aboutsummaryrefslogtreecommitdiffstats
path: root/net/6lowpan/ndisc.c
blob: 941df2fa4448952059fad26a9ef75a4a35d98d39 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
/* This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Authors:
 * (C) 2016 Pengutronix, Alexander Aring <aar@pengutronix.de>
 */

#include <net/6lowpan.h>
#include <net/addrconf.h>
#include <net/ndisc.h>

#include "6lowpan_i.h"

static int lowpan_ndisc_is_useropt(u8 nd_opt_type)
{
	return nd_opt_type == ND_OPT_6CO;
}

#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
#define NDISC_802154_SHORT_ADDR_LENGTH	1
static int lowpan_ndisc_parse_802154_options(const struct net_device *dev,
					     struct nd_opt_hdr *nd_opt,
					     struct ndisc_options *ndopts)
{
	switch (nd_opt->nd_opt_len) {
	case NDISC_802154_SHORT_ADDR_LENGTH:
		if (ndopts->nd_802154_opt_array[nd_opt->nd_opt_type])
			ND_PRINTK(2, warn,
				  "%s: duplicated short addr ND6 option found: type=%d\n",
				  __func__, nd_opt->nd_opt_type);
		else
			ndopts->nd_802154_opt_array[nd_opt->nd_opt_type] = nd_opt;
		return 1;
	default:
		/* all others will be handled by ndisc IPv6 option parsing */
		return 0;
	}
}

static int lowpan_ndisc_parse_options(const struct net_device *dev,
				      struct nd_opt_hdr *nd_opt,
				      struct ndisc_options *ndopts)
{
	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return 0;

	switch (nd_opt->nd_opt_type) {
	case ND_OPT_SOURCE_LL_ADDR:
	case ND_OPT_TARGET_LL_ADDR:
		return lowpan_ndisc_parse_802154_options(dev, nd_opt, ndopts);
	default:
		return 0;
	}
}

static void lowpan_ndisc_802154_update(struct neighbour *n, u32 flags,
				       u8 icmp6_type,
				       const struct ndisc_options *ndopts)
{
	struct lowpan_802154_neigh *neigh = lowpan_802154_neigh(neighbour_priv(n));
	u8 *lladdr_short = NULL;

	switch (icmp6_type) {
	case NDISC_ROUTER_SOLICITATION:
	case NDISC_ROUTER_ADVERTISEMENT:
	case NDISC_NEIGHBOUR_SOLICITATION:
		if (ndopts->nd_802154_opts_src_lladdr) {
			lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_src_lladdr,
							     IEEE802154_SHORT_ADDR_LEN, 0);
			if (!lladdr_short) {
				ND_PRINTK(2, warn,
					  "NA: invalid short link-layer address length\n");
				return;
			}
		}
		break;
	case NDISC_REDIRECT:
	case NDISC_NEIGHBOUR_ADVERTISEMENT:
		if (ndopts->nd_802154_opts_tgt_lladdr) {
			lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_tgt_lladdr,
							     IEEE802154_SHORT_ADDR_LEN, 0);
			if (!lladdr_short) {
				ND_PRINTK(2, warn,
					  "NA: invalid short link-layer address length\n");
				return;
			}
		}
		break;
	default:
		break;
	}

	write_lock_bh(&n->lock);
	if (lladdr_short) {
		ieee802154_be16_to_le16(&neigh->short_addr, lladdr_short);
		if (!lowpan_802154_is_valid_src_short_addr(neigh->short_addr))
			neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC);
	}
	write_unlock_bh(&n->lock);
}

static void lowpan_ndisc_update(const struct net_device *dev,
				struct neighbour *n, u32 flags, u8 icmp6_type,
				const struct ndisc_options *ndopts)
{
	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return;

