12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
217b085eaSArnaldo Carvalho de Melo /*
317b085eaSArnaldo Carvalho de Melo * tcp_diag.c Module for monitoring TCP transport protocols sockets.
417b085eaSArnaldo Carvalho de Melo *
517b085eaSArnaldo Carvalho de Melo * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
617b085eaSArnaldo Carvalho de Melo */
717b085eaSArnaldo Carvalho de Melo
817b085eaSArnaldo Carvalho de Melo #include <linux/module.h>
9c1e64e29SLorenzo Colitti #include <linux/net.h>
10c1e64e29SLorenzo Colitti #include <linux/sock_diag.h>
1117b085eaSArnaldo Carvalho de Melo #include <linux/inet_diag.h>
1217b085eaSArnaldo Carvalho de Melo
1317b085eaSArnaldo Carvalho de Melo #include <linux/tcp.h>
1417b085eaSArnaldo Carvalho de Melo
15c03fa9bcSIvan Delalande #include <net/netlink.h>
1617b085eaSArnaldo Carvalho de Melo #include <net/tcp.h>
1717b085eaSArnaldo Carvalho de Melo
tcp_diag_get_info(struct sock * sk,struct inet_diag_msg * r,void * _info)1817b085eaSArnaldo Carvalho de Melo static void tcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
1917b085eaSArnaldo Carvalho de Melo void *_info)
2017b085eaSArnaldo Carvalho de Melo {
2117b085eaSArnaldo Carvalho de Melo struct tcp_info *info = _info;
2217b085eaSArnaldo Carvalho de Melo
23986ffdfdSYafang Shao if (inet_sk_state_load(sk) == TCP_LISTEN) {
24288efe86SEric Dumazet r->idiag_rqueue = READ_ONCE(sk->sk_ack_backlog);
25099ecf59SEric Dumazet r->idiag_wqueue = READ_ONCE(sk->sk_max_ack_backlog);
2635ac838aSCraig Gallek } else if (sk->sk_type == SOCK_STREAM) {
2735ac838aSCraig Gallek const struct tcp_sock *tp = tcp_sk(sk);
2835ac838aSCraig Gallek
297db48e98SEric Dumazet r->idiag_rqueue = max_t(int, READ_ONCE(tp->rcv_nxt) -
307db48e98SEric Dumazet READ_ONCE(tp->copied_seq), 0);
310f317464SEric Dumazet r->idiag_wqueue = READ_ONCE(tp->write_seq) - tp->snd_una;
325ee3afbaSRick Jones }
3300db4124SIan Morris if (info)
3417b085eaSArnaldo Carvalho de Melo tcp_get_info(sk, info);
3517b085eaSArnaldo Carvalho de Melo }
3617b085eaSArnaldo Carvalho de Melo
37c03fa9bcSIvan Delalande #ifdef CONFIG_TCP_MD5SIG
tcp_diag_md5sig_fill(struct tcp_diag_md5sig * info,const struct tcp_md5sig_key * key)38c03fa9bcSIvan Delalande static void tcp_diag_md5sig_fill(struct tcp_diag_md5sig *info,
39c03fa9bcSIvan Delalande const struct tcp_md5sig_key *key)
40c03fa9bcSIvan Delalande {
41c03fa9bcSIvan Delalande info->tcpm_family = key->family;
42c03fa9bcSIvan Delalande info->tcpm_prefixlen = key->prefixlen;
43c03fa9bcSIvan Delalande info->tcpm_keylen = key->keylen;
44c03fa9bcSIvan Delalande memcpy(info->tcpm_key, key->key, key->keylen);
45c03fa9bcSIvan Delalande
46c03fa9bcSIvan Delalande if (key->family == AF_INET)
47c03fa9bcSIvan Delalande info->tcpm_addr[0] = key->addr.a4.s_addr;
48c03fa9bcSIvan Delalande #if IS_ENABLED(CONFIG_IPV6)
49c03fa9bcSIvan Delalande else if (key->family == AF_INET6)
50c03fa9bcSIvan Delalande memcpy(&info->tcpm_addr, &key->addr.a6,
51c03fa9bcSIvan Delalande sizeof(info->tcpm_addr));
52c03fa9bcSIvan Delalande #endif
53c03fa9bcSIvan Delalande }
54c03fa9bcSIvan Delalande
tcp_diag_put_md5sig(struct sk_buff * skb,const struct tcp_md5sig_info * md5sig)55c03fa9bcSIvan Delalande static int tcp_diag_put_md5sig(struct sk_buff *skb,
56c03fa9bcSIvan Delalande const struct tcp_md5sig_info *md5sig)
57c03fa9bcSIvan Delalande {
