if_x25subr.c

早期freebsd实现

		     --lcpp > pkcb->pk_chan;)
			if ((lcp = *lcpp) &&
			    lcp->lcd_state == DATA_TRANSFER &&
			    (lcp->lcd_flags & X25_DG_CIRCUIT) &&
			    (lcp->lcd_dg_timer && --lcp->lcd_dg_timer == 0)) {
				lcp->lcd_upper(lcp, 0);
			}
	splx(s);
}
/*
 * This routine gets called when validating additions of new routes
 * or deletions of old ones.
 */
x25_rtrequest(cmd, rt, dst)
register struct rtentry *rt;
struct sockaddr *dst;
{
	register struct llinfo_x25 *lx = (struct llinfo_x25 *)rt->rt_llinfo;
	register struct sockaddr_x25 *sa =(struct sockaddr_x25 *)rt->rt_gateway;
	register struct pklcd *lcp;

	/* would put this pk_init, except routing table doesn't
	   exist yet. */
	if (x25_dgram_sockmask == 0) {
		struct radix_node *rn_addmask();
		x25_dgram_sockmask =
			SA(rn_addmask((caddr_t)&x25_dgmask, 0, 4)->rn_key);
	}
	if (rt->rt_flags & RTF_GATEWAY) {
		if (rt->rt_llinfo)
			RTFREE((struct rtentry *)rt->rt_llinfo);
		rt->rt_llinfo = (cmd == RTM_ADD) ? 
			(caddr_t)rtalloc1(rt->rt_gateway, 1) : 0;
		return;
	}
	if ((rt->rt_flags & RTF_HOST) == 0)
		return;
	if (cmd == RTM_DELETE) {
		while (rt->rt_llinfo)
			x25_lxfree((struct llinfo *)rt->rt_llinfo);
		x25_rtinvert(RTM_DELETE, rt->rt_gateway, rt);
		return;
	}
	if (lx == 0 && (lx = x25_lxalloc(rt)) == 0)
		return;
	if ((lcp = lx->lx_lcd) && lcp->lcd_state != READY) {
		/*
		 * This can only happen on a RTM_CHANGE operation
		 * though cmd will be RTM_ADD.
		 */
		if (lcp->lcd_ceaddr &&
		    Bcmp(rt->rt_gateway, lcp->lcd_ceaddr,
					 lcp->lcd_ceaddr->x25_len) != 0) {
			x25_rtinvert(RTM_DELETE, lcp->lcd_ceaddr, rt);
			lcp->lcd_upper = 0;
			pk_disconnect(lcp);
		}
		lcp = 0;
	}
	x25_rtinvert(RTM_ADD, rt->rt_gateway, rt);
}

int x25_dont_rtinvert = 0;

x25_rtinvert(cmd, sa, rt)
register struct sockaddr *sa;
register struct rtentry *rt;
{
	struct rtentry *rt2 = 0;
	/*
	 * rt_gateway contains PID indicating which proto
	 * family on the other end, so will be different
	 * from general host route via X.25.
	 */
	if (rt->rt_ifp->if_type == IFT_X25DDN || x25_dont_rtinvert)
		return;
	if (sa->sa_family != AF_CCITT)
		return;
	if (cmd != RTM_DELETE) {
		rtrequest(RTM_ADD, sa, rt_key(rt), x25_dgram_sockmask,
				RTF_PROTO2, &rt2);
		if (rt2) {
			rt2->rt_llinfo = (caddr_t) rt;
			rt->rt_refcnt++;
		}
		return;
	}
	rt2 = rt;
	if ((rt = rtalloc1(sa, 0)) == 0 ||
	    (rt->rt_flags & RTF_PROTO2) == 0 ||
	    rt->rt_llinfo != (caddr_t)rt2) {
		printf("x25_rtchange: inverse route screwup\n");
		return;
	} else
		rt2->rt_refcnt--;
	rtrequest(RTM_DELETE, sa, rt_key(rt2), x25_dgram_sockmask,
				0, (struct rtentry **) 0);
}

static struct sockaddr_x25 blank_x25 = {sizeof blank_x25, AF_CCITT};
/*
 * IP to X25 address routine copyright ACC, used by permission.
 */
union imp_addr {
	struct in_addr  ip;
	struct imp {
		u_char		s_net;
		u_char		s_host;
		u_char		s_lh;
		u_char		s_impno;
	}		    imp;
};

