test_res_rtp.c

Go to the documentation of this file.

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2019, Sangoma, Inc.
 *
 * Ben Ford <[email protected]>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*!
 * \file
 * \brief RTP/RTCP Unit Tests
 *
 * \author Ben Ford <[email protected]>
 *
 */

/*** MODULEINFO
   <depend>TEST_FRAMEWORK</depend>
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

#include "asterisk/module.h"
#include "asterisk/test.h"
#include "asterisk/rtp_engine.h"
#include "asterisk/data_buffer.h"
#include "asterisk/format_cache.h"

enum test_type {
   TEST_TYPE_NONE = 0,  /* No special setup required */
   TEST_TYPE_NACK,      /* Enable NACK */
   TEST_TYPE_REMB,      /* Enable REMB */
};

static void ast_sched_context_destroy_wrapper(struct ast_sched_context *sched)
{
   if (sched) {
      ast_sched_context_destroy(sched);
   }
}

static int test_init_rtp_instances(struct ast_rtp_instance **instance1,
   struct ast_rtp_instance **instance2, struct ast_sched_context *test_sched,
   enum test_type type)
{
   struct ast_sockaddr addr;

   ast_sockaddr_parse(&addr, "127.0.0.1", 0);

   *instance1 = ast_rtp_instance_new("asterisk", test_sched, &addr, NULL);
   *instance2 = ast_rtp_instance_new("asterisk", test_sched, &addr, NULL);
   if (!instance1 || !instance2) {
      return -1;
   }

   ast_rtp_instance_set_prop(*instance1, AST_RTP_PROPERTY_RTCP, AST_RTP_INSTANCE_RTCP_MUX);
   ast_rtp_instance_set_prop(*instance2, AST_RTP_PROPERTY_RTCP, AST_RTP_INSTANCE_RTCP_MUX);

   if (type == TEST_TYPE_NACK) {
      ast_rtp_instance_set_prop(*instance1, AST_RTP_PROPERTY_RETRANS_RECV, 1);
      ast_rtp_instance_set_prop(*instance1, AST_RTP_PROPERTY_RETRANS_SEND, 1);
      ast_rtp_instance_set_prop(*instance2, AST_RTP_PROPERTY_RETRANS_RECV, 2);
      ast_rtp_instance_set_prop(*instance2, AST_RTP_PROPERTY_RETRANS_SEND, 2);
   } else if (type == TEST_TYPE_REMB) {
      ast_rtp_instance_set_prop(*instance1, AST_RTP_PROPERTY_REMB, 1);
      ast_rtp_instance_set_prop(*instance2, AST_RTP_PROPERTY_REMB, 1);
   }

   ast_rtp_instance_get_local_address(*instance1, &addr);
   ast_rtp_instance_set_remote_address(*instance2, &addr);

   ast_rtp_instance_get_local_address(*instance2, &addr);
   ast_rtp_instance_set_remote_address(*instance1, &addr);

   ast_rtp_instance_reset_test_engine(*instance1);

   ast_rtp_instance_activate(*instance1);
   ast_rtp_instance_activate(*instance2);

   return 0;
}

static void test_write_frames(struct ast_rtp_instance *instance, int seqno, int num)
{
   char data[320] = "";
   struct ast_frame frame_out = {
      .frametype = AST_FRAME_VOICE,
      .subclass.format = ast_format_ulaw,
      .data.ptr = data,
      .datalen = 160,
   };
   int index;

   ast_set_flag(&frame_out, AST_FRFLAG_HAS_SEQUENCE_NUMBER);

   for (index = 0; index < num; index++) {
      frame_out.seqno = seqno + index;
      ast_rtp_instance_write(instance, &frame_out);
   }
}

static void test_read_frames(struct ast_rtp_instance *instance, int num)
{
   struct ast_frame *frame_in;
   int index;

   for (index = 0; index < num; index++) {
      frame_in = ast_rtp_instance_read(instance, 0);
      if (frame_in) {
         ast_frfree(frame_in);
      }
   }
}

static void test_write_and_read_frames(struct ast_rtp_instance *instance1,
   struct ast_rtp_instance *instance2, int seqno, int num)
{
   test_write_frames(instance1, seqno, num);
   test_read_frames(instance2, num);
}

