Add extra zeroization to LMS and LMOTS
Signed-off-by: Raef Coles <raef.coles@arm.com>
diff --git a/library/lmots.c b/library/lmots.c
index a172f77..788063c 100644
--- a/library/lmots.c
+++ b/library/lmots.c
@@ -700,7 +700,7 @@
NULL, ( unsigned char * )y_hashed_digits );
if( ret )
{
- return( ret );
+ goto exit;
}
ret = public_key_from_hashed_digit_array( &priv_ctx->params,
@@ -708,7 +708,7 @@
ctx->public_key );
if( ret )
{
- return( ret );
+ goto exit;
}
memcpy( &ctx->params, &priv_ctx->params,
@@ -716,6 +716,9 @@
ctx->have_public_key = 1;
+exit:
+ mbedtls_platform_zeroize( y_hashed_digits, sizeof( y_hashed_digits ) );
+
return( ret );
}
@@ -765,14 +768,14 @@
tmp_digit_array );
if( ret )
{
- return( ret );
+ goto exit;
}
ret = hash_digit_array( &ctx->params, ( unsigned char * )ctx->private_key,
NULL, tmp_digit_array, ( unsigned char * )tmp_sig );
if( ret )
{
- return( ret );
+ goto exit;
}
mbedtls_lms_unsigned_int_to_network_bytes( ctx->params.type,
@@ -810,7 +813,13 @@
*sig_len = MBEDTLS_LMOTS_SIG_LEN(ctx->params.type);
}
- return( 0 );
+ ret = 0;
+
+exit:
+ mbedtls_platform_zeroize( tmp_digit_array, sizeof( tmp_digit_array ) );
+ mbedtls_platform_zeroize( tmp_sig, sizeof( tmp_sig ) );
+
+ return ( ret );
}
#endif /* defined(MBEDTLS_LMS_PRIVATE) */
diff --git a/library/lms.c b/library/lms.c
index f30f349..876deeb 100644
--- a/library/lms.c
+++ b/library/lms.c
@@ -516,7 +516,7 @@
ret = calculate_merkle_tree( ctx, ( unsigned char * )tree );
if( ret != 0 )
{
- return( ret );
+ goto exit;
}
for( height = 0; height < MBEDTLS_LMS_H_TREE_HEIGHT(ctx->params.type);
@@ -531,7 +531,12 @@
curr_node_id >>=1;
}
- return( 0 );
+ ret = 0;
+
+exit:
+ mbedtls_platform_zeroize( tree, sizeof( tree ) );
+
+ return( ret );
}
void mbedtls_lms_private_init( mbedtls_lms_private_t *ctx )
@@ -688,7 +693,7 @@
ret = calculate_merkle_tree( priv_ctx, ( unsigned char * )tree );
if( ret != 0 )
{
- return( ret );
+ goto exit;
}
/* Root node is always at position 1, due to 1-based indexing */
@@ -697,7 +702,12 @@
ctx->have_public_key = 1;
- return( 0 );
+ ret = 0;
+
+exit:
+ mbedtls_platform_zeroize( tree, sizeof( tree ) );
+
+ return( ret );
}