path: root/net/ipv4/inet_diag.c

/*
 * inet_diag.c	Module for monitoring INET transport protocols sockets.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/cache.h>
#include <linux/init.h>
#include <linux/time.h>

#include <net/icmp.h>
#include <net/tcp.h>
#include <net/ipv6.h>
#include <net/inet_common.h>
#include <net/inet_connection_sock.h>
#include <net/inet_hashtables.h>
#include <net/inet_timewait_sock.h>
#include <net/inet6_hashtables.h>
#include <net/netlink.h>

#include <linux/inet.h>
#include <linux/stddef.h>

#include <linux/inet_diag.h>

static const struct inet_diag_handler **inet_diag_table;

struct inet_diag_entry {
	__be32 *saddr;
	__be32 *daddr;
	u16 sport;
	u16 dport;
	u16 family;
	u16 userlocks;
};

static struct sock *idiagnl;

#define INET_DIAG_PUT(skb, attrtype, attrlen) \
	RTA_DATA(__RTA_PUT(skb, attrtype, attrlen))

static DEFINE_MUTEX(inet_diag_table_mutex);

static const struct inet_diag_handler *inet_diag_lock_handler(int type)
{
	if (!inet_diag_table[type])
		request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
			       NETLINK_INET_DIAG, type);

	mutex_lock(&inet_diag_table_mutex);
	if (!inet_diag_table[type])
		return ERR_PTR(-ENOENT);

	return inet_diag_table[type];
}

static inline void inet_diag_unlock_handler(
	const struct inet_diag_handler *handler)
{
	mutex_unlock(&inet_diag_table_mutex);
}

static int inet_csk_diag_fill(struct sock *sk,
			      struct sk_buff *skb,
			      int ext, u32 pid, u32 seq, u16 nlmsg_flags,
			      const struct nlmsghdr *unlh)
{
	const struct inet_sock *inet = inet_sk(sk);
	const struct inet_connection_sock *icsk = inet_csk(sk);
	struct inet_diag_msg *r;
	struct nlmsghdr  *nlh;
	void *info = NULL;
	struct inet_diag_meminfo  *minfo = NULL;
	unsigned char	 *b = skb_tail_pointer(skb);
	const struct inet_diag_handler *handler;

	handler = inet_diag_table[unlh->nlmsg_type];
	BUG_ON(handler == NULL);

	nlh = NLMSG_PUT(skb, pid, seq, unlh->nlmsg_type, sizeof(*r));
	nlh->nlmsg_flags = nlmsg_flags;

	r = NLMSG_DATA(nlh);
	BUG_ON(sk->sk_state == TCP_TIME_WAIT);

	if (ext & (1 << (INET_DIAG_MEMINFO - 1)))
		minfo = INET_DIAG_PUT(skb, INET_DIAG_MEMINFO, sizeof(*minfo));

	if (ext & (1 << (INET_DIAG_INFO - 1)))
		info = INET_DIAG_PUT(skb, INET_DIAG_INFO,
				     handler->idiag_info_size);

	if ((ext & (1 << (INET_DIAG_CONG - 1))) && icsk->icsk_ca_ops) {
		const size_t len = strlen(icsk->icsk_ca_ops->name);

		strcpy(INET_DIAG_PUT(skb, INET_DIAG_CONG, len + 1),
		       icsk->icsk_ca_ops->name);
	}

	r->idiag_family = sk->sk_family;
	r->idiag_state = sk->sk_state;
	r->idiag_timer = 0;
	r->idiag_retrans = 0;

	r->id.idiag_if = sk->sk_bound_dev_if;
	r->id.idiag_cookie[0] = (u32)(unsigned long)sk;
	r->id.idiag_cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1);

	r->id.idiag_sport = inet->inet_sport;
	r->id.idiag_dport = inet->inet_dport;
	r->id.idiag_src[0] = inet->inet_rcv_saddr;
	r->id.idiag_dst[0] = inet->inet_daddr;

#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
	if (r->idiag_family == AF_INET6) {
		struct ipv6_pinfo *np = inet6_sk(sk);

		ipv6_addr_copy((struct in6_addr *)r->id.idiag_src,
			       &np->rcv_saddr);
		ipv6_addr_copy((struct in6_addr *)r->id.idiag_dst,
			       &np->daddr);
	}
#endif

#define EXPIRES_IN_MS(tmo)  DIV_ROUND_UP((tmo - jiffies) * 1000, HZ)

	if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
		r->idiag_timer = 1;
		r->idiag_retrans = icsk->icsk_retransmits;
		r->idiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
	} else if (icsk->icsk_pending