Line data    Source code

       1             : /*
       2             :  * Copyright (c) 2006 Kungliga Tekniska Högskolan
       3             :  * (Royal Institute of Technology, Stockholm, Sweden).
       4             :  * All rights reserved.
       5             :  *
       6             :  * Redistribution and use in source and binary forms, with or without
       7             :  * modification, are permitted provided that the following conditions
       8             :  * are met:
       9             :  *
      10             :  * 1. Redistributions of source code must retain the above copyright
      11             :  *    notice, this list of conditions and the following disclaimer.
      12             :  *
      13             :  * 2. Redistributions in binary form must reproduce the above copyright
      14             :  *    notice, this list of conditions and the following disclaimer in the
      15             :  *    documentation and/or other materials provided with the distribution.
      16             :  *
      17             :  * 3. Neither the name of the Institute nor the names of its contributors
      18             :  *    may be used to endorse or promote products derived from this software
      19             :  *    without specific prior written permission.
      20             :  *
      21             :  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
      22             :  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
      23             :  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
      24             :  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
      25             :  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
      26             :  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
      27             :  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
      28             :  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
      29             :  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
      30             :  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
      31             :  * SUCH DAMAGE.
      32             :  */
      33             : 
      34             : #include <config.h>
      35             : 
      36             : #include <stdio.h>
      37             : #include <stdlib.h>
      38             : #include <rand.h>
      39             : #include <heim_threads.h>
      40             : 
      41             : #include <roken.h>
      42             : 
      43             : #include "randi.h"
      44             : 
      45             : /*
      46             :  * Unix /dev/random
      47             :  */
      48             : 
      49             : int
      50       20545 : _hc_unix_device_fd(int flags, const char **fn)
      51             : {
      52             :     static const char *rnd_devices[] = {
      53             :         "/dev/urandom",
      54             :         "/dev/random",
      55             :         "/dev/srandom",
      56             :         "/dev/arandom",
      57             :         NULL
      58             :     };
      59             :     const char **p;
      60             : 
      61       20545 :     for(p = rnd_devices; *p; p++) {
      62       21138 :         int fd = open(*p, flags | O_NDELAY);
      63       20545 :         if(fd >= 0) {
      64       20545 :             if (fn)
      65           0 :                 *fn = *p;
      66       20545 :             rk_cloexec(fd);
      67       20545 :             return fd;
      68             :         }
      69             :     }
      70           0 :     return -1;
      71             : }
      72             : 
      73             : static void
      74           0 : unix_seed(const void *indata, int size)
      75             : {
      76             :     int fd;
      77             : 
      78           0 :     if (size <= 0)
      79           0 :         return;
      80             : 
      81           0 :     fd = _hc_unix_device_fd(O_WRONLY, NULL);
      82           0 :     if (fd < 0)
      83           0 :         return;
      84             : 
      85           0 :     write(fd, indata, size);
      86           0 :     close(fd);
      87             : 
      88             : }
      89             : 
      90             : 
      91             : static int
      92       20545 : unix_bytes(unsigned char *outdata, int size)
      93             : {
      94             :     ssize_t count;
      95             :     int fd;
      96             : 
      97       20545 :     if (size < 0)
      98           0 :         return 0;
      99       20545 :     else if (size == 0)
     100           0 :         return 1;
     101             : 
     102       20545 :     fd = _hc_unix_device_fd(O_RDONLY, NULL);
     103       20545 :     if (fd < 0)
     104           0 :         return 0;
     105             : 
     106       61042 :     while (size > 0) {
     107       21138 :         count = read(fd, outdata, size);
     108       20545 :         if (count < 0 && errno == EINTR)
     109           0 :             continue;
     110       20545 :         else if (count <= 0) {
     111           0 :             close(fd);
     112           0 :             return 0;
     113             :         }
     114       20545 :         outdata += count;
     115       20545 :         size -= count;
     116             :     }
     117       20545 :     close(fd);
     118             : 
     119       20545 :     return 1;
     120             : }
     121             : 
     122             : static void
     123           0 : unix_cleanup(void)
     124             : {
     125           0 : }
     126             : 
     127             : static void
     128           0 : unix_add(const void *indata, int size, double entropi)
     129             : {
     130           0 :     unix_seed(indata, size);
     131           0 : }
     132             : 
     133             : static int
     134           0 : unix_pseudorand(unsigned char *outdata, int size)
     135             : {
     136           0 :     return unix_bytes(outdata, size);
     137             : }
     138             : 
     139             : static int
     140           0 : unix_status(void)
     141             : {
     142             :     int fd;
     143             : 
     144           0 :     fd = _hc_unix_device_fd(O_RDONLY, NULL);
     145           0 :     if (fd < 0)
     146           0 :         return 0;
     147           0 :     close(fd);
     148             : 
     149           0 :     return 1;
     150             : }
     151             : 
     152             : const RAND_METHOD hc_rand_unix_method = {
     153             :     unix_seed,
     154             :     unix_bytes,
     155             :     unix_cleanup,
     156             :     unix_add,
     157             :     unix_pseudorand,
     158             :     unix_status
     159             : };
     160             : 
     161             : const RAND_METHOD *
     162           0 : RAND_unix_method(void)
     163             : {
     164           0 :     return &hc_rand_unix_method;
     165             : }