tp_pcb.c

早期freebsd实现

tp_freeref(n)
RefNum n;
{
	register struct tp_ref *r = tp_ref + n;
	register struct tp_pcb *tpcb;

	tpcb = r->tpr_pcb;
	IFDEBUG(D_TIMER)
		printf("tp_freeref called for ref %d pcb %x maxrefopen %d\n", 
		n, tpcb, tp_refinfo.tpr_maxopen);
	ENDDEBUG
	IFTRACE(D_TIMER)
		tptrace(TPPTmisc, "tp_freeref ref maxrefopen pcb",
		n, tp_refinfo.tpr_maxopen, tpcb, 0);
	ENDTRACE
	if (tpcb == 0)
		return;
	IFDEBUG(D_CONN)
		printf("tp_freeref: CLEARING tpr_pcb 0x%x\n", tpcb);
	ENDDEBUG
	r->tpr_pcb = (struct tp_pcb *)0;
	tpcb->tp_refstate = REF_FREE;

	for (r = tp_ref + tp_refinfo.tpr_maxopen; r > tp_ref; r--)
		if (r->tpr_pcb)
			break;
	tp_refinfo.tpr_maxopen = r - tp_ref;
	tp_refinfo.tpr_numopen--;

	IFDEBUG(D_TIMER)
		printf("tp_freeref ends w/ maxrefopen %d\n", tp_refinfo.tpr_maxopen);
	ENDDEBUG
}

/*
 * NAME:  tp_getref()
 *
 * CALLED FROM:
 *  tp_attach()
 *
 * FUNCTION and ARGUMENTS:
 *  obtains the next free reference and allocates the appropriate
 *  ref structure, links that structure to (tpcb) 
 *
 * RETURN VALUE:
 *	a reference number
 *  or TP_ENOREF
 *
 * SIDE EFFECTS:
 *
 * NOTES:
 */
u_long
tp_getref(tpcb) 
	register struct tp_pcb *tpcb;
{
	register struct tp_ref	*r, *rlim;
	register int 			i;
	caddr_t obase;
	unsigned size;

	if (++tp_refinfo.tpr_numopen < tp_refinfo.tpr_size)
		for (r = tp_refinfo.tpr_base, rlim = r + tp_refinfo.tpr_size;
								++r < rlim; ) 	/* tp_ref[0] is never used */
			if (r->tpr_pcb == 0)
				goto got_one;
	/* else have to allocate more space */

	obase = (caddr_t)tp_refinfo.tpr_base;
	size = tp_refinfo.tpr_size * sizeof(struct tp_ref);
	r = (struct tp_ref *) malloc(size + size, M_PCB, M_NOWAIT);
	if (r == 0)
		return (--tp_refinfo.tpr_numopen, TP_ENOREF);
	tp_refinfo.tpr_base = tp_ref = r;
	tp_refinfo.tpr_size *= 2;
	bcopy(obase, (caddr_t)r, size);
	free(obase, M_PCB);
	r = (struct tp_ref *)(size + (caddr_t)r);
	bzero((caddr_t)r, size);

got_one:
	r->tpr_pcb = tpcb;
	tpcb->tp_refstate = REF_OPENING;
	i = r - tp_refinfo.tpr_base;
	if (tp_refinfo.tpr_maxopen < i) 
		tp_refinfo.tpr_maxopen = i;
	return (u_long)i;
}

/*
 * NAME: tp_set_npcb()
 *
 * CALLED FROM:
 *	tp_attach(), tp_route_to()
 *
 * FUNCTION and ARGUMENTS:
 *  given a tpcb, allocate an appropriate lower-lever npcb, freeing
 *  any old ones that might need re-assigning.
 */
tp_set_npcb(tpcb)
register struct tp_pcb *tpcb;
{
	register struct socket *so = tpcb->tp_sock;
	int error;

