tp_subr2.c

早期freebsd实现

 */

int
tp_mask_to_num(x)
	u_char x;
{
	register int j;

	for(j = 4; j>=0 ;j--) {
		if(x & (1<<j))
			break;
	}
	ASSERT( (j == 4) || (j == 0) ); /* for now */
	if( (j != 4) && (j != 0) ) {
		printf("ASSERTION ERROR: tp_mask_to_num: x 0x%x j %d\n",
			x, j);
	}
	IFTRACE(D_TPINPUT)
		tptrace(TPPTmisc, "tp_mask_to_num(x) returns j", x, j, 0, 0);
	ENDTRACE
	IFDEBUG(D_TPINPUT)
		printf("tp_mask_to_num(0x%x) returns 0x%x\n", x, j);
	ENDDEBUG
	return j;
}

static 
copyQOSparms(src, dst)
	struct tp_conn_param *src, *dst;
{
	/* copy all but the bits stuff at the end */
#define COPYSIZE (12 * sizeof(short))

	bcopy((caddr_t)src, (caddr_t)dst, COPYSIZE);
	dst->p_tpdusize = src->p_tpdusize;
	dst->p_ack_strat = src->p_ack_strat;
	dst->p_rx_strat = src->p_rx_strat;
#undef COPYSIZE
}
/*
 * Determine a reasonable value for maxseg size.
 * If the route is known, check route for mtu.
 * We also initialize the congestion/slow start
 * window to be a single segment if the destination isn't local.
 * While looking at the routing entry, we also initialize other path-dependent
 * parameters from pre-set or cached values in the routing entry.
 */
void
tp_mss(tpcb, nhdr_size)
	register struct tp_pcb *tpcb;
	int nhdr_size;
{
	register struct rtentry *rt;
	struct ifnet *ifp;
	register int rtt, mss;
	u_long bufsize;
	int i, ssthresh = 0, rt_mss;
	struct socket *so;

	if (tpcb->tp_ptpdusize)
		mss = tpcb->tp_ptpdusize << 7;
	else
		mss = 1 << tpcb->tp_tpdusize;
	so = tpcb->tp_sock;
	if ((rt = *(tpcb->tp_routep)) == 0) {
		bufsize = so->so_rcv.sb_hiwat;
		goto punt_route;
	}
	ifp = rt->rt_ifp;

#ifdef RTV_MTU	/* if route characteristics exist ... */
	/*
	 * While we're here, check if there's an initial rtt
	 * or rttvar.  Convert from the route-table units
	 * to hz ticks for the smoothed timers and slow-timeout units
	 * for other inital variables.
	 */
	if (tpcb->tp_rtt == 0 && (rtt = rt->rt_rmx.rmx_rtt)) {
		tpcb->tp_rtt = rtt * hz / RTM_RTTUNIT;
		if (rt->rt_rmx.rmx_rttvar)
			tpcb->tp_rtv = rt->rt_rmx.rmx_rttvar
						* hz / RTM_RTTUNIT;
		else
			tpcb->tp_rtv = tpcb->tp_rtt;
	}
	/*
	 * if there's an mtu associated with the route, use it
	 */
	if (rt->rt_rmx.rmx_mtu)
		rt_mss = rt->rt_rmx.rmx_mtu - nhdr_size;
	else
#endif /* RTV_MTU */
		rt_mss = (ifp->if_mtu - nhdr_size);
	if (tpcb->tp_ptpdusize == 0 || /* assume application doesn't care */
	    mss > rt_mss /* network won't support what was asked for */)
		mss = rt_mss;
	/* can propose mtu which are multiples of 128 */
	mss &= ~0x7f;
	/*
	 * If there's a pipesize, change the socket buffer
	 * to that size.
	 */
#ifdef RTV_SPIPE
	if ((bufsize = rt->rt_rmx.rmx_sendpipe) > 0) {
#endif
		bufsize = min(bufsize, so->so_snd.sb_hiwat);
		(void) sbreserve(&so->so_snd, bufsize);
	}
#ifdef RTV_SPIPE
	if ((bufsize = rt->rt_rmx.rmx_recvpipe) > 0) {
#endif
		bufsize = min(bufsize, so->so_rcv.sb_hiwat);
		(void) sbreserve(&so->so_rcv, bufsize);
	} else
		bufsize = so->so_rcv.sb_hiwat;
#ifdef RTV_SSTHRESH
	/*
	 * There's some sort of gateway or interface
	 * buffer limit on the path.  Use this to set
	 * the slow start threshhold, but set the
	 * threshold to no less than 2*mss.
	 */
	ssthresh = rt->rt_rmx.rmx_ssthresh;
punt_route:
	/*
	 * The current mss is initialized to the default value.
	 * If we compute a smaller value, reduce the current mss.
	 * If we compute a larger value, return it for use in sending
	 * a max seg size option.
	 * If we received an offer, don't exceed it.
	 * However, do not accept offers under 128 bytes.
	 */
	if (tpcb->tp_l_tpdusize)
		mss = min(mss, tpcb->tp_l_tpdusize);
	/*
	 * We want a minimum recv window of 4 packets to
	 * signal packet loss by duplicate acks.
	 */
	mss = min(mss, bufsize >> 2) & ~0x7f;
	mss = max(mss, 128);		/* sanity */
	tpcb->tp_cong_win =
		(rt == 0 || (rt->rt_flags & RTF_GATEWAY)) ? mss : bufsize;
	tpcb->tp_l_tpdusize = mss;
	tp_rsyset(tpcb);
	tpcb->tp_ssthresh = max(2 * mss, ssthresh);
	/* Calculate log2 of mss */
	for (i = TP_MIN_TPDUSIZE + 1; i <= TP_MAX_TPDUSIZE; i++)
		if ((1 << i) > mss)
			break;
	i--;
	tpcb->tp_tpdusize = i;
#endif /* RTV_MTU */
}

