From: Alexander Bluhm <alexander.bluhm@gmx.net>
Subject: split in_pcbrtentry() and in6_pcbnotify()
To: tech@openbsd.org
Date: Tue, 30 Jan 2024 18:29:27 +0100

Hi,

Can we split in_pcbrtentry() and in6_pcbnotify() with the usual
INP_IPV6 check?

This means less #ifdef INET6 in the function.

Also struct route_in6 *ro is of the correct type and we don't rely
on the fact that inp_route and inp_route6 are pointers to the same
union.

ok?

bluhm

Index: netinet/in_pcb.c
===================================================================
RCS file: /cvs/src/sys/netinet/in_pcb.c,v
diff -u -p -r1.287 in_pcb.c
--- netinet/in_pcb.c	28 Jan 2024 20:34:25 -0000	1.287
+++ netinet/in_pcb.c	30 Jan 2024 17:21:45 -0000
@@ -909,6 +909,11 @@ in_pcbrtentry(struct inpcb *inp)
 {
 	struct route *ro;
 
+#ifdef INET6
+	if (ISSET(inp->inp_flags, INP_IPV6))
+		in6_pcbrtentry(inp);
+#endif
+
 	ro = &inp->inp_route;
 
 	/* check if route is still valid */
@@ -921,34 +926,16 @@ in_pcbrtentry(struct inpcb *inp)
 	 * No route yet, so try to acquire one.
 	 */
 	if (ro->ro_rt == NULL) {
-#ifdef INET6
-		memset(ro, 0, sizeof(struct route_in6));
-#else
 		memset(ro, 0, sizeof(struct route));
-#endif
 
-#ifdef INET6
-		if (ISSET(inp->inp_flags, INP_IPV6)) {
-			if (IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6))
-				return (NULL);
-			ro->ro_dst.sa_family = AF_INET6;
-			ro->ro_dst.sa_len = sizeof(struct sockaddr_in6);
-			satosin6(&ro->ro_dst)->sin6_addr = inp->inp_faddr6;
-			ro->ro_tableid = inp->inp_rtableid;
-			ro->ro_rt = rtalloc_mpath(&ro->ro_dst,
-			    &inp->inp_laddr6.s6_addr32[0], ro->ro_tableid);
-		} else
-#endif /* INET6 */
-		{
-			if (inp->inp_faddr.s_addr == INADDR_ANY)
-				return (NULL);
-			ro->ro_dst.sa_family = AF_INET;
-			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
-			satosin(&ro->ro_dst)->sin_addr = inp->inp_faddr;
-			ro->ro_tableid = inp->inp_rtableid;
-			ro->ro_rt = rtalloc_mpath(&ro->ro_dst,
-			    &inp->inp_laddr.s_addr, ro->ro_tableid);
-		}
+		if (inp->inp_faddr.s_addr == INADDR_ANY)
+			return (NULL);
+		ro->ro_dst.sa_family = AF_INET;
+		ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
+		satosin(&ro->ro_dst)->sin_addr = inp->inp_faddr;
+		ro->ro_tableid = inp->inp_rtableid;
+		ro->ro_rt = rtalloc_mpath(&ro->ro_dst,
+		    &inp->inp_laddr.s_addr, ro->ro_tableid);
 	}
 	return (ro->ro_rt);
 }
Index: netinet/in_pcb.h
===================================================================
RCS file: /cvs/src/sys/netinet/in_pcb.h,v
diff -u -p -r1.149 in_pcb.h
--- netinet/in_pcb.h	28 Jan 2024 20:34:25 -0000	1.149
+++ netinet/in_pcb.h	30 Jan 2024 17:21:45 -0000
@@ -367,6 +367,8 @@ struct rtentry *
 	in_pcbrtentry(struct inpcb *);
 
 /* INET6 stuff */
+struct rtentry *
+	in6_pcbrtentry(struct inpcb *);
 void	in6_pcbnotify(struct inpcbtable *, const struct sockaddr_in6 *,
 	u_int, const struct sockaddr_in6 *, u_int, u_int, int, void *,
 	void (*)(struct inpcb *, int));
Index: netinet6/in6_pcb.c
===================================================================
RCS file: /cvs/src/sys/netinet6/in6_pcb.c,v
diff -u -p -r1.133 in6_pcb.c
--- netinet6/in6_pcb.c	28 Jan 2024 20:34:25 -0000	1.133
+++ netinet6/in6_pcb.c	30 Jan 2024 17:21:46 -0000
@@ -561,6 +561,35 @@ in6_pcbnotify(struct inpcbtable *table, 
 	rw_exit_write(&table->inpt_notify);
 }
 
+struct rtentry *
+in6_pcbrtentry(struct inpcb *inp)
+{
+	struct route_in6 *ro = &inp->inp_route6;
+
+	/* check if route is still valid */
+	if (!rtisvalid(ro->ro_rt)) {
+		rtfree(ro->ro_rt);
+		ro->ro_rt = NULL;
+	}
+
+	/*
+	 * No route yet, so try to acquire one.
+	 */
+	if (ro->ro_rt == NULL) {
+		memset(ro, 0, sizeof(struct route_in6));
+
+		if (IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6))
+			return (NULL);
+		ro->ro_dst.sin6_family = AF_INET6;
+		ro->ro_dst.sin6_len = sizeof(struct sockaddr_in6);
+		ro->ro_dst.sin6_addr = inp->inp_faddr6;
+		ro->ro_tableid = inp->inp_rtableid;
+		ro->ro_rt = rtalloc_mpath(sin6tosa(&ro->ro_dst),
+		    &inp->inp_laddr6.s6_addr32[0], ro->ro_tableid);
+	}
+	return (ro->ro_rt);
+}
+
 struct inpcb *
 in6_pcbhash_lookup(struct inpcbtable *table, uint64_t hash, u_int rdomain,
     const struct in6_addr *faddr, u_short fport,
Index: netinet6/ip6_output.c
===================================================================
RCS file: /cvs/src/sys/netinet6/ip6_output.c,v
diff -u -p -r1.283 ip6_output.c
--- netinet6/ip6_output.c	18 Jan 2024 11:03:16 -0000	1.283
+++ netinet6/ip6_output.c	30 Jan 2024 17:21:47 -0000
@@ -1486,7 +1486,7 @@ do { \
 			if (!(so->so_state & SS_ISCONNECTED))
 				return (ENOTCONN);
 
-			rt = in_pcbrtentry(inp);
+			rt = in6_pcbrtentry(inp);
 			if (!rtisvalid(rt))
 				return (EHOSTUNREACH);