osmo-epdg: implement Tunnel Request/Response

Requires gsup message types in libosmocore

src/libcharon/plugins/osmo_epdg/gsup_client.c

@@ -194,6 +194,47 @@ static bool enqueue(private_osmo_epdg_gsup_client_t *this, gsup_request_t *req,
 	return ret;
 }
 
+METHOD(osmo_epdg_gsup_client_t, tunnel_request, osmo_epdg_gsup_response_t*,
+        private_osmo_epdg_gsup_client_t *this, char *imsi, char *apn)
+{
+	struct osmo_gsup_message gsup_msg = {0};
+	struct msgb *msg;
+	bool timedout;
+
+	DBG1(DBG_NET, "Tunnel Request Request for %s", imsi);
+	gsup_msg.message_type = OSMO_GSUP_MSGT_EPDG_TUNNEL_REQUEST;
+	gsup_msg.current_rat_type = OSMO_RAT_EUTRAN_SGS;
+
+	if (!imsi || strlen(imsi) == 0)
+	{
+		/* TODO: inval imsi! */
+		return NULL;
+	}
+	strncpy(gsup_msg.imsi, imsi, sizeof(gsup_msg.imsi));
+
+	msg = encode_to_msgb(&gsup_msg);
+	if (!msg)
+	{
+		DBG1(DBG_NET, "Couldn't alloc/encode gsup message.");
+		return NULL;
+	}
+
+	/* TODO: add APN! */
+	gsup_request_t *req = gsup_request_create(OSMO_GSUP_MSGT_SEND_AUTH_INFO_REQUEST, msg);
+	osmo_epdg_gsup_response_t *resp = NULL;
+	timedout = enqueue(this, req, 5000);
+	if (timedout)
+	{
+		gsup_request_destroy(this, req);
+		return NULL;
+	}
+
+	resp = req->resp;
+	req->resp = NULL;
+	gsup_request_destroy(this, req);
+	return ret;
+}
+
 METHOD(osmo_epdg_gsup_client_t, send_auth_request, osmo_epdg_gsup_response_t*,
         private_osmo_epdg_gsup_client_t *this, char *imsi, uint8_t cn_domain, chunk_t *auts, chunk_t *auts_rand)
 {
@@ -489,6 +530,7 @@ osmo_epdg_gsup_client_t *osmo_epdg_gsup_client_create(char *uri)
 			.public = {
 				.send_auth_request = _send_auth_request,
 				.update_location = _update_location,
+				.tunnel_request = _tunnel_request,
 				.destroy = _destroy,
 			},
 			.uri = strdup(uri),

src/libcharon/plugins/osmo_epdg/gsup_client.h

@@ -61,6 +61,14 @@ struct osmo_epdg_gsup_client_t {
 			char *imsi,
 			uint8_t cn_domain);
 
+	/**
+	 * Tunnel Request
+	 *
+	 * @return		NULL or the osmo_gsup_message
+	 */
+	osmo_epdg_gsup_response_t *(*tunnel_request)(osmo_epdg_gsup_client_t *this,
+			char *imsi, char *apn);
+
 	/**
 	 * Destroy a osmo_epdg_gsup_client_t.
 	 */

src/libcharon/plugins/osmo_epdg/osmo_epdg_listener.c

@@ -89,12 +89,34 @@ METHOD(listener_t, authorize, bool,
                 ike_sa->get_name(ike_sa),
 		final,
 		ike_sa->has_condition(ike_sa, COND_EAP_AUTHENTICATED));
-	
-	sleep(1);
-	if (final)
+
+	if (!final)
 	{
-		/* TODO: create new Tunnel and save Tunnel information locally */
+		return TRUE;
 	}
+
+	osmo_epdg_gsup_response_t *resp = this->gsup->tunnel_request(this->gsup, imsi, apn);
+	if (!resp)
+	{
+		DBG1(DBG_NET, "epdg: GSUP: couldn't send Tunnel Requeset.");
+		goto err;
+	}
+
+	if (resp->gsup.message_type == OSMO_GSUP_MSGT_EPDG_TUNNEL_ERROR)
+	{
+		DBG1(DBG_NET, "epdg_listener: Tunnel Error! Cause: %02x", resp->gsup.cause);
+		goto err;
+	}
+	else if (resp->gsup.message_type != OSMO_GSUP_MSGT_EPDG_TUNNEL_RESULT)
+	{
+		DBG1(DBG_NET, "epdg_listener: Tunnel unexpected message type: %02x", resp->gsup.message_type);
+		goto err;
+	}
+
+	return TRUE;
+err:
+	*success = FALSE;
+	/* keep still subscribed */
 	return TRUE;
 }
 

src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.c

@@ -19,6 +19,7 @@
 #include <errno.h>
 
 #include <osmocom/core/msgb.h>
+#include <sa/ike_sa.h>
 #include <utils/utils.h>
 #include <utils/debug.h>
 
@@ -63,3 +64,24 @@ int get_imsi(identification_t *id, char *imsi, size_t imsi_len)
 	strncpy(imsi, nai.ptr + 1, min(15, imsi_len));
 	return 0;
 }
+
+int get_apn(ike_sa_t *sa, char *apn, size_t apn_len)
+{
+	identification_t* apn_id;
+	chunk_t apn_chunk;
+
+	apn_id = sa->get_my_id(sa);
+	if (!apn_id)
+	{
+		return -EINVAL;
+	}
+
+	apn_chunk = apn_id->get_encoding(apn_id);
+	if (apn_chunk.len >= apn_len)
+	{
+		return -ENOMEM;
+	}
+
+	strncpy(apn, apn_chunk.ptr, apn_len);
+	return -1;
+}

src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.h

@@ -17,6 +17,7 @@
  */
 
 #include <osmocom/core/msgb.h>
+#include <sa/ike_sa.h>
 #include <utils/chunk.h>
 #include <utils/identification.h>
 
@@ -25,3 +26,4 @@
 
 struct msgb *chunk_to_msgb(chunk_t *chunk);
 int get_imsi(identification_t *id, char *imsi, size_t imsi_len);
+int get_apn(ike_sa_t *sa, char *apn, size_t apn_len);