Zeroize internal buffers and variables in PKCS and SHA
Zeroising of local buffers and variables which are used for calculations in
mbedtls_pkcs5_pbkdf2_hmac() and mbedtls_internal_sha*_process() functions
to erase sensitive data from memory.
Checked all function for possible missing zeroisation in PKCS and SHA.
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
diff --git a/library/sha256.c b/library/sha256.c
index d8ddda5..0124fb7 100644
--- a/library/sha256.c
+++ b/library/sha256.c
@@ -253,6 +253,12 @@
for( i = 0; i < 8; i++ )
ctx->state[i] += A[i];
+ /* Zeroise buffers and variables to clear sensitive data from memory. */
+ mbedtls_platform_zeroize( &A, sizeof( A ) );
+ mbedtls_platform_zeroize( &W, sizeof( W ) );
+ mbedtls_platform_zeroize( &temp1, sizeof( temp1 ) );
+ mbedtls_platform_zeroize( &temp2, sizeof( temp2 ) );
+
return( 0 );
}
