cn unitdata: verify correct remote addr
When receiving unitdata from the CN, verify that it is indeed coming from the
remote address that matches our CS/PS domain settings.
This patch came from an earlier stage where the is_ps out-parameter was
actually used. While it currently isn't, it doesn't hurt to leave it there.
Change-Id: I7190b4c3a05e8bac0eeffa1eab18c9e47429cb17
diff --git a/src/hnbgw_cn.c b/src/hnbgw_cn.c
index 8124ce5..e967260 100644
--- a/src/hnbgw_cn.c
+++ b/src/hnbgw_cn.c
@@ -240,6 +240,31 @@
return rc;
}
+static bool pc_and_ssn_match(const struct osmo_sccp_addr *a, const struct osmo_sccp_addr *b)
+{
+ return (a == b)
+ || ((a->pc == b->pc)
+ && (a->ssn == b->ssn));
+}
+
+static int classify_cn_remote_addr(const struct hnb_gw *gw,
+ const struct osmo_sccp_addr *cn_remote_addr,
+ bool *is_ps)
+{
+ if (pc_and_ssn_match(cn_remote_addr, &gw->sccp.remote_addr_cs)) {
+ if (is_ps)
+ *is_ps = false;
+ return 0;
+ }
+ if (pc_and_ssn_match(cn_remote_addr, &gw->sccp.remote_addr_ps)) {
+ if (is_ps)
+ *is_ps = true;
+ return 0;
+ }
+ LOGP(DMAIN, LOGL_ERROR, "Unexpected remote address, matches neither CS nor PS address: %s\n",
+ osmo_sccp_addr_dump(cn_remote_addr));
+ return -1;
+}
static int handle_cn_unitdata(struct hnbgw_cnlink *cnlink,
const struct osmo_scu_unitdata_param *param,
@@ -251,6 +276,9 @@
return -1;
}
+ if (classify_cn_remote_addr(cnlink->gw, ¶m->calling_addr, NULL) < 0)
+ return -1;
+
return handle_cn_ranap(cnlink, msgb_l2(oph->msg), msgb_l2len(oph->msg));
}