ping.c

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/*
 * Copyright (c) 2016 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <vnet/ip/ping.h>
#include <vnet/fib/ip6_fib.h>
#include <vnet/fib/ip4_fib.h>
#include <vnet/fib/fib_entry.h>

/**
 * @file
 * @brief IPv4 and IPv6 ICMP Ping.
 *
 * This file contains code to suppport IPv4 or IPv6 ICMP ECHO_REQUEST to
 * network hosts.
 *
 */


u8 *
format_icmp4_input_trace (u8 * s, va_list * va)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
  icmp4_input_trace_t *t = va_arg (*va, icmp4_input_trace_t *);

  s = format (s, "%U",
              format_ip4_header, t->packet_data, sizeof (t->packet_data));

  return s;
}

/*
 * If we can find the ping run by an ICMP ID, then we send the signal
 * to the CLI process referenced by that ping run, alongside with
 * a freshly made copy of the packet.
 * I opted for a packet copy to keep the main packet processing path
 * the same as for all the other nodes.
 *
 */

static void
signal_ip46_icmp_reply_event (vlib_main_t * vm,
                              u8 event_type, vlib_buffer_t * b0)
{
  ping_main_t *pm = &ping_main;
  u16 net_icmp_id = 0;
  u32 bi0_copy = 0;

  switch (event_type)
    {
    case PING_RESPONSE_IP4:
      {
        icmp4_echo_request_header_t *h0 = vlib_buffer_get_current (b0);
        net_icmp_id = h0->icmp_echo.id;
      }
      break;
    case PING_RESPONSE_IP6:
      {
        icmp6_echo_request_header_t *h0 = vlib_buffer_get_current (b0);
        net_icmp_id = h0->icmp_echo.id;
      }
      break;
    default:
      return;
    }

  uword *p = hash_get (pm->ping_run_by_icmp_id,
                       clib_net_to_host_u16 (net_icmp_id));
  if (!p)
    return;

  ping_run_t *pr = vec_elt_at_index (pm->ping_runs, p[0]);
  if (vlib_buffer_alloc (vm, &bi0_copy, 1) == 1)
    {
      void *dst = vlib_buffer_get_current (vlib_get_buffer (vm, bi0_copy));
      clib_memcpy (dst, vlib_buffer_get_current (b0), b0->current_length);
    }
  /* If buffer_alloc failed, bi0_copy == 0 - just signaling an event. */

  vlib_process_signal_event (vm, pr->cli_process_id, event_type, bi0_copy);
}

/*
 * Process ICMPv6 echo replies
 */
static uword
ip6_icmp_echo_reply_node_fn (vlib_main_t * vm,
                             vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  u32 n_left_from, *from;

  from = vlib_frame_vector_args (frame);        /* array of buffer indices */
  n_left_from = frame->n_vectors;       /* number of buffer indices */

  while (n_left_from > 0)
    {
      u32 bi0;
      vlib_buffer_t *b0;
      u32 next0;

      bi0 = from[0];
      b0 = vlib_get_buffer (vm, bi0);

      signal_ip46_icmp_reply_event (vm, PING_RESPONSE_IP6, b0);

      /* push this pkt to the next graph node, always error-drop */
      next0 = ICMP6_ECHO_REPLY_NEXT_NORMAL;
      vlib_set_next_frame_buffer (vm, node, next0, bi0);

      from += 1;
      n_left_from -= 1;
    }

  return frame->n_vectors;
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (ip6_icmp_echo_reply_node, static) =
{
  .function = ip6_icmp_echo_reply_node_fn,
  .name = "ip6-icmp-echo-reply",
  .vector_size = sizeof (u32),
  .format_trace = format_icmp6_input_trace,
  .n_next_nodes = ICMP6_ECHO_REPLY_N_NEXT,
  .next_nodes = {
    [ICMP6_ECHO_REPLY_NEXT_NORMAL] = "error-drop",
  },
};
/* *INDENT-ON* */

/*
 * Process ICMPv4 echo replies
 */
static uword
ip4_icmp_echo_reply_node_fn (vlib_main_t * vm,
                             vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  u32 n_left_from, *from;

  from = vlib_frame_vector_args (frame);        /* array of buffer indices */
  n_left_from = frame->n_vectors;       /* number of buffer indices */

  while (n_left_from > 0)
    {
      u32 bi0;
      vlib_buffer_t *b0;
      u32 next0;

      bi0 = from[0];
      b0 = vlib_get_buffer (vm, bi0);

      /* push this pkt to the next graph node, always error-drop */
      signal_ip46_icmp_reply_event (vm, PING_RESPONSE_IP4, b0);

      next0 = ICMP4_ECHO_REPLY_NEXT_NORMAL;
      vlib_set_next_frame_buffer (vm, node, next0, bi0);

      from += 1;
      n_left_from -= 1;
    }

  return frame->n_vectors;
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (ip4_icmp_echo_reply_node, static) =
{
  .function = ip4_icmp_echo_reply_node_fn,
  .name = "ip4-icmp-echo-reply",
  .vector_size = sizeof (u32),
  .format_trace = format_icmp4_input_trace,
  .n_next_nodes = ICMP4_ECHO_REPLY_N_NEXT,
  .next_nodes = {
    [ICMP4_ECHO_REPLY_NEXT_NORMAL] = "error-drop",
  },
};
/* *INDENT-ON* */

char *ip6_lookup_next_nodes[] = IP6_LOOKUP_NEXT_NODES;
char *ip4_lookup_next_nodes[] = IP4_LOOKUP_NEXT_NODES;

/* get first interface address */
static ip6_address_t *
ip6_interface_first_address (ip6_main_t * im, u32 sw_if_index)
{
  ip_lookup_main_t *lm = &im->lookup_main;
  ip_interface_address_t *ia = 0;
  ip6_address_t *result = 0;

  foreach_ip_interface_address (lm, ia, sw_if_index,
                                1 /* honor unnumbered */ ,
                                (
                                  {
                                  ip6_address_t * a =
                                  ip_interface_address_get_address (lm, ia);
                                  result = a;
                                  break;
                                  }
                                ));
  return result;
}

/* Fill in the ICMP ECHO structure, return the safety-checked and possibly shrunk data_len */
static u16
init_icmp46_echo_request (icmp46_echo_request_t * icmp46_echo,
                          u16 seq_host, u16 id_host, u16 data_len)
{
  int i;
  icmp46_echo->seq = clib_host_to_net_u16 (seq_host);
  icmp46_echo->id = clib_host_to_net_u16 (id_host);

  for (i = 0; i < sizeof (icmp46_echo->data); i++)
    {
      icmp46_echo->data[i] = i % 256;
    }

  if (data_len > sizeof (icmp46_echo_request_t))
    {
      data_len = sizeof (icmp46_echo_request_t);
    }
  return data_len;
}

/*
 * Given adj index, return sw_if_index, possibly overwritten
 * by a parameter. There is mostly debug outputs here,
 * but it turned out handy to have these.
 */

static u32
adj_index_to_sw_if_index (vlib_main_t * vm, ip_lookup_main_t * lm,
                          char *lookup_next_nodes[], u32 adj_index0,
                          u32 sw_if_index, u8 verbose)
{
  ip_adjacency_t *adj0 = ip_get_adjacency (lm, adj_index0);
  u32 sw_if_index0 = adj0->rewrite_header.sw_if_index;
  if (verbose)
    {
      vlib_cli_output (vm, "Adjacency index: %u, sw_if_index: %u\n",
                       adj_index0, sw_if_index0);
      vlib_cli_output (vm, "Adj: %s\n",
                       lookup_next_nodes[adj0->lookup_next_index]);
      vlib_cli_output (vm, "Adj Interface: %d\n", adj0->if_address_index);
    }

  if (~0 != sw_if_index)
    {
      sw_if_index0 = sw_if_index;
      if (verbose)
        {
          vlib_cli_output (vm, "Forced set interface: %d\n", sw_if_index0);
        }
    }
  return sw_if_index0;
}

static send_ip46_ping_result_t
send_ip6_ping (vlib_main_t * vm, ip6_main_t * im, ip6_address_t * pa6,
               u32 sw_if_index, u16 seq_host, u16 id_host, u16 data_len,
               u8 verbose)
{
  icmp6_echo_request_header_t *h0;
  u32 bi0 = 0;
  u32 sw_if_index0;
  ip_lookup_main_t *lm = &im->lookup_main;
  int bogus_length = 0;
  u32 adj_index0;
  vlib_buffer_t *p0;
  vlib_frame_t *f;
  u32 *to_next;
  u32 fib_index0;

  if (vlib_buffer_alloc (vm, &bi0, 1) != 1)
    return SEND_PING_ALLOC_FAIL;

  p0 = vlib_get_buffer (vm, bi0);

