//---------------------------------------------------------------------
// Event handling methods called by SipClientTransaction.
/// <summary>
/// Handles messages received by a transport to be processed by this agent.
/// </summary>
/// <param name="transport">The source transport.</param>
/// <param name="message">The received message.</param>
public void OnReceive(ISipTransport transport, SipMessage message)
{
SipResponse response = (SipResponse)message;
SipClientTransaction transaction;
string transactionID;
if (response == null)
{
return; // Ignore any requests
}
// Route the message to the correct transaction.
if (!response.TryGetTransactionID(out transactionID))
{
return;
}
using (TimedLock.Lock(this))
{
if (!transactions.TryGetValue(transactionID, out transaction))
{
// The response doesn't map to an existing transaction.
// We're going to pass this to the core's OnUncorrelatedResponse()
// method.
core.OnUncorrelatedResponse(this, response);
return;
}
}
transaction.OnResponse(transport, response);
}
/// <summary>
/// Returns a deep clone of the response.
/// </summary>
/// <returns>The cloned <see cref="SipResponse" />.</returns>
public SipResponse Clone()
{
var clone = new SipResponse(status, reasonPhrase, base.SipVersion);
clone.CopyFrom(this);
return(clone);
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="request">The initiating <see cref="SipRequest" />.</param>
/// <param name="dialog">The <see cref="SipDialog" /> for requests that initiate a dialog (or <c>null</c>).</param>
/// <param name="agent">The <see cref="ISipAgent" /> that sent the request and received the response.</param>
/// <param name="response">The final <see cref="SipResponse" />.</param>
public SipResult(SipRequest request, SipDialog dialog, ISipAgent agent, SipResponse response)
{
this.Request = request;
this.Response = response;
this.Status = response.Status;
this.Dialog = dialog;
this.Agent = agent;
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="request">The initiating <see cref="SipRequest" />.</param>
/// <param name="dialog">The <see cref="SipDialog" /> for requests that initiate a dialog (or <c>null</c>).</param>
/// <param name="agent">The <see cref="ISipAgent" /> that sent the request and received the response.</param>
/// <param name="status">The final operation status.</param>
public SipResult(SipRequest request, SipDialog dialog, ISipAgent agent, SipStatus status)
{
this.Request = request;
this.Response = null;
this.Status = status;
this.Dialog = dialog;
this.Agent = agent;
}
/// <summary>
/// Constuctor.
/// </summary>
/// <param name="dialog">The <see cref="SipDialog" />.</param>
/// <param name="transaction">The <see cref="SipTransaction" /> associated with the event (or <c>null</c>).</param>
/// <param name="core">The <see cref="SipCore" /> that raised the event.</param>
/// <param name="clientRequest">Pass the <see cref="SipRequest" /> received for server side dialog creation (or <c>null</c>).</param>
/// <param name="serverResult">The <see cref="SipResult" /> returned by the server, completing its side of the dialog creation (or <c>null</c>).</param>
internal SipDialogEventArgs(SipDialog dialog, SipTransaction transaction, SipCore core, SipRequest clientRequest, SipResult serverResult)
{
this.Dialog = dialog;
this.Transaction = transaction;
this.Core = core;
this.ClientRequest = clientRequest;
this.ServerResult = serverResult;
this.Response = null;
}
/// <summary>
/// Constuctor.
/// </summary>
/// <param name="status">The <see cref="SipStatus" />.</param>
/// <param name="response">The received <see cref="SipResponse" /> (or <c>null</c>).</param>
/// <param name="transaction">The <see cref="SipClientTransaction" />.</param>
/// <param name="dialog">The associated <see cref="SipDialog" /> (or <c>null</c>).</param>
/// <param name="agent">The <see cref="SipClientAgent" /> that processed the response.</param>
/// <param name="core">The <see cref="SipCore" /> that raised the event.</param>
internal SipResponseEventArgs(SipStatus status, SipResponse response, SipClientTransaction transaction,
SipDialog dialog, SipClientAgent agent, SipCore core)
{
this.Status = status;
this.Response = response;
this.Transaction = transaction;
this.Dialog = dialog;
this.Agent = agent;
this.Core = core;
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="agent">The <see cref="ISipAgent" /> that owns this transaction.</param>
/// <param name="id">The globally unique transaction ID.</param>
/// <param name="transport">The <see cref="ISipTransport" /> to be used for this transaction.</param>
/// <param name="ttd">(Time-to-die) The time (SYS) where the transaction should terminate itself regardless of its current state.</param>
public SipServerTransaction(SipServerAgent agent, string id, ISipTransport transport, DateTime ttd)
: base(agent, id, transport)
{
this.ttd = ttd;
this.agent = (SipServerAgent)agent;
this.transport = transport;
this.isUdp = !transport.IsStreaming;
this.request = null;
this.remoteEP = null;
this.provisionalResponse = null;
this.finalResponse = null;
}
/// <summary>
/// Constructs B2BUA event arguments for a received <see cref="SipResponse" />.
