xref: /titanic_41/usr/src/cmd/ssh/libopenbsd-compat/common/xmmap.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * Redistribution and use in source and binary forms, with or without
3  * modification, are permitted provided that the following conditions
4  * are met:
5  * 1. Redistributions of source code must retain the above copyright
6  *    notice, this list of conditions and the following disclaimer.
7  * 2. Redistributions in binary form must reproduce the above copyright
8  *    notice, this list of conditions and the following disclaimer in the
9  *    documentation and/or other materials provided with the distribution.
10  *
11  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
12  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
13  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
14  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
15  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
16  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
17  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
18  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
19  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
20  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22 
23 #include "includes.h"
24 
25 #ifdef HAVE_SYS_MMAN_H
26 #include <sys/mman.h>
27 #endif
28 
29 #include "log.h"
30 
xmmap(size_t size)31 void *xmmap(size_t size)
32 {
33 	void *address;
34 
35 #ifdef HAVE_MMAP
36 # ifdef MAP_ANON
37 	address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_ANON|MAP_SHARED,
38 	    -1, 0);
39 # else
40 	address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_SHARED,
41 	    open("/dev/zero", O_RDWR), 0);
42 # endif
43 
44 #define MM_SWAP_TEMPLATE "/var/run/sshd.mm.XXXXXXXX"
45 	if (address == MAP_FAILED) {
46 		char tmpname[sizeof(MM_SWAP_TEMPLATE)] = MM_SWAP_TEMPLATE;
47 		int tmpfd;
48 
49 		tmpfd = mkstemp(tmpname);
50 		if (tmpfd == -1)
51 			fatal("mkstemp(\"%s\"): %s",
52 			    MM_SWAP_TEMPLATE, strerror(errno));
53 		unlink(tmpname);
54 		ftruncate(tmpfd, size);
55 		address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_SHARED,
56 		    tmpfd, 0);
57 		close(tmpfd);
58 	}
59 
60 	return (address);
61 #else
62 	fatal("%s: UsePrivilegeSeparation=yes and Compression=yes not supported",
63 	    __func__);
64 #endif /* HAVE_MMAP */
65 
66 }
67 
68 
69 #pragma ident	"%Z%%M%	%I%	%E% SMI"
70