[4106_update] Ported and improved code from old trac4106 including unit tests

src/bin/dhcp4/ctrl_dhcp4_srv.cc

@@ -192,7 +192,7 @@ ControlledDhcpv4Srv::processConfig(isc::data::ConstElementPtr config) {
 
     // Setup DHCPv4-over-DHCPv6 IPC
     try {
-        Dhcp4o6Ipc::instance().open();
+        Dhcp4to6Ipc::instance().open();
     } catch (const std::exception& ex) {
         std::ostringstream err;
         err << "error starting DHCPv4-over-DHCPv6 IPC "

src/bin/dhcp4/dhcp4_dhcp4o6_ipc.cc

@@ -24,14 +24,14 @@ using namespace std;
 namespace isc {
 namespace dhcp {
 
-Dhcp4o6Ipc::Dhcp4o6Ipc() : Dhcp4o6IpcBase() {}
+Dhcp4to6Ipc::Dhcp4to6Ipc() : Dhcp4o6IpcBase() {}
 
-Dhcp4o6Ipc& Dhcp4o6Ipc::instance() {
-    static Dhcp4o6Ipc dhcp4o6_ipc;
-    return (dhcp4o6_ipc);
+Dhcp4to6Ipc& Dhcp4to6Ipc::instance() {
+    static Dhcp4to6Ipc dhcp4to6_ipc;
+    return (dhcp4to6_ipc);
 }
 
-void Dhcp4o6Ipc::open() {
+void Dhcp4to6Ipc::open() {
     uint32_t port = CfgMgr::instance().getStagingCfg()->getDhcp4o6Port();
     if (port == 0) {
         Dhcp4o6IpcBase::close();
@@ -42,31 +42,48 @@ void Dhcp4o6Ipc::open() {
     }
 
     int old_fd = socket_fd_;
-    socket_fd_ = Dhcp4o6IpcBase::open(static_cast<uint16_t>(port), 4);
+    socket_fd_ = Dhcp4o6IpcBase::open(static_cast<uint16_t>(port),
+                                      ENDPOINT_TYPE_V4);
     if ((old_fd == -1) && (socket_fd_ != old_fd)) {
-        IfaceMgr::instance().addExternalSocket(socket_fd_, Dhcp4o6Ipc::handler);
+        IfaceMgr::instance().addExternalSocket(socket_fd_,
+                                               Dhcp4to6Ipc::handler);
     }
 }
 
-void Dhcp4o6Ipc::handler() {
-    Dhcp4o6Ipc& ipc = Dhcp4o6Ipc::instance();
+void Dhcp4to6Ipc::handler() {
+    Dhcp4to6Ipc& ipc = Dhcp4to6Ipc::instance();
+
+    // Reset received message in case we return from this method before the
+    // received message pointer is updated.
+    ipc.received_.reset();
+
+    // Receive message from the IPC socket.
     Pkt6Ptr pkt = ipc.receive();
     if (!pkt) {
         return;
     }
 
+    // Each message must contain option holding DHCPv4 message.
     OptionCollection msgs = pkt->getOptions(D6O_DHCPV4_MSG);
-    if (msgs.size() != 1) {
-        return;
+    if (msgs.empty()) {
+        isc_throw(Dhcp4o6IpcError, "DHCPv4 message option not present in the"
+                  " DHCPv4o6 message received by the DHCPv4 server");
+    } else if (msgs.size() > 1) {
+        isc_throw(Dhcp4o6IpcError, "expected exactly one DHCPv4 message within"
+                  " DHCPv4 message option received by the DHCPv4 server");
     }
-    OptionPtr msg = pkt->getOption(D6O_DHCPV4_MSG);
+
+    OptionPtr msg = msgs.begin()->second;
     if (!msg) {
-        isc_throw(Unexpected, "Can't get DHCPv4 message option");
+        isc_throw(Dhcp4o6IpcError, "null DHCPv4 message option in the"
+                  " DHCPv4o6 message received by the DHCPv4 server");
     }
-    instance().received_.reset(new Pkt4o6(msg->getData(), pkt));
+
+    // Record this message.
+    ipc.received_.reset(new Pkt4o6(msg->getData(), pkt));
 }
 