/// </summary>
/// <param name="core">The <see cref="SipCore" /> that raised the event.</param>
/// <param name="b2bUserAgent">The <see cref="SipB2BUserAgent{TState}" /> that raised the event.</param>
/// <param name="session">The <see cref="SipB2BUASession{TState}" /> associated with the event.</param>
/// <param name="receivedResponse">The received <see cref="SipResponse" />.</param>
/// <param name="response">The proposed <see cref="SipResponse" /> to be forwarded.</param>
internal SipB2BUAEventArgs(SipCore core,
SipB2BUserAgent <TState> b2bUserAgent,
SipB2BUASession <TState> session,
SipResponse receivedResponse,
SipResponse response)
{
Assertion.Test(receivedResponse != null);
Assertion.Test(response != null);
this.Core = core;
this.B2BUserAgent = b2bUserAgent;
this.Session = session;
this.ReceivedResponse = receivedResponse;
this.Response = response;
}
/// <summary>
/// Called when a non-INVITE transaction completes.
/// </summary>
/// <param name="transaction">The source <see cref="SipClientTransaction" />.</param>
/// <param name="status">The completion status.</param>
/// <param name="response">The final response (or <c>null</c>).</param>
/// <remarks>
/// <para>
/// The <paramref name="response"/> parameter will be passed as <c>null</c> if
/// the transaction was completed without receiving a final message (such
/// as a timeout). In this case, the agent should look to the <paramref name="status"/>
/// property for the final disposition of the transaction.
/// </para>
/// <para>
/// This method also handles the resubmission of the request with additional
/// authentication information if necessary.
/// </para>
/// </remarks>
internal void OnComplete(SipClientTransaction transaction, SipStatus status, SipResponse response)
{
var arClient = (ClientAsyncResult)transaction.AgentState;
if (response == null)
{
// The operation has completed without receiving a final response (probably
// due to a time out or some kind of transport related problem).
arClient.SipResult = new SipResult(arClient.Request, arClient.Dialog, this, status);
arClient.Notify();
core.OnResponseReceived(new SipResponseEventArgs(status, response, transaction, arClient.Dialog, this, this.core));
return;
}
// We have the final response.
arClient.SipResult = new SipResult(arClient.Request, arClient.Dialog, this, response);
arClient.Notify();
core.OnResponseReceived(new SipResponseEventArgs(response.Status, response, transaction, arClient.Dialog, this, this.core));
}
/// <summary>
/// Creates a <see cref="SipResponse" /> for this request, copying the minimum
/// required headers from the request to the response.
/// </summary>
/// <param name="status">The status code.</param>
/// <param name="reasonPhrase">The reason phrase (or <c>null</c>).</param>
/// <returns>The <see cref="SipResponse" />.</returns>
/// <remarks>
/// <para>
/// The procedure for doing this is described in RFC 3261 on page 50.
/// </para>
/// <note>
/// This method assumes that the <b>tag</b> parameter on the <b>To</b>
/// header has already been added (if necessary).
/// </note>
/// </remarks>
public SipResponse CreateResponse(SipStatus status, string reasonPhrase)
{
SipResponse response = new SipResponse(status, reasonPhrase, this.SipVersion);
SipHeader header;
header = this[SipHeader.Via];
if (header != null)
{
response.Headers.Add(SipHeader.Via, header.Clone());
}
header = this[SipHeader.To];
if (header != null)
{
response.Headers.Add(SipHeader.To, header.Clone());
}
header = this[SipHeader.From];
if (header != null)
{
response.Headers.Add(SipHeader.From, header.Clone());
}
header = this[SipHeader.CallID];
if (header != null)
{
response.Headers.Add(SipHeader.CallID, header.Clone());
}
header = this[SipHeader.CSeq];
if (header != null)
{
response.Headers.Add(SipHeader.CSeq, header.Clone());
}
return(response);
}
/// <summary>
/// The managing <see cref="ISipAgent" /> is responsible for calling this
/// method whenever it receives requests correlated to this transaction.
