summaryrefslogtreecommitdiffstats
path: root/net/phonet/pn_netlink.c
blob: 59aebe29689077bfa77d37516aea4617fe3b8a50 (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
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
// SPDX-License-Identifier: GPL-2.0-only
/*
 * File: pn_netlink.c
 *
 * Phonet netlink interface
 *
 * Copyright (C) 2008 Nokia Corporation.
 *
 * Authors: Sakari Ailus <sakari.ailus@nokia.com>
 *          Remi Denis-Courmont
 */

#include <linux/kernel.h>
#include <linux/netlink.h>
#include <linux/phonet.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/phonet/pn_dev.h>

/* Device address handling */

static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr,
		     u32 portid, u32 seq, int event);

void phonet_address_notify(int event, struct net_device *dev, u8 addr)
{
	struct sk_buff *skb;
	int err = -ENOBUFS;

	skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) +
			nla_total_size(1), GFP_KERNEL);
	if (skb == NULL)
		goto errout;
	err = fill_addr(skb, dev, addr, 0, 0, event);
	if (err < 0) {
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
	rtnl_notify(skb, dev_net(dev), 0,
		    RTNLGRP_PHONET_IFADDR, NULL, GFP_KERNEL);
	return;
errout:
	rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_IFADDR, err);
}

static const struct nla_policy ifa_phonet_policy[IFA_MAX+1] = {
	[IFA_LOCAL] = { .type = NLA_U8 },
};

static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
		     struct netlink_ext_ack *extack)
{
	struct net *net = sock_net(skb->sk);
	struct nlattr *tb[IFA_MAX+1];
	struct net_device *dev;
	struct ifaddrmsg *ifm;
	int err;
	u8 pnaddr;

	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;

	if (!netlink_capable(skb, CAP_SYS_ADMIN))
		return -EPERM;

	ASSERT_RTNL();

	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
				     ifa_phonet_policy, extack);
	if (err < 0)
		return err;

	ifm = nlmsg_data(nlh);
	if (tb[IFA_LOCAL] == NULL)
		return -EINVAL;
	pnaddr = nla_get_u8(tb[IFA_LOCAL]);
	if (pnaddr & 3)
		/* Phonet addresses only have 6 high-order bits */
		return -EINVAL;

	dev = __dev_get_by_index(net, ifm->ifa_index);
	if (dev == NULL)
		return -ENODEV;

	if (nlh->nlmsg_type == RTM_NEWADDR)
		err = phonet_address_add(dev, pnaddr);
	else
		err = phonet_address_del(dev, pnaddr);
	if (!err)
		phonet_address_notify(nlh->nlmsg_type, dev, pnaddr);
	return err;
}

static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr,
			u32 portid, u32 seq, int event)
{
	struct ifaddrmsg *ifm;
	struct nlmsghdr *nlh;

	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), 0);
	if (nlh == NULL)
		return -EMSGSIZE;

	ifm = nlmsg_data(nlh);
	ifm->ifa_family = AF_PHONET;
	ifm->ifa_prefixlen = 0;
	ifm->ifa_flags = IFA_F_PERMANENT;
	ifm->ifa_scope = RT_SCOPE_LINK;
	ifm->ifa_index = dev->ifindex;
	if (nla_put_u8(skb, IFA_LOCAL, addr))
		goto nla_put_failure;
	nlmsg_end(skb, nlh);
	return 0;

nla_put_failure:
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
}

static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct phonet_device_list *pndevs;
	struct phonet_device *pnd;
	int dev_idx = 0, dev_start_idx = cb->args[0];
	int addr_idx = 0, addr_start_idx = cb->args[1];

	pndevs = phonet_device_list(sock_net(skb->sk));
	rcu_read_lock();
	list_for_each_entry_rcu(pnd, &pndevs->list, list) {
		u8 addr;

		if (dev_idx > dev_start_idx)
			addr_start_idx = 0;
		if (dev_idx++ < dev_start_idx)
			continue;

		addr_idx = 0;
		for_each_set_bit(addr, pnd->addrs, 64) {
			if (addr_idx++ < addr_start_idx)
				continue;

			if (fill_addr(skb, pnd->netdev, addr << 2,
					 NETLINK_CB(cb->skb).portid,
					cb->nlh->nlmsg_seq, RTM_NEWADDR) < 0)
				goto out;
		}
	}

out:
	rcu_read_unlock();
	cb->args[0] = dev_idx;
	cb->args[1] = addr_idx;

	return skb->len;
}

/* Routes handling */

static int fill_route(struct sk_buff *skb, struct net_device *dev, u8 dst,
			u32 portid, u32 seq, int event)
{
	struct rtmsg *rtm;
	struct nlmsghdr *nlh;

