Ticket History #6870: Don't reject AP-REQs based on PACs

pull up r24640 from trunk

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r24640 | ghudson | 2011-02-16 18:34:37 -0500 (Wed, 16 Feb 2011) | 14 lines

ticket: 6870
subject: Don't reject AP-REQs based on PACs
target_version: 1.9.1
tags: pullup

Experience has shown that it was a mistake to fail AP-REQ verification
based on failure to verify the signature of PAC authdata contained in
the ticket. We've had two rounds of interoperability issues with the
hmac-md5 checksum code, an interoperability issue OSX generating
unsigned PACs, and another problem where PACs are copied by older KDCs
from a cross-realm TGT into the service ticket. If a PAC signature
cannot be verified, just don't mark it as verified and continue on
with the AP exchange.

https://github.com/krb5/krb5/commit/028125b8c2ba963cb28710de68706b2bb14c6c3b
Commit By: tlyu
Revision: 24647
Changed Files:
U branches/krb5-1-9/src/include/k5-trace.h
U branches/krb5-1-9/src/lib/krb5/krb/pac.c