Re: [RESEND PATCH 06/10] crypto: sa2ul: Add hmac(sha256)cbc(aes) AEAD Algo support

From: Eric Biggers
Date: Fri Jun 28 2019 - 01:12:18 EST


On Fri, Jun 28, 2019 at 09:57:41AM +0530, Keerthy wrote:
> Add aead support for hmac(sha256)cbc(aes) algorithm. Authenticated
> encryption (AE) and authenticated encryption with associated data
> (AEAD) is a form of encryption which simultaneously provides
> confidentiality, integrity, and authenticity assurances on the data.
>
> hmac(sha256) has a digest size of 32 bytes is used for authetication
> and AES in CBC mode is used in conjunction for encryption/decryption.
>
> Signed-off-by: Keerthy <j-keerthy@xxxxxx>
> ---
> drivers/crypto/sa2ul.c | 92 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 92 insertions(+)
>
> diff --git a/drivers/crypto/sa2ul.c b/drivers/crypto/sa2ul.c
> index 1a1bd882e0d2..9c9008e21867 100644
> --- a/drivers/crypto/sa2ul.c
> +++ b/drivers/crypto/sa2ul.c
> @@ -271,6 +271,42 @@ void sa_hmac_sha1_get_pad(const u8 *key, u16 key_sz, u32 *ipad, u32 *opad)
> opad[i] = cpu_to_be32(opad[i]);
> }
>
> +void sha256_init(u32 *buf)

This needs to be static.

> +static int sa_aead_cbc_sha256_setkey(struct crypto_aead *authenc,
> + const u8 *key, unsigned int keylen)
> +{
> + struct algo_data *ad = kzalloc(sizeof(*ad), GFP_KERNEL);
> + struct crypto_authenc_keys keys;
> + int ret = 0, key_idx;
> +
> + ret = crypto_authenc_extractkeys(&keys, key, keylen);
> + if (ret)
> + return ret;
> +
> + /* Convert the key size (16/24/32) to the key size index (0/1/2) */
> + key_idx = (keys.enckeylen >> 3) - 2;

Where do you validate the key length?

- Eric