diff --git a/ChangeLog b/ChangeLog
index 06c8e3b..8817d9f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -11,6 +11,9 @@
    * Added cipher_get_cipher_mode() and cipher_get_cipher_operation()
      introspection functions (Closes ticket #40)
    * Added CTR_DRBG based on AES-256-CTR (NIST SP 800-90) random generator
+   * Added a generic entropy accumulator that provides support for adding
+     custom entropy sources and added some generic and platform dependent
+	 entropy sources
 
 Changes
    * Documentation for AES and Camellia in modes CTR and CFB128 clarified.
diff --git a/doxygen/input/doc_rng.h b/doxygen/input/doc_rng.h
index 252ee1e..40852ee 100644
--- a/doxygen/input/doc_rng.h
+++ b/doxygen/input/doc_rng.h
@@ -7,7 +7,14 @@
  * @addtogroup rng_module Random number generator (RNG) module
  * 
  * The Random number generator (RNG) module provides random number
- * generation, see \c havege_rand(). It uses the HAVEGE (HArdware Volatile 
+ * generation, see \c ctr_dbrg_random() or \c havege_random().
+ *
+ * The former uses the block-cipher counter-mode based deterministic random
+ * bit generator (CTR_DBRG) as specified in NIST SP800-90. It needs an external
+ * source of entropy. For these purposes \c entropy_func() can be used. This is
+ * an implementation based on a simple entropy accumulator design.
+ *
+ * The latter random number generator uses the HAVEGE (HArdware Volatile
  * Entropy Gathering and Expansion) software heuristic which is claimed 
  * to be an unpredictable or empirically strong* random number generation.
  *
diff --git a/include/polarssl/config.h b/include/polarssl/config.h
index 27f520b..1327c43 100644
--- a/include/polarssl/config.h
+++ b/include/polarssl/config.h
@@ -155,6 +155,17 @@
 #define POLARSSL_FS_IO
 
 /**
+ * \def POLARSSL_NO_PLATFORM_ENTROPY
+ *
+ * Do not use built-in platform entropy functions.
+ * This is useful if your platform does not support
+ * standards like the /dev/urandom or Windows CryptoAPI.
+ *
+ * Uncomment this macro to disable the built-in platform entropy functions.
+#define POLARSSL_NO_PLATFORM_ENTROPY
+ */
+
+/**
  * \def POLARSSL_PKCS1_V21
  *
  * Requires: POLARSSL_MD_C, POLARSSL_RSA_C
@@ -208,6 +219,7 @@
  * Module:  library/aes.c
  * Caller:  library/ssl_tls.c
  *          library/pem.c
+ *          library/ctr_drbg.c
  *
  * This module enables the following ciphersuites:
  *      SSL_RSA_AES_128_SHA
@@ -314,6 +326,8 @@
  * Module:  library/ctr_drbg.c
  * Caller:
  *
+ * Requires: POLARSSL_AES_C
+ *
  * This module provides the CTR_DRBG AES-256 random number generator.
  */
 #define POLARSSL_CTR_DRBG_C
@@ -363,6 +377,20 @@
 #define POLARSSL_DHM_C
 
 /**
+ * \def POLARSSL_ENTROPY_C
+ *
+ * Enable the platform-specific entropy code.
+ *
+ * Module:  library/entropy.c
+ * Caller:
+ *
+ * Requires: POLARSSL_SHA4_C
+ *
+ * This module provides a generic entropy pool
+ */
+#define POLARSSL_ENTROPY_C
+
+/**
  * \def POLARSSL_ERROR_C
  *
  * Enable error code to error string conversion.
diff --git a/include/polarssl/entropy.h b/include/polarssl/entropy.h
new file mode 100644
index 0000000..46df929
--- /dev/null
+++ b/include/polarssl/entropy.h
@@ -0,0 +1,129 @@
+/**
+ * \file entropy.h
+ *
+ * \brief Entropy accumulator implementation
+ *
+ *  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.
+ */
+#ifndef POLARSSL_ENTROPY_H
+#define POLARSSL_ENTROPY_H
+
+#include <string.h>
+
+#include "sha4.h"
+
+#define POLARSSL_ERR_ENTROPY_SOURCE_FAILED                 -0x003A  /**< Critical entropy source failure. */
+#define POLARSSL_ERR_ENTROPY_MAX_SOURCES                   -0x003C  /**< No more sources can be added. */
+
+#define ENTROPY_MIN_POOL        128     /**< Minimum amount of pool entropy needed for release */
+#define ENTROPY_MAX_SOURCES     20      /**< Maximum number of sources supported */
+#define ENTROPY_MAX_GATHER      128     /**< Maximum amount requested from entropy sources */
+#define ENTROPY_BLOCK_SIZE      64      /**< Block size of entropy accumulator (SHA-512) */
+
+#define ENTROPY_SOURCE_MANUAL   ENTROPY_MAX_SOURCES
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief           Entropy poll callback pointer
+ *
+ * \param data      Callback-specific data pointer
+ * \param output    Data to fill
+ * \param len       Maximum size to provide
+ * \param olen      The actual amount of bytes put into the buffer (Can be 0)
+ *
+ * \return          0 if no critical failures occurred,
+ *                  POLARSSL_ERR_ENTROPY_SOURCE_FAILED otherwise
+ */
+typedef int (*f_source_ptr)(void *, unsigned char *, size_t, size_t *);
+
+/**
+ * \brief           Entropy context structure
+ */
+typedef struct 
+{
+    sha4_context    accumulator;
+    size_t          size;
+    int             source_count;
+    f_source_ptr    f_source[ENTROPY_MAX_SOURCES];
+    void *          p_source[ENTROPY_MAX_SOURCES];
+}
+entropy_context;
+
+/**
+ * \brief           Initialize the context
+ *
+ * \param ctx       Entropy context to initialize
+ */
+void entropy_init( entropy_context *ctx );
+
+/**
+ * \brief           Adds an entropy source to poll
+ *
+ * \param ctx       Entropy context
+ * \param f_source  Entropy function
+ * \param p_source  Function data
+ *
+ * \return          0 is successful or POLARSSL_ERR_ENTROPY_MAX_SOURCES
+ */
+int entropy_add_source( entropy_context *ctx,
+                        f_source_ptr f_source, void *p_source );
+
+/**
+ * \brief           Trigger an extra gather poll for the accumulator
+ *
+ * \param ctx       Entropy context
+ *
+ * \return          0 if successful, or POLARSSL_ERR_ENTROPY_SOURCE_FAILED
+ */
+int entropy_gather( entropy_context *ctx );
+
+/**
+ * \brief           Retrieve entropy from the accumulator (Max ENTROPY_BLOCK_SIZE)
+ *
+ * \param data      Entropy context
+ * \param output    Buffer to fill
+ * \param len       Length of buffer
+ *
+ * \return          0 if successful, or POLARSSL_ERR_ENTROPY_SOURCE_FAILED
+ */
+int entropy_func( void *data, unsigned char *output, size_t len );
+
+/**
+ * \brief           Add data to the accumulator manually
+ * 
+ * \param ctx       Entropy context
+ * \param data      Data to add
+ * \param len       Length of data
+ *
+ * \return          0 if successful
+ */
+int entropy_update_manual( entropy_context *ctx,
+                           const unsigned char *data, size_t len );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* entropy.h */
diff --git a/include/polarssl/entropy_poll.h b/include/polarssl/entropy_poll.h
new file mode 100644
index 0000000..d9acbe5
--- /dev/null
+++ b/include/polarssl/entropy_poll.h
@@ -0,0 +1,68 @@
+/**
+ * \file entropy_poll.h
+ *
+ * \brief 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.
+ */
+#ifndef POLARSSL_ENTROPY_POLL_H
+#define POLARSSL_ENTROPY_POLL_H
+
+#include <string.h>
+
+#include "config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if !defined(POLARSSL_NO_PLATFORM_ENTROPY)
+/**
+ * \brief           Platform-specific entropy poll callback
+ */
+int platform_entropy_poll( void *data,
+                           unsigned char *output, size_t len, size_t *olen );
+#endif
+
+#if defined(POLARSSL_HAVEGE_C)
+/**
+ * \brief           HAVEGE based entropy poll callback
+ *
+ * Requires an HAVEGE state as its data pointer.
+ */
+int havege_poll( void *data,
+                 unsigned char *output, size_t len, size_t *olen );
+#endif
+
+#if defined(POLARSSL_TIMING_C)
+/**
+ * \brief           hardclock-based entropy poll callback
+ */
+int hardclock_poll( void *data,
+                    unsigned char *output, size_t len, size_t *olen );
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* entropy_poll.h */
diff --git a/include/polarssl/error.h b/include/polarssl/error.h
index 7ef8a74..69e7b04 100644
--- a/include/polarssl/error.h
+++ b/include/polarssl/error.h
@@ -58,6 +58,7 @@
  * DES       1  0x0032-0x0032
  * NET      11  0x0040-0x0054
  * CTR_DBRG  3  0x0034-0x0038
+ * ENTROPY   2  0x003A-0x003C
  *
  * High-level module nr (3 bits - 0x1...-0x8...)
  * Name     ID  Nr of Errors
diff --git a/library/CMakeLists.txt b/library/CMakeLists.txt
index 13d9549..4cfaf33 100644
--- a/library/CMakeLists.txt
+++ b/library/CMakeLists.txt
@@ -14,6 +14,8 @@
      debug.c
      des.c
      dhm.c
+     entropy.c
+     entropy_poll.c
      error.c
      havege.c
      md.c
diff --git a/library/Makefile b/library/Makefile
index 002087d..26de4d7 100644
--- a/library/Makefile
+++ b/library/Makefile
@@ -22,18 +22,18 @@
 # Windows shared library extension:
 # DLEXT=dll
 
