[B.A.T.M.A.N.] [PATCH v10 03/16] batman-adv: netlink: add routing_algo query

Sven Eckelmann
2016-07-03T11:31:35Z

From: Matthias Schiffer <mschiffer@universe-factory.net>

BATADV_CMD_GET_ROUTING_ALGOS is used to get the list of supported routing
algorithms.

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_ROUTING_ALGOS, fix includes]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
compat-include/linux/netlink.h | 18 +++++++++++
include/uapi/linux/batman_adv.h | 2 ++
net/batman-adv/bat_algo.c | 68 +++++++++++++++++++++++++++++++++++++++++
net/batman-adv/bat_algo.h | 3 ++
net/batman-adv/netlink.c | 9 +++++-
net/batman-adv/netlink.h | 3 ++
6 files changed, 102 insertions(+), 1 deletion(-)

diff --git a/compat-include/linux/netlink.h b/compat-include/linux/netlink.h
index eb5b7f4..4f2185d 100644
--- a/compat-include/linux/netlink.h
+++ b/compat-include/linux/netlink.h
@@ -24,6 +24,24 @@
#include <linux/version.h>
#include_next <linux/netlink.h>

+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 7, 0)
+
+#include <net/scm.h>
+
+struct batadv_netlink_skb_parms {
+ struct ucred creds; /* Skb credentials */
+ union {
+ __u32 portid;
+ __u32 pid;
+ };
+ __u32 dst_group;
+};
+
+#undef NETLINK_CB
+#define NETLINK_CB(skb) (*(struct batadv_netlink_skb_parms *)&((skb)->cb))
+
+#endif /* < KERNEL_VERSION(3, 7, 0) */
+
#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 7, 0)

#include_next <net/netlink.h>
diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h
index acb72f8..297a04d 100644
--- a/include/uapi/linux/batman_adv.h
+++ b/include/uapi/linux/batman_adv.h
@@ -73,6 +73,7 @@ enum batadv_nl_attrs {
* @BATADV_CMD_GET_MESH_INFO: Query basic information about batman-adv device
* @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_AFTER_LAST: internal use
* @BATADV_CMD_MAX: highest used command number
*/
@@ -81,6 +82,7 @@ enum batadv_nl_commands {
BATADV_CMD_GET_MESH_INFO,
BATADV_CMD_TP_METER,
BATADV_CMD_TP_METER_CANCEL,
+ BATADV_CMD_GET_ROUTING_ALGOS,
/* add new commands above here */
__BATADV_CMD_AFTER_LAST,
BATADV_CMD_MAX = __BATADV_CMD_AFTER_LAST - 1
diff --git a/net/batman-adv/bat_algo.c b/net/batman-adv/bat_algo.c
index 81dbbf5..f2cc50d 100644
--- a/net/batman-adv/bat_algo.c
+++ b/net/batman-adv/bat_algo.c
@@ -20,12 +20,18 @@
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/moduleparam.h>
+#include <linux/netlink.h>
#include <linux/printk.h>
#include <linux/seq_file.h>
+#include <linux/skbuff.h>
#include <linux/stddef.h>
#include <linux/string.h>
+#include <net/genetlink.h>
+#include <net/netlink.h>
+#include <uapi/linux/batman_adv.h>

#include "bat_algo.h"
+#include "netlink.h"

char batadv_routing_algo[20] = "BATMAN_IV";
static struct hlist_head batadv_algo_list;
@@ -138,3 +144,65 @@ static struct kparam_string batadv_param_string_ra = {

