inetutils/ping/ping6.c

/*
  Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013,
  2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Free Software
  Foundation, Inc.

  This file is part of GNU Inetutils.

  GNU Inetutils is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or (at
  your option) any later version.

  GNU Inetutils is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see `http://www.gnu.org/licenses/'. */

#include <config.h>

#ifdef __sun
#  define _XPG4_2	1	/* OpenSolaris: msg_control */
#endif /* __sun */

#include <sys/socket.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <signal.h>

#include <netinet/in.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <arpa/inet.h>

#include <netdb.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <argp.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#ifdef HAVE_LOCALE_H
# include <locale.h>
#endif
#if defined HAVE_IDN2_H && defined HAVE_IDN2
# include <idn2.h>
#elif defined HAVE_IDNA_H
# include <idna.h>
#endif

#include <unused-parameter.h>
#include <xalloc.h>
#include "ping6.h"
#include "libinetutils.h"

static PING *ping;
bool is_root = false;
unsigned char *data_buffer;
unsigned char *patptr;
int one = 1;
int pattern_len = MAXPATTERN;
size_t data_length = PING_DATALEN;
size_t count = DEFAULT_PING_COUNT;
size_t interval;
int socket_type;
int timeout = -1;
int hoplimit = 0;
unsigned int options;
static unsigned long preload = 0;
#ifdef IPV6_TCLASS
int tclass = -1;	/* Kernel sets default: -1, RFC 3542.  */
#endif
#ifdef IPV6_FLOWINFO
int flowinfo;
#endif

static int ping_echo (char *hostname);
static void ping_reset (PING * p);
static int send_echo (PING * ping);

const char args_doc[] = "HOST ...";
const char doc[] = "Send ICMP ECHO_REQUEST packets to network hosts."
                   "\vOptions marked with (root only) are available only to "
                   "superuser.";
const char *program_authors[] = {
	"Jeroen Dekkers",
	NULL
};

enum {
  ARG_HOPLIMIT = 256,
};

static struct argp_option argp_options[] = {
#define GRP 0
  {NULL, 0, NULL, 0, "Options valid for all request types:", GRP},
  {"count", 'c', "NUMBER", 0, "stop after sending NUMBER packets", GRP+1},
  {"debug", 'd', NULL, 0, "set the SO_DEBUG option", GRP+1},
#ifdef IPV6_FLOWINFO
  {"flowinfo", 'F', "N", 0, "set N as flow identifier", GRP+1},
#endif
  {"hoplimit", ARG_HOPLIMIT, "N", 0, "specify N as hop-limit", GRP+1},
  {"interval", 'i', "NUMBER", 0, "wait NUMBER seconds between sending each "
   "packet", GRP+1},
  {"numeric", 'n', NULL, 0, "do not resolve host addresses", GRP+1},
  {"ignore-routing", 'r', NULL, 0, "send directly to a host on an attached "
   "network", GRP+1},
#ifdef IPV6_TCLASS
  {"tos", 'T', "N", 0, "set traffic class to N", GRP+1},
#endif
  {"timeout", 'w', "N", 0, "stop after N seconds", GRP+1},
  {"ttl", ARG_HOPLIMIT, "N", 0, "synonym for --hoplimit", GRP+1},
  {"verbose", 'v', NULL, 0, "verbose output", GRP+1},
#undef GRP
#define GRP 10
  {NULL, 0, NULL, 0, "Options valid for --echo requests:", GRP},
  {"flood", 'f', NULL, 0, "flood ping (root only)", GRP+1},
  {"preload", 'l', "NUMBER", 0, "send NUMBER packets as fast as possible "
   "before falling into normal mode of behavior (root only)", GRP+1},
  {"pattern", 'p', "PATTERN", 0, "fill ICMP packet with given pattern (hex)",
   GRP+1},
  {"quiet", 'q', NULL, 0, "quiet output", GRP+1},
  {"size", 's', "NUMBER", 0, "send NUMBER data octets", GRP+1},
#undef GRP
  {NULL, 0, NULL, 0, NULL, 0}
};

static error_t
parse_opt (int key, char *arg, struct argp_state *state)
{
  char *endptr;
  static unsigned char pattern[MAXPATTERN];

  switch (key)
    {
    case 'c':
      count = ping_cvt_number (arg, 0, 0);
      break;

    case 'd':
      socket_type |= SO_DEBUG;
      break;

    case 'f':
      if (!is_root)
        error (EXIT_FAILURE, 0, "flooding needs root privilege");

      options |= OPT_FLOOD;
      setbuf (stdout, (char *) NULL);
      break;

