summaryrefslogtreecommitdiff
path: root/src/resolve/resolved-bus.c
AgeCommit message (Collapse)Author
2016-01-11resolved: don't attempt to send queries for DNSSEC RR types to servers not ↵Lennart Poettering
supporting them If we already degraded the feature level below DO don't bother with sending requests for DS, DNSKEY, RRSIG, NSEC, NSEC3 or NSEC3PARAM RRs. After all, we cannot do DNSSEC validation then anyway, and we better not press a legacy server like this with such modern concepts. This also has the benefit that when we try to validate a response we received using DNSSEC, and we detect a limited server support level while doing so, all further auxiliary DNSSEC queries will fail right-away.
2016-01-11resolved: when we get a TCP connection failure, try againLennart Poettering
Previously, when we couldn't connect to a DNS server via TCP we'd abort the whole transaction using a "connection-failure" state. This change removes that, and counts failed connections as "lost packet" events, so that we switch back to the UDP protocol again.
2016-01-11resolved: set a description on all our event sourcesLennart Poettering
2016-01-07resolved: query_process_cname - make fully recursiveTom Gundersen
This ensures we properly resolve the CNAME chain as far as we can, rather than only CNAME chains of length one.
2016-01-04resolved: explicitly handle case when the trust anchor is emptyLennart Poettering
Since we honour RFC5011 revoked keys it might happen we end up with an empty trust anchor, or one where there's no entry for the root left. With this patch the logic is changed what to do in this case. Before this patch we'd end up requesting the root DS, which returns with NODATA but a signed NSEC we cannot verify, since the trust anchor is empty after all. Thus we'd return a DNSSEC result of "missing-key", as we lack a verified version of the key. With this patch in place, look-ups for the root DS are explicitly recognized, and not passed on to the DNS servers. Instead, if downgrade-ok mode is on an unsigned NODATA response is synthesized, so that the validator code continues under the assumption the root zone was unsigned. If downgrade-ok mode is off a new transaction failure is generated, that makes this case recognizable.
2016-01-04resolved: introduce a proper bus error for DNSSEC validation errorsLennart Poettering
2015-12-29resolved: properly handle SRV RRs with the DNS root as hostnameLennart Poettering
2015-12-26resolved: generate an explicit transaction error when we cannot reach server ↵Lennart Poettering
via TCP Previously, if we couldn't reach a server via UDP we'd generate an MAX_ATTEMPTS transaction result, but if we couldn't reach it via TCP we'd generate a RESOURCES transaction result. While it is OK to generate two different errors I think, "RESOURCES" is certainly a misnomer. Introduce a new transaction result "CONNECTION_FAILURE" instead.
2015-12-26resolved: gather statistics about resolved namesLennart Poettering
This collects statistical data about transactions, dnssec verifications and the cache, and exposes it over the bus. The systemd-resolve-host tool learns new options to query these statistics and reset them.
2015-12-18resolved: propagate the DNSSEC result from the transaction to the query and ↵Lennart Poettering
the the bus client It's useful to generate useful errors, so let's do that.
2015-12-18resolved: rename DNS_TRANSACTION_FAILURE → DNS_TRANSACTION_RCODE_FAILURELennart Poettering
We have many types of failure for a transaction, and DNS_TRANSACTION_FAILURE was just one specific one of them, if the server responded with a non-zero RCODE. Hence let's rename this, to indicate which kind of failure this actually refers to.
2015-12-11resolved: generalize DNS RR type validity checksLennart Poettering
Check the validity of RR types as we parse or receive data from IPC clients, and use the same code for all of them.
2015-12-10resolved: chase DNSKEY/DS RRs when doing look-ups with DNSSEC enabledLennart Poettering
This adds initial support for validating RRSIG/DNSKEY/DS chains when doing lookups. Proof-of-non-existance, or proof-of-unsigned-zones is not implemented yet. With this change DnsTransaction objects will generate additional DnsTransaction objects when looking for DNSKEY or DS RRs to validate an RRSIG on a response. DnsTransaction objects are thus created for three reasons now: 1) Because a user asked for something to be resolved, i.e. requested by a DnsQuery/DnsQueryCandidate object. 2) As result of LLMNR RR probing, requested by a DnsZoneItem. 3) Because another DnsTransaction requires the requested RRs for validation of its own response. DnsTransactions are shared between all these users, and are GC automatically as soon as all of these users don't need a specific transaction anymore. To unify the handling of these three reasons for existance for a DnsTransaction, a new common naming is introduced: each DnsTransaction now tracks its "owners" via a Set* object named "notify_xyz", containing all owners to notify on completion. A new DnsTransaction state is introduced called "VALIDATING" that is entered after a response has been receieved which needs to be validated, as long as we are still waiting for the DNSKEY/DS RRs from other DnsTransactions. This patch will request the DNSKEY/DS RRs bottom-up, and then validate them top-down. Caching of RRs is now only done after verification, so that the cache is not poisoned with known invalid data. The "DnsAnswer" object gained a substantial number of new calls, since we need to add/remove RRs to it dynamically now.
