netdev - [RFC v2 09/19] batman-adv: Add distributed_arp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20181123161359.13342-10-sven@narfation.org>
Date:   Fri, 23 Nov 2018 17:13:49 +0100
From:   Sven Eckelmann <sven@...fation.org>
To:     b.a.t.m.a.n@...ts.open-mesh.org
Cc:     Jiri Pirko <jiri@...lanox.com>, netdev@...r.kernel.org,
        Sven Eckelmann <sven@...fation.org>
Subject: [RFC v2 09/19] batman-adv: Add distributed_arp_table mesh genl configuration

The mesh interface can use a distributed hash table to answer ARP requests
without flooding the request through the whole mesh.

The BATADV_CMD_SET_MESH/BATADV_CMD_GET_MESH commands allow to set/get the
configuration of this feature using the BATADV_ATTR_DISTRIBUTED_ARP_TABLE
attribute. Setting the u8 to zero will disable this feature and setting it
to something else is enabling this feature.

Cc: Jiri Pirko <jiri@...lanox.com>
Signed-off-by: Sven Eckelmann <sven@...fation.org>
---
 include/uapi/linux/batman_adv.h |  8 ++++++++
 net/batman-adv/netlink.c        | 17 +++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h
index 711379ef..618c727c 100644
--- a/include/uapi/linux/batman_adv.h
+++ b/include/uapi/linux/batman_adv.h
@@ -387,6 +387,14 @@ enum batadv_nl_attrs {
 	 */
 	BATADV_ATTR_BRIDGE_LOOP_AVOIDANCE,
 
+	/**
+	 * @BATADV_ATTR_DISTRIBUTED_ARP_TABLE: whether the distributed arp table
+	 *  feature is enabled. This feature uses a distributed hash table to
+	 *  answer ARP requests without flooding the request through the whole
+	 *  mesh.
+	 */
+	BATADV_ATTR_DISTRIBUTED_ARP_TABLE,
+
 	/* add attributes above here, update the policy in netlink.c */
 
 	/**
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 95181808..d93039b2 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -145,6 +145,7 @@ static const struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
 	[BATADV_ATTR_ISOLATION_MASK]		= { .type = NLA_U32 },
 	[BATADV_ATTR_BONDING]			= { .type = NLA_U8 },
 	[BATADV_ATTR_BRIDGE_LOOP_AVOIDANCE]	= { .type = NLA_U8 },
+	[BATADV_ATTR_DISTRIBUTED_ARP_TABLE]	= { .type = NLA_U8 },
 };
 
 /**
@@ -290,6 +291,12 @@ static int batadv_netlink_mesh_put(struct sk_buff *msg,
 		goto nla_put_failure;
 #endif /* CONFIG_BATMAN_ADV_BLA */
 
+#ifdef CONFIG_BATMAN_ADV_DAT
+	if (nla_put_u8(msg, BATADV_ATTR_DISTRIBUTED_ARP_TABLE,
+		       !!atomic_read(&bat_priv->distributed_arp_table)))
+		goto nla_put_failure;
+#endif /* CONFIG_BATMAN_ADV_DAT */
+
 	batadv_hardif_put(primary_if);
 
 	genlmsg_end(msg, hdr);
@@ -413,6 +420,16 @@ static int batadv_netlink_set_mesh(struct sk_buff *skb, struct genl_info *info)
 	}
 #endif /* CONFIG_BATMAN_ADV_BLA */
 
+#ifdef CONFIG_BATMAN_ADV_DAT
+	if (info->attrs[BATADV_ATTR_DISTRIBUTED_ARP_TABLE]) {
+		attr = info->attrs[BATADV_ATTR_DISTRIBUTED_ARP_TABLE];
+
+		atomic_set(&bat_priv->distributed_arp_table,
+			   !!nla_get_u8(attr));
+		batadv_dat_status_update(bat_priv->soft_iface);
+	}
+#endif /* CONFIG_BATMAN_ADV_DAT */
+
 	batadv_netlink_notify_mesh(bat_priv);
 
 	return 0;
-- 
2.19.1