Centroid.EU Blog

(this blog is mostly encrypted - adults only)

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FreeBSD Donation

September 30th, 2016

I have donated $5 to FreeBSD Foundation. This wraps up FreeBSD donations for this year, there is an OpenBSD donation coming in 2 months or so.


Victim of spoofed Mail

September 30th, 2016

I've become victim of spoofed mail. Someone is sending mail with one of my domains to other people, getting them mad, and I receive the bounces. I do have SPF protection records but if the remote SMTP gateways don't enforce SPF records, then it's not helping. Here is the IP's that a "valid" mail from my domains would come from:
This is listed in SPF DNS records for my domains as well. I knew there was a-holes on the Internet, and they finally got to me. Unfortunately there is nothing I can do about this. If there is let me know what. I'm looking for a technical solution.


My IPv6 setup at M-net (german provider)

September 27th, 2016

I recently added IPv6 functionality to my network and had some obstacles to overcome, such as:

  1. How to route deep into my network and assign each host an IP6 that is 2 hops deep.
  2. What to do about rfc1918 IP's, since I want a NAT64/DNS64 setup
  3. How to do NAT66 in order to use deep routes

Well to give you a better idea I'm going to show you my network plan:

Network map:

[gaia]--                    [raspberry pi]
          \                      |              [mercury]
[phone1] - \                     |                  |
            --- [uranus] === [Access Point] --- [gamma] ---- to pppoe cloud
[phone2] - /                    ||
          /                     ||
[beta]--                        ||
                                |   \
                                |    +--[fritzbox LTE]------- to LTE network

Legend:                         Hosts:

--- CAT5 cabling                gaia + spica: apple computers running vmware
=== wifi 5 Ghz                  uranus: OpenBSD i386 on Lanner hw
||  wifi 5 Ghz                  venus: OpenBSD amd64 on Soekris hw
                                gamma: OpenBSD amd64 on PC Engines APU
                                fritzbox: AVM fritzbox router

Here is my dhcp6c.conf file:

keyinfo mnet {
        realm "v6.mnet-online.de";
        keyid 1 ;
        secret "***notshown***";

interface pppoe0 {
        send ia-pd 0 ;
        script "/etc/nat66-up.sh";

id-assoc pd {
        prefix-interface vether0 {
                     sla-id 1 ;
                        sla-len 0 ;
and with that the /etc/nat66-up.sh script:

ADDRESS=`/sbin/ifconfig vether0 | grep inet6 | tail -1 | awk '{print $2}'`
NETWORK=`echo $ADDRESS | awk -F: '{printf("%s:%s:%s:%s:%s:%s::/64\n", $1, \
	$2, $3, $4, $5, $6); }'`

/sbin/pfctl -t nat66 -T flush
/sbin/pfctl -t nat66 -T add $NETWORK

exit 0

I use a vether0 dummy ethernet interface to take on the IPv6 address from my provider (mnet) so that I can give all other interfaces a 2001:db8::/56 address. This address gets translated later in my pf rules and the relevant lines to the pf look like this:

table  persist
table  const { 2001:db8::/56 }
match out on $ext_if inet from  to any nat-to ($ext_if)
match out on $ext_if inet6 from  to any nat-to  round-robin \
pass in on re2 inet6 from any to 64:ff9b::/96 af-to inet from ($ext_if)
pass in on re1 inet6 from any to 64:ff9b::/96 af-to inet from ($ext_if)
I would have liked putting (vether0:network) in place of the but found that it translated to the fe80:: address and not the assigned address from m-net. So I have to do it this way, it's no headache. Also the round-robin was unfortuantely the only mode I got working, I would have liked to use random to get a random IP6 on the outgoing /64.

So let's see what we got, we have native IPv4 NAT44'ed, we have dual-stack IPv6 NAT66'ed and we have NAT64/DNS64 on top of that. It's really cool, to show you how the DNS64 works I'm gonna do a host lookup on censored.net which isn't mine so please look at it just as an example:

beta$ host censored.net
censored.net has address
censored.net has IPv6 address 64:ff9b::4834:45b
censored.net mail is handled by 0 localhost.
Then when I route into 64:ff9b::/96 it gets af-to'ed in the pf rules to an IPv4 address. It's really cool.

