/// <summary>
/// Updates the session after receiving the remote SDP.
/// At this point check that the codecs match. We currently only support:
/// - Audio: PCMU,
/// - Video: VP8.
/// If they are not available there's no point carrying on.
/// </summary>
/// <param name="sessionDescription">The answer/offer SDP from the remote party.</param>
public override void setRemoteDescription(RTCSessionDescription sessionDescription)
{
remoteDescription = sessionDescription;
var audioAnnounce = sessionDescription.sdp.Media.Where(x => x.Media == SDPMediaTypesEnum.audio).FirstOrDefault();
if (audioAnnounce != null)
{
var audioTrack = new MediaStreamTrack(audioAnnounce.MediaID, SDPMediaTypesEnum.audio, true, audioAnnounce.MediaFormats);
addTrack(audioTrack);
}
var videoAnnounce = sessionDescription.sdp.Media.Where(x => x.Media == SDPMediaTypesEnum.video).FirstOrDefault();
if (videoAnnounce != null)
{
var videoTrack = new MediaStreamTrack(videoAnnounce.MediaID, SDPMediaTypesEnum.video, true, videoAnnounce.MediaFormats);
addTrack(videoTrack);
}
SdpSessionID = sessionDescription.sdp.SessionId;
RemoteIceUser = sessionDescription.sdp.IceUfrag ?? sessionDescription.sdp.Media.First().IceUfrag;
RemoteIcePassword = sessionDescription.sdp.IcePwd ?? sessionDescription.sdp.Media.First().IcePwd;
// All browsers seem to have gone to trickling ICE candidates now but just
// in case one or more are given we can start the STUN dance immediately.
if (sessionDescription.sdp.IceCandidates != null)
{
foreach (var iceCandidate in sessionDescription.sdp.IceCandidates)
{
AppendRemoteIceCandidate(iceCandidate);
}
}
foreach (var media in sessionDescription.sdp.Media)
{
if (media.IceCandidates != null)
{
foreach (var iceCandidate in media.IceCandidates)
{
AppendRemoteIceCandidate(iceCandidate);
}
}
}
}
/// <summary>
/// Sets the local SDP.
/// </summary>
/// <remarks>
/// As specified in https://www.w3.org/TR/webrtc/#dom-peerconnection-setlocaldescription.
/// </remarks>
/// <param name="description">Optional. The session description to set as
/// local description. If not supplied then an offer or answer will be created as required.
/// </param>
public Task setLocalDescription(RTCSessionDescriptionInit init)
{
RTCSessionDescription description = new RTCSessionDescription {
type = init.type, sdp = SDP.ParseSDPDescription(init.sdp)
};
localDescription = description;
if (init.type == RTCSdpType.offer)
{
_rtpIceChannel.IsController = true;
}
// This is the point the ICE session potentially starts contacting STUN and TURN servers.
//IceSession.StartGathering();
signalingState = RTCSignalingState.have_local_offer;
onsignalingstatechange?.Invoke();
return(Task.CompletedTask);
}
/// <summary>
/// Updates the session after receiving the remote SDP.
/// At this point check that the codecs match. We currently only support:
/// - Audio: PCMU,
/// - Video: VP8.
/// If they are not available there's no point carrying on.
