[B.A.T.M.A.N.] [PATCH v8 11/14] batman-adv: add B.A.T.M.A.N. Dump BLA claims via netlink

Simon Wunderlich
2016-05-23T15:59:42Z

From: Andrew Lunn <andrew@lunn.ch>

Dump the list of bridge loop avoidance claims via the netlink socket.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[sven.eckelmann@open-mesh.com: add policy for attributes, fix includes, fix
soft_iface reference leak]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
[sw@simonwunderlich.de: fix kerneldoc, fix error reporting]
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
include/uapi/linux/batman_adv.h | 12 +++
net/batman-adv/bridge_loop_avoidance.c | 169 +++++++++++++++++++++++++++++++++
net/batman-adv/bridge_loop_avoidance.h | 10 +-
net/batman-adv/netlink.c | 12 +++
4 files changed, 202 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h
index 20b4dc4..778e238 100644
--- a/include/uapi/linux/batman_adv.h
+++ b/include/uapi/linux/batman_adv.h
@@ -91,6 +91,11 @@ enum batadv_tt_client_flags {
* @BATADV_ATTR_BANDWIDTH_UP: Reported uplink bandwidth
* @BATADV_ATTR_BANDWIDTH_DOWN: Reported downlink bandwidth
* @BATADV_ATTR_ROUTER: Gateway router MAC address
+ * @BATADV_ATTR_BLA_OWN: Flag indicating own originator
+ * @BATADV_ATTR_BLA_ADDRESS: Bridge loop avoidance claim MAC address
+ * @BATADV_ATTR_BLA_VID: BLA VLAN ID
+ * @BATADV_ATTR_BLA_BACKBONE: BLA gateway originator MAC address
+ * @BATADV_ATTR_BLA_CRC: BLA CRC
* @__BATADV_ATTR_AFTER_LAST: internal use
* @NUM_BATADV_ATTR: total number of batadv_nl_attrs available
* @BATADV_ATTR_MAX: highest attribute number currently defined
@@ -126,6 +131,11 @@ enum batadv_nl_attrs {
BATADV_ATTR_BANDWIDTH_UP,
BATADV_ATTR_BANDWIDTH_DOWN,
BATADV_ATTR_ROUTER,
+ BATADV_ATTR_BLA_OWN,
+ BATADV_ATTR_BLA_ADDRESS,
+ BATADV_ATTR_BLA_VID,
+ BATADV_ATTR_BLA_BACKBONE,
+ BATADV_ATTR_BLA_CRC,
/* add attributes above here, update the policy in netlink.c */
__BATADV_ATTR_AFTER_LAST,
NUM_BATADV_ATTR = __BATADV_ATTR_AFTER_LAST,
@@ -146,6 +156,7 @@ enum batadv_nl_attrs {
* @BATADV_CMD_GET_ORIGINATORS: Query list of originators
* @BATADV_CMD_GET_NEIGHBORS: Query list of neighbours
* @BATADV_CMD_GET_GATEWAYS: Query list of gateways
+ * @BATADV_CMD_GET_BLA_CLAIM: Query list of bridge loop avoidance claims
* @__BATADV_CMD_AFTER_LAST: internal use
* @BATADV_CMD_MAX: highest used command number
*/
@@ -161,6 +172,7 @@ enum batadv_nl_commands {
BATADV_CMD_GET_ORIGINATORS,
BATADV_CMD_GET_NEIGHBORS,
BATADV_CMD_GET_GATEWAYS,
+ BATADV_CMD_GET_BLA_CLAIM,
/* add new commands above here */
__BATADV_CMD_AFTER_LAST,
BATADV_CMD_MAX = __BATADV_CMD_AFTER_LAST - 1
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index e4f7494..122025e 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -35,6 +35,7 @@
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
+#include <linux/netlink.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
@@ -45,12 +46,18 @@
#include <linux/string.h>
#include <linux/workqueue.h>
#include <net/arp.h>
+#include <net/genetlink.h>
+#include <net/netlink.h>
+#include <net/sock.h>
+#include <uapi/linux/batman_adv.h>

