#include <linux/module.h>
#include <linux/net.h>
#include <linux/sock_diag.h>
#include <linux/inet_diag.h>
#include <linux/tcp.h>
#include <net/inet_hashtables.h>
#include <net/inet6_hashtables.h>
#include <net/inet_timewait_sock.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, bool net_admin)
{
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, net_admin);
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);
const struct tcp_ulp_ops *ulp_ops;
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
ulp_ops = icsk->icsk_ulp_ops;
if (ulp_ops) {
err = tcp_diag_put_ulp(skb, sk, ulp_ops, net_admin);
if (err < 0)
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 (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, net_admin);
}
}
return size
+ nla_total_size(sizeof(struct tcp_info))
+ nla_total_size(sizeof(struct inet_diag_msg))
+ inet_diag_msg_attrs_size()
+ nla_total_size(sizeof(struct inet_diag_meminfo))
+ nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
+ nla_total_size(TCP_CA_NAME_MAX)
+ nla_total_size(sizeof(struct tcpvegas_info))
+ 64;
}
static int tcp_twsk_diag_fill(struct sock *sk,
struct sk_buff *skb,
struct netlink_callback *cb,
u16 nlmsg_flags, bool net_admin)
{
struct inet_timewait_sock *tw = inet_twsk(sk);
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
long tmo;
nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, cb->nlh->nlmsg_type,
sizeof(*r), nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
r = nlmsg_data(nlh);
DEBUG_NET_WARN_ON_ONCE(tw->tw_state != TCP_TIME_WAIT);
inet_diag_msg_common_fill(r, sk);
r->idiag_retrans = 0;
r->idiag_state = READ_ONCE(tw->tw_substate);
r->idiag_timer = 3;
tmo = tw->tw_timer.expires - jiffies;
r->idiag_expires = jiffies_delta_to_msecs(tmo);
r->idiag_rqueue = 0;
r->idiag_wqueue = 0;
r->idiag_uid = 0;
r->idiag_inode = 0;
if (net_admin && nla_put_u32(skb, INET_DIAG_MARK,
tw->tw_mark)) {
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
nlmsg_end(skb, nlh);
return 0;
}
static int tcp_req_diag_fill(struct sock *sk, struct sk_buff *skb,
struct netlink_callback *cb,
u16 nlmsg_flags, bool net_admin)
{
struct request_sock *reqsk = inet_reqsk(sk);
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
long tmo;
nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
r = nlmsg_data(nlh);
inet_diag_msg_common_fill(r, sk);
r->idiag_state = TCP_SYN_RECV;
r->idiag_timer = 1;
r->idiag_retrans = READ_ONCE(reqsk->num_retrans);
BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
offsetof(struct sock, sk_cookie));
tmo = READ_ONCE(inet_reqsk(sk)->rsk_timer.expires) - jiffies;
r->idiag_expires = jiffies_delta_to_msecs(tmo);
r->idiag_rqueue = 0;
r->idiag_wqueue = 0;
r->idiag_uid = 0;
r->idiag_inode = 0;
if (net_admin && nla_put_u32(skb, INET_DIAG_MARK,
inet_rsk(reqsk)->ir_mark)) {
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
nlmsg_end(skb, nlh);
return 0;
}
static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
struct netlink_callback *cb,
const struct inet_diag_req_v2 *r,
u16 nlmsg_flags, bool net_admin)
{
if (sk->sk_state == TCP_TIME_WAIT)
return tcp_twsk_diag_fill(sk, skb, cb, nlmsg_flags, net_admin);
if (sk->sk_state == TCP_NEW_SYN_RECV)
return tcp_req_diag_fill(sk, skb, cb, nlmsg_flags, net_admin);
return inet_sk_diag_fill(sk, inet_csk(sk), skb, cb, r, nlmsg_flags,
net_admin);
}
static void twsk_build_assert(void)
{
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_family) !=
offsetof(struct sock, sk_family));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_num) !=
offsetof(struct inet_sock, inet_num));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_dport) !=
offsetof(struct inet_sock, inet_dport));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_rcv_saddr) !=
offsetof(struct inet_sock, inet_rcv_saddr));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_daddr) !=
