ZLMediaKit/webrtc/WebRtcTransport.cpp
2021-04-02 21:08:40 +08:00

324 lines
11 KiB
C++

#include "WebRtcTransport.h"
#include <iostream>
#include "Rtcp/Rtcp.h"
WebRtcTransport::WebRtcTransport(const EventPoller::Ptr &poller) {
_dtls_transport = std::make_shared<RTC::DtlsTransport>(poller, this);
_ice_server = std::make_shared<RTC::IceServer>(this, makeRandStr(4), makeRandStr(24));
}
void WebRtcTransport::onDestory(){
_dtls_transport = nullptr;
_ice_server = nullptr;
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void WebRtcTransport::OnIceServerSendStunPacket(const RTC::IceServer *iceServer, const RTC::StunPacket *packet, RTC::TransportTuple *tuple) {
onSendSockData((char *) packet->GetData(), packet->GetSize(), (struct sockaddr_in *) tuple);
}
void WebRtcTransport::OnIceServerSelectedTuple(const RTC::IceServer *iceServer, RTC::TransportTuple *tuple) {
InfoL;
}
void WebRtcTransport::OnIceServerConnected(const RTC::IceServer *iceServer) {
InfoL;
}
void WebRtcTransport::OnIceServerCompleted(const RTC::IceServer *iceServer) {
InfoL;
if (_answer_sdp->media[0].role == DtlsRole::passive) {
_dtls_transport->Run(RTC::DtlsTransport::Role::SERVER);
} else {
_dtls_transport->Run(RTC::DtlsTransport::Role::CLIENT);
}
}
void WebRtcTransport::OnIceServerDisconnected(const RTC::IceServer *iceServer) {
InfoL;
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void WebRtcTransport::OnDtlsTransportConnected(
const RTC::DtlsTransport *dtlsTransport,
RTC::SrtpSession::CryptoSuite srtpCryptoSuite,
uint8_t *srtpLocalKey,
size_t srtpLocalKeyLen,
uint8_t *srtpRemoteKey,
size_t srtpRemoteKeyLen,
std::string &remoteCert) {
InfoL;
_srtp_session_send = std::make_shared<RTC::SrtpSession>(RTC::SrtpSession::Type::OUTBOUND, srtpCryptoSuite, srtpLocalKey, srtpLocalKeyLen);
_srtp_session_recv = std::make_shared<RTC::SrtpSession>(RTC::SrtpSession::Type::OUTBOUND, srtpCryptoSuite, srtpRemoteKey, srtpRemoteKeyLen);
onStartWebRTC();
}
void WebRtcTransport::OnDtlsTransportSendData(const RTC::DtlsTransport *dtlsTransport, const uint8_t *data, size_t len) {
onSendSockData((char *)data, len);
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void WebRtcTransport::onSendSockData(const char *buf, size_t len, bool flush){
auto tuple = _ice_server->GetSelectedTuple();
assert(tuple);
onSendSockData(buf, len, (struct sockaddr_in *) tuple, flush);
}
const RtcSession& WebRtcTransport::getSdp(SdpType type) const{
switch (type) {
case SdpType::offer: return *_offer_sdp;
case SdpType::answer: return *_answer_sdp;
default: throw std::invalid_argument("不识别的sdp类型");
}
}
string getFingerprint(const string &algorithm_str, const std::shared_ptr<RTC::DtlsTransport> &transport){
auto algorithm = RTC::DtlsTransport::GetFingerprintAlgorithm(algorithm_str);
for (auto &finger_prints : transport->GetLocalFingerprints()) {
if (finger_prints.algorithm == algorithm) {
return finger_prints.value;
}
}
throw std::invalid_argument(StrPrinter << "不支持的加密算法:" << algorithm_str);
}
void WebRtcTransport::setRemoteDtlsFingerprint(const RtcSession &remote){
//设置远端dtls签名
RTC::DtlsTransport::Fingerprint remote_fingerprint;
remote_fingerprint.algorithm = RTC::DtlsTransport::GetFingerprintAlgorithm(_offer_sdp->media[0].fingerprint.algorithm);
