diff options
Diffstat (limited to 'net/ipv4/tcp_diag.c')
| -rw-r--r-- | net/ipv4/tcp_diag.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c new file mode 100644 index 000000000..75a1c985f --- /dev/null +++ b/net/ipv4/tcp_diag.c @@ -0,0 +1,238 @@ +// 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) +{ + inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r); +} + +static int tcp_diag_dump_one(struct netlink_callback *cb, + const struct inet_diag_req_v2 *req) +{ + return inet_diag_dump_one_icsk(&tcp_hashinfo, 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 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 */); |