/// <summary>
/// Builds the REFER request to initiate an attended transfer on an established call.
/// </summary>
/// <param name="target">A target dialogue representing the Transferee.</param>
/// <returns>A SIP REFER request.</returns>
private SIPRequest GetReferRequest(SIPDialogue target)
{
SIPRequest referRequest = Dialogue.GetInDialogRequest(SIPMethodsEnum.REFER);
SIPURI targetUri = target.RemoteTarget.CopyOf();
referRequest.Header.Contact = new List <SIPContactHeader> {
SIPContactHeader.GetDefaultSIPContactHeader()
};
SIPParameters replacesHeaders = new SIPParameters();
if (target.Direction == SIPCallDirection.Out)
{
replacesHeaders.Set("Replaces", SIPEscape.SIPURIParameterEscape($"{target.CallId};to-tag={target.RemoteTag};from-tag={target.LocalTag}"));
var from = new SIPUserField(target.LocalUserField.Name, target.LocalUserField.URI.CopyOf(), null);
referRequest.Header.ReferredBy = from.ToString();
}
else
{
replacesHeaders.Set("Replaces", SIPEscape.SIPURIParameterEscape($"{target.CallId};to-tag={target.RemoteTag};from-tag={target.LocalTag}"));
var from = new SIPUserField(target.RemoteUserField.Name, target.RemoteUserField.URI.CopyOf(), null);
referRequest.Header.ReferredBy = from.ToString();
}
targetUri.Headers = replacesHeaders;
var referTo = new SIPUserField(null, targetUri, null);
referRequest.Header.ReferTo = referTo.ToString();
return(referRequest);
}
public SIPResponse GetOkResponse(string contentType, string messageBody)
{
SIPResponse okResponse = new SIPResponse(SIPResponseStatusCodesEnum.Ok, null);
okResponse.SetSendFromHints(TransactionRequest.LocalSIPEndPoint);
SIPHeader requestHeader = TransactionRequest.Header;
okResponse.Header = new SIPHeader(
SIPContactHeader.GetDefaultSIPContactHeader(TransactionRequest.URI.Scheme),
requestHeader.From, requestHeader.To,
requestHeader.CSeq,
requestHeader.CallId);
okResponse.Header.To.ToTag = m_localTag;
okResponse.Header.CSeqMethod = requestHeader.CSeqMethod;
okResponse.Header.Vias = requestHeader.Vias;
okResponse.Header.Server = SIPConstants.SipUserAgentVersionString;
okResponse.Header.MaxForwards = Int32.MinValue;
okResponse.Header.RecordRoutes = requestHeader.RecordRoutes;
okResponse.Header.Supported = SIPExtensionHeaders.REPLACES + ", " + SIPExtensionHeaders.NO_REFER_SUB
+ ((PrackSupported == true) ? ", " + SIPExtensionHeaders.PRACK : "");
okResponse.Body = messageBody;
okResponse.Header.ContentType = contentType;
okResponse.Header.ContentLength = (messageBody != null) ? messageBody.Length : 0;
return(okResponse);
}
public SIPResponse GetOkResponse(string contentType, string messageBody)
{
try
{
SIPResponse okResponse = new SIPResponse(SIPResponseStatusCodesEnum.Ok, null);
okResponse.SetSendFromHints(TransactionRequest.LocalSIPEndPoint);
SIPHeader requestHeader = TransactionRequest.Header;
okResponse.Header = new SIPHeader(SIPContactHeader.GetDefaultSIPContactHeader(), requestHeader.From, requestHeader.To, requestHeader.CSeq, requestHeader.CallId);
okResponse.Header.To.ToTag = m_localTag;
okResponse.Header.CSeqMethod = requestHeader.CSeqMethod;
okResponse.Header.Vias = requestHeader.Vias;
okResponse.Header.Server = m_sipServerAgent;
okResponse.Header.MaxForwards = Int32.MinValue;
okResponse.Header.RecordRoutes = requestHeader.RecordRoutes;
okResponse.Header.Supported = (PrackSupported == true) ? SIPExtensionHeaders.PRACK : null;
okResponse.Body = messageBody;
okResponse.Header.ContentType = contentType;
okResponse.Header.ContentLength = (messageBody != null) ? messageBody.Length : 0;
return(okResponse);
}
catch (Exception excp)
{
logger.LogError("Exception GetOkResponse. " + excp.Message);
throw excp;
}
}
/// <summary>
/// Builds the REFER request to transfer an established call.
