[B.A.T.M.A.N.] [PATCH v8 10/14] batman-adv: add B.A.T.M.A.N. Dump gateways via netlink

Simon Wunderlich
2016-05-23T15:59:41Z

From: Andrew Lunn <andrew@lunn.ch>

Dump the list of gateways via the netlink socket.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[sven.eckelmann@open-mesh.com: add policy for attributes]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
include/uapi/linux/batman_adv.h | 8 +++
net/batman-adv/gateway_client.c | 148 ++++++++++++++++++++++++++++++++++++++++
net/batman-adv/gateway_client.h | 2 +
net/batman-adv/netlink.c | 10 +++
4 files changed, 168 insertions(+)

diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h
index 0cb6586..20b4dc4 100644
--- a/include/uapi/linux/batman_adv.h
+++ b/include/uapi/linux/batman_adv.h
@@ -88,6 +88,9 @@ enum batadv_tt_client_flags {
* @BATADV_ATTR_NEIGH_ADDRESS: Neighbour MAC address
* @BATADV_ATTR_TQ: TQ to neighbour
* @BATADV_ATTR_THROUGHPUT: Estimated throughput to Neighbour
+ * @BATADV_ATTR_BANDWIDTH_UP: Reported uplink bandwidth
+ * @BATADV_ATTR_BANDWIDTH_DOWN: Reported downlink bandwidth
+ * @BATADV_ATTR_ROUTER: Gateway router MAC address
* @__BATADV_ATTR_AFTER_LAST: internal use
* @NUM_BATADV_ATTR: total number of batadv_nl_attrs available
* @BATADV_ATTR_MAX: highest attribute number currently defined
@@ -120,6 +123,9 @@ enum batadv_nl_attrs {
BATADV_ATTR_NEIGH_ADDRESS,
BATADV_ATTR_TQ,
BATADV_ATTR_THROUGHPUT,
+ BATADV_ATTR_BANDWIDTH_UP,
+ BATADV_ATTR_BANDWIDTH_DOWN,
+ BATADV_ATTR_ROUTER,
/* add attributes above here, update the policy in netlink.c */
__BATADV_ATTR_AFTER_LAST,
NUM_BATADV_ATTR = __BATADV_ATTR_AFTER_LAST,
@@ -139,6 +145,7 @@ enum batadv_nl_attrs {
* @BATADV_CMD_GET_TRANSTABLE_GLOBAL Query list of global translations
* @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_AFTER_LAST: internal use
* @BATADV_CMD_MAX: highest used command number
*/
@@ -153,6 +160,7 @@ enum batadv_nl_commands {
BATADV_CMD_GET_TRANSTABLE_GLOBAL,
BATADV_CMD_GET_ORIGINATORS,
BATADV_CMD_GET_NEIGHBORS,
+ BATADV_CMD_GET_GATEWAYS,
/* add new commands above here */
__BATADV_CMD_AFTER_LAST,
BATADV_CMD_MAX = __BATADV_CMD_AFTER_LAST - 1
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index e108d45..85c67b5 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -20,6 +20,7 @@

#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>
@@ -31,6 +32,7 @@
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/netdevice.h>
+#include <linux/netlink.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
@@ -39,13 +41,19 @@
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/udp.h>
+#include <net/genetlink.h>
+#include <net/netlink.h>
+#include <net/sock.h>
+#include <uapi/linux/batman_adv.h>

