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 
  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"