package/cfgfs/src/sys_bsd.c

   1 /* $MirOS: contrib/hosted/fwcf/sys_bsd.c,v 1.4 2007/03/13 18:14:30 tg Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2006, 2007
   5  *      Thorsten Glaser <tg@mirbsd.de>
   6  *
   7  * Provided that these terms and disclaimer and all copyright notices
   8  * are retained or reproduced in an accompanying document, permission
   9  * is granted to deal in this work without restriction, including un-
  10  * limited rights to use, publicly perform, distribute, sell, modify,
  11  * merge, give away, or sublicence.
  12  *
  13  * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
  14  * the utmost extent permitted by applicable law, neither express nor
  15  * implied; without malicious intent or gross negligence. In no event
  16  * may a licensor, author or contributor be held liable for indirect,
  17  * direct, other damage, loss, or other issues arising in any way out
  18  * of dealing in the work, even if advised of the possibility of such
  19  * damage or existence of a defect, except proven that it results out
  20  * of said person's immediate fault when using the work as intended.
  21  */
  22
  23 #include <fcntl.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26
  27 #include "defs.h"
  28 #include "sysdeps.h"
  29
  30 __RCSID("$MirOS: contrib/hosted/fwcf/sys_bsd.c,v 1.4 2007/03/13 18:14:30 tg Exp $");
  31
  32 void
  33 pull_rndata(uint8_t *buf, size_t n)
  34 {
  35 #ifdef RND_DISABLE
  36         while (n--)
  37                 *buf++ = 0xF6;
  38         *--buf = 0xFF;
  39 #else
  40 #ifdef RND_DEBUG
  41         fprintf(stderr, "writing %ld bytes of entropy\n", n);
  42         while (n > 4) {
  43 #else
  44         while (n >= 4) {
  45 #endif
  46                 *(uint32_t *)buf = arc4random();
  47 #ifdef RND_DEBUG
  48                 *buf = 0xF6;
  49 #endif
  50                 buf += 4;
  51                 n -= 4;
  52         }
  53         while (n) {
  54 #ifdef RND_DEBUG
  55                 *buf++ = 0xF6;
  56 #else
  57                 *buf++ = arc4random() & 0xFF;
  58 #endif
  59                 n--;
  60         }
  61 #ifdef RND_DEBUG
  62                 *--buf = 0xFF;
  63 #endif
  64 #endif
  65 }
  66
  67 void
  68 push_rndata(uint8_t *buf, size_t n)
  69 {
  70 #ifdef RND_DEBUG
  71         size_t i;
  72 #endif
  73 #ifdef __MirBSD__
  74         arc4random_pushb(buf, n);
  75 #else
  76         int fd;
  77         uint32_t x;
  78
  79         arc4random_addrandom(buf, n);
  80         x = arc4random();
  81         if ((fd = open("/dev/arandom", O_WRONLY)) >= 0) {
  82                 write(fd, &x, 4);
  83                 close(fd);
  84         } else
  85                 warn("cannot write to /dev/arandom");
  86 #endif
  87 #ifdef RND_DEBUG
  88         printf("reading %ld bytes of entropy\n", n);
  89         for (i = 0; i < n; ++i) {
  90                 printf(" %02X", buf[i]);
  91                 if ((i & 0xF) == 0xF)
  92                         putchar('\n');
  93         }
  94         putchar('\n');
  95 #endif
  96 }