58c03fa9bcSIvan Delalande const struct tcp_md5sig_key *key;
59c03fa9bcSIvan Delalande struct tcp_diag_md5sig *info;
60c03fa9bcSIvan Delalande struct nlattr *attr;
61c03fa9bcSIvan Delalande int md5sig_count = 0;
62c03fa9bcSIvan Delalande
63c03fa9bcSIvan Delalande hlist_for_each_entry_rcu(key, &md5sig->head, node)
64c03fa9bcSIvan Delalande md5sig_count++;
65c03fa9bcSIvan Delalande if (md5sig_count == 0)
66c03fa9bcSIvan Delalande return 0;
67c03fa9bcSIvan Delalande
68c03fa9bcSIvan Delalande attr = nla_reserve(skb, INET_DIAG_MD5SIG,
69c03fa9bcSIvan Delalande md5sig_count * sizeof(struct tcp_diag_md5sig));
70c03fa9bcSIvan Delalande if (!attr)
71c03fa9bcSIvan Delalande return -EMSGSIZE;
72c03fa9bcSIvan Delalande
73c03fa9bcSIvan Delalande info = nla_data(attr);
74c03fa9bcSIvan Delalande memset(info, 0, md5sig_count * sizeof(struct tcp_diag_md5sig));
75c03fa9bcSIvan Delalande hlist_for_each_entry_rcu(key, &md5sig->head, node) {
76c03fa9bcSIvan Delalande tcp_diag_md5sig_fill(info++, key);
77c03fa9bcSIvan Delalande if (--md5sig_count == 0)
78c03fa9bcSIvan Delalande break;
79c03fa9bcSIvan Delalande }
80c03fa9bcSIvan Delalande
81c03fa9bcSIvan Delalande return 0;
82c03fa9bcSIvan Delalande }
83c03fa9bcSIvan Delalande #endif
84c03fa9bcSIvan Delalande
tcp_diag_put_ulp(struct sk_buff * skb,struct sock * sk,const struct tcp_ulp_ops * ulp_ops)8561723b39SDavide Caratti static int tcp_diag_put_ulp(struct sk_buff *skb, struct sock *sk,
8661723b39SDavide Caratti const struct tcp_ulp_ops *ulp_ops)
8761723b39SDavide Caratti {
8861723b39SDavide Caratti struct nlattr *nest;
8961723b39SDavide Caratti int err;
9061723b39SDavide Caratti
9161723b39SDavide Caratti nest = nla_nest_start_noflag(skb, INET_DIAG_ULP_INFO);
9261723b39SDavide Caratti if (!nest)
9361723b39SDavide Caratti return -EMSGSIZE;
9461723b39SDavide Caratti
9561723b39SDavide Caratti err = nla_put_string(skb, INET_ULP_INFO_NAME, ulp_ops->name);
9661723b39SDavide Caratti if (err)
9761723b39SDavide Caratti goto nla_failure;
9861723b39SDavide Caratti
9961723b39SDavide Caratti if (ulp_ops->get_info)
10061723b39SDavide Caratti err = ulp_ops->get_info(sk, skb);
10161723b39SDavide Caratti if (err)
10261723b39SDavide Caratti goto nla_failure;
10361723b39SDavide Caratti
10461723b39SDavide Caratti nla_nest_end(skb, nest);
10561723b39SDavide Caratti return 0;
10661723b39SDavide Caratti
10761723b39SDavide Caratti nla_failure:
10861723b39SDavide Caratti nla_nest_cancel(skb, nest);
10961723b39SDavide Caratti return err;
11061723b39SDavide Caratti }
11161723b39SDavide Caratti
tcp_diag_get_aux(struct sock * sk,bool net_admin,struct sk_buff * skb)112c03fa9bcSIvan Delalande static int tcp_diag_get_aux(struct sock *sk, bool net_admin,
113c03fa9bcSIvan Delalande struct sk_buff *skb)
114c03fa9bcSIvan Delalande {
11561723b39SDavide Caratti struct inet_connection_sock *icsk = inet_csk(sk);
11661723b39SDavide Caratti int err = 0;
11761723b39SDavide Caratti
118c03fa9bcSIvan Delalande #ifdef CONFIG_TCP_MD5SIG
119c03fa9bcSIvan Delalande if (net_admin) {
120c03fa9bcSIvan Delalande struct tcp_md5sig_info *md5sig;
121c03fa9bcSIvan Delalande
122c03fa9bcSIvan Delalande rcu_read_lock();
123c03fa9bcSIvan Delalande md5sig = rcu_dereference(tcp_sk(sk)->md5sig_info);
124c03fa9bcSIvan Delalande if (md5sig)
125c03fa9bcSIvan Delalande err = tcp_diag_put_md5sig(skb, md5sig);
