1 files changed, 279 insertions, 0 deletions
diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c
new file mode 100644
index 000000000000..23932f9b85ec
--- /dev/null
+++ b/net/batman-adv/bat_v_ogm.c
@@ -0,0 +1,279 @@
+/* Copyright (C) 2013-2016 B.A.T.M.A.N. contributors:
+ *
+ * Antonio Quartulli
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "bat_v_ogm.h"
+#include "main.h"
+
+#include <linux/atomic.h>
+#include <linux/byteorder/generic.h>
+#include <linux/errno.h>
+#include <linux/etherdevice.h>
+#include <linux/fs.h>
+#include <linux/if_ether.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/random.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/stddef.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+#include "hard-interface.h"
+#include "packet.h"
+#include "routing.h"
+#include "send.h"
+#include "translation-table.h"
+
+/**
+ * batadv_v_ogm_start_timer - restart the OGM sending timer
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+static void batadv_v_ogm_start_timer(struct batadv_priv *bat_priv)
+{
+	unsigned long msecs;
+	/* this function may be invoked in different contexts (ogm rescheduling
+	 * or hard_iface activation), but the work timer should not be reset
+	 */
+	if (delayed_work_pending(&bat_priv->bat_v.ogm_wq))
+		return;
+
+	msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
+	msecs += prandom_u32() % (2 * BATADV_JITTER);
+	queue_delayed_work(batadv_event_workqueue, &bat_priv->bat_v.ogm_wq,
+			   msecs_to_jiffies(msecs));
+}
+
+/**
+ * batadv_v_ogm_send_to_if - send a batman ogm using a given interface
+ * @skb: the OGM to send
+ * @hard_iface: the interface to use to send the OGM
+ */
+static void batadv_v_ogm_send_to_if(struct sk_buff *skb,
+				    struct batadv_hard_iface *hard_iface)
+{
+	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+
+	if (hard_iface->if_status != BATADV_IF_ACTIVE)
+		return;
+
+	batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
+	batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
+			   skb->len + ETH_HLEN);
+
+	batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
+}
+
+/**
+ * batadv_v_ogm_send - periodic worker broadcasting the own OGM
+ * @work: work queue item
+ */
+static void batadv_v_ogm_send(struct work_struct *work)
+{
+	struct batadv_hard_iface *hard_iface;
+	struct batadv_priv_bat_v *bat_v;
+	struct batadv_priv *bat_priv;
+	struct batadv_ogm2_packet *ogm_packet;
+	struct sk_buff *skb, *skb_tmp;
+	unsigned char *ogm_buff, *pkt_buff;
+	int ogm_buff_len;
+	u16 tvlv_len = 0;
+
+	bat_v = container_of(work, struct batadv_priv_bat_v, ogm_wq.work);
+	bat_priv = container_of(bat_v, struct batadv_priv, bat_v);
+
+	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
+		goto out;
+
+	ogm_buff = bat_priv->bat_v.ogm_buff;
+	ogm_buff_len = bat_priv->bat_v.ogm_buff_len;
+	/* tt changes have to be committed before the tvlv data is
+	 * appended as it may alter the tt tvlv container
+	 */
+	batadv_tt_local_commit_changes(bat_priv);
+	tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, &ogm_buff,
+						    &ogm_buff_len,
+						    BATADV_OGM2_HLEN);
+
+	bat_priv->bat_v.ogm_buff = ogm_buff;
+	bat_priv->bat_v.ogm_buff_len = ogm_buff_len;
+
+	skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + ogm_buff_len);
+	if (!skb)
+		goto reschedule;
+
+	skb_reserve(skb, ETH_HLEN);
+	pkt_buff = skb_put(skb, ogm_buff_len);
+	memcpy(pkt_buff, ogm_buff, ogm_buff_len);
+
+	ogm_packet = (struct batadv_ogm2_packet *)skb->data;
+	ogm_packet->seqno = htonl(atomic_read(&bat_priv->bat_v.ogm_seqno));
+	atomic_inc(&bat_priv->bat_v.ogm_seqno);
+	ogm_packet->tvlv_len = htons(tvlv_len);
+
+	/* broadcast on every interface */
+	rcu_read_lock();
+	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+		if (hard_iface->soft_iface != bat_priv->soft_iface)
+			continue;
+
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "Sending own OGM2 packet (originator %pM, seqno %u, throughput %u, TTL %d) on interface %s [%pM]\n",
+			   ogm_packet->orig, ntohl(ogm_packet->seqno),
+			   ntohl(ogm_packet->throughput), ogm_packet->ttl,
+			   hard_iface->net_dev->name,
+			   hard_iface->net_dev->dev_addr);
+
+		/* this skb gets consumed by batadv_v_ogm_send_to_if() */
+		skb_tmp = skb_clone(skb, GFP_ATOMIC);
+		if (!skb_tmp)
+			break;
+
+		batadv_v_ogm_send_to_if(skb_tmp, hard_iface);
+	}
+	rcu_read_unlock();
+
+	consume_skb(skb);
+
+reschedule:
+	batadv_v_ogm_start_timer(bat_priv);
+out:
+	return;
+}
+
+/**
+ * batadv_v_ogm_iface_enable - prepare an interface for B.A.T.M.A.N. V
+ * @hard_iface: the interface to prepare
+ *
+ * Takes care of scheduling own OGM sending routine for this interface.