/*
 * CALLED FROM:
 *  tp_usrreq on PRU_CONNECT and tp_input on receipt of CR
 *	
 * FUNCTION and ARGUMENTS:
 * 	-- An mbuf containing the peer's network address.
 *  -- Our control block, which will be modified
 *  -- In the case of cons, a control block for that layer.
 *
 *	
 * RETURNS:
 *	errno value	 : 
 *	EAFNOSUPPORT if can't find an nl_protosw for x.25 (really could panic)
 *	ECONNREFUSED if trying to run TP0 with non-type 37 address
 *  possibly other E* returned from cons_netcmd()
 *
 * SIDE EFFECTS:
 *   Determines recommended tpdusize, buffering and intial delays
 *	 based on information cached on the route.
 */
int
tp_route_to( m, tpcb, channel)
	struct mbuf					*m;
	register struct tp_pcb		*tpcb;
	caddr_t 					channel;
{
	register struct sockaddr_iso *siso;	/* NOTE: this may be a sockaddr_in */
	extern struct tp_conn_param tp_conn_param[];
	int error = 0, save_netservice = tpcb->tp_netservice;
	register struct rtentry *rt = 0;
	int nhdr_size, mtu, bufsize;

	siso = mtod(m, struct sockaddr_iso *);
	IFTRACE(D_CONN)
		tptraceTPCB(TPPTmisc, 
		"route_to: so  afi netservice class",
		tpcb->tp_sock, siso->siso_addr.isoa_genaddr[0], tpcb->tp_netservice,
			tpcb->tp_class);
	ENDTRACE
	IFDEBUG(D_CONN)
		printf("tp_route_to( m x%x, channel 0x%x, tpcb 0x%x netserv 0x%x)\n", 
			m, channel, tpcb, tpcb->tp_netservice);
		printf("m->mlen x%x, m->m_data:\n", m->m_len);
		dump_buf(mtod(m, caddr_t), m->m_len);
	ENDDEBUG
	if (channel) {
#ifdef TPCONS
		struct pklcd *lcp = (struct pklcd *)channel;
		struct isopcb *isop = (struct isopcb *)lcp->lcd_upnext,
			*isop_new = (struct isopcb *)tpcb->tp_npcb;
		/* The next 2 lines believe that you haven't
		   set any network level options or done a pcbconnect
		   and XXXXXXX'edly apply to both inpcb's and isopcb's */
		remque(isop_new);
		free(isop_new, M_PCB);
		tpcb->tp_npcb = (caddr_t)isop;
		tpcb->tp_netservice = ISO_CONS;
		tpcb->tp_nlproto = nl_protosw + ISO_CONS;
		if (isop->isop_refcnt++ == 0) {
			iso_putsufx(isop, tpcb->tp_lsuffix, tpcb->tp_lsuffixlen, TP_LOCAL);
			isop->isop_socket = tpcb->tp_sock;
		} else
			/* there are already connections sharing this */;
#endif
	} else {
		switch (siso->siso_family) {
		default:
			error = EAFNOSUPPORT;
			goto done;
#ifdef ISO
		case AF_ISO:
		{
			struct isopcb *isop = (struct isopcb *)tpcb->tp_npcb;
			int flags = tpcb->tp_sock->so_options & SO_DONTROUTE;
