sync with OpenBSD -current

sys/net/route.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: route.c,v 1.422 2023/04/28 20:03:14 mvs Exp $	*/
+/*	$OpenBSD: route.c,v 1.426 2023/11/13 17:18:27 bluhm Exp $	*/
 /*	$NetBSD: route.c,v 1.14 1996/02/13 22:00:46 christos Exp $	*/
 
 /*
@@ -158,15 +158,17 @@ int			rttrash;	/* routes not in table but not freed */
 struct pool	rtentry_pool;		/* pool for rtentry structures */
 struct pool	rttimer_pool;		/* pool for rttimer structures */
 
-int	rt_setgwroute(struct rtentry *, u_int);
-void	rt_putgwroute(struct rtentry *);
+int	rt_setgwroute(struct rtentry *, const struct sockaddr *, u_int);
+void	rt_putgwroute(struct rtentry *, struct rtentry *);
 int	rtflushclone1(struct rtentry *, void *, u_int);
 int	rtflushclone(struct rtentry *, unsigned int);
 int	rt_ifa_purge_walker(struct rtentry *, void *, unsigned int);
-struct rtentry *rt_match(struct sockaddr *, uint32_t *, int, unsigned int);
-int	rt_clone(struct rtentry **, struct sockaddr *, unsigned int);
+struct rtentry *rt_match(const struct sockaddr *, uint32_t *, int,
+    unsigned int);
+int	rt_clone(struct rtentry **, const struct sockaddr *, unsigned int);
 struct sockaddr *rt_plentosa(sa_family_t, int, struct sockaddr_in6 *);
-static int rt_copysa(struct sockaddr *, struct sockaddr *, struct sockaddr **);
+static int rt_copysa(const struct sockaddr *, const struct sockaddr *,
+    struct sockaddr **);
 
 #define	LABELID_MAX	50000
 
@@ -229,7 +231,8 @@ rtisvalid(struct rtentry *rt)
  * NDP), if it does not exist.
  */
 struct rtentry *
-rt_match(struct sockaddr *dst, uint32_t *src, int flags, unsigned int tableid)
+rt_match(const struct sockaddr *dst, uint32_t *src, int flags,
+    unsigned int tableid)
 {
 	struct rtentry		*rt = NULL;
 
@@ -247,7 +250,8 @@ rt_match(struct sockaddr *dst, uint32_t *src, int flags, unsigned int tableid)
 }
 
 int
-rt_clone(struct rtentry **rtp, struct sockaddr *dst, unsigned int rtableid)
+rt_clone(struct rtentry **rtp, const struct sockaddr *dst,
+    unsigned int rtableid)
 {
 	struct rt_addrinfo	 info;
 	struct rtentry		*rt = *rtp;
@@ -294,7 +298,7 @@ rt_clone(struct rtentry **rtp, struct sockaddr *dst, unsigned int rtableid)
 } while (0)
 
 int
-rt_hash(struct rtentry *rt, struct sockaddr *dst, uint32_t *src)
+rt_hash(struct rtentry *rt, const struct sockaddr *dst, uint32_t *src)
 {
 	uint32_t a, b, c;
 
@@ -307,12 +311,12 @@ rt_hash(struct rtentry *rt, struct sockaddr *dst, uint32_t *src)
 	switch (dst->sa_family) {
 	case AF_INET:
 	    {
-		struct sockaddr_in *sin;
+		const struct sockaddr_in *sin;
 
 		if (!ipmultipath)
 			return (-1);
 
-		sin = satosin(dst);
+		sin = satosin_const(dst);
 		a += sin->sin_addr.s_addr;
 		b += src[0];
 		mix(a, b, c);
@@ -321,12 +325,12 @@ rt_hash(struct rtentry *rt, struct sockaddr *dst, uint32_t *src)
 #ifdef INET6
 	case AF_INET6:
 	    {
-		struct sockaddr_in6 *sin6;
+		const struct sockaddr_in6 *sin6;
 
 		if (!ip6_multipath)
 			return (-1);
 
-		sin6 = satosin6(dst);
+		sin6 = satosin6_const(dst);
 		a += sin6->sin6_addr.s6_addr32[0];
 		b += sin6->sin6_addr.s6_addr32[2];
 		c += src[0];
@@ -355,7 +359,7 @@ rt_hash(struct rtentry *rt, struct sockaddr *dst, uint32_t *src)
  * Allocate a route, potentially using multipath to select the peer.
  */
 struct rtentry *
-rtalloc_mpath(struct sockaddr *dst, uint32_t *src, unsigned int rtableid)
+rtalloc_mpath(const struct sockaddr *dst, uint32_t *src, unsigned int rtableid)
 {
 	return (rt_match(dst, src, RT_RESOLVE, rtableid));
 }
@@ -368,7 +372,7 @@ rtalloc_mpath(struct sockaddr *dst, uint32_t *src, unsigned int rtableid)
  * longer valid, try to cache it.
  */
 struct rtentry *
-rtalloc(struct sockaddr *dst, int flags, unsigned int rtableid)
+rtalloc(const struct sockaddr *dst, int flags, unsigned int rtableid)
 {
 	return (rt_match(dst, NULL, flags, rtableid));
 }
@@ -378,7 +382,7 @@ rtalloc(struct sockaddr *dst, int flags, unsigned int rtableid)
  * the gateway entry ``rt''.
  */
 int
-rt_setgwroute(struct rtentry *rt, u_int rtableid)
+rt_setgwroute(struct rtentry *rt, const struct sockaddr *gate, u_int rtableid)
 {
 	struct rtentry *prt, *nhrt;
 	unsigned int rdomain = rtable_l2(rtableid);
@@ -386,10 +390,8 @@ rt_setgwroute(struct rtentry *rt, u_int rtableid)
 
