Will be used by nftables nfnetlink backend.
It sends a series of netlink messages that form a nftables
update transaction.
The transaction will then generate a series of ack messages
(or an error).
This function will be used to read these acks.
nftables uses a transaction-based netlink model: one netlink write
comes with multiple messages.
A 'BEGIN' message to tell nf_tables/kernel that a new transaction starts.
Then, one more messages to add/delete tables/chains/rules etc.
Lastly, an END message that commits all changes.
This function will be used to send all the individual messages that should
make up a single transaction as a single write.
add nfnetlink_nftables helper functions to:
* open a new nfnetlink socket to kernel
* add tables, chains, rules, sets and maps
* delete/flush table
* add and delete elements from sets/maps
This is unfortunately harder to implement than it sounds. The user's bus
is bound a to the user's lifecycle after all (i.e. only exists as long
as the user has at least one PAM session), and the path dynamically (at
least theoretically, in practice it's going to be the same always)
generated via $XDG_RUNTIME_DIR in /run/.
To fix this properly, we'll thus go through PAM before connecting to a
user bus. Which is hard since we cannot just link against libpam in the
container, since the container might have been compiled entirely
differently. So our way out is to use systemd-run from outside, which
invokes a transient unit that does PAM from outside, doing so via D-Bus.
Inside the transient unit we then invoke systemd-stdio-bridge which
forwards D-Bus from the user bus to us. The systemd-stdio-bridge makes
up the PAM session and thus we can sure tht the bus exists at least as
long as the bus connection is kept.
Or so say this differently: if you use "systemctl -M lennart@foobar"
now, the bus connection works like this:
1. sd-bus on the host forks off:
systemd-run -M foobar -PGq --wait -pUser=lennart -pPAMName=login systemd-stdio-bridge
2. systemd-run gets a connection to the "foobar" container's
system bus, and invokes the "systemd-stdio-bridge" binary as
transient service inside a PAM session for the user "lennart"
3. The systemd-stdio-bridge then proxies our D-Bus traffic to
the user bus.
sd-bus (on host) → systemd-run (on host) → systemd-stdio-bridge (in container)
Complicated? Well, to some point yes, but otoh it's actually nice in
various other ways, primarily as it makes the -H and -M codepaths more
alike. In the -H case (i.e. connect to remote host via SSH) a very
similar three steps are used. The only difference is that instead of
"systemd-run" the "ssh" binary is used to invoke the stdio bridge in a
PAM session of some other system. Thus we get similar implementation and
isolation for similar operations.
Fixes: #14580
Let's a concept of "rate limiting" to event sources: if specific event
sources fire too often in some time interval temporarily take them
offline, and take them back online once the interval passed.
This is a simple scheme of avoiding starvation of event sources if some
event source fires too often.
This introduces the new conceptual states of "offline" and "online" for
event sources: an event source is "online" only when enabled *and* not
ratelimited, and offline in all other cases. An event source that is
online hence has its fds registered in the epoll, its signals in the
signalfd and so on.
So far we only reported major state transitions like failure to acquire
the message. Let's report the initial failure after a few timeouts in
a new event type.
The number of timeouts is hardcoded as 3, since Windows seems to be using
that. I don't think we need to make this configurable out of the box. A
reasonable default may be enough.
":" is prettier, but meson 0.56+ doesn't like it:
src/systemd/meson.build:73: DEPRECATION: ":" is not allowed in test name "cc-sd-bus.h:c", it has been replaced with "_"
src/systemd/meson.build:73: DEPRECATION: ":" is not allowed in test name "cc-sd-bus.h:c-ansi", it has been replaced with "_"
...
Fixes#17568.
With these patches applied, networkd is successfully able to get an
address from a DHCP server on an IPoIB interface.
1)
Makes networkd pass the actual interface type to the dhcp client,
instead of hardcoding it to Ethernet.
2)
Fixes some issues in handling the larger (20 Byte) IB MAC addresses in
the dhcp code.
3)
Add a new field to networkds Link struct, which holds the interface
broadcast address.
3.1)
Modify the DHCP code to also expect the broadcast address as parameter.
On an Ethernet-Interface the Broadcast address never changes and is always
all 6 bytes set to 0xFF.
On an IB one however it is not neccesarily always the same, thus
fetching the actual address from the interface is neccesary.
4)
Only the last 8 bytes of an IB MAC are stable, so when using an IB MAC to
generate a client ID, only pass those 8 bytes.
Currently, if an event source callback returns an error, we'll disable
the event source and continue. This adds a per-event source flag that if
turned on goes further: the event loop is also exited, propagating the
error code.
This is inspired by some patterns repeatedly seen in #15206.
The idea is that event sources that server the "primary" function of a
program are marked like this, so that if they fail the failure is
instantly propagated and terminates the program.
KEY_RESTART is widely used in Linux to indicate device reboot.
So lets handle it in the same fashion as KEY_POWER.
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
sd_seat_get_sessions() would return 0 in the 'n_uids' (now 'ret_n_uids') output
parameter when 'uid' (now 'ret_uids') was passed as NULL.
While at it, drop FOREACH_WORD() use.
Also use any whitespace as separator. In practice this shouldn't matter, since
logind always uses spaces, but it seems nicer to not specify this explicitly,
and the default is more flexible.
