Hi Herbert,
as discussed, these patches use the memzero_explicit function that is
yet to be integrated into the cryptodev-2.6 tree.
Stephan Mueller (2):
crypto: AF_ALG - zeroize message digest buffer
crypto: AF_ALG - zeroize IV buffer
crypto/algif_hash.c | 2 ++
crypto/algif_skcipher.c | 1 +
2 files changed, 3 insertions(+)
--
2.1.0
Zeroize the buffer holding the IV used for the completed
cipher operation before the buffer is released by the
skcipher AF_ALG interface handler.
Signed-off-by: Stephan Mueller <[email protected]>
---
crypto/algif_skcipher.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index 83187f4..85e3bdb 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -566,6 +566,7 @@ static void skcipher_sock_destruct(struct sock *sk)
struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(&ctx->req);
skcipher_free_sgl(sk);
+ memzero_explicit(ctx->iv, crypto_ablkcipher_ivsize(tfm));
sock_kfree_s(sk, ctx->iv, crypto_ablkcipher_ivsize(tfm));
sock_kfree_s(sk, ctx, ctx->len);
af_alg_release_parent(sk);
--
2.1.0
Zeroize the buffer holding the message digest calculated for the
consumer before the buffer is released by the hash AF_ALG interface
handler.
Signed-off-by: Stephan Mueller <[email protected]>
---
crypto/algif_hash.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index 8502462..f75db4c 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -258,6 +258,8 @@ static void hash_sock_destruct(struct sock *sk)
struct alg_sock *ask = alg_sk(sk);
struct hash_ctx *ctx = ask->private;
+ memzero_explicit(ctx->result,
+ crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
sock_kfree_s(sk, ctx->result,
crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
sock_kfree_s(sk, ctx, ctx->len);
--
2.1.0
Hi Stephan,
On 11/11/2014 05:37 AM, Stephan Mueller wrote:
> Zeroize the buffer holding the message digest calculated for the
> consumer before the buffer is released by the hash AF_ALG interface
> handler.
>
> Signed-off-by: Stephan Mueller <[email protected]>
> ---
> crypto/algif_hash.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
> index 8502462..f75db4c 100644
> --- a/crypto/algif_hash.c
> +++ b/crypto/algif_hash.c
> @@ -258,6 +258,8 @@ static void hash_sock_destruct(struct sock *sk)
> struct alg_sock *ask = alg_sk(sk);
> struct hash_ctx *ctx = ask->private;
>
> + memzero_explicit(ctx->result,
> + crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
> sock_kfree_s(sk, ctx->result,
Perhaps something like this (alternatively kzfree() would work, too) ...
static void __sock_kfree_s(struct sock *sk, void *mem, int size,
bool clear_mem)
{
if (WARN_ON_ONCE(!mem))
return;
if (clear_mem)
memzero_explicit(mem, size);
kfree(mem);
atomic_sub(size, &sk->sk_omem_alloc);
}
void sock_kfree_s(struct sock *sk, void *mem, int size)
{
__sock_kfree_s(sk, mem, size, false);
}
EXPORT_SYMBOL(sock_kfree_s);
void sock_kzfree_s(struct sock *sk, void *mem, int size)
{
__sock_kfree_s(sk, mem, size, true);
}
EXPORT_SYMBOL(sock_kzfree_s);
... so you could then just use it as drop-in in various places:
sock_kzfree_s(sk, ctx->result, ...);
> crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
> sock_kfree_s(sk, ctx, ctx->len);
>
Thanks,
Daniel
On Tue, Nov 11, 2014 at 05:36:16AM +0100, Stephan Mueller wrote:
> Hi Herbert,
>
> as discussed, these patches use the memzero_explicit function that is
> yet to be integrated into the cryptodev-2.6 tree.
>
> Stephan Mueller (2):
> crypto: AF_ALG - zeroize message digest buffer
> crypto: AF_ALG - zeroize IV buffer
>
> crypto/algif_hash.c | 2 ++
> crypto/algif_skcipher.c | 1 +
> 2 files changed, 3 insertions(+)
All applied.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt