[mirror_ubuntu-bionic-kernel.git] / net / dccp / dccp.h

#ifndef _DCCP_H
#define _DCCP_H
/*
 *  net/dccp/dccp.h
 *
 *  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/config.h>
#include <linux/dccp.h>
#include <net/snmp.h>
#include <net/sock.h>
#include <net/tcp.h>

#ifdef CONFIG_IP_DCCP_DEBUG
extern int dccp_debug;

#define dccp_pr_debug(format, a...) \
	do { if (dccp_debug) \
		printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \
	} while (0)
#define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) \
					     printk(format, ##a); } while (0)
#else
#define dccp_pr_debug(format, a...)
#define dccp_pr_debug_cat(format, a...)
#endif

extern struct inet_hashinfo dccp_hashinfo;

extern atomic_t dccp_orphan_count;
extern int dccp_tw_count;
extern void dccp_tw_deschedule(struct inet_timewait_sock *tw);

extern void dccp_time_wait(struct sock *sk, int state, int timeo);

/* FIXME: Right size this */
#define DCCP_MAX_OPT_LEN 128

#define DCCP_MAX_PACKET_HDR 32

#define MAX_DCCP_HEADER  (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER)

#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
				     * state, about 60 seconds */

/* draft-ietf-dccp-spec-11.txt initial RTO value */
#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))

/* Maximal interval between probes for local resources.  */
#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))

#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */

extern struct proto dccp_v4_prot;

/* is seq1 < seq2 ? */
static inline int before48(const u64 seq1, const u64 seq2)
{
	return (s64)((seq1 << 16) - (seq2 << 16)) < 0;
}

/* is seq1 > seq2 ? */
static inline int after48(const u64 seq1, const u64 seq2)
{
	return (s64)((seq2 << 16) - (seq1 << 16)) < 0;
}

/* is seq2 <= seq1 <= seq3 ? */
static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3)
{
	return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16);
}

static inline u64 max48(const u64 seq1, const u64 seq2)
{
	return after48(seq1, seq2) ? seq1 : seq2;
}

enum {
	DCCP_MIB_NUM = 0,
	DCCP_MIB_ACTIVEOPENS,			/* ActiveOpens */
	DCCP_MIB_ESTABRESETS,			/* EstabResets */
	DCCP_MIB_CURRESTAB,			/* CurrEstab */
	DCCP_MIB_OUTSEGS,			/* OutSegs */ 
	DCCP_MIB_OUTRSTS,
	DCCP_MIB_ABORTONTIMEOUT,
	DCCP_MIB_TIMEOUTS,
	DCCP_MIB_ABORTFAILED,
	DCCP_MIB_PASSIVEOPENS,
	DCCP_MIB_ATTEMPTFAILS,
	DCCP_MIB_OUTDATAGRAMS,
	DCCP_MIB_INERRS,
	DCCP_MIB_OPTMANDATORYERROR,
	DCCP_MIB_INVALIDOPT,
	__DCCP_MIB_MAX
};

#define DCCP_MIB_MAX	__DCCP_MIB_MAX
struct dccp_mib {
	unsigned long	mibs[DCCP_MIB_MAX];
} __SNMP_MIB_ALIGN__;

DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics);
#define DCCP_INC_STATS(field)	    SNMP_INC_STATS(dccp_statistics, field)
#define DCCP_INC_STATS_BH(field)    SNMP_INC_STATS_BH(dccp_statistics, field)
#define DCCP_INC_STATS_USER(field)  SNMP_INC_STATS_USER(dccp_statistics, field)
#define DCCP_DEC_STATS(field)	    SNMP_DEC_STATS(dccp_statistics, field)
#define DCCP_ADD_STATS_BH(field, val) \
			SNMP_ADD_STATS_BH(dccp_statistics, field, val)
#define DCCP_ADD_STATS_USER(field, val)	\
			SNMP_ADD_STATS_USER(dccp_statistics, field, val)

extern int  dccp_transmit_skb(struct sock *sk, struct sk_buff *skb);
extern int  dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb);

