This allows userspace to fake kdbus creds via struct ucred in the proxy,
without making the recieving side choke on the missing fields of the
kdbus struct, more precisel pid_starttime and tid
Previously we invalidated the peeked signature as soon as the caller
would recurse into a container, making stack based handling difficult.
With this change we will keep the peeked signature around until the user
advances to the next field.
Let's try to standardize on a single non-cryptographic hash algorithm,
and for that SipHash appears to be the best answer.
With this change there are two other hash functions left in systemd: an
older version of MurmurHash embedded into libudev for the bloom filters
in udev messages (which is hard to update, given that the we probably
should stay compatible with older versions of the library). And lookup3
in the journal files (which we could replace for new files, but which is
probably not worth the work).
Also, introduce a new environment variable named $WATCHDOG_PID which
cotnains the PID of the process that is supposed to send the keep-alive
events. This is similar how $LISTEN_FDS and $LISTEN_PID work together,
and protects against confusing processes further down the process tree
due to inherited environment.
Expiration of T1 timeout takes the client to the Rebinding state,
where it attempts to renew its lease. Start by opening a DCHP unicast
socket as there now is a proper IP address set.
Compute the resend timer as half of the remaining time down to a
minimum of 60 seconds (RFC2131). Modify DHCP Request sending to send
only UDP DHCP data when unicasting. Also modify DHCP Ack/Nak
receiving such that the client_receive_ack() takes care of using
either the full IP, UDP, DHCP packet or only the DHCP payload
depending whether the client is in Requesting or Renewing state.
Finally always report DHCP_EVENT_IP_ACQUIRE from Requesting state
and only DHCP_EVENT_IP_CHANGE if the IP address was modified when
the lease was renewed.
Create a helper functions setting up an unicast DHCP UDP socket and
sending data. Add function stubs for the test program.
[tomegun: initialize structs when allocating, and drop unneccesary 'err']
When a DHCP Nak is received, return a DHCP_EVENT_NO_LEASE event. If
some other DHCP message is received or an error happens when parsing
options, return -ENOMSG in order to ignore the packet. There may be
more than one server serving the same subnet, each server will send
its Offer to the client.