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path: root/src/resolve/resolved-dns-stream.c
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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.
2016-02-10tree-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.
2016-01-11resolved: set a description on all our event sourcesLennart Poettering
2015-12-26resolved: don't set TCP_NODELAY twice for TCP socketsLennart Poettering
We previously set it once in the scope code and once in the stream code. Remove it from the latter, as all other socket options are set in the former.
2015-10-27util-lib: split out allocation calls into alloc-util.[ch]Lennart Poettering
2015-10-27io-util.h: move iovec stuff from macro.h to io-util.hLennart Poettering
2015-10-25util-lib: split out fd-related operations into fd-util.[ch]Lennart Poettering
There are more than enough to deserve their own .c file, hence move them over.
2015-06-10util: introduce CMSG_FOREACH() macro and make use of it everywhereLennart Poettering
It's only marginally shorter then the usual for() loop, but certainly more readable.
2014-11-28treewide: use log_*_errno whenever %m is in the format stringMichal Schmidt
If the format string contains %m, clearly errno must have a meaningful value, so we might as well use log_*_errno to have ERRNO= logged. Using: find . -name '*.[ch]' | xargs sed -r -i -e \ 's/log_(debug|info|notice|warning|error|emergency)\((".*%m.*")/log_\1_errno(errno, \2/' Plus some whitespace, linewrap, and indent adjustments.
2014-10-22resolved: simplify detection of packets from the loopback deviceLennart Poettering
We can simplify our code quite a bit if we explicitly check for the ifindex being 1 on Linux as a loopback check. Apparently, this is hardcoded on Linux on the kernel, and effectively exported to userspace via rtnl and such, hence we should be able to rely on it.
2014-08-22shared: add MAXSIZE() and use it in resolvedDavid Herrmann
The MAXSIZE() macro takes two types and returns the size of the larger one. It is much simpler to use than MAX(sizeof(A), sizeof(B)) and also avoids any compiler-extensions, unlike CONST_MAX() and MAX() (which are needed to avoid evaluating arguments more than once). This was suggested by Daniele Nicolodi <daniele@grinta.net>. Also make resolved use this macro instead of CONST_MAX(). This enhances readability quite a bit.
2014-08-15resolve: fix compilation on LLVM+clangDavid Herrmann
LLVM+clang does not allow statement-expressions inside of type-declarations (file-scope). Use CONST_MAX() to avoid this.
2014-08-01resolved: IPV6_UNICAST_IF may fail if we already are bound to a device, like ↵Lennart Poettering
we are for link-local addresses
2014-08-01resolved: use CLOCK_BOOTTIME instead of CLOCK_MONOTONIC when aging caches ↵Lennart Poettering
and timeing out transactions That way the cache doens't get confused when the system is suspended.
2014-07-29resolved: when resolving an address PTR record via llmnr, make a tcp ↵Lennart Poettering
connection by default
2014-07-29resolve: add llmnr responder side for UDP and TCPLennart Poettering
Name defending is still missing.