RSL: keep track if a channel is active or not
This allows us to block packets that we have received after the channel
is no longer being used. This is visible during handover, where we still
receive a measurement report after the MS has switched to the new channel.
This leftover measurement report then attempts to trigger another handover,
which si bogus and will fail - and thus only consumes resources.
With the new LCHAN_S_ACTIVE state, we can check for this when processing
the measurement report.
diff --git a/openbsc/src/abis_rsl.c b/openbsc/src/abis_rsl.c
index a50d7aa..72ae9db 100644
--- a/openbsc/src/abis_rsl.c
+++ b/openbsc/src/abis_rsl.c
@@ -918,6 +918,8 @@
if (rslh->ie_chan != RSL_IE_CHAN_NR)
return -EINVAL;
+ msg->lchan->state = LCHAN_S_ACTIVE;
+
dispatch_signal(SS_LCHAN, S_LCHAN_ACTIVATE_ACK, msg->lchan);
return 0;
@@ -938,6 +940,8 @@
print_rsl_cause(TLVP_VAL(&tp, RSL_IE_CAUSE),
TLVP_LEN(&tp, RSL_IE_CAUSE));
+ msg->lchan->state = LCHAN_S_NONE;
+
dispatch_signal(SS_LCHAN, S_LCHAN_ACTIVATE_NACK, msg->lchan);
lchan_free(msg->lchan);
@@ -1022,6 +1026,11 @@
const u_int8_t *val;
int rc;
+ /* check if this channel is actually active */
+ /* FIXME: maybe this check should be way more generic/centralized */
+ if (msg->lchan->state != LCHAN_S_ACTIVE)
+ return 0;
+
memset(mr, 0, sizeof(*mr));
mr->lchan = msg->lchan;
@@ -1128,6 +1137,7 @@
break;
case RSL_MT_RF_CHAN_REL_ACK:
DEBUGPC(DRSL, "RF CHANNEL RELEASE ACK\n");
+ msg->lchan->state = LCHAN_S_NONE;
lchan_free(msg->lchan);
break;
case RSL_MT_MODE_MODIFY_ACK: