logind: split %t directory creation to a helper unit
Unfortunately this needs a new binary to do the mount because there's just
too many special steps to outsource this to systemd-mount:
- EPERM needs to be treated specially
- UserRuntimeDir= setting must be obeyed
- SELinux label must be adjusted
This allows user@.service to be started independently of logind.
So 'systemctl start user@nnn' will start the user manager for user nnn.
Logind will start it too when the user logs in, and will stop it (unless
lingering is enabled) when the user logs out.
Use a dash-truncated drop-in for user-%j.slice configuration
This removes the UserTasksMax= setting in logind.conf. Instead, the generic
TasksMax= setting on the slice should be used. Instead of a transient unit we
use a drop-in to tweak the default definition of a .slice. It's better to use
the normal unit mechanisms instead of creating units on the fly. This will also
make it easier to start user@.service independently of logind, or set
additional settings like MemoryMax= for user slices.
The setting in logind is removed, because otherwise we would have two sources
of "truth": the slice on disk and the logind config. Instead of trying to
coordinate those two sources of configuration (and maintainer overrides to
both), let's just convert to the new one fully.
Right now now automatic transition mechanism is provided. logind will emit a
hint when it encounters the setting, but otherwise it will be ignored.
Those are quite similar to %i/%I, but refer to the last dash-separated
component of the name prefix.
The new functionality of dash-dropins could largely supersede the template
functionality, so it would be tempting to overload %i/%I. But that would
not be backwards compatible. So let's add the two new letters instead.
The description in the man page disagreed with the code. Let the code win,
since if anybody is using this, they are more likely to depend on actual
behaviour rather than the docs. (In Fedora workstation installation there's
only one use, and it doesn't make much sense either way: SyslogIdentifier=%N
in xfs_scrub@.service.)
Also adds dots at the end everywhere, because we have multiple sentences in
some explanations, so we need dots.
doc: add a bit more documentation about systemd and cgroups and cgroupsv2 and delegation
Ultimately we should replace the relevant wiki texts with documentation
maintained as part of our project tree. This is a start. It can't
replace the wiki documentation in full yet, but I think it's already
very useful.
terminal: add internal API to format URLs for display in capable terminals
Newer terminals (in particular gnome-terminal) understand special escape
sequence for formatting clickable links. Let's support that to make our
tool output more clickable where that's appropriate.
The one big issue is that 'less' currently doesn't grok this, and
doesn't ignore sequence like regular terminal implementations do if they
don't support it. Hence for now, let's disable URL output if a pager is
used. We should revisit that though as soon as less added support for it
and enough time passed for it to enter various distributions.
Double newlines (i.e. one empty lines) are great to structure code. But
let's avoid triple newlines (i.e. two empty lines), quadruple newlines,
quintuple newlines, …, that's just spurious whitespace.
It's an easy way to drop 121 lines of code, and keeps the coding style
of our sources a bit tigther.
mkosi: drop dumping all test output to console again
As it appears meson's test cases nowadays (?) show useful logs for
failing tests anyway, hence there's no need to show them unconditionally
in full every time anymore. Let's hence simplify and drop this.
This makes `resolvectl` use the verb style command line, e.g.,
`resolvectl status` or `resolvectl tlsa tcp fedoraproject.org:443`.
For compatibility, if the invocation name is `systemd-resolve`,
then it accepts the old syntax, e.g. `systemd-resolve --status`.
First of all, it's frickin' ugly and wrong, as IPC sockets should be
placed in /run and definitely not under a guessable name under
world-writable /tmp. Secondly, it can't even work as we set
PrivateTmp=yes on the service.
Hence, let's clean up the example, and simply use a socket in /run
instead.
namespace: rework how we resolve symlinks in mount points
Before this patch we'd resolve all symlinks of bind mounts and other
mount points to establish for a service in advance, and only then start
mounting them. This is problematic, if symlink chains jump around
between directories in a namespace tree, so that to resolve a specific
symlink chain we need to establish another mount already. A typical case
where this happens is if /etc/resolv.conf is a symlink to some file in
/run: in that case we'd normally resolve and mount /etc/resolv.conf
early on, but that's broken, as to do this properly we'd need to resolve
/etc/resolv.conf first, then figure out that /run needs to be mounted
before we can proceed, and thus reorder the order in which we apply
mounts dynamically.
With this change, whenever we are about to apply a mount, we'll do a
single step of the symlink normalization process, patch the mount entry
accordingly, and then sort the list of mounts to establish again, taking
the new path into account. This means that we can correctly deal with
the example above: we might start with wanting to mount /etc/resolv.conf
early, but after resolving it to the path in /run/ we'd push it to the
end of the list, ensuring that /run is mounted first.