 	NET_ASSERT_LOCKED();
 
-	KASSERT(ISSET(rt->rt_flags, RTF_GATEWAY));
-
 	/* If we cannot find a valid next hop bail. */
-	nhrt = rt_match(rt->rt_gateway, NULL, RT_RESOLVE, rdomain);
+	nhrt = rt_match(gate, NULL, RT_RESOLVE, rdomain);
 	if (nhrt == NULL)
 		return (ENOENT);
 
@@ -422,7 +424,7 @@ rt_setgwroute(struct rtentry *rt, u_int rtableid)
 			return (EHOSTUNREACH);
 		}
 
-		error = rt_clone(&prt, rt->rt_gateway, rdomain);
+		error = rt_clone(&prt, gate, rdomain);
 		if (error) {
 			rtfree(prt);
 			return (error);
@@ -439,10 +441,6 @@ rt_setgwroute(struct rtentry *rt, u_int rtableid)
 		return (ENETUNREACH);
 	}
 
-	/* Next hop is valid so remove possible old cache. */
-	rt_putgwroute(rt);
-	KASSERT(rt->rt_gwroute == NULL);
-
 	/*
 	 * If the MTU of next hop is 0, this will reset the MTU of the
 	 * route to run PMTUD again from scratch.
@@ -459,7 +457,8 @@ rt_setgwroute(struct rtentry *rt, u_int rtableid)
 	nhrt->rt_flags |= RTF_CACHED;
 	nhrt->rt_cachecnt++;
 
-	rt->rt_gwroute = nhrt;
+	/* commit */
+	rt_putgwroute(rt, nhrt);
 
 	return (0);
 }
@@ -468,24 +467,29 @@ rt_setgwroute(struct rtentry *rt, u_int rtableid)
  * Invalidate the cached route entry of the gateway entry ``rt''.
  */
 void
-rt_putgwroute(struct rtentry *rt)
+rt_putgwroute(struct rtentry *rt, struct rtentry *nhrt)
 {
-	struct rtentry *nhrt = rt->rt_gwroute;
+	struct rtentry *onhrt;
 
 	NET_ASSERT_LOCKED();
 
-	if (!ISSET(rt->rt_flags, RTF_GATEWAY) || nhrt == NULL)
+	if (!ISSET(rt->rt_flags, RTF_GATEWAY))
 		return;
 
-	KASSERT(ISSET(nhrt->rt_flags, RTF_CACHED));
-	KASSERT(nhrt->rt_cachecnt > 0);
+	/* this is protected as per [X] in route.h */
+	onhrt = rt->rt_gwroute;
+	rt->rt_gwroute = nhrt;
 
-	--nhrt->rt_cachecnt;
-	if (nhrt->rt_cachecnt == 0)
-		nhrt->rt_flags &= ~RTF_CACHED;
+	if (onhrt != NULL) {
+		KASSERT(onhrt->rt_cachecnt > 0);
+		KASSERT(ISSET(onhrt->rt_flags, RTF_CACHED));
 
-	rtfree(rt->rt_gwroute);
-	rt->rt_gwroute = NULL;
+		--onhrt->rt_cachecnt;
+		if (onhrt->rt_cachecnt == 0)
+			CLR(onhrt->rt_flags, RTF_CACHED);
+
+		rtfree(onhrt);
+	}
 }
 
 void
@@ -513,7 +517,10 @@ rtfree(struct rtentry *rt)
 #ifdef MPLS
 	rt_mpls_clear(rt);
 #endif
-	free(rt->rt_gateway, M_RTABLE, ROUNDUP(rt->rt_gateway->sa_len));
+	if (rt->rt_gateway != NULL) {
+		free(rt->rt_gateway, M_RTABLE,
+		    ROUNDUP(rt->rt_gateway->sa_len));
+	}
 	free(rt_key(rt), M_RTABLE, rt_key(rt)->sa_len);
 
 	pool_put(&rtentry_pool, rt);
@@ -796,7 +803,7 @@ rtrequest_delete(struct rt_addrinfo *info, u_int8_t prio, struct ifnet *ifp,
 	}
 
