Set ipv6 default route

I have a box that sends out radvd announcements on a lan, but something on the lan makes the other machines forget the advertisement about the default gateway after a while. They remember their ipv6 address, but cannot connect outside the lan anymore.

Before I used to log in to the machine with radvd and restart it so that it sends out fresh advertisements, but I'm now trying to explicitly add the default route with

read -p host: m;
ssh -t ${m:?} sudo ip -6 route add default via fe80::2b0:d0ff:febe:5fd7 dev eth0

Let's see how that goes...

Building bochs

The required libraries must be installed somewhere,
I let MacPorts build and install bochs to get
the libraries installed into /opt/local

Download bochs from svn in SRC, configure and make:

cd $SRC

CFLAGS="-I/opt/local/include -arch i386" \
CXXFLAGS="-L/opt/local/lib -arch i386" \
LDFLAGS="-L/opt/local/lib -arch i386" \
./configure \
--exec-prefix=/opt/local \
--bindir=/opt/local/bin \
--mandir=/opt/local/share/man \
--enable-all-optimizations \
--enable-cdrom \
--with-vbe \
--without-x \
--with-sdl

make -j8

Make a HD image

./bximage -q -hd -mode=sparse -size=1024 $SRC/c.img

./bochs

Configure hard disks, cdrom, bios files and boot order to boot from cdrom.
Use these files

$SRC/c.img
~/Downloads/ubuntu-10.04.2-server-i386.iso

$SRC/bios/BIOS-bochs-latest
$SRC/bios/VGABIOS-lgpl-latest


To make it faster, change the default ips from 50000000 to 4000000
cpu: count=1, ips=4000000, ....

Using a pure python disassembler for x86_64 machine code

Get some machine code, for instance with otool -t /bin/ls | head

$ otool -t /bin/ls | head
/bin/ls:
(__TEXT,__text) section
0000000100001478 6a 00 48 89 e5 48 83 e4 f0 48 8b 7d 08 48 8d 75 
0000000100001488 10 89 fa 83 c2 01 c1 e2 03 48 01 f2 48 89 d1 eb 
0000000100001498 04 48 83 c1 08 48 83 39 00 75 f6 48 83 c1 08 e8 
00000001000014a8 58 0f 00 00 89 c7 e8 1b 39 00 00 f4 55 48 89 e5 
00000001000014b8 48 8d 47 68 48 8d 7e 68 48 89 c6 c9 e9 01 3a 00 
00000001000014c8 00 55 48 89 e5 48 83 c6 68 48 83 c7 68 c9 e9 ef 
00000001000014d8 39 00 00 55 48 89 e5 53 48 89 f1 48 8b 56 60 48 
00000001000014e8 8b 47 60 48 8b 58 30 48 39 5a 30 7f 1d 7c 22 48

Get pymsasid from http://code.google.com/p/pymsasid/

$ wget http://pymsasid.googlecode.com/files/pymsasid-0.31.zip
$ unzip pymsasid-0.31.zip
$ cd pymsasid-0.3

Run it

$ python

import pymsasid
code = "6a 00 48 89 e5 48 83 e4 f0 48 8b 7d 08 48 8d 75 10"
p=pymsasid.Pymsasid(source=code,hook=pymsasid.HexstringHook,vendor=pymsasid.VENDOR_AMD)
p.dis_mode = 64
p.pc = 0x0000000100001478
for i in range(5): print p.decode()

will print

push 0x0 
mov rbp rsp 
and rsp 0xf0 
mov rdi [rbp+0x8] 
lea rsi [rbp+0x10]