summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorNeels Hofmeyr <nhofmeyr@sysmocom.de>2016-06-13 12:28:21 +0200
committerNeels Hofmeyr <nhofmeyr@sysmocom.de>2016-06-16 04:29:40 +0200
commit285df2ec624f5c51ca5621de0524fba64226d4ed (patch)
tree7ec59aa3c9a40e44f25fa2473c0c98d73f9f23f8
parent3201988f7bcfeef4c3acbcadfbda0174e4635b98 (diff)
dyn PDCH: add lchan sanity checks in PDCH DE/ACT ACK
-rw-r--r--openbsc/src/libbsc/abis_rsl.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/openbsc/src/libbsc/abis_rsl.c b/openbsc/src/libbsc/abis_rsl.c
index 349b3de39..3aefd9c13 100644
--- a/openbsc/src/libbsc/abis_rsl.c
+++ b/openbsc/src/libbsc/abis_rsl.c
@@ -1201,8 +1201,59 @@ static int rsl_rx_hando_det(struct msgb *msg)
return 0;
}
+static bool lchan_may_change_pdch(struct gsm_lchan *lchan, bool pdch_act)
+{
+ struct gsm_bts_trx_ts *ts;
+ bool ok;
+
+ OSMO_ASSERT(lchan);
+
+ ts = lchan->ts;
+ OSMO_ASSERT(ts);
+ OSMO_ASSERT(ts->trx);
+ OSMO_ASSERT(ts->trx->bts);
+
+ if (lchan->ts->pchan != GSM_PCHAN_TCH_F_PDCH) {
+ LOGP(DRSL, LOGL_ERROR, "(bts %u, trx %u, ts %u, pchan %s)"
+ " Rx PDCH %s ACK for channel that is no TCH/F_PDCH\n",
+ ts->trx->bts->nr, ts->trx->nr, ts->nr,
+ gsm_pchan_name(ts->pchan),
+ pdch_act? "ACT" : "DEACT");
+ return false;
+ }
+
+ /* During BTS initialization, we expect to PDCH ACT in channel state ==
+ * NONE. However, during dynamic channel switching, we will PDCH ACT
+ * while in state DEACTIVATION REQUESTED (we're deactivating TCH/F
+ * while activating PDCH); and we will PDCH DEACT while in state
+ * ACTIVATION REQUESTED (we're activating TCH/F while deactivating
+ * PDCH). */
+ /* FIXME: rather switch PDCH while in state NONE, i.e. after
+ * deactivation of TCH/F and before activation of TCH/F? */
+ if (pdch_act)
+ ok = (lchan->state == LCHAN_S_NONE
+ || lchan->state == LCHAN_S_REL_REQ);
+ else
+ ok = (lchan->state == LCHAN_S_NONE
+ || lchan->state == LCHAN_S_ACT_REQ);
+
+ if (!ok) {
+ LOGP(DRSL, LOGL_ERROR, "(bts %u, trx %u, ts %u, pchan %s)"
+ " Rx PDCH %s ACK in unexpected state: %s\n",
+ ts->trx->bts->nr, ts->trx->nr, ts->nr,
+ gsm_pchan_name(ts->pchan),
+ pdch_act? "ACT" : "DEACT",
+ gsm_lchans_name(lchan->state));
+ return false;
+ }
+ return true;
+}
+
static int rsl_rx_pdch_act_ack(struct msgb *msg)
{
+ if (!lchan_may_change_pdch(msg->lchan, true))
+ return -EINVAL;
+
msg->lchan->ts->flags |= TS_F_PDCH_ACTIVE;
msg->lchan->ts->flags &= ~TS_F_PDCH_ACT_PENDING;
@@ -1214,6 +1265,9 @@ static int rsl_rx_pdch_act_ack(struct msgb *msg)
static int rsl_rx_pdch_deact_ack(struct msgb *msg)
{
+ if (!lchan_may_change_pdch(msg->lchan, false))
+ return -EINVAL;
+
msg->lchan->ts->flags &= ~TS_F_PDCH_ACTIVE;
msg->lchan->ts->flags &= ~TS_F_PDCH_DEACT_PENDING;