ipfilter: Move userland bits to sbin

Through fixes and improvements our ipfilter sources have diverged
enough to warrant move from contrib into sbin/ipf. Now that I'm
planning on implementing MSS clamping as in iptables it makes more
sense to move ipfilter to sbin.

This is the second of three commits of the ipfilter move.

Suggested by glebius on two occaions.

Suggested by and discussed with:	glebius
Reviewed by:				glebius, kp (for #network)
Differential Revision:		https://reviews.freebsd.org/D33510

(cherry picked from commit 41edb30)

sbin/ipf/Makefile

@@ -3,7 +3,7 @@
 SUBDIR=		libipf .WAIT
 SUBDIR+=	ipf ipfs ipfstat ipmon ipnat ippool
 # XXX Temporarily disconnected.
-# SUBDIR+=	ipftest ipresend
+# SUBDIR+=	ipftest ipresend ipsend
 SUBDIR_PARALLEL=
 
 .include <bsd.subdir.mk>

sbin/ipf/Makefile.inc

@@ -6,10 +6,9 @@ WARNS?=		2
 NO_WFORMAT=
 NO_WARRAY_BOUNDS=
 
-CFLAGS+=	-I${SRCTOP}/contrib/ipfilter
-CFLAGS+=	-I${SRCTOP}/contrib/ipfilter/tools
 CFLAGS+=	-I${SRCTOP}/sys
 CFLAGS+=	-I${SRCTOP}/sys/netpfil/ipfilter
+CFLAGS+=	-I${SRCTOP}/sbin/ipf/common
 CFLAGS+=	-DSTATETOP -D__UIO_EXPOSE
 
 .if ${MK_INET6_SUPPORT} != "no"
@@ -24,9 +23,7 @@ LIBADD+=	ipf
 
 CLEANFILES+=	y.tab.c y.tab.h
 
-.PATH:	${SRCTOP}/contrib/ipfilter		\
-	${SRCTOP}/contrib/ipfilter/lib		\
-	${SRCTOP}/contrib/ipfilter/tools	\
-	${SRCTOP}/contrib/ipfilter/man
+.PATH:	${SRCTOP}/sbin/ipf/libipf		\
+	${SRCTOP}/sbin/ipf/common
 
 .include "../Makefile.inc"

sbin/ipf/ippool/Makefile

@@ -2,7 +2,7 @@
 
 PACKAGE=	ipf
 PROG=		ippool
-SRCS=		${GENHDRS} ippool_y.c ippool_l.c kmem.c ippool.c
+SRCS=		${GENHDRS} ippool_y.c ippool_l.c ippool.c
 MAN=		ippool.5 ippool.8
 CFLAGS+=	-I.
 

sbin/ipf/ipresend/Makefile

@@ -5,6 +5,6 @@ PROG=		ipresend
 SRCS=		ipresend.c ip.c resend.c sbpf.c sock.c 44arp.c
 MAN=		ipresend.1
 
-.PATH:		${SRCTOP}/contrib/ipfilter/ipsend
+.PATH:		${.CURDIR:H}/ipsend
 
 .include <bsd.prog.mk>

sbin/ipf/ipscan/Makefile

@@ -0,0 +1,18 @@
+#	$FreeBSD$
+
+PACKAGE=	ipf
+PROG=		ipscan
+SRCS=		${GENHDRS} ipscan_y.c
+MAN=		ipscan.5 ipscan.8
+MLINKS=		ipscan.5 ipscan.conf.5
+
+GENHDRS+=	ipscan_y.h
+CLEANFILES+=	${GENHDRS} ipscan_y.c
+
+ipscan_y.c: ipscan_y.y
+	${YACC} -d ${.ALLSRC}
+
+ipscan_y.h: ipscan_y.c
+
+
+.include <bsd.prog.mk>

share/examples/ipfilter/Makefile

@@ -4,9 +4,7 @@ PACKAGE=ipf
 FILES=	README
 
 # dist sample files
-.PATH: ${SRCTOP}/contrib/ipfilter/rules \
-       ${SRCTOP}/contrib/ipfilter \
-       ${SRCTOP}/contrib/ipfilter/man
+.PATH: ${.CURDIR}/rules
 FILES+=	BASIC.NAT BASIC_1.FW BASIC_2.FW \
 	example.1 example.2 example.3 example.4 example.5 \
 	example.6 example.7 example.8 example.9 example.10 \