iPXE
entropy_sample.c
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1 /*
2  * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of the
7  * License, or any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  *
19  * You can also choose to distribute this program under the terms of
20  * the Unmodified Binary Distribution Licence (as given in the file
21  * COPYING.UBDL), provided that you have satisfied its requirements.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 /** @file
27  *
28  * Entropy sampling
29  *
30  */
31 
32 #include <stdio.h>
33 #include <ipxe/entropy.h>
34 #include <ipxe/test.h>
35 
36 /** Total number of test samples */
37 #define SAMPLE_COUNT 65536
38 
39 /** Number of samples per block */
40 #define SAMPLE_BLOCKSIZE 256
41 
42 /**
43  * Generate entropy samples for external testing
44  *
45  */
46 static void entropy_sample_test_exec ( void ) {
47  static noise_sample_t samples[SAMPLE_BLOCKSIZE];
48  unsigned int i;
49  unsigned int j;
50  int rc;
51 
52  /* Collect and print blocks of samples */
53  for ( i = 0 ; i < ( SAMPLE_COUNT / SAMPLE_BLOCKSIZE ) ; i++ ) {
54 
55  /* Collect one block of samples */
56  rc = entropy_enable();
57  ok ( rc == 0 );
58  for ( j = 0 ; j < SAMPLE_BLOCKSIZE ; j++ ) {
59  rc = get_noise ( &samples[j] );
60  ok ( rc == 0 );
61  }
63 
64  /* Print out sample values */
65  for ( j = 0 ; j < SAMPLE_BLOCKSIZE ; j++ ) {
66  printf ( "SAMPLE %d %d\n", ( i * SAMPLE_BLOCKSIZE + j ),
67  samples[j] );
68  }
69  }
70 }
71 
72 /** Entropy sampling self-test */
73 struct self_test entropy_sample_test __self_test = {
74  .name = "entropy_sample",
76 };
struct arbelprm_rc_send_wqe rc
Definition: arbel.h:14
void entropy_disable(void)
Disable entropy gathering.
int printf(const char *fmt,...)
Write a formatted string to the console.
Definition: vsprintf.c:464
int get_noise(noise_sample_t *noise)
Get noise sample.
Self-test infrastructure.
const char * name
Test set name.
Definition: test.h:17
A self-test set.
Definition: test.h:15
struct self_test entropy_sample_test __self_test
Entropy sampling self-test.
#define SAMPLE_COUNT
Total number of test samples.
int entropy_enable(void)
Enable entropy gathering.
#define SAMPLE_BLOCKSIZE
Number of samples per block.
uint8_t noise_sample_t
A noise sample.
Definition: entropy.h:50
static void entropy_sample_test_exec(void)
Generate entropy samples for external testing.
FILE_LICENCE(GPL2_OR_LATER_OR_UBDL)
#define ok(success)
Definition: test.h:46
Entropy source.