/// </summary>
/// <param name="request">The received <see cref="SipRequest" />.</param>
public void OnRequest(SipRequest request)
{
SipRequest callbackMsg = null;
bool callOnRequest = false;
bool callOnInviteBegin = false;
bool callOnInviteComplete = false;
try
{
request.SourceTransaction = this;
using (TimedLock.Lock(agent))
{
if (this.request == null)
{
SipViaValue viaValue;
SipContactValue toValue;
NetworkBinding sentBy;
IPAddress address;
// This is the initial transaction request.
this.request = request;
// Handle the Via "received" and "rport" header parameters (mostly) as described on page
// RFC 3261 (page 145) and RFC 3581 (page 4).
viaValue = request.GetHeader <SipViaValue>(SipHeader.Via);
if (viaValue == null)
{
// Illegal request
SetState(SipTransactionState.Terminated);
return;
}
sentBy = viaValue.SentByBinding;
if (sentBy == null || sentBy.IsHost || sentBy.Address != request.RemoteEndpoint.Address)
{
viaValue.Received = request.RemoteEndpoint.Address.ToString();
}
if (viaValue.RPort != null)
{
viaValue.RPort = request.RemoteEndpoint.Port.ToString();
}
// Determine the destination network endpoint based on the
// rules described on RFC 3261 (page 146).
if (request.SourceTransport.IsStreaming)
{
// $todo(jeff.lill):
//
// This implementation is incomplete. To be fully
// compliant with the RFC, I'd have to check to
// see if the connection is still present in the
// transport and if not, use the received and
// rport values as described.
remoteEP = request.RemoteEndpoint;
}
else
{
if (viaValue.MAddr != null)
{
if (!IPAddress.TryParse(viaValue.MAddr, out address))
{
SipException e;
// Illegal request
SetState(SipTransactionState.Terminated);
e = new SipException("Illegal request: Invalid [Via: maddr].");
e.Transport = transport.Name;
e.SourceEndpoint = request.RemoteEndpoint;
e.BadMessage = request;
throw e;
}
remoteEP = new NetworkBinding(address, viaValue.SentByBinding.Port);
}
else
{
remoteEP = request.RemoteEndpoint;
}
}
// INVITE and non-INVITE requests have different state machines.
if (request.Method == SipMethod.Invite)
{
// Start an INVITE transaction
SetState(SipTransactionState.InviteProceeding);
// If the request has a "To" header without a "tag" parameter then
// generate a tag. Note that this code will cause provisional INVITE
// responses to include a generated tag which the RFC indicates
// SHOULD NOT be done. But, it's much safer to do this once here
// for all transaction types, avoiding special cases, and besides,
// I've noticed that Asterisk includes a tag in its provisional
// INVITE responses.
toValue = request.GetHeader <SipContactValue>(SipHeader.To);
if (toValue != null)
{
if (toValue["tag"] == null)
{
toValue["tag"] = SipHelper.GenerateTagID();
}
request.SetHeader(SipHeader.To, toValue);
}
// Always send an initial provisional trying response.
provisionalResponse = request.CreateResponse(SipStatus.Trying, null);
SendResponse(provisionalResponse);
// Setup to call the agent's OnInviteBegin() method.
callOnInviteBegin = true;
callbackMsg = request;
}
else if (request.Method == SipMethod.Ack)
{
// Allow an ACK request to drop through to the state machine.
}
else
{
// Start a non-INVITE transaction
SetState(SipTransactionState.Trying);
// Setup to call the agent's OnRequest() method.
callOnRequest = true;
callbackMsg = request;
}
return;
}
// Handle state specific processing
switch (base.State)
{
default:
case SipTransactionState.Unknown:
SysLog.LogError("Unexpected SIP transaction state.");
SetState(SipTransactionState.Terminated);
return;
case SipTransactionState.InviteCalling:
break;
case SipTransactionState.InviteProceeding:
if (provisionalResponse != null)
{
transport.Send(remoteEP, provisionalResponse);
}
break;
case SipTransactionState.InviteCompleted:
if (request.Method == SipMethod.Ack)
{
SetState(SipTransactionState.InviteConfirmed);
// Setup to call OnInviteComplete(ack);
callOnInviteComplete = true;
callbackMsg = request;
return;
}
Assertion.Test(finalResponse != null);
transport.Send(remoteEP, finalResponse);
break;
case SipTransactionState.InviteConfirmed:
break;
case SipTransactionState.Trying:
break;
case SipTransactionState.Proceeding:
Assertion.Test(provisionalResponse != null);
transport.Send(remoteEP, provisionalResponse);
break;
case SipTransactionState.Completed:
Assertion.Test(finalResponse != null);
transport.Send(remoteEP, finalResponse);
break;
case SipTransactionState.Terminated:
break;
}
}
}
finally
{
// Handle the agent callbacks outside of the lock to avoid
// deadlock issues.