-Pkt4o6Ptr& Dhcp4o6Ipc::getReceived() {
+Pkt4o6Ptr& Dhcp4to6Ipc::getReceived() {
     return (received_);
 }
 

src/bin/dhcp4/dhcp4_dhcp4o6_ipc.h

@@ -28,23 +28,23 @@ namespace isc {
 namespace dhcp {
 
 /// @brief Handles DHCPv4-over-DHCPv6 IPC on the DHCPv4 server side
-class Dhcp4o6Ipc : public Dhcp4o6IpcBase {
+class Dhcp4to6Ipc : public Dhcp4o6IpcBase {
 protected:
     /// @brief Constructor
     ///
     /// Default constructor
-    Dhcp4o6Ipc();
+    Dhcp4to6Ipc();
 
     /// @brief Destructor.
-    virtual ~Dhcp4o6Ipc() { }
+    virtual ~Dhcp4to6Ipc() { }
 
 public:
-    /// @brief Returns pointer to the sole instance of Dhcp4o6Ipc
+    /// @brief Returns pointer to the sole instance of Dhcp4to6Ipc
     ///
-    /// Dhcp4o6Ipc is a singleton class
+    /// Dhcp4to6Ipc is a singleton class
     ///
     /// @return the only existing instance of DHCP4o6 IPC
-    static Dhcp4o6Ipc& instance();
+    static Dhcp4to6Ipc& instance();
 
     /// @brief Open communication socket
     ///

src/bin/dhcp4/tests/Makefile.am

@@ -93,6 +93,7 @@ dhcp4_unittests_SOURCES += release_unittest.cc
 dhcp4_unittests_SOURCES += out_of_range_unittest.cc
 dhcp4_unittests_SOURCES += decline_unittest.cc
 dhcp4_unittests_SOURCES += kea_controller_unittest.cc
+dhcp4_unittests_SOURCES += dhcp4_dhcp4o6_ipc_unittest.cc
 
