The link state file is always removed when networkd is stopping. So,
the deserialization logic does not work. Moreover, the ADDRESSES=
entry is not used by sd-network, so serialization is also not necessary.
Previously, the address was taken from the state file, but DHCP4_ADDRESS=
entry was dropped by 46986251d6.
Moreover, the link state file is always removed when networkd is
stopping. Let's take the address from the list of enumerated addresses.
This should not change any behavior, as currently link_free_engines() is
always called after all addresses are dropped. But the function may be
used in other places in the future. So, let's also stop the clients.
When the MAC address of a link is updated, an address on the link may
be under checking address duplication. Or, (currently such code is not
implemented yet, but) address duplication check may be restarted later.
For that case, the IPv4 ACD clients must use the new updated MAC address.
Previously, IPv4 DAD is configured in each Address object stored in
Network object. If a .network file matches multipe links, then it causes
an assertion. To prevent it, now IPv4 DAD is configured in each Address
object belogs to Link object.
In order to allow other parts of systemd-networkd to use sets/hashmaps
of Address objects, the address_hash_ops structure needs to be made
available to them.
If e.g., an [Address] section has an invalid setting, then
previously assigned settings in the section is freed, and
only later settings are stored. That may cause partially broken
section stored in Network object.
This makes if an invalid setting is found, then set 'invalid' flag
instead of freeing it. And invalid sections are dropped later by
network_verify().
This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
This makes most header files easier to look at. Also Emacs gets really
slow when browsing through large sections of overly long prototypes,
which is much improved by this macro.
We should probably not do something similar with too many other cases,
as macros like this might help readability for some, but make it worse
for others. But I think given the complexity of this specific prototype
and how often we use it, it's worth doing.
This drops a good number of type-specific _cleanup_ macros, and patches
all users to just use the generic ones.
In most recent code we abstained from defining type-specific macros, and
this basically removes all those added already, with the exception of
the really low-level ones.
Having explicit macros for this is not too useful, as the expression
without the extra macro is generally just 2ch wider. We should generally
emphesize generic code, unless there are really good reasons for
specific code, hence let's follow this in this case too.
Note that _cleanup_free_ and similar really low-level, libc'ish, Linux
API'ish macros continue to be defined, only the really high-level OO
ones are dropped. From now on this should really be the rule: for really
low-level stuff, such as memory allocation, fd handling and so one, go
ahead and define explicit per-type macros, but for high-level, specific
program code, just use the generic _cleanup_() macro directly, in order
to keep things simple and as readable as possible for the uninitiated.
Note that before this patch some of the APIs (notable libudev ones) were
already used with the high-level macros at some places and with the
generic _cleanup_ macro at others. With this patch we hence unify on the
latter.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
Add variables for enabling Router Advertisements, router lifetime as
well as managed and other information flags indicating use of DHCPv6.
Add configuration of default router preferences as defined in RFC 4191.
IPv6PrefixDelegation in the [Network] section has to be set in order
to enable prefix delegation. The rest of the prefix delegation values
are stored in the [IPv6PrefixDelegation] section. The host will act as
a default router if it is given a non-zero lifetime with
RouterLifetimeSec. Managed and OtherInformation booleans set the level
of DHCPv6 support, and the RouterPreference configures the router's
preference between low, medium and high. Words 'normal' and 'default'
are added as synonyms for 'medium' just to make configuration simpler.
This adds a section like the following to .network configuration files:
[Network]
IPv6PrefixDelegation=true
[IPv6PrefixDelegation]
RouterLifetimeSec=2000
Managed=false
OtherInformation=true
RouterPreference=medium
Support zero or more [IPv6Prefix] sections in the network configuration
files. Each section can have one Prefix=<subnet>[/<prefixlength>]
option, with the preferred and valid lifetimes specified by
ValidLifetimeSec and PreferredLifetimeSec measured in seconds, and
with onlink and address autoconfiguration booleans specified by
OnLink and AddressAutoconfiguration variables.
This adds a section like the following to .network configuration files:
[IPv6Prefix]
Prefix=2001:db8:dead:beef::/64
OnLink=true
AddressAutoconfiguration=true
ValidLifetimeSec=1500
PreferredLifetimeSec=1000