if (callOnRequest)
{
agent.OnRequest(this, callbackMsg);
}
if (callOnInviteBegin)
{
agent.OnInviteBegin(this, request);
}
if (callOnInviteComplete)
{
agent.OnInviteComplete(this, this.request, finalResponse, callbackMsg);
}
}
}
/// <summary>
/// Creates the proper ACK request based on the original INVITE request sent
/// to the server and the 2xx response received.
/// </summary>
/// <param name="inviteRequest">The INVITE <see cref="SipRequest" /> sent to the server.</param>
/// <param name="response">The 2xx <see cref="SipResponse" /> received from the server.</param>
/// <returns>The created ACK <see cref="SipRequest" />.</returns>
private SipRequest CreateAckRequest(SipRequest inviteRequest, SipResponse response)
{
SipRequest ackRequest;
SipHeader callID;
SipHeader to;
SipHeader from;
SipHeader via;
SipHeader contact;
SipHeader route;
SipCSeqValue vCSeq;
if (inviteRequest.Method != SipMethod.Invite)
{
throw new ArgumentException("INVITE request expected.", "inviteRequest");
}
if (response.IsProvisional)
{
throw new ArgumentException("Non-provisional response expected.", "response");
}
ackRequest = new SipRequest(SipMethod.Ack, inviteRequest.Uri, null);
callID = inviteRequest[SipHeader.CallID];
to = response[SipHeader.To];
from = inviteRequest[SipHeader.From];
via = inviteRequest[SipHeader.Via];
contact = inviteRequest[SipHeader.Contact];
route = inviteRequest[SipHeader.Route];
if (callID == null)
{
throw new SipException("INVITE request is missing header: [Call-ID]");
}
if (to == null)
{
throw new SipException("INVITE response is missing header: [To]");
}
if (from == null)
{
throw new SipException("INVITE request is missing header: [From]");
}
if (contact == null)
{
throw new SipException("INVITE request is missing header: [Contact]");
}
if (via == null)
{
throw new SipException("INVITE request is missing header: [Via]");
}
vCSeq = inviteRequest.GetHeader <SipCSeqValue>(SipHeader.CSeq);
if (vCSeq == null)
{
throw new SipException("INVITE request is missing header: [CSeq]");
}
ackRequest.AddHeader(SipHeader.Via, via.Text);
ackRequest.AddHeader(SipHeader.To, to.Text);
ackRequest.AddHeader(SipHeader.From, from.Text);
ackRequest.AddHeader(SipHeader.Contact, contact.Text);
ackRequest.AddHeader(SipHeader.CallID, callID.Text);
ackRequest.AddHeader(SipHeader.CSeq, new SipCSeqValue(vCSeq.Number, "ACK"));
ackRequest.AddHeader(SipHeader.MaxForwards, SipHelper.MaxForwards);
ackRequest.AddHeader(SipHeader.UserAgent, agent.Core.Settings.UserAgent);
if (route != null)
{
ackRequest.Headers.Add(SipHeader.Route, route.Clone());
}
return(ackRequest);
}
/// <summary>
/// Called when a transaction receives a 1xx response.
/// </summary>
/// <param name="transaction">The source <see cref="SipClientTransaction" />.</param>
/// <param name="response">The <see cref="SipResponse" /> received.</param>
internal void OnProceeding(SipClientTransaction transaction, SipResponse response)
{
var arClient = (ClientAsyncResult)transaction.AgentState;
core.OnResponseReceived(new SipResponseEventArgs(response.Status, response, transaction, arClient.Dialog, this, this.core));
}
/// <summary>
/// This method will be called periodically on a background thread to handle
/// message resending as well as timeout related state transitions.
