pdcp_rx: add test for received duplicates

Author: robertfalkenberg

tests/unittests/pdcp/pdcp_rx_test.cpp

@@ -178,6 +178,86 @@ TEST_P(pdcp_rx_test, rx_out_of_order)
   EXPECT_EQ(test_spy.get_error_counter(), 0);
 }
 
+/// Test reception of duplicate PDCP PDUs
+TEST_P(pdcp_rx_test, rx_duplicate)
+{
+  init(GetParam());
+  auto test_rx_out_of_order = [this](uint32_t count) {
+    srsran::test_delimit_logger delimiter("RX duplicate test. SN_SIZE={} COUNT=[{}, {}]", sn_size, count + 1, count);
+
+    pdcp_rx->configure_security(sec_cfg, security::integrity_enabled::on, security::ciphering_enabled::on);
+
+    byte_buffer test_pdu1;
+    get_test_pdu(count, test_pdu1);
+    byte_buffer test_pdu2;
+    get_test_pdu(count + 1, test_pdu2);
+    byte_buffer test_pdu2_dup;
+    get_test_pdu(count + 1, test_pdu2_dup);
+    byte_buffer test_pdu3;
+    get_test_pdu(count + 2, test_pdu3);
+    pdcp_rx_state init_state = {.rx_next = count, .rx_deliv = count, .rx_reord = 0};
+    pdcp_rx->set_state(init_state);
+
+    pdcp_rx->handle_pdu(byte_buffer_chain::create(std::move(test_pdu2)).value());
+
+    // Wait for crypto and reordering
+    wait_pending_crypto();
+    worker.run_pending_tasks();
+    ASSERT_EQ(0, test_frame->sdu_queue.size());
+    // check rx_reord matches rx_next matches count + 2
+    EXPECT_EQ(pdcp_rx->get_state().rx_reord, count + 2);
+    EXPECT_EQ(pdcp_rx->get_state().rx_reord, pdcp_rx->get_state().rx_next);
+
+    pdcp_rx->handle_pdu(byte_buffer_chain::create(std::move(test_pdu3)).value());
+
+    // Wait for crypto and reordering
+    wait_pending_crypto();
+    worker.run_pending_tasks();
+    ASSERT_EQ(0, test_frame->sdu_queue.size());
+    // check rx_reord still maches count + 2, i.e did not change because t_reord is already running; rx_next moved on
+    EXPECT_EQ(pdcp_rx->get_state().rx_reord, count + 2);
+    EXPECT_EQ(pdcp_rx->get_state().rx_next, count + 3);
+
+    // Send the duplicate
+    pdcp_rx->handle_pdu(byte_buffer_chain::create(std::move(test_pdu2_dup)).value());
+
+    // Wait for crypto and reordering
+    wait_pending_crypto();
+    worker.run_pending_tasks();
+    ASSERT_EQ(0, test_frame->sdu_queue.size());
+    // check rx_reord still maches count + 2
+    EXPECT_EQ(pdcp_rx->get_state().rx_reord, count + 2);
+    EXPECT_EQ(pdcp_rx->get_state().rx_next, count + 3);
+
+    pdcp_rx->handle_pdu(byte_buffer_chain::create(std::move(test_pdu1)).value());
+
+    // Wait for crypto and reordering
+    wait_pending_crypto();
+    worker.run_pending_tasks();
+    ASSERT_EQ(3, test_frame->sdu_queue.size());
+    while (not test_frame->sdu_queue.empty()) {
+      ASSERT_EQ(test_frame->sdu_queue.front(), sdu1);
+      test_frame->sdu_queue.pop();
+    }
+  };
+
+  if (sn_size == pdcp_sn_size::size12bits) {
+    test_rx_out_of_order(0);
+    test_rx_out_of_order(2047);
+    test_rx_out_of_order(4095);
+  } else if (sn_size == pdcp_sn_size::size18bits) {
+    test_rx_out_of_order(0);
+    test_rx_out_of_order(131071);
+    test_rx_out_of_order(262143);
+  } else {
+    FAIL();
+  }
+
+  // No warnings or errors
+  EXPECT_EQ(test_spy.get_warning_counter(), 0);
+  EXPECT_EQ(test_spy.get_error_counter(), 0);
+}
+
 /// Test out of order reception of PDUs.
 /// The out-of-order PDU is received after the t-Reordering expires.
 TEST_P(pdcp_rx_test, rx_reordering_timer)