Files
ueransim/src/gnb/ngap/session.cpp
2025-08-12 14:15:27 +08:00

316 lines
13 KiB
C++

//
// This file is a part of UERANSIM project.
// Copyright (c) 2023 ALİ GÜNGÖR.
//
// https://github.com/aligungr/UERANSIM/
// See README, LICENSE, and CONTRIBUTING files for licensing details.
//
#include "encode.hpp"
#include "task.hpp"
#include "utils.hpp"
#include <set>
#include <stdexcept>
#include <gnb/gtp/task.hpp>
#include <asn/ngap/ASN_NGAP_AssociatedQosFlowItem.h>
#include <asn/ngap/ASN_NGAP_AssociatedQosFlowList.h>
#include <asn/ngap/ASN_NGAP_GTPTunnel.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceFailedToSetupItemSURes.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceReleaseCommand.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceReleaseResponse.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceReleaseResponseTransfer.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceReleasedItemRelRes.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceSetupItemSUReq.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceSetupItemSURes.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceSetupRequest.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceSetupRequestTransfer.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceSetupResponse.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceSetupResponseTransfer.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceSetupUnsuccessfulTransfer.h>
#include <asn/ngap/ASN_NGAP_PDUSessionResourceToReleaseItemRelCmd.h>
#include <asn/ngap/ASN_NGAP_ProtocolIE-Field.h>
#include <asn/ngap/ASN_NGAP_QosFlowPerTNLInformationItem.h>
#include <asn/ngap/ASN_NGAP_QosFlowPerTNLInformationList.h>
#include <asn/ngap/ASN_NGAP_QosFlowSetupRequestItem.h>
#include <asn/ngap/ASN_NGAP_QosFlowSetupRequestList.h>
namespace nr::gnb
{
void NgapTask::receiveSessionResourceSetupRequest(int amfId, ASN_NGAP_PDUSessionResourceSetupRequest *msg)
{
std::vector<ASN_NGAP_PDUSessionResourceSetupItemSURes *> successList;
std::vector<ASN_NGAP_PDUSessionResourceFailedToSetupItemSURes *> failedList;
auto *ue = findUeByNgapIdPair(amfId, ngap_utils::FindNgapIdPair(msg));
if (ue == nullptr)
return;
auto *ieList = asn::ngap::GetProtocolIe(msg, ASN_NGAP_ProtocolIE_ID_id_PDUSessionResourceSetupListSUReq);
if (ieList)
{
auto &list = ieList->PDUSessionResourceSetupListSUReq.list;
for (int i = 0; i < list.count; i++)
{
auto &item = list.array[i];
auto *transfer = ngap_encode::Decode<ASN_NGAP_PDUSessionResourceSetupRequestTransfer>(
asn_DEF_ASN_NGAP_PDUSessionResourceSetupRequestTransfer, item->pDUSessionResourceSetupRequestTransfer);
if (transfer == nullptr)
{
m_logger->err(
"Unable to decode a PDU session resource setup request transfer. Ignoring the relevant item");
asn::Free(asn_DEF_ASN_NGAP_PDUSessionResourceSetupRequestTransfer, transfer);
continue;
}
auto *resource = new PduSessionResource(ue->ctxId, static_cast<int>(item->pDUSessionID));
auto *ie = asn::ngap::GetProtocolIe(transfer, ASN_NGAP_ProtocolIE_ID_id_PDUSessionAggregateMaximumBitRate);
if (ie)
{
resource->sessionAmbr.dlAmbr =
asn::GetUnsigned64(ie->PDUSessionAggregateMaximumBitRate.pDUSessionAggregateMaximumBitRateDL) /
8ull;
resource->sessionAmbr.ulAmbr =
asn::GetUnsigned64(ie->PDUSessionAggregateMaximumBitRate.pDUSessionAggregateMaximumBitRateUL) /
8ull;
}
ie = asn::ngap::GetProtocolIe(transfer, ASN_NGAP_ProtocolIE_ID_id_DataForwardingNotPossible);
if (ie)
resource->dataForwardingNotPossible = true;
ie = asn::ngap::GetProtocolIe(transfer, ASN_NGAP_ProtocolIE_ID_id_PDUSessionType);
if (ie)
resource->sessionType = ngap_utils::PduSessionTypeFromAsn(ie->PDUSessionType);
ie = asn::ngap::GetProtocolIe(transfer, ASN_NGAP_ProtocolIE_ID_id_UL_NGU_UP_TNLInformation);
if (ie)
{
resource->upTunnel.teid =
(uint32_t)asn::GetOctet4(ie->UPTransportLayerInformation.choice.gTPTunnel->gTP_TEID);
resource->upTunnel.address =