AST_TEST_DEFINE(nack_no_packet_loss)
{
   RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_rtp_instance *, instance2, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_sched_context *, test_sched, NULL, ast_sched_context_destroy_wrapper);

   switch (cmd) {
   case TEST_INIT:
      info->name = "nack_no_packet_loss";
      info->category = "/res/res_rtp/";
      info->summary = "nack no packet loss unit test";
      info->description =
         "Tests sending packets with no packet loss and "
         "validates that the send buffer stores sent packets "
         "and the receive buffer is empty";
      return AST_TEST_NOT_RUN;
   case TEST_EXECUTE:
      break;
   }

   test_sched = ast_sched_context_create();

   if ((test_init_rtp_instances(&instance1, &instance2, test_sched, TEST_TYPE_NACK)) < 0) {
      ast_log(LOG_ERROR, "Failed to initialize test!\n");
      return AST_TEST_FAIL;
   }

   test_write_and_read_frames(instance1, instance2, 1000, 10);

   ast_test_validate(test, ast_rtp_instance_get_send_buffer_count(instance1) == 10,
      "Send buffer did not have the expected count of 10");

   ast_test_validate(test, ast_rtp_instance_get_recv_buffer_count(instance2) == 0,
      "Receive buffer did not have the expected count of 0");

   return AST_TEST_PASS;
}

AST_TEST_DEFINE(nack_nominal)
{
   RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_rtp_instance *, instance2, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_sched_context *, test_sched, NULL, ast_sched_context_destroy_wrapper);

   switch (cmd) {
   case TEST_INIT:
      info->name = "nack_nominal";
      info->category = "/res/res_rtp/";
      info->summary = "nack nominal unit test";
      info->description =
         "Tests sending packets with some packet loss and "
         "validates that a NACK request is sent on reaching "
         "the triggering amount of lost packets";
      return AST_TEST_NOT_RUN;
   case TEST_EXECUTE:
      break;
   }

   test_sched = ast_sched_context_create();

   if ((test_init_rtp_instances(&instance1, &instance2, test_sched, TEST_TYPE_NACK)) < 0) {
      ast_log(LOG_ERROR, "Failed to initialize test!\n");
      return AST_TEST_FAIL;
   }

   /* Start normally */
   test_write_and_read_frames(instance1, instance2, 1000, 10);

   /* Set the number of packets to drop when we send them next */
   ast_rtp_instance_drop_packets(instance2, 10);
   test_write_and_read_frames(instance1, instance2, 1010, 10);

   /* Send enough packets to reach the NACK trigger */
   test_write_and_read_frames(instance1, instance2, 1020, ast_rtp_instance_get_recv_buffer_max(instance2) / 2);

   /* This needs to be read as RTCP */
   test_read_frames(instance1, 1);

   /* We should have the missing packets to read now */
   test_read_frames(instance2, 10);

   ast_test_validate(test, ast_rtp_instance_get_recv_buffer_count(instance2) == 0,
      "Receive buffer did not have the expected count of 0");

   return AST_TEST_PASS;
}

AST_TEST_DEFINE(nack_overflow)
{
   RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_rtp_instance *, instance2, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_sched_context *, test_sched, NULL, ast_sched_context_destroy_wrapper);
   int max_packets;

   switch (cmd) {
   case TEST_INIT:
      info->name = "nack_overflow";
      info->category = "/res/res_rtp/";
      info->summary = "nack overflow unit test";
      info->description =
         "Tests that when the buffer hits its capacity, we "
         "queue all the packets we currently have stored";
      return AST_TEST_NOT_RUN;
   case TEST_EXECUTE:
      break;
   }

   test_sched = ast_sched_context_create();

   if ((test_init_rtp_instances(&instance1, &instance2, test_sched, TEST_TYPE_NACK)) < 0) {
      ast_log(LOG_ERROR, "Failed to initialize test!\n");
      return AST_TEST_FAIL;
   }

   /* Start normally */
   test_write_and_read_frames(instance1, instance2, 1000, 10);

