7d0a77eef4
Our DTLS implementation doesn't do this, but other implementations may; see https://tools.ietf.org/html/rfc6347#section-4.1.1. BUG=chromium:537189 Review-Url: https://codereview.webrtc.org/2970883005 Cr-Commit-Position: refs/heads/master@{#18934}
688 lines
23 KiB
C++
688 lines
23 KiB
C++
/*
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* Copyright 2011 The WebRTC Project Authors. All rights reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include <memory>
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#include <utility>
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#include "webrtc/p2p/base/dtlstransportchannel.h"
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#include "webrtc/p2p/base/common.h"
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#include "webrtc/p2p/base/packettransportinternal.h"
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#include "webrtc/rtc_base/buffer.h"
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#include "webrtc/rtc_base/checks.h"
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#include "webrtc/rtc_base/dscp.h"
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#include "webrtc/rtc_base/messagequeue.h"
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#include "webrtc/rtc_base/sslstreamadapter.h"
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#include "webrtc/rtc_base/stream.h"
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#include "webrtc/rtc_base/thread.h"
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namespace cricket {
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// We don't pull the RTP constants from rtputils.h, to avoid a layer violation.
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static const size_t kDtlsRecordHeaderLen = 13;
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static const size_t kMaxDtlsPacketLen = 2048;
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static const size_t kMinRtpPacketLen = 12;
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// Maximum number of pending packets in the queue. Packets are read immediately
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// after they have been written, so a capacity of "1" is sufficient.
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static const size_t kMaxPendingPackets = 1;
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// Minimum and maximum values for the initial DTLS handshake timeout. We'll pick
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// an initial timeout based on ICE RTT estimates, but clamp it to this range.
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static const int kMinHandshakeTimeout = 50;
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static const int kMaxHandshakeTimeout = 3000;
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static bool IsDtlsPacket(const char* data, size_t len) {
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const uint8_t* u = reinterpret_cast<const uint8_t*>(data);
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return (len >= kDtlsRecordHeaderLen && (u[0] > 19 && u[0] < 64));
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}
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static bool IsDtlsClientHelloPacket(const char* data, size_t len) {
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if (!IsDtlsPacket(data, len)) {
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return false;
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}
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const uint8_t* u = reinterpret_cast<const uint8_t*>(data);
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return len > 17 && u[0] == 22 && u[13] == 1;
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}
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static bool IsRtpPacket(const char* data, size_t len) {
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const uint8_t* u = reinterpret_cast<const uint8_t*>(data);
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return (len >= kMinRtpPacketLen && (u[0] & 0xC0) == 0x80);
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}
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StreamInterfaceChannel::StreamInterfaceChannel(
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IceTransportInternal* ice_transport)
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: ice_transport_(ice_transport),
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state_(rtc::SS_OPEN),
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packets_(kMaxPendingPackets, kMaxDtlsPacketLen) {}
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rtc::StreamResult StreamInterfaceChannel::Read(void* buffer,
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size_t buffer_len,
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size_t* read,
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int* error) {
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if (state_ == rtc::SS_CLOSED)
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return rtc::SR_EOS;
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if (state_ == rtc::SS_OPENING)
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return rtc::SR_BLOCK;
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if (!packets_.ReadFront(buffer, buffer_len, read)) {
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return rtc::SR_BLOCK;
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}
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return rtc::SR_SUCCESS;
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}
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rtc::StreamResult StreamInterfaceChannel::Write(const void* data,
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size_t data_len,
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size_t* written,
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int* error) {
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// Always succeeds, since this is an unreliable transport anyway.
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// TODO(zhihuang): Should this block if ice_transport_'s temporarily
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// unwritable?
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rtc::PacketOptions packet_options;
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ice_transport_->SendPacket(static_cast<const char*>(data), data_len,
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packet_options);
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if (written) {
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*written = data_len;
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}
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return rtc::SR_SUCCESS;
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}
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bool StreamInterfaceChannel::OnPacketReceived(const char* data, size_t size) {
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// We force a read event here to ensure that we don't overflow our queue.
