add a "getinfo address" controller command.

svn:r8354

doc/control-spec.txt

@@ -344,6 +344,9 @@ $Id$
       via the control interface; the 'all' target returns the mappings
       set through any mechanism.
 
+    "address" -- the best guess at our external IP address. If we
+      have no guess, return a 551 error.
+
     "circuit-status"
       A series of lines as for a circuit status event. Each line is of
       the form:

src/or/control.c

@@ -1307,6 +1307,7 @@ list_getinfo_options(void)
     "addr-mappings/cache Addresses remapped by DNS cache.\n"
     "addr-mappings/configl Addresses remapped from configuration options.\n"
     "addr-mappings/control Addresses remapped by a controller.\n"
+    "address The best guess at our external IP address.\n"
     "circuit-status Status of each current circuit.\n"
     "config-file Current location of the \"torrc\" file.\n"
     "config/names List of configuration options, types, and documentation.\n"
@@ -1325,7 +1326,7 @@ list_getinfo_options(void)
 
 /** Lookup the 'getinfo' entry <b>question</b>, and return
  * the answer in <b>*answer</b> (or NULL if key not recognized).
- * Return 0 if success, or -1 if internal error. */
+ * Return 0 if success, or -1 if recognized but internal error. */
 static int
 handle_getinfo_helper(const char *question, char **answer)
 {
@@ -1520,6 +1521,11 @@ handle_getinfo_helper(const char *question, char **answer)
     *answer = smartlist_join_strings(mappings, "\n", 0, NULL);
     SMARTLIST_FOREACH(mappings, char *, cp, tor_free(cp));
     smartlist_free(mappings);
+  } else if (!strcmp(question, "address")) {
+    uint32_t addr;
+    if (router_pick_published_address(get_options(), &addr) < 0)
+      return -1;
+    *answer = tor_dup_addr(addr);
   } else if (!strcmp(question, "dir-usage")) {
     *answer = directory_dump_request_log();
   } else if (!strcmpstart(question, "dir/server/")) {

src/or/or.h

@@ -2464,6 +2464,7 @@ const char *router_get_my_descriptor(void);
 int router_digest_is_me(const char *digest);
 int router_is_me(routerinfo_t *router);
 int router_fingerprint_is_me(const char *fp);
+int router_pick_published_address(or_options_t *options, uint32_t *addr);
 int router_rebuild_descriptor(int force);
 int router_dump_router_to_string(char *s, size_t maxlen, routerinfo_t *router,
                                  crypto_pk_env_t *ident_key);

src/or/router.c

@@ -729,6 +729,24 @@ static smartlist_t *warned_nonexistent_family = NULL;
 
 static int router_guess_address_from_dir_headers(uint32_t *guess);
 
+/** Return our current best guess at our address, either because
+ * it's configured in torrc, or because we've learned it from
+ * dirserver headers. */
+int
+router_pick_published_address(or_options_t *options, uint32_t *addr)
+{
+  if (resolve_my_address(LOG_INFO, options, addr, NULL) < 0) {
+    log_info(LD_CONFIG, "Could not determine our address locally. "
+             "Checking if directory headers provide any hints.");
+    if (router_guess_address_from_dir_headers(addr) < 0) {
+      log_info(LD_CONFIG, "No hints from directory headers either. "
+               "Will try again later.");
+      return -1;
+    }
+  }
+  return 0;
+}
+
 /** If <b>force</b> is true, or our descriptor is out-of-date, rebuild
  * a fresh routerinfo and signed server descriptor for this OR.
  * Return 0 on success, -1 on temporary error.
@@ -745,18 +763,12 @@ router_rebuild_descriptor(int force)
   if (desc_clean_since && !force)
     return 0;
 
-  if (resolve_my_address(LOG_INFO, options, &addr, NULL) < 0) {
-    log_info(LD_CONFIG, "Could not determine our address locally. "
-             "Checking if directory headers provide any hints.");
-    if (router_guess_address_from_dir_headers(&addr) < 0) {
-      log_info(LD_CONFIG, "No hints from directory headers either. "
-               "Will try again later.");
-      /* Stop trying to rebuild our descriptor every second. We'll
-       * learn that it's time to try again when server_has_changed_ip()
-       * marks it dirty. */
-      desc_clean_since = time(NULL);
-      return -1;
-    }
+  if (router_pick_published_address(options, &addr) < 0) {
+    /* Stop trying to rebuild our descriptor every second. We'll
+     * learn that it's time to try again when server_has_changed_ip()
+     * marks it dirty. */
+    desc_clean_since = time(NULL);
+    return -1;
   }
 
   ri = tor_malloc_zero(sizeof(routerinfo_t));