Subject: tcpdump and routing header
To: None <>
From: Martti Kuparinen <>
List: current-users
Date: 12/11/2000 16:46:40

I'm implementing Mobile IPv6 on NetBSD 1.5 from scratch as a hobby.
So far I have a fully functional Corresponding Node implementation :-)
My plan is to publish the code when it's little bit more mature so
please don't ask me more about this yet...

I have discovered that tcpdump is showing wrong address when
displaying a Routing Header. Below is an example:

13:29:32.988805 3ffe:xxxx:xxxx:332:200:39ff:fe8e:1420 > 3ffe:xxxx:xxxx:350:210:5aff:fe2d:535f: srcrt (len=2, type=0, segleft=1, [0]3b01:7:b00:1:0:151:0:151)[|DSTOPT]no next header
    6000 0000 0028 2b40 3ffe xxxx xxxx 0332
    0200 39ff fe8e 1420 3ffe xxxx xxxx 0350
    0210 5aff fe2d 535f 3c02 0001 0000 0000
    3ffe xxxx xxxx 0300 0210 5aff fe2d 535f
    3b01 0007 0b00 0001 0000 0151 0000 0151

The Routing Header 0 is here:

                        3c02 0001 0000 0000
    3ffe xxxx xxxx 0300 0210 5aff fe2d 535f     <== address

The remaining 16 bytes are for PAD1 and Binding Acknowledgement.

As you can see address[0] should be 3ffe:xxxx:xxxx:300:0210:5aff:fe2d:535f
and not the content of the Binding Acknowledgement!

Could someone take a look at tcpdump and maybe upgrade it to the latest
version? It works on my old FreeBSD 3.4 + KAME SNAP (2000-0?-??) but
I want to use NetBSD...

PS. Could you send a CC: to me as I'm not on this list!


Martti Kuparinen <>