/*	$NetBSD: tp_pcb.h,v 1.22 2007/12/20 19:53:35 dyoung Exp $	*/

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)tp_pcb.h	8.2 (Berkeley) 9/22/94
 */

/***********************************************************
		Copyright IBM Corporation 1987

		      All Rights Reserved

Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the name of IBM not be
used in advertising or publicity pertaining to distribution of the
software without specific, written prior permission.

IBM DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
IBM BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
SOFTWARE.

******************************************************************/

/*
 * ARGO Project, Computer Sciences Dept., University of Wisconsin - Madison
 */
/*
 * This file defines the transport protocol control block (tpcb). and a bunch
 * of #define values that are used in the tpcb.
 */

#ifndef	 _NETISO_TP_PCB_H_
#define	 _NETISO_TP_PCB_H_

#include <netiso/tp_param.h>
#include <netiso/tp_timer.h>
#include <netiso/tp_user.h>
#ifndef sblock
#include <sys/socketvar.h>
#endif				/* sblock */

/*
 * NOTE: the code depends on REF_CLOSED > REF_OPEN > the rest, and on
 * REF_FREE being zero
 *
 * Possible improvement: think about merging the tp_ref w/ the tpcb and doing a
 * search through the tpcb list, from tpb. This would slow down lookup during
 * data transfer It would be a little nicer also to have something based on
 * the clock (like top n bits of the reference is part of the clock, to
 * minimize the likelihood  of reuse after a crash) also, need to keep the
 * timer servicing part to a minimum (although the cost of this is probably
 * independent of whether the timers are in the pcb or in an array.. Last,
 * would have to make the number of timers a function of the amount of mbufs
 * available, plus some for the frozen references.
 *
 * Possible improvement: Might not need the ref_state stuff either... REF_FREE
 * could correspond to tp_state == CLOSED or nonexistend tpcb, REF_OPEN to
 * tp_state anywhere from AK_WAIT or CR_SENT to CLOSING REF_OPENING could
 * correspond to LISTENING, because that's the way it's used, not because the
 * correspondence is exact. REF_CLOSED could correspond to REFWAIT
 */
#define REF_FROZEN 3		/* has ref timer only */
#define REF_OPEN 2		/* has timers, possibly active */
#define REF_OPENING 1		/* in use (has a pcb) but no timers */
#define REF_FREE 0		/* free to reallocate */

#define TM_NTIMERS		6
struct iso_addr;
struct sockaddr;
struct socket;
struct tp_pcb;
struct inpcb;

struct tp_ref {
	struct tp_pcb  *tpr_pcb;/* back ptr to PCB */
};

/* PER system stuff (one static structure instead of a bunch of names) */
struct tp_refinfo {
	struct tp_ref  *tpr_base;
	int		tpr_size;
	int		tpr_maxopen;
	int		tpr_numopen;
};

struct nl_protosw {
	int		nlp_afamily;	/* address family */
	void		(*nlp_putnetaddr)	/* puts addresses in nl pcb */
				(void *, struct sockaddr *, int);
	void		(*nlp_getnetaddr)	/* gets addresses from nl pcb */
				(void *, struct mbuf *, int);
	int		(*nlp_cmpnetaddr)	/* compares address in pcb */
				(void *, struct sockaddr *, int);
						/* with sockaddr */
	void		(*nlp_putsufx)		/* puts transport suffixes in */
				(void *, void *, int, int);
						/* nl pcb */
	void		(*nlp_getsufx)		/* gets transport suffixes */
				(void *, u_short *, void *, int);
						/* from nl pcb */
	void		(*nlp_recycle_suffix)	/* clears suffix from nl pcb */
				(void *);
	int		(*nlp_mtu)		/* figures out mtu based on */
				(void *);	/* nl used */
	int		(*nlp_pcbbind)		/* bind to pcb for net level */
				(void *, struct mbuf *, struct lwp *);
	int		(*nlp_pcbconn)		/* connect for net level */
				(void *, struct mbuf *, struct lwp *);
	void		(*nlp_pcbdisc)		/* disconnect net level */
				(void *);
	void		(*nlp_pcbdetach)	/* detach net level pcb */
				(void *);
	int		(*nlp_pcballoc)		/* allocate a net level pcb */
				(struct socket *, void *);
	int		(*nlp_output)		/* prepare a packet to give */
				(struct mbuf *, ...); /* to nl */
	int		(*nlp_dgoutput)		/* prepare a packet to give */
				(struct mbuf *, ...); /*to nl*/
	int		(*nlp_ctloutput)	/* hook for network set/get */
				(int, int, void *, struct mbuf *);
						/* options */
	void *		nlp_pcblist;	/* list of xx_pcb's for connections */
};


