lib/lwres/getipnode.c

	getipnode.c revision 91cd0f93ad34d23e8b09dca337120f64fbe8f0a1
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt/*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * Copyright (C) 1999-2001  Internet Software Consortium.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * Permission to use, copy, modify, and distribute this software for any
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * purpose with or without fee is hereby granted, provided that the above
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * copyright notice and this permission notice appear in all copies.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt */
3d17a3ba61a303d5c4d9867068d0fbe9f24d2988Mark Andrews
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt/* $Id: getipnode.c,v 1.32 2001/11/27 01:56:28 gson Exp $ */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include <config.h>
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include <stdio.h>
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include <stdlib.h>
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include <string.h>
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include <lwres/lwres.h>
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include <lwres/net.h>
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include <lwres/netdb.h>    /* XXX #include <netdb.h> */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#include "assert_p.h"
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#ifndef INADDRSZ
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#define INADDRSZ 4
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#endif
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#ifndef IN6ADDRSZ
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#define IN6ADDRSZ 16
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#endif
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#ifdef LWRES_PLATFORM_NEEDIN6ADDRANY
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan HuntLIBLWRES_EXTERNAL_DATA const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#endif
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#ifndef IN6_IS_ADDR_V4COMPAT
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstatic const unsigned char in6addr_compat[12] = {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt};
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#define IN6_IS_ADDR_V4COMPAT(x) (!memcmp((x)->s6_addr, in6addr_compat, 12) && \
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                                 ((x)->s6_addr[12] != 0 || \
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                                  (x)->s6_addr[13] != 0 || \
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                                  (x)->s6_addr[14] != 0 || \
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                                   ((x)->s6_addr[15] != 0 && \
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                                    (x)->s6_addr[15] != 1)))
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#endif
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#ifndef IN6_IS_ADDR_V4MAPPED
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#define IN6_IS_ADDR_V4MAPPED(x) (!memcmp((x)->s6_addr, in6addr_mapped, 12))
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt#endif
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstatic const unsigned char in6addr_mapped[12] = {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        0, 0, 0, 0,  0, 0, 0, 0,  0, 0, 0xff, 0xff
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt};
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt/***
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt ***    Forward declarations.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt ***/
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstatic int
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntscan_interfaces(int *, int *);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstatic struct hostent *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntcopyandmerge(struct hostent *, struct hostent *, int, int *);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstatic struct hostent *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunthostfromaddr(lwres_gnbaresponse_t *addr, int af, const void *src);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstatic struct hostent *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunthostfromname(lwres_gabnresponse_t *name, int af);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt/***
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt ***    Public functions.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt ***/
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt/*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *  AI_V4MAPPED + AF_INET6
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *  If no IPv6 address then a query for IPv4 and map returned values.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *  AI_ALL + AI_V4MAPPED + AF_INET6
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *  Return IPv6 and IPv4 mapped.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *  AI_ADDRCONFIG
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *  Only return IPv6 / IPv4 address if there is an interface of that
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *  type active.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstruct hostent *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntlwres_getipnodebyname(const char *name, int af, int flags, int *error_num) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    int have_v4 = 1, have_v6 = 1;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    struct in_addr in4;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    struct in6_addr in6;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    struct hostent he, *he1 = NULL, *he2 = NULL, *he3 = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    int v4 = 0, v6 = 0;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    int tmp_err;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    lwres_context_t *lwrctx = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    lwres_gabnresponse_t *by = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    int n;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * If we care about active interfaces then check.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if ((flags & AI_ADDRCONFIG) != 0)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (scan_interfaces(&have_v4, &have_v6) == -1) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /* Check for literal address. */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if ((v4 = lwres_net_pton(AF_INET, name, &in4)) != 1)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        v6 = lwres_net_pton(AF_INET6, name, &in6);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * Impossible combination?
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if ((af == AF_INET6 && (flags & AI_V4MAPPED) == 0 && v4 == 1) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (af == AF_INET && v6 == 1) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (have_v4 == 0 && v4 == 1) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (have_v6 == 0 && v6 == 1) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (have_v4 == 0 && af == AF_INET) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (have_v6 == 0 && af == AF_INET6 &&
