If the canonicalize flag is set, the MIT KDC always return the client
principal when KRB5_KDC_ERR_C_PRICIPAL_UNKNOWN is returned.

Check that this is really a referral by testing that the returned
client realm differs from the requested one.

Signed-off-by: Simo Sorce <simo@redhat.com>

When a FILE ccache method returns an error, append the filename to the
standard message for the code.  Remove code to set extended messages
in helper functions as they would just be overwritten.

Also change the interpretation of errno values.  Treat ENAMETOOLONG as
KRB5_FCC_NOFILE instead of KRB5_FCC_INTERNAL, since it has an external
cause and a name that long can't be opened by normal means.  Treat
EROFS as KRB5_FCC_PERM.  Treat ENOTDIR and ELOOP as KRB5_FCC_NOFILE
instead of KRB5_FCC_PERM as both errors imply that the full pathname
doesn't exist.  Treat EBUSY and ETXTBSY as KRB5_CC_IO instead of
KRB5_FCC_PERM as they indicate a conflict rather than a permission
issue.

[ghudson@mit.edu: renamed set_error to set_errmsg_filename; removed
now-inoperative code to set extended messages in helper functions;
trimmed changes to interpret_errno; clarified and shortened commit
message]

ticket: 8052 (new)

Linux 3.15 has added OFD locks, which contend with POSIX file locks
but are owned by the open file description instead of the process.
Use these in krb5_lock_file where available, for safer concurrency
behavior.

ticket: 8023 (new)

Support the err_fmt relation in [libdefaults] which allows custom
error message formatting.

[ghudson@mit.edu: maintain alphabetical order in documentation and
reword docs; simplify err_fmt_fmt; expand commit message]

ticket: 8047 (new)

Define internal names k5_prendmsg and k5_wrapmsg and use them where we
amend error messages.  This slightly changes the error message when we
fail to construct FAST AP-REQ armor, decrypt a FAST reply, or store
credentials in a gic_opts output ccache.  Adjust the test suite for
the latter of those changes.

[ghudson@mit.edu: define and use internal names for brevity; pull in
test fix from later commit; expand commit message; fix redundant
separators in LDAP messages]

ticket: 8046

Add four new public APIs for wrapping error messages:
krb5_prepend_error_message, krb5_vprepend_error_message,
krb5_wrap_error_message, and krb5_vwrap_error_message.  The first two
functions are from Heimdal and allow a prefix to be added to the
existing message for a code.  The latter two functions also allow the
code to be changed.

[ghudson@mit.edu: rename krb5_prepend_error_message2 to
krb5_wrap_error_message; clarify doxygen comments and put them in the
proper form; implement krb5_prepend_error_message in terms of
krb5_wrap_error_message; fix leak and null context handling in
krb5_wrap_error_message; rewrite commit message]

ticket: 8046 (new)

Implementations of fdopen() are inconsistent about the state of
the file offset after fdopen(., "a+") -- some position the stream
at the end of the file immediately (e.g., Solaris), for both reading
and writing, but others let reads occur from the beginning of the
file (e.g., glibc).

As it turns out, we only ever write to the file descriptor, not
through stdio, so opening the file with O_APPEND and using fdopen()
with "r+b" should give us sufficient append semantics, while
more portably letting the stream read from the beginning of the file.

This fixes the test suite on Solaris, a regression introduced
by commit 6979ead5e5c24ca0ec3569eb4bef48c2e5d8a726.

ticket: 8026

When duplicate suppression was requested, we would enter an
infinite loop upon encountering a duplicate entry, a bug
introduced in commit 0918990bf1d8560d74473fc0e41d08d433da1a15
and thus present in release 1.13.

Rework the conditional to avoid the loop, at the expense of
additional indentation for some of the code.

Ticket: 8038
tags: pullup
target_version: 1.13.1

If we fail to open the cache file in fcc_initialize, we could wind up
calling close(-1) which is harmless but incorrect.  Avoid this by
initializing fd and conditionalizing its cleanup.

ticket: 8026

gcc 4.6.3 (present in Ubuntu 12.04) is smart enough to look at
get_size and see that it does not always assign to *size_out, but not
smart enough to figure out that it always assigns to *size_out when it
returns 0.  As a result, it outputs two warnings which we treat as
errors.  Add an initial assignment to *size_out at the beginning of
get_size to work around this.

ticket: 8026