Add config macro for min bytes hw entropy
diff --git a/ChangeLog b/ChangeLog
index 2725f38..60383a9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,9 @@
calling mbedtls_x509_crt_parse_path().
* Added a configuration file config-no-entropy.h that enables a subset of
library features that do not require an entropy source.
+ * Added the macro MBEDTLS_ENTROPY_MIN_HARDWARE in config.h. This allows users
+ to configure the minimum number of bytes for entropy sources using the
+ mbedtls_hardware_poll() function.
Bugfix
* Fix for platform time abstraction to avoid dependency issues where a build
diff --git a/configs/config-no-entropy.h b/configs/config-no-entropy.h
index 91e4a02..95f17d4 100644
--- a/configs/config-no-entropy.h
+++ b/configs/config-no-entropy.h
@@ -22,7 +22,8 @@
* Minimal configuration of features that do not require an entropy source
* Distinguishing reatures:
* - no entropy module
- * - no TLS protocol implementation available due missing entropy source
+ * - no TLS protocol implementation available due to absence of an entropy
+ * source
*
* See README.txt for usage instructions.
*/
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 8a892d7..a58519b 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -2509,6 +2509,7 @@
/* Entropy options */
//#define MBEDTLS_ENTROPY_MAX_SOURCES 20 /**< Maximum number of sources supported */
//#define MBEDTLS_ENTROPY_MAX_GATHER 128 /**< Maximum amount requested from entropy sources */
+//#define MBEDTLS_ENTROPY_MIN_HARDWARE 32 /**< Default minimum number of bytes required for the hardware entropy source mbedtls_hardware_poll() before entropy is released */
/* Memory buffer allocator options */
//#define MBEDTLS_MEMORY_ALIGN_MULTIPLE 4 /**< Align on multiples of this value */
diff --git a/include/mbedtls/entropy_poll.h b/include/mbedtls/entropy_poll.h
index 430e865..81258d5 100644
--- a/include/mbedtls/entropy_poll.h
+++ b/include/mbedtls/entropy_poll.h
@@ -41,7 +41,9 @@
#define MBEDTLS_ENTROPY_MIN_PLATFORM 32 /**< Minimum for platform source */
#define MBEDTLS_ENTROPY_MIN_HAVEGE 32 /**< Minimum for HAVEGE */
#define MBEDTLS_ENTROPY_MIN_HARDCLOCK 4 /**< Minimum for mbedtls_timing_hardclock() */
+#if !defined(MBEDTLS_ENTROPY_MIN_HARDWARE)
#define MBEDTLS_ENTROPY_MIN_HARDWARE 32 /**< Minimum for the hardware source */
+#endif
/**
* \brief Entropy poll callback that provides 0 entropy.
