Since we now have the possibility to request prefixes to be delegated
without corresponding IPv6 addresses, it does not make sense to store
lease T1 and T2 timeouts in the otherwise unused IA_NA structure.
Therefore lease timeouts T1 and T2 are moved to the DHCPv6 client
structure, as there will be only one set of stateful timeouts required
by RFC 7550, Section 4.3.
Add function to fetch the IAID for the delegated IA_PD prefix. In
order to keep things simple in the implemntation, the same IAID
is used with IA_NA addresses and IA_PD prefixes. But the DHCPv6
server can choose to return only IA_PD prefixes, and the client
can nowadays omit requesting of IA_NA addresses. Since the function
fetching said IAID from the lease looks only for IA_NA ones, it
will return an empty IAID, which of course does not match the one
set for prefixes.
Fix this by adding a function returning the IAID for the prefix.
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.
Ever since the initial implementation in 631bbe7129,
client_parse_message() was supposed to check that the message contains exactly
one serverid. The check that no more than one is given was implemented
correctly, but the check that at least one is given was not. Simplify the whole
thing by making dhcp6_lease_get_serverid() return an error if the id is not
set, and do not require the arguments to be present if the contents of the id
are not needed.
Although the SNTP option specified in RFC 4075 has been deprecated, some
servers are still sending NTP information with this option. Use the SNTP
information provided only if the NTP option is not present.
Update the test case as SNTP information is also requested.
Support DHCPv6 DNS search list option as specified in RFC 3646. This
option contains a list of DNS search domains encoded without compression
as specified in Section 8. of RFC 3315.
Revise the address iteration functions so that one helper function
resets the iterator to the start of the address list while the
second one fetches addresses one by one.
The test case is also updated.
Suppyling a NULL lease is not a condition that needs to be asserted,
returning -EINVAL is informative enough to the caller. This simplifies
calling code and doesn't falsely indicate that something erroneous was
attempted.
With this change the DHCP6_OPTION_IAADDR_LEN define can be removed in
favor of using sizeof(). Using the name of the struct and sizeof()
makes it clearer how much and what data is being copied from the
DHCPv6 message.
Add a Rapid Commit option to Solicit messages and expect a Reply to
be received instead of an Advertise. When receiving a DHCPv6 message
from the server in state Solicit, continue testing whether the
message is a Reply. Ease up the message type checking, it's not fatal
if the message is of a wrong type.
Add helper functions to set/get the rapid commit of a lease. See
RFC 3315, sections 17., 17.1.2., 17.1.4. and 18.1.8.
Create a helper function to compute the remaining time in seconds from
time T2 to the IPv6 address with the longest lifetime. The computed
time is used as the Maximum Retransmission Duration in Rebinding state.
See RFC 3315, section 18.1.4. for details.
Create a structure describing a DHCPv6 lease. Add internal functions
for creating a new lease and accessing the server ID, preference and
IAID. Provide functions for clearing addresses and associated timers.
External users are initially given only the capabilities of
referencing and unreferencing the lease structure.
Zbigniew Jędrzejewski-Szmek