Hi Vitaly,
On Sun, 2021-08-22 at 03:10 +0300, Vitaly Chikunov wrote:
> After CRYPTO_secure_malloc_init OpenSSL will store private keys
^and passwords
> in
> secure heap. This facility is only available since OpenSSL_1_1_0-pre1.
>
> Signed-off-by: Vitaly Chikunov <vt@xxxxxxxxxxxx>
Initially we started out discussing ways of protecting passwords, which
this patch does. Thank you! I'm not sure, however, it is protecting
the private keys. Does read_priv_pkey() also use the secure heap or
is PEM_read_PrivateKey() already safe?
> ---
> src/evmctl.c | 148 +++++++++++++++++++++++++++++++++++++++++----------
> 1 file changed, 121 insertions(+), 27 deletions(-)
>
> diff --git a/src/evmctl.c b/src/evmctl.c
>
> @@ -188,7 +207,9 @@ static int bin2file(const char *file, const char *ext, const unsigned char *data
> return err;
> }
>
> -static unsigned char *file2bin(const char *file, const char *ext, int *size)
> +/* Return data in OpenSSL secure heap if 'secure' is true. */
> +static unsigned char *file2bin(const char *file, const char *ext, int *size,
> + int secure)
> {
The only caller of file2bin() that sets "secure" is evm_calc_hmac(),
but evm_calc_hmac() is a debugging tool, not meant for setting the real
security.evm xattr.
The kernel EVM HMAC key is an "encrypted" key type, which should be
based on a "trusted" key. Neither of which are exposed to userspace
unencrypted.
Enabling DEBUG by default was suppose to be temporary. At this point,
should it be disabled? As evm_calc_hmac() is only meant for debugging,
do we really care whether evm_calc_hmac() uses a secure heap or stack
for private keys or passwords?
thanks,
Mimi
> FILE *fp;
> size_t len;
