You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
srsRAN_4G/srsepc/src/mme/s1ap_ctx_mngmt_proc.cc

303 lines
11 KiB
C++

/**
*
* \section COPYRIGHT
*
* Copyright 2013-2017 Software Radio Systems Limited
*
* \section LICENSE
*
* This file is part of srsLTE.
*
* srsLTE is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version.
*
* srsLTE is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* A copy of the GNU Affero General Public License can be found in
* the LICENSE file in the top-level directory of this distribution
* and at http://www.gnu.org/licenses/.
*
*/
//#include "srslte/upper/s1ap_common.h"
#include "srslte/common/bcd_helpers.h"
#include "mme/s1ap.h"
#include "mme/s1ap_ctx_mngmt_proc.h"
#include "srslte/common/liblte_security.h"
namespace srsepc{
s1ap_ctx_mngmt_proc* s1ap_ctx_mngmt_proc::m_instance = NULL;
boost::mutex s1ap_ctx_mngmt_proc_instance_mutex;
s1ap_ctx_mngmt_proc::s1ap_ctx_mngmt_proc()
{
}
s1ap_ctx_mngmt_proc::~s1ap_ctx_mngmt_proc()
{
}
s1ap_ctx_mngmt_proc*
s1ap_ctx_mngmt_proc::get_instance(void)
{
boost::mutex::scoped_lock lock(s1ap_ctx_mngmt_proc_instance_mutex);
if(NULL == m_instance) {
m_instance = new s1ap_ctx_mngmt_proc();
}
return(m_instance);
}
void
s1ap_ctx_mngmt_proc::cleanup(void)
{
boost::mutex::scoped_lock lock(s1ap_ctx_mngmt_proc_instance_mutex);
if(NULL != m_instance) {
delete m_instance;
m_instance = NULL;
}
}
void
s1ap_ctx_mngmt_proc::init(void)
{
m_s1ap = s1ap::get_instance();
m_mme_gtpc = mme_gtpc::get_instance();
m_s1ap_log = m_s1ap->m_s1ap_log;
m_s1ap_args = m_s1ap->m_s1ap_args;
m_pool = srslte::byte_buffer_pool::get_instance();
m_s1ap_nas_transport = s1ap_nas_transport::get_instance();
}
bool
s1ap_ctx_mngmt_proc::send_initial_context_setup_request(uint32_t mme_ue_s1ap_id, struct srslte::gtpc_create_session_response *cs_resp, struct srslte::gtpc_f_teid_ie sgw_ctrl_fteid)
{
int s1mme = m_s1ap->get_s1_mme();
//Prepare reply PDU
LIBLTE_S1AP_S1AP_PDU_STRUCT pdu;
bzero(&pdu, sizeof(LIBLTE_S1AP_S1AP_PDU_STRUCT));
pdu.choice_type = LIBLTE_S1AP_S1AP_PDU_CHOICE_INITIATINGMESSAGE;
LIBLTE_S1AP_INITIATINGMESSAGE_STRUCT *init = &pdu.choice.initiatingMessage;
init->procedureCode = LIBLTE_S1AP_PROC_ID_INITIALCONTEXTSETUP;
init->choice_type = LIBLTE_S1AP_INITIATINGMESSAGE_CHOICE_INITIALCONTEXTSETUPREQUEST;
LIBLTE_S1AP_MESSAGE_INITIALCONTEXTSETUPREQUEST_STRUCT *in_ctxt_req = &init->choice.InitialContextSetupRequest;
LIBLTE_S1AP_E_RABTOBESETUPITEMCTXTSUREQ_STRUCT *erab_ctxt = &in_ctxt_req->E_RABToBeSetupListCtxtSUReq.buffer[0]; //FIXME support more than one erab
srslte::byte_buffer_t *reply_buffer = m_pool->allocate();
