- Added option to prevent default entropy sources from loading (POLARSSL_NO_DEFAULT_ENTROPY_SOURCES)
diff --git a/include/polarssl/config.h b/include/polarssl/config.h
index 1327c43..ea518d7 100644
--- a/include/polarssl/config.h
+++ b/include/polarssl/config.h
@@ -155,6 +155,19 @@
#define POLARSSL_FS_IO
/**
+ * \def POLARSSL_NO_DEFAULT_ENTROPY_SOURCES
+ *
+ * Do not add default entropy sources. These are the platform specific,
+ * hardclock and HAVEGE based poll functions.
+ *
+ * This is useful to have more control over the added entropy sources in an
+ * application.
+ *
+ * Uncomment this macro to prevent loading of default entropy functions.
+#define POLARSSL_NO_DEFAULT_ENTROPY_SOURCES
+ */
+
+/**
* \def POLARSSL_NO_PLATFORM_ENTROPY
*
* Do not use built-in platform entropy functions.
diff --git a/include/polarssl/entropy.h b/include/polarssl/entropy.h
index 6dea79a..53bce41 100644
--- a/include/polarssl/entropy.h
+++ b/include/polarssl/entropy.h
@@ -38,6 +38,7 @@
#define POLARSSL_ERR_ENTROPY_SOURCE_FAILED -0x003C /**< Critical entropy source failure. */
#define POLARSSL_ERR_ENTROPY_MAX_SOURCES -0x003E /**< No more sources can be added. */
+#define POLARSSL_ERR_ENTROPY_NO_SOURCES_DEFINED -0x0040 /**< No sources have been added to poll. */
#define ENTROPY_MAX_SOURCES 20 /**< Maximum number of sources supported */
#define ENTROPY_MAX_GATHER 128 /**< Maximum amount requested from entropy sources */
@@ -104,7 +105,7 @@
* \param threshold Minimum required from source before entropy is released
* ( with entropy_func() )
*
- * \return 0 is successful or POLARSSL_ERR_ENTROPY_MAX_SOURCES
+ * \return 0 if successful or POLARSSL_ERR_ENTROPY_MAX_SOURCES
*/
int entropy_add_source( entropy_context *ctx,
f_source_ptr f_source, void *p_source,
diff --git a/include/polarssl/error.h b/include/polarssl/error.h
index f167a7b..78ad362 100644
--- a/include/polarssl/error.h
+++ b/include/polarssl/error.h
@@ -58,7 +58,7 @@
* DES 1 0x0032-0x0032
* NET 11 0x0040-0x0054
* CTR_DBRG 3 0x0034-0x003A
- * ENTROPY 2 0x003C-0x003E
+ * ENTROPY 3 0x003C-0x0040
* MD2 1 0x0070-0x0070
* MD4 1 0x0072-0x0072
* MD5 1 0x0074-0x0074
diff --git a/library/entropy.c b/library/entropy.c
index ebace08..9662454 100644
--- a/library/entropy.c
+++ b/library/entropy.c
@@ -41,7 +41,11 @@
memset( ctx, 0, sizeof(entropy_context) );
sha4_starts( &ctx->accumulator, 0 );
+#if defined(POLARSSL_HAVEGE_C)
+ havege_init( &ctx->havege_data );
+#endif
+#if !defined(POLARSSL_NO_DEFAULT_ENTROPY_SOURCES)
#if !defined(POLARSSL_NO_PLATFORM_ENTROPY)
entropy_add_source( ctx, platform_entropy_poll, NULL,
ENTROPY_MIN_PLATFORM );
@@ -50,10 +54,10 @@
entropy_add_source( ctx, hardclock_poll, NULL, ENTROPY_MIN_HARDCLOCK );
#endif
#if defined(POLARSSL_HAVEGE_C)
- havege_init( &ctx->havege_data );
entropy_add_source( ctx, havege_poll, &ctx->havege_data,
ENTROPY_MIN_HAVEGE );
#endif
+#endif /* POLARSSL_NO_DEFAULT_ENTROPY_SOURCES */
}
int entropy_add_source( entropy_context *ctx,
@@ -117,6 +121,9 @@
unsigned char buf[ENTROPY_MAX_GATHER];
size_t olen;
+ if( ctx->source_count == 0 )
+ return( POLARSSL_ERR_ENTROPY_NO_SOURCES_DEFINED );
+
/*
* Run through our entropy sources
*/
diff --git a/library/error.c b/library/error.c
index 05e84e7..5dcd175 100644
--- a/library/error.c
+++ b/library/error.c
@@ -436,6 +436,8 @@
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" );
+ if( use_ret == -(POLARSSL_ERR_ENTROPY_NO_SOURCES_DEFINED) )
+ snprintf( buf, buflen, "ENTROPY - No sources have been added to poll" );
#endif /* POLARSSL_ENTROPY_C */
#if defined(POLARSSL_MD2_C)