Remove sysctl net.inet6.ip6.v6only

This sysctl is a no-op, read-only since it was introduced.  There are no
plans to support IPv4-mapped addresses on OpenBSD, thus this sysctl is
meaningless.

Noticed by djm@, ok claudio@ mpi@ sthen@ henning@

5 files changed, 12 insertions, 17 deletions

diff --git a/sys/netinet6/in6.h b/sys/netinet6/in6.h
index 6e10b7bf9bc..82548d432f9 100644
--- a/sys/netinet6/in6.h
+++ b/sys/netinet6/in6.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in6.h,v 1.87 2015/12/03 10:34:24 tedu Exp $	*/
+/*	$OpenBSD: in6.h,v 1.88 2016/05/19 11:34:39 jca Exp $	*/
 /*	$KAME: in6.h,v 1.83 2001/03/29 02:55:07 jinmei Exp $	*/
 
 /*
@@ -577,8 +577,7 @@ ifatoia6(struct ifaddr *ifa)
 #define IPV6CTL_DEFMCASTHLIM	18
 #define IPV6CTL_USE_DEPRECATED	21	/* use deprecated addr (RFC2462 5.5.4) */
 #define IPV6CTL_RR_PRUNE	22	/* walk timer for router renumbering */
-#define IPV6CTL_V6ONLY		24
-/* 25 to 40: resrved */
+/* 24 to 40: reserved */
 #define IPV6CTL_MAXFRAGS	41	/* max fragments */
 #define IPV6CTL_MFORWARDING	42
 #define IPV6CTL_MULTIPATH	43
@@ -622,7 +621,7 @@ ifatoia6(struct ifaddr *ifa)
 	{ "use_deprecated", CTLTYPE_INT }, \
 	{ "rr_prune", CTLTYPE_INT }, \
 	{ 0, 0 }, \
-	{ "v6only", CTLTYPE_INT }, \
+	{ 0, 0 }, \
 	{ 0, 0 }, \
 	{ 0, 0 }, \
 	{ 0, 0 }, \
diff --git a/sys/netinet6/in6_proto.c b/sys/netinet6/in6_proto.c
index 101e36864eb..38da42d6364 100644
--- a/sys/netinet6/in6_proto.c
+++ b/sys/netinet6/in6_proto.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in6_proto.c,v 1.84 2015/12/03 21:57:59 mpi Exp $	*/
+/*	$OpenBSD: in6_proto.c,v 1.85 2016/05/19 11:34:40 jca Exp $	*/
 /*	$KAME: in6_proto.c,v 1.66 2000/10/10 15:35:47 itojun Exp $	*/
 
 /*
@@ -282,7 +282,6 @@ int	ip6_use_deprecated = 1;	/* allow deprecated addr (RFC2462 5.5.4) */
 int	ip6_rr_prune = 5;	/* router renumbering prefix
 				 * walk list every 5 sec.    */
 int	ip6_mcast_pmtu = 0;	/* enable pMTU discovery for multicast? */
-const int ip6_v6only = 1;
 int	ip6_neighborgcthresh = 2048; /* Threshold # of NDP entries for GC */
 int	ip6_maxifprefixes = 16; /* Max acceptable prefixes via RA per IF */
 int	ip6_maxifdefrouters = 16; /* Max acceptable def routers via RA */
diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index fa856e7ebac..83fd0fc2915 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_input.c,v 1.159 2016/05/07 09:58:06 mpi Exp $	*/
+/*	$OpenBSD: ip6_input.c,v 1.160 2016/05/19 11:34:40 jca Exp $	*/
 /*	$KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 itojun Exp $	*/
 
 /*
@@ -1369,8 +1369,6 @@ ip6_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
 		return (ENOTDIR);
 
 	switch (name[0]) {
-	case IPV6CTL_V6ONLY:
-		return sysctl_rdint(oldp, oldlenp, newp, ip6_v6only);
 	case IPV6CTL_DAD_PENDING:
 		return sysctl_rdint(oldp, oldlenp, newp, ip6_dad_pending);
 	case IPV6CTL_STATS:
diff --git a/sys/netinet6/ip6_output.c b/sys/netinet6/ip6_output.c
index da3e9bcf095..bac8542240a 100644
--- a/sys/netinet6/ip6_output.c
+++ b/sys/netinet6/ip6_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_output.c,v 1.206 2016/04/29 11:40:27 bluhm Exp $	*/
+/*	$OpenBSD: ip6_output.c,v 1.207 2016/05/19 11:34:40 jca Exp $	*/
 /*	$KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $	*/
 
 /*
@@ -1237,11 +1237,11 @@ do { \
 						error = EINVAL;
 						break;
 					}
-					if ((ip6_v6only && optval) ||
-					    (!ip6_v6only && !optval))
-						error = 0;
-					else
+					/* No support for IPv4-mapped addresses. */
+					if (!optval)
 						error = EINVAL;
+					else
+						error = 0;
 					break;
 				case IPV6_RECVTCLASS:
 					OPTSET(IN6P_TCLASS);
@@ -1493,7 +1493,7 @@ do { \
 					break;
 
 				case IPV6_V6ONLY:
-					optval = (ip6_v6only != 0); /* XXX */
+					optval = 1;
 					break;
 
 				case IPV6_PORTRANGE:
diff --git a/sys/netinet6/ip6_var.h b/sys/netinet6/ip6_var.h
index 35f13547600..5f6d961b38a 100644
--- a/sys/netinet6/ip6_var.h
+++ b/sys/netinet6/ip6_var.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_var.h,v 1.58 2016/04/27 21:14:29 markus Exp $	*/
+/*	$OpenBSD: ip6_var.h,v 1.59 2016/05/19 11:34:40 jca Exp $	*/
 /*	$KAME: ip6_var.h,v 1.33 2000/06/11 14:59:20 jinmei Exp $	*/
 
 /*
@@ -222,7 +222,6 @@ extern int	ip6_use_deprecated;	/* allow deprecated addr as source */
 extern int	ip6_rr_prune;		/* router renumbering prefix
 					 * walk list every 5 sec.    */
 extern int	ip6_mcast_pmtu;		/* path MTU discovery for multicast */
-extern const int	ip6_v6only;
 extern int	ip6_neighborgcthresh; /* Threshold # of NDP entries for GC */
 extern int	ip6_maxifprefixes; /* Max acceptable prefixes via RA per IF */
 extern int	ip6_maxifdefrouters; /* Max acceptable def routers via RA */