Stop advertising an IPv6 exit policy when DNS is broken for IPv6
When dns_seems_to_be_broken_for_ipv6()
, exits should stop advertising an IPv6 exit policy.
Here's a rough design:
- when
dns_seems_to_be_broken_for_ipv6()
is first set to 1, mark the relay descriptor dirty - when rebuilding the descriptor, check
dns_seems_to_be_broken_for_ipv6()
before including an IPv6 exit policy - reset
dns_seems_to_be_broken_for_ipv6()
periodically, maybe every 1-3 days?