1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *
4 * Authors:
5 * (C) 2015 Pengutronix, Alexander Aring <aar@pengutronix.de>
6 */
7
8#include <linux/if_arp.h>
9#include <linux/module.h>
10
11#include <net/6lowpan.h>
12#include <net/addrconf.h>
13
14#include "6lowpan_i.h"
15
16int lowpan_register_netdevice(struct net_device *dev,
17 enum lowpan_lltypes lltype)
18{
19 int i, ret;
20
21 switch (lltype) {
22 case LOWPAN_LLTYPE_IEEE802154:
23 dev->addr_len = EUI64_ADDR_LEN;
24 break;
25
26 case LOWPAN_LLTYPE_BTLE:
27 dev->addr_len = ETH_ALEN;
28 break;
29 }
30
31 dev->type = ARPHRD_6LOWPAN;
32 dev->mtu = IPV6_MIN_MTU;
33
34 lowpan_dev(dev)->lltype = lltype;
35
36 spin_lock_init(&lowpan_dev(dev)->ctx.lock);
37 for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++)
38 lowpan_dev(dev)->ctx.table[i].id = i;
39
40 dev->ndisc_ops = &lowpan_ndisc_ops;
41
42 ret = register_netdevice(dev);
43 if (ret < 0)
44 return ret;
45
46 lowpan_dev_debugfs_init(dev);
47
48 return ret;
49}
50EXPORT_SYMBOL(lowpan_register_netdevice);
51
52int lowpan_register_netdev(struct net_device *dev,
53 enum lowpan_lltypes lltype)
54{
55 int ret;
56
57 rtnl_lock();
58 ret = lowpan_register_netdevice(dev, lltype);
59 rtnl_unlock();
60 return ret;
61}
62EXPORT_SYMBOL(lowpan_register_netdev);
63
64void lowpan_unregister_netdevice(struct net_device *dev)
65{
66 unregister_netdevice(dev);
67 lowpan_dev_debugfs_exit(dev);
68}
69EXPORT_SYMBOL(lowpan_unregister_netdevice);
70
71void lowpan_unregister_netdev(struct net_device *dev)
72{
73 rtnl_lock();
74 lowpan_unregister_netdevice(dev);
75 rtnl_unlock();
76}
77EXPORT_SYMBOL(lowpan_unregister_netdev);
78
79int addrconf_ifid_802154_6lowpan(u8 *eui, struct net_device *dev)
80{
81 struct wpan_dev *wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr;
82
83 /* Set short_addr autoconfiguration if short_addr is present only */
84 if (!lowpan_802154_is_valid_src_short_addr(addr: wpan_dev->short_addr))
85 return -1;
86
87 /* For either address format, all zero addresses MUST NOT be used */
88 if (wpan_dev->pan_id == cpu_to_le16(0x0000) &&
89 wpan_dev->short_addr == cpu_to_le16(0x0000))
90 return -1;
91
92 /* Alternatively, if no PAN ID is known, 16 zero bits may be used */
93 if (wpan_dev->pan_id == cpu_to_le16(IEEE802154_PAN_ID_BROADCAST))
94 memset(eui, 0, 2);
95 else
96 ieee802154_le16_to_be16(be16_dst: eui, le16_src: &wpan_dev->pan_id);
97
98 /* The "Universal/Local" (U/L) bit shall be set to zero */
99 eui[0] &= ~2;
100 eui[2] = 0;
101 eui[3] = 0xFF;
102 eui[4] = 0xFE;
103 eui[5] = 0;
104 ieee802154_le16_to_be16(be16_dst: &eui[6], le16_src: &wpan_dev->short_addr);
105 return 0;
106}
107
108static int lowpan_event(struct notifier_block *unused,
109 unsigned long event, void *ptr)
110{
111 struct net_device *dev = netdev_notifier_info_to_dev(info: ptr);
112 struct inet6_dev *idev;
113 struct in6_addr addr;
114 int i;
115
116 if (dev->type != ARPHRD_6LOWPAN)
117 return NOTIFY_DONE;
118
119 idev = __in6_dev_get(dev);
120 if (!idev)
121 return NOTIFY_DONE;
122
123 switch (event) {
124 case NETDEV_UP:
125 case NETDEV_CHANGE:
126 /* (802.15.4 6LoWPAN short address slaac handling */
127 if (lowpan_is_ll(dev, lltype: LOWPAN_LLTYPE_IEEE802154) &&
128 addrconf_ifid_802154_6lowpan(eui: addr.s6_addr + 8, dev) == 0) {
129 __ipv6_addr_set_half(addr: &addr.s6_addr32[0],
130 htonl(0xFE800000), wl: 0);
131 addrconf_add_linklocal(idev, addr: &addr, flags: 0);
132 }
133 break;
134 case NETDEV_DOWN:
135 for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++)
136 clear_bit(nr: LOWPAN_IPHC_CTX_FLAG_ACTIVE,
137 addr: &lowpan_dev(dev)->ctx.table[i].flags);
138 break;
139 default:
140 return NOTIFY_DONE;
141 }
142
143 return NOTIFY_OK;
144}
145
146static struct notifier_block lowpan_notifier = {
147 .notifier_call = lowpan_event,
148};
149
150static int __init lowpan_module_init(void)
151{
152 int ret;
153
154 lowpan_debugfs_init();
155
156 ret = register_netdevice_notifier(nb: &lowpan_notifier);
157 if (ret < 0) {
158 lowpan_debugfs_exit();
159 return ret;
160 }
161
162 request_module_nowait("nhc_dest");
163 request_module_nowait("nhc_fragment");
164 request_module_nowait("nhc_hop");
165 request_module_nowait("nhc_ipv6");
166 request_module_nowait("nhc_mobility");
167 request_module_nowait("nhc_routing");
168 request_module_nowait("nhc_udp");
169
170 return 0;
171}
172
173static void __exit lowpan_module_exit(void)
174{
175 lowpan_debugfs_exit();
176 unregister_netdevice_notifier(nb: &lowpan_notifier);
177}
178
179module_init(lowpan_module_init);
180module_exit(lowpan_module_exit);
181
182MODULE_LICENSE("GPL");
183

source code of linux/net/6lowpan/core.c