tor

commit fbee4d25cc5672cd9b4fb79a8cb17c7464053ef8
parent f5d773c600e9902f053d03f47b7812bd1f4796b7
Author: David Goulet <dgoulet@torproject.org>
Date:   Tue, 21 Jul 2020 08:12:47 -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>

Diffstat:
M
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
@@ -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 Do not publish an IPv6 if we don't have an ORPort that can be used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 =