Start implementing osmo_epdg state

src/libcharon/plugins/osmo_epdg/Makefile.am

@@ -22,4 +22,5 @@ libstrongswan_osmo_epdg_la_SOURCES = \
 	osmo_epdg_listener.h osmo_epdg_listener.c \
 	gsup_client.h gsup_client.c \
 	ipa_client.h ipa_client.c \
-	osmo_epdg_utils.h osmo_epdg_utils.c
+	osmo_epdg_utils.h osmo_epdg_utils.c \
+	osmo_epdg_db.h osmo_epdg_db.c

src/libcharon/plugins/osmo_epdg/osmo_epdg_db.c

@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2023 sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * Author: Alexander Couzens <acouzens@sysmocom.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <daemon.h>
+#include <plugins/plugin.h>
+#include <collections/hashtable.h>
+#include <unistd.h>
+
+#include "osmo_epdg_plugin.h"
+#include "osmo_epdg_db.h"
+#include "osmo_epdg_utils.h"
+
+typedef struct private_osmo_epdg_db_t private_osmo_epdg_db_t;
+
+/**
+ * Private data of an osmo_epdg_db_t object.
+ */
+struct private_osmo_epdg_db_t {
+	/**
+	 * Public osmo_epdg_db_t interface.
+	 */
+	osmo_epdg_db_t public;
+
+	/**
+	 * GSUP client
+	 */
+	osmo_epdg_gsup_client_t *gsup;
+
+	/**
+	 * subscriber hash by ID
+	 */
+	hashtable_t *subscribers;
+
+	/**
+	 * subscriber hash by imsi (how to handle multiple?)
+	 */
+	hashtable_t *subscribers_imsi;
+
+	/**
+	 * subscriber by ike_sa
+	 */
+	hashtable_t *subscribers_ike_sa_t;
+};
+
+METHOD(osmo_epdg_db_t, create_subscriber_imsi, osmo_epdg_ue_t *,
+	private_osmo_epdg_db_t *this, ike_sa_t *ike_sa,
+	char *imsi)
+{
+	return NULL;
+}
+
+METHOD(osmo_epdg_db_t, get_subscriber_imsi, osmo_epdg_ue_t *,
+	private_osmo_epdg_db_t *this, char *imsi, int offset)
+{
+	return NULL;
+}
+
+METHOD(osmo_epdg_db_t, get_subscriber_id, osmo_epdg_ue_t *,
+	private_osmo_epdg_db_t *this, uint32_t id)
+{
+	return NULL;
+}
+
+METHOD(osmo_epdg_db_t, get_subscriber_ike, osmo_epdg_ue_t *,
+	private_osmo_epdg_db_t *this, ike_sa_t *ike_sa)
+{
+	return NULL;
+}
+
+METHOD(osmo_epdg_db_t, destroy_subscriber_id, void,
+	private_osmo_epdg_db_t *this, uint32_t id)
+{
+	return;
+}
+
+METHOD(osmo_epdg_db_t, destroy_subscriber_ike, void,
+	private_osmo_epdg_db_t *this, ike_sa_t *ike_sa)
+{
+	return;
+}
+
+METHOD(osmo_epdg_db_t, destroy_subscriber, void,
+	private_osmo_epdg_db_t *this, osmo_epdg_ue_t *ue)
+{
+	return;
+}
+
+METHOD(osmo_epdg_db_t, destroy, void,
+	private_osmo_epdg_db_t *this)
+{
+	free(this);
+}
+
+/**
+ * See header
+ */
+osmo_epdg_db_t *osmo_epdg_db_create(osmo_epdg_gsup_client_t *gsup)
+{
+	private_osmo_epdg_db_t *this;
+
+	INIT(this,
+		.public = {
+			.create_subscriber = _create_subscriber_imsi,
+			.get_subscriber_id = _get_subscriber_id,
+			.get_subscriber_imsi = _get_subscriber_imsi,
+			.get_subscriber_ike = _get_subscriber_ike,
+			.destroy_subscriber_ike = _destroy_subscriber_ike,
+			.destroy_subscriber_id = _destroy_subscriber_id,
+			.destroy_subscriber = _destroy_subscriber,
+			.destroy = _destroy,
+		},
+	);
+
+	return &this->public;
+}
+

