[#3683] Checkpoint: created dedicated UT file

src/bin/dhcp6/tests/Makefile.am

@@ -87,6 +87,7 @@ PROGRAM_TESTS = dhcp6_unittests
 # This list is ordered alphabetically. When adding new files, please maintain
 # this order.
 dhcp6_unittests_SOURCES  =
+dhcp6_unittests_SOURCES += addr_reg_unittest.cc
 dhcp6_unittests_SOURCES += classify_unittest.cc
 dhcp6_unittests_SOURCES += client_handler_unittest.cc
 dhcp6_unittests_SOURCES += config_parser_unittest.cc

src/bin/dhcp6/tests/addr_reg_unittest.cc

@@ -0,0 +1,410 @@
+// Copyright (C) 2025 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/.
+
+#include <config.h>
+#include <asiolink/io_address.h>
+#include <cc/data.h>
+#include <dhcp/testutils/iface_mgr_test_config.h>
+#include <dhcp6/json_config_parser.h>
+#include <dhcp6/tests/dhcp6_message_test.h>
+#include <dhcpsrv/utils.h>
+
+using namespace isc;
+using namespace isc::asiolink;
+using namespace isc::data;
+using namespace isc::dhcp;
+using namespace isc::dhcp::test;
+using namespace std;
+
+namespace {
+
+/// @brief Test fixture class for testing address registration..
+class AddrRegTest : public Dhcpv6MessageTest {
+public:
+
+    /// @brief Constructor.
+    ///
+    /// Sets up fake interfaces.
+    AddrRegTest() : Dhcpv6MessageTest() {
+    }
+
+    /// @brief Generate IAADDR option with specified parameters.
+    ///
+    /// @param addr The address.
+    /// @param preferred_lft The preferred lifetime.
+    /// @param valid_lft The valid lifetime.
+    Option6IAAddrPtr generateIAAddr(const IOAddress& addr,
+                                    uint32_t preferred_lft,
+                                    uint32_t valid_lft) {
+        Option6IAAddrPtr iaaddr(new Option6IAAddr(D6O_IAADDR, addr,
+                                                  preferred_lft, valid_lft));
+        return (iaaddr);
+    }
+
+    /// @brief Generate IAADDR option with specified parameters.
+    ///
+    /// @param addr The address in textual form.
+    /// @param preferred_lft The preferred lifetime.
+    /// @param valid_lft The valid lifetime.
+    Option6IAAddrPtr generateIAAddr(const string& addr,
+                                    uint32_t preferred_lft,
+                                    uint32_t valid_lft) {
+        return (generateIAAddr(IOAddress(addr), preferred_lft, valid_lft));
+    }
+
+    /// @brief Basic configuration.
+    string config_ = "{\n"
+        "\"interfaces-config\": { \"interfaces\": [ \"*\" ] },\n"
+        "\"valid-lifetime\": 4000,\n"
+        "\"preferred-lifetime\": 3000,\n"
+        "\"rebind-timer\": 2000,\n"
+        "\"renew-timer\": 1000,\n"
+        "\"subnet6\": [ {\n"
+        "    \"id\": 1,\n"
+        "    \"subnet\": \"2001:db8:1::/64\",\n"
+        "    \"interface\": \"eth0\"\n"
+        "} ]\n"
+        "}\n";
+};
+
+// Test that client-id is mandatory and server-id forbidden for
+// Addr-reg-inform messages
+TEST_F(AddrRegTest, sanityCheck) {
+    // A message with no client-id should fail
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    EXPECT_FALSE(srv_.sanityCheck(addr_reg_inf));
+
+    // A message with a single client-id should succeed
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    EXPECT_TRUE(srv_.sanityCheck(addr_reg_inf));
+
+    // A message with server-id present should fail
+    addr_reg_inf->addOption(srv_.getServerID());
+    EXPECT_FALSE(srv_.sanityCheck(addr_reg_inf));
+}
+
+// Test that subnet selection must return a subnet for processAddrRegInform.
+TEST_F(AddrRegTest, noSubnet) {
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_FALSE(ctx.subnet_);
+
+    // No server: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    // The query is silently rejected so no log to check.
+}
+
+// Test that an IA_NA option is required.
+TEST_F(AddrRegTest, noIA_NA) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // No IA_NA: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client fe80::abcd: ";
+    expected += "Exactly 1 IA_NA option expected, but 0 received";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+// Test that exactly one IA_NA option is required.
+TEST_F(AddrRegTest, twoIA_NAs) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    addr_reg_inf->addOption(generateIA(D6O_IA_NA, 234, 1500, 3000));
+    addr_reg_inf->addOption(generateIA(D6O_IA_NA, 345, 1500, 3000));
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // 2 IA_NA options: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client fe80::abcd: ";
+    expected += "Exactly 1 IA_NA option expected, but 2 received";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+// Test that an IA_NA sub-option is required.
+TEST_F(AddrRegTest, noIA_NAsub) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    addr_reg_inf->addOption(generateIA(D6O_IA_NA, 234, 1500, 3000));
