X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/a9f3e17433e07b2aa0bc51e8194a7fd7952fe44f..274c3d56636e19a3069b6b5263a9f5e7affe53ea:/usr/src/sys/net/route.c

diff --git a/usr/src/sys/net/route.c b/usr/src/sys/net/route.c
index f9b9e232e5..9b44703256 100644
--- a/usr/src/sys/net/route.c
+++ b/usr/src/sys/net/route.c
@@ -1,64 +1,86 @@
-/*	route.c	4.6	82/03/31	*/
+/*	route.c	6.1	83/07/29	*/
 
 #include "../h/param.h"
 #include "../h/systm.h"
 #include "../h/mbuf.h"
 #include "../h/protosw.h"
 #include "../h/socket.h"
+#include "../h/dir.h"
+#include "../h/user.h"
 #include "../h/ioctl.h"
-#include "../net/in.h"
-#include "../net/in_systm.h"
+#include "../h/errno.h"
+
 #include "../net/if.h"
 #include "../net/af.h"
 #include "../net/route.h"
-#include <errno.h>
+
+int	rttrash;		/* routes not in table but not freed */
+struct	sockaddr wildcard;	/* zero valued cookie for wildcard searches */
 
 /*
  * Packet routing routines.
  */
-
 rtalloc(ro)
 	register struct route *ro;
 {
-	register struct rtentry *rt, *rtmin;
+	register struct rtentry *rt;
 	register struct mbuf *m;
-	register int hash, (*match)();
-	struct afhash h;
+	register unsigned hash;
 	struct sockaddr *dst = &ro->ro_dst;
-	int af = dst->sa_family;
+	int (*match)(), doinghost;
+	struct afhash h;
+	u_int af = dst->sa_family;
+	struct rtentry *rtmin;
+	struct mbuf **table;
 
-COUNT(RTALLOC);
 	if (ro->ro_rt && ro->ro_rt->rt_ifp)			/* XXX */
 		return;
+	if (af >= AF_MAX)
+		return;
 	(*afswitch[af].af_hash)(dst, &h);
-	rtmin = 0, hash = h.afh_hosthash;
-	for (m = rthost[hash % RTHASHSIZ]; m; m = m->m_next) {
-		rt = mtod(m, struct rtentry *);
-		if (rt->rt_hash != hash)
-			continue;
-		if (bcmp((caddr_t)&rt->rt_dst, (caddr_t)dst, sizeof (*dst)))
-			continue;
-		if (rtmin == 0 || rt->rt_use < rtmin->rt_use)
-			rtmin = rt;
-	}
-	if (rtmin) 
-		goto found;
-
-	hash = h.afh_nethash;
+	rtmin = 0;
 	match = afswitch[af].af_netmatch;
-	for (m = rtnet[hash % RTHASHSIZ]; m; m = m->m_next) {
+	hash = h.afh_hosthash, table = rthost, doinghost = 1;
+again:
+	for (m = table[hash % RTHASHSIZ]; m; m = m->m_next) {
 		rt = mtod(m, struct rtentry *);
 		if (rt->rt_hash != hash)
 			continue;
-		if (rt->rt_dst.sa_family != af || !(*match)(&rt->rt_dst, dst))
+		if ((rt->rt_flags & RTF_UP) == 0 ||
+		    (rt->rt_ifp->if_flags & IFF_UP) == 0)
 			continue;
+		if (doinghost) {
+			if (bcmp((caddr_t)&rt->rt_dst, (caddr_t)dst,
+			    sizeof (*dst)))
+				continue;
+		} else {
+			if (rt->rt_dst.sa_family != af ||
+			    !(*match)(&rt->rt_dst, dst))
+				continue;
+		}
 		if (rtmin == 0 || rt->rt_use < rtmin->rt_use)
 			rtmin = rt;
 	}
-found:
+	if (rtmin == 0 && doinghost) {
+		doinghost = 0;
+		hash = h.afh_nethash, table = rtnet;
+		goto again;
+	}
+	/*
+	 * Check for wildcard gateway, by convention network 0.
+	 */
+	if (rtmin == 0 && dst != &wildcard) {
+		dst = &wildcard, hash = 0;
+		goto again;
+	}
 	ro->ro_rt = rtmin;
-	if (rtmin)
-		rtmin->rt_refcnt++;
+	if (rtmin == 0) {
+		rtstat.rts_unreach++;
+		return;
+	}
+	rtmin->rt_refcnt++;
+	if (dst == &wildcard)
+		rtstat.rts_wildcard++;
 }
 