   /* Send enough packets to fill the buffer */
   max_packets = ast_rtp_instance_get_recv_buffer_max(instance2);
   test_write_and_read_frames(instance1, instance2, 1020, max_packets);

   ast_test_validate(test, ast_rtp_instance_get_recv_buffer_count(instance2) == max_packets,
      "Receive buffer did not have the expected count of max buffer size");

   /* Send the packet that will overflow the buffer */
   test_write_and_read_frames(instance1, instance2, 1020 + max_packets, 1);

   ast_test_validate(test, ast_rtp_instance_get_recv_buffer_count(instance2) == 0,
      "Receive buffer did not have the expected count of 0");

   return AST_TEST_PASS;
}

AST_TEST_DEFINE(lost_packet_stats_nominal)
{
   RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_rtp_instance *, instance2, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_sched_context *, test_sched, NULL, ast_sched_context_destroy_wrapper);
   struct ast_rtp_instance_stats stats = { 0, };
   enum ast_rtp_instance_stat stat = AST_RTP_INSTANCE_STAT_ALL;

   switch (cmd) {
   case TEST_INIT:
      info->name = "lost_packet_stats_nominal";
      info->category = "/res/res_rtp/";
      info->summary = "lost packet stats nominal unit test";
      info->description =
         "Tests that when some packets are lost, we calculate that "
         "loss correctly when doing lost packet statistics";
      return AST_TEST_NOT_RUN;
   case TEST_EXECUTE:
      break;
   }

   test_sched = ast_sched_context_create();

   if ((test_init_rtp_instances(&instance1, &instance2, test_sched, TEST_TYPE_NONE)) < 0) {
      ast_log(LOG_ERROR, "Failed to initialize test!\n");
      return AST_TEST_FAIL;
   }

   /* Start normally */
   test_write_and_read_frames(instance1, instance2, 1000, 10);

   /* Send some more packets, but with a gap */
   test_write_and_read_frames(instance1, instance2, 1015, 5);

   /* Send a RR to calculate lost packet statistics. We should be missing 5 packets */
   ast_rtp_instance_queue_report(instance1);
   test_write_frames(instance2, 1000, 1);

   /* Check RTCP stats to see if we got the expected packet loss count */
   ast_rtp_instance_get_stats(instance2, &stats, stat);
   ast_test_validate(test, stats.rxploss == 5 && stats.local_minrxploss == 5 &&
      stats.local_maxrxploss == 5, "Condition of 5 lost packets was not met");

   /* Drop 3 before writing 5 more */
   test_write_and_read_frames(instance1, instance2, 1023, 5);

   ast_rtp_instance_queue_report(instance1);
   test_write_frames(instance2, 1001, 1);
   ast_rtp_instance_get_stats(instance2, &stats, stat);

   /* Should now be missing 8 total packets with a change in min */
   ast_test_validate(test, stats.rxploss == 8 && stats.local_minrxploss == 3 &&
      stats.local_maxrxploss == 5);

   /* Write 5 more with no gaps */
   test_write_and_read_frames(instance1, instance2, 1028, 5);

   ast_rtp_instance_queue_report(instance1);
   test_write_frames(instance2, 1002, 1);
   ast_rtp_instance_get_stats(instance2, &stats, stat);

   /* Should still only be missing 8 total packets */
   ast_test_validate(test, stats.rxploss == 8 && stats.local_minrxploss == 3 &&
      stats.local_maxrxploss == 5);

   /* Now drop 1, write another 5, drop 8, and then write 5 */
   test_write_and_read_frames(instance1, instance2, 1034, 5);
   test_write_and_read_frames(instance1, instance2, 1047, 5);

   ast_rtp_instance_queue_report(instance1);
   test_write_frames(instance2, 1003, 1);
   ast_rtp_instance_get_stats(instance2, &stats, stat);

