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/*
* Copyright 2018 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/jsep_transport.h"
#include <stddef.h>
#include <stdint.h>
#include <memory>
#include <type_traits>
#include <utility> // for std::pair
#include "api/array_view.h"
#include "api/candidate.h"
#include "p2p/base/p2p_constants.h"
#include "p2p/base/p2p_transport_channel.h"
#include "pc/sctp_data_channel_transport.h"
#include "rtc_base/checks.h"
#include "rtc_base/copy_on_write_buffer.h"
#include "rtc_base/logging.h"
#include "rtc_base/strings/string_builder.h"
using webrtc::SdpType;
namespace cricket {
JsepTransportDescription::JsepTransportDescription() {}
JsepTransportDescription::JsepTransportDescription(
bool rtcp_mux_enabled,
const std::vector<CryptoParams>& cryptos,
const std::vector<int>& encrypted_header_extension_ids,
int rtp_abs_sendtime_extn_id,
const TransportDescription& transport_desc)
: rtcp_mux_enabled(rtcp_mux_enabled),
cryptos(cryptos),
encrypted_header_extension_ids(encrypted_header_extension_ids),
rtp_abs_sendtime_extn_id(rtp_abs_sendtime_extn_id),
transport_desc(transport_desc) {}
JsepTransportDescription::JsepTransportDescription(
const JsepTransportDescription& from)
: rtcp_mux_enabled(from.rtcp_mux_enabled),
cryptos(from.cryptos),
encrypted_header_extension_ids(from.encrypted_header_extension_ids),
rtp_abs_sendtime_extn_id(from.rtp_abs_sendtime_extn_id),
transport_desc(from.transport_desc) {}
JsepTransportDescription::~JsepTransportDescription() = default;
JsepTransportDescription& JsepTransportDescription::operator=(
const JsepTransportDescription& from) {
if (this == &from) {
return *this;
}
rtcp_mux_enabled = from.rtcp_mux_enabled;
cryptos = from.cryptos;
encrypted_header_extension_ids = from.encrypted_header_extension_ids;
rtp_abs_sendtime_extn_id = from.rtp_abs_sendtime_extn_id;
transport_desc = from.transport_desc;
return *this;
}
JsepTransport::JsepTransport(
const std::string& mid,
const rtc::scoped_refptr<rtc::RTCCertificate>& local_certificate,
rtc::scoped_refptr<webrtc::IceTransportInterface> ice_transport,
rtc::scoped_refptr<webrtc::IceTransportInterface> rtcp_ice_transport,
std::unique_ptr<webrtc::RtpTransport> unencrypted_rtp_transport,
std::unique_ptr<webrtc::SrtpTransport> sdes_transport,
std::unique_ptr<webrtc::DtlsSrtpTransport> dtls_srtp_transport,
std::unique_ptr<webrtc::RtpTransportInternal> datagram_rtp_transport,
std::unique_ptr<DtlsTransportInternal> rtp_dtls_transport,
std::unique_ptr<DtlsTransportInternal> rtcp_dtls_transport,
std::unique_ptr<SctpTransportInternal> sctp_transport)
: network_thread_(rtc::Thread::Current()),
mid_(mid),
local_certificate_(local_certificate),
ice_transport_(std::move(ice_transport)),
rtcp_ice_transport_(std::move(rtcp_ice_transport)),
unencrypted_rtp_transport_(std::move(unencrypted_rtp_transport)),
sdes_transport_(std::move(sdes_transport)),
dtls_srtp_transport_(std::move(dtls_srtp_transport)),
rtp_dtls_transport_(
rtp_dtls_transport ? new rtc::RefCountedObject<webrtc::DtlsTransport>(
std::move(rtp_dtls_transport))
: nullptr),
rtcp_dtls_transport_(
rtcp_dtls_transport
? new rtc::RefCountedObject<webrtc::DtlsTransport>(
std::move(rtcp_dtls_transport))
: nullptr),
sctp_data_channel_transport_(
sctp_transport ? std::make_unique<webrtc::SctpDataChannelTransport>(
sctp_transport.get())
: nullptr),
sctp_transport_(sctp_transport
? new rtc::RefCountedObject<webrtc::SctpTransport>(
std::move(sctp_transport))
: nullptr) {
RTC_DCHECK(ice_transport_);
RTC_DCHECK(rtp_dtls_transport_);
// |rtcp_ice_transport_| must be present iff |rtcp_dtls_transport_| is
// present.