extern int dccp_send_response(struct sock *sk);
extern void dccp_send_ack(struct sock *sk);
extern void dccp_send_delayed_ack(struct sock *sk);
extern void dccp_send_sync(struct sock *sk, const u64 seq,
			   const enum dccp_pkt_type pkt_type);

extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb,
			   const int len);

extern void dccp_init_xmit_timers(struct sock *sk);
static inline void dccp_clear_xmit_timers(struct sock *sk)
{
	inet_csk_clear_xmit_timers(sk);
}

extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu);

extern const char *dccp_packet_name(const int type);
extern const char *dccp_state_name(const int state);

static inline void dccp_set_state(struct sock *sk, const int state)
{
	const int oldstate = sk->sk_state;

	dccp_pr_debug("%s(%p) %-10.10s -> %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);
		break;

	case DCCP_CLOSED:
		if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN)
			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(&dccp_hashinfo, 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;
}

static inline 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);
}

static inline void dccp_openreq_init(struct request_sock *req,
				     struct dccp_sock *dp,
				     struct sk_buff *skb)
{
	/*
	 * FIXME: fill in the other req fields from the DCCP options
	 * received
	 */
	inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
	inet_rsk(req)->acked	= 0;
	req->rcv_wnd = 0;
}

extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb);

extern struct sock *dccp_create_openreq_child(struct sock *sk,
					      const struct request_sock *req,
					      const struct sk_buff *skb);

extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb);

extern void dccp_v4_err(struct sk_buff *skb, u32);

extern int dccp_v4_rcv(struct sk_buff *skb);

extern struct sock *dccp_v4_request_recv_sock(struct sock *sk,
					      struct sk_buff *skb,
					      struct request_sock *req,
					      struct dst_entry *dst);
extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
				   struct request_sock *req,
				   struct request_sock **prev);

extern int dccp_child_process(struct sock *parent, struct sock *child,
			      struct sk_buff *skb);
extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
				  struct dccp_hdr *dh, unsigned len);
extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
				const struct dccp_hdr *dh, const unsigned len);

extern void		dccp_close(struct sock *sk, long timeout);
extern struct sk_buff	*dccp_make_response(struct sock *sk,
					    struct dst_entry *dst,
					    struct request_sock *req);
extern struct sk_buff	*dccp_make_reset(struct sock *sk,
					 struct dst_entry *dst,
					 enum dccp_reset_codes code);

extern int	   dccp_connect(struct sock *sk);
extern int	   dccp_disconnect(struct sock *sk, int flags);
extern int	   dccp_getsockopt(struct sock *sk, int level, int optname,
				   char __user *optval, int __user *optlen);
extern int	   dccp_setsockopt(struct sock *sk, int level, int optname,
				   char __user *optval, int optlen);
extern int	   dccp_ioctl(struct sock *sk, int cmd, unsigned long arg);
extern int	   dccp_sendmsg(struct kiocb *iocb, struct sock *sk,
				struct msghdr *msg, size_t size);
extern int	   dccp_recvmsg(struct kiocb *iocb, struct sock *sk,
				struct msghdr *msg, size_t len, int nonblock,
				int flags, int *addr_len);
extern void	   dccp_shutdown(struct sock *sk, int how);

extern int	   dccp_v4_checksum(const struct sk_buff *skb,
				    const u32 saddr, const u32 daddr);

extern int	   dccp_v4_send_reset(struct sock *sk,
				      enum dccp_reset_codes code);
extern void	   dccp_send_close(struct sock *sk);

struct dccp_skb_cb {
	__u8 dccpd_type;
	__u8 dccpd_reset_code;
	__u8 dccpd_service;
	__u8 dccpd_ccval;
	__u64 dccpd_seq;
	__u64 dccpd_ack_seq;
	int  dccpd_opt_len;
};

