/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996,1999 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#if !defined(LINT) && !defined(CODECENTER)
static const char rcsid[] = "$Id: getnetent.c,v 1.7 2005/04/27 04:56:25 sra Exp $";
#endif
/* Imports */
#include "port_before.h"
#if !defined(__BIND_NOSTATIC)
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#include <resolv.h>
#include <stdlib.h>
#include <string.h>
#include <irs.h>
#include "port_after.h"
#include "irs_p.h"
#include "irs_data.h"
/* Definitions */
struct pvt {
struct netent netent;
char * aliases[1];
char name[MAXDNAME + 1];
};
/* Forward */
static struct net_data *init(void);
static struct netent *nw_to_net(struct nwent *, struct net_data *);
static void freepvt(struct net_data *);
static struct netent *fakeaddr(const char *, int af, struct net_data *);
/* Portability */
#ifndef INADDR_NONE
# define INADDR_NONE 0xffffffff
#endif
/* Public */
struct netent *
getnetent() {
struct net_data *net_data = init();
return (getnetent_p(net_data));
}
struct netent *
getnetbyname(const char *name) {
struct net_data *net_data = init();
return (getnetbyname_p(name, net_data));
}
struct netent *
getnetbyaddr(unsigned long net, int type) {
struct net_data *net_data = init();
return (getnetbyaddr_p(net, type, net_data));
}
void
setnetent(int stayopen) {
struct net_data *net_data = init();
setnetent_p(stayopen, net_data);
}
void
endnetent() {
struct net_data *net_data = init();
endnetent_p(net_data);
}
/* Shared private. */
struct netent *
getnetent_p(struct net_data *net_data) {
struct irs_nw *nw;
if (!net_data || !(nw = net_data->nw))
return (NULL);
net_data->nww_last = (*nw->next)(nw);
net_data->nw_last = nw_to_net(net_data->nww_last, net_data);
return (net_data->nw_last);
}
struct netent *
getnetbyname_p(const char *name, struct net_data *net_data) {
struct irs_nw *nw;
struct netent *np;
char **nap;
if (!net_data || !(nw = net_data->nw))
return (NULL);
if (net_data->nw_stayopen && net_data->nw_last) {
if (!strcmp(net_data->nw_last->n_name, name))
return (net_data->nw_last);
for (nap = net_data->nw_last->n_aliases; nap && *nap; nap++)
if (!strcmp(name, *nap))
return (net_data->nw_last);
}
if ((np = fakeaddr(name, AF_INET, net_data)) != NULL)
return (np);
net_data->nww_last = (*nw->byname)(nw, name, AF_INET);
net_data->nw_last = nw_to_net(net_data->nww_last, net_data);
if (!net_data->nw_stayopen)
endnetent();
return (net_data->nw_last);
}
struct netent *
getnetbyaddr_p(unsigned long net, int type, struct net_data *net_data) {
struct irs_nw *nw;
u_char addr[4];
int bits;
if (!net_data || !(nw = net_data->nw))
return (NULL);
if (net_data->nw_stayopen && net_data->nw_last)
if (type == net_data->nw_last->n_addrtype &&
net == net_data->nw_last->n_net)
return (net_data->nw_last);
/* cannonize net(host order) */
if (net < 256UL) {
net <<= 24;
bits = 8;
} else if (net < 65536UL) {
net <<= 16;
bits = 16;
} else if (net < 16777216UL) {
net <<= 8;
bits = 24;
} else
bits = 32;
/* convert to net order */
addr[0] = (0xFF000000 & net) >> 24;
addr[1] = (0x00FF0000 & net) >> 16;
addr[2] = (0x0000FF00 & net) >> 8;
addr[3] = (0x000000FF & net);
/* reduce bits to as close to natural number as possible */
if ((bits == 32) && (addr[0] < 224) && (addr[3] == 0)) {
if ((addr[0] < 192) && (addr[2] == 0)) {
if ((addr[0] < 128) && (addr[1] == 0))
bits = 8;
else
bits = 16;
} else {
bits = 24;
}
}