struct tp_pcb {
	struct tp_pcb  *tp_next;
	struct tp_pcb  *tp_prev;
	struct tp_pcb  *tp_nextlisten;	/* chain all listeners */
	struct socket  *tp_sock;/* back ptr */
	u_short		tp_state;	/* state of fsm */
	short		tp_retrans;	/* # times can still retrans */
	void *		tp_npcb;/* to lower layer pcb */
	struct nl_protosw *tp_nlproto;	/* lower-layer dependent routines */
	struct route	*tp_routep;	/* obtain mtu; inside npcb */


	RefNum		tp_lref;/* local reference */
	RefNum		tp_fref;/* foreign reference */

	u_int		tp_seqmask;	/* mask for seq space */
	u_int		tp_seqbit;	/* bit for seq number wraparound */
	u_int		tp_seqhalf;	/* half the seq space */

	struct mbuf    *tp_ucddata;	/* user connect/disconnect data */

	/* credit & sequencing info for SENDING */
	u_short		tp_fcredit;	/* current remote credit in # packets */
	u_short		tp_maxfcredit;	/* max remote credit in # packets */
	u_short		tp_dupacks;	/* intuit packet loss before rxt timo */
	u_long		tp_cong_win;	/* congestion window in bytes. see
					 * profuse comments in TCP code */
	u_long		tp_ssthresh;	/* cong_win threshold for slow start
					 * exponential to linear switch */
	SeqNum		tp_snduna;	/* seq # of lowest unacked DT */
	SeqNum		tp_sndnew;	/* seq # of lowest unsent DT  */
	SeqNum		tp_sndnum;	/* next seq # to be assigned */
	SeqNum		tp_sndnxt;	/* what to do next; poss. rxt */
	struct mbuf    *tp_sndnxt_m;	/* packet corres. to sndnxt */
	int		tp_Nwindow;	/* for perf. measurement */

	/* credit & sequencing info for RECEIVING */
	SeqNum		tp_rcvnxt;	/* next DT seq # expect to recv */
	SeqNum		tp_sent_lcdt;	/* cdt according to last ack sent */
	SeqNum		tp_sent_uwe;	/* uwe according to last ack sent */
	SeqNum		tp_sent_rcvnxt; /* rcvnxt according to last ack sent
					 * needed for perf measurements only */
	u_short		tp_lcredit;	/* current local credit in # packets */
	u_short		tp_maxlcredit;	/* needed for reassembly queue */
	struct mbuf   **tp_rsyq;/* unacked stuff recvd out of order */
	int		tp_rsycnt;	/* number of packets "" "" "" ""    */
	u_long		tp_rhiwat;	/* remember original RCVBUF size */

	/* receiver congestion state stuff ...	*/
	u_int		tp_win_recv;

	/* receive window as a scaled int (8 bit fraction part) */

	struct cong_sample {
		ushort		cs_size;	/* current window size */
		ushort		cs_received;	/* PDUs received in this
						 * sample */
		ushort		cs_ce_set;	/* PDUs received in this
						 * sample with CE bit set */
	}		tp_cong_sample;


