/*
* net/dccp/proto.c
*
* An implementation of the DCCP protocol
* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/dccp.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/in.h>
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <net/checksum.h>
#include <net/inet_sock.h>
#include <net/sock.h>
#include <net/xfrm.h>
#include <asm/ioctls.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include "ccid.h"
#include "dccp.h"
#include "feat.h"
DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
EXPORT_SYMBOL_GPL(dccp_statistics);
struct percpu_counter dccp_orphan_count;
EXPORT_SYMBOL_GPL(dccp_orphan_count);
struct inet_hashinfo dccp_hashinfo;
EXPORT_SYMBOL_GPL(dccp_hashinfo);
/* the maximum queue length for tx in packets. 0 is no limit */
int sysctl_dccp_tx_qlen __read_mostly = 5;
void dccp_set_state(struct sock *sk, const int state)
{
const int oldstate = sk->sk_state;
dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk,
dccp_state_name(oldstate), dccp_state_name(state));
WARN_ON(state == oldstate);
switch (state) {
case DCCP_OPEN:
if (oldstate != DCCP_OPEN)
DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
/* Client retransmits all Confirm options until entering OPEN */
if (oldstate == DCCP_PARTOPEN)
dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg);
break;
case DCCP_CLOSED:
if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ ||
oldstate == DCCP_CLOSING)
DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
sk->sk_prot->unhash(sk);
if (inet_csk(sk)->icsk_bind_hash != NULL &&
!(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
inet_put_port(sk);
/* fall through */
default:
if (oldstate == DCCP_OPEN)
DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
}
/* Change state AFTER socket is unhashed to avoid closed
* socket sitting in hash tables.
*/
sk->sk_state = state;
}
EXPORT_SYMBOL_GPL(dccp_set_state);
static void dccp_finish_passive_close(struct sock *sk)
{
switch (sk->sk_state) {
case DCCP_PASSIVE_CLOSE:
/* Node (client or server) has received Close packet. */
dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
dccp_set_state(sk, DCCP_CLOSED);
break;
case DCCP_PASSIVE_CLOSEREQ:
/*
* Client received CloseReq. We set the `active' flag so that
* dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
*/
dccp_send_close(sk, 1);
dccp_set_state(sk, DCCP_CLOSING);
}
}
void dccp_done(struct sock *sk)
{
dccp_set_state(sk, DCCP_CLOSED);
dccp_clear_xmit_timers(sk);
sk->sk_shutdown = SHUTDOWN_MASK;
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_state_change(sk);
else
inet_csk_destroy_sock(sk);
}
EXPORT_SYMBOL_GPL(dccp_done);
const char *dccp_packet_name(const int type)
{
static const char *const dccp_packet_names[] = {
[DCCP_PKT_REQUEST] = "REQUEST",
[DCCP_PKT_RESPONSE] = "RESPONSE",
[DCCP_PKT_DATA]