-OBJS=	aes.o		arc4.o		asn1parse.o	\
-		base64.o	bignum.o	camellia.o	\
+OBJS=	aes.o		arc4.o		asn1parse.o		\
+		base64.o	bignum.o	camellia.o		\
 		certs.o		cipher.o	cipher_wrap.o	\
-		ctr_drbg.o	debug.o	\
-		des.o		dhm.o		havege.o	\
-		error.o \
-		md.o		md_wrap.o	md2.o		\
-		md4.o		md5.o		net.o		\
-		padlock.o	pem.o		pkcs11.o	\
-		rsa.o		sha1.o		sha2.o		\
-		sha4.o		ssl_cli.o	ssl_srv.o	\
-		ssl_tls.o	timing.o	version.o	\
+		ctr_drbg.o	debug.o		des.o			\
+		dhm.o		entropy.o	entropy_poll.o	\
+		error.o		havege.o					\
+		md.o		md_wrap.o	md2.o			\
+		md4.o		md5.o		net.o			\
+		padlock.o	pem.o		pkcs11.o		\
+		rsa.o		sha1.o		sha2.o			\
+		sha4.o		ssl_cli.o	ssl_srv.o		\
+		ssl_tls.o	timing.o	version.o		\
 		x509parse.o	xtea.o
 	
