << error.message();
oss << error.message();
return oss.Release();
}
std::string GetStreamIdsString(rtc::ArrayView<
const std::string> stream_ids) {
std::string output =
"streams=[";
const char* separator =
"";
for (
const auto& stream_id : stream_ids) {
output.append(separator).append(stream_id);
separator =
", ";
}
output.append(
"]");
return output;
}
const ContentInfo* FindTransceiverMSection(
RtpTransceiver* transceiver,
const SessionDescriptionInterface* session_description) {
return transceiver->mid()
? session_description->description()->GetContentByName(
*transceiver->mid())
: nullptr;
}
// If the direction is "recvonly" or "inactive", treat the description
// as containing no streams.
// See: https://code.google.com/p/webrtc/issues/detail?id=5054
std::vector<cricket::StreamParams> GetActiveStreams(
const cricket::MediaContentDescription* desc) {
return RtpTransceiverDirectionHasSend(desc->direction())
? desc->streams()
: std::vector<cricket::StreamParams>();
}
// Logic to decide if an m= section can be recycled. This means that the new
// m= section is not rejected, but the old local or remote m= section is
// rejected. `old_content_one` and `old_content_two` refer to the m= section
// of the old remote and old local descriptions in no particular order.
// We need to check both the old local and remote because either
// could be the most current from the latest negotation.
bool IsMediaSectionBeingRecycled(SdpType type,
const ContentInfo& content,
const ContentInfo* old_content_one,
const ContentInfo* old_content_two) {
return type == SdpType::kOffer && !content.rejected &&
((old_content_one && old_content_one->rejected) ||
(old_content_two && old_content_two->rejected));
}
// Verify that the order of media sections in `new_desc` matches
// `current_desc`. The number of m= sections in `new_desc` should be no
// less than `current_desc`. In the case of checking an answer's
// `new_desc`, the `current_desc` is the last offer that was set as the
// local or remote. In the case of checking an offer's `new_desc` we
// check against the local and remote descriptions stored from the last
// negotiation, because either of these could be the most up to date for
// possible rejected m sections. These are the `current_desc` and
// `secondary_current_desc`.
bool MediaSectionsInSameOrder(
const SessionDescription& current_desc,
const SessionDescription* secondary_current_desc,
const SessionDescription& new_desc,
const SdpType type) {
if (current_desc.contents().size() > new_desc.contents().size()) {
return false;
}
for (size_t i = 0; i < current_desc.contents().size(); ++i) {
const cricket::ContentInfo* secondary_content_info = nullptr;
if (secondary_current_desc &&
i < secondary_current_desc->contents().size()) {
secondary_content_info = &secondary_current_desc->contents()[i];
}
if (IsMediaSectionBeingRecycled(type, new_desc.contents()[i],
¤t_desc.contents()[i],
secondary_content_info)) {
// For new offer descriptions, if the media section can be recycled, it's
// valid for the MID and media type to change.
continue;
}
if (new_desc.contents()[i].name != current_desc.contents()[i].name) {
return false;
}
const MediaContentDescription* new_desc_mdesc =
new_desc.contents()[i].media_description();
const MediaContentDescription* current_desc_mdesc =
current_desc.contents()[i].media_description();
if (new_desc_mdesc->type() != current_desc_mdesc->type()) {
return false;
}
}
return true;
}
bool MediaSectionsHaveSameCount(
const SessionDescription& desc1,
const SessionDescription& desc2) {
return desc1.contents().size() == desc2.contents().size();
}
// Checks that each non-rejected content has a DTLS
// fingerprint, unless it's in a BUNDLE group, in which case only the
// BUNDLE-tag section (first media section/description in the BUNDLE group)
// needs a ufrag and pwd. Mismatches, such as replying with a DTLS fingerprint
// to SDES keys, will be caught in JsepTransport negotiation, and backstopped
// by Channel's `srtp_required` check.
RTCError VerifyCrypto(
const SessionDescription* desc,
bool dtls_enabled,
const std::map<std::string,
const cricket::ContentGroup*>&
bundle_groups_by_mid) {
for (
const cricket::ContentInfo& content_info : desc->contents()) {
if (content_info.rejected) {
continue;
}
const std::string& mid = content_info.name;
auto it = bundle_groups_by_mid.find(mid);
const cricket::ContentGroup* bundle =
it != bundle_groups_by_mid.end() ? it->second : nullptr;
if (bundle && mid != *(bundle->FirstContentName())) {
// This isn't the first media section in the BUNDLE group, so it's not
// required to have crypto attributes, since only the crypto attributes
// from the first section actually get used.
continue;
}
// If the content isn't rejected or bundled into another m= section, crypto
// must be present.
const MediaContentDescription* media = content_info.media_description();
const TransportInfo* tinfo = desc->GetTransportInfoByName(mid);
if (!media || !tinfo) {
// Something is not right.
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER, kInvalidSdp);
}
if (dtls_enabled) {
if (!tinfo->description.identity_fingerprint) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
kSdpWithoutDtlsFingerprint);
}
}
else {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER, kSdpWithoutCrypto);
}
}
return RTCError::OK();
}
// Checks that each non-rejected content has ice-ufrag and ice-pwd set, unless
// it's in a BUNDLE group, in which case only the BUNDLE-tag section (first
// media section/description in the BUNDLE group) needs a ufrag and pwd.
bool VerifyIceUfragPwdPresent(
const SessionDescription* desc,
const std::map<std::string,
const cricket::ContentGroup*>&
bundle_groups_by_mid) {
for (
const cricket::ContentInfo& content_info : desc->contents()) {
if (content_info.rejected) {
continue;
}
const std::string& mid = content_info.name;
auto it = bundle_groups_by_mid.find(mid);
const cricket::ContentGroup* bundle =
it != bundle_groups_by_mid.end() ? it->second : nullptr;
if (bundle && mid != *(bundle->FirstContentName())) {
// This isn't the first media section in the BUNDLE group, so it's not
// required to have ufrag/password, since only the ufrag/password from
// the first section actually get used.
continue;
}
// If the content isn't rejected or bundled into another m= section,
// ice-ufrag and ice-pwd must be present.
const TransportInfo* tinfo = desc->GetTransportInfoByName(mid);
if (!tinfo) {
// Something is not right.
RTC_LOG(LS_ERROR) << kInvalidSdp;
return false;
}
if (tinfo->description.ice_ufrag.empty() ||
tinfo->description.ice_pwd.empty()) {
RTC_LOG(LS_ERROR) <<
"Session description must have ice ufrag and pwd.";
return false;
}
}
return true;
}
RTCError ValidateMids(
const cricket::SessionDescription& description) {
std::set<std::string> mids;
for (
const cricket::ContentInfo& content : description.contents()) {
if (content.name.empty()) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"A media section is missing a MID attribute.");
}
if (content.name.size() > kMidMaxSize) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"The MID attribute exceeds the maximum supported "
"length of 16 characters.");
}
if (!mids.insert(content.name).second) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"Duplicate a=mid value '" + content.name +
"'.");
}
}
return RTCError::OK();
}
RTCError FindDuplicateCodecParameters(
const RtpCodecParameters codec_parameters,
std::map<
int, RtpCodecParameters>& payload_to_codec_parameters) {
auto existing_codec_parameters =
payload_to_codec_parameters.find(codec_parameters.payload_type);
if (existing_codec_parameters != payload_to_codec_parameters.end() &&
codec_parameters != existing_codec_parameters->second) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"A BUNDLE group contains a codec collision for "
"payload_type='" +
rtc::ToString(codec_parameters.payload_type) +
". All codecs must share the same type, "
"encoding name, clock rate and parameters.");
}
payload_to_codec_parameters.insert(
std::make_pair(codec_parameters.payload_type, codec_parameters));
return RTCError::OK();
}
RTCError ValidateBundledPayloadTypes(
const cricket::SessionDescription& description) {
// https://www.rfc-editor.org/rfc/rfc8843#name-payload-type-pt-value-reuse
// ... all codecs associated with the payload type number MUST share an
// identical codec configuration. This means that the codecs MUST share
// the same media type, encoding name, clock rate, and any parameter
// that can affect the codec configuration and packetization.
std::vector<
const cricket::ContentGroup*> bundle_groups =
description.GetGroupsByName(cricket::GROUP_TYPE_BUNDLE);
for (
const cricket::ContentGroup* bundle_group : bundle_groups) {
std::map<
int, RtpCodecParameters> payload_to_codec_parameters;
for (
const std::string& content_name : bundle_group->content_names()) {
const ContentInfo* content_description =
description.GetContentByName(content_name);
if (!content_description) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"A BUNDLE group contains a MID='" + content_name +
"' matching no m= section.");
}
const cricket::MediaContentDescription* media_description =
content_description->media_description();
RTC_DCHECK(media_description);
if (content_description->rejected || !media_description ||
!media_description->has_codecs()) {
continue;
}
const auto type = media_description->type();
if (type == cricket::MEDIA_TYPE_AUDIO ||
type == cricket::MEDIA_TYPE_VIDEO) {
for (
const auto& c : media_description->codecs()) {
auto error = FindDuplicateCodecParameters(
c.ToCodecParameters(), payload_to_codec_parameters);
if (!error.ok()) {
return error;
}
}
}
}
}
return RTCError::OK();
}
RTCError FindDuplicateHeaderExtensionIds(
const RtpExtension extension,
std::map<
int, RtpExtension>& id_to_extension) {
auto existing_extension = id_to_extension.find(extension.id);
if (existing_extension != id_to_extension.end() &&
!(extension.uri == existing_extension->second.uri &&
extension.encrypt == existing_extension->second.encrypt)) {
LOG_AND_RETURN_ERROR(
RTCErrorType::INVALID_PARAMETER,
"A BUNDLE group contains a codec collision for "
"header extension id=" +
rtc::ToString(extension.id) +
". The id must be the same across all bundled media descriptions");
}
id_to_extension.insert(std::make_pair(extension.id, extension));
return RTCError::OK();
}
RTCError ValidateBundledRtpHeaderExtensions(
const cricket::SessionDescription& description) {
// https://www.rfc-editor.org/rfc/rfc8843#name-rtp-header-extensions-consi
// ... the identifier used for a given extension MUST identify the same
// extension across all the bundled media descriptions.
std::vector<
const cricket::ContentGroup*> bundle_groups =
description.GetGroupsByName(cricket::GROUP_TYPE_BUNDLE);
for (
const cricket::ContentGroup* bundle_group : bundle_groups) {
std::map<
int, RtpExtension> id_to_extension;
for (
const std::string& content_name : bundle_group->content_names()) {
const ContentInfo* content_description =
description.GetContentByName(content_name);
if (!content_description) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"A BUNDLE group contains a MID='" + content_name +
"' matching no m= section.");
}
const cricket::MediaContentDescription* media_description =
content_description->media_description();
RTC_DCHECK(media_description);
if (content_description->rejected || !media_description ||
!media_description->has_codecs()) {
continue;
}
for (
const auto& extension : media_description->rtp_header_extensions()) {
auto error =
FindDuplicateHeaderExtensionIds(extension, id_to_extension);
if (!error.ok()) {
return error;
}
}
}
}
return RTCError::OK();
}
RTCError ValidateRtpHeaderExtensionsForSpecSimulcast(
const cricket::SessionDescription& description) {
for (
const ContentInfo& content : description.contents()) {
if (content.type != MediaProtocolType::kRtp || content.rejected) {
continue;
}
const auto media_description = content.media_description();
if (!media_description->HasSimulcast()) {
continue;
}
auto extensions = media_description->rtp_header_extensions();
auto it = absl::c_find_if(extensions, [](
const RtpExtension& ext) {
return ext.uri == RtpExtension::kRidUri;
});
if (it == extensions.end()) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"The media section with MID='" + content.mid() +
"' negotiates simulcast but does not negotiate "
"the RID RTP header extension.");
}
}
return RTCError::OK();
}
RTCError ValidateSsrcGroups(
const cricket::SessionDescription& description) {
for (
const ContentInfo& content : description.contents()) {
if (content.type != MediaProtocolType::kRtp) {
continue;
}
for (
const StreamParams& stream : content.media_description()->streams()) {
for (
const cricket::SsrcGroup& group : stream.ssrc_groups) {
// Validate the number of SSRCs for standard SSRC group semantics such
// as FID and FEC-FR and the non-standard SIM group.
if ((group.semantics == cricket::kFidSsrcGroupSemantics &&
group.ssrcs.size() != 2) ||
(group.semantics == cricket::kFecFrSsrcGroupSemantics &&
group.ssrcs.size() != 2) ||
(group.semantics == cricket::kSimSsrcGroupSemantics &&
group.ssrcs.size() > kMaxSimulcastStreams)) {
LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER,
"The media section with MID='" + content.mid() +
"' has a ssrc-group with semantics " +
group.semantics +
" and an unexpected number of SSRCs.");
}
}
}
}
return RTCError::OK();
}
RTCError ValidatePayloadTypes(
const cricket::SessionDescription& description) {
for (
const ContentInfo& content : description.contents()) {
if (content.type != MediaProtocolType::kRtp) {
continue;
}
const auto media_description = content.media_description();
RTC_DCHECK(media_description);
if (content.rejected || !media_description ||
!media_description->has_codecs()) {
continue;
}
const auto type = media_description->type();
if (type == cricket::MEDIA_TYPE_AUDIO ||
type == cricket::MEDIA_TYPE_VIDEO) {
for (
const auto& codec : media_description->codecs()) {
if (!cricket::UsedPayloadTypes::IsIdValid(
codec, media_description->rtcp_mux())) {
LOG_AND_RETURN_ERROR(
RTCErrorType::INVALID_PARAMETER,
"The media section with MID='" + content.mid() +
"' used an invalid payload type " + rtc::ToString(codec.id) +
" for codec '" + codec.name +
", rtcp-mux:" +
(media_description->rtcp_mux() ?
