On 11/1/21 16:34, Leonard Crestez wrote:
[..]
> +static int skb_shash_frags(struct shash_desc *desc,
> + struct sk_buff *skb)
> +{
> + struct sk_buff *frag_iter;
> + int err, i;
> +
> + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
> + skb_frag_t *f = &skb_shinfo(skb)->frags[i];
> + u32 p_off, p_len, copied;
> + struct page *p;
> + u8 *vaddr;
> +
> + skb_frag_foreach_page(f, skb_frag_off(f), skb_frag_size(f),
> + p, p_off, p_len, copied) {
> + vaddr = kmap_atomic(p);
> + err = crypto_shash_update(desc, vaddr + p_off, p_len);
> + kunmap_atomic(vaddr);
> + if (err)
> + return err;
> + }
> + }
> +
> + skb_walk_frags(skb, frag_iter) {
> + err = skb_shash_frags(desc, frag_iter);
> + if (err)
> + return err;
> + }
> +
> + return 0;
> +}
This seems quite sub-optimal: IIUC, shash should only be used for small
amount of hashing. That's why tcp-md5 uses ahash with scatterlists.
Which drives me to the question: why not reuse tcp_md5sig_pool code?
And it seems that you can avoid TCP_AUTHOPT_ALG_* enum and just supply
to crypto the string from socket option (like xfrm does).
Here is my idea:
https://lore.kernel.org/all/20211105014953.972946-6-dima@xxxxxxxxxx/T/#u
Thanks,
Dmitry