 rtfree(rt)
@@ -66,115 +88,184 @@ rtfree(rt)
 {
 
 	if (rt == 0)
-		panic("freeroute");
+		panic("rtfree");
 	rt->rt_refcnt--;
-	/* on refcnt == 0 reclaim? notify someone? */
+	if (rt->rt_refcnt == 0 && (rt->rt_flags&RTF_UP) == 0) {
+		rttrash--;
+		(void) m_free(dtom(rt));
+	}
+}
+
+/*
+ * Force a routing table entry to the specified
+ * destination to go through the given gateway.
+ * Normally called as a result of a routing redirect
+ * message from the network layer.
+ *
+ * N.B.: must be called at splnet or higher
+ *
+ * Should notify all parties with a reference to
+ * the route that it's changed (so, for instance,
+ * current round trip time estimates could be flushed),
+ * but we have no back pointers at the moment.
+ */
+rtredirect(dst, gateway)
+	struct sockaddr *dst, *gateway;
+{
+	struct route ro;
+	register struct rtentry *rt;
+
+	/* verify the gateway is directly reachable */
+	if (if_ifwithnet(gateway) == 0) {
+		rtstat.rts_badredirect++;
+		return;
+	}
+	ro.ro_dst = *dst;
+	ro.ro_rt = 0;
+	rtalloc(&ro);
+	rt = ro.ro_rt;
+	/*
+	 * Create a new entry if we just got back a wildcard entry
+	 * or the the lookup failed.  This is necessary for hosts
+	 * which use routing redirects generated by smart gateways
+	 * to dynamically build the routing tables.
+	 */
+	if (rt &&
+	    (*afswitch[dst->sa_family].af_netmatch)(&wildcard, &rt->rt_dst)) {
+		rtfree(rt);
+		rt = 0;
+	}
+	if (rt == 0) {
+		rtinit(dst, gateway, RTF_GATEWAY);
+		rtstat.rts_dynamic++;
+		return;
+	}
+	/*
+	 * Don't listen to the redirect if it's
+	 * for a route to an interface. 
+	 */
+	if (rt->rt_flags & RTF_GATEWAY) {
+		/*
+		 * Smash the current notion of the gateway to
+		 * this destination.  This is probably not right,
+		 * as it's conceivable a flurry of redirects could
+		 * cause the gateway value to fluctuate wildly during
+		 * dynamic routing reconfiguration.
+		 */
+		rt->rt_gateway = *gateway;
+		rtfree(rt);
+		rtstat.rts_newgateway++;
+		return;
+	}
+}
+
+/*
+ * Routing table ioctl interface.
+ */
+rtioctl(cmd, data)
+	int cmd;
+	caddr_t data;
+{
+
+	if (cmd != SIOCADDRT && cmd != SIOCDELRT)
+		return (EINVAL);
+	if (!suser())
+		return (u.u_error);
+	return (rtrequest(cmd, (struct rtentry *)data));
 }
 
-#define	equal(a1, a2) \
-	(bcmp((caddr_t)(a1), (caddr_t)(a2), sizeof (struct sockaddr)) == 0)
 /*
  * Carry out a request to change the routing table.  Called by
- * interfaces at boot time to make their ``local routes'' known
- * and for ioctl's.
+ * interfaces at boot time to make their ``local routes'' known,
+ * for ioctl's, and as the result of routing redirects.
  */
-rtrequest(req, new)
+rtrequest(req, entry)
 	int req;
-	register struct rtentry *new;
+	register struct rtentry *entry;
 {
-	register struct rtentry *rt;
 	register struct mbuf *m, **mprev;
-	register int hash, (*match)();
-	register struct sockaddr *sa = &new->rt_dst;
-	register struct sockaddr *gate = &new->rt_gateway;
+	register struct rtentry *rt;
 	struct afhash h;
-	struct mbuf **oldmprev;
-	int af = sa->sa_family, doinghost, s, error = 0;
-
-COUNT(RTREQUEST);
-	(*afswitch[af].af_hash)(sa, &h);
-	hash = h.afh_hosthash;
-	mprev = &rthost[hash % RTHASHSIZ];
-	doinghost = 1;
+	int s, error = 0, hash, (*match)();
+	u_int af;
+	struct ifnet *ifp;
+
+	af = entry->rt_dst.sa_family;
+	if (af >= AF_MAX)
+		return (EAFNOSUPPORT);
+	(*afswitch[af].af_hash)(&entry->rt_dst, &h);
+	if (entry->rt_flags & RTF_HOST) {
+		hash = h.afh_hosthash;
+		mprev = &rthost[hash % RTHASHSIZ];
+	} else {
+		hash = h.afh_nethash;
+		mprev = &rtnet[hash % RTHASHSIZ];
+	}
+	match = afswitch[af].af_netmatch;
 	s = splimp();
-again:
 	for (; m = *mprev; mprev = &m->m_next) {
 		rt = mtod(m, struct rtentry *);
 		if (rt->rt_hash != hash)
 			continue;
-		if (doinghost) {
-			if (!equal(&rt->rt_dst, sa))
+		if (entry->rt_flags & RTF_HOST) {
+#define	equal(a1, a2) \
+	(bcmp((caddr_t)(a1), (caddr_t)(a2), sizeof (struct sockaddr)) == 0)
+			if (!equal(&rt->rt_dst, &entry->rt_dst))
 				continue;
 		} else {
-			if (rt->rt_dst.sa_family != sa->sa_family ||
-			    (*match)(&rt->rt_dst, sa) == 0)
+			if (rt->rt_dst.sa_family != entry->rt_dst.sa_family ||
+			    (*match)(&rt->rt_dst, &entry->rt_dst) == 0)
 				continue;
 		}
-		/* require full match on deletions */
-		if (req == SIOCDELRT && !equal(&rt->rt_gateway, gate))
-			continue;
-		/* don't keep multiple identical entries */
-		if (req == SIOCADDRT && equal(&rt->rt_gateway, gate)) {
-			error = EEXIST;
-			goto bad;
-		}
-		break;
-	}
-	if (m == 0 && doinghost) {
-		hash = h.afh_nethash;
-		oldmprev = mprev;
-		mprev = &rtnet[hash % RTHASHSIZ];
-		match = afswitch[af].af_netmatch;
-		doinghost = 0;
-		goto again;
-	}
-
-	if (m == 0 && req != SIOCADDRT) {
-		error = ESRCH;
-		goto bad;
+		if (equal(&rt->rt_gateway, &entry->rt_gateway))
+			break;
 	}
-found:
 	switch (req) {
 