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // No IA_NA sub-options: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client fe80::abcd: ";
+    expected += "Exactly 1 IA_NA sub-option expected, but 0 received";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+// Test that an exactly one IA_NA sub-option is required.
+TEST_F(AddrRegTest, twoIA_NAsub) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    auto ia = generateIA(D6O_IA_NA, 234, 1500, 3000);
+    ia->addOption(generateIAAddr("2001:db8:1::1", 3000, 4000));
+    ia->addOption(generateIAAddr("2001:db8:1::2", 3000, 4000));
+    addr_reg_inf->addOption(ia);
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // Two IA_NA sub-options: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client fe80::abcd: ";
+    expected += "Exactly 1 IA_NA sub-option expected, but 2 received";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+// Test that addresses must match.
+TEST_F(AddrRegTest, noAddrMatch) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    auto ia = generateIA(D6O_IA_NA, 234, 1500, 3000);
+    ia->addOption(generateIAAddr("2001:db8:1::1", 3000, 4000));
+    addr_reg_inf->addOption(ia);
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // Address mismatch: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client fe80::abcd: ";
+    expected += "Address mismatch: client at fe80::abcd ";
+    expected += "wants to register 2001:db8:1::1";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+// Test that addresses must match with a relay.
+TEST_F(AddrRegTest, noAddrMatchRelay) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    auto ia = generateIA(D6O_IA_NA, 234, 1500, 3000);
+    ia->addOption(generateIAAddr("2001:db8:1::1", 3000, 4000));
+    addr_reg_inf->addOption(ia);
+
+    // Add a relay.
+    Pkt6::RelayInfo relay;
+    relay.linkaddr_ = IOAddress("fe80::ef01");
+    relay.peeraddr_ = IOAddress("fe80::1");
+    addr_reg_inf->relay_info_.push_back(relay);
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // Address mismatch: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client fe80::ef01: ";
+    expected += "Address mismatch: client at fe80::ef01 ";
+    expected += "wants to register 2001:db8:1::1";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+// Test that addresses must match with relays.
+TEST_F(AddrRegTest, noAddrMatch2Relays) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("fe80::abcd"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    auto ia = generateIA(D6O_IA_NA, 234, 1500, 3000);
+    ia->addOption(generateIAAddr("2001:db8:1::1", 3000, 4000));
+    addr_reg_inf->addOption(ia);
+
+    // Add a relay: it will be the outer one.
+    Pkt6::RelayInfo relay;
+    relay.linkaddr_ = IOAddress("fe80::ef01");
+    relay.peeraddr_ = IOAddress("fe80::1");
+    addr_reg_inf->relay_info_.push_back(relay);
+
+    // Add a second relay: it will be the inner one.
+    Pkt6::RelayInfo relay2;
+    relay2.linkaddr_ = IOAddress("fe80::2345");
+    relay2.peeraddr_ = IOAddress("fe80::1");
+    addr_reg_inf->relay_info_.push_back(relay2);
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // Address mismatch: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client fe80::2345: ";
+    expected += "Address mismatch: client at fe80::2345 ";
+    expected += "wants to register 2001:db8:1::1";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+// Test that the registering address must be in the subnet.
+TEST_F(AddrRegTest, noInSubnet) {
+    IfaceMgrTestConfig test_config(true);
+
+    ASSERT_NO_THROW(configure(config_));
+
+    Pkt6Ptr addr_reg_inf = Pkt6Ptr(new Pkt6(DHCPV6_ADDR_REG_INFORM, 1234));
+    addr_reg_inf->setRemoteAddr(IOAddress("2001:db8::1"));
+    addr_reg_inf->setIface("eth0");
+    addr_reg_inf->setIndex(ETH0_INDEX);
+    OptionPtr clientid = generateClientId();
+    addr_reg_inf->addOption(clientid);
+    auto ia = generateIA(D6O_IA_NA, 234, 1500, 3000);
+    ia->addOption(generateIAAddr("2001:db8::1", 3000, 4000));
+    addr_reg_inf->addOption(ia);
+
+    // Pass it to the server.
+    AllocEngine::ClientContext6 ctx;
+    bool drop = !srv_.earlyGHRLookup(addr_reg_inf, ctx);
+    ASSERT_FALSE(drop);
+    ctx.subnet_ = srv_.selectSubnet(addr_reg_inf, drop);
+    ASSERT_FALSE(drop);
+    srv_.initContext(ctx, drop);
+    ASSERT_FALSE(drop);
+    ASSERT_TRUE(ctx.subnet_);
+
+    // Not in subnet: no response.
+    EXPECT_FALSE(srv_.processAddrRegInform(ctx));
+
+    string expected = "DHCP6_ADDR_REG_INFORM_FAIL ";
+    expected += "error on addr-reg-inform from client 2001:db8::1: ";
+    expected += "Address 2001:db8::1 is not in subnet ";
+    expected += "2001:db8:1::/64 (id 1)";
+    EXPECT_EQ(1, countFile(expected));
+}
+
+} // end of anonymous namespace