/*
 * The following is totally bogus and here only to preserve
 * the IP to X.25 translation.
 */
x25_ddnip_to_ccitt(src, rt)
struct sockaddr_in *src;
register struct rtentry *rt;
{
	register struct sockaddr_x25 *dst = (struct sockaddr_x25 *)rt->rt_gateway;
	union imp_addr imp_addr;
	int             imp_no, imp_port, temp;
	char *x25addr = dst->x25_addr;


	imp_addr.ip = src->sin_addr;
	*dst = blank_x25;
	if ((imp_addr.imp.s_net & 0x80) == 0x00) {	/* class A */
	    imp_no = imp_addr.imp.s_impno;
	    imp_port = imp_addr.imp.s_host;
	} else if ((imp_addr.imp.s_net & 0xc0) == 0x80) {	/* class B */
	    imp_no = imp_addr.imp.s_impno;
	    imp_port = imp_addr.imp.s_lh;
	} else {		/* class C */
	    imp_no = imp_addr.imp.s_impno / 32;
	    imp_port = imp_addr.imp.s_impno % 32;
	}

	x25addr[0] = 12; /* length */
	/* DNIC is cleared by struct copy above */

	if (imp_port < 64) {	/* Physical:  0000 0 IIIHH00 [SS] *//* s_impno
				 *  -> III, s_host -> HH */
	    x25addr[5] = 0;	/* set flag bit */
	    x25addr[6] = imp_no / 100;
	    x25addr[7] = (imp_no % 100) / 10;
	    x25addr[8] = imp_no % 10;
	    x25addr[9] = imp_port / 10;
	    x25addr[10] = imp_port % 10;
	} else {		/* Logical:   0000 1 RRRRR00 [SS]	 *//* s
				 * _host * 256 + s_impno -> RRRRR */
	    temp = (imp_port << 8) + imp_no;
	    x25addr[5] = 1;
	    x25addr[6] = temp / 10000;
	    x25addr[7] = (temp % 10000) / 1000;
	    x25addr[8] = (temp % 1000) / 100;
	    x25addr[9] = (temp % 100) / 10;
	    x25addr[10] = temp % 10;
	}
}

/*
 * This routine is a sketch and is not to be believed!!!!!
 *
 * This is a utility routine to be called by x25 devices when a
 * call request is honored with the intent of starting datagram forwarding.
 */
x25_dg_rtinit(dst, ia, af)
struct sockaddr_x25 *dst;
register struct x25_ifaddr *ia;
{
	struct sockaddr *sa = 0;
	struct rtentry *rt;
	struct in_addr my_addr;
	static struct sockaddr_in sin = {sizeof(sin), AF_INET};

	if (ia->ia_ifp->if_type == IFT_X25DDN && af == AF_INET) {
	/*
	 * Inverse X25 to IP mapping copyright and courtesy ACC.
	 */
		int             imp_no, imp_port, temp;
		union imp_addr imp_addr;
	    {
		/*
		 * First determine our IP addr for network
		 */
		register struct in_ifaddr *ina;
		extern struct in_ifaddr *in_ifaddr;

		for (ina = in_ifaddr; ina; ina = ina->ia_next)
			if (ina->ia_ifp == ia->ia_ifp) {
				my_addr = ina->ia_addr.sin_addr;
				break;
			}
	    }
	    {

		register char *x25addr = dst->x25_addr;

		switch (x25addr[5] & 0x0f) {
		  case 0:	/* Physical:  0000 0 IIIHH00 [SS]	 */
		    imp_no =
			((int) (x25addr[6] & 0x0f) * 100) +
			((int) (x25addr[7] & 0x0f) * 10) +
			((int) (x25addr[8] & 0x0f));


		    imp_port =
			((int) (x25addr[9] & 0x0f) * 10) +
			((int) (x25addr[10] & 0x0f));
		    break;
		  case 1:	/* Logical:   0000 1 RRRRR00 [SS]	 */
		    temp = ((int) (x25addr[6] & 0x0f) * 10000)
			+ ((int) (x25addr[7] & 0x0f) * 1000)
			+ ((int) (x25addr[8] & 0x0f) * 100)
			+ ((int) (x25addr[9] & 0x0f) * 10)
			+ ((int) (x25addr[10] & 0x0f));

		    imp_port = temp >> 8;
		    imp_no = temp & 0xff;
		    break;
		  default:
		    return (0L);
		}
		imp_addr.ip = my_addr;
		if ((imp_addr.imp.s_net & 0x80) == 0x00) {
		/* class A */
		    imp_addr.imp.s_host = imp_port;
		    imp_addr.imp.s_impno = imp_no;
		    imp_addr.imp.s_lh = 0;
		} else if ((imp_addr.imp.s_net & 0xc0) == 0x80) {
		/* class B */
		    imp_addr.imp.s_lh = imp_port;
		    imp_addr.imp.s_impno = imp_no;
		} else {
		/* class C */
		    imp_addr.imp.s_impno = (imp_no << 5) + imp_port;
		}
	    }
		sin.sin_addr = imp_addr.ip;
		sa = (struct sockaddr *)&sin;
	} else {
		/*
		 * This uses the X25 routing table to do inverse
		 * lookup of x25 address to sockaddr.
		 */
		if (rt = rtalloc1(SA(dst), 0)) {
			sa = rt->rt_gateway;
			rt->rt_refcnt--;
		}
	}
	/* 
	 * Call to rtalloc1 will create rtentry for reverse path
	 * to callee by virtue of cloning magic and will allocate
	 * space for local control block.
	 */
	if (sa && (rt = rtalloc1(sa, 1)))
		rt->rt_refcnt--;
}
int x25_startproto = 1;