126c03fa9bcSIvan Delalande rcu_read_unlock();
127c03fa9bcSIvan Delalande if (err < 0)
128c03fa9bcSIvan Delalande return err;
129c03fa9bcSIvan Delalande }
130c03fa9bcSIvan Delalande #endif
131c03fa9bcSIvan Delalande
13261723b39SDavide Caratti if (net_admin) {
13361723b39SDavide Caratti const struct tcp_ulp_ops *ulp_ops;
13461723b39SDavide Caratti
13561723b39SDavide Caratti ulp_ops = icsk->icsk_ulp_ops;
13661723b39SDavide Caratti if (ulp_ops)
13761723b39SDavide Caratti err = tcp_diag_put_ulp(skb, sk, ulp_ops);
13861723b39SDavide Caratti if (err)
13961723b39SDavide Caratti return err;
14061723b39SDavide Caratti }
141c03fa9bcSIvan Delalande return 0;
142c03fa9bcSIvan Delalande }
143c03fa9bcSIvan Delalande
tcp_diag_get_aux_size(struct sock * sk,bool net_admin)144c03fa9bcSIvan Delalande static size_t tcp_diag_get_aux_size(struct sock *sk, bool net_admin)
145c03fa9bcSIvan Delalande {
14661723b39SDavide Caratti struct inet_connection_sock *icsk = inet_csk(sk);
147c03fa9bcSIvan Delalande size_t size = 0;
148c03fa9bcSIvan Delalande
149c03fa9bcSIvan Delalande #ifdef CONFIG_TCP_MD5SIG
150c03fa9bcSIvan Delalande if (net_admin && sk_fullsock(sk)) {
151c03fa9bcSIvan Delalande const struct tcp_md5sig_info *md5sig;
152c03fa9bcSIvan Delalande const struct tcp_md5sig_key *key;
153c03fa9bcSIvan Delalande size_t md5sig_count = 0;
154c03fa9bcSIvan Delalande
155c03fa9bcSIvan Delalande rcu_read_lock();
156c03fa9bcSIvan Delalande md5sig = rcu_dereference(tcp_sk(sk)->md5sig_info);
157c03fa9bcSIvan Delalande if (md5sig) {
158c03fa9bcSIvan Delalande hlist_for_each_entry_rcu(key, &md5sig->head, node)
159c03fa9bcSIvan Delalande md5sig_count++;
160c03fa9bcSIvan Delalande }
161c03fa9bcSIvan Delalande rcu_read_unlock();
162c03fa9bcSIvan Delalande size += nla_total_size(md5sig_count *
163c03fa9bcSIvan Delalande sizeof(struct tcp_diag_md5sig));
164c03fa9bcSIvan Delalande }
165c03fa9bcSIvan Delalande #endif
166c03fa9bcSIvan Delalande
167b58662a5SEric Dumazet if (net_admin && sk_fullsock(sk)) {
16861723b39SDavide Caratti const struct tcp_ulp_ops *ulp_ops;
16961723b39SDavide Caratti
17061723b39SDavide Caratti ulp_ops = icsk->icsk_ulp_ops;
17161723b39SDavide Caratti if (ulp_ops) {
17261723b39SDavide Caratti size += nla_total_size(0) +
17361723b39SDavide Caratti nla_total_size(TCP_ULP_NAME_MAX);
17461723b39SDavide Caratti if (ulp_ops->get_info_size)
17561723b39SDavide Caratti size += ulp_ops->get_info_size(sk);
17661723b39SDavide Caratti }
17761723b39SDavide Caratti }
178c03fa9bcSIvan Delalande return size;
179c03fa9bcSIvan Delalande }
180c03fa9bcSIvan Delalande
tcp_diag_dump(struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r)1811942c518SPavel Emelyanov static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
1820df6d328SMartin KaFai Lau const struct inet_diag_req_v2 *r)
1831942c518SPavel Emelyanov {
1844461568aSKuniyuki Iwashima struct inet_hashinfo *hinfo;
1854461568aSKuniyuki Iwashima
1864461568aSKuniyuki Iwashima hinfo = sock_net(cb->skb->sk)->ipv4.tcp_death_row.hashinfo;
1874461568aSKuniyuki Iwashima
1884461568aSKuniyuki Iwashima inet_diag_dump_icsk(hinfo, skb, cb, r);
1891942c518SPavel Emelyanov }
1901942c518SPavel Emelyanov
tcp_diag_dump_one(struct netlink_callback * cb,const struct inet_diag_req_v2 * req)1915682d393SMartin KaFai Lau static int tcp_diag_dump_one(struct netlink_callback *cb,