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt         (((flags & AI_V4MAPPED) != 0 && have_v4) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt          (flags & AI_V4MAPPED) == 0))) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = HOST_NOT_FOUND;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * Literal address?
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (v4 == 1 || v6 == 1) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        char *addr_list[2];
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        char *aliases[1];
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        union {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            const char *const_name;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            char *deconst_name;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        } u;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        u.const_name = name;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_name = u.deconst_name;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_addr_list = addr_list;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_addr_list[0] = (v4 == 1) ? (char *)&in4 : (char *)&in6;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_addr_list[1] = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_aliases = aliases;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_aliases[0] = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_length = (v4 == 1) ? INADDRSZ : IN6ADDRSZ;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he.h_addrtype = (v4 == 1) ? AF_INET : AF_INET6;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        return (copyandmerge(&he, NULL, af, error_num));
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    n = lwres_context_create(&lwrctx, NULL, NULL, NULL, 0);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (n != 0) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        goto cleanup;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    (void) lwres_conf_parse(lwrctx, lwres_resolv_conf);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    tmp_err = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (have_v6 && af == AF_INET6) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        n = lwres_getaddrsbyname(lwrctx, name, LWRES_ADDRTYPE_V6, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (n == 0) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            he1 = hostfromname(by, AF_INET6);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            lwres_gabnresponse_free(lwrctx, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            if (he1 == NULL) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                goto cleanup;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        } else {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            tmp_err = HOST_NOT_FOUND;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (have_v4 &&
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        ((af == AF_INET) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt         (af == AF_INET6 && (flags & AI_V4MAPPED) != 0 &&
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt          (he1 == NULL || (flags & AI_ALL) != 0)))) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        n = lwres_getaddrsbyname(lwrctx, name, LWRES_ADDRTYPE_V4, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (n == 0) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            he2 = hostfromname(by, AF_INET);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            lwres_gabnresponse_free(lwrctx, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            if (he2 == NULL) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                goto cleanup;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        } else if (he1 == NULL) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            if (n == LWRES_R_NOTFOUND)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                *error_num = HOST_NOT_FOUND;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            else
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            goto cleanup;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    } else
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = tmp_err;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    he3 = copyandmerge(he1, he2, af, error_num);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt cleanup:
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (he1 != NULL)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_freehostent(he1);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (he2 != NULL)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_freehostent(he2);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (lwrctx != NULL) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_conf_clear(lwrctx);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_context_destroy(&lwrctx);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    return (he3);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt}
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntstruct hostent *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntlwres_getipnodebyaddr(const void *src, size_t len, int af, int *error_num) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    struct hostent *he1, *he2;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    lwres_context_t *lwrctx = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    lwres_gnbaresponse_t *by = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    lwres_result_t n;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    union {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        const void *konst;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        struct in6_addr *in6;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    } u;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * Sanity checks.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (src == NULL) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    switch (af) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    case AF_INET:
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (len != INADDRSZ) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        break;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    case AF_INET6:
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (len != IN6ADDRSZ) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        break;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    default:
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * The de-"const"-ing game is done because at least one
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * vendor's system (RedHat 6.0) defines the IN6_IS_ADDR_*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * macros in such a way that they discard the const with
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * internal casting, and gcc ends up complaining.  Rather
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * than replacing their own (possibly optimized) definitions
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * with our own, cleanly discarding the const is the easiest