#ifdef IPV6_FLOWINFO
    case 'F':
      options |= OPT_FLOWINFO;
      flowinfo = ping_cvt_number (arg, 0, 0) & IPV6_FLOWINFO_FLOWLABEL;
      break;
#endif

    case 'i':
      options |= OPT_INTERVAL;
      interval = ping_cvt_number (arg, 0, 0);
      interval *= PING_PRECISION;
      if (!is_root && interval < PING_MIN_USER_INTERVAL)
	error (EXIT_FAILURE, 0, "option value too small: %s", arg);
      break;

    case 'l':
      if (!is_root)
        error (EXIT_FAILURE, 0, "preloading needs root privilege");

      preload = strtoul (arg, &endptr, 0);
      if (*endptr || preload > INT_MAX)
        error (EXIT_FAILURE, 0, "preload size too large");

      break;

    case 'n':
      options |= OPT_NUMERIC;
      break;

    case 'p':
      decode_pattern (arg, &pattern_len, pattern);
      patptr = pattern;
      break;

    case 'q':
      options |= OPT_QUIET;
      break;

    case 'r':
      socket_type |= SO_DONTROUTE;
      break;

    case 's':
      data_length = ping_cvt_number (arg, PING_MAX_DATALEN, 1);
      break;

#ifdef IPV6_TCLASS
    case 'T':
      options |= OPT_TCLASS;
      tclass = ping_cvt_number (arg, 0, 0);
      break;
#endif

    case 'v':
      options |= OPT_VERBOSE;
      break;

    case 'w':
      timeout = ping_cvt_number (arg, INT_MAX, 0);
      break;

    case ARG_HOPLIMIT:
      hoplimit = ping_cvt_number (arg, 255, 0);
      break;

    case ARGP_KEY_NO_ARGS:
      argp_error (state, "missing host operand");

      /* FALLTHROUGH */
    default:
      return ARGP_ERR_UNKNOWN;
    }

  return 0;
}

static struct argp argp =
  {argp_options, parse_opt, args_doc, doc, NULL, NULL, NULL};

int
main (int argc, char **argv)
{
  int index;
  int status = 0;

  set_program_name (argv[0]);

# ifdef HAVE_SETLOCALE
  setlocale (LC_ALL, "");
# endif

  if (getuid () == 0)
    is_root = true;

  /* Parse command line */
  iu_argp_init ("ping6", program_authors);
  argp_parse (&argp, argc, argv, 0, &index, NULL);

  ping = ping_init (0, getpid ());
  if (ping == NULL)
    /* ping_init() prints our error message.  */
    exit (EXIT_FAILURE);

  setsockopt (ping->ping_fd, SOL_SOCKET, SO_BROADCAST, (char *) &one, sizeof (one));

  /* Reset root privileges */
  if (setuid (getuid ()) != 0)
    error (EXIT_FAILURE, errno, "setuid");

  /* Force line buffering regardless of output device.  */
  setvbuf (stdout, NULL, _IOLBF, 0);

  argc -= index;
  argv += index;

  if (count != 0)
    ping_set_count (ping, count);

  if (socket_type != 0)
    ping_set_sockopt (ping, socket_type, &one, sizeof (one));

  if (options & OPT_INTERVAL)
    ping_set_interval (ping, interval);

  if (hoplimit > 0)
    if (setsockopt (ping->ping_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
		    &hoplimit, sizeof (hoplimit)) < 0)
      error (0, errno, "setsockopt(IPV6_HOPLIMIT)");