 
diff --git a/library/entropy.c b/library/entropy.c
new file mode 100644
index 0000000..0ece345
--- /dev/null
+++ b/library/entropy.c
@@ -0,0 +1,173 @@
+/*
+ *  Entropy accumulator implementation
+ *
+ *  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"
+
+#define ENTROPY_MAX_LOOP    256     /**< Maximum amount to loop before error */
+
+void entropy_init( entropy_context *ctx )
+{
+    memset( ctx, 0, sizeof(entropy_context) );
+
+    sha4_starts( &ctx->accumulator, 0 );
+
+#if !defined(POLARSSL_NO_PLATFORM_ENTROPY)
+    entropy_add_source( ctx, platform_entropy_poll, NULL );
+#endif
+#if defined(POLARSSL_TIMING_C)
+    entropy_add_source( ctx, hardclock_poll, NULL );
+#endif
+}
+
+int entropy_add_source( entropy_context *ctx,
+                        f_source_ptr f_source, void *p_source )
+{
+    if( ctx->source_count >= ENTROPY_MAX_SOURCES )
+        return( POLARSSL_ERR_ENTROPY_MAX_SOURCES );
+
+    ctx->f_source[ctx->source_count] = f_source;
+    ctx->p_source[ctx->source_count] = p_source;
+
+    ctx->source_count++;
+
+    return( 0 );
+}
+
+/*
+ * Entropy accumulator update
+ */
+int entropy_update( entropy_context *ctx, unsigned char source_id,
+                    const unsigned char *data, size_t len )
+{
+    unsigned char header[2];
+    unsigned char tmp[ENTROPY_BLOCK_SIZE];
+    size_t use_len = len;
+    const unsigned char *p = data;
+   
+    if( use_len > ENTROPY_BLOCK_SIZE )
+    {
+        sha4( data, len, tmp, 0 );
+
+        p = tmp;
+        use_len = ENTROPY_BLOCK_SIZE;
+    }
+
+    header[0] = source_id;
+    header[1] = use_len & 0xFF;
+
+    sha4_update( &ctx->accumulator, header, 2 );
+    sha4_update( &ctx->accumulator, p, use_len );
+    
+    ctx->size += use_len;
+
+    return( 0 );
+}
+
+int entropy_update_manual( entropy_context *ctx,
+                           const unsigned char *data, size_t len )
+{
+    return entropy_update( ctx, ENTROPY_SOURCE_MANUAL, data, len );
+}
+
+/*
+ * Run through the different sources to add entropy to our accumulator
+ */
+int entropy_gather( entropy_context *ctx )
+{
+    int ret, i;
+    unsigned char buf[ENTROPY_MAX_GATHER];
+    size_t olen;
+    
+    /*
+     * Run through our entropy sources
+     */
+    for( i = 0; i < ctx->source_count; i++ )
+    {
+        olen = 0;
+        if ( ( ret = ctx->f_source[i]( ctx->p_source[i],
+                        buf, ENTROPY_MAX_GATHER, &olen ) ) != 0 )
+        {
+            return( ret );
+        }
+
+        /*
+         * Add if we actually gathered something
+         */
+        if( olen > 0 )
+            entropy_update( ctx, (unsigned char) i, buf, olen );
+    }
+
+    return( 0 );
+}
+
+int entropy_func( void *data, unsigned char *output, size_t len )
+{
+    int ret, count = 0;
+    entropy_context *ctx = (entropy_context *) data;
+    unsigned char buf[ENTROPY_BLOCK_SIZE];
+
+    if( len > ENTROPY_BLOCK_SIZE )
+        return( POLARSSL_ERR_ENTROPY_SOURCE_FAILED );
+
+    /*
+     * Always gather extra entropy before a call
+     */
+    do
+    {
+        if( count++ > ENTROPY_MAX_LOOP )
+            return( POLARSSL_ERR_ENTROPY_SOURCE_FAILED );
+
+        if( ( ret = entropy_gather( ctx ) ) != 0 )
+            return( ret );
+    }
+    while( ctx->size < ENTROPY_MIN_POOL );
+
+    memset( buf, 0, ENTROPY_BLOCK_SIZE );
+
+    sha4_finish( &ctx->accumulator, buf );
+                
+    /*
+     * Perform second SHA-512 on entropy
+     */
+    sha4( buf, ENTROPY_BLOCK_SIZE, buf, 0 );
+
+    /*
+     * Reset accumulator
+     */
+    memset( &ctx->accumulator, 0, sizeof( sha4_context ) );
+    sha4_starts( &ctx->accumulator, 0 );
+    ctx->size = 0;
+
+    memcpy( output, buf, len );
+
+    return( 0 );
+}
+
+#endif
diff --git a/library/entropy_poll.c b/library/entropy_poll.c
new file mode 100644
index 0000000..270eb86
--- /dev/null
+++ 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 */
diff --git a/library/error.c b/library/error.c
index afe8e45..d5ad617 100644
--- a/library/error.c
+++ b/library/error.c
@@ -59,6 +59,10 @@
 #include "polarssl/dhm.h"
 #endif
 
+#if defined(POLARSSL_ENTROPY_C)
+#include "polarssl/entropy.h"
+#endif
+
 #if defined(POLARSSL_MD_C)
 #include "polarssl/md.h"
 #endif
@@ -391,6 +395,13 @@
         snprintf( buf, buflen, "DES - The data input has an invalid length" );
 #endif /* POLARSSL_DES_C */
 