  /* Determine sw_if_index0 of source intf, may be force-set via sw_if_index. */
  vnet_buffer (p0)->sw_if_index[VLIB_RX] = 0;
  vnet_buffer (p0)->sw_if_index[VLIB_TX] = ~0;  /* use interface VRF */
  fib_index0 = 0;
  adj_index0 = fib_entry_get_adj(ip6_fib_table_lookup(fib_index0, pa6, 128));

  if (ADJ_INDEX_INVALID == adj_index0)
    {
      vlib_buffer_free (vm, &bi0, 1);
      return SEND_PING_NO_INTERFACE;
    }

  sw_if_index0 =
    adj_index_to_sw_if_index (vm, lm, ip6_lookup_next_nodes, adj_index0,
                              sw_if_index, verbose);
  if ((~0 == sw_if_index0) && (~0 == sw_if_index))
    {
      vlib_buffer_free (vm, &bi0, 1);
      return SEND_PING_NO_INTERFACE;
    }
  vnet_buffer (p0)->sw_if_index[VLIB_RX] = sw_if_index0;

  h0 = vlib_buffer_get_current (p0);

  /* Fill in ip6 header fields */
  h0->ip6.ip_version_traffic_class_and_flow_label =
    clib_host_to_net_u32 (0x6 << 28);
  h0->ip6.payload_length = 0;   /* Set below */
  h0->ip6.protocol = IP_PROTOCOL_ICMP6;
  h0->ip6.hop_limit = 255;
  h0->ip6.dst_address = *pa6;
  h0->ip6.src_address = *pa6;

  /* Fill in the correct source now */
  ip6_address_t *a = ip6_interface_first_address (im, sw_if_index0);
  h0->ip6.src_address = a[0];

  /* Fill in icmp fields */
  h0->icmp.type = ICMP6_echo_request;
  h0->icmp.code = 0;
  h0->icmp.checksum = 0;

  data_len =
    init_icmp46_echo_request (&h0->icmp_echo, seq_host, id_host, data_len);
  h0->icmp_echo.time_sent = vlib_time_now (vm);

  /* Fix up the lengths */
  h0->ip6.payload_length =
    clib_host_to_net_u16 (data_len + sizeof (icmp46_header_t));

  p0->current_length = clib_net_to_host_u16 (h0->ip6.payload_length) +
    STRUCT_OFFSET_OF (icmp6_echo_request_header_t, icmp);

  /* Calculate the ICMP checksum */
  h0->icmp.checksum = 0;
  h0->icmp.checksum =
    ip6_tcp_udp_icmp_compute_checksum (vm, 0, &h0->ip6, &bogus_length);

  /* Enqueue the packet right now */
  f = vlib_get_frame_to_node (vm, ip6_lookup_node.index);
  to_next = vlib_frame_vector_args (f);
  to_next[0] = bi0;
  f->n_vectors = 1;
  vlib_put_frame_to_node (vm, ip6_lookup_node.index, f);

  return SEND_PING_OK;
}

static send_ip46_ping_result_t
send_ip4_ping (vlib_main_t * vm,
               ip4_main_t * im,
               ip4_address_t * pa4,
               u32 sw_if_index,
               u16 seq_host, u16 id_host, u16 data_len, u8 verbose)
{
  icmp4_echo_request_header_t *h0;
  u32 bi0 = 0;
  u32 sw_if_index0;
  ip_lookup_main_t *lm = &im->lookup_main;
  u32 adj_index0;
  vlib_buffer_t *p0;
  vlib_frame_t *f;
  u32 *to_next;
  u32 fib_index0;
  u32 if_add_index0;

  if (vlib_buffer_alloc (vm, &bi0, 1) != 1)
    return SEND_PING_ALLOC_FAIL;

  p0 = vlib_get_buffer (vm, bi0);

