Remove AuthDirPublishIPv6 and let AuthDirHasIPv6Connectivity fill its function.

See #4771 for rationale.

Note that this patch does not take suggested changes in #4470 into
account and keeps treating AuthDirHasIPv6Connectivity as an
AUTOBOOL. Thus, bug fixes for that are included here as well.

This is a fix on master, unreleased as of now.

src/or/config.c

@@ -205,7 +205,6 @@ static config_var_t _option_vars[] = {
   V(AuthDirMaxServersPerAddr,    UINT,     "2"),
   V(AuthDirMaxServersPerAuthAddr,UINT,     "5"),
   V(AuthDirHasIPv6Connectivity,  AUTOBOOL, "auto"),
-  V(AuthDirPublishIPv6,          BOOL,     "0"),
   VAR("AuthoritativeDirectory",  BOOL, AuthoritativeDir,    "0"),
   V(AutomapHostsOnResolve,       BOOL,     "0"),
   V(AutomapHostsSuffixes,        CSV,      ".onion,.exit"),

src/or/dirserv.c

@@ -1017,7 +1017,7 @@ dirserv_set_router_is_running(routerinfo_t *router, time_t now)
        IPv6 OR port since that'd kill all dual stack relays until a
        majority of the dir auths have IPv6 connectivity. */
     answer = (now < node->last_reachable + REACHABLE_TIMEOUT &&
-              (options->AuthDirHasIPv6Connectivity == 0 ||
+              (options->AuthDirHasIPv6Connectivity != 1 ||
                tor_addr_is_null(&router->ipv6_addr) ||
                now < node->last_reachable6 + REACHABLE_TIMEOUT));
   }
@@ -2495,13 +2495,11 @@ set_routerstatus_from_routerinfo(routerstatus_t *rs,
   strlcpy(rs->nickname, ri->nickname, sizeof(rs->nickname));
   rs->or_port = ri->or_port;
   rs->dir_port = ri->dir_port;
-  if (options->AuthDirPublishIPv6 == 1 &&
+  if (options->AuthDirHasIPv6Connectivity == 1 &&
       !tor_addr_is_null(&ri->ipv6_addr) &&
-      (options->AuthDirHasIPv6Connectivity == 0 ||
-       node->last_reachable6 >= now - REACHABLE_TIMEOUT)) {
-    /* We're configured for publishing IPv6 OR ports. There's an IPv6
-       OR port and it's reachable (or we know that we're not on IPv6)
-       so copy it to the routerstatus.  */
+      node->last_reachable6 >= now - REACHABLE_TIMEOUT) {
+    /* We're configured as having IPv6 connectivity. There's an IPv6
+       OR port and it's reachable so copy it to the routerstatus.  */
     tor_addr_copy(&rs->ipv6_addr, &ri->ipv6_addr);
     rs->ipv6_orport = ri->ipv6_orport;
   }

src/or/or.h

@@ -3324,7 +3324,6 @@ typedef struct {
                                      * number of servers per IP address shared
                                      * with an authority. */
   int AuthDirHasIPv6Connectivity; /**< Autoboolean: are we on IPv6?  */
-  int AuthDirPublishIPv6; /**< Boolean: should we list IPv6 OR ports? */
 
   /** If non-zero, always vote the Fast flag for any relay advertising
    * this amount of capacity or more. */