Ticket History #6651: Handle migration from pre-1.7 databases with master key kvno != 1 (1.8 pullup)

pull up r23676, r23679 from trunk

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r23679 | ghudson | 2010-01-31 16:04:48 -0500 (Sun, 31 Jan 2010) | 4 lines

ticket: 6650

Fix minor error-handling bug in r23676.

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r23676 | ghudson | 2010-01-28 16:39:31 -0500 (Thu, 28 Jan 2010) | 17 lines

ticket: 6650
subject: Handle migration from pre-1.7 databases with master key kvno != 1
target_version: 1.7.1
tags: pullup

krb5_dbe_lookup_mkvno assumes an mkvno of 1 for entries with no
explicit tl_data. We've seen at least one pre-1.7 KDB with a master
kvno of 0, violating this assumption. Fix this as follows:

* krb5_dbe_lookup_mkvno outputs 0 instead of 1 if no tl_data exists.
* A new function krb5_dbe_get_mkvno translates this 0 value to the
minimum version number in the mkey_list. (krb5_dbe_lookup_mkvno
cannot do this as it doesn't take the mkey_list as a parameter.)
* Call sites to krb5_dbe_lookup_mkvno are converted to
krb5_dbe_get_mkvno, except for an LDAP case where it is acceptable
to store 0 if the mkvno is unknown.

https://github.com/krb5/krb5/commit/3eedece445a3c9abfbcc65493b6d5f4f51699e68
Commit By: tlyu
Revision: 23703
Changed Files:
U branches/krb5-1-8/src/include/kdb.h
U branches/krb5-1-8/src/kadmin/dbutil/kdb5_mkey.c
U branches/krb5-1-8/src/lib/kadm5/srv/svr_principal.c
U branches/krb5-1-8/src/lib/kdb/kdb5.c
U branches/krb5-1-8/src/lib/kdb/libkdb5.exports