28 Feb
2022
28 Feb
'22
10:26 a.m.
dexter has submitted this change. ( https://gerrit.osmocom.org/c/osmo-hnbgw/+/27321 )
Change subject: ranap_rab_ass: check for more than one RAB assignment req
......................................................................
ranap_rab_ass: check for more than one RAB assignment req
The spec permits RAB AssignmentRequests with multiple RABs at a time.
Even though one voice call is assigned only one RAB in practice. Since
the current FSM implementation only supports a 1:1 scenario, lets check
if the MSC really assigns only one RAB and block RAB Assignments that do
not fit in this scheme.
Change-Id: I0f1d868fd0b4dc413533d6fcc5482862825181be
Related: OS#5152
---
M include/osmocom/hnbgw/ranap_rab_ass.h
M src/osmo-hnbgw/mgw_fsm.c
M src/osmo-hnbgw/ranap_rab_ass.c
M tests/ranap_rab_ass/ranap_rab_ass_test.c
M tests/ranap_rab_ass/ranap_rab_ass_test.ok
5 files changed, 56 insertions(+), 0 deletions(-)
Approvals:
Jenkins Builder: Verified
dexter: Looks good to me, approved
diff --git a/include/osmocom/hnbgw/ranap_rab_ass.h
b/include/osmocom/hnbgw/ranap_rab_ass.h
index eb18de8..13fd2df 100644
--- a/include/osmocom/hnbgw/ranap_rab_ass.h
+++ b/include/osmocom/hnbgw/ranap_rab_ass.h
@@ -17,3 +17,5 @@
bool ranap_rab_ass_req_ies_check_release(RANAP_RAB_AssignmentRequestIEs_t *ies, uint8_t
rab_id);
bool ranap_rab_ass_resp_ies_check_failure(RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t
rab_id);
+
+int ranap_rab_ass_req_ies_get_count(RANAP_RAB_AssignmentRequestIEs_t *ies);
diff --git a/src/osmo-hnbgw/mgw_fsm.c b/src/osmo-hnbgw/mgw_fsm.c
index 3da2b60..d90571b 100644
--- a/src/osmo-hnbgw/mgw_fsm.c
+++ b/src/osmo-hnbgw/mgw_fsm.c
@@ -689,6 +689,16 @@
mgw_fsm_priv = talloc_zero(map, struct mgw_fsm_priv);
mgw_fsm_priv->ranap_rab_ass_req_message = message;
+ /* This FSM only supports RAB assignments with a single RAB assignment only. This
limitation has been taken
+ * into account under the assumption that voice calls typically require a single RAB
only. Nevertheless, we
+ * will block all incoming RAB assignments that try to assign more (or less) than one
RAB. */
+ if (ranap_rab_ass_req_ies_get_count(&message->msg.raB_AssignmentRequestIEs) != 1)
{
+ LOGP(DMGW, LOGL_ERROR,
+ "mgw_fsm_alloc_and_handle_rab_ass_req() rua_ctx_id=%d, RAB-AssignmentRequest
with more than one RAB assignment -- abort!\n",
+ map->rua_ctx_id);
+ goto error;
+ }
+
/* Parse the RAB Assignment Request now, if it is bad for some reason we will exit early
and not bother with
* creating an FSM etc. */
ies = &mgw_fsm_priv->ranap_rab_ass_req_message->msg.raB_AssignmentRequestIEs;
diff --git a/src/osmo-hnbgw/ranap_rab_ass.c b/src/osmo-hnbgw/ranap_rab_ass.c
index 56886c7..5930451 100644
--- a/src/osmo-hnbgw/ranap_rab_ass.c
+++ b/src/osmo-hnbgw/ranap_rab_ass.c
@@ -620,3 +620,18 @@
return result;
}
+
+/*! Find out how many RAB items are present in a RAB-SetupOrModifyList inside
RANAP_RAB_AssignmentRequestIEs.
+ * \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentRequestIEs.
