/*

	Nosuid TCP/IP ping 1.5 beta by Michal Zalewski <lcamtuf@ids.pl>
	---------------------------------------------------------------
 
	The Nosuid TCP/IP ping and related utilities are free software; you
	can redistribute it and/or modify it under the terms of the GNU Library
	General Public License as published by the Free Software Foundation;
	either version 2 of the License, or (at your option) any later version.

	changes by patrick haller http://www.haller.ws:
		ping now only uses ports 80, 22, 23, cycling through them. 
		this fixes pings to sites that filter like cnn.com or netscape.com

	hacked by Doug Warner <silfreed@silfreed.net> http://silfreed.net/
		to be used w/ nagios/netsaint
*/

#include <stdio.h>
#include <unistd.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdarg.h>
#include <errno.h>
#include <signal.h>
#include <stdlib.h>
#ifndef SOLARIS
#include <string.h>
#endif
#ifdef SOLARIS
#include <strings.h>
#endif

#define STATE_OK 0
#define STATE_WARNING 1
#define STATE_CRITICAL 2
#define STATE_UNKNOWN -1

char progname[] = "check_tcping";
char version[] = "0.1.5";
struct hostent *hp;
struct sockaddr_in s;
int suck,nic,to,tamto,count=5,delay=1,timeout=5,n=1,got,min,max,trip,port,warning_opt=0,critical_opt=0;
struct timeval tv,tv2;
char ad[20],ch;
struct sigaction siga;
int port_count = 0;
int ports[] = { 80, 22, 161, 23 }; 
int found_port = 0;
float wrta = 0.0;
float wpl  = 0.0;
float crta = 0.0;
float cpl  = 0.0;



void xerr(char* when)
{
	perror(when);
	exit(errno);
}


void usage(void)
{
	printf("usage:\n");
	printf(" %s [ -i delay] [ -n #packets] [ -t timeout] [ -p port]\n", progname);
	printf("    -w <rta>,<%%loss> -c <rta>,<%%loss> host\n");
	exit(STATE_UNKNOWN);
}


void alrm(int x)
{
	int old_port = 0;
	
	old_port = port;
	to=1; 
	if(! found_port){
		port_count++;
		port = ports[port_count%4];
		fprintf(stderr, "port %d not responding within timeout %d, changing to port %d<BR>\n", old_port, timeout, port);
	}
}


void stats(int x)
{
/*
	printf("\n-- %s ping statistics --\n",ad);
	printf("%d packet(s) transmitted, %d packet(s) received, %d%% packets lost.\n",n-1,got,(n-1-got)*100/(n-1));
	printf("round-trip statistics min/avg/max: ");
	if (got) {
		 printf("%.2f/%.2f/%.2f ms",(float)min/1000,(float)trip/got/1000,(float)max/1000);
		 if (min/1000<=0.1) printf(" (%d/%d/%d usecs)",min,trip/got,max);
		 printf(".\n");
	} else {
		printf("(not available due to 100%% packets lost).\n");
	}
	exit(0);
*/
	float currta = (float)trip/got/1000;
	float curpl = (n-1-got)*100/(n-1);
	int curstate = STATE_UNKNOWN;

	// determine current state
	if (currta < wrta && curpl < wpl && currta < crta && curpl < cpl) {
		curstate = STATE_OK;
	} else if ((currta >= wrta || curpl >= wpl) && (currta < crta && curpl < cpl)) {
		curstate = STATE_WARNING;
	} else if (currta >= crta || curpl >= cpl) {
		curstate = STATE_CRITICAL;
	} // end if state ok, warning, or critical

	// output current state
	printf("TCPING ");
	if (curstate == STATE_OK) {
		printf("OK");
	} else if (curstate == STATE_WARNING) {
		printf("WARNING");
	} else if (curstate == STATE_CRITICAL) {
		printf("CRITICAL");
	} else {
		printf("UNKNOWN");
	} // end if print stuff
	printf(": Packet loss = %.2f%%, RTA = ", curpl);
	if (got) {
		 printf("%.2f ms", currta);
	} else {
		printf("(not available due to 100%% packets lost)");
	}
	printf("\n");

	// exit w/ current state
	exit(curstate);
}


int main (int argc, char **argv)
{
	port = ports[port_count];