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * thing to do.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    u.konst = src;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * Look up IPv4 and IPv4 mapped/compatible addresses.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if ((af == AF_INET6 && IN6_IS_ADDR_V4COMPAT(u.in6)) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (af == AF_INET6 && IN6_IS_ADDR_V4MAPPED(u.in6)) ||
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (af == AF_INET)) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        const unsigned char *cp = src;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (af == AF_INET6)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            cp += 12;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        n = lwres_context_create(&lwrctx, NULL, NULL, NULL, 0);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (n == LWRES_R_SUCCESS)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            (void) lwres_conf_parse(lwrctx, lwres_resolv_conf);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (n == LWRES_R_SUCCESS)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            n = lwres_getnamebyaddr(lwrctx, LWRES_ADDRTYPE_V4,
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                        INADDRSZ, cp, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (n != LWRES_R_SUCCESS) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            lwres_conf_clear(lwrctx);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            lwres_context_destroy(&lwrctx);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            if (n == LWRES_R_NOTFOUND)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                *error_num = HOST_NOT_FOUND;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            else
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he1 = hostfromaddr(by, AF_INET, cp);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_gnbaresponse_free(lwrctx, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_conf_clear(lwrctx);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_context_destroy(&lwrctx);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (af != AF_INET6)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            return (he1);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt         * Convert from AF_INET to AF_INET6.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt         */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        he2 = copyandmerge(he1, NULL, af, error_num);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        lwres_freehostent(he1);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        if (he2 == NULL)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt            return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt         * Restore original address.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt         */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        memcpy(he2->h_addr, src, len);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        return (he2);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    /*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     * Lookup IPv6 address.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt     */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (memcmp(src, &in6addr_any, IN6ADDRSZ) == 0) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = HOST_NOT_FOUND;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    n = lwres_context_create(&lwrctx, NULL, NULL, NULL, 0);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (n == LWRES_R_SUCCESS)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        (void) lwres_conf_parse(lwrctx, lwres_resolv_conf);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (n == LWRES_R_SUCCESS)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        n = lwres_getnamebyaddr(lwrctx, LWRES_ADDRTYPE_V6, IN6ADDRSZ,
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt                    src, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (n != 0) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = HOST_NOT_FOUND;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        return (NULL);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    he1 = hostfromaddr(by, AF_INET6, src);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    lwres_gnbaresponse_free(lwrctx, &by);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    if (he1 == NULL)
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *error_num = NO_RECOVERY;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    lwres_context_destroy(&lwrctx);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    return (he1);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt}
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntvoid
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntlwres_freehostent(struct hostent *he) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    char **cpp;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    int names = 1;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    int addresses = 1;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    free(he->h_name);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    cpp = he->h_addr_list;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    while (*cpp != NULL) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        free(*cpp);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        *cpp = NULL;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        cpp++;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        addresses++;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    cpp = he->h_aliases;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    while (*cpp != NULL) {
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        free(*cpp);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        cpp++;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt        names++;
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    }
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    free(he->h_aliases);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    free(he->h_addr_list);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt    free(he);
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt}
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt/*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * Private
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt */
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt/*
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * Scan the interface table and set have_v4 and have_v6 depending
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * upon whether there are IPv4 and IPv6 interface addresses.
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt *
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Hunt * Returns:
3d17a3ba61a303d5c4d9867068d0fbe9f24d2988Mark Andrews *  0 on success
3d17a3ba61a303d5c4d9867068d0fbe9f24d2988Mark Andrews *  -1 on failure.
3d17a3ba61a303d5c4d9867068d0fbe9f24d2988Mark Andrews */
3d17a3ba61a303d5c4d9867068d0fbe9f24d2988Mark Andrews
3d17a3ba61a303d5c4d9867068d0fbe9f24d2988Mark Andrewsstatic int
cfb1587eb9a6dc6d1d36ea0344e1b20068b81e88Evan Huntscan_interfaces(int *have_v4, int *have_v6) {
#if 1
    *have_v4 = *have_v6 = 1;
    return (0);
#else
    struct ifconf ifc;
    struct ifreq ifreq;
    struct in_addr in4;
    struct in6_addr in6;
    char *buf = NULL, *cp, *cplim;
    static int bufsiz = 4095;
    int s, cpsize, n;

