ping.c

This is a short linux ping program

		t1->tv_sec++;
		t1->tv_usec -= 1000000;
	}
}


static void
sec_to_timeval(const double sec, struct timeval *tp)
{
	tp->tv_sec = sec;
	tp->tv_usec = (sec - tp->tv_sec) * 1000000.0;
}


static double
timeval_to_sec(const struct timeval *tp)
{
	return tp->tv_sec + tp->tv_usec / 1000000.0;
}


/*
 * Print statistics.
 * Heavily buffered STDIO is used here, so that all the statistics
 * will be written with 1 sys-write call.  This is nice when more
 * than one copy of the program is running on a terminal;  it prevents
 * the statistics output from becomming intermingled.
 */
static void
summary(int header)
{
	jiggle_flush(1);

	if (header)
		(void)printf("\n----%s PING Statistics----\n", hostname);
	(void)printf("%d packets transmitted, ", ntransmitted);
	(void)printf("%d packets received, ", nreceived);
	if (nrepeats)
		(void)printf("+%d duplicates, ", nrepeats);
	if (ntransmitted) {
		if (nreceived > ntransmitted)
			(void)printf("-- somebody's duplicating packets!");
		else
			(void)printf("%.1f%% packet loss",
				     (((ntransmitted-nreceived)*100.0) /
					    ntransmitted));
	}
	(void)printf("\n");
	if (nreceived && (pingflags & F_TIMING)) {
		double n = nreceived + nrepeats;
		double avg = (tsum / n);
		double variance = 0.0;
		if (n>1)
			variance = (tsumsq - n*avg*avg) /(n-1);

		printf("round-trip min/avg/max/stddev = "
			"%.3f/%.3f/%.3f/%.3f ms\n",
			tmin * 1000.0, avg * 1000.0,
			tmax * 1000.0, sqrt(variance) * 1000.0);
		if (pingflags & F_FLOOD) {
			double r = diffsec(&last_rx, &first_rx);
			double t = diffsec(&last_tx, &first_tx);
			if (r == 0)
				r = 0.0001;
			if (t == 0)
				t = 0.0001;
			(void)printf("  %.1f packets/sec sent, "
				     " %.1f packets/sec received\n",
				     ntransmitted/t, nreceived/r);
		}
	}
}


/*
 * Print statistics when SIGINFO is received.
 */
/* ARGSUSED */
static void
prtsig(int dummy)
{
	summary(0);
#ifdef SIGINFO
	(void)signal(SIGINFO, prtsig);
#else
	(void)signal(SIGQUIT, prtsig);
#endif
}


/*
 * On the first SIGINT, allow any outstanding packets to dribble in
 */
static void
prefinish(int dummy)
{
	if (lastrcvd			/* quit now if caught up */
	    || nreceived == 0)		/* or if remote is dead */
		finish(0);

	(void)signal(dummy, finish);	/* do this only the 1st time */

	if (npackets > ntransmitted)	/* let the normal limit work */
		npackets = ntransmitted;
}


/*
 * Print statistics and give up.
 */
/* ARGSUSED */
static void
finish(int dummy)
{
#if defined(SIGINFO) && defined(NOKERNINFO)
	struct termios ts;

	if (reset_kerninfo && tcgetattr (0, &ts) != -1) {
		ts.c_lflag &= ~NOKERNINFO;
		tcsetattr (STDIN_FILENO, TCSANOW, &ts);
	}
	(void)signal(SIGINFO, SIG_IGN);
#else
	(void)signal(SIGQUIT, SIG_DFL);
#endif

	summary(1);
	exit(nreceived > 0 ? 0 : 2);
}


static int				/* 0=do not print it */
ck_pr_icmph(struct icmp *icp,
	    struct sockaddr_in *from,
	    int cc,
	    int override)		/* 1=override VERBOSE if interesting */
{
	int	hlen;
	struct ip ipb, *ip = &ipb;
	struct icmp icp2b, *icp2 = &icp2b;
	int res;

	if (pingflags & F_VERBOSE) {
		res = 1;
		jiggle_flush(1);
	} else {
		res = 0;
	}