#include "hard-interface.h"
#include "hash.h"
#include "log.h"
+#include "netlink.h"
#include "originator.h"
#include "packet.h"
+#include "soft-interface.h"
#include "sysfs.h"
#include "translation-table.h"

@@ -1984,6 +1991,168 @@ out:
}

/**
+ * batadv_bla_claim_dump_entry - dump one entry of the claim table
+ * to a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @seq: Sequence number of netlink message
+ * @primary_if: primary interface
+ * @claim: entry to dump
+ *
+ * Return: 0 or error code.
+ */
+static int
+batadv_bla_claim_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
+ struct batadv_hard_iface *primary_if,
+ struct batadv_bla_claim *claim)
+{
+ u8 *primary_addr = primary_if->net_dev->dev_addr;
+ u16 backbone_crc;
+ bool is_own;
+ void *hdr;
+ int ret = -EINVAL;
+
+ hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
+ NLM_F_MULTI, BATADV_CMD_GET_BLA_CLAIM);
+ if (!hdr) {
+ ret = -ENOBUFS;
+ goto out;
+ }
+
+ is_own = batadv_compare_eth(claim->backbone_gw->orig,
+ primary_addr);
+
+ spin_lock_bh(&claim->backbone_gw->crc_lock);
+ backbone_crc = claim->backbone_gw->crc;
+ spin_unlock_bh(&claim->backbone_gw->crc_lock);
+
+ if (is_own)
+ if (nla_put_flag(msg, BATADV_ATTR_BLA_OWN)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ if (nla_put(msg, BATADV_ATTR_BLA_ADDRESS, ETH_ALEN, claim->addr) ||
+ nla_put_u16(msg, BATADV_ATTR_BLA_VID, claim->vid) ||
+ nla_put(msg, BATADV_ATTR_BLA_BACKBONE, ETH_ALEN,
+ claim->backbone_gw->orig) ||
+ nla_put_u16(msg, BATADV_ATTR_BLA_CRC,
+ backbone_crc)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ genlmsg_end(msg, hdr);
+ ret = 0;
+
+out:
+ return ret;
+}
+
+/**
+ * batadv_bla_claim_dump_bucket - dump one bucket of the claim table
+ * to a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @seq: Sequence number of netlink message
+ * @primary_if: primary interface
+ * @head: bucket to dump
+ * @idx_skip: How many entries to skip
+ *
+ * Return: always 0.
+ */
+static int
+batadv_bla_claim_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
+ struct batadv_hard_iface *primary_if,
+ struct hlist_head *head, int *idx_skip)
+{
+ struct batadv_bla_claim *claim;
+ int idx = 0;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(claim, head, hash_entry) {
+ if (idx++ < *idx_skip)
+ continue;
+ if (batadv_bla_claim_dump_entry(msg, portid, seq,
+ primary_if, claim)) {
+ *idx_skip = idx - 1;
+ goto unlock;
+ }
+ }
+
+ *idx_skip = idx;
+unlock:
+ rcu_read_unlock();
+ return 0;
+}
+
+/**
+ * batadv_bla_claim_dump - dump claim table to a netlink socket
+ * @msg: buffer for the message
+ * @cb: callback structure containing arguments
+ *
+ * Return: message length.
+ */
+int batadv_bla_claim_dump(struct sk_buff *msg, struct netlink_callback *cb)
+{
+ struct batadv_hard_iface *primary_if = NULL;
+ int portid = NETLINK_CB(cb->skb).portid;
+ struct net *net = sock_net(cb->skb->sk);
+ struct net_device *soft_iface = NULL;
+ struct batadv_hashtable *hash;
+ struct batadv_priv *bat_priv;
+ int bucket = cb->args[0];
+ struct hlist_head *head;
+ int idx = cb->args[1];
+ int ifindex;
+ int ret = 0;
+
+ ifindex = batadv_netlink_get_ifindex(cb->nlh,
+ BATADV_ATTR_MESH_IFINDEX);
+ if (!ifindex)
+ return -EINVAL;
+
+ soft_iface = dev_get_by_index(net, ifindex);
+ if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ bat_priv = netdev_priv(soft_iface);
+ hash = bat_priv->bla.claim_hash;
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ while (bucket < hash->size) {
+ head = &hash->table[bucket];
+
+ if (batadv_bla_claim_dump_bucket(msg, portid,
+ cb->nlh->nlmsg_seq,
+ primary_if, head, &idx))
+ break;
+ bucket++;
+ }
+
+ cb->args[0] = bucket;
+ cb->args[1] = idx;
+
+ ret = msg->len;
+
+out:
+ if (primary_if)
+ batadv_hardif_put(primary_if);
+
+ if (soft_iface)
+ dev_put(soft_iface);
+
+ return ret;
+}
+
+/**
* batadv_bla_backbone_table_seq_print_text - print the backbone table in a seq
* file
* @seq: seq file to print on
diff --git a/net/batman-adv/bridge_loop_avoidance.h b/net/batman-adv/bridge_loop_avoidance.h
index 0f01dae..a80b9e9 100644
--- a/net/batman-adv/bridge_loop_avoidance.h
+++ b/net/batman-adv/bridge_loop_avoidance.h
@@ -23,6 +23,7 @@
#include <linux/types.h>

