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
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* tcp_diag.c Module for monitoring TCP transport protocols sockets.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*/
#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 = READ_ONCE(sk->sk_ack_backlog);
r->idiag_wqueue = READ_ONCE(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, READ_ONCE(tp->rcv_nxt) -
READ_ONCE(tp->copied_seq), 0);
r->idiag_wqueue = READ_ONCE(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_put_ulp(struct sk_buff *skb, struct sock *sk,
const struct tcp_ulp_ops *ulp_ops)
{
struct nlattr *nest;
int err;
nest = nla_nest_start_noflag(skb, INET_DIAG_ULP_INFO);
if (!nest)
return -EMSGSIZE;
err = nla_put_string(skb, INET_ULP_INFO_NAME, ulp_ops->name);
if (err)
goto nla_failure;
if (ulp_ops->get_info)
err = ulp_ops->get_info(sk, skb);
if (err)
goto nla_failure;
nla_nest_end(skb, nest);
return 0;
nla_failure:
nla_nest_cancel(skb, nest);
return err;
}
static int tcp_diag_get_aux(struct sock *sk, bool net_admin,
struct sk_buff *skb)
{
struct inet_connection_sock *icsk = inet_csk(sk);
int err = 0;
#ifdef CONFIG_TCP_MD5SIG
if (net_admin) {
struct tcp_md5sig_info *md5sig;
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
if (net_admin) {
const struct tcp_ulp_ops *ulp_ops;
ulp_ops = icsk->icsk_ulp_ops;
if (ulp_ops)
err = tcp_diag_put_ulp(skb, sk, ulp_ops);
if (err)
return err;
}
return 0;
}
static size_t tcp_diag_get_aux_size(struct sock *sk, bool net_admin)
{
struct inet_connection_sock *icsk = inet_csk(sk);
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
if (net_admin && sk_fullsock(sk)) {
const struct tcp_ulp_ops *ulp_ops;
ulp_ops = icsk->icsk_ulp_ops;
if (ulp_ops) {
size += nla_total_size(0) +
nla_total_size(TCP_ULP_NAME_MAX);
if (ulp_ops->get_info_size)
size += ulp_ops->get_info_size(sk);
}
}
return size;
}
static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
const struct inet_diag_req_v2 *r)
{
struct inet_hashinfo *hinfo;
hinfo = sock_net(cb->skb->sk)->ipv4.tcp_death_row.hashinfo;
inet_diag_dump_icsk(hinfo, skb, cb, r);
}
static int tcp_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
struct inet_hashinfo *hinfo;
hinfo = sock_net(cb->skb->sk)->ipv4.tcp_death_row.hashinfo;
return inet_diag_dump_one_icsk(hinfo, cb, 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 inet_hashinfo *hinfo;
struct sock *sk;
int err;
hinfo = net->ipv4.tcp_death_row.hashinfo;
sk = inet_diag_find_one_icsk(net, hinfo, req);
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_DESCRIPTION("TCP socket monitoring via SOCK_DIAG");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-6 /* AF_INET - IPPROTO_TCP */);
|
