dns/common/dns_common.c

	dns_common.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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
 */
/*
 *  dns_common.c
 *
 * Copyright (c) 1993,1998 by Sun Microsystems, Inc.
 * All rights reserved.
 */

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

#include "dns_common.h"

#define DNS_ALIASES 0
#define DNS_ADDRLIST    1
#define DNS_MAPDLIST    2

static int
dns_netdb_aliases(from_list, to_list, aliaspp, type, count, af_type)
    char    **from_list, **to_list, **aliaspp;
    int type, *count, af_type;
{
    char        *fstr;
    int     cnt = 0;
    size_t      len;

    *count = 0;
    if ((char *)to_list >= *aliaspp)
        return (NSS_STR_PARSE_ERANGE);

    for (fstr = from_list[cnt]; fstr != NULL; fstr = from_list[cnt]) {
        if (type == DNS_ALIASES)
            len = strlen(fstr) + 1;
        else
            len = (af_type == AF_INET) ? sizeof (struct in_addr)
                        : sizeof (struct in6_addr);
        *aliaspp -= len;
        to_list[cnt] = *aliaspp;
        if (*aliaspp <= (char *)&to_list[cnt+1])
            return (NSS_STR_PARSE_ERANGE);
        if (type == DNS_MAPDLIST) {
            struct in6_addr *addr6p = (struct in6_addr *) *aliaspp;

            (void) memset(addr6p, '\0', sizeof (struct in6_addr));
            (void) memcpy(&addr6p->s6_addr[12], fstr,
                    sizeof (struct in_addr));
            addr6p->s6_addr[10] = 0xffU;
            addr6p->s6_addr[11] = 0xffU;
            ++cnt;
        } else {
            (void) memcpy (*aliaspp, fstr, len);
            ++cnt;
        }
    }
    to_list[cnt] = NULL;

    *count = cnt;
    if (cnt == 0)
        return (NSS_STR_PARSE_PARSE);

    return (NSS_STR_PARSE_SUCCESS);
}


int
ent2result(he, argp, af_type)
    struct hostent      *he;
    nss_XbyY_args_t     *argp;
    int         af_type;
{
    char        *buffer, *limit;
    int     buflen = argp->buf.buflen;
    int     ret, count;
    size_t len;
    struct hostent  *host;
    struct in_addr  *addrp;
    struct in6_addr *addrp6;

    limit = argp->buf.buffer + buflen;
    host = (struct hostent *) argp->buf.result;
    buffer = argp->buf.buffer;

    /* h_addrtype and h_length */
    host->h_addrtype = af_type;
    host->h_length = (af_type == AF_INET) ? sizeof (struct in_addr)
                    : sizeof (struct in6_addr);

    /* h_name */
    len = strlen(he->h_name) + 1;
    host->h_name = buffer;
    if (host->h_name + len >= limit)
        return (NSS_STR_PARSE_ERANGE);
    (void) memcpy(host->h_name, he->h_name, len);
    buffer += len;

    /* h_addr_list */
    if (af_type == AF_INET) {
        addrp = (struct in_addr *) ROUND_DOWN(limit, sizeof (*addrp));
        host->h_addr_list = (char **)
                ROUND_UP(buffer, sizeof (char **));
        ret = dns_netdb_aliases(he->h_addr_list, host->h_addr_list,
            (char **)&addrp, DNS_ADDRLIST, &count, af_type);
        if (ret != NSS_STR_PARSE_SUCCESS)
            return (ret);
        /* h_aliases */
        host->h_aliases = host->h_addr_list + count + 1;
        ret = dns_netdb_aliases(he->h_aliases, host->h_aliases,
            (char **)&addrp, DNS_ALIASES, &count, af_type);
    } else {
        addrp6 = (struct in6_addr *)
            ROUND_DOWN(limit, sizeof (*addrp6));
        host->h_addr_list = (char **)
            ROUND_UP(buffer, sizeof (char **));
        if (he->h_addrtype == AF_INET && af_type == AF_INET6) {
            ret = dns_netdb_aliases(he->h_addr_list,
                host->h_addr_list, (char **)&addrp6,
                DNS_MAPDLIST, &count, af_type);
        } else {
            ret = dns_netdb_aliases(he->h_addr_list,
                host->h_addr_list, (char **)&addrp6,
                DNS_ADDRLIST, &count, af_type);
        }
        if (ret != NSS_STR_PARSE_SUCCESS)
            return (ret);
        /* h_aliases */
        host->h_aliases = host->h_addr_list + count + 1;
        ret = dns_netdb_aliases(he->h_aliases, host->h_aliases,
            (char **)&addrp6, DNS_ALIASES, &count, af_type);
    }
    if (ret == NSS_STR_PARSE_PARSE)
        ret = NSS_STR_PARSE_SUCCESS;

    return (ret);
}


nss_backend_t *
_nss_dns_constr(dns_backend_op_t ops[], int n_ops)
{
    dns_backend_ptr_t   be;

    if ((be = (dns_backend_ptr_t) malloc(sizeof (*be))) == 0)
        return (0);

    be->ops = ops;
    be->n_ops = n_ops;
    return ((nss_backend_t *) be);
}