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bool ret = packets_.WriteBack(data, size, NULL);
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RTC_CHECK(ret) << "Failed to write packet to queue.";
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if (ret) {
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SignalEvent(this, rtc::SE_READ, 0);
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}
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return ret;
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}
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void StreamInterfaceChannel::Close() {
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packets_.Clear();
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state_ = rtc::SS_CLOSED;
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}
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DtlsTransport::DtlsTransport(IceTransportInternal* ice_transport,
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const rtc::CryptoOptions& crypto_options)
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: transport_name_(ice_transport->transport_name()),
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component_(ice_transport->component()),
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network_thread_(rtc::Thread::Current()),
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ice_transport_(ice_transport),
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downward_(NULL),
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srtp_ciphers_(GetSupportedDtlsSrtpCryptoSuites(crypto_options)),
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ssl_role_(rtc::SSL_CLIENT),
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ssl_max_version_(rtc::SSL_PROTOCOL_DTLS_12),
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crypto_options_(crypto_options) {
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ice_transport_->SignalWritableState.connect(this,
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&DtlsTransport::OnWritableState);
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ice_transport_->SignalReadPacket.connect(this, &DtlsTransport::OnReadPacket);
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ice_transport_->SignalSentPacket.connect(this, &DtlsTransport::OnSentPacket);
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ice_transport_->SignalReadyToSend.connect(this,
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&DtlsTransport::OnReadyToSend);
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ice_transport_->SignalReceivingState.connect(
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this, &DtlsTransport::OnReceivingState);
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}
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DtlsTransport::~DtlsTransport() {}
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bool DtlsTransport::SetLocalCertificate(
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const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) {
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if (dtls_active_) {
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if (certificate == local_certificate_) {
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// This may happen during renegotiation.
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LOG_J(LS_INFO, this) << "Ignoring identical DTLS identity";
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return true;
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} else {
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LOG_J(LS_ERROR, this) << "Can't change DTLS local identity in this state";
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return false;
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}
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}
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if (certificate) {
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local_certificate_ = certificate;
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dtls_active_ = true;
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} else {
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LOG_J(LS_INFO, this) << "NULL DTLS identity supplied. Not doing DTLS";
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}
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return true;
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}
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rtc::scoped_refptr<rtc::RTCCertificate> DtlsTransport::GetLocalCertificate()
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const {
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return local_certificate_;
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}
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bool DtlsTransport::SetSslMaxProtocolVersion(rtc::SSLProtocolVersion version) {
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if (dtls_active_) {
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LOG(LS_ERROR) << "Not changing max. protocol version "
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<< "while DTLS is negotiating";
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return false;
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}
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ssl_max_version_ = version;
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return true;
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}
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bool DtlsTransport::SetSslRole(rtc::SSLRole role) {
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if (dtls_) {
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if (ssl_role_ != role) {
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LOG(LS_ERROR) << "SSL Role can't be reversed after the session is setup.";
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return false;
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}
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return true;
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}
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ssl_role_ = role;
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return true;
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}
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bool DtlsTransport::GetSslRole(rtc::SSLRole* role) const {
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*role = ssl_role_;
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return true;
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}
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bool DtlsTransport::GetSslCipherSuite(int* cipher) {
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if (dtls_state() != DTLS_TRANSPORT_CONNECTED) {
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return false;
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}
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return dtls_->GetSslCipherSuite(cipher);
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}
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bool DtlsTransport::SetRemoteFingerprint(const std::string& digest_alg,
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const uint8_t* digest,
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size_t digest_len) {
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rtc::Buffer remote_fingerprint_value(digest, digest_len);
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// Once we have the local certificate, the same remote fingerprint can be set
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// multiple times.
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if (dtls_active_ && remote_fingerprint_value_ == remote_fingerprint_value &&
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!digest_alg.empty()) {
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// This may happen during renegotiation.
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LOG_J(LS_INFO, this) << "Ignoring identical remote DTLS fingerprint";
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return true;
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}
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// If the other side doesn't support DTLS, turn off |dtls_active_|.
