path: root/net/core/net-sysfs.c

/*
 * net-sysfs.c - network device class and attributes
 *
 * Copyright (c) 2003 Stephen Hemminger <shemminger@osdl.org>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/capability.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/slab.h>
#include <linux/nsproxy.h>
#include <net/sock.h>
#include <net/net_namespace.h>
#include <linux/rtnetlink.h>
#include <linux/wireless.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
#include <linux/jiffies.h>
#include <net/wext.h>

#include "net-sysfs.h"

#ifdef CONFIG_SYSFS
static const char fmt_hex[] = "%#x\n";
static const char fmt_long_hex[] = "%#lx\n";
static const char fmt_dec[] = "%d\n";
static const char fmt_udec[] = "%u\n";
static const char fmt_ulong[] = "%lu\n";
static const char fmt_u64[] = "%llu\n";

static inline int dev_isalive(const struct net_device *dev)
{
	return dev->reg_state <= NETREG_REGISTERED;
}

/* use same locking rules as GIF* ioctl's */
static ssize_t netdev_show(const struct device *dev,
			   struct device_attribute *attr, char *buf,
			   ssize_t (*format)(const struct net_device *, char *))
{
	struct net_device *net = to_net_dev(dev);
	ssize_t ret = -EINVAL;

	read_lock(&dev_base_lock);
	if (dev_isalive(net))
		ret = (*format)(net, buf);
	read_unlock(&dev_base_lock);

	return ret;
}

/* generate a show function for simple field */
#define NETDEVICE_SHOW(field, format_string)				\
static ssize_t format_##field(const struct net_device *net, char *buf)	\
{									\
	return sprintf(buf, format_string, net->field);			\
}									\
static ssize_t show_##field(struct device *dev,				\
			    struct device_attribute *attr, char *buf)	\
{									\
	return netdev_show(dev, attr, buf, format_##field);		\
}


/* use same locking and permission rules as SIF* ioctl's */
static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
			    const char *buf, size_t len,
			    int (*set)(struct net_device *, unsigned long))
{
	struct net_device *net = to_net_dev(dev);
	char *endp;
	unsigned long new;
	int ret = -EINVAL;

	if (!capable(CAP_NET_ADMIN))
		return -EPERM;

	new = simple_strtoul(buf, &endp, 0);
	if (endp == buf)
		goto err;

	if (!rtnl_trylock())
		return restart_syscall();

	if (dev_isalive(net)) {
		if ((ret = (*set)(net, new)) == 0)
			ret = len;
	}
	rtnl_unlock();
 err:
	return ret;
}

NETDEVICE_SHOW(dev_id, fmt_hex);
NETDEVICE_SHOW(addr_assign_type, fmt_dec);
NETDEVICE_SHOW(addr_len, fmt_dec);
NETDEVICE_SHOW(iflink, fmt_dec);
NETDEVICE_SHOW(ifindex, fmt_dec);
NETDEVICE_SHOW(type, fmt_dec);
NETDEVICE_SHOW(link_mode, fmt_dec);

/* use same locking rules as GIFHWADDR ioctl's */
static ssize_t show_address(struct device *dev, struct device_attribute *attr,
			    char *buf)
{
	struct net_device *net = to_net_dev(dev);
	ssize_t ret = -EINVAL;

	read_lock(&dev_base_lock);
	if (dev_isalive(net))
		ret = sysfs_format_mac(buf, net->dev_addr, net->addr_len);
	read_unlock(&dev_base_lock);
	return ret;
}

static ssize_t show_broadcast(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	struct net_device *net = to_net_dev(dev);
	if (dev_isalive(net))
		return sysfs_format_mac(buf, net->broadcast, net->addr_len);
	return -EINVAL;
}

static ssize_t show_carrier(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	struct net_device *netdev = to_net_dev(dev);
	if (netif_running(netdev)) {
		return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
	}
	return -EINVAL;
}

static ssize_t show_speed(struct device *dev,
			  struct device_attribute *attr, char *buf)
{
	struct net_device *netdev = to_net_dev(dev);
	int ret = -EINVAL;

	if (!rtnl_trylock())
		return restart_syscall();

	if (netif_running(netdev)) {
		struct ethtool_cmd cmd;
		if (!__ethtool_get_settings(netdev, &cmd))
			ret = sprintf(buf, fmt_udec, ethtool_cmd_speed(&cmd));
	}
	rtnl_unlock();
	return ret;
}

