Nikos Mavrogiannopoulos nmav@redhat.com writes:
On Tue, 2017-05-16 at 22:47 +0200, Niels Möller wrote:
- while(left > 0) {
/* T(i) */set_key(mac_ctx, prk_size, prk);if (started != 0) {update(mac_ctx, digest_size, Ttmp);} else {started = 1;}if (info_size)update(mac_ctx, info_size, info);update(mac_ctx, 1, &i);if (left < digest_size)digest_size = left;digest(mac_ctx, digest_size, dst);Ttmp = dst;left -= digest_size;dst += digest_size;i++;- }
I think this loop would clearer if Ttmp was replaced by (dst - digest_size), and maybe it would make sense to take out the first and/or final iterations.
Patch 0005 unrolls the first loop and does that change. I find that longer and not as easy to follow, but I may have not caught what you meant.
I was thinking of something like
if (!length) return;
for (;; dst += digest_size, length -= digest_size, i++) { update(mac_ctx, info_size, info); /* info_size == 0 should work fine */ update(mac_ctx, 1, &i); if (left <= digest_size) { digest(mac_ctx, left, dst); return; } digest(max_ctx, digest_size, dst); update(mac_ctx, digest_size, dst); }
Regards, /Niels