ast_h323.cxx

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			cd->transfer_capability = ((unsigned int)capability & 0x1f) | (codingStandard << 5);
		else
			cd->transfer_capability = 0x00;	/* ITU coding of Speech */

		/* Don't show local username as called party name */
		SetDisplayName(cd->call_dest_e164);
	}

	/* Convert complex strings */
	//  FIXME: deal more than one source alias
	sourceAliases = setupPDU.GetSourceAliases();
	s1 = strdup((const char *)sourceAliases);
	if ((s = strchr(s1, ' ')) != NULL)
		*s = '\0';
	if ((s = strchr(s1, '\t')) != NULL)
		*s = '\0';
	cd->call_source_aliases = s1;

	destAliases = setupPDU.GetDestinationAlias();
	s1 = strdup((const char *)destAliases);
	if ((s = strchr(s1, ' ')) != NULL)
		*s = '\0';
	if ((s = strchr(s1, '\t')) != NULL)
		*s = '\0';
	cd->call_dest_alias = s1;
}

#ifdef TUNNELLING
static BOOL FetchInformationElements(Q931 &q931, const PBYTEArray &data)
{
	PINDEX offset = 0;

	while (offset < data.GetSize()) {
		// Get field discriminator
		int discriminator = data[offset++];

#if 0
		/* Do not overwrite existing IEs */
		if (q931.HasIE((Q931::InformationElementCodes)discriminator)) {
			if ((discriminatir & 0x80) == 0)
				offset += data[offset++];
			if (offset > data.GetSize())
				return FALSE;
			continue;
		}
#endif

		PBYTEArray * item = new PBYTEArray;

		// For discriminator with high bit set there is no data
		if ((discriminator & 0x80) == 0) {
			int len = data[offset++];

#if 0		// That is not H.225 but regular Q.931 (ISDN) IEs
			if (discriminator == UserUserIE) {
				// Special case of User-user field. See 7.2.2.31/H.225.0v4.
				len <<= 8;
				len |= data[offset++];

				// we also have a protocol discriminator, which we ignore
				offset++;

				// before decrementing the length, make sure it is not zero
				if (len == 0)
					return FALSE;

				// adjust for protocol discriminator
				len--;
			}
#endif

			if (offset + len > data.GetSize()) {
				delete item;
				return FALSE;
			}

			memcpy(item->GetPointer(len), (const BYTE *)data+offset, len);
			offset += len;
		}

		q931.SetIE((Q931::InformationElementCodes)discriminator, *item);
		delete item;
	}
	return TRUE;
}

static BOOL FetchCiscoTunneledInfo(Q931 &q931, const H323SignalPDU &pdu)
{
	BOOL res = FALSE;
	const H225_H323_UU_PDU &uuPDU = pdu.m_h323_uu_pdu;

	if(uuPDU.HasOptionalField(H225_H323_UU_PDU::e_nonStandardControl)) {
		for(int i = 0; i < uuPDU.m_nonStandardControl.GetSize(); ++i) {
			const H225_NonStandardParameter &np = uuPDU.m_nonStandardControl[i];
			const H225_NonStandardIdentifier &id = np.m_nonStandardIdentifier;
			if (id.GetTag() == H225_NonStandardIdentifier::e_h221NonStandard) {
				const H225_H221NonStandard &ni = id;
				/* Check for Cisco */
				if ((ni.m_t35CountryCode == 181) && (ni.m_t35Extension == 0) && (ni.m_manufacturerCode == 18)) {
					const PBYTEArray &data = np.m_data;
					if (h323debug)
						cout << setprecision(0) << "Received non-standard Cisco extension data " << np.m_data << endl;
					CISCO_H225_H323_UU_NonStdInfo c;
					PPER_Stream strm(data);
					if (c.Decode(strm)) {
						BOOL haveIEs = FALSE;
						if (h323debug)
							cout << setprecision(0) << "H323_UU_NonStdInfo = " << c << endl;
						if (c.HasOptionalField(CISCO_H225_H323_UU_NonStdInfo::e_protoParam)) {
							FetchInformationElements(q931, c.m_protoParam.m_qsigNonStdInfo.m_rawMesg);
							haveIEs = TRUE;
						}
						if (c.HasOptionalField(CISCO_H225_H323_UU_NonStdInfo::e_commonParam)) {
							FetchInformationElements(q931, c.m_commonParam.m_redirectIEinfo.m_redirectIE);
							haveIEs = TRUE;
						}
						if (haveIEs && h323debug)
							cout << setprecision(0) << "Information elements collected:" << q931 << endl;
						res = TRUE;
					} else {
						cout << "ERROR while decoding non-standard Cisco extension" << endl;
						return FALSE;
					}
				}
			}
		}
	}
	return res;
}

