With these patches applied, networkd is successfully able to get an
address from a DHCP server on an IPoIB interface.
1)
Makes networkd pass the actual interface type to the dhcp client,
instead of hardcoding it to Ethernet.
2)
Fixes some issues in handling the larger (20 Byte) IB MAC addresses in
the dhcp code.
3)
Add a new field to networkds Link struct, which holds the interface
broadcast address.
3.1)
Modify the DHCP code to also expect the broadcast address as parameter.
On an Ethernet-Interface the Broadcast address never changes and is always
all 6 bytes set to 0xFF.
On an IB one however it is not neccesarily always the same, thus
fetching the actual address from the interface is neccesary.
4)
Only the last 8 bytes of an IB MAC are stable, so when using an IB MAC to
generate a client ID, only pass those 8 bytes.
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.
IPServiceType set to CS6 (network control) causes problems on some old
network setups that continue to interpret the field as IP TOS.
Make DHCP work on such networks by allowing this field to be set to
CS4 (Realtime) instead, as this maps to IPTOS_LOWDELAY.
Signed-off-by: Siddharth Chandrasekaran <csiddharth@vmware.com>
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.
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.
If a client sends a DECLINE or a server sends a NAK, they can include
a string with a message to explain the error. Parse this and print it
at debug level.
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.
- 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");
Like Infiniband. See RFC 4390 section 2.1 for details on DHCP
and Infiniband; chaddr is zeroed, hlen is set to 0, and htype
is set to ARPHRD_INFINIBAND because IB hardware addresses
are 20 bytes in length.
Check that received DHCP packets actually include our MAC address in
chaddr field. BPF interpreter has 32 bit wide registers but MAC address
is 48 bits long so we have to do check in two steps.
Let's keep this behavior consistent across our libraries.
In order to keep the refcounting working, a DONT_DESTROY macro similar
to the one in sd-bus was introduced.
For efficiency, we group bytes together before adding them up. This
is guaranteed to always work (regardless of the byte order) as long
as the i-th byte in each group lign up with the i-th byte in each
other group.
On big-endian machines this broke when handling the trailing few bytes
which did not make up a full group of 4 bytes. This patch fixes the
problem by explicitly creating a 4 byte zero-padded group out of the
trailing bytes.
Reported and tested by Thomas Ritter <th.ritter@gmx.at>.
Store a pointer to the options in the DHCPMessage struct, and pass
this together with an offset around, rather than a uint8_t**.
This avoids us having to (re)compute the pointer; and changes
dhcp_option_append from adjusting both the pointer to the next
option and the remaining size of the options, to just adjusting
the current offset.
This makes the code a bit simpler to follow IMHO, but there should
be no functional change.
Improve the checksum computation by using 64 bit integers instead of the 16 bit
integers in the existing implementation. This change speeds up the computation
with approximately 78% both on 64 bit and 32 bit systems.
Please see RFC 1071 for details.
Try a bit harder to make the kernel drop packets not for us. This should reduce
the number of wakeups from n^2 to n in the number of dhcp clients, which admittedly
only makes a differenc in very extreme cases.