src/bin/dhcp6/tests/ctrl_dhcp6_srv_unittest.cc

@@ -617,11 +617,14 @@ TEST_F(CtrlChannelDhcpv6SrvTest, controlChannelStats) {
         "pkt6-infrequest-received",
         "pkt6-dhcpv4-query-received",
         "pkt6-dhcpv4-response-received",
+        "pkt6-addr-reg-inform-received",
+        "pkt6-addr-reg-reply-received",
         "pkt6-unknown-received",
         "pkt6-sent",
         "pkt6-advertise-sent",
         "pkt6-reply-sent",
         "pkt6-dhcpv4-response-sent",
+        "pkt6-addr-reg-reply-sent",
         "pkt6-parse-failed",
         "pkt6-receive-drop",
         "v6-allocation-fail",

src/bin/dhcp6/tests/dhcp6_client.cc

@@ -1,4 +1,4 @@
-// Copyright (C) 2014-2024 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2014-2025 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
@@ -608,6 +608,20 @@ Dhcp6Client::doRelease() {
     }
 }
 
+void
+Dhcp6Client::doAddrRegInform() {
+    context_.query_ = createMsg(DHCPV6_ADDR_REG_INFORM);
+
+    // Append requested IAs.
+    appendRequestedIAs(context_.query_);
+
+    // Add Client FQDN if configured.
+    appendFQDN();
+
+    sendMsg(context_.query_);
+    context_.response_ = receiveOneMsg();
+}
+
 void
 Dhcp6Client::generateIAFromLeases(const Pkt6Ptr& query,
                                   const bool include_address) {

src/bin/dhcp6/tests/dhcp6_client.h

@@ -1,4 +1,4 @@
-// Copyright (C) 2014-2020 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2014-2025 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
@@ -311,6 +311,12 @@ public:
     /// and receiving server's response.
     void doRelease();
 
