xref: /titanic_41/usr/src/cmd/ssh/libopenbsd-compat/common/xmmap.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate  * Redistribution and use in source and binary forms, with or without
3*7c478bd9Sstevel@tonic-gate  * modification, are permitted provided that the following conditions
4*7c478bd9Sstevel@tonic-gate  * are met:
5*7c478bd9Sstevel@tonic-gate  * 1. Redistributions of source code must retain the above copyright
6*7c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer.
7*7c478bd9Sstevel@tonic-gate  * 2. Redistributions in binary form must reproduce the above copyright
8*7c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer in the
9*7c478bd9Sstevel@tonic-gate  *    documentation and/or other materials provided with the distribution.
10*7c478bd9Sstevel@tonic-gate  *
11*7c478bd9Sstevel@tonic-gate  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
12*7c478bd9Sstevel@tonic-gate  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
13*7c478bd9Sstevel@tonic-gate  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
14*7c478bd9Sstevel@tonic-gate  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
15*7c478bd9Sstevel@tonic-gate  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
16*7c478bd9Sstevel@tonic-gate  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
17*7c478bd9Sstevel@tonic-gate  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
18*7c478bd9Sstevel@tonic-gate  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
19*7c478bd9Sstevel@tonic-gate  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
20*7c478bd9Sstevel@tonic-gate  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
21*7c478bd9Sstevel@tonic-gate  */
22*7c478bd9Sstevel@tonic-gate 
23*7c478bd9Sstevel@tonic-gate #include "includes.h"
24*7c478bd9Sstevel@tonic-gate 
25*7c478bd9Sstevel@tonic-gate #ifdef HAVE_SYS_MMAN_H
26*7c478bd9Sstevel@tonic-gate #include <sys/mman.h>
27*7c478bd9Sstevel@tonic-gate #endif
28*7c478bd9Sstevel@tonic-gate 
29*7c478bd9Sstevel@tonic-gate #include "log.h"
30*7c478bd9Sstevel@tonic-gate 
xmmap(size_t size)31*7c478bd9Sstevel@tonic-gate void *xmmap(size_t size)
32*7c478bd9Sstevel@tonic-gate {
33*7c478bd9Sstevel@tonic-gate 	void *address;
34*7c478bd9Sstevel@tonic-gate 
35*7c478bd9Sstevel@tonic-gate #ifdef HAVE_MMAP
36*7c478bd9Sstevel@tonic-gate # ifdef MAP_ANON
37*7c478bd9Sstevel@tonic-gate 	address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_ANON|MAP_SHARED,
38*7c478bd9Sstevel@tonic-gate 	    -1, 0);
39*7c478bd9Sstevel@tonic-gate # else
40*7c478bd9Sstevel@tonic-gate 	address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_SHARED,
41*7c478bd9Sstevel@tonic-gate 	    open("/dev/zero", O_RDWR), 0);
42*7c478bd9Sstevel@tonic-gate # endif
43*7c478bd9Sstevel@tonic-gate 
44*7c478bd9Sstevel@tonic-gate #define MM_SWAP_TEMPLATE "/var/run/sshd.mm.XXXXXXXX"
45*7c478bd9Sstevel@tonic-gate 	if (address == MAP_FAILED) {
46*7c478bd9Sstevel@tonic-gate 		char tmpname[sizeof(MM_SWAP_TEMPLATE)] = MM_SWAP_TEMPLATE;
47*7c478bd9Sstevel@tonic-gate 		int tmpfd;
48*7c478bd9Sstevel@tonic-gate 
49*7c478bd9Sstevel@tonic-gate 		tmpfd = mkstemp(tmpname);
50*7c478bd9Sstevel@tonic-gate 		if (tmpfd == -1)
51*7c478bd9Sstevel@tonic-gate 			fatal("mkstemp(\"%s\"): %s",
52*7c478bd9Sstevel@tonic-gate 			    MM_SWAP_TEMPLATE, strerror(errno));
53*7c478bd9Sstevel@tonic-gate 		unlink(tmpname);
54*7c478bd9Sstevel@tonic-gate 		ftruncate(tmpfd, size);
55*7c478bd9Sstevel@tonic-gate 		address = mmap(NULL, size, PROT_WRITE|PROT_READ, MAP_SHARED,
56*7c478bd9Sstevel@tonic-gate 		    tmpfd, 0);
57*7c478bd9Sstevel@tonic-gate 		close(tmpfd);
58*7c478bd9Sstevel@tonic-gate 	}
59*7c478bd9Sstevel@tonic-gate 
60*7c478bd9Sstevel@tonic-gate 	return (address);
61*7c478bd9Sstevel@tonic-gate #else
62*7c478bd9Sstevel@tonic-gate 	fatal("%s: UsePrivilegeSeparation=yes and Compression=yes not supported",
63*7c478bd9Sstevel@tonic-gate 	    __func__);
64*7c478bd9Sstevel@tonic-gate #endif /* HAVE_MMAP */
65*7c478bd9Sstevel@tonic-gate 
66*7c478bd9Sstevel@tonic-gate }
67*7c478bd9Sstevel@tonic-gate 
68*7c478bd9Sstevel@tonic-gate 
69*7c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
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