RTC_DCHECK_EQ((rtcp_ice_transport_ != nullptr),
(rtcp_dtls_transport_ != nullptr));
// Verify the "only one out of these three can be set" invariant.
if (unencrypted_rtp_transport_) {
RTC_DCHECK(!sdes_transport);
RTC_DCHECK(!dtls_srtp_transport);
} else if (sdes_transport_) {
RTC_DCHECK(!unencrypted_rtp_transport);
RTC_DCHECK(!dtls_srtp_transport);
} else {
RTC_DCHECK(dtls_srtp_transport_);
RTC_DCHECK(!unencrypted_rtp_transport);
RTC_DCHECK(!sdes_transport);
}
if (sctp_transport_) {
sctp_transport_->SetDtlsTransport(rtp_dtls_transport_);
}
if (datagram_rtp_transport_ && default_rtp_transport()) {
composite_rtp_transport_ = std::make_unique<webrtc::CompositeRtpTransport>(
std::vector<webrtc::RtpTransportInternal*>{
datagram_rtp_transport_.get(), default_rtp_transport()});
}
}
JsepTransport::~JsepTransport() {
if (sctp_transport_) {
sctp_transport_->Clear();
}
// Clear all DtlsTransports. There may be pointers to these from
// other places, so we can't assume they'll be deleted by the destructor.
rtp_dtls_transport_->Clear();
if (rtcp_dtls_transport_) {
rtcp_dtls_transport_->Clear();
}
// ICE will be the last transport to be deleted.
}
webrtc::RTCError JsepTransport::SetLocalJsepTransportDescription(
const JsepTransportDescription& jsep_description,
SdpType type) {
webrtc::RTCError error;
RTC_DCHECK_RUN_ON(network_thread_);
IceParameters ice_parameters =
jsep_description.transport_desc.GetIceParameters();
webrtc::RTCError ice_parameters_result = ice_parameters.Validate();
if (!ice_parameters_result.ok()) {
rtc::StringBuilder sb;
sb << "Invalid ICE parameters: " << ice_parameters_result.message();
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
sb.Release());
}
if (!SetRtcpMux(jsep_description.rtcp_mux_enabled, type,
ContentSource::CS_LOCAL)) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Failed to setup RTCP mux.");
}
// If doing SDES, setup the SDES crypto parameters.
{
rtc::CritScope scope(&accessor_lock_);
if (sdes_transport_) {
RTC_DCHECK(!unencrypted_rtp_transport_);
RTC_DCHECK(!dtls_srtp_transport_);
if (!SetSdes(jsep_description.cryptos,
jsep_description.encrypted_header_extension_ids, type,
ContentSource::CS_LOCAL)) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Failed to setup SDES crypto parameters.");
}
} else if (dtls_srtp_transport_) {
RTC_DCHECK(!unencrypted_rtp_transport_);
RTC_DCHECK(!sdes_transport_);
dtls_srtp_transport_->UpdateRecvEncryptedHeaderExtensionIds(
jsep_description.encrypted_header_extension_ids);
}
}
bool ice_restarting =
local_description_ != nullptr &&
IceCredentialsChanged(local_description_->transport_desc.ice_ufrag,
local_description_->transport_desc.ice_pwd,
ice_parameters.ufrag, ice_parameters.pwd);
local_description_.reset(new JsepTransportDescription(jsep_description));
rtc::SSLFingerprint* local_fp =
local_description_->transport_desc.identity_fingerprint.get();
if (!local_fp) {
local_certificate_ = nullptr;
} else {
error = VerifyCertificateFingerprint(local_certificate_, local_fp);
if (!error.ok()) {
local_description_.reset();
return error;
}
}
{
rtc::CritScope scope(&accessor_lock_);
RTC_DCHECK(rtp_dtls_transport_->internal());
rtp_dtls_transport_->internal()->ice_transport()->SetIceParameters(
ice_parameters);
if (rtcp_dtls_transport_) {
RTC_DCHECK(rtcp_dtls_transport_->internal());
rtcp_dtls_transport_->internal()->ice_transport()->SetIceParameters(
ice_parameters);
}
}
// If PRANSWER/ANSWER is set, we should decide transport protocol type.
