private async Task Forward(UASInviteTransaction uasTx, ISIPAccount callerSIPAccount)
{
var invReq = uasTx.TransactionRequest;
//uasTx.TransactionStateChanged += (tx) => Logger.LogDebug($"B2B uas tx state changed to {tx.TransactionState}.");
//uasTx.TransactionTraceMessage += (tx, msg) => Logger.LogDebug($"B2B uas tx trace message. {msg}");
Logger.LogDebug($"B2B commencing forward for caller {invReq.Header.From.FromURI} to {invReq.URI}.");
SIPB2BUserAgent b2bua = new SIPB2BUserAgent(_sipTransport, null, uasTx, callerSIPAccount);
bool isAuthenticated = false;
if (callerSIPAccount != null)
{
isAuthenticated = b2bua.AuthenticateCall();
}
if (callerSIPAccount == null || isAuthenticated == true)
{
b2bua.CallAnswered += (uac, resp) => ForwardCallAnswered(uac, b2bua);
var dst = await _sipdialPlan.Lookup(uasTx, null);
if (dst == null)
{
Logger.LogInformation($"B2BUA lookup did not return a destination. Rejecting UAS call.");
var notFoundResp = SIPResponse.GetResponse(uasTx.TransactionRequest, SIPResponseStatusCodesEnum.NotFound, null);
uasTx.SendFinalResponse(notFoundResp);
OnAcceptCallFailure?.Invoke(uasTx.TransactionRequest.RemoteSIPEndPoint, CallFailureEnum.NotFound, invReq);
}
else
{
Logger.LogInformation($"B2BUA forwarding call to {dst.Uri}.");
b2bua.Call(dst);
}
}
}
/// <summary>
/// Attempts to lookup the caller based on the "To" header host. If the host matches a
/// hosted domain then an attempt will be made to retrieve the SIP account for the caller.
/// If a SIP account is not found for a hosted domain the call is rejected with a 403 response.
/// If the host does not match then the caller is treated as a public non-authenticated caller.
/// </summary>
/// <returns>The caller's SIP account or null for non-hosted domains.</returns>
private async Task <ISIPAccount> GetCaller(UASInviteTransaction uasTx)
{
var invReq = uasTx.TransactionRequest;
if (invReq.Header.From == null || invReq.Header.From.FromURI == null)
{
uasTx.SendFinalResponse(SIPResponse.GetResponse(invReq, SIPResponseStatusCodesEnum.BadRequest, "From header malformed"));
return(null);
}
else
{
string canonicalDomain = _sipDomainManager.GetCanonicalDomain(invReq.Header.From.FromURI.HostAddress);
if (canonicalDomain == null)
{
// The caller is from a non-hosted domain. Will be treated as a public non-authenticated caller.
return(null);
}
else
{
Logger.LogDebug($"B2B incoming caller was for hosted domain {canonicalDomain}, looking up caller for {invReq.Header.From.FromURI.User}.");
var sipAccount = await _sipAccountDataLayer.GetSIPAccount(invReq.Header.From.FromURI.User, canonicalDomain);
if (sipAccount == null)
{
Logger.LogWarning($"B2B no SIP account found for caller {invReq.Header.From.FromURI.User}@{canonicalDomain}, rejecting.");
uasTx.SendFinalResponse(SIPResponse.GetResponse(invReq, SIPResponseStatusCodesEnum.Forbidden, null));
OnAcceptCallFailure?.Invoke(uasTx.TransactionRequest.RemoteSIPEndPoint, CallFailureEnum.NoSIPAccount, invReq);
}
return(sipAccount);
}
}
}