    /*
     * Set to zero.  Used as loop terminators below.
     */
    *have_v4 = *have_v6 = 0;

    /*
     * Get interface list from system.
     */
    if ((s = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
        goto err_ret;

    /*
     * Grow buffer until large enough to contain all interface
     * descriptions.
     */
    for (;;) {
        buf = malloc(bufsiz);
        if (buf == NULL)
            goto err_ret;
        ifc.ifc_len = bufsiz;
        ifc.ifc_buf = buf;
#ifdef IRIX_EMUL_IOCTL_SIOCGIFCONF
        /*
         * This is a fix for IRIX OS in which the call to ioctl with
         * the flag SIOCGIFCONF may not return an entry for all the
         * interfaces like most flavors of Unix.
         */
        if (emul_ioctl(&ifc) >= 0)
            break;
#else
        if ((n = ioctl(s, SIOCGIFCONF, (char *)&ifc)) != -1) {
            /*
             * Some OS's just return what will fit rather
             * than set EINVAL if the buffer is too small
             * to fit all the interfaces in.  If
             * ifc.ifc_len is too near to the end of the
             * buffer we will grow it just in case and
             * retry.
             */
            if (ifc.ifc_len + 2 * sizeof(ifreq) < bufsiz)
                break;
        }
#endif
        if ((n == -1) && errno != EINVAL)
            goto err_ret;

        if (bufsiz > 1000000)
            goto err_ret;

        free(buf);
        bufsiz += 4096;
    }

    /*
     * Parse system's interface list.
     */
    cplim = buf + ifc.ifc_len;    /* skip over if's with big ifr_addr's */
    for (cp = buf;
         (*have_v4 == 0 || *have_v6 == 0) && cp < cplim;
         cp += cpsize) {
        memcpy(&ifreq, cp, sizeof(ifreq));
#ifdef LWRES_PLATFORM_HAVESALEN
#ifdef FIX_ZERO_SA_LEN
        if (ifreq.ifr_addr.sa_len == 0)
            ifreq.ifr_addr.sa_len = IN6ADDRSZ;
#endif
#ifdef HAVE_MINIMUM_IFREQ
        cpsize = sizeof(ifreq);
        if (ifreq.ifr_addr.sa_len > sizeof(struct sockaddr))
            cpsize += (int)ifreq.ifr_addr.sa_len -
                (int)(sizeof(struct sockaddr));
#else
        cpsize = sizeof(ifreq.ifr_name) + ifreq.ifr_addr.sa_len;
#endif /* HAVE_MINIMUM_IFREQ */
#elif defined SIOCGIFCONF_ADDR
        cpsize = sizeof(ifreq);
#else
        cpsize = sizeof(ifreq.ifr_name);
        /* XXX maybe this should be a hard error? */
        if (ioctl(s, SIOCGIFADDR, (char *)&ifreq) < 0)
            continue;
#endif /* LWRES_PLATFORM_HAVESALEN */
        switch (ifreq.ifr_addr.sa_family) {
        case AF_INET:
            if (*have_v4 == 0) {
                memcpy(&in4,
                       &((struct sockaddr_in *)
                       &ifreq.ifr_addr)->sin_addr,
                       sizeof(in4));
                if (in4.s_addr == INADDR_ANY)
                    break;
                n = ioctl(s, SIOCGIFFLAGS, (char *)&ifreq);
                if (n < 0)
                    break;
                if ((ifreq.ifr_flags & IFF_UP) == 0)
                    break;
                *have_v4 = 1;
            }
            break;
        case AF_INET6:
            if (*have_v6 == 0) {
                memcpy(&in6,
                       &((struct sockaddr_in6 *)
                       &ifreq.ifr_addr)->sin6_addr,
                       sizeof(in6));
                if (memcmp(&in6, &in6addr_any,
                       sizeof(in6)) == 0)
                    break;
                n = ioctl(s, SIOCGIFFLAGS, (char *)&ifreq);
                if (n < 0)
                    break;
                if ((ifreq.ifr_flags & IFF_UP) == 0)
                    break;
                *have_v6 = 1;
            }
            break;
        }
    }
    if (buf != NULL)
        free(buf);
    close(s);
    return (0);
 err_ret:
    if (buf != NULL)
        free(buf);
    if (s != -1)
        close(s);
    return (-1);
#endif
}

static struct hostent *
copyandmerge(struct hostent *he1, struct hostent *he2, int af, int *error_num)
{
    struct hostent *he = NULL;
    int addresses = 1;  /* NULL terminator */
    int names = 1;      /* NULL terminator */
    int len = 0;
    char **cpp, **npp;