#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))

static inline int dccp_non_data_packet(const struct sk_buff *skb)
{
	const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;

	return type == DCCP_PKT_ACK	 ||
	       type == DCCP_PKT_CLOSE	 ||
	       type == DCCP_PKT_CLOSEREQ ||
	       type == DCCP_PKT_RESET	 ||
	       type == DCCP_PKT_SYNC	 ||
	       type == DCCP_PKT_SYNCACK;
}

static inline int dccp_packet_without_ack(const struct sk_buff *skb)
{
	const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;

	return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST;
}

#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)

static inline void dccp_set_seqno(u64 *seqno, u64 value)
{
	if (value > DCCP_MAX_SEQNO)
		value -= DCCP_MAX_SEQNO + 1;
	*seqno = value;
}

static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
{
	return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
}

static inline void dccp_inc_seqno(u64 *seqno)
{
	if (++*seqno > DCCP_MAX_SEQNO)
		*seqno = 0;
}

static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
{
	struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh +
							   sizeof(*dh));

#if defined(__LITTLE_ENDIAN_BITFIELD)
	dh->dccph_seq	   = htonl((gss >> 32)) >> 8;
#elif defined(__BIG_ENDIAN_BITFIELD)
	dh->dccph_seq	   = htonl((gss >> 32));
#else
#error  "Adjust your <asm/byteorder.h> defines"
#endif
	dhx->dccph_seq_low = htonl(gss & 0xffffffff);
}

static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack,
				    const u64 gsr)
{
#if defined(__LITTLE_ENDIAN_BITFIELD)
	dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8;
#elif defined(__BIG_ENDIAN_BITFIELD)
	dhack->dccph_ack_nr_high = htonl((gsr >> 32));
#else
#error  "Adjust your <asm/byteorder.h> defines"
#endif
	dhack->dccph_ack_nr_low  = htonl(gsr & 0xffffffff);
}

static inline void dccp_update_gsr(struct sock *sk, u64 seq)
{
	struct dccp_sock *dp = dccp_sk(sk);
	u64 tmp_gsr;

	dccp_set_seqno(&tmp_gsr,
		       (dp->dccps_gsr + 1 -
		        (dp->dccps_options.dccpo_sequence_window / 4)));
	dp->dccps_gsr = seq;
	dccp_set_seqno(&dp->dccps_swl, max48(tmp_gsr, dp->dccps_isr));
	dccp_set_seqno(&dp->dccps_swh,
		       (dp->dccps_gsr +
			(3 * dp->dccps_options.dccpo_sequence_window) / 4));
}

static inline void dccp_update_gss(struct sock *sk, u64 seq)
{
	struct dccp_sock *dp = dccp_sk(sk);
	u64 tmp_gss;

	dccp_set_seqno(&tmp_gss,
		       (dp->dccps_gss -
			dp->dccps_options.dccpo_sequence_window + 1));
	dp->dccps_awl = max48(tmp_gss, dp->dccps_iss);
	dp->dccps_awh = dp->dccps_gss = seq;
}

extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb);
extern void dccp_insert_option_elapsed_time(struct sock *sk,
					    struct sk_buff *skb,
					    u32 elapsed_time);
extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
			       unsigned char option,
			       const void *value, unsigned char len);

extern struct socket *dccp_ctl_socket;

#define DCCP_ACKPKTS_STATE_RECEIVED	0
#define DCCP_ACKPKTS_STATE_ECN_MARKED	(1 << 6)
#define DCCP_ACKPKTS_STATE_NOT_RECEIVED	(3 << 6)

#define DCCP_ACKPKTS_STATE_MASK		0xC0 /* 11000000 */
#define DCCP_ACKPKTS_LEN_MASK		0x3F /* 00111111 */

