Re: [RFC v1 2/2] crypto/virtio-crypto: Register an algo only if it's supported

From: Farhan Ali
Date: Tue Jun 12 2018 - 13:07:56 EST




On 06/11/2018 04:48 AM, Gonglei (Arei) wrote:


-----Original Message-----
From: Farhan Ali [mailto:alifm@xxxxxxxxxxxxx]
Sent: Saturday, June 09, 2018 3:09 AM
To: linux-kernel@xxxxxxxxxxxxxxx; kvm@xxxxxxxxxxxxxxx
Cc: mst@xxxxxxxxxx; qemu-devel@xxxxxxxxxx; Gonglei (Arei)
<arei.gonglei@xxxxxxxxxx>; longpeng <longpeng2@xxxxxxxxxx>;
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alifm@xxxxxxxxxxxxx
Subject: [RFC v1 2/2] crypto/virtio-crypto: Register an algo only if it's supported

From: Farhan Ali <alifm@xxxxxxxxxxxxxxxxxx>

Register a crypto algo with the Linux crypto layer only if
the algorithm is supported by the backend virtio-crypto
device.

Also route crypto requests to a virtio-crypto
device, only if it can support the requested service and
algorithm.

Signed-off-by: Farhan Ali <alifm@xxxxxxxxxxxxx>
---
drivers/crypto/virtio/virtio_crypto_algs.c | 110
++++++++++++++++++---------
drivers/crypto/virtio/virtio_crypto_common.h | 11 ++-
drivers/crypto/virtio/virtio_crypto_mgr.c | 81 ++++++++++++++++++--
3 files changed, 158 insertions(+), 44 deletions(-)

diff --git a/drivers/crypto/virtio/virtio_crypto_algs.c
b/drivers/crypto/virtio/virtio_crypto_algs.c
index ba190cf..fef112a 100644
--- a/drivers/crypto/virtio/virtio_crypto_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_algs.c
@@ -49,12 +49,18 @@ struct virtio_crypto_sym_request {
bool encrypt;
};

+struct virtio_crypto_algo {
+ uint32_t algonum;
+ uint32_t service;
+ unsigned int active_devs;
+ struct crypto_alg algo;
+};
+
/*
* The algs_lock protects the below global virtio_crypto_active_devs
* and crypto algorithms registion.
*/
static DEFINE_MUTEX(algs_lock);
-static unsigned int virtio_crypto_active_devs;
static void virtio_crypto_ablkcipher_finalize_req(
struct virtio_crypto_sym_request *vc_sym_req,
struct ablkcipher_request *req,
@@ -312,13 +318,19 @@ static int virtio_crypto_ablkcipher_setkey(struct
crypto_ablkcipher *tfm,
unsigned int keylen)
{
struct virtio_crypto_ablkcipher_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+ uint32_t alg;
int ret;

+ ret = virtio_crypto_alg_validate_key(keylen, &alg);
+ if (ret)
+ return ret;
+
if (!ctx->vcrypto) {
/* New key */
int node = virtio_crypto_get_current_node();
struct virtio_crypto *vcrypto =
- virtcrypto_get_dev_node(node);
+ virtcrypto_get_dev_node(node,
+ VIRTIO_CRYPTO_SERVICE_CIPHER, alg);
if (!vcrypto) {
pr_err("virtio_crypto: Could not find a virtio device in the
system\n");

We'd better change the above error message now. What about:
" virtio_crypto: Could not find a virtio device in the system or unsupported algo" ?

Regards,
-Gonglei


Sure, I will update the error message. But other than that does the rest of the code looks good to you?

Thanks
Farhan