rtsock.c

很好的一个嵌入式linux平台下的bootloader

flush:
	if (rtm) {
		if (error)
			rtm->rtm_errno = error;
		else 
			rtm->rtm_flags |= RTF_DONE;
	}
cleanup:
	if (rt)
		rtfree(rt);
    {
	register struct rawcb *rp = 0;
	/*
	 * Check to see if we don't want our own messages.
	 */
	if ((so->so_options & SO_USELOOPBACK) == 0) {
		if (route_cb.any_count <= 1) {
			if (rtm)
				Free(rtm);
			m_freem(m);
			return (error);
		}
		/* There is another listener, so construct message */
		rp = sotorawcb(so);
	}
	if (rtm) {
		m_copyback(m, 0, rtm->rtm_msglen, (caddr_t)rtm);
		Free(rtm);
	}
	if (rp)
		rp->rcb_proto.sp_family = 0; /* Avoid us */
	if (dst)
		route_proto.sp_protocol = dst->sa_family;
	route_proto.sp_family = PF_ROUTE;
	raw_input(m, &route_proto, &route_src, &route_dst);
	if (rp)
		rp->rcb_proto.sp_family = PF_ROUTE;
    }
	return (error);
}

rt_setmetrics(which, in, out)
	u_long which;
	register struct rt_metrics *in, *out;
{
#define metric(f, e) if (which & (f)) out->e = in->e;
	metric(RTV_RPIPE, rmx_recvpipe);
	metric(RTV_SPIPE, rmx_sendpipe);
	metric(RTV_SSTHRESH, rmx_ssthresh);
	metric(RTV_RTT, rmx_rtt);
	metric(RTV_RTTVAR, rmx_rttvar);
	metric(RTV_HOPCOUNT, rmx_hopcount);
	metric(RTV_MTU, rmx_mtu);
	metric(RTV_EXPIRE, rmx_expire);
#undef metric
}

/*
 * Copy data from a buffer back into the indicated mbuf chain,
 * starting "off" bytes from the beginning, extending the mbuf
 * chain if necessary.
 */
m_copyback(m0, off, len, cp)
	struct	mbuf *m0;
	register int off;
	register int len;
	caddr_t cp;

{
	register int mlen;
	register struct mbuf *m = m0, *n;
	int totlen = 0;

	if (m0 == 0)
		return;
	while (off > (mlen = m->m_len)) {
		off -= mlen;
		totlen += mlen;
		if (m->m_next == 0) {
			n = m_getclr(M_DONTWAIT, m->m_type);
			if (n == 0)
				goto out;
			n->m_len = min(MLEN, len + off);
			m->m_next = n;
		}
		m = m->m_next;
	}
	while (len > 0) {
		mlen = min (m->m_len - off, len);
		bcopy(cp, off + mtod(m, caddr_t), (unsigned)mlen);
		cp += mlen;
		len -= mlen;
		mlen += off;
		off = 0;
		totlen += mlen;
		if (len == 0)
			break;
		if (m->m_next == 0) {
			n = m_get(M_DONTWAIT, m->m_type);
			if (n == 0)
				break;
			n->m_len = min(MLEN, len);
			m->m_next = n;
		}
		m = m->m_next;
	}
out:	if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen))
		m->m_pkthdr.len = totlen;
}

/* 
 * The miss message and losing message are very similar.
 */

rt_missmsg(type, dst, gate, mask, src, flags, error)
register struct sockaddr *dst;
struct sockaddr *gate, *mask, *src;
{
	register struct rt_msghdr *rtm;
	register struct mbuf *m;
	int dlen = ROUNDUP(dst->sa_len);
	int len = dlen + sizeof(*rtm);