19234160ea3SEric Dumazet const struct inet_diag_req_v2 *req)
1931942c518SPavel Emelyanov {
1944461568aSKuniyuki Iwashima struct inet_hashinfo *hinfo;
1954461568aSKuniyuki Iwashima
1964461568aSKuniyuki Iwashima hinfo = sock_net(cb->skb->sk)->ipv4.tcp_death_row.hashinfo;
1974461568aSKuniyuki Iwashima
1984461568aSKuniyuki Iwashima return inet_diag_dump_one_icsk(hinfo, cb, req);
1991942c518SPavel Emelyanov }
2001942c518SPavel Emelyanov
201c1e64e29SLorenzo Colitti #ifdef CONFIG_INET_DIAG_DESTROY
tcp_diag_destroy(struct sk_buff * in_skb,const struct inet_diag_req_v2 * req)202c1e64e29SLorenzo Colitti static int tcp_diag_destroy(struct sk_buff *in_skb,
203c1e64e29SLorenzo Colitti const struct inet_diag_req_v2 *req)
204c1e64e29SLorenzo Colitti {
205c1e64e29SLorenzo Colitti struct net *net = sock_net(in_skb->sk);
2064461568aSKuniyuki Iwashima struct inet_hashinfo *hinfo;
2074461568aSKuniyuki Iwashima struct sock *sk;
208d7226c7aSDavid Ahern int err;
209c1e64e29SLorenzo Colitti
2104461568aSKuniyuki Iwashima hinfo = net->ipv4.tcp_death_row.hashinfo;
2114461568aSKuniyuki Iwashima sk = inet_diag_find_one_icsk(net, hinfo, req);
2124461568aSKuniyuki Iwashima
213c1e64e29SLorenzo Colitti if (IS_ERR(sk))
214c1e64e29SLorenzo Colitti return PTR_ERR(sk);
215c1e64e29SLorenzo Colitti
216d7226c7aSDavid Ahern err = sock_diag_destroy(sk, ECONNABORTED);
217d7226c7aSDavid Ahern
218d7226c7aSDavid Ahern sock_gen_put(sk);
219d7226c7aSDavid Ahern
220d7226c7aSDavid Ahern return err;
221c1e64e29SLorenzo Colitti }
222c1e64e29SLorenzo Colitti #endif
223c1e64e29SLorenzo Colitti
224a7a0d6a8SEric Dumazet static const struct inet_diag_handler tcp_diag_handler = {
225*db591469SEric Dumazet .owner = THIS_MODULE,
2261942c518SPavel Emelyanov .dump = tcp_diag_dump,
2271942c518SPavel Emelyanov .dump_one = tcp_diag_dump_one,
22817b085eaSArnaldo Carvalho de Melo .idiag_get_info = tcp_diag_get_info,
229c03fa9bcSIvan Delalande .idiag_get_aux = tcp_diag_get_aux,
230c03fa9bcSIvan Delalande .idiag_get_aux_size = tcp_diag_get_aux_size,
231f13c95f0SPavel Emelyanov .idiag_type = IPPROTO_TCP,
2323fd22af8SCraig Gallek .idiag_info_size = sizeof(struct tcp_info),
233c1e64e29SLorenzo Colitti #ifdef CONFIG_INET_DIAG_DESTROY
234c1e64e29SLorenzo Colitti .destroy = tcp_diag_destroy,
235c1e64e29SLorenzo Colitti #endif
23617b085eaSArnaldo Carvalho de Melo };
23717b085eaSArnaldo Carvalho de Melo
tcp_diag_init(void)23817b085eaSArnaldo Carvalho de Melo static int __init tcp_diag_init(void)
23917b085eaSArnaldo Carvalho de Melo {
24017b085eaSArnaldo Carvalho de Melo return inet_diag_register(&tcp_diag_handler);
24117b085eaSArnaldo Carvalho de Melo }
24217b085eaSArnaldo Carvalho de Melo
tcp_diag_exit(void)24317b085eaSArnaldo Carvalho de Melo static void __exit tcp_diag_exit(void)
24417b085eaSArnaldo Carvalho de Melo {
24517b085eaSArnaldo Carvalho de Melo inet_diag_unregister(&tcp_diag_handler);
24617b085eaSArnaldo Carvalho de Melo }
24717b085eaSArnaldo Carvalho de Melo
24817b085eaSArnaldo Carvalho de Melo module_init(tcp_diag_init);
24917b085eaSArnaldo Carvalho de Melo module_exit(tcp_diag_exit);
25017b085eaSArnaldo Carvalho de Melo MODULE_LICENSE("GPL");
251938dbeadSJakub Kicinski MODULE_DESCRIPTION("TCP socket monitoring via SOCK_DIAG");
252aec8dc62SPavel Emelyanov MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-6 /* AF_INET - IPPROTO_TCP */);
253