static BOOL EmbedCiscoTunneledInfo(H323SignalPDU &pdu)
{
	const static struct {
		Q931::InformationElementCodes ie;
		BOOL dontDelete;
	} codes[] = {
		{ Q931::RedirectingNumberIE, },
		{ Q931::FacilityIE, },
//		{ Q931::CallingPartyNumberIE, TRUE },
	};

	BOOL res = FALSE;
	BOOL notRedirOnly = FALSE;
	Q931 tmpQ931;
	Q931 &q931 = pdu.GetQ931();

	for(unsigned i = 0; i < ARRAY_LEN(codes); ++i) {
		if (q931.HasIE(codes[i].ie)) {
			tmpQ931.SetIE(codes[i].ie, q931.GetIE(codes[i].ie));
			if (!codes[i].dontDelete)
				q931.RemoveIE(codes[i].ie);
			if (codes[i].ie != Q931::RedirectingNumberIE)
				notRedirOnly = TRUE;
			res = TRUE;
		}
	}
	/* Have something to embed */
	if (res) {
		PBYTEArray msg;
		if (!tmpQ931.Encode(msg))
			return FALSE;
		PBYTEArray ies(msg.GetPointer() + 5, msg.GetSize() - 5);

		H225_H323_UU_PDU &uuPDU = pdu.m_h323_uu_pdu;
		if(!uuPDU.HasOptionalField(H225_H323_UU_PDU::e_nonStandardControl)) {
			uuPDU.IncludeOptionalField(H225_H323_UU_PDU::e_nonStandardControl);
			uuPDU.m_nonStandardControl.SetSize(0);
		}
		H225_NonStandardParameter *np = new H225_NonStandardParameter;
		uuPDU.m_nonStandardControl.Append(np);
		H225_NonStandardIdentifier &nsi = (*np).m_nonStandardIdentifier;
		nsi.SetTag(H225_NonStandardIdentifier::e_h221NonStandard);
		H225_H221NonStandard &ns = nsi;
		ns.m_t35CountryCode = 181;
		ns.m_t35Extension = 0;
		ns.m_manufacturerCode = 18;

		CISCO_H225_H323_UU_NonStdInfo c;
		c.IncludeOptionalField(CISCO_H225_H323_UU_NonStdInfo::e_version);
		c.m_version = 0;

		if (notRedirOnly) {
			c.IncludeOptionalField(CISCO_H225_H323_UU_NonStdInfo::e_protoParam);
			CISCO_H225_QsigNonStdInfo &qsigInfo = c.m_protoParam.m_qsigNonStdInfo;
			qsigInfo.m_iei = ies[0];
			qsigInfo.m_rawMesg = ies;
		} else {
			c.IncludeOptionalField(CISCO_H225_H323_UU_NonStdInfo::e_commonParam);
			c.m_commonParam.m_redirectIEinfo.m_redirectIE = ies;
		}
		PPER_Stream stream;
		c.Encode(stream);
		stream.CompleteEncoding();
		(*np).m_data = stream;
	}
	return res;
}

static const char OID_QSIG[] = "1.3.12.9";

static BOOL FetchQSIGTunneledInfo(Q931 &q931, const H323SignalPDU &pdu)
{
	BOOL res = FALSE;
	const H225_H323_UU_PDU &uuPDU = pdu.m_h323_uu_pdu;
	if (uuPDU.HasOptionalField(H225_H323_UU_PDU::e_tunnelledSignallingMessage)) {
		const H225_H323_UU_PDU_tunnelledSignallingMessage &sig = uuPDU.m_tunnelledSignallingMessage;
		const H225_TunnelledProtocol_id &proto = sig.m_tunnelledProtocolID.m_id;
		if ((proto.GetTag() == H225_TunnelledProtocol_id::e_tunnelledProtocolObjectID) &&
				(((const PASN_ObjectId &)proto).AsString() == OID_QSIG)) {
			const H225_ArrayOf_PASN_OctetString &sigs = sig.m_messageContent;
			for(int i = 0; i < sigs.GetSize(); ++i) {
				const PASN_OctetString &msg = sigs[i];
				if (h323debug)
					cout << setprecision(0) << "Q.931 message data is " << msg << endl;
				if(!q931.Decode((const PBYTEArray &)msg)) {
					cout << "Error while decoding Q.931 message" << endl;
					return FALSE;
				}
				res = TRUE;
				if (h323debug)
					cout << setprecision(0) << "Received QSIG message " << q931 << endl;
			}
		}
	}
	return res;
}