/// </summary>
public override void OnBkTask()
{
bool callOnComplete = false;
bool callOnProceeding = false;
SipResponse callbackMsg = null;
SipStatus status = SipStatus.OK;
try
{
using (TimedLock.Lock(agent))
{
switch (base.State)
{
default:
case SipTransactionState.Unknown:
break;
case SipTransactionState.InviteCalling:
if (base.TimerB.HasFired)
{
// Request has timed out.
SetState(SipTransactionState.Terminated);
// Setup to call the agent's completion method
callOnComplete = true;
callbackMsg = null;
status = SipStatus.RequestTimeout;
return;
}
if (base.TimerA.HasFired)
{
// Retransmit the request and reset the
// timer for exponential backoff
transport.Send(remoteEP, request);
base.TimerA.Interval = new TimeSpan(base.TimerA.Interval.Ticks * 2);
}
break;
case SipTransactionState.InviteProceeding:
if (base.TimerB.HasFired)
{
// Request has timed out.
SetState(SipTransactionState.Terminated);
// Setup to call the agent's completion method
callOnComplete = true;
callbackMsg = null;
status = SipStatus.RequestTimeout;
return;
}
break;
case SipTransactionState.InviteCompleted:
if (base.TimerD.HasFired)
{
SetState(SipTransactionState.Terminated);
}
break;
case SipTransactionState.Trying:
if (base.TimerF.HasFired)
{
// Request has timed out.
SetState(SipTransactionState.Terminated);
// Setup to call the agent's completion method
callOnComplete = true;
callbackMsg = null;
status = SipStatus.RequestTimeout;
return;
}
if (isUdp && base.TimerE.HasFired)
{
// Retransmit for UDP
transport.Send(remoteEP, request);
base.TimerE.Interval = Helper.Min(base.BaseTimers.T2, Helper.Multiply(base.TimerE.Interval, 2));
}
break;
case SipTransactionState.Proceeding:
if (base.TimerF.HasFired)
{
// Request has timed out.
SetState(SipTransactionState.Terminated);
// Setup to call the agent's completion method
callOnComplete = true;
callbackMsg = null;
status = SipStatus.RequestTimeout;
return;
}
if (base.TimerE.HasFired)
{
// Retransmit for all transports.
transport.Send(remoteEP, request);
base.TimerE.Interval = base.BaseTimers.T2;
}
break;
case SipTransactionState.Completed:
if (base.TimerK.HasFired)
{
SetState(SipTransactionState.Terminated);
}
break;
case SipTransactionState.Terminated:
break;
}
}
}
finally
{
// Handle the agent callbacks outside of the lock to avoid
// deadlock issues.
if (callOnComplete)
{
agent.OnComplete(this, status, callbackMsg);
}
if (callOnProceeding)
{
agent.OnProceeding(this, (SipResponse)callbackMsg);
}
}
}
/// <summary>
/// The managing <see cref="ISipAgent" /> is responsible for calling this
/// method whenever it receives responses correlated to this transaction.
/// </summary>
/// <param name="transport">The source <see cref="ISipTransport" />.</param>
/// <param name="response">The received <see cref="SipResponse" />.</param>
public void OnResponse(ISipTransport transport, SipResponse response)
{
bool callOnComplete = false;
bool callOnProceeding = false;
bool callOnInviteComplete = false;
SipResponse callbackMsg = null;
SipStatus status = SipStatus.OK;
SipCSeqValue vCSeq;
this.transport = transport;
try
{
response.SourceTransaction = this;
using (TimedLock.Lock(agent))
{
// Ignore messages without a sequence number
//
// $todo(jeff.lill): Probably should check the method too
vCSeq = response.GetHeader <SipCSeqValue>(SipHeader.CSeq);
if (vCSeq == null)
{
return;
}
// Handle state specific processing
switch (base.State)
{
default:
case SipTransactionState.Unknown:
SysLog.LogError("Unexpected SIP transaction state.");
SetState(SipTransactionState.Terminated);
// Setup to call the agent's completion method
callOnComplete = true;
callbackMsg = null;
status = SipStatus.Stack_ProtocolError;
return;
case SipTransactionState.InviteCalling:
if (!request.MatchCSeq(response))
{
return; // Ignore responses whose CSeq header doesn't match the request
}
if (response.IsProvisional)
{
// Provisional response.
