ports VS openssh-portable

I think OpenBSD comes the closest to what you want with its two easy to use syscalls that provide syscall filtering and restricting access to paths:

https://man.openbsd.org/pledge.2

https://man.openbsd.org/unveil.2

A few random examples:

https://github.com/tmux/tmux/blob/c8494dff7b6b9a996866edaf8c...

https://github.com/openbsd/ports/blob/master/www/mozilla-fir...

https://github.com/openbsd/ports/blob/master/www/mozilla-fir...

To get the best isolation you need to patch the source — the application needs to go through initial setup and then drop privileges to the absolute possible minimum. But it's easy to make custom wrappers for third-party applications — the above profiles taken from the OpenBSD ports tree are the proof.

Have you checked the no-ip port: https://github.com/openbsd/ports/blob/master/net/no-ip/pkg/noip2.rc

> https://github.com/openbsd/ports/commit/bf33ea5f3ff390d8cde3...

Now, this is surprising. I randomly clicked on that link and I immediately see that the code and the patch has a bug. It only checks the first 8 characters:

    -      if (gr != NULL && strncmp(gr->gr_name, "operator", 8) == 0)

Some people are working around this by using obsdfreqd, some by patching sys/kern/sched_bsd.c (change if (hw_power) to if (0 && hw_power)), some by simply setting to a lower speed (sysctl hw.perfpolicy=manual and hw.setperf=99 might be enough as this disables turbo mode found on some CPUs).

You could also look into a port that has a hard dependency on openssl like: https://github.com/openbsd/ports/tree/master/security/sslscan

For me it's the ease of management and good documentation.

For example, during 6.8 to 6.9 upgrade, there was a major postgresql upgrade.

It is mentioned in the doc https://www.openbsd.org/faq/upgrade69.html (see Special packages at the bottom).

You're redirected to the package README with special instructions on how to setup and upgrade: https://github.com/openbsd/ports/blob/master/databases/postg...

Et voilà, everything is explained.

On debian, if I am not careful, I'll do an upgrade and risk breaking something during a db migration (I'm looking at you MySQL upgrades...).

Godot engine gamecontroller support. This is limited and incomplete, but it's a start. A huge number of indie games made with Godot are released every week; most of which work at least partially with an XBox {360,One} controller. You can follow This Week in Godot if you're interested.

> OpenBSD has handled this case for some years. I do not know if there was any breakage or fallout from this.

The other thing about OpenBSD is that when they make a change to their OS, they also go through to make sure all the (third-party) ports/packages:

* https://cvsweb.openbsd.org/ports/

* https://github.com/openbsd/ports

do not break. So they're create patches for the software and and submit them upstream.

Default for the last 24 years according to https://github.com/openssh/openssh-portable/blame/385ecb31e1...

They didn't need to use the library to make use of the systemd notify mechanism, which is simple to interface and quite a nice feature in the first place.

The free-standing implementation: https://github.com/openssh/openssh-portable/commit/08f579231...

Unless I'm misunderstanding what this is about RFC5647 merely points out that the sequence number is included as AAD due to RFC4253 requirements. The [email protected] specification is not exactly the most rigorous thing I've ever seen (https://github.com/openssh/openssh-portable/blob/master/PROT...) but reading it, the sequence number is only included in the IV, and not as AAD, which directly runs afoul of the RFC4253 section 6.4 requirement for it to be included in the MAC.

The key layout is described in https://github.com/openssh/openssh-portable/blob/master/PROT... and you can view it pretty easily via

cat private_key_here | head -n -1 | tail -n +2 | base64 -d | xxd

One I created in 2016 is using aes256-cbc with bcrypt for the kdf, which isn't awful at all.

Interestingly, it looks like ssh-agent disables core dumps[1], but I don't see similar usage for sshd

1: https://github.com/openssh/openssh-portable/blob/694150ad927...

There's a current pull request for adding AF_UNIX support, which should make all kinds of exciting forwarding possible, since it will make it easy to proxy ssh connections through an arbitrary local process which can do anything to forward the data to the remote end.

https://github.com/openssh/openssh-portable/pull/431

OpenSSH server (allows connecting to containers)

It doesn't, at least not for generic/unmodified cryptographic applications.

WebAuthN signatures are of a very specific challenge/response format that applications need to explicitly support. For example, SSH had to add new key and signature formats [1] to support it.

Theoretically, a blockchain/cryptocurrency application could adopt the WebAuthN signature format as its canonical or an alternative signature format, but I'm not aware of any popular one having done so.

[1] https://github.com/openssh/openssh-portable/blob/master/PROT...

I just tested it and looked at the code briefly; the client fortunately does seem to remove all keys not provided by the server: https://github.com/openssh/openssh-portable/blob/36c6c3eff5e...

It seems like at least a `known_hosts` compromise would be "self-healing" after connecting to the legitimate github.com server once.