  /* Determine sw_if_index0 of the source intf, may be force-set via sw_if_index.  */
  vnet_buffer (p0)->sw_if_index[VLIB_RX] = 0;
  vnet_buffer (p0)->sw_if_index[VLIB_TX] = ~0;  /* use interface VRF */
  fib_index0 = 0;
  adj_index0 = fib_entry_get_adj(ip4_fib_table_lookup(
                                     ip4_fib_get(fib_index0), pa4, 32));

  if (ADJ_INDEX_INVALID == adj_index0)
    {
      vlib_buffer_free (vm, &bi0, 1);
      return SEND_PING_NO_INTERFACE;
    }

  sw_if_index0 =
    adj_index_to_sw_if_index (vm, lm, ip4_lookup_next_nodes, adj_index0,
                              sw_if_index, verbose);
  if ((~0 == sw_if_index0) && (~0 == sw_if_index))
    {
      vlib_buffer_free (vm, &bi0, 1);
      return SEND_PING_NO_INTERFACE;
    }
  vnet_buffer (p0)->sw_if_index[VLIB_RX] = sw_if_index0;

  h0 = vlib_buffer_get_current (p0);

  /* Fill in ip4 header fields */
  h0->ip4.checksum = 0;
  h0->ip4.ip_version_and_header_length = 0x45;
  h0->ip4.tos = 0;
  h0->ip4.length = 0;           /* Set below */
  h0->ip4.fragment_id = 0;
  h0->ip4.flags_and_fragment_offset = 0;
  h0->ip4.ttl = 0xff;
  h0->ip4.protocol = IP_PROTOCOL_ICMP;
  h0->ip4.dst_address = *pa4;
  h0->ip4.src_address = *pa4;

  /* Fill in the correct source now */
  if_add_index0 = lm->if_address_pool_index_by_sw_if_index[sw_if_index0];
  if (PREDICT_TRUE (if_add_index0 != ~0))
    {
      ip_interface_address_t *if_add =
        pool_elt_at_index (lm->if_address_pool, if_add_index0);
      ip4_address_t *if_ip = ip_interface_address_get_address (lm, if_add);
      h0->ip4.src_address = *if_ip;
      if (verbose)
        {
          vlib_cli_output (vm, "Source address: %U",
                           format_ip4_address, &h0->ip4.src_address);
        }
    }

  /* Fill in icmp fields */
  h0->icmp.type = ICMP4_echo_request;
  h0->icmp.code = 0;
  h0->icmp.checksum = 0;

  data_len =
    init_icmp46_echo_request (&h0->icmp_echo, seq_host, id_host, data_len);
  h0->icmp_echo.time_sent = vlib_time_now (vm);

  /* Fix up the lengths */
  h0->ip4.length =
    clib_host_to_net_u16 (data_len + sizeof (icmp46_header_t) +
                          sizeof (ip4_header_t));

  p0->current_length = clib_net_to_host_u16 (h0->ip4.length);

  /* Calculate the IP and ICMP checksums */
  h0->ip4.checksum = ip4_header_checksum (&(h0->ip4));
  h0->icmp.checksum =
    ~ip_csum_fold (ip_incremental_checksum (0, &(h0->icmp),
                    p0->current_length - sizeof (ip4_header_t)));

  /* Enqueue the packet right now */
  f = vlib_get_frame_to_node (vm, ip4_lookup_node.index);
  to_next = vlib_frame_vector_args (f);
  to_next[0] = bi0;
  f->n_vectors = 1;
  vlib_put_frame_to_node (vm, ip4_lookup_node.index, f);

  return SEND_PING_OK;
}


static void
print_ip6_icmp_reply (vlib_main_t * vm, u32 bi0)
{
  vlib_buffer_t *b0 = vlib_get_buffer (vm,
                                       bi0);
  icmp6_echo_request_header_t *h0 = vlib_buffer_get_current (b0);
  f64 rtt = vlib_time_now (vm) - h0->icmp_echo.time_sent;