SetState(SipTransactionState.InviteProceeding);
// Setup to call the agent's proceeding method
callOnProceeding = true;
callbackMsg = response;
status = response.Status;
return;
}
if (response.IsNonSuccessFinal)
{
// Final response non-2xx response. Generate and
// send the ACK request to the server to squelch
// any further responses and then enter the
// InviteCompleted state to absorb any responses
// that do make it through.
ackRequest = CreateAckRequest(request, response);
transport.Send(remoteEP, ackRequest);
SetState(SipTransactionState.InviteCompleted);
// Setup to call the agent's invite completed method
callOnInviteComplete = true;
callbackMsg = response;
status = response.Status;
return;
}
// Must be a 2xx response. Setup to call the agent's
// completed method and enter the terminated state
// without sending an ACK request.
//
// Note that the agent is required to do this as
// described in RFC 3261 on pages 128-129.
SetState(SipTransactionState.Terminated);
callOnInviteComplete = true;
callbackMsg = response;
status = response.Status;
break;
case SipTransactionState.InviteProceeding:
if (!request.MatchCSeq(response))
{
return; // Ignore responses whose CSeq header doesn't match the request
}
if (response.IsProvisional)
{
// Setup to call the agent's proceeding method
callOnProceeding = true;
callbackMsg = response;
status = response.Status;
return;
}
if (response.IsNonSuccessFinal)
{
// Final response non-2xx response. Generate and
// send the ACK request to the server to squelch
// any further responses and then enter the
// InviteCompleted state to absorb any responses
// that do make it through.
// $todo(jeff.lill):
//
// I need to figure out a way to
// map to the dialog so that it
// can generate the ACK rather than
// doing this locally.
ackRequest = CreateAckRequest(request, response);
transport.Send(remoteEP, ackRequest);
SetState(SipTransactionState.InviteCompleted);
// Setup to call the agent's invite completed method
callOnInviteComplete = true;
callbackMsg = response;
status = response.Status;
return;
}
// Must be a 2xx response. Setup to call the agent's
// completed method and enter the terminated state
// without sending an ACK request.
//
// Note that the agent is required to do this as
// described in RFC 3261 on pages 128-129.
SetState(SipTransactionState.Terminated);
callOnInviteComplete = true;
callbackMsg = response;
status = response.Status;
break;
case SipTransactionState.InviteCompleted:
// Retransmit the ACK if we get another final response
if (response.IsFinal)
{
transport.Send(remoteEP, ackRequest);
}
break;
case SipTransactionState.Trying:
if (!request.MatchCSeq(response))
{
return; // Ignore responses whose CSeq header doesn't match the request
}
if (response.IsProvisional)
{
// Provisional response.
SetState(SipTransactionState.Proceeding);
// Setup to call the agent's proceeding method
callOnProceeding = true;
callbackMsg = response;
status = response.Status;
return;
}
else
{
// Final response
SetState(SipTransactionState.Completed);
// Setup to call the agent's completion method
callOnComplete = true;
callbackMsg = response;
status = response.Status;
return;
}
case SipTransactionState.Proceeding:
if (!request.MatchCSeq(response))
{
return; // Ignore responses whose CSeq header doesn't match the request
}
if (response.IsProvisional)
{
// Setup to call the agent's proceeding method
callOnProceeding = true;
callbackMsg = response;
status = response.Status;
return;
}
// Final response.
SetState(SipTransactionState.Completed);
// Setup to call the agent's completion method
callOnComplete = true;
callbackMsg = response;
status = response.Status;
return;
case SipTransactionState.Completed:
break;
case SipTransactionState.Terminated:
break;
}
}
}
finally
{
// Handle the agent callbacks outside of the lock to avoid
// deadlock issues.
if (callOnProceeding)
{
agent.OnProceeding(this, callbackMsg);
}
if (callOnComplete)
{
agent.OnComplete(this, status, callbackMsg);
}
if (callOnInviteComplete)
{
agent.OnInviteComplete(this, status, response);
}
}
}
/// <summary>
/// Called when an INVITE transaction completes.
/// </summary>
/// <param name="transaction">The source <see cref="SipClientTransaction" />.</param>
/// <param name="status">The completion status.</param>
/// <param name="response">The final response (or <c>null</c>).</param>
/// <remarks>
/// <para>
/// The <paramref name="response"/> parameter will be passed as <c>null</c> if
/// the transaction was completed without receiving a final message (such
/// as a timeout). In this case, the agent should look to the <paramref name="status"/>
/// property for the final disposition of the transaction.
/// </para>
/// <para>
/// This method also handles the resubmission of the request with additional
/// authentication information if necessary.