static ssize_t show_duplex(struct device *dev,
			   struct device_attribute *attr, char *buf)
{
	struct net_device *netdev = to_net_dev(dev);
	int ret = -EINVAL;

	if (!rtnl_trylock())
		return restart_syscall();

	if (netif_running(netdev)) {
		struct ethtool_cmd cmd;
		if (!__ethtool_get_settings(netdev, &cmd))
			ret = sprintf(buf, "%s\n",
				      cmd.duplex ? "full" : "half");
	}
	rtnl_unlock();
	return ret;
}

static ssize_t show_dormant(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	struct net_device *netdev = to_net_dev(dev);

	if (netif_running(netdev))
		return sprintf(buf, fmt_dec, !!netif_dormant(netdev));

	return -EINVAL;
}

static const char *const operstates[] = {
	"unknown",
	"notpresent", /* currently unused */
	"down",
	"lowerlayerdown",
	"testing", /* currently unused */
	"dormant",
	"up"
};

static ssize_t show_operstate(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	const struct net_device *netdev = to_net_dev(dev);
	unsigned char operstate;

	read_lock(&dev_base_lock);
	operstate = netdev->operstate;
	if (!netif_running(netdev))
		operstate = IF_OPER_DOWN;
	read_unlock(&dev_base_lock);

	if (operstate >= ARRAY_SIZE(operstates))
		return -EINVAL; /* should not happen */

	return sprintf(buf, "%s\n", operstates[operstate]);
}

/* read-write attributes */
NETDEVICE_SHOW(mtu, fmt_dec);

static int change_mtu(struct net_device *net, unsigned long new_mtu)
{
	return dev_set_mtu(net, (int) new_mtu);
}

static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
			 const char *buf, size_t len)
{
	return netdev_store(dev, attr, buf, len, change_mtu);
}

NETDEVICE_SHOW(flags, fmt_hex);

static int change_flags(struct net_device *net, unsigned long new_flags)
{
	return dev_change_flags(net, (unsigned) new_flags);
}

static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t len)
{
	return netdev_store(dev, attr, buf, len, change_flags);
}

NETDEVICE_SHOW(tx_queue_len, fmt_ulong);

static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
{
	net->tx_queue_len = new_len;
	return 0;
}

static ssize_t store_tx_queue_len(struct device *dev,
				  struct device_attribute *attr,
				  const char *buf, size_t len)
{
	return netdev_store(dev, attr, buf, len, change_tx_queue_len);
}

static ssize_t store_ifalias(struct device *dev, struct device_attribute *attr,
			     const char *buf, size_t len)
{
	struct net_device *netdev = to_net_dev(dev);
	size_t count = len;
	ssize_t ret;

	if (!capable(CAP_NET_ADMIN))
		return -EPERM;

	/* ignore trailing newline */
	if (len >  0 && buf[len - 1] == '\n')
		--count;

	if (!rtnl_trylock())
		return restart_syscall();
	ret = dev_set_alias(netdev, buf, count);
	rtnl_unlock();

	return ret < 0 ? ret : len;
}

static ssize_t show_ifalias(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	const struct net_device *netdev = to_net_dev(dev);
	ssize_t ret = 0;

	if (!rtnl_trylock())
		return restart_syscall();
	if (netdev->ifalias)
		ret = sprintf(buf, "%s\n", netdev->ifalias);
	rtnl_unlock();
	return ret;
}

NETDEVICE_SHOW(group, fmt_dec);

static int change_group(struct net_device *net, unsigned long new_group)
{
	dev_set_group(net, (int) new_group);
	return 0;
}

static ssize_t store_group(struct device *dev, struct device_attribute *attr,
			 const char *buf, size_t len)
{
	return netdev_store(dev, attr, buf, len, change_group);
}

static struct device_attribute net_class_attributes[] = {
	__ATTR(addr_assign_type, S_IRUGO, show_addr_assign_type, NULL),
	__ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
	__ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
	__ATTR(ifalias, S_IRUGO | S_IWUSR, show_ifalias, store_ifalias),
	__ATTR(iflink, S_IRUGO, show_iflink, NULL),
	__ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
	__ATTR(type, S_IRUGO, show_type, NULL),
	__ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
	__ATTR(address, S_IRUGO, show_address, NULL),
	__ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
	__ATTR(carrier, S_IRUGO, show_carrier, NULL),
	__ATTR(speed, S_IRUGO, show_speed, NULL),
	__ATTR(duplex, S_IRUGO, show_duplex, NULL),
	__ATTR(dormant, S_IRUGO, show_dormant, NULL),
	__ATTR(