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/* timestamp - ICMP timestamp requester
*
* FX <fx@phenoelit.de>
* Phenoelit (http://www.phenoelit.de)
*
* $Id: timestamp.c,v 1.1 2001/08/11 17:23:41 fx Exp $
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <netinet/in.h>
#include <rpc/types.h>
#include <netdb.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <errno.h>
#include <signal.h>
#include <sys/types.h>
#include <fcntl.h>
#include <time.h>
#include "protocols.h"
#include "packets.h"
void usage(char *n);
struct {
int verbose;
struct in_addr dest;
int timeout;
char *tdest;
} cfg;
void usage(char *n) {
fprintf(stderr,
"Usage: %s -d <destination> -t <timeout>\n"
,n);
}
int main(int argc, char **argv) {
char option;
extern char *optarg;
int rfd;
struct sockaddr_in to,from;
u_char *tpacket;
iphdr_t *ip;
icmphdr_t *icmp;
icmp_timestamp_t *stamp;
int psize;
u_int16_t cs;
int rc,addrsize,respond=0;
unsigned long start_t;
struct timespec sleeper = { 0, 10};
#define BSIZE (sizeof(iphdr_t)+sizeof(icmphdr_t)+200)
#define IDENT 0x0FF0
memset(&cfg,0,sizeof(cfg));
cfg.timeout=3;
while ((option=getopt(argc,argv,"vd:t:"))!=EOF) {
switch (option) {
case 'v': /* verbose */
cfg.verbose++;
break;
case 'd': /* destination, first as text */
cfg.tdest=smalloc(strlen(optarg)+1);
strcpy(cfg.tdest,optarg);
break;
case 't': if ((cfg.timeout=atoi(optarg))==0) {
fprintf(stderr,"%s is an invalid timeout\n",
optarg);
return (1);
}
break;
default: usage(argv[0]);
return (1);
}
}
/* check destination */
if (!cfg.tdest) {
fprintf(stderr,"You should really supply a destination with -d\n");
return (1);
} else {
/* try as a normal IP address */
if (inet_aton(cfg.tdest,&(cfg.dest))==0) {
/* ups, wasn't an IP - maybe a hostname */
struct hostent *hd;
if ((hd=gethostbyname(cfg.tdest))==NULL) {
fprintf(stderr,"Could not resolve destination host\n");
return (1);
} else {
bcopy(hd->h_addr,(char *)&(cfg.dest),hd->h_length);
/* memcpy((u_int8_t*)&(cfg.dest),
(u_int8_t*)&(hd->h_addr_list[0]),IP_ADDR_LEN); */
}
}
}
if ((rfd=socket(AF_INET,SOCK_RAW,IPPROTO_ICMP))<0) {
perror("socket(IPPROTO_ICMP)");
return (-1);
}
/* make the request packet */
psize=sizeof(icmphdr_t)+sizeof(icmp_timestamp_t);
tpacket=(u_char *)smalloc(psize+3);
/* make ICMP mask request */
icmp=(icmphdr_t *)tpacket;
icmp->type=ICMP_TIMESTAMP;
stamp=(icmp_timestamp_t *)(tpacket+sizeof(icmphdr_t));
stamp->identifier=htons(IDENT);
/* make up checksum */
cs=chksum((u_char *)icmp,psize);
icmp->checksum=cs;
memset(&to,0,sizeof(struct sockaddr_in));
to.sin_family=AF_INET;
to.sin_port=htons(0);
memcpy(&(to.sin_addr),&(cfg.dest),sizeof(to.sin_addr));
if (sendto(rfd,tpacket,psize,0,
(struct sockaddr *) &to,
sizeof(struct sockaddr_in)) <0) {
perror("sendto()");
return(-1);
}
rc= O_NONBLOCK | fcntl(rfd, F_GETFL);
fcntl(rfd,F_SETFL,rc);
/* make sure we have no junk in the mem */
memset(&from,0,sizeof(struct sockaddr_in));
addrsize=sizeof(struct sockaddr_in);
start_t=(unsigned long)time(NULL);
free(tpacket);
tpacket=(u_char *)smalloc(BSIZE);
psize=BSIZE;
respond=0;
while (start_t+cfg.timeout>=time(NULL)) {
if ((rc=recvfrom(rfd,(u_char *)tpacket,psize,0,
(struct sockaddr *)&from,
&addrsize))>=0) {
struct hostent *hr;
char *name;
ip=(iphdr_t *)tpacket;
/* got an ICMP response */
icmp=(icmphdr_t *)(tpacket+sizeof(iphdr_t));
stamp=(icmp_timestamp_t *)(tpacket+sizeof(iphdr_t)+
sizeof(icmphdr_t));
/* reverse lookup */
if ( (hr=gethostbyaddr((char *)&(from.sin_addr),
IP_ADDR_LEN,AF_INET))!=NULL) {
name=(char *)smalloc(strlen(hr->h_name)+
strlen(inet_ntoa(from.sin_addr))+4);
strcpy(name,hr->h_name);
strcat(name," [");
strcat(name,inet_ntoa(from.sin_addr));
strcat(name,"]");
} else {
name=(char *)smalloc(
strlen(inet_ntoa(from.sin_addr))+4);
strcat(name,"[");
strcat(name,inet_ntoa(from.sin_addr));
strcat(name,"]");
}
if (icmp->type==ICMP_TIMESTAMPREPLY) {
printf("%s\trecv/trans: %u/%u\n",
name,
ntohl(stamp->recvts),
ntohl(stamp->transts));
cfg.timeout=0;
/* printf("%s\t%s\n",
name,
ctime((time_t *)&(stamp->recvts))); */
}
}
nanosleep(&sleeper,NULL);
}
free(tpacket);
close(rfd);
return 0;
}
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