wpa_supplicant: TNCC support reentrant ?

Jouni Malinen j
Mon Apr 13 02:17:16 PDT 2009

On Mon, Apr 13, 2009 at 10:04:56AM +0900, r.ooba at ictec.co.jp wrote:

> - Is TNCC support the multi interface ?
>   (Wireless LAN and Wired LAN etc, for instance.)

Do you mean concurrent negotiations for multiple network interfaces? I
don't think there is any explicit support for this and in practice, this
may show up as multiple TNCC instances trying to use the IMC at the same

> - Is TNCC support reentrant ? 
>   (Please, refer to the TNC_IFIMC_v1_2_r8.pdf, p.17,
>   3.3 Threading and Reentrancy.)
> - Is TNCC support thread-safe ? 
>   (Please, refer to the TNC_IFIMC_v1_2_r8.pdf, p.40,
>   4.2.4 Threading.)

I don't think the current version would handle multiple IMC threads
nicely, i.e., there is currently no synchronization or protection on
data since the code in wpa_supplicant assumes everything to live in a
single thread. Eventually, the TNCC code would need to handle this in a
way that isolates the possibility of calls from other threads from
confusing the core wpa_supplicant code.

Jouni Malinen                                            PGP id EFC895FA

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