asn::GetOctetString(ie->UPTransportLayerInformation.choice.gTPTunnel->transportLayerAddress);
}
ie = asn::ngap::GetProtocolIe(transfer, ASN_NGAP_ProtocolIE_ID_id_QosFlowSetupRequestList);
if (ie)
{
auto *ptr = asn::New<ASN_NGAP_QosFlowSetupRequestList>();
asn::DeepCopy(asn_DEF_ASN_NGAP_QosFlowSetupRequestList, ie->QosFlowSetupRequestList, ptr);
resource->qosFlows = asn::WrapUnique(ptr, asn_DEF_ASN_NGAP_QosFlowSetupRequestList);
}
auto error = setupPduSessionResource(ue, resource);
if (error.has_value())
{
auto *tr = asn::New<ASN_NGAP_PDUSessionResourceSetupUnsuccessfulTransfer>();
ngap_utils::ToCauseAsn_Ref(error.value(), tr->cause);
OctetString encodedTr =
ngap_encode::EncodeS(asn_DEF_ASN_NGAP_PDUSessionResourceSetupUnsuccessfulTransfer, tr);
if (encodedTr.length() == 0)
throw std::runtime_error("PDUSessionResourceSetupUnsuccessfulTransfer encoding failed");
asn::Free(asn_DEF_ASN_NGAP_PDUSessionResourceSetupUnsuccessfulTransfer, tr);
auto *res = asn::New<ASN_NGAP_PDUSessionResourceFailedToSetupItemSURes>();
res->pDUSessionID = resource->psi;
asn::SetOctetString(res->pDUSessionResourceSetupUnsuccessfulTransfer, encodedTr);
failedList.push_back(res);
}
else
{
if (item->pDUSessionNAS_PDU)
deliverDownlinkNas(ue->ctxId, asn::GetOctetString(*item->pDUSessionNAS_PDU));
auto *tr = asn::New<ASN_NGAP_PDUSessionResourceSetupResponseTransfer>();
auto &qosList = resource->qosFlows->list;
for (int iQos = 0; iQos < qosList.count; iQos++)
{
auto *associatedQosFlowItem = asn::New<ASN_NGAP_AssociatedQosFlowItem>();
associatedQosFlowItem->qosFlowIdentifier = qosList.array[iQos]->qosFlowIdentifier;
asn::SequenceAdd(tr->dLQosFlowPerTNLInformation.associatedQosFlowList, associatedQosFlowItem);
}
auto &upInfo = tr->dLQosFlowPerTNLInformation.uPTransportLayerInformation;
upInfo.present = ASN_NGAP_UPTransportLayerInformation_PR_gTPTunnel;
upInfo.choice.gTPTunnel = asn::New<ASN_NGAP_GTPTunnel>();
asn::SetBitString(upInfo.choice.gTPTunnel->transportLayerAddress, resource->downTunnel.address);
asn::SetOctetString4(upInfo.choice.gTPTunnel->gTP_TEID, (octet4)resource->downTunnel.teid);
OctetString encodedTr =
ngap_encode::EncodeS(asn_DEF_ASN_NGAP_PDUSessionResourceSetupResponseTransfer, tr);
if (encodedTr.length() == 0)
throw std::runtime_error("PDUSessionResourceSetupResponseTransfer encoding failed");
asn::Free(asn_DEF_ASN_NGAP_PDUSessionResourceSetupResponseTransfer, tr);
auto *res = asn::New<ASN_NGAP_PDUSessionResourceSetupItemSURes>();
res->pDUSessionID = resource->psi;
asn::SetOctetString(res->pDUSessionResourceSetupResponseTransfer, encodedTr);
successList.push_back(res);
}
asn::Free(asn_DEF_ASN_NGAP_PDUSessionResourceSetupRequestTransfer, transfer);
}
}
auto *ieNasPdu = asn::ngap::GetProtocolIe(msg, ASN_NGAP_ProtocolIE_ID_id_NAS_PDU);
if (ieNasPdu)
deliverDownlinkNas(ue->ctxId, asn::GetOctetString(ieNasPdu->NAS_PDU));
std::vector<ASN_NGAP_PDUSessionResourceSetupResponseIEs *> responseIes;
if (!successList.empty())
{
auto *ie = asn::New<ASN_NGAP_PDUSessionResourceSetupResponseIEs>();
ie->id = ASN_NGAP_ProtocolIE_ID_id_PDUSessionResourceSetupListSURes;
ie->criticality = ASN_NGAP_Criticality_ignore;
ie->value.present = ASN_NGAP_PDUSessionResourceSetupResponseIEs__value_PR_PDUSessionResourceSetupListSURes;
for (auto &item : successList)
asn::SequenceAdd(ie->value.choice.PDUSessionResourceSetupListSURes, item);
responseIes.push_back(ie);
}
if (!failedList.empty())
{
auto *ie = asn::New<ASN_NGAP_PDUSessionResourceSetupResponseIEs>();
ie->id = ASN_NGAP_ProtocolIE_ID_id_PDUSessionResourceFailedToSetupListSURes;
ie->criticality = ASN_NGAP_Criticality_ignore;
ie->value.present =
ASN_NGAP_PDUSessionResourceSetupResponseIEs__value_PR_PDUSessionResourceFailedToSetupListSURes;
for (auto &item : failedList)
asn::SequenceAdd(ie->value.choice.PDUSessionResourceFailedToSetupListSURes, item);
responseIes.push_back(ie);
}
