From 0e8b7ee01d413fe103eb1529927ee154ccb52e77 Mon Sep 17 00:00:00 2001
From: Alexander Couzens <lynxis@fe80.eu>
Date: Sun, 18 Feb 2024 17:55:49 +0100
Subject: [PATCH] osmo-epdg: UE: save apn in the UE object

---
 .../plugins/osmo_epdg/osmo_epdg_db.c          | 11 ++++++++-
 .../plugins/osmo_epdg/osmo_epdg_ue.c          | 23 ++++++++++++++++++-
 .../plugins/osmo_epdg/osmo_epdg_ue.h          |  7 +++++-
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/src/libcharon/plugins/osmo_epdg/osmo_epdg_db.c b/src/libcharon/plugins/osmo_epdg/osmo_epdg_db.c
index c5c68df9d..a962902ad 100644
--- a/src/libcharon/plugins/osmo_epdg/osmo_epdg_db.c
+++ b/src/libcharon/plugins/osmo_epdg/osmo_epdg_db.c
@@ -22,6 +22,8 @@
 #include <threading/rwlock.h>
 #include <unistd.h>
 
+#include <osmocom/gsm/apn.h>
+
 #include "osmo_epdg_plugin.h"
 #include "osmo_epdg_db.h"
 #include "osmo_epdg_utils.h"
@@ -53,6 +55,7 @@ METHOD(osmo_epdg_db_t, create_subscriber, osmo_epdg_ue_t *,
 {
 	osmo_epdg_ue_t *ue;
 	char imsi[16] = {0};
+	char apn[APN_MAXLEN];
 	uint32_t unique = ike_sa->get_unique_id(ike_sa);
 
 	if (epdg_get_imsi_ike(ike_sa, imsi, sizeof(imsi) - 1))
@@ -60,6 +63,12 @@ METHOD(osmo_epdg_db_t, create_subscriber, osmo_epdg_ue_t *,
 		return NULL;
 	}
 
+	if (epdg_get_apn(ike_sa, apn, APN_MAXLEN))
+	{
+		DBG1(DBG_NET, "epdg: get_quintuplet: Can't get APN.");
+		return FALSE;
+	}
+
 	this->lock->write_lock(this->lock);
 	ue = this->subscribers_imsi->remove(this->subscribers_imsi, imsi);
 	if (ue)
@@ -68,7 +77,7 @@ METHOD(osmo_epdg_db_t, create_subscriber, osmo_epdg_ue_t *,
 		ue->put(ue);
 	}
 
-	ue = osmo_epdg_ue_create(unique, imsi);
+	ue = osmo_epdg_ue_create(unique, imsi, apn);
 	if (!ue)
 	{
 		DBG1(DBG_NET, "epdg_db: failed to create UE!");
diff --git a/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.c b/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.c
index d71c4acb8..ee8a01c99 100644
--- a/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.c
+++ b/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.c
@@ -24,6 +24,7 @@
 #include <utils/debug.h>
 
 #include "osmo_epdg_ue.h"
+#include "osmo_epdg_utils.h"
 
 typedef struct private_osmo_epdg_ue_t private_osmo_epdg_ue_t;
 
@@ -48,6 +49,11 @@ struct private_osmo_epdg_ue_t {
 	 */
 	char *imsi;
 
+	/**
+	 * APN encoded as character (foo.example)
+	 */
+	char *apn;
+
 	/**
 	 * IP address of the client. Might become a llist_t in the future
 	 */
@@ -73,6 +79,12 @@ METHOD(osmo_epdg_ue_t, get_imsi, const char *,
 	return this->imsi;
 }
 
+METHOD(osmo_epdg_ue_t, get_apn, const char *,
+       private_osmo_epdg_ue_t *this)
+{
+	return this->apn;
+}
+
 METHOD(osmo_epdg_ue_t, set_address, void,
        private_osmo_epdg_ue_t *this, host_t *address)
 {
@@ -140,18 +152,26 @@ METHOD(osmo_epdg_ue_t, destroy, void,
        private_osmo_epdg_ue_t *this)
 {
 	this->lock->destroy(this->lock);
+	free(this->apn);
 	free(this->imsi);
 	free(this);
 }
 
-osmo_epdg_ue_t *osmo_epdg_ue_create(uint32_t id, const char *imsi)
+osmo_epdg_ue_t *osmo_epdg_ue_create(uint32_t id, const char *imsi, const char *apn)
 {
 	private_osmo_epdg_ue_t *this;
 
+	if (epdg_validate_apn(apn) ||
+	    epdg_validate_imsi(imsi))
+	{
+		return NULL;
+	}
+
 	INIT(this,
 	     .public = {
 		 .get = _get,
 		 .put = _put,
+		 .get_apn = _get_apn,
 		 .get_imsi = _get_imsi,
 		 .get_address = _get_address,
 		 .set_address = _set_address,
@@ -159,6 +179,7 @@ osmo_epdg_ue_t *osmo_epdg_ue_create(uint32_t id, const char *imsi)
 		 .set_state = _set_state,
 		 .destroy = _destroy,
 	     },
+	     .apn = strdup(apn),
 	     .imsi = strdup(imsi),
 	     .id = id,
 	     .lock = rwlock_create(RWLOCK_TYPE_DEFAULT),
diff --git a/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.h b/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.h
index 8c645d6ec..ea29f1178 100644
--- a/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.h
+++ b/src/libcharon/plugins/osmo_epdg/osmo_epdg_ue.h
@@ -55,6 +55,11 @@ enum osmo_epdg_ue_state {
  * UE object
  */
 struct osmo_epdg_ue_t {
+	/**
+	 * Get APN
+	 */
+	const char *(*get_apn)(osmo_epdg_ue_t *this);
+
 	/**
 	 * Get IMSI
 	 */
@@ -103,6 +108,6 @@ struct osmo_epdg_ue_t {
  * Create a osmo_epdg_ue instance.
  * A newly created object will come with refcount = 1. Use put() to destroy it.
  */
-osmo_epdg_ue_t *osmo_epdg_ue_create(uint32_t id, const char *imsi);
+osmo_epdg_ue_t *osmo_epdg_ue_create(uint32_t id, const char *imsi, const char *apn);
 
 #endif /* OSMO_EPDG_UE_H_ */