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if (digest_alg.empty()) {
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RTC_DCHECK(!digest_len);
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LOG_J(LS_INFO, this) << "Other side didn't support DTLS.";
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dtls_active_ = false;
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return true;
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}
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// Otherwise, we must have a local certificate before setting remote
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// fingerprint.
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if (!dtls_active_) {
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LOG_J(LS_ERROR, this) << "Can't set DTLS remote settings in this state.";
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return false;
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}
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// At this point we know we are doing DTLS
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bool fingerprint_changing = remote_fingerprint_value_.size() > 0u;
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remote_fingerprint_value_ = std::move(remote_fingerprint_value);
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remote_fingerprint_algorithm_ = digest_alg;
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if (dtls_ && !fingerprint_changing) {
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// This can occur if DTLS is set up before a remote fingerprint is
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// received. For instance, if we set up DTLS due to receiving an early
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// ClientHello.
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rtc::SSLPeerCertificateDigestError err;
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if (!dtls_->SetPeerCertificateDigest(
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remote_fingerprint_algorithm_,
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reinterpret_cast<unsigned char*>(remote_fingerprint_value_.data()),
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remote_fingerprint_value_.size(), &err)) {
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LOG_J(LS_ERROR, this) << "Couldn't set DTLS certificate digest.";
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set_dtls_state(DTLS_TRANSPORT_FAILED);
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// If the error is "verification failed", don't return false, because
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// this means the fingerprint was formatted correctly but didn't match
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// the certificate from the DTLS handshake. Thus the DTLS state should go
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// to "failed", but SetRemoteDescription shouldn't fail.
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return err == rtc::SSLPeerCertificateDigestError::VERIFICATION_FAILED;
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}
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return true;
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}
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// If the fingerprint is changing, we'll tear down the DTLS association and
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// create a new one, resetting our state.
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if (dtls_ && fingerprint_changing) {
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dtls_.reset(nullptr);
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set_dtls_state(DTLS_TRANSPORT_NEW);
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set_writable(false);
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}
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if (!SetupDtls()) {
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set_dtls_state(DTLS_TRANSPORT_FAILED);
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return false;
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}
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return true;
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}
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std::unique_ptr<rtc::SSLCertificate> DtlsTransport::GetRemoteSSLCertificate()
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const {
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if (!dtls_) {
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return nullptr;
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}
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return dtls_->GetPeerCertificate();
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}
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bool DtlsTransport::SetupDtls() {
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StreamInterfaceChannel* downward = new StreamInterfaceChannel(ice_transport_);
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dtls_.reset(rtc::SSLStreamAdapter::Create(downward));
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if (!dtls_) {
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LOG_J(LS_ERROR, this) << "Failed to create DTLS adapter.";
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delete downward;
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return false;
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}
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downward_ = downward;
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dtls_->SetIdentity(local_certificate_->identity()->GetReference());
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dtls_->SetMode(rtc::SSL_MODE_DTLS);
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dtls_->SetMaxProtocolVersion(ssl_max_version_);
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dtls_->SetServerRole(ssl_role_);
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dtls_->SignalEvent.connect(this, &DtlsTransport::OnDtlsEvent);
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dtls_->SignalSSLHandshakeError.connect(this,
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&DtlsTransport::OnDtlsHandshakeError);
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if (remote_fingerprint_value_.size() &&
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!dtls_->SetPeerCertificateDigest(
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remote_fingerprint_algorithm_,
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reinterpret_cast<unsigned char*>(remote_fingerprint_value_.data()),
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remote_fingerprint_value_.size())) {
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LOG_J(LS_ERROR, this) << "Couldn't set DTLS certificate digest.";
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return false;
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}
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// Set up DTLS-SRTP, if it's been enabled.