if (type == SdpType::kPrAnswer || type == SdpType::kAnswer) {
error = NegotiateAndSetDtlsParameters(type);
}
if (!error.ok()) {
local_description_.reset();
return error;
}
{
rtc::CritScope scope(&accessor_lock_);
if (needs_ice_restart_ && ice_restarting) {
needs_ice_restart_ = false;
RTC_LOG(LS_VERBOSE) << "needs-ice-restart flag cleared for transport "
<< mid();
}
}
return webrtc::RTCError::OK();
}
webrtc::RTCError JsepTransport::SetRemoteJsepTransportDescription(
const JsepTransportDescription& jsep_description,
webrtc::SdpType type) {
webrtc::RTCError error;
RTC_DCHECK_RUN_ON(network_thread_);
IceParameters ice_parameters =
jsep_description.transport_desc.GetIceParameters();
webrtc::RTCError ice_parameters_result = ice_parameters.Validate();
if (!ice_parameters_result.ok()) {
remote_description_.reset();
rtc::StringBuilder sb;
sb << "Invalid ICE parameters: " << ice_parameters_result.message();
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
sb.Release());
}
if (!SetRtcpMux(jsep_description.rtcp_mux_enabled, type,
ContentSource::CS_REMOTE)) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Failed to setup RTCP mux.");
}
// If doing SDES, setup the SDES crypto parameters.
{
rtc::CritScope lock(&accessor_lock_);
if (sdes_transport_) {
RTC_DCHECK(!unencrypted_rtp_transport_);
RTC_DCHECK(!dtls_srtp_transport_);
if (!SetSdes(jsep_description.cryptos,
jsep_description.encrypted_header_extension_ids, type,
ContentSource::CS_REMOTE)) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Failed to setup SDES crypto parameters.");
}
sdes_transport_->CacheRtpAbsSendTimeHeaderExtension(
jsep_description.rtp_abs_sendtime_extn_id);
} else if (dtls_srtp_transport_) {
RTC_DCHECK(!unencrypted_rtp_transport_);
RTC_DCHECK(!sdes_transport_);
dtls_srtp_transport_->UpdateSendEncryptedHeaderExtensionIds(
jsep_description.encrypted_header_extension_ids);
dtls_srtp_transport_->CacheRtpAbsSendTimeHeaderExtension(
jsep_description.rtp_abs_sendtime_extn_id);
}
}
remote_description_.reset(new JsepTransportDescription(jsep_description));
RTC_DCHECK(rtp_dtls_transport());
SetRemoteIceParameters(ice_parameters, rtp_dtls_transport()->ice_transport());
if (rtcp_dtls_transport()) {
SetRemoteIceParameters(ice_parameters,
rtcp_dtls_transport()->ice_transport());
}
// If PRANSWER/ANSWER is set, we should decide transport protocol type.