/// </summary>
/// <param name="sipDialogue">A SIP dialogue object representing the established call.</param>
/// <param name="referToUri">The SIP URI to transfer the call to.</param>
/// <returns>A SIP REFER request.</returns>
private static SIPRequest GetReferRequest(SIPClientUserAgent uac, SIPURI referToUri)
{
SIPDialogue sipDialogue = uac.SIPDialogue;
SIPRequest referRequest = new SIPRequest(SIPMethodsEnum.REFER, sipDialogue.RemoteTarget);
referRequest.SetSendFromHints(uac.ServerTransaction.TransactionRequest.LocalSIPEndPoint);
SIPFromHeader referFromHeader = SIPFromHeader.ParseFromHeader(sipDialogue.LocalUserField.ToString());
SIPToHeader referToHeader = SIPToHeader.ParseToHeader(sipDialogue.RemoteUserField.ToString());
int cseq = sipDialogue.CSeq + 1;
sipDialogue.CSeq++;
SIPHeader referHeader = new SIPHeader(referFromHeader, referToHeader, cseq, sipDialogue.CallId);
referHeader.CSeqMethod = SIPMethodsEnum.REFER;
referRequest.Header = referHeader;
referRequest.Header.Routes = sipDialogue.RouteSet;
referRequest.Header.ProxySendFrom = sipDialogue.ProxySendFrom;
referRequest.Header.Vias.PushViaHeader(SIPViaHeader.GetDefaultSIPViaHeader());
referRequest.Header.ReferTo = referToUri.ToString();
referRequest.Header.Contact = new List <SIPContactHeader>()
{
SIPContactHeader.GetDefaultSIPContactHeader()
};
return(referRequest);
}
private SIPRequest GetDummyINVITERequest(SIPURI dummyURI)
{
string dummyFrom = "<sip:[email protected]>";
SIPRequest inviteRequest = new SIPRequest(SIPMethodsEnum.INVITE, dummyURI);
SIPHeader inviteHeader = new SIPHeader(SIPFromHeader.ParseFromHeader(dummyFrom), new SIPToHeader(null, dummyURI, null), 1, CallProperties.CreateNewCallId());
inviteHeader.From.FromTag = CallProperties.CreateNewTag();
inviteHeader.Contact = new List <SIPContactHeader> {
SIPContactHeader.GetDefaultSIPContactHeader()
};
inviteHeader.CSeqMethod = SIPMethodsEnum.INVITE;
inviteHeader.UserAgent = "unittest";
inviteRequest.Header = inviteHeader;
SIPViaHeader viaHeader = SIPViaHeader.GetDefaultSIPViaHeader();
inviteRequest.Header.Vias.PushViaHeader(viaHeader);
inviteRequest.Body = "dummy";
inviteRequest.Header.ContentLength = inviteRequest.Body.Length;
inviteRequest.Header.ContentType = "application/sdp";
return(inviteRequest);
}
/// <summary>
/// Builds the REFER request to initiate a blind transfer on an established call.
/// </summary>
/// <param name="referToUri">The SIP URI to transfer the call to.</param>
/// <returns>A SIP REFER request.</returns>
private SIPRequest GetReferRequest(SIPURI referToUri)
{
SIPRequest referRequest = Dialogue.GetInDialogRequest(SIPMethodsEnum.REFER);
referRequest.Header.ReferTo = referToUri.ToString();
referRequest.Header.Supported = SIPExtensionHeaders.NO_REFER_SUB;
referRequest.Header.Contact = new List <SIPContactHeader> {
SIPContactHeader.GetDefaultSIPContactHeader()
};
return(referRequest);
}
/// <summary>
/// Sends a re-INVITE request to the remote call party with the supplied SDP.
/// </summary>
private void SendReInviteRequest(SDP sdp)
{
if (Dialogue == null)
{
logger.LogWarning("No dialog available, re-INVITE request cannot be sent.");
}
else
{
Dialogue.SDP = sdp.ToString();
var reinviteRequest = Dialogue.GetInDialogRequest(SIPMethodsEnum.INVITE);
reinviteRequest.Header.UserAgent = m_userAgent;
reinviteRequest.Header.ContentType = m_sdpContentType;
reinviteRequest.Body = sdp.ToString();
reinviteRequest.Header.Supported = SIPExtensionHeaders.PRACK;
if (m_uac != null)
{
reinviteRequest.Header.Contact = m_uac.ServerTransaction.TransactionRequest.Header.Contact;
reinviteRequest.SetSendFromHints(m_uac.ServerTransaction.TransactionRequest.LocalSIPEndPoint);
}
else if (m_uas != null)
{
reinviteRequest.Header.Contact = m_uas.ClientTransaction.TransactionFinalResponse.Header.Contact;
reinviteRequest.SetSendFromHints(m_uas.ClientTransaction.TransactionFinalResponse.LocalSIPEndPoint);
}
else
{
reinviteRequest.Header.Contact = new List <SIPContactHeader>()
{
SIPContactHeader.GetDefaultSIPContactHeader()
};
}
UACInviteTransaction reinviteTransaction = new UACInviteTransaction(m_transport, reinviteRequest, m_outboundProxy);
reinviteTransaction.SendInviteRequest();
reinviteTransaction.UACInviteTransactionFinalResponseReceived += ReinviteRequestFinalResponseReceived;
}
}
/// <summary>
/// Initiates a SUBSCRIBE request to a notification server.