	if (route_cb.any_count == 0)
		return;
	m = m_gethdr(M_DONTWAIT, MT_DATA);
	if (m == 0)
		return;
	m->m_pkthdr.len = m->m_len = min(len, MHLEN);
	m->m_pkthdr.rcvif = 0;
	rtm = mtod(m, struct rt_msghdr *);
	bzero((caddr_t)rtm, sizeof(*rtm)); /*XXX assumes sizeof(*rtm) < MHLEN*/
	rtm->rtm_flags = RTF_DONE | flags;
	rtm->rtm_msglen = len;
	rtm->rtm_version = RTM_VERSION;
	rtm->rtm_type = type;
	rtm->rtm_addrs = RTA_DST;
	if (type == RTM_OLDADD || type == RTM_OLDDEL) {
		rtm->rtm_pid = curproc->p_pid;
	}
	m_copyback(m, sizeof (*rtm), dlen, (caddr_t)dst);
	if (gate) {
		dlen = ROUNDUP(gate->sa_len);
		m_copyback(m, len ,  dlen, (caddr_t)gate);
		len += dlen;
		rtm->rtm_addrs |= RTA_GATEWAY;
	}
	if (mask) {
		dlen = ROUNDUP(mask->sa_len);
		m_copyback(m, len ,  dlen, (caddr_t)mask);
		len += dlen;
		rtm->rtm_addrs |= RTA_NETMASK;
	}
	if (src) {
		dlen = ROUNDUP(src->sa_len);
		m_copyback(m, len ,  dlen, (caddr_t)src);
		len += dlen;
		rtm->rtm_addrs |= RTA_AUTHOR;
	}
	if (m->m_pkthdr.len != len) {
		m_freem(m);
		return;
	}
	rtm->rtm_errno = error;
	rtm->rtm_msglen = len;
	route_proto.sp_family = PF_ROUTE;
	route_proto.sp_protocol = dst->sa_family;
	raw_input(m, &route_proto, &route_src, &route_dst);
}

#ifndef PROM
#include "kinfo.h"
struct walkarg {
	int	w_op, w_arg;
	int	w_given, w_needed;
	caddr_t	w_where;
	struct	{
		struct rt_msghdr m_rtm;
		char	m_sabuf[128];
	} w_m;
#define w_rtm w_m.m_rtm
};
/*
 * This is used in dumping the kernel table via getkinfo().
 */
rt_dumpentry(rn, w)
	struct radix_node *rn;
	register struct walkarg *w;
{
	register struct sockaddr *sa;
	int n, error;

    for (; rn; rn = rn->rn_dupedkey) {
	int count = 0, size = sizeof(w->w_rtm);
	register struct rtentry *rt = (struct rtentry *)rn;

	if (rn->rn_flags & RNF_ROOT)
		continue;
	if (w->w_op == KINFO_RT_FLAGS && !(rt->rt_flags & w->w_arg))
		continue;
#define next(a, l) {size += (l); w->w_rtm.rtm_addrs |= (a); }
	w->w_rtm.rtm_addrs = 0;
	if (sa = rt_key(rt))
		next(RTA_DST, ROUNDUP(sa->sa_len));
	if (sa = rt->rt_gateway)
		next(RTA_GATEWAY, ROUNDUP(sa->sa_len));
	if (sa = rt_mask(rt))
		next(RTA_NETMASK, ROUNDUP(sa->sa_len));
	if (sa = rt->rt_genmask)
		next(RTA_GENMASK, ROUNDUP(sa->sa_len));
	w->w_needed += size;
	if (w->w_where == NULL || w->w_needed > 0)
		continue;
	w->w_rtm.rtm_msglen = size;
	w->w_rtm.rtm_flags = rt->rt_flags;
	w->w_rtm.rtm_use = rt->rt_use;
	w->w_rtm.rtm_rmx = rt->rt_rmx;
	w->w_rtm.rtm_index = rt->rt_ifp->if_index;
#undef next
#define next(l) {n = (l); Bcopy(sa, cp, n); cp += n;}
	if (size <= sizeof(w->w_m)) {
		register caddr_t cp = (caddr_t)(w->w_m.m_sabuf);
		if (sa = rt_key(rt))
			next(ROUNDUP(sa->sa_len));
		if (sa = rt->rt_gateway)
			next(ROUNDUP(sa->sa_len));
		if (sa = rt_mask(rt))
			next(ROUNDUP(sa->sa_len));
		if (sa = rt->rt_genmask)
			next(ROUNDUP(sa->sa_len));
#undef next
#define next(s, l) {n = (l); \
    if (error = copyout((caddr_t)(s), w->w_where, n)) return (error); \
    w->w_where += n;}

