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/* $OpenBSD: dnsquery.c,v 1.4 1999/12/04 00:22:34 deraadt Exp $ */
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <netdb.h>
#include <resolv.h>
#include <errno.h>
#include "../conf/portability.h"
extern int errno;
extern int h_errno;
extern char *h_errlist[];
main(argc, argv)
int argc;
char *argv[];
{
char name[MAXDNAME];
u_char answer[8*1024];
register int c, i = 0;
unsigned long ul;
int nameservers = 0, class, type, len;
struct in_addr q_nsaddr[MAXNS];
struct hostent *q_nsname;
extern int optind, opterr;
extern char *optarg;
HEADER *hp;
int stream = 0, debug = 0;
/* set defaults */
len = MAXDNAME;
gethostname(name, len);
class = C_IN;
type = T_ANY;
/* if no args, exit */
if (argc == 1) {
fprintf(stderr, "Usage: %s [-h] host [-n ns] [-t type] [-c class] [-r retry] [-p period] [-s] [-v] [-d] [-a]\n", argv[0]);
exit(-1);
}
/* handle args */
while ((c = getopt(argc, argv, "c:dh:n:p:r:st:u:v")) != EOF) {
switch (c) {
case 'r' : _res.retry = atoi(optarg);
break;
case 'p' : _res.retrans = atoi(optarg);
break;
case 'h' : if (strlen(optarg) > sizeof(name)-1) {
fprintf(stderr,
"Domain name too long (%s)\n", optarg);
exit(-1);
}
strlcpy(name, optarg, sizeof name);
break;
case 'c' : {
int success, proto_class;
proto_class = sym_ston(__p_class_syms,
optarg, &success);
if (success)
class = proto_class;
else {
fprintf(stderr, "Bad class (%s)\n", optarg);
exit(-1);
}
}
break;
case 't' : {
int success, proto_type;
proto_type = sym_ston(__p_type_syms,
optarg, &success);
if (success)
type = proto_type;
else {
fprintf(stderr, "Bad type (%s)\n", optarg);
exit(-1);
}
}
break;
case 'd' : debug++;
break;
case 's' :
case 'v' : stream++;
break;
case 'n' :
/*
* If we set some nameservers here without
* using gethostbyname() first, then they will
* get overwritten when we do the first query.
* So, we must init the resolver before any
* of this.
*/
if (!(_res.options & RES_INIT))
if (res_init() == -1) {
fprintf(stderr,
"res_init() failed\n");
exit(-1);
}
if (nameservers >= MAXNS) break;
(void) inet_aton(optarg,
&q_nsaddr[nameservers]);
if (!inet_aton(optarg, &ul)) {
q_nsname = gethostbyname(optarg);
if (q_nsname == 0) {
fprintf(stderr,
"Bad nameserver (%s)\n",
optarg);
exit(-1);
}
bcopy((char *) q_nsname->h_addr,
(char *) &q_nsaddr[nameservers],
INADDRSZ);
}
else
q_nsaddr[nameservers].s_addr = ul;
nameservers++;
break;
default : fprintf(stderr,
"\tUsage: %s [-n ns] [-h host] [-t type] [-c class] [-r retry] [-p period] [-s] [-v] [-d] [-a]\n", argv[0]);
exit(-1);
}
}
if (optind < argc) {
if (strlen(argv[optind]) > sizeof(name)-1) {
fprintf(stderr,
"Domain name too long (%s)\n", argv[optind]);
exit(-1);
}
strlcpy(name, argv[optind], sizeof name);
}
len = sizeof(answer);
/*
* set these here so they aren't set for a possible call to
* gethostbyname above
*/
if (debug || stream) {
if (!(_res.options & RES_INIT))
if (res_init() == -1) {
fprintf(stderr, "res_init() failed\n");
exit(-1);
}
if (debug)
_res.options |= RES_DEBUG;
if (stream)
_res.options |= RES_USEVC;
}
/* if the -n flag was used, add them to the resolver's list */
if (nameservers != 0) {
_res.nscount = nameservers;
for (i = nameservers - 1; i >= 0; i--) {
_res.nsaddr_list[i].sin_addr.s_addr = q_nsaddr[i].s_addr;
_res.nsaddr_list[i].sin_family = AF_INET;
_res.nsaddr_list[i].sin_port = htons(NAMESERVER_PORT);
}
}
/*
* if the -h arg is fully-qualified, use res_query() since
* using res_search() will lead to use of res_querydomain()
* which will strip the trailing dot
*/
if (name[strlen(name) - 1] == '.') {
if (res_query(name, class, type, answer, len) < 0) {
hp = (HEADER *) answer;
if ((hp->rcode == 0) && (hp->ancount > 0))
__p_query(answer);
else
fprintf(stderr, "Query failed (h_errno = %d) : %s\n",
h_errno, h_errlist[h_errno]);
exit(-1);
}
}
else if (res_search(name, class, type, answer, len) < 0) {
hp = (HEADER *) answer;
if ((hp->rcode == 0) && (hp->ancount > 0))
__p_query(answer);
else
fprintf(stderr, "Query failed (h_errno = %d) : %s\n",
h_errno, h_errlist[h_errno]);
exit(-1);
}
__p_query(answer);
exit(0);
}
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