The realloc in my_fgetln was trying to grow the pointer to the string
buffer, not the string buffer itself.

In function 'my_fgetln',
    inlined from 'mit_prop_dump' at crypto/heimdal/kdc/mit_dump.c:156:19:
crypto/heimdal/kdc/mit_dump.c:119:13: error: 'realloc' called on unallocated object 'line' [-Werror=free-nonheap-object]
  119 |         n = realloc(buf, *sz + (*sz >> 1));
      |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
crypto/heimdal/kdc/mit_dump.c: In function 'mit_prop_dump':
crypto/heimdal/kdc/mit_dump.c:139:11: note: declared here
  139 |     char *line = NULL;
      |           ^~~~

Reviewed by:	rmacklem, cy
Fixes:		a93e1b731ae4 ("heimdal-kadmin: Add support for the -f dump option")
Differential Revision:	https://reviews.freebsd.org/D54933

This fixes a warning reported by GCC 14 on stable/14:

crypto/heimdal/lib/hdb/keys.c:241:13: warning: 'free' called on pointer 'ext' with nonzero offset 16 [-Wfree-nonheap-object]
  241 |             free(hist_keys);
      |             ^~~~~~~~~~~~~~~
crypto/heimdal/lib/hdb/keys.c:234:15: note: returned from 'calloc'
  234 |         ext = calloc(1, sizeof (*ext));
      |               ^~~~~~~~~~~~~~~~~~~~~~~~

Reviewed by:	rmacklem, cy
Fixes:		5000d023a446 ("heimdal-kadmin: Add support for the -f dump option")
Differential Revision:	https://reviews.freebsd.org/D54932

This fixes the build with GCC 14 on stable/14 which raises fatal
-Wimplicit-function-declaration warnings.

Reviewed by:	rmacklem, cy
Fixes:		5000d023a446 ("heimdal-kadmin: Add support for the -f dump option")
Differential Revision:	https://reviews.freebsd.org/D54931

Commit 5000d023a446 added a new flag to the dump option.

This patch documents this new flag.

This is a content change.

MFC after: 3 days
Fixes:	5000d023a446 ("heimdal-kadmin: Add support for the -f dump option")

The "-f" dump option allows a dump of the Heimdal
KDC in a format that the MIT kdb5_util command can
load into a MIT KDC's database.
This makes transitioning from the Heimdal KDC to
the current MIT one feasible without having to
re-create the KDC database from scratch.

glebius@ did the initial work, cherry picking these
commits from the Heimdal sources on github and then doing
extensive merge conflict resolution and other fixes so
that it would build.
Heimdal commit fca5399 authored by Nico Williams:
Initial commit for second approach for multiple kvno.  NOT TESTED!

Heimdal commit 57f1545 authored by Nico Williams:
Add support for writing to KDB and dumping HDB to MIT KDB dump format
    Before this change Heimdal could read KDBs.  Now it can write to
    them too.

    Heimdal can now also dump HDBs (including KDBs) in MIT format,
    which can then be imported with kdb5_util load.

    This is intended to help in migrations from MIT to Heimdal by
    allowing migrations from Heimdal to MIT so that it is possible
    to rollback from Heimdal to MIT should there be any issues.  The
    idea is to allow a) running Heimdal kdc/kadmind with a KDB, or
    b) running Heimdal with an HDB converted from a KDB and then
    rollback by dumping the HDB and loading a KDB.

    Note that not all TL data types are supported, only two: last
    password change and modify-by.  This is the minimum necessary.
    PKINIT users may need to add support for KRB5_TL_USER_CERTIFICATE,
    and for databases with K/M history we may need to add KRB5_TL_MKVNO
    support.

This resulted in a Heimdal kadmin that would dump
the KDC database in MIT format.  However, there
were issues when this dump was loaded into the
current MIT KDC in FreeBSD current/15.0.

