root/fs/afs/netdevices.c

DEFINITIONS

1. afs_get_MAC_address
2. afs_get_ipv4_interfaces

/* AFS network device helpers
 *
 * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
 */

#include <linux/string.h>
#include <linux/rtnetlink.h>
#include <linux/inetdevice.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <net/net_namespace.h>
#include "internal.h"

/*
 * get a MAC address from a random ethernet interface that has a real one
 * - the buffer will normally be 6 bytes in size
 */
int afs_get_MAC_address(u8 *mac, size_t maclen)
{
        struct net_device *dev;
        int ret = -ENODEV;

        if (maclen != ETH_ALEN)
                BUG();

        rtnl_lock();
        dev = __dev_getfirstbyhwtype(&init_net, ARPHRD_ETHER);
        if (dev) {
                memcpy(mac, dev->dev_addr, maclen);
                ret = 0;
        }
        rtnl_unlock();
        return ret;
}

/*
 * get a list of this system's interface IPv4 addresses, netmasks and MTUs
 * - maxbufs must be at least 1
 * - returns the number of interface records in the buffer
 */
int afs_get_ipv4_interfaces(struct afs_interface *bufs, size_t maxbufs,
                            bool wantloopback)
{
        struct net_device *dev;
        struct in_device *idev;
        int n = 0;

        ASSERT(maxbufs > 0);

        rtnl_lock();
        for_each_netdev(&init_net, dev) {
                if (dev->type == ARPHRD_LOOPBACK && !wantloopback)
                        continue;
                idev = __in_dev_get_rtnl(dev);
                if (!idev)
                        continue;
                for_primary_ifa(idev) {
                        bufs[n].address.s_addr = ifa->ifa_address;
                        bufs[n].netmask.s_addr = ifa->ifa_mask;
                        bufs[n].mtu = dev->mtu;
                        n++;
                        if (n >= maxbufs)
                                goto out;
                } endfor_ifa(idev);
        }
out:
        rtnl_unlock();
        return n;
}