nis/common/getnetent.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/*
 *  nis/getnetent.c -- "nis" backend for nsswitch "networks" database
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include "nis_common.h"
#include <synch.h>
#include <netdb.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>

static int nettoa(int anet, char *buf, int buflen, char **pnull);

static nss_status_t
getbyname(be, a)
    nis_backend_ptr_t   be;
    void            *a;
{
    nss_XbyY_args_t     *argp = (nss_XbyY_args_t *)a;

    return (_nss_nis_lookup(be, argp, 1, "networks.byname",
        argp->key.name, 0));
}

static nss_status_t
getbyaddr(be, a)
    nis_backend_ptr_t   be;
    void            *a;
{
    nss_XbyY_args_t     *argp = (nss_XbyY_args_t *)a;
    char            addrstr[16];
    char            *pnull;
    nss_status_t        rc;

    if (nettoa((int)argp->key.netaddr.net, addrstr, 16, &pnull) != 0)
        return (NSS_UNAVAIL);   /* it's really ENOMEM */
    rc = _nss_nis_lookup(be, argp, 1, "networks.byaddr", addrstr, 0);

    /*
     * if not found, try again with the untruncated address string
     * that has the trailing zero(s)
     */
    if (rc == NSS_NOTFOUND && pnull != NULL) {
        *pnull = '.';
        rc = _nss_nis_lookup(be, argp, 1, "networks.byaddr",
            addrstr, 0);
    }
    return (rc);
}

static nis_backend_op_t net_ops[] = {
    _nss_nis_destr,
    _nss_nis_endent,
    _nss_nis_setent,
    _nss_nis_getent_netdb,
    getbyname,
    getbyaddr
};

/*ARGSUSED*/
nss_backend_t *
_nss_nis_networks_constr(dummy1, dummy2, dummy3)
    const char  *dummy1, *dummy2, *dummy3;
{
    return (_nss_nis_constr(net_ops,
                sizeof (net_ops) / sizeof (net_ops[0]),
                "networks.byaddr"));
}

/*
 * Takes an unsigned integer in host order, and returns a printable
 * string for it as a network number.  To allow for the possibility of
 * naming subnets, only trailing dot-zeros are truncated. The location
 * where the string is truncated (or set to '\0') is returned in *pnull.
 */
static int
nettoa(int anet, char *buf, int buflen, char **pnull)
{
    char *p;
    struct in_addr in;
    int addr;

    *pnull = NULL;

    if (buf == 0)
        return (1);
    in = inet_makeaddr(anet, INADDR_ANY);
    addr = in.s_addr;
    (void) strncpy(buf, inet_ntoa(in), buflen);
    if ((IN_CLASSA_HOST & htonl(addr)) == 0) {
        p = strchr(buf, '.');
        if (p == NULL)
            return (1);
        *p = 0;
        *pnull = p;
    } else if ((IN_CLASSB_HOST & htonl(addr)) == 0) {
        p = strchr(buf, '.');
        if (p == NULL)
            return (1);
        p = strchr(p+1, '.');
        if (p == NULL)
            return (1);
        *p = 0;
        *pnull = p;
    } else if ((IN_CLASSC_HOST & htonl(addr)) == 0) {
        p = strrchr(buf, '.');
        if (p == NULL)
            return (1);
        *p = 0;
        *pnull = p;
    }
    return (0);
}