	if (tpcb->tp_nlproto && tpcb->tp_npcb) {
		short so_state = so->so_state;
		so->so_state &= ~SS_NOFDREF;
		tpcb->tp_nlproto->nlp_pcbdetach(tpcb->tp_npcb);
		so->so_state = so_state;
	}
	tpcb->tp_nlproto = &nl_protosw[tpcb->tp_netservice];
	/* xx_pcballoc sets so_pcb */
	error = tpcb->tp_nlproto->nlp_pcballoc(so, tpcb->tp_nlproto->nlp_pcblist);
	tpcb->tp_npcb = so->so_pcb;
	so->so_pcb = (caddr_t)tpcb;
	return (error);
}
/*
 * NAME: tp_attach()
 *
 * CALLED FROM:
 *	tp_usrreq, PRU_ATTACH
 *
 * FUNCTION and ARGUMENTS:
 *  given a socket (so) and a protocol family (dom), allocate a tpcb
 *  and ref structure, initialize everything in the structures that
 *  needs to be initialized.
 *
 * RETURN VALUE:
 *  0 ok
 *  EINVAL if DEBUG(X) in is on and a disaster has occurred
 *  ENOPROTOOPT if TP hasn't been configured or if the
 *   socket wasn't created with tp as its protocol
 *  EISCONN if this socket is already part of a connection
 *  ETOOMANYREFS if ran out of tp reference numbers.
 *  E* whatever error is returned from soreserve()
 *    for from the network-layer pcb allocation routine
 *
 * SIDE EFFECTS:
 *
 * NOTES:
 */
tp_attach(so, protocol)
	struct socket 			*so;
	int 					protocol;
{
	register struct tp_pcb	*tpcb;
	int 					error = 0;
	int 					dom = so->so_proto->pr_domain->dom_family;
	u_long					lref;
	extern struct tp_conn_param tp_conn_param[];

	IFDEBUG(D_CONN)
		printf("tp_attach:dom 0x%x so 0x%x ", dom, so);
	ENDDEBUG
	IFTRACE(D_CONN)
		tptrace(TPPTmisc, "tp_attach:dom so", dom, so, 0, 0);
	ENDTRACE

	if (so->so_pcb != NULL) { 
		return EISCONN;	/* socket already part of a connection*/
	}

	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0)
		error = soreserve(so, tp_sendspace, tp_recvspace);
		/* later an ioctl will allow reallocation IF still in closed state */

	if (error)
		goto bad2;

	MALLOC(tpcb, struct tp_pcb *, sizeof(*tpcb), M_PCB, M_NOWAIT);
	if (tpcb == NULL) {
		error = ENOBUFS;
		goto bad2;
	}
	bzero( (caddr_t)tpcb, sizeof (struct tp_pcb) );

	if ( ((lref = tp_getref(tpcb)) &  TP_ENOREF) != 0 ) { 
		error = ETOOMANYREFS; 
		goto bad3;
	}
	tpcb->tp_lref = lref;
	tpcb->tp_sock =  so;
	tpcb->tp_domain = dom;
	tpcb->tp_rhiwat = so->so_rcv.sb_hiwat;
	/* tpcb->tp_proto = protocol; someday maybe? */
	if (protocol && protocol<ISOPROTO_TP4) {
		tpcb->tp_netservice = ISO_CONS;
		tpcb->tp_snduna = (SeqNum) -1;/* kludge so the pseudo-ack from the CR/CC
								 * will generate correct fake-ack values
								 */
	} else {
		tpcb->tp_netservice = (dom== AF_INET)?IN_CLNS:ISO_CLNS;
		/* the default */
	}
	tpcb->_tp_param = tp_conn_param[tpcb->tp_netservice];

	tpcb->tp_state = TP_CLOSED;
	tpcb->tp_vers  = TP_VERSION;
	tpcb->tp_notdetached = 1;

		   /* Spec says default is 128 octets,
			* that is, if the tpdusize argument never appears, use 128.
			* As the initiator, we will always "propose" the 2048
			* size, that is, we will put this argument in the CR 
			* always, but accept what the other side sends on the CC.
			* If the initiator sends us something larger on a CR,
			* we'll respond w/ this.
			* Our maximum is 4096.  See tp_chksum.c comments.
			*/
	tpcb->tp_cong_win = 
		tpcb->tp_l_tpdusize = 1 << tpcb->tp_tpdusize;

	tpcb->tp_seqmask  = TP_NML_FMT_MASK;
	tpcb->tp_seqbit  =  TP_NML_FMT_BIT;
	tpcb->tp_seqhalf  =  tpcb->tp_seqbit >> 1;

	/* attach to a network-layer protoswitch */
	if ( error =  tp_set_npcb(tpcb))
		goto bad4;
	ASSERT( tpcb->tp_nlproto->nlp_afamily == tpcb->tp_domain);

	/* nothing to do for iso case */
	if( dom == AF_INET )
		sotoinpcb(so)->inp_ppcb = (caddr_t) tpcb;

	return 0;

bad4:
	IFDEBUG(D_CONN)
		printf("BAD4 in tp_attach, so 0x%x\n", so);
	ENDDEBUG
	tp_freeref(tpcb->tp_lref);

bad3:
	IFDEBUG(D_CONN)
		printf("BAD3 in tp_attach, so 0x%x\n", so);
	ENDDEBUG

	free((caddr_t)tpcb, M_PCB); /* never a cluster  */

bad2:
	IFDEBUG(D_CONN)
		printf("BAD2 in tp_attach, so 0x%x\n", so);
	ENDDEBUG
	so->so_pcb = 0;

