tests/rng-fork.c

   1 /*
   2  * Copyright (C) 2008, 2010 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 #include "../lib/random.h"
  38
  39 #if !defined(_WIN32)
  40 static void dump(const char* name, unsigned char* buf, int buf_size)
  41 {
  42 int i;
  43   printf("%s: ", name);
  44   for(i=0;i<buf_size;i++)
  45     printf("%.2x:", buf[i]);
  46   printf("\n");
  47 }
  48
  49 #define FILENAME "./rng-test"
  50
  51 void
  52 doit (void)
  53 {
  54   unsigned char buf1[32];
  55   unsigned char buf2[32];
  56   pid_t pid;
  57   int ret;
  58   FILE* fp;
  59
  60   gnutls_global_init ();
  61   pid = fork();
  62   if (pid == 0)
  63     {
  64       fp = fopen(FILENAME, "w");
  65       if (fp == NULL)
  66         fail("cannot open file");
  67
  68       _gnutls_rnd (GNUTLS_RND_RANDOM, buf1, sizeof (buf1));
  69       if (debug) dump("buf1", buf1, sizeof(buf1));
  70
  71       fwrite(buf1, 1, sizeof(buf1), fp);
  72       fclose(fp);
  73     }
  74   else
  75     {
  76       /* daddy */
  77       _gnutls_rnd (GNUTLS_RND_RANDOM, buf2, sizeof (buf2));
  78       if (debug) dump("buf2", buf2, sizeof(buf2));
  79       waitpid(pid, NULL, 0);
  80
  81       fp = fopen(FILENAME, "r");
  82       if (fp == NULL)
  83         fail("cannot open file");
  84
  85       ret = fread(buf1, 1, sizeof(buf1), fp);
  86
  87       fclose(fp);
  88       remove(FILENAME);
  89
  90       if (ret != sizeof(buf1))
  91         {
  92           fail("error testing the random generator.");
  93           return;
  94         }
  95
  96       if (memcmp(buf1, buf2, sizeof(buf1))==0)
  97         {
  98           fail("error in the random generator. Produces same valus after fork()");
  99           return;
 100         }
 101
 102       success("success");
 103     }
 104 }
 105 #else
 106 void
 107 doit (void)
 108 {
 109   exit (77);
 110 }
 111 #endif