files/common/netmasks.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 (c) 1995, 2011, Oracle and/or its affiliates. All rights reserved.
 *
 * files/netmasks.c -- "files" backend for nsswitch "netmasks" database
 */

/*
 * All routines necessary to deal with the file /etc/inet/netmasks.  The file
 * contains mappings from 32 bit network internet addresses to their
 * corresponding 32 bit mask internet addresses. The addresses are in dotted
 * internet address form.
 */

#include "files_common.h"
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <nss_dbdefs.h>
#include <ctype.h>

/*
 * Validate 'files' netmasks entry. The comparison objects are in IPv4
 * internet address format.
 */
static int
check_addr(nss_XbyY_args_t *argp, const char *line, int linelen)
{
    const char  *limit, *linep, *addrstart;
    int     addrlen;
    char        addrbuf[NSS_LINELEN_NETMASKS];
    struct in_addr  lineaddr, argsaddr;

    linep = line;
    limit = line + linelen;

    /* skip leading spaces */
    while (linep < limit && isspace(*linep))
        linep++;

    addrstart = linep;
    while (linep < limit && !isspace(*linep))
        linep++;
    if (linep == limit)
        return (0);
    addrlen = linep - addrstart;
    if (addrlen < sizeof (addrbuf)) {
        (void) memcpy(addrbuf, addrstart, addrlen);
        addrbuf[addrlen] = '\0';
        if ((lineaddr.s_addr = inet_addr(addrbuf)) ==
            (in_addr_t)0xffffffffU)
            return (0);
        if ((argsaddr.s_addr = inet_addr(argp->key.name))
            == (in_addr_t)0xffffffffU)
            return (0);
        return (lineaddr.s_addr == argsaddr.s_addr);
    }
    return (0);
}

static nss_status_t
getbynet(be, a)
    files_backend_ptr_t be;
    void            *a;
{
    nss_XbyY_args_t     *argp = (nss_XbyY_args_t *)a;
    nss_status_t        res;
    char            tmpbuf[NSS_LINELEN_NETMASKS];

    /*
     * use the buffer passed in if result is to be returned
     * in /etc file format
     */
    if (argp->buf.result != NULL) {
        argp->buf.buffer = tmpbuf;
        argp->buf.buflen = NSS_LINELEN_NETMASKS;
    }
    res = _nss_files_XY_all(be, argp, 1, argp->key.name, check_addr);
    if (argp->buf.result != NULL) {
        argp->buf.buffer = NULL;
        argp->buf.buflen = 0;
    } else {
        /* the frontend expects the netmask data only */
        if (res == NSS_SUCCESS)  {
            char    *m;
            char    *s = (char *)argp->returnval;
            int l = 0;

            m = s + argp->returnlen - 1;

            /* skip trailing spaces */
            while (s < m && isspace(*m))
                m--;

            for (; s <= m; m--) {
                if (isspace(*m))
                    break;
                l++;
            }
            m++;
            (void) memmove(argp->returnval, m, l);
            argp->returnlen = l;
            *(s + l) = '\0';
        }
    }

    return (res);
}

static files_backend_op_t netmasks_ops[] = {
    _nss_files_destr,
    getbynet
};

/*ARGSUSED*/
nss_backend_t *
_nss_files_netmasks_constr(dummy1, dummy2, dummy3)
    const char  *dummy1, *dummy2, *dummy3;
{
    return (_nss_files_constr(netmasks_ops,
        sizeof (netmasks_ops) / sizeof (netmasks_ops[0]),
        _PATH_NETMASKS, NSS_LINELEN_NETMASKS, NULL, 0));
}