This change adds plugin support to the kadmin libraries for performing
actions before and after a password change is committed to the KDC database
and after a change is made to the attributes of a principal (specifically,
a change to DISALLOW_ALL_TIX).
This change adds a hook_libraries configuration option to the [kadmin]
section of krb5.conf (or kdc.conf if you use that file) that must be set
to load the module. That configuration option is in the form:
[kadmin]
hook_libraries = /usr/local/lib/krb5/plugins/kadm5_hook/krb5_sync.so
where the value is the full path to the plugin that you want to load. If
this option is not present, kadmind will not load a plugin and the changes
from the patch will be inactive. If this option is given and the plugin
cannot be loaded, kadmind startup will abort with a (hopefully useful)
error message in syslog.
Any plugin used with this patch must expose a public function named
kadm5_hook_init of type kadm5_hook_init_t that returns a kadm5_hook structure.
See sample_hook.c for an example of this initialization function.
typedef struct kadm5_hook {
const char *name;
uint32_t version;
const char *vendor;
void (KRB5_CALLCONV *fini)(krb5_context, void *data);
krb5_error_code (KRB5_CALLCONV *chpass)(krb5_context context,
void *data,
enum kadm5_hook_stage stage,
krb5_error_code code,
krb5_const_principal princ,
uint32_t flags,
size_t n_ks_tuple,
krb5_key_salt_tuple *ks_tuple,
const char *password,
char **error_msg);
...
};
where enum kadm5_hook_stage is:
enum kadm5_hook_stage {
KADM5_HOOK_STAGE_PRECOMMIT,
KADM5_HOOK_STAGE_POSTCOMMIT
};
init creates a hook context that is passed into all subsequent calls.
chpass is called for password changes, create is called for principal
creation (with the newly-created principal in the kadm5_principal_ent_t
argument), and modify is called when a principal is modified. The purpose of
the remaining functions should be self-explanatory.
returning 0 on success and a Kerberos error code on failure, setting the
Kerberos error message in the provided context. The error code passed in is
valid for post-commit hooks and contains the result of the update operation.
This change is submitted under the following license
Copyright 2012, 2013
The Board of Trustees of the Leland Stanford Junior University
Portions Copyright 2018 AuriStor Inc.
Copying and distribution of this file, with or without modification, are
permitted in any medium without royalty provided the copyright notice and
this notice are preserved. This file is offered as-is, without any
warranty.
When new keys are added (typically via kadm5_setkey_principal_3),
truncate the key history to remove old keys, that is keys older than
the newest key which was in effect prior longer ago than the principal's
maximum ticket lifetime. This feature is controlled via the "[kadmin]"
section's "prune-key-history" boolean parameter, which defaults to false.
Currently this happens only when kadm5_setkey_principal_3()
is called directly on the server, the client API simulates
kadm5_setkey_principal_3() via a get, update, modify sequence that does
not prune the key history. The plan is to add a new kadm5 protocol RPC
and convert clients to call that instead.
In setkey_principal_3 seal keys after entry key update
Also, for now, don't check the return value of kadm5_log_modify() in
the new kadm5_s_setkey_principal_3(). This has to be addressed more
globally.
Censor stale keys in kadm5_s_get_principal
We turn on a few extra warnings and fix the fallout that occurs
when building with --enable-developer. Note that we get different
warnings on different machines and so this will be a work in
progress. So far, we have built on NetBSD/amd64 5.99.64 (which
uses gcc 4.5.3) and Ubuntu 10.04.3 LTS (which uses gcc 4.4.3).
Notably, we fixed
1. a lot of missing structure initialisers,
2. unchecked return values for functions that glibc
marks as __attribute__((warn-unused-result)),
3. made minor modifications to slc and asn1_compile
which can generate code which generates warnings,
and
4. a few stragglers here and there.
We turned off the extended warnings for many programs in appl/ as
they are nearing the end of their useful lifetime, e.g. rsh, rcp,
popper, ftp and telnet.
Interestingly, glibc's strncmp() macro needed to be worked around
whereas the function calls did not.
We have not yet tried this on 32 bit platforms, so there will be
a few more warnings when we do.
The libkadm5 functions hdb_open() and close around all HDB ops. This
meant the previous implementation of kadm5_lock() and unlock would
always result in a core dump. Now we hdb_open() for write in
kadm5_lock() and hdb_close() in kadm5_unlock(), with all kadm5_s_*()
functions now not opening nor closing the HDB when the server context
keep_open flag is set.
Also, there's now kadmin(8) lock and unlock commands. These are there
primarily as a way to test the kadm5_lock()/unlock() operations, but
MIT's kadmin.local also has lock/unlock commands, and these can be
useful for scripting (though they require much care).
ctx->config.realm can be NULL, check for that, from Bjorn S.
git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@21413 ec53bebd-3082-4978-b11e-865c3cabbd6b
config parameters, try to figure out these if they're not provided
git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@7326 ec53bebd-3082-4978-b11e-865c3cabbd6b