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Validate SDP offers and answers

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itchyonion 2023-03-14 12:39:57 -07:00
parent 8e5ea82611
commit 07b5f07452
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GPG key ID: 4B87B720348500EA
3 changed files with 56 additions and 13 deletions
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17
proxy/lib/snowflake.go
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@ -250,6 +250,8 @@ func (s *SignalingServer) pollOffer(sid string, proxyType string, acceptedRelayP
return nil, ""
}
// sendAnswer encodes an SDP answer, sends it to the broker
// and wait for its response
func (s *SignalingServer) sendAnswer(sid string, pc *webrtc.PeerConnection) error {
ld := pc.LocalDescription()
if !s.keepLocalAddresses {
@ -485,6 +487,10 @@ func (sf *SnowflakeProxy) makePeerConnectionFromOffer(sdp *webrtc.SessionDescrip
// Wait for ICE candidate gathering to complete
<-done
if !strings.Contains(pc.LocalDescription().SDP, "\na=candidate:") {
return nil, fmt.Errorf("SDP answer contains no candidate")
}
log.Printf("Answer: \n\t%s", strings.ReplaceAll(pc.LocalDescription().SDP, "\n", "\n\t"))
return pc, nil
@ -524,15 +530,16 @@ func (sf *SnowflakeProxy) makeNewPeerConnection(config webrtc.Configuration,
pc.Close()
return nil, err
}
log.Println("Probetest: Creating offer")
log.Println("Probetest: Created Offer")
// As of v3.0.0, pion-webrtc uses trickle ICE by default.
// We have to wait for candidate gathering to complete
// before we send the offer
done := webrtc.GatheringCompletePromise(pc)
// start the gathering of ICE candidates
err = pc.SetLocalDescription(offer)
if err != nil {
log.Println("Failed to prepare offer", err)
log.Println("Failed to apply offer", err)
pc.Close()
return nil, err
}
@ -540,6 +547,11 @@ func (sf *SnowflakeProxy) makeNewPeerConnection(config webrtc.Configuration,
// Wait for ICE candidate gathering to complete
<-done
if !strings.Contains(pc.LocalDescription().SDP, "\na=candidate:") {
return nil, fmt.Errorf("Probetest SDP offer contains no candidate")
}
return pc, nil
}
@ -701,7 +713,6 @@ func (sf *SnowflakeProxy) checkNATType(config webrtc.Configuration, probeURL str
log.Printf("Error parsing url: %s", err.Error())
}
// create offer used for probetest
dataChan := make(chan struct{})
pc, err := sf.makeNewPeerConnection(config, dataChan)
if err != nil {