	//printf("Nosuid TCP/IP ping 1.5 beta by <lcamtuf@ids.pl>\n");
	while ((ch = getopt(argc, argv, "i:t:n:p:w:c:")) != EOF) {
		switch(ch) {
			case 'n':
				count=atoi(optarg);
				if (count<0) { fprintf(stderr,"%s: invalid number of pings.\n", progname);exit(STATE_UNKNOWN); }
				break;
			case 'i':
				delay=atoi(optarg);
				if (delay<1 || delay>1000) { fprintf(stderr,"%s: invalid ping delay.\n", progname);exit(STATE_UNKNOWN); }
				break;
			case 't':
				timeout=atoi(optarg);
				if (timeout<1 || timeout>100) { fprintf(stderr,"%s: invalid ping timeout.\n", progname);exit(STATE_UNKNOWN); }
				break;
			case 'p':
				port = atoi(optarg);
				break;
			case 'w':
				if (sscanf(optarg, "%f,%f", &wrta, &wpl) != 2) {
					fprintf(stderr, "%s: invalid number of options for warning\n", progname); exit(STATE_UNKNOWN);
				}
				warning_opt = 1;
				break;
			case 'c':
				if (sscanf(optarg, "%f,%f", &crta, &cpl) != 2) {
					fprintf(stderr, "%s: invalid number of options for critical\n", progname); exit(STATE_UNKNOWN);
				}
				critical_opt = 1;
				break;
			default:
				usage();
		}
	} // end while still opts
		
	if (argc-optind!=1) usage();
	
	min=timeout*1000000;
	
	hp=gethostbyname(argv[optind]);
	
	if (!hp) {
		printf("%s: host not found.\n", argv[0]);
		exit(STATE_UNKNOWN);
	}

	// test whether the warning or critical options were set
	if (warning_opt == 0) {
		printf("Warning option required\n");
		exit(STATE_UNKNOWN);
	} // end if no warning option
	if (critical_opt == 0) {
		printf("Critical option required\n");
		exit(STATE_UNKNOWN);
	} // end if no warning option
	
	nic=*(long*)hp->h_addr;
	
	sprintf(ad,"%d.%d.%d.%d",nic & 0xff,nic>>8 & 0xff,nic>>16 & 0xff, nic>>24 & 0xff);
		
	signal(SIGINT,stats);
	

	/* not needed for nagios - dw
	if (count) 
		printf("Pinging %s (%s) - %d packets, delay %d sec(s), timeout %d sec(s).\n",hp->h_name,ad,count,delay,timeout);
	else
		printf("Pinging %s (%s) - delay %d sec(s), timeout %d sec(s).\n",hp->h_name,ad,delay,timeout);
	*/

	while (n++<=count || !count) {
		bcopy(hp->h_addr,(void*)&s.sin_addr,hp->h_length);
		s.sin_family=hp->h_addrtype;
		s.sin_port=htons(port);
		if ((suck=socket(AF_INET,SOCK_STREAM,0))<0) xerr("ping");
		siga.sa_handler=alrm;
		errno=to=tamto=siga.sa_flags=0;
		sigaction(SIGALRM,&siga,NULL);
		alarm(timeout);
		gettimeofday(&tv,NULL);
		if (!connect(suck,(struct sockaddr *)&s,sizeof(s)))	{
			if (to || errno==EINTR) {
				printf("No ping reply from %s within %d second(s), changing port to %d...\n", ad,timeout, port);
			} else if (errno && errno!=ECONNREFUSED) {
				xerr("ping");
			}
		}
		gettimeofday(&tv2,NULL);
		alarm(timeout);
		if (!to ) {
			found_port=1;
			nic=(tv2.tv_sec-tv.tv_sec)*1000000+tv2.tv_usec-tv.tv_usec;
			/* not needed by nagios - dw
			if (nic/1000>=0.1) 
				printf("Ping reply from %s: seq=%d, time=%.2f ms\n",ad,n-1,(float)nic/1000);
			else 
				printf("Ping reply from %s: seq=%d, time=%d usecs\n",ad,n-1,nic);
			*/
			got++;
			trip+=nic;
			if (nic>max) max=nic;
			if (nic<min) min=nic;
			
		} 
		/*
		else if (! found_port){
			port_count++;
			port = ports[port_count % 3];
		}
		*/
		shutdown(suck,2);
		close(suck);
		usleep(delay*1000000);
	} // end while
	n--;

	stats(0);
	return(0);

} // end main();