Currently, the received hostname is not used for assigning an address to
the host, or options in the subsequent reply message. But, the parsed
hostname is exposed through DBus, and possibly Varlink in the future.
Let's ignore spurious hostname.
We oftem save parsed DHCP options into a file, or expose them
through DBus or Varlink. In such case, control characters or non-UTF8
characters may cause many kind of unexpected errors. In general, a DHCP
message that have string options with spurious characters is mostly
malformed or broken. Let's refuse them.
This also makes dhcp_option_parse_string() do not free 'ret' argument,
to follow our usual coding style. So, callers now need to free the
pre-exisitng string if necessary.
Fixes#31708.
Add functions serializing LLDP neighbors to JSON (JsonVariant).
The entry contains a chassis id, system name and port id of the remote
neighbor. Also it possibly contains an integer coding the enabled system
capabilities and port description.
This effectively reverts 9175002864.
The retrans time field in RA message is for neighbor solicitation,
and the commit d4c8de21a0 makes the value
assigned to the correct sysctl property.
Let's deprecate the option, and drop the redundant functions.
Previously, the function supports packets without IPv6 sender address
for unit tests. However, now unit tests use their own version of
icmp6_receive(). Hence, let's make the check more strict.
- split out radv_setup_recv_event(),
- slightly update log messages,
- use DIV_ROUND_UP(),
- use structured initializer more.
No functional change, just preparation for later commits.
- update several log messages,
- use event_reset_time_relative(),
- split out ndisc_setup_recv_event() and ndisc_setup_timer().
No functional change, just refactoring and preparation for later commits.
The send-release option only affects to the client when STOPPING. There
is no reason to do not allow this option to be set while the client is
running.
An user might want to delay the decision of sending a RELEASE message to
a later stage where the client is already running.
The RA's Retransmission Timer field was being ignored. This resolves the IPv6
Core Conformance test, v6LC.2.1.5 [1].
Retransmission Timer is a 32-bit unsigned integer. The time, in milliseconds,
between retransmitted Neighbor Solicitation messages. Used by the Address
Resolution and Neighbor Unreachability Detection (NUD) algorithm.
Support setting a default value for the neighbour retransmission timer value with:
[Network]
IPv6RetransmissionTimeSec=<int>
By default, upon receiving a Router Advertisement with the Retransmission Timer
field set to a non-zero value, it will update the kernel's retransmit timer value.
To disable this behaviour, configure the UseIPv6RetransmissionTime= under the
[IPv6AcceptRA] section.
[IPv6AcceptRA]
UseIPv6RetransmissionTime=<bool>
RFC4861: Neighbor Discovery in IPv6
* Section 4.2 RA Message Format.
* Section 6.3.4 Processing Received Router Advertisements
A Router Advertisement field (e.g., Cur Hop Limit, Reachable Time,
and Retrans Timer) may contain a value denoting that it is
unspecified. In such cases, the parameter should be ignored and the
host should continue using whatever value it is already using. In
particular, a host MUST NOT interpret the unspecified value as
meaning change back to the default value that was in use before the
first Router Advertisement was received.
The RetransTimer variable SHOULD be copied from the Retrans Timer
field, if the received value is non-zero.
References
[1] IPv6 Core Conformance Spec (PDF)
The data may be from user input or file. We usually use assertion for
programming error. Hence, using assert is not a good choise there.
Preparation for later commits.
Currently, networkd does not change pool size dynamically, so this
should not change behavior. But if networkd does that, then forgetting
leases causes that an address still used by a client may be assigned to
another host.
- Even if we found a matching static lease, check if there is no
conflicting lease.
- Accept an address request that is different from the previous one.
- Also return NAK if the server address is requested.
Yu Watanabe
Evgeny Vereshchagin
Tomáš Pecka
Luca Boccassi
Martin Ivicic
Fernando Fernandez Mancera
Matt Muggeridge
Andres Beltran
Mike Yuan