[3034] Updated Dhcpv6Srv to use D2ClientMgr fqdn methods

Replaced constants and logic in Dhcp6Srv::processClientFqdn()
with use of D2ClientMgr configuration-sensitive FQDN flag
and domain name methods.

src/bin/dhcp6/dhcp6_srv.cc

@@ -104,13 +104,8 @@ namespace {
 // DHCPv6 Client FQDN Option sent by a client. They will be removed
 // when DDNS parameters for DHCPv6 are implemented with the ticket #3034.
 
-// Enable AAAA RR update delegation to the client (Disabled).
-const bool FQDN_ALLOW_CLIENT_UPDATE = false;
 // Globally enable updates (Enabled).
 const bool FQDN_ENABLE_UPDATE = true;
-// The partial name generated for the client if empty name has been
-// supplied.
-const char* FQDN_GENERATED_PARTIAL_NAME = "myhost";
 // Do update, even if client requested no updates with N flag (Disabled).
 const bool FQDN_OVERRIDE_NO_UPDATE = false;
 // Server performs an update when client requested delegation (Enabled).
@@ -1012,69 +1007,18 @@ Dhcpv6Srv::processClientFqdn(const Pkt6Ptr& question, const Pkt6Ptr& answer) {
 
     LOG_DEBUG(dhcp6_logger, DBG_DHCP6_DETAIL,
               DHCP6_DDNS_RECEIVE_FQDN).arg(fqdn->toText());
-
-
-    // Prepare the FQDN option which will be included in the response to
-    // the client.
+    // Create the DHCPv6 Client FQDN Option to be included in the server's
+    // response to a client.
     Option6ClientFqdnPtr fqdn_resp(new Option6ClientFqdn(*fqdn));
-    // RFC 4704, section 6. - all flags set to 0.
-    fqdn_resp->resetFlags();
-
-    // Conditions when N flag has to be set to indicate that server will not
-    // perform DNS updates:
-    // 1. Updates are globally disabled,
-    // 2. Client requested no update and server respects it,
-    // 3. Client requested that the AAAA update is delegated to the client but
-    //    server neither respects delegation of updates nor it is configured
-    //    to send update on its own when client requested delegation.
-    if (!FQDN_ENABLE_UPDATE ||
-        (fqdn->getFlag(Option6ClientFqdn::FLAG_N) &&
-         !FQDN_OVERRIDE_NO_UPDATE) ||
-        (!fqdn->getFlag(Option6ClientFqdn::FLAG_S) &&
-         !FQDN_ALLOW_CLIENT_UPDATE && !FQDN_OVERRIDE_CLIENT_UPDATE)) {
-        fqdn_resp->setFlag(Option6ClientFqdn::FLAG_N, true);
-
-    // Conditions when S flag is set to indicate that server will perform
-    // DNS update on its own:
-    // 1. Client requested that server performs DNS update and DNS updates are
-    //    globally enabled
-    // 2. Client requested that server delegates AAAA update to the client but
-    //    server doesn't respect delegation and it is configured to perform
-    //    an update on its own when client requested delegation.
-    } else if (fqdn->getFlag(Option6ClientFqdn::FLAG_S) ||
-               (!fqdn->getFlag(Option6ClientFqdn::FLAG_S) &&
-                !FQDN_ALLOW_CLIENT_UPDATE && FQDN_OVERRIDE_CLIENT_UPDATE)) {
-        fqdn_resp->setFlag(Option6ClientFqdn::FLAG_S, true);
-    }
-
-    // Server MUST set the O flag if it has overridden the client's setting
-    // of S flag.
-    if (fqdn->getFlag(Option6ClientFqdn::FLAG_S) !=
-        fqdn_resp->getFlag(Option6ClientFqdn::FLAG_S)) {
-        fqdn_resp->setFlag(Option6ClientFqdn::FLAG_O, true);
-    }
-
-    // If client supplied partial or empty domain-name, server should
-    // generate one.
-    if (fqdn->getDomainNameType() == Option6ClientFqdn::PARTIAL) {
-        std::ostringstream name;
-        if (fqdn->getDomainName().empty() || FQDN_REPLACE_CLIENT_NAME) {
-            fqdn->setDomainName("", Option6ClientFqdn::PARTIAL);
-
-        } else {
-            name << fqdn->getDomainName();
-            name << "." << FQDN_PARTIAL_SUFFIX;
-            fqdn_resp->setDomainName(name.str(), Option6ClientFqdn::FULL);
-        }
 
-    // Server may be configured to replace a name supplied by a client,
-    // even if client supplied fully qualified domain-name.
-    } else if (FQDN_REPLACE_CLIENT_NAME) {
-        std::ostringstream name;
-        name << FQDN_GENERATED_PARTIAL_NAME << "." << FQDN_PARTIAL_SUFFIX;
-        fqdn_resp->setDomainName(name.str(), Option6ClientFqdn::FULL);
+    // Set the server S, N, and O flags based on client's flags and
+    // current configuration.
+    D2ClientMgr& d2_mgr = CfgMgr::instance().getD2ClientMgr();
+    d2_mgr.adjustFqdnFlags<Option6ClientFqdn>(*fqdn, *fqdn_resp);
 
-    }
+    // Adjust the domain name based on domain name value and type sent by the
+    // client and current configuration.
+    d2_mgr.adjustDomainName<Option6ClientFqdn>(*fqdn, *fqdn_resp);
 
     // The FQDN has been processed successfully. Let's append it to the
     // response to be sent to a client. Note that the Client FQDN option is
@@ -1295,14 +1239,11 @@ Dhcpv6Srv::assignIA_NA(const Subnet6Ptr& subnet, const DuidPtr& duid,
     Option6ClientFqdnPtr fqdn = boost::dynamic_pointer_cast<
         Option6ClientFqdn>(answer->getOption(D6O_CLIENT_FQDN));
     if (fqdn) {
-        // Flag S must not coexist with flag N being set to 1, so if S=1
-        // server takes responsibility for both reverse and forward updates.
-        // Otherwise, we have to check N.
+        // For now, we assert that if we are doing forward we are also
+        // doing reverse.
         if (fqdn->getFlag(Option6ClientFqdn::FLAG_S)) {
             do_fwd = true;
             do_rev = true;
-        } else if (!fqdn->getFlag(Option6ClientFqdn::FLAG_N)) {
-            do_rev = true;
         }
     }
     // Set hostname only in case any of the updates is being performed.
@@ -1553,11 +1494,11 @@ Dhcpv6Srv::renewIA_NA(const Subnet6Ptr& subnet, const DuidPtr& duid,
     Option6ClientFqdnPtr fqdn = boost::dynamic_pointer_cast<
         Option6ClientFqdn>(answer->getOption(D6O_CLIENT_FQDN));
     if (fqdn) {
+        // For now, we assert that if we are doing forward we are also
+        // doing reverse.
         if (fqdn->getFlag(Option6ClientFqdn::FLAG_S)) {
             do_fwd = true;
             do_rev = true;
-        } else if (!fqdn->getFlag(Option6ClientFqdn::FLAG_N)) {
-            do_rev = true;
         }
     }
 

src/bin/dhcp6/tests/fqdn_unittest.cc

@@ -43,20 +43,62 @@ namespace {
 /// @brief A test fixture class for testing DHCPv6 Client FQDN Option handling.
 class FqdnDhcpv6SrvTest : public Dhcpv6SrvTest {
 public:
+    // Reference to D2ClientMgr singleton
+    D2ClientMgr& d2_mgr_;
+
+    // Bit Constants for turning on and off DDNS configuration options.
+    static const uint16_t ALWAYS_INCLUDE_FQDN = 1;
+    static const uint16_t OVERRIDE_NO_UPDATE = 2;
+    static const uint16_t OVERRIDE_CLIENT_UPDATE = 4;
+    static const uint16_t REPLACE_CLIENT_NAME = 8;
 
     /// @brief Constructor
     FqdnDhcpv6SrvTest()
-        : Dhcpv6SrvTest() {
+        : Dhcpv6SrvTest(), d2_mgr_(CfgMgr::instance().getD2ClientMgr()) {
         // generateClientId assigns DUID to duid_.
         generateClientId();
         lease_.reset(new Lease6(Lease::TYPE_NA, IOAddress("2001:db8:1::1"),
                                 duid_, 1234, 501, 502, 503,
                                 504, 1, 0));
-
+        // Config DDNS to be enabled, all controls off
+        enableD2();
     }
 
     /// @brief Destructor
     virtual ~FqdnDhcpv6SrvTest() {
+        // Default constructor creates a config with DHCP-DDNS updates
+        // disabled.
+        D2ClientConfigPtr cfg(new D2ClientConfig());
+        CfgMgr::instance().setD2ClientConfig(cfg);
+    }
+
+    /// @brief Sets the server's DDNS configuration to ddns updates disabled.
+    void disableD2() {
+        // Default constructor creates a config with DHCP-DDNS updates
+        // disabled.
+        D2ClientConfigPtr cfg(new D2ClientConfig());
+        CfgMgr::instance().setD2ClientConfig(cfg);
+    }
+
+    /// @brief Enables DHCP-DDNS updates with the given options enabled.
+    ///
+    /// Replaces the current D2ClientConfiguration with a configuration
+    /// which as updates enabled and the control options set based upon
+    /// the bit mask of options.
+    ///
+    /// @param mask Bit mask of configuration options that should be enabled.
+    void enableD2(const uint16_t mask = 0) {
+        D2ClientConfigPtr cfg;
+
+        ASSERT_NO_THROW(cfg.reset(new D2ClientConfig(true,
+                                  isc::asiolink::IOAddress("127.0.0.1"), 53001,
+                                  dhcp_ddns::NCR_UDP, dhcp_ddns::FMT_JSON,
+                                  (mask & ALWAYS_INCLUDE_FQDN),
+                                  (mask & OVERRIDE_NO_UPDATE),
+                                  (mask & OVERRIDE_CLIENT_UPDATE),
+                                  (mask & REPLACE_CLIENT_NAME),
+                                  "myhost", "example.com")));
+        ASSERT_NO_THROW(CfgMgr::instance().setD2ClientConfig(cfg));
     }
 
     /// @brief Construct the DHCPv6 Client FQDN option using flags and
@@ -443,6 +485,7 @@ TEST_F(FqdnDhcpv6SrvTest, noUpdate) {
 // Test server's response when client requests that server delegates the AAAA
 // update to the client and this delegation is not allowed.
 TEST_F(FqdnDhcpv6SrvTest, clientAAAAUpdateNotAllowed) {
+    enableD2(OVERRIDE_CLIENT_UPDATE);
     testFqdn(DHCPV6_SOLICIT, 0, "myhost.example.com.",
              Option6ClientFqdn::FULL,
              Option6ClientFqdn::FLAG_S | Option6ClientFqdn::FLAG_O,