net_data->nww_last = (*nw->byaddr)(nw, addr, bits, AF_INET);
net_data->nw_last = nw_to_net(net_data->nww_last, net_data);
if (!net_data->nw_stayopen)
endnetent();
return (net_data->nw_last);
}
void
setnetent_p(int stayopen, struct net_data *net_data) {
struct irs_nw *nw;
if (!net_data || !(nw = net_data->nw))
return;
freepvt(net_data);
(*nw->rewind)(nw);
net_data->nw_stayopen = (stayopen != 0);
if (stayopen == 0)
net_data_minimize(net_data);
}
void
endnetent_p(struct net_data *net_data) {
struct irs_nw *nw;
if ((net_data != NULL) && ((nw = net_data->nw) != NULL))
(*nw->minimize)(nw);
}
/* Private */
static struct net_data *
init() {
struct net_data *net_data;
if (!(net_data = net_data_init(NULL)))
goto error;
if (!net_data->nw) {
net_data->nw = (*net_data->irs->nw_map)(net_data->irs);
if (!net_data->nw || !net_data->res) {
error:
errno = EIO;
return (NULL);
}
(*net_data->nw->res_set)(net_data->nw, net_data->res, NULL);
}
return (net_data);
}
static void
freepvt(struct net_data *net_data) {
if (net_data->nw_data) {
free(net_data->nw_data);
net_data->nw_data = NULL;
}
}
static struct netent *
fakeaddr(const char *name, int af, struct net_data *net_data) {
struct pvt *pvt;
const char *cp;
u_long tmp;
if (af != AF_INET) {
/* XXX should support IPv6 some day */
errno = EAFNOSUPPORT;
RES_SET_H_ERRNO(net_data->res, NETDB_INTERNAL);
return (NULL);
}
if (!isascii((unsigned char)(name[0])) ||
!isdigit((unsigned char)(name[0])))
return (NULL);
for (cp = name; *cp; ++cp)
if (!isascii(*cp) || (!isdigit((unsigned char)*cp) && *cp != '.'))
return (NULL);
if (*--cp == '.')
return (NULL);
/* All-numeric, no dot at the end. */
tmp = inet_network(name);
if (tmp == INADDR_NONE) {
RES_SET_H_ERRNO(net_data->res, HOST_NOT_FOUND);
return (NULL);
}
/* Valid network number specified.
* Fake up a netent as if we'd actually
* done a lookup.
*/
freepvt(net_data);
net_data->nw_data = malloc(sizeof (struct pvt));
if (!net_data->nw_data) {
errno = ENOMEM;
RES_SET_H_ERRNO(net_data->res, NETDB_INTERNAL);
return (NULL);
}
pvt = net_data->nw_data;
strncpy(pvt->name, name, MAXDNAME);
pvt->name[MAXDNAME] = '\0';
pvt->netent.n_name = pvt->name;
pvt->netent.n_addrtype = AF_INET;
pvt->netent.n_aliases = pvt->aliases;
pvt->aliases[0] = NULL;
pvt->netent.n_net = tmp;
return (&pvt->netent);
}
static struct netent *
nw_to_net(struct nwent *nwent, struct net_data *net_data) {
struct pvt *pvt;
u_long addr = 0;
int i;
int msbyte;
if (!nwent || nwent->n_addrtype != AF_INET)
return (NULL);
freepvt(net_data);
net_data->nw_data = malloc(sizeof (struct pvt));
if (!net_data->nw_data) {
errno = ENOMEM;
RES_SET_H_ERRNO(net_data->res, NETDB_INTERNAL);
return (NULL);
}
pvt = net_data->nw_data;
pvt->netent.n_name = nwent->n_name;
pvt->netent.n_aliases = nwent->n_aliases;
pvt->netent.n_addrtype = nwent->n_addrtype;
/*%
* What this code does: Converts net addresses from network to host form.
*
* msbyte: the index of the most significant byte in the n_addr array.
*
* Shift bytes in significant order into addr. When all signicant
* bytes are in, zero out bits in the LSB that are not part of the network.
*/
msbyte = nwent->n_length / 8 +
((nwent->n_length % 8) != 0 ? 1 : 0) - 1;
for (i = 0; i <= msbyte; i++)
addr = (addr << 8) | ((unsigned char *)nwent->n_addr)[i];
i = (32 - nwent->n_length) % 8;
if (i != 0)
addr &= ~((1 << (i + 1)) - 1);
pvt->netent.n_net = addr;
return (&pvt->netent);
}
#endif /*__BIND_NOSTATIC*/
/*! \file */