/// </summary>
/// <param name="sessionDescription">The answer/offer SDP from the remote party.</param>
public SetDescriptionResultEnum setRemoteDescription(RTCSessionDescriptionInit init)
{
RTCSessionDescription description = new RTCSessionDescription {
type = init.type, sdp = SDP.ParseSDPDescription(init.sdp)
};
remoteDescription = description;
SDP remoteSdp = SDP.ParseSDPDescription(init.sdp);
SdpType sdpType = (init.type == RTCSdpType.offer) ? SdpType.offer : SdpType.answer;
var setResult = base.SetRemoteDescription(sdpType, remoteSdp);
if (setResult == SetDescriptionResultEnum.OK)
{
string remoteIceUser = remoteSdp.IceUfrag;
string remoteIcePassword = remoteSdp.IcePwd;
string dtlsFingerprint = remoteSdp.DtlsFingerprint;
var audioAnnounce = remoteSdp.Media.Where(x => x.Media == SDPMediaTypesEnum.audio).FirstOrDefault();
if (audioAnnounce != null)
{
remoteIceUser = remoteIceUser ?? audioAnnounce.IceUfrag;
remoteIcePassword = remoteIcePassword ?? audioAnnounce.IcePwd;
dtlsFingerprint = dtlsFingerprint ?? audioAnnounce.DtlsFingerprint;
}
var videoAnnounce = remoteSdp.Media.Where(x => x.Media == SDPMediaTypesEnum.video).FirstOrDefault();
if (videoAnnounce != null)
{
if (remoteIceUser == null || remoteIcePassword == null || dtlsFingerprint == null)
{
remoteIceUser = remoteIceUser ?? videoAnnounce.IceUfrag;
remoteIcePassword = remoteIcePassword ?? videoAnnounce.IcePwd;
dtlsFingerprint = dtlsFingerprint ?? videoAnnounce.DtlsFingerprint;
}
}
SdpSessionID = remoteSdp.SessionId;
if (init.type == RTCSdpType.answer)
{
_rtpIceChannel.IsController = true;
// Set DTLS role to be server.
IceRole = IceRolesEnum.passive;
}
else
{
// Set DTLS role to be server.
// As of 20 Jun 2020 the DTLS handshake logic is based on OpenSSL and the mechanism
// used hands over the socket handle to the C++ class. This logic works a lot better
// when acting as the server in the handshake.
IceRole = IceRolesEnum.passive;
}
if (remoteIceUser != null && remoteIcePassword != null)
{
_rtpIceChannel.SetRemoteCredentials(remoteIceUser, remoteIcePassword);
}
if (!string.IsNullOrWhiteSpace(dtlsFingerprint))
{
dtlsFingerprint = dtlsFingerprint.Trim().ToLower();
if (dtlsFingerprint.Length < DTLS_FINGERPRINT_DIGEST.Length + 1)
{
logger.LogWarning($"The DTLS fingerprint was too short.");
return(SetDescriptionResultEnum.DtlsFingerprintDigestNotSupported);
}
else if (!dtlsFingerprint.StartsWith(DTLS_FINGERPRINT_DIGEST))
{
logger.LogWarning($"The DTLS fingerprint was supplied with an unsupported digest function (supported one is {DTLS_FINGERPRINT_DIGEST}): {dtlsFingerprint}.");
return(SetDescriptionResultEnum.DtlsFingerprintDigestNotSupported);
}
else
{
dtlsFingerprint = dtlsFingerprint.Substring(DTLS_FINGERPRINT_DIGEST.Length + 1).Trim().Replace(":", "").Replace(" ", "");
RemotePeerDtlsFingerprint = ByteBufferInfo.ParseHexStr(dtlsFingerprint);
logger.LogDebug($"The DTLS fingerprint for the remote peer's SDP {ByteBufferInfo.HexStr(RemotePeerDtlsFingerprint)}.");
}
}
else
{
logger.LogWarning("The DTLS fingerprint was missing from the remote party's session description.");
return(SetDescriptionResultEnum.DtlsFingerprintMissing);
}
// All browsers seem to have gone to trickling ICE candidates now but just
// in case one or more are given we can start the STUN dance immediately.
if (remoteSdp.IceCandidates != null)
{
foreach (var iceCandidate in remoteSdp.IceCandidates)
{
addIceCandidate(new RTCIceCandidateInit {
candidate = iceCandidate
});
}
}
foreach (var media in remoteSdp.Media)
{
if (media.IceCandidates != null)
{
foreach (var iceCandidate in media.IceCandidates)
{
addIceCandidate(new RTCIceCandidateInit {
candidate = iceCandidate
});
}
}
}
signalingState = RTCSignalingState.have_remote_offer;
onsignalingstatechange?.Invoke();
}
return(setResult);
}
/// <summary>
/// Updates the session after receiving the remote SDP.