#ifdef IPV6_TCLASS
  if (options & OPT_TCLASS)
    if (setsockopt (ping->ping_fd, IPPROTO_IPV6, IPV6_TCLASS,
		    &tclass, sizeof (tclass)) < 0)
      error (EXIT_FAILURE, errno, "setsockopt(IPV6_TCLASS)");
#endif

#ifdef IPV6_FLOWINFO
  if (options & OPT_FLOWINFO)
    if (setsockopt (ping->ping_fd, IPPROTO_IPV6, IPV6_FLOWINFO,
		    &flowinfo, sizeof (flowinfo)) < 0)
      error (EXIT_FAILURE, errno, "setsockopt(IPV6_FLOWINFO)");
#endif

  init_data_buffer (patptr, pattern_len);

  while (argc--)
    {
      status |= ping_echo (*argv++);
      ping_reset (ping);
    }

  return status;
}

static volatile int stop = 0;

static void
sig_int (int signal _GL_UNUSED_PARAMETER)
{
  stop = 1;
}

static int
ping_run (PING * ping, int (*finish) ())
{
  fd_set fdset;
  int fdmax;
  struct timeval resp_time;
  struct timeval last, intvl, now;
  struct timeval *t = NULL;
  int finishing = 0;
  size_t nresp = 0;
  unsigned long i;

  signal (SIGINT, sig_int);

  fdmax = ping->ping_fd + 1;

  /* Some systems use `struct timeval' of size 16.  As these are
   * not initialising `timeval' properly by assignment alone, let
   * us play safely here.  gettimeofday() is always sufficient.
   */
  memset (&resp_time, 0, sizeof (resp_time));
  memset (&intvl, 0, sizeof (intvl));
  memset (&now, 0, sizeof (now));

  for (i = 0; i < preload; i++)
    send_echo (ping);

  if (options & OPT_FLOOD)
    {
      intvl.tv_sec = 0;
      intvl.tv_usec = 10000;
    }
  else
    PING_SET_INTERVAL (intvl, ping->ping_interval);

  gettimeofday (&last, NULL);
  send_echo (ping);

  while (!stop)
    {
      int n;

      FD_ZERO (&fdset);
      FD_SET (ping->ping_fd, &fdset);

      gettimeofday (&now, NULL);
      resp_time.tv_sec = last.tv_sec + intvl.tv_sec - now.tv_sec;
      resp_time.tv_usec = last.tv_usec + intvl.tv_usec - now.tv_usec;

      while (resp_time.tv_usec < 0)
	{
	  resp_time.tv_usec += 1000000;
	  resp_time.tv_sec--;
	}
      while (resp_time.tv_usec >= 1000000)
	{
	  resp_time.tv_usec -= 1000000;
	  resp_time.tv_sec++;
	}

      if (resp_time.tv_sec < 0)
	resp_time.tv_sec = resp_time.tv_usec = 0;

      n = select (fdmax, &fdset, NULL, NULL, &resp_time);
      if (n < 0)
	{
	  if (errno != EINTR)
	    error (EXIT_FAILURE, errno, "select failed");
	  continue;
	}
      else if (n == 1)
	{
	  if (ping_recv (ping) == 0)
	    nresp++;
	  if (t == 0)
	    {
	      gettimeofday (&now, NULL);
	      t = &now;
	    }

	  if (ping_timeout_p (&ping->ping_start_time, timeout))
	    break;

	  if (ping->ping_count && nresp >= ping->ping_count)
	    break;
	}
      else
	{
	  if (!ping->ping_count || ping->ping_num_xmit < ping->ping_count)
	    {
	      send_echo (ping);
	      if (!(options & OPT_QUIET) && options & OPT_FLOOD)
		{
		  putchar ('.');
		}

	      if (ping_timeout_p (&ping->ping_start_time, timeout))
		break;
	    }
	  else if (finishing)
	    break;
	  else
	    {
	      finishing = 1;

	      intvl.tv_sec = MAXWAIT;
	    }
	  gettimeofday (&last, NULL);
	}
    }

  ping_unset_data (ping);

  if (finish)
    return (*finish) ();
  return 0;
}

static int
send_echo (PING * ping)
{
  size_t off = 0;
  int rc;

