summaryrefslogtreecommitdiffstats
path: root/net/ipv4/udp_diag.c
blob: dc41a22ee80e829582349e8e644f204eff07df0e (plain)
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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * udp_diag.c	Module for monitoring UDP transport protocols sockets.
 *
 * Authors:	Pavel Emelyanov, <xemul@parallels.com>
 */


#include <linux/module.h>
#include <linux/inet_diag.h>
#include <linux/udp.h>
#include <net/udp.h>
#include <net/udplite.h>
#include <linux/sock_diag.h>

static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
			struct netlink_callback *cb,
			const struct inet_diag_req_v2 *req,
			struct nlattr *bc, bool net_admin)
{
	if (!inet_diag_bc_sk(bc, sk))
		return 0;

	return inet_sk_diag_fill(sk, NULL, skb, cb, req, NLM_F_MULTI,
				 net_admin);
}

static int udp_dump_one(struct udp_table *tbl,
			struct netlink_callback *cb,
			const struct inet_diag_req_v2 *req)
{
	struct sk_buff *in_skb = cb->skb;
	int err;
	struct sock *sk = NULL;
	struct sk_buff *rep;
	struct net *net = sock_net(in_skb->sk);

	rcu_read_lock();
	if (req->sdiag_family == AF_INET)
		/* src and dst are swapped for historical reasons */
		sk = __udp4_lib_lookup(net,
				req->id.idiag_src[0], req->id.idiag_sport,
				req->id.idiag_dst[0], req->id.idiag_dport,
				req->id.idiag_if, 0, tbl, NULL);
#if IS_ENABLED(CONFIG_IPV6)
	else if (req->sdiag_family == AF_INET6)
		sk = __udp6_lib_lookup(net,
				(struct in6_addr *)req->id.idiag_src,
				req->id.idiag_sport,
				(struct in6_addr *)req->id.idiag_dst,
				req->id.idiag_dport,
				req->id.idiag_if, 0, tbl, NULL);
#endif
	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
		sk = NULL;
	rcu_read_unlock();
	err = -ENOENT;
	if (!sk)
		goto out_nosk;

	err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
	if (err)
		goto out;

	err = -ENOMEM;
	rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
			inet_diag_msg_attrs_size() +
			nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
			GFP_KERNEL);
	if (!rep)
		goto out;

	err = inet_sk_diag_fill(sk, NULL, rep, cb, req, 0,
				netlink_net_capable(in_skb, CAP_NET_ADMIN));
	if (err < 0) {
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(rep);
		goto out;
	}
	err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);

out:
	if (sk)
		sock_put(sk);
out_nosk:
	return err;
}

static void udp_dump(struct udp_table *table, struct sk_buff *skb,
		     struct netlink_callback *cb,
		     const struct inet_diag_req_v2 *r)
{
	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
	struct net *net = sock_net(skb->sk);
	struct inet_diag_dump_data *cb_data;
	int num, s_num, slot, s_slot;
	struct nlattr *bc;

	cb_data = cb->data;
	bc = cb_data->inet_diag_nla_bc;
	s_slot = cb->args[0];
	num = s_num = cb->args[1];

	for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) {
		struct udp_hslot *hslot = &table->hash[slot];
		struct sock *sk;

		num = 0;

		if (hlist_empty(&hslot->head))
			continue;

		spin_lock_bh(&hslot->lock);
		sk_for_each(sk, &hslot->head) {
			struct inet_sock *inet = inet_sk(sk);

			if (!net_eq(sock_net(sk), net))
				continue;
			if (num < s_num)
				goto next;
			if (!(r->idiag_states & (1 << sk->sk_state)))
				goto next;
			if (r->sdiag_family != AF_UNSPEC &&
					sk->sk_family != r->sdiag_family)
				goto next;
			if (r->id.idiag_sport != inet->inet_sport &&
			    r->id.idiag_sport)
				goto next;
			if (r->id.idiag_dport != inet->inet_dport &&
			    r->id.idiag_dport)
				goto next;

			if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
				spin_unlock_bh(&hslot->lock);
				goto done;
			}
next:
			num++;
		}
		spin_unlock_bh(&hslot->lock);
	}
done:
	cb->args[0] = slot;
	cb->args[1] = num;
}

static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
			  const struct inet_diag_req_v2 *r)
{
	udp_dump(sock_net(cb->skb->sk)->ipv4.udp_table, skb, cb, r);
}

static int udp_diag_dump_one(struct netlink_callback *cb,
			     const struct inet_diag_req_v2 *req)
{
	return udp_dump_one(sock_net(cb->skb->sk)->ipv4.udp_table, cb, req);
}

static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
		void *info)
{
	r->idiag_rqueue = udp_rqueue_get(sk);
	r->idiag_wqueue = sk_wmem_alloc_get(sk);
}