+#if defined(POLARSSL_ENTROPY_C)
+    if( use_ret == -(POLARSSL_ERR_ENTROPY_SOURCE_FAILED) )
+        snprintf( buf, buflen, "ENTROPY - Critical entropy source failure" );
+    if( use_ret == -(POLARSSL_ERR_ENTROPY_MAX_SOURCES) )
+        snprintf( buf, buflen, "ENTROPY - No more sources can be added" );
+#endif /* POLARSSL_ENTROPY_C */
+
 #if defined(POLARSSL_NET_C)
     if( use_ret == -(POLARSSL_ERR_NET_UNKNOWN_HOST) )
         snprintf( buf, buflen, "NET - Failed to get an IP address for the given hostname" );
diff --git a/programs/Makefile b/programs/Makefile
index ceb0622..c8b6def 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -19,7 +19,9 @@
 	pkey/rsa_sign_pss	pkey/rsa_verify_pss \
 	ssl/ssl_client1		ssl/ssl_client2		\
 	ssl/ssl_server		ssl/ssl_fork_server	\
-	ssl/ssl_mail_client	random/gen_random	\
+	ssl/ssl_mail_client	random/gen_entropy	\
+	random/gen_random_havege				\
+	random/gen_random_ctr_drbg				\
 	test/ssl_cert_test	test/benchmark		\
 	test/selftest		test/ssl_test		\
 	x509/cert_app		x509/crl_app
@@ -104,9 +106,17 @@
 	echo   "  CC    pkey/rsa_encrypt.c"
 	$(CC) $(CFLAGS) $(OFLAGS) pkey/rsa_encrypt.c    $(LDFLAGS) -o $@
 
-random/gen_random: random/gen_random.c ../library/libpolarssl.a
-	echo   "  CC    random/gen_random.c"
-	$(CC) $(CFLAGS) $(OFLAGS) random/gen_random.c $(LDFLAGS) -o $@
+random/gen_entropy: random/gen_entropy.c ../library/libpolarssl.a
+	echo   "  CC    random/gen_entropy.c"
+	$(CC) $(CFLAGS) $(OFLAGS) random/gen_entropy.c $(LDFLAGS) -o $@
+
+random/gen_random_havege: random/gen_random_havege.c ../library/libpolarssl.a
+	echo   "  CC    random/gen_random_havege.c"
+	$(CC) $(CFLAGS) $(OFLAGS) random/gen_random_havege.c $(LDFLAGS) -o $@
+
+random/gen_random_ctr_drbg: random/gen_random_ctr_drbg.c ../library/libpolarssl.a
+	echo   "  CC    random/gen_random_ctr_drbg.c"
+	$(CC) $(CFLAGS) $(OFLAGS) random/gen_random_ctr_drbg.c $(LDFLAGS) -o $@
 
 ssl/ssl_client1: ssl/ssl_client1.c ../library/libpolarssl.a
 	echo   "  CC    ssl/ssl_client1.c"
diff --git a/programs/random/CMakeLists.txt b/programs/random/CMakeLists.txt
index 3196e46..94814c4 100644
--- a/programs/random/CMakeLists.txt
+++ b/programs/random/CMakeLists.txt
@@ -1,6 +1,12 @@
-add_executable(gen_random gen_random.c)
-target_link_libraries(gen_random polarssl)
+add_executable(gen_random_havege gen_random.c)
+target_link_libraries(gen_random_havege polarssl)
 