remote_fingerprint.value = _offer_sdp->media[0].fingerprint.hash;
_dtls_transport->SetRemoteFingerprint(remote_fingerprint);
}
void WebRtcTransport::onCheckSdp(SdpType type, RtcSession &sdp) const{
for (auto &m : sdp.media) {
if (m.type != TrackApplication && !m.rtcp_mux) {
throw std::invalid_argument("只支持rtcp-mux模式");
}
}
if (sdp.group.mids.empty()) {
throw std::invalid_argument("只支持group BUNDLE模式");
}
}
std::string WebRtcTransport::getAnswerSdp(const string &offer){
//// 解析offer sdp ////
_offer_sdp = std::make_shared<RtcSession>();
_offer_sdp->loadFrom(offer);
onCheckSdp(SdpType::offer, *_offer_sdp);
setRemoteDtlsFingerprint(*_offer_sdp);
//// sdp 配置 ////
SdpAttrFingerprint fingerprint;
fingerprint.algorithm = _offer_sdp->media[0].fingerprint.algorithm;
fingerprint.hash = getFingerprint(fingerprint.algorithm, _dtls_transport);
RtcConfigure configure;
configure.setDefaultSetting(_ice_server->GetUsernameFragment(), _ice_server->GetPassword(), RtpDirection::sendrecv, fingerprint);
onRtcConfigure(configure);
//// 生成answer sdp ////
_answer_sdp = configure.createAnswer(*_offer_sdp);
onCheckSdp(SdpType::answer, *_answer_sdp);
auto str = _answer_sdp->toString();
TraceL << "\r\n" << str;
return str;
}
bool is_dtls(char *buf) {
return ((*buf > 19) && (*buf < 64));
}
bool is_rtp(char *buf) {
RtpHeader *header = (RtpHeader *) buf;
return ((header->pt < 64) || (header->pt >= 96));
}
bool is_rtcp(char *buf) {
RtpHeader *header = (RtpHeader *) buf;
return ((header->pt >= 64) && (header->pt < 96));
}
void WebRtcTransport::inputSockData(char *buf, size_t len, RTC::TransportTuple *tuple) {
if (RTC::StunPacket::IsStun((const uint8_t *) buf, len)) {
RTC::StunPacket *packet = RTC::StunPacket::Parse((const uint8_t *) buf, len);
if (packet == nullptr) {
WarnL << "parse stun error" << std::endl;
return;
}
_ice_server->ProcessStunPacket(packet, tuple);
return;
}
if (is_dtls(buf)) {
_dtls_transport->ProcessDtlsData((uint8_t *) buf, len);
return;
}
if (is_rtp(buf)) {
if (_srtp_session_recv->DecryptSrtp((uint8_t *) buf, &len)) {
onRtp(buf, len);
}
return;
}
if (is_rtcp(buf)) {
if (_srtp_session_recv->DecryptSrtcp((uint8_t *) buf, &len)) {
onRtcp(buf, len);
}
return;
}
}
void WebRtcTransport::sendRtpPacket(char *buf, size_t len, bool flush) {
const uint8_t *p = (uint8_t *) buf;
bool ret = false;
if (_srtp_session_send) {
ret = _srtp_session_send->EncryptRtp(&p, &len);
}
if (ret) {
onSendSockData((char *) p, len, flush);
}
}
///////////////////////////////////////////////////////////////////////////////////
WebRtcTransportImp::Ptr WebRtcTransportImp::create(const EventPoller::Ptr &poller){
WebRtcTransportImp::Ptr ret(new WebRtcTransportImp(poller), [](WebRtcTransportImp *ptr){
ptr->onDestory();
delete ptr;
});
return ret;
}
WebRtcTransportImp::WebRtcTransportImp(const EventPoller::Ptr &poller) : WebRtcTransport(poller) {
_socket = Socket::createSocket(poller, false);
//随机端口,绑定全部网卡
_socket->bindUdpSock(0);
_socket->setOnRead([this](const Buffer::Ptr &buf, struct sockaddr *addr, int addr_len) mutable {
inputSockData(buf->data(), buf->size(), addr);
});
}
void WebRtcTransportImp::onDestory() {
WebRtcTransport::onDestory();
}
