This fixes a bug introduced by ae45e1a383.
The set DnsAnswer::set_items contains the reference to the array in
DnsAnswer. So, the set must be reconstructed when we realloc() the
object.
Fixes#18132.
Previously, dns_answer_add() was O(n^2).
With this change dns_packet_extract() becomes ~15 times faster for some
extremal case.
Before:
```
$ time ./fuzz-dns-packet ~/downloads/clusterfuzz-testcase-minimized-fuzz-dns-packet-5631106733047808
/home/watanabe/downloads/clusterfuzz-testcase-minimized-fuzz-dns-packet-5631106733047808... ok
real 0m15.453s
user 0m15.430s
sys 0m0.007s
```
After:
```
$ time ./fuzz-dns-packet ~/downloads/clusterfuzz-testcase-minimized-fuzz-dns-packet-5631106733047808
/home/watanabe/downloads/clusterfuzz-testcase-minimized-fuzz-dns-packet-5631106733047808... ok
real 0m0.831s
user 0m0.824s
sys 0m0.006s
```
Hopefully fixes oss-fuzz#19227.
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=19227
Use symlink_atomic_label() instead of symlink_atomic() as the symlink
may need a different label than the parent directory.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Back in 5248e7e1f1 (July 2017) we moved over to
"_gateway", with the old name declared to be temporary measure. Since we're
doing a bunch of changes to resolved now, it seems to be a good moment to make
this simplification and not add support for the compat name in new code.
Either suppress the entry entirely, or not at all. But do not suppress
the "localhost" names we recognize, leaving the ones we do not in place.
On Fedora, where "localhost4.localdomain4" is among those listed in
/etc/hosts for 127.0.0.1 we'd thus otherwise drop the "localhost" but
keep the "localhost4.localdomain4" and then on reverse lookups only
return that, which is highly confusing.
Make them rather fail than go to the network.
Previously we'd filter them on LLMNR (explicitly) and MDNS (implicitly,
because it doesn't have .local suffix), but not on DNS.
In order to make _gateway truly reliable, let's not allow it to go to
DNS either, and keep it local.
This is particular relevant, as clients can now request lookups without
local RR synthesis, where we'd rather have NXDOMAIN returned for
_gateway than have it hit the network.
Apparently 30s is a bit too long for some cases, see #5552. But not
caching SERVFAIL at all also breaks stuff, see explanation in
201d99584e.
Let's try to find some middle ground, by lowering the cache timeout to
10s. This should be ample for the problem
201d99584e attackes, but not as long as
half a miute, as #5552 complains.
Fixes: #5552
DNSSEC validation takes the system clock into account to validate
signatures. This means if we had incorrect time and the time is then
changed to the correct one we should flush out everything and
re-validate taking the new time into account.
(This logic will also trigger after system suspend, which is not bad
either, given that quite possibly we are connected to a different
network, and thus would get different DNS data, without us noticing
otherwise via link beat).
Apparently, IF_UNICAST_IF does not influence the routing decisions done
during connect(). But SO_BINDTODEVICE/SO_BINDTOINDEX does, which however
brings a lot of other semantics with it, we are not so interested in
(i.e. it doesn't not allow packets from any other iface to us, even if
routing otherwise allows it).
Hence, let's bind to the ifindex immediately before the connect() and
unbind right after again, so that we get the semantics we want, but not
the ones we don't.
Fixes: #11935
Replaces: #12004
This reverts commit 34136e1503.
Having the "%H" host name specifier in a DNSSD service name template
triggers a failed assertion during name template instantiation as
specifier_dnssd_host_name expects DnssdService in its userdata
pointer but finds NULL instead.
This is useful for development where overwriting files out side
the configured prefix will affect the host as well as stateless
systems such as NixOS that don't let packages install to /etc but handle
configuration on their own.
Alternative to https://github.com/systemd/systemd/pull/17501
tested with:
$ mkdir inst build && cd build
$ meson \
-Dcreate-log-dirs=false \
-Dsysvrcnd-path=$(realpath ../inst)/etc/rc.d \
-Dsysvinit-path=$(realpath ../inst)/etc/init.d \
-Drootprefix=$(realpath ../inst) \
-Dinstall-sysconfdir=false \
--prefix=$(realpath ../inst) ..
$ ninja install
If we encounter an RR that has no matching signature, then we don't know
whether it was expanded from a wildcard or not. We need to accept that
and not make the NSEC test fail, just skip over the RR.