 nodist_dhcp4_unittests_SOURCES = marker_file.h test_libraries.h
 

src/bin/dhcp4/tests/dhcp4_dhcp4o6_ipc_unittest.cc

+// Copyright (C) 2015-2016 Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include <config.h>
+#include <asiolink/io_address.h>
+#include <dhcp/pkt4o6.h>
+#include <dhcp/pkt6.h>
+#include <dhcp/tests/iface_mgr_test_config.h>
+#include <dhcp4/dhcp4_dhcp4o6_ipc.h>
+#include <dhcpsrv/cfgmgr.h>
+#include <dhcpsrv/testutils/dhcp4o6_test_ipc.h>
+#include <gtest/gtest.h>
+#include <stdint.h>
+
+using namespace isc;
+using namespace isc::asiolink;
+using namespace isc::dhcp;
+using namespace isc::dhcp::test;
+using namespace isc::util;
+
+namespace {
+
+/// @brief Port number used in tests.
+const uint16_t TEST_PORT = 32000;
+
+/// @brief Define short name for the test IPC.
+typedef Dhcp4o6TestIpc TestIpc;
+
+/// @brief Test fixture class for DHCPv4 endpoint of DHCPv4o6 IPC.
+class Dhcp4to6IpcTest : public ::testing::Test {
+public:
+
+    /// @brief Constructor
+    ///
+    /// Configures IPC to use a test port. It also provides a fake
+    /// configuration of interfaces.
+    Dhcp4to6IpcTest()
+        : iface_mgr_test_config_(true) {
+        configurePort(TEST_PORT);
+    }
+
+    /// @brief Configure DHCP4o6 port.
+    ///
+    /// @param port New port.
+    void configurePort(uint16_t port);
+
+    /// @brief Creates an instance of the DHCPv4o6 Message option.
+    ///
+    /// @return Pointer to the instance of the DHCPv4-query Message option.
+    OptionPtr createDHCPv4MsgOption() const;
+
+private:
+
+    /// @brief Provides fake configuration of interfaces.
+    IfaceMgrTestConfig iface_mgr_test_config_;
+
+};
+
+void
+Dhcp4to6IpcTest::configurePort(uint16_t port) {
+    CfgMgr::instance().getStagingCfg()->setDhcp4o6Port(port);
+}
+
+OptionPtr
+Dhcp4to6IpcTest::createDHCPv4MsgOption() const {
+    // Create the DHCPv4 message.
+    Pkt4Ptr pkt(new Pkt4(DHCPREQUEST, 1234));
+    // Make a wire representation of the DHCPv4 message.
+    pkt->pack();
+    OutputBuffer& output_buffer = pkt->getBuffer();
+    const uint8_t* data = static_cast<const uint8_t*>(output_buffer.getData());
+    OptionBuffer option_buffer(data, data + output_buffer.getLength());
+
+    // Create the DHCPv4 Message option holding the created message.
+    OptionPtr opt_msg(new Option(Option::V6, D6O_DHCPV4_MSG, option_buffer));
+    return (opt_msg);
+}
+
+// This test verifies that the IPC returns an error when trying to bind
+// to the out of range port.
+TEST_F(Dhcp4to6IpcTest, invalidPortError) {
+    // Create instance of the IPC endpoint under test with out-of-range port.
+    configurePort(65535);
+    Dhcp4to6Ipc& ipc = Dhcp4to6Ipc::instance();
+    EXPECT_THROW(ipc.open(), isc::OutOfRange);
+}
+
+// This test verifies that the DHCPv4 endpoint of the DHCPv4o6 IPC can
+// receive messages.
+TEST_F(Dhcp4to6IpcTest, receive) {
+    // Create instance of the IPC endpoint under test.
+    Dhcp4to6Ipc& ipc = Dhcp4to6Ipc::instance();
+    // Create instance of the IPC endpoint being used as a source of messages.
+    TestIpc src_ipc(TEST_PORT, TestIpc::ENDPOINT_TYPE_V6);
+
+    // Open both endpoints.
+    ASSERT_NO_THROW(ipc.open());
+    ASSERT_NO_THROW(src_ipc.open());
+
+    // Create message to be sent over IPC.
+    Pkt6Ptr pkt(new Pkt6(DHCPV6_DHCPV4_QUERY, 1234));
+    pkt->addOption(createDHCPv4MsgOption());
+    pkt->setIface("eth0");
+    pkt->setRemoteAddr(IOAddress("2001:db8:1::123"));
+    ASSERT_NO_THROW(pkt->pack());
+
+    // Send and wait up to 1 second to receive it.
+    ASSERT_NO_THROW(src_ipc.send(pkt));
+    ASSERT_NO_THROW(IfaceMgr::instance().receive6(1, 0));
+
+    // Make sure that the message has been received.
+    Pkt4o6Ptr pkt_received = ipc.getReceived();
+    ASSERT_TRUE(pkt_received);
+    Pkt6Ptr pkt6_received = pkt_received->getPkt6();
+    ASSERT_TRUE(pkt6_received);
+    EXPECT_EQ("eth0", pkt6_received->getIface());
+    EXPECT_EQ("2001:db8:1::123", pkt6_received->getRemoteAddr().toText());
+}
+
+// This test verifies that message with multiple DHCPv4 query options
+// is rejected.
+TEST_F(Dhcp4to6IpcTest, receiveMultipleQueries) {
+    // Create instance of the IPC endpoint under test.
+    Dhcp4to6Ipc& ipc = Dhcp4to6Ipc::instance();
+    // Create instance of the IPC endpoint being used as a source of messages.
+    TestIpc src_ipc(TEST_PORT, TestIpc::ENDPOINT_TYPE_V6);
+
+    // Open both endpoints.
+    ASSERT_NO_THROW(ipc.open());
+    ASSERT_NO_THROW(src_ipc.open());
+
+    // Create message to be sent over IPC.
+    Pkt6Ptr pkt(new Pkt6(DHCPV6_DHCPV4_QUERY, 1234));
+    // Add two DHCPv4 query options.
+    pkt->addOption(createDHCPv4MsgOption());
+    pkt->addOption(createDHCPv4MsgOption());
+    pkt->setIface("eth0");
+    pkt->setRemoteAddr(IOAddress("2001:db8:1::123"));
+    ASSERT_NO_THROW(pkt->pack());
+
+    // Send message.
+    ASSERT_NO_THROW(src_ipc.send(pkt));
+    // Reception handler should throw exception.
+    EXPECT_THROW(IfaceMgr::instance().receive6(1, 0), Dhcp4o6IpcError);
+}
+
+// This test verifies that message with no DHCPv4 query options is rejected.
+TEST_F(Dhcp4to6IpcTest, receiveNoQueries) {
+    // Create instance of the IPC endpoint under test.
+    Dhcp4to6Ipc& ipc = Dhcp4to6Ipc::instance();
+    // Create instance of the IPC endpoint being used as a source of messages.
+    TestIpc src_ipc(TEST_PORT, TestIpc::ENDPOINT_TYPE_V6);
+
+    // Open both endpoints.
+    ASSERT_NO_THROW(ipc.open());
+    ASSERT_NO_THROW(src_ipc.open());
+
+    // Create message to be sent over IPC without DHCPv4 query option.
+    Pkt6Ptr pkt(new Pkt6(DHCPV6_DHCPV4_QUERY, 1234));
+    pkt->setIface("eth0");
+    pkt->setRemoteAddr(IOAddress("2001:db8:1::123"));
+    ASSERT_NO_THROW(pkt->pack());
+
+    // Send message.
+    ASSERT_NO_THROW(src_ipc.send(pkt));
+    // Reception handler should throw exception.
+    EXPECT_THROW(IfaceMgr::instance().receive6(1, 0), Dhcp4o6IpcError);
+}
+
+} // end of anonymous namespace

