- Added a generic entropy accumulator that provides support for adding custom entropy sources and added some generic and platform dependent entropy sources

2011-12-03 21:45:14 +00:00 · 2011-12-03 21:45:14 +00:00 · 6083fd252d
commit 6083fd252d
parent 1bc9efc00a
17 changed files with 771 additions and 20 deletions
--- a/library/entropy_poll.c
+++ b/library/entropy_poll.c
@ -0,0 +1,135 @@
+/*
+ *  Platform-specific and custom entropy polling functions
+ *
+ *  Copyright (C) 2006-2011, Brainspark B.V.
+ *
+ *  This file is part of PolarSSL (http://www.polarssl.org)
+ *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
+ *  All rights reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "polarssl/config.h"
+
+#if defined(POLARSSL_ENTROPY_C)
+
+#include "polarssl/entropy.h"
+#include "polarssl/entropy_poll.h"
+
+#if defined(POLARSSL_TIMING_C)
+#include "polarssl/timing.h"
+#endif
+#if defined(POLARSSL_HAVEGE_C)
+#include "polarssl/havege.h"
+#endif
+
+#if !defined(POLARSSL_NO_PLATFORM_ENTROPY)
+#if defined(_WIN32)
+
+#include <windows.h>
+#if !defined(_WIN32_WINNT)
+#define _WIN32_WINNT 0x0400
+#endif
+#include <wincrypt.h>
+
+int platform_entropy_poll( void *data, unsigned char *output, size_t len,
+                           size_t *olen )
+{
+    HCRYPTPROV provider;
+    *olen = 0;
+
+    if( CryptAcquireContext( &provider, NULL, NULL,
+                              PROV_RSA_FULL, CRYPT_VERIFYCONTEXT ) == FALSE )
+    {
+        return POLARSSL_ERR_ENTROPY_SOURCE_FAILED;
+    }
+
+    if( CryptGenRandom( provider, len, output ) == FALSE )
+        return POLARSSL_ERR_ENTROPY_SOURCE_FAILED;
+
+    CryptReleaseContext( provider, 0 );
+    *olen = len;
+
+    return( 0 );
+}
+#else
+
+#include <stdio.h>
+
+int platform_entropy_poll( void *data,
+                           unsigned char *output, size_t len, size_t *olen )
+{
+    FILE *file;
+    size_t ret;
+    ((void) data);
+
+    *olen = 0;
+
+    file = fopen( "/dev/urandom", "rb" );
+    if( file == NULL )
+        return POLARSSL_ERR_ENTROPY_SOURCE_FAILED;
+    
+    ret = fread( output, 1, len, file );
+    if( ret != len )
+    {
+        fclose( file );
+        return POLARSSL_ERR_ENTROPY_SOURCE_FAILED;
+    }
+
+    fclose( file );
+    *olen = len;
+
+    return( 0 );
+}
+#endif
+#endif
+
+#if defined(POLARSSL_TIMING_C)
+int hardclock_poll( void *data,
+                    unsigned char *output, size_t len, size_t *olen )
+{
+    unsigned long timer = hardclock();
+    ((void) data);
+    *olen = 0;
+
+    if( len < sizeof(unsigned long) )
+        return( 0 );
+
+    memcpy( output, &timer, sizeof(unsigned long) );
+    *olen = sizeof(unsigned long);
+
+    return( 0 );
+}
+#endif
+
+#if defined(POLARSSL_HAVEGE_C)
+int havege_poll( void *data,
+                 unsigned char *output, size_t len, size_t *olen )
+{
+    havege_state *hs = (havege_state *) data;
+    *olen = 0;
+
+    if( havege_random( hs, output, len ) != 0 )
+        return POLARSSL_ERR_ENTROPY_SOURCE_FAILED;
+
+    *olen = len;
+
+    return( 0 );
+}
+#endif
+
+#endif /* POLARSSL_ENTROPY_C */