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if (!srtp_ciphers_.empty()) {
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if (!dtls_->SetDtlsSrtpCryptoSuites(srtp_ciphers_)) {
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LOG_J(LS_ERROR, this) << "Couldn't set DTLS-SRTP ciphers.";
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return false;
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}
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} else {
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LOG_J(LS_INFO, this) << "Not using DTLS-SRTP.";
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}
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LOG_J(LS_INFO, this) << "DTLS setup complete.";
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// If the underlying ice_transport is already writable at this point, we may
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// be able to start DTLS right away.
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MaybeStartDtls();
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return true;
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}
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bool DtlsTransport::GetSrtpCryptoSuite(int* cipher) {
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if (dtls_state() != DTLS_TRANSPORT_CONNECTED) {
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return false;
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}
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return dtls_->GetDtlsSrtpCryptoSuite(cipher);
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}
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// Called from upper layers to send a media packet.
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int DtlsTransport::SendPacket(const char* data,
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size_t size,
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const rtc::PacketOptions& options,
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int flags) {
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if (!dtls_active_) {
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// Not doing DTLS.
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return ice_transport_->SendPacket(data, size, options);
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}
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switch (dtls_state()) {
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case DTLS_TRANSPORT_NEW:
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// Can't send data until the connection is active.
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// TODO(ekr@rtfm.com): assert here if dtls_ is NULL?
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return -1;
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case DTLS_TRANSPORT_CONNECTING:
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// Can't send data until the connection is active.
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return -1;
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case DTLS_TRANSPORT_CONNECTED:
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if (flags & PF_SRTP_BYPASS) {
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RTC_DCHECK(!srtp_ciphers_.empty());
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if (!IsRtpPacket(data, size)) {
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return -1;
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}
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return ice_transport_->SendPacket(data, size, options);
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} else {
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return (dtls_->WriteAll(data, size, NULL, NULL) == rtc::SR_SUCCESS)
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? static_cast<int>(size)
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: -1;
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}
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case DTLS_TRANSPORT_FAILED:
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case DTLS_TRANSPORT_CLOSED:
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// Can't send anything when we're closed.
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return -1;
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default:
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RTC_NOTREACHED();
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return -1;
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}
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}
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bool DtlsTransport::IsDtlsConnected() {
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return dtls_ && dtls_->IsTlsConnected();
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}
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// The state transition logic here is as follows:
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// (1) If we're not doing DTLS-SRTP, then the state is just the
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// state of the underlying impl()
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// (2) If we're doing DTLS-SRTP:
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// - Prior to the DTLS handshake, the state is neither receiving nor
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// writable
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// - When the impl goes writable for the first time we
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// start the DTLS handshake
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// - Once the DTLS handshake completes, the state is that of the
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// impl again
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void DtlsTransport::OnWritableState(rtc::PacketTransportInternal* transport) {
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RTC_DCHECK(rtc::Thread::Current() == network_thread_);
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RTC_DCHECK(transport == ice_transport_);
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LOG_J(LS_VERBOSE, this)
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<< "DTLSTransportChannelWrapper: ice_transport writable state changed to "
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<< ice_transport_->writable();
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if (!dtls_active_) {
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// Not doing DTLS.
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// Note: SignalWritableState fired by set_writable.
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set_writable(ice_transport_->writable());
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return;
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}
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switch (dtls_state()) {
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case DTLS_TRANSPORT_NEW:
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MaybeStartDtls();
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break;
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case DTLS_TRANSPORT_CONNECTED:
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// Note: SignalWritableState fired by set_writable.
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set_writable(ice_transport_->writable());
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break;
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case DTLS_TRANSPORT_CONNECTING:
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// Do nothing.
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break;
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case DTLS_TRANSPORT_FAILED:
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case DTLS_TRANSPORT_CLOSED:
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// Should not happen. Do nothing.
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break;
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}
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}
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void DtlsTransport::OnReceivingState(rtc::PacketTransportInternal* transport) {
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RTC_DCHECK(rtc::Thread::Current() == network_thread_);
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RTC_DCHECK(transport == ice_transport_);
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LOG_J(LS_VERBOSE, this) << "DTLSTransportChannelWrapper: ice_transport "
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"receiving state changed to "
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<< ice_transport_->receiving();
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if (!dtls_active_ || dtls_state() == DTLS_TRANSPORT_CONNECTED) {
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// Note: SignalReceivingState fired by set_receiving.
