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.

util: introduce fputs_with_space() and make use of it at various places The call combines outputing a string with prefixing it with a space, optionally. This is useful to shorten the logic for outputing lists of strings, that are space separated.

networkd: optinally use DHCP lease domain info for routing only This changes the UseDomains= setting of .network files to take an optional third value "route", in addition to the boolean values. If set, the passed domain information is used for routing rules only, but not for the search path logic.

networkd: rename a few Network object properties to be more like the configuration settings All booleans called dhcp_xyz are now called ".dhcp_use_xyz", to match their respective configuration file settings. This should clarify things a bit, in particular as there is a DHCP hostname that was previously called just ".hostname" because ".dhcp_hostname" was already existing as a bool. Since this confusion is removed now because the bool is called ".dhcp_use_hostname", the string field is now renamed to ".dhcp_hostname".

networkd: when filtering out duplicate domain names use DNS comparison When we collect the domain names of the various links and other sources in one ordered set, make sure to use proper DNS name comparison to filter out duplicates.

networkd: use an OrderedSet instead of Set to collect link domains For the search domain logic the order is highly relevant, hence make sure when collecting the various search domains to add them to an ordered set, so that the order between search domains of a specific link is retained.

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.

networkd: use (void) to mark ignored values Null link or netdev are handled fine. CID #1338084.

tree-wide: expose "p"-suffix unref calls in public APIs to make gcc cleanup easy 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.

networkd: improve logging

networkd: IPv6 router discovery - follow IPv6AcceptRouterAdvertisemnt= The previous behavior: When DHCPv6 was enabled, router discover was performed first, and then DHCPv6 was enabled only if the relevant flags were passed in the Router Advertisement message. Moreover, router discovery was performed even if AcceptRouterAdvertisements=false, moreover, even if router advertisements were accepted (by the kernel) the flags indicating that DHCPv6 should be performed were ignored. New behavior: If RouterAdvertisements are accepted, and either no routers are found, or an advertisement is received indicating DHCPv6 should be performed, the DHCPv6 client is started. Moreover, the DHCP option now truly enables the DHCPv6 client regardless of router discovery (though it will probably not be very useful to get a lease withotu any routes, this seems the more consistent approach). The recommended default setting should be to set DHCP=ipv4 and to leave IPv6AcceptRouterAdvertisements unset.

networkd: route - track routes

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

util-lib: move more file I/O related calls into fileio.[ch]

util-lib: split out fd-related operations into fd-util.[ch] There are more than enough to deserve their own .c file, hence move them over.

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.

networkd-manager: fix swapped arguments fixes Coverity #1328493

networkd: manager/link - only serialize once per event-loop iteration Every time the state is written out we may trigger third-party apps, so let's be a bit more careful about writing this out unnecessarily.

networkd: address - distinguish between addresses added by us and by others We only keep the addresses that we added ourselves in link->addresses, and introduce a new set link->addresses_foreign to keep addresses of unknown origin. Only functional change is that "foreign" addresses no longer prevent a link from entering "configured" state.

networkd: address - factor out address_update() Call back into link_check_ready() whenever an address state change may have made a link ready.

networkd: link - only consider configured when all addresses are ready We were considering a link configured whilst its IPv6 addresses were still tentative. Fixes issue #650.

networkd: make address_{establish,release}() static No need to expose these functions, but rather call them from address_{add,drop}.

networkd: manager - avoid unnecessary memory allocation Don't allocate Address objects only to free them again when processing rtnl events.

networkd: address - store active addresses in a Set rather than a List We need to be able to look these things up quickly as we will be updating them continuously and there can in principle be many of them.

networkd: address - process in manager.c rather than link.c

networkd: manager - free bus after own objects Freeing links/addresses may trigger sending signals over the bus, so let's make sure the bus stays around until our own objects have been freed.

basic: rework virtualization detection API Introduce a proper enum, and don't pass around string ids anymore. This simplifies things quite a bit, and makes virtualization detection more similar to architecture detection.

networkd: adjust error codes for nonexisting DHCP data Commit 0339cd770 changed libsystemd-network's error code for missing DHCP lease data from ENOENT to ENODATA. Adjust networkd accordingly. This fixes interfaces being stuck in "degraded/configuring" mode forever. https://github.com/systemd/systemd/issues/1147

networkd: s/now/know

networkd: make sure we remove udev fd from epoll *before* closing it Otherwise we'll try to remove an invalid fd from epoll all the time.