   /* Now it should be missing 17 total packets, with a change in max */
   ast_test_validate(test, stats.rxploss == 17 && stats.local_minrxploss == 3 &&
      stats.local_maxrxploss == 9);

   return AST_TEST_PASS;
}

AST_TEST_DEFINE(remb_nominal)
{
   RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_rtp_instance *, instance2, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_sched_context *, test_sched, NULL, ast_sched_context_destroy_wrapper);
   RAII_VAR(struct ast_frame *, frame_in, NULL, ast_frfree);
   /* Use the structure softmix_remb_collector uses to store information for REMB */
   struct ast_rtp_rtcp_feedback feedback = {
      .fmt = AST_RTP_RTCP_FMT_REMB,
      .remb.br_exp = 0,
      .remb.br_mantissa = 1000,
   };
   struct ast_frame frame_out = {
      .frametype = AST_FRAME_RTCP,
      .subclass.integer = AST_RTP_RTCP_PSFB,
      .data.ptr = &feedback,
      .datalen = sizeof(feedback),
   };
   struct ast_rtp_rtcp_feedback *received_feedback;

   switch (cmd) {
   case TEST_INIT:
      info->name = "remb_nominal";
      info->category = "/res/res_rtp/";
      info->summary = "remb nominal unit test";
      info->description =
         "Tests sending and receiving a REMB packet";
      return AST_TEST_NOT_RUN;
   case TEST_EXECUTE:
      break;
   }

   test_sched = ast_sched_context_create();

   if ((test_init_rtp_instances(&instance1, &instance2, test_sched, TEST_TYPE_REMB)) < 0) {
      ast_log(LOG_ERROR, "Failed to initialize test!\n");
      return AST_TEST_FAIL;
   }

   /* The schedid must be 0 or greater, so let's do that now */
   ast_rtp_instance_set_schedid(instance1, 0);

   ast_rtp_instance_write(instance1, &frame_out);

   /* Verify the high level aspects of the frame */
   frame_in = ast_rtp_instance_read(instance2, 0);
   ast_test_validate(test, frame_in != NULL, "Did not receive a REMB frame");
   ast_test_validate(test, frame_in->frametype == AST_FRAME_RTCP,
      "REMB frame did not have the expected frametype");
   ast_test_validate(test, frame_in->subclass.integer == AST_RTP_RTCP_PSFB,
      "REMB frame did not have the expected subclass integer");

   /* Verify the actual REMB information itself */
   received_feedback = frame_in->data.ptr;
   ast_test_validate(test, received_feedback->fmt == AST_RTP_RTCP_FMT_REMB,
      "REMB frame did not have the expected feedback format");
   ast_test_validate(test, received_feedback->remb.br_exp == feedback.remb.br_exp,
      "REMB received exponent did not match sent exponent");
   ast_test_validate(test, received_feedback->remb.br_mantissa == feedback.remb.br_mantissa,
      "REMB received mantissa did not match sent mantissa");

   return AST_TEST_PASS;
}

AST_TEST_DEFINE(sr_rr_nominal)
{
   RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_rtp_instance *, instance2, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_sched_context *, test_sched, NULL, ast_sched_context_destroy_wrapper);
   RAII_VAR(struct ast_frame *, frame_in, NULL, ast_frfree);

   switch (cmd) {
   case TEST_INIT:
      info->name = "sr_rr_nominal";
      info->category = "/res/res_rtp/";
      info->summary = "SR/RR nominal unit test";
      info->description =
         "Tests sending SR/RR and receiving it; includes SDES";
      return AST_TEST_NOT_RUN;
   case TEST_EXECUTE:
      break;
   }

   test_sched = ast_sched_context_create();

   if ((test_init_rtp_instances(&instance1, &instance2, test_sched, TEST_TYPE_NONE)) < 0) {
      ast_log(LOG_ERROR, "Failed to initialize test!\n");
      return AST_TEST_FAIL;
   }

   test_write_and_read_frames(instance1, instance2, 1000, 10);

   /*
    * Set the send_report flag so we send a sender report instead of normal RTP. We
    * also need to ensure that SDES processed.
    */
   ast_rtp_instance_queue_report(instance1);
   test_write_frames(instance1, 1010, 1);

   frame_in = ast_rtp_instance_read(instance2, 0);
   ast_test_validate(test, frame_in->frametype == AST_FRAME_RTCP,
      "Sender report frame did not have the expected frametype");
   ast_test_validate(test, frame_in->subclass.integer == AST_RTP_RTCP_SR,
      "Sender report frame did not have the expected subclass integer");
   ast_test_validate(test, ast_rtp_instance_get_sdes_received(instance2) == 1,
      "SDES was never processed for sender report");

   ast_frfree(frame_in);

