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/*
* stolen from net-tools-1.59 and stripped down for busybox by
* Erik Andersen <andersee@debian.org>
*
* Heavily modified by Manuel Novoa III Mar 12, 2001
*
* Version: $Id: inet_common.c,v 1.2 2002/06/06 12:11:55 andersen Exp $
*
*/
#include "inet_common.h"
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "libbb.h"
#ifdef DEBUG
#include <resolv.h>
#endif
const char bb_INET_default[]="default";
int INET_resolve(const char *name, struct sockaddr_in *s_in, int hostfirst)
{
struct hostent *hp;
struct netent *np;
/* Grmpf. -FvK */
s_in->sin_family = AF_INET;
s_in->sin_port = 0;
/* Default is special, meaning 0.0.0.0. */
if (!strcmp(name, bb_INET_default)) {
s_in->sin_addr.s_addr = INADDR_ANY;
return (1);
}
/* Look to see if it's a dotted quad. */
if (inet_aton(name, &s_in->sin_addr)) {
return 0;
}
/* If we expect this to be a hostname, try hostname database first */
#ifdef DEBUG
if (hostfirst) fprintf (stderr, "gethostbyname (%s)\n", name);
#endif
if (hostfirst &&
(hp = gethostbyname(name)) != (struct hostent *) NULL) {
memcpy((char *) &s_in->sin_addr, (char *) hp->h_addr_list[0],
sizeof(struct in_addr));
return 0;
}
/* Try the NETWORKS database to see if this is a known network. */
#ifdef DEBUG
fprintf (stderr, "getnetbyname (%s)\n", name);
#endif
if ((np = getnetbyname(name)) != (struct netent *) NULL) {
s_in->sin_addr.s_addr = htonl(np->n_net);
return 1;
}
if (hostfirst) {
/* Don't try again */
errno = h_errno;
return -1;
}
#ifdef DEBUG
res_init();
_res.options |= RES_DEBUG;
#endif
#ifdef DEBUG
fprintf (stderr, "gethostbyname (%s)\n", name);
#endif
if ((hp = gethostbyname(name)) == (struct hostent *) NULL) {
errno = h_errno;
return -1;
}
memcpy((char *) &s_in->sin_addr, (char *) hp->h_addr_list[0],
sizeof(struct in_addr));
return 0;
}
/* cache */
struct addr {
struct sockaddr_in addr;
char *name;
int host;
struct addr *next;
};
static struct addr *INET_nn = NULL; /* addr-to-name cache */
/* numeric: & 0x8000: default instead of *,
* & 0x4000: host instead of net,
* & 0x0fff: don't resolve
*/
int INET_rresolve(char *name, size_t len, struct sockaddr_in *s_in,
int numeric, unsigned int netmask)
{
struct hostent *ent;
struct netent *np;
struct addr *pn;
unsigned long ad, host_ad;
int host = 0;
/* Grmpf. -FvK */
if (s_in->sin_family != AF_INET) {
#ifdef DEBUG
fprintf(stderr, "rresolve: unsupport address family %d !\n", s_in->sin_family);
#endif
errno = EAFNOSUPPORT;
return (-1);
}
ad = (unsigned long) s_in->sin_addr.s_addr;
#ifdef DEBUG
fprintf (stderr, "rresolve: %08lx, mask %08x, num %08x \n", ad, netmask, numeric);
#endif
if (ad == INADDR_ANY) {
if ((numeric & 0x0FFF) == 0) {
if (numeric & 0x8000)
safe_strncpy(name, bb_INET_default, len);
else
safe_strncpy(name, "*", len);
return (0);
}
}
if (numeric & 0x0FFF) {
safe_strncpy(name, inet_ntoa(s_in->sin_addr), len);
return (0);
}
if ((ad & (~netmask)) != 0 || (numeric & 0x4000))
host = 1;
#if 0
INET_nn = NULL;
#endif
pn = INET_nn;
while (pn != NULL) {
if (pn->addr.sin_addr.s_addr == ad && pn->host == host) {
safe_strncpy(name, pn->name, len);
#ifdef DEBUG
fprintf (stderr, "rresolve: found %s %08lx in cache\n", (host? "host": "net"), ad);
#endif
return (0);
}
pn = pn->next;
}
host_ad = ntohl(ad);
np = NULL;
ent = NULL;
if (host) {
#ifdef DEBUG
fprintf (stderr, "gethostbyaddr (%08lx)\n", ad);
#endif
ent = gethostbyaddr((char *) &ad, 4, AF_INET);
if (ent != NULL)
safe_strncpy(name, ent->h_name, len);
} else {
#ifdef DEBUG
fprintf (stderr, "getnetbyaddr (%08lx)\n", host_ad);
#endif
np = getnetbyaddr(host_ad, AF_INET);
if (np != NULL)
safe_strncpy(name, np->n_name, len);
}
if ((ent == NULL) && (np == NULL))
safe_strncpy(name, inet_ntoa(s_in->sin_addr), len);
pn = (struct addr *) xmalloc(sizeof(struct addr));
pn->addr = *s_in;
pn->next = INET_nn;
pn->host = host;
pn->name = xstrdup(name);
INET_nn = pn;
return (0);
}
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