From 13f41e1c20a4a2ed81af332a4be32bd8265fc073 Mon Sep 17 00:00:00 2001
From: Andres Amaya Garcia <andres.amayagarcia@arm.com>
Date: Mon, 26 Jun 2017 10:56:58 +0100
Subject: [PATCH] Zeroize tmp bufs in ctr_drbg.c functions
---
library/ctr_drbg.c | 28 +++++++++++++---------------
1 file changed, 13 insertions(+), 15 deletions(-)
diff --git a/library/ctr_drbg.c b/library/ctr_drbg.c
index 55612c7fc..7828c4e37 100644
--- a/library/ctr_drbg.c
+++ b/library/ctr_drbg.c
@@ -430,12 +430,11 @@ int mbedtls_ctr_drbg_write_seed_file( mbedtls_ctr_drbg_context *ctx, const char
goto exit;
if( fwrite( buf, 1, MBEDTLS_CTR_DRBG_MAX_INPUT, f ) != MBEDTLS_CTR_DRBG_MAX_INPUT )
- {
ret = MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR;
- goto exit;
- }
+ else
+ ret = 0;
- ret = 0;
+ mbedtls_zeroize( buf, sizeof( buf ) );
exit:
fclose( f );
@@ -444,6 +443,7 @@ exit:
int mbedtls_ctr_drbg_update_seed_file( mbedtls_ctr_drbg_context *ctx, const char *path )
{
+ int ret = 0;
FILE *f;
size_t n;
unsigned char buf[ MBEDTLS_CTR_DRBG_MAX_INPUT ];
@@ -456,20 +456,18 @@ int mbedtls_ctr_drbg_update_seed_file( mbedtls_ctr_drbg_context *ctx, const char
fseek( f, 0, SEEK_SET );
if( n > MBEDTLS_CTR_DRBG_MAX_INPUT )
- {
- fclose( f );
- return( MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
- }
-
- if( fread( buf, 1, n, f ) != n )
- {
- fclose( f );
- return( MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR );
- }
+ ret = MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG;
+ else if( fread( buf, 1, n, f ) != n )
+ ret = MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR;
+ else
+ mbedtls_ctr_drbg_update( ctx, buf, n );
fclose( f );
- mbedtls_ctr_drbg_update( ctx, buf, n );
+ mbedtls_zeroize( buf, sizeof( buf ) );
+
+ if( ret != 0 )
+ return( ret );
return( mbedtls_ctr_drbg_write_seed_file( ctx, path ) );
}