I'd like to continue the discussion of tlog integration, and also present you
the first release of tlog - a development preview, which has the configuration
interface necessary to implement the integration:
You're more than welcome to download RPMs, install, read tlog-rec(8) and
tlog-rec.conf(5), and experiment! Building from the Git tree and the tarball
works as well, if you're so inclined. I'm also attaching those manpages for
Here are the integration plans so far, as discussed with Jakub on our
devconf.cz trip meetings and before on the list. Jakub, please correct me or
* We follow the route similar to that taken by SELinux rule control
implementation . I.e. store the configuration in LDAP HBAC rules,
write to files on the client side and then specify them to tlog upon user
However, I'm also rather fond of the idea of specifying the whole
configuration through an environment variable instead of through a file
referenced by an environment variable - it's not big at all, and we'll avoid
the hassle of managing the files.
I implemented support for both in tlog (was easy).
* We'll have to make nss_sss report user's shell as tlog-rec (how?) and
specify the actual shell to tlog-rec via an environment variable, through
pam_sss (with SSS_PAM_ENV_ITEM messages). I.e.:
* Nss_sss would always report tlog-rec as the user's shell.
* During login (e.g. through "login" or "sshd") pam_sss would add a variable
to the user environment, containing, or pointing at, a tlog-rec
configuration (TLOG_REC_CONF_TEXT or TLOG_REC_CONF_FILE). That
configuration would contain the user's actual shell. I can also implement
support for a separate variable just for the shell (TLOG_REC_SHELL?) to
simplify the implementation for the start.
* Tlog-rec would read the system-wide configuration and overlay it with the
one specified in the environment, adding the specific user shell, and then
would spawn it.
Please also see the draft integration design page  for reference.
I hope to refine and extend it in the coming weeks to match FreeIPA standards.
Please chime in and suggest, object, discuss!
Also, please report tlog bugs at https://github.com/spbnick/tlog/issues
Please find attached proof-of-concept patches for a part of NSS integration
with tlog. Namely, addition of shell substitution for getpwnam requests.
The code is supposed to replace a user's shell with /usr/bin/tlog-rec, if
session recording is enabled for all users, if it is enabled for that
particular user, or for a group that it belongs to.
The configuration is done in a dedicated section of sssd.conf named
"session_recording", which can contain three options "scope", "users", and
"groups". Those correspond to the scope of session recording: "none", "some",
and "all", corresponding in order to: disabled session recording, session
recording enabled for the specified users/groups, and session recording
enabled for all users handled by SSSD.
An example of a configuration can be:
scope = none
; Enabled for everyone
scope = all
; Enabled for some users and groups
scope = some
users = user1, user2
groups = group1, group2
The parts to be done still are adding support for getpwuid and getpwent
requests, exporting of the original shell in pam_sss, and of course cleaning
it up and doing it according to your comments and requirements.
The code has some documentation in doxygen format, which I can change later if
we decide on some other format, or no documentation at all.
Please, tell me if I'm doing anything wrong this far already, or suggest
better ways to do it.
P.S. I'm on PTO for two weeks starting next week, so might not be able to
the attached patches implement unit tests for the pam_sss module using
pam_wrapper and libpamtest. In my testing, the coverage is around 75%
with mostly the parts that require running as root being untested.
I worked on this patchset even though the features for 1.14 are in full
swing because there are several tickets that will require us to patch
pam_sss, so it's important to have the code that changes tested. In
addition, when we merge Dan's patches to use TLS with integration tests,
then we'll be able to also test authentication in integration tests
easily using libpamtest-python.
However, our CI fails for me constantly:
The strange thing is that running CI locally works fine and so does make
check. Can anyone help point me in the right direction as to what should
I check next? I suspect some of the environment variables might not be
set correctly, but I don't see why..
I am solving ticket  now. There are three
points mentioned. A have prepared patches for
the first two. I would like to ask anybody it
is right or if I miss something.
The third point is about full LDIFF in special
debug level. What does it mean 'special debug
level'? Is it new option, for example?
this is my suggestion to solve https://fedorahosted.org/sssd/ticket/2948
"Handle overriden name of members in the memberUid attribute".
The first two patches are for the IPA provider and make sure that all
ghost members in a group get resolved because otherwise we cannot
determine if the name is overridden or not. This adds an overhead to
group lookups, especially for larger groups but I think it is an
requirement which cannot be skipped.
The third patch adds a sysdb call to recursively resolve all
user-members of a group. Since the groups in SSSD's cache are
hierarchically organized the member attribute only contains direct
user and group members. To get all users the group members must be
Finally the forth patch applies the code-path which is already used for
non-default views to the default case as well and adds a new list of
members, with correctly overridden names (hopefully :-) which is then
used in fill_grmem(). This adds some overhead to the overall group
processing in the NSS responder (as can be seen in the test changes
because the members are returned in different order in some cases). But
I think because the of memory cache this is acceptable and might even
help to remove the memberuid attribute in future and make the memberof
I worked on an alternative approach as well which tried to make the
memberof plugin aware of the defaultOverrideName attribute. My wip tree
but so far it does not work properly. Additionally I would prefer to not
touch the memberof plugin.
I documented workflow that we could use for submitting PRs:
It's quite similar to what the FreeIPA team uses (although I don't think
they publicly document it yet).
Comments or edits welcome. If there are none, I'll link the page from
the Contribute page later.
I've suggested, a long time ago, that we could start making use of
GNULIB's compiler warnings from 'manywarnings' module. This is
basically what we have been doing in a few projects that I (used to
and still) maintain (like spice-gtk and libosinfo, for instance).
For now I didn't try to fix any of the warnings that we cannot cope
with, mainly because I'm not sure whether you guys will agree on using
it or not.
Here is an experimental patch that works properly on Fedora 24. I
still have to make some tests on RHEL-6, RHEL-7 and a few other
systems (Debian, at least) in order to make sure that we won't break
the build because of the patch.
If you are okay with the change, I'll start going through the warnings
that we cannot cope with and slowly start fixing them. Although, I
have the feeling that fixing some of them would cause a lot of
undesired changes, which will just bring troubles for ourselves when
backporting fixes downstream (and here I'm talking about
-Wformat-signedess, -Wsign-compare, -Wunused-parameter, ... for
I'm looking forward to hear some feedback!