------ Original Message ------
From "Adolf Belka" <[email protected]>
To "Michael Tremer" <[email protected]>
Cc "IPFire: Development-List" <[email protected]>
Date 12/30/2025 8:05:20 AM
Subject Re: Let's launch our own blocklists...
Hi Michael,
On 29/12/2025 13:05, Michael Tremer wrote:
Hello everyone,
I hope everyone had a great Christmas and a couple of quiet days to relax from
all the stress that was the year 2025.
Still relaxing.
Having a couple of quieter days, I have been working on a new, little
(hopefully) side project that has probably been high up on our radar since the
Shalla list has shut down in 2020, or maybe even earlier. The goal of the
project is to provide good lists with categories of domain names which are
usually used to block access to these domains.
I simply call this IPFire DNSBL which is short for IPFire DNS Blocklists.
How did we get here?
As stated before, the URL filter feature in IPFire has the problem that there
are not many good blocklists available any more. There used to be a couple more
- most famously the Shalla list - but we are now down to a single list from the
University of Toulouse. It is a great list, but it is not always the best fit
for all users.
Then there has been talk about whether we could implement more blocking
features into IPFire that don’t involve the proxy. Most famously blocking over
DNS. The problem here remains a the blocking feature is only as good as the
data that is fed into it. Some people have been putting forward a number of
lists that were suitable for them, but they would not have replaced the
blocking functionality as we know it. Their aim is to provide “one list for
everything” but that is not what people usually want. It is targeted at a
classic home user and the only separation that is being made is any
adult/porn/NSFW content which usually is put into a separate list.
It would have been technically possible to include these lists and let the
users decide, but that is not the aim of IPFire. We want to do the job for the
user so that their job is getting easier. Including obscure lists that don’t
have a clear outline of what they actually want to block (“bad content” is not
a category) and passing the burden of figuring out whether they need the
“Light”, “Normal”, “Pro”, “Pro++”, “Ultimate” or even a “Venti” list with cream
on top is really not going to work. It is all confusing and will lead to a bad
user experience.
An even bigger problem that is however completely impossible to solve is bad
licensing of these lists. A user has asked the publisher of the HaGeZi list
whether they could be included in IPFire and under what terms. The response was
that the list is available under the terms of the GNU General Public License
v3, but that does not seem to be true. The list contains data from various
sources. Many of them are licensed under incompatible licenses (CC BY-SA 4.0,
MPL, Apache2, …) and unless there is a non-public agreement that this data may
be redistributed, there is a huge legal issue here. We would expose our users
to potential copyright infringement which we cannot do under any circumstances.
Furthermore many lists are available under a non-commercial license which
excludes them from being used in any kind of business. Plenty of IPFire systems
are running in businesses, if not even the vast majority.
In short, these lists are completely unusable for us. Apart from HaGeZi, I
consider OISD to have the same problem.
Enough about all the things that are bad. Let’s talk about the new, good things:
Many blacklists on the internet are an amalgamation of other lists. These lists
vary in quality with some of them being not that good and without a clear focus
and others being excellent data. Since we don’t have the man power to start
from scratch, I felt that we can copy the concept that HaGeZi and OISD have
started and simply create a new list that is based on other lists at the
beginning to have a good starting point. That way, we have much better control
over what is going on these lists and we can shape and mould them as we need
them. Most importantly, we don’t create a single lists, but many lists that
have a clear focus and allow users to choose what they want to block and what
not.
So the current experimental stage that I am in has these lists:
* Ads
* Dating
* DoH
* Gambling
* Malware
* Porn
* Social
* Violence
The categories have been determined by what source lists we have available with
good data and are compatible with our chosen license CC BY-SA 4.0. This is the
same license that we are using for the IPFire Location database, too.
The main use-cases for any kind of blocking are to comply with legal
requirements in networks with children (i.e. schools) to remove any kind of
pornographic content, sometimes block social media as well. Gambling and
violence are commonly blocked, too. Even more common would be filtering
advertising and any malicious content.
The latter is especially difficult because so many source lists throw phishing,
spyware, malvertising, tracking and other things into the same bucket. Here
this is currently all in the malware list which has therefore become quite
large. I am not sure whether this will stay like this in the future or if we
will have to make some adjustments, but that is exactly why this is now
entering some larger testing.