src/bin/dhcp6/ctrl_dhcp6_srv.cc

@@ -216,7 +216,7 @@ ControlledDhcpv6Srv::processConfig(isc::data::ConstElementPtr config) {
 
     // Setup DHCPv4-over-DHCPv6 IPC
     try {
-        Dhcp4o6Ipc::instance().open();
+        Dhcp6to4Ipc::instance().open();
     } catch (const std::exception& ex) {
         std::ostringstream err;
         err << "error starting DHCPv4-over-DHCPv6 IPC "

src/bin/dhcp6/dhcp6_dhcp4o6_ipc.cc

@@ -24,14 +24,14 @@ using namespace std;
 namespace isc {
 namespace dhcp {
 
-Dhcp4o6Ipc::Dhcp4o6Ipc() : Dhcp4o6IpcBase() {}
+Dhcp6to4Ipc::Dhcp6to4Ipc() : Dhcp4o6IpcBase() {}
 
-Dhcp4o6Ipc& Dhcp4o6Ipc::instance() {
-    static Dhcp4o6Ipc dhcp4o6_ipc;
-    return (dhcp4o6_ipc);
+Dhcp6to4Ipc& Dhcp6to4Ipc::instance() {
+    static Dhcp6to4Ipc dhcp6to4_ipc;
+    return (dhcp6to4_ipc);
 }
 
