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/*
* Mini nslookup implementation for busybox
*
*
* Copyright (C) 2000 by Lineo, inc.
* Written by John Beppu <beppu@lineo.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include "internal.h"
#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <netdb.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
static const char nslookup_usage[] =
"only implementing non-interactive mode\n"
"I totally forgot nslookup even had an interactive mode\n"
;
/* */
static void
server_fprint(FILE *dst)
{
fprintf(dst, "Server: %s\n", "something");
fprintf(dst, "Address: %s\n\n", "something");
}
/* only works for IPv4 */
static int
addr_fprint(char *addr, FILE *dst)
{
uint8_t split[4];
uint32_t ip;
uint32_t *x = (uint32_t *) addr;
ip = ntohl(*x);
split[0] = (ip & 0xff000000) >> 24;
split[1] = (ip & 0x00ff0000) >> 16;
split[2] = (ip & 0x0000ff00) >> 8;
split[3] = (ip & 0x000000ff);
fprintf (
dst, "%d.%d.%d.%d",
split[0], split[1], split[2], split[3]
);
return 0;
}
/* */
static uint32_t
str_to_addr(const char *addr)
{
uint32_t split[4];
uint32_t ip;
sscanf(addr, "%d.%d.%d.%d",
&split[0], &split[1], &split[2], &split[3]);
/* assuming sscanf worked */
ip = (split[0] << 24) |
(split[1] << 16) |
(split[2] << 8) |
(split[3]);
return htonl(ip);
}
/* */
static int
addr_list_fprint(char **h_addr_list, FILE *dst)
{
int i;
char *addr_string = (h_addr_list[1])
? "Addresses"
: "Address";
fprintf(dst, "%s: ", addr_string);
for (i = 0; h_addr_list[i]; i++) {
addr_fprint(h_addr_list[i], dst);
if (h_addr_list[i+1]) {
fprintf(dst, ", ");
}
}
fprintf(dst,"\n");
return 0;
}
/* */
static struct hostent *
lookup_by_name(const char *hostname)
{
struct hostent *host;
host = gethostbyname(hostname);
if (host) {
fprintf(stdout, "Name: %s\n", host->h_name);
addr_list_fprint(host->h_addr_list, stdout);
} else {
herror("crap");
}
return host;
}
/* */
static struct hostent *
lookup_by_addr(const char *addr)
{
struct hostent *host;
host = gethostbyaddr(addr, 4, AF_INET); /* IPv4 only for now */
if (host) {
fprintf(stdout, "Name: %s\n", host->h_name);
addr_list_fprint(host->h_addr_list, stdout);
} else {
herror("crap");
}
return host;
}
/* */
static int
is_ip_address(const char *s)
{
while (*s) {
if ((isdigit(*s)) || (*s == '.')) { s++; continue; }
return 0;
}
return 1;
}
/* ________________________________________________________________________ */
int
nslookup_main(int argc, char **argv)
{
struct in_addr addr;
server_fprint(stdout);
if (is_ip_address(argv[1])) {
addr.s_addr = str_to_addr(argv[1]);
lookup_by_addr((char *) &addr);
} else {
lookup_by_name(argv[1]);
}
return 0;
}
/* $Id: nslookup.c,v 1.1 2000/01/29 12:59:01 beppu Exp $ */
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