diff options
| -rw-r--r-- | src/libbsc/abis_rsl.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/src/libbsc/abis_rsl.c b/src/libbsc/abis_rsl.c index 3f8bbc904..189316631 100644 --- a/src/libbsc/abis_rsl.c +++ b/src/libbsc/abis_rsl.c @@ -2180,6 +2180,20 @@ static int abis_rsl_rx_rll(struct msgb *msg) case RSL_MT_EST_IND: DEBUGPC(DRLL, "ESTABLISH INDICATION\n"); /* lchan is established, stop T3101 */ + + /* Note: By definition the first Establish Indication must + * happen first on SAPI 0, once the connection on SAPI 0 is + * made, parallel connections on other SAPIs are permitted */ + if (sapi != 0 && msg->lchan->sapis[0] != LCHAN_SAPI_MS) { + LOGP(DRLL, LOGL_NOTICE, "MS attempted to establish DCCH on SAPI=%d (expected SAPI=0)\n", + rllh->link_id & 0x7); + + /* Note: We do not need to close the channel, + * since we might still get a proper Establish Ind. + * If not, T3101 will close the channel on timeout. */ + break; + } + msg->lchan->sapis[rllh->link_id & 0x7] = LCHAN_SAPI_MS; osmo_timer_del(&msg->lchan->T3101); if (msgb_l2len(msg) > |