static H225_EndpointType *GetEndpointType(H323SignalPDU &pdu)
{
	if (!pdu.GetQ931().HasIE(Q931::UserUserIE))
		return NULL;

	H225_H323_UU_PDU_h323_message_body &body = pdu.m_h323_uu_pdu.m_h323_message_body;
	switch (body.GetTag()) {
	case H225_H323_UU_PDU_h323_message_body::e_setup:
		return &((H225_Setup_UUIE &)body).m_sourceInfo;
	case H225_H323_UU_PDU_h323_message_body::e_callProceeding:
		return &((H225_CallProceeding_UUIE &)body).m_destinationInfo;
	case H225_H323_UU_PDU_h323_message_body::e_connect:
		return &((H225_Connect_UUIE &)body).m_destinationInfo;
	case H225_H323_UU_PDU_h323_message_body::e_alerting:
		return &((H225_Alerting_UUIE &)body).m_destinationInfo;
	case H225_H323_UU_PDU_h323_message_body::e_facility:
		return &((H225_Facility_UUIE &)body).m_destinationInfo;
	case H225_H323_UU_PDU_h323_message_body::e_progress:
		return &((H225_Progress_UUIE &)body).m_destinationInfo;
	}
	return NULL;
}

static BOOL QSIGTunnelRequested(H323SignalPDU &pdu)
{
	H225_EndpointType *epType = GetEndpointType(pdu);
	if (epType) {
		if (!(*epType).HasOptionalField(H225_EndpointType::e_supportedTunnelledProtocols)) {
			return FALSE;
		}
		H225_ArrayOf_TunnelledProtocol &protos = (*epType).m_supportedTunnelledProtocols;
		for (int i = 0; i < protos.GetSize(); ++i)
		{
			if ((protos[i].GetTag() == H225_TunnelledProtocol_id::e_tunnelledProtocolObjectID) &&
					(((const PASN_ObjectId &)protos[i]).AsString() == OID_QSIG)) {
				return TRUE;
			}
		}
	}
	return FALSE;
}

static BOOL EmbedQSIGTunneledInfo(H323SignalPDU &pdu)
{
	const static Q931::InformationElementCodes codes[] =
	{ Q931::RedirectingNumberIE, Q931::FacilityIE };

	Q931 &q931 = pdu.GetQ931();
	PBYTEArray message;

	q931.Encode(message);

	/* Remove non-standard IEs */
	for(unsigned i = 0; i < ARRAY_LEN(codes); ++i) {
		if (q931.HasIE(codes[i])) {
			q931.RemoveIE(codes[i]);
		}
	}

	H225_H323_UU_PDU &uuPDU = pdu.m_h323_uu_pdu;
	H225_EndpointType *epType = GetEndpointType(pdu);
	if (epType) {
		if (!(*epType).HasOptionalField(H225_EndpointType::e_supportedTunnelledProtocols)) {
			(*epType).IncludeOptionalField(H225_EndpointType::e_supportedTunnelledProtocols);
			(*epType).m_supportedTunnelledProtocols.SetSize(0);
		}
		H225_ArrayOf_TunnelledProtocol &protos = (*epType).m_supportedTunnelledProtocols;
		BOOL addQSIG = TRUE;
		for (int i = 0; i < protos.GetSize(); ++i)
		{
			if ((protos[i].GetTag() == H225_TunnelledProtocol_id::e_tunnelledProtocolObjectID) &&
					(((PASN_ObjectId &)protos[i]).AsString() == OID_QSIG)) {
				addQSIG = FALSE;
				break;
			}
		}
		if (addQSIG) {
			H225_TunnelledProtocol *proto = new H225_TunnelledProtocol;
			(*proto).m_id.SetTag(H225_TunnelledProtocol_id::e_tunnelledProtocolObjectID);
			(PASN_ObjectId &)(proto->m_id) = OID_QSIG;
			protos.Append(proto);
		}
	}
	if (!uuPDU.HasOptionalField(H225_H323_UU_PDU::e_tunnelledSignallingMessage))
		uuPDU.IncludeOptionalField(H225_H323_UU_PDU::e_tunnelledSignallingMessage);
	H225_H323_UU_PDU_tunnelledSignallingMessage &sig = uuPDU.m_tunnelledSignallingMessage;
	H225_TunnelledProtocol_id &proto = sig.m_tunnelledProtocolID.m_id;
	if ((proto.GetTag() != H225_TunnelledProtocol_id::e_tunnelledProtocolObjectID) ||
			(((const PASN_ObjectId &)proto).AsString() != OID_QSIG)) {
		proto.SetTag(H225_TunnelledProtocol_id::e_tunnelledProtocolObjectID);
		(PASN_ObjectId &)proto = OID_QSIG;
		sig.m_messageContent.SetSize(0);
	}
	PASN_OctetString *msg = new PASN_OctetString;
	sig.m_messageContent.Append(msg);
	*msg = message;
	return TRUE;
}

BOOL MyH323Connection::EmbedTunneledInfo(H323SignalPDU &pdu)
{
	if ((tunnelOptions & H323_TUNNEL_QSIG) || (remoteTunnelOptions & H323_TUNNEL_QSIG))
		EmbedQSIGTunneledInfo(pdu);
	if ((tunnelOptions & H323_TUNNEL_CISCO) || (remoteTunnelOptions & H323_TUNNEL_CISCO))
		EmbedCiscoTunneledInfo(pdu);

	return TRUE;
}

/* Handle tunneled messages */
BOOL MyH323Connection::HandleSignalPDU(H323SignalPDU &pdu)
{
	if (pdu.GetQ931().HasIE(Q931::UserUserIE)) {
		Q931 tunneledInfo;
		const Q931 *q931Info;

		q931Info = NULL;
		if (FetchCiscoTunneledInfo(tunneledInfo, pdu)) {
			q931Info = &tunneledInfo;
			remoteTunnelOptions |= H323_TUNNEL_CISCO;
		}
		if (FetchQSIGTunneledInfo(tunneledInfo, pdu)) {
			q931Info = &tunneledInfo;
			remoteTunnelOptions |= H323_TUNNEL_QSIG;
		}
		if (!(remoteTunnelOptions & H323_TUNNEL_QSIG) && QSIGTunnelRequested(pdu)) {
			remoteTunnelOptions |= H323_TUNNEL_QSIG;
		}
		if (q931Info) {
			if (q931Info->HasIE(Q931::RedirectingNumberIE)) {
				pdu.GetQ931().SetIE(Q931::RedirectingNumberIE, q931Info->GetIE(Q931::RedirectingNumberIE));
				if (h323debug) {
					PString number;
					unsigned reason;
					if(q931Info->GetRedirectingNumber(number, NULL, NULL, NULL, NULL, &reason, 0, 0, 0))
						cout << "Got redirection from " << number << ", reason " << reason << endl;
				}
			}
		}
	}

	return H323Connection::HandleSignalPDU(pdu);
}
#endif

BOOL MyH323Connection::OnReceivedSignalSetup(const H323SignalPDU & setupPDU)
{
	call_details_t cd;

	if (h323debug) {
		cout << "\t--Received SETUP message" << endl;
	}

	if (connectionState == ShuttingDownConnection)
		return FALSE;

	SetCallDetails(&cd, setupPDU, TRUE);

	/* Notify Asterisk of the request */
	call_options_t *res = on_incoming_call(&cd);

	if (!res) {
		if (h323debug) {
			cout << "\t-- Call Failed" << endl;
		}
		return FALSE;
	}

	SetCallOptions(res, TRUE);

	/* Disable fastStart if requested by remote side */
	if (h245Tunneling && !setupPDU.m_h323_uu_pdu.m_h245Tunneling) {
		masterSlaveDeterminationProcedure->Stop();
		capabilityExchangeProcedure->Stop();
		PTRACE(3, "H225\tFast Start DISABLED!");
		h245Tunneling = FALSE;
	}

	return H323Connection::OnReceivedSignalSetup(setupPDU);
}

BOOL MyH323Connection::OnSendSignalSetup(H323SignalPDU & setupPDU)
{
	call_details_t cd;

	if (h323debug) {