  vlib_cli_output (vm,
                   "%d bytes from %U: icmp_seq=%d ttl=%d time=%.4f ms",
                   clib_host_to_net_u16 (h0->ip6.payload_length),
                   format_ip6_address,
                   &h0->ip6.src_address,
                   clib_host_to_net_u16 (h0->icmp_echo.seq),
                   h0->ip6.hop_limit, rtt * 1000.0);
}

static void
print_ip4_icmp_reply (vlib_main_t * vm, u32 bi0)
{
  vlib_buffer_t *b0 = vlib_get_buffer (vm,
                                       bi0);
  icmp4_echo_request_header_t *h0 = vlib_buffer_get_current (b0);
  f64 rtt = vlib_time_now (vm) - h0->icmp_echo.time_sent;
  u32 rcvd_icmp_len =
    clib_host_to_net_u16 (h0->ip4.length) -
    (4 * (0xF & h0->ip4.ip_version_and_header_length));

  vlib_cli_output (vm,
                   "%d bytes from %U: icmp_seq=%d ttl=%d time=%.4f ms",
                   rcvd_icmp_len,
                   format_ip4_address,
                   &h0->ip4.src_address,
                   clib_host_to_net_u16 (h0->icmp_echo.seq),
                   h0->ip4.ttl, rtt * 1000.0);
}


/*
 * Perform the ping run with the given parameters in the current CLI process.
 * Depending on whether pa4 or pa6 is set, runs IPv4 or IPv6 ping.
 * The amusing side effect is of course if both are set, then both pings are sent.
 * This behavior can be used to ping a dualstack host over IPv4 and IPv6 at once.
 */

static void
run_ping_ip46_address (vlib_main_t * vm, ip4_address_t * pa4,
                       ip6_address_t * pa6, u32 sw_if_index,
                       f64 ping_interval, u32 ping_repeat, u32 data_len,
                       u32 verbose)
{
  int i;
  ping_main_t *pm = &ping_main;
  uword curr_proc = vlib_current_process (vm);
  u32 n_replies = 0;
  u32 n_requests = 0;
  ping_run_t *pr = 0;
  u32 ping_run_index = 0;
  u16 icmp_id;

  static u32 rand_seed = 0;

  if (PREDICT_FALSE(!rand_seed))
      rand_seed = random_default_seed();

  icmp_id = random_u32(&rand_seed) & 0xffff;

  while (hash_get (pm->ping_run_by_icmp_id, icmp_id))
    {
      vlib_cli_output (vm, "ICMP ID collision at %d, incrementing", icmp_id);
      icmp_id++;
    }
  pool_get (pm->ping_runs, pr);
  ping_run_index = pr - pm->ping_runs;
  pr->cli_process_id = curr_proc;
  pr->icmp_id = icmp_id;
  hash_set (pm->ping_run_by_icmp_id, icmp_id, ping_run_index);
  for (i = 1; i <= ping_repeat; i++)
    {
      f64 sleep_interval;
      f64 time_ping_sent = vlib_time_now (vm);
      /* Reset pr: running ping in other process could have changed pm->ping_runs */
      pr = vec_elt_at_index (pm->ping_runs, ping_run_index);
      pr->curr_seq = i;
      if (pa6 &&
          (SEND_PING_OK == send_ip6_ping (vm, ping_main.ip6_main, pa6,
                                          sw_if_index, i, icmp_id, data_len,
                                          verbose)))
        {
          n_requests++;
        }
      if (pa4 &&
          (SEND_PING_OK == send_ip4_ping (vm, ping_main.ip4_main, pa4,
                                          sw_if_index, i, icmp_id, data_len,
                                          verbose)))
        {
          n_requests++;
        }
      while ((i <= ping_repeat)
             &&
             ((sleep_interval =
               time_ping_sent + ping_interval - vlib_time_now (vm)) > 0.0))
        {
          uword event_type, *event_data = 0;
          vlib_process_wait_for_event_or_clock (vm, sleep_interval);
          event_type = vlib_process_get_events (vm, &event_data);
          switch (event_type)
            {
            case ~0:           /* no events => timeout */
              break;
            case PING_RESPONSE_IP6:
              {
                int i;
                for (i = 0; i < vec_len (event_data); i++)
                  {
                    u32 bi0 = event_data[0];
                    print_ip6_icmp_reply (vm, bi0);
                    n_replies++;
                    if (0 != bi0)
                      {
                        vlib_buffer_free (vm, &bi0, 1);
                      }
                  }
              }
              break;
            case PING_RESPONSE_IP4:
              {
                int i;
                for (i = 0; i < vec_len (event_data); i++)
                  {
                    u32 bi0 = event_data[0];
                    print_ip4_icmp_reply (vm, bi0);
                    n_replies++;
                    if (0 != bi0)
                      {
                        vlib_buffer_free (vm, &bi0, 1);
                      }
                  }
              }
              break;
            default:
              /* someone pressed a key, abort */
              vlib_cli_output (vm, "Aborted due to a keypress.");
              i = 1 + ping_repeat;
              break;
            }
        }
    }
  vlib_cli_output (vm, "\n");
  {
    float loss =
      (0 ==
       n_requests) ? 0 : 100.0 * ((float) n_requests -
                                  (float) n_replies) / (float) n_requests;
    vlib_cli_output (vm,
                     "Statistics: %u sent, %u received, %f%% packet loss\n",
                     n_requests, n_replies, loss);
    /* Reset pr: running ping in other process could have changed pm->ping_runs */
    pr = vec_elt_at_index (pm->ping_runs, ping_run_index);
    hash_unset (pm->ping_run_by_icmp_id, icmp_id);
    pool_put (pm->ping_runs, pr);
  }
}