+    /// @brief This function generates Addr-reg-inform message, sends it
+    /// to the server and then receives the Addr-reg-reply.
+    /// This method does not process the response in any specific way,
+    /// just stores it.
+    void doAddrRegInform();
+
     /// @brief Removes the stateful configuration obtained from the server.
     ///
     /// It removes all leases held by the client.

src/bin/dhcp6/tests/dhcp6_srv_unittest.cc

@@ -3640,6 +3640,11 @@ TEST_F(Dhcpv6SrvTest, receiveDhcpv4QueryStat) {
     testReceiveStats(DHCPV6_DHCPV4_QUERY, "pkt6-dhcpv4-query-received");
 }
 
+// Test checks if pkt6-addr-reg-inform-received is bumped up correctly.
+TEST_F(Dhcpv6SrvTest, receiveAddrRegInformStat) {
+    testReceiveStats(DHCPV6_ADDR_REG_INFORM, "pkt6-addr-reg-inform-received");
+}
+
 // Test checks if reception of a malformed packet increases pkt-parse-failed
 // and pkt6-receive-drop
 TEST_F(Dhcpv6SrvTest, receiveParseFailedStat) {

src/bin/dhcp6/tests/dhcp6_test_utils.cc

@@ -1,4 +1,4 @@
-// Copyright (C) 2013-2024 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2013-2025 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

src/bin/dhcp6/tests/dhcp6_test_utils.h

@@ -1,4 +1,4 @@
-// Copyright (C) 2013-2024 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2013-2025 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
@@ -345,6 +345,27 @@ public:
         return (processDecline(ctx));
     }
 
+    /// @brief Processes incoming Addr-reg-inform message.
+    ///
+    /// @param addr_reg_inf a message received from client
+    /// @return Addr-reg-reply message or null
+    Pkt6Ptr processAddrRegInform(const Pkt6Ptr& decline) {
+        AllocEngine::ClientContext6 ctx;
+        bool drop = !earlyGHRLookup(decline, ctx);
+        if (drop) {
+            return (Pkt6Ptr());
+        }
+        ctx.subnet_ = selectSubnet(decline, drop);
+        if (drop) {
+            return (Pkt6Ptr());
+        }
+        initContext(ctx, drop);
+        if (drop) {
+            return (Pkt6Ptr());
+        }
+        return (processAddrRegInform(ctx));
+    }
+
     using Dhcpv6Srv::processSolicit;
     using Dhcpv6Srv::processRequest;
     using Dhcpv6Srv::processRenew;
@@ -353,6 +374,7 @@ public:
     using Dhcpv6Srv::processRelease;
     using Dhcpv6Srv::processDecline;
     using Dhcpv6Srv::processInfRequest;
+    using Dhcpv6Srv::processAddrRegInform;
     using Dhcpv6Srv::processClientFqdn;
     using Dhcpv6Srv::createNameChangeRequests;
     using Dhcpv6Srv::selectSubnet;

src/bin/dhcp6/tests/http_control_socket_unittest.cc

@@ -910,11 +910,14 @@ BaseCtrlChannelDhcpv6Test::testControlChannelStats() {
         "pkt6-infrequest-received",
         "pkt6-dhcpv4-query-received",
         "pkt6-dhcpv4-response-received",
+        "pkt6-addr-reg-inform-received",
+        "pkt6-addr-reg-reply-received",
         "pkt6-unknown-received",
         "pkt6-sent",
         "pkt6-advertise-sent",
         "pkt6-reply-sent",
         "pkt6-dhcpv4-response-sent",
+        "pkt6-addr-reg-reply-sent",
         "pkt6-parse-failed",
         "pkt6-receive-drop",
         "v6-allocation-fail",

src/bin/dhcp6/tests/meson.build

@@ -102,6 +102,7 @@ co4 = shared_library(
 
 kea_dhcp6_tests = executable(
     'kea-dhcp6-tests',
+    'addr_reg_unittest.cc',
     'classify_unittest.cc',
     'client_handler_unittest.cc',
     'config_backend_unittest.cc',