summaryrefslogtreecommitdiffstats
path: root/net/ipv4/tcp_diag.c
blob: 81148f7a2323cf119337927ba881237f83e61492 (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
/*
 * tcp_diag.c	Module for monitoring TCP transport protocols sockets.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

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

#include <linux/tcp.h>

#include <net/netlink.h>
#include <net/tcp.h>

static void tcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
			      void *_info)
{
	struct tcp_info *info = _info;

	if (inet_sk_state_load(sk) == TCP_LISTEN) {
		r->idiag_rqueue = sk->sk_ack_backlog;
		r->idiag_wqueue = sk->sk_max_ack_backlog;
	} else if (sk->sk_type == SOCK_STREAM) {
		const struct tcp_sock *tp = tcp_sk(sk);

		r->idiag_rqueue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
		r->idiag_wqueue = tp->write_seq - tp->snd_una;
	}
	if (info)
		tcp_get_info(sk, info);
}

#ifdef CONFIG_TCP_MD5SIG
static void tcp_diag_md5sig_fill(struct tcp_diag_md5sig *info,
				 const struct tcp_md5sig_key *key)
{
	info->tcpm_family = key->family;
	info->tcpm_prefixlen = key->prefixlen;
	info->tcpm_keylen = key->keylen;
	memcpy(info->tcpm_key, key->key, key->keylen);

	if (key->family == AF_INET)
		info->tcpm_addr[0] = key->addr.a4.s_addr;
	#if IS_ENABLED(CONFIG_IPV6)
	else if (key->family == AF_INET6)
		memcpy(&info->tcpm_addr, &key->addr.a6,
		       sizeof(info->tcpm_addr));
	#endif
}

static int tcp_diag_put_md5sig(struct sk_buff *skb,
			       const struct tcp_md5sig_info *md5sig)
{
	const struct tcp_md5sig_key *key;
	struct tcp_diag_md5sig *info;
	struct nlattr *attr;
	int md5sig_count = 0;

	hlist_for_each_entry_rcu(key, &md5sig->head, node)
		md5sig_count++;
	if (md5sig_count == 0)
		return 0;

	attr = nla_reserve(skb, INET_DIAG_MD5SIG,
			   md5sig_count * sizeof(struct tcp_diag_md5sig));
	if (!attr)
		return -EMSGSIZE;

	info = nla_data(attr);
	memset(info, 0, md5sig_count * sizeof(struct tcp_diag_md5sig));
	hlist_for_each_entry_rcu(key, &md5sig->head, node) {
		tcp_diag_md5sig_fill(info++, key);
		if (--md5sig_count == 0)
			break;
	}

	return 0;
}
#endif

static int tcp_diag_get_aux(struct sock *sk, bool net_admin,
			    struct sk_buff *skb)
{
#ifdef CONFIG_TCP_MD5SIG
	if (net_admin) {
		struct tcp_md5sig_info *md5sig;
		int err = 0;

		rcu_read_lock();
		md5sig = rcu_dereference(tcp_sk(sk)->md5sig_info);
		if (md5sig)
			err = tcp_diag_put_md5sig(skb, md5sig);
		rcu_read_unlock();
		if (err < 0)
			return err;
	}
#endif

	return 0;
}

static size_t tcp_diag_get_aux_size(struct sock *sk, bool net_admin)
{
	size_t size = 0;

#ifdef CONFIG_TCP_MD5SIG
	if (net_admin && sk_fullsock(sk)) {
		const struct tcp_md5sig_info *md5sig;
		const struct tcp_md5sig_key *key;
		size_t md5sig_count = 0;

		rcu_read_lock();
		md5sig = rcu_dereference(tcp_sk(sk)->md5sig_info);
		if (md5sig) {
			hlist_for_each_entry_rcu(key, &md5sig->head, node)
				md5sig_count++;
		}
		rcu_read_unlock();
		size += nla_total_size(md5sig_count *
				       sizeof(struct tcp_diag_md5sig));
	}
#endif

	return size;
}

static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
			  const struct inet_diag_req_v2 *r, struct nlattr *bc)
{
	inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r, bc);
}

static int tcp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
			     const struct inet_diag_req_v2 *req)
{
	return inet_diag_dump_one_icsk(&tcp_hashinfo, in_skb, nlh, req);
}

#ifdef CONFIG_INET_DIAG_DESTROY
static int tcp_diag_destroy(struct sk_buff *in_skb,
			    const struct inet_diag_req_v2 *req)
{
	struct net *net = sock_net(in_skb->sk);
	struct sock *sk = inet_diag_find_one_icsk(net, &tcp_hashinfo, req);
	int err;

	if (IS_ERR(sk))
		return PTR_ERR(sk);

	err = sock_diag_destroy(sk, ECONNABORTED);

	sock_gen_put(sk);

	return err;
}
#endif

static const struct inet_diag_handler tcp_diag_handler = {
	.dump			= tcp_diag_dump,
	.dump_one		= tcp_diag_dump_one,
	.idiag_get_info		= tcp_diag_get_info,
	.idiag_get_aux		= tcp_diag_get_aux,
	.idiag_get_aux_size	= tcp_diag_get_aux_size,
	.idiag_type		= IPPROTO_TCP,
	.idiag_info_size	= sizeof(struct tcp_info),
#ifdef CONFIG_INET_DIAG_DESTROY
	.destroy		= tcp_diag_destroy,
#endif
};

static int __init tcp_diag_init(void)
{
	return inet_diag_register(&tcp_diag_handler);
}

static void __exit tcp_diag_exit(void)
{
	inet_diag_unregister(&tcp_diag_handler);
}

module_init(tcp_diag_init);
module_exit(tcp_diag_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-6 /* AF_INET - IPPROTO_TCP */);