"enabled" :
"disabled"));
}
}
}
}
return RTCError::OK();
}
bool IsValidOfferToReceiveMedia(
int value) {
typedef PeerConnectionInterface::RTCOfferAnswerOptions Options;
return (value >= Options::kUndefined) &&
(value <= Options::kMaxOfferToReceiveMedia);
}
bool ValidateOfferAnswerOptions(
const PeerConnectionInterface::RTCOfferAnswerOptions& rtc_options) {
return IsValidOfferToReceiveMedia(rtc_options.offer_to_receive_audio) &&
IsValidOfferToReceiveMedia(rtc_options.offer_to_receive_video);
}
// This method will extract any send encodings that were sent by the remote
// connection. This is currently only relevant for Simulcast scenario (where
// the number of layers may be communicated by the server).
std::vector<RtpEncodingParameters> GetSendEncodingsFromRemoteDescription(
const MediaContentDescription& desc) {
if (!desc.HasSimulcast()) {
return {};
}
std::vector<RtpEncodingParameters> result;
const SimulcastDescription& simulcast = desc.simulcast_description();
// This is a remote description, the parameters we are after should appear
// as receive streams.
for (
const auto& alternatives : simulcast.receive_layers()) {
RTC_DCHECK(!alternatives.empty());
// There is currently no way to specify or choose from alternatives.
// We will always use the first alternative, which is the most preferred.
const SimulcastLayer& layer = alternatives[0];
RtpEncodingParameters parameters;
parameters.rid = layer.rid;
parameters.active = !layer.is_paused;
// If a payload type has been specified for this rid, set the codec
// corresponding to that payload type.
auto rid_desc = std::find_if(
desc.receive_rids().begin(), desc.receive_rids().end(),
[&layer](
const RidDescription& rid) {
return rid.rid == layer.rid; })
;
if (rid_desc != desc.receive_rids().end() &&
!rid_desc->payload_types.empty()) {
int payload_type = rid_desc->payload_types[0];
auto codec = std::find_if(desc.codecs().begin(), desc.codecs().end(),
[payload_type](const cricket::Codec& codec) {
return codec.id == payload_type;
});
if (codec != desc.codecs().end()) {
parameters.codec = codec->ToCodecParameters();
}
}
result.push_back(parameters);
}
return result;
}
RTCError UpdateSimulcastLayerStatusInSender(
const std::vector<SimulcastLayer>& layers,
rtc::scoped_refptr<RtpSenderInternal> sender) {
RTC_DCHECK(sender);
RtpParameters parameters = sender->GetParametersInternalWithAllLayers();
std::vector<std::string> disabled_layers;
// The simulcast envelope cannot be changed, only the status of the streams.
// So we will iterate over the send encodings rather than the layers.
for (RtpEncodingParameters& encoding : parameters.encodings) {
auto iter = std::find_if(layers.begin(), layers.end(),
[&encoding](const SimulcastLayer& layer) {
return layer.rid == encoding.rid;
});
// A layer that cannot be found may have been removed by the remote party.
if (iter == layers.end()) {
disabled_layers.push_back(encoding.rid);
continue;
}
encoding.active = !iter->is_paused;
}
RTCError result = sender->SetParametersInternalWithAllLayers(parameters);
if (result.ok()) {
result = sender->DisableEncodingLayers(disabled_layers);
}
return result;
}
bool SimulcastIsRejected(const ContentInfo* local_content,
const MediaContentDescription& answer_media_desc,
bool enable_encrypted_rtp_header_extensions) {
bool simulcast_offered = local_content &&
local_content->media_description() &&
local_content->media_description()->HasSimulcast();
bool simulcast_answered = answer_media_desc.HasSimulcast();
bool rids_supported = RtpExtension::FindHeaderExtensionByUri(
answer_media_desc.rtp_header_extensions(), RtpExtension::kRidUri,
enable_encrypted_rtp_header_extensions
? RtpExtension::Filter::kPreferEncryptedExtension
: RtpExtension::Filter::kDiscardEncryptedExtension);
return simulcast_offered && (!simulcast_answered || !rids_supported);
}
RTCError DisableSimulcastInSender(
rtc::scoped_refptr<RtpSenderInternal> sender) {
RTC_DCHECK(sender);
RtpParameters parameters = sender->GetParametersInternalWithAllLayers();
if (parameters.encodings.size() <= 1) {
return RTCError::OK();
}
std::vector<std::string> disabled_layers;
std::transform(
parameters.encodings.begin() + 1, parameters.encodings.end(),
std::back_inserter(disabled_layers),
[](const RtpEncodingParameters& encoding) { return encoding.rid; });
return sender->DisableEncodingLayers(disabled_layers);
}
// The SDP parser used to populate these values by default for the 'content
// name' if an a=mid line was absent.
absl::string_view GetDefaultMidForPlanB(cricket::MediaType media_type) {
switch (media_type) {
case cricket::MEDIA_TYPE_AUDIO:
return cricket::CN_AUDIO;
case cricket::MEDIA_TYPE_VIDEO:
return cricket::CN_VIDEO;
case cricket::MEDIA_TYPE_DATA:
return cricket::CN_DATA;
case cricket::MEDIA_TYPE_UNSUPPORTED:
return "not supported";
}
RTC_DCHECK_NOTREACHED();
return "";
}
// Add options to |[audio/video]_media_description_options| from `senders`.
void AddPlanBRtpSenderOptions(
const std::vector<rtc::scoped_refptr<
RtpSenderProxyWithInternal<RtpSenderInternal>>>& senders,
cricket::MediaDescriptionOptions* audio_media_description_options,
cricket::MediaDescriptionOptions* video_media_description_options,
int num_sim_layers) {
for (const auto& sender : senders) {
if (sender->media_type() == cricket::MEDIA_TYPE_AUDIO) {
if (audio_media_description_options) {
audio_media_description_options->AddAudioSender(
sender->id(), sender->internal()->stream_ids());
}
} else {
RTC_DCHECK(sender->media_type() == cricket::MEDIA_TYPE_VIDEO);
if (video_media_description_options) {
video_media_description_options->AddVideoSender(
sender->id(), sender->internal()->stream_ids(), {},
SimulcastLayerList(), num_sim_layers);
}
}
}
}
cricket::MediaDescriptionOptions GetMediaDescriptionOptionsForTransceiver(
RtpTransceiver* transceiver,
const std::string& mid,
bool is_create_offer) {
// NOTE: a stopping transceiver should be treated as a stopped one in
// createOffer as specified in
// https://w3c.github.io/webrtc-pc/#dom-rtcpeerconnection-createoffer.