#ifdef CONFIG_INET_DIAG_DESTROY
static int __udp_diag_destroy(struct sk_buff *in_skb,
			      const struct inet_diag_req_v2 *req,
			      struct udp_table *tbl)
{
	struct net *net = sock_net(in_skb->sk);
	struct sock *sk;
	int err;

	rcu_read_lock();

	if (req->sdiag_family == AF_INET)
		sk = __udp4_lib_lookup(net,
				req->id.idiag_dst[0], req->id.idiag_dport,
				req->id.idiag_src[0], req->id.idiag_sport,
				req->id.idiag_if, 0, tbl, NULL);
#if IS_ENABLED(CONFIG_IPV6)
	else if (req->sdiag_family == AF_INET6) {
		if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
		    ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
			sk = __udp4_lib_lookup(net,
					req->id.idiag_dst[3], req->id.idiag_dport,
					req->id.idiag_src[3], req->id.idiag_sport,
					req->id.idiag_if, 0, tbl, NULL);

		else
			sk = __udp6_lib_lookup(net,
					(struct in6_addr *)req->id.idiag_dst,
					req->id.idiag_dport,
					(struct in6_addr *)req->id.idiag_src,
					req->id.idiag_sport,
					req->id.idiag_if, 0, tbl, NULL);
	}
#endif
	else {
		rcu_read_unlock();
		return -EINVAL;
	}

	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
		sk = NULL;

	rcu_read_unlock();

	if (!sk)
		return -ENOENT;

	if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
		sock_put(sk);
		return -ENOENT;
	}

	err = sock_diag_destroy(sk, ECONNABORTED);

	sock_put(sk);

	return err;
}

static int udp_diag_destroy(struct sk_buff *in_skb,
			    const struct inet_diag_req_v2 *req)
{
	return __udp_diag_destroy(in_skb, req, sock_net(in_skb->sk)->ipv4.udp_table);
}

static int udplite_diag_destroy(struct sk_buff *in_skb,
				const struct inet_diag_req_v2 *req)
{
	return __udp_diag_destroy(in_skb, req, &udplite_table);
}

#endif

static const struct inet_diag_handler udp_diag_handler = {
	.dump		 = udp_diag_dump,
	.dump_one	 = udp_diag_dump_one,
	.idiag_get_info  = udp_diag_get_info,
	.idiag_type	 = IPPROTO_UDP,
	.idiag_info_size = 0,
#ifdef CONFIG_INET_DIAG_DESTROY
	.destroy	 = udp_diag_destroy,
#endif
};

static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
			      const struct inet_diag_req_v2 *r)
{
	udp_dump(&udplite_table, skb, cb, r);
}

static int udplite_diag_dump_one(struct netlink_callback *cb,
				 const struct inet_diag_req_v2 *req)
{
	return udp_dump_one(&udplite_table, cb, req);
}

static const struct inet_diag_handler udplite_diag_handler = {
	.dump		 = udplite_diag_dump,
	.dump_one	 = udplite_diag_dump_one,
	.idiag_get_info  = udp_diag_get_info,
	.idiag_type	 = IPPROTO_UDPLITE,
	.idiag_info_size = 0,
#ifdef CONFIG_INET_DIAG_DESTROY
	.destroy	 = udplite_diag_destroy,
#endif
};

static int __init udp_diag_init(void)
{
	int err;

	err = inet_diag_register(&udp_diag_handler);
	if (err)
		goto out;
	err = inet_diag_register(&udplite_diag_handler);
	if (err)
		goto out_lite;
out:
	return err;
out_lite:
	inet_diag_unregister(&udp_diag_handler);
	goto out;
}

static void __exit udp_diag_exit(void)
{
	inet_diag_unregister(&udplite_diag_handler);
	inet_diag_unregister(&udp_diag_handler);
}

module_init(udp_diag_init);
module_exit(udp_diag_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("UDP socket monitoring via SOCK_DIAG");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);