static clib_error_t *
ping_ip_address (vlib_main_t * vm,
                 unformat_input_t * input, vlib_cli_command_t * cmd)
{
  ip4_address_t a4;
  ip6_address_t a6;
  clib_error_t *error = 0;
  u32 ping_repeat = 5;
  u8 ping_ip4, ping_ip6;
  vnet_main_t *vnm = vnet_get_main ();
  u32 data_len = PING_DEFAULT_DATA_LEN;
  u32 verbose = 0;
  f64 ping_interval = PING_DEFAULT_INTERVAL;
  ping_ip4 = ping_ip6 = 0;
  u32 sw_if_index;
  sw_if_index = ~0;
  if (unformat (input, "%U", unformat_ip4_address, &a4))
    {
      ping_ip4 = 1;
    }
  else if (unformat (input, "%U", unformat_ip6_address, &a6))
    {
      ping_ip6 = 1;
    }
  else if (unformat (input, "ipv4"))
    {
      if (unformat (input, "%U", unformat_ip4_address, &a4))
        {
          ping_ip4 = 1;
        }
      else
        {
          error =
            clib_error_return (0,
                               "expecting IPv4 address but got `%U'",
                               format_unformat_error, input);
        }
    }
  else if (unformat (input, "ipv6"))
    {
      if (unformat (input, "%U", unformat_ip6_address, &a6))
        {
          ping_ip6 = 1;
        }
      else
        {
          error =
            clib_error_return (0,
                               "expecting IPv6 address but got `%U'",
                               format_unformat_error, input);
        }
    }
  else
    {
      error =
        clib_error_return (0,
                           "expecting IP4/IP6 address `%U'. Usage: ping <addr> [source <intf>] [size <datasz>] [repeat <count>] [verbose]",
                           format_unformat_error, input);
      goto done;
    }

  /* allow for the second AF in the same ping */
  if (!ping_ip4 && (unformat (input, "ipv4")))
    {
      if (unformat (input, "%U", unformat_ip4_address, &a4))
        {
          ping_ip4 = 1;
        }
    }
  else if (!ping_ip6 && (unformat (input, "ipv6")))
    {
      if (unformat (input, "%U", unformat_ip6_address, &a6))
        {
          ping_ip6 = 1;
        }
    }