void WebRtcTransportImp::attach(const RtspMediaSource::Ptr &src) {
assert(src);
_src = src;
}
void WebRtcTransportImp::onStartWebRTC() {
if (!canSendRtp()) {
return;
}
_reader = _src->getRing()->attach(_socket->getPoller(), true);
weak_ptr<WebRtcTransportImp> weak_self = shared_from_this();
_reader->setReadCB([weak_self](const RtspMediaSource::RingDataType &pkt){
auto strongSelf = weak_self.lock();
if (!strongSelf) {
return;
}
size_t i = 0;
pkt->for_each([&](const RtpPacket::Ptr &rtp) {
strongSelf->onSendRtp(rtp, ++i == pkt->size());
});
});
}
void WebRtcTransportImp::onSendRtp(const RtpPacket::Ptr &rtp, bool flush){
if (!_send_rtp_pt[rtp->type]) {
//忽略,对方不支持该编码类型
return;
}
auto tmp = rtp->getHeader()->pt;
//设置pt
rtp->getHeader()->pt = _send_rtp_pt[rtp->type];
sendRtpPacket(rtp->data() + RtpPacket::kRtpTcpHeaderSize, rtp->size() - RtpPacket::kRtpTcpHeaderSize, flush);
//还原pt
rtp->getHeader()->pt = tmp;
}
bool WebRtcTransportImp::canSendRtp() const{
auto &sdp = getSdp(SdpType::answer);
return sdp.media[0].direction == RtpDirection::sendrecv || sdp.media[0].direction == RtpDirection::sendonly;
}
void WebRtcTransportImp::onCheckSdp(SdpType type, RtcSession &sdp) const{
WebRtcTransport::onCheckSdp(type, sdp);
if (type != SdpType::answer || !canSendRtp()) {
return;
}
for (auto &m : sdp.media) {
if (m.type == TrackApplication) {
continue;
}
m.rtp_ssrc.ssrc = _src->getSsrc(m.type);
m.rtp_ssrc.cname = "zlmediakit-rtc";
auto rtsp_media = _rtsp_send_sdp.getMedia(m.type);
if (rtsp_media && getCodecId(rtsp_media->plan[0].codec) == getCodecId(m.plan[0].codec)) {
_send_rtp_pt[m.type] = m.plan[0].pt;
}
}
}
void WebRtcTransportImp::onRtcConfigure(RtcConfigure &configure) const {
WebRtcTransport::onRtcConfigure(configure);
_rtsp_send_sdp.loadFrom(_src->getSdp(), false);
configure.audio.enable = false;
configure.video.enable = false;
for (auto &m : _rtsp_send_sdp.media) {
switch (m.type) {
case TrackVideo: {
configure.video.enable = true;
configure.video.preferred_codec.insert(configure.video.preferred_codec.begin(), getCodecId(m.plan[0].codec));
break;
}
case TrackAudio: {
configure.audio.enable = true;
configure.audio.preferred_codec.insert(configure.audio.preferred_codec.begin(),getCodecId(m.plan[0].codec));
break;
}
default:
break;
}
}
configure.addCandidate(*getIceCandidate());
}
void WebRtcTransportImp::onSendSockData(const char *buf, size_t len, struct sockaddr_in *dst, bool flush) {
auto ptr = BufferRaw::create();
ptr->assign(buf, len);
_socket->send(ptr, (struct sockaddr *)(dst), sizeof(struct sockaddr), flush);
}
SdpAttrCandidate::Ptr WebRtcTransportImp::getIceCandidate() const{
auto candidate = std::make_shared<SdpAttrCandidate>();
candidate->foundation = "udpcandidate";
candidate->component = 1;
candidate->transport = "udp";
candidate->priority = 100;
candidate->address = SockUtil::get_local_ip();
candidate->port = _socket->get_local_port();
candidate->type = "host";
return candidate;
}
void WebRtcTransportImp::onRtp(const char *buf, size_t len) {
RtpHeader *rtp = (RtpHeader *) buf;
}
void WebRtcTransportImp::onRtcp(const char *buf, size_t len) {
RtcpHeader *rtcp = (RtcpHeader *) buf;
}
///////////////////////////////////////////////////////////////////