ensure unique CellIDs in HNB-GW
If we receive a HNB-REGISTER-REQ with a cell ID which is already used
by another registered NNB, log an error and send HNB-REGISTER-REJECT.
Tested manually by running two 'hnb-test' programs concurrently (they
need to listen on different telnet ports; this port is hard-coded so
I compiled two different hnb-test binaries).
Then I issued the 'hnbap hnb register' command on the telnet interface
of each, and verified that the correct action is logged by osmo-hnbgw.
Both hnb-test programs can connect, but only one of them can register
at a time. Killing a registered 'hnb-test' program terminates its
connection and allows the previously rejected one to register.
The new rejection log message looks like this:
hnbgw_hnbap.c:429 rejecting HNB-REGISTER-REQ with duplicate cell
identity MCC=901,MNC=99,LAC=49406,RAC=66,SAC=43947,CID=182250155
from (r=127.0.0.1:42828<->l=127.0.0.1:29169)
This change depends on a new API in libosmo-netif, which is added in
https://gerrit.osmocom.org/#/c/6844/
Change-Id: Iffd441eb2b6b75dfbe001b49b01bea015ca6e11c
Depends: I8ed78fe39c463e9018756700d13ee5ebe003b57f
Related: OS#2789
diff --git a/src/hnbgw_hnbap.c b/src/hnbgw_hnbap.c
index 8fba13c..acc5aff 100644
--- a/src/hnbgw_hnbap.c
+++ b/src/hnbgw_hnbap.c
@@ -20,6 +20,7 @@
#include <osmocom/core/msgb.h>
#include <osmocom/core/utils.h>
+#include <osmocom/core/socket.h>
#include <osmocom/gsm/gsm48.h>
#include <osmocom/netif/stream.h>
@@ -48,6 +49,45 @@
return 0;
}
+static int hnbgw_tx_hnb_register_rej(struct hnb_context *ctx)
+{
+ HNBRegisterReject_t reject_out;
+ HNBRegisterRejectIEs_t reject;
+ struct msgb *msg;
+ int rc;
+
+ reject.presenceMask = 0,
+ reject.cause.present = Cause_PR_radioNetwork;
+ reject.cause.choice.radioNetwork = CauseRadioNetwork_unspecified;
+
+ /* encode the Information Elements */
+ memset(&reject_out, 0, sizeof(reject_out));
+ rc = hnbap_encode_hnbregisterrejecties(&reject_out, &reject);
+ if (rc < 0) {
+ LOGP(DHNBAP, LOGL_ERROR, "Failure to encode HNB-REGISTER-REJECT to %s: rc=%d\n",
+ ctx->identity_info, rc);
+ return rc;
+ }
+
+ /* generate a successfull outcome PDU */
+ msg = hnbap_generate_unsuccessful_outcome(ProcedureCode_id_HNBRegister,
+ Criticality_reject,
+ &asn_DEF_HNBRegisterReject,
+ &reject_out);
+
+ ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_HNBRegisterReject, &reject_out);
+
+ rc = hnbgw_hnbap_tx(ctx, msg);
+ if (rc == 0) {
+ /* Tell libosmo-netif to destroy this connection when it is done
+ * sending our HNB-REGISTER-REJECT response. */
+ osmo_stream_srv_set_flush_and_destroy(ctx->conn);
+ } else {
+ /* The message was not queued. Destroy the connection right away. */
+ hnb_context_release(ctx, true);
+ }
+}
+
static int hnbgw_tx_hnb_register_acc(struct hnb_context *ctx)
{
HNBRegisterAccept_t accept_out;
@@ -361,13 +401,14 @@
hnbap_cause_str(&ies.cause));
hnbap_free_hnbde_registeries(&ies);
- hnb_context_release(ctx);
+ hnb_context_release(ctx, true);
return 0;
}
static int hnbgw_rx_hnb_register_req(struct hnb_context *ctx, ANY_t *in)
{
+ struct hnb_context *hnb;
HNBRegisterRequestIEs_t ies;
int rc;
@@ -387,6 +428,20 @@
ctx->id.cid = asn1bitstr_to_u28(&ies.cellIdentity);
gsm48_mcc_mnc_from_bcd(ies.plmNidentity.buf, &ctx->id.mcc, &ctx->id.mnc);
+ llist_for_each_entry(hnb, &ctx->gw->hnb_list, list) {
+ if (hnb->hnb_registered && ctx != hnb && memcmp(&ctx->id, &hnb->id, sizeof(ctx->id)) == 0) {
+ struct osmo_fd *ofd = osmo_stream_srv_get_ofd(ctx->conn);
+ char *name = osmo_sock_get_name(ctx, ofd->fd);
+ LOGP(DHNBAP, LOGL_ERROR, "rejecting HNB-REGISTER-REQ with duplicate cell identity "
+ "MCC=%u,MNC=%u,LAC=%u,RAC=%u,SAC=%u,CID=%u from %s\n",
+ ctx->id.mcc, ctx->id.mnc, ctx->id.lac, ctx->id.rac, ctx->id.sac, ctx->id.cid, name);
+ talloc_free(name);
+ return hnbgw_tx_hnb_register_rej(ctx);
+ }
+ }
+
+ ctx->hnb_registered = true;
+
DEBUGP(DHNBAP, "HNB-REGISTER-REQ from %s\n", ctx->identity_info);
/* Send HNBRegisterAccept */