vrr/open5gs
2
0
Fork 0
mirror of https://github.com/open5gs/open5gs.git synced 2026-04-28 03:19:31 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 2
open5gs/lib/gtp/xact.h
Sukchan Lee fd897f35a3 MME: handle EPS Bearer Context Status mismatch when active_flag=0 (#4112) 
When the UE sends a Tracking Area Update (TAU) Request with active_flag=0,
the MME previously sent TAU Accept without verifying the EPS Bearer Context
Status (EBCS). This caused stale bearer sessions to remain in the MME even
if the UE had already released them.

According to 3GPP TS 24.301 §5.5.3.2, the MME should release any bearer
not reported in the UE’s EBCS when active_flag=0. This patch introduces
mme_send_delete_session_or_tau_accept(), which compares the UE’s EBCS bitmask
with the MME session list and deletes any missing default bearer session
before sending TAU Accept.

If no mismatch is found, TAU Accept is sent immediately. The Delete Session
response triggers TAU Accept when deletions are required. This ensures that
the TAU Accept message reflects the UE’s current bearer context accurately.

Also includes:
 - Added OGS_GTP_DELETE_SEND_TAU_ACCEPT handling in mme-s11-handler.c
 - Simplified EBCS structure (uint16_t value) for bitmask comparison
 - Updated TAU-related tests with realistic EBI bitmasks (0x20, 0x60)

This change aligns TAU handling with 3GPP 24.301 and prevents bearer
mismatch issues between UE and EPC during TAU.
2025-10-16 21:46:38 +09:00