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set_receiving(ice_transport_->receiving());
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}
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}
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void DtlsTransport::OnReadPacket(rtc::PacketTransportInternal* transport,
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const char* data,
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size_t size,
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const rtc::PacketTime& packet_time,
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int flags) {
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RTC_DCHECK(rtc::Thread::Current() == network_thread_);
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RTC_DCHECK(transport == ice_transport_);
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RTC_DCHECK(flags == 0);
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if (!dtls_active_) {
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// Not doing DTLS.
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SignalReadPacket(this, data, size, packet_time, 0);
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return;
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}
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switch (dtls_state()) {
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case DTLS_TRANSPORT_NEW:
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if (dtls_) {
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LOG_J(LS_INFO, this) << "Packet received before DTLS started.";
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} else {
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LOG_J(LS_WARNING, this) << "Packet received before we know if we are "
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<< "doing DTLS or not.";
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}
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// Cache a client hello packet received before DTLS has actually started.
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if (IsDtlsClientHelloPacket(data, size)) {
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LOG_J(LS_INFO, this) << "Caching DTLS ClientHello packet until DTLS is "
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<< "started.";
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cached_client_hello_.SetData(data, size);
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// If we haven't started setting up DTLS yet (because we don't have a
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// remote fingerprint/role), we can use the client hello as a clue that
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// the peer has chosen the client role, and proceed with the handshake.
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// The fingerprint will be verified when it's set.
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if (!dtls_ && local_certificate_) {
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SetSslRole(rtc::SSL_SERVER);
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SetupDtls();
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}
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} else {
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LOG_J(LS_INFO, this) << "Not a DTLS ClientHello packet; dropping.";
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}
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break;
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case DTLS_TRANSPORT_CONNECTING:
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case DTLS_TRANSPORT_CONNECTED:
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// We should only get DTLS or SRTP packets; STUN's already been demuxed.
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// Is this potentially a DTLS packet?
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if (IsDtlsPacket(data, size)) {
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if (!HandleDtlsPacket(data, size)) {
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LOG_J(LS_ERROR, this) << "Failed to handle DTLS packet.";
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return;
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}
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} else {
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// Not a DTLS packet; our handshake should be complete by now.
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if (dtls_state() != DTLS_TRANSPORT_CONNECTED) {
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LOG_J(LS_ERROR, this) << "Received non-DTLS packet before DTLS "
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<< "complete.";
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return;
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}
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// And it had better be a SRTP packet.
|
|
if (!IsRtpPacket(data, size)) {
|
|
LOG_J(LS_ERROR, this) << "Received unexpected non-DTLS packet.";
|
|
return;
|
|
}
|
|
|
|
// Sanity check.
|
|
RTC_DCHECK(!srtp_ciphers_.empty());
|
|
|
|
// Signal this upwards as a bypass packet.
|
|
SignalReadPacket(this, data, size, packet_time, PF_SRTP_BYPASS);
|
|
}
|
|
break;
|
|
case DTLS_TRANSPORT_FAILED:
|
|
case DTLS_TRANSPORT_CLOSED:
|
|
// This shouldn't be happening. Drop the packet.
|
|
break;
|
|
}
|
|
}
|
|
|
|
void DtlsTransport::OnSentPacket(rtc::PacketTransportInternal* transport,
|
|
const rtc::SentPacket& sent_packet) {
|
|
RTC_DCHECK(rtc::Thread::Current() == network_thread_);
|
|
|
|
SignalSentPacket(this, sent_packet);
|
|
}
|
|
|
|
void DtlsTransport::OnReadyToSend(rtc::PacketTransportInternal* transport) {
|
|
if (writable()) {
|
|
SignalReadyToSend(this);
|
|
}
|
|
}
|
|
|
|
void DtlsTransport::OnDtlsEvent(rtc::StreamInterface* dtls, int sig, int err) {
|
|
RTC_DCHECK(rtc::Thread::Current() == network_thread_);
|
|
RTC_DCHECK(dtls == dtls_.get());
|
|
if (sig & rtc::SE_OPEN) {
|
|
// This is the first time.