/** struct dccp_ackpkts - acknowledgeable packets
 *
 * This data structure is the one defined in the DCCP draft
 * Appendix A.
 *
 * @dccpap_buf_head - circular buffer head
 * @dccpap_buf_tail - circular buffer tail
 * @dccpap_buf_ackno - ack # of the most recent packet acknowledgeable in the
 * 		       buffer (i.e. %dccpap_buf_head)
 * @dccpap_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
 * 		       by the buffer with State 0
 *
 * Additionally, the HC-Receiver must keep some information about the
 * Ack Vectors it has recently sent. For each packet sent carrying an
 * Ack Vector, it remembers four variables:
 *
 * @dccpap_ack_seqno - the Sequence Number used for the packet
 * 		       (HC-Receiver seqno)
 * @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
 * @dccpap_ack_ackno - the Acknowledgement Number used for the packet
 * 		       (HC-Sender seqno)
 * @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
 *
 * @dccpap_buf_len - circular buffer length
 * @dccpap_buf - circular buffer of acknowledgeable packets
 */
struct dccp_ackpkts {
	unsigned int		dccpap_buf_head;
	unsigned int		dccpap_buf_tail;
	u64			dccpap_buf_ackno;
	u64			dccpap_ack_seqno;
	u64			dccpap_ack_ackno;
	unsigned int		dccpap_ack_ptr;
	unsigned int		dccpap_buf_vector_len;
	unsigned int		dccpap_ack_vector_len;
	unsigned int		dccpap_buf_len;
	unsigned long           dccpap_time;
	u8			dccpap_buf_nonce;
	u8			dccpap_ack_nonce;
	u8			dccpap_buf[0];
};

extern struct dccp_ackpkts *
		dccp_ackpkts_alloc(unsigned int len,
				  const unsigned int __nocast priority);
extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, u64 ackno, u8 state);
extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
					 struct sock *sk, u64 ackno);

#ifdef CONFIG_IP_DCCP_DEBUG
extern void dccp_ackvector_print(const u64 ackno,
				 const unsigned char *vector, int len);
extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
#else
static inline void dccp_ackvector_print(const u64 ackno,
					const unsigned char *vector,
					int len) { }
static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
#endif