    /*
     * Work out array sizes.
     */
    if (he1 != NULL) {
        cpp = he1->h_addr_list;
        while (*cpp != NULL) {
            addresses++;
            cpp++;
        }
        cpp = he1->h_aliases;
        while (*cpp != NULL) {
            names++;
            cpp++;
        }
    }

    if (he2 != NULL) {
        cpp = he2->h_addr_list;
        while (*cpp != NULL) {
            addresses++;
            cpp++;
        }
        if (he1 == NULL) {
            cpp = he2->h_aliases;
            while (*cpp != NULL) {
                names++;
                cpp++;
            }
        }
    }

    if (addresses == 1) {
        *error_num = NO_ADDRESS;
        return (NULL);
    }

    he = malloc(sizeof(*he));
    if (he == NULL)
        goto no_recovery;

    he->h_addr_list = malloc(sizeof(char *) * (addresses));
    if (he->h_addr_list == NULL)
        goto cleanup0;
    memset(he->h_addr_list, 0, sizeof(char *) * (addresses));

    /*
     * Copy addresses.
     */
    npp = he->h_addr_list;
    if (he1 != NULL) {
        cpp = he1->h_addr_list;
        while (*cpp != NULL) {
            *npp = malloc((af == AF_INET) ? INADDRSZ : IN6ADDRSZ);
            if (*npp == NULL)
                goto cleanup1;
            /*
             * Convert to mapped if required.
             */
            if (af == AF_INET6 && he1->h_addrtype == AF_INET) {
                memcpy(*npp, in6addr_mapped,
                       sizeof(in6addr_mapped));
                memcpy(*npp + sizeof(in6addr_mapped), *cpp,
                       INADDRSZ);
            } else {
                memcpy(*npp, *cpp,
                       (af == AF_INET) ? INADDRSZ : IN6ADDRSZ);
            }
            cpp++;
            npp++;
        }
    }

    if (he2 != NULL) {
        cpp = he2->h_addr_list;
        while (*cpp != NULL) {
            *npp = malloc((af == AF_INET) ? INADDRSZ : IN6ADDRSZ);
            if (*npp == NULL)
                goto cleanup1;
            /*
             * Convert to mapped if required.
             */
            if (af == AF_INET6 && he2->h_addrtype == AF_INET) {
                memcpy(*npp, in6addr_mapped,
                       sizeof(in6addr_mapped));
                memcpy(*npp + sizeof(in6addr_mapped), *cpp,
                       INADDRSZ);
            } else {
                memcpy(*npp, *cpp,
                       (af == AF_INET) ? INADDRSZ : IN6ADDRSZ);
            }
            cpp++;
            npp++;
        }
    }

    he->h_aliases = malloc(sizeof(char *) * (names));
    if (he->h_aliases == NULL)
        goto cleanup1;
    memset(he->h_aliases, 0, sizeof(char *) * (names));

    /*
     * Copy aliases.
     */
    npp = he->h_aliases;
    cpp = (he1 != NULL) ? he1->h_aliases : he2->h_aliases;
    while (*cpp != NULL) {
        len = strlen (*cpp) + 1;
        *npp = malloc(len);
        if (*npp == NULL)
            goto cleanup2;
        strcpy(*npp, *cpp);
        npp++;
        cpp++;
    }

    /*
     * Copy hostname.
     */
    he->h_name = malloc(strlen((he1 != NULL) ?
                he1->h_name : he2->h_name) + 1);
    if (he->h_name == NULL)
        goto cleanup2;
    strcpy(he->h_name, (he1 != NULL) ? he1->h_name : he2->h_name);

    /*
     * Set address type and length.
     */
    he->h_addrtype = af;
    he->h_length = (af == AF_INET) ? INADDRSZ : IN6ADDRSZ;
    return (he);

 cleanup2:
    cpp = he->h_aliases;
    while (*cpp != NULL) {
        free(*cpp);
        cpp++;
    }
    free(he->h_aliases);

 cleanup1:
    cpp = he->h_addr_list;
    while (*cpp != NULL) {
        free(*cpp);
        *cpp = NULL;
        cpp++;
    }
    free(he->h_addr_list);

 cleanup0:
    free(he);

 no_recovery:
    *error_num = NO_RECOVERY;
    return (NULL);
}

static struct hostent *
hostfromaddr(lwres_gnbaresponse_t *addr, int af, const void *src) {
    struct hostent *he;
    int i;

    he = malloc(sizeof(*he));
    if (he == NULL)
        goto cleanup;
    memset(he, 0, sizeof(*he));

