relay: Change router_can_extend_over_ipv6() to look at configured port

In routerconf_find_ipv6_or_ap(), we check if the returned ORPort is internal
but not for listening. This means that IPv6 [::] is considered internal.

Thus, we can't use it, we have to look directly at the configured address and
port and if they are valid, we do consider that we have a valid IPv6 ORPort
and that we can thus extend in IPv6.

Related #33246

Signed-off-by: David Goulet <dgoulet@torproject.org>

1 files changed, 10 insertions, 3 deletions

diff --git a/src/feature/relay/router.c b/src/feature/relay/router.c
index 997be643dc..97a77f9578 100644
--- a/src/feature/relay/router.c
+++ b/src/feature/relay/router.c
@@ -1526,9 +1526,16 @@ routerconf_find_ipv6_or_ap(const or_options_t *options,
 bool
 routerconf_has_ipv6_orport(const or_options_t *options)
 {
-  tor_addr_port_t ipv6_ap;
-  routerconf_find_ipv6_or_ap(options, &ipv6_ap);
-  return tor_addr_port_is_valid_ap(&ipv6_ap, 0);
+  /* What we want here is to learn if we have configured an IPv6 ORPort.
+   * Remember, ORPort can listen on [::] and thus consider internal by
+   * router_get_advertised_ipv6_or_ap() since we do _not_ want to advertise
+   * such address. */
+  const tor_addr_t *addr =
+    portconf_get_first_advertised_addr(CONN_TYPE_OR_LISTENER, AF_INET6);
+  const uint16_t port =
+    routerconf_find_or_port(options, AF_INET6);
+
+  return tor_addr_port_is_valid(addr, port, 1);
 }
 
 /** Returns true if this router can extend over IPv6.