Hi Alan, Thank you very much for addressing this. To give a bit more context on why I went down this rabbit hole: I was researching options for handling "partial failures", specifically the "chicken and egg" scenario where a user certificate is missing on a freshly provisioned device. That led me to a "Wires and Wi-Fi" blog post describing how TEAP is based on EAP-FASTv2 and how EAP chaining allows the server to make decisions based on combined states, including "User Failed and Machine Succeeded" (https://www.wiresandwi.fi/blog/windows-network-authentication-sequence). According to that explanation, Windows can perform machine-only authentication during startup, even when the user certificate does not exist yet, and the RADIUS server can return an Access-Accept with a restricted authorization profile. This gives the device enough limited network access to reach the PKI and enroll the missing user certificate. I also found a Cisco ISE guide showing this workflow in practice, with explicit rules for "Machine authenticated, User not" that grant reduced access, distinct from the full "User and Machine" success state. (https://www.ise-support.com/2020/05/29/using-teap-for-eap-chaining/). Based on these examples, it appears that several commercial platforms intentionally treat the session as successful overall (sending Access-Accept), even when one inner method fails, and rely on the authorization layer to map that combined state to the appropriate access level. This also implies that the Windows TEAP supplicant is willing to accept a TEAP Success result even when an inner EAP conversation completed with a failure.
You will have to update the "eap_teap.c" code to allow TEAP to continue when one of the inner methods fails. Right now, an inner reject results in the entire TEAP session failing. You can't edit the configuration to allow this. When the TEAP code was written, I was assuming that failure means failure. If the Windows TEAP implementation is OK with the above work flow, then that's a surprising bit of information.
Given that this "partial success with restricted access" behavior seems to have become a de facto standard method for handling similar scenarios, I wanted to ask whether FreeRADIUS would consider supporting this mode?. Or is the project's stance that FreeRADIUS should follow the RFC strictly until the specification explicitly allows this behavior? Best regards, Jan K. On Tue, Dec 9, 2025 at 5:14 PM Alan DeKok via Freeradius-Users <freeradius-users@lists.freeradius.org> wrote:
On Dec 9, 2025, at 11:06 AM, Jan Kříž <jan.kriz1867@gmail.com> wrote:
I'm following up on a thread from with the subject of "EAP-TEAP not doing 2nd inner Method" from December 2024 (https://lists.freeradius.org/pipermail/freeradius-users/2024-December/105155...) about TEAP and setting network policies based on partial success (e.g., Machine cert succeeds, but User cert fails).
I really don't see how that is supported by anything. I've spent about 3 years going over the TEAP specifications, and the TEAP implementations. I don't see anything in them which allows that work flow.
The inner authentications are bound to the outer TLS session via various crypto magic. The result is that the outer authentication succeeds only when the inner authentication succeeds.
So I don't see any way in the specification which could allow machine EAP-TLS to succeed, fail at user EAP-TLS, but still allow the user online.
I could very well be missing something. But if I am, then this behavior is not explicitly allowed by the specification. So it's an accidental outcome. The specification needs to be updated to mention this, and then either explicitly allow it, or forbid it.
I agree that the client side is a huge hurdle here, but I’m confused because some commercial platforms like Cisco ISE and Aruba ClearPass explicitly advertise and allow admins to configure different VLANs/ACLs precisely for that partial success scenario.
Since the commercial vendors seem to have found a way to achieve this, are they relying on some vendor-specific extensions or a different, non-TEAP chaining method entirely? Is it possible to configure this in FreeRADIUS at all?
You'll have to try it and see. I don't have time right now to test it, unfortunately.
Any insight into how FreeRADIUS could be configured to accurately process the final result and differentiate between Machine-only, User-only success and Full success would be hugely helpful.
You will have to update the "eap_teap.c" code to allow TEAP to continue when one of the inner methods fails. Right now, an inner reject results in the entire TEAP session failing.
You can't edit the configuration to allow this. When the TEAP code was written, I was assuming that failure means failure. If the Windows TEAP implementation is OK with the above work flow, then that's a surprising bit of information.
Alan DeKok.
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