/*bad:*/
	IFDEBUG(D_CONN)
		printf("BAD in tp_attach, so 0x%x\n", so);
	ENDDEBUG
	return error;
}

/*
 * NAME:  tp_detach()
 *
 * CALLED FROM:
 *	tp.trans, on behalf of a user close request
 *  and when the reference timer goes off
 * (if the disconnect  was initiated by the protocol entity 
 * rather than by the user)
 *
 * FUNCTION and ARGUMENTS:
 *  remove the tpcb structure from the list of active or
 *  partially active connections, recycle all the mbufs
 *  associated with the pcb, ref structure, sockbufs, etc.
 *  Only free the ref structure if you know that a ref timer
 *  wasn't set for this tpcb.
 *
 * RETURNS:  Nada
 *
 * SIDE EFFECTS:
 *
 * NOTES:
 *  tp_soisdisconnected() was already when this is called
 */
void
tp_detach(tpcb)
	register struct tp_pcb 	*tpcb;
{
	void					tp_freeref(), tp_rsyflush();
	register struct socket	 *so = tpcb->tp_sock;

	IFDEBUG(D_CONN)
		printf("tp_detach(tpcb 0x%x, so 0x%x)\n",
			tpcb,so);
	ENDDEBUG
	IFTRACE(D_CONN)
		tptraceTPCB(TPPTmisc, "tp_detach tpcb so lsufx", 
			tpcb, so, *(u_short *)(tpcb->tp_lsuffix), 0);
	ENDTRACE

	IFDEBUG(D_CONN)
		printf("so_snd at 0x%x so_rcv at 0x%x\n", &so->so_snd, &so->so_rcv);
		dump_mbuf(so->so_snd.sb_mb, "so_snd at detach ");
		printf("about to call LL detach, nlproto 0x%x, nl_detach 0x%x\n",
				tpcb->tp_nlproto, tpcb->tp_nlproto->nlp_pcbdetach);
	ENDDEBUG

	if (tpcb->tp_Xsnd.sb_mb) {
		printf("Unsent Xdata on detach; would panic");
		sbflush(&tpcb->tp_Xsnd);
	}
	if (tpcb->tp_ucddata)
		m_freem(tpcb->tp_ucddata);

	IFDEBUG(D_CONN)
		printf("reassembly info cnt %d rsyq 0x%x\n",
		    tpcb->tp_rsycnt, tpcb->tp_rsyq);
	ENDDEBUG
	if (tpcb->tp_rsyq)
		tp_rsyflush(tpcb);

	if (tpcb->tp_next) {
		remque(tpcb);
		tpcb->tp_next = tpcb->tp_prev = 0;
	}
	tpcb->tp_notdetached = 0;

	IFDEBUG(D_CONN)
		printf("calling (...nlproto->...)(0x%x, so 0x%x)\n", 
			tpcb->tp_npcb, so);
		printf("so 0x%x so_head 0x%x,  qlen %d q0len %d qlimit %d\n", 
		so,  so->so_head,
		so->so_q0len, so->so_qlen, so->so_qlimit);
	ENDDEBUG

	(tpcb->tp_nlproto->nlp_pcbdetach)(tpcb->tp_npcb);
				/* does an so->so_pcb = 0; sofree(so) */

	IFDEBUG(D_CONN)
		printf("after xxx_pcbdetach\n");
	ENDDEBUG

	if (tpcb->tp_state == TP_LISTENING) {
		register struct tp_pcb **tt;
		for (tt = &tp_listeners; *tt; tt = &((*tt)->tp_nextlisten))
			if (*tt == tpcb)
				break;
		if (*tt)
			*tt = tpcb->tp_nextlisten;
		else
			printf("tp_detach from listen: should panic\n");
	}
	if (tpcb->tp_refstate == REF_OPENING ) {
		/* no connection existed here so no reference timer will be called */
		IFDEBUG(D_CONN)
			printf("SETTING ref %d to REF_FREE\n", tpcb->tp_lref);
		ENDDEBUG

		tp_freeref(tpcb->tp_lref);
	}
#ifdef TP_PERF_MEAS
	/* 
	 * Get rid of the cluster mbuf allocated for performance measurements, if
	 * there is one.  Note that tpcb->tp_perf_on says nothing about whether or 
	 * not a cluster mbuf was allocated, so you have to check for a pointer 
	 * to one (that is, we need the TP_PERF_MEASs around the following section 
	 * of code, not the IFPERFs)
	 */
	if (tpcb->tp_p_mbuf) {
		register struct mbuf *m = tpcb->tp_p_mbuf;
		struct mbuf *n;
		IFDEBUG(D_PERF_MEAS)
			printf("freeing tp_p_meas 0x%x  ", tpcb->tp_p_meas);
		ENDDEBUG
		do {
		    MFREE(m, n);
		    m = n;
		} while (n);
		tpcb->tp_p_meas = 0;
		tpcb->tp_p_mbuf = 0;
	}
#endif /* TP_PERF_MEAS */