What else is missing? I want to show you the DNS setup with BIND from the OpenBSD 6.0 ports, it worked out of the box. Here is what I had to add into the options:

        dns64 64:ff9b::/96 {
                clients { 2001:db8::/56; 192.168/16; };
                mapped { !10/8; !192.168/16; !172.16/12; any; };
                exclude { 64:ff9b::/96; };
                recursive-only yes;

That's really all there is to it, I had a lot of fun doing this and can't wait until some services of mine use IPv6 so that I can drop the native IPv4 completely.


Ordered a book from Amazon

September 20th, 2016

This time I want to learn more about USB. So I got:

  • USB Complete: The Developer's Guide (Complete Guides) - Jan Axelson
Hopefully it was worth it.


Equinox in two days

September 20th, 2016

Equinox is upon us again in two days. last year's equinox was on the 23rd of september and it was chilly in the morning at 10 Celsius. Right now as I write this it's 16 Celsius and I'm hoping I can keep the heat off another week. We'll see.


Stand up for Snowden

September 14th, 2016

There is a website called "pardon Snowden". It asks you to sign a petition to US President Barack Obama to pardon Edward Snowden before he leaves office. At the time of this writing Obama still has 128 days in office. Think about what Snowdens chances are after Obama? Would Trump pardon him? Would Hillary Clinton? Would anyone else? Edward Snowdens whistleblowing which caused him to flee the USA and take up asylum in Russia, caused US citizen no harm and did them a favour in showing how out of hand the surveillance programme in the USA has become. Stand up for your rights by signing the petition! I tried but realised it has to be a US citizen. What sort of a world are we living in anyhow?


TLS for centroid.eu blog, when?

September 14th, 2016

I'm going to restructure the website and the blog probably after the OpenBSD 6.1 release. Apparently there is a program in that release that manages certificates from "let's encrypt". Since I'd want my whole website encrypted I'd have to use let's encrypt several times to fully encrypt my website which contains the domains virgostar.net, solarscale.de and centroid.eu. So if you think the obfuscation is good enough, don't let it fool you, it was made for a defense against bots (that don't know javascript) not to thwart spying eyes. I'd run the same blog software only inside TLS with let's encrypt. Props have to be given to Edward Snowden for his whistleblowing which caused organizations like "let's encrypt" to form in the first place. Encryption should be free!


One more panic chronicle entry

September 9th, 2016

I woke up today to a panic'ed router/gateway. What a way to start the day. backtrace here. Why am I not sending these to OpenBSD anymore? dunno. I remembered there was a reason once.


I had photographed Vega and Constellation Hercules

August 30th, 2016

This picture is from June 27th, 2010 so a little over 6 years ago. My dad and I were on the Peterstirn which is outside of Schweinfurt (the city that I live in). This article is in relevance to the last article and I wanted to show it again. I have made a cut-off from the original RAW Photo and I want to show you this. Feel free to open the photo in another tab to make it it's original size.

As you can see this area of the sky (at least in june) is visible. You just gotta know what to look for. If you can find Vega you can find constellation Lyra and from there the area that's circled which is part of Hercules. Inside the circle somewhere lies the star system that emanates an 11 GHz signal.

Update. I have added the label to a star I think is called Ras Alhague in the constellation Ophiuchus. Constellation Hercules goes further up from here but I don't have that in my photo.


The whereabouts of HD164595 in Hercules

August 30th, 2016

Slashdot made me aware of this story of a SETI signal that was observed, last year by a russian SETI installation.

I have plotted the rough area of HD164595 it's somewhere in the circle but what's important is the relative near-ness to the star Vega. It's in the constellation Hercules, and should be visible this summer with Telescopes. As far as aliens reacting to broadcasts from Earth they have just now recieved signals from 1920's because they are 95 light years away. However they might have been reacting to carbon in our atmosphere due to the start of the industrial revolution in the 1800's. Meaning the aliens have telescopes. It is hypothesized that they are a Kardashev scale I civilization if they are directing this towards only us, so they are more advanced than us.

May they keep the signal going with the strength of Hercules :-).


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