if (type == SdpType::kPrAnswer || type == SdpType::kAnswer) {
error = NegotiateAndSetDtlsParameters(SdpType::kOffer);
}
if (!error.ok()) {
remote_description_.reset();
return error;
}
return webrtc::RTCError::OK();
}
webrtc::RTCError JsepTransport::AddRemoteCandidates(
const Candidates& candidates) {
RTC_DCHECK_RUN_ON(network_thread_);
if (!local_description_ || !remote_description_) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_STATE,
mid() +
" is not ready to use the remote candidate "
"because the local or remote description is "
"not set.");
}
for (const cricket::Candidate& candidate : candidates) {
auto transport =
candidate.component() == cricket::ICE_CANDIDATE_COMPONENT_RTP
? rtp_dtls_transport_
: rtcp_dtls_transport_;
if (!transport) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Candidate has an unknown component: " +
candidate.ToSensitiveString() + " for mid " +
mid());
}
RTC_DCHECK(transport->internal() && transport->internal()->ice_transport());
transport->internal()->ice_transport()->AddRemoteCandidate(candidate);
}
return webrtc::RTCError::OK();
}
void JsepTransport::SetNeedsIceRestartFlag() {
rtc::CritScope scope(&accessor_lock_);
if (!needs_ice_restart_) {
needs_ice_restart_ = true;
RTC_LOG(LS_VERBOSE) << "needs-ice-restart flag set for transport " << mid();
}
}
absl::optional<rtc::SSLRole> JsepTransport::GetDtlsRole() const {
RTC_DCHECK_RUN_ON(network_thread_);
rtc::CritScope scope(&accessor_lock_);
RTC_DCHECK(rtp_dtls_transport_);
RTC_DCHECK(rtp_dtls_transport_->internal());
rtc::SSLRole dtls_role;
if (!rtp_dtls_transport_->internal()->GetDtlsRole(&dtls_role)) {
return absl::optional<rtc::SSLRole>();
}
return absl::optional<rtc::SSLRole>(dtls_role);
}
bool JsepTransport::GetStats(TransportStats* stats) {
RTC_DCHECK_RUN_ON(network_thread_);
rtc::CritScope scope(&accessor_lock_);
stats->transport_name = mid();
stats->channel_stats.clear();
RTC_DCHECK(rtp_dtls_transport_->internal());
bool ret = GetTransportStats(rtp_dtls_transport_->internal(), stats);
if (rtcp_dtls_transport_) {
RTC_DCHECK(rtcp_dtls_transport_->internal());
ret &= GetTransportStats(rtcp_dtls_transport_->internal(), stats);
}
return ret;
}
webrtc::RTCError JsepTransport::VerifyCertificateFingerprint(
const rtc::RTCCertificate* certificate,
const rtc::SSLFingerprint* fingerprint) const {
RTC_DCHECK_RUN_ON(network_thread_);
if (!fingerprint) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"No fingerprint");
}
if (!certificate) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Fingerprint provided but no identity available.");
}
std::unique_ptr<rtc::SSLFingerprint> fp_tmp =
rtc::SSLFingerprint::CreateUnique(fingerprint->algorithm,
*certificate->identity());
RTC_DCHECK(fp_tmp.get() != NULL);
if (*fp_tmp == *fingerprint) {
return webrtc::RTCError::OK();
}
char ss_buf[1024];
rtc::SimpleStringBuilder desc(ss_buf);
desc << "Local fingerprint does not match identity. Expected: ";
desc << fp_tmp->ToString();
desc << " Got: " << fingerprint->ToString();
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
std::string(desc.str()));
}
void JsepTransport::SetActiveResetSrtpParams(bool active_reset_srtp_params) {
RTC_DCHECK_RUN_ON(network_thread_);
rtc::CritScope scope(&accessor_lock_);
if (dtls_srtp_transport_) {
RTC_LOG(INFO)
<< "Setting active_reset_srtp_params of DtlsSrtpTransport to: "
<< active_reset_srtp_params;
dtls_srtp_transport_->SetActiveResetSrtpParams(active_reset_srtp_params);
}
}
void JsepTransport::SetRemoteIceParameters(
const IceParameters& ice_parameters,
IceTransportInternal* ice_transport) {
RTC_DCHECK_RUN_ON(network_thread_);
RTC_DCHECK(ice_transport);
RTC_DCHECK(remote_description_);
ice_transport->SetRemoteIceParameters(ice_parameters);
ice_transport->SetRemoteIceMode(remote_description_->transport_desc.ice_mode);
}
webrtc::RTCError JsepTransport::SetNegotiatedDtlsParameters(
DtlsTransportInternal* dtls_transport,
absl::optional<rtc::SSLRole> dtls_role,
rtc::SSLFingerprint* remote_fingerprint) {
RTC_DCHECK(dtls_transport);
// Set SSL role. Role must be set before fingerprint is applied, which
// initiates DTLS setup.