networkd: propagate DNS/NTP server from uplink to dhcp server When handing out DHCP leases, try to propagate DNS/NTP server information from "uplink". The "uplink" is automatically determined as the network interface with the highest priority default route on it.

networkd: split up networkd.h into per-object header files No functional changes, just moving definitions into separate header files.

networkd: let's uppercase the first character in log messages Let's try to generate log messages that resemble english language sentences, hence uppercase the first character.

tree-wide: fix indentation

tree-wide: port everything over to fflush_and_check() Some places invoked fflush() directly with their own manual error checking, let's unify all that by using fflush_and_check(). This also unifies the general error paths of fflush()+rename() file writers.

sd-netlink: rename from sd-rtnl

sd-rtnl: make joining broadcast groups implicit

Revert "networkd: create "kernel" setting for IPForwarding"

networkd: create "kernel" setting for IPForwarding In 5a8bcb674f71a20e95df55319b34c556638378ce, IPForwarding was introduced to set forwarding flags on interfaces in .network files. networkd sets forwarding options regardless of the previous setting, even if it was set by e.g. sysctl. This commit creates a new option for IPForwarding, "kernel", that preserves the sysctl settings rather than always setting them. See https://bugs.freedesktop.org/show_bug.cgi?id=89509 for the initial bug report.

sd-bus: drop bus parameter from message callback prototype 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().

networkd: improve logging when processing links and addresses

remove unused includes This patch removes includes that are not used. The removals were found with include-what-you-use which checks if any of the symbols from a header is in use.

networkd: don't do exit-on-idle if there is something wrong with the dbus connection Just fall back to plain old event loop in this (highly unlikely) case. In the glorious future when kdbus is upstream we can of course drop all this.

networkd: add basic org.freedesktop.network1.Network interface

networkd: add network_get_by_name

networkd: move the connection to the bus out of manager_new (again) This would otherwise make the tests fail as we cannot grab the bus name.

networkd: exit on idle We will be woken up on rtnl or dbus activity, so let's just quit if some time has passed and that is the only thing that can happen. Note that we will always stay around if we expect network activity (e.g. DHCP is enabled), as we are not restarted on that.

networkd: add basic dbus API Only the very basics, more to come. For now: $ busctl tree org.freedesktop.network1 └─/org/freedesktop/network1 └─/org/freedesktop/network1/link ├─/org/freedesktop/network1/link/1 ├─/org/freedesktop/network1/link/2 ├─/org/freedesktop/network1/link/3 ├─/org/freedesktop/network1/link/4 ├─/org/freedesktop/network1/link/5 ├─/org/freedesktop/network1/link/6 ├─/org/freedesktop/network1/link/7 ├─/org/freedesktop/network1/link/8 └─/org/freedesktop/network1/link/9 $ busctl introspect org.freedesktop.network1 /org/freedesktop/network1 NAME TYPE SIGNATURE RESULT/VALUE FLAGS org.freedesktop.network1.Manager interface - - - .OperationalState property s "carrier" emits-change $ busctl introspect org.freedesktop.network1 /org/freedesktop/network1/link/1 NAME TYPE SIGNATURE RESULT/VALUE FLAGS org.freedesktop.network1.Link interface - - - .AdministrativeState property s "unmanaged" emits-change .OperationalState property s "carrier" emits-change

networkd: don't warn about missing links unnecessarily If we get a NEWLINK + NEWADDR between enumerating the links and enumerating the addresses, we would get a warning that the link corresponding to the address does not exist. This is a false warning as both the NEWLINK and NEWADDR would be processed after enumerating completed, so drop it.

networkd: refactor socket activation a bit

networkd: handle suspend events

networkd: minor simplification Let's return the fd we found as return value in systemd_netlink_fd(), instead of using call-by-reference.

networkd: support socket activation Still keep the non-socket activation code around for starting from the commandline, but will likely drop that too in the future.

networkd: make IP forwarding for IPv4 and IPv6 individually configurable

networkd: introduce an AddressFamilyBoolean enum type This introduces am AddressFamilyBoolean type that works more or less like a booleaan, but can optionally turn on/off things for ipv4 and ipv6 independently. THis also ports the DHCP field over to it.

networkd: failing to track links is a serious problem so log at warning level rather than debug

networkd: manager - enumerate addresses globally, rather than per-link The kernel always returns all addresses, rather than only for the given link, so let's only enumerate once.

treewide: yet more log_*_errno + return simplifications 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.

treewide: more log_*_errno() conversions, multiline calls Basically: find . -name '*.[ch]' | while read f; do perl -i.mmm -e \ 'local $/; local $_=<>; s/log_(debug|info|notice|warning|error|emergency)\("([^"]*)%s"([^;]*),\s*strerror\(-?([->a-zA-Z_]+)\)\);/log_\1_errno(\4, "\2%m"\3);/gms;print;' \ $f; done Plus manual indentation fixups.

