systemd-cryptsetup supports a FIDO2 mode with manual parameters, where
the user provides all the information necessary for recreating the
secret, such as: credential ID, relaying party ID and the salt. This
feature works great for implementing 2FA schemes, where the salt file
is for example a secret unsealed from the TPM or some other source.
While the unlocking part is quite straightforward to set up, enrolling
such a keyslot - not so easy. There is no clearly documented
way on how to set this up and online resources are scarce on this topic
too. By implementing a straightforward way to enroll such a keyslot
directly from systemd-cryptenroll we streamline the enrollment process
and reduce chances for user error when doing such things manually.
DynamicUser= enables PrivateTmp= implicitly to avoid files owned by reusable uids
leaking into the host. Change it to instead create a fully private tmpfs instance
instead, which also ensures the same result, since it has less impactful semantics
with respect to PrivateTmp=yes, which links the mount namespace to the host's /tmp
instead. If a user specifies PrivateTmp manually, let the existing behaviour
unchanged to ensure backward compatibility is not broken.
Historically, systemd-tmpfiles was designed to manager temporary
files, but nowadays it has become a generic tool for managing
all kinds of files. To avoid user confusion, let's remove "temporary"
from the tool's description.
As discussed in #33349
The setting of systemd clock is important and deserves an accurate description,
see for example:
https://discussion.fedoraproject.org/t/f38-to-f39-40-dnf-system-upgrade-can-fail-on-raspberry-pi/92403https://bugzilla.redhat.com/show_bug.cgi?id=2242759
The meat of the description was in systemd-timesyncd.service(8), but
actually it's systemd that sets the clock. In particular, systemd-timesyncd
doesn't know anything about /usr/lib/clock-epoch, and since systemd sets
the clock to the epoch when initializing, systemd-timesyncd would only
get to advance the clock to the epoch under special circumstances.
Also, systemd-timesyncd is an optional component, so we can't even rely
on its man page being installed in all circumstances. The description needs
to be moved to systemd(1).
The description is updated to describe the changes that were made in
previous commits.
Mention that by default, /home is managed by tmpfiles.d/home.conf, and
recommend that users run systemd-tmpfiles --dry-run --purge first to
see exactly what will be removed.
When in FIDO2 mode with manual parameters, i.e. when not reading the
parameters off the LUKS2 header, the current behavior in regards to PIN,
UP and UV features is to default to v248 logic, where we use PIN + UP
when needed, and do not configure UV at all. Let's allow users to
configure those features in manual mode too.
For putting together "varlinkctl call" command lines it's useful to
quickly enumerate all methods implemented by a service. Hence, let's add
a new "list-methods" which uses the introspection data of a service to
quickly list methods.
This is implemented as a special flavour of the "introspect" logic,
and just suppresses all output except for the method names.
let's make it easier to use the introspection functionality of
"varlinkctl": if no interface name is shown, display the introspection
data of all available interfaces. Moreover, allow that multiple
interfaces can be listed, in which case we enumerate them all.
This relieves the user from having to list interfaces first in order to
find the ones which to introspect.
I find myself wanting to check this data with a quick command, and
browsing through /sys/ manually getting binary data sucks. Hence let's
do add a nice little analysis tool.
Multipath TCP (MPTCP), standardized in RFC8684 [1], is a TCP extension
that enables a TCP connection to use different paths. It allows a device
to make use of multiple interfaces at once to send and receive TCP
packets over a single MPTCP connection. MPTCP can aggregate the
bandwidth of multiple interfaces or prefer the one with the lowest
latency, it also allows a fail-over if one path is down, and the traffic
is seamlessly re-injected on other paths.
To benefit from MPTCP, both the client and the server have to support
it. Multipath TCP is a backward-compatible TCP extension that is enabled
by default on recent Linux distributions (Debian, Ubuntu, Redhat, ...).
Multipath TCP is included in the Linux kernel since version 5.6 [2]. To
use it on Linux, an application must explicitly enable it when creating
the socket:
int sd = socket(AF_INET(6), SOCK_STREAM, IPPROTO_MPTCP);
No need to change anything else in the application.
This patch allows MPTCP protocol in the Socket unit configuration. So
now, a <unit>.socket can contain this to use MPTCP instead of TCP:
[Socket]
SocketProtocol=mptcp
MPTCP support has been allowed similarly to what has been already done
to allow SCTP: just one line in core/socket.c, a very simple addition
thanks to the flexible architecture already in place.
On top of that, IPPROTO_MPTCP has also been added in the list of allowed
protocols in two other places, and in the doc. It has also been added to
the missing_network.h file, for systems with an old libc -- note that it
was also required to include <netinet/in.h> in this file to avoid
redefinition errors.
Link: https://www.rfc-editor.org/rfc/rfc8684.html [1]
Link: https://www.mptcp.dev [2]
Set the $REMOTE_ADDR environment variable for AF_UNIX socket connections
when using per-connection socket activation (Accept=yes). $REMOTE_ADDR
will now contain the remote socket's file system path (starting with a
slash "/") or its address in the abstract namespace (starting with an
at symbol "@").
This information is essential for identifying the remote peer in AF_UNIX
socket connections, but it's not easy to obtain in a shell script for
example without pulling in a ton of additional tools. By setting
$REMOTE_ADDR, we make this information readily available to the
activated service.
Since we document /usr/local/lib/systemd/ and other paths for various things,
add notes that this is not supported if /usr/local is a separate partition. In
systemd.unit, I tried to add the footnote in the table where
/usr/local/lib/systemd/ is listed, but that get's rendered as '[sup]a[/sup]'
with a mangled footnote at the bottom of the table :( .
Also, split paragraphs in one place where the subject changes without any
transition.
Follow-up for 02f35b1c90.
Replaces https://github.com/systemd/systemd/pull/33231.
Section "Description" didn't actually say what systemd does. And we had a giant
"Concepts" section that actually described units types and other details about
them. So let's move the basic description of functionality to "Description" and
rename the following section to "Units".
The link to the Original Design Document is moved to "See Also", it is of
historical interest mostly at this point.
The only actual change is that when talking about API filesystems, /dev is also
mentioned. (I think /sys+/proc+/dev are the canonical set and should be always
listed on one breath.)
It has been mentioned in IPv4Forwarding= and IPv6Forwarding=,
but let's also explain in the settings who imply these settings.
Follow-up for 3976c43092 and
485f5148b3.
For run0 (as opposed to systemd-run in general), connecting to
the system bus (of localhost or container) as a different user
than root and then trying to elevate privilege from that
makes little sense:
https://github.com/systemd/systemd/issues/32997#issuecomment-2127992973
The @ syntax is mostly useful when connecting to the user bus,
which is not a use case for run0. Hence, let's remove the example.
The syntax will be properly refused in #32999.
- mention that /run/machine-id is used if exist.
- mention system.machine_id credential,
- credential, VM uuid, and container uuid are not read when --root=
is specified or running in a chroot environment.