src/libcharon/plugins/osmo_epdg/osmo_epdg_db.h

@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2023 sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * Author: Alexander Couzens <acouzens@sysmocom.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+// TODO: check license
+
+/**
+ * @defgroup osmo_epdg_db osmo_epdg_db
+ * @{ @ingroup osmo_epdg
+ */
+
+#ifndef OSMO_EPDG_DB_H_
+#define OSMO_EPDG_DB_H_
+
+#include <bus/listeners/listener.h>
+#include "gsup_client.h"
+#include "osmo_epdg_utils.h"
+
+typedef struct osmo_epdg_db_t osmo_epdg_db_t;
+
+/**
+ * SIM listener implementation using a set of AKA functions.
+ */
+struct osmo_epdg_db_t {
+	/**
+	 * Create new subscriber by imsi, before sending authentication
+	 */
+	osmo_epdg_ue_t *(*create_subscriber)(osmo_epdg_db_t *this, ike_sa_t *ike_sa, char *imsi);
+
+	/**
+	 * Get subscriber by imsi, there might be multiple UE by this IMSI
+	 */
+	osmo_epdg_ue_t *(*get_subscriber_imsi)(osmo_epdg_db_t *this, char *imsi, int offset);
+
+	/**
+	 * Get subscriber by ike
+	 */
+	osmo_epdg_ue_t *(*get_subscriber_ike)(osmo_epdg_db_t *this, ike_sa_t *ike_sa);
+
+	/**
+	 * Get subscriber by id
+	 */
+	osmo_epdg_ue_t *(*get_subscriber_id)(osmo_epdg_db_t *this, uint32_t id);
+
+	/**
+	 * Destroy subscriber by imsi
+	 */
+	void (*destroy_subscriber_ike)(osmo_epdg_db_t *this, ike_sa_t *ike_sa);
+
+	/**
+	 * Destroy subscriber by imsi
+	 */
+	void (*destroy_subscriber_id)(osmo_epdg_db_t *this, uint32_t id);
+
+	/**
+	 * Destroy subscriber by object
+	 */
+	void (*destroy_subscriber)(osmo_epdg_db_t *this, osmo_epdg_ue_t *ue);
+
+	/**
+	 * Destroy a osmo_epdg_db_t.
+	 */
+	void (*destroy)(osmo_epdg_db_t *this);
+};
+
+/**
+ * Create a osmo_epdg_db instance.
+ */
+osmo_epdg_db_t *osmo_epdg_db_create(osmo_epdg_gsup_client_t *gsup);
+
+#endif /* OSMO_EPDG_DB_H_ */

src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.h

@@ -27,6 +27,35 @@
 
 #define IPA_ALLOC_SIZE 1200
 
+enum ue_state {
+	/* Initial */
+	UE_UNAUTHENTICATED,
+	/* Authenticated */
+	UE_AUTHENTICATED,
+	/* Wait for GSUP Update Location Request */
+	UE_WAIT_LOCATION_UPDATE,
+	/* Wait for GSUP Tunnel Request */
+	UE_WAIT_TUNNEL,
+	/* Everything ready, data can flow */
+	UE_CONNECTED,
+	/* Notify the osmo-epdg about destruction, wait for an answer */
+	UE_DISCONNECTING,
+	UE_DESTROYED,
+};
+
+/* TODO: how to clean up/garbage collect */
+struct osmo_epdg_ue {
+	/* increasing uniq id */
+	uint32_t id;
+	/* imsi should be uniq, need protected against fake UE */
+	char *imsi;
+	enum ue_state state;
+
+	/* TODO: missing strongswan session pointer */
+	ike_sa_t *ike_sa;
+};
+typedef struct osmo_epdg_ue osmo_epdg_ue_t;
+
 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);