On Tue, 30 Jul 2019 at 13:33, Iuliana Prodan <iuliana.prodan@xxxxxxx> wrote:
>
> Add inline helper function to check key length for AES algorithms.
> The key can be 128, 192 or 256 bits size.
> This function is used in the generic aes implementation.
>
> Signed-off-by: Iuliana Prodan <iuliana.prodan@xxxxxxx>
> ---
> include/crypto/aes.h | 17 +++++++++++++++++
> lib/crypto/aes.c | 8 ++++----
> 2 files changed, 21 insertions(+), 4 deletions(-)
>
> diff --git a/include/crypto/aes.h b/include/crypto/aes.h
> index 8e0f4cf..8ee07a8 100644
> --- a/include/crypto/aes.h
> +++ b/include/crypto/aes.h
> @@ -31,6 +31,23 @@ struct crypto_aes_ctx {
> extern const u32 crypto_ft_tab[4][256] ____cacheline_aligned;
> extern const u32 crypto_it_tab[4][256] ____cacheline_aligned;
>
> +/*
> + * validate key length for AES algorithms
> + */
> +static inline int crypto_aes_check_keylen(unsigned int keylen)
Please rename this to aes_check_keylen()
> +{
> + switch (keylen) {
> + case AES_KEYSIZE_128:
> + case AES_KEYSIZE_192:
> + case AES_KEYSIZE_256:
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
> unsigned int key_len);
>
> diff --git a/lib/crypto/aes.c b/lib/crypto/aes.c
> index 4e100af..3407b01 100644
> --- a/lib/crypto/aes.c
> +++ b/lib/crypto/aes.c
> @@ -187,11 +187,11 @@ int aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
> {
> u32 kwords = key_len / sizeof(u32);
> u32 rc, i, j;
> + int err;
>
> - if (key_len != AES_KEYSIZE_128 &&
> - key_len != AES_KEYSIZE_192 &&
> - key_len != AES_KEYSIZE_256)
> - return -EINVAL;
> + err = crypto_aes_check_keylen(key_len);
> + if (err)
> + return err;
>
> ctx->key_length = key_len;
>
> --
> 2.1.0
>