/// </para>
/// <para>
/// The method may create a custom ACK <see cref="SipResponse" /> to be delivered
/// back to the server by saving the response in the <paramref name="response"/> parameter.
/// Otherwise, if this value is left as <c>null</c>, the client transaction will
/// generate a default ACK response and send it.
/// </para>
/// </remarks>
internal void OnInviteComplete(SipClientTransaction transaction, SipStatus status, SipResponse response)
{
var arClient = (ClientAsyncResult)transaction.AgentState;
var args = new SipResponseEventArgs(status, response, transaction, arClient.Dialog, this, this.core);
if (response == null)
{
// The operation has completed without receiving a final response (probably
// due to a time out or some kind of transport related problem).
arClient.SipResult = new SipResult(arClient.Request, arClient.Dialog, this, status);
arClient.Notify();
core.OnResponseReceived(args);
core.OnInviteFailed(args, status);
return;
}
// We have the final response. Compute the dialog ID from the response's
// Call-ID, and To/From tags and assign it to the dialog.
arClient.Dialog.ID = SipDialog.GetDialogID(response);
// Call the core's OnInviteConfirmed() method so it can perform
// any dialog specific activities.
if (response.IsSuccess)
{
core.OnInviteConfirmed(args);
}
else
{
core.OnInviteFailed(args, status);
}
// Signal completion of the async operation.
arClient.SipResult = new SipResult(arClient.Request, arClient.Dialog, this, response);
arClient.Notify();
}
/// <summary>
/// Parses a <see cref="SipRequest" /> or <see cref="SipResponse" /> from the
/// <paramref name="buffer"/> byte array passed.
/// </summary>
/// <param name="buffer">The UTF-8 encoded SIP message data.</param>
/// <param name="isCompletePacket"><c>true</c> if <paramref name="buffer" /> includes both the message header and payload.</param>
/// <returns>A <see cref="SipRequest" /> or <see cref="SipResponse" />.</returns>
/// <remarks>
/// <para>
/// This method is used internally by <see cref="ISipTransport" /> implementations to
/// convert raw data read from the transport into SIP messages. This method supports
/// two basic situations:
/// </para>
/// <list type="bullet">
/// <item>
/// The transport is packet oriented (aka UDP) and the buffer passed includes
/// both the SIP message header and content information. In this case, you
/// need to pass <paramref name="isCompletePacket"/> as <c>true</c>, and the
/// SIP message returned will be complete, with the <see cref="Contents" />
/// property set to the payload bytes.
/// </item>
/// <item>
/// The transport is stream oriented (aka TCP or TLS) and the buffer passed
/// includes only the message header information from the message start line
/// up to and including the empty line terminating the header section. In this
/// case, the <see cref="Contents" /> property of the SIP message returned will
/// be set to <c>null</c> and <see cref="ContentLength" /> will be set to the
/// parsed value. The transport is then responsible for extracting the message
/// payload from the stream and explictly setting the <see cref="Contents" />
/// property.
/// </item>
/// </list>
/// </remarks>
public static SipMessage Parse(byte[] buffer, bool isCompletePacket)
{
string text;
int dataPos;
int p, pEnd, pColon;
string firstLine;
string line;
string reasonPhrase;
string[] fields;
SipMessage message;
SipHeader header;
int cbContents;
dataPos = Helper.IndexOf(buffer, CRLFCRLF);
if (dataPos == -1)
{
throw new SipException("Malformed SIP message: header termination missing.");
}
dataPos += 4;
text = Helper.FromUTF8(buffer, 0, dataPos);
// Look at the first line of text to determine whether we have a
// request or a response.