  if (PING_TIMING (data_length))
    {
      struct timeval tv;
      gettimeofday (&tv, NULL);
      ping_set_data (ping, &tv, 0, sizeof (tv), USE_IPV6);
      off += sizeof (tv);
    }
  if (data_buffer)
    ping_set_data (ping, data_buffer, off,
		   data_length > off ? data_length - off : data_length,
		   USE_IPV6);

  rc = ping_xmit (ping);
  if (rc < 0)
    error (EXIT_FAILURE, errno, "sending packet");

  return rc;
}

static int
ping_finish (void)
{
  fflush (stdout);
  printf ("--- %s ping statistics ---\n", ping->ping_hostname);
  printf ("%zu packets transmitted, ", ping->ping_num_xmit);
  printf ("%zu packets received, ", ping->ping_num_recv);
  if (ping->ping_num_rept)
    printf ("+%zu duplicates, ", ping->ping_num_rept);
  if (ping->ping_num_xmit)
    {
      if (ping->ping_num_recv > ping->ping_num_xmit)
	printf ("-- somebody's printing up packets!");
      else
	printf ("%d%% packet loss",
		(int) (((ping->ping_num_xmit - ping->ping_num_recv) * 100) /
		       ping->ping_num_xmit));

    }
  printf ("\n");
  return 0;
}

static int print_echo (int dup, int hops, struct ping_stat *stat,
		       struct sockaddr_in6 *dest, struct sockaddr_in6 *from,
		       struct icmp6_hdr *icmp6, int datalen);
static void print_icmp_error (struct sockaddr_in6 *from,
			      struct icmp6_hdr *icmp6, int len);

static int echo_finish (void);

static int
ping_echo (char *hostname)
{
  int err;
  char buffer[256];
  struct ping_stat ping_stat;
  int status;

  if (options & OPT_FLOOD && options & OPT_INTERVAL)
    error (EXIT_FAILURE, 0, "-f and -i incompatible options");

  memset (&ping_stat, 0, sizeof (ping_stat));
  ping_stat.tmin = 999999999.0;

  ping->ping_datalen = data_length;
  ping->ping_closure = &ping_stat;

  if (ping_set_dest (ping, hostname))
    error (EXIT_FAILURE, 0, "unknown host %s", hostname);

  err = getnameinfo ((struct sockaddr *) &ping->ping_dest.ping_sockaddr6,
		     sizeof (ping->ping_dest.ping_sockaddr6), buffer,
		     sizeof (buffer), NULL, 0, NI_NUMERICHOST);
  if (err)
    {
      const char *errmsg;

      if (err == EAI_SYSTEM)
	errmsg = strerror (errno);
      else
	errmsg = gai_strerror (err);

      error (EXIT_FAILURE, 0, "getnameinfo: %s", errmsg);
    }

  printf ("PING %s (%s): %zu data bytes",
	  ping->ping_hostname, buffer, data_length);
  if (options & OPT_VERBOSE)
    printf (", id 0x%04x = %u", ping->ping_ident, ping->ping_ident);

  printf ("\n");

  status = ping_run (ping, echo_finish);
  free (ping->ping_hostname);
  return status;
}

static void
ping_reset (PING * p)
{
  p->ping_num_xmit = 0;
  p->ping_num_recv = 0;
  p->ping_num_rept = 0;
}

static int
print_echo (int dupflag, int hops, struct ping_stat *ping_stat,
	    struct sockaddr_in6 *dest _GL_UNUSED_PARAMETER,
	    struct sockaddr_in6 *from,
	    struct icmp6_hdr *icmp6, int datalen)
{
  int err;
  char buf[256];
  struct timeval tv;
  int timing = 0;
  double triptime = 0.0;

  gettimeofday (&tv, NULL);

  /* Do timing */
  if (PING_TIMING (datalen - sizeof (struct icmp6_hdr)))
    {
      struct timeval tv1, *tp;

      timing++;
      tp = (struct timeval *) (icmp6 + 1);