offsetof(struct inet_sock, inet_daddr));
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_rcv_saddr) !=
offsetof(struct sock, sk_v6_rcv_saddr));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_daddr) !=
offsetof(struct sock, sk_v6_daddr));
#endif
}
static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
const struct inet_diag_req_v2 *r)
{
bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
struct inet_diag_dump_data *cb_data = cb->data;
struct net *net = sock_net(skb->sk);
u32 idiag_states = r->idiag_states;
struct inet_hashinfo *hashinfo;
int i, num, s_i, s_num;
struct sock *sk;
hashinfo = net->ipv4.tcp_death_row.hashinfo;
if (idiag_states & TCPF_SYN_RECV)
idiag_states |= TCPF_NEW_SYN_RECV;
s_i = cb->args[1];
s_num = num = cb->args[2];
if (cb->args[0] == 0) {
if (!(idiag_states & TCPF_LISTEN) || r->id.idiag_dport)
goto skip_listen_ht;
for (i = s_i; i <= hashinfo->lhash2_mask; i++) {
struct inet_listen_hashbucket *ilb;
struct hlist_nulls_node *node;
num = 0;
ilb = &hashinfo->lhash2[i];
if (hlist_nulls_empty(&ilb->nulls_head)) {
s_num = 0;
continue;
}
spin_lock(&ilb->lock);
sk_nulls_for_each(sk, node, &ilb->nulls_head) {
struct inet_sock *inet = inet_sk(sk);
if (!net_eq(sock_net(sk), net))
continue;
if (num < s_num) {
num++;
continue;
}
if (r->sdiag_family != AF_UNSPEC &&
sk->sk_family != r->sdiag_family)
goto next_listen;
if (r->id.idiag_sport != inet->inet_sport &&
r->id.idiag_sport)
goto next_listen;
if (!inet_diag_bc_sk(cb_data, sk))
goto next_listen;
if (inet_sk_diag_fill(sk, inet_csk(sk), skb,
cb, r, NLM_F_MULTI,
net_admin) < 0) {
spin_unlock(&ilb->lock);
goto done;
}
next_listen:
++num;
}
spin_unlock(&ilb->lock);
s_num = 0;
}
skip_listen_ht:
cb->args[0] = 1;
s_i = num = s_num = 0;
}
#define SKARR_SZ 16
if (cb->args[0] == 1) {
if (!(idiag_states & TCPF_BOUND_INACTIVE))
goto skip_bind_ht;
for (i = s_i; i < hashinfo->bhash_size; i++) {
struct inet_bind_hashbucket *ibb;
struct inet_bind2_bucket *tb2;
struct sock *sk_arr[SKARR_SZ];
int num_arr[SKARR_SZ];
int idx, accum, res;
resume_bind_walk:
num = 0;
accum = 0;
ibb = &hashinfo->bhash2[i];
if (hlist_empty(&ibb->chain)) {
s_num = 0;
continue;
}
spin_lock_bh(&ibb->lock);
inet_bind_bucket_for_each(tb2, &ibb->chain) {
if (!net_eq(ib2_net(tb2), net))
continue;
sk_for_each_bound(sk, &tb2->owners) {
struct inet_sock *inet = inet_sk(sk);
if (num < s_num)
goto next_bind;
if (sk->sk_state != TCP_CLOSE ||
!inet->inet_num)
goto next_bind;
if (r->sdiag_family != AF_UNSPEC &&
r->sdiag_family != sk->sk_family)
goto next_bind;
if (!inet_diag_bc_sk(cb_data, sk))
goto next_bind;
sock_hold(sk);
num_arr[accum] = num;
sk_arr[accum] = sk;
if (++accum == SKARR_SZ)
goto pause_bind_walk;
next_bind:
num++;
}
}
pause_bind_walk:
spin_unlock_bh(&ibb->lock);
res = 0;
for (idx = 0; idx < accum; idx++) {
if (res >= 0) {
res = inet_sk_diag_fill(sk_arr[idx],
NULL, skb, cb,
r, NLM_F_MULTI,
net_admin);
if (res < 0)
num = num_arr[idx];
}
sock_put(sk_arr[idx]);
}
if (res < 0)
goto done;
cond_resched();
if (accum == SKARR_SZ) {
s_num = num + 1;
goto resume_bind_walk;
}
s_num = 0;
}
skip_bind_ht:
cb->args[0] = 2;
s_i = num = s_num = 0;
}
if (!(idiag_states & ~TCPF_LISTEN))
goto out;
for (i = s_i; i <= hashinfo->ehash_mask; i++) {
struct inet_ehash_bucket *head = &hashinfo->ehash[i];
spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
struct hlist_nulls_node *node;
struct sock *sk_arr[SKARR_SZ];
int num_arr[SKARR_SZ];
int idx, accum, res;
if (hlist_nulls_empty(&head->chain))
continue;
if (i > s_i)
s_num = 0;
next_chunk:
num = 0;
accum = 0;
spin_lock_bh(lock);
sk_nulls_for_each(sk, node, &head->chain) {
int state;
if (!net_eq(sock_net(sk), net))
continue;
if (num < s_num)
goto next_normal;
state = (sk->sk_state == TCP_TIME_WAIT) ?