   /* Set the send_report flag so we send a receiver report instead of normal RTP */
   ast_rtp_instance_queue_report(instance1);
   test_write_frames(instance1, 1010, 1);

   frame_in = ast_rtp_instance_read(instance2, 0);
   ast_test_validate(test, frame_in->frametype == AST_FRAME_RTCP,
      "Receiver report frame did not have the expected frametype");
   ast_test_validate(test, frame_in->subclass.integer == AST_RTP_RTCP_RR,
      "Receiver report frame did not have the expected subclass integer");

   return AST_TEST_PASS;
}

AST_TEST_DEFINE(fir_nominal)
{
   RAII_VAR(struct ast_rtp_instance *, instance1, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_rtp_instance *, instance2, NULL, ast_rtp_instance_destroy);
   RAII_VAR(struct ast_sched_context *, test_sched, NULL, ast_sched_context_destroy_wrapper);
   RAII_VAR(struct ast_frame *, frame_in, NULL, ast_frfree);
   struct ast_frame frame_out = {
      .frametype = AST_FRAME_CONTROL,
      .subclass.integer = AST_CONTROL_VIDUPDATE,
   };

   switch (cmd) {
   case TEST_INIT:
      info->name = "fir_nominal";
      info->category = "/res/res_rtp/";
      info->summary = "fir nominal unit test";
      info->description =
         "Tests sending and receiving a FIR packet";
      return AST_TEST_NOT_RUN;
   case TEST_EXECUTE:
      break;
   }

   test_sched = ast_sched_context_create();

   if ((test_init_rtp_instances(&instance1, &instance2, test_sched, TEST_TYPE_NONE)) < 0) {
      ast_log(LOG_ERROR, "Failed to initialize test!\n");
      return AST_TEST_FAIL;
   }

   /* Send some packets to learn SSRC */
   test_write_and_read_frames(instance2, instance1, 1000, 10);

   /* The schedid must be 0 or greater, so let's do that now */
   ast_rtp_instance_set_schedid(instance1, 0);

   /*
    * This will not directly write a frame out, but cause Asterisk to see it as a FIR
    * request, which will then trigger rtp_write_rtcp_fir, which will send out the
    * appropriate packet.
    */
   ast_rtp_instance_write(instance1, &frame_out);

   /*
    * We only receive one frame, the FIR request. It won't have a subclass integer of
    * 206 (PSFB) because ast_rtcp_interpret sets it to 18 (AST_CONTROL_VIDUPDATE), so
    * check for that.
    */
   frame_in = ast_rtp_instance_read(instance2, 0);
   ast_test_validate(test, frame_in != NULL, "Did not receive a FIR frame");
   ast_test_validate(test, frame_in->frametype == AST_FRAME_CONTROL,
      "FIR frame did not have the expected frametype");
   ast_test_validate(test, frame_in->subclass.integer == AST_CONTROL_VIDUPDATE,
      "FIR frame did not have the expected subclass integer");

   return AST_TEST_PASS;
}

static int unload_module(void)
{
   AST_TEST_UNREGISTER(nack_no_packet_loss);
   AST_TEST_UNREGISTER(nack_nominal);
   AST_TEST_UNREGISTER(nack_overflow);
   AST_TEST_UNREGISTER(lost_packet_stats_nominal);
   AST_TEST_UNREGISTER(remb_nominal);
   AST_TEST_UNREGISTER(sr_rr_nominal);
   AST_TEST_UNREGISTER(fir_nominal);
   return 0;
}

static int load_module(void)
{
   AST_TEST_REGISTER(nack_no_packet_loss);
   AST_TEST_REGISTER(nack_nominal);
   AST_TEST_REGISTER(nack_overflow);
   AST_TEST_REGISTER(lost_packet_stats_nominal);
   AST_TEST_REGISTER(remb_nominal);
   AST_TEST_REGISTER(sr_rr_nominal);
   AST_TEST_REGISTER(fir_nominal);
   return AST_MODULE_LOAD_SUCCESS;
}

AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "RTP/RTCP test module");