gbproxy: Forward MS_REGISTR_ENQ/_RESP correctly
We need to save the BSS NSE <-> IMSI mapping to correctly route the
answer.
Related: OS#4472
Change-Id: I1908bbe8db11271dbd3f45b0d9f1bc0bfe48f239
diff --git a/src/gb_proxy.c b/src/gb_proxy.c
index e017abe..94ac4a3 100644
--- a/src/gb_proxy.c
+++ b/src/gb_proxy.c
@@ -1114,6 +1114,26 @@
rc = gbprox_relay2nse(msg, nse, 0);
break;
}
+ case BSSGP_PDUT_MS_REGISTR_ENQ:
+ {
+ struct gbproxy_sgsn *sgsn;
+ struct osmo_mobile_identity mi;
+ const uint8_t *mi_data = TLVP_VAL(&tp[0], BSSGP_IE_IMSI);
+ uint8_t mi_len = TLVP_LEN(&tp[0], BSSGP_IE_IMSI);
+ osmo_mobile_identity_decode(&mi, mi_data, mi_len, false);
+
+ sgsn = gbproxy_select_sgsn(nse->cfg, NULL);
+ if (!sgsn) {
+ LOGP(DGPRS, LOGL_ERROR, "Could not find any SGSN, dropping message!\n");
+ rc = -EINVAL;
+ break;
+ }
+
+ gbproxy_imsi_cache_update(nse, mi.imsi, CACHE_USAGE_MS_REG_ENQ);
+
+ rc = gbprox_relay2nse(msg, sgsn->nse, 0);
+ break;
+ }
default:
LOGPNSE(nse, LOGL_ERROR, "Rx %s: Implementation missing\n", pdut_name);
break;
@@ -1444,6 +1464,25 @@
case BSSGP_PDUT_RAN_INFO_APP_ERROR:
rc = gbprox_rx_rim_from_sgsn(tp, nse, msg, log_pfx, pdut_name);
break;
+ case BSSGP_PDUT_MS_REGISTR_ENQ_RESP:
+ {
+ struct gbproxy_nse *nse_peer;
+ struct osmo_mobile_identity mi;
+ const uint8_t *mi_data = TLVP_VAL(&tp[0], BSSGP_IE_IMSI);
+ uint8_t mi_len = TLVP_LEN(&tp[0], BSSGP_IE_IMSI);
+ osmo_mobile_identity_decode(&mi, mi_data, mi_len, false);
+ nse_peer = gbproxy_nse_by_imsi(cfg, mi.imsi, CACHE_USAGE_MS_REG_ENQ);
+ if (!nse_peer) {
+ LOGPNSE(nse, LOGL_ERROR, "Rx %s: Cannot find NSE\n", pdut_name);
+ return tx_status(nse, ns_bvci, BSSGP_CAUSE_INV_MAND_INF, NULL, msg);
+ } else if (nse_peer->sgsn_facing) {
+ LOGPNSE(nse, LOGL_ERROR, "Forwarding %s failed: IMSI cache contains SGSN NSE", pdut_name);
+ return tx_status(nse, ns_bvci, BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, msg);
+ }
+ gbproxy_imsi_cache_remove(cfg, mi.imsi, CACHE_USAGE_MS_REG_ENQ);
+ gbprox_relay2nse(msg, nse_peer, ns_bvci);
+ break;
+ }
default:
LOGPNSE(nse, LOGL_NOTICE, "Rx %s: Not supported\n", pdut_name);
rate_ctr_inc(rate_ctr_group_get_ctr(cfg->ctrg, GBPROX_GLOB_CTR_PROTO_ERR_SGSN));