m_s1ap_log->info("Preparing to send Initial Context Setup request\n");
//Find UE Context
ue_ctx_t *ue_ctx = m_s1ap->find_ue_ctx(mme_ue_s1ap_id);
if(ue_ctx == NULL)
{
m_s1ap_log->error("Could not find UE to send Setup Context Request. MME S1AP Id: %d", mme_ue_s1ap_id);
return false;
}
//Add MME and eNB S1AP Ids
in_ctxt_req->MME_UE_S1AP_ID.MME_UE_S1AP_ID = ue_ctx->mme_ue_s1ap_id;
in_ctxt_req->eNB_UE_S1AP_ID.ENB_UE_S1AP_ID = ue_ctx->enb_ue_s1ap_id;
//Set UE-AMBR
in_ctxt_req->uEaggregateMaximumBitrate.uEaggregateMaximumBitRateDL.BitRate=1000000000;//2^32-1
in_ctxt_req->uEaggregateMaximumBitrate.uEaggregateMaximumBitRateUL.BitRate=1000000000;//FIXME Get UE-AMBR from HSS
//Setup eRAB context
in_ctxt_req->E_RABToBeSetupListCtxtSUReq.len = 1;
erab_ctxt->e_RAB_ID.E_RAB_ID = cs_resp->eps_bearer_context_created.ebi;
//Setup E-RAB QoS parameters
erab_ctxt->e_RABlevelQoSParameters.qCI.QCI = 9;
erab_ctxt->e_RABlevelQoSParameters.allocationRetentionPriority.priorityLevel.PriorityLevel = 15 ;//Lowest
erab_ctxt->e_RABlevelQoSParameters.allocationRetentionPriority.pre_emptionCapability = LIBLTE_S1AP_PRE_EMPTIONCAPABILITY_SHALL_NOT_TRIGGER_PRE_EMPTION;
erab_ctxt->e_RABlevelQoSParameters.allocationRetentionPriority.pre_emptionVulnerability = LIBLTE_S1AP_PRE_EMPTIONVULNERABILITY_PRE_EMPTABLE;
erab_ctxt->e_RABlevelQoSParameters.gbrQosInformation_present=false;
//Set E-RAB S-GW F-TEID
if (cs_resp->eps_bearer_context_created.s1_u_sgw_f_teid_present == false){
m_s1ap_log->error("Did not receive S1-U TEID in create session response\n");
return false;
}
erab_ctxt->transportLayerAddress.n_bits = 32; //IPv4
uint32_t sgw_s1u_ip = htonl(cs_resp->eps_bearer_context_created.s1_u_sgw_f_teid.ipv4);
//uint32_t sgw_s1u_ip = cs_resp->eps_bearer_context_created.s1_u_sgw_f_teid.ipv4;
uint8_t *tmp_ptr = erab_ctxt->transportLayerAddress.buffer;
liblte_value_2_bits(sgw_s1u_ip, &tmp_ptr, 32);//FIXME consider ipv6
uint32_t tmp_teid = cs_resp->eps_bearer_context_created.s1_u_sgw_f_teid.teid;
memcpy(erab_ctxt->gTP_TEID.buffer, &tmp_teid, sizeof(uint32_t));
//Set UE security capabilities and k_enb
bzero(in_ctxt_req->UESecurityCapabilities.encryptionAlgorithms.buffer,sizeof(uint8_t)*16);
bzero(in_ctxt_req->UESecurityCapabilities.integrityProtectionAlgorithms.buffer,sizeof(uint8_t)*16);
for(int i = 0; i<3; i++)
{
if(ue_ctx->ue_network_cap.eea[i+1] == true)
{
in_ctxt_req->UESecurityCapabilities.encryptionAlgorithms.buffer[i] = 1; //EEA supported
}
else
{
in_ctxt_req->UESecurityCapabilities.encryptionAlgorithms.buffer[i] = 0; //EEA not supported
}
if(ue_ctx->ue_network_cap.eia[i+1] == true)
{
