Commit 60040513 authored by Sven Eckelmann's avatar Sven Eckelmann Committed by Simon Wunderlich
Browse files

batman-adv: Prepare framework for mesh genl config 



The batman-adv configuration interface was implemented solely using sysfs.
This approach was condemned by non-batadv developers as "huge mistake".
Instead a netlink/genl based implementation was suggested.

The main objects for this configuration is the mesh/soft-interface object.
Its actual object in memory already contains most of the available
configuration settings. The genl interface reflects this by allowing to
get/set it using the mesh specific commands.

The BATADV_CMD_GET_MESH_INFO (or short version BATADV_CMD_GET_MESH) is
reused as get command because it already provides the content of other
information from the mesh/soft-interface which are not yet configuration
specific.

The set command BATADV_CMD_SET_MESH will also notify interested userspace
listeners of the "config" mcast group using the BATADV_CMD_SET_MESH command
message type that settings might have been changed and what the current
values are.

Signed-off-by: default avatarSven Eckelmann <sven@narfation.org>
Signed-off-by: default avatarSimon Wunderlich <sw@simonwunderlich.de>
parent c4a7a8d9

include/uapi/linux/batman_adv.h

+13 −3
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 


#define BATADV_NL_NAME "batadv"



#define BATADV_NL_MCAST_GROUP_CONFIG	"config"

#define BATADV_NL_MCAST_GROUP_TPMETER	"tpmeter"



/**
@@ -372,10 +373,14 @@ enum batadv_nl_commands { 
	BATADV_CMD_UNSPEC,



	/**

	 * @BATADV_CMD_GET_MESH_INFO: Query basic information about batman-adv

	 * device

	 * @BATADV_CMD_GET_MESH: Get attributes from softif/mesh

	 */

	BATADV_CMD_GET_MESH_INFO,

	BATADV_CMD_GET_MESH,



	/**

	 * @BATADV_CMD_GET_MESH_INFO: Alias for @BATADV_CMD_GET_MESH

	 */

	BATADV_CMD_GET_MESH_INFO = BATADV_CMD_GET_MESH,



	/**

	 * @BATADV_CMD_TP_METER: Start a tp meter session
@@ -443,6 +448,11 @@ enum batadv_nl_commands { 
	 */

	BATADV_CMD_GET_MCAST_FLAGS,



	/**

	 * @BATADV_CMD_SET_MESH: Set attributes for softif/mesh

	 */

	BATADV_CMD_SET_MESH,



	/* add new commands above here */



	/**

net/batman-adv/netlink.c

+98 −62
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ struct genl_family batadv_netlink_family; 


/* multicast groups */

enum batadv_netlink_multicast_groups {

	BATADV_NL_MCGRP_CONFIG,

	BATADV_NL_MCGRP_TPMETER,

};
@@ -78,6 +79,7 @@ enum batadv_genl_ops_flags { 
};



static const struct genl_multicast_group batadv_netlink_mcgrps[] = {

	[BATADV_NL_MCGRP_CONFIG] = { .name = BATADV_NL_MCAST_GROUP_CONFIG },

	[BATADV_NL_MCGRP_TPMETER] = { .name = BATADV_NL_MCAST_GROUP_TPMETER },

};
@@ -138,20 +140,29 @@ batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype) 
}



/**

 * batadv_netlink_mesh_info_put() - fill in generic information about mesh

 *  interface

 * @msg: netlink message to be sent back

 * @soft_iface: interface for which the data should be taken

 * batadv_netlink_mesh_fill() - Fill message with mesh attributes

 * @msg: Netlink message to dump into

 * @bat_priv: the bat priv with all the soft interface information

 * @cmd: type of message to generate

 * @portid: Port making netlink request

 * @seq: sequence number for message

 * @flags: Additional flags for message

 *

 * Return: 0 on success, < 0 on error

 * Return: 0 on success or negative error number in case of failure

 */

static int

batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface)

static int batadv_netlink_mesh_fill(struct sk_buff *msg,

				    struct batadv_priv *bat_priv,

				    enum batadv_nl_commands cmd,

				    u32 portid, u32 seq, int flags)

{

	struct batadv_priv *bat_priv = netdev_priv(soft_iface);

	struct net_device *soft_iface = bat_priv->soft_iface;

	struct batadv_hard_iface *primary_if = NULL;

	struct net_device *hard_iface;

	int ret = -ENOBUFS;

	void *hdr;



	hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, flags, cmd);

	if (!hdr)

		return -ENOBUFS;



	if (nla_put_string(msg, BATADV_ATTR_VERSION, BATADV_SOURCE_VERSION) ||

	    nla_put_string(msg, BATADV_ATTR_ALGO_NAME,
@@ -162,16 +173,16 @@ batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface) 
		    soft_iface->dev_addr) ||

	    nla_put_u8(msg, BATADV_ATTR_TT_TTVN,

		       (u8)atomic_read(&bat_priv->tt.vn)))

		goto out;

		goto nla_put_failure;



#ifdef CONFIG_BATMAN_ADV_BLA

	if (nla_put_u16(msg, BATADV_ATTR_BLA_CRC,

			ntohs(bat_priv->bla.claim_dest.group)))

		goto out;

		goto nla_put_failure;

