#include <linux/kernel.h>
#include <linux/net.h>
#include <linux/inet_diag.h>
#include <net/netlink.h>
#include "protocol.h"
static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
struct netlink_callback *cb,
const struct inet_diag_req_v2 *req,
bool net_admin)
{
if (!inet_diag_bc_sk(cb->data, sk))
return 0;
return inet_sk_diag_fill(sk, inet_csk(sk), skb, cb, req, NLM_F_MULTI,
net_admin);
}
static int mptcp_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
struct sk_buff *in_skb = cb->skb;
struct mptcp_sock *msk = NULL;
struct sk_buff *rep;
int err = -ENOENT;
struct net *net;
struct sock *sk;
net = sock_net(in_skb->sk);
msk = mptcp_token_get_sock(net, req->id.idiag_cookie[0]);
if (!msk)
goto out_nosk;
err = -ENOMEM;
sk = (struct sock *)msk;
rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
inet_diag_msg_attrs_size() +
nla_total_size(sizeof(struct mptcp_info)) +
nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
GFP_KERNEL);
if (!rep)
goto out;
err = inet_sk_diag_fill(sk, inet_csk(sk), rep, cb, req, 0,
netlink_net_capable(in_skb, CAP_NET_ADMIN));
if (err < 0) {
WARN_ON(err == -EMSGSIZE);
kfree_skb(rep);
goto out;
}
err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
out:
sock_put(sk);
out_nosk:
return err;
}
struct mptcp_diag_ctx {
long s_slot;
long s_num;
unsigned int l_slot;
unsigned int l_num;
};
static void mptcp_diag_dump_listeners(struct sk_buff *skb, struct netlink_callback *cb,
const struct inet_diag_req_v2 *r,
bool net_admin)
{
struct mptcp_diag_ctx *diag_ctx = (void *)cb->ctx;
struct net *net = sock_net(skb->sk);
struct inet_hashinfo *hinfo;
int i;
hinfo = net->ipv4.tcp_death_row.hashinfo;
for (i = diag_ctx->l_slot; i <= hinfo->lhash2_mask; i++) {
struct inet_listen_hashbucket *ilb;
struct hlist_nulls_node *node;
struct sock *sk;
int num = 0;
ilb = &hinfo->lhash2[i];
rcu_read_lock();
spin_lock(&ilb->lock);
sk_nulls_for_each(sk, node, &ilb->nulls_head) {
const struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(sk);
struct inet_sock *inet = inet_sk(sk);
int ret;
if (num < diag_ctx->l_num)
goto next_listen;
if (!ctx || strcmp(inet_csk(sk)->icsk_ulp_ops->name, "mptcp"))
goto next_listen;
sk = ctx->conn;
if (!sk || !net_eq(sock_net(sk), net))
goto next_listen;
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 (!refcount_inc_not_zero(&sk->sk_refcnt))
goto next_listen;
ret = sk_diag_dump(sk, skb, cb, r, net_admin);
sock_put(sk);
if (ret < 0) {
spin_unlock(&ilb->lock);
rcu_read_unlock();
diag_ctx->l_slot = i;
diag_ctx->l_num = num;
return;
}
diag_ctx->l_num = num + 1;
num = 0;
next_listen:
++num;
}
spin_unlock(&ilb->lock);
rcu_read_unlock();
cond_resched();
diag_ctx->l_num = 0;
}
diag_ctx->l_num = 0;
diag_ctx->l_slot = i;
}
static void mptcp_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 mptcp_diag_ctx *diag_ctx = (void *)cb->ctx;
struct net *net = sock_net(skb->sk);
struct mptcp_sock *msk;
BUILD_BUG_ON(sizeof(cb->ctx) < sizeof(*diag_ctx));
while ((msk = mptcp_token_iter_next(net, &diag_ctx->s_slot,
&diag_ctx->s_num)) != NULL) {
struct inet_sock *inet = (struct inet_sock *)msk;
struct sock *sk = (struct sock *)msk;
int ret = 0;
if (!(r->idiag_states & (1 << sk->sk_state)))
goto next;
if (r->sdiag_family != AF_UNSPEC &&
sk->sk_family != r->sdiag_family)
goto next;
if (r->id.idiag_sport != inet->inet_sport &&
r->id.idiag_sport)
goto next;
if (r->id.idiag_dport != inet->inet_dport &&
r->id.idiag_dport)
goto next;
ret = sk_diag_dump(sk, skb, cb, r, net_admin);
next:
sock_put(sk);
if (ret < 0) {
diag_ctx->s_num--;
break;
}
cond_resched();
}
if ((r->idiag_states & TCPF_LISTEN) && r->id.idiag_dport == 0)
mptcp_diag_dump_listeners(skb, cb, r, net_admin);
}
static void mptcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
void *_info)
{
struct mptcp_sock *msk = mptcp_sk(sk);
struct mptcp_info *info = _info;
r->idiag_rqueue = sk_rmem_alloc_get(sk) +
READ_ONCE(mptcp_sk(sk)->backlog_len);
r->idiag_wqueue = sk_wmem_alloc_get(sk);
if (inet_sk_state_load(sk) == TCP_LISTEN) {
struct sock *lsk = READ_ONCE(msk->first);
if (lsk) {
r->idiag_rqueue = READ_ONCE(lsk->sk_ack_backlog);
r->idiag_wqueue = READ_ONCE(lsk->sk_max_ack_backlog);
}
}
if (!info)
return;
mptcp_diag_fill_info(msk, info);
}
static const struct inet_diag_handler mptcp_diag_handler = {
.owner = THIS_MODULE,
.dump = mptcp_diag_dump,
.dump_one = mptcp_diag_dump_one,
.idiag_get_info = mptcp_diag_get_info,
.idiag_type = IPPROTO_MPTCP,
.idiag_info_size = sizeof(struct mptcp_info),
};
static int __init mptcp_diag_init(void)
{
return inet_diag_register(&mptcp_diag_handler);
}
static void __exit mptcp_diag_exit(void)
{
inet_diag_unregister(&mptcp_diag_handler);
}
module_init(mptcp_diag_init);
module_exit(mptcp_diag_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MPTCP socket monitoring via SOCK_DIAG");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-262 );