bool stopped =
is_create_offer ? transceiver->stopping() : transceiver->stopped();
cricket::MediaDescriptionOptions media_description_options(
transceiver->media_type(), mid, transceiver->direction(), stopped);
media_description_options.codec_preferences =
transceiver->codec_preferences();
media_description_options.header_extensions =
transceiver->GetHeaderExtensionsToNegotiate();
// This behavior is specified in JSEP. The gist is that:
// 1. The MSID is included if the RtpTransceiver's direction is sendonly or
// sendrecv.
// 2. If the MSID is included, then it must be included in any subsequent
// offer/answer exactly the same until the RtpTransceiver is stopped.
if (stopped || (!RtpTransceiverDirectionHasSend(transceiver->direction()) &&
!transceiver->has_ever_been_used_to_send())) {
return media_description_options;
}
cricket::SenderOptions sender_options;
sender_options.track_id = transceiver->sender()->id();
sender_options.stream_ids = transceiver->sender()->stream_ids();
// The following sets up RIDs and Simulcast.
// RIDs are included if Simulcast is requested or if any RID was specified.
RtpParameters send_parameters =
transceiver->sender_internal()->GetParametersInternalWithAllLayers();
bool has_rids = std::any_of(send_parameters.encodings.begin(),
send_parameters.encodings.end(),
[](const RtpEncodingParameters& encoding) {
return !encoding.rid.empty();
});
std::vector<RidDescription> send_rids;
SimulcastLayerList send_layers;
for (const RtpEncodingParameters& encoding : send_parameters.encodings) {
if (encoding.rid.empty()) {
continue;
}
auto send_rid = RidDescription(encoding.rid, RidDirection::kSend);
if (encoding.codec) {
auto send_codecs = transceiver->sender_internal()->GetSendCodecs();
for (const cricket::Codec& codec : send_codecs) {
if (codec.MatchesRtpCodec(*encoding.codec)) {
send_rid.payload_types.push_back(codec.id);
break;
}
}
}
send_rids.push_back(send_rid);
send_layers.AddLayer(SimulcastLayer(encoding.rid, !encoding.active));
}
if (has_rids) {
sender_options.rids = send_rids;
}
sender_options.simulcast_layers = send_layers;
// When RIDs are configured, we must set num_sim_layers to 0 to.
// Otherwise, num_sim_layers must be 1 because either there is no
// simulcast, or simulcast is acheived by munging the SDP.
sender_options.num_sim_layers = has_rids ? 0 : 1;
media_description_options.sender_options.push_back(sender_options);
return media_description_options;
}
// Returns the ContentInfo at mline index `i`, or null if none exists.
const ContentInfo* GetContentByIndex(const SessionDescriptionInterface* sdesc,
size_t i) {
if (!sdesc) {
return nullptr;
}
const ContentInfos& contents = sdesc->description()->contents();
return (i < contents.size() ? &contents[i] : nullptr);
}
// From `rtc_options`, fill parts of `session_options` shared by all generated
// m= sectionss (in other words, nothing that involves a map/array).
void ExtractSharedMediaSessionOptions(
const PeerConnectionInterface::RTCOfferAnswerOptions& rtc_options,
cricket::MediaSessionOptions* session_options) {
session_options->vad_enabled = rtc_options.voice_activity_detection;
session_options->bundle_enabled = rtc_options.use_rtp_mux;
session_options->raw_packetization_for_video =
rtc_options.raw_packetization_for_video;
}
// Generate a RTCP CNAME when a PeerConnection is created.
std::string GenerateRtcpCname() {
std::string cname;
if (!rtc::CreateRandomString(kRtcpCnameLength, &cname)) {
RTC_LOG(LS_ERROR) << "Failed to generate CNAME.";
RTC_DCHECK_NOTREACHED();
}
return cname;
}
// Check if we can send `new_stream` on a PeerConnection.
bool CanAddLocalMediaStream(StreamCollectionInterface* current_streams,
MediaStreamInterface* new_stream) {
if (!new_stream || !current_streams) {
return false;
}
if (current_streams->find(new_stream->id()) != nullptr) {
RTC_LOG(LS_ERROR) << "MediaStream with ID " << new_stream->id()
<< " is already added.";
return false;
}
return true;
}
rtc::scoped_refptr<DtlsTransport> LookupDtlsTransportByMid(
rtc::Thread* network_thread,
JsepTransportController* controller,
const std::string& mid) {
// TODO(tommi): Can we post this (and associated operations where this
// function is called) to the network thread and avoid this BlockingCall?
// We might be able to simplify a few things if we set the transport on
// the network thread and then update the implementation to check that
// the set_ and relevant get methods are always called on the network
// thread (we'll need to update proxy maps).
return network_thread->BlockingCall(
[controller, &mid] { return controller->LookupDtlsTransportByMid(mid); });
}
bool ContentHasHeaderExtension(const cricket::ContentInfo& content_info,
absl::string_view header_extension_uri) {
for (const RtpExtension& rtp_header_extension :
content_info.media_description()->rtp_header_extensions()) {
if (rtp_header_extension.uri == header_extension_uri) {
return true;
}
}
return false;
}
} // namespace
void UpdateRtpHeaderExtensionPreferencesFromSdpMunging(
const cricket::SessionDescription* description,
TransceiverList* transceivers) {
// This integrates the RTP Header Extension Control API and local SDP munging
// for backward compability reasons. If something was enabled in the local
// description via SDP munging, consider it non-stopped in the API as well
// so that is shows up in subsequent offers/answers.
