properly receive BSSMAP Clear Complete and Iu Release Complete
When sending a BSSMAP Clear or Iu Release, do not immediately discard the conn,
but wait until a BSSMAP Clear Complete / Iu Release Complete has been received.
Hence we will no longer show in the log that an incoming Release/Clear Complete
belongs to an unknown subscriber, but will still be around to properly log the
release.
Related: OS#3122
Change-Id: Ie4c6aaba3866d6e5b98004e8870a215e8cf8ffc1
diff --git a/src/libmsc/a_iface_bssap.c b/src/libmsc/a_iface_bssap.c
index d0d6bc0..87ccf05 100644
--- a/src/libmsc/a_iface_bssap.c
+++ b/src/libmsc/a_iface_bssap.c
@@ -239,11 +239,16 @@
/* Endpoint to handle BSSMAP clear complete */
static int bssmap_rx_clear_complete(struct osmo_sccp_user *scu,
- const struct a_conn_info *a_conn_info, struct msgb *msg)
+ const struct a_conn_info *a_conn_info,
+ struct gsm_subscriber_connection *conn)
{
int rc;
- LOGP(DMSC, LOGL_INFO, "Rx BSSMAP CLEAR COMPLETE, releasing SCCP connection\n");
+ LOGPCONN(conn, LOGL_INFO, "Rx BSSMAP CLEAR COMPLETE, releasing SCCP connection\n");
+
+ if (conn)
+ msc_subscr_conn_rx_bssmap_clear_complete(conn);
+
rc = osmo_sccp_tx_disconn(scu, a_conn_info->conn_id,
NULL, SCCP_RELEASE_CAUSE_END_USER_ORIGINATED);
@@ -568,8 +573,6 @@
switch (msg_type) {
case BSS_MAP_MSG_COMPLETE_LAYER_3:
return bssmap_rx_l3_compl(scu, a_conn_info, msg, &tp);
- case BSS_MAP_MSG_CLEAR_COMPLETE:
- return bssmap_rx_clear_complete(scu, a_conn_info, msg);
default:
break;
}
@@ -577,6 +580,13 @@
conn = subscr_conn_lookup_a(a_conn_info->network, a_conn_info->conn_id);
if (!conn) {
LOGP(DBSSAP, LOGL_ERROR, "Couldn't find subscr_conn for conn_id=%d\n", a_conn_info->conn_id);
+ /* We expect a Clear Complete to come in on a valid conn. But if for some reason we still
+ * have the SCCP connection while the subscriber connection data is already gone, at
+ * least close the SCCP conn. */
+
+ if (msg_type == BSS_MAP_MSG_CLEAR_COMPLETE)
+ return bssmap_rx_clear_complete(scu, a_conn_info, NULL);
+
return -EINVAL;
}
@@ -585,6 +595,8 @@
switch (msg_type) {
case BSS_MAP_MSG_CLEAR_RQST:
return bssmap_rx_clear_rqst(conn, msg, &tp);
+ case BSS_MAP_MSG_CLEAR_COMPLETE:
+ return bssmap_rx_clear_complete(scu, a_conn_info, conn);
case BSS_MAP_MSG_CLASSMARK_UPDATE:
return bssmap_rx_classmark_upd(conn, msg, &tp);
case BSS_MAP_MSG_CIPHER_MODE_COMPLETE:
diff --git a/src/libmsc/iucs_ranap.c b/src/libmsc/iucs_ranap.c
index 57cd50e..ec0b569 100644
--- a/src/libmsc/iucs_ranap.c
+++ b/src/libmsc/iucs_ranap.c
@@ -117,7 +117,7 @@
case RANAP_IU_EVENT_LINK_INVALIDATED:
LOGP(DIUCS, LOGL_INFO, "IuCS release for %s\n",
vlr_subscr_name(conn->vsub));
- msc_subscr_conn_close(conn, 0);
+ msc_subscr_conn_rx_iu_release_complete(conn);
return 0;
case RANAP_IU_EVENT_SECURITY_MODE_COMPLETE:
diff --git a/src/libmsc/osmo_msc.c b/src/libmsc/osmo_msc.c
index a5184b2..cc67a5a 100644
--- a/src/libmsc/osmo_msc.c
+++ b/src/libmsc/osmo_msc.c
@@ -283,6 +283,11 @@
osmo_fsm_inst_dispatch(conn->fi, SUBSCR_CONN_E_UNUSED, NULL);
}
+bool msc_subscr_conn_used_by(struct gsm_subscriber_connection *conn, enum msc_subscr_conn_use token)
+{
+ return conn && (conn->use_tokens & (1 << token));
+}
+
const struct value_string msc_subscr_conn_use_names[] = {
{MSC_CONN_USE_UNTRACKED, "UNTRACKED"},
{MSC_CONN_USE_COMPL_L3, "compl_l3"},
diff --git a/src/libmsc/subscr_conn.c b/src/libmsc/subscr_conn.c
index e3a6b24..1ca6b2d 100644
--- a/src/libmsc/subscr_conn.c
+++ b/src/libmsc/subscr_conn.c
@@ -260,8 +260,11 @@
{
struct gsm_subscriber_connection *conn = fi->priv;
- /* While we're still checking on release, prevent a last use count decrement from deallocating */
- msc_subscr_conn_get(conn, MSC_CONN_USE_RELEASE);
+ /* Use count for either conn->a.waiting_for_clear_complete or
+ * conn->iu.waiting_for_release_complete. 'get' it early, so we don't deallocate after tearing
+ * down active transactions. Safeguard against double-get (though it shouldn't happen). */