struct net_device;
+struct netlink_callback;
struct seq_file;
struct sk_buff;

@@ -35,6 +36,7 @@ bool batadv_bla_is_backbone_gw(struct sk_buff *skb,
struct batadv_orig_node *orig_node,
int hdr_size);
int batadv_bla_claim_table_seq_print_text(struct seq_file *seq, void *offset);
+int batadv_bla_claim_dump(struct sk_buff *msg, struct netlink_callback *cb);
int batadv_bla_backbone_table_seq_print_text(struct seq_file *seq,
void *offset);
bool batadv_bla_is_backbone_gw_orig(struct batadv_priv *bat_priv, u8 *orig,
@@ -47,7 +49,7 @@ void batadv_bla_update_orig_address(struct batadv_priv *bat_priv,
void batadv_bla_status_update(struct net_device *net_dev);
int batadv_bla_init(struct batadv_priv *bat_priv);
void batadv_bla_free(struct batadv_priv *bat_priv);
-
+int batadv_bla_claim_dump(struct sk_buff *msg, struct netlink_callback *cb);
#define BATADV_BLA_CRC_INIT 0
#else /* ifdef CONFIG_BATMAN_ADV_BLA */

@@ -112,6 +114,12 @@ static inline void batadv_bla_free(struct batadv_priv *bat_priv)
{
}

+static inline int batadv_bla_claim_dump(struct sk_buff *msg,
+ struct netlink_callback *cb)
+{
+ return -EOPNOTSUPP;
+}
+
#endif /* ifdef CONFIG_BATMAN_ADV_BLA */

#endif /* ifndef _NET_BATMAN_ADV_BLA_H_ */
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 7209fc1..93a4c5d 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -38,6 +38,7 @@
#include <uapi/linux/batman_adv.h>

#include "bat_algo.h"
+#include "bridge_loop_avoidance.h"
#include "gateway_client.h"
#include "hard-interface.h"
#include "originator.h"
@@ -91,6 +92,11 @@ static struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
[BATADV_ATTR_BANDWIDTH_UP] = { .type = NLA_U32 },
[BATADV_ATTR_BANDWIDTH_DOWN] = { .type = NLA_U32 },
[BATADV_ATTR_ROUTER] = { .len = ETH_ALEN },
+ [BATADV_ATTR_BLA_OWN] = { .type = NLA_FLAG },
+ [BATADV_ATTR_BLA_ADDRESS] = { .len = ETH_ALEN },
+ [BATADV_ATTR_BLA_VID] = { .type = NLA_U16 },
+ [BATADV_ATTR_BLA_BACKBONE] = { .len = ETH_ALEN },
+ [BATADV_ATTR_BLA_CRC] = { .type = NLA_U16 },
};

/**
@@ -580,6 +586,12 @@ static struct genl_ops batadv_netlink_ops[] = {
.policy = batadv_netlink_policy,
.dumpit = batadv_gw_dump,
},
+ {
+ .cmd = BATADV_CMD_GET_BLA_CLAIM,
+ .flags = GENL_ADMIN_PERM,
+ .policy = batadv_netlink_policy,
+ .dumpit = batadv_bla_claim_dump,
+ },
};

/**
--
2.8.1