			tpcb->tp_netservice = ISO_CLNS;
			if (clnp_route(&siso->siso_addr, &isop->isop_route,
							flags, (void **)0, (void **)0) == 0) {
				rt = isop->isop_route.ro_rt;
				if (rt && rt->rt_flags & RTF_PROTO1)
					tpcb->tp_netservice = ISO_CONS;
			}
		}    break;
#endif
#ifdef INET
		case AF_INET:
			tpcb->tp_netservice = IN_CLNS;
#endif
		}
		if (tpcb->tp_nlproto->nlp_afamily != siso->siso_family) {
			IFDEBUG(D_CONN)
				printf("tp_route_to( CHANGING nlproto old 0x%x new 0x%x)\n", 
						save_netservice, tpcb->tp_netservice);
			ENDDEBUG
			if (error = tp_set_npcb(tpcb))
				goto done;
		}
		IFDEBUG(D_CONN)
			printf("tp_route_to  calling nlp_pcbconn, netserv %d\n",
				tpcb->tp_netservice);
		ENDDEBUG
		tpcb->tp_nlproto = nl_protosw + tpcb->tp_netservice;
		error = (tpcb->tp_nlproto->nlp_pcbconn)(tpcb->tp_npcb, m);
	}
	if (error)
		goto done;
	nhdr_size = tpcb->tp_nlproto->nlp_mtu(tpcb); /* only gets common info */
	tp_mss(tpcb, nhdr_size);
done:
	IFDEBUG(D_CONN)
		printf("tp_route_to  returns 0x%x\n", error);
	ENDDEBUG
	IFTRACE(D_CONN)
		tptraceTPCB(TPPTmisc, "route_to: returns: error netserv class", error, 
			tpcb->tp_netservice, tpcb->tp_class, 0);
	ENDTRACE
	return error;
}


/* class zero version */
void
tp0_stash( tpcb, e )
	register struct tp_pcb		*tpcb;
	register struct tp_event	*e;
{
#ifndef lint
#define E e->ATTR(DT_TPDU)
#else /* lint */
#define E e->ev_union.EV_DT_TPDU
#endif /* lint */

	register struct sockbuf *sb = &tpcb->tp_sock->so_rcv;
	register struct isopcb *isop = (struct isopcb *)tpcb->tp_npcb;

	IFPERF(tpcb)
		PStat(tpcb, Nb_from_ll) += E.e_datalen;
		tpmeas(tpcb->tp_lref, TPtime_from_ll, &e->e_time,
				E.e_seq, PStat(tpcb, Nb_from_ll), E.e_datalen);
	ENDPERF

	IFDEBUG(D_STASH)
		printf("stash EQ: seq 0x%x datalen 0x%x eot 0x%x", 
		E.e_seq, E.e_datalen, E.e_eot);
	ENDDEBUG

	IFTRACE(D_STASH)
		tptraceTPCB(TPPTmisc, "stash EQ: seq len eot", 
		E.e_seq, E.e_datalen, E.e_eot, 0);
	ENDTRACE

	if ( E.e_eot ) {
		register struct mbuf *n = E.e_data;
		n->m_flags |= M_EOR;
		n->m_act = MNULL; /* set on tp_input */
	}
	sbappend(sb, E.e_data);
	IFDEBUG(D_STASH)
		dump_mbuf(sb->sb_mb, "stash 0: so_rcv after appending");
	ENDDEBUG
	if (tpcb->tp_netservice != ISO_CONS)
		printf("tp0_stash: tp running over something wierd\n");
	else {
		register struct pklcd *lcp = (struct pklcd *)isop->isop_chan;
		pk_flowcontrol(lcp, sbspace(sb) <= 0, 1);
	}
} 