		next(&w->w_m, size); /* Copy rtmsg and sockaddrs back */
		continue;
	}
	next(&w->w_rtm, sizeof(w->w_rtm));
	if (sa = rt_key(rt))
		next(sa, ROUNDUP(sa->sa_len));
	if (sa = rt->rt_gateway)
		next(sa, ROUNDUP(sa->sa_len));
	if (sa = rt_mask(rt))
		next(sa, ROUNDUP(sa->sa_len));
	if (sa = rt->rt_genmask)
		next(sa, ROUNDUP(sa->sa_len));
    }
	return (0);
#undef next
}

kinfo_rtable(op, where, given, arg, needed)
	int	op, arg;
	caddr_t	where;
	int	*given, *needed;
{
	register struct radix_node_head *rnh;
	int	s, error = 0;
	u_char  af = ki_af(op);
	struct	walkarg w;

	op &= 0xffff;
	if (op != KINFO_RT_DUMP && op != KINFO_RT_FLAGS)
		return (EINVAL);

	Bzero(&w, sizeof(w));
	if ((w.w_where = where) && given)
		w.w_given = *given;
	w.w_needed = 0 - w.w_given;
	w.w_arg = arg;
	w.w_op = op;
	w.w_rtm.rtm_version = RTM_VERSION;
	w.w_rtm.rtm_type = RTM_GET;

	s = splnet();
	for (rnh = radix_node_head; rnh; rnh = rnh->rnh_next) {
		if (rnh->rnh_af == 0)
			continue;
		if (af && af != rnh->rnh_af)
			continue;
		error = rt_walk(rnh->rnh_treetop, rt_dumpentry, &w);
		if (error)
			break;
	}
	w.w_needed += w.w_given;
	if (where && given)
		*given = w.w_where - where;
	else
		w.w_needed = (11 * w.w_needed) / 10;
	*needed = w.w_needed;
	splx(s);
	return (error);
}

rt_walk(rn, f, w)
	register struct radix_node *rn;
	register int (*f)();
	struct walkarg *w;
{
	int error;
	for (;;) {
		while (rn->rn_b >= 0)
			rn = rn->rn_l;	/* First time through node, go left */
		if (error = (*f)(rn, w))
			return (error);	/* Process Leaf */
		while (rn->rn_p->rn_r == rn) {	/* if coming back from right */
			rn = rn->rn_p;		/* go back up */
			if (rn->rn_flags & RNF_ROOT)
				return 0;
		}
		rn = rn->rn_p->rn_r;		/* otherwise, go right*/
	}
}
#endif /* !PROM */

/*
 * Definitions of protocols supported in the ROUTE domain.
 */

int	route_init(),raw_usrreq(),raw_input(),raw_ctlinput();
extern	struct domain routedomain;		/* or at least forward */

const struct protosw routesw[] = {
{ SOCK_RAW,	&routedomain,	0,		PR_ATOMIC|PR_ADDR,
  raw_input,	route_output,	raw_ctlinput,	0,
  route_usrreq,
  route_init,	0,		0,		0,
}
};

int	unp_externalize(), unp_dispose();

#ifdef NO_DATA
#define CONST const
#else
#define CONST 
#endif

CONST struct domain routedomain =
    { PF_ROUTE, "route", 0, 0, 0,
      routesw, &routesw[sizeof(routesw)/sizeof(routesw[0])] };