 	case SIOCDELRT:
-		rt->rt_flags &= ~RTF_UP;
-		if (rt->rt_refcnt > 0)	/* should we notify protocols? */
-			error = EBUSY;
-		else
-			*mprev = m_free(m);
-		break;
-
-	case SIOCCHGRT:
-		rt->rt_flags = new->rt_flags;
-		if (rt->rt_refcnt > 0)
-			error = EBUSY;
-		else if (!equal(&rt->rt_gateway, gate))
-			goto newneighbor;
+		if (m == 0) {
+			error = ESRCH;
+			goto bad;
+		}
+		*mprev = m->m_next;
+		if (rt->rt_refcnt > 0) {
+			rt->rt_flags &= ~RTF_UP;
+			rttrash++;
+			m->m_next = 0;
+		} else
+			(void) m_free(m);
 		break;
 
 	case SIOCADDRT:
-		m = m_get(M_DONTWAIT);
+		if (m) {
+			error = EEXIST;
+			goto bad;
+		}
+		ifp = if_ifwithaddr(&entry->rt_gateway);
+		if (ifp == 0) {
+			ifp = if_ifwithnet(&entry->rt_gateway);
+			if (ifp == 0) {
+				error = ENETUNREACH;
+				goto bad;
+			}
+		}
+		m = m_get(M_DONTWAIT, MT_RTABLE);
 		if (m == 0) {
 			error = ENOBUFS;
-			break;
+			goto bad;
 		}
+		*mprev = m;
 		m->m_off = MMINOFF;
 		m->m_len = sizeof (struct rtentry);
 		rt = mtod(m, struct rtentry *);
-		*rt = *new;
-		if (new->rt_flags & RTF_HOST) {
-			rt->rt_hash = h.afh_hosthash;
-			*oldmprev = m;
-		} else {
-			rt->rt_hash = h.afh_nethash;
-			*mprev = m;
-		}
-		rt->rt_use = 0;
+		rt->rt_hash = hash;
+		rt->rt_dst = entry->rt_dst;
+		rt->rt_gateway = entry->rt_gateway;
+		rt->rt_flags =
+		    RTF_UP | (entry->rt_flags & (RTF_HOST|RTF_GATEWAY));
 		rt->rt_refcnt = 0;
-newneighbor:
-		rt->rt_ifp = if_ifwithnet(gate);
-		if (rt->rt_ifp == 0)
-			rt->rt_flags &= ~RTF_UP;
+		rt->rt_use = 0;
+		rt->rt_ifp = ifp;
 		break;
 	}
 bad:
@@ -191,14 +282,17 @@ rtinit(dst, gateway, flags)
 	int flags;
 {
 	struct rtentry route;
-	struct route ro;
+	int cmd;
 
+	if (flags == -1) {
+		cmd = (int)SIOCDELRT;
+		flags = 0;
+	} else {
+		cmd = (int)SIOCADDRT;
+	}
+	bzero((caddr_t)&route, sizeof (route));
 	route.rt_dst = *dst;
 	route.rt_gateway = *gateway;
 	route.rt_flags = flags;
-	route.rt_use = 0;
-	(void) rtrequest(SIOCADDRT, &route);
-	ro.ro_rt = 0;
-	ro.ro_dst = *dst;
-	rtalloc(&ro);
+	(void) rtrequest(cmd, &route);
 }