IPDIVERT is a module now and tell the other parts of the kernel about it.

IPDIVERT depends on IPFIREWALL being loaded or compiled into the kernel.

sys/conf/NOTES

@@ -622,7 +622,8 @@ device		stf			#6to4 IPv6 over IPv4 encapsulation
 # means that you won't get stuck if the kernel and /sbin/ipfw binary get
 # out of sync.
 #
-# IPDIVERT enables the divert IP sockets, used by ``ipfw divert''
+# IPDIVERT enables the divert IP sockets, used by ``ipfw divert''.  It
+# depends on IPFIREWALL if compiled into the kernel.
 #
 # IPFIREWALL_FORWARD enables changing of the packet destination either
 # to do some sort of policy routing or transparent proxying.  Used by

sys/modules/Makefile

@@ -106,6 +106,7 @@ SUBDIR=	${_3dfx} \
 	${_iir} \
 	${_io} \
 	ip6fw \
+	ipdivert \
 	${_ipfilter} \
 	ipfw \
 	ip_mroute_mod \

sys/modules/ipfw/Makefile

@@ -14,9 +14,5 @@ CFLAGS+= -DIPFIREWALL
 #If you want it to pass all packets by default
 #CFLAGS+= -DIPFIREWALL_DEFAULT_TO_ACCEPT
 #
-#If you want it with divert(4) support (kernel must be compiled
-#with "options IPDIVERT" for this to work)
-#CFLAGS+= -DIPDIVERT
-#
 
 .include <bsd.kmod.mk>

sys/netinet/ip_divert.c

@@ -31,10 +31,14 @@
 
 #if !defined(KLD_MODULE)
 #include "opt_inet.h"
+#include "opt_ipfw.h"
 #include "opt_mac.h"
 #ifndef INET
 #error "IPDIVERT requires INET."
 #endif
+#ifndef IPFIREWALL
+#error "IPDIVERT requires IPFIREWALL"
+#endif
 #endif
 
 #include <sys/param.h>