Make kprop/kpropd work with RC4 session key

In krb5_auth_con_initivector and mk_priv/rd_priv, stop assuming that
the enctype's block size is the size of the cipher state.  Instead,
make and discard a cipher state to get the size.

(cherry picked from commit 8d01455ec9ed88bd3ccae939961a6e123bb3d45f)

ticket: 7575 (new)
version_fixed: 1.10.4
status: resolved
Convert success in krb5_chpw_result_code_string

Result code 0 used to be converted properly by krb5_set_password,
though not krb5_change_password; this changed in 1.10 when
krb5int_setpw_result_code_string was folded into
krb5_chpw_result_code_string.  Restore the old behavior, and make it
apply to krb5_change_password as well, by making
krb5_chpw_result_code_string convert result code 0.

[ghudson@mit.edu: commit message]

(cherry picked from commit 316bf74b4696058e2b60c95c9d0fc90d6c2c2ffe)

ticket: 7576 (new)
version_fixed: 1.10.4
status: resolved
PKINIT null pointer deref [CVE-2013-1415]

Don't dereference a null pointer when cleaning up.

The KDC plugin for PKINIT can dereference a null pointer when a
malformed packet causes processing to terminate early, leading to
a crash of the KDC process.  An attacker would need to have a valid
PKINIT certificate or have observed a successful PKINIT authentication,
or an unauthenticated attacker could execute the attack if anonymous
PKINIT is enabled.

CVSSv2 vector: AV:N/AC:M/Au:N/C:N/I:N/A:C/E:P/RL:O/RC:C

This is a minimal commit for pullup; style fixes in a followup.
[kaduk@mit.edu: reformat and edit commit message]

(cherry picked from commit c773d3c775e9b2d88bcdff5f8a8ba88d7ec4e8ed)

ticket: 7577 (new)
version_fixed: 1.10.4
status: resolved