      /* Avoid unaligned data: */
      memcpy (&tv1, tp, sizeof (tv1));
      tvsub (&tv, &tv1);

      triptime = ((double) tv.tv_sec) * 1000.0 +
	((double) tv.tv_usec) / 1000.0;
      ping_stat->tsum += triptime;
      ping_stat->tsumsq += triptime * triptime;
      if (triptime < ping_stat->tmin)
	ping_stat->tmin = triptime;
      if (triptime > ping_stat->tmax)
	ping_stat->tmax = triptime;
    }

  if (options & OPT_QUIET)
    return 0;
  if (options & OPT_FLOOD)
    {
      putchar ('\b');
      return 0;
    }

  err = getnameinfo ((struct sockaddr *) from, sizeof (*from),
		     buf, sizeof (buf), NULL, 0,
		     (options & OPT_NUMERIC) ? NI_NUMERICHOST
#ifdef NI_IDN
		     : NI_IDN
#else
		     : 0
#endif
		     );
  if (err)
    {
      const char *errmsg;

      if (err == EAI_SYSTEM)
	errmsg = strerror (errno);
      else
	errmsg = gai_strerror (err);

      fprintf (stderr, "ping: getnameinfo: %s\n", errmsg);

      strcpy (buf, "unknown");
    }

  printf ("%d bytes from %s: icmp_seq=%u", datalen, buf,
	  ntohs (icmp6->icmp6_seq));
  if (hops >= 0)
    printf (" ttl=%d", hops);
  if (timing)
    printf (" time=%.3f ms", triptime);
  if (dupflag)
    printf (" (DUP!)");

  putchar ('\n');

  return 0;
}

#define NITEMS(a) sizeof(a)/sizeof((a)[0])

struct icmp_code_descr
{
  int code;
  char *diag;
};

static struct icmp_code_descr icmp_dest_unreach_desc[] = {
  {ICMP6_DST_UNREACH_NOROUTE, "No route to destination"},
  {ICMP6_DST_UNREACH_ADMIN, "Destination administratively prohibited"},
  {ICMP6_DST_UNREACH_BEYONDSCOPE, "Beyond scope of source address"},
  {ICMP6_DST_UNREACH_ADDR, "Address unreachable"},
  {ICMP6_DST_UNREACH_NOPORT, "Port unreachable"},
};

static void
print_dst_unreach (struct icmp6_hdr *icmp6)
{
  struct icmp_code_descr *p;

  printf ("Destination unreachable: ");
  for (p = icmp_dest_unreach_desc;
       p < icmp_dest_unreach_desc + NITEMS (icmp_dest_unreach_desc); p++)
    {
      if (p->code == icmp6->icmp6_code)
	{
	  puts (p->diag);
	  return;
	}
    }

  printf ("Unknown code %d\n", icmp6->icmp6_code);
}

static void
print_packet_too_big (struct icmp6_hdr *icmp6)
{
  printf ("Packet too big, mtu=%u\n", icmp6->icmp6_mtu);
}

static struct icmp_code_descr icmp_time_exceeded_desc[] = {
  {ICMP6_TIME_EXCEED_TRANSIT, "Hop limit exceeded"},
  {ICMP6_TIME_EXCEED_REASSEMBLY, "Fragment reassembly timeout"},
};

static void
print_time_exceeded (struct icmp6_hdr *icmp6)
{
  struct icmp_code_descr *p;

  printf ("Time exceeded: ");
  for (p = icmp_time_exceeded_desc;
       p < icmp_time_exceeded_desc + NITEMS (icmp_time_exceeded_desc); p++)
    {
      if (p->code == icmp6->icmp6_code)
	{
	  puts (p->diag);
	  return;
	}
    }

  printf ("Unknown code %d\n", icmp6->icmp6_code);
}

static struct icmp_code_descr icmp_param_prob_desc[] = {
  {ICMP6_PARAMPROB_HEADER, "Erroneous header field"},
  {ICMP6_PARAMPROB_NEXTHEADER, "Unrecognized Next Header type"},
  {ICMP6_PARAMPROB_OPTION, "Unrecognized IPv6 option"},
};