	(void) memcpy(ip, icp->icmp_data, sizeof(*ip));
	hlen = ip->ip_hl << 2;
	if (ip->ip_p == IPPROTO_ICMP
	    && hlen + 6 <= cc) {
		(void) memcpy(icp2, &icp->icmp_data[hlen], sizeof(*icp2));
		if (icp2->icmp_id == ident) {
			/* remember to clear route cached in kernel
			 * if this non-Echo-Reply ICMP message was for one
			 * of our packets.
			 */
			clear_cache.tv_sec = 0;

			if (!res && override
			    && (pingflags & (F_QUIET|F_SEMI_QUIET)) == 0) {
				jiggle_flush(1);
				(void)printf("%d bytes from %s: ",
					     cc, pr_addr(&from->sin_addr));
				res = 1;
			}
		}
	}

	return res;
}


/*
 *  Print a descriptive string about an ICMP header other than an echo reply.
 */
static int				/* 0=printed nothing */
pr_icmph(struct icmp *icp,
	 struct sockaddr_in *from,
	 int cc)
{
	switch (icp->icmp_type ) {
	case ICMP_UNREACH:
		if (!ck_pr_icmph(icp, from, cc, 1))
			return 0;
		switch (icp->icmp_code) {
		case ICMP_UNREACH_NET:
			(void)printf("Destination Net Unreachable");
			break;
		case ICMP_UNREACH_HOST:
			(void)printf("Destination Host Unreachable");
			break;
		case ICMP_UNREACH_PROTOCOL:
			(void)printf("Destination Protocol Unreachable");
			break;
		case ICMP_UNREACH_PORT:
			(void)printf("Destination Port Unreachable");
			break;
		case ICMP_UNREACH_NEEDFRAG:
			(void)printf("frag needed and DF set.  Next MTU=%d",
			       ntohs(icp->icmp_nextmtu));
			break;
		case ICMP_UNREACH_SRCFAIL:
			(void)printf("Source Route Failed");
			break;
		case ICMP_UNREACH_NET_UNKNOWN:
			(void)printf("Unreachable unknown net");
			break;
		case ICMP_UNREACH_HOST_UNKNOWN:
			(void)printf("Unreachable unknown host");
			break;
		case ICMP_UNREACH_ISOLATED:
			(void)printf("Unreachable host isolated");
			break;
		case ICMP_UNREACH_NET_PROHIB:
			(void)printf("Net prohibited access");
			break;
		case ICMP_UNREACH_HOST_PROHIB:
			(void)printf("Host prohibited access");
			break;
		case ICMP_UNREACH_TOSNET:
			(void)printf("Bad TOS for net");
			break;
		case ICMP_UNREACH_TOSHOST:
			(void)printf("Bad TOS for host");
			break;
		case 13:
			(void)printf("Communication prohibited");
			break;
		case 14:
			(void)printf("Host precedence violation");
			break;
		case 15:
			(void)printf("Precedence cutoff");
			break;
		default:
			(void)printf("Bad Destination Unreachable Code: %d",
				     icp->icmp_code);
			break;
		}
		/* Print returned IP header information */
		pr_retip(icp, cc);
		break;

	case ICMP_SOURCEQUENCH:
		if (!ck_pr_icmph(icp, from, cc, 1))
			return 0;
		(void)printf("Source Quench");
		pr_retip(icp, cc);
		break;

	case ICMP_REDIRECT:
		if (!ck_pr_icmph(icp, from, cc, 1))
			return 0;
		switch (icp->icmp_code) {
		case ICMP_REDIRECT_NET:
			(void)printf("Redirect Network");
			break;
		case ICMP_REDIRECT_HOST:
			(void)printf("Redirect Host");
			break;
		case ICMP_REDIRECT_TOSNET:
			(void)printf("Redirect Type of Service and Network");
			break;
		case ICMP_REDIRECT_TOSHOST:
			(void)printf("Redirect Type of Service and Host");
			break;
		default:
			(void)printf("Redirect--Bad Code: %d", icp->icmp_code);
			break;
		}
		(void)printf(" New router addr: %s",
			     pr_addr(&icp->icmp_hun.ih_gwaddr));
		pr_retip(icp, cc);
		break;

	case ICMP_ECHO:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Echo Request: ID=%d seq=%d",
			     ntohs(icp->icmp_id), ntohs(icp->icmp_seq));
		break;

	case ICMP_ECHOREPLY:
		/* displaying other's pings is too noisey */
#if 0
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Echo Reply: ID=%d seq=%d",
			     ntohs(icp->icmp_id), ntohs(icp->icmp_seq));
		break;
#else
		return 0;
#endif

	case ICMP_ROUTERADVERT:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Router Discovery Advert");
		break;

	case ICMP_ROUTERSOLICIT:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Router Discovery Solicit");
		break;