	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), 0);
	if (nlh == NULL)
		return -EMSGSIZE;

	rtm = nlmsg_data(nlh);
	rtm->rtm_family = AF_PHONET;
	rtm->rtm_dst_len = 6;
	rtm->rtm_src_len = 0;
	rtm->rtm_tos = 0;
	rtm->rtm_table = RT_TABLE_MAIN;
	rtm->rtm_protocol = RTPROT_STATIC;
	rtm->rtm_scope = RT_SCOPE_UNIVERSE;
	rtm->rtm_type = RTN_UNICAST;
	rtm->rtm_flags = 0;
	if (nla_put_u8(skb, RTA_DST, dst) ||
	    nla_put_u32(skb, RTA_OIF, dev->ifindex))
		goto nla_put_failure;
	nlmsg_end(skb, nlh);
	return 0;

nla_put_failure:
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
}

void rtm_phonet_notify(int event, struct net_device *dev, u8 dst)
{
	struct sk_buff *skb;
	int err = -ENOBUFS;

	skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) +
			nla_total_size(1) + nla_total_size(4), GFP_KERNEL);
	if (skb == NULL)
		goto errout;
	err = fill_route(skb, dev, dst, 0, 0, event);
	if (err < 0) {
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
	rtnl_notify(skb, dev_net(dev), 0,
			  RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL);
	return;
errout:
	rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_ROUTE, err);
}

static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = {
	[RTA_DST] = { .type = NLA_U8 },
	[RTA_OIF] = { .type = NLA_U32 },
};

static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
		      struct netlink_ext_ack *extack)
{
	struct net *net = sock_net(skb->sk);
	struct nlattr *tb[RTA_MAX+1];
	struct net_device *dev;
	struct rtmsg *rtm;
	int err;
	u8 dst;

	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;

	if (!netlink_capable(skb, CAP_SYS_ADMIN))
		return -EPERM;

	ASSERT_RTNL();

	err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
				     rtm_phonet_policy, extack);
	if (err < 0)
		return err;

	rtm = nlmsg_data(nlh);
	if (rtm->rtm_table != RT_TABLE_MAIN || rtm->rtm_type != RTN_UNICAST)
		return -EINVAL;
	if (tb[RTA_DST] == NULL || tb[RTA_OIF] == NULL)
		return -EINVAL;
	dst = nla_get_u8(tb[RTA_DST]);
	if (dst & 3) /* Phonet addresses only have 6 high-order bits */
		return -EINVAL;

	dev = __dev_get_by_index(net, nla_get_u32(tb[RTA_OIF]));
	if (dev == NULL)
		return -ENODEV;

	if (nlh->nlmsg_type == RTM_NEWROUTE)
		err = phonet_route_add(dev, dst);
	else
		err = phonet_route_del(dev, dst);
	if (!err)
		rtm_phonet_notify(nlh->nlmsg_type, dev, dst);
	return err;
}

static int route_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct net *net = sock_net(skb->sk);
	u8 addr;

	rcu_read_lock();
	for (addr = cb->args[0]; addr < 64; addr++) {
		struct net_device *dev = phonet_route_get_rcu(net, addr << 2);

		if (!dev)
			continue;

		if (fill_route(skb, dev, addr << 2, NETLINK_CB(cb->skb).portid,
			       cb->nlh->nlmsg_seq, RTM_NEWROUTE) < 0)
			goto out;
	}

out:
	rcu_read_unlock();
	cb->args[0] = addr;

	return skb->len;
}

int __init phonet_netlink_register(void)
{
	int err = rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_NEWADDR,
				       addr_doit, NULL, 0);
	if (err)
		return err;

	/* Further rtnl_register_module() cannot fail */
	rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_DELADDR,
			     addr_doit, NULL, 0);
	rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_GETADDR,
			     NULL, getaddr_dumpit, 0);
	rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_NEWROUTE,
			     route_doit, NULL, 0);
	rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_DELROUTE,
			     route_doit, NULL, 0);
	rtnl_register_module(THIS_MODULE, PF_PHONET, RTM_GETROUTE,
			     NULL, route_dumpit, 0);
	return 0;
}