if (dtls_role && !dtls_transport->SetDtlsRole(*dtls_role)) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Failed to set SSL role for the transport.");
}
// Apply remote fingerprint.
if (!remote_fingerprint ||
!dtls_transport->SetRemoteFingerprint(
remote_fingerprint->algorithm, remote_fingerprint->digest.cdata(),
remote_fingerprint->digest.size())) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_PARAMETER,
"Failed to apply remote fingerprint.");
}
return webrtc::RTCError::OK();
}
bool JsepTransport::SetRtcpMux(bool enable,
webrtc::SdpType type,
ContentSource source) {
RTC_DCHECK_RUN_ON(network_thread_);
bool ret = false;
switch (type) {
case SdpType::kOffer:
ret = rtcp_mux_negotiator_.SetOffer(enable, source);
break;
case SdpType::kPrAnswer:
// This may activate RTCP muxing, but we don't yet destroy the transport
// because the final answer may deactivate it.
ret = rtcp_mux_negotiator_.SetProvisionalAnswer(enable, source);
break;
case SdpType::kAnswer:
ret = rtcp_mux_negotiator_.SetAnswer(enable, source);
if (ret && rtcp_mux_negotiator_.IsActive()) {
ActivateRtcpMux();
}
break;
default:
RTC_NOTREACHED();
}
if (!ret) {
return false;
}
auto transport = rtp_transport();
transport->SetRtcpMuxEnabled(rtcp_mux_negotiator_.IsActive());
return ret;
}
void JsepTransport::ActivateRtcpMux() {
{
// Don't hold the network_thread_ lock while calling other functions,
// since they might call other functions that call RTC_DCHECK_RUN_ON.
// TODO(https://crbug.com/webrtc/10318): Simplify when possible.
RTC_DCHECK_RUN_ON(network_thread_);
}
{
rtc::CritScope scope(&accessor_lock_);
if (unencrypted_rtp_transport_) {
RTC_DCHECK(!sdes_transport_);
RTC_DCHECK(!dtls_srtp_transport_);
unencrypted_rtp_transport_->SetRtcpPacketTransport(nullptr);
} else if (sdes_transport_) {
RTC_DCHECK(!unencrypted_rtp_transport_);
RTC_DCHECK(!dtls_srtp_transport_);
sdes_transport_->SetRtcpPacketTransport(nullptr);
} else if (dtls_srtp_transport_) {
RTC_DCHECK(dtls_srtp_transport_);
RTC_DCHECK(!unencrypted_rtp_transport_);
RTC_DCHECK(!sdes_transport_);
dtls_srtp_transport_->SetDtlsTransports(rtp_dtls_transport_locked(),
/*rtcp_dtls_transport=*/nullptr);
}
rtcp_dtls_transport_ = nullptr; // Destroy this reference.
}
// Notify the JsepTransportController to update the aggregate states.
SignalRtcpMuxActive();
}
bool JsepTransport::SetSdes(const std::vector<CryptoParams>& cryptos,
const std::vector<int>& encrypted_extension_ids,
webrtc::SdpType type,
ContentSource source) {
RTC_DCHECK_RUN_ON(network_thread_);
bool ret = false;
ret = sdes_negotiator_.Process(cryptos, type, source);
if (!ret) {
return ret;
}
if (source == ContentSource::CS_LOCAL) {
recv_extension_ids_ = encrypted_extension_ids;
} else {
send_extension_ids_ = encrypted_extension_ids;
}
// If setting an SDES answer succeeded, apply the negotiated parameters
// to the SRTP transport.
if ((type == SdpType::kPrAnswer || type == SdpType::kAnswer) && ret) {
if (sdes_negotiator_.send_cipher_suite() &&
sdes_negotiator_.recv_cipher_suite()) {
RTC_DCHECK(send_extension_ids_);
RTC_DCHECK(recv_extension_ids_);
ret = sdes_transport_->SetRtpParams(
*(sdes_negotiator_.send_cipher_suite()),
sdes_negotiator_.send_key().data(),
static_cast<int>(sdes_negotiator_.send_key().size()),
*(send_extension_ids_), *(sdes_negotiator_.recv_cipher_suite()),
sdes_negotiator_.recv_key().data(),
static_cast<int>(sdes_negotiator_.recv_key().size()),
*(recv_extension_ids_));
} else {
RTC_LOG(LS_INFO) << "No crypto keys are provided for SDES.";
if (type == SdpType::kAnswer) {
// Explicitly reset the |sdes_transport_| if no crypto param is
// provided in the answer. No need to call |ResetParams()| for
// |sdes_negotiator_| because it resets the params inside |SetAnswer|.
sdes_transport_->ResetParams();
}
}
}
return ret;
}
webrtc::RTCError JsepTransport::NegotiateAndSetDtlsParameters(
SdpType local_description_type) {
RTC_DCHECK_RUN_ON(network_thread_);
if (!local_description_ || !remote_description_) {
return webrtc::RTCError(webrtc::RTCErrorType::INVALID_STATE,
"Applying an answer transport description "
"without applying any offer.");
}
std::unique_ptr<rtc::SSLFingerprint> remote_fingerprint;
absl::optional<rtc::SSLRole> negotiated_dtls_role;
rtc::SSLFingerprint* local_fp =
local_description_->transport_desc.identity_fingerprint.get();
rtc::SSLFingerprint* remote_fp =
remote_description_->transport_desc.identity_fingerprint.get();
if (remote_fp && local_fp) {
remote_fingerprint = std::make_unique<rtc::SSLFingerprint>(*remote_fp);
webrtc::RTCError error =
NegotiateDtlsRole(local_description_type,
local_description_->transport_desc.connection_role,
remote_description_->transport_desc.connection_role,
&negotiated_dtls_role);
if (!error.ok()) {
return error;
}
} else if (local_fp && (local_description_type == SdpType::kAnswer)) {
return webrtc::RTCError(
webrtc::RTCErrorType::INVALID_PARAMETER,
"Local fingerprint supplied when caller didn't offer DTLS.");
} else {
// We are not doing DTLS
remote_fingerprint = std::make_unique<rtc::SSLFingerprint>(
"", rtc::ArrayView<const uint8_t>());
}
// Now that we have negotiated everything, push it downward.
// Note that we cache the result so that if we have race conditions
// between future SetRemote/SetLocal invocations and new transport
// creation, we have the negotiation state saved until a new
// negotiation happens.
RTC_DCHECK(rtp_dtls_transport());
webrtc::RTCError error = SetNegotiatedDtlsParameters(
rtp_dtls_transport(), negotiated_dtls_role, remote_fingerprint.get());
if (!error.ok()) {
return error;
}
if (rtcp_dtls_transport()) {
error = SetNegotiatedDtlsParameters(
rtcp_dtls_transport(), negotiated_dtls_role, remote_fingerprint.get());
}
return error;
}
webrtc::RTCError JsepTransport::NegotiateDtlsRole(
SdpType local_description_type,
ConnectionRole local_connection_role,
ConnectionRole remote_connection_role,
absl::optional<rtc::SSLRole>* negotiated_dtls_role) {
// From RFC 4145, section-4.1, The following are the values that the
// 'setup' attribute can take in an offer/answer exchange:
// Offer Answer
// ________________
// active passive / holdconn
// passive active / holdconn
// actpass active / passive / holdconn
// holdconn holdconn
//
// Set the role that is most conformant with RFC 5763, Section 5, bullet 1
// The endpoint MUST use the setup attribute defined in [RFC4145].
