commit fbee4d25cc5672cd9b4fb79a8cb17c7464053ef8 Author: David Goulet dgoulet@torproject.org Date: Tue Jul 21 08:12:47 2020 -0400

relay: Don't publish IPv6 if found ORPort is 0

The ORPort can be IPv4Only which means that even if we can auto discover an IPv6 address, we should not publish it because it would have an ORPort of 0.

Fixes #40054

Signed-off-by: David Goulet dgoulet@torproject.org --- src/feature/relay/router.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/feature/relay/router.c b/src/feature/relay/router.c index b75241160f..c2b01a641d 100644 --- a/src/feature/relay/router.c +++ b/src/feature/relay/router.c @@ -2032,6 +2032,7 @@ router_build_fresh_unsigned_routerinfo,(routerinfo_t **ri_out)) int hibernating = we_are_hibernating(); const or_options_t *options = get_options(); int result = TOR_ROUTERINFO_ERROR_INTERNAL_BUG; + uint16_t ipv6_orport = 0;

if (BUG(!ri_out)) { result = TOR_ROUTERINFO_ERROR_INTERNAL_BUG; @@ -2067,10 +2068,13 @@ router_build_fresh_unsigned_routerinfo,(routerinfo_t **ri_out)) ri->ipv4_orport = router_get_advertised_or_port_by_af(options, AF_INET); ri->ipv4_dirport = router_get_advertised_dir_port(options, 0);

- /* IPv6. */ - if (have_v6) { + /* IPv6. Do not publish an IPv6 if we don't have an ORPort that can be used + * with the address. This is possible for instance if the ORPort is + * IPv4Only. */ + ipv6_orport = router_get_advertised_or_port_by_af(options, AF_INET6); + if (have_v6 && ipv6_orport != 0) { tor_addr_copy(&ri->ipv6_addr, &ipv6_addr); - ri->ipv6_orport = router_get_advertised_or_port_by_af(options, AF_INET6); + ri->ipv6_orport = ipv6_orport; }

ri->supports_tunnelled_dir_requests =