GitLab

This was an obvious error and a trivial fix. Therefore it is being
committed on my discretion. It corrects build failures on some OSes
after merge of #4321.

If IA contains allocated lease for which there is a reservation
the liftime of this lease is extended. Any newly reserved
lease will be assigned to a different IA, possibly replacing
dynamically allocated lease.

This change triggered a lot of code refactoring for generating the
NameChangeRequests. Long story short is that the functions responsible
for generating NCRs from the lease information have been moved to
the libdhcpsrv where they better fit and where they may be used
by both allocation engine and the servers.

This change removes ability to disable allocation new leases new
Renew/Rebind, specified in RFC7550. The behavior specified in this
RFC is the only supported behavior.

Also added a few minor corrections to the DHCPv4 server and implemented
new Option6StatusCode.

Addressing more review comments...

new file - host_unittest.cc
    contains Dhcp6Client based host reservation tests

dhcp6_client.cc
dhcp6_client.h
    added setDuid(str) method to allow duid to be set to
    specific value

dhcp6_srv_unittest.cc -
    deleted host reservation tests, now in host_unittest.cc

dhcp6_test_utils.cc
dhcp6_test_utils.h
    deleted createHost6() method

src/bin/dhcp6/tests/dhcp6_srv_unittest.cc
    added tests:
    TEST_F(Dhcpv6SrvTest, hostReservationWithHostName)
    TEST_F(Dhcpv6SrvTest, hostReservationWithoutHostName)

src/bin/dhcp6/tests/dhcp6_test_utils.h
src/bin/dhcp6/tests/dhcp6_test_utils.cc
    Dhcpv6SrvTest::createHost6() - this method was moved
    here from FqdnDhcpv6SrvTest()

src/bin/dhcp6/tests/fqdn_unittest.cc
    added tests:
    TEST_F(FqdnDhcpv6SrvTest, hostnameReservationSuffix)
    TEST_F(FqdnDhcpv6SrvTest, hostnameReservationNoSuffix)
    TEST_F(FqdnDhcpv6SrvTest, hostnameReservationDdnsDisabled)