We quite obviously check whether event->dev_db is nonnull, and
right after that call a function which asserts the same. Move
the call under the same if.
https://bugzilla.redhat.com/show_bug.cgi?id=1283971
Fixes:
$ ./autogen.sh
$ ./configure ... --disable-timesyncd
$ make distcheck
...
make[1]: *** No rule to make target 'src/timesync/timesyncd-gperf.gperf', needed by 'src/timesync/timesyncd-gperf.c'. Stop.
This adds a new SD_RESOLVED_AUTHENTICATED flag for responses we return
on the bus. When set, then the data has been authenticated. For now this
mostly reflects the DNSSEC AD bit, if DNSSEC=trust is set. As soon as
the client-side validation is complete it will be hooked up to this flag
too.
We also set this bit whenver we generated the data ourselves, for
example, because it originates in our local LLMNR zone, or from the
built-in trust anchor database.
The "systemd-resolve-host" tool has been updated to show the flag state
for the data it shows.
When an RR type is not set in an NSEC, then the CNAME/DNAME types might
still be, hence check them too.
Otherwise we might end up refusing resolving of CNAME'd RRs if we cached
an NSEC before.
The setting controls which kind of DNSSEC validation is done: none at
all, trusting the AD bit, or client-side validation.
For now, no validation is implemented, hence the setting doesn't do much
yet, except of toggling the CD bit in the generated messages if full
client-side validation is requested.
When doing DNSSEC lookups we need to know one or more DS or DNSKEY RRs
as trust anchors to validate lookups. With this change we add a
compiled-in trust anchor database, serving the root DS key as of today,
retrieved from:
https://data.iana.org/root-anchors/root-anchors.xml
The interface is kept generic, so that additional DS or DNSKEY RRs may
be served via the same interface, for example by provisioning them
locally in external files to support "islands" of security.
The trust anchor database becomes the fourth source of RRs we maintain,
besides, the network, the local cache, and the local zone.
Previously, we'd never do any single-label or root domain lookups via
DNS, thus leaving single-label lookups to LLMNR and the search path
logic in order that single-label names don't leak too easily onto the
internet. With this change we open things up a bit, and only prohibit
A/AAAA lookups of single-label/root domains, but allow all other
lookups. This should provide similar protection, but allow us to resolve
DNSKEY+DS RRs for the top-level and root domains.
(This also simplifies handling of the search domain detection, and gets
rid of dns_scope_has_search_domains() in favour of
dns_scope_get_search_domains()).
Sometimes when looking up entries in hashmaps indexed by a
DnsResourceKey it is helpful not having to allocate a full
DnsResourceKey dynamically just to use it as search key. Instead,
optionally allow allocation of a DnsResourceKey on the stack. Resource
keys allocated like that of course are subject to other lifetime cycles
than the usual Resource keys, hence initialize the reference counter to
to (unsigned) -1.
While we are at it, remove the prototype for
dns_resource_key_new_dname() which was never implemented.
Borked since
commit 3ee897d6c2
Author: Lennart Poettering <lennart@poettering.net>
Date: Wed Sep 23 01:00:04 2015 +0200
tree-wide: port more code to use send_one_fd() and receive_one_fd()
because here our fd is not connected and we need to specify
the address.
If we have a precisely matching NSEC RR for a name, we can use its type
bit field to synthesize NODATA cache lookup results for all types not
mentioned in there.
This is useful for mDNS where NSEC RRs are used to indicate missing RRs
for a specific type, but is beneficial in other cases too.
To test this, consider these two lines:
systemd-resolve-host -t NSEC nasa.gov
systemd-resolve-host -t SRV nasa.gov
The second line will not result in traffic as the first line already
cached the NSEC field.
This adds most basic operation for doing DNSSEC validation on the
client side. However, it does not actually add the verification logic to
the resolver. Specifically, this patch only includes:
- Verifying DNSKEY RRs against a DS RRs
- Verifying RRSets against a combination of RRSIG and DNSKEY RRs
- Matching up RRSIG RRs and DNSKEY RRs
- Matching up RR keys and RRSIG RRs
- Calculating the DNSSEC key tag from a DNSKEY RR
All currently used DNSSEC combinations of SHA and RSA are implemented. Support
for MD5 hashing and DSA or EC cyphers are not. MD5 and DSA are probably
obsolete, and shouldn't be added. EC should probably be added
eventually, if it actually is deployed on the Internet.