in_ctxt_req->UESecurityCapabilities.integrityProtectionAlgorithms.buffer[i] = 1; //EEA supported
}
else
{
in_ctxt_req->UESecurityCapabilities.integrityProtectionAlgorithms.buffer[i] = 0; //EEA not supported
}
// in_ctxt_req->UESecurityCapabilities.integrityProtectionAlgorithms.buffer[0] = 1; //EIA1
}
uint8_t key_enb[32];
liblte_security_generate_k_enb(ue_ctx->security_ctxt.k_asme, ue_ctx->security_ctxt.ul_nas_count, key_enb);
liblte_unpack(key_enb, 32, in_ctxt_req->SecurityKey.buffer);
m_s1ap_log->info("Generating KeNB with UL NAS COUNT: %d\n",ue_ctx->security_ctxt.ul_nas_count);
//Set Attach accepted and activat default bearer NAS messages
if(cs_resp->paa_present != true)
{
m_s1ap_log->error("PAA not present\n");
return false;
}
if(cs_resp->paa.pdn_type != srslte::GTPC_PDN_TYPE_IPV4)
{
m_s1ap_log->error("IPv6 not supported yet\n");
return false;
}
srslte::byte_buffer_t *nas_buffer = m_pool->allocate();
m_s1ap_nas_transport->pack_attach_accept(ue_ctx, erab_ctxt, &cs_resp->paa, nas_buffer);
LIBLTE_ERROR_ENUM err = liblte_s1ap_pack_s1ap_pdu(&pdu, (LIBLTE_BYTE_MSG_STRUCT*)reply_buffer);
if(err != LIBLTE_SUCCESS)
{
m_s1ap_log->error("Could not pack Initial Context Setup Request Message\n");
return false;
}
//Send Reply to eNB
ssize_t n_sent = sctp_send(s1mme,reply_buffer->msg, reply_buffer->N_bytes, &ue_ctx->enb_sri, 0);
if(n_sent == -1)
{
m_s1ap_log->error("Failed to send Initial Context Setup Request\n");
return false;
}
//Change E-RAB state to Context Setup Requested and save S-GW control F-TEID
ue_ctx->erabs_ctx[erab_ctxt->e_RAB_ID.E_RAB_ID].state = ERAB_CTX_REQUESTED;
ue_ctx->erabs_ctx[erab_ctxt->e_RAB_ID.E_RAB_ID].sgw_ctrl_fteid.teid = sgw_ctrl_fteid.teid;
ue_ctx->erabs_ctx[erab_ctxt->e_RAB_ID.E_RAB_ID].sgw_ctrl_fteid.ipv4 = sgw_ctrl_fteid.ipv4;
struct in_addr addr;
addr.s_addr = sgw_s1u_ip;
m_s1ap_log->info("Sent Intial Context Setup Request. E-RAB id %d \n",erab_ctxt->e_RAB_ID.E_RAB_ID);
m_s1ap_log->info("Initial Context -- S1-U TEID 0x%x. IP %s \n", tmp_teid,inet_ntoa(addr));
m_s1ap_log->console("Sent Intial Context Setup Request, E-RAB id %d\n",erab_ctxt->e_RAB_ID.E_RAB_ID);
m_s1ap_log->console("Initial Context -- S1-U TEID 0x%x. IP %s \n", tmp_teid,inet_ntoa(addr));
m_pool->deallocate(reply_buffer);
m_pool->deallocate(nas_buffer);
return true;
}
bool
s1ap_ctx_mngmt_proc::handle_initial_context_setup_response(LIBLTE_S1AP_MESSAGE_INITIALCONTEXTSETUPRESPONSE_STRUCT *in_ctxt_resp)
{
uint32_t mme_ue_s1ap_id = in_ctxt_resp->MME_UE_S1AP_ID.MME_UE_S1AP_ID;
ue_ctx_t *ue_ctx = m_s1ap->find_ue_ctx(mme_ue_s1ap_id);
if (ue_ctx == NULL)
{
m_s1ap_log->error("Could not find UE's context in active UE's map\n");