/// </summary>
/// <param name="subscribeURI">The SIP user that dialog notifications are being subscribed to.</param>
public void Subscribe(SIPURI subscribeURI, int expiry, SIPEventPackagesEnum sipEventPackage, string subscribeCallID, SIPURI contactURI)
{
try
{
if (m_attempts >= MAX_SUBSCRIBE_ATTEMPTS)
{
logger.LogWarning($"Subscription to {subscribeURI} reached the maximum number of allowed attempts without a failure condition.");
m_subscribed = false;
SubscriptionFailed?.Invoke(subscribeURI, SIPResponseStatusCodesEnum.InternalServerError, "Subscription reached the maximum number of allowed attempts.");
m_waitForSubscribeResponse.Set();
}
else
{
m_attempts++;
m_localCSeq++;
SIPRequest subscribeRequest = SIPRequest.GetRequest(
SIPMethodsEnum.SUBSCRIBE,
m_resourceURI,
new SIPToHeader(null, subscribeURI, m_subscriptionToTag),
new SIPFromHeader(null, new SIPURI(m_authUsername, m_authDomain, null, m_resourceURI.Scheme, SIPProtocolsEnum.udp), m_subscriptionFromTag));
if (contactURI != null)
{
subscribeRequest.Header.Contact = new List <SIPContactHeader>()
{
new SIPContactHeader(null, contactURI)
};
}
else
{
subscribeRequest.Header.Contact = new List <SIPContactHeader>()
{
SIPContactHeader.GetDefaultSIPContactHeader(subscribeRequest.URI.Scheme)
};
}
subscribeRequest.Header.CSeq = m_localCSeq;
subscribeRequest.Header.Expires = expiry;
subscribeRequest.Header.Event = SIPEventPackageType.GetEventHeader(sipEventPackage);
subscribeRequest.Header.CallId = subscribeCallID;
if (!m_filter.IsNullOrBlank())
{
subscribeRequest.Body = m_filter;
subscribeRequest.Header.ContentLength = m_filter.Length;
subscribeRequest.Header.ContentType = m_filterTextType;
}
SIPNonInviteTransaction subscribeTransaction = new SIPNonInviteTransaction(m_sipTransport, subscribeRequest, m_outboundProxy);
subscribeTransaction.NonInviteTransactionFinalResponseReceived += SubscribeTransactionFinalResponseReceived;
subscribeTransaction.NonInviteTransactionFailed += SubscribeTransactionFailed;
LastSubscribeAttempt = DateTime.Now;
subscribeTransaction.SendRequest();
}
}
catch (Exception excp)
{
logger.LogError("Exception SIPNotifierClient Subscribe. " + excp.Message);
SubscriptionFailed?.Invoke(m_resourceURI, SIPResponseStatusCodesEnum.InternalServerError, "Exception Subscribing. " + excp.Message);
m_waitForSubscribeResponse.Set();
}
}
private SIPRequest GetInviteRequest(SIPCallDescriptor sipCallDescriptor, string branchId, string callId, SIPRouteSet routeSet, string content, string contentType)
{
SIPRequest inviteRequest = new SIPRequest(SIPMethodsEnum.INVITE, sipCallDescriptor.Uri);
SIPHeader inviteHeader = new SIPHeader(sipCallDescriptor.GetFromHeader(), SIPToHeader.ParseToHeader(sipCallDescriptor.To), 1, callId);
inviteHeader.From.FromTag = CallProperties.CreateNewTag();
inviteHeader.Contact = new List <SIPContactHeader>()
{
SIPContactHeader.GetDefaultSIPContactHeader(inviteRequest.URI.Scheme)
};
inviteHeader.Contact[0].ContactURI.User = sipCallDescriptor.Username;
inviteHeader.CSeqMethod = SIPMethodsEnum.INVITE;
inviteHeader.UserAgent = SIPConstants.SipUserAgentVersionString;
inviteHeader.Routes = routeSet;
inviteHeader.Supported = SIPExtensionHeaders.REPLACES + ", " + SIPExtensionHeaders.NO_REFER_SUB
+ ((PrackSupported == true) ? ", " + SIPExtensionHeaders.PRACK : "");
inviteRequest.Header = inviteHeader;
if (!sipCallDescriptor.ProxySendFrom.IsNullOrBlank())
{
inviteHeader.ProxySendFrom = sipCallDescriptor.ProxySendFrom;
}
SIPViaHeader viaHeader = new SIPViaHeader(new IPEndPoint(IPAddress.Any, 0), branchId);