READ_ONCE(inet_twsk(sk)->tw_substate) : sk->sk_state;
if (!(idiag_states & (1 << state)))
goto next_normal;
if (r->sdiag_family != AF_UNSPEC &&
sk->sk_family != r->sdiag_family)
goto next_normal;
if (r->id.idiag_sport != htons(READ_ONCE(sk->sk_num)) &&
r->id.idiag_sport)
goto next_normal;
if (r->id.idiag_dport != sk->sk_dport &&
r->id.idiag_dport)
goto next_normal;
twsk_build_assert();
if (!inet_diag_bc_sk(cb_data, sk))
goto next_normal;
if (!refcount_inc_not_zero(&sk->sk_refcnt))
goto next_normal;
num_arr[accum] = num;
sk_arr[accum] = sk;
if (++accum == SKARR_SZ)
break;
next_normal:
++num;
}
spin_unlock_bh(lock);
res = 0;
for (idx = 0; idx < accum; idx++) {
if (res >= 0) {
res = sk_diag_fill(sk_arr[idx], skb, cb, r,
NLM_F_MULTI, net_admin);
if (res < 0)
num = num_arr[idx];
}
sock_gen_put(sk_arr[idx]);
}
if (res < 0)
break;
cond_resched();
if (accum == SKARR_SZ) {
s_num = num + 1;
goto next_chunk;
}
}
done:
cb->args[1] = i;
cb->args[2] = num;
out:
;
}
static struct sock *tcp_diag_find_one_icsk(struct net *net,
const struct inet_diag_req_v2 *req)
{
struct sock *sk;
rcu_read_lock();
if (req->sdiag_family == AF_INET) {
sk = inet_lookup(net, NULL, 0, req->id.idiag_dst[0],
req->id.idiag_dport, req->id.idiag_src[0],
req->id.idiag_sport, req->id.idiag_if);
#if IS_ENABLED(CONFIG_IPV6)
} else if (req->sdiag_family == AF_INET6) {
if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
sk = inet_lookup(net, NULL, 0, req->id.idiag_dst[3],
req->id.idiag_dport, req->id.idiag_src[3],
req->id.idiag_sport, req->id.idiag_if);
else
sk = inet6_lookup(net, NULL, 0,
(struct in6_addr *)req->id.idiag_dst,
req->id.idiag_dport,
(struct in6_addr *)req->id.idiag_src,
req->id.idiag_sport,
req->id.idiag_if);
#endif
} else {
rcu_read_unlock();
return ERR_PTR(-EINVAL);
}
rcu_read_unlock();
if (!sk)
return ERR_PTR(-ENOENT);
if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
sock_gen_put(sk);
return ERR_PTR(-ENOENT);
}
return sk;
}
static int tcp_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
struct sk_buff *in_skb = cb->skb;
struct sk_buff *rep;
struct sock *sk;
struct net *net;
bool net_admin;
int err;
net = sock_net(in_skb->sk);
sk = tcp_diag_find_one_icsk(net, req);
if (IS_ERR(sk))
return PTR_ERR(sk);
net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN);
rep = nlmsg_new(tcp_diag_get_aux_size(sk, net_admin), GFP_KERNEL);
if (!rep) {
err = -ENOMEM;
goto out;
}
err = sk_diag_fill(sk, rep, cb, req, 0, net_admin);
if (err < 0) {
WARN_ON(err == -EMSGSIZE);
nlmsg_free(rep);
goto out;
}
err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
out:
if (sk)
sock_gen_put(sk);
return err;
}
#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;
int err;
sk = tcp_diag_find_one_icsk(net, 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 = {
.owner = THIS_MODULE,
.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_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 );
