net/timestamp_inject/timestamp_inject_example.cpp

/*
 *
 * Copyright 2021 Napatech A/S. All Rights Reserved.
 *
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 * versions of this file, is governed by the terms of the Napatech Software
 * license agreement under which this file was made available. If you do not
 * agree to the terms of the license do not install, copy, access or
 * otherwise use this file.
 *
 * 2. Under the Napatech Software license agreement you are granted a
 * limited, non-exclusive, non-assignable, copyright license to copy, modify
 * and distribute this file in conjunction with Napatech SmartNIC's and
 * similar hardware manufactured or supplied by Napatech A/S.
 *
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 * distribution, please see "NP-0405 Napatech Software license
 * agreement.pdf"
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/**
 * @example net/timestamp_inject/timestamp_inject_example.cpp
 * @section timestamp_inject_example_description Description
 *
 * INFO: This is an 4GA TX timestamp inject and FCS generation example.
 *
 * This source file is an example of how to control TX time stamp inject
 * and FCS generation per packet using dynamic descriptor 3.
 *
 * One bit in the TX packet descriptor is used to control
 * TX time stamp inject, i.e. if the packet descriptor bit is
 * 1 a TX time stamp will be inserted in the packet.
 *
 * Two bits in the TX packet descriptor is used to control
 * FCS generation, i.e.
 * 0: Insert good FCS,
 * 1: Insert bad FCS,
 * 2: Reserved
 * 3: Don't change FCS
 *
 * This example requires the following setting in ntservive.ini
 *
 * TimestampFormat = UNIX_NS
 *
 * TimestampInjectStaticOffset = 80
 *
 * TimestampInjectDynamicOffset = TSI_DYN_SOF
 *
 * PacketDescriptor = NT
 *
 * This program consists of a TX and RX part.
 *
 * The TX part will transmit 6 packets in a loop.
 * The number of loops is a command line option.
 * To start the TX part use the -t <txport> option.
 *
 * The six packets in a loop are based on the same
 * packet template. Time stamp inject and FCS generation
 * are then controlled per packet to be:
 *
 *     txPacket(hNetTx, NO_TS_INJECT, FCS_UNCHANGED);
 *
 *     txPacket(hNetTx, NO_TS_INJECT, FCS_GOOD);
 *
 *     txPacket(hNetTx, NO_TS_INJECT, FCS_BAD);
 *
 *     txPacket(hNetTx, TS_INJECT,    FCS_UNCHANGED);
 *
 *     txPacket(hNetTx, TS_INJECT,    FCS_GOOD);
 *
 *     txPacket(hNetTx, TS_INJECT,    FCS_BAD);
 *
 * The RX part will receive packets from one port.
 * It will check for the a TX time stamp in received
 * packets and - if present - calculate and print
 * the TX-to-RX latency.
 * The RX part also dumps the received packet.
 * To start the RX part use the -r <rxport> option.
 *
 * Example:
 *
 * timestamp_inject_example -t 0 -n 5 -r 1
 *
 * will transmit on port 0 and receive on port 1.
 * The transmitter will execute the loop 5 times,
 * i.e. 30 packets will be transmitted.
 *
 */
#include "nt.h"
#include <atomic>
#include <iostream>
#include <thread>
#include <unistd.h>
#include <signal.h>
// Intentional global
std::atomic<bool> running {true};
// The struct below represents the TX dynamic descriptor
// used by this application
//
// The struct is based on a copy of Dynamic descriptor 3
// It is modified with the location of the command bits
// for controlling L3/L4 checksum handling, time stamp
// inject handling and FCS handling.
//
// This example uses 12 bits of the color_hi field
// for these command bits. In other words - the
// normal color_hi:28 has been replaced by the
// 12 command bits and a color_hi_unused:16
//
// note: This example doesn't use the L3/L4 checksum
// command bits. See examples/net/checksum for an
// example of L3/L4 checksum control.
struct Dyn3_tx_descriptor {
  uint64_t capLength:14;
  uint64_t wireLength:14;
  uint64_t color_lo:14;
  uint64_t rxPort:6;
  uint64_t descrFormat:8;
  uint64_t descrLength:6;
  uint64_t tsColor:1;
  uint64_t ntDynDescr:1;
  uint64_t timestamp;
                                // Location of control bits in the packet descriptor:
  uint64_t frame_type:4;        // Frame type: 4 bits starting at bit offset 128
  uint64_t checksum_cmd:5;      // L3/L4 check sum command, 5 bits starting at bit offset 132
  uint64_t tsiCmd:1;            // Timestamp inject command, 1 bits starting at bit offset 137
  uint64_t fcsCmd:2;            // FCS command, 1 bits starting at bit offset 138
  uint64_t color_hi_unused:16;  // The remaing 16 unused bits of color_hi
  uint64_t offset0:10;
  uint64_t offset1:10;
};
void printDescriptor(NtPacketDescriptorType_e descrType)
{
  switch (descrType)
  {
    case NT_PACKET_DESCRIPTOR_TYPE_PCAP:
        printf("Descriptor type is PCAP.\n");
        break;
    case NT_PACKET_DESCRIPTOR_TYPE_NT:
        printf("Descriptor type is NT.\n");
        break;
    case NT_PACKET_DESCRIPTOR_TYPE_NT_EXTENDED:
        printf("Descriptor type is NT extended.\n");
        break;
    case NT_PACKET_DESCRIPTOR_TYPE_DYNAMIC:
        printf("Descriptor type is Dynamic\n");
        break;
    case NT_PACKET_DESCRIPTOR_TYPE_UNKNOWN:
    default:
        printf("Unknown descriptor type.\n");
        break;
  }
}
/*
  The packet reader thread is responsible for
  reading packets from a single RX stream
*/
class PacketReaderThread
{
public:
  uint64_t rxPort;
  uint32_t streamId;
  std::thread thr;
  PacketReaderThread(uint64_t port) : rxPort(port) {
    streamId = (uint32_t) port;
    printf("Created PacketReaderThread, port=%lu, stream=%u\n", rxPort, streamId);
  }
  void processPackets(void) {
    NtNetStreamRx_t hNetRx = NULL;           // Handle to the RX stream
    NtNetBuf_t hNetBuf;                      // Net buffer container.
    char errorBuffer[NT_ERRBUF_SIZE];
    int status;
    status =  NT_NetRxOpen(&hNetRx, "PacketReader", NT_NET_INTERFACE_PACKET, streamId, -1);
    if (status != 0) {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      printf("NT_NetRxOpen() failed: %s\n", errorBuffer);
      running = false;
      return;
    }
    printf("Receiving packets on stream %u\n", streamId);
    while (running)
    {
      if ((status = NT_NetRxGetNextPacket(hNetRx, &hNetBuf, 100)) == NT_SUCCESS)
      {
        printf("-------------------------------------------------\n");
        printf("Packet received:\n");
        NtPacketDescriptorType_e descrType = NT_NET_GET_PKT_DESCRIPTOR_TYPE(hNetBuf);
        printDescriptor(descrType);
        if (descrType != NT_PACKET_DESCRIPTOR_TYPE_NT)
        {
          printf("Error: RX descriptor expected to be NT_PACKET_DESCRIPTOR_TYPE_NT\n");
          printf("       Shutting down...\n");
          running = false;
          break;
        }
        uint64_t captureLength = NT_NET_GET_PKT_CAP_LENGTH(hNetBuf);
        if (captureLength < (16 + 80 + 2 + 8))  // Descriptor + Timestamp Inject Static Offset + 2 byte compensation + 8 byte Time stamp
        {
          printf("Packet is too small. Can't extract time stamp\n");
        }
        else
        {
          unsigned char * data = (unsigned char *) NT_NET_GET_PKT_L2_PTR(hNetBuf);
          uint64_t txTime = *((uint64_t*)(data + 80 + 2));
          if (txTime == 0)
          {
            printf("No TX time stamp in packet.\n");
          }
          else
          {
            uint64_t rxTime = NT_NET_GET_PKT_TIMESTAMP(hNetBuf);
            printf("txTime=%lu, rxTime=%lu, latency=%lu\n", txTime, rxTime, rxTime - txTime);
          }
          // Dump packet
          uint64_t wireLength = NT_NET_GET_PKT_WIRE_LENGTH(hNetBuf);
          for (uint64_t g = 0; g < wireLength; ++g)
          {
            if ((g % 16) == 0) printf("\n");
            printf("%02X ", *(data + g));
          }
          printf("\n");
        }
      }
      else if ((status != NT_STATUS_TIMEOUT) && (status != NT_STATUS_TRYAGAIN))
      {
        NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
        printf("NT_NetRxGet() failed: %s\n", errorBuffer);
        running = false;
        break;
      }
    }
    NT_NetRxClose(hNetRx);
  }
  void run(void) {
    thr = std::thread(&PacketReaderThread::processPackets, this);
  }
  void join(void) {
    if (thr.joinable())
    {
      thr.join();
    }
  }
};
// Packet template: Ethernet, IPv4, TCP
const unsigned char examplePacket[] =
{
    0x94, 0xC6, 0x91, 0x1C, 0x68, 0x1D, 0x94, 0xC6, 0x91, 0x1C, 0x68, 0xC3, 0x08, 0x00, 0x45, 0x00,
    0x00, 0x78, 0x00, 0x01, 0x00, 0x00, 0x40, 0x06, 0xB5, 0xCF, 0xC0, 0xA8, 0x00, 0x02, 0x01, 0x02,
    0x03, 0x04, 0x00, 0x14, 0x00, 0x50, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x50, 0x02,
    0x20, 0x00, 0x42, 0xF7, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/*
  The packet transmitter thread is responsible for
  transmitting on a single port.
  The packets will have different combinations
  of time stamp inject and FCS calculation
  via command bits in the TX packet decriptor
*/
class PacketTransmitterThread
{
public:
  uint64_t transmittedPackets {0};
  uint32_t txPort;
  int64_t txLoops;
  std::thread thr;
  // Time stamp inject command bit values
  const unsigned char NO_TS_INJECT  = 0;
  const unsigned char TS_INJECT     = 1;
  // FCS command bits values
  const unsigned char FCS_GOOD      = 0;
  const unsigned char FCS_BAD       = 1;
  const unsigned char FCS_RESERVED  = 2;
  const unsigned char FCS_UNCHANGED = 3;
  PacketTransmitterThread(uint64_t port, int64_t loops) : txPort((uint32_t)port), txLoops(loops) {
    printf("Created PacketTransmitterThread port=%u\n", txPort);
  }
  void run(void) {
    thr = std::thread(&PacketTransmitterThread::transmitPackets, this);
  }
  void join(void) {
    if (thr.joinable())
    {
      thr.join();
    }
  }
private:
  void txPacket(NtNetStreamTx_t hNetTx, unsigned char tsi, unsigned char fcs) {
    uint32_t sleep_time = 1000000;
    NtNetBuf_t hNetBufTx;           // Net buffer container. Used when getting a transmit buffer
    int status;
    char errorBuffer[NT_ERRBUF_SIZE];
    const unsigned char * pData = examplePacket;
    size_t pktSize = sizeof examplePacket;
    if ((status = NT_NetTxGet(hNetTx, &hNetBufTx, txPort, pktSize, NT_NETTX_PACKET_OPTION_DYN, 100))  != NT_SUCCESS)
    {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxGet() failed: %s\n", errorBuffer);
      running = false;
      return;
    }
    //
    memcpy(NT_NET_GET_PKT_L2_PTR(hNetBufTx), pData, pktSize);
    auto packet_ptr = NT_NET_GET_PKT_DESCR_PTR_DYN3(hNetBufTx);
    auto overlay_ptr = reinterpret_cast<Dyn3_tx_descriptor*>(packet_ptr);
    packet_ptr->offset0 = 14;      // Point to start of Layer 3, i.e. set to size of Ethernet header
    packet_ptr->offset1 = 34;      // Point to start of Layer 4, i.e. set to size of Ethernet header + IPv4 header with no options
    overlay_ptr->frame_type = 0x4; // IPv4 packet carrying TCP
    overlay_ptr->checksum_cmd = 0; // L3/L4 checksum_command, set to "do nothing"
    overlay_ptr->tsiCmd = tsi & 1; // Set the time stamp inject command bits
    overlay_ptr->fcsCmd = fcs & 3; // Set the FCS command bits
    // Release the TX buffer and the packet will be transmitted
    if ((status = NT_NetTxRelease(hNetTx, hNetBufTx)) != NT_SUCCESS)
    {
      // Get the status code as text
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxRelease() failed: %s\n", errorBuffer);
      running = false;
      return;
    }
    ++transmittedPackets;
    if (sleep_time)
    {
        usleep(sleep_time);
    }
  }
  void transmitPackets(void) {
    char errorBuffer[NT_ERRBUF_SIZE];
    int status;
    NtNetStreamTx_t hNetTx;         // Handle to the TX stream
    printf("============================================\n");
    printf("Transmitter configuration\n");
    printf("============================================\n");
    printf("TX port                     : %u\n", txPort);
    printf("============================================\n");
    NtNetTxAttr_t txAttr;
    NT_NetTxOpenAttrInit(&txAttr);
    NT_NetTxOpenAttrSetName(&txAttr, "Time stamp Inject and FCS example");
    NT_NetTxOpenAttrSetPortMask(&txAttr, static_cast<uint64_t>(1U) << txPort);
    NT_NetTxOpenAttrSetMinHostbufferSize(&txAttr, 0);