RTC_DCHECK(description);
RTC_DCHECK(transceivers);
for (const auto& content : description->contents()) {
auto transceiver = transceivers->FindByMid(content.name);
if (!transceiver) {
continue;
}
auto extension_capabilities = transceiver->GetHeaderExtensionsToNegotiate();
// Set the capability of every extension we see here to "sendrecv".
for (auto& ext : content.media_description()->rtp_header_extensions()) {
auto it = absl::c_find_if(extension_capabilities,
[&ext](const RtpHeaderExtensionCapability c) {
return ext.uri == c.uri;
});
if (it != extension_capabilities.end()) {
it->direction = RtpTransceiverDirection::kSendRecv;
}
}
transceiver->SetHeaderExtensionsToNegotiate(extension_capabilities);
}
}
// This class stores state related to a SetRemoteDescription operation, captures
// and reports potential errors that might occur and makes sure to notify the
// observer of the operation and the operations chain of completion.
class SdpOfferAnswerHandler::RemoteDescriptionOperation {
public:
RemoteDescriptionOperation(
SdpOfferAnswerHandler* handler,
std::unique_ptr<SessionDescriptionInterface> desc,
rtc::scoped_refptr<SetRemoteDescriptionObserverInterface> observer,
std::function<void()> operations_chain_callback)
: handler_(handler),
desc_(std::move(desc)),
observer_(std::move(observer)),
operations_chain_callback_(std::move(operations_chain_callback)),
unified_plan_(handler_->IsUnifiedPlan()) {
if (!desc_) {
type_ = static_cast<SdpType>(-1);
InvalidParam("SessionDescription is NULL.");
} else {
type_ = desc_->GetType();
}
}
~RemoteDescriptionOperation() {
RTC_DCHECK_RUN_ON(handler_->signaling_thread());
SignalCompletion();
operations_chain_callback_();
}
bool ok() const { return error_.ok(); }
// Notifies the observer that the operation is complete and releases the
// reference to the observer.
void SignalCompletion() {
if (!observer_)
return;
if (!error_.ok() && type_ != static_cast<SdpType>(-1)) {
std::string error_message =
GetSetDescriptionErrorMessage(cricket::CS_REMOTE, type_, error_);
RTC_LOG(LS_ERROR) << error_message;
error_.set_message(error_message);
}
observer_->OnSetRemoteDescriptionComplete(error_);
observer_ = nullptr; // Only fire the notification once.
}
// If a session error has occurred the PeerConnection is in a possibly
// inconsistent state so fail right away.
bool HaveSessionError() {
RTC_DCHECK(ok());
if (handler_->session_error() != SessionError::kNone)
InternalError(handler_->GetSessionErrorMsg());
return !ok();
}
// Returns true if the operation was a rollback operation. If this function
// returns true, the caller should consider the operation complete. Otherwise
// proceed to the next step.
bool MaybeRollback() {
RTC_DCHECK_RUN_ON(handler_->signaling_thread());
RTC_DCHECK(ok());
if (type_ != SdpType::kRollback) {
// Check if we can do an implicit rollback.
if (type_ == SdpType::kOffer && unified_plan_ &&
handler_->pc_->configuration()->enable_implicit_rollback &&
handler_->signaling_state() ==
PeerConnectionInterface::kHaveLocalOffer) {
handler_->Rollback(type_);
}
return false;
}
if (unified_plan_) {
error_ = handler_->Rollback(type_);
} else if (type_ == SdpType::kRollback) {
Unsupported("Rollback not supported in Plan B");
}
return true;
}
// Report to UMA the format of the received offer or answer.
void ReportOfferAnswerUma() {
RTC_DCHECK(ok());
if (type_ == SdpType::kOffer || type_ == SdpType::kAnswer) {
handler_->pc_->ReportSdpBundleUsage(*desc_.get());
}
}
// Checks if the session description for the operation is valid. If not, the
// function captures error information and returns false. Note that if the
// return value is false, the operation should be considered done.
bool IsDescriptionValid() {
RTC_DCHECK_RUN_ON(handler_->signaling_thread());
RTC_DCHECK(ok());
RTC_DCHECK(bundle_groups_by_mid_.empty()) << "Already called?";
bundle_groups_by_mid_ = GetBundleGroupsByMid(description());
error_ = handler_->ValidateSessionDescription(
desc_.get(), cricket::CS_REMOTE, bundle_groups_by_mid_);
return ok();
}
// Transfers ownership of the session description object over to `handler_`.
bool ReplaceRemoteDescriptionAndCheckError() {
RTC_DCHECK_RUN_ON(handler_->signaling_thread());
RTC_DCHECK(ok());
RTC_DCHECK(desc_);
RTC_DCHECK(!replaced_remote_description_);
#if RTC_DCHECK_IS_ON
const auto* existing_remote_description = handler_->remote_description();
#endif
error_ = handler_->ReplaceRemoteDescription(std::move(desc_), type_,
&replaced_remote_description_);
if (ok()) {
#if RTC_DCHECK_IS_ON
// Sanity check that our `old_remote_description()` method always returns
// the same value as `remote_description()` did before the call to
// ReplaceRemoteDescription.
RTC_DCHECK_EQ(existing_remote_description, old_remote_description());
#endif
} else {
SetAsSessionError();
}
return ok();
}
bool UpdateChannels() {
RTC_DCHECK(ok());
RTC_DCHECK(!desc_) << "ReplaceRemoteDescription hasn't been called";
const auto* remote_description = handler_->remote_description();
const cricket::SessionDescription* session_desc =
remote_description->description();
// Transport and Media channels will be created only when offer is set.
if (unified_plan_) {
error_ = handler_->UpdateTransceiversAndDataChannels(
cricket::CS_REMOTE, *remote_description,
handler_->local_description(), old_remote_description(),
bundle_groups_by_mid_);
} else {
// Media channels will be created only when offer is set. These may use
// new transports just created by PushdownTransportDescription.
if (type_ == SdpType::kOffer) {
// TODO(mallinath) - Handle CreateChannel failure, as new local
// description is applied. Restore back to old description.
error_ = handler_->CreateChannels(*session_desc);
}
// Remove unused channels if MediaContentDescription is rejected.
handler_->RemoveUnusedChannels(session_desc);
}
return ok();
}
bool UpdateSessionState() {
RTC_DCHECK(ok());
error_ = handler_->UpdateSessionState(
type_, cricket::CS_REMOTE,
handler_->remote_description()->description(), bundle_groups_by_mid_);
if (!ok())
SetAsSessionError();
return ok();
}
bool UseCandidatesInRemoteDescription() {
RTC_DCHECK(ok());
if (handler_->local_description() &&
!handler_->UseCandidatesInRemoteDescription()) {
InvalidParam(kInvalidCandidates);
}
return ok();
}
// Convenience getter for desc_->GetType().
SdpType type() const { return type_; }
bool unified_plan() const { return unified_plan_; }
cricket::SessionDescription* description() { return desc_->description(); }
const SessionDescriptionInterface* old_remote_description() const {
RTC_DCHECK(!desc_) << "Called before replacing the remote description";
if (type_ == SdpType::kAnswer)
return replaced_remote_description_.get();
return replaced_remote_description_
? replaced_remote_description_.get()
: handler_->current_remote_description();
}
// Returns a reference to a cached map of bundle groups ordered by mid.