void
tp0_openflow(tpcb)
register struct tp_pcb *tpcb;
{
	register struct isopcb *isop = (struct isopcb *)tpcb->tp_npcb;
	if (tpcb->tp_netservice != ISO_CONS)
		printf("tp0_openflow: tp running over something wierd\n");
	else {
		register struct pklcd *lcp = (struct pklcd *)isop->isop_chan;
		if (lcp->lcd_rxrnr_condition)
			pk_flowcontrol(lcp, 0, 0);
	}
}
#ifndef TPCONS
static
pk_flowcontrol() {}
#endif

#ifdef TP_PERF_MEAS
/*
 * CALLED FROM:
 *  tp_ctloutput() when the user sets TPOPT_PERF_MEAS on
 *  and tp_newsocket() when a new connection is made from 
 *  a listening socket with tp_perf_on == true.
 * FUNCTION and ARGUMENTS:
 *  (tpcb) is the usual; this procedure gets a clear cluster mbuf for
 *  a tp_pmeas structure, and makes tpcb->tp_p_meas point to it.
 * RETURN VALUE:
 *  ENOBUFS if it cannot get a cluster mbuf.
 */

int 
tp_setup_perf(tpcb)
	register struct tp_pcb *tpcb;
{
	register struct mbuf *q;

	if( tpcb->tp_p_meas == 0 ) {
		MGET(q, M_WAITOK, MT_PCB);
		if (q == 0)
			return ENOBUFS;
		MCLGET(q, M_WAITOK);
		if ((q->m_flags & M_EXT) == 0) {
			(void) m_free(q);
			return ENOBUFS;
		}
		q->m_len = sizeof (struct tp_pmeas);
		tpcb->tp_p_mbuf = q;
		tpcb->tp_p_meas = mtod(q, struct tp_pmeas *);
		bzero( (caddr_t)tpcb->tp_p_meas, sizeof (struct tp_pmeas) );
		IFDEBUG(D_PERF_MEAS)
			printf(
			"tpcb 0x%x so 0x%x ref 0x%x tp_p_meas 0x%x tp_perf_on 0x%x\n", 
				tpcb, tpcb->tp_sock, tpcb->tp_lref, 
				tpcb->tp_p_meas, tpcb->tp_perf_on);
		ENDDEBUG
		tpcb->tp_perf_on = 1;
	}
	return 0;
}
#endif /* TP_PERF_MEAS */

#ifdef ARGO_DEBUG
dump_addr (addr)
	register struct sockaddr *addr;
{
	switch( addr->sa_family ) {
		case AF_INET:
			dump_inaddr((struct sockaddr_in *)addr);
			break;
#ifdef ISO
		case AF_ISO:
			dump_isoaddr((struct sockaddr_iso *)addr);
			break;
#endif /* ISO */
		default:
			printf("BAD AF: 0x%x\n", addr->sa_family);
			break;
	}
}

#define	MAX_COLUMNS	8
/*
 *	Dump the buffer to the screen in a readable format. Format is:
 *
 *		hex/dec  where hex is the hex format, dec is the decimal format.
 *		columns of hex/dec numbers will be printed, followed by the
 *		character representations (if printable).
 */
Dump_buf(buf, len)
caddr_t	buf;
int		len;
{
	int		i,j;
#define Buf ((u_char *)buf)
	printf("Dump buf 0x%x len 0x%x\n", buf, len);
	for (i = 0; i < len; i += MAX_COLUMNS) {
		printf("+%d:\t", i);
		for (j = 0; j < MAX_COLUMNS; j++) {
			if (i + j < len) {
				printf("%x/%d\t", Buf[i+j], Buf[i+j]);
			} else {
				printf("	");
			}
		}

		for (j = 0; j < MAX_COLUMNS; j++) {
			if (i + j < len) {
				if (((Buf[i+j]) > 31) && ((Buf[i+j]) < 128))
					printf("%c", Buf[i+j]);
				else
					printf(".");
			}
		}
		printf("\n");
	}
}
#endif /* ARGO_DEBUG */