pk_init()
{
	/*
	 * warning, sizeof (struct sockaddr_x25) > 32,
	 * but contains no data of interest beyond 32
	 */
	if (x25_startproto) {
		pk_protolisten(0xcc, 1, x25_dgram_incoming);
		pk_protolisten(0x81, 1, x25_dgram_incoming);
	}
}

struct x25_dgproto {
	u_char spi;
	u_char spilen;
	int (*f)();
} x25_dgprototab[] = {
#if defined(ISO) && defined(TPCONS)
{ 0x0, 0, tp_incoming},
#endif
{ 0xcc, 1, x25_dgram_incoming},
{ 0xcd, 1, x25_dgram_incoming},
{ 0x81, 1, x25_dgram_incoming},
};

pk_user_protolisten(info)
register u_char *info;
{
	register struct x25_dgproto *dp = x25_dgprototab
		    + ((sizeof x25_dgprototab) / (sizeof *dp));
	register struct pklcd *lcp;
	
	while (dp > x25_dgprototab)
		if ((--dp)->spi == info[0])
			goto gotspi;
	return ESRCH;

gotspi:	if (info[1])
		return pk_protolisten(dp->spi, dp->spilen, dp->f);
	for (lcp = pk_listenhead; lcp; lcp = lcp->lcd_listen)
		if (lcp->lcd_laddr.x25_udlen == dp->spilen &&
		    Bcmp(&dp->spi, lcp->lcd_laddr.x25_udata, dp->spilen) == 0) {
			pk_disconnect(lcp);
			return 0;
		}
	return ESRCH;
}

/*
 * This routine transfers an X.25 circuit to or from a routing entry.
 * If the supplied circuit is * in DATA_TRANSFER state, it is added to the
 * routing entry.  If freshly allocated, it glues back the vc from
 * the rtentry to the socket.
 */
pk_rtattach(so, m0)
register struct socket *so;
struct mbuf *m0;
{
	register struct pklcd *lcp = (struct pklcd *)so->so_pcb;
	register struct mbuf *m = m0;
	struct sockaddr *dst = mtod(m, struct sockaddr *);
	register struct rtentry *rt = rtalloc1(dst, 0);
	register struct llinfo_x25 *lx;
	caddr_t cp;
#define ROUNDUP(a) \
	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
#define transfer_sockbuf(s, f, l) \
	while (m = (s)->sb_mb)\
		{(s)->sb_mb = m->m_act; m->m_act = 0; sbfree((s), m); f(l, m);}

	if (rt)
		rt->rt_refcnt--;
	cp = (dst->sa_len < m->m_len) ? ROUNDUP(dst->sa_len) + (caddr_t)dst : 0;
	while (rt &&
	       ((cp == 0 && rt_mask(rt) != 0) ||
		(cp != 0 && (rt_mask(rt) == 0 ||
			     Bcmp(cp, rt_mask(rt), rt_mask(rt)->sa_len)) != 0)))
			rt = (struct rtentry *)rt->rt_nodes->rn_dupedkey;
	if (rt == 0 || (rt->rt_flags & RTF_GATEWAY) ||
	    (lx = (struct llinfo_x25 *)rt->rt_llinfo) == 0)
		return ESRCH;
	if (lcp == 0)
		return ENOTCONN;
	switch (lcp->lcd_state) {
	default:
		return ENOTCONN;

	case READY:
		/* Detach VC from rtentry */
		if (lx->lx_lcd == 0)
			return ENOTCONN;
		lcp->lcd_so = 0;
		pk_close(lcp);
		lcp = lx->lx_lcd;
		if (lx->lx_next->lx_rt == rt)
			x25_lxfree(lx);
		lcp->lcd_so = so;
		lcp->lcd_upper = 0;
		lcp->lcd_upnext = 0;
		transfer_sockbuf(&lcp->lcd_sb, sbappendrecord, &so->so_snd);
		soisconnected(so);
		return 0;

	case DATA_TRANSFER:
		/* Add VC to rtentry */
		lcp->lcd_so = 0;
		lcp->lcd_sb = so->so_snd; /* structure copy */
		bzero((caddr_t)&so->so_snd, sizeof(so->so_snd)); /* XXXXXX */
		so->so_pcb = 0;
		x25_rtattach(lcp, rt);
		transfer_sockbuf(&so->so_rcv, x25_ifinput, lcp);
		soisdisconnected(so);
	}
	return 0;
}
x25_rtattach(lcp0, rt)
register struct pklcd *lcp0;
struct rtentry *rt;
{
	register struct llinfo_x25 *lx = (struct llinfo_x25 *)rt->rt_llinfo;
	register struct pklcd *lcp;
	register struct mbuf *m;
	if (lcp = lx->lx_lcd) { /* adding an additional VC */
		if (lcp->lcd_state == READY) {
			transfer_sockbuf(&lcp->lcd_sb, pk_output, lcp0);
			lcp->lcd_upper = 0;
			pk_close(lcp);
		} else {
			lx = x25_lxalloc(rt);
			if (lx == 0)
				return ENOBUFS;
		}
	}
	lx->lx_lcd = lcp = lcp0;
	lcp->lcd_upper = x25_ifinput;
	lcp->lcd_upnext = (caddr_t)lx;
}