-void Dhcp4o6Ipc::open() {
+void Dhcp6to4Ipc::open() {
     uint32_t port = CfgMgr::instance().getStagingCfg()->getDhcp4o6Port();
     if (port == 0) {
         Dhcp4o6IpcBase::close();
@@ -42,30 +42,38 @@ void Dhcp4o6Ipc::open() {
     }
 
     int old_fd = socket_fd_;
-    socket_fd_ = Dhcp4o6IpcBase::open(static_cast<uint16_t>(port), 6);
+    socket_fd_ = Dhcp4o6IpcBase::open(static_cast<uint16_t>(port),
+                                      ENDPOINT_TYPE_V6);
     if ((old_fd == -1) && (socket_fd_ != old_fd)) {
-        IfaceMgr::instance().addExternalSocket(socket_fd_, Dhcp4o6Ipc::handler);
+        IfaceMgr::instance().addExternalSocket(socket_fd_,
+                                               Dhcp6to4Ipc::handler);
     }
 }
 
-void Dhcp4o6Ipc::handler() {
-    Dhcp4o6Ipc& ipc = Dhcp4o6Ipc::instance();
+void Dhcp6to4Ipc::handler() {
+    Dhcp6to4Ipc& ipc = Dhcp6to4Ipc::instance();
+
+    // Receive message from IPC.
     Pkt6Ptr pkt = ipc.receive();
     if (!pkt) {
         return;
     }
 
+    // The received message has been unpacked by the receive() function. This
+    // method could have modified the message so it's better to pack() it
+    // again because we'll be forwarding it to a client.
     isc::util::OutputBuffer& buf = pkt->getBuffer();
     buf.clear();
     pkt->pack();
 
-    uint8_t msg_type = buf[0];
+    uint8_t msg_type = pkt->getType();
     if ((msg_type == DHCPV6_RELAY_FORW) || (msg_type == DHCPV6_RELAY_REPL)) {
         pkt->setRemotePort(DHCP6_SERVER_PORT);
     } else {
         pkt->setRemotePort(DHCP6_CLIENT_PORT);
     }
 
+    // Forward packet to the client.
     IfaceMgr::instance().send(pkt);
     // processStatsSent(pkt);
 }

src/bin/dhcp6/dhcp6_dhcp4o6_ipc.h

@@ -15,7 +15,7 @@
 #ifndef DHCP6_DHCP4O6_IPC_H
 #define DHCP6_DHCP4O6_IPC_H
 
-/// @file dhcp6_dhcp4o6_ipc.h Defines the Dhcp4o6Ipc class.
+/// @file dhcp6_dhcp4o6_ipc.h Defines the Dhcp6to4Ipc class.
 /// This file defines the class Kea uses to act as the DHCPv6 server
 /// side of DHCPv4-over-DHCPv6 communication between servers.
 ///
@@ -26,23 +26,23 @@ namespace isc {
 namespace dhcp {
 
 /// @brief Handles DHCPv4-over-DHCPv6 IPC on the DHCPv6 server side
-class Dhcp4o6Ipc : public Dhcp4o6IpcBase {
+class Dhcp6to4Ipc : public Dhcp4o6IpcBase {
 protected:
     /// @brief Constructor
     ///
     /// Default constructor
-    Dhcp4o6Ipc();
+    Dhcp6to4Ipc();
 
     /// @brief Destructor.
-    virtual ~Dhcp4o6Ipc() { }
+    virtual ~Dhcp6to4Ipc() { }
 
 public:
-    /// @brief Returns pointer to the sole instance of Dhcp4o6Ipc
+    /// @brief Returns pointer to the sole instance of Dhcp6to4Ipc
     ///
-    /// Dhcp4o6Ipc is a singleton class
+    /// Dhcp6to4Ipc is a singleton class
     ///
     /// @return the only existing instance of DHCP4o6 IPC
-    static Dhcp4o6Ipc& instance();
+    static Dhcp6to4Ipc& instance();
 
