Move the logic that sends goodbye messages, removes a registered DNS-SD
service's RRs from all mDNS zones and frees the service out of
bus_dnssd_method_unregister() into a new helper. While at it, add the
nowadays customary parameter comments and ", ignoring" log message
suffix to the moved code. No functional change.
This is preparation for unregistering services when the D-Bus client
that registered them disconnects: that path needs the full teardown as
well, not just dnssd_registered_service_free(), which would leave the
service's RRs published in the per-link mDNS zones.
The new polkit will return a new detail regarding a successful
authentication: the actual result type, which we can use to
see whether the user authenticated as admin. This can be used
to grant additional privileges.
Prepare for upcoming mDNS browse services.
Distinguish between registered and discovered services to avoid confusion.
Co-authored-by: Vishwanath Chandapur <vishwanath.chandapur@philips.com>
"name" is a bit confusing since this field is *not* the DNS-SD service
identifier, bust just some string derived from the .dnssd filename that
is used as handle for the service. Let's hence give it a better name:
"id".
While we are at it, switch from basename() to path_extract_filename().
This simplifies bus_verify_polkit_async() and related calls quite a bit:
1. This removes any support for authentication-by-Linux-capability. This
is ultimately a kdbus leftover: with classic AF_UNIX transports we
cannot authenticate by capabilities securely (because we cannot
acquire it from the peer without races), hence we never actually did.
Since the necessary kernel work didn't materialize in the last 10y,
and is unlikely to be added, let's just kill this context. We cannot
quite remove the caps stuff from sd-bus for API compat, but for our
polkit logic let's kill it.
2. The "good_uid" and "interactive" params are only necessary in very
few cases, hence let's move them to a new call
bus_verify_polkit_async_full() and make bus_verify_polkit_async() a
wrapper around it without those two parameters.
This also fixes a bunch of wrong uses of the "interactive" bool. The
bool makes no sense today as the ALLOW_INTERACTIVE_AUTHORIZATION field
in the D-Bus message header replaces it fully. We only need it to
implement method calls we introduced prior to that header field becoming
available in D-Bus. And it should only be used on such old method calls,
and otherwise always be set to false.
This does not change behaviour in any way. Just simplifies stuff.
Fixes: #21586
This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
This macro will read a pointer of any type, return it, and set the
pointer to NULL. This is useful as an explicit concept of passing
ownership of a memory area between pointers.
This takes inspiration from Rust:
https://doc.rust-lang.org/std/option/enum.Option.html#method.take
and was suggested by Alan Jenkins (@sourcejedi).
It drops ~160 lines of code from our codebase, which makes me like it.
Also, I think it clarifies passing of ownership, and thus helps
readability a bit (at least for the initiated who know the new macro)
Stefan Agner
Luca Boccassi
Vishal Chillara SrinivasandVishwanath Chandapur
Daan De Meyer
Yu Watanabe
Lennart Poettering
Ronan Pigott
Luca Boccassi
David Tardon
Zbigniew Jędrzejewski-Szmek
Dmitry Rozhkov