2015-12-03resolved: add a concept of "authenticated" responsesLennart Poettering
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.
2015-12-02resolved: port ResolveRecord() bus call implementation to ↵Lennart Poettering
dns_resource_record_to_wire_format() Now that we have dns_resource_record_to_wire_format() we can generate the RR serialization we return to bus clients in ResolveRecord() with it. We pass the RR data along in the original form, not the DNSSEC canonical form, since that would mean we'd lose RR name casing, which is however important to keep for DNS-SD services and similar.
2015-11-27tree-wide: expose "p"-suffix unref calls in public APIs to make gcc cleanup easyLennart Poettering
GLIB has recently started to officially support the gcc cleanup attribute in its public API, hence let's do the same for our APIs. With this patch we'll define an xyz_unrefp() call for each public xyz_unref() call, to make it easy to use inside a __attribute__((cleanup())) expression. Then, all code is ported over to make use of this. The new calls are also documented in the man pages, with examples how to use them (well, I only added docs where the _unref() call itself already had docs, and the examples, only cover sd_bus_unrefp() and sd_event_unrefp()). This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we tend to call our destructors these days. Note that this defines no public macro that wraps gcc's attribute and makes it easier to use. While I think it's our duty in the library to make our stuff easy to use, I figure it's not our duty to make gcc's own features easy to use on its own. Most likely, client code which wants to make use of this should define its own: #define _cleanup_(function) __attribute__((cleanup(function))) Or similar, to make the gcc feature easier to use. Making this logic public has the benefit that we can remove three header files whose only purpose was to define these functions internally. See #2008.
2015-11-27resolved: fix buildLennart Poettering
2015-11-26Merge pull request #2031 from poettering/resolved-search-domainsTom Gundersen
resolved. Fully implement search domains for single-label names
2015-11-26resolved: bus - follow CNAME chains when resolving addressesTom Gundersen
It may be unexpected to find a CNAME record when doing a reverse lookup, as we expect to find a PTR record directly. However, it is explicitly supported according to <https://tools.ietf.org/html/rfc2181#section-10.2>, and there seems to be no benefit to not supporting it.
2015-11-25dns-domain: change dns_srv_type_is_valid() return value to boolLennart Poettering
For similar reasons as dns_name_is_root() got changed in the previous commit.
2015-11-25resolved: fully support DNS search domainsLennart Poettering
This adds support for searching single-label hostnames in a set of configured search domains. A new object DnsQueryCandidate is added that links queries to scopes. It keeps track of the search domain last used for a query on a specific link. Whenever a host name was unsuccessfuly resolved on a scope all its transactions are flushed out and replaced by a new set, with the next search domain appended. This also adds a new flag SD_RESOLVED_NO_SEARCH to disable search domain behaviour. The "systemd-resolve-host" tool is updated to make this configurable via --search=. Fixes #1697
2015-11-25resolved: expose some properties on the busLennart Poettering
For now, let's just expose the LLMNR hostname currently in use; a combined list of all dns servers with their interface indexes; a combined list of all search domains with their interface indexes.
2015-11-25resolved: don't claim DnsQuestion have to have the same namesLennart Poettering
Wen DnsQuestion objects are used for DnsQuery objects all contained keys have to share the same name, but otherwise they generally don't have to, and this can actually happen in real-life because DnsPacket objects for mDNS use DnsQuestion for the question section. Hence, rename: dns_question_is_valid() to dns_question_is_valid_for_query(), since the name uniqueness check it does is only relevant when used for a query. Similar, rename dns_question_name() to dns_question_first_name(), to be more accurate, as this difference matters if we keys don#t have to share the same name.
2015-11-24resolved: remove unused variableThomas Hindoe Paaboel Andersen
2015-11-23resolved: add ResolveService() bus call for resolving SRV and DNS-SD servicesLennart Poettering
This also adds client-side support for this to systemd-resolve-host. Note that the ResolveService() API can deal both with DNS-SD service (consisting of service name, type and domain), as well as classic SRV services (consisting just of a type and a domain), all exposed in the same call. This patch also reworks CNAME handling in order to reuse it between hostname, RR and service lookups. In contrast to Avahi and Bonjour, this new API will actually reolve the A/AAAA RRs the SRV RRs point to in one go (unless this is explicitly disabled). This normally comes for free, as these RRs are sent along the SRV responses anyway, hence let's make use of that. This makes the API considerably easier to use, as a single ResolveService() invocation will return all necessary data to pick a server and connect() to it. Note that this only implements the DNS-SD resolving step, it does not implement DNS-SD browsing, as that makes sense primarily on mDNS, due to its continuous nature.
2015-10-27util-lib: split out allocation calls into alloc-util.[ch]Lennart Poettering
2015-09-16resolved: cache - handle CNAME redirectionTom Gundersen
CNAME records are special in the way they are treated by DNS servers, and our cache should mimic that behavior: In case a domain name has an alias, its CNAME record is returned in place of any other. Our cache was not doing this despite caching the CNAME records, this entailed needless lookups to re-resolve the CNAME.
