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path: root/src/resolve/resolved-resolv-conf.c
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2016-11-10resolved: use macro for private resolve.confChristian Hesse
Use the macro from header file to have a single definition of the path.
2016-09-30resolved: don't query domain-limited DNS servers for other domains (#3621)Martin Pitt
DNS servers which have route-only domains should only be used for the specified domains. Routing queries about other domains there is a privacy violation, prone to fail (as that DNS server was not meant to be used for other domains), and puts unnecessary load onto that server. Introduce a new helper function dns_server_limited_domains() that checks if the DNS server should only be used for some selected domains, i. e. has some route-only domains without "~.". Use that when determining whether to query it in the scope, and when writing resolv.conf. Extend the test_route_only_dns() case to ensure that the DNS server limited to ~company does not appear in resolv.conf. Add test_route_only_dns_all_domains() to ensure that a server that also has ~. does appear in resolv.conf as global name server. These reproduce #3420. Add a new test_resolved_domain_restricted_dns() test case that verifies that domain-limited DNS servers are only being used for those domains. This reproduces #3421. Clarify what a "routing domain" is in the manpage. Fixes #3420 Fixes #3421
2016-06-21resolved: respond to local resolver requests on 127.0.0.53:53Lennart Poettering
In order to improve compatibility with local clients that speak DNS directly (and do not use NSS or our bus API) listen locally on 127.0.0.53:53 and process any queries made that way. Note that resolved does not implement a full DNS server on this port, but simply enough to allow normal, local clients to resolve RRs through resolved. Specifically it does not implement queries without the RD bit set (these are requests where recursive lookups are explicitly disabled), and neither queries with DNSSEC DO set in combination with DNSSEC CD (i.e. DNSSEC lookups with validation turned off). It also refuses zone transfers and obsolete RR types. All lookups done this way will be rejected with a clean error code, so that the client side can repeat the query with a reduced feature set. The code will set the DNSSEC AD flag however, depending on whether the data resolved has been validated (or comes from a local, trusted source). Lookups made via this mechanisms are propagated to LLMNR and mDNS as necessary, but this is only partially useful as DNS packets cannot carry IP scope data (i.e. the ifindex), and hence link-local addresses returned cannot be used properly (and given that LLMNR/mDNS are mostly about link-local communication this is quite a limitation). Also, given that DNS tends to use IDNA for non-ASCII names, while LLMNR/mDNS uses UTF-8 lookups cannot be mapped 1:1. In general this should improve compatibility with clients bypassing NSS but it is highly recommended for clients to instead use NSS or our native bus API. This patch also beefs up the DnsStream logic, as it reuses the code for local TCP listening. DnsStream now provides proper reference counting for its objects. In order to avoid feedback loops resolved will no silently ignore 127.0.0.53 specified as DNS server when reading configuration. resolved listens on 127.0.0.53:53 instead of 127.0.0.1:53 in order to leave the latter free for local, external DNS servers or forwarders. This also changes the "etc.conf" tmpfiles snippet to create a symlink from /etc/resolv.conf to /usr/lib/systemd/resolv.conf by default, thus making this stub the default mode of operation if /etc is not populated.
2016-06-21resolved: make sure that route-only domains are never added to /etc/resolv.confLennart Poettering
After all, /etc/resolv.conf doesn't know the concept of "route-only domains", hence the domains should really not appear there.
2016-06-06resolved: also rewrite private /etc/resolv.conf when configuration is ↵Lennart Poettering
changed via bus calls This also moves log message generation into manager_write_resolv_conf(), so that it is shorter to invoke the function, given that we have to invoke it at a couple of additional places now. Fixes: #3225
2016-06-06resolved: support IPv6 DNS servers on the local linkLennart Poettering
Make sure we can parse DNS server addresses that use the "zone id" syntax for local link addresses, i.e. "fe80::c256:27ff:febb:12f%wlp3s0", when reading /etc/resolv.conf. Also make sure we spit this out correctly again when writing /etc/resolv.conf and via the bus. Fixes: #3359
2016-06-03resolved: fix comments in resolve.conf for search domain overflows (#3422)Martin Pitt
Write comments about "too many search domains" and "Total length of all search domains is too long" just once. Also put it on a separate line, as resolv.conf(5) only specifies comments in a line by themselves. This is ugly to do if write_resolv_conf_search() gets called once for every search domain. So change it to receive the complete OrderedSet instead and do the iteration by itself. Add test cases to networkd-test.py. https://launchpad.net/bugs/1588229
2016-02-22tree-wide: make ++/-- usage consistent WRT spacingVito Caputo
Throughout the tree there's spurious use of spaces separating ++ and -- operators from their respective operands. Make ++ and -- operator consistent with the majority of existing uses; discard the spaces.
2016-02-10tree-wide: remove Emacs lines from all filesDaniel Mack
This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.
2016-01-28resolved: emit full path to file we failed to writeZbigniew Jędrzejewski-Szmek
Otherwise it's unclear if it's /etc/resolv.conf or some other file that is meant.
2016-01-11resolved: cache formatted server string in DnsServer structureLennart Poettering
This makes it easier to log information about a specific DnsServer object.
2015-11-27resolved: flush the global DNS cache if /etc/resolv.conf is touchedLennart Poettering
After all /etc/resolv.conf is usually done when the network configuration changes, which is a good reason to flush the global cache. See: #2038
2015-11-27resolved: don't clear the server list too eagerlyLennart Poettering
If /etc/resolv.conf is missing, this should not result in the server list to be cleared, after all the native data from resolved.conf shouldn't be flushed out then. Hence flush out the data only if /etc/resolv.conf exists, but we cannot read it for some reason.
2015-11-25resolved: split out calls to compile full list of dns servers and search domainsLennart Poettering
Let's split this out from the resolv.conf parser, so that this becomes generically useful.
2015-11-25resolved: unify DnsServer handling code between Link and ManagerLennart Poettering
This copies concepts we introduced for the DnsSearchDomain stuff, and reworks the operations on lists of dns servers to be reusable and generic for use both with the Link and the Manager object.
2015-11-25resolved: add a generic DnsSearchDomain conceptLennart Poettering
With this change, we add a new object to resolved, "DnsSearchDomain=" which wraps a search domain. This is then used to introduce a global search domain list, in addition to the existing per-link search domain list which is reword to make use of this new object too. This is preparation for implement proper unicast DNS search domain support.
2015-11-25resolved: rework dns server lifecycle logicLennart Poettering
Previously, there was a chance of memory corruption, because when switching to the next DNS server we didn't care whether they linked list of DNS servers was still valid. Clean up lifecycle of the dns server logic: - When a DnsServer object is still in the linked list of DnsServers for a link or the manager, indicate so with a "linked" boolean field, and never follow the linked list if that boolean is not set. - When picking a DnsServer to use for a link ot manager, always explicitly take a reference. This also rearranges some logic, to make the tracking of dns servers by link and globally more alike.
2015-11-25resolved: split out all code dealing with /etc/resolv.conf into its own .c fileLennart Poettering
No functional changes.