  /* parse the rest of the parameters  in a cycle */
  while (!unformat_eof (input, NULL))
    {
      if (unformat (input, "source"))
        {
          if (!unformat_user
              (input, unformat_vnet_sw_interface, vnm, &sw_if_index))
            {
              error =
                clib_error_return (0,
                                   "unknown interface `%U'",
                                   format_unformat_error, input);
              goto done;
            }
        }
      else if (unformat (input, "size"))
        {
          if (!unformat (input, "%u", &data_len))
            {
              error =
                clib_error_return (0,
                                   "expecting size but got `%U'",
                                   format_unformat_error, input);
              goto done;
            }
        }
      else if (unformat (input, "interval"))
        {
          if (!unformat (input, "%f", &ping_interval))
            {
              error =
                clib_error_return (0,
                                   "expecting interval (floating point number) got `%U'",
                                   format_unformat_error, input);
              goto done;
            }
        }
      else if (unformat (input, "repeat"))
        {
          if (!unformat (input, "%u", &ping_repeat))
            {
              error =
                clib_error_return (0,
                                   "expecting repeat count but got `%U'",
                                   format_unformat_error, input);
              goto done;
            }
        }
      else if (unformat (input, "verbose"))
        {
          verbose = 1;
        }
      else
        {
          error = clib_error_return (0, "unknown input `%U'",
                                     format_unformat_error, input);
          goto done;
        }
    }

  run_ping_ip46_address (vm, ping_ip4 ? &a4 : NULL, ping_ip6 ? &a6 : NULL,
                         sw_if_index, ping_interval, ping_repeat, data_len,
                         verbose);
done:
  return error;
}

/*?
 * This command sends an ICMP ECHO_REQUEST to network hosts. The address
 * can be an IPv4 or IPv6 address (or both at the same time).
 *
 * @cliexpar
 * @parblock
 * Example of how ping an IPv4 address:
 * @cliexstart{ping 172.16.1.2 source GigabitEthernet2/0/0 repeat 2}
 * 64 bytes from 172.16.1.2: icmp_seq=1 ttl=64 time=.1090 ms
 * 64 bytes from 172.16.1.2: icmp_seq=2 ttl=64 time=.0914 ms
 *
 * Statistics: 2 sent, 2 received, 0% packet loss
 * @cliexend
 *
 * Example of how ping both an IPv4 address and IPv6 address at the same time:
 * @cliexstart{ping 172.16.1.2 ipv6 fe80::24a5:f6ff:fe9c:3a36 source GigabitEthernet2/0/0 repeat 2 verbose}
 * Adjacency index: 10, sw_if_index: 1
 * Adj: ip6-discover-neighbor
 * Adj Interface: 0
 * Forced set interface: 1
 * Adjacency index: 0, sw_if_index: 4294967295
 * Adj: ip4-miss
 * Adj Interface: 0
 * Forced set interface: 1
 * Source address: 172.16.1.1
 * 64 bytes from 172.16.1.2: icmp_seq=1 ttl=64 time=.1899 ms
 * Adjacency index: 10, sw_if_index: 1
 * Adj: ip6-discover-neighbor
 * Adj Interface: 0
 * Forced set interface: 1
 * Adjacency index: 0, sw_if_index: 4294967295
 * Adj: ip4-miss
 * Adj Interface: 0
 * Forced set interface: 1
 * Source address: 172.16.1.1
 * 64 bytes from 172.16.1.2: icmp_seq=2 ttl=64 time=.0910 ms
 *
 * Statistics: 4 sent, 2 received, 50% packet loss
 * @cliexend
 * @endparblock
?*/
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (ping_command, static) =
{
  .path = "ping",
  .function = ping_ip_address,
  .short_help = "ping {<ip-addr> | ipv4 <ip4-addr> | ipv6 <ip6-addr>} [ipv4 <ip4-addr> | ipv6 <ip6-addr>] [source <interface>] [size <pktsize>] [interval <sec>] [repeat <cnt>] [verbose]",
};
/* *INDENT-ON* */

static clib_error_t *
ping_cli_init (vlib_main_t * vm)
{
  ping_main_t *pm = &ping_main;
  pm->ip6_main = &ip6_main;
  pm->ip4_main = &ip4_main;
  icmp6_register_type (vm, ICMP6_echo_reply, ip6_icmp_echo_reply_node.index);
  ip4_icmp_register_type (vm, ICMP4_echo_reply,
                          ip4_icmp_echo_reply_node.index);
  return 0;
}

VLIB_INIT_FUNCTION (ping_cli_init);