(Note that this also fixes another bug: we were following symlinks on
the bind mount source relative to the root directory of the service,
rather than of the host. That's wrong though as we explicitly document
tha the source of bind mounts is always on the host.)
We have plenty of code in our codebase that outputs tables to the
console, and all is homegrown and awful. Let's replace it with a generic
implementation that can do automatically what the old implementations
did manually.
pager.[ch] doesn't use any APIs from src/libsystemd/ or src/shared/
hence there's no reason for it to be in src/shared/, let's move it to
src/basic/ instead.
This enables us to use pager.[ch] APIs from other code in src/basic/,
for example pager_have() and suchlike.
1. Ellipsation to 0, 1 or 2 characters is now supported. Previously we'd
hit an assert if the new lengths was < 3, this is now permitted. The
result strings won't show too much info still of course, but the code
becomes a bit more generic and robust to use.
2. If a UTF-8 mode is disabled and the input string is pure ASCII, then
"..." is used for ellipsation, otherwise (as before) "…". This means
on a pure-ASCII system we should remain pure-ASCII, matching
behaviour otherwise exposed with special_glyph() and friends. Note
that we'll use "…" for ellipsiation as soon as either the locale
settings indicate an UTF-8 mode or the input string already contains
non-ASCII unicode characters.
man: add a new page with a general description of common syntax
We have a common parser, but for the user it might be
completely unobvious that the same general rules apply
to all those files. Let's add a page about the basic syntax
so that the more specific pages don't have to repeat those
details.
path-util: Finish DEFAULT_PATH_NULSTR with an extra NUL (#8745)
The NULSTR_FOREACH iterator needs to see an empty string at the end, so
we need to insert an extra NUL explicitly.
Also update PATH0_BIN_SBIN(x) to include an extra NUL terminator, rename
it to PATH_BIN_SBIN_NULSTR(x), which is more consistent with the similar
CONF_PATHS_NULSTR(x) macro.
timesync: establish connection when network become online and the manager is not connected yet (#8727)
This also introduces `manager_is_connected()` helper function, which
returns true when the manager is sending a request, resolving a server
name, or in a poll interval.
1. Don't unnecessarily export functions we don't call outside of
machined.c
2. Use cleanup logic for the manager object.
3. Propagate errors properly from manager_new(). So far if
sd_event_new() returns EMFILE/ENFILE for some reason we would have
logged that as log_oom(), which isn#t right, really.
4. Handle SIGTERM/SIGINT cleanly. It's easy, and prettier then letting
the kernel just abort us. It also makes it possible to valgrind
machined properly.
networkd: fix dhcp4 link without routes not being considered ready (#8728)
The dhcp4 code sets link->dhcp4_configured when dhcp4_route_handler()
has processed the last message.
However, in case UseRoutes=no has been set in the [DHCP] section, or
in case the DHCP server simply sends no routes, link_set_dhcp_routes()
will not send any netlink messages and dhcp4_route_handler() will
therefore never be called.
This causes the link to never reach LINK_STATE_CONFIGURED, and e.g.
systemd-networkd-wait-online will not consider the link as ready.
Fix that by setting link->dhcp4_configured = true and calling
link_check_ready() in dhcp4_address_handler() in case
link_set_dhcp_routes() sent no netlink messages (dhcp4_messages is
zero).
networkd: fix crash if fails to get network file (#8714)
In some situation if networkd fails to get the network file
then networkd crashes becasse the link->network is not initalized;
```
veth99: Failed to get network dhcp-client-ipv4-only: No such file or directory
Segmentation fault
gdb) r
The program being debugged has been started already.
Start it from the beginning? (y or n) y
Starting program: /home/sus/tt/systemd/build/systemd-networkd
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
warning: Loadable section ".note.gnu.property" outside of ELF segments
warning: Loadable section ".note.gnu.property" outside of ELF segments
warning: Loadable section ".note.gnu.property" outside of ELF segments
Program received signal SIGSEGV, Segmentation fault.
link_load (link=0x55555582ccd0) at ../src/network/networkd-link.c:2973
2973 r = sd_dhcp_client_new(&link->dhcp_client, link->network->dhcp_anonymize);
(gdb) bt
(gdb) p link->network
$1 = (Network *) 0x0
(gdb) list
2968 if (r < 0) {
2969 log_link_debug_errno(link, r, "Failed to parse DHCPv4 address %s: %m", dhcp4_address);
2970 goto dhcp4_address_fail;
2971 }
2972
2973 r = sd_dhcp_client_new(&link->dhcp_client, link->network->dhcp_anonymize);
2974 if (r < 0)
2975 return log_link_error_errno(link, r, "Failed to create DHCPv4 client: %m");
2976
2977 r = sd_dhcp_client_set_request_address(link->dhcp_client, &address.in);
(gdb) r
```