static void
print_param_prob (struct icmp6_hdr *icmp6)
{
  struct icmp_code_descr *p;

  printf ("Parameter problem: ");
  for (p = icmp_param_prob_desc;
       p < icmp_param_prob_desc + NITEMS (icmp_param_prob_desc); p++)
    {
      if (p->code == icmp6->icmp6_code)
	{
	  puts (p->diag);
	  return;
	}
    }

  printf ("Unknown code %d\n", icmp6->icmp6_code);
}

void
print_ip_data (struct icmp6_hdr *icmp6)
{
  size_t j;
  struct ip6_hdr *ip = (struct ip6_hdr *) ((char *) icmp6 + sizeof (*icmp6));
  char src[INET6_ADDRSTRLEN], dst[INET6_ADDRSTRLEN];

  (void) inet_ntop (AF_INET6, &ip->ip6_dst, dst, sizeof (dst));
  (void) inet_ntop (AF_INET6, &ip->ip6_src, src, sizeof (src));

  printf ("IP Header Dump:\n ");
  for (j = 0; j < sizeof (*ip) - sizeof (ip->ip6_src) - sizeof (ip->ip6_dst); ++j)
    printf ("%02x%s", *((unsigned char *) ip + j),
	    (j % 2) ? " " : "");	/* Group bytes two by two.  */
  printf ("(src) (dst)\n");

  printf ("Vr TC Flow Plen Nxt Hop Src\t\t  Dst\n");
  printf (" %1x %02x %04x %4hu %3hhu %3hhu %s %s\n",
	  ntohl (ip->ip6_flow) >> 28,
	  (ntohl (ip->ip6_flow) & 0x0fffffff) >> 20,
	  ntohl (ip->ip6_flow) & 0x0fffff,
	  ntohs (ip->ip6_plen), ip->ip6_nxt, ip->ip6_hlim,
	  src, dst);

  switch (ip->ip6_nxt)
    {
    case IPPROTO_ICMPV6:
      {
	struct icmp6_hdr *hdr =
	  (struct icmp6_hdr *) ((unsigned char *) ip + sizeof (*ip));

	printf ("ICMP: type %hhu, code %hhu, size %hu",
		hdr->icmp6_type, hdr->icmp6_code, ntohs (ip->ip6_plen));
	switch (hdr->icmp6_type)
	  {
	  case ICMP6_ECHO_REQUEST:
	  case ICMP6_ECHO_REPLY:
	    printf (", id 0x%04x, seq 0x%04x",
		    ntohs (hdr->icmp6_id), ntohs (hdr->icmp6_seq));
	    break;
	  default:
	    break;
	  }
      }
      break;
    default:
      break;
    }

  printf ("\n");
}

static struct icmp_diag
{
  int type;
  void (*func) (struct icmp6_hdr *);
} icmp_diag[] = {
  {ICMP6_DST_UNREACH, print_dst_unreach},
  {ICMP6_PACKET_TOO_BIG, print_packet_too_big},
  {ICMP6_TIME_EXCEEDED, print_time_exceeded},
  {ICMP6_PARAM_PROB, print_param_prob},
};

static void
print_icmp_error (struct sockaddr_in6 *from, struct icmp6_hdr *icmp6, int len)
{
  char *s;
  struct icmp_diag *p;

  s = ipaddr2str ((struct sockaddr *) from, sizeof (*from));
  printf ("%d bytes from %s: ", len, s);
  free (s);

  for (p = icmp_diag; p < icmp_diag + NITEMS (icmp_diag); p++)
    {
      if (p->type == icmp6->icmp6_type)
	{
	  p->func (icmp6);
	  if (options & OPT_VERBOSE)
	    print_ip_data (icmp6);

	  return;
	}
    }

  /* This should never happen because of the ICMP6_FILTER set in
     ping_init(). */
  printf ("Unknown ICMP type: %d\n", icmp6->icmp6_type);
}

static int
echo_finish (void)
{
  ping_finish ();
  if (ping->ping_num_recv && PING_TIMING (data_length))
    {
      struct ping_stat *ping_stat = (struct ping_stat *) ping->ping_closure;
      double total = ping->ping_num_recv + ping->ping_num_rept;
      double avg = ping_stat->tsum / total;
      double vari = ping_stat->tsumsq / total - avg * avg;