inviteRequest.Header.Vias.PushViaHeader(viaHeader);
inviteRequest.Body = content;
inviteRequest.Header.ContentLength = (inviteRequest.Body != null) ? inviteRequest.Body.Length : 0;
inviteRequest.Header.ContentType = contentType;
try
{
if (sipCallDescriptor.CustomHeaders != null && sipCallDescriptor.CustomHeaders.Count > 0)
{
foreach (string customHeader in sipCallDescriptor.CustomHeaders)
{
if (customHeader.IsNullOrBlank())
{
continue;
}
else if (customHeader.Trim().StartsWith(SIPHeaders.SIP_HEADER_USERAGENT))
{
inviteRequest.Header.UserAgent = customHeader.Substring(customHeader.IndexOf(":") + 1).Trim();
}
else if (customHeader.Trim().StartsWith(SIPHeaders.SIP_HEADER_TO + ":"))
{
var customToHeader = SIPUserField.ParseSIPUserField(customHeader.Substring(customHeader.IndexOf(":") + 1).Trim());
if (customToHeader != null)
{
inviteRequest.Header.To.ToUserField = customToHeader;
}
}
else
{
inviteRequest.Header.UnknownHeaders.Add(customHeader);
}
}
}
}
catch (Exception excp)
{
logger.LogError("Exception Parsing CustomHeader for GetInviteRequest. " + excp.Message + sipCallDescriptor.CustomHeaders);
}
if (AdjustInvite != null)
{
inviteRequest = AdjustInvite(inviteRequest);
}
return(inviteRequest);
}
/// <summary>
/// Because this is a server user agent the SIP transport must start listening for client user agents.
/// </summary>
private async Task OnRequest(SIPEndPoint localSIPEndPoint, SIPEndPoint remoteEndPoint, SIPRequest sipRequest)
{
try
{
var banResult = _sipFail2Ban.IsBanned(remoteEndPoint);
if (banResult == BanReasonsEnum.None)
{
if (sipRequest.Header.From != null &&
sipRequest.Header.From.FromTag != null &&
sipRequest.Header.To != null &&
sipRequest.Header.To.ToTag != null)
{
_sipCallManager.ProcessInDialogueRequest(localSIPEndPoint, remoteEndPoint, sipRequest);
}
else
{
switch (sipRequest.Method)
{
case SIPMethodsEnum.BYE:
case SIPMethodsEnum.CANCEL:
// BYE's and CANCEL's should always have dialog fields set.
SIPResponse badResponse = SIPResponse.GetResponse(sipRequest, SIPResponseStatusCodesEnum.BadRequest, null);
await _sipTransport.SendResponseAsync(badResponse);
break;
case SIPMethodsEnum.INVITE:
if (!await WasRejected(sipRequest))
{
_logger.LogInformation($"Incoming call request: {localSIPEndPoint}<-{remoteEndPoint} {sipRequest.URI}.");
_b2bUserAgentCore.AddInviteRequest(sipRequest);
}
break;
case SIPMethodsEnum.OPTIONS:
SIPResponse optionsResponse = SIPResponse.GetResponse(sipRequest, SIPResponseStatusCodesEnum.Ok, null);
optionsResponse.Header.Contact = new List <SIPContactHeader> {
SIPContactHeader.GetDefaultSIPContactHeader(sipRequest.URI.Scheme)
};
optionsResponse.Header.Server = SIPConstants.SIP_USERAGENT_STRING;
await _sipTransport.SendResponseAsync(optionsResponse);
break;
case SIPMethodsEnum.REGISTER:
if (!await WasRejected(sipRequest))
{
_registrarCore.AddRegisterRequest(localSIPEndPoint, remoteEndPoint, sipRequest);
}
break;
case SIPMethodsEnum.SUBSCRIBE:
if (!await WasRejected(sipRequest))
{
_subscriberCore.AddSubscribeRequest(localSIPEndPoint, remoteEndPoint, sipRequest);
}
break;
default:
var notAllowedResp = SIPResponse.GetResponse(sipRequest, SIPResponseStatusCodesEnum.MethodNotAllowed, null);
await _sipTransport.SendResponseAsync(notAllowedResp);
break;
}
}
}
else
{
_logger.LogWarning($"Ban list hit for {remoteEndPoint} and {banResult} dropped request {sipRequest.StatusLine}, user agent {sipRequest.Header.UserAgent}.");
}
}
catch (Exception reqExcp)
{
_logger.LogWarning($"Exception handling {sipRequest.Method}. {reqExcp.Message}");
}
}
