RTC: Support drop for specified PT

trunk/conf/full.conf

@@ -497,6 +497,9 @@ vhost rtc.vhost.srs.com {
         # The version of dtls, support dtls1.0, dtls1.2, and auto
         # default: auto
         dtls_version auto;
+        # Drop the packet with the pt(payload type), 0 never drop.
+        # default: 0
+        drop_for_pt 0;
     }
     # whether enable min delay mode for vhost.
     # default: on, for RTC.

trunk/src/app/srs_app_config.cpp

@@ -3935,7 +3935,7 @@ srs_error_t SrsConfig::check_normal_config()
                 for (int j = 0; j < (int)conf->directives.size(); j++) {
                     string m = conf->at(j)->name;
                     if (m != "enabled" && m != "bframe" && m != "aac" && m != "stun_timeout" && m != "stun_strict_check"
-                        && m != "dtls_role" && m != "dtls_version") {
+                        && m != "dtls_role" && m != "dtls_version" && m != "drop_for_pt") {
                         return srs_error_new(ERROR_SYSTEM_CONFIG_INVALID, "illegal vhost.rtc.%s of %s", m.c_str(), vhost->arg0().c_str());
                     }
                 }
@@ -5056,6 +5056,23 @@ std::string SrsConfig::get_rtc_dtls_version(string vhost)
     return conf->arg0();
 }
 
+int SrsConfig::get_rtc_drop_for_pt(string vhost)
+{
+    static int DEFAULT = 0;
+
+    SrsConfDirective* conf = get_vhost(vhost);
+    if (!conf) {
+        return DEFAULT;
+    }
+
+    conf = conf->get("drop_for_pt");
+    if (!conf || conf->arg0().empty()) {
+        return DEFAULT;
+    }
+
+    return ::atoi(conf->arg0().c_str());
+}
+
 bool SrsConfig::get_rtc_nack_enabled(string vhost)
 {
     static bool DEFAULT = true;

trunk/src/app/srs_app_config.hpp

@@ -546,6 +546,7 @@ public:
     bool get_rtc_stun_strict_check(std::string vhost);
     std::string get_rtc_dtls_role(std::string vhost);
     std::string get_rtc_dtls_version(std::string vhost);
+    int get_rtc_drop_for_pt(std::string vhost);
     bool get_rtc_nack_enabled(std::string vhost);
     bool get_rtc_twcc_enabled(std::string vhost);
 

trunk/src/app/srs_app_rtc_conn.cpp

@@ -855,6 +855,7 @@ SrsRtcPublisher::SrsRtcPublisher(SrsRtcSession* session)
     source = NULL;
     nn_simulate_nack_drop = 0;
     nack_enabled_ = false;
+    pt_to_drop_ = 0;
 
     nn_audio_frames = 0;
     twcc_ext_id_ = 0;
@@ -892,9 +893,10 @@ srs_error_t SrsRtcPublisher::initialize(uint32_t vssrc, uint32_t assrc, uint8_t
     }
     // TODO: FIXME: Support reload.
     nack_enabled_ = _srs_config->get_rtc_nack_enabled(session_->req->vhost);
+    pt_to_drop_ = (uint16_t)_srs_config->get_rtc_drop_for_pt(session_->req->vhost);
 
-    srs_trace("RTC publisher video(ssrc=%u), audio(ssrc=%u), nack=%d",
+    srs_trace("RTC publisher video(ssrc=%u), audio(ssrc=%u), nack=%d, pt-drop=%u",
-        video_ssrc, audio_ssrc, nack_enabled_);
+        video_ssrc, audio_ssrc, nack_enabled_, pt_to_drop_);
 
     if ((err = report_timer->tick(0 * SRS_UTIME_MILLISECONDS)) != srs_success) {
         return srs_error_wrap(err, "hourglass tick");
@@ -1133,6 +1135,7 @@ srs_error_t SrsRtcPublisher::on_twcc(uint16_t sn) {
     srs_utime_t now = srs_get_system_time();
     return rtcp_twcc_.recv_packet(sn, now);
 }
+
 srs_error_t SrsRtcPublisher::on_rtp(char* data, int nb_data)
 {
     srs_error_t err = srs_success;
@@ -1144,18 +1147,21 @@ srs_error_t SrsRtcPublisher::on_rtp(char* data, int nb_data)
         return err;
     }
 
-    // We must parse the TWCC from RTP header before SRTP unprotect, because:
+    // Decode the header first.
-    //      1. Client may send some padding packets with invalid SequenceNumber, which causes the SRTP fail.
+    SrsRtpHeader h;
-    //      2. Server may send multiple duplicated NACK to client, and got more than one ARQ packet, which also fail SRTP.
+    if (pt_to_drop_ && twcc_ext_id_) {
-    // so, we must parse the header before SRTP unprotect(which may fail and drop packet).
+        SrsBuffer b(data, nb_data);
-    if (0 != twcc_ext_id_) {
+        h.ignore_padding(true); h.set_extensions(&extension_types_);
-        SrsBuffer b(data, nb_data); SrsRtpHeader h;
-        h.ignore_padding(true);
-        h.set_extensions(&extension_types_);
         if ((err = h.decode(&b)) != srs_success) {
             return srs_error_wrap(err, "twcc decode header");
         }
+    }
 
+    // We must parse the TWCC from RTP header before SRTP unprotect, because:
+    //      1. Client may send some padding packets with invalid SequenceNumber, which causes the SRTP fail.
+    //      2. Server may send multiple duplicated NACK to client, and got more than one ARQ packet, which also fail SRTP.
+    // so, we must parse the header before SRTP unprotect(which may fail and drop packet).
+    if (twcc_ext_id_) {
         uint16_t twcc_sn = 0;
         if ((err = h.get_twcc_sequence_number(twcc_sn)) == srs_success) {
             if((err = on_twcc(twcc_sn)) != srs_success) {
@@ -1166,6 +1172,11 @@ srs_error_t SrsRtcPublisher::on_rtp(char* data, int nb_data)
         }
     }
 
+    // If payload type is configed to drop, ignore this packet.
+    if (pt_to_drop_ && pt_to_drop_ == h.get_payload_type()) {
+        return err;
+    }
+
     // Decrypt the cipher to plaintext RTP data.
     int nb_unprotected_buf = nb_data;
     char* unprotected_buf = new char[kRtpPacketSize];

trunk/src/app/srs_app_rtc_conn.hpp

@@ -251,6 +251,9 @@ private:
     SrsRtcSession* session_;
     uint32_t video_ssrc;
     uint32_t audio_ssrc;
+    uint16_t pt_to_drop_;
+    // Whether enabled nack.
+    bool nack_enabled_;
 private:
     bool request_keyframe_;
     SrsRtpRingBuffer* video_queue_;
@@ -260,8 +263,6 @@ private:
 private:
     SrsRequest* req;
     SrsRtcSource* source;
-    // Whether enabled nack.
-    bool nack_enabled_;
     // Simulators.
     int nn_simulate_nack_drop;
 private: