cellular-infrastructure
/
osmo-msc
mirror of https://gerrit.osmocom.org/osmo-msc
9
0
Fork 0
Code Issues Releases Wiki Activity

libmsc/gsm_09_11.c: do not abuse LOG_TRANS() and early trans allocation 

In case of network-originated SS/USSD session establishment, we
need to verify the received GSUP PROC_SS_REQ message and make
sure that all mandatory IEs are present.

There is no sensible need to allocate a new transaction before
doing all the checks, other than the ability to use LOG_TRANS().
This complicates the code, so let's avoid the early allocation.

Change-Id: I4e027b19e8065a39324a1647957cef4066b82ce7
This commit is contained in:
Vadim Yanitskiy 2019-06-15 15:52:23 +07:00
parent 58abc67caa
commit 10c3ce563b
2 changed files with 21 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
src/libmsc/gsm_09_11.c
View File

@ -317,53 +317,43 @@ static struct gsm_trans *establish_nc_ss_trans(struct gsm_network *net,
struct gsm_trans *trans, *transt;
int tid;
/* Allocate transaction first, for log context */
trans = trans_alloc(net, vsub, TRANS_USSD,
TRANS_ID_UNASSIGNED, gsup_msg->session_id);
if (!trans) {
LOG_TRANS(trans, LOGL_ERROR, " -> No memory for trans\n");
return NULL;
}
if (gsup_msg->session_state != OSMO_GSUP_SESSION_STATE_BEGIN) {
LOG_TRANS(trans, LOGL_ERROR, "Received non-BEGIN message "
"for non-existing transaction\n");
trans_free(trans);
LOGP(DSS, LOGL_ERROR, "Received non-BEGIN message for non-existing transaction\n");
return NULL;
}
LOGP(DSS, LOGL_DEBUG, "(%s) Establishing a network-originated session (id=0x%x)\n",
vlr_subscr_name(vsub), gsup_msg->session_id);
if (!gsup_msg->ss_info || gsup_msg->ss_info_len < 2) {
LOG_TRANS(trans, LOGL_ERROR, "Missing mandatory Facility IE\n");
trans_free(trans);
LOGP(DSS, LOGL_ERROR, "Missing mandatory Facility IE\n");
return NULL;
}
/* If subscriber is not "attached" */
if (!vsub->cgi.lai.lac) {
LOG_TRANS(trans, LOGL_ERROR, "Network-originated session "
LOGP(DSS, LOGL_ERROR, "Network-originated session "
"rejected - subscriber is not attached\n");
trans_free(trans);
return NULL;
}
LOG_TRANS(trans, LOGL_DEBUG, "Establishing network-originated session\n");
/* Obtain an unused transaction ID */
tid = trans_assign_trans_id(net, vsub, TRANS_USSD);
if (tid < 0) {
LOGP(DSS, LOGL_ERROR, "No free transaction ID\n");
return NULL;
}
/* Allocate a new NCSS transaction */
trans = trans_alloc(net, vsub, TRANS_USSD, tid, gsup_msg->session_id);
if (!trans) {
LOGP(DSS, LOGL_ERROR, " -> No memory for trans\n");
return NULL;
}
/* Count active NC SS/USSD sessions */
osmo_counter_inc(net->active_nc_ss);
/* Assign transaction ID */
tid = trans_assign_trans_id(trans->net, trans->vsub, TRANS_USSD);
if (tid < 0) {
LOG_TRANS(trans, LOGL_ERROR, "No free transaction ID\n");
/* TODO: inform HLR about this */
/* TODO: release connection with subscriber */
trans->callref = 0;
trans_free(trans);
return NULL;
}
trans->transaction_id = tid;
/* Init inactivity timer */
osmo_timer_setup(&trans->ss.timer_guard,
ncss_session_timeout_handler, trans);

4
tests/msc_vlr/msc_vlr_test_ss.err
View File

@ -367,9 +367,9 @@ DREF VLR subscr IMSI-901700000004620:MSISDN-46071 + _test_ss_ussd_no: now used b
llist_count(&vsub->cs.requests) == 0
<-- GSUP rx OSMO_GSUP_MSGT_PROC_SS_REQUEST: 20010809710000004026f03004200001013101013515a11302010102013b300b04010f0406aa510c061b010a0103
DREF VLR subscr IMSI-901700000004620:MSISDN-46071 + gsm0911_gsup_rx: now used by 3 (attached,_test_ss_ussd_no,gsm0911_gsup_rx)
DSS (IMSI-901700000004620:MSISDN-46071) Establishing a network-originated session (id=0x20000101)
DREF VLR subscr IMSI-901700000004620:MSISDN-46071 + NCSS: now used by 4 (attached,_test_ss_ussd_no,gsm0911_gsup_rx,NCSS)
DSS trans(NCSS IMSI-901700000004620:MSISDN-46071 callref-0x20000101 tid-255) New transaction
DSS trans(NCSS IMSI-901700000004620:MSISDN-46071 callref-0x20000101 tid-255) Establishing network-originated session
DSS trans(NCSS IMSI-901700000004620:MSISDN-46071 callref-0x20000101 tid-0) New transaction
DSS trans(NCSS IMSI-901700000004620:MSISDN-46071 callref-0x20000101 tid-0) Triggering Paging Request
DPAG Paging: IMSI-901700000004620:MSISDN-46071 for GSM 09.11 SS/USSD: Starting paging
paging request (SIGNALLING_HIGH_PRIO) to IMSI-901700000004620:MSISDN-46071 on GERAN-A