// Note that this will only be valid after a successful call to
// `IsDescriptionValid`.
const std::map<std::string, const cricket::ContentGroup*>&
bundle_groups_by_mid() const {
RTC_DCHECK(ok());
return bundle_groups_by_mid_;
}
private:
// Convenience methods for populating the embedded `error_` object.
void Unsupported(std::string message) {
SetError(RTCErrorType::UNSUPPORTED_OPERATION, std::move(message));
}
void InvalidParam(std::string message) {
SetError(RTCErrorType::INVALID_PARAMETER, std::move(message));
}
void InternalError(std::string message) {
SetError(RTCErrorType::INTERNAL_ERROR, std::move(message));
}
void SetError(RTCErrorType type, std::string message) {
RTC_DCHECK(ok()) << "Overwriting an existing error?";
error_ = RTCError(type, std::move(message));
}
// Called when the PeerConnection could be in an inconsistent state and we set
// the session error so that future calls to
// SetLocalDescription/SetRemoteDescription fail.
void SetAsSessionError() {
RTC_DCHECK(!ok());
handler_->SetSessionError(SessionError::kContent, error_.message());
}
SdpOfferAnswerHandler* const handler_;
std::unique_ptr<SessionDescriptionInterface> desc_;
// Keeps the replaced session description object alive while the operation
// is taking place since methods that depend on `old_remote_description()`
// for updating the state, need it.
std::unique_ptr<SessionDescriptionInterface> replaced_remote_description_;
rtc::scoped_refptr<SetRemoteDescriptionObserverInterface> observer_;
std::function<void()> operations_chain_callback_;
RTCError error_ = RTCError::OK();
std::map<std::string, const cricket::ContentGroup*> bundle_groups_by_mid_;
SdpType type_;
const bool unified_plan_;
};
// Used by parameterless SetLocalDescription() to create an offer or answer.
// Upon completion of creating the session description, SetLocalDescription() is
// invoked with the result.
class SdpOfferAnswerHandler::ImplicitCreateSessionDescriptionObserver
: public CreateSessionDescriptionObserver {
public:
ImplicitCreateSessionDescriptionObserver(
rtc::WeakPtr<SdpOfferAnswerHandler> sdp_handler,
rtc::scoped_refptr<SetLocalDescriptionObserverInterface>
set_local_description_observer)
: sdp_handler_(std::move(sdp_handler)),
set_local_description_observer_(
std::move(set_local_description_observer)) {}
~ImplicitCreateSessionDescriptionObserver() override {
RTC_DCHECK(was_called_);
}
void SetOperationCompleteCallback(
std::function<void()> operation_complete_callback) {
operation_complete_callback_ = std::move(operation_complete_callback);
}
bool was_called() const { return was_called_; }
void OnSuccess(SessionDescriptionInterface* desc_ptr) override {
RTC_DCHECK(!was_called_);
std::unique_ptr<SessionDescriptionInterface> desc(desc_ptr);
was_called_ = true;
// Abort early if `pc_` is no longer valid.
if (!sdp_handler_) {
operation_complete_callback_();
return;
}
// DoSetLocalDescription() is a synchronous operation that invokes
// `set_local_description_observer_` with the result.
sdp_handler_->DoSetLocalDescription(
std::move(desc), std::move(set_local_description_observer_));
operation_complete_callback_();
}
void OnFailure(RTCError error) override {
RTC_DCHECK(!was_called_);
was_called_ = true;
set_local_description_observer_->OnSetLocalDescriptionComplete(RTCError(
error.type(), std::string("SetLocalDescription failed to create "
"session description - ") +
error.message()));
operation_complete_callback_();
}
private:
bool was_called_ = false;
rtc::WeakPtr<SdpOfferAnswerHandler> sdp_handler_;
rtc::scoped_refptr<SetLocalDescriptionObserverInterface>
set_local_description_observer_;
std::function<void()> operation_complete_callback_;
};
// Wraps a CreateSessionDescriptionObserver and an OperationsChain operation
// complete callback. When the observer is invoked, the wrapped observer is
// invoked followed by invoking the completion callback.
class CreateSessionDescriptionObserverOperationWrapper
: public CreateSessionDescriptionObserver {
public:
CreateSessionDescriptionObserverOperationWrapper(
rtc::scoped_refptr<CreateSessionDescriptionObserver> observer,
std::function<void()> operation_complete_callback)
: observer_(std::move(observer)),
operation_complete_callback_(std::move(operation_complete_callback)) {
RTC_DCHECK(observer_);
}
~CreateSessionDescriptionObserverOperationWrapper() override {
#if RTC_DCHECK_IS_ON
RTC_DCHECK(was_called_);
#endif
}
void OnSuccess(SessionDescriptionInterface* desc) override {
#if RTC_DCHECK_IS_ON
RTC_DCHECK(!was_called_);
was_called_ = true;
#endif // RTC_DCHECK_IS_ON
// Completing the operation before invoking the observer allows the observer
// to execute SetLocalDescription() without delay.
operation_complete_callback_();
observer_->OnSuccess(desc);
}
void OnFailure(RTCError error) override {
#if RTC_DCHECK_IS_ON
RTC_DCHECK(!was_called_);
was_called_ = true;
#endif // RTC_DCHECK_IS_ON
operation_complete_callback_();
observer_->OnFailure(std::move(error));
}
private:
#if RTC_DCHECK_IS_ON
bool was_called_ = false;
#endif // RTC_DCHECK_IS_ON
rtc::scoped_refptr<CreateSessionDescriptionObserver> observer_;
std::function<void()> operation_complete_callback_;
};
// Wrapper for SetSessionDescriptionObserver that invokes the success or failure
// callback in a posted message handled by the peer connection. This introduces
// a delay that prevents recursive API calls by the observer, but this also
// means that the PeerConnection can be modified before the observer sees the
// result of the operation. This is ill-advised for synchronizing states.