 	/* Release next hop cache before flushing cloned entries. */
-	rt_putgwroute(rt);
+	rt_putgwroute(rt, NULL);
 
 	/* Clean up any cloned children. */
 	if (ISSET(rt->rt_flags, RTF_CLONING))
@@ -932,9 +939,11 @@ rtrequest(int req, struct rt_addrinfo *info, u_int8_t prio,
 		    tableid))) {
 			ifafree(ifa);
 			rtfree(rt->rt_parent);
-			rt_putgwroute(rt);
-			free(rt->rt_gateway, M_RTABLE,
-			    ROUNDUP(rt->rt_gateway->sa_len));
+			rt_putgwroute(rt, NULL);
+			if (rt->rt_gateway != NULL) {
+				free(rt->rt_gateway, M_RTABLE,
+				    ROUNDUP(rt->rt_gateway->sa_len));
+			}
 			free(ndst, M_RTABLE, ndst->sa_len);
 			pool_put(&rtentry_pool, rt);
 			return (error);
@@ -965,9 +974,11 @@ rtrequest(int req, struct rt_addrinfo *info, u_int8_t prio,
 		if (error != 0) {
 			ifafree(ifa);
 			rtfree(rt->rt_parent);
-			rt_putgwroute(rt);
-			free(rt->rt_gateway, M_RTABLE,
-			    ROUNDUP(rt->rt_gateway->sa_len));
+			rt_putgwroute(rt, NULL);
+			if (rt->rt_gateway != NULL) {
+				free(rt->rt_gateway, M_RTABLE,
+				    ROUNDUP(rt->rt_gateway->sa_len));
+			}
 			free(ndst, M_RTABLE, ndst->sa_len);
 			pool_put(&rtentry_pool, rt);
 			return (EEXIST);
@@ -988,27 +999,35 @@ rtrequest(int req, struct rt_addrinfo *info, u_int8_t prio,
 }
 
 int
-rt_setgate(struct rtentry *rt, struct sockaddr *gate, u_int rtableid)
+rt_setgate(struct rtentry *rt, const struct sockaddr *gate, u_int rtableid)
 {
 	int glen = ROUNDUP(gate->sa_len);
-	struct sockaddr *sa;
+	struct sockaddr *sa, *osa;
+	int error = 0;
 
-	if (rt->rt_gateway == NULL || glen != ROUNDUP(rt->rt_gateway->sa_len)) {
-		sa = malloc(glen, M_RTABLE, M_NOWAIT);
-		if (sa == NULL)
-			return (ENOBUFS);
-		if (rt->rt_gateway != NULL) {
-			free(rt->rt_gateway, M_RTABLE,
-			    ROUNDUP(rt->rt_gateway->sa_len));
-		}
-		rt->rt_gateway = sa;
-	}
-	memmove(rt->rt_gateway, gate, glen);
+	KASSERT(gate != NULL);
+	if (rt->rt_gateway == gate) {
+		/* nop */
+		return (0);
+	};
+
+	sa = malloc(glen, M_RTABLE, M_NOWAIT | M_ZERO);
+	if (sa == NULL)
+		return (ENOBUFS);
+	memcpy(sa, gate, gate->sa_len);
+
+	KERNEL_LOCK(); /* see [X] in route.h */
+	osa = rt->rt_gateway;
+	rt->rt_gateway = sa;
 
 	if (ISSET(rt->rt_flags, RTF_GATEWAY))
-		return (rt_setgwroute(rt, rtableid));
+		error = rt_setgwroute(rt, gate, rtableid);
+	KERNEL_UNLOCK();
 
-	return (0);
+	if (osa != NULL)
+		free(osa, M_RTABLE, ROUNDUP(osa->sa_len));
+
+	return (error);
 }
 
 /*
@@ -1051,7 +1070,8 @@ rt_maskedcopy(struct sockaddr *src, struct sockaddr *dst,
  * that is useable for the routing table.
  */
 static int
-rt_copysa(struct sockaddr *src, struct sockaddr *mask, struct sockaddr **dst)
+rt_copysa(const struct sockaddr *src, const struct sockaddr *mask,
+    struct sockaddr **dst)
 {
 	static const u_char maskarray[] = {
 	    0x0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe };
@@ -1563,7 +1583,7 @@ rt_timer_timer(void *arg)
 
 #ifdef MPLS
 int
-rt_mpls_set(struct rtentry *rt, struct sockaddr *src, uint8_t op)
+rt_mpls_set(struct rtentry *rt, const struct sockaddr *src, uint8_t op)
 {
 	struct sockaddr_mpls	*psa_mpls = (struct sockaddr_mpls *)src;
 	struct rt_mpls		*rt_mpls;
@@ -1601,7 +1621,7 @@ rt_mpls_clear(struct rtentry *rt)
 #endif
 
 u_int16_t
-rtlabel_name2id(char *name)
+rtlabel_name2id(const char *name)
 {
 	struct rt_label		*label, *p;
 	u_int16_t		 new_id = 1, id = 0;