    /*
     * Set family and length.
     */
    he->h_addrtype = af;
    switch (af) {
    case AF_INET:
        he->h_length = INADDRSZ;
        break;
    case AF_INET6:
        he->h_length = IN6ADDRSZ;
        break;
    default:
        INSIST(0);
    }

    /*
     * Copy name.
     */
    he->h_name = strdup(addr->realname);
    if (he->h_name == NULL)
        goto cleanup;

    /*
     * Copy aliases.
     */
    he->h_aliases = malloc(sizeof(char *) * (addr->naliases + 1));
    if (he->h_aliases == NULL)
        goto cleanup;
    for (i = 0; i < addr->naliases; i++) {
        he->h_aliases[i] = strdup(addr->aliases[i]);
        if (he->h_aliases[i] == NULL)
            goto cleanup;
    }
    he->h_aliases[i] = NULL;

    /*
     * Copy address.
     */
    he->h_addr_list = malloc(sizeof(char *) * 2);
    if (he->h_addr_list == NULL)
        goto cleanup;
    he->h_addr_list[0] = malloc(he->h_length);
    if (he->h_addr_list[0] == NULL)
        goto cleanup;
    memcpy(he->h_addr_list[0], src, he->h_length);
    he->h_addr_list[1] = NULL;
    return (he);

 cleanup:
    if (he != NULL && he->h_addr_list != NULL) {
        for (i = 0; he->h_addr_list[i] != NULL; i++)
            free(he->h_addr_list[i]);
        free(he->h_addr_list);
    }
    if (he != NULL && he->h_aliases != NULL) {
        for (i = 0; he->h_aliases[i] != NULL; i++)
            free(he->h_aliases[i]);
        free(he->h_aliases);
    }
    if (he != NULL && he->h_name != NULL)
        free(he->h_name);
    if (he != NULL)
        free(he);
    return (NULL);
}

static struct hostent *
hostfromname(lwres_gabnresponse_t *name, int af) {
    struct hostent *he;
    int i;
    lwres_addr_t *addr;

    he = malloc(sizeof(*he));
    if (he == NULL)
        goto cleanup;
    memset(he, 0, sizeof(*he));

    /*
     * Set family and length.
     */
    he->h_addrtype = af;
    switch (af) {
    case AF_INET:
        he->h_length = INADDRSZ;
        break;
    case AF_INET6:
        he->h_length = IN6ADDRSZ;
        break;
    default:
        INSIST(0);
    }

    /*
     * Copy name.
     */
    he->h_name = strdup(name->realname);
    if (he->h_name == NULL)
        goto cleanup;

    /*
     * Copy aliases.
     */
    he->h_aliases = malloc(sizeof(char *) * (name->naliases + 1));
    for (i = 0; i < name->naliases; i++) {
        he->h_aliases[i] = strdup(name->aliases[i]);
        if (he->h_aliases[i] == NULL)
            goto cleanup;
    }
    he->h_aliases[i] = NULL;

    /*
     * Copy addresses.
     */
    he->h_addr_list = malloc(sizeof(char *) * (name->naddrs + 1));
    addr = LWRES_LIST_HEAD(name->addrs);
    i = 0;
    while (addr != NULL) {
        he->h_addr_list[i] = malloc(he->h_length);
        if (he->h_addr_list[i] == NULL)
            goto cleanup;
        memcpy(he->h_addr_list[i], addr->address, he->h_length);
        addr = LWRES_LIST_NEXT(addr, link);
        i++;
    }
    he->h_addr_list[i] = NULL;
    return (he);

 cleanup:
    if (he != NULL && he->h_addr_list != NULL) {
        for (i = 0; he->h_addr_list[i] != NULL; i++)
            free(he->h_addr_list[i]);
        free(he->h_addr_list);
    }
    if (he != NULL && he->h_aliases != NULL) {
        for (i = 0; he->h_aliases[i] != NULL; i++)
            free(he->h_aliases[i]);
        free(he->h_aliases);
    }
    if (he != NULL && he->h_name != NULL)
        free(he->h_name);
    if (he != NULL)
        free(he);
    return (NULL);
}