//
// Implements both the SetLocalDescriptionObserverInterface and the
// SetRemoteDescriptionObserverInterface.
class SdpOfferAnswerHandler::SetSessionDescriptionObserverAdapter
: public SetLocalDescriptionObserverInterface,
public SetRemoteDescriptionObserverInterface {
public:
SetSessionDescriptionObserverAdapter(
rtc::WeakPtr<SdpOfferAnswerHandler> handler,
rtc::scoped_refptr<SetSessionDescriptionObserver> inner_observer)
: handler_(std::move(handler)),
inner_observer_(std::move(inner_observer)) {}
// SetLocalDescriptionObserverInterface implementation.
void OnSetLocalDescriptionComplete(RTCError error) override {
OnSetDescriptionComplete(std::move(error));
}
// SetRemoteDescriptionObserverInterface implementation.
void OnSetRemoteDescriptionComplete(RTCError error) override {
OnSetDescriptionComplete(std::move(error));
}
private:
void OnSetDescriptionComplete(RTCError error) {
if (!handler_)
return;
if (error.ok()) {
handler_->pc_->message_handler()->PostSetSessionDescriptionSuccess(
inner_observer_.get());
} else {
handler_->pc_->message_handler()->PostSetSessionDescriptionFailure(
inner_observer_.get(), std::move(error));
}
}
rtc::WeakPtr<SdpOfferAnswerHandler> handler_;
rtc::scoped_refptr<SetSessionDescriptionObserver> inner_observer_;
};
class SdpOfferAnswerHandler::LocalIceCredentialsToReplace {
public:
// Sets the ICE credentials that need restarting to the ICE credentials of
// the current and pending descriptions.
void SetIceCredentialsFromLocalDescriptions(
const SessionDescriptionInterface* current_local_description,
const SessionDescriptionInterface* pending_local_description) {
ice_credentials_.clear();
if (current_local_description) {
AppendIceCredentialsFromSessionDescription(*current_local_description);
}
if (pending_local_description) {
AppendIceCredentialsFromSessionDescription(*pending_local_description);
}
}
void ClearIceCredentials() { ice_credentials_.clear(); }
// Returns true if we have ICE credentials that need restarting.
bool HasIceCredentials() const { return !ice_credentials_.empty(); }
// Returns true if `local_description` shares no ICE credentials with the
// ICE credentials that need restarting.
bool SatisfiesIceRestart(
const SessionDescriptionInterface& local_description) const {
for (const auto& transport_info :
local_description.description()->transport_infos()) {
if (ice_credentials_.find(std::make_pair(
transport_info.description.ice_ufrag,
transport_info.description.ice_pwd)) != ice_credentials_.end()) {
return false;
}
}
return true;
}
private:
void AppendIceCredentialsFromSessionDescription(
const SessionDescriptionInterface& desc) {
for (const auto& transport_info : desc.description()->transport_infos()) {
ice_credentials_.insert(
std::make_pair(transport_info.description.ice_ufrag,
transport_info.description.ice_pwd));
}
}
std::set<std::pair<std::string, std::string>> ice_credentials_;
};
SdpOfferAnswerHandler::SdpOfferAnswerHandler(PeerConnectionSdpMethods* pc,
ConnectionContext* context)
: pc_(pc),
context_(context),
local_streams_(StreamCollection::Create()),
remote_streams_(StreamCollection::Create()),
operations_chain_(rtc::OperationsChain::Create()),
rtcp_cname_(GenerateRtcpCname()),
local_ice_credentials_to_replace_(new LocalIceCredentialsToReplace()),
weak_ptr_factory_(this) {
operations_chain_->SetOnChainEmptyCallback(
[this_weak_ptr = weak_ptr_factory_.GetWeakPtr()]() {
if (!this_weak_ptr)
return;
this_weak_ptr->OnOperationsChainEmpty();
});
}
SdpOfferAnswerHandler::~SdpOfferAnswerHandler() {}
// Static
std::unique_ptr<SdpOfferAnswerHandler> SdpOfferAnswerHandler::Create(
PeerConnectionSdpMethods* pc,
const PeerConnectionInterface::RTCConfiguration& configuration,
PeerConnectionDependencies& dependencies,
ConnectionContext* context,
PayloadTypeSuggester* pt_suggester) {
auto handler = absl::WrapUnique(new SdpOfferAnswerHandler(pc, context));
handler->Initialize(configuration, dependencies, context, pt_suggester);
return handler;
}
void SdpOfferAnswerHandler::Initialize(
const PeerConnectionInterface::RTCConfiguration& configuration,
PeerConnectionDependencies& dependencies,
ConnectionContext* context,
PayloadTypeSuggester* pt_suggester) {
RTC_DCHECK_RUN_ON(signaling_thread());
// 100 kbps is used by default, but can be overriden by a non-standard
// RTCConfiguration value (not available on Web).
video_options_.screencast_min_bitrate_kbps =
configuration.screencast_min_bitrate.value_or(100);
audio_options_.audio_jitter_buffer_max_packets =
configuration.audio_jitter_buffer_max_packets;
audio_options_.audio_jitter_buffer_fast_accelerate =
configuration.audio_jitter_buffer_fast_accelerate;
audio_options_.audio_jitter_buffer_min_delay_ms =
configuration.audio_jitter_buffer_min_delay_ms;
// Obtain a certificate from RTCConfiguration if any were provided (optional).
rtc::scoped_refptr<rtc::RTCCertificate> certificate;
if (!configuration.certificates.empty()) {
// TODO(hbos,torbjorng): Decide on certificate-selection strategy instead of
// just picking the first one. The decision should be made based on the DTLS
// handshake. The DTLS negotiations need to know about all certificates.