#endif /* _DCCP_H */
Commit	Line	Data
7c657876 ACM	1	#ifndef _DCCP_H
	2	#define _DCCP_H
	3	/*
	4	* net/dccp/dccp.h
	5	*
	6	* An implementation of the DCCP protocol
	7	* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*/
	13
725ba8ee	14	#include <linux/config.h>
7c657876 ACM	15	#include <linux/dccp.h>
	16	#include <net/snmp.h>
	17	#include <net/sock.h>
	18	#include <net/tcp.h>
	19
725ba8ee	20	#ifdef CONFIG_IP_DCCP_DEBUG
7c657876 ACM	21	extern int dccp_debug;
	22
	23	#define dccp_pr_debug(format, a...) \
	24	do { if (dccp_debug) \
	25	printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \
	26	} while (0)
7690af3f ACM	27	#define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) \
7690af3f ACM	28	printk(format, ##a); } while (0)
7c657876 ACM	29	#else
	30	#define dccp_pr_debug(format, a...)
	31	#define dccp_pr_debug_cat(format, a...)
	32	#endif
	33
	34	extern struct inet_hashinfo dccp_hashinfo;
	35
	36	extern atomic_t dccp_orphan_count;
	37	extern int dccp_tw_count;
	38	extern void dccp_tw_deschedule(struct inet_timewait_sock *tw);
	39
	40	extern void dccp_time_wait(struct sock *sk, int state, int timeo);
	41
	42	/* FIXME: Right size this */
	43	#define DCCP_MAX_OPT_LEN 128
	44
	45	#define DCCP_MAX_PACKET_HDR 32
	46
	47	#define MAX_DCCP_HEADER (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER)
	48
	49	#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
	50	* state, about 60 seconds */
	51
	52	/* draft-ietf-dccp-spec-11.txt initial RTO value */
	53	#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))
	54
	55	/* Maximal interval between probes for local resources. */
	56	#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))
	57
	58	#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */
	59
	60	extern struct proto dccp_v4_prot;
	61
	62	/* is seq1 < seq2 ? */
a10cedd4	63	static inline int before48(const u64 seq1, const u64 seq2)
7c657876	64	{
a10cedd4	65	return (s64)((seq1 << 16) - (seq2 << 16)) < 0;
7c657876 ACM	66	}
	67
	68	/* is seq1 > seq2 ? */
a10cedd4	69	static inline int after48(const u64 seq1, const u64 seq2)
7c657876	70	{
a10cedd4	71	return (s64)((seq2 << 16) - (seq1 << 16)) < 0;
7c657876 ACM	72	}
	73
	74	/* is seq2 <= seq1 <= seq3 ? */
a10cedd4	75	static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3)
7c657876 ACM	76	{
	77	return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16);
	78	}
	79
	80	static inline u64 max48(const u64 seq1, const u64 seq2)
	81	{
	82	return after48(seq1, seq2) ? seq1 : seq2;
	83	}
	84
	85	enum {
	86	DCCP_MIB_NUM = 0,
	87	DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */
	88	DCCP_MIB_ESTABRESETS, /* EstabResets */
	89	DCCP_MIB_CURRESTAB, /* CurrEstab */
	90	DCCP_MIB_OUTSEGS, /* OutSegs */
	91	DCCP_MIB_OUTRSTS,
	92	DCCP_MIB_ABORTONTIMEOUT,
	93	DCCP_MIB_TIMEOUTS,
	94	DCCP_MIB_ABORTFAILED,
	95	DCCP_MIB_PASSIVEOPENS,
	96	DCCP_MIB_ATTEMPTFAILS,
	97	DCCP_MIB_OUTDATAGRAMS,
	98	DCCP_MIB_INERRS,
	99	DCCP_MIB_OPTMANDATORYERROR,
	100	DCCP_MIB_INVALIDOPT,
	101	__DCCP_MIB_MAX
	102	};
	103
	104	#define DCCP_MIB_MAX __DCCP_MIB_MAX
	105	struct dccp_mib {
	106	unsigned long mibs[DCCP_MIB_MAX];
	107	} __SNMP_MIB_ALIGN__;
	108
	109	DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics);
7690af3f ACM	110	#define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field)
	111	#define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field)
	112	#define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field)
	113	#define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field)
	114	#define DCCP_ADD_STATS_BH(field, val) \
	115	SNMP_ADD_STATS_BH(dccp_statistics, field, val)
	116	#define DCCP_ADD_STATS_USER(field, val) \
	117	SNMP_ADD_STATS_USER(dccp_statistics, field, val)
7c657876 ACM	118
	119	extern int dccp_transmit_skb(struct sock sk, struct sk_buff skb);
	120	extern int dccp_retransmit_skb(struct sock sk, struct sk_buff skb);