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().

networkd: fix kernel rtnl receive buffer overrun error We got the following error when running systemd on a device with many ports: "rtnl: kernel receive buffer overrun Event source 'rtnl-receive-message' returned error, disabling: No buffer space available" I think the kernel socket receive buffer queue should be increased. The default value is taken from: "/proc/sys/net/core/rmem_default", but we can overwrite it using SO_RCVBUF socket option. This is already done in networkd for other sockets. For example, the bus socket (sd-bus/bus-socket.c) has a receive queue of 8MB. In our case, the default is 208KB. Increasing the buffer receive queue for manager socket to 512KB should be enough to get rid of the above error. [tomegun: bump the limit even higher to 8M]

sd-event: rename sd_event_source_set_name() to sd_event_source_get_name() To mirror the recent name change of the concept for sd_bus objects, follow the same logic for sd_event_source objects, too.

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.

networkd: remove vestigial event sources 187fe1db took advantage of floating events, but didn't remove pointers it made superfluous.

sd-event: name event sources used in libraries This should help in debugging failing event sources.

sd-network: add system-wide sd_network_get_domains() API

sd-network: rename operstates 'down' -> 'off' and 'up' -> 'no-carrier' Suggested by Lennart and Kay.

sd-network: split the operstate 'unknown' into 'down' and 'up'

networkd: split out networkd-link.h

networkd: expose a global list of DNS and NTP servers in the state file

networkd: update manager_save() to use fflush_and_check() to simplify things a bit

networkd: store ifindex as int

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.

sd-rtnl: make string returned by sd_rtnl_message_read_string() const

networkd: netdev - introduce vtable for netdev kinds Split each netdev kind into its own .h/.c.

networkd: simplify signal handling of SIGTERM/SIGINT sd-event makes handling SIGTERM/SIGINT a lot easier than it used to, let's make use of this

networkd: link - ignore missing MAC address Currently DHCP/IPv4LL only works on ethernet devices, but no reason not to otherwise manage them.

networkd: link - improve refcounting We failed to take a ref when waiting for udev synchronization. Fix that and also make unreffing in callbacks simpler throughout by using _cleanup_ macros. Fixes <https://bugs.freedesktop.org/show_bug.cgi?id=80556>.

networkd: add address pool support When an address is configured to be all zeroes, networkd will now automatically find a locally unused network of the right size from a list of pre-configured pools. Currently those pools are 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 and fc00::/7, i.e. the network ranges for private networks. They are compiled in, but should be configurable eventually. This allows applying the same configuration to a large number of interfaces with each time a different IP range block, and management of these IP ranges is fully automatic. When allocating an address range from the pool it is made sure the range is not used otherwise.

networkd: split runtime config dir from state dir Configuration will be in root:root /run/systemd/network and state will be in systemd-network:systemd-network /run/systemd/netif This matches what we do for logind's seat/session state.

networkd: drop CAP_SYS_MODULE Rely on modules being built-in or autoloaded on-demand. As networkd is a network facing service, we want to limits its capabilities, as much as possible. Also, we may not have CAP_SYS_MODULE in a container, and we want networkd to work the same there. Module autoloading does not always work, but should be fixed by the kernel patch f98f89a0104454f35a: 'net: tunnels - enable module autoloading', which is currently in net-next and which people may consider backporting if they want tunneling support without compiling in the modules. Early adopters may also use a module-load.d snippet and order systemd-modules-load.service before networkd to force the module loading of tunneling modules. This sholud fix the various build issues people have reported.

networkd/sd-network: extend operational states Expose states 'degraded' or 'routable' if a link has a site/link-local or a routable address, respectively.

resolved: add daemon to manage resolv.conf Also remove the equivalent functionality from networkd.

networkd: manager - read fallback DNS servers from config file We will still use the compiled-in defaults if no DNS entry exists in the config file.

networkd: network - store DNS servers in List rather than Set This way we preserve the order of preference.

networkd: hardcode a set of default dns servers Similarly to NTP servers, this can be set at compile-time.

