NS: Optionally disable NS-{RESET,BLOCK,UNBLOCK} when using UDP/IP
3GPP TS 48.016 is quite clear in that no NS-{RESET,BLOCK,UNBLOCK}
procedures shall be used over an IP based transport. They are only
for use in Frame Relay based transport.
However, as libosmogb was first developed against ip.access nanoBTS,
and their Gb implementation mandates those procedures, we
unconditionally implemented those procedures back then. Let's
give the user the option of disabling this behavior to become
more spec compliant (and interoperate with more other vendors out
there).
Change-Id: Ic4eba1b4dcbeac00f5879db295e0a9f1a50f71d8
diff --git a/src/gb/gprs_ns.c b/src/gb/gprs_ns.c
index 4e584ad..f1b36f4 100644
--- a/src/gb/gprs_ns.c
+++ b/src/gb/gprs_ns.c
@@ -327,7 +327,7 @@
nsvc->nsvci = nsvci;
nsvc->nsvci_is_valid = 1;
/* before RESET procedure: BLOCKED and DEAD */
- if (nsi->bss_sns_fi)
+ if (nsi->bss_sns_fi || !nsi->nsip.use_reset_block_unblock)
ns_set_state(nsvc, 0);
else
ns_set_state(nsvc, NSE_S_BLOCKED);
@@ -793,7 +793,7 @@
nsvc->nsi->timeout[NS_TOUT_TNS_ALIVE_RETRIES]) {
/* mark as dead (and blocked unless IP-SNS) */
rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_DEAD]);
- if (!nsvc->nsi->bss_sns_fi) {
+ if (!nsvc->nsi->bss_sns_fi && nsvc->nsi->nsip.use_reset_block_unblock) {
ns_set_state(nsvc, NSE_S_BLOCKED);
rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_BLOCKED]);
} else
@@ -804,7 +804,7 @@
nsvc->nsi->timeout[NS_TOUT_TNS_ALIVE_RETRIES]);
ns_osmo_signal_dispatch(nsvc, S_NS_ALIVE_EXP, 0);
/* FIXME: should we send this signal in case of SNS? */
- if (!nsvc->nsi->bss_sns_fi)
+ if (!nsvc->nsi->bss_sns_fi && nsvc->nsi->nsip.use_reset_block_unblock)
ns_osmo_signal_dispatch(nsvc, S_NS_BLOCK, NS_CAUSE_NSVC_BLOCKED);
return;
}
@@ -1758,8 +1758,12 @@
* fine. */
if ((*nsvc)->state == NSE_S_BLOCKED)
rc = gprs_nsvc_reset((*nsvc), NS_CAUSE_PDU_INCOMP_PSTATE);
- else if (!((*nsvc)->state & NSE_S_RESET))
+ else if (!((*nsvc)->state & NSE_S_RESET)) {
+ /* if we're not alive, we cannot transmit the ACK; set ALIVE */
+ if (!((*nsvc)->state & NSE_S_ALIVE))
+ ns_mark_alive(*nsvc);
rc = gprs_ns_tx_alive_ack(*nsvc);
+ }
break;
case NS_PDUT_ALIVE_ACK:
ns_mark_alive(*nsvc);
@@ -1915,6 +1919,11 @@
llist_del(&nsi->unknown_nsvc->list);
INIT_LLIST_HEAD(&nsi->unknown_nsvc->list);
+ /* By default we are in IPA compatible mode, that is we use NS-RESET, NS-BLOCK
+ * and NS-UNBLOCK procedures even for an IP/UDP based Gb interface, in violation
+ * of 3GPP TS 48.016. */
+ nsi->nsip.use_reset_block_unblock = true;
+
return nsi;
}