// The endpoint that is the offerer MUST use the setup attribute
// value of setup:actpass and be prepared to receive a client_hello
// before it receives the answer. The answerer MUST use either a
// setup attribute value of setup:active or setup:passive. Note that
// if the answerer uses setup:passive, then the DTLS handshake will
// not begin until the answerer is received, which adds additional
// latency. setup:active allows the answer and the DTLS handshake to
// occur in parallel. Thus, setup:active is RECOMMENDED. Whichever
// party is active MUST initiate a DTLS handshake by sending a
// ClientHello over each flow (host/port quartet).
// IOW - actpass and passive modes should be treated as server and
// active as client.
bool is_remote_server = false;
if (local_description_type == SdpType::kOffer) {
if (local_connection_role != CONNECTIONROLE_ACTPASS) {
return webrtc::RTCError(
webrtc::RTCErrorType::INVALID_PARAMETER,
"Offerer must use actpass value for setup attribute.");
}
if (remote_connection_role == CONNECTIONROLE_ACTIVE ||
remote_connection_role == CONNECTIONROLE_PASSIVE ||
remote_connection_role == CONNECTIONROLE_NONE) {
is_remote_server = (remote_connection_role == CONNECTIONROLE_PASSIVE);
} else {
return webrtc::RTCError(
webrtc::RTCErrorType::INVALID_PARAMETER,
"Answerer must use either active or passive value "
"for setup attribute.");
}
// If remote is NONE or ACTIVE it will act as client.
} else {
if (remote_connection_role != CONNECTIONROLE_ACTPASS &&
remote_connection_role != CONNECTIONROLE_NONE) {
// Accept a remote role attribute that's not "actpass", but matches the
// current negotiated role. This is allowed by dtls-sdp, though our
// implementation will never generate such an offer as it's not
// recommended.
//
// See https://datatracker.ietf.org/doc/html/draft-ietf-mmusic-dtls-sdp,
// section 5.5.
auto current_dtls_role = GetDtlsRole();
if (!current_dtls_role ||
(*current_dtls_role == rtc::SSL_CLIENT &&
remote_connection_role == CONNECTIONROLE_ACTIVE) ||
(*current_dtls_role == rtc::SSL_SERVER &&
remote_connection_role == CONNECTIONROLE_PASSIVE)) {
return webrtc::RTCError(
webrtc::RTCErrorType::INVALID_PARAMETER,
"Offerer must use actpass value or current negotiated role for "
"setup attribute.");
}
}
if (local_connection_role == CONNECTIONROLE_ACTIVE ||
local_connection_role == CONNECTIONROLE_PASSIVE) {
is_remote_server = (local_connection_role == CONNECTIONROLE_ACTIVE);
} else {
return webrtc::RTCError(
webrtc::RTCErrorType::INVALID_PARAMETER,
"Answerer must use either active or passive value "
"for setup attribute.");
}
// If local is passive, local will act as server.
}
*negotiated_dtls_role =
(is_remote_server ? rtc::SSL_CLIENT : rtc::SSL_SERVER);
return webrtc::RTCError::OK();
}
bool JsepTransport::GetTransportStats(DtlsTransportInternal* dtls_transport,
TransportStats* stats) {
RTC_DCHECK_RUN_ON(network_thread_);
RTC_DCHECK(dtls_transport);
TransportChannelStats substats;
if (rtcp_dtls_transport_) {
substats.component = dtls_transport == rtcp_dtls_transport_->internal()
? ICE_CANDIDATE_COMPONENT_RTCP
: ICE_CANDIDATE_COMPONENT_RTP;
} else {
substats.component = ICE_CANDIDATE_COMPONENT_RTP;
}
dtls_transport->GetSslVersionBytes(&substats.ssl_version_bytes);
dtls_transport->GetSrtpCryptoSuite(&substats.srtp_crypto_suite);
dtls_transport->GetSslCipherSuite(&substats.ssl_cipher_suite);
substats.dtls_state = dtls_transport->dtls_state();
if (!dtls_transport->ice_transport()->GetStats(
&substats.ice_transport_stats)) {
return false;
}
stats->channel_stats.push_back(substats);
return true;
}
} // namespace cricket