     /// @brief Open communication socket
     ///

src/bin/dhcp6/dhcp6_srv.cc

@@ -213,7 +213,7 @@ Dhcpv6Srv::~Dhcpv6Srv() {
     }
 
     try {
-        Dhcp4o6Ipc::instance().close();
+        Dhcp6to4Ipc::instance().close();
     } catch(const std::exception& ex) {
         // Highly unlikely, but lets Report it but go on
         // LOG_ERROR(dhcp6_logger, DHCP6_SRV_DHCP4O6_ERROR).arg(ex.what());

src/bin/dhcp6/tests/Makefile.am

@@ -94,8 +94,8 @@ dhcp6_unittests_SOURCES += confirm_unittest.cc
 dhcp6_unittests_SOURCES += infrequest_unittest.cc
 dhcp6_unittests_SOURCES += decline_unittest.cc
 dhcp6_unittests_SOURCES += dhcp6_message_test.cc dhcp6_message_test.h
-
 dhcp6_unittests_SOURCES += kea_controller_unittest.cc
+dhcp6_unittests_SOURCES += dhcp6_dhcp4o6_ipc_unittest.cc
 
 nodist_dhcp6_unittests_SOURCES  = marker_file.h test_libraries.h
 

src/bin/dhcp6/tests/dhcp6_dhcp4o6_ipc_unittest.cc

+// Copyright (C) 2015-2016 Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include <config.h>
+#include <asiolink/io_address.h>
+#include <dhcp/pkt6.h>
+#include <dhcp/iface_mgr.h>
+#include <dhcp/tests/iface_mgr_test_config.h>
+#include <dhcp/tests/pkt_filter6_test_stub.h>
+#include <dhcp6/dhcp6_dhcp4o6_ipc.h>
+#include <dhcpsrv/cfgmgr.h>
+#include <dhcpsrv/testutils/dhcp4o6_test_ipc.h>
+#include <gtest/gtest.h>
+#include <stdint.h>
+
+using namespace isc;
+using namespace isc::asiolink;
+using namespace isc::dhcp;
+using namespace isc::dhcp::test;
+using namespace isc::util;
+
+namespace {
+
+/// @brief Port number used in tests.
+const uint16_t TEST_PORT = 32000;
+
+/// @brief Define short name for the test IPC.
+typedef Dhcp4o6TestIpc TestIpc;
+
+/// @brief Test fixture class for DHCPv4 endpoint of DHCPv4o6 IPC.
+class Dhcp6to4IpcTest : public ::testing::Test {
+public:
+
+    /// @brief Constructor
+    ///
+    /// Configures IPC to use a test port. It also provides a fake
+    /// configuration of interfaces and opens IPv6 sockets.
+    Dhcp6to4IpcTest()
+        : iface_mgr_test_config_(true) {
+        IfaceMgr::instance().openSockets6();
+        configurePort(TEST_PORT);
+    }
+
+    /// @brief Configure DHCP4o6 port.
+    ///
+    /// @param port New port.
+    void configurePort(const uint16_t port);
+
+    /// @brief Creates an instance of the DHCPv4o6 Message option.
+    ///
+    /// @return Pointer to the instance of the DHCPv4-query Message option.
+    OptionPtr createDHCPv4MsgOption() const;
+
+private:
+
+    /// @brief Provides fake configuration of interfaces.
+    IfaceMgrTestConfig iface_mgr_test_config_;
+};
+
+void
+Dhcp6to4IpcTest::configurePort(const uint16_t port) {
+    CfgMgr::instance().getStagingCfg()->setDhcp4o6Port(port);
+}
+
+OptionPtr
+Dhcp6to4IpcTest::createDHCPv4MsgOption() const {
+    // Create the DHCPv4 message.
+    Pkt4Ptr pkt(new Pkt4(DHCPREQUEST, 1234));
+    // Make a wire representation of the DHCPv4 message.
+    pkt->pack();
+    OutputBuffer& output_buffer = pkt->getBuffer();
+    const uint8_t* data = static_cast<const uint8_t*>(output_buffer.getData());