networkd: manager - don't leak kmod context Also, keep the kmod_new internal to networkd-manager.c

networkd: introduce ipip tunnel This patch enables basic ipip tunnel support. It works with kernel module ipip example conf: file: ipip.netdev [NetDev] Name=ipip-tun Kind=ipip MTUBytes=1480 [Tunnel] Local=192.168.223.238 Remote=192.169.224.239 TTL=64 file: ipip.network [Match] Name=em1 [Network] Tunnel=ipip-tun [tomegun: - drop unused variable - take ref when enslaving]

networkd: get preexiting addresses when a link is added

networkd: listen for address changes This is proof-of-concept only, as we only log the changes but don't do anything with it.

rtnl: change from bitmask to enum for rtnl groups The bitmask is deprecated in the kernel, so move to the new interface. At the moment this does not make a difference for us, but it avoids having to change the API in the future.

networkd: manager - initialize variables

networkd: manager - refactor link tracking a bit

networkd: manager - drop links and netdevs when we receive DELLINK

networkd: introduce refcounting for Links and NetDevs

sd-network: expose global operational state

networkd: manager - add a bit of debug output to udev ADD events

networkd: tie links to rtnl rather than udev This essentially swaps the roles of rtnl and udev in networkd. After this change libudev is only used for waiting for udev to initialize devices and to get udev-specific information needed for some [Match] attributes. This in particular simplifies the code in containers where udev is not really useful, but also simplifies things and reduces round-trips in the non-container case.

networkd: rewind rtnl message between passing it to functions This makes updating link status on netdev links work again.

networkd: fix use-after-free Free networks before links (the reverse of creation order).

networkd: netdev - improve logging when setting ifindex

networkd: netdev - verify that newlink messages has the expected kind We match 'newlink' messages with expected netdev's based on their names. Now also make sure that the receieved link has the expected kind.

networkd: update mac address in clients when it changes Pass the mac address on to ipv4ll and dhcp clients so they always have up-to-date information, and may react appropriately to the change. Also drop setting the mac address from uevent, and only log when the address actually changes.

networkd: fix typo It's HAVE_SPLIT_USR not HAVE_SPLIT_USER

networkd: allow more than one static DNS server

networkd: fix creation of runtime dirs at startup This allows us to drop the repeated attempted creations of the runtime dirs during runtime.

sd-rtnl/networkd: use new rtnl_message_read() API and drop helper With the new sd_rtnl_message_read_string(), there is no longer a need for rtnl_message_get_ifname().

networkd: handle SIGINT and SIGTERM

api: in constructor function calls, always put the returned object pointer first (or second) Previously the returned object of constructor functions where sometimes returned as last, sometimes as first and sometimes as second parameter. Let's clean this up a bit. Here are the new rules: 1. The object the new object is derived from is put first, if there is any 2. The object we are creating will be returned in the next arguments 3. This is followed by any additional arguments Rationale: For functions that operate on an object we always put that object first. Constructors should probably not be too different in this regard. Also, if the additional parameters might want to use varargs which suggests to put them last. Note that this new scheme only applies to constructor functions, not to all other functions. We do give a lot of freedom for those. Note that this commit only changes the order of the new functions we added, for old ones we accept the wrong order and leave it like that.

networkd: refactor link_add() :( Don't set set **ret when returning r < 0, as matching on the errno may easily give false positives in the future leading to null pointer dereference. Reported-by: David Herrmann <dh.herrmann@gmail.com>

networkd: correctly handle manager_free(NULL)

networkd: work inside containers Udev does not run in containers, so instead of relying on it to tell us when a network device is ready to be used by networkd, we simply assume that any device was fully initialized before being added to the container.

networkd: netdev - rename Netdev to NetDev Both in the configuration file format and everywhere else in the code.

sd-dhcp-client: split sd_dhcp_lease from sd_dhcp_client This allows us users of the library to keep copies of old leases. This is used by networkd to know what addresses to drop (if any) when the lease expires. In the future this may be used by DNAv4 and sd-dhcp-server.

networkd: netdev - reduce chance of race when receiving netdev's ifindex When creating a new link, the kernel will not inform us about the new ifindex in its ack. We have to listen for newly created devices and deduce the new ifindex by matching on the ifname. We used to do this by waiting for a new device from libudev, but that is asking for trouble, as udev will happily rename the device before handing it to us. Listen on rtnl instead, the chance of the name being changed before reaching us is much smaller (if not nil). Kernel patch in the works to make this unneccessary.

networkd: add basic bonding support Refactor bridging support to be generic netdev support and extend it to cover bonding as well.

