const MAX_ALLOWED_UNVERIFIABLE_PIX_SHARES: usize = 0;Expand description
Number of PIX verification failures tolerated before the session is closed.
Zero: the first failure closes the session.
A failure now means a whole polynomial’s share set did not open its commitment (or a single
share that was not a valid field element), not an individual share caught by a per-share
Feldman check — those were dropped along with the non-constant coefficient commitments, see
hopr_protocol_pix::SsaPartCommitment. That changes what tolerating failures would buy:
- A failed polynomial already dooms the whole cycle, because the SSA is the sum of every polynomial’s constant term. There is no partial recovery to preserve.
- A share that fails to reconstruct implies a dishonest or broken Entry — the share arrives inside a Sphinx-authenticated SURB and is decrypted with the key its own acknowledgement challenge fixes, so there is no benign path to a corrupt one.
Detection is also later than it used to be: the failure surfaces on the threshold-th share of
the polynomial, so the Exit has already served that many packets. Closing on the first failure
is what keeps that exposure at threshold packets instead of a multiple of it.