|
|
LOG_J(LS_INFO, this) << "DTLS handshake complete.";
|
|
if (dtls_->GetState() == rtc::SS_OPEN) {
|
|
// The check for OPEN shouldn't be necessary but let's make
|
|
// sure we don't accidentally frob the state if it's closed.
|
|
set_dtls_state(DTLS_TRANSPORT_CONNECTED);
|
|
set_writable(true);
|
|
}
|
|
}
|
|
if (sig & rtc::SE_READ) {
|
|
char buf[kMaxDtlsPacketLen];
|
|
size_t read;
|
|
int read_error;
|
|
rtc::StreamResult ret;
|
|
// The underlying DTLS stream may have received multiple DTLS records in
|
|
// one packet, so read all of them.
|
|
do {
|
|
ret = dtls_->Read(buf, sizeof(buf), &read, &read_error);
|
|
if (ret == rtc::SR_SUCCESS) {
|
|
SignalReadPacket(this, buf, read, rtc::CreatePacketTime(0), 0);
|
|
} else if (ret == rtc::SR_EOS) {
|
|
// Remote peer shut down the association with no error.
|
|
LOG_J(LS_INFO, this) << "DTLS transport closed";
|
|
set_writable(false);
|
|
set_dtls_state(DTLS_TRANSPORT_CLOSED);
|
|
} else if (ret == rtc::SR_ERROR) {
|
|
// Remote peer shut down the association with an error.
|
|
LOG_J(LS_INFO, this) << "DTLS transport error, code=" << read_error;
|
|
set_writable(false);
|
|
set_dtls_state(DTLS_TRANSPORT_FAILED);
|
|
}
|
|
} while (ret == rtc::SR_SUCCESS);
|
|
}
|
|
if (sig & rtc::SE_CLOSE) {
|
|
RTC_DCHECK(sig == rtc::SE_CLOSE); // SE_CLOSE should be by itself.
|
|
set_writable(false);
|
|
if (!err) {
|
|
LOG_J(LS_INFO, this) << "DTLS transport closed";
|
|
set_dtls_state(DTLS_TRANSPORT_CLOSED);
|
|
} else {
|
|
LOG_J(LS_INFO, this) << "DTLS transport error, code=" << err;
|
|
set_dtls_state(DTLS_TRANSPORT_FAILED);
|
|
}
|
|
}
|
|
}
|
|
|
|
void DtlsTransport::MaybeStartDtls() {
|
|
if (dtls_ && ice_transport_->writable()) {
|
|
ConfigureHandshakeTimeout();
|
|
|
|
if (dtls_->StartSSL()) {
|
|
// This should never fail:
|
|
// Because we are operating in a nonblocking mode and all
|
|
// incoming packets come in via OnReadPacket(), which rejects
|
|
// packets in this state, the incoming queue must be empty. We
|
|
// ignore write errors, thus any errors must be because of
|
|
// configuration and therefore are our fault.
|
|
RTC_NOTREACHED() << "StartSSL failed.";
|
|
LOG_J(LS_ERROR, this) << "Couldn't start DTLS handshake";
|
|
set_dtls_state(DTLS_TRANSPORT_FAILED);
|
|
return;
|
|
}
|
|
LOG_J(LS_INFO, this) << "DtlsTransport: Started DTLS handshake";
|
|
set_dtls_state(DTLS_TRANSPORT_CONNECTING);
|
|
// Now that the handshake has started, we can process a cached ClientHello
|
|
// (if one exists).