auto *respPdu = asn::ngap::NewMessagePdu<ASN_NGAP_PDUSessionResourceSetupResponse>(responseIes);
sendNgapUeAssociated(ue->ctxId, respPdu);
if (failedList.empty())
m_logger->info("PDU session resource(s) setup for UE[%d] count[%d]", ue->ctxId,
static_cast<int>(successList.size()));
else if (successList.empty())
m_logger->err("PDU session resource(s) setup was failed for UE[%d] count[%d]", ue->ctxId,
static_cast<int>(failedList.size()));
else
m_logger->err("PDU session establishment is partially successful for UE[%d], success[%d], failed[%d]",
static_cast<int>(successList.size()), static_cast<int>(failedList.size()));
}
std::optional<NgapCause> NgapTask::setupPduSessionResource(NgapUeContext *ue, PduSessionResource *resource)
{
if (resource->sessionType != PduSessionType::IPv4)
{
m_logger->err("PDU session resource could not setup: Only IPv4 is supported");
return NgapCause::RadioNetwork_unspecified;
}
if (resource->upTunnel.address.length() == 0)
{
m_logger->err("PDU session resource could not setup: Uplink TNL information is missing");
return NgapCause::Protocol_transfer_syntax_error;
}
if (resource->qosFlows == nullptr || resource->qosFlows->list.count == 0)
{
m_logger->err("PDU session resource could not setup: QoS flow list is null or empty");
return NgapCause::Protocol_semantic_error;
}
std::string gtpIp = m_base->config->gtpAdvertiseIp.value_or(m_base->config->gtpIp);
resource->downTunnel.address = utils::IpToOctetString(gtpIp);
resource->downTunnel.teid = ++m_downlinkTeidCounter;
auto w = std::make_unique<NmGnbNgapToGtp>(NmGnbNgapToGtp::SESSION_CREATE);
w->resource = resource;
m_base->gtpTask->push(std::move(w));
ue->pduSessions.insert(resource->psi);
return {};
}
void NgapTask::receiveSessionResourceReleaseCommand(int amfId, ASN_NGAP_PDUSessionResourceReleaseCommand *msg)
{
auto *ue = findUeByNgapIdPair(amfId, ngap_utils::FindNgapIdPair(msg));
if (ue == nullptr)
return;
std::set<int> psIds{};
auto *ieReq = asn::ngap::GetProtocolIe(msg, ASN_NGAP_ProtocolIE_ID_id_PDUSessionResourceToReleaseListRelCmd);
if (ieReq)
{
auto &list = ieReq->PDUSessionResourceToReleaseListRelCmd.list;
for (int i = 0; i < list.count; i++)
{
auto &item = list.array[i];
if (item)
psIds.insert(static_cast<int>(item->pDUSessionID));
}
}
ieReq = asn::ngap::GetProtocolIe(msg, ASN_NGAP_ProtocolIE_ID_id_NAS_PDU);
if (ieReq)
deliverDownlinkNas(ue->ctxId, asn::GetOctetString(ieReq->NAS_PDU));
auto *ieResp = asn::New<ASN_NGAP_PDUSessionResourceReleaseResponseIEs>();
ieResp->id = ASN_NGAP_ProtocolIE_ID_id_PDUSessionResourceReleasedListRelRes;
ieResp->criticality = ASN_NGAP_Criticality_ignore;
ieResp->value.present =
ASN_NGAP_PDUSessionResourceReleaseResponseIEs__value_PR_PDUSessionResourceReleasedListRelRes;
// Perform release
for (auto &psi : psIds)
{
auto w = std::make_unique<NmGnbNgapToGtp>(NmGnbNgapToGtp::SESSION_RELEASE);
w->ueId = ue->ctxId;
w->psi = psi;
m_base->gtpTask->push(std::move(w));
ue->pduSessions.erase(psi);
}
for (auto &psi : psIds)
{
auto *tr = asn::New<ASN_NGAP_PDUSessionResourceReleaseResponseTransfer>();
OctetString encodedTr = ngap_encode::EncodeS(asn_DEF_ASN_NGAP_PDUSessionResourceReleaseResponseTransfer, tr);
if (encodedTr.length() == 0)
throw std::runtime_error("PDUSessionResourceReleaseResponseTransfer encoding failed");
asn::Free(asn_DEF_ASN_NGAP_PDUSessionResourceReleaseResponseTransfer, tr);
auto *item = asn::New<ASN_NGAP_PDUSessionResourceReleasedItemRelRes>();
item->pDUSessionID = static_cast<ASN_NGAP_PDUSessionID_t>(psi);
asn::SetOctetString(item->pDUSessionResourceReleaseResponseTransfer, encodedTr);
asn::SequenceAdd(ieResp->value.choice.PDUSessionResourceReleasedListRelRes, item);
}
auto *respPdu = asn::ngap::NewMessagePdu<ASN_NGAP_PDUSessionResourceReleaseResponse>({ieResp});
sendNgapUeAssociated(ue->ctxId, respPdu);
m_logger->info("PDU session resource(s) released for UE[%d] count[%d]", ue->ctxId, static_cast<int>(psIds.size()));
}
} // namespace nr::gnb