1/*
2 * Copyright (c) 2002 Tim Rice.  All rights reserved.
3 * MAP_FAILED code by Solar Designer.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26/* $Id: xmmap.c,v 1.15 2009/02/16 04:21:40 djm Exp $ */
27
28#include "includes.h"
29
30#include <sys/types.h>
31#ifdef HAVE_SYS_MMAN_H
32#include <sys/mman.h>
33#endif
34#include <sys/stat.h>
35
36#ifdef HAVE_FCNTL_H
37# include <fcntl.h>
38#endif
39#include <errno.h>
40#include <stdarg.h>
41#include <stdlib.h>
42#include <string.h>
43#include <unistd.h>
44
45#include "log.h"
46
47void *
48xmmap(size_t size)
49{
50#ifdef HAVE_MMAP
51	void *address;
52
53# ifdef MAP_ANON
54	address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_ANON|MAP_SHARED,
55	    -1, (off_t)0);
56# else
57	address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_SHARED,
58	    open("/dev/zero", O_RDWR), (off_t)0);
59# endif
60
61#define MM_SWAP_TEMPLATE "/var/run/sshd.mm.XXXXXXXX"
62	if (address == (void *)MAP_FAILED) {
63		char tmpname[sizeof(MM_SWAP_TEMPLATE)] = MM_SWAP_TEMPLATE;
64		int tmpfd;
65		mode_t old_umask;
66
67		old_umask = umask(0177);
68		tmpfd = mkstemp(tmpname);
69		umask(old_umask);
70		if (tmpfd == -1)
71			fatal("mkstemp(\"%s\"): %s",
72			    MM_SWAP_TEMPLATE, strerror(errno));
73		unlink(tmpname);
74		if (ftruncate(tmpfd, size) != 0)
75			fatal("%s: ftruncate: %s", __func__, strerror(errno));
76		address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_SHARED,
77		    tmpfd, (off_t)0);
78		close(tmpfd);
79	}
80
81	return (address);
82#else
83	fatal("%s: UsePrivilegeSeparation=yes and Compression=yes not supported",
84	    __func__);
85#endif /* HAVE_MMAP */
86
87}
88
89