	IFDEBUG(D_CONN)
		printf( "end of detach, NOT single, tpcb 0x%x\n", tpcb);
	ENDDEBUG
	/* free((caddr_t)tpcb, M_PCB); WHere to put this ? */
}

struct que {
	struct tp_pcb *next;
	struct tp_pcb *prev;
} tp_bound_pcbs =
{(struct tp_pcb *)&tp_bound_pcbs, (struct tp_pcb *)&tp_bound_pcbs};

u_short tp_unique;

tp_tselinuse(tlen, tsel, siso, reuseaddr)
caddr_t tsel;
register struct sockaddr_iso *siso;
{
	struct tp_pcb *b = tp_bound_pcbs.next, *l = tp_listeners;
	register struct tp_pcb *t;

	for (;;) {
		if (b != (struct tp_pcb *)&tp_bound_pcbs) {
			t = b; b = t->tp_next;
		} else if (l) {
			t = l; l = t->tp_nextlisten;
		} else
			break;
		if (tlen == t->tp_lsuffixlen && bcmp(tsel, t->tp_lsuffix, tlen) == 0) {
			if (t->tp_flags & TPF_GENERAL_ADDR) {
				if (siso == 0 || reuseaddr == 0)
					return 1;
			} else if (siso) {
				if (siso->siso_family == t->tp_domain &&
					t->tp_nlproto->nlp_cmpnetaddr(t->tp_npcb, siso, TP_LOCAL))
						return 1;
			} else if (reuseaddr == 0)
						return 1;
		}
	}
	return 0;

}


tp_pcbbind(tpcb, nam)
register struct tp_pcb *tpcb;
register struct mbuf *nam;
{
	register struct sockaddr_iso *siso = 0;
	int tlen = 0, wrapped = 0;
	caddr_t tsel;
	u_short tutil;

	if (tpcb->tp_state != TP_CLOSED)
		return (EINVAL);
	if (nam) {
		siso = mtod(nam, struct sockaddr_iso *);
		switch (siso->siso_family) {
		default:
			return (EAFNOSUPPORT);
#ifdef ISO
		case AF_ISO:
			tlen = siso->siso_tlen;
			tsel = TSEL(siso);
			if (siso->siso_nlen == 0)
				siso = 0;
			break;
#endif
#ifdef INET
		case AF_INET:
			tsel = (caddr_t)&tutil;
			if (tutil =  ((struct sockaddr_in *)siso)->sin_port) {
				tlen = 2;
			}
			if (((struct sockaddr_in *)siso)->sin_addr.s_addr == 0)
				siso = 0;
		}
#endif
	}
	if (tpcb->tp_lsuffixlen == 0) {
		if (tlen) {
			if (tp_tselinuse(tlen, tsel, siso,
								tpcb->tp_sock->so_options & SO_REUSEADDR))
				return (EINVAL);
		} else {
			for (tsel = (caddr_t)&tutil, tlen = 2;;){
				if (tp_unique++ < ISO_PORT_RESERVED ||
					tp_unique > ISO_PORT_USERRESERVED) {
						if (wrapped++)
							return ESRCH;
						tp_unique = ISO_PORT_RESERVED;
				}
				tutil = htons(tp_unique);
				if (tp_tselinuse(tlen, tsel, siso, 0) == 0)
					break;
			}
			if (siso) switch (siso->siso_family) {
#ifdef ISO
				case AF_ISO:
					bcopy(tsel, TSEL(siso), tlen);
					siso->siso_tlen = tlen;
					break;
#endif
#ifdef INET
				case AF_INET:
					((struct sockaddr_in *)siso)->sin_port = tutil;
#endif
				}
		}
		bcopy(tsel, tpcb->tp_lsuffix, (tpcb->tp_lsuffixlen = tlen));
		insque(tpcb, &tp_bound_pcbs);
	} else {
		if (tlen || siso == 0)
			return (EINVAL);
	}
	if (siso == 0) {
		tpcb->tp_flags |= TPF_GENERAL_ADDR;
		return (0);
	}
	return tpcb->tp_nlproto->nlp_pcbbind(tpcb->tp_npcb, nam);
}