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

@@ -664,6 +672,146 @@ out:
}

/**
+ * batadv_gw_dump_entry - Dump a gateway into a message
+ * @msg: Netlink message to dump into
+ * @portid: Port making netlink request
+ * @seq: Sequence number of netlink message
+ * @bat_priv: The bat priv with all the soft interface information
+ * @gw_node: Gateway to be dumped
+ *
+ * Return: Error code, or 0 on success
+ */
+static int
+batadv_gw_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
+ struct batadv_priv *bat_priv,
+ struct batadv_gw_node *gw_node)
+{
+ struct batadv_neigh_ifinfo *router_ifinfo = NULL;
+ struct batadv_neigh_node *router;
+ struct batadv_gw_node *curr_gw;
+ int ret = -EINVAL;
+ void *hdr;
+
+ router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
+ if (!router)
+ goto out;
+
+ router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
+ if (!router_ifinfo)
+ goto out;
+
+ curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
+
+ hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
+ NLM_F_MULTI, BATADV_CMD_GET_GATEWAYS);
+ if (!hdr) {
+ ret = -ENOBUFS;
+ goto out;
+ }
+
+ ret = -EMSGSIZE;
+
+ if (curr_gw == gw_node)
+ if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
+ gw_node->orig_node->orig) ||
+ nla_put_u8(msg, BATADV_ATTR_TQ, router_ifinfo->bat_iv.tq_avg) ||
+ nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN,
+ router->addr) ||
+ nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
+ router->if_incoming->net_dev->name) ||
+ nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
+ gw_node->bandwidth_down) ||
+ nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP,
+ gw_node->bandwidth_up)) {
+ genlmsg_cancel(msg, hdr);
+ goto out;
+ }
+
+ genlmsg_end(msg, hdr);
+ ret = 0;
+
+out:
+ if (router_ifinfo)
+ batadv_neigh_ifinfo_put(router_ifinfo);
+ if (router)
+ batadv_neigh_node_put(router);
+ return ret;
+}
+
+/**
+ * batadv_gw_dump - Dump gateways into a message
+ * @msg: Netlink message to dump into
+ * @cb: Control block containing additional options
+ *
+ * Return: Error code, or length of message
+ */
+int batadv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb)
+{
+ struct batadv_hard_iface *primary_if = NULL;
+ struct net *net = sock_net(cb->skb->sk);
+ int portid = NETLINK_CB(cb->skb).portid;
+ struct net_device *soft_iface = NULL;
+ struct batadv_gw_node *gw_node;
+ struct batadv_priv *bat_priv;
+ int idx_skip = cb->args[0];
+ int ifindex;
+ int idx = 0;
+ int ret;
+
+ 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);
+
+ primary_if = batadv_primary_if_get_selected(bat_priv);
+ if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
+ if (idx++ < idx_skip)
+ continue;
+
+ if (batadv_gw_dump_entry(msg, portid, cb->nlh->nlmsg_seq,
+ bat_priv, gw_node)) {
+ idx_skip = idx - 1;
+ ret = msg->len;
+ goto unlock;
+ }
+ }
+
+ idx_skip = idx;
+ ret = msg->len;
+unlock:
+ rcu_read_unlock();
+
+out:
+ if (primary_if)
+ batadv_hardif_put(primary_if);
+ if (soft_iface)
+ dev_put(soft_iface);
+
+ cb->args[0] = idx_skip;
+
+ return ret;
+}
+
+/**
* batadv_gw_dhcp_recipient_get - check if a packet is a DHCP message
* @skb: the packet to check
* @header_len: a pointer to the batman-adv header size
diff --git a/net/batman-adv/gateway_client.h b/net/batman-adv/gateway_client.h
index 582dd8c..f1b2d39 100644
--- a/net/batman-adv/gateway_client.h
+++ b/net/batman-adv/gateway_client.h
@@ -23,6 +23,7 @@
#include <linux/types.h>

struct batadv_tvlv_gateway_data;
+struct netlink_callback;
struct seq_file;
struct sk_buff;

@@ -40,6 +41,7 @@ void batadv_gw_node_delete(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig_node);
void batadv_gw_node_free(struct batadv_priv *bat_priv);
int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset);
+int batadv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb);
bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, struct sk_buff *skb);
enum batadv_dhcp_recipient
batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 26ca596..7209fc1 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 "gateway_client.h"
#include "hard-interface.h"
#include "originator.h"
#include "soft-interface.h"
@@ -87,6 +88,9 @@ static struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
[BATADV_ATTR_NEIGH_ADDRESS] = { .len = ETH_ALEN },
[BATADV_ATTR_TQ] = { .type = NLA_U8 },
[BATADV_ATTR_THROUGHPUT] = { .type = NLA_U32 },
+ [BATADV_ATTR_BANDWIDTH_UP] = { .type = NLA_U32 },
+ [BATADV_ATTR_BANDWIDTH_DOWN] = { .type = NLA_U32 },
+ [BATADV_ATTR_ROUTER] = { .len = ETH_ALEN },
};

/**
@@ -570,6 +574,12 @@ static struct genl_ops batadv_netlink_ops[] = {
.policy = batadv_netlink_policy,
.dumpit = batadv_hardif_neigh_dump,
},
+ {
+ .cmd = BATADV_CMD_GET_GATEWAYS,
+ .flags = GENL_ADMIN_PERM,
+ .policy = batadv_netlink_policy,
+ .dumpit = batadv_gw_dump,
+ },
};

/**
--
2.8.1