#endif



	if (batadv_mcast_mesh_info_put(msg, bat_priv))

		goto out;

		goto nla_put_failure;



	primary_if = batadv_primary_if_get_selected(bat_priv);

	if (primary_if && primary_if->if_status == BATADV_IF_ACTIVE) {
@@ -183,77 +194,95 @@ batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface) 
				   hard_iface->name) ||

		    nla_put(msg, BATADV_ATTR_HARD_ADDRESS, ETH_ALEN,

			    hard_iface->dev_addr))

			goto out;

			goto nla_put_failure;

	}



	ret = 0;

	if (primary_if)

		batadv_hardif_put(primary_if);



 out:

	genlmsg_end(msg, hdr);

	return 0;



nla_put_failure:

	if (primary_if)

		batadv_hardif_put(primary_if);



	return ret;

	genlmsg_cancel(msg, hdr);

	return -EMSGSIZE;

}



/**

 * batadv_netlink_get_mesh_info() - handle incoming BATADV_CMD_GET_MESH_INFO

 *  netlink request

 * @skb: received netlink message

 * @info: receiver information

 * batadv_netlink_notify_mesh() - send softif attributes to listener

 * @bat_priv: the bat priv with all the soft interface information

 *

 * Return: 0 on success, < 0 on error

 */

static int

batadv_netlink_get_mesh_info(struct sk_buff *skb, struct genl_info *info)

static int batadv_netlink_notify_mesh(struct batadv_priv *bat_priv)

{

	struct net *net = genl_info_net(info);

	struct net_device *soft_iface;

	struct sk_buff *msg = NULL;

	void *msg_head;

	int ifindex;

	struct sk_buff *msg;

	int ret;



	if (!info->attrs[BATADV_ATTR_MESH_IFINDEX])

		return -EINVAL;



	ifindex = nla_get_u32(info->attrs[BATADV_ATTR_MESH_IFINDEX]);

	if (!ifindex)

		return -EINVAL;

	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);

	if (!msg)

		return -ENOMEM;



	soft_iface = dev_get_by_index(net, ifindex);

	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {

		ret = -ENODEV;

		goto out;

	ret = batadv_netlink_mesh_fill(msg, bat_priv, BATADV_CMD_SET_MESH,

				       0, 0, 0);

	if (ret < 0) {

		nlmsg_free(msg);

		return ret;

	}



	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);

	if (!msg) {

		ret = -ENOMEM;

		goto out;

	}

	genlmsg_multicast_netns(&batadv_netlink_family,

				dev_net(bat_priv->soft_iface), msg, 0,

				BATADV_NL_MCGRP_CONFIG, GFP_KERNEL);



	msg_head = genlmsg_put(msg, info->snd_portid, info->snd_seq,

			       &batadv_netlink_family, 0,

			       BATADV_CMD_GET_MESH_INFO);

	if (!msg_head) {

		ret = -ENOBUFS;

		goto out;

	return 0;

}



	ret = batadv_netlink_mesh_info_put(msg, soft_iface);

/**

 * batadv_netlink_get_mesh() - Get softif attributes

 * @skb: Netlink message with request data

 * @info: receiver information

 *

 * Return: 0 on success or negative error number in case of failure

 */

static int batadv_netlink_get_mesh(struct sk_buff *skb, struct genl_info *info)

{

	struct batadv_priv *bat_priv = info->user_ptr[0];

	struct sk_buff *msg;

	int ret;



 out:

	if (soft_iface)

		dev_put(soft_iface);

	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);

	if (!msg)

		return -ENOMEM;



	if (ret) {

		if (msg)

	ret = batadv_netlink_mesh_fill(msg, bat_priv, BATADV_CMD_GET_MESH,

				       info->snd_portid, info->snd_seq, 0);

	if (ret < 0) {

		nlmsg_free(msg);

		return ret;

	}



	genlmsg_end(msg, msg_head);

	return genlmsg_reply(msg, info);

	ret = genlmsg_reply(msg, info);



	return ret;

}



/**

 * batadv_netlink_set_mesh() - Set softif attributes

 * @skb: Netlink message with request data

 * @info: receiver information

 *

 * Return: 0 on success or negative error number in case of failure

 */

static int batadv_netlink_set_mesh(struct sk_buff *skb, struct genl_info *info)

{

	struct batadv_priv *bat_priv = info->user_ptr[0];



	batadv_netlink_notify_mesh(bat_priv);



	return 0;

}



/**
@@ -600,10 +629,11 @@ static void batadv_post_doit(const struct genl_ops *ops, struct sk_buff *skb, 


static const struct genl_ops batadv_netlink_ops[] = {

	{

		.cmd = BATADV_CMD_GET_MESH_INFO,

		.flags = GENL_ADMIN_PERM,

		.cmd = BATADV_CMD_GET_MESH,

		/* can be retrieved by unprivileged users */

		.policy = batadv_netlink_policy,

		.doit = batadv_netlink_get_mesh_info,

		.doit = batadv_netlink_get_mesh,

		.internal_flags = BATADV_FLAG_NEED_MESH,

	},

	{

		.cmd = BATADV_CMD_TP_METER,
@@ -685,7 +715,13 @@ static const struct genl_ops batadv_netlink_ops[] = { 
		.policy = batadv_netlink_policy,

		.dumpit = batadv_mcast_flags_dump,

	},



	{

		.cmd = BATADV_CMD_SET_MESH,

		.flags = GENL_ADMIN_PERM,

		.policy = batadv_netlink_policy,

		.doit = batadv_netlink_set_mesh,

		.internal_flags = BATADV_FLAG_NEED_MESH,

	},

};



struct genl_family batadv_netlink_family __ro_after_init = {

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