Recently, I started looking up for details about implementing a blind signature on ed25519 cryptographic. I saw this article https://stan.bar/blindsig/ by Stanislaw Baranski about it. In the first point, it says that Bob generates random number (nonce) $k$ in range $(1, q-1)$, computes $r=k \times G (\mod p)$ $r=k×G(\mod p)$ and sends $r$ to Alice.
Now, how safe it is to make $r$ public and to share the same r across different signer? or should I make differents $r$ for each signer and still publicly publish all $r$?
mod p
still applies for scalar-only arithmetic - I just meant it should not appear on a line which has point operations, since you don'tmod p
a point. One other thing - when dealing with point coordinates, the x and y are mod q, where q is the dimension of the finite field, i.e. 2^255-19. The other number, p, is the group order, and is a different number that scalar-only operations are modded by. Random scalars are less than p, so that part of your article is correct as long as you don't say earlier that p = 2^255-19 $\endgroup$