	/* parameters per-connection controllable by user */
	struct tp_conn_param _tp_param;

#define tp_Nretrans _tp_param.p_Nretrans
#define tp_dr_ticks _tp_param.p_dr_ticks
#define tp_cc_ticks _tp_param.p_cc_ticks
#define tp_dt_ticks _tp_param.p_dt_ticks
#define tp_xpd_ticks _tp_param.p_x_ticks
#define tp_cr_ticks _tp_param.p_cr_ticks
#define tp_keepalive_ticks _tp_param.p_keepalive_ticks
#define tp_sendack_ticks _tp_param.p_sendack_ticks
#define tp_refer_ticks _tp_param.p_ref_ticks
#define tp_inact_ticks _tp_param.p_inact_ticks
#define tp_xtd_format _tp_param.p_xtd_format
#define tp_xpd_service _tp_param.p_xpd_service
#define tp_ack_strat _tp_param.p_ack_strat
#define tp_rx_strat _tp_param.p_rx_strat
#define tp_use_checksum _tp_param.p_use_checksum
#define tp_use_efc _tp_param.p_use_efc
#define tp_use_nxpd _tp_param.p_use_nxpd
#define tp_use_rcc _tp_param.p_use_rcc
#define tp_tpdusize _tp_param.p_tpdusize
#define tp_class _tp_param.p_class
#define tp_winsize _tp_param.p_winsize
#define tp_no_disc_indications _tp_param.p_no_disc_indications
#define tp_dont_change_params _tp_param.p_dont_change_params
#define tp_netservice _tp_param.p_netservice
#define tp_version _tp_param.p_version
#define tp_ptpdusize _tp_param.p_ptpdusize

	int		tp_l_tpdusize;
	/*
	 * whereas tp_tpdusize is log2(the negotiated max size) l_tpdusize is
	 * the size we'll use when sending, in # chars
	 */

	int		tp_rtv; /* max round-trip time variance */
	int		tp_rtt; /* smoothed round-trip time */
	SeqNum		tp_rttseq;	/* packet being timed */
	int		tp_rttemit;	/* when emitted, in ticks */
	int		tp_idle;/* last activity, in ticks */
	short		tp_rxtcur;	/* current retransmit value */
	short		tp_rxtshift;	/* log(2) of rexmt exp. backoff */
	u_char		tp_cebit_off;	/* real DEC bit algorithms not in use */
	u_char		tp_oktonagle;	/* Last unsent pckt may be append to */
	u_char		tp_flags;	/* values: */
#define TPF_NLQOS_PDN		TPFLAG_NLQOS_PDN
#define TPF_PEER_ON_SAMENET	TPFLAG_PEER_ON_SAMENET
#define TPF_GENERAL_ADDR	TPFLAG_GENERAL_ADDR
#define TPF_DELACK			0x8
#define TPF_ACKNOW			0x10

#define PEER_IS_LOCAL(t)	(((t)->tp_flags & TPF_PEER_ON_SAME_NET) != 0)
#define USES_PDN(t)			(((t)->tp_flags & TPF_NLQOS_PDN) != 0)


	unsigned
			tp_sendfcc:1,	/* shall next ack include FCC
					 * parameter? */
			tp_trace:1,	/* is this pcb being traced? (not
					 * used yet) */
			tp_perf_on:1,	/* 0/1 -> performance measuring on  */
			tp_reneged:1,	/* have we reneged on cdt since last
					 * ack? */
			tp_decbit:3,	/* dec bit was set, we're in reneg
					 * mode	 */
			tp_notdetached:1;	/* Call tp_detach before
						 * freeing XXXXXXX */

#ifdef TP_PERF_MEAS
	/* performance stats - see tp_stat.h */
	struct tp_pmeas *tp_p_meas;
#endif				/* TP_PERF_MEAS */

