#16 SMTP with Kerberos authentication - MS Exchange 2010 server

[Jaroslaw (Jarek) Polok]

Since the Exchange 2010 SMTP server sends a non-empty initial GSSAPI challenge , alpine is not able to use GSSAPI/Kerberos authentication against it due to the auth_gss.c code rejecting non-empty initial challenges. Attached patch simply disables this check making alpine useable with MS Exchange 2010 Kerberized SMTP.

Looking at RFC4954 (www.ietf.org/rfc/rfc4954.txt) it sems to me that this non-empty initial challenge is legit and it may be used by the server , but alpine code assumes that it must not be used ....

It seems to me that changing the auth_gss.c code to omit the 'initial challenge non-empty check' should not cause any problems

[Jaroslaw (Jarek) Polok]

workaround for MS Exchange 2010 Kerberized SMTP

[Andraž Levstik]

Could this affect anything else? If not I'll commit it ASAP.

[Jaroslaw (Jarek) Polok]

I do not believe so. We use this patch since a year. (~ 800 alpine clients connecting to Exchange servers)

Jarek

BTW: ASAP was year ago ;-)