+    OptionBuffer option_buffer(data, data + output_buffer.getLength());
+
+    // Create the DHCPv4 Message option holding the created message.
+    OptionPtr opt_msg(new Option(Option::V6, D6O_DHCPV4_MSG, option_buffer));
+    return (opt_msg);
+}
+
+// This test verifies that the IPC returns an error when trying to bind
+// to the out of range port.
+TEST_F(Dhcp6to4IpcTest, invalidPortError) {
+    // Create instance of the IPC endpoint under test with out-of-range port.
+    configurePort(65535);
+    Dhcp6to4Ipc& ipc = Dhcp6to4Ipc::instance();
+    EXPECT_THROW(ipc.open(), isc::OutOfRange);
+}
+
+// This test verifies that the DHCPv4 endpoint of the DHCPv4o6 IPC can
+// receive messages.
+TEST_F(Dhcp6to4IpcTest, receive) {
+    // Create instance of the IPC endpoint under test.
+    Dhcp6to4Ipc& ipc = Dhcp6to4Ipc::instance();
+    // Create instance of the IPC endpoint being used as a source of messages.
+    TestIpc src_ipc(TEST_PORT, TestIpc::ENDPOINT_TYPE_V4);
+
+    // Open both endpoints.
+    ASSERT_NO_THROW(ipc.open());
+    ASSERT_NO_THROW(src_ipc.open());
+
+    // Create message to be sent over IPC.
+    Pkt6Ptr pkt(new Pkt6(DHCPV6_DHCPV4_QUERY, 1234));
+    pkt->addOption(createDHCPv4MsgOption());
+    pkt->setIface("eth0");
+    pkt->setRemoteAddr(IOAddress("2001:db8:1::123"));
+    ASSERT_NO_THROW(pkt->pack());
+
+    // Send and wait up to 1 second to receive it.
+    ASSERT_NO_THROW(src_ipc.send(pkt));
+    ASSERT_NO_THROW(IfaceMgr::instance().receive6(1, 0));
+
+#if 0
+    // The stub packet filter exposes static function to retrieve messages
+    // sent over the fake sockets/interfaces. This is the message that the
+    // IPC endpoint should forward to the client after receiving it
+    // from the DHCPv4 server.
+    Pkt6Ptr forwarded = PktFilter6TestStub::popSent();
+    ASSERT_TRUE(forwarded);
+
+    // Verify the packet received.
+    EXPECT_EQ(DHCP6_CLIENT_PORT, forwarded->getRemotePort());
+    EXPECT_EQ(forwarded->getType(), pkt->getType());
+    EXPECT_TRUE(forwarded->getOption(D6O_DHCPV4_MSG));
+    EXPECT_EQ("eth0", forwarded->getIface());
+    EXPECT_EQ("2001:db8:1::123", forwarded->getRemoteAddr().toText());
+#endif
+}
+
+} // end of anonymous namespace

src/lib/dhcpsrv/dhcp4o6_ipc.cc

@@ -17,11 +17,12 @@
 #include <dhcp/dhcp6.h>
 #include <dhcp/iface_mgr.h>
 #include <dhcp/option6_addrlst.h>
+#include <dhcp/option_custom.h>
 #include <dhcp/option_string.h>
 #include <dhcp/option_vendor.h>
 #include <dhcpsrv/dhcp4o6_ipc.h>
-#include <dhcpsrv/dhcpsrv_log.h>
-
+#include <boost/pointer_cast.hpp>
+#include <errno.h>
 #include <netinet/in.h>
 #include <sys/fcntl.h>
 #include <string>
@@ -39,41 +40,36 @@ Dhcp4o6IpcBase::~Dhcp4o6IpcBase() {
     close();
 }
 
-int Dhcp4o6IpcBase::open(uint16_t port, int side) {
+int Dhcp4o6IpcBase::open(uint16_t port, EndpointType endpoint_type) {
+    // Don't check if the value is greater than 65534 as it is done
+    // by callers before they cast the value to 16 bits.
+
     if (port == port_) {