1 files changed, 149 insertions, 0 deletions
diff --git a/src/hooks/dhcp/user_chk/pkt_receive_co.cc b/src/hooks/dhcp/user_chk/pkt_receive_co.cc
new file mode 100644
index 0000000..1fb659b
--- /dev/null
+++ b/src/hooks/dhcp/user_chk/pkt_receive_co.cc
@@ -0,0 +1,149 @@
+// Copyright (C) 2013-2020 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+/// @file pkt_receive_co.cc Defines the pkt4_receive and pkt6_receive callout functions.
+
+#include <config.h>
+#include <hooks/hooks.h>
+#include <dhcp/pkt4.h>
+#include <dhcp/dhcp6.h>
+#include <dhcp/pkt6.h>
+#include <user_chk.h>
+
+using namespace isc::dhcp;
+using namespace isc::hooks;
+using namespace user_chk;
+using namespace std;
+
+// Functions accessed by the hooks framework use C linkage to avoid the name
+// mangling that accompanies use of the C++ compiler as well as to avoid
+// issues related to namespaces.
+extern "C" {
+
+/// @brief  This callout is called at the "pkt4_receive" hook.
+///
+/// This function determines if the DHCP client identified by the inbound
+/// DHCP query packet is in the user registry.
+/// Upon entry, the registry is refreshed. Next the hardware address is
+/// extracted from query and saved to the context as the "query_user_id".
+/// This id is then used to search the user registry.  The resultant UserPtr
+/// whether the user is found or not, is saved to the callout context as
+/// "registered_user".   This makes the registered user, if not null, available
+/// to subsequent callouts.
+///
+/// @param handle CalloutHandle which provides access to context.
+///
+/// @return 0 upon success, non-zero otherwise.
+int pkt4_receive(CalloutHandle& handle) {
+    CalloutHandle::CalloutNextStep status = handle.getStatus();
+    if (status == CalloutHandle::NEXT_STEP_DROP ||
+        status == CalloutHandle::NEXT_STEP_SKIP) {
+        return (0);
+    }
+
+    if (!user_registry) {
+        std::cout << "DHCP UserCheckHook : pkt4_receive UserRegistry is null"
+                  << std::endl;
+        return (1);
+    }
+
+    try {
+        // Refresh the registry.
+        user_registry->refresh();
+
+        // Get the HWAddress to use as the user identifier.
+        Pkt4Ptr query;
+        handle.getArgument("query4", query);
+        HWAddrPtr hwaddr = query->getHWAddr();
+
+        // Store the id we search with so it is available down the road.
+        handle.setContext(query_user_id_label, hwaddr);
+
+        // Look for the user in the registry.
+        UserPtr registered_user = user_registry->findUser(*hwaddr);
+
+        // Store user regardless. Empty user pointer means non-found. It is
+        // cheaper to fetch it and test it, than to use an exception throw.
+        handle.setContext(registered_user_label, registered_user);
+        std::cout << "DHCP UserCheckHook : pkt4_receive user : "
+                  << hwaddr->toText() << " is "
+                  << (registered_user ? " registered" : " not registered")
+                  << std::endl;
+    } catch (const std::exception& ex) {
+        std::cout << "DHCP UserCheckHook : pkt4_receive unexpected error: "
+                  << ex.what() << std::endl;
+        return (1);
+    }
+
+    return (0);
+}
+
+/// @brief  This callout is called at the "pkt6_receive" hook.
+///
+/// This function determines if the DHCP client identified by the inbound
+/// DHCP query packet is in the user registry.
+/// Upon entry, the registry is refreshed. Next the DUID is extracted from
+/// query and saved to the context as the "query_user_id". This id is then
+/// used to search the user registry.  The resultant UserPtr whether the user
+/// is found or not, is saved to the callout context as "registered_user".
+/// This makes the registered user, if not null, available to subsequent
+/// callouts.
+///
+/// @param handle CalloutHandle which provides access to context.
+///
+/// @return 0 upon success, non-zero otherwise.
+int pkt6_receive(CalloutHandle& handle) {
+    CalloutHandle::CalloutNextStep status = handle.getStatus();
+    if (status == CalloutHandle::NEXT_STEP_DROP ||
+        status == CalloutHandle::NEXT_STEP_SKIP) {
+        return (0);
+    }
+
+    if (!user_registry) {
+        std::cout << "DHCP UserCheckHook : pkt6_receive UserRegistry is null"
+                  << std::endl;
+        return (1);
+    }
+
+    try {
+        // Refresh the registry.
+        user_registry->refresh();
+
+        // Fetch the inbound packet.
+        Pkt6Ptr query;
+        handle.getArgument("query6", query);
+
+        // Get the DUID to use as the user identifier.
+        OptionPtr opt_duid = query->getOption(D6O_CLIENTID);
+        if (!opt_duid) {
+            std::cout << "DHCP6 query is missing DUID" << std::endl;
+            return (1);
+        }
+        DuidPtr duid = DuidPtr(new DUID(opt_duid->getData()));
+
+        // Store the id we search with so it is available down the road.
+        handle.setContext(query_user_id_label, duid);
+
+        // Look for the user in the registry.
+        UserPtr registered_user = user_registry->findUser(*duid);
+
+        // Store user regardless. Empty user pointer means non-found. It is
+        // cheaper to fetch it and test it, than to use an exception throw.
+        handle.setContext(registered_user_label, registered_user);
+        std::cout << "DHCP UserCheckHook : pkt6_receive user : "
+                  << duid->toText() << " is "
+                  << (registered_user ? " registered" : " not registered")
+                  << std::endl;
+    } catch (const std::exception& ex) {
+        std::cout << "DHCP UserCheckHook : pkt6_receive unexpected error: "
+                  << ex.what() << std::endl;
+        return (1);
+    }
+
+    return (0);
+}
+
+} // end extern "C"