[3035] Basic implementation of the function which computes DHCID.

src/bin/dhcp4/Makefile.am

@@ -56,6 +56,7 @@ nodist_b10_dhcp4_SOURCES = dhcp4_messages.h dhcp4_messages.cc
 EXTRA_DIST += dhcp4_messages.mes
 
 b10_dhcp4_LDADD  = $(top_builddir)/src/lib/dhcp/libb10-dhcp++.la
+b10_dhcp4_LDADD += $(top_builddir)/src/lib/dhcp_ddns/libb10-dhcp_ddns.la
 b10_dhcp4_LDADD += $(top_builddir)/src/lib/util/libb10-util.la
 b10_dhcp4_LDADD += $(top_builddir)/src/lib/dhcpsrv/libb10-dhcpsrv.la
 b10_dhcp4_LDADD += $(top_builddir)/src/lib/exceptions/libb10-exceptions.la

src/bin/dhcp4/dhcp4_srv.cc

@@ -43,6 +43,7 @@
 using namespace isc;
 using namespace isc::asiolink;
 using namespace isc::dhcp;
+using namespace isc::dhcp_ddns;
 using namespace isc::hooks;
 using namespace isc::log;
 using namespace std;
@@ -568,6 +569,47 @@ Dhcpv4Srv::srvidToString(const OptionPtr& srvid) {
     return (addrs[0].toText());
 }
 
+isc::dhcp_ddns::D2Dhcid
+Dhcpv4Srv::computeDhcid(const Pkt4Ptr& query, const Pkt4Ptr& answer) {
+    std::vector<uint8_t> dhcid_data(1);
+    OptionPtr client_id = answer->getOption(DHO_DHCP_CLIENT_IDENTIFIER);
+    if (client_id) {
+        dhcid_data.push_back(1);
+        dhcid_data.insert(dhcid_data.end(), client_id->getData().begin(),
+                          client_id->getData().end());
+    } else {
+        HWAddrPtr hwaddr = query->getHWAddr();
+        dhcid_data.push_back(0);
+        dhcid_data.push_back(hwaddr->htype_);
+        dhcid_data.insert(dhcid_data.end(), hwaddr->hwaddr_.begin(),
+                          hwaddr->hwaddr_.end());
+    }
+
+    std::string domain_name;
+    Option4ClientFqdnPtr fqdn = boost::dynamic_pointer_cast<Option4ClientFqdn>
+        (answer->getOption(DHO_FQDN));
+    if (fqdn) {
+        domain_name = fqdn->getDomainName();
+
+    } else {
+        OptionCustomPtr hostname = boost::dynamic_pointer_cast<OptionCustom>
+            (answer->getOption(DHO_HOST_NAME));
+        if (hostname) {
+            domain_name = hostname->readString();
+        }
+
+    }
+    try {
+        OptionDataTypeUtil::writeFqdn(domain_name, dhcid_data, true);
+    } catch (const Exception& ex) {
+        ;
+    }
+
+    D2Dhcid dhcid(dhcid_data);
+    return (dhcid);
+
+}
+
 void
 Dhcpv4Srv::copyDefaultFields(const Pkt4Ptr& question, Pkt4Ptr& answer) {
     answer->setIface(question->getIface());

src/bin/dhcp4/dhcp4_srv.h

@@ -19,6 +19,7 @@
 #include <dhcp/pkt4.h>
 #include <dhcp/option.h>
 #include <dhcp/option4_client_fqdn.h>
+#include <dhcp_ddns/ncr_msg.h>
 #include <dhcpsrv/subnet.h>
 #include <dhcpsrv/alloc_engine.h>
 #include <hooks/callout_handle.h>
@@ -376,6 +377,16 @@ protected:
     /// @return string representation
     static std::string srvidToString(const OptionPtr& opt);
 
+    /// @brief Computes DHCID using options stored in the response message
+    /// to a client.
+    ///
+    /// @param query An object encapsulating client's message to the server.
+    /// @param answer An object encapsulating response message being sent to
+    /// a client.
+    /// @return An object encapsulating DHCID to be used for DNS updates.
+    static isc::dhcp_ddns::D2Dhcid computeDhcid(const Pkt4Ptr& query,
+                                                const Pkt4Ptr& answer);
+
     /// @brief Selects a subnet for a given client's packet.
     ///
     /// @param question client's message

src/bin/dhcp4/tests/Makefile.am

@@ -82,6 +82,7 @@ dhcp4_unittests_LDADD += $(top_builddir)/src/lib/asiolink/libb10-asiolink.la
 dhcp4_unittests_LDADD += $(top_builddir)/src/lib/cc/libb10-cc.la
 dhcp4_unittests_LDADD += $(top_builddir)/src/lib/config/libb10-cfgclient.la
 dhcp4_unittests_LDADD += $(top_builddir)/src/lib/dhcp/libb10-dhcp++.la
+dhcp4_unittests_LDADD += $(top_builddir)/src/lib/dhcp_ddns/libb10-dhcp_ddns.la
 dhcp4_unittests_LDADD += $(top_builddir)/src/lib/dhcpsrv/libb10-dhcpsrv.la
 dhcp4_unittests_LDADD += $(top_builddir)/src/lib/exceptions/libb10-exceptions.la
 dhcp4_unittests_LDADD += $(top_builddir)/src/lib/log/libb10-log.la