	case ICMP_TIMXCEED:
		if (!ck_pr_icmph(icp, from, cc, 1))
			return 0;
		switch (icp->icmp_code ) {
		case ICMP_TIMXCEED_INTRANS:
			(void)printf("Time To Live exceeded");
			break;
		case ICMP_TIMXCEED_REASS:
			(void)printf("Frag reassembly time exceeded");
			break;
		default:
			(void)printf("Time exceeded, Bad Code: %d",
				     icp->icmp_code);
			break;
		}
		pr_retip(icp, cc);
		break;

	case ICMP_PARAMPROB:
		if (!ck_pr_icmph(icp, from, cc, 1))
			return 0;
		(void)printf("Parameter problem: pointer = 0x%02x",
			     icp->icmp_hun.ih_pptr);
		pr_retip(icp, cc);
		break;

	case ICMP_TSTAMP:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Timestamp");
		break;

	case ICMP_TSTAMPREPLY:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Timestamp Reply");
		break;

	case ICMP_IREQ:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Information Request");
		break;

	case ICMP_IREQREPLY:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Information Reply");
		break;

	case ICMP_MASKREQ:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Address Mask Request");
		break;

	case ICMP_MASKREPLY:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Address Mask Reply");
		break;

	default:
		if (!ck_pr_icmph(icp, from, cc, 0))
			return 0;
		(void)printf("Bad ICMP type: %d", icp->icmp_type);
		if (pingflags & F_VERBOSE)
			pr_iph(icp, cc);
	}

	return 1;
}


/*
 *  Print an IP header with options.
 */
static void
pr_iph(struct icmp *icp,
       int cc)
{
	int	hlen;
	u_char	*cp;
	struct ip ipb, *ip = &ipb;

	(void) memcpy(ip, icp->icmp_data, sizeof(*ip));

	hlen = ip->ip_hl << 2;
	cp = (u_char *) &icp->icmp_data[20];	/* point to options */

	(void)printf("\n Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src	     Dst\n");
	(void)printf("  %1x  %1x  %02x %04x %04x",
		     ip->ip_v, ip->ip_hl, ip->ip_tos, ip->ip_len, ip->ip_id);
	(void)printf("   %1x %04x",
		     ((ip->ip_off)&0xe000)>>13, (ip->ip_off)&0x1fff);
	(void)printf("  %02x  %02x %04x",
		     ip->ip_ttl, ip->ip_p, ip->ip_sum);
	(void)printf(" %15s ",
		     inet_ntoa(*(struct in_addr *)&ip->ip_src.s_addr));
	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->ip_dst.s_addr));
	/* dump any option bytes */
	while (hlen-- > 20 && cp < (u_char*)icp+cc) {
		(void)printf("%02x", *cp++);
	}
}

/*
 * Print an ASCII host address starting from a string of bytes.
 */
static void
pr_saddr(u_char *cp)
{
	n_long l;
	struct in_addr addr;

	l = (u_char)*++cp;
	l = (l<<8) + (u_char)*++cp;
	l = (l<<8) + (u_char)*++cp;
	l = (l<<8) + (u_char)*++cp;
	addr.s_addr = htonl(l);
	(void)printf("\t%s", (l == 0) ? "0.0.0.0" : pr_addr(&addr));
}


/*
 *  Return an ASCII host address
 *  as a dotted quad and optionally with a hostname
 */
static char *
pr_addr(struct in_addr *addr)		/* in network order */
{
	struct	hostent	*hp;
	static	char buf[MAXHOSTNAMELEN+4+16+1];

	if ((pingflags & F_NUMERIC)
	    || !(hp = gethostbyaddr((char *)addr, sizeof(*addr), AF_INET))) {
		(void)snprintf(buf, sizeof(buf), "%s", inet_ntoa(*addr));
	} else {
		(void)snprintf(buf, sizeof(buf), "%s (%s)", hp->h_name,
		    inet_ntoa(*addr));
	}

	return buf;
}

/*
 *  Dump some info on a returned (via ICMP) IP packet.
 */
static void
pr_retip(struct icmp *icp,
	 int cc)
{
	int	hlen;
	u_char	*cp;
	struct ip ipb, *ip = &ipb;

