* icmpquery.c - send and receive ICMP queries for address mask * and current time.

/*
 * icmpquery.c - send and receive ICMP queries for address mask
 *               and current time.
 *
 * Version 1.0.3
 *
 * Copyright 1998, 1999, 2000  David G. Andersen <angio@pobox.com>
 *                                        <danderse@cs.utah.edu>
 *                                        http://www.angio.net/
 *
 * All rights reserved.
 * This information is subject to change without notice and does not
 * represent a commitment on the part of David G. Andersen.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of David G. Andersen may not
 *    be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL DAVID G. ANDERSEN BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *
 *
 * Verified to work on:
 *    FreeBSD (2.x, 3.x)
 *    Linux 2.0.x, 2.2.0-pre1
 *    NetBSD 1.3
 *
 * Should work on Solaris and other platforms with BSD-ish stacks.
 *
 * If you compile it somewhere else, or it doesn't work somewhere,
 * please let me know.
 *
 * Compilation:  gcc icmpquery.c -o icmpquery
 *
 * One usage note:  In order to receive accurate time information,
 *                  the time on your computer must be correct; the
 *                  ICMP timestamp reply is a relative time figure.
 */


/* Some portions of this code are taken from FreeBSD's ping source.
 * Those portions are subject to the BSD copyright, which is appended
 * at the end of this file.  Namely, in_cksum.
 */

#include <time.h>
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <errno.h>
#include <string.h>
#include <signal.h>
#include <arpa/inet.h>

u_short in_cksum(u_short *addr, int len);

/*
 * We perform lookups on the hosts, and then store them in a chain
 * here.
 */

struct hostdesc {
char *hostname;
struct in_addr hostaddr;
struct hostdesc *next;
};

struct hostdesc *hostnames;
struct hostdesc *hosttail;

void resolv_from(char *hostfrom, struct in_addr *fromaddr)
{
struct hostent *hp;
if (hostfrom == NULL) {
fromaddr->s_addr = 0;
return;
}

if ((hp = gethostbyname(hostfrom)) == NULL) {
if ((fromaddr->s_addr = inet_addr(hostfrom)) == -1) {
fprintf(stderr, "could not resolve from address\n");
exit(0);
}
} else {
bcopy(hp->h_addr_list[0], &fromaddr->s_addr, hp->h_length);
}
}

/*
 * Set up the list of hosts.  Return the count.
 */

int makehosts(char **hostlist)
{
int i;
struct hostent *hp;
struct in_addr tmpaddr;
int hostcount = 0;

for (i = 0; hostlist[i]; i++) {
#ifdef DEBUG
printf("Resolving %s\n", hostlist[i]);
#endif
if ((hp = gethostbyname(hostlist[i])) == NULL) {
if ((tmpaddr.s_addr = inet_addr(hostlist[i]))) {
/* Could not resolve it.  Skip it. */
fprintf(stderr, "%s: unknown host\n",
hostlist[i]);
continue;
}
} else {
bcopy(hp->h_addr_list[0],
     &tmpaddr.s_addr, hp->h_length);
}

/* The host has been resolved.  Put it in the chain */
/* We want to stick it on the end. */
if (hostnames == NULL) {
hostnames = (struct hostdesc *)
malloc(sizeof(*hostnames));
if (hostnames == NULL) {
perror("hostnames malloc failed");
exit(-1);
}
hosttail = hostnames;
} else {
hosttail->next = (struct hostdesc *)
malloc(sizeof(*hostnames));
if (hosttail->next == NULL) {
perror("hosttail->next malloc failed");
exit(-1);
}
hosttail = hosttail->next;
}
hosttail->hostname = strdup(hostlist[i]);
if (hosttail->hostname == NULL) {
perror("strdup failed");
exit(-1);
}
hosttail->hostaddr = tmpaddr;
hosttail->next = NULL;
hostcount++;
}
return hostcount;
}

void usage(char *prog)
{
   fprintf(stderr,
  "%s  <-query> [-B] [-f fromhost] [-d delay] [-T time] targets\n"
  "    where <query> is one of:\n"
  "        -t : icmp timestamp request (default)\n"
  "        -m : icmp address mask request\n"
  "    The delay is in microseconds to sleep between packets.\n"
  "    targets is a list of hostnames or addresses\n"
  "    -T specifies the number of seconds to wait for a host to\n"
  "       respond.  The default is 5.\n"
  "    -B specifies \'broadcast\' mode.  icmpquery will wait\n"
  "       for timeout seconds and print all responses.\n"
  "    If you're on a modem, you may wish to use a larger -d and -T\n"
  ,prog);
}