	/* react on overrides only. TODO check if this is really right. */
	if (flags & NEIGH_UPDATE_F_OVERRIDE)
		lowpan_ndisc_802154_update(n, flags, icmp6_type, ndopts);
}

static int lowpan_ndisc_opt_addr_space(const struct net_device *dev,
				       u8 icmp6_type, struct neighbour *neigh,
				       u8 *ha_buf, u8 **ha)
{
	struct lowpan_802154_neigh *n;
	struct wpan_dev *wpan_dev;
	int addr_space = 0;

	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return 0;

	switch (icmp6_type) {
	case NDISC_REDIRECT:
		n = lowpan_802154_neigh(neighbour_priv(neigh));

		read_lock_bh(&neigh->lock);
		if (lowpan_802154_is_valid_src_short_addr(n->short_addr)) {
			memcpy(ha_buf, &n->short_addr,
			       IEEE802154_SHORT_ADDR_LEN);
			read_unlock_bh(&neigh->lock);
			addr_space += __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0);
			*ha = ha_buf;
		} else {
			read_unlock_bh(&neigh->lock);
		}
		break;
	case NDISC_NEIGHBOUR_ADVERTISEMENT:
	case NDISC_NEIGHBOUR_SOLICITATION:
	case NDISC_ROUTER_SOLICITATION:
		wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr;

		if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr))
			addr_space = __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0);
		break;
	default:
		break;
	}

	return addr_space;
}

static void lowpan_ndisc_fill_addr_option(const struct net_device *dev,
					  struct sk_buff *skb, u8 icmp6_type,
					  const u8 *ha)
{
	struct wpan_dev *wpan_dev;
	__be16 short_addr;
	u8 opt_type;

	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return;

	switch (icmp6_type) {
	case NDISC_REDIRECT:
		if (ha) {
			ieee802154_le16_to_be16(&short_addr, ha);
			__ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
						 &short_addr,
						 IEEE802154_SHORT_ADDR_LEN, 0);
		}
		return;
	case NDISC_NEIGHBOUR_ADVERTISEMENT:
		opt_type = ND_OPT_TARGET_LL_ADDR;
		break;
	case NDISC_ROUTER_SOLICITATION:
	case NDISC_NEIGHBOUR_SOLICITATION:
		opt_type = ND_OPT_SOURCE_LL_ADDR;
		break;
	default:
		return;
	}

	wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr;

	if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) {
		ieee802154_le16_to_be16(&short_addr,
					&wpan_dev->short_addr);
		__ndisc_fill_addr_option(skb, opt_type, &short_addr,
					 IEEE802154_SHORT_ADDR_LEN, 0);
	}
}

static void lowpan_ndisc_prefix_rcv_add_addr(struct net *net,
					     struct net_device *dev,
					     const struct prefix_info *pinfo,
					     struct inet6_dev *in6_dev,
					     struct in6_addr *addr,
					     int addr_type, u32 addr_flags,
					     bool sllao, bool tokenized,
					     __u32 valid_lft,
					     u32 prefered_lft,
					     bool dev_addr_generated)
{
	int err;

	/* generates short based address for RA PIO's */
	if (lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154) && dev_addr_generated &&
	    !addrconf_ifid_802154_6lowpan(addr->s6_addr + 8, dev)) {
		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
						   addr, addr_type, addr_flags,
						   sllao, tokenized, valid_lft,
						   prefered_lft);
		if (err)
			ND_PRINTK(2, warn,
				  "RA: could not add a short address based address for prefix: %pI6c\n",
				  &pinfo->prefix);
	}
}
#endif

const struct ndisc_ops lowpan_ndisc_ops = {
	.is_useropt		= lowpan_ndisc_is_useropt,
#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
	.parse_options		= lowpan_ndisc_parse_options,
	.update			= lowpan_ndisc_update,
	.opt_addr_space		= lowpan_ndisc_opt_addr_space,
	.fill_addr_option	= lowpan_ndisc_fill_addr_option,
	.prefix_rcv_add_addr	= lowpan_ndisc_prefix_rcv_add_addr,
#endif
};