p = 0;
pEnd = text.IndexOf("\r\n");
firstLine = text.Substring(p, pEnd - p);
fields = firstLine.Split(' ');
if (fields.Length < 3)
{
throw new SipException("Malformed SIP message: invalid first line.");
}
p = firstLine.IndexOf(' ');
p = firstLine.IndexOf(' ', p + 1);
reasonPhrase = firstLine.Substring(p + 1);
if (fields[0].ToUpper().StartsWith("SIP/"))
{
int statusCode;
if (!int.TryParse(fields[1], out statusCode))
{
throw new SipException("Malformed SIP message: invalid response status code.");
}
if (statusCode < 100 || statusCode >= 700)
{
throw new SipException("Invalid status code [{0}].", statusCode);
}
message = new SipResponse(statusCode, reasonPhrase, fields[0]);
}
else
{
message = new SipRequest(fields[0], fields[1], reasonPhrase);
}
// Parse the headers
header = null;
p = pEnd + 2;
while (true)
{
pEnd = text.IndexOf("\r\n", p);
line = text.Substring(p, pEnd - p);
if (line.Length == 0)
{
break;
}
if (line[0] == ' ' || line[0] == '\t')
{
// Header folding
if (header == null)
{
throw new SipException("Malformed SIP message: invalid header folding.");
}
header.FullText += " " + line.Trim();
}
else
{
string name;
string value;
// Parse a normal header: <field-name> ":" <field-value>
pColon = line.IndexOf(':');
if (pColon == -1)
{
throw new SipException("Malformed SIP message: header missing a colon.");
}
name = line.Substring(0, pColon).Trim();
value = line.Substring(pColon + 1).Trim();
header = message.headers.Add(name, value);
}
p = pEnd + 2;
}
// Handle the payload
if (isCompletePacket)
{
// Extract the contents from the buffer. If we have a Content-Length header
// then use that to determine how much data we have, otherwise extract the
// data from the end of the headers to the end of the buffer.
header = message[SipHeader.ContentLength];
if (header != null)
{
if (!int.TryParse(header.Text, out cbContents) || cbContents < 0 || cbContents > buffer.Length - dataPos)
{
throw new SipException("Malformed SIP message: invalid Content-Length.");
}
message.contents = Helper.Extract(buffer, dataPos, cbContents);
}
else
{
message.contents = Helper.Extract(buffer, dataPos);
}
}
else
{
// Messages received from streaming transports must have a valid
// Content-Length header.
header = message[SipHeader.ContentLength];
if (header == null)
{
throw new SipException("Content-Length required for messages received on stream transports.");
}
if (!int.TryParse(header.Text, out cbContents) || cbContents < 0)
{
throw new SipException("Malformed SIP message: invalid Content-Length.");
}
}
return(message);
}
/// <summary>
/// The managing <see cref="ISipAgent" /> is responsible for calling this
/// method whenever it needs to send a response for the transaction.
/// </summary>
/// <param name="response">The <see cref="SipResponse" /> (or <c>null</c> to abort).</param>
/// <remarks>
/// You may pass <paramref name="response"/> as <c>null</c> to abort the transaction
/// without sending a response. This is equivalent to calling <see cref="Abort" />.
/// </remarks>
public void SendResponse(SipResponse response)
{
try
{
using (TimedLock.Lock(agent))
{
if (response == null)
{
// Handle aborting by transitioning to the completed state so
// request retransmits will continue to be absorbed by the
// transaction.
SetState(SipTransactionState.Completed);
return;
}
// Handle state specific processing
switch (base.State)
{
default:
case SipTransactionState.Unknown:
SysLog.LogError("Unexpected SIP transaction state.");
SetState(SipTransactionState.Terminated);
return;
case SipTransactionState.InviteCalling:
break;
case SipTransactionState.InviteProceeding:
if (response.IsProvisional)
{
// Provisional
provisionalResponse = response;
transport.Send(remoteEP, provisionalResponse);
return;
}
if (response.IsSuccess)
{
// Final response (success)
finalResponse = response;
transport.Send(remoteEP, finalResponse);
SetState(SipTransactionState.Terminated);
return;
}
// Final response (error)
finalResponse = response;
transport.Send(remoteEP, finalResponse);
SetState(SipTransactionState.InviteCompleted);
break;
case SipTransactionState.InviteCompleted:
break;
case SipTransactionState.InviteConfirmed:
break;
case SipTransactionState.Trying:
if (response.IsProvisional)
{
// Provisional
provisionalResponse = response;
transport.Send(remoteEP, provisionalResponse);
SetState(SipTransactionState.Proceeding);
return;
}
// Final response
finalResponse = response;
transport.Send(remoteEP, finalResponse);
SetState(SipTransactionState.Completed);
break;
case SipTransactionState.Proceeding:
if (response.IsProvisional)
{
// Provisional
provisionalResponse = response;
transport.Send(remoteEP, provisionalResponse);
return;
}
// Final response
finalResponse = response;
transport.Send(remoteEP, finalResponse);
SetState(SipTransactionState.Completed);
return;
case SipTransactionState.Completed:
break;
case SipTransactionState.Terminated:
break;
}
}
}
finally
{
}
}