2015-09-16resolved: rr - introduce dns_resource_key_new_redirect()Tom Gundersen
Takes a key and CNAME RR and returns the canonical RR of the right type. Make use of this in dns_question_redirect().
2015-08-24resolved: remove duplicate handling of "no servers" query resultLennart Poettering
So far we handled immediate "no server" query results differently from "no server" results we ran into during operation: the former would cause the dns_query_go() call to fail with ESRCH, the later would result in the query completion callback to be called. Remove the duplicate codepaths, by always going through the completion callback. This allows us to remove quite a number of lines for handling the ESRCH. This commit should not alter behaviour at all.
2015-08-21resolved: when passing RRs across the bus, make sure not to use name compressionLennart Poettering
We explicitly need to turn off name compression when marshalling or demarshalling RRs for bus transfer, since they otherwise refer to packet offsets that reference packets that are not transmitted themselves.
2015-08-21resolved: rework synthesizing logicLennart Poettering
With this change we'll now also generate synthesized RRs for the local LLMNR hostname (first label of system hostname), the local mDNS hostname (first label of system hostname suffixed with .local), the "gateway" hostname and all the reverse PTRs. This hence takes over part of what nss-myhostname already implemented. Local hostnames resolve to the set of local IP addresses. Since the addresses are possibly on different interfaces it is necessary to change the internal DnsAnswer object to track per-RR interface indexes, and to change the bus API to always return the interface per-address rather than per-reply. This change also patches the existing clients for resolved accordingly (nss-resolve + systemd-resolve-host). This also changes the routing logic for queries slightly: we now ensure that the local hostname is never resolved via LLMNR, thus making it trustable on the local system.
2015-06-10resolve: move dns routines into sharedNick Owens
2015-04-29tree-wide: get rid of a few more explicit bus parametersLennart Poettering
2015-04-29sd-bus: drop bus parameter from message callback prototypeLennart Poettering
This should simplify the prototype a bit. The bus parameter is redundant in most cases, and in the few where it matters it can be derived from the message via sd_bus_message_get_bus().
2015-02-23resolved: use == for comparing unsigned against zeroZbigniew Jędrzejewski-Szmek
2015-02-03util: rework strappenda(), and rename it strjoina()Lennart Poettering
After all it is now much more like strjoin() than strappend(). At the same time, add support for NULL sentinels, even if they are normally not necessary.
2014-12-10sd-bus: move common errors src/shared/bus-errors.h → ↵Lennart Poettering
src/libsystemd/sd-bus/bus-common-errors.h Stuff in src/shared/ should not use stuff from src/libsystemd/ really.
2014-11-28treewide: yet more log_*_errno + return simplificationsMichal Schmidt
Using: find . -name '*.[ch]' | while read f; do perl -i.mmm -e \ 'local $/; local $_=<>; s/(if\s*\([^\n]+\))\s*{\n(\s*)(log_[a-z_]*_errno\(\s*([->a-zA-Z_]+)\s*,[^;]+);\s*return\s+\g4;\s+}/\1\n\2return \3;/msg; print;' $f done And a couple of manual whitespace fixups.
2014-11-28treewide: no need to negate errno for log_*_errno()Michal Schmidt
It corrrectly handles both positive and negative errno values.
2014-11-28treewide: auto-convert the simple cases to log_*_errno()Michal Schmidt
As a followup to 086891e5c1 "log: add an "error" parameter to all low-level logging calls and intrdouce log_error_errno() as log calls that take error numbers", use sed to convert the simple cases to use the new macros: find . -name '*.[ch]' | xargs sed -r -i -e \ 's/log_(debug|info|notice|warning|error|emergency)\("(.*)%s"(.*), strerror\(-([a-zA-Z_]+)\)\);/log_\1_errno(-\4, "\2%m"\3);/' Multi-line log_*() invocations are not covered. And we also should add log_unit_*_errno().
2014-08-14resolved: allow passing on which protocol, family and interface to look ↵Lennart Poettering
something up Also, return on which protocol/family/interface we found something.
2014-08-11resolved: verify all RRs when we come back from suspendLennart Poettering
2014-08-11resolved: destroy outstanding queries if the clients that initiated them dieLennart Poettering
2014-08-11resolved: properly pass aborted transaction result back to clientsLennart Poettering
2014-08-03resolved: remove unused variablesThomas Hindoe Paaboel Andersen
2014-08-01resolved: rename resolved.h to resolved-manager.hLennart Poettering
After all it pretty much exlcusively containers definitions about the "Manager" object, hence let's call this the most obvious way.
2014-07-31resolved: accept UTF-8 hostnames from bus clientsLennart Poettering
2014-07-31resolved: implement LLMNR uniqueness verificationLennart Poettering
2014-07-30resolved: add API for resolving specific RRsLennart Poettering
2014-07-30resolved: properly pass empty answers back to bus clientsLennart Poettering