    NT_NetTxOpenAttrSetDescriptorMode(&txAttr, NT_NETTX_DESCRIPTOR_MODE_DYN3);
    // Set the position of the various descriptor command
    // in accordance with struct Dyn3_tx_descriptor
    status = NT_NetTxOpenAttrSetDescriptorPosFrameType(&txAttr, true, 128);
    if (status != NT_SUCCESS)
    {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxOpenAttrSetDescriptorPosFrameType failed: %s\n", errorBuffer);
      exit(1);
    }
    status = NT_NetTxOpenAttrSetDescriptorPosChecksumCmd(&txAttr, true, 132);
    if (status != NT_SUCCESS)
    {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxOpenAttrSetDescriptorPosChecksumCmd failed: %s\n", errorBuffer);
      exit(1);
    }
    status = NT_NetTxOpenAttrSetTxtDescriptorPosTimestampInject(&txAttr,  true, 137);
    if (status != NT_SUCCESS)
    {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxOpenAttrSetTxtDescriptorPosTimestampInjectCmd failed: %s\n", errorBuffer);
      exit(1);
    }
    status = NT_NetTxOpenAttrSetTxtDescriptorPosFcs(&txAttr,  true, 138);
    if (status != NT_SUCCESS)
    {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxOpenAttrSetTxtDescriptorPosFcs failed: %s\n", errorBuffer);
      exit(1);
    }
    // Open the TX network stream
    status = NT_NetTxOpen_Attr(&hNetTx, &txAttr);
    if (status != NT_SUCCESS) {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxOpen() failed: %s\n", errorBuffer);
      return;
    }
    // Main TX loop
    while (running && txLoops != 0)
    {
      if (txLoops > 0) --txLoops;
      // Transmit 6 packets
      txPacket(hNetTx, NO_TS_INJECT, FCS_UNCHANGED);
      txPacket(hNetTx, NO_TS_INJECT, FCS_GOOD);
      txPacket(hNetTx, NO_TS_INJECT, FCS_BAD);
      txPacket(hNetTx, TS_INJECT,    FCS_UNCHANGED);
      txPacket(hNetTx, TS_INJECT,    FCS_GOOD);
      txPacket(hNetTx, TS_INJECT,    FCS_BAD);
    }
    printf("Packets transmitted %lu\n ", transmittedPackets);
    printf("Shutting down TX\n");
    if ((status = NT_NetTxClose(hNetTx)) != NT_SUCCESS)
    {
      NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
      fprintf(stderr, "NT_NetTxClose() failed: %s\n", errorBuffer);
      return;
    }
    running = false;
  }
};
static void sighandler(int /*sig*/)
{
  running = false;
}
void printError(int status, const char* formatstr)
{
  char errorBuffer[NT_ERRBUF_SIZE];
  // Retrieve the textual description of the status code
  NT_ExplainError(status, errorBuffer, (uint32_t)(sizeof(errorBuffer)-1));
  // Log to stderr
  fprintf(stderr, formatstr, errorBuffer);
}
// Setup RX filter
void applyNtpl(uint64_t rxPort)
{
  NtConfigStream_t hCfgStream;
  char ntplStr[400];
  int status;
  snprintf(ntplStr, 400, "assign[streamid=%lu] = Port==%lu", rxPort, rxPort);
  // Open a config stream to assign a filter to a stream ID.
  if ((status = NT_ConfigOpen(&hCfgStream, "flowtest")) != NT_SUCCESS) {
    printError(status, "NT_ConfigOpen() failed: %s\n");
    exit(1);
  }
  printf("\nDoing NTPL:\n");
  NtNtplInfo_t ntplInfo;
  printf("%s\n\n", ntplStr);
  if ((status = NT_NTPL(hCfgStream, ntplStr, &ntplInfo, NT_NTPL_PARSER_VALIDATE_NORMAL)) != NT_SUCCESS) {
    printError(status, "NT_NTPL() failed: %s\n");
    exit(1);
  }
  NT_ConfigClose(hCfgStream);
}
bool featuresAvailable(uint64_t txPort)
{
  int status;
  NtInfoStream_t hInfo;
  char errorBuffer[NT_ERRBUF_SIZE];
  NtInfo_t infoRead;
  // Open the infostream.
