ng_ksocket as divert socket is broken

[Gleb Smirnoff]

  Andre,

  I've recently noticed a regression between RELENG_5 and CURRENT.
In CURRENT ng_ksocket is unable to work as divert socket. Since
you have touched divert code recently I'm asking you. Today I'm
going to dig deeply there, but probably you can give some ideas
without investigation.

A test for this functionality looks like this:

/usr/sbin/ngctl -f- <<-SEQ
	mkpeer echo dummy dummy
	name .:dummy echo_div
	mkpeer echo_div: ksocket echo inet/raw/divert
	name echo_div:echo div_sock
	rmhook dummy
	msg div_sock: bind inet/0.0.0.0:8888
SEQ

ipfw add 1000 divert 8888 all from any to any via fxp0

And packets should flow thru fxp0 in both directions. Do not
try lo0, there are some problems in there.

You also need this patch (going to commit it soon), if you are
running INVARIANTS:

--- ip_divert.c 25 Oct 2004 20:02:34 -0000      1.106
+++ ip_divert.c 9 Nov 2004 08:27:24 -0000
@@ -277,7 +277,7 @@
        struct divert_tag *dt;
        int error = 0;
 
-       KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
+       m->m_pkthdr.rcvif = NULL;
 
        if (control)
                m_freem(control);               /* XXX */

-- 
Totus tuus, Glebius.
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