sd-dhcp-client/networkd: add domainname support

networkd: don't hard depend on system bus We may not have a dbus daemon in the initrd (until we can rely on kdbus). In this case, simply ignore any attempts at using the bus. There is only one user for now, but surely more to come. In order to work reliably in the real root without kdbus, but at the same time don't delay boot when kdbus is in use, order ourselves after dbus.service.

networkd: resolv.conf - reword comment Take into account that users may want to use resolvconf(8), or similar. Also, avoid repeated calls to fputs().

networkd: resolv.conf - extend the comment a bit

sd-dhcp-client: refactor DNS support Rather than keeping an array of pointers to addresses, just keep an array of addresses.

sd-dhcp-client/networkd: add transient hostname support

networkd: fix wording

networkd: generate resolv.conf This adds support to generate a basic resolv.conf in /run/systemd/network. This file will not take any effect unless a symlink is created from /etc/resolv.conf. Nameservers received over DHCP takes precedence over statically configured ones. Note: /etc/resolv.conf is severely limited, so in the future we will likely rather provide a much more powerfull nss plugin (or something to that effect), but this should allow current users to function without any loss of functionality.

No need to canonicalize fixed paths

networkd: link hash uses 64, not 32 bit keys

networkd: print the ifindex of added links This debug information may be useful when comapring to dropped rtnetlink messages.

networkd: improve logging This gives a bit better messages when a link is added twice.

networkd: add some debug info about notifications we ignore

networkd: only track state of links we are managing If a network is not (yet) set for a link, we do not care about its state (as we anyway don't know what to do with it).

networkd: improve logging Remove redundant messages, add some debugging ones and make wording more uniform.

core,logind,networkd: check for udev device initialization via enumeration matches Instead of checking each device after we got it, check wuth an enumeration filter instead, to make it more efficient.

core,logind,networkd: don't pick up devices from udev before they finished udev initialization Managers shouldn't pick up the devices the manage before udev finished initialization, hence check explicitly for that.

networkd: rename link_update_flags to link_update We are likely to track more than the flags in the future.

event: be more conservative when returning errors from event handler callbacks We really should return errors from event handlers if we have a continous problem and don't know any other solution.

event: hook up sd-event with the service watchdog logic Adds a new call sd_event_set_watchdog() that can be used to hook up the event loop with the watchdog supervision logic of systemd. If enabled and $WATCHDOG_USEC is set the event loop will ping the invoking systemd daemon right after coming back from epoll_wait() but not more often than $WATCHDOG_USEC/4. The epoll_wait() will sleep no longer than $WATCHDOG_USEC/4*3, to make sure the service manager is called in time. This means that setting WatchdogSec= in a .service file and calling sd_event_set_watchdog() in your daemon is enough to hook it up with the watchdog logic.

networkd: add link-sense and simplify state-machine a bit This listens to rtnetlink for changes to IFF_UP and IFF_LOWER_UP (link sense). The latter is simply logged at the moment, but will be useful once we add dhcp support.

networkd: add bridge support A bridge is specified in a .netdev file with a section [Bridge] and at least the entry Name=. A link may be joined to a bridge if the .network applied to it has a Bridge= entry giving the name of the bridge in its [Network] section. We eagerly create all bridges on startup, and links are added to bridges as soon as they both appear.

networkd: don't filter on udev tags This removed the requirement for devices to be tagged with 'systemd-networkd' before they will be visible to networkd. Still, as by default we don't ship any .network files, network devices will simply be tracked, but not touched, unless the admin configures things explicitly.

networkd: make sure Links and Networks are freed

networkd: make all calls async

bus: introduce concept of a "default" event loop per-thread and make use of it everywhere Try to emphasize a bit that there should be a mapping between event loops and threads, hence introduce a logic that there's one "default" event loop for each thread, that can be queried via "sd_event_default()".

networkd: add a basic network daemon This daemon listens for and configures network devices tagged with 'systemd-networkd'. By default, no devices are tagged so this daemon can safely run in parallel with existing network daemons/scripts. Networks are configured in /etc/systemd/network/*.network. The first .network file that matches a given link is applied. The matching logic is similar to the one for .link files, but additionally supports matching on interface name. The mid-term aim is to provide an alternative to ad-hoc scripts currently used in initrd's and for wired setups that don't change much (e.g., as seen on servers/and some embedded systems). Currently, static addresses and a gateway can be configured. Example .network file: [Match] Name=wlp2s0 [Network] Description=My Network Gateway=192.168.1.1 Address=192.168.1.23/24 Address=fe80::9aee:94ff:fe3f:c618/64