This is merely a historical archive of years 2008-2021, before the migration to mailman3.
A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/gerrit-log@lists.osmocom.org/.
Harald Welte gerrit-no-reply at lists.osmocom.orgHarald Welte has submitted this change and it was merged. ( https://gerrit.osmocom.org/13291 )
Change subject: gprs_ns: Don't use initial IP/port for anything but SNS
......................................................................
gprs_ns: Don't use initial IP/port for anything but SNS
Section 6.2.1 of 3GPP TS 48.016 states:
> A pre-configured endpoint shall not be used for NSE data or signalling
> traffic (with the exception of Size and Configuration procedures) unless
> it is configured by the SGSN using the auto-configuration procedures.
However, in the current SNS implementation, the initial IP/Port over
which we perform the SNS-SIZE + SNS-CONFIG are treated as one of the
normal NS-VCs. Specifically, we also perform the NS-ALIVE procedure on
it, which is clearly wrong.
Let's explicitly create the "initial" NS-VC with data and signalling
weight of 0, and ensure we never start the alive timer or send any
non-SNS PDUs on this connection as long as SNS was not used to change
either of the two weights to non-zero.
While at it, also safeguard against processing any incoming non-SNS
messages on such a all-zero-weight connection.
Change-Id: I16a91a07e5914d123b2ea2f8413b94e7cd518628
Closes: OS#3844
---
M src/gb/gprs_ns.c
1 file changed, 55 insertions(+), 2 deletions(-)
Approvals:
Jenkins Builder: Verified
Harald Welte: Looks good to me, approved
diff --git a/src/gb/gprs_ns.c b/src/gb/gprs_ns.c
index 93c219c..8c3b0fa 100644
--- a/src/gb/gprs_ns.c
+++ b/src/gb/gprs_ns.c
@@ -195,6 +195,14 @@
LOGP(DNS, LOGL_ERROR, "TX failed (%d) to peer %s\n", \
rc, gprs_ns_ll_str(nsvc));
+static bool nsvc_is_not_used(const struct gprs_nsvc *nsvc)
+{
+ if (nsvc->data_weight == 0 && nsvc->sig_weight == 0)
+ return true;
+ else
+ return false;
+}
+
struct msgb *gprs_ns_msgb_alloc(void)
{
struct msgb *msg = msgb_alloc_headroom(NS_ALLOC_SIZE, NS_ALLOC_HEADROOM,
@@ -444,12 +452,40 @@
static int nsip_sendmsg(struct gprs_nsvc *nsvc, struct msgb *msg);
extern int grps_ns_frgre_sendmsg(struct gprs_nsvc *nsvc, struct msgb *msg);
+static bool ns_is_sns(uint8_t pdu_type)
+{
+ switch (pdu_type) {
+ case SNS_PDUT_CONFIG:
+ case SNS_PDUT_ACK:
+ case SNS_PDUT_ADD:
+ case SNS_PDUT_CHANGE_WEIGHT:
+ case SNS_PDUT_DELETE:
+ case SNS_PDUT_CONFIG_ACK:
+ case SNS_PDUT_SIZE:
+ case SNS_PDUT_SIZE_ACK:
+ return true;
+ default:
+ return false;
+ }
+}
+
static int gprs_ns_tx(struct gprs_nsvc *nsvc, struct msgb *msg)
{
+ struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h;
int ret;
log_set_context(LOG_CTX_GB_NSVC, nsvc);
+ /* A pre-configured endpoint shall not be used for NSE data or signalling
+ * traffic (with the exception of Size and Configuration procedures) unless it
+ * is configured by the SGSN using the auto-configuration procedures. */
+ if (nsvc_is_not_used(nsvc) && !ns_is_sns(nsh->pdu_type) && nsh->pdu_type != NS_PDUT_STATUS) {
+ LOGP(DNS, LOGL_NOTICE, "Not transmitting %s on unused/pre-configured endpoint\n",
+ get_value_string(gprs_ns_pdu_strings, nsh->pdu_type));
+ msgb_free(msg);
+ return -EINVAL;
+ }
+
/* Increment number of Uplink bytes */
rate_ctr_inc(&nsvc->ctrg->ctr[NS_CTR_PKTS_OUT]);
rate_ctr_add(&nsvc->ctrg->ctr[NS_CTR_BYTES_OUT], msgb_l2len(msg));
@@ -1690,6 +1726,13 @@
rate_ctr_inc(&(*nsvc)->ctrg->ctr[NS_CTR_PKTS_IN]);
rate_ctr_add(&(*nsvc)->ctrg->ctr[NS_CTR_BYTES_IN], msgb_l2len(msg));
+ if (nsvc_is_not_used(*nsvc) && !ns_is_sns(nsh->pdu_type) && nsh->pdu_type != NS_PDUT_STATUS) {
+ LOGP(DNS, LOGL_NOTICE, "NSEI=%u Rx %s on unused/pre-configured endpoint, discarding\n",
+ (*nsvc)->nsei, get_value_string(gprs_ns_pdu_strings, nsh->pdu_type));
+ gprs_ns_tx_status(*nsvc, NS_CAUSE_PROTO_ERR_UNSPEC, 0, msg);
+ return 0;
+ }
+
switch (nsh->pdu_type) {
case NS_PDUT_ALIVE:
/* If we're dead and blocked and suddenly receive a
@@ -2116,8 +2159,14 @@
* require some massive code and API changes compared to existing libosmogb,
* so let's keep the old logic. */
nsvc = gprs_nsvc_by_rem_addr(nsi, dest);
- if (!nsvc)
- nsvc = gprs_nsvc_create(nsi, nsvci);
+ if (!nsvc) {
+ /* create NSVC with 0 data + signalling weight. This is illegal in SNS
+ * and can hence only be created locally and serves as indication that
+ * this NS-VC shall not be used for anything except SNS _unless_ it is
+ * modified via SNS-{CONFIG,CHANGEWEIGHT,ADD} to become part of the
+ * active NS-VCs */
+ nsvc = gprs_nsvc_create2(nsi, nsvci, 0, 0);
+ }
nsvc->ip.bts_addr = *dest;
nsvc->nsei = nsei;
nsvc->remote_end_is_sgsn = 1;
@@ -2161,6 +2210,10 @@
/*! Start the ALIVE timer procedure in all NS-VCs part of this NS Instance */
void gprs_nsvc_start_test(struct gprs_nsvc *nsvc)
{
+ /* skip the initial NS-VC unless it has explicitly been configured
+ * via SNS-CONFIG from the SGSN */
+ if (nsvc_is_not_used(nsvc))
+ return;
gprs_ns_tx_alive(nsvc);
nsvc_start_timer(nsvc, NSVC_TIMER_TNS_TEST);
}
--
To view, visit https://gerrit.osmocom.org/13291
To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings
Gerrit-Project: libosmocore
Gerrit-Branch: master
Gerrit-MessageType: merged
Gerrit-Change-Id: I16a91a07e5914d123b2ea2f8413b94e7cd518628
Gerrit-Change-Number: 13291
Gerrit-PatchSet: 2
Gerrit-Owner: Harald Welte <laforge at gnumonks.org>
Gerrit-Reviewer: Harald Welte <laforge at gnumonks.org>
Gerrit-Reviewer: Jenkins Builder (1000002)
Gerrit-CC: Alexander Chemeris <Alexander.Chemeris at gmail.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/gerrit-log/attachments/20190317/7f1b6a8f/attachment.htm>