+ if (!msc_subscr_conn_used_by(conn, MSC_CONN_USE_RELEASE))
+ msc_subscr_conn_get(conn, MSC_CONN_USE_RELEASE);
/* Cancel pending CM Service Requests */
if (conn->received_cm_service_request) {
@@ -278,20 +281,27 @@
switch (conn->via_ran) {
case RAN_GERAN_A:
a_iface_tx_clear_cmd(conn);
+ if (conn->a.waiting_for_clear_complete) {
+ LOGPFSML(fi, LOGL_ERROR,
+ "Unexpected: conn is already waiting for BSSMAP Clear Complete\n");
+ break;
+ }
+ conn->a.waiting_for_clear_complete = true;
break;
case RAN_UTRAN_IU:
ranap_iu_tx_release(conn->iu.ue_ctx, NULL);
+ if (conn->iu.waiting_for_release_complete) {
+ LOGPFSML(fi, LOGL_ERROR,
+ "Unexpected: conn is already waiting for Iu Release Complete\n");
+ break;
+ }
+ conn->iu.waiting_for_release_complete = true;
break;
default:
LOGP(DMM, LOGL_ERROR, "%s: Unknown RAN type, cannot tx release/clear\n",
vlr_subscr_name(conn->vsub));
break;
}
-
- /* FIXME: keep the conn until the Iu Release Outcome is
- * received from the UE, or a timeout expires. For now, the log
- * says "unknown UE" for each release outcome. */
- msc_subscr_conn_put(conn, MSC_CONN_USE_RELEASE);
}
static void subscr_conn_fsm_releasing(struct osmo_fsm_inst *fi, uint32_t event, void *data)
@@ -456,7 +466,7 @@
osmo_fsm_inst_dispatch(conn->fi, SUBSCR_CONN_E_RELEASE_WHEN_UNUSED, NULL);
}
-void msc_subscr_conn_close(struct gsm_subscriber_connection *conn, uint32_t cause)
+static void conn_close(struct gsm_subscriber_connection *conn, uint32_t cause, uint32_t event)
{
if (!conn) {
LOGP(DMM, LOGL_ERROR, "Cannot release NULL connection\n");
@@ -467,11 +477,23 @@
__func__, vlr_subscr_name(conn->vsub), cause);
return;
}
- osmo_fsm_inst_dispatch(conn->fi, SUBSCR_CONN_E_CN_CLOSE, &cause);
+ osmo_fsm_inst_dispatch(conn->fi, event, &cause);
+}
+
+void msc_subscr_conn_close(struct gsm_subscriber_connection *conn, uint32_t cause)
+{
+ return conn_close(conn, cause, SUBSCR_CONN_E_CN_CLOSE);
+}
+
+void msc_subscr_conn_mo_close(struct gsm_subscriber_connection *conn, uint32_t cause)
+{
+ return conn_close(conn, cause, SUBSCR_CONN_E_MO_CLOSE);
}
bool msc_subscr_conn_in_release(struct gsm_subscriber_connection *conn)
{
+ if (!conn || !conn->fi)
+ return true;
if (conn->fi->state == SUBSCR_CONN_S_RELEASING)
return true;
if (conn->fi->state == SUBSCR_CONN_S_RELEASED)
@@ -491,7 +513,8 @@
return true;
}
-/* Indicate that *some* communication is happening with the phone. */
+/* Indicate that *some* communication is happening with the phone, so that the conn FSM no longer times
+ * out to release within a few seconds. */
void msc_subscr_conn_communicating(struct gsm_subscriber_connection *conn)
{
osmo_fsm_inst_dispatch(conn->fi, SUBSCR_CONN_E_COMMUNICATING, NULL);
@@ -544,6 +567,7 @@
return conn->fi->state == SUBSCR_CONN_S_AUTH_CIPH;
}
+
const struct value_string complete_layer3_type_names[] = {
{ COMPLETE_LAYER3_NONE, "NONE" },
{ COMPLETE_LAYER3_LU, "LU" },
@@ -559,3 +583,30 @@
osmo_fsm_inst_update_id(conn->fi, id);
LOGPFSML(conn->fi, LOGL_DEBUG, "Updated ID from %s\n", complete_layer3_type_name(from));
}
+
+static void rx_close_complete(struct gsm_subscriber_connection *conn, const char *label, bool *flag)
+{
+ if (!conn)
+ return;
+ if (!msc_subscr_conn_in_release(conn)) {
+ LOGPFSML(conn->fi, LOGL_ERROR, "Received unexpected %s, discarding right now\n",
+ label);
+ trans_conn_closed(conn);
+ osmo_fsm_inst_term(conn->fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+ if (*flag) {
+ *flag = false;
+ msc_subscr_conn_put(conn, MSC_CONN_USE_RELEASE);
+ }
+}
+
+void msc_subscr_conn_rx_bssmap_clear_complete(struct gsm_subscriber_connection *conn)
+{
+ rx_close_complete(conn, "BSSMAP Clear Complete", &conn->a.waiting_for_clear_complete);
+}
+
+void msc_subscr_conn_rx_iu_release_complete(struct gsm_subscriber_connection *conn)
+{
+ rx_close_complete(conn, "Iu Release Complete", &conn->iu.waiting_for_release_complete);
+}