tree-wide: remove Emacs lines from all files This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.

resolved: rework what ResolveHostname() with family == AF_UNSPEC means Previously, if a hostanem is resolved with AF_UNSPEC specified, this would be used as indication to resolve both an AF_INET and an AF_INET6 address. With this change this logic is altered: an AF_INET address is only resolved if there's actually a routable IPv4 address on the specific interface, and similar an AF_INET6 address is only resolved if there's a routable IPv6 address. With this in place, it's ensured that the returned data is actually connectable by applications. This logic mimics glibc's resolver behaviour. Note that if the client asks explicitly for AF_INET or AF_INET6 it will get what it asked for. This also simplifies the logic how it is determined whether a specific lookup shall take place on a scope. Specifically, the checks with dns_scope_good_key() are now moved out of the transaction code and into the query code, so that we don't even create a transaction object on a specific scope if we cannot execute the resolution on it anyway.

resolved: teach resolved the difference between "routing" and "search" domains Following the changes to expose the "routing" and "search" domain concepts in networkd, actually make resolved use them. It will now use routing domains exclusively for making DNS routing decisions, and use search domains additionally for extending single-label names.

networkd: rework Domains= setting Previously, .network files only knew a vaguely defined "Domains=" concept, for which the documentation declared it was the "DNS domain" for the network connection, without specifying what that means. With this the Domains setting is reworked, so that there are now "routing" domains and "search" domains. The former are to be used by resolved to route DNS request to specific network interfaces, the latter is to be used for searching single-label hostnames with (in addition to being used for routing). Both settings are configured in the "Domains=" setting. Normal domain names listed in it are now considered search domains (for compatibility with existing setups), while those prefixed with "~" are considered routing domains only. To route all lookups to a specific interface the routing domain "." may be used, referring to the root domain. An alternative syntax for this is the "*", as was already implemented before using the "wildcard" domain concept. This commit adds proper parsers for this new logic, and exposes this via the sd-network API. This information is not used by resolved yet, this will be added in a later commit.

resolved: when checking whether a link is relevant, check kernel operstate This mimics what networkd is doing to detect a carrier.

resolved: rework DNSSECSupported property Not only report whether the server actually supports DNSSEC, but also first check whether DNSSEC is actually enabled for it in our local configuration. Also, export a per-link DNSSECSupported property in addition to the existing manager-wide property.

resolved: add bus API for configuring per-link DNS settings This is useful for alternative network management solutions (such as NetworkManager) to push DNS configuration data into resolved. The calls will fail should networkd already have taken possesion of a link, so that the bus API is only available if we don't get the data from networkd.

resolved: allocate DNS scope for links only if the interface is up For mDNS and LLMNR we already created the scopes only if the specific interfaces where actually up and suitable for Multicasting. Add a similar (but weaker) logic for unicast DNS as well.

resolved: when switching between DNSSEC modes, possibly flush caches If the networkd configuration changes during runtime, make sure to flush all caches when we switch from a less trusted to a more trusted mode.

resolved: cache formatted server string in DnsServer structure This makes it easier to log information about a specific DnsServer object.

resolved: introduce support for per-interface negative trust anchors

resolved,networkd: add a per-interface DNSSEC setting This adds a DNSSEC= setting to .network files, and makes resolved honour them.

resolved: log about per-interface setting parse errors

resolved: properly release all DnsServers that belong to a link

networkd,resolved: add a per-interface mdns configuration option

resolved,networkd: unify ResolveSupport enum networkd previously knew an enum "ResolveSupport" for configuring per-interface LLMNR support, resolved had a similar enum just called "Support", with the same value and similar pasers. Unify this, call the enum ResolveSupport, and port both daemons to it.

resolved: don't complain if networkd doesn't know an interface we care about

resolved: create dns scopes for mDNS Follow what LLMNR does, and create per-link DnsScope objects.

resolved: unify DnsServer handling code between Link and Manager 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.

resolved: add a generic DnsSearchDomain concept 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.

resolved: make sure order of dns servers is stable Previously, we'd keep adding new dns servers we discover to the end of our linked list of servers. When we encountered a pre-existing server, we'd just leave it where it was. In essence that meant that old servers ended up at the front, and new servers at the end, but not in an order that would reflect the configuration. With this change we ensure that every pre-existing server we want to add again we move to the back of the linked list, so that the order is stable and in sync with the requested configuration.

resolved: rework dns server lifecycle logic 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.

