Make the fallback behavior of mbedtls_test_rnd_buffer_rand optional
If a fallback is not explicitly configured in the
mbedtls_test_rnd_buf_info structure, fail after the buffer is
exhausted.
There is no intended behavior change in this commit: all existing uses
of mbedtls_test_rnd_buffer_rand() have been updated to set
mbedtls_test_rnd_std_rand as the fallback.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/src/random.c b/tests/src/random.c
index e01bd4d..7f3f401 100644
--- a/tests/src/random.c
+++ b/tests/src/random.c
@@ -35,6 +35,8 @@
#include <test/random.h>
#include <string.h>
+#include <mbedtls/entropy.h>
+
int mbedtls_test_rnd_std_rand( void *rng_state,
unsigned char *output,
size_t len )
@@ -91,8 +93,16 @@
}
if( len - use_len > 0 )
- return( mbedtls_test_rnd_std_rand( NULL, output + use_len,
- len - use_len ) );
+ {
+ if( info->fallback_f_rng != NULL )
+ {
+ return( info->fallback_f_rng( info->fallback_p_rng,
+ output + use_len,
+ len - use_len ) );
+ }
+ else
+ return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
+ }
return( 0 );
}