/// At this point check that the codecs match. We currently only support:
/// - Audio: PCMU,
/// - Video: VP8.
/// If they are not available there's no point carrying on.
/// </summary>
/// <param name="sessionDescription">The answer/offer SDP from the remote party.</param>
public SetDescriptionResultEnum setRemoteDescription(RTCSessionDescriptionInit init)
{
RTCSessionDescription description = new RTCSessionDescription {
type = init.type, sdp = SDP.ParseSDPDescription(init.sdp)
};
remoteDescription = description;
SDP remoteSdp = SDP.ParseSDPDescription(init.sdp);
SdpType sdpType = (init.type == RTCSdpType.offer) ? SdpType.offer : SdpType.answer;
var setResult = base.SetRemoteDescription(sdpType, remoteSdp);
if (setResult == SetDescriptionResultEnum.OK)
{
string remoteIceUser = remoteSdp.IceUfrag;
string remoteIcePassword = remoteSdp.IcePwd;
string dtlsFingerprint = remoteSdp.DtlsFingerprint;
var audioAnnounce = remoteSdp.Media.Where(x => x.Media == SDPMediaTypesEnum.audio).FirstOrDefault();
if (audioAnnounce != null)
{
remoteIceUser = remoteIceUser ?? audioAnnounce.IceUfrag;
remoteIcePassword = remoteIcePassword ?? audioAnnounce.IcePwd;
dtlsFingerprint = dtlsFingerprint ?? audioAnnounce.DtlsFingerprint;
}
var videoAnnounce = remoteSdp.Media.Where(x => x.Media == SDPMediaTypesEnum.video).FirstOrDefault();
if (videoAnnounce != null)
{
if (remoteIceUser == null || remoteIcePassword == null || dtlsFingerprint == null)
{
remoteIceUser = remoteIceUser ?? videoAnnounce.IceUfrag;
remoteIcePassword = remoteIcePassword ?? videoAnnounce.IcePwd;
dtlsFingerprint = dtlsFingerprint ?? videoAnnounce.DtlsFingerprint;
}
}
SdpSessionID = remoteSdp.SessionId;
if (init.type == RTCSdpType.answer)
{
_rtpIceChannel.IsController = true;
// Set DTLS role to be server.
IceRole = IceRolesEnum.passive;
}
else
{
// Set DTLS role as client.
IceRole = IceRolesEnum.active;
}
if (remoteIceUser != null && remoteIcePassword != null)
{
_rtpIceChannel.SetRemoteCredentials(remoteIceUser, remoteIcePassword);
}
if (!string.IsNullOrWhiteSpace(dtlsFingerprint))
{
dtlsFingerprint = dtlsFingerprint.Trim().ToLower();
if (RTCDtlsFingerprint.TryParse(dtlsFingerprint, out var remoteFingerprint))
{
RemotePeerDtlsFingerprint = remoteFingerprint;
}
else
{
logger.LogWarning($"The DTLS fingerprint was invalid or not supported.");
return(SetDescriptionResultEnum.DtlsFingerprintDigestNotSupported);
}
}
else
{
logger.LogWarning("The DTLS fingerprint was missing from the remote party's session description.");
return(SetDescriptionResultEnum.DtlsFingerprintMissing);
}
// All browsers seem to have gone to trickling ICE candidates now but just
// in case one or more are given we can start the STUN dance immediately.
if (remoteSdp.IceCandidates != null)
{
foreach (var iceCandidate in remoteSdp.IceCandidates)
{
addIceCandidate(new RTCIceCandidateInit {
candidate = iceCandidate
});
}
}
foreach (var media in remoteSdp.Media)
{
if (media.IceCandidates != null)
{
foreach (var iceCandidate in media.IceCandidates)
{
addIceCandidate(new RTCIceCandidateInit {
candidate = iceCandidate
});
}
}
}
signalingState = RTCSignalingState.have_remote_offer;
onsignalingstatechange?.Invoke();
}
return(setResult);
}