/*
 * Set up a packet.  Returns the length of the ICMP portion.
 */

int initpacket(char *buf, int querytype, struct in_addr fromaddr)
{
   struct ip *ip = (struct ip *)buf;
   struct icmp *icmp = (struct icmp *)(ip + 1);

   /* things we customize */
   int icmplen = 0;

   ip->ip_src = fromaddr; /* if 0,  have kernel fill in */
   ip->ip_v = 4; /* Always use ipv4 for now */
   ip->ip_hl = sizeof *ip >> 2;
   ip->ip_tos = 0;
   ip->ip_id = htons(4321);
   ip->ip_ttl = 255;
   ip->ip_p = 1;
   ip->ip_sum = 0;                 /* kernel fills in */

   icmp->icmp_seq = 1;
   icmp->icmp_cksum = 0;
   icmp->icmp_type = querytype;
   icmp->icmp_code = 0;

   switch(querytype) {
   case ICMP_TSTAMP:
  gettimeofday( (struct timeval *)(icmp+8), NULL);
  bzero( icmp+12, 8);
  icmplen = 20;
  break;
   case ICMP_MASKREQ:
  *((char *)(icmp+8)) = 255;
  icmplen = 12;
  break;
   default:
  fprintf(stderr, "eek: unknown query type\n");
  exit(0);
   }
   ip->ip_len = sizeof(struct ip) + icmplen;
   return icmplen;
}
 
void sendpings(int s, int querytype, struct hostdesc *head, int delay,
      struct in_addr fromaddr)
   
{
char buf[1500];
struct ip *ip = (struct ip *)buf;
struct icmp *icmp = (struct icmp *)(ip + 1);
struct sockaddr_in dst;
int icmplen;

bzero(buf, 1500);
icmplen = initpacket(buf, querytype, fromaddr);
dst.sin_family = AF_INET;

while (head != NULL) {
#ifdef DEBUG
printf("pinging %s\n", head->hostname);
#endif
ip->ip_dst.s_addr = head->hostaddr.s_addr;
dst.sin_addr = head->hostaddr;
icmp->icmp_cksum = 0;
icmp->icmp_cksum = in_cksum((u_short *)icmp, icmplen);
if (sendto(s, buf, ip->ip_len, 0,
  (struct sockaddr *)&dst,
  sizeof(dst)) < 0) {
perror("sendto");
}
if (delay)
usleep(delay);
/* Don't flood the pipeline..kind of arbitrary */
head = head->next;
}
}

void myexit(int whatsig)
{
exit(0);
}

/*
 * Listen for 'hostcount' pings, print out the information, and
 * then exit.
 */

void recvpings(int s, int querytype, struct hostdesc *head, int hostcount,
      int broadcast)
{
char buf[1500];
struct ip *ip = (struct ip *)buf;
struct icmp *icmp;
int err = 0;
long int fromlen = 0;
int hlen;
struct timeval tv;
struct tm *tmtime;
int recvd = 0;
char *hostto;
char hostbuf[128], timebuf[128];
struct hostdesc *foundhost;
unsigned long int icmptime, icmpmask;

gettimeofday(&tv, NULL);

while (recvd < hostcount) {
if ((err = recvfrom(s, buf, sizeof buf, 0, NULL,
   (int *)&fromlen)) < 0)
{
perror("icmpquery:  recvfrom");
}
     
hlen = ip->ip_hl << 2;
icmp = (struct icmp *)(buf + hlen);

