summaryrefslogtreecommitdiffstats
path: root/net/netlink/diag.c
blob: e4f21b1067bccacc86811bd240056de65c470ad9 (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
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/module.h>

#include <net/sock.h>
#include <linux/netlink.h>
#include <linux/sock_diag.h>
#include <linux/netlink_diag.h>
#include <linux/rhashtable.h>

#include "af_netlink.h"

static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
{
	struct netlink_sock *nlk = nlk_sk(sk);

	if (nlk->groups == NULL)
		return 0;

	return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups),
		       nlk->groups);
}

static int sk_diag_put_flags(struct sock *sk, struct sk_buff *skb)
{
	struct netlink_sock *nlk = nlk_sk(sk);
	u32 flags = 0;

	if (nlk->cb_running)
		flags |= NDIAG_FLAG_CB_RUNNING;
	if (nlk->flags & NETLINK_F_RECV_PKTINFO)
		flags |= NDIAG_FLAG_PKTINFO;
	if (nlk->flags & NETLINK_F_BROADCAST_SEND_ERROR)
		flags |= NDIAG_FLAG_BROADCAST_ERROR;
	if (nlk->flags & NETLINK_F_RECV_NO_ENOBUFS)
		flags |= NDIAG_FLAG_NO_ENOBUFS;
	if (nlk->flags & NETLINK_F_LISTEN_ALL_NSID)
		flags |= NDIAG_FLAG_LISTEN_ALL_NSID;
	if (nlk->flags & NETLINK_F_CAP_ACK)
		flags |= NDIAG_FLAG_CAP_ACK;

	return nla_put_u32(skb, NETLINK_DIAG_FLAGS, flags);
}

static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
			struct netlink_diag_req *req,
			u32 portid, u32 seq, u32 flags, int sk_ino)
{
	struct nlmsghdr *nlh;
	struct netlink_diag_msg *rep;
	struct netlink_sock *nlk = nlk_sk(sk);

	nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
			flags);
	if (!nlh)
		return -EMSGSIZE;

	rep = nlmsg_data(nlh);
	rep->ndiag_family	= AF_NETLINK;
	rep->ndiag_type		= sk->sk_type;
	rep->ndiag_protocol	= sk->sk_protocol;
	rep->ndiag_state	= sk->sk_state;

	rep->ndiag_ino		= sk_ino;
	rep->ndiag_portid	= nlk->portid;
	rep->ndiag_dst_portid	= nlk->dst_portid;
	rep->ndiag_dst_group	= nlk->dst_group;
	sock_diag_save_cookie(sk, rep->ndiag_cookie);

	if ((req->ndiag_show & NDIAG_SHOW_GROUPS) &&
	    sk_diag_dump_groups(sk, skb))
		goto out_nlmsg_trim;

	if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) &&
	    sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
		goto out_nlmsg_trim;

	if ((req->ndiag_show & NDIAG_SHOW_FLAGS) &&
	    sk_diag_put_flags(sk, skb))
		goto out_nlmsg_trim;

	nlmsg_end(skb, nlh);
	return 0;

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

static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
				int protocol, int s_num)
{
	struct rhashtable_iter *hti = (void *)cb->args[2];
	struct netlink_table *tbl = &nl_table[protocol];
	struct net *net = sock_net(skb->sk);
	struct netlink_diag_req *req;
	struct netlink_sock *nlsk;
	unsigned long flags;
	struct sock *sk;
	int num = 2;
	int ret = 0;

	req = nlmsg_data(cb->nlh);

	if (s_num > 1)
		goto mc_list;

	num--;

	if (!hti) {
		hti = kmalloc(sizeof(*hti), GFP_KERNEL);
		if (!hti)
			return -ENOMEM;

		cb->args[2] = (long)hti;
	}

	if (!s_num)
		rhashtable_walk_enter(&tbl->hash, hti);

	rhashtable_walk_start(hti);

	while ((nlsk = rhashtable_walk_next(hti))) {
		if (IS_ERR(nlsk)) {
			ret = PTR_ERR(nlsk);
			if (ret == -EAGAIN) {
				ret = 0;
				continue;
			}
			break;
		}

		sk = (struct sock *)nlsk;

		if (!net_eq(sock_net(sk), net))
			continue;

		if (sk_diag_fill(sk, skb, req,
				 NETLINK_CB(cb->skb).portid,
				 cb->nlh->nlmsg_seq,
				 NLM_F_MULTI,
				 sock_i_ino(sk)) < 0) {
			ret = 1;
			break;
		}
	}

	rhashtable_walk_stop(hti);

	if (ret)
		goto done;

	rhashtable_walk_exit(hti);
	num++;

mc_list:
	read_lock_irqsave(&nl_table_lock, flags);
	sk_for_each_bound(sk, &tbl->mc_list) {
		if (sk_hashed(sk))
			continue;
		if (!net_eq(sock_net(sk), net))
			continue;
		if (num < s_num) {
			num++;
			continue;
		}

		if (sk_diag_fill(sk, skb, req,
				 NETLINK_CB(cb->skb).portid,
				 cb->nlh->nlmsg_seq,
				 NLM_F_MULTI,
				 __sock_i_ino(sk)) < 0) {
			ret = 1;
			break;
		}
		num++;
	}
	read_unlock_irqrestore(&nl_table_lock, flags);

done:
	cb->args[0] = num;

	return ret;
}

static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct netlink_diag_req *req;
	int s_num = cb->args[0];
	int err = 0;

	req = nlmsg_data(cb->nlh);

	if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
		int i;

		for (i = cb->args[1]; i < MAX_LINKS; i++) {
			err = __netlink_diag_dump(skb, cb, i, s_num);
			if (err)
				break;
			s_num = 0;
		}
		cb->args[1] = i;
	} else {
		if (req->sdiag_protocol >= MAX_LINKS)
			return -ENOENT;

		err = __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
	}

	return err < 0 ? err : skb->len;
}

static int netlink_diag_dump_done(struct netlink_callback *cb)
{
	struct rhashtable_iter *hti = (void *)cb->args[2];

	if (cb->args[0] == 1)
		rhashtable_walk_exit(hti);

	kfree(hti);

	return 0;
}

static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
{
	int hdrlen = sizeof(struct netlink_diag_req);
	struct net *net = sock_net(skb->sk);

	if (nlmsg_len(h) < hdrlen)
		return -EINVAL;

	if (h->nlmsg_flags & NLM_F_DUMP) {
		struct netlink_dump_control c = {
			.dump = netlink_diag_dump,
			.done = netlink_diag_dump_done,
		};
		return netlink_dump_start(net->diag_nlsk, skb, h, &c);
	} else
		return -EOPNOTSUPP;
}

static const struct sock_diag_handler netlink_diag_handler = {
	.family = AF_NETLINK,
	.dump = netlink_diag_handler_dump,
};

static int __init netlink_diag_init(void)
{
	return sock_diag_register(&netlink_diag_handler);
}

static void __exit netlink_diag_exit(void)
{
	sock_diag_unregister(&netlink_diag_handler);
}

module_init(netlink_diag_init);
module_exit(netlink_diag_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */);