[3628] Addressed review comments.

One of the major changes was to eliminate possibility of defining the dead
reservation: neither hostname nor IP address reserved and covering it with
suitable unit tests.

1 files changed, 22 insertions, 3 deletions

diff --git a/src/lib/dhcpsrv/cfg_hosts.cc b/src/lib/dhcpsrv/cfg_hosts.cc
index 7e8bcbc405..7b503df74a 100644
--- a/src/lib/dhcpsrv/cfg_hosts.cc
+++ b/src/lib/dhcpsrv/cfg_hosts.cc
@@ -14,6 +14,7 @@
 
 #include <dhcpsrv/cfg_hosts.h>
 #include <exceptions/exceptions.h>
+#include <ostream>
 
 using namespace isc::asiolink;
 
@@ -165,10 +166,26 @@ CfgHosts::add(const HostPtr& host) {
         isc_throw(BadValue, "specified host object must not be NULL when it"
                   " is added to the configuration");
     }
-    /// @todo This may need further sanity checks. For example, a duplicate
-    /// should be rejected.
+
     HWAddrPtr hwaddr = host->getHWAddress();
     DuidPtr duid = host->getDuid();
+
+    // There should be at least one resource reserved: hostname, IPv4
+    // address, IPv6 address or prefix.
+    if (host->getHostname().empty() &&
+        (host->getIPv4Reservation() == IOAddress("0.0.0.0")) &&
+        (!host->hasIPv6Reservation())) {
+        std::ostringstream s;
+        if (hwaddr) {
+            s << "for DUID: " << hwaddr->toText();
+        } else if (duid) {
+            s << "for HW address: " << duid->toText();
+        }
+        isc_throw(BadValue, "specified reservation " << s
+                  << " must include at least one resource, i.e. "
+                  "hostname, IPv4 address or IPv6 address/prefix");
+    }
+
     // Check for duplicates for the specified IPv4 subnet.
     if (get4(host->getIPv4SubnetID(), hwaddr, duid)) {
         isc_throw(DuplicateHost, "failed to add new host using the HW"
@@ -177,7 +194,7 @@ CfgHosts::add(const HostPtr& host) {
                   << "' to the IPv4 subnet id '" << host->getIPv4SubnetID()
                   << "' as this host has already been added");
 
-    // Checek for duplicates for the specified IPv6 subnet.
+    // Check for duplicates for the specified IPv6 subnet.
     } else if (get6(host->getIPv6SubnetID(), duid, hwaddr)) {
         isc_throw(DuplicateHost, "failed to add new host using the HW"
                   " address '" << (hwaddr ? hwaddr->toText(false) : "(null)")
@@ -186,6 +203,8 @@ CfgHosts::add(const HostPtr& host) {
                   << "' as this host has already been added");
     }
 
+    /// @todo This may need further sanity checks.
+
     // This is a new instance - add it.
     hosts_.insert(host);
 }