return false;
}
//Setup E-RABs
for(uint32_t i=0; i<in_ctxt_resp->E_RABSetupListCtxtSURes.len;i++)
{
uint8_t erab_id = in_ctxt_resp->E_RABSetupListCtxtSURes.buffer[i].e_RAB_ID.E_RAB_ID;
erab_ctx_t *erab_ctx = &ue_ctx->erabs_ctx[erab_id];
if (erab_ctx->state != ERAB_CTX_REQUESTED)
{
m_s1ap_log->error("E-RAB requested was not active %d\n",erab_id);
return false;
}
//Mark E-RAB with context setup
erab_ctx->state = ERAB_CTX_SETUP;
//Set the GTP information
uint8_t *bit_ptr = in_ctxt_resp->E_RABSetupListCtxtSURes.buffer[i].transportLayerAddress.buffer;
erab_ctx->enb_fteid.ipv4 = htonl(liblte_bits_2_value(&bit_ptr,32));
memcpy(&erab_ctx->enb_fteid.teid, in_ctxt_resp->E_RABSetupListCtxtSURes.buffer[i].gTP_TEID.buffer, 4);
erab_ctx->enb_fteid.teid = ntohl(erab_ctx->enb_fteid.teid);
char enb_addr_str[INET_ADDRSTRLEN+1];
const char *err = inet_ntop(AF_INET, &erab_ctx->enb_fteid.ipv4,enb_addr_str,sizeof(enb_addr_str));
if(err == NULL)
{
m_s1ap_log->error("Error converting IP to string\n");
}
m_s1ap_log->info("E-RAB Context Setup. E-RAB id %d\n",erab_ctx->erab_id);
m_s1ap_log->info("E-RAB Context -- eNB TEID 0x%x, eNB Address %s\n", erab_ctx->enb_fteid.teid, enb_addr_str);
m_s1ap_log->console("E-RAB Context Setup. E-RAB id %d\n",erab_ctx->erab_id);
m_s1ap_log->console("E-RAB Context -- eNB TEID 0x%x; eNB GTP-U Address %s\n", erab_ctx->enb_fteid.teid, enb_addr_str);
}
return true;
}
bool
s1ap_ctx_mngmt_proc::handle_ue_context_release_request(LIBLTE_S1AP_MESSAGE_UECONTEXTRELEASEREQUEST_STRUCT *ue_rel, struct sctp_sndrcvinfo *enb_sri, srslte::byte_buffer_t *reply_buffer, bool *reply_flag)
{
uint32_t mme_ue_s1ap_id = ue_rel->MME_UE_S1AP_ID.MME_UE_S1AP_ID;
m_s1ap_log->info("Received UE Context Release Request. MME-UE S1AP Id: %d\n", mme_ue_s1ap_id);
m_s1ap_log->console("Received UE Context Release Request. MME-UE S1AP Id %d\n", mme_ue_s1ap_id);
ue_ctx_t *ue_ctx = m_s1ap->find_ue_ctx(mme_ue_s1ap_id);
if(ue_ctx == NULL)
{
m_s1ap_log->info("UE not found. MME-UE S1AP Id: %d\n", mme_ue_s1ap_id);
return false;
}
//Delete any context at the SPGW
bool active = false;
for(int i=0;i<MAX_ERABS_PER_UE;i++)
{
if(ue_ctx->erabs_ctx[i].state != ERAB_DEACTIVATED)
{
active = true;
//ue_ctx->erabs_ctx[i].state = ERAB_DEACTIVATED;
break;
}
}
if(active == true)
{
//There are active E-RABs, send delete session request
m_mme_gtpc->send_delete_session_request(ue_ctx);
}
//m_s1ap->delete_ue_ctx(ue_ctx);
for(int i=0;i<MAX_ERABS_PER_UE;i++)
{
ue_ctx->erabs_ctx[i].state = ERAB_DEACTIVATED;
}
//Delete UE context
m_s1ap_log->info("Deleted UE Context.\n");
return true;
}
} //namespace srsepc