	121
	122	extern int dccp_send_response(struct sock *sk);
	123	extern void dccp_send_ack(struct sock *sk);
	124	extern void dccp_send_delayed_ack(struct sock *sk);
e92ae93a ACM	125	extern void dccp_send_sync(struct sock *sk, const u64 seq,
e92ae93a ACM	126	const enum dccp_pkt_type pkt_type);
7c657876	127
27258ee5 ACM	128	extern int dccp_write_xmit(struct sock sk, struct sk_buff skb,
	129	const int len);
	130
7c657876 ACM	131	extern void dccp_init_xmit_timers(struct sock *sk);
	132	static inline void dccp_clear_xmit_timers(struct sock *sk)
	133	{
	134	inet_csk_clear_xmit_timers(sk);
	135	}
	136
	137	extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu);
	138
	139	extern const char *dccp_packet_name(const int type);
	140	extern const char *dccp_state_name(const int state);
	141
	142	static inline void dccp_set_state(struct sock *sk, const int state)
	143	{
	144	const int oldstate = sk->sk_state;
	145
	146	dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
	147	dccp_role(sk), sk,
	148	dccp_state_name(oldstate), dccp_state_name(state));
	149	WARN_ON(state == oldstate);
	150
	151	switch (state) {
	152	case DCCP_OPEN:
	153	if (oldstate != DCCP_OPEN)
	154	DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
	155	break;
	156
	157	case DCCP_CLOSED:
	158	if (oldstate == DCCP_CLOSING \|\| oldstate == DCCP_OPEN)
	159	DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
	160
	161	sk->sk_prot->unhash(sk);
	162	if (inet_csk(sk)->icsk_bind_hash != NULL &&
	163	!(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
	164	inet_put_port(&dccp_hashinfo, sk);
	165	/* fall through */
	166	default:
	167	if (oldstate == DCCP_OPEN)
	168	DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
	169	}
	170
	171	/* Change state AFTER socket is unhashed to avoid closed
	172	* socket sitting in hash tables.
	173	*/
	174	sk->sk_state = state;
	175	}
	176
	177	static inline void dccp_done(struct sock *sk)
	178	{
	179	dccp_set_state(sk, DCCP_CLOSED);
	180	dccp_clear_xmit_timers(sk);
	181
	182	sk->sk_shutdown = SHUTDOWN_MASK;
	183
	184	if (!sock_flag(sk, SOCK_DEAD))
	185	sk->sk_state_change(sk);
	186	else
	187	inet_csk_destroy_sock(sk);
	188	}
	189
	190	static inline void dccp_openreq_init(struct request_sock *req,
	191	struct dccp_sock *dp,
	192	struct sk_buff *skb)
	193	{
	194	/*
195	* FIXME: fill in the other req fields from the DCCP options
196	* received
197	*/
198	inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
199	inet_rsk(req)->acked = 0;
200	req->rcv_wnd = 0;
201	}
202
7c657876 ACM	203	extern int dccp_v4_conn_request(struct sock sk, struct sk_buff skb);
	204
	205	extern struct sock dccp_create_openreq_child(struct sock sk,
	206	const struct request_sock *req,
	207	const struct sk_buff *skb);
	208
	209	extern int dccp_v4_do_rcv(struct sock sk, struct sk_buff skb);
	210
	211	extern void dccp_v4_err(struct sk_buff *skb, u32);
	212
	213	extern int dccp_v4_rcv(struct sk_buff *skb);
	214
	215	extern struct sock dccp_v4_request_recv_sock(struct sock sk,
	216	struct sk_buff *skb,
	217	struct request_sock *req,
	218	struct dst_entry *dst);
	219	extern struct sock dccp_check_req(struct sock sk, struct sk_buff *skb,
	220	struct request_sock *req,
	221	struct request_sock **prev);
	222
	223	extern int dccp_child_process(struct sock parent, struct sock child,
	224	struct sk_buff *skb);
	225	extern int dccp_rcv_state_process(struct sock sk, struct sk_buff skb,
	226	struct dccp_hdr *dh, unsigned len);
	227	extern int dccp_rcv_established(struct sock sk, struct sk_buff skb,
	228	const struct dccp_hdr *dh, const unsigned len);
	229
	230	extern void dccp_close(struct sock *sk, long timeout);
	231	extern struct sk_buff dccp_make_response(struct sock sk,
	232	struct dst_entry *dst,
	233	struct request_sock *req);
a1d3a355 ACM	234	extern struct sk_buff dccp_make_reset(struct sock sk,