|
|
if (cached_client_hello_.size()) {
|
|
if (ssl_role_ == rtc::SSL_SERVER) {
|
|
LOG_J(LS_INFO, this) << "Handling cached DTLS ClientHello packet.";
|
|
if (!HandleDtlsPacket(cached_client_hello_.data<char>(),
|
|
cached_client_hello_.size())) {
|
|
LOG_J(LS_ERROR, this) << "Failed to handle DTLS packet.";
|
|
}
|
|
} else {
|
|
LOG_J(LS_WARNING, this) << "Discarding cached DTLS ClientHello packet "
|
|
<< "because we don't have the server role.";
|
|
}
|
|
cached_client_hello_.Clear();
|
|
}
|
|
}
|
|
}
|
|
|
|
// Called from OnReadPacket when a DTLS packet is received.
|
|
bool DtlsTransport::HandleDtlsPacket(const char* data, size_t size) {
|
|
// Sanity check we're not passing junk that
|
|
// just looks like DTLS.
|
|
const uint8_t* tmp_data = reinterpret_cast<const uint8_t*>(data);
|
|
size_t tmp_size = size;
|
|
while (tmp_size > 0) {
|
|
if (tmp_size < kDtlsRecordHeaderLen)
|
|
return false; // Too short for the header
|
|
|
|
size_t record_len = (tmp_data[11] << 8) | (tmp_data[12]);
|
|
if ((record_len + kDtlsRecordHeaderLen) > tmp_size)
|
|
return false; // Body too short
|
|
|
|
tmp_data += record_len + kDtlsRecordHeaderLen;
|
|
tmp_size -= record_len + kDtlsRecordHeaderLen;
|
|
}
|
|
|
|
// Looks good. Pass to the SIC which ends up being passed to
|
|
// the DTLS stack.
|
|
return downward_->OnPacketReceived(data, size);
|
|
}
|
|
|
|
void DtlsTransport::set_receiving(bool receiving) {
|
|
if (receiving_ == receiving) {
|
|
return;
|
|
}
|
|
receiving_ = receiving;
|
|
SignalReceivingState(this);
|
|
}
|
|
|
|
void DtlsTransport::set_writable(bool writable) {
|
|
if (writable_ == writable) {
|
|
return;
|
|
}
|
|
LOG_J(LS_VERBOSE, this) << "set_writable from:" << writable_ << " to "
|
|
<< writable;
|
|
writable_ = writable;
|
|
if (writable_) {
|
|
SignalReadyToSend(this);
|
|
}
|
|
SignalWritableState(this);
|
|
}
|
|
|
|
void DtlsTransport::set_dtls_state(DtlsTransportState state) {
|
|
if (dtls_state_ == state) {
|
|
return;
|
|
}
|
|
LOG_J(LS_VERBOSE, this) << "set_dtls_state from:" << dtls_state_ << " to "
|
|
<< state;
|
|
dtls_state_ = state;
|
|
SignalDtlsState(this, state);
|
|
}
|
|
|
|
void DtlsTransport::OnDtlsHandshakeError(rtc::SSLHandshakeError error) {
|
|
SignalDtlsHandshakeError(error);
|
|
}
|
|
|
|
void DtlsTransport::ConfigureHandshakeTimeout() {
|
|
RTC_DCHECK(dtls_);
|
|
rtc::Optional<int> rtt = ice_transport_->GetRttEstimate();
|
|
if (rtt) {
|
|
// Limit the timeout to a reasonable range in case the ICE RTT takes
|
|
// extreme values.
|
|
int initial_timeout = std::max(kMinHandshakeTimeout,
|
|
std::min(kMaxHandshakeTimeout,
|
|
2 * (*rtt)));
|
|
LOG_J(LS_INFO, this) << "configuring DTLS handshake timeout "
|
|
<< initial_timeout << " based on ICE RTT " << *rtt;
|
|
|
|
dtls_->SetInitialRetransmissionTimeout(initial_timeout);
|
|
} else {
|
|
LOG_J(LS_INFO, this)
|
|
<< "no RTT estimate - using default DTLS handshake timeout";
|
|
}
|
|
}
|
|
|
|
|
|
} // namespace cricket
|