What has been built so far? In order to put these lists together properly,
track any data about where it is coming from, I have built a tool in Python
available here:
https://git.ipfire.org/?p=dnsbl.git;a=summary
This tool will automatically update all lists once an hour if there have been
any changes and export them in various formats. The exported lists are
available for download here:
https://dnsbl.ipfire.org/lists/
The download using dnsbl.ipfire.org/lists/squidguard.tar.gz as the custom url
works fine.
However you need to remember not to put the https:// at the front of the url
otherwise the WUI page completes without any error messages but leaves an error
message in the system logs saying
URL filter blacklist - ERROR: Not a valid URL filter blacklist
I found this out the hard way.
The other thing I noticed is that if you already have the Toulouse University
list downloaded and you then change to the ipfire custom url then all the
existing Toulouse blocklists stay in the directory on IPFire and so you end up
with a huge number of category tick boxes, most of which are the old Toulouse
ones, which are still available to select and it is not clear which ones are
from Toulouse and which ones from IPFire.
I think if the blocklist URL source is changed or a custom url is provided the
first step should be to remove the old ones already existing.
That might be a problem because users can also create their own blocklists and
I believe those go into the same directory.
Without clearing out the old blocklists you end up with a huge number of
checkboxes for lists but it is not clear what happens if there is a category
that has the same name for the Toulouse list and the IPFire list such as
gambling. I will have a look at that and see what happens.
Not sure what the best approach to this is.
To find the older files I used this:
find /var/ipfire/urlfilter/blacklists -mtime +365 -type f -ls
To delete the older files and folders I did this:
find /var/ipfire/urlfilter/blacklists -mtime +365 -type f -delete -o
-type d -empty -delete
Manually deleting all contents of the urlfilter/blacklists/ directory and then
selecting the IPFire blocklist url for the custom url I end up with only the 8
categories from the IPFire list.
I have tested some gambling sites from the IPFire list and the block worked on
some. On others the site no longer exists so there is nothing to block or has
been changed to an https site and in that case it went straight through. Also
if I chose the http version of the link, it was automatically changed to https
and went through without being blocked.
If you download and open any of the files, you will see a large header that
includes copyright information and lists all sources that have been used to
create the individual lists. This way we ensure maximum transparency, comply
with the terms of the individual licenses of the source lists and give credit
to the people who help us to put together the most perfect list for our users.
I would like this to become a project that is not only being used in IPFire. We
can and will be compatible with other solutions like AdGuard, PiHole so that
people can use our lists if they would like to even though they are not using
IPFire. Hopefully, these users will also feed back to us so that we can improve
our lists over time and make them one of the best options out there.
All lists are available as a simple text file that lists the domains. Then
there is a hosts file available as well as a DNS zone file and an RPZ file.
Each list is individually available to be used in squidGuard and there is a
larger tarball available with all lists that can be used in IPFire’s URL Filter.
I tested the URL Filter with the change to the autoupdate.urls. For me
it only picked up one URL but I think my Web Proxy is configured wrong.
• Is the non-Transparent needed to utilize the IPFire DNSBL (a.k.a.
IPFire DNS Blocklists)??
• Does Web Proxy Auto-Discovery Protocol (WPAD) need to be setup?
I ask because I disabled the Web Proxy once Shalla Services stopped a
few years ago.
I think the answer is yes to get HTTPS sites recognized.
I am planning to add Suricata/Snort signatures whenever I have time to do so.
Even though it is not a good idea to filter pornographic content this way, I
suppose that catching malware and blocking DoH are good use-cases for an IPS.
Time will tell…
As a start, we will make these lists available in IPFire’s URL Filter and
collect some feedback about how we are doing. Afterwards, we can see where else
we can take this project.
If you want to enable this on your system, simply add the URL to your
autoupdate.urls file like here:
https://git.ipfire.org/?p=people/ms/ipfire-2.x.git;a=commitdiff;h=bf675bb937faa7617474b3cc84435af3b1f7f45f
I also tested out adding the IPFire url to autoupdate.urls and that also worked
fine for me.
Regards,
Adolf.
This email is just a brain dump from me to this list. I would be happy to
answer any questions about implementation details, etc. if people are
interested. Right now, this email is long enough already…
All the best,
-Michael
-- Sent from my laptop