	235	struct dst_entry *dst,
	236	enum dccp_reset_codes code);
7c657876 ACM	237
	238	extern int dccp_connect(struct sock *sk);
	239	extern int dccp_disconnect(struct sock *sk, int flags);
	240	extern int dccp_getsockopt(struct sock *sk, int level, int optname,
a1d3a355 ACM	241	char __user optval, int __user optlen);
	242	extern int dccp_setsockopt(struct sock *sk, int level, int optname,
	243	char __user *optval, int optlen);
7c657876	244	extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg);
7690af3f ACM	245	extern int dccp_sendmsg(struct kiocb iocb, struct sock sk,
7690af3f ACM	246	struct msghdr *msg, size_t size);
7c657876 ACM	247	extern int dccp_recvmsg(struct kiocb iocb, struct sock sk,
	248	struct msghdr *msg, size_t len, int nonblock,
	249	int flags, int *addr_len);
7c657876 ACM	250	extern void dccp_shutdown(struct sock *sk, int how);
7c657876 ACM	251
95b81ef7 YN	252	extern int dccp_v4_checksum(const struct sk_buff *skb,
95b81ef7 YN	253	const u32 saddr, const u32 daddr);
7c657876	254
7690af3f ACM	255	extern int dccp_v4_send_reset(struct sock *sk,
7690af3f ACM	256	enum dccp_reset_codes code);
7c657876 ACM	257	extern void dccp_send_close(struct sock *sk);
	258
	259	struct dccp_skb_cb {
	260	__u8 dccpd_type;
	261	__u8 dccpd_reset_code;
	262	__u8 dccpd_service;
	263	__u8 dccpd_ccval;
	264	__u64 dccpd_seq;
	265	__u64 dccpd_ack_seq;
	266	int dccpd_opt_len;
	267	};
	268
	269	#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
	270
	271	static inline int dccp_non_data_packet(const struct sk_buff *skb)
	272	{
	273	const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
	274
	275	return type == DCCP_PKT_ACK \|\|
	276	type == DCCP_PKT_CLOSE \|\|
	277	type == DCCP_PKT_CLOSEREQ \|\|
	278	type == DCCP_PKT_RESET \|\|
	279	type == DCCP_PKT_SYNC \|\|
	280	type == DCCP_PKT_SYNCACK;
	281	}
	282
	283	static inline int dccp_packet_without_ack(const struct sk_buff *skb)
	284	{
	285	const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
	286
	287	return type == DCCP_PKT_DATA \|\| type == DCCP_PKT_REQUEST;
	288	}
	289
	290	#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
	291	#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)
	292
	293	static inline void dccp_set_seqno(u64 *seqno, u64 value)
	294	{
	295	if (value > DCCP_MAX_SEQNO)
	296	value -= DCCP_MAX_SEQNO + 1;
	297	*seqno = value;
	298	}
	299
	300	static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
	301	{
	302	return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
	303	}
	304
	305	static inline void dccp_inc_seqno(u64 *seqno)
	306	{
	307	if (++*seqno > DCCP_MAX_SEQNO)
	308	*seqno = 0;
	309	}
	310
	311	static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
	312	{
7690af3f ACM	313	struct dccp_hdr_ext dhx = (struct dccp_hdr_ext )((void *)dh +
7690af3f ACM	314	sizeof(*dh));
7c657876 ACM	315
	316	#if defined(__LITTLE_ENDIAN_BITFIELD)
	317	dh->dccph_seq = htonl((gss >> 32)) >> 8;
	318	#elif defined(__BIG_ENDIAN_BITFIELD)
	319	dh->dccph_seq = htonl((gss >> 32));
	320	#else
	321	#error "Adjust your <asm/byteorder.h> defines"
	322	#endif
	323	dhx->dccph_seq_low = htonl(gss & 0xffffffff);
	324	}
	325
7690af3f ACM	326	static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack,
7690af3f ACM	327	const u64 gsr)
7c657876 ACM	328	{
	329	#if defined(__LITTLE_ENDIAN_BITFIELD)
	330	dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8;
	331	#elif defined(__BIG_ENDIAN_BITFIELD)
	332	dhack->dccph_ack_nr_high = htonl((gsr >> 32));
	333	#else
	334	#error "Adjust your <asm/byteorder.h> defines"
	335	#endif
	336	dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff);
	337	}
	338
	339	static inline void dccp_update_gsr(struct sock *sk, u64 seq)
	340	{
	341	struct dccp_sock *dp = dccp_sk(sk);
	342	u64 tmp_gsr;
	343
7690af3f ACM	344	dccp_set_seqno(&tmp_gsr,
	345	(dp->dccps_gsr + 1 -