-INSTALL(TARGETS gen_random
+add_executable(gen_random_ctr_drbg gen_random_ctr_drbg.c)
+target_link_libraries(gen_random_ctr_drbg polarssl)
+
+add_executable(gen_entropy gen_entropy.c)
+target_link_libraries(gen_entropy polarssl)
+
+INSTALL(TARGETS gen_random_havege gen_random_ctr_drbg gen_entropy
         DESTINATION "bin"
         PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
diff --git a/programs/random/gen_entropy.c b/programs/random/gen_entropy.c
new file mode 100644
index 0000000..38c104c
--- /dev/null
+++ b/programs/random/gen_entropy.c
@@ -0,0 +1,87 @@
+/**
+ *  \brief Use and generate multiple entropies calls into a file
+ *
+ *  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"
+
+#include "polarssl/entropy.h"
+
+#include <stdio.h>
+
+#if !defined(POLARSSL_ENTROPY_C)
+int main( int argc, char *argv[] )
+{
+    ((void) argc);
+    ((void) argv);
+
+    printf("POLARSSL_ENTROPY_C not defined.\n");
+    return( 0 );
+}
+#else
+int main( int argc, char *argv[] )
+{
+    FILE *f;
+    int i, k, ret;
+    entropy_context entropy;
+    unsigned char buf[ENTROPY_BLOCK_SIZE];
+
+    if( argc < 2 )
+    {
+        fprintf( stderr, "usage: %s <output filename>\n", argv[0] );
+        return( 1 );
+    }
+
+    if( ( f = fopen( argv[1], "wb+" ) ) == NULL )
+    {
+        printf( "failed to open '%s' for writing.\n", argv[0] );
+        return( 1 );
+    }
+
+    entropy_init( &entropy );
+
+    for( i = 0, k = 768; i < k; i++ )
+    {
+        ret = entropy_func( &entropy, buf, sizeof( buf ) );
+        if( ret != 0 )
+        {
+            printf("failed!\n");
+            goto cleanup;
+        }
+
+        fwrite( buf, 1, sizeof( buf ), f );
+
+        printf( "Generating 32Mb of data in file '%s'... %04.1f" \
+                "%% done\r", argv[1], (100 * (float) (i + 1)) / k );
+        fflush( stdout );
+    }
+
+    ret = 0;
+
+cleanup:
+
+    fclose( f );
+
+    return( ret );
+}
+#endif /* POLARSSL_ENTROPY_C */
diff --git a/programs/random/gen_random_ctr_drbg.c b/programs/random/gen_random_ctr_drbg.c
new file mode 100644
index 0000000..e926ad0
--- /dev/null
+++ b/programs/random/gen_random_ctr_drbg.c
@@ -0,0 +1,91 @@
+/**
+ *  \brief Use and generate random data into a file via the CTR_DBRG based on AES
+ *
+ *  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"
+
+#include "polarssl/entropy.h"
+#include "polarssl/ctr_drbg.h"
+
+#include <stdio.h>
+
+#if !defined(POLARSSL_CTR_DRBG_C) || !defined(POLARSSL_ENTROPY_C)
+int main( int argc, char *argv[] )
+{
+    ((void) argc);
+    ((void) argv);
+
+    printf("POLARSSL_CTR_DRBG_C or POLARSSL_ENTROPY_C not defined.\n");
+    return( 0 );
+}
+#else
+int main( int argc, char *argv[] )
+{
+    FILE *f;
+    int i, k, ret;
+    ctr_drbg_context ctr_drbg;
+    entropy_context entropy;
+    unsigned char buf[1024];
+
+    if( argc < 2 )
+    {
+        fprintf( stderr, "usage: %s <output filename>\n", argv[0] );
+        return( 1 );
+    }
+
+    if( ( f = fopen( argv[1], "wb+" ) ) == NULL )
+    {
+        printf( "failed to open '%s' for writing.\n", argv[0] );
+        return( 1 );
+    }
+
+    entropy_init( &entropy );
+    ctr_drbg_init( &ctr_drbg, entropy_func, &entropy, (unsigned char *) "RANDOM_GEN", 10 );
+    ctr_drbg_set_prediction_resistance( &ctr_drbg, CTR_DRBG_PR_OFF );
+
+    for( i = 0, k = 768; i < k; i++ )
+    {
+        ret = ctr_drbg_random( &ctr_drbg, buf, sizeof( buf ) );
+        if( ret != 0 )
+        {
+            printf("failed!\n");
+            goto cleanup;
+        }
+
+        fwrite( buf, 1, sizeof( buf ), f );
+
+        printf( "Generating 32Mb of data in file '%s'... %04.1f" \
+                "%% done\r", argv[1], (100 * (float) (i + 1)) / k );
+        fflush( stdout );
+    }
+
+    ret = 0;
+
+cleanup:
+
+    fclose( f );
+
+    return( ret );
+}
+#endif /* POLARSSL_HAVEGE_C && POLARSSL_ENTROPY_C */
diff --git a/programs/random/gen_random.c b/programs/random/gen_random_havege.c
similarity index 100%
rename from programs/random/gen_random.c
rename to programs/random/gen_random_havege.c
diff --git a/scripts/generate_errors.pl b/scripts/generate_errors.pl
index 6d8b563..e07200f 100755
--- a/scripts/generate_errors.pl
+++ b/scripts/generate_errors.pl
@@ -9,7 +9,7 @@
 my $error_format_file = $data_dir.'/error.fmt';
 
 my @low_level_modules = ( "AES", "ASN1", "CAMELLIA", "BIGNUM", "BASE64", "XTEA",
-                          "PADLOCK", "DES", "NET", "CTR_DRBG" );
+                          "PADLOCK", "DES", "NET", "CTR_DRBG", "ENTROPY" );
 my @high_level_modules = ( "PEM", "X509", "DHM", "RSA", "MD", "CIPHER", "SSL" );
 
 my $line_separator = $/;