batman-adv: netlink: hardif query

BATADV_CMD_GET_HARDIFS will return the list of hardifs (including index,
name and MAC address) of all hardifs for a given softif.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[sven.eckelmann@open-mesh.com: Reduce the number of changes to
BATADV_CMD_GET_HARDIFS, add policy for attributes]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>

diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h
index 7afce444a64ed3bc9768805f3fc09cf08eb26ff2..8abcbca14b6a32002f3cbeb50d802844f570ebc7 100644 (file)
--- a/include/uapi/linux/batman_adv.h
+++ b/include/uapi/linux/batman_adv.h
@@ -40,6 +40,7 @@
  * @BATADV_ATTR_TPMETER_BYTES: amount of acked bytes during run
  * @BATADV_ATTR_TPMETER_COOKIE: session cookie to match tp_meter session
  * @BATADV_ATTR_PAD: attribute used for padding for 64-bit alignment
+ * @BATADV_ATTR_ACTIVE: Flag indicating if the hard interface is active
  * @__BATADV_ATTR_AFTER_LAST: internal use
  * @NUM_BATADV_ATTR: total number of batadv_nl_attrs available
  * @BATADV_ATTR_MAX: highest attribute number currently defined
@@ -60,6 +61,7 @@ enum batadv_nl_attrs {
        BATADV_ATTR_TPMETER_BYTES,
        BATADV_ATTR_TPMETER_COOKIE,
        BATADV_ATTR_PAD,
+       BATADV_ATTR_ACTIVE,
        /* add attributes above here, update the policy in netlink.c */
        __BATADV_ATTR_AFTER_LAST,
        NUM_BATADV_ATTR = __BATADV_ATTR_AFTER_LAST,
@@ -74,6 +76,7 @@ enum batadv_nl_attrs {
  * @BATADV_CMD_TP_METER: Start a tp meter session
  * @BATADV_CMD_TP_METER_CANCEL: Cancel a tp meter session
  * @BATADV_CMD_GET_ROUTING_ALGOS: Query the list of routing algorithms.
+ * @BATADV_CMD_GET_HARDIFS: Query list of hard interfaces
  * @__BATADV_CMD_AFTER_LAST: internal use
  * @BATADV_CMD_MAX: highest used command number
  */
@@ -83,6 +86,7 @@ enum batadv_nl_commands {
        BATADV_CMD_TP_METER,
        BATADV_CMD_TP_METER_CANCEL,
        BATADV_CMD_GET_ROUTING_ALGOS,
+       BATADV_CMD_GET_HARDIFS,
        /* add new commands above here */
        __BATADV_CMD_AFTER_LAST,
        BATADV_CMD_MAX = __BATADV_CMD_AFTER_LAST - 1

diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 19fb2657e274e2372be5a95021e11bdf05f62c9c..3f872d6eec5791ad7296d2d178675cf4ce099ee5 100644 (file)
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -26,10 +26,14 @@
 #include <linux/netdevice.h>
 #include <linux/netlink.h>
 #include <linux/printk.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/skbuff.h>
 #include <linux/stddef.h>
 #include <linux/types.h>
 #include <net/genetlink.h>
 #include <net/netlink.h>
+#include <net/sock.h>
 #include <uapi/linux/batman_adv.h>
 
 #include "bat_algo.h"
@@ -37,8 +41,6 @@
 #include "soft-interface.h"
 #include "tp_meter.h"
 
-struct sk_buff;
-
 struct genl_family batadv_netlink_family = {
        .id = GENL_ID_GENERATE,
        .hdrsize = 0,
@@ -70,8 +72,24 @@ static struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
        [BATADV_ATTR_TPMETER_TEST_TIME] = { .type = NLA_U32 },
        [BATADV_ATTR_TPMETER_BYTES]     = { .type = NLA_U64 },
        [BATADV_ATTR_TPMETER_COOKIE]    = { .type = NLA_U32 },
+       [BATADV_ATTR_ACTIVE]            = { .type = NLA_FLAG },
 };
 