certificate = configuration.certificates[0];
}
webrtc_session_desc_factory_ =
std::make_unique<WebRtcSessionDescriptionFactory>(
context, this, pc_->session_id(), pc_->dtls_enabled(),
std::move(dependencies.cert_generator), std::move(certificate),
[this](const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) {
RTC_DCHECK_RUN_ON(signaling_thread());
transport_controller_s()->SetLocalCertificate(certificate);
},
pt_suggester, pc_->trials());
if (pc_->options()->disable_encryption) {
RTC_LOG(LS_INFO)
<< "Disabling encryption. This should only be done in tests.";
webrtc_session_desc_factory_->SetInsecureForTesting();
}
webrtc_session_desc_factory_->set_enable_encrypted_rtp_header_extensions(
pc_->GetCryptoOptions().srtp.enable_encrypted_rtp_header_extensions);
webrtc_session_desc_factory_->set_is_unified_plan(IsUnifiedPlan());
if (dependencies.video_bitrate_allocator_factory) {
video_bitrate_allocator_factory_ =
std::move(dependencies.video_bitrate_allocator_factory);
} else {
video_bitrate_allocator_factory_ =
CreateBuiltinVideoBitrateAllocatorFactory();
}
}
// ==================================================================
// Access to pc_ variables
cricket::MediaEngineInterface* SdpOfferAnswerHandler::media_engine() const {
RTC_DCHECK(context_);
return context_->media_engine();
}
TransceiverList* SdpOfferAnswerHandler::transceivers() {
if (!pc_->rtp_manager()) {
return nullptr;
}
return pc_->rtp_manager()->transceivers();
}
const TransceiverList* SdpOfferAnswerHandler::transceivers() const {
if (!pc_->rtp_manager()) {
return nullptr;
}
return pc_->rtp_manager()->transceivers();
}
JsepTransportController* SdpOfferAnswerHandler::transport_controller_s() {
return pc_->transport_controller_s();
}
JsepTransportController* SdpOfferAnswerHandler::transport_controller_n() {
return pc_->transport_controller_n();
}
const JsepTransportController* SdpOfferAnswerHandler::transport_controller_s()
const {
return pc_->transport_controller_s();
}
const JsepTransportController* SdpOfferAnswerHandler::transport_controller_n()
const {
return pc_->transport_controller_n();
}
DataChannelController* SdpOfferAnswerHandler::data_channel_controller() {
return pc_->data_channel_controller();
}
const DataChannelController* SdpOfferAnswerHandler::data_channel_controller()
const {
return pc_->data_channel_controller();
}
cricket::PortAllocator* SdpOfferAnswerHandler::port_allocator() {
return pc_->port_allocator();
}
const cricket::PortAllocator* SdpOfferAnswerHandler::port_allocator() const {
return pc_->port_allocator();
}
RtpTransmissionManager* SdpOfferAnswerHandler::rtp_manager() {
return pc_->rtp_manager();
}
const RtpTransmissionManager* SdpOfferAnswerHandler::rtp_manager() const {
return pc_->rtp_manager();
}
// ===================================================================
void SdpOfferAnswerHandler::PrepareForShutdown() {
RTC_DCHECK_RUN_ON(signaling_thread());
weak_ptr_factory_.InvalidateWeakPtrs();
}
void SdpOfferAnswerHandler::Close() {
ChangeSignalingState(PeerConnectionInterface::kClosed);
}
void SdpOfferAnswerHandler::RestartIce() {
RTC_DCHECK_RUN_ON(signaling_thread());
local_ice_credentials_to_replace_->SetIceCredentialsFromLocalDescriptions(
current_local_description(), pending_local_description());
UpdateNegotiationNeeded();
}
rtc::Thread* SdpOfferAnswerHandler::signaling_thread() const {
return context_->signaling_thread();
}
rtc::Thread* SdpOfferAnswerHandler::network_thread() const {
return context_->network_thread();
}
void SdpOfferAnswerHandler::CreateOffer(
CreateSessionDescriptionObserver* observer,
const PeerConnectionInterface::RTCOfferAnswerOptions& options) {
RTC_DCHECK_RUN_ON(signaling_thread());
// Chain this operation. If asynchronous operations are pending on the chain,
// this operation will be queued to be invoked, otherwise the contents of the
// lambda will execute immediately.
operations_chain_->ChainOperation(
[this_weak_ptr = weak_ptr_factory_.GetWeakPtr(),
observer_refptr =
rtc::scoped_refptr<CreateSessionDescriptionObserver>(observer),
options](std::function<void()> operations_chain_callback) {
// Abort early if `this_weak_ptr` is no longer valid.
if (!this_weak_ptr) {
observer_refptr->OnFailure(
RTCError(RTCErrorType::INTERNAL_ERROR,
"CreateOffer failed because the session was shut down"));
operations_chain_callback();
return;
}
// The operation completes asynchronously when the wrapper is invoked.
auto observer_wrapper = rtc::make_ref_counted<
CreateSessionDescriptionObserverOperationWrapper>(
std::move(observer_refptr), std::move(operations_chain_callback));
this_weak_ptr->DoCreateOffer(options, observer_wrapper);
});
}
void SdpOfferAnswerHandler::SetLocalDescription(
SetSessionDescriptionObserver* observer,
SessionDescriptionInterface* desc_ptr) {
RTC_DCHECK_RUN_ON(signaling_thread());
// Chain this operation. If asynchronous operations are pending on the chain,
// this operation will be queued to be invoked, otherwise the contents of the
// lambda will execute immediately.
operations_chain_->ChainOperation(
[this_weak_ptr = weak_ptr_factory_.GetWeakPtr(),
observer_refptr =
rtc::scoped_refptr<SetSessionDescriptionObserver>(observer),
desc = std::unique_ptr<SessionDescriptionInterface>(desc_ptr)](
std::function<void()> operations_chain_callback) mutable {
// Abort early if `this_weak_ptr` is no longer valid.
if (!this_weak_ptr) {
// For consistency with SetSessionDescriptionObserverAdapter whose
// posted messages doesn't get processed when the PC is destroyed, we
// do not inform `observer_refptr` that the operation failed.
operations_chain_callback();
return;
}
// SetSessionDescriptionObserverAdapter takes care of making sure the
// `observer_refptr` is invoked in a posted message.
this_weak_ptr->DoSetLocalDescription(
std::move(desc),
rtc::make_ref_counted<SetSessionDescriptionObserverAdapter>(
this_weak_ptr, observer_refptr));
// For backwards-compatability reasons, we declare the operation as
// completed here (rather than in a post), so that the operation chain
// is not blocked by this operation when the observer is invoked. This
// allows the observer to trigger subsequent offer/answer operations
// synchronously if the operation chain is now empty.
operations_chain_callback();
});
}
void SdpOfferAnswerHandler::SetLocalDescription(
std::unique_ptr<SessionDescriptionInterface> desc,
rtc::scoped_refptr<SetLocalDescriptionObserverInterface> observer) {
RTC_DCHECK_RUN_ON(signaling_thread());
// Chain this operation. If asynchronous operations are pending on the chain,
// this operation will be queued to be invoked, otherwise the contents of the
// lambda will execute immediately.
operations_chain_->ChainOperation(
[this_weak_ptr = weak_ptr_factory_.GetWeakPtr(), observer,
desc = std::move(desc)](
std::function<void()> operations_chain_callback) mutable {
// Abort early if `this_weak_ptr` is no longer valid.
if (!this_weak_ptr) {
observer->OnSetLocalDescriptionComplete(RTCError(
RTCErrorType::INTERNAL_ERROR,
"SetLocalDescription failed because the session was shut down"));
operations_chain_callback();
return;
}
this_weak_ptr->DoSetLocalDescription(std::move(desc), observer);
// DoSetLocalDescription() is implemented as a synchronous operation.
// The `observer` will already have been informed that it completed, and
// we can mark this operation as complete without any loose ends.
operations_chain_callback();
});
}
void SdpOfferAnswerHandler::SetLocalDescription(
SetSessionDescriptionObserver* observer) {
RTC_DCHECK_RUN_ON(signaling_thread());
SetLocalDescription(
rtc::make_ref_counted<SetSessionDescriptionObserverAdapter>(
weak_ptr_factory_.GetWeakPtr(),
rtc::scoped_refptr<SetSessionDescriptionObserver>(observer)));
}
--> --------------------
--> maximum size reached
--> --------------------
