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/*
* test/resolve/resolve.c
*
* Copyright 1995 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* A simple program to test the functionality of the resolver library.
* It simply will try to get the IP address of the host, and then look
* up the name from the address. If the resulting name does not contain the
* domain name, then the resolve library is broken.
*
* Warning: It is possible to fool this program into thinking everything is
* alright byt a clever use of /etc/hosts - but this is better than nothing.
*
* Usage:
* resolve [hostname]
*
* When invoked with no arguments, gethostname is used for the local host.
*
*/
/* This program tests the resolve library and sees if it is broken... */
#include <stdio.h>
#if STDC_HEADERS
#include <string.h>
#else
#ifndef HAVE_STRCHR
#define strchr index
#endif
char *strchr();
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#include <netdb.h>
main(argc, argv)
int argc;
char **argv;
{
char myname[MAXHOSTNAMELEN+1];
char *ptr;
struct hostent *host;
int err;
if(argc > 1) {
strncpy(myname, argv[1], MAXHOSTNAMELEN);
} else {
if(gethostname(myname, MAXHOSTNAMELEN)) {
perror("gethostname failure");
exit(1);
}
}
myname[MAXHOSTNAMELEN] = '\0'; /* for safety */
/* Look up the address... */
printf("Hostname: %s\n", myname);
/* Set the hosts db to close each time - effectively rewinding file */
sethostent(0);
if((host = gethostbyname (myname)) == NULL) {
fprintf(stderr, "Could not look up hostname - fatal\n");
exit(2);
}
ptr = host->h_addr_list[0];
#define UC(a) (((int)a)&0xff)
printf("Host address: %d.%d.%d.%d\n",
UC(ptr[0]), UC(ptr[1]), UC(ptr[2]), UC(ptr[3]));
/* Convert back to full name */
if((host = gethostbyaddr(ptr, 4, AF_INET)) == NULL) {
fprintf(stderr, "Error looking up IP address - fatal\n");
exit(2);
}
printf("FQDN: %s\n", host->h_name);
if(strchr(host->h_name, '.') == NULL) {
fprintf(stderr, "\nResolve library did not return a fully qualified domain name\n");
fprintf(stderr, "You may have to reconfigure the kerberos distribution to select a\ndifferent set of libraries using --with-netlib[=libs]\n");
exit(3);
}
printf("Resolve library appears to have passed the test\n");
/* All ok */
exit(0);
}
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