Re: Issue with iwd + Linux 5.8.3 + WPA Enterprise

[Ard Biesheuvel]

On Wed, 26 Aug 2020 at 08:18, Paul Menzel <pmenzel@xxxxxxxxxxxxx> wrote:
>
>
> Dear Caleb,
>
>
> Thank you for the report. Linux has a no regression policy, so the
> correct forum to report this to is the Linux kernel folks. I am adding
> the crypto and stable folks to the receiver list.
>
> Am 26.08.20 um 07:51 schrieb caljorden@xxxxxxxxxxx:
>
> > I wanted to note an issue that I have hit with iwd when I upgraded to
> > the Linux 5.8.3 stable kernel.  My office network uses WPA Enterprise
> > with EAP-PEAPv0 + MSCHAPv2.  When using this office network,
> > upgrading to Linux 5.8.3 caused my system to refuse to associate
> > successfully to the network.  I get the following in my dmesg logs:
> >
> > [   40.846535] wlan0: authenticate with <redacted>:60
> > [   40.850570] wlan0: send auth to <redacted>:60 (try 1/3)
> > [   40.854627] wlan0: authenticated
> > [   40.855992] wlan0: associate with <redacted>:60 (try 1/3)
> > [   40.860450] wlan0: RX AssocResp from <redacted>:60 (capab=0x411 status=0 aid=11)
> > [   40.861620] wlan0: associated
> > [   41.886503] wlan0: deauthenticating from <redacted>:60 by local choice (Reason: 23=IEEE8021X_FAILED)
> > [   42.360127] wlan0: authenticate with <redacted>:22
> > [   42.364584] wlan0: send auth to <redacted>:22 (try 1/3)
> > [   42.370821] wlan0: authenticated
> > [   42.372658] wlan0: associate with <redacted>:22 (try 1/3)
> > [   42.377426] wlan0: RX AssocResp from <redacted>:22 (capab=0x411 status=0 aid=15)
> > [   42.378607] wlan0: associated
> > [   43.402009] wlan0: deauthenticating from <redacted>:22 by local choice (Reason: 23=IEEE8021X_FAILED)
> > [   43.875921] wlan0: authenticate with <redacted>:60
> > [   43.879988] wlan0: send auth to <redacted>:60 (try 1/3)
> > [   43.886244] wlan0: authenticated
> > [   43.889273] wlan0: associate with <redacted>:60 (try 1/3)
> > [   43.894586] wlan0: RX AssocResp from <redacted>:60 (capab=0x411 status=0 aid=11)
> > [   43.896077] wlan0: associated
> > [   44.918504] wlan0: deauthenticating from <redacted>:60 by local choice (Reason: 23=IEEE8021X_FAILED)
> >
> > This continues as long as I let iwd run.
> >
> > I downgraded back to Linux 5.8.2, and verified that everything works
> > as expected.  I also tried using Linux 5.8.3 on a different system at
> > my home, which uses WPA2-PSK.  It worked fine (though it uses an
> > Atheros wireless card instead of an Intel card - but I assume that is
> > irrelevant).
> >
> > I decided to try to figure out what caused the issue in the changes
> > for Linux 5.8.3.  I assumed that it was something that changed in the
> > crypto interface, which limited my bisection to a very few commits.
> > Sure enough, I found that if I revert commit
> > e91d82703ad0bc68942a7d91c1c3d993e3ad87f0 (crypto: algif_aead - Only
> > wake up when ctx->more is zero), the problem goes away and I am able
> > to associate to my WPA Enterprise network successfully, and use it.
> > I found that in order to revert this commit, I also first had to
> > revert 465c03e999102bddac9b1e132266c232c5456440 (crypto: af_alg - Fix
> > regression on empty requests), because the two commits have coupled
> > changes.
> >
> > I normally would have assumed that this should be sent to the kernel
> > list, but I thought I would first mention it here because of what I
> > found in some email threads on the Linux-Crypto list about the crypto
> > interfaces to the kernel being sub-optimal and needing to be fixed.
> > The changes in these commits look like they are just trying to fix
> > what could be broken interfaces, so I thought that it would make
> > sense to see what the iwd team thinks about the situation first.
> >
> > The wireless card I was using during this testing is an Intel
> > Wireless 3165 (rev 81).  If there is any additional information I
> > could help provide, please let me know.
>
> It’d be great, if you verified, if the problem occurs with Linus’ master
> branch too.
>

It would be helpful if someone could explain for the non-mac80211
enlightened readers how iwd's EAP-PEAPv0 + MSCHAPv2 support relies on
the algif_aead socket interface, and which AEAD algorithms it uses. I
assume this is part of libell?