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/*
*
* Connection Manager
*
* Copyright (C) 2007-2010 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <unistd.h>
#include <string.h>
#include <resolv.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
static int do_connect(const char *server)
{
struct sockaddr_in sin;
int sk;
sk = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
//sk = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (sk < 0)
return -1;
memset(&sin, 0, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_port = htons(53);
sin.sin_addr.s_addr = inet_addr(server);
if (connect(sk, (struct sockaddr *) &sin, sizeof(sin)) < 0) {
close(sk);
return -1;
}
return sk;
}
int main(int argc, char *argv[])
{
ns_msg msg;
ns_rr rr;
int rcode;
const char *nameserver;
unsigned char buf[4096];
int i, sk, err, len, off = 0;
if (argc < 2) {
printf("missing argument\n");
return 1;
}
if (argc > 2)
nameserver = argv[2];
else
nameserver = "127.0.0.1";
sk = do_connect(nameserver);
if (sk < 0) {
printf("Can't connect\n");
return 1;
}
len = res_mkquery(ns_o_query, argv[1], ns_c_in, ns_t_a,
NULL, 0, NULL, buf + off, sizeof(buf) - off);
printf("query len: %d\n", len);
if (off > 0) {
buf[0] = len >> 8;
buf[1] = len & 0xff;
}
//for (i = 0; i < len + off; i++)
// printf("%02x ", buf[i]);
//printf("\n");
err = send(sk, buf, len + off, 0);
printf("send result: %d\n", err);
len = recv(sk, buf, sizeof(buf), 0);
printf("answer len: %d\n", len);
//for (i = 0; i < len + off; i++)
// printf("%02x ", buf[i]);
//printf("\n");
close(sk);
ns_initparse(buf + off, len - off, &msg);
rcode = ns_msg_getflag(msg, ns_f_rcode);
printf("msg id: 0x%04x\n", ns_msg_id(msg));
printf("msg rcode: %d\n", rcode);
printf("msg count: %d\n", ns_msg_count(msg, ns_s_an));
for (i = 0; i < ns_msg_count(msg, ns_s_an); i++) {
char result[100];
ns_parserr(&msg, ns_s_an, i, &rr);
if (ns_rr_class(rr) != ns_c_in)
continue;
if (ns_rr_type(rr) != ns_t_a)
continue;
if (ns_rr_rdlen(rr) != NS_INADDRSZ)
continue;
inet_ntop(AF_INET, ns_rr_rdata(rr), result, sizeof(result));
printf("result: %s\n", result);
}
return 0;
}
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