	/* addressing */
	u_short		tp_domain;	/* domain (INET, ISO) */
	/*
	 * for compatibility with the *old* way and with INET, be sure that
	 * that lsuffix and fsuffix are aligned to a short addr. having them
	 * follow the u_short *suffixlen should suffice (choke)
	 */
	u_short		tp_fsuffixlen;	/* foreign suffix */
	char		tp_fsuffix[MAX_TSAP_SEL_LEN];
	u_short		tp_lsuffixlen;	/* local suffix */
	char		tp_lsuffix[MAX_TSAP_SEL_LEN];
#define SHORT_LSUFXP(tpcb) ((short *)((tpcb)->tp_lsuffix))
#define SHORT_FSUFXP(tpcb) ((short *)((tpcb)->tp_fsuffix))

	/* Timer stuff */
	u_char		tp_vers;/* protocol version */
	u_char		tp_peer_acktime;	/* used for DT retrans time */
	u_char		tp_refstate;	/* values REF_FROZEN, etc. above */
	struct tp_pcb  *tp_fasttimeo;	/* limit pcbs to examine */
	u_int		tp_timer[TM_NTIMERS];	/* C timers */

	struct sockbuf	tp_Xsnd;		/* for expedited data */
#if 0
	struct sockbuf	tp_Xrcv;		/* for expedited data */
#else
#define tp_Xrcv tp_sock->so_rcv
#endif
	SeqNum		tp_Xsndnxt;	/* next XPD seq # to send */
	SeqNum		tp_Xuna;/* seq # of unacked XPD */
	SeqNum		tp_Xrcvnxt;	/* next XPD seq # expect to recv */

	/* AK subsequencing */
	u_short		tp_s_subseq;	/* next subseq to send */
	u_short		tp_r_subseq;	/* highest recv subseq */

};

extern	u_int	tp_start_win;

#define ROUND(scaled_int) (((scaled_int) >> 8) + (((scaled_int) & 0x80) ? 1:0))

/* to round off a scaled int with an 8 bit fraction part */

#define CONG_INIT_SAMPLE(pcb) \
	pcb->tp_cong_sample.cs_received = \
    pcb->tp_cong_sample.cs_ce_set = 0; \
    pcb->tp_cong_sample.cs_size = max(pcb->tp_lcredit, 1) << 1;

#define CONG_UPDATE_SAMPLE(pcb, ce_bit) \
    pcb->tp_cong_sample.cs_received++; \
    if (ce_bit) { \
	pcb->tp_cong_sample.cs_ce_set++; \
    } \
    if (pcb->tp_cong_sample.cs_size <= pcb->tp_cong_sample.cs_received) { \
	if ((pcb->tp_cong_sample.cs_ce_set << 1) >=  \
		    pcb->tp_cong_sample.cs_size ) { \
	    pcb->tp_win_recv -= pcb->tp_win_recv >> 3; /* multiply by .875 */ \
	    pcb->tp_win_recv = max(1 << 8, pcb->tp_win_recv); \
	} \
	else { \
	    pcb->tp_win_recv += (1 << 8); /* add one to the scaled int */ \
	} \
	pcb->tp_lcredit = ROUND(pcb->tp_win_recv); \
	CONG_INIT_SAMPLE(pcb); \
    }

#ifdef _KERNEL
extern struct tp_refinfo tp_refinfo;
extern struct tp_ref *tp_ref;
extern struct tp_param tp_param;
extern struct nl_protosw nl_protosw[];
extern struct tp_pcb *tp_listeners;
extern struct tp_pcb *tp_ftimeolist;
#endif

#define sototpcb(so)	((struct tp_pcb *)(so->so_pcb))
#define sototpref(so)	((sototpcb(so)->tp_ref))
#define tpcbtoso(tp)	((struct socket *)((tp)->tp_sock))
#define tpcbtoref(tp)	((struct tp_ref *)((tp)->tp_ref))

#endif /* !_NETISO_TP_PCB_H_ */
