Date: Mon, 28 Aug 2006 12:39:31 +0530 From: "Rajkumar S" <rajkumars@gmail.com> To: freebsd-net@freebsd.org Subject: Re: Netgraph plumbing question Message-ID: <64de5c8b0608280009r52aabb4cl11103635419b845d@mail.gmail.com> In-Reply-To: <20060826144424.GC30165@rambler-co.ru> References: <64de5c8b0608250849p2912457cs84c227cc914d1f10@mail.gmail.com> <20060826144424.GC30165@rambler-co.ru>
next in thread | previous in thread | raw e-mail | index | archive | help
On 8/26/06, Ruslan Ermilov <ru@freebsd.org> wrote:
> No, but it's trivial to set up ng_bpf(4) to do it. Since the
> default BPF program will be non-matching, "ifNotMatch" action
> should be used.
Cool!!
While testing this I ran into some difficulty.
> # ngctl
> [...]
> + mkpeer bpf mixed mixed
> + name mixed bpf
> + conn bpf: in1 in1
> + conn bpf: in2 in2
> + conn bpf: out out
So far it's okay.
> + msg bpf: setprogram { thisHook="in1" ifNotMatch="mixed" }
This is not working, and I get an error:
ngctl: send msg: Invalid argument
2 days back, I was playing with bpf for testing packet filtering. I
was using c program for creating bpf nodes and connecting. So today I
wrote a test program to create the steps you have given using ngctl.
In that program also I am getting upto the "conn" commands. But the
msg commands fails. I have put my test program at
http://pastebin.ca/151630
The msg part is:
struct ng_bpf_hookprog bpf_hookprog;
bzero (&bpf_hookprog, sizeof(bpf_hookprog));
strlcpy (bpf_hookprog.thisHook, "in1", sizeof (bpf_hookprog.thisHook));
strlcpy (bpf_hookprog.ifNotMatch, "mixed", sizeof
(bpf_hookprog.ifNotMatch));
if (NgSendMsg(cfd, "bpf:", NGM_GENERIC_COOKIE,
NGM_BPF_SET_PROGRAM, &bpf_hookprog,
sizeof(bpf_hookprog)) < 0) {
perror ("Setup Hooks");
return (-1);
}
If I comment out this part then I get in ngctl list
Name: bpf Type: bpf ID: 0000001c Num hooks: 4
Name: test_socket Type: socket ID: 0000001b Num hooks: 4
Name: ngctl775 Type: socket ID: 00000011 Num hooks: 0
Name: vr0 Type: ether ID: 00000002 Num hooks: 0
Name: rl0 Type: ether ID: 00000001 Num hooks: 0
but if this code fragment is present then:
Name: test_socket Type: socket ID: 0000001d Num hooks: 0
Name: ngctl775 Type: socket ID: 00000011 Num hooks: 0
Name: vr0 Type: ether ID: 00000002 Num hooks: 0
Name: rl0 Type: ether ID: 00000001 Num hooks: 0
the bpf node is absent. I had tested creating a bpf filter also, but
running that also gives the same result. So this is the smallest code
fragment simulating the problem.
Thanks again to you and Julian for all the help.
raj
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?64de5c8b0608280009r52aabb4cl11103635419b845d>