1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * ++Copyright++ 1985, 1988, 1993
5 * -
6 * Copyright (c) 1985, 1988, 1993
7 *    The Regents of the University of California.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 * -
33 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
34 *
35 * Permission to use, copy, modify, and distribute this software for any
36 * purpose with or without fee is hereby granted, provided that the above
37 * copyright notice and this permission notice appear in all copies, and that
38 * the name of Digital Equipment Corporation not be used in advertising or
39 * publicity pertaining to distribution of the document or software without
40 * specific, written prior permission.
41 *
42 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
43 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
44 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
45 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
46 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
47 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
48 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
49 * SOFTWARE.
50 * -
51 * --Copyright--
52 */
53
54#include <sys/param.h>
55#include <sys/socket.h>
56#include <netinet/in.h>
57#include <arpa/inet.h>
58#include <arpa/nameser.h>
59
60#include <stdio.h>
61#include <string.h>
62#include <netdb.h>
63#include <resolv.h>
64#include <ctype.h>
65#include <syslog.h>
66#include "netdb_private.h"
67
68typedef union {
69	int32_t al;
70	char ac;
71} align;
72
73void
74_map_v4v6_address(const char *src, char *dst)
75{
76	/* Our caller may update in place. */
77	memmove(&dst[12], src, NS_INADDRSZ);
78	/* Mark this ipv6 addr as a mapped ipv4. */
79	memset(&dst[10], 0xff, 2);
80	memset(&dst[0], 0, 10);
81}
82
83void
84_map_v4v6_hostent(struct hostent *hp, char **bpp, char *ep) {
85	char **ap;
86
87	if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ)
88		return;
89	hp->h_addrtype = AF_INET6;
90	hp->h_length = IN6ADDRSZ;
91	for (ap = hp->h_addr_list; *ap; ap++) {
92		int i = (u_long)*bpp % sizeof(align);
93
94		if (i != 0)
95			i = sizeof(align) - i;
96
97		if ((ep - *bpp) < (i + IN6ADDRSZ)) {
98			/* Out of memory.  Truncate address list here. */
99			*ap = NULL;
100			return;
101		}
102		*bpp += i;
103		_map_v4v6_address(*ap, *bpp);
104		*ap = *bpp;
105		*bpp += IN6ADDRSZ;
106	}
107}
108