safe_close() automatically becomes a NOP when a negative fd is passed,
and returns -1 unconditionally. This makes it easy to write lines like
this:
fd = safe_close(fd);
Which will close an fd if it is open, and reset the fd variable
correctly.
By making use of this new scheme we can drop a > 200 lines of code that
was required to test for non-negative fds or to reset the closed fd
variable afterwards.
Simplify the shutdown logic a bit:
- Keep the session FIFO around in the PAM module, even after the session
shutdown hook has been finished. This allows logind to track precisely
when the PAM handler goes away.
- In the ReleaseSession() call start a timer, that will stop terminate
the session when elapsed.
- Never fiddle with the KillMode of scopes to configure whether user
processes should be killed or not. Instead, simply leave the scope
units around when we terminate a session whose processes should not be
killed.
- When killing is enabled, stop the session scope on FIFO EOF or after
the ReleaseSession() timeout. When killing is disabled, simply tell
PID 1 to abandon the scope.
Because the scopes stay around and hence all processes are always member
of a scope, the system shutdown logic should be more robust, as the
scopes can be shutdown as part of the usual shutdown logic.
This is initialized from XDG_SESSION_DESKTOP and is useful for GNOME
to recognize its own sessions. It's supposed to be set to a short string
identifying the session, such as "kde" or "gnome".
Fix the whole code to use "unsigned int" for vtnr. 0 is an invalid vtnr so
we don't need negative numbers at all.
Note that most code already assumes it's unsigned so in case there's a
negative vtnr, our code may, under special circumstances, silently break.
So this patch makes sure all sources of vtnrs verify the validity. Also
note that the dbus api already uses unsigned ints.
It's better not to set any XDG_RUNTIME_DIR at all rather than one of a
different user. So let's do this.
This changes the bus call parameters of CreateSession(), but that is
explicitly an internal API hence should be fine. Note however, that a
logind restart (the way the RPM postinst scriptlets do it) is necessary
to make things work again.
systemd_pam would ignore all params after the first invalid one.
Instead ignore just this one, and parse the rest. There's just
one now, but as a matter of principle ;)
Also, allow debug as an alias for debug=1, and don't treat
invalid debug= options as fatal.
systemd-logind will start user@.service. user@.service unit uses
PAM with service name 'systemd-user' to perform account and session
managment tasks. Previously, the name was 'systemd-shared', it is
now changed to 'systemd-user'.
Most PAM installations use one common setup for different callers.
Based on a quick poll, distributions fall into two camps: those that
have system-auth (Redhat, Fedora, CentOS, Arch, Gentoo, Mageia,
Mandriva), and those that have common-auth (Debian, Ubuntu, OpenSUSE).
Distributions that have system-auth have just one configuration file
that contains auth, password, account, and session blocks, and
distributions that have common-auth also have common-session,
common-password, and common-account. It is thus impossible to use one
configuration file which would work for everybody. systemd-user now
refers to system-auth, because it seems that the approach with one
file is more popular and also easier, so let's follow that.
In order to prepare things for the single-writer cgroup scheme, let's
make logind use systemd's own primitives for cgroup management.
Every login user now gets his own private slice unit, in which his sessions
live in a scope unit each. Also, add user@$UID.service to the same
slice, and implicitly start it on first login.
Before, we would initialize many fields twice: first
by filling the structure with zeros, and then a second
time with the real values. We can let the compiler do
the job for us, avoiding one copy.
A downside of this patch is that text gets slightly
bigger. This is because all zero() calls are effectively
inlined:
$ size build/.libs/systemd
text data bss dec hex filename
before 897737 107300 2560 1007597 f5fed build/.libs/systemd
after 897873 107300 2560 1007733 f6075 build/.libs/systemd
… actually less than 1‰.
A few asserts that the parameter is not null had to be removed. I
don't think this changes much, because first, it is quite unlikely
for the assert to fail, and second, an immediate SEGV is almost as
good as an assert.
It is possible to build systemd without logind or run logind without systemd
init. Commit 66e41181 fixed sd_booted() to only succeed for systemd init; with
that, testing for systemd init is wrong in the parts that talk to logind.
In particular, this affects the PAM module and the "uaccess" udev builtin.
Change sd_booted() to a new logind_running() which tests for
/run/systemd/seats/.
For details, see:
<https://mail.gnome.org/archives/desktop-devel-list/2013-March/msg00092.html>
https://bugs.freedesktop.org/show_bug.cgi?id=62754
We finally got the OK from all contributors with non-trivial commits to
relicense systemd from GPL2+ to LGPL2.1+.
Some udev bits continue to be GPL2+ for now, but we are looking into
relicensing them too, to allow free copy/paste of all code within
systemd.
The bits that used to be MIT continue to be MIT.
The big benefit of the relicensing is that closed source code may now
link against libsystemd-login.so and friends.
For clean session endings ask logind explicitly to get rid of the FIFO
before closing it so that the FIFO logic doesn't result in su/sudo to be
terminated immediately.
This introduces the new PAM environment variable XDG_SESSION_CLASS. If
not set, defaults to "user".
This is useful for apps that want to distuingish real user logins from
"fake" ones which just exist to show a gdm login screen or a lock
screen.