util-lib: split out allocation calls into alloc-util.[ch]

util-lib: split string parsing related calls from util.[ch] into parse-util.[ch]

util-lib: split our string related calls from util.[ch] into its own file string-util.[ch] There are more than enough calls doing string manipulations to deserve its own files, hence do something about it. This patch also sorts the #include blocks of all files that needed to be updated, according to the sorting suggestions from CODING_STYLE. Since pretty much every file needs our string manipulation functions this effectively means that most files have sorted #include blocks now. Also touches a few unrelated include files.

tree-wide: make use of the fact that strv_free() returns NULL Another Coccinelle patch.

resolved: rework synthesizing logic 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.

resolved: reference count the dns servers We want to reference the servers from their active transactions, so make sure they stay around as long as the transaction does.

sd-netlink: rename from sd-rtnl

resolved: fix crash when shutting down Reported by Cristian Rodríguez http://lists.freedesktop.org/archives/systemd-devel/2015-May/031626.html

treewide: no need to negate errno for log_*_errno() It corrrectly handles both positive and negative errno values.

treewide: auto-convert the simple cases to log_*_errno() 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().

hashmap: introduce hash_ops to make struct Hashmap smaller It is redundant to store 'hash' and 'compare' function pointers in struct Hashmap separately. The functions always comprise a pair. Store a single pointer to struct hash_ops instead. systemd keeps hundreds of hashmaps, so this saves a little bit of memory.

resolved: pull in domain names from sd-network

resolved: enable LLMNR THis was accidentally broken, as we truned off LLMNR far to frequently, where we only wanted to turn off LLMNr on IPV6 on kernels lacking support for it.

sd-network: /_get_link_/_link_get_/ The link is the 'object', so make this in line with our usual naming convention. Suggested by Kay and Lennart.

resolved: skip IPv6 LLMNR if IPv6 is not available

sd-network: rename the per-ifindex calls to sd_network_get_link_xxx() This way we can introduce system-wide versions of these calls that are called the same way, but without the "link" in the name.

resolved: don't consider tentative addresses relevant

resolved: fix a message typo

resolved: read the per-interface LLMNR setting from networkd and act on it

resolved: flush cache each time we change to a different DNS server

resolved: read the system /etc/resolv.conf unless we wrote it ourselves This way we integrate nicely with foreign network management stacks, such as NM.

resolved: beef up DNS server configuration logic We now maintain two lists of DNS servers: system servers and fallback servers. system servers are used in combination with any per-link servers. fallback servers are only used if there are no system servers or per-link servers configured. The system server list is supposed to be populated from a foreign tool's /etc/resolv.conf (not implemented yet). Also adds a configuration switch for LLMNR, that allows configuring whether LLMNR shall be used simply for resolving or also for responding.

resolved: implement LLMNR uniqueness verification

resolved: properly set TTL in SOA records

resolved: don't do llmnr on interfaces lacking multicasting

resolved: follow more closely the recommend timeouts and TTLs from the LLMNR spec

resolve: add llmnr responder side for UDP and TCP Name defending is still missing.

sd-network: expose DNS/NTP servers as strings This avoids having to distinguish between IPv4 and IPv6, allowing us to keep their internal orderings. The consumers now has to turn the strings into addresses.

resolved: don't read DHCP leases networkd will expose both statically configured DNS servers and servers receieved over DHCP in sd_network_get_dns(), so no need to keep the distinction in resolved.

networkd: merge DNS and NTP entries when exporting In the state files, do not distinguish where the various entries came from (static or DHCP), but include them all in the same list.

change type for address family to "int" Let's settle on a single type for all address family values, even if UNIX is very inconsitent on the precise type otherwise. Given that socket() is the primary entrypoint for the sockets API, and that uses "int", and "int" is relatively simple and generic, we settle on "int" for this.

resolved: add LLMNR support for looking up names

resolved: don't trip up when an rtlink message does not include the MTU

sd-network: remove redundant array size parameter from functions that return arrays As long as the number of array entries is relatively small it's nicer to simply return the number of entries directly, instead of using a size_t* return parameter for it.

resolved: properly handle MTU logic

resolved: do not free() sd_dhcp_lease_get_dns() results

resolved: add a DNS client stub resolver Let's turn resolved into a something truly useful: a fully asynchronous DNS stub resolver that subscribes to network changes. (More to come: caching, LLMNR, mDNS/DNS-SD, DNSSEC, IDN, NSS module)