1/* AFS network device helpers
2 *
3 * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
4 */
5
6#include <linux/string.h>
7#include <linux/rtnetlink.h>
8#include <linux/inetdevice.h>
9#include <linux/netdevice.h>
10#include <linux/if_arp.h>
11#include <net/net_namespace.h>
12#include "internal.h"
13
14/*
15 * get a MAC address from a random ethernet interface that has a real one
16 * - the buffer will normally be 6 bytes in size
17 */
18int afs_get_MAC_address(u8 *mac, size_t maclen)
19{
20	struct net_device *dev;
21	int ret = -ENODEV;
22
23	BUG_ON(maclen != ETH_ALEN);
24
25	rtnl_lock();
26	dev = __dev_getfirstbyhwtype(&init_net, ARPHRD_ETHER);
27	if (dev) {
28		memcpy(mac, dev->dev_addr, maclen);
29		ret = 0;
30	}
31	rtnl_unlock();
32	return ret;
33}
34
35/*
36 * get a list of this system's interface IPv4 addresses, netmasks and MTUs
37 * - maxbufs must be at least 1
38 * - returns the number of interface records in the buffer
39 */
40int afs_get_ipv4_interfaces(struct afs_interface *bufs, size_t maxbufs,
41			    bool wantloopback)
42{
43	struct net_device *dev;
44	struct in_device *idev;
45	int n = 0;
46
47	ASSERT(maxbufs > 0);
48
49	rtnl_lock();
50	for_each_netdev(&init_net, dev) {
51		if (dev->type == ARPHRD_LOOPBACK && !wantloopback)
52			continue;
53		idev = __in_dev_get_rtnl(dev);
54		if (!idev)
55			continue;
56		for_primary_ifa(idev) {
57			bufs[n].address.s_addr = ifa->ifa_address;
58			bufs[n].netmask.s_addr = ifa->ifa_mask;
59			bufs[n].mtu = dev->mtu;
60			n++;
61			if (n >= maxbufs)
62				goto out;
63		} endfor_ifa(idev);
64	}
65out:
66	rtnl_unlock();
67	return n;
68}
69