gprs_ns2: add gprs_ns2_ip_vc_local() return the local sockaddr

Change-Id: I65a739772596015b90473045d32d4934d924e43f

include/osmocom/gprs/gprs_ns2.h

@@ -140,6 +140,7 @@ int gprs_ns2_ip_connect_sns(struct gprs_ns2_vc_bind *bind,
 			    uint16_t nsei);
 
 const struct osmo_sockaddr *gprs_ns2_ip_vc_remote(struct gprs_ns2_vc *nsvc);
+const struct osmo_sockaddr *gprs_ns2_ip_vc_local(const struct gprs_ns2_vc *nsvc);
 const struct osmo_sockaddr *gprs_ns2_ip_bind_sockaddr(struct gprs_ns2_vc_bind *bind);
 int gprs_ns2_is_ip_bind(struct gprs_ns2_vc_bind *bind);
 int gprs_ns2_ip_bind_set_dscp(struct gprs_ns2_vc_bind *bind, int dscp);

src/gb/gprs_ns2_udp.c

@@ -393,6 +393,23 @@ struct gprs_ns2_vc *gprs_ns2_ip_bind_connect(struct gprs_ns2_vc_bind *bind,
 	return nsvc;
 }
 
+/*! Return the socket address of the local peer of a NS-VC.
+ *  \param[in] nsvc NS-VC whose local peer we want to know
+ *  \return address of the local peer; NULL in case of error */
+const struct osmo_sockaddr *gprs_ns2_ip_vc_local(const struct gprs_ns2_vc *nsvc)
+{
+	struct priv_bind *priv;
+
+	if (nsvc->ll != GPRS_NS_LL_UDP)
+		return NULL;
+
+	if (nsvc->bind->driver != &vc_driver_ip)
+		return NULL;
+
+	priv = nsvc->bind->priv;
+	return &priv->addr;
+}
+
 /*! Return the socket address of the remote peer of a NS-VC.
  *  \param[in] nsvc NS-VC whose remote peer we want to know
  *  \return address of the remote peer; NULL in case of error */

src/gb/libosmogb.map

@@ -93,6 +93,7 @@ gprs_ns2_ip_connect;
 gprs_ns2_ip_connect2;
 gprs_ns2_ip_connect_inactive;
 gprs_ns2_ip_connect_sns;
+gprs_ns2_ip_vc_local;
 gprs_ns2_ip_vc_remote;
 gprs_ns2_is_frgre_bind;
 gprs_ns2_is_ip_bind;