193 lines
7.5 KiB
C
Raw Blame History

/*
* Copyright (C) 2019 by Sukchan Lee <acetcom@gmail.com>
* Copyright (C) 2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
* Copyright (C) 2023 by Sukchan Lee <acetcom@gmail.com>
*
* This file is part of Open5GS.
*
* This program 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.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#if !defined(OGS_GTP_INSIDE) && !defined(OGS_GTP_COMPILATION)
#error "This header cannot be included directly."
#endif
#ifndef OGS_GTP_XACT_H
#define OGS_GTP_XACT_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* p225-226 Chapter 7.6 in TS 29.274 V15.9.0
*
* A Sequence Number used for a Command message shall have the most significant
* bit set to 1. A Sequence Number in a message, which was triggered by
* a Command message, as well as respective Triggered Reply message
* shall have the same Sequence Number as the Command message
* (i.e. shall also have the most significant bit set to 1).
*
* This setting of the most significant bit of the Sequence Number is done
* to avoid potential clashes between the Sequence Number selected for
* a Command message, and the Sequence Number selected by a GTPv2 peer
* for a Request message, which was not triggered by a Command message.
*
* A Sequence Number used for a Request message, which was not triggered
* by a Command message shall have the most significant bit set to 0.
*/
#define OGS_GTP_MIN_XACT_ID 1
#define OGS_GTP_CMD_XACT_ID 0x800000
#define OGS_GTP1_MIN_XACT_ID 0
#define OGS_GTP1_MAX_XACT_ID 65535
/**
* Transaction context
*/
typedef struct ogs_gtp_xact_s {
ogs_lnode_t node; /**< A node of list */
ogs_pool_id_t id;
/*
* Issues #3240
*
* SMF->SGW-C->MME: First Update Bearer Request
* MME->UE: First Modify EPS bearer context request
* SMF->SGW-C->MME: Second Update Bearer Request
* MME->UE: Second Modify EPS bearer context request
* UE->MME: First Modify EPS bearer context accept
* MME->SGW-C->SMF: First Update Bearer Response
* UE->MME: Second Modify EPS bearer context accept
* MME->SGW-C->SMF: Second Update Bearer Response
*
* In the above situation, while NAS-ESM messages are exchanged
* between the MME and UE, the bearer may have multiple transactions
* that need to be managed. to_update_node is used as a node
* in the Transaction List related to Update Bearer Request/Response.
*/
ogs_lnode_t to_update_node;
ogs_pool_id_t index;
uint8_t gtp_version; /**< 1 or 2 */
#define OGS_GTP_LOCAL_ORIGINATOR 0
#define OGS_GTP_REMOTE_ORIGINATOR 1
uint8_t org; /**< Transaction' originator.
local or remote */
uint32_t xid; /**< Transaction ID */
ogs_gtp_node_t *gnode; /**< Relevant GTP node context */
void (*cb)(ogs_gtp_xact_t *, void *); /**< Local timer expiration handler */
void *data; /**< Transaction Data */
int step; /**< Current step in the sequence.
1 : Initial
2 : Triggered
3 : Triggered-Reply */
struct {
uint8_t type; /**< Message type history */
ogs_pkbuf_t *pkbuf; /**< Packet history */
} seq[3]; /**< history for the each step */
ogs_timer_t *tm_response; /**< Timer waiting for next message */
uint8_t response_rcount;
ogs_timer_t *tm_holding; /**< Timer waiting for holding message */
uint8_t holding_rcount;
ogs_timer_t *tm_peer; /**< Timer waiting for peer message */
void (*peer_cb)(ogs_gtp_xact_t *, void *); /**< timer expiration handler */
void *peer_data; /**< Peer timeout data */
uint32_t local_teid; /**< Local TEID,
expected in reply from peer */
ogs_pool_id_t assoc_xact_id; /**< Associated GTP transaction ID */
void *pfcp_xact; /**< Associated PFCP transaction */
ogs_pool_id_t enb_ue_id;
#define OGS_GTP_MODIFY_TFT_UPDATE ((uint64_t)1<<0)
#define OGS_GTP_MODIFY_QOS_UPDATE ((uint64_t)1<<1)
uint64_t update_flags;
#define OGS_GTP_DELETE_NO_ACTION 1
#define OGS_GTP_DELETE_SEND_AUTHENTICATION_REQUEST 2
#define OGS_GTP_DELETE_SEND_DETACH_ACCEPT 3
#define OGS_GTP_DELETE_SEND_DEACTIVATE_BEARER_CONTEXT_REQUEST 4
#define OGS_GTP_DELETE_SEND_RELEASE_WITH_UE_CONTEXT_REMOVE 5
#define OGS_GTP_DELETE_SEND_RELEASE_WITH_S1_REMOVE_AND_UNLINK 6
#define OGS_GTP_DELETE_HANDLE_PDN_CONNECTIVITY_REQUEST 7
#define OGS_GTP_DELETE_IN_PATH_SWITCH_REQUEST 8
#define OGS_GTP_DELETE_SEND_TAU_ACCEPT 9
int delete_action;
#define OGS_GTP_RELEASE_SEND_UE_CONTEXT_RELEASE_COMMAND 1
#define OGS_GTP_RELEASE_S1_CONTEXT_REMOVE_BY_LO_CONNREFUSED 2
#define OGS_GTP_RELEASE_S1_CONTEXT_REMOVE_BY_RESET_ALL 3
#define OGS_GTP_RELEASE_S1_CONTEXT_REMOVE_BY_RESET_PARTIAL 4
int release_action;
#define OGS_GTP_DELETE_INDIRECT_HANDOVER_COMPLETE 1
#define OGS_GTP_DELETE_INDIRECT_HANDOVER_CANCEL 2
int delete_indirect_action;
#define OGS_GTP_CREATE_IN_ATTACH_REQUEST 1
#define OGS_GTP_CREATE_IN_UPLINK_NAS_TRANSPORT 2
#define OGS_GTP_CREATE_IN_PATH_SWITCH_REQUEST 3
#define OGS_GTP_CREATE_IN_TRACKING_AREA_UPDATE 4 /* 3GPP TS 33.401 9.1.2 */
int create_action;
#define OGS_GTP_MODIFY_IN_PATH_SWITCH_REQUEST 1
#define OGS_GTP_MODIFY_IN_E_RAB_MODIFICATION 2
int modify_action;
} ogs_gtp_xact_t;
int ogs_gtp_xact_init(void);
void ogs_gtp_xact_final(void);
ogs_gtp_xact_t *ogs_gtp1_xact_local_create(ogs_gtp_node_t *gnode,
ogs_gtp1_header_t *hdesc, ogs_pkbuf_t *pkbuf,
void (*cb)(ogs_gtp_xact_t *xact, void *data), void *data);
ogs_gtp_xact_t *ogs_gtp_xact_local_create(ogs_gtp_node_t *gnode,
ogs_gtp2_header_t *hdesc, ogs_pkbuf_t *pkbuf,
void (*cb)(ogs_gtp_xact_t *xact, void *data), void *data);
ogs_gtp_xact_t *ogs_gtp_xact_find_by_id(ogs_pool_id_t id);
void ogs_gtp_xact_delete_all(ogs_gtp_node_t *gnode);
int ogs_gtp1_xact_update_tx(ogs_gtp_xact_t *xact,
ogs_gtp1_header_t *hdesc, ogs_pkbuf_t *pkbuf);
int ogs_gtp_xact_update_tx(ogs_gtp_xact_t *xact,
ogs_gtp2_header_t *hdesc, ogs_pkbuf_t *pkbuf);
int ogs_gtp_xact_commit(ogs_gtp_xact_t *xact);
int ogs_gtp1_xact_receive(ogs_gtp_node_t *gnode,
ogs_gtp1_header_t *h, ogs_gtp_xact_t **xact);
int ogs_gtp_xact_receive(ogs_gtp_node_t *gnode,
ogs_gtp2_header_t *h, ogs_gtp_xact_t **xact);
void ogs_gtp_xact_associate(ogs_gtp_xact_t *xact1, ogs_gtp_xact_t *xact2);
void ogs_gtp_xact_deassociate(ogs_gtp_xact_t *xact1, ogs_gtp_xact_t *xact2);
#ifdef __cplusplus
}
#endif
#endif /* OGS_GTP_XACT_H */
Reference in a new issue View git blame Copy permalink