feat: 增加webrtc代理拉流 (#4389)

- 增加客户端模式，支持主动拉流、推流：
   - addStreamProxy接口新增支持whep主动拉流，拉流地址目前只兼容zlm的whep url。
   - addStreamPusherProxy接口新增支持whip主动推流，推流地址目前只兼容zlm的whip url。
   - 以上推流url格式为webrtc[s]://server_host:server_port/app/stream_id?key=value, 内部会自动转换为http[s]://server_host:server_port/index/api/[whip/whep]?app=app&stream=stream_id&key=value。

- 增加WebRtc p2p 模式：
  - 增加 ICE FULL模式。
  - 增加STUN/TURN 服务器。
  - 增加websocket 信令。
  - 增加P2P代理拉流。

---------

Co-authored-by: xia-chu <771730766@qq.com>
Co-authored-by: mtdxc <mtdxc@126.com>
Co-authored-by: cqm <cqm@97kid.com>

webrtc/IceSession.cpp

@@ -0,0 +1,139 @@
+/*
+ * Copyright (c) 2016-present The ZLMediaKit project authors. All Rights Reserved.
+ *
+ * This file is part of ZLMediaKit(https://github.com/ZLMediaKit/ZLMediaKit).
+ *
+ * Use of this source code is governed by MIT-like license that can be found in the
+ * LICENSE file in the root of the source tree. All contributing project authors
+ * may be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "IceSession.hpp"
+#include "Util/util.h"
+#include "Common/config.h"
+#include "WebRtcTransport.h"
+
+using namespace std;
+using namespace toolkit;
+
+namespace mediakit {
+
+static IceSession::Ptr queryIceTransport(uint8_t *data, size_t size) {
+    auto packet = RTC::StunPacket::parse((const uint8_t *)data, size);
+    if (!packet) {
+        WarnL << "parse stun error";
+        return nullptr;
+    }
+
+    auto username = packet->getUsername();
+    return IceSessionManager::Instance().getItem(username);
+}
+
+////////////  IceSession //////////////////////////
+IceSession::IceSession(const Socket::Ptr &sock) : Session(sock) {
+    TraceL << getIdentifier();
+    _over_tcp = sock->sockType() == SockNum::Sock_TCP;
+    GET_CONFIG(string, iceUfrag, Rtc::kIceUfrag);
+    GET_CONFIG(string, icePwd, Rtc::kIcePwd);
+    _ice_transport = std::make_shared<IceServer>(this, iceUfrag, icePwd, getPoller());
+    _ice_transport->initialize();
+}
+
+IceSession::~IceSession() {
+    TraceL << getIdentifier();
+}
+
+EventPoller::Ptr IceSession::queryPoller(const Buffer::Ptr &buffer) {
+    auto transport = queryIceTransport((uint8_t *)buffer->data(), buffer->size());
+    return transport ? transport->getPoller() : nullptr;
+}
+
+void IceSession::onRecv(const Buffer::Ptr &buffer) {
+    // TraceL;
+    if (_over_tcp) {
+        input(buffer->data(), buffer->size());
+    }
+    else{
+        onRecv_l(buffer->data(), buffer->size());
+    }
+}
+
+void IceSession::onRecv_l(const char* buffer, size_t size) {
+    if (!_session_pair) {
+        _session_pair = std::make_shared<IceTransport::Pair>(shared_from_this());
+    }
+    _ice_transport->processSocketData((const uint8_t *)buffer, size, _session_pair);
+}
+
+void IceSession::onError(const SockException &err) {
+    InfoL;
+    // 消除循环引用
+    _session_pair = nullptr;
+}
+
+void IceSession::onManager() {
+}
+
+ssize_t IceSession::onRecvHeader(const char *data, size_t len) {
+    onRecv_l(data + 2, len - 2);
+    return 0;
+}
+
+const char *IceSession::onSearchPacketTail(const char *data, size_t len) {
+    if (len < 2) {
+        // Not enough data
+        return nullptr;
+    }
+    uint16_t length = (((uint8_t *)data)[0] << 8) | ((uint8_t *)data)[1];
+    if (len < (size_t)(length + 2)) {
+        // Not enough data
+        return nullptr;
+    }
+    // Return the end of the RTP packet
+    return data + 2 + length;
+}
+
+void IceSession::onIceTransportRecvData(const toolkit::Buffer::Ptr& buffer, const IceTransport::Pair::Ptr& pair) {
+    _ice_transport->processSocketData((const uint8_t *)buffer->data(), buffer->size(), pair);
+}
+
+void IceSession::onIceTransportGatheringCandidate(const IceTransport::Pair::Ptr& pair, const CandidateInfo& candidate) {
+    DebugL << candidate.dumpString();
+}
+
+void IceSession::onIceTransportDisconnected() {
+    InfoL << getIdentifier();
+}
+
+void IceSession::onIceTransportCompleted() {
+    InfoL << getIdentifier();
+}
+
+////////////  IceSessionManager //////////////////////////
+
+IceSessionManager &IceSessionManager::Instance() {
+    static IceSessionManager s_instance;
+    return s_instance;
+}
+
+void IceSessionManager::addItem(const std::string& key, const IceSession::Ptr &ptr) {
+    std::lock_guard<std::mutex> lck(_mtx);
+    _map[key] = ptr;
+}
+
+IceSession::Ptr IceSessionManager::getItem(const std::string& key) {
+    assert(!key.empty());
+    std::lock_guard<std::mutex> lck(_mtx);
+    auto it = _map.find(key);
+    if (it == _map.end()) {
+        return nullptr;
+    }
+    return it->second.lock();
+}
+
+void IceSessionManager::removeItem(const std::string& key) {
+    std::lock_guard<std::mutex> lck(_mtx);
+    _map.erase(key);
+}
+
+}// namespace mediakit