	(void) memcpy(ip, icp->icmp_data, sizeof(*ip));

	if (pingflags & F_VERBOSE)
		pr_iph(icp, cc);

	hlen = ip->ip_hl << 2;
	cp = (u_char *) &icp->icmp_data[hlen];

	if (ip->ip_p == IPPROTO_TCP) {
		if (pingflags & F_VERBOSE)
			(void)printf("\n  TCP: from port %u, to port %u",
				     (*cp*256+*(cp+1)), (*(cp+2)*256+*(cp+3)));
	} else if (ip->ip_p == IPPROTO_UDP) {
		if (pingflags & F_VERBOSE)
			(void)printf("\n  UDP: from port %u, to port %u",
				     (*cp*256+*(cp+1)), (*(cp+2)*256+*(cp+3)));
	} else if (ip->ip_p == IPPROTO_ICMP) {
		struct icmp icp2;
		(void) memcpy(&icp2, cp, sizeof(icp2));
		if (icp2.icmp_type == ICMP_ECHO) {
			if (pingflags & F_VERBOSE)
				(void)printf("\n  ID=%u icmp_seq=%u",
					     ntohs((u_int16_t)icp2.icmp_id),
					     ntohs((u_int16_t)icp2.icmp_seq));
			else
				(void)printf(" for icmp_seq=%u",
					     ntohs((u_int16_t)icp2.icmp_seq));
		}
	}
}

static void
fill(void)
{
	int i, j, k;
	char *cp;
	int pat[16];

	for (cp = fill_pat; *cp != '\0'; cp++) {
		if (!isxdigit((unsigned char)*cp))
			break;
	}
	if (cp == fill_pat || *cp != '\0' || (cp-fill_pat) > 16*2) {
		(void)fflush(stdout);
		errx(1, "\"-p %s\": patterns must be specified with"
		     " 1-32 hex digits\n",
		     fill_pat);
	}

	i = sscanf(fill_pat,
		   "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x",
		    &pat[0], &pat[1], &pat[2], &pat[3],
		    &pat[4], &pat[5], &pat[6], &pat[7],
		    &pat[8], &pat[9], &pat[10], &pat[11],
		    &pat[12], &pat[13], &pat[14], &pat[15]);

	for (k=PHDR_LEN, j = 0; k <= datalen; k++) {
		opack_icmp.icmp_data[k] = pat[j];
		if (++j >= i)
			j = 0;
	}

	if (!(pingflags & F_QUIET)) {
		(void)printf("PATTERN: 0x");
		for (j=0; j<i; j++)
			(void)printf("%02x",
				     (u_char)opack_icmp.icmp_data[PHDR_LEN+j]);
		(void)printf("\n");
	}

}


static void
rnd_fill(void)
{
	static u_int32_t rnd;
	int i;

	for (i = PHDR_LEN; i < datalen; i++) {
		rnd = (3141592621U * rnd + 663896637U);
		opack_icmp.icmp_data[i] = rnd>>24;
	}
}


static void
gethost(const char *arg,
	const char *name,
	struct sockaddr_in *sa,
	char *realname,
	int realname_len)
{
	struct hostent *hp;

	(void)memset(sa, 0, sizeof(*sa));
	sa->sin_family = AF_INET;
	sa->sin_len = sizeof(struct sockaddr_in);

	/* If it is an IP address, try to convert it to a name to
	 * have something nice to display.
	 */
	if (inet_aton(name, &sa->sin_addr) != 0) {
		if (realname) {
			if (pingflags & F_NUMERIC)
				hp = 0;
			else
				hp = gethostbyaddr((char *)&sa->sin_addr,
						   sizeof(sa->sin_addr),
						   AF_INET);
			(void)strlcpy(realname, hp ? hp->h_name : name,
			    realname_len);
		}
		return;
	}
	
	hp = gethostbyname(name);
	if (!hp)
		errx(1, "Cannot resolve \"%s\" (%s)",name,hstrerror(h_errno));

	if (hp->h_addrtype != AF_INET)
		errx(1, "%s only supported with IP", arg);

	(void)memcpy(&sa->sin_addr, hp->h_addr, sizeof(sa->sin_addr));

	if (realname)
		(void)strlcpy(realname, hp->h_name, realname_len);
}


static void
usage(void)
{
#ifdef IPSEC
#ifdef IPSEC_POLICY_IPSEC
#define IPSECOPT	"\n     [-E policy] "
#else
#define IPSECOPT	"\n     [-AE] "
#endif /*IPSEC_POLICY_IPSEC*/
#else
#define IPSECOPT	""
#endif /*IPSEC*/

	(void)fprintf(stderr, "usage: \n"
	    "%s [-adDfLnoPqQrRv] [-c count] [-g gateway] [-h host]"
	    " [-i interval] [-I addr]\n"
	    "     [-l preload] [-p pattern] [-s size] [-t tos] [-T ttl]"
	    " [-w maxwait] " IPSECOPT "host\n",
	    getprogname());
	exit(1);
}