[3200] Respond with requested options only if lease has been assigned.

Conflicts:
	src/bin/dhcp4/dhcp4_srv.cc
	src/lib/dhcp/libdhcp++.cc

src/bin/dhcp4/dhcp4_srv.cc

@@ -754,13 +754,6 @@ Dhcpv4Srv::assignLease(const Pkt4Ptr& question, Pkt4Ptr& answer) {
         opt->setUint32(lease->valid_lft_);
         answer->addOption(opt);
 
-        // Router (type 3)
-        Subnet::OptionDescriptor opt_routers =
-            subnet->getOptionDescriptor("dhcp4", DHO_ROUTERS);
-        if (opt_routers.option) {
-            answer->addOption(opt_routers.option);
-        }
-
         // Subnet mask (type 1)
         answer->addOption(getNetmaskOption(subnet));
 
@@ -857,14 +850,17 @@ Dhcpv4Srv::processDiscover(Pkt4Ptr& discover) {
 
     copyDefaultFields(discover, offer);
     appendDefaultOptions(offer, DHCPOFFER);
-    appendRequestedOptions(discover, offer);
 
     assignLease(discover, offer);
 
-    // There are a few basic options that we always want to
-    // include in the response. If client did not request
-    // them we append them for him.
-    appendBasicOptions(discover, offer);
+    // Adding any other options makes sense only when we got the lease.
+    if (offer->getYiaddr() != IOAddress("0.0.0.0")) {
+        appendRequestedOptions(discover, offer);
+        // There are a few basic options that we always want to
+        // include in the response. If client did not request
+        // them we append them for him.
+        appendBasicOptions(discover, offer);
+    }
 
     return (offer);
 }
@@ -880,17 +876,20 @@ Dhcpv4Srv::processRequest(Pkt4Ptr& request) {
 
     copyDefaultFields(request, ack);
     appendDefaultOptions(ack, DHCPACK);
-    appendRequestedOptions(request, ack);
 
     // Note that we treat REQUEST message uniformly, regardless if this is a
     // first request (requesting for new address), renewing existing address
     // or even rebinding.
     assignLease(request, ack);
 
-    // There are a few basic options that we always want to
-    // include in the response. If client did not request
-    // them we append them for him.
-    appendBasicOptions(request, ack);
+    // Adding any other options makes sense only when we got the lease.
+    if (ack->getYiaddr() != IOAddress("0.0.0.0")) {
+        appendRequestedOptions(request, ack);
+        // There are a few basic options that we always want to
+        // include in the response. If client did not request
+        // them we append them for him.
+        appendBasicOptions(request, ack);
+    }
 
     return (ack);
 }

src/bin/dhcp4/tests/dhcp4_test_utils.cc

@@ -321,7 +321,7 @@ void Dhcpv4SrvTest::testDiscoverRequest(const uint8_t msg_type) {
     if (msg_type == DHCPDISCOVER) {
         ASSERT_NO_THROW(
             rsp = srv->processDiscover(req);
-            );
+        );
 
         // Should return OFFER
         ASSERT_TRUE(rsp);