Hello,

Superb!

> On 3 Sep 2025, at 18:49, Adolf Belka <[email protected]> wrote:
> 
> Hi Michael,
> 
> On 02/09/2025 16:07, Michael Tremer wrote:
>> Hello Adolf,
>>> On 2 Sep 2025, at 11:34, Adolf Belka <[email protected]> wrote:
>>> 
>>> Hi Michael,
>>> 
>>> On 28/08/2025 10:46, Michael Tremer wrote:
>>>> Hello Adolf,
>>>> This is great.
>>>> I would suggest to create a Git branch somewhere and push those changes 
>>>> right now. That way, we will only have to merge them later and not even 
>>>> think about what changes we need and why.
>>> 
>>> Will do so.
> 
> The changes are located at
> https://git.ipfire.org/?p=people/bonnietwin/ipfire-2.x.git;a=shortlog;h=refs/heads/openvpn-2.7_alpha3
> 
> This includes the sorting out of the status extraction information and the 
> removal of the deprecated persist-key option.
> 
> Removing this worked fine for the server and rw clients. The server.conf and 
> the rw client .ovpn files all no longer have the persist-key option. as they 
> are all created anew when a backup is restored or an update carried out.
> 
> However for the n2n connections, these are stored as already created .conf 
> files and therefore keep the persist-key entry and therefore get the warning 
> about the deprecated option.
> 
> When we do the update of openvpn-2.7 we will need to add in a patch to remove 
> the persist-key from existing n2n connections.
> The same for the backup. I will create an update top the backup.pl file to do 
> this and add it to the above openvpn-2.7 branch.
> 
>>> 
>>> I found in the deprecated options section of OpenVPN a comment that says
>>> 
>>> WARNING: This migration approach will not work after the release of OpenVPN 
>>> v2.7. As of that release, BF-CBC, CAST or RC2 ciphers will not be accepted 
>>> any more.
>>> 
>>> This is in the section on migrating away from deprecated ciphers.
>>> 
>>> However there is also the statement in removal of insecure ciphers
>>> 
>>> For now we will not officially remove them and focus on educating users. 
>>> Maybe at some point the SSL libraries will start dropping them.
>>> 
>>> I tested out running openvpn with BF-CBC in the ciphers-data-fallback and 
>>> got the following message in the openvpn-2.7 logs
>>> 
>>> WARNING: INSECURE cipher (BF-CBC) with block size less than 128 bit (64 
>>> bit).  This allows attacks like SWEET32.  Mitigate by using a --cipher with 
>>> a larger block size (e.g. AES-256-CBC). Support for these insecure ciphers 
>>> will be removed in OpenVPN 2.7.
>>> 
>>> I also then manually changed the server.conf file to have data-ciphers also 
>>> set to BF-CBC and then restarted openvpn-rw and the same above message is 
>>> shown but openvpn-rw is running.
>>> 
>>> So the insecure ciphers will still be accepted but there will be a warning 
>>> in the logs.
>> This should not *really* bother us because we should soon have all servers 
>> supporting NCP. That way, all clients which also support NCP will 
>> automatically migrate away from the statically configured ciphers (no matter 
>> what it is). If people are using clients that are still not supporting NCP 
>> (pre 2.4), those will break when they are removing support for these ciphers 
>> on the server side. However, even 2.5 is already EOL, so nobody should be on 
>> OpenVPN <= 2.3.
>>> On the compression front, I found the following statement in the 
>>> openvpn-2.7 changes
>>> 
>>> --------------
>>> Remove support for compression on send
>>> 
>>> We can't disable compression support on receive because
>>> that would break too many configurations out there. But
>>> we can remove the support for compressing outgoing traffic,
>>> it was disabled by default anyway.
>>> 
>>> Makes "--allow-compression yes" an alias for
>>> "--allow-compression asym" and removes all resulting dead code.
>>> --------------
>>> 
>>> So the compress outgoing was disabled by default anyway but in 2.7 the code 
>>> will no longer exist in openvpn
>>> 
>>> I don't believe this changes how we are using the compress migrate option 
>>> but I thought I would flag it up for you to see.
>>> 
>>> Interesting that they are saying now that they can't as standard disable 
>>> compression support on receive due to so many user configs using it.
>> The configuration might still include “compress”, but actually, OpenVPN 
>> won’t really compress any data any more. The “compress migrate” option might 
>> sometimes add a special header which was formerly required when compression 
>> was enabled, but it won’t compress the payload any more. Currently, our 
>> server is configured to accept compressed packets (if the client really 
>> insists), but it will never send a compressed packed as that would make the 
>> stream vulnerable to the voracle attack.
>> So this should not really affect us. In fact it is a good thing because we 
>> can rely on clients >= 2.7 never to send any compressed data either which 
>> would be a security benefit.
>> So, all green lights from me on the 2.7 front for now!
> 
> I think so also. 2.7 will be much easier than the move from 2.5 to 2.6

I suppose we had a large backlog and are now shipping all sorts of changes in 
one go…

-Michael

> I will also do a test and update of the openvpn-2.7 branch when the beta and 
> rc versions are released.
> 
> Regards,
> 
> Adolf.
> 
>> -Michael
>>> 
>>> Regards,
>>> 
>>> Adolf.
>>> 
>>> 
>>>> Best,
>>>> -Michael
>>>>> On 27 Aug 2025, at 17:58, Adolf Belka <[email protected]> wrote:
>>>>> 
>>>>> Hi Michael,
>>>>> 
>>>>> On 27/08/2025 15:24, Adolf Belka wrote:
>>>>>> Hi Michael,
>>>>>> On 18/08/2025 13:47, Michael Tremer wrote:
>>>>>>> Hello Adolf,
>>>>>>> 
>>>>>>> This is really valuable work because we might have to start 
>>>>>>> transitioning OpenVPN changes a lot sooner than the final release is 
>>>>>>> coming out because of all this bad, static configuration stuff on both 
>>>>>>> sides of the connection.
>>>>>>> 
>>>>>>> But this actually proves the opposite. The —-persist-key option can be 
>>>>>>> easily dropped then. We use it everywhere and it will then become the 
>>>>>>> default. Very good.
>>>>>>> 
>>>>>>> Regarding the status, there have been many changes over the years and 
>>>>>>> it usually should be easy to fix it. Normally more information is being 
>>>>>>> added and we just need to account for it. Hopefully that is a 5 minute 
>>>>>>> job.
>>>>>> Based on your input I had a look at the differences in the status log 
>>>>>> from 2.6 and 2.7
>>>>>> With 2.6 the Real Address is IP:PORT
>>>>>> With 2.7 it is UDP4:IP:PORT
>>>>>> So that definitely looks like it should be easy to fix.
>>>>> 
>>>>> I have tested out some changes and have been able to get the OpenVPN 
>>>>> Connection statistics and the Status display for each of the connection 
>>>>> lines to work again.
>>>>> 
>>>>> So when we come to upgrade to OpenVPN-2.7.x then I know what changes will 
>>>>> be needed.
>>>>> 
>>>>> Regards,
>>>>> 
>>>>> Adolf.
>>>>> 
>>>>> 
>>>>>>> 
>>>>>>> So with this information, I am very relaxed and hopeful that the new 
>>>>>>> 2.7 release will be an easy update for us and everyone using OpenVPN.
>>>>>> It does look like it should not be so stressful an update as we have had 
>>>>>> from 2.5 to 2.6
>>>>>> Regards,
>>>>>> Adolf.
>>>>>>> 
>>>>>>> Best,
>>>>>>> -Michael
>>>>>>> 
>>>>>>>> On 17 Aug 2025, at 14:43, Adolf Belka <[email protected]> wrote:
>>>>>>>> 
>>>>>>>> Hi All,
>>>>>>>> 
>>>>>>>> I have built and done initial testing of CU198 with 
>>>>>>>> OpenVPN-2.7_alpha3. Here is my initial feedback.
>>>>>>>> 
>>>>>>>> My N2N connection connected and I could ping between both ends. The 
>>>>>>>> status on the OpenVPN WUI page showed as Connected.
>>>>>>>> 
>>>>>>>> Only item was that when rebooting the following message shows up in 
>>>>>>>> the boot log when the N2N connection is started
>>>>>>>> 
>>>>>>>> DEPRECATED: --persist-key option ignored. Keys are now always 
>>>>>>>> persisted across restarts.
>>>>>>>> 
>>>>>>>> 
>>>>>>>> I the tested out the old existing Android and Linux Laptop client 
>>>>>>>> connections.
>>>>>>>> 
>>>>>>>> In both cases at the client ends they said they were connected.
>>>>>>>> 
>>>>>>>> On the Linux Laptop I could ping to a PC on the green network. For 
>>>>>>>> both the Linux Laptop and Android phone I could access the WUI page of 
>>>>>>>> the IPFire system. The logs showed that the clients were connected.
>>>>>>>> 
>>>>>>>> However in both cases the OpenVPN WUI page stayed showing the RW 
>>>>>>>> connections as disconnected. Accessing the OpenVPN Connection 
>>>>>>>> Statistics never showed any connection existing.
>>>>>>>> 
>>>>>>>> So the status methodology for the RW's does not seem to be working 
>>>>>>>> with OpenVPN-2.7, even though the connections were successfully 
>>>>>>>> connected and the standard openvpn logs show the rw clients as 
>>>>>>>> connected.
>>>>>>>> 
>>>>>>>> I will have another go with new client connections and see if that 
>>>>>>>> shows anything different with regard to the status.
>>>>>>>> 
>>>>>>>> Also need to remember this is the alpha3 release so there might be 
>>>>>>>> bugs still and maybe that is what I am experiencing.
>>>>>>>> 
>>>>>>>> So RW connections get made but stay showing as disconnected when they 
>>>>>>>> are actually connected.
>>>>>>>> N2N connections show as connected and are connected.
>>>>>>>> 
>>>>>>>> Regards
>>>>>>>> 
>>>>>>>> Adolf



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