So far we kept all defines directly originating from the spec in
sd-bus-protocol.h, do this for this too.
The precise place doesn't matter much API-wise given that sd-bus.h includes
sd-bus-protocol.h, hence let's just clean this up.
This tries to address the "bind"/"unbind" uevent kernel API breakage, by
changing the semantics of device tags.
Previously, tags would be applied on uevents (and the database entries
they result in) only depending on the immediate context. This means that
if one uevent causes the tag to be set and the next to be unset, this
would immediately effect what apps would see and the database entries
would contain each time. This is problematic however, as tags are a
filtering concept, and if tags vanish then clients won't hence notice
when a device stops being relevant to them since not only the tags
disappear but immediately also the uevents for it are filtered including
the one necessary for the app to notice that the device lost its tag and
hence relevance.
With this change tags become "sticky". If a tag is applied is once
applied to a device it will stay in place forever, until the device is
removed. Tags can never be removed again. This means that an app
watching a specific set of devices by filtering for a tag is guaranteed
to not only see the events where the tag is set but also all follow-up
events where the tags might be removed again.
This change of behaviour is unfortunate, but is required due to the
kernel introducing new "bind" and "unbind" uevents that generally have
the effect that tags and properties disappear and apps hence don't
notice when a device looses relevance to it. "bind"/"unbind" events were
introduced in kernel 4.12, and are now used in more and more subsystems.
The introduction broke userspace widely, and this commit is an attempt
to provide a way for apps to deal with it.
While tags are now "sticky" a new automatic device property
CURRENT_TAGS is introduced (matching the existing TAGS property) that
always reflects the precise set of tags applied on the most recent
events. Thus, when subscribing to devices through tags, all devices that
ever had the tag put on them will be be seen, and by CURRENT_TAGS it may
be checked whether the device right at the moment matches the tag
requirements.
See: #7587#7018#8221
The commit 1070d271fa which was supposed
too fix this does not seem to take effect any more. We get again 34%
compilation success rate while scanning systemd itself. Moreover, the
installed header file breaks compilation of programs that include it:
"/usr/include/systemd/_sd-common.h", line 23: error #35: #error directive: "Do
not include _sd-common.h directly; it is a private header."
# error "Do not include _sd-common.h directly; it is a private header."
^
We frequently want to set a timer relative to the current time. Let's
add an explicit API for this. This not only saves us a few lines of code
everywhere and simplifies things, but also allows us to do correct
overflow checking.
SD_JOURNAL_FOREACH_DATA() and SD_JOURNAL_FOREACH_UNIQUE() would immediately
terminate when a field couldn't be accessed. This can happen for example when a
field is compressed with an unavailable compression format. But it's likely
that this is the wrong thing to do: the caller for example might want to
iterate over the fields but isn't interested in all of them. coredumpctl is
like this: it uses SD_JOURNAL_FOREACH_DATA() but only uses a subset of the
fields.
Add two new functions sd_journal_enumerate_good_data() and
sd_journal_enumerate_good_unique() that retry sd_journal_enumerate_data() and
sd_journal_enumerate_unique() if the return value is something that applies to
a single field: ENOBUS, E2BIG, EOPNOTSUPP.
Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1856037.
An alternative would be to make the macros themselves smarter instead of adding
new symbols, and do the looping internally in the macro. I don't like that
approach for two reasons. First, it would embed the logic in the macro, so
recompilation would be required if we decide to update the logic. With the
current version of the patch, recompilation is required to use the new symbols,
but after that, library upgrades are enough. So the current approach is safer
in case further updates are needed. Second, our headers use primitive C, and it
is hard to do the macros without using newer features.
Let's add a catalog entry explaining further details.
Most importantly though: talk to PID 1 directly, via the private D-Bus
socket, so that this actually works correctly during early boot, where
D-Bus is not around.
While investigating https://github.com/systemd/systemd/issues/16356, I
discovered that networkd stops the radv service before adding or updating
prefixes and then starts it again. This causes networkd to send an RA with
a router lifetime of zero, causing the routes to flap on systems receiving
the RA for a fraction of a second before radv is started again and proper
RAs are sent. That has the potential to cause issues with latency-sensitive
traffic like gaming or VoIP. This patch adds a boolean argument to the
sd_radv_stop() function to control this behavior. The zero lifetime RA is
still sent whenever radv is actually being stopped, but when it is being
restarted for a prefix update (from networkd-dhcp6.c), the final RA is no
longer sent to avoid the route flapping.
This is an attempt to clean up the POP3/SMTP/LPR/… DHCP lease server
data logic in networkd. This reduces code duplication and fixes a number
of bugs.
This removes any support for collecting POP3/SMPT/LPR servers acquired
via local DHCP client releases since noone uses that, and given how old
these protocols are I doubt this will change. It keeps support for
configuring them for the dhcp server however.
The differences between the DNS/NTP/SIP/POP3/SMTP/LPR configuration
logics are minimized.
This removes the relevant symbols from sd-network.h (which is an
internal API only at this point after all).
This is unfortunately not well test, given the old code for this had
barely any tests. But the new code should not perform worse at least,
and allow us to release, since it corrects some interfaces visible in
the .network configuration format.
Fixes: #15943
Yu Watanabe