	346	(dp->dccps_options.dccpo_sequence_window / 4)));
7c657876 ACM	347	dp->dccps_gsr = seq;
	348	dccp_set_seqno(&dp->dccps_swl, max48(tmp_gsr, dp->dccps_isr));
	349	dccp_set_seqno(&dp->dccps_swh,
7690af3f ACM	350	(dp->dccps_gsr +
7690af3f ACM	351	(3 * dp->dccps_options.dccpo_sequence_window) / 4));
7c657876 ACM	352	}
	353
	354	static inline void dccp_update_gss(struct sock *sk, u64 seq)
	355	{
	356	struct dccp_sock *dp = dccp_sk(sk);
	357	u64 tmp_gss;
	358
7690af3f ACM	359	dccp_set_seqno(&tmp_gss,
	360	(dp->dccps_gss -
	361	dp->dccps_options.dccpo_sequence_window + 1));
7c657876 ACM	362	dp->dccps_awl = max48(tmp_gss, dp->dccps_iss);
	363	dp->dccps_awh = dp->dccps_gss = seq;
	364	}
	365
	366	extern void dccp_insert_options(struct sock sk, struct sk_buff skb);
	367	extern void dccp_insert_option_elapsed_time(struct sock *sk,
	368	struct sk_buff *skb,
	369	u32 elapsed_time);
	370	extern void dccp_insert_option(struct sock sk, struct sk_buff skb,
	371	unsigned char option,
	372	const void *value, unsigned char len);
	373
	374	extern struct socket *dccp_ctl_socket;
	375
	376	#define DCCP_ACKPKTS_STATE_RECEIVED 0
	377	#define DCCP_ACKPKTS_STATE_ECN_MARKED (1 << 6)
	378	#define DCCP_ACKPKTS_STATE_NOT_RECEIVED (3 << 6)
	379
	380	#define DCCP_ACKPKTS_STATE_MASK 0xC0 /* 11000000 */
	381	#define DCCP_ACKPKTS_LEN_MASK 0x3F /* 00111111 */
	382
	383	/** struct dccp_ackpkts - acknowledgeable packets
	384	*
	385	* This data structure is the one defined in the DCCP draft
	386	* Appendix A.
	387	*
	388	* @dccpap_buf_head - circular buffer head
	389	* @dccpap_buf_tail - circular buffer tail
7690af3f ACM	390	* @dccpap_buf_ackno - ack # of the most recent packet acknowledgeable in the
	391	* buffer (i.e. %dccpap_buf_head)
	392	* @dccpap_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
	393	* by the buffer with State 0
7c657876 ACM	394	*
	395	* Additionally, the HC-Receiver must keep some information about the
	396	* Ack Vectors it has recently sent. For each packet sent carrying an
	397	* Ack Vector, it remembers four variables:
	398	*
7690af3f ACM	399	* @dccpap_ack_seqno - the Sequence Number used for the packet
7690af3f ACM	400	* (HC-Receiver seqno)
7c657876	401	* @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
7690af3f ACM	402	* @dccpap_ack_ackno - the Acknowledgement Number used for the packet
7690af3f ACM	403	* (HC-Sender seqno)
7c657876 ACM	404	* @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
	405	*
	406	* @dccpap_buf_len - circular buffer length
	407	* @dccpap_buf - circular buffer of acknowledgeable packets
	408	*/
	409	struct dccp_ackpkts {
	410	unsigned int dccpap_buf_head;
	411	unsigned int dccpap_buf_tail;
	412	u64 dccpap_buf_ackno;
	413	u64 dccpap_ack_seqno;
	414	u64 dccpap_ack_ackno;
	415	unsigned int dccpap_ack_ptr;
	416	unsigned int dccpap_buf_vector_len;
	417	unsigned int dccpap_ack_vector_len;
	418	unsigned int dccpap_buf_len;
	419	unsigned long dccpap_time;
	420	u8 dccpap_buf_nonce;
	421	u8 dccpap_ack_nonce;
	422	u8 dccpap_buf[0];
	423	};
	424
a1d3a355 ACM	425	extern struct dccp_ackpkts *
	426	dccp_ackpkts_alloc(unsigned int len,
	427	const unsigned int __nocast priority);
7c657876 ACM	428	extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
	429	extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, u64 ackno, u8 state);
	430	extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
	431	struct sock *sk, u64 ackno);
	432
725ba8ee	433	#ifdef CONFIG_IP_DCCP_DEBUG
7c657876 ACM	434	extern void dccp_ackvector_print(const u64 ackno,
	435	const unsigned char *vector, int len);
	436	extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
	437	#else
	438	static inline void dccp_ackvector_print(const u64 ackno,
	439	const unsigned char *vector,
	440	int len) { }
	441	static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
	442	#endif
	443
	444	#endif /* _DCCP_H */