module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra,
0644);
+
+/**
+ * batadv_algo_dump_entry - fill in information about one supported routing
+ * algorithm
+ * @msg: netlink message to be sent back
+ * @portid: Port to reply to
+ * @seq: Sequence number of message
+ * @bat_algo_ops: Algorithm to be dumped
+ *
+ * Return: Error number, or 0 on success
+ */
+static int batadv_algo_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
+ struct batadv_algo_ops *bat_algo_ops)
+{
+ void *hdr;
+
+ hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
+ NLM_F_MULTI, BATADV_CMD_GET_ROUTING_ALGOS);
+ if (!hdr)
+ return -EMSGSIZE;
+
+ if (nla_put_string(msg, BATADV_ATTR_ALGO_NAME, bat_algo_ops->name))
+ goto nla_put_failure;
+
+ genlmsg_end(msg, hdr);
+ return 0;
+
+ nla_put_failure:
+ genlmsg_cancel(msg, hdr);
+ return -EMSGSIZE;
+}
+
+/**
+ * batadv_algo_dump - fill in information about supported routing
+ * algorithms
+ * @msg: netlink message to be sent back
+ * @cb: Parameters to the netlink request
+ *
+ * Return: Length of reply message.
+ */
+int batadv_algo_dump(struct sk_buff *msg, struct netlink_callback *cb)
+{
+ int portid = NETLINK_CB(cb->skb).portid;
+ struct batadv_algo_ops *bat_algo_ops;
+ int skip = cb->args[0];
+ int i = 0;
+
+ hlist_for_each_entry(bat_algo_ops, &batadv_algo_list, list) {
+ if (i++ < skip)
+ continue;
+
+ if (batadv_algo_dump_entry(msg, portid, cb->nlh->nlmsg_seq,
+ bat_algo_ops)) {
+ i--;
+ break;
+ }
+ }
+
+ cb->args[0] = i;
+
+ return msg->len;
+}
diff --git a/net/batman-adv/bat_algo.h b/net/batman-adv/bat_algo.h
index 860d773..3b5b69c 100644
--- a/net/batman-adv/bat_algo.h
+++ b/net/batman-adv/bat_algo.h
@@ -22,7 +22,9 @@

#include <linux/types.h>

+struct netlink_callback;
struct seq_file;
+struct sk_buff;

extern char batadv_routing_algo[];
extern struct list_head batadv_hardif_list;
@@ -31,5 +33,6 @@ void batadv_algo_init(void);
int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops);
int batadv_algo_select(struct batadv_priv *bat_priv, char *name);
int batadv_algo_seq_print_text(struct seq_file *seq, void *offset);
+int batadv_algo_dump(struct sk_buff *msg, struct netlink_callback *cb);

#endif /* _NET_BATMAN_ADV_BAT_ALGO_H_ */
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 231f8ea..19fb265 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -32,13 +32,14 @@
#include <net/netlink.h>
#include <uapi/linux/batman_adv.h>

+#include "bat_algo.h"
#include "hard-interface.h"
#include "soft-interface.h"
#include "tp_meter.h"

struct sk_buff;

-static struct genl_family batadv_netlink_family = {
+struct genl_family batadv_netlink_family = {
.id = GENL_ID_GENERATE,
.hdrsize = 0,
.name = BATADV_NL_NAME,
@@ -399,6 +400,12 @@ static struct genl_ops batadv_netlink_ops[] = {
.policy = batadv_netlink_policy,
.doit = batadv_netlink_tp_meter_cancel,
},
+ {
+ .cmd = BATADV_CMD_GET_ROUTING_ALGOS,
+ .flags = GENL_ADMIN_PERM,
+ .policy = batadv_netlink_policy,
+ .dumpit = batadv_algo_dump,
+ },
};

/**
diff --git a/net/batman-adv/netlink.h b/net/batman-adv/netlink.h
index 945653a..b399f49 100644
--- a/net/batman-adv/netlink.h
+++ b/net/batman-adv/netlink.h
@@ -21,6 +21,7 @@
#include "main.h"

#include <linux/types.h>
+#include <net/genetlink.h>

void batadv_netlink_register(void);
void batadv_netlink_unregister(void);
@@ -29,4 +30,6 @@ int batadv_netlink_tpmeter_notify(struct batadv_priv *bat_priv, const u8 *dst,
u8 result, u32 test_time, u64 total_bytes,
u32 cookie);

+extern struct genl_family batadv_netlink_family;
+
#endif /* _NET_BATMAN_ADV_NETLINK_H_ */
--
2.8.1