  if ((status = NT_InfoOpen(&hInfo, "tsi")) != NT_SUCCESS) {
    NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
    fprintf(stderr, "NT_InfoOpen() failed: %s\n", errorBuffer);
    return false;
  }
  // Check whether or not Time stamp inject is supported on the defined port
  infoRead.cmd = NT_INFO_CMD_READ_PORT_V9;
  infoRead.u.port_v9.portNo = 0xFF & txPort;
  if ((status = NT_InfoRead(hInfo, &infoRead)) != NT_SUCCESS) {
    NT_ExplainError(status, errorBuffer, sizeof(errorBuffer));
    fprintf(stderr, "NT_InfoRead() failed: %s\n", errorBuffer);
    NT_InfoClose(hInfo);
    return false;
  }
  NT_InfoClose(hInfo);
  if (
      ((infoRead.u.port_v9.data.capabilities.featureMask & NT_PORT_FEATURE_INJECT_TX_TS) == 0) ||
      ((infoRead.u.port_v9.data.capabilities.featureMask & NT_PORT_FEATURE_FCS_TX_CHECKSUM_CALC) == 0) ||
      ((infoRead.u.port_v9.data.capabilities.featureMask & NT_PORT_FEATURE_IPV4_TX_CHECKSUM_CALC) == 0) ||
      ((infoRead.u.port_v9.data.capabilities.featureMask & NT_PORT_FEATURE_UDP_TX_CHECKSUM_CALC) == 0) ||
      ((infoRead.u.port_v9.data.capabilities.featureMask & NT_PORT_FEATURE_TCP_TX_CHECKSUM_CALC) == 0)
      )
  {
    return false;
  }
  return true;
}
static void usage(const char *argv0)
{
  fprintf(stderr, "\n");
  fprintf(stderr, "Usage: %s [options]\n", argv0);
  fprintf(stderr, "\n");
  fprintf(stderr, "This program is an example of how to control TX time stamp inject\n");
  fprintf(stderr, "and FCS generation per packet using dynamic descriptor 3.\n");
  fprintf(stderr, "\n");
  fprintf(stderr, " Options:\n"
          "  -r <rx port>      : RX port.\n"
          "  -t <tx port>      : TX port.\n"
          "  -n <tx loops>     : Number of TX loops\n"
          "  -h                : Print help message\n");
  fprintf(stderr, "\n");
}
int main(int argc, char **argv)
{
   int opt;
  int64_t txLoops = -1;
  uint64_t txPort = 0;
  uint64_t rxPort = 0;
  uint64_t txActive = false;
  uint64_t rxActive = false;
  PacketReaderThread* rxThread = nullptr;
  PacketTransmitterThread* txThread = nullptr;
  char *endptr;
  while ((opt = getopt(argc, argv, "n:t:r:")) != -1) {
    switch (opt) {
      case 'r':
          rxPort = strtoul(optarg, &endptr, 10);
          rxActive = true;
          if (*optarg == '\0' || *endptr != '\0') {
            fprintf(stderr, "Could not parse RX port, i.e. -r option\n");
            exit(1);
          }
          break;
      case 't':
          txPort = strtoul(optarg, &endptr, 10);
          txActive = true;
          if (*optarg == '\0' || *endptr != '\0') {
            fprintf(stderr, "Could not parse TX port, i.e. -t option\n");
            exit(1);
          }
          break;
      case 'n':
          txLoops = strtol(optarg, &endptr, 10);
          if (*optarg == '\0' || *endptr != '\0') {
            fprintf(stderr, "Could not parse number of TX loops, , i.e. -n option\n");
            exit(1);
          }
          break;
      case 'h':
          usage(argv[0]);
          exit(0);
          break;
      default:
          usage(argv[0]);
          exit(1);
    }
  }
  signal(SIGINT, sighandler);
  NT_Init(NTAPI_VERSION);
  if (!featuresAvailable(txPort))
  {
    printf("\nRequired Test&Measurement features not supported on port %lu\n", txPort);
    return 0;
  }
  if (txActive)
  {
    txThread = new PacketTransmitterThread(txPort, txLoops);
  }
  if (rxActive)
  {
    applyNtpl(rxPort);
    rxThread = new PacketReaderThread(rxPort);
  }
  if (rxThread == nullptr && txThread == nullptr)
  {
    printf("\nUse at least one of the options -t, -r\n");
    return 0;
  }
  if (rxThread != nullptr)
  {
    rxThread->run();
  }
  usleep(1000000);
  if (txThread != nullptr)
  {
    txThread->run();
  }
  printf("Threads started. Press CTRL-C to terminate program.\n");
  while (running)
  {
    usleep(1000);
  };
  if (txThread != nullptr)
  {
    txThread->join();
    delete txThread;
    if (rxThread != nullptr && running)
    {
      printf("TX thread stopped. Use CTRL-C to terminate RX thread\n");
    }
  }
  if (rxThread != nullptr)
  {
    rxThread->join();
    delete rxThread;
  }
  NT_Done();
  return 0;
}