Recycle IFF_NOTRAILERS into IFF_STATICARP and document ownerhsip

of IFF* flags.

inputs from jmc@, ok bluhm@, visa@

sbin/ifconfig/brconfig.h

@@ -1,4 +1,4 @@
-/*	$OpenBSD: brconfig.h,v 1.11 2016/09/02 10:01:36 goda Exp $	*/
+/*	$OpenBSD: brconfig.h,v 1.12 2018/01/16 10:33:55 mpi Exp $	*/
 
 /*
  * Copyright (c) 2009 Claudio Jeker <claudio@openbsd.org>
@@ -70,7 +70,7 @@ void switch_datapathid(const char *, int);
 void switch_portno(const char *, const char *);
 
 #define	IFFBITS								\
-	"\024\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5POINTOPOINT\6NOTRAILERS" \
+	"\024\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5POINTOPOINT\6STATICARP" \
 	"\7RUNNING\10NOARP\11PROMISC\12ALLMULTI\13OACTIVE\14SIMPLEX"	\
 	"\15LINK0\16LINK1\17LINK2\20MULTICAST"	\
 	"\23INET6_NOPRIVACY\24MPLS\25WOL\26AUTOCONF6"

sbin/ifconfig/ifconfig.8

@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ifconfig.8,v 1.291 2017/11/30 07:41:01 jmc Exp $
+.\"	$OpenBSD: ifconfig.8,v 1.292 2018/01/16 10:33:55 mpi Exp $
 .\"	$NetBSD: ifconfig.8,v 1.11 1996/01/04 21:27:29 pk Exp $
 .\"     $FreeBSD: ifconfig.8,v 1.16 1998/02/01 07:03:29 steve Exp $
 .\"
@@ -31,7 +31,7 @@
 .\"
 .\"     @(#)ifconfig.8	8.4 (Berkeley) 6/1/94
 .\"
-.Dd $Mdocdate: November 30 2017 $
+.Dd $Mdocdate: January 16 2018 $
 .Dt IFCONFIG 8
 .Os
 .Sh NAME
@@ -147,8 +147,6 @@ Use of this option is discouraged in favour of
 Enable the use of the Address Resolution Protocol (ARP)
 in mapping
 between network level addresses and link level addresses (default).
-This is currently implemented for mapping between
-DARPA Internet addresses and Ethernet addresses.
 .It Cm -arp
 Disable the use of ARP.
 .It Cm broadcast Ar addr
@@ -454,6 +452,12 @@ and
 .Xr pf.conf 5 .
 .It Cm -rtlabel
 Clear the route label.
+.It Cm staticarp
+If ARP is enabled, the host will only reply to requests for its addresses,
+and will never send any requests.
+.It Cm -staticarp
+If ARP is enabled, the host will perform normally,
+sending out requests and listening for replies.
 .It Cm up
 Mark an interface
 .Dq up .

sbin/ifconfig/ifconfig.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: ifconfig.c,v 1.352 2018/01/09 10:02:02 mpi Exp $	*/
+/*	$OpenBSD: ifconfig.c,v 1.353 2018/01/16 10:33:55 mpi Exp $	*/
 /*	$NetBSD: ifconfig.c,v 1.40 1997/10/01 02:19:43 enami Exp $	*/
 
 /*
@@ -397,6 +397,8 @@ const struct	cmd {
 	{ "rtlabel",	NEXTARG,	0,		setifrtlabel },
 	{ "-rtlabel",	-1,		0,		setifrtlabel },
 	{ "rdomain",	NEXTARG,	0,		setrdomain },
+	{ "staticarp",	IFF_STATICARP,	0,		setifflags },
+	{ "-staticarp",	-IFF_STATICARP,	0,		setifflags },
 	{ "mpls",	IFXF_MPLS,	0,		setifxflags },
 	{ "-mpls",	-IFXF_MPLS,	0,		setifxflags },
 	{ "mplslabel",	NEXTARG,	0,		setmpelabel },

sbin/route/route.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: route.c,v 1.206 2017/10/18 07:31:31 mpi Exp $	*/
+/*	$OpenBSD: route.c,v 1.207 2018/01/16 10:33:55 mpi Exp $	*/
 /*	$NetBSD: route.c,v 1.16 1996/04/15 18:27:05 cgd Exp $	*/
 
 /*
@@ -1268,7 +1268,7 @@ char routeflags[] =
 "\020PROTO1\021CLONED\022CACHED\023MPATH\025MPLS\026LOCAL\027BROADCAST"
 "\030CONNECTED\031BFD";
 char ifnetflags[] =
-"\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5PTP\6NOTRAILERS\7RUNNING\010NOARP\011PPROMISC"
+"\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5PTP\6STATICARP\7RUNNING\010NOARP\011PPROMISC"
 "\012ALLMULTI\013OACTIVE\014SIMPLEX\015LINK0\016LINK1\017LINK2\020MULTICAST";
 char addrnames[] =
 "\1DST\2GATEWAY\3NETMASK\4GENMASK\5IFP\6IFA\7AUTHOR\010BRD\011SRC\012SRCMASK\013LABEL\014BFD\015DNS\016STATIC\017SEARCH";

sys/net/if.h

@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.h,v 1.189 2017/12/21 01:11:47 dlg Exp $	*/
+/*	$OpenBSD: if.h,v 1.190 2018/01/16 10:33:55 mpi Exp $	*/
 /*	$NetBSD: if.h,v 1.23 1996/05/07 02:40:27 thorpej Exp $	*/
 
 /*
@@ -184,34 +184,43 @@ struct if_status_description {
  */
 #define	IFDESCRSIZE	64
 
-#define	IFF_UP		0x1		/* interface is up */
-#define	IFF_BROADCAST	0x2		/* broadcast address valid */
-#define	IFF_DEBUG	0x4		/* turn on debugging */
-#define	IFF_LOOPBACK	0x8		/* is a loopback net */
-#define	IFF_POINTOPOINT	0x10		/* interface is point-to-point link */
-#define	IFF_NOTRAILERS	0x20		/* avoid use of trailers */
-#define	IFF_RUNNING	0x40		/* resources allocated */
-#define	IFF_NOARP	0x80		/* no address resolution protocol */
-#define	IFF_PROMISC	0x100		/* receive all packets */
-#define	IFF_ALLMULTI	0x200		/* receive all multicast packets */
-#define	IFF_OACTIVE	0x400		/* transmission in progress */
-#define	IFF_SIMPLEX	0x800		/* can't hear own transmissions */
-#define	IFF_LINK0	0x1000		/* per link layer defined bit */
-#define	IFF_LINK1	0x2000		/* per link layer defined bit */
-#define	IFF_LINK2	0x4000		/* per link layer defined bit */
-#define	IFF_MULTICAST	0x8000		/* supports multicast */
+/*
+ * Interface flags can be either owned by the stack or the driver.  The
+ * symbols below document who is toggling which flag.
+ *
+ *	I	immutable after creation
+ *	N	written by the stack (upon user request)
+ *	d	written by the driver
+ *	c	for userland compatibility only
+ */
+#define	IFF_UP		0x1		/* [N] interface is up */
+#define	IFF_BROADCAST	0x2		/* [I] broadcast address valid */
+#define	IFF_DEBUG	0x4		/* [N] turn on debugging */
+#define	IFF_LOOPBACK	0x8		/* [I] is a loopback net */
+#define	IFF_POINTOPOINT	0x10		/* [I] is point-to-point link */
+#define	IFF_STATICARP	0x20		/* [N] only static ARP */
+#define	IFF_RUNNING	0x40		/* [d] resources allocated */
+#define	IFF_NOARP	0x80		/* [N] no address resolution protocol */
+#define	IFF_PROMISC	0x100		/* [N] receive all packets */
+#define	IFF_ALLMULTI	0x200		/* [d] receive all multicast packets */
+#define	IFF_OACTIVE	0x400		/* [c] transmission in progress */
+#define	IFF_SIMPLEX	0x800		/* [I] can't hear own transmissions */
+#define	IFF_LINK0	0x1000		/* [N] per link layer defined bit */
+#define	IFF_LINK1	0x2000		/* [N] per link layer defined bit */
+#define	IFF_LINK2	0x4000		/* [N] per link layer defined bit */
+#define	IFF_MULTICAST	0x8000		/* [I] supports multicast */
 
 /* flags set internally only: */
 #define	IFF_CANTCHANGE \
 	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|\
 	    IFF_SIMPLEX|IFF_MULTICAST|IFF_ALLMULTI)
 
-#define	IFXF_MPSAFE		0x1		/* if_start is mpsafe */
-#define	IFXF_CLONED		0x2		/* pseudo interface */
-#define	IFXF_INET6_NOPRIVACY	0x4		/* don't autoconf privacy */
-#define	IFXF_MPLS		0x8		/* supports MPLS */
-#define	IFXF_WOL		0x10		/* wake on lan enabled */
-#define	IFXF_AUTOCONF6		0x20		/* v6 autoconf enabled */
+#define	IFXF_MPSAFE		0x1	/* [I] if_start is mpsafe */
+#define	IFXF_CLONED		0x2	/* [I] pseudo interface */
+#define	IFXF_INET6_NOPRIVACY	0x4	/* [N] don't autoconf privacy */
+#define	IFXF_MPLS		0x8	/* [N] supports MPLS */
+#define	IFXF_WOL		0x10	/* [N] wake on lan enabled */
+#define	IFXF_AUTOCONF6		0x20	/* [N] v6 autoconf enabled */
 
 #define	IFXF_CANTCHANGE \
 	(IFXF_MPSAFE|IFXF_CLONED)

sys/netinet/if_ether.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ether.c,v 1.232 2018/01/15 13:48:31 bluhm Exp $	*/
+/*	$OpenBSD: if_ether.c,v 1.233 2018/01/16 10:33:55 mpi Exp $	*/
 /*	$NetBSD: if_ether.c,v 1.31 1996/05/11 12:59:58 mycroft Exp $	*/
 
 /*
@@ -356,7 +356,7 @@ arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
 		return (0);
 	}
 
-	if (ifp->if_flags & IFF_NOARP)
+	if (ifp->if_flags & (IFF_NOARP|IFF_STATICARP))
 		goto bad;
 
 	/*

usr.sbin/route6d/route6d.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: route6d.c,v 1.92 2017/08/23 11:25:07 jca Exp $	*/
+/*	$OpenBSD: route6d.c,v 1.93 2018/01/16 10:33:55 mpi Exp $	*/
 /*	$KAME: route6d.c,v 1.111 2006/10/25 06:38:13 jinmei Exp $	*/
 
 /*
@@ -2334,12 +2334,7 @@ do { \
 	IFFLAG("DEBUG", IFF_DEBUG);
 	IFFLAG("LOOPBACK", IFF_LOOPBACK);
 	IFFLAG("POINTOPOINT", IFF_POINTOPOINT);
-#ifdef IFF_NOTRAILERS
-	IFFLAG("NOTRAILERS", IFF_NOTRAILERS);
-#endif
-#ifdef IFF_SMART
-	IFFLAG("SMART", IFF_SMART);
-#endif
+	IFFLAG("STATICARP", IFF_STATICARP);
 	IFFLAG("RUNNING", IFF_RUNNING);
 	IFFLAG("NOARP", IFF_NOARP);
 	IFFLAG("PROMISC", IFF_PROMISC);