+/**
+ * batadv_netlink_get_ifindex - Extract an interface index from a message
+ * @nlh: Message header
+ * @attrtype: Attribute which holds an interface index
+ *
+ * Return: interface index, or 0.
+ */
+static int
+batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype)
+{
+       struct nlattr *attr = nlmsg_find_attr(nlh, GENL_HDRLEN, attrtype);
+
+       return attr ? nla_get_u32(attr) : 0;
+}
+
 /**
  * batadv_netlink_mesh_info_put - fill in generic information about mesh
  *  interface
@@ -381,6 +399,106 @@ out:
        return ret;
 }
 
+/**
+ * batadv_netlink_dump_hardif_entry - Dump one hard interface into a message
+ * @msg: Netlink message to dump into
+ * @portid: Port making netlink request
+ * @seq: Sequence number of netlink message
+ * @hard_iface: Hard interface to dump
+ *
+ * Return: error code, or 0 on success
+ */
+static int
+batadv_netlink_dump_hardif_entry(struct sk_buff *msg, u32 portid, u32 seq,
+                                struct batadv_hard_iface *hard_iface)
+{
+       struct net_device *net_dev = hard_iface->net_dev;
+       void *hdr;
+
+       hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
+                         BATADV_CMD_GET_HARDIFS);
+       if (!hdr)
+               return -EMSGSIZE;
+
+       if (nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
+                       net_dev->ifindex) ||
+           nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
+                          net_dev->name) ||
+           nla_put(msg, BATADV_ATTR_HARD_ADDRESS, ETH_ALEN,
+                   net_dev->dev_addr))
+               goto nla_put_failure;
+
+       if (hard_iface->if_status == BATADV_IF_ACTIVE) {
+               if (nla_put_flag(msg, BATADV_ATTR_ACTIVE))
+                       goto nla_put_failure;
+       }
+
+       genlmsg_end(msg, hdr);
+       return 0;
+
+ nla_put_failure:
+       genlmsg_cancel(msg, hdr);
+       return -EMSGSIZE;
+}
+
+/**
+ * batadv_netlink_dump_hardifs - Dump all hard interface into a messages
+ * @msg: Netlink message to dump into
+ * @cb: Parameters from query
+ *
+ * Return: error code, or length of reply message on success
+ */
+static int
+batadv_netlink_dump_hardifs(struct sk_buff *msg, struct netlink_callback *cb)
+{
+       struct net *net = sock_net(cb->skb->sk);
+       struct net_device *soft_iface;
+       struct batadv_hard_iface *hard_iface;
+       int ifindex;
+       int portid = NETLINK_CB(cb->skb).portid;
+       int seq = cb->nlh->nlmsg_seq;
+       int skip = cb->args[0];
+       int i = 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)
+               return -ENODEV;
+
+       if (!batadv_softif_is_valid(soft_iface)) {
+               dev_put(soft_iface);
+               return -ENODEV;
+       }
+
+       rcu_read_lock();
+
+       list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+               if (hard_iface->soft_iface != soft_iface)
+                       continue;
+
+               if (i++ < skip)
+                       continue;
+
+               if (batadv_netlink_dump_hardif_entry(msg, portid, seq,
+                                                    hard_iface)) {
+                       i--;
+                       break;
+               }
+       }
+
+       rcu_read_unlock();
+
+       dev_put(soft_iface);
+
+       cb->args[0] = i;
+
+       return msg->len;
+}
+
 static struct genl_ops batadv_netlink_ops[] = {
        {
                .cmd = BATADV_CMD_GET_MESH_INFO,
@@ -406,6 +524,12 @@ static struct genl_ops batadv_netlink_ops[] = {
                .policy = batadv_netlink_policy,
                .dumpit = batadv_algo_dump,
        },
+       {
+               .cmd = BATADV_CMD_GET_HARDIFS,
+               .flags = GENL_ADMIN_PERM,
+               .policy = batadv_netlink_policy,
+               .dumpit = batadv_netlink_dump_hardifs,
+       },
 };
 
 /**