tests/rng-fork.c

   1 /*
   2  * Copyright (C) 2008-2012 Free Software Foundation, Inc.
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GnuTLS.
   7  *
   8  * GnuTLS is free software: you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation, either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * GnuTLS is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with GnuTLS.  If not, see <http://www.gnu.org/licenses/>.
  20  *
  21  */
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include <config.h>
  25 #endif
  26
  27 #include <stdio.h>
  28 #include <unistd.h>
  29 #include <sys/types.h>
  30 #if !defined(_WIN32)
  31 #include <sys/wait.h>
  32 #endif
  33
  34 #include "utils.h"
  35 #include <gnutls/gnutls.h>
  36 #include <gnutls/crypto.h>
  37
  38 #if !defined(_WIN32)
  39 static void dump(const char* name, unsigned char* buf, int buf_size)
  40 {
  41 int i;
  42   printf("%s: ", name);
  43   for(i=0;i<buf_size;i++)
  44     printf("%.2x:", buf[i]);
  45   printf("\n");
  46 }
  47
  48 #define FILENAME "./rng-test"
  49
  50 void
  51 doit (void)
  52 {
  53   unsigned char buf1[32];
  54   unsigned char buf2[32];
  55   pid_t pid;
  56   int ret;
  57   FILE* fp;
  58
  59   gnutls_global_init ();
  60   pid = fork();
  61   if (pid == 0)
  62     {
  63       fp = fopen(FILENAME, "w");
  64       if (fp == NULL)
  65         fail("cannot open file");
  66
  67       gnutls_rnd (GNUTLS_RND_RANDOM, buf1, sizeof (buf1));
  68       if (debug) dump("buf1", buf1, sizeof(buf1));
  69
  70       fwrite(buf1, 1, sizeof(buf1), fp);
  71       fclose(fp);
  72     }
  73   else
  74     {
  75       /* daddy */
  76       gnutls_rnd (GNUTLS_RND_RANDOM, buf2, sizeof (buf2));
  77       if (debug) dump("buf2", buf2, sizeof(buf2));
  78       waitpid(pid, NULL, 0);
  79
  80       fp = fopen(FILENAME, "r");
  81       if (fp == NULL)
  82         fail("cannot open file");
  83
  84       ret = fread(buf1, 1, sizeof(buf1), fp);
  85
  86       fclose(fp);
  87       remove(FILENAME);
  88
  89       if (ret != sizeof(buf1))
  90         {
  91           fail("error testing the random generator.");
  92           return;
  93         }
  94
  95       if (memcmp(buf1, buf2, sizeof(buf1))==0)
  96         {
  97           fail("error in the random generator. Produces same valus after fork()");
  98           return;
  99         }
 100       if(debug)
 101         success("success\n");
 102     }
 103
 104   gnutls_global_deinit ();
 105 }
 106 #else
 107 void
 108 doit (void)
 109 {
 110   exit (77);
 111 }
 112 #endif