+ * \returns number of RAB items, -1 on failure. */
+int ranap_rab_ass_req_ies_get_count(RANAP_RAB_AssignmentRequestIEs_t *ies)
+{
+ /* Make sure we indeed deal with a setup-or-modify list */
+ if (!(ies->presenceMask &
RAB_ASSIGNMENTREQUESTIES_RANAP_RAB_SETUPORMODIFYLIST_PRESENT)) {
+ RANAP_DEBUG
+ ("Decoding failed, the RANAP RAB AssignmentRequest did not contain a
setup-or-modify list!\n");
+ return -1;
+ }
+
+ return ies->raB_SetupOrModifyList.list.count;
+}
diff --git a/tests/ranap_rab_ass/ranap_rab_ass_test.c
b/tests/ranap_rab_ass/ranap_rab_ass_test.c
index 052549e..9a98cf8 100644
--- a/tests/ranap_rab_ass/ranap_rab_ass_test.c
+++ b/tests/ranap_rab_ass/ranap_rab_ass_test.c
@@ -320,6 +320,33 @@
ranap_ran_rx_co_free(&message);
}
+void test_ranap_rab_ass_req_ies_get_count(void)
+{
+ int rc;
+ ranap_message message;
+ uint8_t testvec[] = {
+ 0x00, 0x00, 0x00, 0x59, 0x00, 0x00, 0x01, 0x00,
+ 0x36, 0x40, 0x52, 0x00, 0x00, 0x01, 0x00, 0x35,
+ 0x00, 0x48, 0x78, 0x22, 0xcd, 0x80, 0x10, 0x2f,
+ 0xa7, 0x20, 0x1a, 0x2c, 0x00, 0x00, 0xf4, 0x4c,
+ 0x08, 0x0a, 0x02, 0x80, 0x00, 0x51, 0x40, 0x00,
+ 0x27, 0x20, 0x28, 0x14, 0x00, 0x67, 0x40, 0x00,
+ 0x00, 0x22, 0x28, 0x14, 0x00, 0x3c, 0x40, 0x00,
+ 0x00, 0x00, 0x50, 0x3d, 0x02, 0x00, 0x02, 0x27,
+ 0xc0, 0x35, 0x00, 0x01, 0x0a, 0x09, 0x01, 0xa2,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x1f, 0x76,
+ 0x00, 0x00, 0x40, 0x01, 0x00, 0x00
+ };
+
+ rc = ranap_ran_rx_co_decode(talloc_asn1_ctx, &message, testvec, sizeof(testvec));
+ OSMO_ASSERT(rc == 0);
+
+ rc = ranap_rab_ass_req_ies_get_count(&message.msg.raB_AssignmentRequestIEs);
+ printf("ranap_rab_ass_req_ies_get_count rc=%d\n", rc);
+ ranap_ran_rx_co_free(&message);
+}
+
static const struct log_info_cat log_cat[] = {
[DRANAP] = {
.name = "RANAP", .loglevel = LOGL_DEBUG, .enabled = 1,
@@ -382,6 +409,7 @@
test_ranap_rab_ass_resp_ies_replace_inet_addr();
test_ranap_rab_ass_resp_ies_check_failure();
test_ranap_rab_ass_req_ies_check_release();
+ test_ranap_rab_ass_req_ies_get_count();
test_cleanup();
return 0;
diff --git a/tests/ranap_rab_ass/ranap_rab_ass_test.ok
b/tests/ranap_rab_ass/ranap_rab_ass_test.ok
index 688925c..aca4ff3 100644
--- a/tests/ranap_rab_ass/ranap_rab_ass_test.ok
+++ b/tests/ranap_rab_ass/ranap_rab_ass_test.ok
@@ -18,3 +18,4 @@
ranap_rab_ass_resp_ies_check_failure rab_failed_at_hnb=0 (RAB ID 44, which is not in the
message)
ranap_rab_ass_req_ies_check_release rab_release_req=1 (RAB ID 23)
ranap_rab_ass_req_ies_check_release rab_release_req=0 (RAB ID 44, which is not in the
message)
+ranap_rab_ass_req_ies_get_count rc=1
--
To view, visit https://gerrit.osmocom.org/c/osmo-hnbgw/+/27321
To unsubscribe, or for help writing mail filters, visit
https://gerrit.osmocom.org/settings
Gerrit-Project: osmo-hnbgw
Gerrit-Branch: master
Gerrit-Change-Id: I0f1d868fd0b4dc413533d6fcc5482862825181be
Gerrit-Change-Number: 27321
Gerrit-PatchSet: 3
Gerrit-Owner: dexter <pmaier(a)sysmocom.de>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: daniel <dwillmann(a)sysmocom.de>
Gerrit-Reviewer: dexter <pmaier(a)sysmocom.de>
Gerrit-Reviewer: laforge <laforge(a)osmocom.org>
Gerrit-Reviewer: pespin <pespin(a)sysmocom.de>
Gerrit-MessageType: merged