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int batadv_v_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
+{
+	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+
+	batadv_v_ogm_start_timer(bat_priv);
+
+	return 0;
+}
+
+/**
+ * batadv_v_ogm_primary_iface_set - set a new primary interface
+ * @primary_iface: the new primary interface
+ */
+void batadv_v_ogm_primary_iface_set(struct batadv_hard_iface *primary_iface)
+{
+	struct batadv_priv *bat_priv = netdev_priv(primary_iface->soft_iface);
+	struct batadv_ogm2_packet *ogm_packet;
+
+	if (!bat_priv->bat_v.ogm_buff)
+		return;
+
+	ogm_packet = (struct batadv_ogm2_packet *)bat_priv->bat_v.ogm_buff;
+	ether_addr_copy(ogm_packet->orig, primary_iface->net_dev->dev_addr);
+}
+
+/**
+ * batadv_v_ogm_packet_recv - OGM2 receiving handler
+ * @skb: the received OGM
+ * @if_incoming: the interface where this OGM has been received
+ *
+ * Return: NET_RX_SUCCESS and consume the skb on success or returns NET_RX_DROP
+ * (without freeing the skb) on failure
+ */
+int batadv_v_ogm_packet_recv(struct sk_buff *skb,
+			     struct batadv_hard_iface *if_incoming)
+{
+	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
+	struct batadv_ogm2_packet *ogm_packet;
+	struct ethhdr *ethhdr = eth_hdr(skb);
+
+	/* did we receive a OGM2 packet on an interface that does not have
+	 * B.A.T.M.A.N. V enabled ?
+	 */
+	if (strcmp(bat_priv->bat_algo_ops->name, "BATMAN_V") != 0)
+		return NET_RX_DROP;
+
+	if (!batadv_check_management_packet(skb, if_incoming, BATADV_OGM2_HLEN))
+		return NET_RX_DROP;
+
+	if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
+		return NET_RX_DROP;
+
+	ogm_packet = (struct batadv_ogm2_packet *)skb->data;
+
+	if (batadv_is_my_mac(bat_priv, ogm_packet->orig))
+		return NET_RX_DROP;
+
+	batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
+	batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
+			   skb->len + ETH_HLEN);
+
+	consume_skb(skb);
+	return NET_RX_SUCCESS;
+}
+
+/**
+ * batadv_v_ogm_init - initialise the OGM2 engine
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: 0 on success or a negative error code in case of failure
+ */
+int batadv_v_ogm_init(struct batadv_priv *bat_priv)
+{
+	struct batadv_ogm2_packet *ogm_packet;
+	unsigned char *ogm_buff;
+	u32 random_seqno;
+
+	bat_priv->bat_v.ogm_buff_len = BATADV_OGM2_HLEN;
+	ogm_buff = kzalloc(bat_priv->bat_v.ogm_buff_len, GFP_ATOMIC);
+	if (!ogm_buff)
+		return -ENOMEM;
+
+	bat_priv->bat_v.ogm_buff = ogm_buff;
+	ogm_packet = (struct batadv_ogm2_packet *)ogm_buff;
+	ogm_packet->packet_type = BATADV_OGM2;
+	ogm_packet->version = BATADV_COMPAT_VERSION;
+	ogm_packet->ttl = BATADV_TTL;
+	ogm_packet->flags = BATADV_NO_FLAGS;
+	ogm_packet->throughput = htonl(BATADV_THROUGHPUT_MAX_VALUE);
+
+	/* randomize initial seqno to avoid collision */
+	get_random_bytes(&random_seqno, sizeof(random_seqno));
+	atomic_set(&bat_priv->bat_v.ogm_seqno, random_seqno);
+	INIT_DELAYED_WORK(&bat_priv->bat_v.ogm_wq, batadv_v_ogm_send);
+
+	return 0;
+}
+
+/**
+ * batadv_v_ogm_free - free OGM private resources
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+void batadv_v_ogm_free(struct batadv_priv *bat_priv)
+{
+	cancel_delayed_work_sync(&bat_priv->bat_v.ogm_wq);
+
+	kfree(bat_priv->bat_v.ogm_buff);
+	bat_priv->bat_v.ogm_buff = NULL;
+	bat_priv->bat_v.ogm_buff_len = 0;
+}