/* Find the host */
hostto = 0;
for (foundhost = head; foundhost != NULL;
    foundhost = foundhost->next) {
if (foundhost->hostaddr.s_addr == ip->ip_src.s_addr) {
hostto = foundhost->hostname;
break;
}
}

if (!hostto) {
sprintf(hostbuf, "unknown (%s)",
inet_ntoa(ip->ip_src));
hostto = hostbuf;
}

/* For time */
switch(icmp->icmp_type) {
case ICMP_TSTAMPREPLY:
icmptime = ntohl(icmp->icmp_ttime);
/* ms since midnight. yuch. */
tv.tv_sec -= tv.tv_sec%(24*60*60);
tv.tv_sec += (icmptime/1000);
tv.tv_usec = (icmptime%1000);
tmtime = localtime(&tv.tv_sec);
strftime(timebuf, 128, "%H:%M:%S", tmtime);
printf("%-40.40s:  %s\n", hostto, timebuf);
break;

case ICMP_MASKREPLY:
icmpmask = ntohl(icmp->icmp_dun.id_mask);
printf("%-40.40s:  0x%lX\n", hostto, icmpmask);
break;

default:
printf("Unknown ICMP message received (type %d)\n",
      icmp->icmp_type);
break;
}
if (!broadcast)
recvd++;
}
}

int
main(int argc, char **argv)
{
   int s;

   char *progname;
   extern char *optarg;         /* getopt variable declarations */
   char *hostfrom = NULL;
   extern int optind;
   extern int optopt;
   extern int opterr;
   char ch;                     /* Holds the getopt result */
   int on = 1;
   int hostcount;
   int delay = 0;
   int querytype = ICMP_TSTAMP;
   struct in_addr fromaddr;
   int timeout = 5;  /* Default to 5 seconds */
   int broadcast = 0; /* Should we wait for all responses? */

   fromaddr.s_addr = 0;

   progname = argv[0];

   while ((ch = getopt(argc, argv, "Btmf:d:T:")) != EOF)
      switch(ch)
      {
      case 'B':
     broadcast = 1;
     break;
      case 'd':
     delay = (int) strtol(optarg, NULL, 10);
     break;
      case 't': /* timestamp request */
     querytype = ICMP_TSTAMP;
     break;
      case 'm': /* address mask request */
     querytype = ICMP_MASKREQ;
     break;
      case 'f':
     hostfrom = optarg;
     resolv_from(hostfrom, &fromaddr);
     break;
      case 'T':
     timeout = (int) strtol(optarg, NULL, 10);
     break;
      default:
     usage(progname);
     exit(-1);
      }
   argc -= optind;
   argv += optind;

   if (!argv[0] || !strlen(argv[0]))
   {
      usage(progname);
      exit(-1);
   }

   hostcount = makehosts(argv);

   if ((s = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)) < 0) {
      perror("socket");
      exit(1);
   }
   if (setsockopt(s, IPPROTO_IP, IP_HDRINCL, &on, sizeof(on)) < 0) {
      perror("IP_HDRINCL");
      exit(1);
   }

   signal(SIGALRM, myexit);
   alarm(timeout);
   sendpings(s, querytype, hostnames, delay, fromaddr);
   recvpings(s, querytype, hostnames, hostcount, broadcast);
   exit(0);
}
 
/*
 * in_cksum --
 * Checksum routine for Internet Protocol family headers (C Version)
 *      From FreeBSD's ping.c
 */

u_short
in_cksum(addr, len)
u_short *addr;
int len;
{
register int nleft = len;
register u_short *w = addr;
register int sum = 0;
u_short answer = 0;

/*
* Our algorithm is simple, using a 32 bit accumulator (sum), we add
* sequential 16 bit words to it, and at the end, fold back all the
* carry bits from the top 16 bits into the lower 16 bits.
*/
while (nleft > 1)  {
sum += *w++;
nleft -= 2;
}

/* mop up an odd byte, if necessary */
if (nleft == 1) {
*(u_char *)(&answer) = *(u_char *)w ;
sum += answer;
}

/* add back carry outs from top 16 bits to low 16 bits */
sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */
sum += (sum >> 16); /* add carry */
answer = ~sum; /* truncate to 16 bits */
return(answer);
}


/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Mike Muuss.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */