mirror of
https://salsa.debian.org/freeipa-team/freeipa.git
synced 2024-12-24 08:00:02 -06:00
3f1b373cb2
Since November 2020, Active Directory KDC generates a new type of signature as part of the PAC. It is called "ticket signature", and is generated based on the encrypted part of the ticket. The presence of this signature is not mandatory in order for the PAC to be accepted for S4U requests. However, the behavior is different for MIT krb5. Support was added as part of the 1.20 release, and this signature is required in order to process S4U requests. Contrary to the PAC extended KDC signature, the code generating this signature cannot be isolated and backported to older krb5 versions because this version of the KDB API does not allow passing the content of the ticket's encrypted part to IPA. This is an issue in gradual upgrade scenarios where some IPA servers rely on 1.19 and older versions of MIT krb5, while others use version 1.20 or newer. A service ticket that was provided by 1.19- IPA KDC will be rejected when used by a service against a 1.20+ IPA KDC for S4U requests. On Fedora, CentOS 9 Stream, and RHEL 9, when the krb5 version is 1.20 or newer, it will include a downstream-only update adding the "optional_pac_tkt_chksum" KDB string attribute allowing to tolerate the absence of PAC ticket signatures, if necessary. This commit adds an extra step during the installation and update processes where it adds a "pacTktSignSupported" ipaConfigString attribute in "cn=KDC,cn=[server],cn=masters,cn=ipa,cn=etc,[basedn]" if the MIT krb5 version IPA what built with was 1.20 or newer. This commit also set "optional_pac_tkt_chksum" as a virtual KDB entry attribute. This means the value of the attribute is not actually stored in the database (to avoid race conditions), but its value is determined at the KDC starting time by search the "pacTktSignSupported" ipaConfigString in the server list. If this value is missing for at least of them is missing, enforcement of the PAC ticket signature is disabled by setting "optional_pac_tkt_chksum" to true for the local realm TGS KDB entry. For foreign realm TGS KDB entries, the "optional_pac_tkt_chksum" virtual string attribute is set to true systematically, because, at least for now, trusted AD domains can still have PAC ticket signature support disabled. Given the fact the "pacTktSignSupported" ipaConfigString for a single server is added when this server is updated, and that the value of "optional_pac_tkt_chksum" is determined at KDC starting time based on the ipaConfigString attributes of all the KDCs in the domain, this requires to restart all the KDCs in the domain after all IPA servers were updated in order for PAC ticket signature enforcement to actually take effect. Fixes: https://pagure.io/freeipa/issue/9371 Signed-off-by: Julien Rische <jrische@redhat.com> Reviewed-By: Rob Crittenden <rcritten@redhat.com> Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com> |
||
|---|---|---|
| .. | ||
| install | ||
| __init__.py | ||
| admintool.py | ||
| certdb.py | ||
| config.py | ||
| cookie.py | ||
| directivesetter.py | ||
| dn_ctypes.py | ||
| dn.py | ||
| dnsutil.py | ||
| dogtag.py | ||
| errors.py | ||
| fqdn.py | ||
| graph.py | ||
| ipa_log_manager.py | ||
| ipachangeconf.py | ||
| ipaldap.py | ||
| ipautil.py | ||
| ipavalidate.py | ||
| kerberos.py | ||
| kernel_keyring.py | ||
| Makefile.am | ||
| nsslib.py | ||
| README | ||
| session_storage.py | ||
| setup.cfg | ||
| setup.py | ||
| ssh.py | ||
| version.py.in | ||
This is a set of libraries common to IPA clients and servers though mostly
geared currently towards command-line tools.
A brief overview:
config.py - identify the IPA server domain and realm. It uses python-dns to
try to detect this information first and will fall back to
/etc/ipa/default.conf if that fails.
ipautil.py - helper functions
entity.py - entity is the main data type. User and Group extend this class
(but don't add anything currently).
ipavalidate.py - basic data validation routines