The changes I did to make the dump more useful are listed below:
When "-f MIT" is used for "kadmin -l dump" it writes
the dump out in MIT format.  This dump format is understood
by the MIT kdb5_util command.  The patch modifies the above
so that the MIT KDC's master key keytab file can be provided
as the argument to "-f" so that the principals are re-encrypted in
it. This allows any principal with at least one strong encryption
type key to work without needing a change_password.
The strong encryption types supported by the Heimdal KDC are:
aes256-cts-hmac-sha1-96
aes128-cts-hmac-sha1-96

The issues my changes address are:
- If there are weak encryption keys in a principal's entry,
  MIT's kadmin.local will report that the principcal's entry
  is incomplete or corrupted.
- The keys are encrypted in Heimdal's master key.  The
  "-d" option can be used on the "kadmin -l dump" to
  de-encrypt them, but the passwords will not work on the
  current MIT KDC.

To try and deal with the above issues, this patch modied the above to:
- Does not dump the weak keys.
- Re-encrypts the strong keys in MIT's master key if the argument
  to "-f" is actually a filename which holds the MIT KDC's
  master key keytab and not "MIT".
- For principals that only have weak keys, it generates
  a fake strong key. This key will not work on the MIT
  KDC, but the principal entry will work once a
  change_password is done to it.
- It always generates a "modified_by" entry, faking one if
  not already present in the Heimdal KDC database.
  This was necessary, since the MIT kadmin will
  report that the principal entry is "incomplete or
  corrupted" without one.

It also fixed a problem where "get principal" no longer
worked after the initial patch was applied.

A man page update will be done as a separate commit.

I believe this commit is acceptable since the Heimdal
sources are now essentially deprecated in favor of the
MIT sources and that this new "-f" patch simplifies
the transition to the MIT KDC.

Discussed with:	glebius, cy
MFC after:	3 days

Patch supplied by mi@ through a private email.

Bump __FreeBSD_version for ports that might need this.

PR:		280025
MFC after	1 week

This fixes a clang 19 warning:

crypto/heimdal/lib/krb5/deprecated.c:75:17: error: comparison of different enumeration types ('krb5_keytype' (aka 'enum ENCTYPE') and 'enum krb5_keytype_old') [-Werror,-Wenum-compare]
   75 |     if (keytype != KEYTYPE_DES || context->etypes_des == NULL)
      |         ~~~~~~~ ^  ~~~~~~~~~~~

In https://github.com/heimdal/heimdal/commit/3bebbe5323 this was solved
by adding a cast. That commit is rather large, so I'm only applying the
one-liner here.

MFC after:	3 days

This is a residual of the $FreeBSD$ removal.

MFC After: 3 days (though I'll just run the command on the branches)
Sponsored by: Netflix

Fix build when WITH_OPENLDAP defined.

PR:		278430
Obtained from:	Upstream c1c7da7f79

Import upstream 6747e1628:

  asn1: Use unsigned bitfields for named bitsets

  Signed 1-bit bitfields are undefined in C.

This should fix the following warnings, which for unknown reasons are
errors in CI:

  /usr/src/crypto/heimdal/lib/hx509/ca.c:1020:22: warning: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Wsingle-bit-bitfield-constant-conversion]
   1020 |         ku.digitalSignature = 1;
        |                             ^ ~
  /usr/src/crypto/heimdal/lib/hx509/ca.c:1021:21: warning: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Wsingle-bit-bitfield-constant-conversion]
   1021 |         ku.keyEncipherment = 1;
        |                            ^ ~
  /usr/src/crypto/heimdal/lib/hx509/ca.c:1028:17: warning: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Wsingle-bit-bitfield-constant-conversion]
   1028 |         ku.keyCertSign = 1;
        |                        ^ ~
  /usr/src/crypto/heimdal/lib/hx509/ca.c:1029:13: warning: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Wsingle-bit-bitfield-constant-conversion]
   1029 |         ku.cRLSign = 1;
        |                    ^ ~

PR:		276960
Fixes:		1b7487592987
MFC after:	1 week