This function doesn't "connect" to Varlink (i.e. it isn't a client) but
it binds a Varlink socket (i.e. it is server), hence let's remove the
verb "connect" from its name. let's copy how machined/resolved name the
counterpart for this function: manager_varlink_init()
Let's synthesize DNS RRs for leases handed out by our DHCP server. This
way local VMs can have resolvable hostnames locally.
This does not implement reverse look ups for now. We can add this
later in similar fashion.
This basically implements nss-myhostname, but natively in
systemd-resolved, so that the logic becomes available also for clients
using the local DNS stub for resolution or the D-Bus or Varlink APIs.
This introduces /run/systemd/resolve.hook/ as a new directory that local
(privileged) programs can bind a Varlink socket into. If they do they'll
get a method call for each attempted resolved lookup, which they can
then either process themselves (and generate new records for, or return
errors to block stuff) or let pass so that the regular resolution is
done.
Usecase for this is primarily two things:
1. in machined we can add local resolution of machine names to their IP
addresses, similar in fashion to nss-mymachines, but working also if
the non-NSS interfaces to name resolution are used, i.e. the local
DNS responder. In fact, I think we should eventually remove
nss-mymachines from our tree, as soon as this code in resolved is
setlled.
2. in networkd we can add local resolution of names specified in DHCP
leases we hand out.
But beyond that there should be many other uses, for example people
could write "dns firewalls" with this if they like where they
dynamically block certain names from resolution.
Fixes: #8518
Reverts systemd/systemd#38680
After taking a closer look I'm not convinced by the approach, see below.
First of all, all other SD_PATH_SEARCH_* are either somewhat generic,
i.e. encode the common prefix for configurations, binaries, etc., or are
subdirectories under systemd/ hence in our own "domain". The
tmpfiles/sysctl/binfmt we don't prefix with "systemd" precisely because
the concept is generic and there're actually other impls of them. A
specific SD_PATH_SEARCH_SYSCTL doesn't fit into our existing scheme.
Instead something along the lines of "SEARCH_SYSTEM_CONFIGURATION" shall
be introduced, and consumers will just suffix
sysctl.d/tmpfiles.d/binfmt.d for the final result.
And secondly, I don't grok why systemd-sysctl now unnecessarily calls
into sd-path to obtain the fixed search path. None of our other tools do
that.
-----------
An alternate approach, SD_PATH_SYSTEM_SEARCH_CONFIGURATION, which does
exactly above, will be introduced instead. It provides a universal
interface for querying any system config with our idiomatic
/etc/:/run/:/usr/local/lib/:/usr/lib/ hierarchy.
We do this in a separate service (rather than inside of
systemd-tpm2-setup), since we want failures of this measurement to
result in an instant reboot, like for most our measurements.
Failures to initialize nvpcrs, or allocate an SRK are somewhat OK (and
more likely), as long as this separator communicates clearly where they
have to have taken place, if they worked.
This locks down NvPCR initilization a bit more: we'll measure each
initialization of an NvPCR into PCR 9, thus chaining the NvPCRs to the
PCR set. After all NvPCRs are initialized we measure a barrier into PCR
9 as well.
This ensures that later additions of NvPCRs are clearly recognizable and
distuingishable from those done at boot.
Its value depends on how strerror_r() implemented, and the
implementations of the function in glibc and musl are actually
different. Let's drop the checks.
musl provides XSI compliant strerror_r(), and it is slightly different
from the one by glibc.
Let's introduce a tiny wrapper to convert XSI strerror_r() to GNU one.
The wrapper also patches musl's spurious catchall error message.
Defer and exit event sources are marked pending once when they are added
and never again afterwards. This means their pending_iteration is never
incremented after they are initially added, which breaks fairness among
event sources with equal priority which depend on the pending_iteration
variable getting updated in source_set_pending(). To fix this, let's assign
iterations for defer and exit sources in source_dispatch() instead so that
those get their pending_iteration updated as well.
Sometimes it's hard to assign responsibility to a specific event source
for exiting when there's no more work to be done. So let's add exit-on-idle
support where we exit when there are no more event sources.
This enables running something like
"mkosi box -- run0 --empower --same-root-dir -E PATH" to get an
empowered session as the current user within the "mkosi box" environment.
As documented in sd_event_add_memory_pressure(), we can only add
the memory pressure fd to epoll once we've written the watch string,
so make sure we don't register the memory pressure in
event_source_online() until we've written the watch string.
More post event sources might get added during dispatching, we want
to make sure those become pending as well if we're dispatching a non-post
event source.
The kernel converts a bunch of errors to ESTALE in the open_by_handle_at()
codepath so we treat it as missing privs but it could be absolutely
anything really.
Currently the only supported integrity algorithm using HMAC is
`hmac-sha256`. Add `hmac-sha512` to the list of supported algorithms as
well.
Also add the `PHMAC` integrity algorithm to the list of supported
algorithms. The `PHMAC` algorithm is like the regular HMAC algorithm,
but it takes a wrapped key as input. A key for the `PHMAC` algorithm is
an opaque key blob, who's physical size has nothing to do with the
cryptographic size. Such a wrapped key can for example be a HSM
protected key. Currently PHMAC is only available for the s390x
architecture (Linux on IBM Z).
Support for PHMAC has just been added to the cryptsetup project via MR
https://gitlab.com/cryptsetup/cryptsetup/-/merge_requests/693 by commit
296eb39c60
To allow automatic opening of integrity protected volumes that use PHMAC
via `/etc/integritytab`, this change in systemd's integritysetup tool is
needed as well.
This adds a new `Hostname=` option to the [DHCPServerStaticLease]
section in .network files, allowing an administrator to assign a
specific hostname to a client receiving a static lease.
We automatically select the correct DHCP option to use based on the
format of the provided string:
- Single DNS labels are sent as Option 12.
- Names with multiple DNS labels are sent as Option 81 in wire format.
Fixes: #39634
