[2902] Added unit test checking reception of the packet over INET DGRAM.

src/lib/dhcp/tests/pkt_filter_inet_unittest.cc

@@ -27,9 +27,14 @@ using namespace isc::dhcp;
 
 namespace {
 
+/// Port number used by tests.
 const uint16_t PORT = 10067;
+/// Size of the buffer holding received packets.
 const size_t RECV_BUF_SIZE = 2048;
 
+/// This class handles has simple algorithm checking
+/// presence of loopback interface and initializing
+/// its index.
 class PktFilterInetTest : public ::testing::Test {
 public:
     PktFilterInetTest() {
@@ -185,4 +190,67 @@ TEST_F(PktFilterInetTest, send) {
     EXPECT_EQ(pkt->getHlen(), rcvd_pkt->getHlen());
 }
 
+// This test verifies that the DHCPv4 packet is correctly received via
+// INET datagram socket and that it matches sent packet.
+TEST_F(PktFilterInetTest, receive) {
+    // Let's create a DHCPv4 packet.
+    Pkt4Ptr pkt(new Pkt4(DHCPOFFER, 0));
+    ASSERT_TRUE(pkt);
+
+    // Set required fields.
+    pkt->setLocalAddr(IOAddress("127.0.0.1"));
+    pkt->setRemotePort(PORT);
+    pkt->setLocalPort(PORT + 1);
+    pkt->setIndex(ifindex_);
+    pkt->setIface(ifname_);
+    pkt->setHops(6);
+    pkt->setSecs(42);
+    pkt->setCiaddr(IOAddress("192.0.2.1"));
+    pkt->setSiaddr(IOAddress("192.0.2.2"));
+    pkt->setYiaddr(IOAddress("192.0.2.3"));
+    pkt->setGiaddr(IOAddress("192.0.2.4"));
+
+    // Create the on-wire data.
+    ASSERT_NO_THROW(pkt->pack());
+
+    // Packet will be sent over loopback interface.
+    Iface iface(ifname_, ifindex_);
+    IOAddress addr("127.0.0.1");
+
+    // Create an instance of the class which we are testing.
+    PktFilterInet pkt_filter;
+    // Open socket. We don't check that the socket has appropriate
+    // options and family set because we have checked that in the
+    // openSocket test already.
+    socket_ = pkt_filter.openSocket(iface, addr, PORT, false, false);
+    ASSERT_GE(socket_, 0);
+
+    // Send the packet over the socket.
+    ASSERT_NO_THROW(pkt_filter.send(iface, socket_, pkt));
+
+    // Receive the packet.
+    SocketInfo socket_info(socket_, IOAddress("127.0.0.1"), PORT);
+    Pkt4Ptr rcvd_pkt = pkt_filter.receive(iface, socket_info);
+    // Check that the packet has been correctly received.
+    ASSERT_TRUE(rcvd_pkt);
+
+    // Parse the packet.
+    ASSERT_NO_THROW(rcvd_pkt->unpack());
+
+    // Verify that the received packet matches sent packet.
+    EXPECT_EQ(pkt->getHops(), rcvd_pkt->getHops());
+    EXPECT_EQ(pkt->getOp(),   rcvd_pkt->getOp());
+    EXPECT_EQ(pkt->getSecs(), rcvd_pkt->getSecs());
+    EXPECT_EQ(pkt->getFlags(), rcvd_pkt->getFlags());
+    EXPECT_EQ(pkt->getCiaddr(), rcvd_pkt->getCiaddr());
+    EXPECT_EQ(pkt->getSiaddr(), rcvd_pkt->getSiaddr());
+    EXPECT_EQ(pkt->getYiaddr(), rcvd_pkt->getYiaddr());
+    EXPECT_EQ(pkt->getGiaddr(), rcvd_pkt->getGiaddr());
+    EXPECT_EQ(pkt->getTransid(), rcvd_pkt->getTransid());
+    EXPECT_TRUE(pkt->getSname() == rcvd_pkt->getSname());
+    EXPECT_TRUE(pkt->getFile() == rcvd_pkt->getFile());
+    EXPECT_EQ(pkt->getHtype(), rcvd_pkt->getHtype());
+    EXPECT_EQ(pkt->getHlen(), rcvd_pkt->getHlen());
+}
+
 } // anonymous namespace