Re: [PATCH V6 5/7] crypto: AES CBC multi-buffer glue code
From: Herbert Xu
Date: Tue Jul 18 2017 - 01:42:25 EST
On Tue, Jun 27, 2017 at 05:26:13PM -0700, Megha Dey wrote:
>
> +static void completion_callback(struct mcryptd_skcipher_request_ctx *rctx,
> + struct mcryptd_alg_cstate *cstate,
> + int err)
> +{
> + struct skcipher_request *req = cast_mcryptd_ctx_to_req(rctx);
> +
> + /* remove from work list and invoke completion callback */
> + spin_lock(&cstate->work_lock);
> + list_del(&rctx->waiter);
> + spin_unlock(&cstate->work_lock);
> +
> + if (irqs_disabled())
> + rctx->complete(&req->base, err);
> + else {
> + local_bh_disable();
> + rctx->complete(&req->base, err);
> + local_bh_enable();
> + }
> +}
The fact that you need to do this check means that this design is
wrong. You should always know what context you are in.
> +/*
> + * CRYPTO_ALG_ASYNC flag is passed to indicate we have an ablk
> + * scatter-gather walk.
> + */
> +static struct skcipher_alg aes_cbc_mb_alg = {
> + .base = {
> + .cra_name = "cbc(aes)",
> + .cra_driver_name = "cbc-aes-aesni-mb",
> + .cra_priority = 500,
> + .cra_flags = CRYPTO_ALG_INTERNAL,
> + .cra_blocksize = AES_BLOCK_SIZE,
> + .cra_ctxsize = CRYPTO_AES_CTX_SIZE,
> + .cra_module = THIS_MODULE,
> + },
> + .min_keysize = AES_MIN_KEY_SIZE,
> + .max_keysize = AES_MAX_KEY_SIZE,
> + .ivsize = AES_BLOCK_SIZE,
> + .setkey = aes_set_key,
> + .encrypt = mb_aes_cbc_encrypt,
> + .decrypt = mb_aes_cbc_decrypt
> +};
So this claims to be a sync algorithm. Is this really the case?
Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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