This is an attempt to clean-up the DHCP lease server type code a bit. We
now strictly use the same enum everywhere, and store server info in an
array. Moreover, we use the same nomenclature everywhere.
This only makes the changes in the sd-dhcp code. The networkd code is
untouched so far (but should be fixed up like this too. But it's more
complicated since this would then touch actual settings in .network
files).
Note that this also changes some field names in serialized lease files.
But given that these field names have not been part of a released
version of systemd yet, such a change should be ok.
This is pure renaming/refactoring, shouldn't actually change any
behaviour.
Let's use size_t for numbers of entries in memory.
Let's use const wherever appropriate.
Drop `_server` suffix from function name where we don't have it for
similar other cases.
When specifying `DHCPv4.SendOption=`, it is used by systemd-networkd to
set the value of that option within the DHCP request that is sent out.
This differs to setting `DHCPServer.SendOption=`, which will place all
the options together as suboptions into the vendor-specific information
(code 43) option.
This commit adds two new config options, `DHCPv4.SendVendorOption=` and
`DHCPServer.SendVendorOption=`. These both have the behaviour of the old
`DHCPServer.SendOption=` flag, and set the value of the suboption in the
vendor-specific information option.
The behaviour of `DHCPServer.SendOption=` is then changed to reflect
that of `DHCPv4.SendOption=`. It will set the value of the corresponding
option in the DHCP request.
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.
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 an option to disable appending DHCP option 3 (Router) to the DHCP
OFFER and ACK packets.
This commit adds the boolean option EmitRouter= for the [DHCPServer]
section in .network files.
Rationale: On embedded devices, it is very useful to have a DHCP server
running on an USB OTG ethernet gadget interface to avoid manual setup on
the client PCs, but it should only serve IP addresses, no route(r)s.
Otherwise, Windows clients experience network connectivity issues, due
to them using the address set in DHCP option 3 as default gateway.
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Usually, we place the #pragma once before the copyright blurb in header files,
but in a few cases we didn't. Move those around, so that we do the same thing
everywhere.
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.
All our hash functions are based on siphash24(), factor out
siphash_init() and siphash24_finalize() and pass the siphash
state to the hash functions rather than the hash key.
This simplifies the hash functions, and in particular makes
composition simpler as calling siphash24_compress() repeatedly
on separate chunks of input has the same effect as first
concatenating the input and then calling siphash23_compress()
on the result.
Merge sd_dhcp_server_set_address() and sd_dhcp_server_set_lease_pool() into
sd_dhcp_server_configure_pool() as the behavior of the two former depends
on the order they are called in. The flexibility is not needed, so let's
just do this in one call.
Rather than having all clients attempt to get the same leases (starting at the
beginning of the pool), make each client star at a random offset into the pool
determined by their client id. This greatly increases the chances of a given
client receiving the same IP address even though both the client and server
have lost any lease information (and distinct server instances handing out
the same leases).
- Rename log_meta() → log_internal(), to follow naming scheme of most
other log functions that are usually invoked through macros, but never
directly.
- Rename log_info_object() to log_object_info(), simply because the
object should be before any other parameters, to follow OO-style
programming style.
This change has two benefits:
- The format string %m will now resolve to the specified error (or to
errno if the specified error is 0. This allows getting rid of a ton of
strerror() invocations, a function that is not thread-safe.
- The specified error can be passed to the journal in the ERRNO= field.
Now of course, we just need somebody to convert all cases of this:
log_error("Something happened: %s", strerror(-r));
into thus:
log_error_errno(-r, "Something happened: %m");
