The long name is just too hard to type. We generally should avoid using
acronyms too liberally, if they aren't established enough, but it appears that
"RA" is known well enough. Internally we call the option "ipv6_accept_ra"
anyway, and the kernel also exposes it under this name. Hence, let's rename the
IPv6AcceptRouterAdvertisements= setting and the
[IPv6AcceptRouterAdvertisements] section to IPv6AcceptRA= and [IPv6AcceptRA].
The old setting IPv6AcceptRouterAdvertisements= is kept for compatibility with
older configuration. (However the section [IPv6AcceptRouterAdvertisements] is
not, as it was never available in a published version of systemd.
This reworks sd-ndisc and networkd substantially to support IPv6 RA much more
comprehensively. Since the API is extended quite a bit networkd has been ported
over too, and the patch is not as straight-forward as one could wish. The
rework includes:
- Support for DNSSL, RDNSS and RA routing options in sd-ndisc and networkd. Two
new configuration options have been added to networkd to make this
configurable.
- sd-ndisc now exposes an sd_ndisc_router object that encapsulates a full RA
message, and has direct, friendly acessor functions for the singleton RA
properties, as well as an iterative interface to iterate through known and
unsupported options. The router object may either be retrieved from the wire,
or generated from raw data. In many ways the sd-ndisc API now matches the
sd-lldp API, except that no implicit database of seen data is kept. (Note
that sd-ndisc actually had a half-written, but unused implementaiton of such
a store, which is removed now.)
- sd-ndisc will now collect the reception timestamps of RA, which is useful to
make sd_ndisc_router fully descriptive of what it covers.
Fixes: #1079
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>
Separate fields are replaced with a struct.
Second second duid type field is removed. The first field was used to carry
the result of DUIDType= configuration, and the second was either a copy of
this, or contained the type extracted from DuidRawData. The semantics are changed
so that the type specified in DUIDType is always used. DUIDRawData= no longer
overrides the type setting.
The networkd code is now more constrained than the sd-dhcp code:
DUIDRawData cannot have 0 length, length 0 is treated the same as unsetting.
Likewise, it is not possible to set a DUIDType=0. If it ever becomes necessary
to set type=0 or a zero-length duid, the code can be changed to support that.
Nevertheless, I think that's unlikely.
This addresses #3127 § 1 and 3.
v2:
- rename DUID.duid, DUID.duid_len to DUID.raw_data, DUID.raw_data_len
Let's move DUID configuration into the [DHCP] section, since it only makes
sense in a DHCP context, and should be close to the configuration of
ClientIdentifier= and suchlike.
This really shouldn't be a section of its own, we don't have any for any of our
other per-protocol specific identifiers...
Follow-up for #2890#2943
IPv6 protocol requires a minimum MTU of 1280 bytes on the interface.
This fixes#3046.
Introduce helper link_ipv6_enabled() to figure out whether IPV6 is enabled.
Introduce network_has_static_ipv6_addresses() to find out if any static
ipv6 address configured.
If IPv6 is not configured on any interface that is SLAAC, DHCPv6 and static
IPv6 addresses not configured, then IPv6 will be automatically disabled for that
interface, that is we write "1" to /proc/sys/net/ipv6/conf//disable_ipv6.
This way "networkctl status" becomes a bit more useful by default, as router
information is just visible, without any further configuration.
LLDP reception is fully passive and relatively low simple and low traffic,
hence this should be safe to enable by default.
This reworks the sd-lldp substantially, simplifying things on one hand, and
extending the logic a bit on the other.
Specifically:
- Besides the sd_lldp object only one other object is maintained now,
sd_lldp_neighbor. It's used both as storage for literal LLDP packets, and for
maintainging info about peers in the database. Separation between packet, TLV
and chassis data is not maintained anymore. This should be a major
simplification.
- The sd-lldp API has been extended so that a couple of per-neighbor fields may
be queried directly, without iterating through the object. Other fields that
may appear multiple times, OTOH have to be iterated through.
- The maximum number of entries in the neighbor database is now configurable
during runtime.
- The generation of callbacks from sd_lldp objects is more restricted:
callbacks are only invoked when actual data changed.
- The TTL information is now hooked with a timer event, so that removals from
the neighbor database due to TTLs now result in a callback event.
- Querying LLDP neighbor database will now return a strictly ordered array, to
guarantee stability.
- A "capabilities" mask may now be configured, that selects what type of LLDP
neighbor data is collected. This may be used to restrict collection of LLDP
info about routers instead of all neighbors. This is now exposed via
networkd's LLDP= setting.
- sd-lldp's API to serialize the collected data to text files has been removed.
Instead, there's now an API to extract the raw binary data from LLDP neighbor
objects, as well as one to convert this raw binary data back to an LLDP
neighbor object. networkd will save this raw binary data to /run now, and the
client side can simply parse the information.
- support for parsing the more exotic TLVs has been removed, since we are not
using that. Instead there are now APIs to extract the raw data from TLVs.
Given how easy it is to parse the TLVs clients should do so now directly
instead of relying on our APIs for that.
- A lot of the APIs that parse out LLDP strings have been simplified so that
they actually return strings, instead of char arrays with a length. To deal
with possibly dangerous characters the strings are escaped if needed.
- APIs to extract and format the chassis and port IDs as strings has been
added.
- lldp.h has been simplified a lot. The enums are anonymous now, since they
were never used as enums, but simply as constants. Most definitions we don't
actually use ourselves have eben removed.
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.
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".
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.
For now only deserialize some basic state and the applied addresses.
When a link is added, try to deserialize it's state from /run. This
is relevant only when networkd is restarted at runtime.
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.
- Rely everywhere that we use abs() on the error code passed in anyway,
thus don't need to explicitly negate what we pass in
- Never attach synthetic error number information to log messages. Only
log about errors we *receive* with the error number we got there,
don't log any synthetic error, that don#t even propagate, but just eat
up.
- Be more careful with attaching exactly the error we get, instead of
errno or unrelated errors randomly.
- Fix one occasion where the error number and line number got swapped.
- Make sure we never tape over OOM issues, or inability to resolve
specifiers
