The REPLY of a TP-Link router (WR400 v4.20) ends with a 0 option
that has a bogus length.
When subtracting the length from the remaining length, we get an
underflow (remaining `len` is 3, option len is 4).
To get a working DHCP response, consider 0 (Reserved) an end marker.
If we did not enable downstream interfaces yet but have IA_PD enabled
or if we did not configure an interface for IA_NA but have the module
enabled, don't discard the DHCP reply.
If a server does not support an option it will respond with an error
code.
Prefix delegation used to be the only supported feature of our DHCPv6
client, but by now it also supports MUD, DNS recursive name servers and
IA_NA is on the horizon. So it makes sense to make IA_PD an optional
module like all those other features are as well.
There is no real reason for that pseudo-module to use the `gnrc_`
prefix. Neither does it need GNRC-components (except, but optionally, as
a network stack of course), nor is it implemented with in the GNRC
network stack.
This changes the prefixes of the symbols generated from USEMODULE and
USEPKG variables. The changes are as follow:
KCONFIG_MODULE_ => KCONFIG_USEMODULE_
KCONFIG_PKG_ => KCONFIG_USEPKG_
MODULE_ => USEMODULE_
PKG_ => USEPKG_
The DHCPv6 server might send reponses multiple times.
The DHCPv6 client will only handle the first response, if additional
responses are comming in they are left in the RX queue.
That results in the client always reading the response of a previous
transaction on any subsequent transactions.
In this case the client will try again, creating a new transaction - that
will again only read the previous response.
To fix this, discard previous responses by flushing the RX queue before
sending a new message to the DHCPv6 server.
fixes#13834
There were two subtle bugs that prevented the DHCPv6 client to request
multiple prefixes for different interfaces.
- `dhcpv6_client_req_ia_pd()` would fill up *all* leases with the same interface
- `_parse_reply()` would return after parsing the first answer
With this patch, `gnrc_border_router` gets a prefix on both interfaces of the at86rf215.
This implements a client for DHCPv6 IA_PD (Identity Association for
Prefix Delegation). Goal was to have a IETF-compliant alternative to
UHCP. The implementation was based on RFC 8415.
