batman-adv: implement AP-isolation on the receiver side

When a node receives a unicast packet it checks if the source and the
destination client can communicate or not due to the AP isolation

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

5 files changed, 50 insertions, 0 deletions

diff --git a/net/batman-adv/bat_sysfs.c b/net/batman-adv/bat_sysfs.c
index cd15deba60a1..b8a7414c3571 100644
--- a/net/batman-adv/bat_sysfs.c
+++ b/net/batman-adv/bat_sysfs.c
@@ -380,6 +380,7 @@ static ssize_t store_gw_bwidth(struct kobject *kobj, struct attribute *attr,
 BAT_ATTR_BOOL(aggregated_ogms, S_IRUGO | S_IWUSR, NULL);
 BAT_ATTR_BOOL(bonding, S_IRUGO | S_IWUSR, NULL);
 BAT_ATTR_BOOL(fragmentation, S_IRUGO | S_IWUSR, update_min_mtu);
+BAT_ATTR_BOOL(ap_isolation, S_IRUGO | S_IWUSR, NULL);
 static BAT_ATTR(vis_mode, S_IRUGO | S_IWUSR, show_vis_mode, store_vis_mode);
 static BAT_ATTR(gw_mode, S_IRUGO | S_IWUSR, show_gw_mode, store_gw_mode);
 BAT_ATTR_UINT(orig_interval, S_IRUGO | S_IWUSR, 2 * JITTER, INT_MAX, NULL);
@@ -396,6 +397,7 @@ static struct bat_attribute *mesh_attrs[] = {
         &bat_attr_aggregated_ogms,
         &bat_attr_bonding,
         &bat_attr_fragmentation,
+        &bat_attr_ap_isolation,
         &bat_attr_vis_mode,
         &bat_attr_gw_mode,
         &bat_attr_orig_interval,
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 6deed44a3703..9addbab52999 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -739,6 +739,9 @@ void interface_rx(struct net_device *soft_iface,
 
         soft_iface->last_rx = jiffies;
 
+        if (is_ap_isolated(bat_priv, ethhdr->h_source, ethhdr->h_dest))
+                goto dropped;
+
         netif_rx(skb);
         goto out;
 
@@ -812,6 +815,7 @@ struct net_device *softif_create(const char *name)
 
         atomic_set(&bat_priv->aggregated_ogms, 1);
         atomic_set(&bat_priv->bonding, 0);
+        atomic_set(&bat_priv->ap_isolation, 0);
         atomic_set(&bat_priv->vis_mode, VIS_TYPE_CLIENT_UPDATE);
         atomic_set(&bat_priv->gw_mode, GW_MODE_OFF);
         atomic_set(&bat_priv->gw_sel_class, 20);
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index d6305645e08d..d0ed931ad2e7 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -781,6 +781,18 @@ static void tt_global_table_free(struct bat_priv *bat_priv)
         bat_priv->tt_global_hash = NULL;
 }
 
+static bool _is_ap_isolated(struct tt_local_entry *tt_local_entry,
+                            struct tt_global_entry *tt_global_entry)
+{
+        bool ret = false;
+
+        if (tt_local_entry->flags & TT_CLIENT_WIFI &&
+            tt_global_entry->flags & TT_CLIENT_WIFI)
+                ret = true;
+
+        return ret;
+}
+
 struct orig_node *transtable_search(struct bat_priv *bat_priv,
                                     const uint8_t *addr)
 {
@@ -1729,3 +1741,33 @@ void tt_commit_changes(struct bat_priv *bat_priv)
         atomic_inc(&bat_priv->ttvn);
         bat_priv->tt_poss_change = false;
 }
+
+bool is_ap_isolated(struct bat_priv *bat_priv, uint8_t *src, uint8_t *dst)
+{
+        struct tt_local_entry *tt_local_entry = NULL;
+        struct tt_global_entry *tt_global_entry = NULL;
+        bool ret = true;
+
+        if (!atomic_read(&bat_priv->ap_isolation))
+                return false;
+
+        tt_local_entry = tt_local_hash_find(bat_priv, dst);
+        if (!tt_local_entry)
+                goto out;
+
+        tt_global_entry = tt_global_hash_find(bat_priv, src);
+        if (!tt_global_entry)
+                goto out;
+
+        if (_is_ap_isolated(tt_local_entry, tt_global_entry))
+                goto out;
+
+        ret = false;
+
+out:
+        if (tt_global_entry)
+                tt_global_entry_free_ref(tt_global_entry);
+        if (tt_local_entry)
+                tt_local_entry_free_ref(tt_local_entry);
+        return ret;
+}
diff --git a/net/batman-adv/translation-table.h b/net/batman-adv/translation-table.h
index 4d1ca35c6818..f1d148ef0e36 100644
--- a/net/batman-adv/translation-table.h
+++ b/net/batman-adv/translation-table.h
@@ -63,5 +63,6 @@ void handle_tt_response(struct bat_priv *bat_priv,
 void send_roam_adv(struct bat_priv *bat_priv, uint8_t *client,
                    struct orig_node *orig_node);
 void tt_commit_changes(struct bat_priv *bat_priv);
+bool is_ap_isolated(struct bat_priv *bat_priv, uint8_t *src, uint8_t *dst);
 
 #endif /* _NET_BATMAN_ADV_TRANSLATION_TABLE_H_ */
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index bd0ced8a9a9e..1ae355750511 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -146,6 +146,7 @@ struct bat_priv {
         atomic_t aggregated_ogms;       /* boolean */
         atomic_t bonding;               /* boolean */
         atomic_t fragmentation;         /* boolean */
+        atomic_t ap_isolation;          /* boolean */
         atomic_t vis_mode;              /* VIS_TYPE_* */
         atomic_t gw_mode;               /* GW_MODE_* */
         atomic_t gw_sel_class;          /* uint */