      printf ("round-trip min/avg/max/stddev = %.3f/%.3f/%.3f/%.3f ms\n",
	      ping_stat->tmin, avg, ping_stat->tmax, nsqrt (vari, 0.0005));
    }
  return (ping->ping_num_recv == 0);
}

static PING *
ping_init (int type _GL_UNUSED_PARAMETER, int ident)
{
  int fd, err;
  const int on = 1;
  PING *p;
  struct icmp6_filter filter;

  /* Initialize raw ICMPv6 socket */
  fd = socket (PF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
  if (fd < 0)
    {
      if (errno == EPERM || errno == EACCES)
        error (EXIT_FAILURE, errno, "raw socket");

      return NULL;
    }

  /* Tell which ICMPs we are interested in.  */
  ICMP6_FILTER_SETBLOCKALL (&filter);
  ICMP6_FILTER_SETPASS (ICMP6_ECHO_REPLY, &filter);
  ICMP6_FILTER_SETPASS (ICMP6_DST_UNREACH, &filter);
  ICMP6_FILTER_SETPASS (ICMP6_PACKET_TOO_BIG, &filter);
  ICMP6_FILTER_SETPASS (ICMP6_TIME_EXCEEDED, &filter);
  ICMP6_FILTER_SETPASS (ICMP6_PARAM_PROB, &filter);

  err =
    setsockopt (fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filter, sizeof (filter));
  if (err)
    {
      close (fd);
      return NULL;
    }

  err = setsockopt (fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, sizeof (on));
  if (err)
    {
      close (fd);
      return NULL;
    }

  /* Allocate PING structure and initialize it to default values */
  p = malloc (sizeof (*p));
  if (!p)
    {
      close (fd);
      return NULL;
    }

  memset (p, 0, sizeof (*p));

  p->ping_fd = fd;
  p->ping_count = DEFAULT_PING_COUNT;
  p->ping_interval = PING_DEFAULT_INTERVAL;
  p->ping_datalen = sizeof (struct timeval);
  /* Make sure we use only 16 bits in this field, id for icmp is a unsigned short.  */
  p->ping_ident = ident & 0xFFFF;
  p->ping_cktab_size = PING_CKTABSIZE;
  gettimeofday (&p->ping_start_time, NULL);
  return p;
}

static int
ping_xmit (PING * p)
{
  int i, buflen;
  struct icmp6_hdr *icmp6;

  if (_ping_setbuf (p, USE_IPV6))
    return -1;

  buflen = p->ping_datalen + sizeof (struct icmp6_hdr);

  /* Mark sequence number as sent */
  _PING_CLR (p, p->ping_num_xmit);

  icmp6 = (struct icmp6_hdr *) p->ping_buffer;
  icmp6->icmp6_type = ICMP6_ECHO_REQUEST;
  icmp6->icmp6_code = 0;
  /* The checksum will be calculated by the TCP/IP stack.  */
  icmp6->icmp6_cksum = 0;
  icmp6->icmp6_id = htons (p->ping_ident);
  icmp6->icmp6_seq = htons (p->ping_num_xmit);

  i = sendto (p->ping_fd, (char *) p->ping_buffer, buflen, 0,
	      (struct sockaddr *) &p->ping_dest.ping_sockaddr6,
	      sizeof (p->ping_dest.ping_sockaddr6));
  if (i < 0)
    return -1;
  else
    {
      p->ping_num_xmit++;
      if (i != buflen)
	printf ("ping: wrote %s %d chars, ret=%d\n",
		p->ping_hostname, buflen, i);
    }

  return 0;
}

static int
my_echo_reply (PING * p, struct icmp6_hdr *icmp6)
{
  struct ip6_hdr *orig_ip = (struct ip6_hdr *) (icmp6 + 1);
  struct icmp6_hdr *orig_icmp = (struct icmp6_hdr *) (orig_ip + 1);

  return IN6_ARE_ADDR_EQUAL (&orig_ip->ip6_dst, &ping->ping_dest.ping_sockaddr6.sin6_addr)
    && orig_ip->ip6_nxt == IPPROTO_ICMPV6
    && orig_icmp->icmp6_type == ICMP6_ECHO_REQUEST
    && orig_icmp->icmp6_id == htons (p->ping_ident);
}

static int
ping_recv (PING * p)
{
  int dupflag, n;
  int hops = -1;
  struct msghdr msg;
  struct iovec iov;
  struct icmp6_hdr *icmp6;
  struct cmsghdr *cmsg;
  char cmsg_data[1024];

  iov.iov_base = p->ping_buffer;
  iov.iov_len = _PING_BUFLEN (p, USE_IPV6);
  msg.msg_name = &p->ping_from.ping_sockaddr6;
  msg.msg_namelen = sizeof (p->ping_from.ping_sockaddr6);
  msg.msg_iov = &iov;
  msg.msg_iovlen = 1;
  msg.msg_control = cmsg_data;
  msg.msg_controllen = sizeof (cmsg_data);
  msg.msg_flags = 0;

  n = recvmsg (p->ping_fd, &msg, 0);
  if (n < 0)
    return -1;

  for (cmsg = CMSG_FIRSTHDR (&msg); cmsg; cmsg = CMSG_NXTHDR (&msg, cmsg))
    {
      if (cmsg->cmsg_level == IPPROTO_IPV6
	  && cmsg->cmsg_type == IPV6_HOPLIMIT)
	{
	  hops = *(int *) CMSG_DATA (cmsg);
	  break;
	}
    }

  icmp6 = (struct icmp6_hdr *) p->ping_buffer;
  if (icmp6->icmp6_type == ICMP6_ECHO_REPLY)
    {
      /* We got an echo reply.  */
      if (ntohs (icmp6->icmp6_id) != p->ping_ident)
	return -1;		/* It's not a response to us.  */

      if (_PING_TST (p, ntohs (icmp6->icmp6_seq)))
	{
	  /* We already got the reply for this echo request.  */
	  p->ping_num_rept++;
	  dupflag = 1;
	}
      else
	{
	  _PING_SET (p, ntohs (icmp6->icmp6_seq));
	  p->ping_num_recv++;
	  dupflag = 0;
	}

      print_echo (dupflag, hops, p->ping_closure, &p->ping_dest.ping_sockaddr6,
		  &p->ping_from.ping_sockaddr6, icmp6, n);

    }
  else
    {
      /* We got an error reply.  */
      if (!my_echo_reply (p, icmp6))
	return -1;		/* It's not for us.  */

      print_icmp_error (&p->ping_from.ping_sockaddr6, icmp6, n);
    }

  return 0;
}

static int
ping_set_dest (PING * ping, const char *host)
{
  int err;
  struct addrinfo *result, hints;
  char *rhost;

#if defined HAVE_IDN || defined HAVE_IDN2
  err = idna_to_ascii_lz (host, &rhost, 0);
  if (err)
    return 1;
  host = rhost;
#else /* !HAVE_IDN && !HAVE_IDN2 */
  rhost = NULL;
#endif

  memset (&hints, 0, sizeof (hints));
  hints.ai_family = AF_INET6;
  hints.ai_flags = AI_CANONNAME;
#ifdef AI_IDN
  hints.ai_flags |= AI_IDN;
#endif
#ifdef AI_CANONIDN
  hints.ai_flags |= AI_CANONIDN;
#endif

  err = getaddrinfo (host, NULL, &hints, &result);
  if (err)
    {
      free (rhost);
      return 1;
    }

  memcpy (&ping->ping_dest.ping_sockaddr6, result->ai_addr, result->ai_addrlen);

  if (result->ai_canonname)
    ping->ping_hostname = strdup (result->ai_canonname);
  else
#if defined HAVE_IDN || defined HAVE_IDN2
    ping->ping_hostname = host;
#else
  ping->ping_hostname = strdup (host);
#endif
  freeaddrinfo (result);

  if (!ping->ping_hostname)
    return 1;

  return 0;
}