[#3230] Initial commit

Adds dhcp::PktEvent, modifies packet filters and tests

src/lib/dhcp/pkt.*
    Add PktEvent class, add stack and methods to Pkt

src/lib/dhcp/pkt_filter_bpf.cc
    PktFilterBPF::receive() - fetch timestamp from bpfhdr,
    add SOCKET_RECEIVED and BUFFER_READ events

    PktFilterBPF::send() - add RESPONSE_SENT event

src/lib/dhcp/pkt_filter_inet.cc
    PktFilterInet::openSocket() - enable SO_TIMESTAMP socket option

    PktFilterInet::receive() - fetch SO_TIMESTAMP via CMSG,
    add SOCKET_RECEIVED and BUFFER_READ events

    PktFilterInet::send() - add RESPONSE_SENT event

src/lib/dhcp/pkt_filter_inet6.cc
    PktFilterInet6::openSocket() - enable SO_TIMESTAMP socket option

    PktFilterInet6::receive() - fetch SO_TIMESTAMP via CMSG,
    add SOCKET_RECEIVED and BUFFER_READ events

    PktFilterInet::send() - add RESPONSE_SENT event

src/lib/dhcp/pkt_filter_lpf.cc

    PktFilterLPF::openSocket() - enable SO_TIMESTAMP socket option
    PktFilterLPF::receive() - added conditonal compilation version based
    on WITH_CMSG macro that fetches SO_TIMESTAMP and add SOCKET_RECEIVED
    and BUFFER_READ events

    PktFilterLPF::send() - add RESPONSE_SENT event

src/lib/dhcp/tests/pkt4_unittest.cc
    TEST_F(Pkt4Test, PktEvents) - new test

src/lib/dhcp/tests/pkt6_unittest.cc
    TEST_F(Pkt6Test, PktEvents) - new test

src/lib/dhcp/tests/pkt_filter6_test_utils.cc
src/lib/dhcp/tests/pkt_filter6_test_utils.h
src/lib/dhcp/tests/pkt_filter_inet6_unittest.cc
src/lib/dhcp/tests/pkt_filter_inet_unittest.cc
src/lib/dhcp/tests/pkt_filter_test_utils.cc
src/lib/dhcp/tests/pkt_filter_test_utils.h
    Updated tests to check PktEvent stack contents

src/lib/dhcp/tests/pkt_filter_bpf_unittest.cc
src/lib/dhcp/tests/pkt_filter_lpf_unittest.cc
    Updated tests to check PktEvent stack contents,
    Changed DISABLED_ tests to use SKIP_IF(notRoot)

1 files changed, 67 insertions, 0 deletions

diff --git a/src/lib/dhcp/tests/pkt4_unittest.cc b/src/lib/dhcp/tests/pkt4_unittest.cc
index db07f2bd58..c9f120eeef 100644
--- a/src/lib/dhcp/tests/pkt4_unittest.cc
+++ b/src/lib/dhcp/tests/pkt4_unittest.cc
@@ -1525,4 +1525,71 @@ TEST_F(Pkt4Test, getHWAddrLabel) {
     EXPECT_EQ ("hwaddr=02:04:06:08:0a:0c", pkt.getHWAddrLabel());
 }
 
+// Exercises packet event stack and helper functions.
+TEST_F(Pkt4Test, PktEvents) {
+    // Get current time.
+    auto start_time = PktEvent::now();
+
+    // Verify that a set time is not equal to an EMPTY_TIME.
+    ASSERT_NE(start_time, PktEvent::EMPTY_TIME());
+
+    // Create a test packet.
+    scoped_ptr<Pkt4> pkt(new Pkt4(DHCPOFFER, 1234));
+
+    // Upon creation, the events table should be empty.
+    ASSERT_TRUE(pkt->getPktEvents().empty());
+
+    // An non-existant event should return an empty time.
+    auto event_time = pkt->getPktEventTime(PktEvent::BUFFER_READ);
+    ASSERT_EQ(event_time, PktEvent::EMPTY_TIME());
+
+    // Sleep for 200 microseconds to put some distance between now and start_time.
+    usleep(200);
+
+    // Should be able to add an event, defaulting the event time to current time.
+    pkt->addPktEvent(PktEvent::BUFFER_READ);
+    event_time = pkt->getPktEventTime(PktEvent::BUFFER_READ);
+    ASSERT_GT(event_time, start_time);
+
+    // Should be able to overwrite an existing event's time.
+    pkt->setPktEvent(PktEvent::BUFFER_READ, start_time);
+    event_time = pkt->getPktEventTime(PktEvent::BUFFER_READ);
+    ASSERT_EQ(event_time, start_time);
+
+    // Should be able to add an event with an explicit time.
+    pkt->addPktEvent(PktEvent::RESPONSE_SENT, start_time);
+    event_time = pkt->getPktEventTime(PktEvent::RESPONSE_SENT);
+    ASSERT_EQ(event_time, start_time);
+
+    // Should be able to fetch the list of events.
+    const auto& events = pkt->getPktEvents();
+    ASSERT_FALSE(events.empty());
+    auto event = events.begin();
+    ASSERT_EQ((*event).label_, PktEvent::BUFFER_READ);
+    ++event;
+    ASSERT_EQ((*event).label_, PktEvent::RESPONSE_SENT);
+
+    // Discard the event stack contents.
+    pkt->clearPktEvents();
+    ASSERT_TRUE(pkt->getPktEvents().empty());
+
+    // Verify dumpPktEvent terse output. Also serves to
+    // verify adding events using struct timeval.
+    struct timeval log_time = {1706802676, 100};
+    struct timeval log_time_plus = {1706802676, 250};
+    pkt->addPktEvent("first-event", log_time);
+    pkt->addPktEvent("second-event", log_time_plus);
+    std::string log = pkt->dumpPktEvents();
+    EXPECT_EQ(log, "2024-Feb-01 15:51:16.000100 : first-event, 2024-Feb-01 15:51:16.000250 : second-event");
+
+    // Verify dumpPktEvent verbose output.
+    log = pkt->dumpPktEvents(true);
+    EXPECT_EQ(log,
+              "Event log: \n"
+              "2024-Feb-01 15:51:16.000100 : first-event\n"
+              "2024-Feb-01 15:51:16.000250 : second-event elapsed: 00:00:00.000150\n"
+              "total elapsed: 00:00:00.000150");
+}
+
+
 } // end of anonymous namespace